Science.gov

Sample records for support studies expansion

  1. Stakeholder Support for School Food Policy Expansions

    ERIC Educational Resources Information Center

    Pettigrew, Simone; Pescud, Melanie; Donovan, Robert J.

    2012-01-01

    The aim of this study was to assess the extent to which parents and school-based stakeholders (principals, teachers, canteen managers and Parents & Citizen Committee presidents) are supportive of potential expansions to a new school food policy. Eight additional policy components elicited in preliminary focus groups with parents and 19 additional…

  2. Supporting decision makers in land use planning around chemical sites. Case study: expansion of an oil refinery.

    PubMed

    Papazoglou, I A; Bonanos, G S; Nivolianitou, Z S; Duijm, N J; Rasmussen, B

    2000-01-07

    An approach for supporting decisions on land use around chemical sites - along with a software decision support system (DSS) - based on multi-criteria decision analysis (MCDA; and particularly on the establishment of the set of efficient solutions and letting the final selection depend on local procedures and value tradeoffs) is being illustrated through a case study where five alternative expansions of a refinery are considered along with the existing situation. Alternative land use plans are based on combinations of alternative uses of specific land cells coupled with alternative expansion options. Criteria for evaluating alternative land use plans are the potential loss of life (PLL), the noise levels and the economic benefit resulting for each specific land use plan.

  3. Welwistatin Support Studies: Expansion and Limitation of Aryllead(IV) Coupling Reactions

    PubMed Central

    Xia, Jibo; Brown, Lauren E.

    2008-01-01

    Recent support studies on the total synthesis of the welwitstatin system are described. The target step involves lead-mediated arylation of sterically demanding aryl groups and carbon acid coupling partners in order to establish the highly congested tetracyclic core structure. Type 7 β-ketoesters and β-ketonitriles were successfully arylated with a variety of ortho- and meta-subsituted aryllead compounds generated by a halogen-boron-lead exchange sequence. The enolates of compounds 15, 19 and 25, each bearing all-carbon quaternary centers adjacent to the arylation site, failed to couple. PMID:17685656

  4. Dentoskeletal effects of a temporary skeletal anchorage device-supported rapid maxillary expansion appliance (TSADRME): A pilot study.

    PubMed

    Vassar, Jason William; Karydis, Anastasios; Trojan, Terry; Fisher, Jack

    2016-03-01

    To quantitatively evaluate maxillary skeletal expansion using cone-beam computed tomography (CBCT) images and propose a novel way to quantify the dental tipping effects of temporary skeletal anchorage device-supported rapid maxillary expansion appliance (TSADRME). Images from 25 patients receiving rapid maxillary expansion with incorporated temporary skeletal anchorage devices (TSADs) before activation (T1) and after removal (T2) were analyzed to detect dentoskeletal changes. A significant increase from T1 to T2 was found for all linear measurements except buccal maxillary width at the canines. The greatest buccal expansion was at the first molar, decreasing anteriorly. However, the greatest palatal expansion was at the first premolar. All younger subjects (8-16 years old) exhibited less dental tipping and greater expansion overall compared with the older subjects. There was great variability in dental tipping of first molars (mean = 4.31°), with some subjects demonstrating mild uprighting of these teeth. The TSADRME appliance is an effective, clinically useful device that results in mild molar tipping and may positively affect expansion in the area of TSAD placement.

  5. Urban Expansion Study

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Under an Egyptian government contract, PADCO studies urban growth in the Nile Area. They were assisted by LANDSAT survey maps and measurements provided by TAC. TAC had classified the raw LANDSAT data and processed it into various categories to detail urban expansion. PADCO crews spot checked the results, and correlations were established.

  6. Low thermal expansion seal ring support

    DOEpatents

    Dewis, David W.; Glezer, Boris

    2000-01-01

    Today, the trend is to increase the temperature of operation of gas turbine engines. To cool the components with compressor discharge air, robs air which could otherwise be used for combustion and creates a less efficient gas turbine engine. The present low thermal expansion sealing ring support system reduces the quantity of cooling air required while maintaining life and longevity of the components. Additionally, the low thermal expansion sealing ring reduces the clearance "C","C'" demanded between the interface between the sealing surface and the tip of the plurality of turbine blades. The sealing ring is supported by a plurality of support members in a manner in which the sealing ring and the plurality of support members independently expand and contract relative to each other and to other gas turbine engine components.

  7. Extracellular Vesicles from Bovine Follicular Fluid Support Cumulus Expansion.

    PubMed

    Hung, Wei-Ting; Hong, Xioman; Christenson, Lane K; McGinnis, Lynda K

    2015-11-01

    Expansion of the cumulus complex surrounding the oocyte is critical for ovulation of a fertilizable egg. The ovulation-inducing surge of luteinizing hormone leads to an increased expression of genes such as prostaglandin-endoperoxide synthase 2 (Ptgs2), pentraxin-related protein 3 (Ptx3), and tumor necrosis factor alpha-induced protein 6 (Tnfaip6) that support cumulus expansion. Factors released by mural granulosa and cumulus granulosa cells into the follicular fluid induce paracrine signaling within the follicular compartment. The follicular fluid that separates these distinct granulosa cell types is an enriched fluid containing numerous proteins, nucleic acids, and other macromolecules. Extracellular vesicles (EVs) are also present; however, no physiologically relevant functions of follicular EVs have yet been demonstrated. In our study, the effect of follicular EVs on cumulus-oocyte complex (COC) expansion and relevant gene expression was assayed. Follicular EVs were isolated using ultracentrifugation from follicular fluid of small (3-5 mm) and large (>9 mm) antral bovine follicles, then characterized by nanoparticle tracking analysis, electron microscopy, and Western blot analysis. To test for bioactivity, mouse and bovine COCs were cultured with follicular EVs. Cumulus expansion and Ptgs2, Ptx3, and Tnfaip6 gene expression were measured following COC maturation culture. The results demonstrated that follicular EVs can support both measurable cumulus expansion and increased gene expression.

  8. Extracellular Vesicles from Bovine Follicular Fluid Support Cumulus Expansion1

    PubMed Central

    Hung, Wei-Ting; Hong, Xioman; Christenson, Lane K.; McGinnis, Lynda K.

    2015-01-01

    Expansion of the cumulus complex surrounding the oocyte is critical for ovulation of a fertilizable egg. The ovulation-inducing surge of luteinizing hormone leads to an increased expression of genes such as prostaglandin-endoperoxide synthase 2 (Ptgs2), pentraxin-related protein 3 (Ptx3), and tumor necrosis factor alpha-induced protein 6 (Tnfaip6) that support cumulus expansion. Factors released by mural granulosa and cumulus granulosa cells into the follicular fluid induce paracrine signaling within the follicular compartment. The follicular fluid that separates these distinct granulosa cell types is an enriched fluid containing numerous proteins, nucleic acids, and other macromolecules. Extracellular vesicles (EVs) are also present; however, no physiologically relevant functions of follicular EVs have yet been demonstrated. In our study, the effect of follicular EVs on cumulus-oocyte complex (COC) expansion and relevant gene expression was assayed. Follicular EVs were isolated using ultracentrifugation from follicular fluid of small (3–5 mm) and large (>9 mm) antral bovine follicles, then characterized by nanoparticle tracking analysis, electron microscopy, and Western blot analysis. To test for bioactivity, mouse and bovine COCs were cultured with follicular EVs. Cumulus expansion and Ptgs2, Ptx3, and Tnfaip6 gene expression were measured following COC maturation culture. The results demonstrated that follicular EVs can support both measurable cumulus expansion and increased gene expression. PMID:26423123

  9. 78 FR 21610 - Expansion Funds for the Support of the Senior Medicare Patrol (SMP) Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-11

    ... HUMAN SERVICES Administration for Community Living Expansion Funds for the Support of the Senior... Administration for Community Living is announcing the availability of expansion funds for the support of the..., train, and support the SMP volunteer network. In addition, this funding opportunity will increase...

  10. Fetal hepatic progenitors support long-term expansion of hematopoietic stem cells.

    PubMed

    Chou, Song; Flygare, Johan; Lodish, Harvey F

    2013-05-01

    We have developed a coculture system that establishes DLK(+) fetal hepatic progenitors as the authentic supportive cells for expansion of hematopoietic stem (HSCs) and progenitor cells. In 1-week cultures supplemented with serum and supportive cytokines, both cocultured DLK(+) fetal hepatic progenitors and their conditioned medium supported rapid expansion of hematopoietic progenitors and a small increase in HSC numbers. In 2- and 3-week cultures DLK(+) cells, but not their conditioned medium, continuously and significantly (>20-fold) expanded both hematopoietic stem and progenitor cells. Physical contact between HSCs and DLK(+) cells was crucial to maintaining this long-term expansion. Similar HSC expansion (approximately sevenfold) was achieved in cocultures using a serum-free, low cytokine- containing medium. In contrast, DLK(-) cells are incapable of expanding hematopoietic cells, demonstrating that hepatic progenitors are the principle supportive cells for HSC expansion in the fetal liver.

  11. UTD at TREC 2014: Query Expansion for Clinical Decision Support

    DTIC Science & Technology

    2014-11-01

    Syntactically process the medical case descrip- tion with the shallow parser available from OpenNLP [1] and derive all the noun phrases , generating a...de- scribed in Section 2.1 leverages two sources of infor- mation to determine likely key- phrases : Wikipedia and syntactic noun phrases . This allows... phrase detec- tion, (2) an extended approach incorporating medi- cal knowledge bases for query expansion, (3) a fur- ther extended approach which

  12. Study of stellarator devices by expansion techniques

    SciTech Connect

    Johnson, J.L.; Boozer, A.H.; Koniges, A.E.; Kuo-Petravic, G.; Manickam, J.; Monticello, D.A.; Mynick, H.; Park, W.; Reiman, A.; Rewoldt, G.

    1984-09-01

    Expansion techniques have led to new tools for designing stellarators and interpreting experimental results. The stellarator expansion is coupled with Hamiltonian techniques to investigate the effect of plasma pressure on magnetic surface structure. An expansion for nonplanar-axis systems is described. A reduced-equation initial-value formalism is used to create three-dimensional heliac equilibria. A low-..beta.. expansion with an auxiliary expansion about the magnetic axis makes possible the determination of island widths in heliacs and allows analytic determination of the effect of equilibrium modifications associated with plasma pressure on radial transport.

  13. High flux expansion divertor studies in NSTX

    SciTech Connect

    Soukhanovskii, V A; Maingi, R; Bell, R E; Gates, D A; Kaita, R; Kugel, H W; LeBlanc, B P; Maqueda, R; Menard, J E; Mueller, D; Paul, S F; Raman, R; Roquemore, A L

    2009-06-29

    Projections for high-performance H-mode scenarios in spherical torus (ST)-based devices assume low electron collisionality for increased efficiency of the neutral beam current drive. At lower collisionality (lower density), the mitigation techniques based on induced divertor volumetric power and momentum losses may not be capable of reducing heat and material erosion to acceptable levels in a compact ST divertor. Divertor geometry can also be used to reduce high peak heat and particle fluxes by flaring a scrape-off layer (SOL) flux tube at the divertor plate, and by optimizing the angle at which the flux tube intersects the divertor plate, or reduce heat flow to the divertor by increasing the length of the flux tube. The recently proposed advanced divertor concepts [1, 2] take advantage of these geometry effects. In a high triangularity ST plasma configuration, the magnetic flux expansion at the divertor strike point (SP) is inherently high, leading to a reduction of heat and particle fluxes and a facilitated access to the outer SP detachment, as has been demonstrated recently in NSTX [3]. The natural synergy of the highly-shaped high-performance ST plasmas with beneficial divertor properties motivated a further systematic study of the high flux expansion divertor. The National Spherical Torus Experiment (NSTX) is a mid-sized device with the aspect ratio A = 1.3-1.5 [4]. In NSTX, the graphite tile divertor has an open horizontal plate geometry. The divertor magnetic configuration geometry was systematically changed in an experiment by either (1) changing the distance between the lower divertor X-point and the divertor plate (X-point height h{sub X}), or by (2) keeping the X-point height constant and increasing the outer SP radius. An initial analysis of the former experiment is presented below. Since in the divertor the poloidal field B{sub {theta}} strength is proportional to h{sub X}, the X-point height variation changed the divertor plasma wetted area due to

  14. Medicaid expansion and mental health: A Minnesota case study.

    PubMed

    Diaz Vickery, Katherine; Guzman-Corrales, Laura; Owen, Ross; Soderlund, Dana; Shimotsu, Scott; Clifford, Pam; Linzer, Mark

    2016-03-01

    The health status and psychosocial needs of the Medicaid expansion population have been estimated but not measured. This population includes childless adults predicted to have high rates of mental illness, especially among the homeless. Given limitations in access to mental health services, it is unclear how prepared the U.S. health care system is to care for the needs of the expansion population. Using enrollment and claims data from the Minnesota Department of Human Services, this study presents prevalence rates of mental illness diagnoses and measures of unstable housing in Minnesota's childless-adult early Medicaid expansion population. Rates are compared with prior predictions of serious psychological distress and mental illness constructed from the National Survey on Drug Use and Health (NSDUH) using χ2 and t tests. Diagnoses of mental illness in Minnesota's childless-adult early Medicaid expansion population were more than 15% higher than prevalence measures of mental illness/distress for the current Medicaid population. Diagnosis rates fell within confidence intervals of estimates of mental illness for Minnesota's Medicaid expansion population. Almost 1 in 3 enrollees had a marker of unstable housing; of this group, half had mental illness and/or distress. Findings support predictions of the high burden of mental illness and unstable housing among the Medicaid expansion population. Minnesota offers lessons to other regions working to care for such populations: (a) the use of flexible financing structures to build integrated care systems and (b) passage of legislation to allow data sharing among mental health, social services, and medical care. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  15. Microsatellite data support an early population expansion in Africa.

    PubMed

    Shriver, M D; Jin, L; Ferrell, R E; Deka, R

    1997-06-01

    We have developed a method for the analysis of microsatellite data that is useful in the elucidation of the demographic history of populations. This method, the PK distribution method of pairwise comparisons, is analogous to the mismatch distribution of sequence comparisons developed for the analysis of mitochondrial sequence data by Rodgers and Harpending and is defined as the distribution of the number of repeat unit differences between alleles when each allele in a sample is compared with every other allele in the sample. Using computer simulations of microsatellite loci, we show that the shape of the distribution of PK changes in a distinctive manner as a function either of time since population expansion or effective population size. Increases in both of these affect the PK distribution in a similar fashion leading to a change from a steep distribution with a Po peak to one with a nonzero peak. Analysis of three data sets from surveys of microsatellite loci in ethnographically defined populations reveals that most (9/12) of the African populations analyzed, but none of the 30 non-African populations showed PK distributions with nonzero peaks. These PK distributions indicate either an earlier expansion or a larger effective population size for African populations. This observation is consistent with the hypothesized African origin of modern human.

  16. Rapid maxillary expansion assisted by palatal mini-implants in adolescents - preliminary study.

    PubMed

    Chane-Fane, Caroline; Darqué, François

    2015-03-01

    Our preliminary clinical study compares the transverse skeletal and dento-alveolar modifications occurring after rapid maxillary expansion with purely dental anchorage or with dental anchorage assisted by palatal mini-implants, in endognathic adolescents aged 12 to 17. Nine patients were treated by means of tooth- and implant-supported expansion, and 7 others by means of a purely tooth-borne expander. The changes, 4 months after expansion, were measured on impressions and front-view X-rays in the 2 groups, and on three-dimensional X-rays for 6 patients treated by tooth- and implant-supported expansion. In our sample, tooth- and implant-supported expansion preserved the alveolar bone of 14/24 and gave rise to less buccal tipping of 16/26 than purely tooth-borne expansion.

  17. Elastic hydrogel substrate supports robust expansion of murine myoblasts and enhances their engraftment

    SciTech Connect

    Ding, Ke; Yang, Zhong; Xu, Jian-zhong; Liu, Wen-ying; Zeng, Qiang; Hou, Fang; Lin, Sen

    2015-09-10

    The application of satellite cell-derived myoblasts in regenerative medicine has been restricted by the rapid loss of stemness during in vitro cell expansion using traditional culture systems. However, studies published in the past decade have highlighted the influence of substrate elasticity on stem cell fate and revealed that culture on a soft hydrogel substrate can promote self-renewal and prolong the regenerative potential of muscle stem cells. Whether hydrogel substrates have similar effects after long-term robust expansion remains to be determined. Herein we prepared an elastic chitosan/beta-glycerophosphate/collagen hydrogel mimicking the soft microenvironment of muscle tissues for use as the substrate for satellite cell culture and investigated its influence on long-term cell expansion. After 20 passages in culture, satellite cell-derived myoblasts cultured on our hydrogel substrate exhibited significant improvements in proliferation capability, cell viability, colony forming frequency, and potential for myogenic differentiation compared to those cultured on a routine rigid culture surface. Immunochemical staining and western blot analysis both confirmed that myoblasts cultured on the hydrogel substrate expressed higher levels of several differentiation-related markers, including Pax7, Pax3, and SSEA-1, and a lower level of MyoD compared to myoblasts cultured on rigid culture plates (all p<0.05). After transplantation into the tibialis anterior of nude mice, myoblasts that had been cultured on the hydrogel substrate demonstrated a significantly greater engraftment efficacy than those cultured on the traditional surface. Collectively, these results indicate that the elastic hydrogel substrate supported robust expansion of murine myoblasts and enhanced their engraftment in vivo. - Highlights: • An elastic hydrogel was designed to mimic the pliable muscle tissue microenvironment. • Myoblasts retained their stemness in long-term culture on the elastic

  18. MtDNA analysis of global populations support that major population expansions began before Neolithic Time

    NASA Astrophysics Data System (ADS)

    Zheng, Hong-Xiang; Yan, Shi; Qin, Zhen-Dong; Jin, Li

    2012-10-01

    Agriculture resulted in extensive population growths and human activities. However, whether major human expansions started after Neolithic Time still remained controversial. With the benefit of 1000 Genome Project, we were able to analyze a total of 910 samples from 11 populations in Africa, Europe and Americas. From these random samples, we identified the expansion lineages and reconstructed the historical demographic variations. In all the three continents, we found that most major lineage expansions (11 out of 15 star lineages in Africa, all autochthonous lineages in Europe and America) coalesced before the first appearance of agriculture. Furthermore, major population expansions were estimated after Last Glacial Maximum but before Neolithic Time, also corresponding to the result of major lineage expansions. Considering results in current and previous study, global mtDNA evidence showed that rising temperature after Last Glacial Maximum offered amiable environments and might be the most important factor for prehistorical human expansions.

  19. Multiple mechanisms support oligoclonal T cell expansion in rheumatoid synovitis.

    PubMed Central

    Rittner, H. L.; Zettl, A.; Jendro, M. C.; Bartz-Bazzanella, P.; Goronzy, J. J.; Weyand, C. M.

    1997-01-01

    to the T cell infiltrate in rheumatoid synovitis. Differences in the distribution pattern and in molecular features suggest that distinct mechanisms are supporting the clonal outgrowth of these two groups of clonotypes. Clonally expanded T cells restricted to the joint but present in several independent joints appear to respond to locally residing antigens. Clonogenic cells with an unrestricted distribution pattern and widespread activation in the blood and tissue may react to a different class of antigens which appear to be shared by multiple patients. T cell recognition in RA may be involved at several different levels and may be related to more than one pathomechanism. Images FIG. 1 FIG. 2 FIG. 4 PMID:9260157

  20. Extensiometric analysis of strain in craniofacial bones during implant-supported palatal expansion.

    PubMed

    Nelson Elias, Carlos; Jogaib Fernandes, Daniel; Souza Zanivan, Denis; Resende Fonseca, Yuri

    2017-05-25

    Palatal expansion has several orthodontic and orthopedic applications, such as increasing maxillary transverse dimensions and correcting maxillary atresia, oral breathing, and skeletal cross-bites. Little is known about the strain to which craniofacial bones are submitted when a palatal expander is loaded. The objectives of the present work were to propose a new palatal bone-borne titanium device (expansion screw), to determine patterns of strain distribution in craniofacial bones during palatal expansion and to show the clinical results of a new palatal expander supported by implants. For in vitro testing, the palatal expander supported by two commercially pure titanium (cp Ti) implants was inserted parallel to the median palatine suture of four dry adult human skulls. Uniaxial and triaxial strain gauges were attached to craniofacial bones and connected to a signal acquisition system. An expansion screw was turned and strain data were collected during palatal expansion. The results showed that the bone strain distribution in craniofacial bones loaded by the palatal bone-borne titanium device was complex: the strain was tensile in the palatine cortical bone and compressive in pterygopalatine processes, nasal bones, and orbital floor. The maximum compressive strain occurs in the upper portion of the pterygopalatine processes and the strain changes from compressive to tensile in the zygomatic process. The experimental results suggest that the bone strain due to the palatal expander is distributed over all craniofacial bones and that the upper portions of pterygopalatine processes are the main sites of resistance to palatal expansion. The new palatal expander supported by two cp Ti implants proposed was employed on adult patient as an illustrative report, where adequate palatal expansion was achieved. The new protocol proposed was less invasive, risky, painful and costless for the correction of moderate maxillary transverse deficiency. Copyright © 2017. Published by

  1. Phonemic diversity supports a serial founder effect model of language expansion from Africa.

    PubMed

    Atkinson, Quentin D

    2011-04-15

    Human genetic and phenotypic diversity declines with distance from Africa, as predicted by a serial founder effect in which successive population bottlenecks during range expansion progressively reduce diversity, underpinning support for an African origin of modern humans. Recent work suggests that a similar founder effect may operate on human culture and language. Here I show that the number of phonemes used in a global sample of 504 languages is also clinal and fits a serial founder-effect model of expansion from an inferred origin in Africa. This result, which is not explained by more recent demographic history, local language diversity, or statistical non-independence within language families, points to parallel mechanisms shaping genetic and linguistic diversity and supports an African origin of modern human languages.

  2. Support effects studied on model supported catalysts

    SciTech Connect

    Gorte, R.J.

    1993-02-01

    Composition and structure of oxide support materials can change the catalytic behavior of metal and oxide catalysts. Model catalysts are being studied in which the active phase is deposited on flat oxide substrates, with emphasis on metals catalysis for automotive emissions control and acidity in supported oxides. Research is reported in the following areas: particle-size effects, support effects on ZnO and zirconia, support effects on ceria, supported oxides, and low energy ion scattering (no results in the latter).

  3. New roles to support practice learning - can they facilitate expansion of placement capacity?

    PubMed

    Magnusson, C; O'Driscoll, M; Smith, P

    2007-08-01

    The National Health Service (NHS) Plan [Department of Health, 2000. The NHS Plan: A Plan for Investment, a Plan for Reform, The Stationery Office, London] set out an ambitious programme of growth for the number of students undertaking health professional education programmes. To meet this demand there is a growing and widely acknowledged need to increase the number of clinical placements needed by these students. This paper outlines the findings from a regional project that aimed to map the current pattern and availability of clinical placements for healthcare students by the collection of quantitative placement data (such as location, specialty, and number of mentors) as well as in-depth interviews with Clinical Placement Managers (CPMs). This article will focus on the findings from interviews with CPMs and their views and experiences of what role they can play in increasing placement capacity. The study revealed that the introduction of this role had facilitated the development and expansion of placement capacity, as the CPMs filled a gap in the form of up-to-date local knowledge about the clinical areas. The CPMs provided a much needed 'bridge' between the Higher Education Institution (HEI), the student and the clinical area. Recommendations are made in relation to future introduction of similar roles that aim to support student learning in practice. Furthermore, useful insights for ongoing policy implementation and development are highlighted.

  4. Low perceived social support is associated with CD8+CD57+ lymphocyte expansion and increased TNF-α levels.

    PubMed

    Copertaro, Alfredo; Bracci, Massimo; Manzella, Nicola; Barbaresi, Mariella; Copertaro, Benedetta; Santarelli, Lory

    2014-01-01

    Social support has been supposed to have a positive impact on the function of the immune system. However, the relationship between perceived social support and immune function has not yet been fully investigated. In this cross-sectional study, we investigated the link between perceived social support and lymphocyte subpopulations and cytokines. 232 healthy subjects provided a blood sample and completed the Multidimensional Scale of Perceived Social Support (MSPSS) questionnaire. Lymphocyte immunophenotypes and cytokines were determined. Significantly increased CD8+CD57+ lymphocytes and TNF-α levels were found in group with low perceived social support. Multivariate linear regression corrected for possible confounders confirmed a significant role of perceived social support in predicting the number of CD8+CD57+ lymphocyte and TNF-α levels. This study supports the association between perceived social support and immune function. In particular, poor social support may be related to a state of chronic inflammation sustained by CD8+CD57+ lymphocyte expansion and increased TNF-α levels.

  5. Studies of Expansive Learning: Foundations, Findings and Future Challenges

    ERIC Educational Resources Information Center

    Engestrom, Yrjo; Sannino, Annalisa

    2010-01-01

    The paper examines studies based on the theory of expansive learning, formulated in 1987. In recent years the theory has been used in a wide variety of studies and interventions. The theory builds on foundational ideas put forward by Vygotsky, Leont'ev, Il'enkov, and Davydov, key figures in the Russian school of cultural-historical activity…

  6. Ab-initio study of thermal expansion in pure graphene

    SciTech Connect

    Mann, Sarita; Kumar, Ranjan; Jindal, V. K.; Rani, Pooja

    2016-05-23

    Graphene is a zero band gap semiconductor with exceptionally high thermal conductivity. The electronic properties having been studied, therole of phonon in contributing to thermal expansion, thermal conductivity and other thermodynamic properties, is required to be investigated. This paper focuses more on thermal expansion. Some others results like phonon dispersion, Grüneisenparameters and bulk modulus,which are essential to estimation of thermal expansion, are also presented. The dynamical matrix was calculated using VASP code using both DFT and DFPT and the phonon frequencies were calculated using phonopy code under harmonic approximation. The linear thermal expansion coefficient of graphene is found to be strongly dependent on temperature but remains negative upto 470 K and positive thereafter, with a room temperature value of −1.44×10{sup −6}. The negative expansion coefficient is very interesting and is found to be in conformity with experimental as well as with recent theoretical estimates. There is only qualitative agreement of our results with experimental data and motivates further investigation, primarily on the high negative values of Grüneisen parameters.

  7. Advanced life support study

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Summary reports on each of the eight tasks undertaken by this contract are given. Discussed here is an evaluation of a Closed Ecological Life Support System (CELSS), including modeling and analysis of Physical/Chemical Closed Loop Life Support (P/C CLLS); the Environmental Control and Life Support Systems (ECLSS) evolution - Intermodule Ventilation study; advanced technologies interface requirements relative to ECLSS; an ECLSS resupply analysis; the ECLSS module addition relocation systems engineering analysis; an ECLSS cost/benefit analysis to identify rack-level interface requirements of the alternate technologies evaluated in the ventilation study, with a comparison of these with the rack level interface requirements for the baseline technologies; advanced instrumentation - technology database enhancement; and a clean room survey and assessment of various ECLSS evaluation options for different growth scenarios.

  8. Collisionless expansion of pulsed radio frequency plasmas. II. Parameter study

    NASA Astrophysics Data System (ADS)

    Schröder, T.; Grulke, O.; Klinger, T.; Boswell, R. W.; Charles, C.

    2016-01-01

    The plasma parameter dependencies of the dynamics during the expansion of plasma are studied with the use of a versatile particle-in-cell simulation tailored to a plasma expansion experiment [Schröder et al., J. Phys. D: Appl. Phys. 47, 055207 (2014); Schröder et al., Phys. Plasmas 23, 013511 (2016)]. The plasma expansion into a low-density ambient plasma features a propagating ion front that is preceding a density plateau. It has been shown that the front formation is entangled with a wave-breaking mechanism, i.e., an ion collapse [Sack and Schamel, Plasma Phys. Controlled Fusion 27, 717 (1985); Sack and Schamel, Phys. Lett. A 110, 206 (1985)], and the launch of an ion burst [Schröder et al., Phys. Plasmas 23, 013511 (2016)]. The systematic parameter study presented in this paper focuses on the influence on this mechanism its effect on the maximum velocity of the ion front and burst. It is shown that, apart from the well known dependency of the front propagation on the ion sound velocity, it also depends sensitively on the density ratio between main and ambient plasma density. The maximum ion velocity depends further on the initial potential gradient, being mostly influenced by the plasma density ratio in the source and expansion regions. The results of the study are compared with independent numerical studies.

  9. Precision expansion cloud chamber for homogeneous nucleation studies

    NASA Astrophysics Data System (ADS)

    Schmitt, John L.

    1981-11-01

    The author describes an expansion cloud chamber for the study of the nucleation of a single component vapor (homogeneous nucleation). The design draws on the many years of experience in this Center in construction of chambers for homogeneous nucleation of water. Design features of the chamber are: exact control of temperature (±0.03 ° C), pressure (±0.5 mm Hg), and automatic control of cycling. Construction features are: all construction materials are stainless steel, glass, or fluorocarbon plastics; the piston seal is a very flexible welded stainless steel bellows; the chamber can be made very clean by heating under vacuum and it is compatible with many substances, e.g., ethanol, nonane, and toluene. Performance features are: excellent repeatability of the expansion cycle over a temperature range of 45° to —15 °C and in day to day operation. Safety features are: automatic detection and warning and inerting against fire and explosion from combustible vapor in the chamber enclosure. The determination of the gas temperature at the maximum expansion is discussed as well as the importance of the ''fast'' pulse technique for the measurement of high nucleation rates.

  10. Applications of GIS, Advanced Sensors and Habitat Modeling in Support of Desert Tortoise Line Distance, Sampling and Translocation Studies Related to the Proposed Expansion of the Ft. Irwin NTC

    DTIC Science & Technology

    2008-09-25

    in Madagascar, Biological Conservation. 124, Issue 4: 451 - 461. Li, N. (2007) Smart Knowledge Capture for Developing Adaptive Management Systems...deserts, TIR, HIVE and LCTA. Search tool (advanced searching and filtering capabilities) Framework to support hierarchical map navigation

  11. Support effects studied on model supported catalysts

    SciTech Connect

    Gorte, R.G.

    1991-11-01

    We are studying model catalysts in which the active phase is deposited onto flat oxide substrates in order to understand how a catalyst is affected by its support. We have examined the following growth and stability of titania overlayers which had been vapor deposited onto a Rh foil; the growth of Pt films on ZnO(0001)Zn and O(0001)O and compared the results to those obtained for Pt on {alpha}-Al{sub 2}O{sub 3}(0001). Samples were prepared by vapor deposition of Pt onto flat substrates in ultra high vacuum, and metal coverages were measured using a quartz-crystal, film thickness monitor; the structure and CO adsorption properties of Pt films vapor deposited onto a ZrO{sub 2}(100) crystal; the deposition of Rh on a ZrO{sub 2}(100) crystal; The absorption of NO on Pt particles supported on CeO{sub 2}, {alpha}-Al{sub 2}O{sub 3}(0001), and the Zn- and O-polar surfaces of ZnO(0001). We have investigated supported oxides in order to understand the acidic properties that have been reported for monolayer oxides. Our first studies were of amorphous, silicalumina catalysts. Finally, we have also begun to prepare model supported oxides in order to be able to used spectroscopic methods to characterize the sites formed on these materials. Our first studies were of niobia deposition on oxidized Al films and on an {alpha}-Al{sub 2}O{sub 3}(0001) crystal.

  12. 77 FR 65195 - Announcement of the Award of Four Single-Source Program Expansion Supplement Grants To Support...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-25

    ... Program Expansion Supplement Grants To Support Activities Associated With the Tribal Early Learning... participants in the Tribal Early Learning Initiative. SUMMARY: The Administration for Children and Families... their participation in the Tribal Early Learning Initiative. Each of the following grantees is...

  13. Radical ring expansion reactions of methylenecyclopropane derivatives: a theoretical study.

    PubMed

    Ardura, Diego; Sordo, Tomas L

    2006-06-23

    The evolution of the primary radicals from 1-(3-bromopropyl)-2-ethyl-3-methylenecyclopropane, 1-(3-bromopropyl)-1-trimethylsilyl-2-methylenecyclopropane, 1-(3-bromobutyl)-2-ethyl-3-methylenecyclopropane, and 1-(3-bromobutyl)-1-trimethylsilyl-2-methylenecyclopropane was theoretically studied at the ROMP2/6-311++G(d,p)//UB3LYP/6-31G(d,p) theory level taking into account the effect of solvent through a PCM-UAHF model. For the propyl-substituted radicals, the attack of the radical center on the double bond takes place most favorably in an exo fashion. The subsequent ring expansions yield the product corresponding to the rupture of the endo C-C bond as the most favorable one in accordance with the experimental results. In the case of 1-(3-bromobutyl)-2-ethyl-3-methylenecyclopropane, the Gibbs energy barriers for the endo and exo attacks are the same, and the subsequent reversible evolution yields the product corresponding to the rupture of the exo C-C bond as the most favorable one through thermodynamic control in agreement with experiment. Finally, for 1-(3-bromobutyl)-1-trimethylsilyl-2-methylenecyclopropane, our calculations predict that the endo attack is 0.8 kcal/mol more favorable than the exo one. In the subsequent reversible ring expansion, the product corresponding to the rupture of the endo C-C bond is kinetically the most favored one in reasonable agreement with the experimental observations.

  14. Experimental studies of gas-particle mixtures under sudden expansion

    NASA Astrophysics Data System (ADS)

    Zunino, Heather; Adrian, Ronald; Clarke, Amanda; Arizona State University Collaboration; University of Florida Collaboration

    2015-11-01

    High-speed video cameras and pressure sensors were used to capture the movement of a particle bed due to a passing expansion fan created by a diaphragm burst in a shock tube. The particle bed is placed on the high-pressure side (p4) of the shock tube. Once the diaphragm bursts, it expands upward into the low-pressure region (p1). Several interesting structures are captured and examined, including instabilities located at the top surface of the particle bed and particle vacant regions within the bed. These features are discussed along with their relevance to the spikes of material seen radially ejected outward during a cylindrical explosion. The characteristics of this flow are compared for several different pressure regimes. Two-dimensional and three-dimensional Fourier analyses are used to further explore and measure the frequency of the features imaged. 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.

  15. A Study of Two-Term Unit Fraction Expansions via Geometric Approach

    ERIC Educational Resources Information Center

    Man, Yiu-Kwong

    2009-01-01

    In this article, we report a study of two-term unit fraction expansions using a geometric approach. It provides us insight on how to find all two-term unit fraction expansions and identify the property of the expansions with smallest maximal denominators, for a given unit fraction. These findings will be useful to lecturers or teachers involved in…

  16. A Study of Two-Term Unit Fraction Expansions via Geometric Approach

    ERIC Educational Resources Information Center

    Man, Yiu-Kwong

    2009-01-01

    In this article, we report a study of two-term unit fraction expansions using a geometric approach. It provides us insight on how to find all two-term unit fraction expansions and identify the property of the expansions with smallest maximal denominators, for a given unit fraction. These findings will be useful to lecturers or teachers involved in…

  17. Endothelin-1 supports clonal derivation and expansion of cardiovascular progenitors derived from human embryonic stem cells.

    PubMed

    Soh, Boon-Seng; Ng, Shi-Yan; Wu, Hao; Buac, Kristina; Park, Joo-Hye C; Lian, Xiaojun; Xu, Jiejia; Foo, Kylie S; Felldin, Ulrika; He, Xiaobing; Nichane, Massimo; Yang, Henry; Bu, Lei; Li, Ronald A; Lim, Bing; Chien, Kenneth R

    2016-03-08

    Coronary arteriogenesis is a central step in cardiogenesis, requiring coordinated generation and integration of endothelial cell and vascular smooth muscle cells. At present, it is unclear whether the cell fate programme of cardiac progenitors to generate complex muscular or vascular structures is entirely cell autonomous. Here we demonstrate the intrinsic ability of vascular progenitors to develop and self-organize into cardiac tissues by clonally isolating and expanding second heart field cardiovascular progenitors using WNT3A and endothelin-1 (EDN1) human recombinant proteins. Progenitor clones undergo long-term expansion and differentiate primarily into endothelial and smooth muscle cell lineages in vitro, and contribute extensively to coronary-like vessels in vivo, forming a functional human-mouse chimeric circulatory system. Our study identifies EDN1 as a key factor towards the generation and clonal derivation of ISL1(+) vascular intermediates, and demonstrates the intrinsic cell-autonomous nature of these progenitors to differentiate and self-organize into functional vasculatures in vivo.

  18. Zambia : long-term generation expansion study - executive summary.

    SciTech Connect

    Conzelmann, G.; Koritarov, V.; Buehring, W.; Veselka, T.; Decision and Information Sciences

    2008-02-28

    The objective of this study is to analyze possible long-term development options of the Zambian electric power system in the period up to 2015. The analysis involved the hydro operations studies of the Zambezi river basin and the systems planning studies for the least-cost generation expansion planning. Two well-known and widely accepted computer models were used in the analysis: PC-VALORAGUA model for the hydro operations and optimization studies and the WASP-III Plus model for the optimization of long-term system development. The WASP-III Plus model is a part of the Argonne National Laboratory's Energy and Power Evaluation Model (ENPEP). The analysis was conducted in close collaboration with the Zambia Electricity Supply Corporation (ZESCO). On the initiative from The World Bank, the sponsor of the study, ZESCO formed a team of experts that participated in the analysis and were trained in the use of computer models. Both models were transferred to ZESCO free of charge and installed on several computers in the ZESCO corporate offices in Lusaka. In September-October 1995, two members of the ZESCO National Team participated in a 4-week training course at Argonne National Laboratory near Chicago, U.S.A., focusing on the long-term system expansion planning using the WASP and VALORAGUA models. The hydropower operations studies were performed for the whole Zambezi river basin, including the full installation of the Kariba power station, and the Cahora Bassa hydro power station in Mozambique. The analysis also included possible future projects such as Itezhi-Tezhi, Kafue Gorge Lower, and Batoka Gorge power stations. As hydropower operations studies served to determine the operational characteristics of the existing and future hydro power plants, it was necessary to simulate the whole Zambezi river basin in order to take into account all interactions and mutual influences between the hydro power plants. In addition, it allowed for the optimization of reservoir management

  19. The hollow fiber bioreactor as a stroma-supported, serum-free ex vivo expansion platform for human umbilical cord blood cells.

    PubMed

    Xue, Cao; Kwek, Kenneth Y C; Chan, Jerry K Y; Chen, Qingfeng; Lim, Mayasari

    2014-07-01

    The bone marrow microenvironment plays an integral role in the regulation of hematopoiesis. Residing stromal cells and the extracellular matrix in the bone marrow microenvironment provide biological signals that control hematopoietic stem cell (HSC) function. In this study, we developed a bio-mimetic co-culture platform using the hollow fiber bioreactor (HFBR) for ex vivo expansion of HSCs. We evaluated the efficacy of such a platform in comparison to standard cultures performed on tissue culture polystyrene (TCP), using a human stromal cell line (HS-5) as stromal support, co-cultured with lineage-depleted human cord blood cells in serum-free medium supplemented with a cytokine cocktail. Our results showed that the performance of the HFBR in supporting total cell and CD34(+) progenitor cell expansion was comparable to that of cultures on TCP. Cells harvested from the HFBR had a higher clonogenic ability. The performance of ex vivo-expanded cells from the HFBR in hematopoietic reconstitution in humanized mice was comparable to that of the TCP control. Scanning electron microscopy revealed that stroma cell growth inside the HFBR created a three-dimensional cell matrix architecture. These findings demonstrate the feasibility of utilizing the HFBR for creating a complex cell matrix architecture, which may provide good in vitro mimicry of the bone marrow, supporting large-scale expansion of HSCs.

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

    PubMed Central

    Hamilton, Marcus J.; Buchanan, Briggs

    2010-01-01

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

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

    PubMed

    Hamilton, Marcus J; Buchanan, Briggs

    2010-08-30

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

  2. The Expansion of Education: A Brazilian Case Study.

    ERIC Educational Resources Information Center

    Plank, David N.

    1987-01-01

    Analysis of educational expansion in Brazil between 1940 and 1980 indicates that, in most circumstances, enrollment rates were positively related to urbanization, diversification of the occupational structure, and aggregate economic growth. States experiencing heavy in-migration showed a negative effect of migration on enrollment rates during…

  3. The Expansion of Education: A Brazilian Case Study.

    ERIC Educational Resources Information Center

    Plank, David N.

    1987-01-01

    Analysis of educational expansion in Brazil between 1940 and 1980 indicates that, in most circumstances, enrollment rates were positively related to urbanization, diversification of the occupational structure, and aggregate economic growth. States experiencing heavy in-migration showed a negative effect of migration on enrollment rates during…

  4. Dodecaphony: enacting support brokerage in the twelve cash & counseling expansion states.

    PubMed

    Randall, Jennifer; Bekteshi, Venera

    2012-01-01

    Support brokers are entities that provide information and assistance to self-directed clients in Medicaid waiver programs. Although all Cash & Counseling programs have support brokerage, each state has a great deal of liberty in determining how those functions are carried out, who provides those activities, which functions are emphasized and how responsibility for support broker tasks coordinates with other support activities. In this article, we map out the various ways in which states have operationalized the support brokerage concept. Differences in title, qualifications, training, hiring preferences, and caseload are described and further directions for research are suggested.

  5. Thermal expansion coefficient of a water-supported perfluoro-n-eicosane monolayer

    SciTech Connect

    Huang, Z.; Acero, A.A.; Lei, N.; Rice, S.A.; Schlossman, M.L. |; Zhang, Z.

    1995-07-01

    We report the results of grazing incidence X-ray diffraction studies, as a function of temperature, of monolayers of perfluoro-n-eicosane. The experiments were undertaken to test the suggestion that there is a phase transition in this monolayer between 20 and 25{degree}C, in analogy with the transition which occurs in Teflon at about the same temperature. The issue is of importance with respect to determining whether description of the properties of a monolayer requires consideration of only the obvious quasi two dimensional character of the monolayer or requires inclusion of its three dimensional character. Our results do not support the existence of the suggested transition. 7 refs., 4 figs.

  6. [Experimental study on enhancement of tissue expansion with papaverine cream].

    PubMed

    Luan, Jie; Tang, Yong; Yang, Peiying; Zhang, Xuhui; Hou, Dianju; Ma, Guie; Wang, Qian

    2002-01-01

    To evaluate the effect of external use of papaverine cream on enhancement of tissue expansion. 8 mini pigs were randomly divided into 4 groups. During inflation, papaverine was given externally in group A, through a delivery system in group B, though intramuscular injection in group C. Papaverine was not given in group D. The time of inflation, the expansion rate, the surviving length of expanded flaps and the papaverine concentration in the fibrous capsule in each group were examined. Histologic and electroscope examinations of the expanded tissue were made. The average inflation time was 28.9 +/- 4.5 days in group A, 34.0 +/- 2.6 days in group B, 37.6 +/- 4.8 days in group C and 38.5 +/- 3.5 days in group D. There was significant difference between each group(P < 0.05). The average surviving length of expanded flaps in group A was 13.67 +/- 1.28 cm, 11.07 +/- 0.88 cm in group B, 10.79 +/- 0.49 cm in group C, and 9.49 +/- 0.77 cm in group D. There was significant difference between each group (P < 0.01). Histologic examinations of the expanded tissue suggested that there were no significant differences in thickness of epidermis, derma and fibrous capsule among the four groups. Electroscope examinations of the myofibroblast in fibrous capsule showed that there were smaller nuclei, fewer microfilaments and fewer mitochondrias and rougher endoplastic reticulume in group A than those in other groups. The concentration of papaverine in fibrous capsule of group A was 3.5 +/- 1.2 micrograms/g. Papaverine was detected neither in the skin of other groups nor in the blood of all groups. 1. Papaverine cream can permeate through skin and maintain high concentration and continuous effect in local tissue. 2. External use of papaverine cream can inhabit the function of myofibroblast in fibrous capsule, increase inflation rate, accelerate expansion process, and improve microcirculation of the expanded skin with a result of prolongation of surviving length of expanded flaps. 3

  7. The Effect of Ridge Expansion on Implant Stability in Narrow Partially Edentulous Ridges - A Preliminary Clinical Study

    PubMed Central

    Shaik, Latheef Saheb; Meka, Sridhar; Chakravarthi, Srinivas Pandi; Kolli, Naga Neelima Devi; Lingamaneni, Krishna Prasad; Avvaru, Susmita; Tiwari, Rahul

    2016-01-01

    Introduction Currently, dental treatments with better aesthetic results and less treatment time is more acceptable by the patients. Inadequate amount of bone for implant placement at functionally and aesthetically most appropriate position is a common problem. Aim To assess the effect of ridge expansion on implant stability in narrow partially edentulous ridges and to evaluate clinically and radiographically the success of dental implants, placed immediately following ridge expansion procedure. Material and Methods Ten participants (nine males, one female, average age - 28 years) with partial edentulism associated with narrow atrophic alveolar ridges with adequate height and willing to participate in the study were included. The ridge expansion was performed using osteotomes and simultaneous implant placement was done. A total of 10 implants were placed. Stability, achieved ridge width and radiographic crestal bone loss were assessed three months post-operatively. Results Three months follow-up revealed stable implants both clinically and radiographically. All 10 implants were surrounded by adequate amount of bone required for successful functional rehabilitation. Conclusion The study reveals that the technique of ridge expansion using osteotomes is successful in horizontal expansion, in cases of atrophic alveolar ridges thus, eliminating the need for more complex treatment as well as reduces the rehabilitation time along with improving the quality of bone support. PMID:27790575

  8. Hydrogel Environment Supports Cell Culture Expansion of a Grade IV Astrocytoma.

    PubMed

    Jogalekar, Manasi P; Cooper, Leigh G; Serrano, Elba E

    2017-06-07

    Malignant astrocytomas are aggressive cancers of glial origin that can develop into invasive brain tumors. The disease has poor prognosis and high recurrence rate. Astrocytoma cell lines of human origin are an important tool in the experimental pathway from bench to bedside because they afford a convenient intermediate system for in vitro analysis of brain cancer pathogenesis and treatment options. We undertook the current study to determine whether hydrogel culture methods could be adapted to support the growth of astrocytoma cell lines, thereby facilitating a system that may be biologically more similar to in vivo tumor tissue. Our experimental protocols enabled maintenance of Grade IV astrocytoma cell lines in conventional monolayer culture and in the extracellular matrix hydrogel, Geltrex(™). Light and fluorescence microscopy showed that hydrogel environments promoted cellular reorganization from dispersed cells into multilayered aggregates. Transmission electron microscopy revealed the prevalence of autophagy and nuclear membrane distortions in both culture systems. Analysis of microarray Gene Expression Omnibus (GEO) DataSets highlighted expression of genes implicated in pathways for cancer progression and autophagy. A pilot quantitative polymerase chain reaction (qPCR) analysis of the autophagic biomarkers, Beclin 1 (BECN1) and microtubule-associated proteins 1A/1B light chain 3B (MAP1LC3B), with two reference genes (beta actin, ACTB; glyceraldehyde 3-phosphate dehydrogenase, GAPDH), uncovered a relative increase of BECN1 and LC3B in hydrogel cultures of astrocytoma as compared to the monolayer. Taken together, results establish that ultrastructural and molecular characteristics of autophagy are features of this astrocytoma cell line, and that hydrogel culture systems can afford novel opportunities for in vitro studies of glioma.

  9. Laser induced fluorescence study of free jet expansions

    NASA Astrophysics Data System (ADS)

    Willems, H.; Hulsman, H.; Aerts, F.

    The first part of a sodium seeded free jet expansion (from the orifice to about 20 nozzle diameters downsteam) is illuminated with light from a single mode CW dye laser, and the spatial distribution of the resulting fluorescence is measured. Results for different carrier gases (Ar, Ne, He, N2) and different stagnation pressures (1-20 torr-mm) have been obtained. At the highest stagnation pressures the fluorescence intensity distributions are in good agreement with the prediction from MOC calculations. A qualitative analysis of the deviations at lower stagnation pressures is given.

  10. Does Educational Expansion Encourage Female Workforce Participation? A Study of the 1968 Reform in Taiwan

    ERIC Educational Resources Information Center

    Tsai, Wehn-Jyuan; Liu, Jin-Tan; Chou, Shin-Yi; Thornton, Robert

    2009-01-01

    Between 1968 and 1973 the Taiwanese government undertook the most extensive expansion on record of the public junior high school system in Taiwan. This study analyzes the effects of the 1968 education reform and subsequent high school expansion on gender disparities in employment generally, as well in different sectors and classes of employment.…

  11. Does Educational Expansion Encourage Female Workforce Participation? A Study of the 1968 Reform in Taiwan

    ERIC Educational Resources Information Center

    Tsai, Wehn-Jyuan; Liu, Jin-Tan; Chou, Shin-Yi; Thornton, Robert

    2009-01-01

    Between 1968 and 1973 the Taiwanese government undertook the most extensive expansion on record of the public junior high school system in Taiwan. This study analyzes the effects of the 1968 education reform and subsequent high school expansion on gender disparities in employment generally, as well in different sectors and classes of employment.…

  12. Negative Thermal Expansion of Ultrathin Metal Nanowires: A Computational Study.

    PubMed

    Ho, Duc Tam; Kwon, Soon-Yong; Park, Harold S; Kim, Sung Youb

    2017-08-09

    Most materials expand upon heating because the coefficient of thermal expansion (CTE), the fundamental property of materials characterizing the mechanical response of the materials to heating, is positive. There have been some reports of materials that exhibit negative thermal expansion (NTE), but most of these have been in complex alloys, where NTE originates from the transverse vibrations of the materials. Here, we show using molecular dynamics simulations that some single crystal monatomic FCC metal nanowires can exhibit NTE along the length direction due to a novel thermomechanical coupling. We develop an analytic model for the CTE in nanowires that is a function of the surface stress, elastic modulus, and nanowire size. The model suggests that the CTE of nanowires can be reduced due to elastic softening of the materials and also due to surface stress. For the nanowires, the model predicts that the CTE reduction can lead to NTE if the nanowire Young's modulus is sufficiently reduced while the nanowire surface stress remains sufficiently large, which is in excellent agreement with the molecular dynamics simulation results. Overall, we find a "smaller is smaller" trend for the CTE of nanowires, leading to this unexpected, surface-stress-driven mechanism for NTE in nanoscale materials.

  13. The two-stage clonal expansion model in occupational cancer epidemiology: results from three cohort studies.

    PubMed

    Zeka, Ariana; Gore, Rebecca; Kriebel, David

    2011-08-01

    The objective of this work was to apply the two-stage clonal expansion model, with the intention to expand the literature on epidemiological applications of the model and demonstrate the feasibility of incorporating biologically based modelling methods into the widely used retrospective cohort study. The authors fitted the two-stage clonal expansion model model to three occupational cohort studies: (1) a cohort of textile workers exposed to asbestos and followed for lung cancer mortality; (2) a cohort of diatomaceous earth workers exposed to silica and also followed for lung cancer mortality; and (3) a cohort of automotive manufacturing workers exposed to straight metalworking fluid (MWF) and followed for larynx cancer incidence. The model allowed the authors to estimate exposure effects in three stages: cancer initiation (early effects), promotion or malignant transformation (late effects). In the first cohort, the authors found strong evidence for an early effect of asbestos on lung cancer risk. Findings from analyses of the second cohort suggested early and less evidently late effects of silica on lung cancer risk. In the MWF (third) cohort, there was only weak evidence of straight MWF exposure effects on both early and late stages. The authors also observed a late birth cohort effect on larynx cancer risk. The findings for asbestos and silica were essentially confirmatory, supporting evidence for their early effects on lung cancer from a large body of literature. The effect of straight MWF on larynx cancer was less clear.

  14. Dynamics of mtDNA introgression during species range expansion: insights from an experimental longitudinal study

    PubMed Central

    Mastrantonio, V.; Porretta, D.; Urbanelli, S.; Crasta, G.; Nascetti, G.

    2016-01-01

    Introgressive hybridization represents one of the long-lasting debated genetic consequences of species range expansion. Mitochondrial DNA has been shown to heavily introgress between interbreeding animal species that meet in new sympatric areas and, often, asymmetric introgression from local to the colonizing populations has been observed. Disentangling among the evolutionary and ecological processes that might shape this pattern remains difficult, because they continuously act across time and space. In this context, long-term studies can be of paramount importance. Here, we investigated the dynamics of mitochondrial introgression between two mosquito species (Aedes mariae and Ae. zammitii ) during a colonization event that started in 1986 after a translocation experiment. By analyzing 1,659 individuals across 25 years, we showed that introgression occurred earlier and at a higher frequency in the introduced than in the local species, showing a pattern of asymmetric introgression. Throughout time, introgression increased slowly in the local species, becoming reciprocal at most sites. The rare opportunity to investigate the pattern of introgression across time during a range expansion along with the characteristics of our study-system allowed us to support a role of demographic dynamics in determining the observed introgression pattern. PMID:27460445

  15. Making housing first happen: organizational leadership in VA's expansion of permanent supportive housing.

    PubMed

    Kertesz, Stefan G; Austin, Erika Laine; Holmes, Sally K; Pollio, David E; Schumacher, Joseph E; White, Bert; Lukas, Carol VanDeusen

    2014-12-01

    While most organizational literature has focused on initiatives that transpire inside the hospital walls, the redesign of American health care increasingly asks that health care institutions address matters outside their walls, targeting the health of populations. The US Department of Veterans Affairs (VA)'s national effort to end Veteran homelessness represents an externally focused organizational endeavor. Our aim was to evaluate the role of organizational practices in the implementation of Housing First (HF), an evidence-based homeless intervention for chronically homeless individuals. This was an interview-based comparative case study conducted across eight VA Medical Centers (VAMCs). Front line staff, mid-level managers, and senior leaders at VA Medical Centers were interviewed between February and December 2012. Using a structured narrative and numeric scoring, we assessed the correlation between successful HF implementation and organizational practices devised according to the organizational transformation model (OTM). Scoring results suggested a strong association between HF implementation and OTM practice. Strong impetus to house Veterans came from national leadership, reinforced by Medical Center directors closely tracking results. More effective Medical Center leaders differentiated themselves by joining front-line staff in the work (at public events and in process improvement exercises), by elevating homeless-knowledgeable persons into senior leadership, and by exerting themselves to resolve logistic challenges. Vertical alignment and horizontal integration advanced at sites that fostered work groups cutting across service lines and hierarchical levels. By contrast, weak alignment from top to bottom typically also hindered cooperation across departments. Staff commitment to ending homelessness was high, though sustainability planning was limited in this baseline year of observation. Key organizational practices correlated with more successful

  16. Matrixed business support comparison study.

    SciTech Connect

    Parsons, Josh D.

    2004-11-01

    The Matrixed Business Support Comparison Study reviewed the current matrixed Chief Financial Officer (CFO) division staff models at Sandia National Laboratories. There were two primary drivers of this analysis: (1) the increasing number of financial staff matrixed to mission customers and (2) the desire to further understand the matrix process and the opportunities and challenges it creates.

  17. Comment on "Phonemic diversity supports a serial founder effect model of language expansion from Africa".

    PubMed

    Jaeger, T Florian; Pontillo, Daniel; Graff, Peter

    2012-03-02

    Atkinson (Reports, 15 April 2011, p. 346) argues that the phonological complexity of languages reflects the loss of phonemic distinctions due to successive founder events during human migration (the serial founder hypothesis). Statistical simulations show that the type I error rate of Atkinson's analysis is hugely inflated. The data at best support only a weak interpretation of the serial founder hypothesis.

  18. Comment on "Phonemic diversity supports a serial founder effect model of language expansion from Africa".

    PubMed

    Wang, Chuan-Chao; Ding, Qi-Liang; Tao, Huan; Li, Hui

    2012-02-10

    Atkinson (Reports, 15 April 2011, p. 346) reported a declined trend of phonemic diversity from Africa that indicated the African exodus of modern languages. However, his claim was only supported when the phonemic diversities were binned into three or five levels. Analyses using raw data without simplification suggest a decline from central Asia rather than from Africa.

  19. Comment on "Phonemic diversity supports a serial founder effect model of language expansion from Africa".

    PubMed

    Cysouw, Michael; Dediu, Dan; Moran, Steven

    2012-02-10

    We show that Atkinson's (Reports, 15 April 2011, p. 346) intriguing proposal--that global linguistic diversity supports a single language origin in Africa--is an artifact of using suboptimal data, biased methodology, and unjustified assumptions. We criticize his approach using more suitable data, and we additionally provide new results suggesting a more complex scenario for the emergence of global linguistic diversity.

  20. Thermal Expansion Studies of Selected High Temperature Thermoelectric Materials

    NASA Technical Reports Server (NTRS)

    Ravi, Vilupanur; Firdosy, Samad; Caillat, Thierry; Brandon, Erik; Van Der Walde, Keith; Maricic, Lina; Sayir, Ali

    2008-01-01

    Radioisotope thermoelectric generators (RTGs) generate electrical power by converting the heat released from the nuclear decay of radioactive isotopes (typically plutonium-238) into electricity using a thermoelectric converter. RTGs have been successfully used to power a number of space missions and have demonstrated their reliability over an extended period of time (tens of years) and are compact, rugged, radiation resistant, scalable, and produce no noise, vibration or torque during operation. System conversion efficiency for state-of-practice RTGs is about 6% and specific power less than or equal to 5.1 W/kg. Higher specific power would result in more on-board power for the same RTG mass, or less RTG mass for the same on-board power. The Jet Propulsion Laboratory has been leading, under the advanced thermoelectric converter (ATEC) project, the development of new high-temperature thermoelectric materials and components for integration into advanced, more efficient RTGs. Thermoelectric materials investigated to date include skutterudites, the Yb14MnSb11 compound, and SiGe alloys. The development of long-lived thermoelectric couples based on some of these materials has been initiated and is assisted by a thermo-mechanical stress analysis to ensure that all stresses under both fabrication and operation conditions will be within yield limits for those materials. Several physical parameters are needed as input to this analysis. Among those parameters, the coefficient of thermal expansion (CTE) is critically important. Thermal expansion coefficient measurements of several thermoelectric materials under consideration for ATEC are described in this paper. The stress response at the interfaces in material stacks subjected to changes in temperature is discussed, drawing on work from the literature and project-specific tools developed here. The degree of CTE mismatch and the associated effect on the formation of stress is highlighted.

  1. Thermal Expansion Studies of Selected High-Temperature Thermoelectric Materials

    NASA Astrophysics Data System (ADS)

    Ravi, Vilupanur; Firdosy, Samad; Caillat, Thierry; Brandon, Erik; van der Walde, Keith; Maricic, Lina; Sayir, Ali

    2009-07-01

    Radioisotope thermoelectric generators (RTGs) generate electrical power by converting the heat released from the nuclear decay of radioactive isotopes (typically plutonium-238) into electricity using a thermoelectric converter. RTGs have been successfully used to power a number of space missions and have demonstrated their reliability over an extended period of time (tens of years) and are compact, rugged, radiation resistant, scalable, and produce no noise, vibration or torque during operation. System conversion efficiency for state-of-practice RTGs is about 6% and specific power ≤5.1 W/kg. A higher specific power would result in more onboard power for the same RTG mass, or less RTG mass for the same onboard power. The Jet Propulsion Laboratory has been leading, under the advanced thermoelectric converter (ATEC) project, the development of new high-temperature thermoelectric materials and components for integration into advanced, more efficient RTGs. Thermoelectric materials investigated to date include skutterudites, the Yb14MnSb11 compound, and SiGe alloys. The development of long-lived thermoelectric couples based on some of these materials has been initiated and is assisted by a thermomechanical stress analysis to ensure that all stresses under both fabrication and operation conditions will be within yield limits for those materials. Several physical parameters are needed as input to this analysis. Among those parameters, the coefficient of thermal expansion (CTE) is critically important. Thermal expansion coefficient measurements of several thermoelectric materials under consideration for ATEC are described in this paper. The stress response at the interfaces in material stacks subjected to changes in temperature is discussed, drawing on work from the literature and project-specific tools developed here. The degree of CTE mismatch and the associated effect on the formation of stress is highlighted.

  2. Support effects studied on model supported catalysts. Progress report

    SciTech Connect

    Gorte, R.J.

    1993-02-01

    Composition and structure of oxide support materials can change the catalytic behavior of metal and oxide catalysts. Model catalysts are being studied in which the active phase is deposited on flat oxide substrates, with emphasis on metals catalysis for automotive emissions control and acidity in supported oxides. Research is reported in the following areas: particle-size effects, support effects on ZnO and zirconia, support effects on ceria, supported oxides, and low energy ion scattering (no results in the latter).

  3. Simulation study of negative thermal expansion in yttrium tungstate Y2W3O12.

    PubMed

    Rimmer, Leila H N; Dove, Martin T

    2015-05-13

    A simulation study of negative thermal expansion in Y2W3O12 was carried out using calculations of phonon dispersion curves through the application of density functional perturbation theory. The mode eigenvectors were mapped onto flexibility models and results compared with calculations of the mode Grüneisen parameters. It was found that many lower-frequency phonons contribute to negative thermal expansion in Y2W3O12, all of which can be described in terms of rotations of effectively rigid WO4 tetrahedra and Y-O rods. The results are strikingly different from previous phonon studies of higher-symmetry materials that show negative thermal expansion.

  4. Structure-guided expansion of kinase fragment libraries driven by support vector machine models.

    PubMed

    Erickson, Jon A; Mader, Mary M; Watson, Ian A; Webster, Yue W; Higgs, Richard E; Bell, Michael A; Vieth, Michal

    2010-03-01

    This work outlines a new de novo design process for the creation of novel kinase inhibitor libraries. It relies on a profiling paradigm that generates a substantial amount of kinase inhibitor data from which highly predictive QSAR models can be constructed. In addition, a broad diversity of X-ray structure information is needed for binding mode prediction. This is important for scaffold and substituent site selection. Borrowing from FBDD, the process involves fragmentation of known actives, proposition of binding mode hypotheses for the fragments, and model-driven recombination using a pharmacophore derived from known kinase inhibitor structures. The support vector machine method, using Merck atom pair derived fingerprint descriptors, was used to build models from activity from 6 kinase assays. These models were qualified prospectively by selecting and testing compounds from the internal compound collection. Overall hit and enrichment rates of 82% and 2.5%, respectively, qualified the models for use in library design. Using the process, 7 novel libraries were designed, synthesized and tested against these same 6 kinases. The results showed excellent results, yielding a 92% hit rate for the 179 compounds that made up the 7 libraries. The results of one library designed to include known literature compounds, as well as an analysis of overall substituent frequency, are discussed. Copyright 2009 Elsevier B.V. All rights reserved.

  5. Impacts of road network expansion on landscape ecological risk in a megacity, China: A case study of Beijing.

    PubMed

    Mo, Wenbo; Wang, Yong; Zhang, Yingxue; Zhuang, Dafang

    2017-01-01

    Road networks affect the spatial structure of urban landscapes, and with continuous expansion, it will also exert more widespread influences on the regional ecological environment. With the support of geographic information system (GIS) technology, based on the application of various spatial analysis methods, this study analyzed the spatiotemporal changes of road networks and landscape ecological risk in the research area of Beijing to explore the impacts of road network expansion on ecological risk in the urban landscape. The results showed the following: 1) In the dynamic processes of change in the overall landscape pattern, the changing differences in landscape indices of various landscape types were obvious and were primarily related to land-use type. 2) For the changes in a time series, the expansion of the road kernel area was consistent with the extension of the sub-low-risk area in the urban center, but some differences were observed during different stages of development. 3) For the spatial position, the expanding changes in the road kernel area were consistent with the grade changes of the urban central ecological risk, primarily because both had a certain spatial correlation with the expressways. 4) The influence of road network expansion on the ecological risk in the study area had obvious spatial differences, which may be closely associated with the distribution of ecosystem types.

  6. First Lunar Outpost support study

    NASA Technical Reports Server (NTRS)

    Bartz, Christopher; Cook, John; Rusingizandekwe, Jean-Luc

    1993-01-01

    The First Lunar Outpost (FLO) is the first manned step in the accomplishment of the Space Exploration Initiative, the Vice President's directive to NASA on the 20th anniversary of the Apollo moon landing. FLO's broad objectives are the establishment of a permanent human presence on the moon, supporting the utilization of extraterrestrial resources in a long-term, sustained program. The primary objective is to emplace and validate the first elements of a man tended outpost on the lunar surface to provide the basis for: (1) establishing, maintaining and expanding human activities and influence across the surface; (2) establishing, maintaining and enhancing human safety and productivity; (3) accommodating space transportation operations to and from the surface; (4) accommodating production of scientific information; (5) exploiting in-situ resources. Secondary objectives are: (1) to conduct local, small scale science (including life science); (2) In-situ resource utilization (ISRU) demonstrations; (3) engineering and operations tests; (4) to characterize the local environment; and (5) to explore locally. The current work is part of ongoing research at the Sasakawa International Center for Space Architecture supporting NASA's First Lunar Outpost initiative. Research at SICSA supporting the First Lunar Outpost initiative has been funded through the Space Exploration Initiatives office at Johnson Space Center. The objectives of the current study are to further develop a module concept from an evaluation of volumetric and programmatic requirements, and pursue a high fidelity design of this concept, with the intention of providing a high fidelity design mockup to research planetary design issues and evaluate future design concepts.

  7. Clonal integration supports the expansion from terrestrial to aquatic environments of the amphibious stoloniferous herb Alternanthera philoxeroides.

    PubMed

    Wang, N; Yu, F-H; Li, P-X; He, W-M; Liu, J; Yu, G-L; Song, Y-B; Dong, M

    2009-05-01

    Effects of clonal integration on land plants have been extensively studied, but little is known about the role in amphibious plants that expand from terrestrial to aquatic conditions. We simulated expansion from terrestrial to aquatic habitats in the amphibious stoloniferous alien invasive alligator weed (Alternanthera philoxeroides) by growing basal ramets of clonal fragments in soils connected (allowing integration) or disconnected (preventing integration) to the apical ramets of the same fragments submerged in water to a depth of 0, 5, 10 or 15 cm. Clonal integration significantly increased growth and clonal reproduction of the apical ramets, but decreased both of these characteristics in basal ramets. Consequently, integration did not affect the performance of whole clonal fragments. We propose that alligator weed possesses a double-edged mechanism during population expansion: apical ramets in aquatic habitats can increase growth through connected basal parts in terrestrial habitats; however, once stolon connections with apical ramets are lost by external disturbance, the basal ramets in terrestrial habitats increase stolon and ramet production for rapid spreading. This may contribute greatly to the invasiveness of alligator weed and also make it very adaptable to habitats with heavy disturbance and/or highly heterogeneous resource supply.

  8. Electricity system expansion studies to consider uncertainties and interactions in restructured markets

    NASA Astrophysics Data System (ADS)

    Jin, Shan

    This dissertation concerns power system expansion planning under different market mechanisms. The thesis follows a three paper format, in which each paper emphasizes a different perspective. The first paper investigates the impact of market uncertainties on a long term centralized generation expansion planning problem. The problem is modeled as a two-stage stochastic program with uncertain fuel prices and demands, which are represented as probabilistic scenario paths in a multi-period tree. Two measurements, expected cost (EC) and Conditional Value-at-Risk (CVaR), are used to minimize, respectively, the total expected cost among scenarios and the risk of incurring high costs in unfavorable scenarios. We sample paths from the scenario tree to reduce the problem scale and determine the sufficient number of scenarios by computing confidence intervals on the objective values. The second paper studies an integrated electricity supply system including generation, transmission and fuel transportation with a restructured wholesale electricity market. This integrated system expansion problem is modeled as a bi-level program in which a centralized system expansion decision is made in the upper level and the operational decisions of multiple market participants are made in the lower level. The difficulty of solving a bi-level programming problem to global optimality is discussed and three problem relaxations obtained by reformulation are explored. The third paper solves a more realistic market-based generation and transmission expansion problem. It focuses on interactions among a centralized transmission expansion decision and decentralized generation expansion decisions. It allows each generator to make its own strategic investment and operational decisions both in response to a transmission expansion decision and in anticipation of a market price settled by an Independent System Operator (ISO) market clearing problem. The model poses a complicated tri-level structure

  9. Expansion of the MANAGE database with forest and drainage studies

    USDA-ARS?s Scientific Manuscript database

    The “Measured Annual Nutrient loads from AGricultural Environments” (MANAGE) database was published in 2006 to expand an early 1980’s compilation of nutrient export (load) data from agricultural land uses at the field or farm spatial scale. Then in 2008, MANAGE was updated with 15 additional studie...

  10. 77 FR 65895 - Announcement of the Award of Four Single-Source Program Expansion Supplement Grants To Support...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-31

    ... CONTACT: Moushumi Beltangady, Office of the Deputy Assistant Secretary for Early Childhood Development... expansion supplement grants to Tribal Maternal, Infant, and Early Childhood Home Visiting (MIECHV) grantees... expansion supplement grants to four grantees in the Tribal Maternal, Infant, and Early Childhood Home...

  11. Experimental study of penetration-cavity expansion soil bioturbation models using miniature cone penetrometers

    NASA Astrophysics Data System (ADS)

    Ruiz, Siul; Or, Dani; Schymanski, Stan

    2015-04-01

    A recently developed model of soil penetration mechanics and energetics by earthworms and plant roots is based on analogy with cone penetration and cavity expansion. Model predicted resistive forces for different geometries were tested using miniature cone penetrometers at sizes compatible with burrowing earthworms and growing roots. Experiments using cones of different radii (1.0 to 2.5 mm) and different semi-apex angles (15-300) were conducted using an apparatus enabling insertion at constant (prescribed) rates while obtaining highly resolved penetration resistance force measurements. Penetration experiments used soils at different water contents where soil mechanical parameters were determined independently using Oedometer tests under confined and unconfined conditions. Measurements were compared with predictions by analytical expressions for earthworm or root burrowing mechanics. Model predictions for the insertion force as a function of cone geometry and soil mechanical properties were in excellent agreement with cone penetration measurements. The study provides the necessary experimental confirmation to support energetic estimates of bioturbation costs in terms of soil organic carbon consumption. The study provides a better understanding of the fundamental duality nature between penetration forces and stresses and the dependency on cone angle. The measurements suggest that friction plays a relatively minor role as confirmed by experiments using recessed cones (no soil-shaft friction). Differences in application of the model to plant roots and earthworms will be discussed.

  12. Rapid-maxillary-expansion induced rhinological effects: a retrospective multicenter study.

    PubMed

    Motro, Melih; Schauseil, Michael; Ludwig, Björn; Zorkun, Berna; Mainusch, Saskia; Ateş, Mustafa; Küçükkeleş, Nazan; Korbmacher-Steiner, Heike

    2016-03-01

    Conventional dental-borne rapid maxillary expansion (RME) leads to a widening of the airways, followed by improved nasal breathing. Although combined skeletal-dental appliances are nowadays being inserted increasingly often and provide a force at the center of resistance in the nasomaxillary complex, no study exists so far that shows whether this treatment may improve the expansionary effect on the airways. In this study, low-dose computed tomography (CT) images from 31 patients (average age 14.63 ± 0.38 years) were examined retrospectively. Both records (T0 = before expansion and T1 = immediately after maximum expansion) were taken in a time interval of 25 days to avoid growth influence. Five patients were treated with Hyrax RME, 6 patients with Hybrid RME, and 20 patients with acrylic cap RME. The total airway volume increased highly significantly (mean +7272.6 mm(3); P < 0.001, power = 0.998), representing an average airway expansion of +11.54 % (2.35 %/mm activation). While the nasopharynx and oropharynx showed highly significant expansion (P < 0.000, power = 0.999), the airway at the laryngopharynx did not change significantly (P > 0.779, power = 0.05). Although the patients were significantly older in the Hybrid RME group (P = 0.006), the positive rhinological effects were comparable within all groups of different appliances (P > 0.316). Hybrid RME may, therefore, be an advisable procedure in patients with nasomaxillary impairment and pronounced patient's age.

  13. Comparative study of phonon spectrum and thermal expansion of graphene, silicene, germanene, and blue phosphorene

    NASA Astrophysics Data System (ADS)

    Ge, Xu-Jin; Yao, Kai-Lun; Lü, Jing-Tao

    2016-10-01

    Based on first-principles calculations using density functional theory, we study the vibrational properties and thermal expansion of monoatomic two-dimensional honeycomb lattices: graphene, silicene, germanene, and blue phosphorene. We focus on the similarities and differences of their properties, and try to understand them from their lattice structures. We illustrate that, from graphene to blue phosphorene, a phonon band gap develops due to large buckling-induced mixing of the in-plane and out-of-plane phonon modes. This mixing also influences their thermal properties. Using quasiharmonic approximation, we find that all of them show negative thermal expansion at room temperature.

  14. [Matrix Support: a bibliographical study].

    PubMed

    Iglesias, Alexandra; Avellar, Luziane Zacché

    2014-09-01

    This article presents a bibliographical review of matrix support in mental health. A search was conducted in the Virtual Health Library and the LILACS, SciELO and Google Scholar databases using the key words: "matrix support in mental health." Fourteen articles were located with the desired characteristics, which indicates that only a restricted number of publications are in circulation. The articles were analyzed with respect to their structural and methodological aspects, which revealed the absolute predominance of the use of qualitative methods and health professionals as the target research population. The same articles were then analyzed for their theoretical discussions. Among other issues, the importance of matrix support to enhance the primary health care teams provided to people suffering from psychic distress is highlighted. However, there is still considerable confusion regarding the proposal of the matrix support and shared responsibilities between teams of reference and mental health professionals, which emphasizes the need for training of these professionals, as well as better coordination and organization of the mental health care network.

  15. Studies of beam expansion and distributed Bragg reflector lasers for fiber optics and optical signal processing

    NASA Astrophysics Data System (ADS)

    Garmire, E. M.

    1981-03-01

    Separate studies were performed on beam expansion and on distributed Bragg Reflector (DBR) lasers preliminary to monolithic integration on GaAs substrates. These components are proposed for use in optical signal processing, for fiber optic sources and for high brightness lasers.

  16. The great human expansion.

    PubMed

    Henn, Brenna M; Cavalli-Sforza, L L; Feldman, Marcus W

    2012-10-30

    Genetic and paleoanthropological evidence is in accord that today's human population is the result of a great demic (demographic and geographic) expansion that began approximately 45,000 to 60,000 y ago in Africa and rapidly resulted in human occupation of almost all of the Earth's habitable regions. Genomic data from contemporary humans suggest that this expansion was accompanied by a continuous loss of genetic diversity, a result of what is called the "serial founder effect." In addition to genomic data, the serial founder effect model is now supported by the genetics of human parasites, morphology, and linguistics. This particular population history gave rise to the two defining features of genetic variation in humans: genomes from the substructured populations of Africa retain an exceptional number of unique variants, and there is a dramatic reduction in genetic diversity within populations living outside of Africa. These two patterns are relevant for medical genetic studies mapping genotypes to phenotypes and for inferring the power of natural selection in human history. It should be appreciated that the initial expansion and subsequent serial founder effect were determined by demographic and sociocultural factors associated with hunter-gatherer populations. How do we reconcile this major demic expansion with the population stability that followed for thousands years until the inventions of agriculture? We review advances in understanding the genetic diversity within Africa and the great human expansion out of Africa and offer hypotheses that can help to establish a more synthetic view of modern human evolution.

  17. Human platelet lysate supports ex vivo expansion and enhances osteogenic differentiation of human bone marrow-derived mesenchymal stem cells.

    PubMed

    Xia, Wenjie; Li, Hui; Wang, Zhen; Xu, Ru; Fu, Yongshui; Zhang, Xiuming; Ye, Xin; Huang, Yingfeng; Xiang, Andy Peng; Yu, Weihua

    2011-06-01

    MSCs (mesenchymal stem cells) with their versatile growth and differentiation potential are ideal candidates for use in regenerative medicine and are currently making their way into clinical trials, which requires the development of xeno-free protocols for their culture. In this study, MSCs were cultured in 10% FCS or 7.5% HPL (human platelet lysate)-supplemented media. We found that both groups of MSCs showed a comparable morphology, phenotype and proliferation. The percentage of cells in the S- and G2-/M-phases, however, was slightly up-regulated (P<0.01) in HPL group. HPL contains PDGF (platelet derived growth factor)-AB and IGF (insulin-like growth factor)-1. In addition, compared with FCS group, MSCs in HPL group showed an increase in osteogenic differentiation and a decrease in adipogenic differentiation. In conclusion, MSCs in HPL-supplemented media maintained similar growing potential and phenotype, while osteogenic potential was enhanced. HPL offers a promising alternative to FCS for MSC expansion for clinical application, especially in bone injury diseases.

  18. Magnetotail flux accumulation leading to auroral expansion and a substorm current wedge: case study

    NASA Astrophysics Data System (ADS)

    Chu, X.; McPherron, R. L.; Hsu, T. S.; Angelopoulos, V.; Weygand, J. M.; Strangeway, R. J.; Liu, J.

    2015-12-01

    Magnetotail burst busty flows, magnetic field dipolarization, and auroral poleward expansion are linked to the development of substorm current wedges (SCW). Although auroral brightening is often attributed to field-aligned currents (FACs) in the SCW produced by flow vorticity and pressure redistribution, in-situ observations addressing the mechanism that generates these currents have been scarce. Conjugate observations and modelling results utilizing magnetotail satellites, inversion technique for SCW, and auroral imagers were used to study the release, transport, and accumulation of magnetic flux by flows; dipolarization associated with substorm current wedge formation; and auroral poleward expansion during an isolated substorm on 13 February 2008. During early expansion phase, magnetic flux released by magnetic reconnection was transported by earthward flows. Some magnetic flux was accumulated in the near-Earth region, and the remainder was transported azimuthally by flow diversion. The accumulated flux created a high pressure region with vertically dipolarized and azimuthally bent magnetic field lines. The rotation of the magnetic field lines was consistent with the polarity of the SCW. In the near-Earth region, good agreement was found among the magnetic flux transported by the flows, the accumulated flux causing dipolarization inside the SCW, and the flux enclosed within the poleward-expanded auroral oval. This agreement demonstrates that magnetic flux from the flows accumulated and generated the SCW, the magnetic dipolarization, and the auroral poleward expansion. The quantity of accumulated flux appears to determine the amplitudes of these phenomena.

  19. The influence of expansion on intraoperative bone blood flow in multisegmental maxillary osteotomies: an experimental study.

    PubMed

    Kretschmer, W B; Baciut, G; Dinu, C; Baciut, M; Barbur, I; Muste, A; Dietz, K

    2010-03-01

    The aim of the presented study was to investigate the effect of maxillary expansion in multisegmental Le Fort I osteotomies on bone blood flow. Five sheep underwent a three-piece total maxillary osteotomy. Bone blood flow was measured intraoperatively by laser Doppler flowmetry in the premaxilla, the lateral segments and the mandible before osteotomy, after osteotomy and segmentation as well as after 4mm, 8mm and 12mm expansion with a Hyrax screw. A significant reduction in blood flow was seen after osteotomy and segmentation with a factor of 3.10 and between 4mm and 8mm expansion with a factor of 1.81. No significant differences could be found between 0mm and 4mm widening or between 8mm and 12mm widening. These results suggest that expansion of more than 4mm in multisegmental osteotomies enhances the risk of avascular sequelae. As greater maxillary widening has been carried out in many cases without avascular complications, further research on additional factors, influencing the recovery of perfusion, is needed.

  20. Thermal expansion in 3d-metal Prussian Blue Analogs-A survey study

    SciTech Connect

    Adak, Sourav; Daemen, Luke L.; Hartl, Monika; Williams, Darrick; Summerhill, Jennifer; Nakotte, Heinz

    2011-11-15

    We present a comprehensive study of the structural properties and the thermal expansion behavior of 17 different Prussian Blue Analogs (PBAs) with compositions M{sup II}{sub 3}[(M'){sup III}(CN){sub 6}]{sub 2}.nH{sub 2}O and M{sup II}{sub 2}[Fe{sup II}(CN){sub 6}].nH{sub 2}O, where M{sup II}=Mn, Fe, Co, Ni, Cu and Zn, (M'){sup III}=Co, Fe and n is the number of water molecules, which range from 5 to 18 for these compounds. The PBAs were synthesized via standard chemical precipitation methods, and temperature-dependent X-ray diffraction studies were performed in the temperature range between -150 deg. C (123 K) and room-temperature. The vast majority of the studied PBAs were found to crystallize in cubic structures of space groups Fm3-bar m, F4-bar 3m and Pm3-bar m. The temperature dependence of the lattice parameters was taken to compute an average coefficient of linear thermal expansion in the studied temperature range. Of the 17 compounds, 9 display negative values for the average coefficient of linear thermal expansion, which can be as large as 39.7x{sup 1}0{sup -6} K{sup -1} for Co{sub 3}[Co(CN){sub 6}]{sub 2}.12H{sub 2}O. All of the M{sup II}{sub 3}[Co{sup III}(CN){sub 6}]{sub 2}.nH{sub 2}O compounds show negative thermal expansion behavior, which correlates with the Irving-Williams series for metal complex stability. The thermal expansion behavior for the PBAs of the M{sup II}{sub 3}[Fe{sup III}(CN){sub 6}]{sub 2}.nH{sub 2}O family are found to switch between positive (for M=Mn, Co, Ni) and negative (M=Cu, Zn) behavior, depending on the choice of the metal cation (M). On the other hand, all of the M{sup II}{sub 2}[Fe{sup II}(CN){sub 6}].nH{sub 2}O compounds show positive thermal expansion behavior. - Graphical Abstract: The structure of Prussian Blue analogs (PBAs) consists of two types of metal centered octahedral units connected by cyanide ligand. Lattice and interstitial water molecules are present in these framework structures. All the PBAs of the M{sub 3

  1. Policies for Evaluation and Regulation of Higher Education in Brazil (1995-2010), Supporting the Expansion of Private Higher Education

    ERIC Educational Resources Information Center

    Barreyro, Gladys Beatriz; Rothen, José Carlos; Santana, Andréia da Cunha Malheiros

    2014-01-01

    This paper analyzes the routes of the evaluation of higher education in Brazil, from 1995 until 2010. In 1995, during Fernando Henrique Cardoso's administration, higher education began a process of expansion through private enterprise. At that time, evaluation had a key role. The focus was the evaluation of courses conducted by the Ministry of…

  2. Policies for Evaluation and Regulation of Higher Education in Brazil (1995-2010), Supporting the Expansion of Private Higher Education

    ERIC Educational Resources Information Center

    Barreyro, Gladys Beatriz; Rothen, José Carlos; Santana, Andréia da Cunha Malheiros

    2014-01-01

    This paper analyzes the routes of the evaluation of higher education in Brazil, from 1995 until 2010. In 1995, during Fernando Henrique Cardoso's administration, higher education began a process of expansion through private enterprise. At that time, evaluation had a key role. The focus was the evaluation of courses conducted by the Ministry of…

  3. The tent pole splint: a bone-supported stereolithographic surgical splint for the soft tissue matrix expansion graft procedure.

    PubMed

    Cillo, Joseph E; Theodotou, Nicholas; Samuels, Marc; Krajekian, Joseph

    2010-06-01

    This report details the use of computer-aided planning and intraoperative stereolithographic direct-bone-contact surgical splints for the accurate extraoral placement of dental implants in the soft tissue matrix expansion (tent pole) graft of the severely resorbed mandible.

  4. Ancient female philopatry, asymmetric male gene flow, and synchronous population expansion support the influence of climatic oscillations on the evolution of South American sea lion (Otaria flavescens)

    PubMed Central

    Gehara, Marcelo C. M.; Fraga, Lúcia D.; Lopes, Fernando; Túnez, Juan Ignacio; Cassini, Marcelo H.; Majluf, Patricia; Cárdenas-Alayza, Susana; Pavés, Héctor J.; Crespo, Enrique Alberto; García, Nestor; Loizaga de Castro, Rocío; Hoelzel, A. Rus; Sepúlveda, Maritza; Olavarría, Carlos; Valiati, Victor Hugo; Quiñones, Renato; Pérez-Alvarez, Maria Jose; Ott, Paulo Henrique

    2017-01-01

    The South American sea lion (Otaria flavescens) is widely distributed along the southern Atlantic and Pacific coasts of South America with a history of significant commercial exploitation. We aimed to evaluate the population genetic structure and the evolutionary history of South American sea lion along its distribution by analyses of mitochondrial DNA (mtDNA) and 10 nuclear microsatellites loci. We analyzed 147 sequences of mtDNA control region and genotyped 111 individuals of South American sea lion for 10 microsatellite loci, representing six populations (Peru, Northern Chile, Southern Chile, Uruguay (Brazil), Argentina and Falkland (Malvinas) Islands) and covering the entire distribution of the species. The mtDNA phylogeny shows that haplotypes from the two oceans comprise two very divergent clades as observed in previous studies, suggesting a long period (>1 million years) of low inter-oceanic female gene flow. Bayesian analysis of bi-parental genetic diversity supports significant (but less pronounced than mitochondrial) genetic structure between Pacific and Atlantic populations, although also suggested some inter-oceanic gene flow mediated by males. Higher male migration rates were found in the intra-oceanic population comparisons, supporting very high female philopatry in the species. Demographic analyses showed that populations from both oceans went through a large population expansion ~10,000 years ago, suggesting a very similar influence of historical environmental factors, such as the last glacial cycle, on both regions. Our results support the proposition that the Pacific and Atlantic populations of the South American sea lion should be considered distinct evolutionarily significant units, with at least two managements units in each ocean. PMID:28654647

  5. Ancient female philopatry, asymmetric male gene flow, and synchronous population expansion support the influence of climatic oscillations on the evolution of South American sea lion (Otaria flavescens).

    PubMed

    Oliveira, Larissa Rosa de; Gehara, Marcelo C M; Fraga, Lúcia D; Lopes, Fernando; Túnez, Juan Ignacio; Cassini, Marcelo H; Majluf, Patricia; Cárdenas-Alayza, Susana; Pavés, Héctor J; Crespo, Enrique Alberto; García, Nestor; Loizaga de Castro, Rocío; Hoelzel, A Rus; Sepúlveda, Maritza; Olavarría, Carlos; Valiati, Victor Hugo; Quiñones, Renato; Pérez-Alvarez, Maria Jose; Ott, Paulo Henrique; Bonatto, Sandro L

    2017-01-01

    The South American sea lion (Otaria flavescens) is widely distributed along the southern Atlantic and Pacific coasts of South America with a history of significant commercial exploitation. We aimed to evaluate the population genetic structure and the evolutionary history of South American sea lion along its distribution by analyses of mitochondrial DNA (mtDNA) and 10 nuclear microsatellites loci. We analyzed 147 sequences of mtDNA control region and genotyped 111 individuals of South American sea lion for 10 microsatellite loci, representing six populations (Peru, Northern Chile, Southern Chile, Uruguay (Brazil), Argentina and Falkland (Malvinas) Islands) and covering the entire distribution of the species. The mtDNA phylogeny shows that haplotypes from the two oceans comprise two very divergent clades as observed in previous studies, suggesting a long period (>1 million years) of low inter-oceanic female gene flow. Bayesian analysis of bi-parental genetic diversity supports significant (but less pronounced than mitochondrial) genetic structure between Pacific and Atlantic populations, although also suggested some inter-oceanic gene flow mediated by males. Higher male migration rates were found in the intra-oceanic population comparisons, supporting very high female philopatry in the species. Demographic analyses showed that populations from both oceans went through a large population expansion ~10,000 years ago, suggesting a very similar influence of historical environmental factors, such as the last glacial cycle, on both regions. Our results support the proposition that the Pacific and Atlantic populations of the South American sea lion should be considered distinct evolutionarily significant units, with at least two managements units in each ocean.

  6. A Study of Predoctoral Student Support.

    ERIC Educational Resources Information Center

    Federal Interagency Committee on Education, Washington, DC. Student Support Study Group.

    This report of the Federal Interagency Committee on Education (FCIE) presents recommendations for expanding current federal support for graduate study. Federal agencies allocated $226.2 million for predoctoral fellowships and supported some 12.9% of the full-time graduate students in the US during the 1968-1969 school year. This support increased…

  7. Performance Support Case Studies from IBM.

    ERIC Educational Resources Information Center

    Duke-Moran, Celia; Swope, Ginger; Morariu, Janis; deKam, Peter

    1999-01-01

    Presents two case studies that show how IBM addressed performance support solutions and electronic learning. The first developed a performance support and expert coaching solution; the second applied performance support to reducing implementation time and total cost of ownership of enterprise resource planning systems. (Author/LRW)

  8. Optimization of cGMP purification and expansion of umbilical cord blood-derived T-regulatory cells in support of first-in-human clinical trials.

    PubMed

    McKenna, David H; Sumstad, Darin; Kadidlo, Diane M; Batdorf, Bjorn; Lord, Colin J; Merkel, Sarah C; Koellner, Christine M; Curtsinger, Julie M; June, Carl H; Riley, James L; Levine, Bruce L; Miller, Jeffrey S; Brunstein, Claudio G; Wagner, John E; Blazar, Bruce R; Hippen, Keli L

    2017-02-01

    Thymic-derived regulatory T cells (tTreg) are critical regulators of the immune system. Adoptive tTreg transfer is a curative therapy for murine models of autoimmunity, graft rejection, and graft-versus-host disease (GVHD). We previously completed a "first-in-human" clinical trial using in vitro expanded umbilical cord blood (UCB)-derived tTreg to prevent GVHD in patients undergoing UCB hematopoietic stem cell transplantation (HSCT). tTreg were safe and demonstrated clinical efficacy, but low yield prevented further dose escalation. To optimize yield, we investigated the use of KT64/86 artificial antigen presenting cells (aAPCs) to expand tTreg and incorporated a single re-stimulation after day 12 in expansion culture. aAPCs increased UCB tTreg expansion greater than eightfold over CD3/28 stimulation. Re-stimulation with aAPCs increased UCB tTreg expansion an additional 20- to 30-fold. Re-stimulated human UCB tTreg ameliorated GVHD disease in a xenogeneic model. Following current Good Manufacturing Practice (cGMP) validation, a trial was conducted with tTreg. tTreg doses up to >30-fold higher compared with that obtained with anti-CD3/28 mAb coated-bead expansion and Foxp3 expression was stable during in vitro expansion and following transfer to patients. Increased expansion did not result in a senescent phenotype and GVHD was significantly reduced. Expansion culture with cGMP aAPCs and re-stimulation reproducibly generates sufficient numbers of UCB tTreg that exceeds the numbers of T effector cells in an UCB graft. The methodology supports future tTreg banking and is adaptable to tTreg expansion from HSC sources. Furthermore, because human leukocyte antigen matching is not required, allogeneic UCB tTreg may be a useful strategy for prevention of organ rejection and autoimmune disease. Copyright © 2017 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

  9. Millisecond dynamics of thermal expansion of mechanically controllable break junction electrodes studied in the tunneling regime

    NASA Astrophysics Data System (ADS)

    Kolesnychenko, O. Yu.; Toonen, A. J.; Shklyarevskii, O. I.; van Kempen, H.

    2001-10-01

    The thermal expansion dynamics of W, Pt-Ir, and Au mechanically controllable break junction electrodes was studied in the millisecond range. By measuring a transient tunnel current as a function of time, we found that, at low temperatures, the electrode elongation Δs˜t1/2 due to the large values of thermal diffusivity of metals. The magnitude of Δs varies in direct proportion to the power P dissipated in the electrodes.

  10. Studies of Beam Expansion and Distributed Bragg Reflector Lasers for Fiber Optics and Optical Signal Processing.

    DTIC Science & Technology

    1981-03-03

    block number) Separate studies were performed on beam expansion and on Distributed Bragg Reflector ( DBR ) lasers preliminary to monolithic integration on...Reflector ( DBR ) laser is a light source compatible with monolithic integrated optics. In the DBR laser one or both cleaved endfaces of a typical double...cleave as a laser cavity mirror. The DBR laser can be used as an integrated optics light source for integrated optical circuits. In this report we

  11. The Arabidopsis thaliana hypocotyl, a model to identify and study control mechanisms of cellular expansion.

    PubMed

    Boron, Agnieszka Karolina; Vissenberg, Kris

    2014-05-01

    Developmental biology studies in general benefit from model organisms that are well characterized. Arabidopsis thaliana fulfills this criterion and represents one of the best experimental systems to study developmental processes in higher plants. Light is a crucial factor that drives photosynthesis, but that also regulates plant morphogenesis. As the hypocotyl is completely embryonic of origin, its growth occurs solely by expansion of the cells and this process is strongly dependent on the light conditions. In this review, we provide evidence that the hypocotyl serves as ideal model object to study cell expansion mechanisms and its regulation. We focus on the regulation of hypocotyl development by light and highlight the key modulating proteins in this signaling cascade. Downstream of light-signaling, cellular expansion is greatly dependent on specific cell wall depositions, which is related to cortical microtubular (re)arrangements and on composition and/or extensibility of the cell wall. We discuss possible further experimental approaches to broaden our knowledge on hypocotyl development, which will give an outlook on the probable evolution of the field.

  12. Aerosol backscatter studies supporting LAWS

    NASA Technical Reports Server (NTRS)

    Rothermel, Jeffry

    1989-01-01

    Optimized Royal Signals and Radar Establishment (RSRE), Laser True Airspeed System (LATAS) algorithm for low backscatter conditions was developed. The algorithm converts backscatter intensity measurements from focused continuous-wave (CW) airborne Doppler lidar into backscatter coefficients. The performance of optimized algorithm under marginal backscatter signal conditions was evaluated. The 10.6 micron CO2 aerosol backscatter climatologies were statistically analyzed. Climatologies reveal clean background aerosol mode near 10(exp -10)/kg/sq m/sr (mixing ratio units) through middle and upper troposhere, convective mode associated with planetary boundary layer convective activity, and stratospheric mode associated with volcanically-generated aerosols. Properties of clean background mode are critical to design and simulation studies of Laser Atmospheric Wind Sounder (LAWS), a MSFC facility Instrument on the Earth Observing System (Eos). Previous intercomparisons suggested correlation between aerosol backscatter at CO2 wavelength and water vapor. Field measurements of backscatter profiles with MSFC ground-based Doppler lidar system (GBDLS) were initiated in late FY-88 to coincide with independent program of local rawinsonde releases and overflights by Multi-spectral Atmospheric Mapping Sensor (MAMS), a multi-channel infrared radiometer capable of measuring horizontal and vertical moisture distributions. Design and performance simulation studies for LAWS would benefit from the existence of a relationship between backscatter and water vapor.

  13. STS Case Study Development Support

    NASA Technical Reports Server (NTRS)

    Rosa de Jesus, Dan A.; Johnson, Grace K.

    2013-01-01

    The Shuttle Case Study Collection (SCSC) has been developed using lessons learned documented by NASA engineers, analysts, and contractors. The SCSC provides educators with a new tool to teach real-world engineering processes with the goal of providing unique educational materials that enhance critical thinking, decision-making and problem-solving skills. During this third phase of the project, responsibilities included: the revision of the Hyper Text Markup Language (HTML) source code to ensure all pages follow World Wide Web Consortium (W3C) standards, and the addition and edition of website content, including text, documents, and images. Basic HTML knowledge was required, as was basic knowledge of photo editing software, and training to learn how to use NASA's Content Management System for website design. The outcome of this project was its release to the public.

  14. Experimental study of flow reattachment in a single-sided sudden expansion

    NASA Technical Reports Server (NTRS)

    Westphal, R. V.; Johnston, J. P.; Eaton, J. K.

    1984-01-01

    The reattachment of a fully turbulent, two dimensional, separated shear layer downstream of a single-sided sudden expansion in a planar duct flow was examined experimentally. The importance of changing the structure of the separated shear layer on the reattachment process itself was examined. For all cases, the Reynolds number based on step height was greater than 20,000, the expansion ratio was 5/3, and the inlet boundary layer was less than one-half step height in thickness. A crucially important phase was the development of a pulsed wall probe for measurement of skin friction in the reattachment region, thus providing an unambiguous definition of the reattachment length. Quantitative features of reattachment - including streamwise development of the mean and fluctuating velocity field, pressure rise, and skin friction - were found to be similar for all cases studied when scaled by the reattachment length. A definition of the reattachment zone is proposed.

  15. Study of polytropic exponent based on high pressure switching expansion reduction

    NASA Astrophysics Data System (ADS)

    Wang, Xuanyin; Luo, Yuxi; Xu, Zhipeng

    2011-10-01

    Switching expansion reduction (SER) uses a switch valve to substitute the throttle valve to reduce pressure for high pressure pneumatics. The experiments indicate that the simulation model well predicts the actual characteristics. The heat transfers and polytropic exponents of the air in expansion tank and supply tanks of SER have been studied on the basis of the experiments and the simulation model. Through the mathematical reasoning in this paper, the polytropic exponent can be calculated by the air mass, heat, and work exchanges of the pneumatic container. For the air in a constant volume tank, when the heat-absorption is large enough to raise air temperature in discharging process, the polytropic exponent is less than 1; when the air is experiencing a discharging and heat-releasing process, the polytropic exponent exceeds the specific heat ratio (the value of 1.4).

  16. First-principles study on negative thermal expansion of PbTiO3

    NASA Astrophysics Data System (ADS)

    Wang, Fangfang; Xie, Ying; Chen, Jun; Fu, Honggang; Xing, Xianran

    2013-11-01

    It is well known that perovskite-type PbTiO3 behaves negative thermal expansion in a wide temperature range from room temperature to Curie temperature (763 K). The present study reports the first-principles study of the anisotropic thermal expansion of PbTiO3, in the framework of the density-functional theory and the density-functional perturbation theory. The curve of temperature dependence of the unit cell volume is presented from 20 to 520 K through the calculation of the minimum of total free energy at each temperature point. The negative thermal expansion of PbTiO3 is calculated without empirical parameters. Furthermore, the distinctive thermodynamic act of PbTiO3 from expanding to contracting at tetragonal phase is reproduced. The ab-initio calculations reveal that this unique appearance depends on the phonon vibration. The dynamical contributions of various atoms are also calculated to account for the disparate role of Pb-O and Ti-O bond.

  17. First-principles study on negative thermal expansion of PbTiO{sub 3}

    SciTech Connect

    Wang, Fangfang; Chen, Jun; Xing, Xianran; Xie, Ying; Fu, Honggang

    2013-11-25

    It is well known that perovskite-type PbTiO{sub 3} behaves negative thermal expansion in a wide temperature range from room temperature to Curie temperature (763 K). The present study reports the first-principles study of the anisotropic thermal expansion of PbTiO{sub 3}, in the framework of the density-functional theory and the density-functional perturbation theory. The curve of temperature dependence of the unit cell volume is presented from 20 to 520 K through the calculation of the minimum of total free energy at each temperature point. The negative thermal expansion of PbTiO{sub 3} is calculated without empirical parameters. Furthermore, the distinctive thermodynamic act of PbTiO{sub 3} from expanding to contracting at tetragonal phase is reproduced. The ab-initio calculations reveal that this unique appearance depends on the phonon vibration. The dynamical contributions of various atoms are also calculated to account for the disparate role of Pb-O and Ti-O bond.

  18. In vitro generated Th17 cells support the expansion and phenotypic stability of CD4(+)Foxp3(+) regulatory T cells in vivo.

    PubMed

    Zhou, Qiong; Hu, Ya; Howard, O M Zack; Oppenheim, Joost J; Chen, Xin

    2014-01-01

    CD4(+) T cells stimulate immune responses through distinct patterns of cytokine produced by Th1, Th2 or Th17 cells, or inhibit immune responses through Foxp3-expressing regulatory T cells (Tregs). Paradoxically, effector T cells were recently shown to activate Tregs, however, it remains unclear which Th subset is responsible for this effect. In this study, we found that Th17 cells expressed the highest levels of TNF among in vitro generated Th subsets, and most potently promoted expansion and stabilized Foxp3 expression by Tregs when co-transferred into Rag1(-/-) mice. Both TNF and IL-2 produced by Th17 cells contributed to this effect. The stimulatory effect of Th17 cells on Tregs was largely abolished when co-transferred with TNFR2-deficient Tregs. Furthermore, Tregs deficient in TNFR2 also supported a much lower production of IL-17A and TNF expression by co-transferred Th17 cells. Thus, our data indicate that the TNF-TNFR2 pathway plays a crucial role in the reciprocal stimulatory effect of Th17 cells and Tregs. This bidirectional interaction should be taken into account when designing therapy targeting Th17 cells, Tregs, TNF and TNFR2.

  19. In vitro generated Th17 cells support the expansion and phenotypic stability of CD4+ Foxp3+ Regulatory T cells in vivo

    PubMed Central

    Zhou, Qiong; Hu, Ya; Howard, O.M. Zack; Oppenheim, Joost J.; Chen, Xin

    2013-01-01

    CD4+ T cells stimulate immune responses through distinct patterns of cytokine produced by Th1, Th2 or Th17 cells, or inhibit immune responses through Foxp3-expressing regulatory T cells (Tregs). Paradoxically, effector T cells were recently shown to activate Tregs, however, it remains unclear which Th subset is responsible for this effect. In this study, we found that Th17 cells expressed the highest levels of TNF among in vitro generated Th subsets, and most potently promoted expansion and stabilized Foxp3 expression by Tregs when co-transferred into Rag1−/− mice. Both TNF and IL-2 produced by Th17 cells contributed to this effect. The stimulatory effect of Th17 cells on Tregs was largely abolished when co-transferred with TNFR2-deficient Tregs. Furthermore, Tregs deficient in TNFR2 also supported a much lower production of IL-17A and TNF expression by co-transferred Th17 cells. Thus, our data indicate that the TNF-TNFR2 pathway plays a crucial role in the reciprocal stimulatory effect of Th17 cells and Tregs. This bidirectional interaction should be taken into account when designing therapy targeting Th17 cells, Tregs, TNF and TNFR2. PMID:24080164

  20. Negative thermal expansion properties in tetragonal NbPO5 from the first principles studies

    NASA Astrophysics Data System (ADS)

    Li, Tao; Fu, Xiaonan; Chang, Dahu; Sun, Qiang; Wang, Fei

    2017-03-01

    By using the first-principles calculations based on density functional theory combined with quasi-harmonic approximation, we have studied the geometric structural, thermal properties, and the negative thermal expansion (NTE) properties of tetrahedral NbPO5. The variations of cell parameter and cell volume of tetrahedral NbPO5 with temperature show that it displays NTE behavior in the range of 473-800 K along a-axis and the corresponding average coefficient of thermal expansion (CTE) is approximately -0.766 ×10-6 K-1, while the c cell parameter and the cell volume display positive thermal expansion behaviors. These results are in consistent well with the experiment observations. Further vibrational modes analysis, together with Grüneisen parameters calculations, revealed that the transverse vibration of O corner atoms accompanying the rocking motions of corner-shared NbO6 octahedron and PO4 tetrahedron dominate the negative thermal properties of tetrahedral NbPO5. Our findings will provide an understanding for the underlying mechanisms of the NTE in oxides materials.

  1. Ground-based studies of ionospheric convection associated with substorm expansion

    NASA Technical Reports Server (NTRS)

    Kamide, Y.; Richmond, A. D.; Emery, B. A.; Hutchins, C. F.; Ahn, B.-H.; De La Beaujardiere, O.; Foster, J. C.; Heelis, R. A.; Kroehl, H. W.; Rich, F. J.

    1994-01-01

    The instantaneous patterns of electric fields and currents in the high-latitude ionosphere are deduced by combining satellite and radar measurements of the ionospheric drift velocity, along with ground-based magnetometer observations for October 25, 1981. The period under study was characterized by a relatively stable southward interplanetary magnetic field (IMF), so that the obtained electric field patterns do reflect, in general, the state of sustained and enhanced plasma convection in the magnetosphere. During one of the satellite passes, however, an intense westward electrojet caused by a substorm intruded into the satellite (DE2) and radar (Chatanika, Alaska) field of view in the premidnight sector, providing a unique opportunity to differentiate the enhanced convection and substorm expansion fields. The distributions of the calculated electric potential for the expansion and maximum phases of the substorm show the first clear evidence of the coexistence of two physically different systems in the global convection pattern. The changes in the convection pattern during the substorm indicate that the large-scale potential distributions are indeed of general two-cell patterns representing the southward IMF status, but the night-morning cell has two positive peaks, one in the midnight sector and the other in the late morning hours, corresponding to the substorm expansion and the convection enhancement, respectively.

  2. Analyzing suitability for urban expansion under rapid coastal urbanization with remote sensing and GIS techniques: a case study of Lianyungang, China

    NASA Astrophysics Data System (ADS)

    Zhao, Wenjun; Zhu, Xiaodong; Reenberg, Anette; Sun, Xiang

    2010-10-01

    Beginning in 2000, Lianyungang's urbanization entered a period of rapid growth, spatially as well as economically. Rapid and intensive expansion of "construction land" imposed increasing pressures on regional environment. With the support of remote sensing data and GIS tools, this paper reports a "present-capacity-potential" integrated suitability analysis framework, in order to characterize and evaluate the suitability of urban expansion in Lianyungang. We found that during the rapid coastal urbanization process from 2000 to 2008, the characteristics of physical expansion in the study area were characterized by a combination of high-density expansion and sprawling development. The land use conversion driven by urbanization and industrialization has not occurred only in city districts, but also the surrounding areas that were spatially absorbed by urban growth, while closely associated and greatly influenced by the explosive growth of industrial establishment. The over-consumption of land resources in the areas with low environmental carrying capacity, particularly in the eastern coastal area, should be strictly controlled. Compared to conventional land suitability analysis methods, the proposed integrated approach could better review the potential environmental impacts of urban expansion and provide guidance for decision makers.

  3. Laboratory study of the expansion of a three-dimensional dusty plasma

    NASA Astrophysics Data System (ADS)

    Meyer, John K.; Merlino, Robert L.

    2013-10-01

    The expansion of a three-dimensional dusty plasma was investigated using fast video imaging and particle tracking techniques. The dust suspension was initially trapped in the electrostatic potential formed by an L-shaped grid in a glow discharge plasma. The discharge was formed in argon at a neutral pressure of 125 mtorr at a discharge current of 5 mA. A 3 mT uniform magnetic field was also present. The dust was spherical glass particles of 1 micron diameter, with an initial density on the order of 104 cm-3. The electron temperature was 2.5 eV, and the estimated dust charge was -2000 e. The initially confined dust cloud had a volume on the order of 1-2 cm3. The expansion of the dust cloud was initiated when the confining potential was removed by suddenly switching the bias on the grid to the floating condition. Measurements of the time history of the particle velocities and dust density within the expanding cloud will be presented. Work supported by DOE and NSF.

  4. Does rapid maxillary expansion affect nasopharyngeal airway? A prospective Cone Beam Computerised Tomography (CBCT) based study.

    PubMed

    Almuzian, Mohammed; Ju, Xiangyang; Almukhtar, Anas; Ayoub, Ashraf; Al-Muzian, Lubna; McDonald, Jim P

    2016-01-27

    There is limited literature discussing the three dimnesional (3D) impact of rapid maxillary expansion (RME) on upper airway. The purpose of this prospective Cone Beam Computerised Tomography (CBCT) based study is to assess the immediate 3D effects and to correlate the volumteric changes in the upper naspharyngeal airway spaces secondary to RME. Seventeen participants (8 male, 9 female, with a mean age of 12.6 ± 1.8 years), who required RME for the management of narrow maxillary arch, were recruited for this study. The prescribed expansion regimen was quarter turn (0.25 mm), twice a day until over-expansion was achieved. The mean period for the active phase was 14 days with a range of 12-21 days. Pretreatment (T1) and immediate post-expansion (T2) CBCT images were obtained and then processed using ITK snap and OnDemand3D softwar packages. Paired t-test and Interclass Correlation Coefficient (ICC) were used to assess the reproducibility of the measurements, student t-test (P < 0.05) and Pearson Correlation Coefficient (PCC) were applied to evaluate the volumetric changes in the nasopharyngeal airway spaces, linear dentolaveolar changes and correlate these changes. Though, the data of one patient was excluded from the study, owing to major differences (>5 degrees) in the head and neck posture between T1 and T2 CBCT scans, the study' findings shows that bonded RME is an effective dentoalveolar expander in growing patients (P= 0.01) with an average expansion of 3.7 mm and 2.8 mm in males and females respectively. Likewise, the upper nasopharynx (UNP) expanded significantly (15.2% in males and 12% in females). In comparison, the upper retropalatal space (URP) was significantly reduced, by almost one sixth of its original volume, more in males than females, 11.2% and 2.8% respectively. A strong direct correlation between the maxillary sinus volumetric changes, and between appliance expansion and dentoalveolar expansion were evident (PCC = 0.86, 0

  5. Study of non-contact measurement of the thermal expansion coefficients of materials based on laser feedback interferometry

    SciTech Connect

    Zheng, Fasong; Tan, Yidong; Zhang, Shulian; Lin, Jing; Ding, Yingchun

    2015-04-15

    The noncooperative and ultrahigh sensitive length measurement approach is of great significance to the study of a high-precision thermal expansion coefficient (TEC) determination of materials at a wide temperature range. The novel approach is presented in this paper based on the Nd:YAG microchip laser feedback interferometry with 1064 nm wavelength, the beam frequency of which is shifted by a pair of acousto-optic modulators and then the heterodyne phase measurement technique is used. The sample is placed in a muffle furnace with two coaxial holes opened on the opposite furnace walls. The measurement beams are perpendicular and coaxial on each surface of the sample, the configuration which can not only achieve the length measurement of sample but also eliminate the influence of the distortion of the sample supporter. The reference beams inject on the reference mirrors which are put as possible as near the holes, respectively, to eliminate the air disturbances and the influence of thermal lens effect out of the furnace chamber. For validation, the thermal expansion coefficients of aluminum and steel 45 samples are measured from room temperature to 748 K, which proved measurement repeatability of TECs is better than 0.6 × 10{sup −6}(K{sup −1}) at the range of 298 K–598 K and the high-sensitive non-contact measurement of the low reflectivity surface induced by the oxidization of the samples at the range of 598 K–748 K.

  6. The great human expansion

    PubMed Central

    Henn, Brenna M.; Cavalli-Sforza, L. L.; Feldman, Marcus W.

    2012-01-01

    Genetic and paleoanthropological evidence is in accord that today’s human population is the result of a great demic (demographic and geographic) expansion that began approximately 45,000 to 60,000 y ago in Africa and rapidly resulted in human occupation of almost all of the Earth’s habitable regions. Genomic data from contemporary humans suggest that this expansion was accompanied by a continuous loss of genetic diversity, a result of what is called the “serial founder effect.” In addition to genomic data, the serial founder effect model is now supported by the genetics of human parasites, morphology, and linguistics. This particular population history gave rise to the two defining features of genetic variation in humans: genomes from the substructured populations of Africa retain an exceptional number of unique variants, and there is a dramatic reduction in genetic diversity within populations living outside of Africa. These two patterns are relevant for medical genetic studies mapping genotypes to phenotypes and for inferring the power of natural selection in human history. It should be appreciated that the initial expansion and subsequent serial founder effect were determined by demographic and sociocultural factors associated with hunter-gatherer populations. How do we reconcile this major demic expansion with the population stability that followed for thousands years until the inventions of agriculture? We review advances in understanding the genetic diversity within Africa and the great human expansion out of Africa and offer hypotheses that can help to establish a more synthetic view of modern human evolution. PMID:23077256

  7. Anomalous components of supercooled water expansivity, compressibility, and heat capacity (Cp and Cv) from binary formamide+water solution studies

    NASA Astrophysics Data System (ADS)

    Oguni, M.; Angell, C. A.

    1983-06-01

    Recently reported heat capacity studies of N2H4+H2O and H2O2+H2O solutions, from which an anomalous component of the pure water behavior could be extracted by extrapolation, have been extended to a system NH2CHO+H2O which has the chemical stability needed to permit expansivity and compressibility measurements as well. Data accurate to ±2% for each of these properties as well as for the heat capacity are reported. The expansivity data support almost quantitatively an earlier speculative separation of the bulk and supercooled water expansivity into a ``normal'' (or ``background'') part and an ``anomalous'' part, the latter part fitting a critical law αanom=A(T/Ts-1)-γ with exponent γ=1.0. According to the present analysis, the anomalous part of the expansivity which is always negative, yields Ts in the range 225-228, γ in the range 1.28-1.0, depending on the choice of background extrapolation function. The normal contribution to the heat capacity obtained from the present work is intermediate in character to that from the previous two systems and leads to similar equation parameters. The normal contribution to the compressibility on the other hand is very different from that speculated earlier by Kanno and Angell and approximately verified by Conde et al. for ethanol-water solutions. The background component from the present analysis is ˜50% larger, with the result that the anomalous component, at least when values above 0 °C are included in the analysis, cannot be sensibly fitted to the critical point equation. The possible origin and interest content of these differences is discussed. Combination of the new thermodynamic data permit estimation of Cv values for the solution, and by extrapolation, a normal Cv component for water. The anomalous component of Cv for pure water obtained by difference has the form of a Shottky anomaly in contrast with the corresponding Cp component which diverges.

  8. A numerical study of planar and axially-symmetric sudden expansion flows

    NASA Astrophysics Data System (ADS)

    Napolitano, M.; Cinnella, P.

    The present study is concerned with the numerical prediction of planar and axially symmetric sudden expansion flows, using the Navier-Stokes as well as the boundary-layer equations. The vorticity/steam-function Navier-Stokes equations are solved by means of a robust multigrid block-line-Gauss-Seidel method. The corresponding boundary-layer equations are solved at every longitudinal station by means of an incremental block-implicit scheme, using the Newton method combined with a deferred correction strategy to achieve fast convergence on the nonlinear terms. Accurate solutions are obtained.

  9. Decellularized extracellular matrices produced from immortal cell lines derived from different parts of the placenta support primary mesenchymal stem cell expansion

    PubMed Central

    Kusuma, Gina D.; Brennecke, Shaun P.; O’Connor, Andrea J.; Kalionis, Bill

    2017-01-01

    Mesenchymal stem/stromal cells (MSCs) exhibit undesired phenotypic changes during ex vivo expansion, limiting production of the large quantities of high quality primary MSCs needed for both basic research and cell therapies. Primary MSCs retain many desired MSC properties including proliferative capacity and differentiation potential when expanded on decellularized extracellular matrix (dECM) prepared from primary MSCs. However, the need to use low passage number primary MSCs (passage 3 or lower) to produce the dECM drastically limits the utility and impact of this technology. Here, we report that primary MSCs expanded on dECM prepared from high passage number (passage 25) human telomerase reverse transcriptase (hTERT) transduced immortal MSC cell lines also exhibit increased proliferation and osteogenic differentiation. Two hTERT-transduced placenta-derived MSC cell lines, CMSC29 and DMSC23 [derived from placental chorionic villi (CMSCs) and decidua basalis (DMSCs), respectively], were used to prepare dECM-coated substrates. These dECM substrates showed structural and biochemical differences. Primary DMSCs cultured on dECM-DMSC23 showed a three-fold increase in cell number after 14 days expansion in culture and increased osteogenic differentiation compared with controls. Primary CMSCs cultured on the dECM-DMSC23 exhibited a two-fold increase in cell number and increased osteogenic differentiation. We conclude that immortal MSC cell lines derived from different parts of the placenta produce dECM with varying abilities for supporting increased primary MSC expansion while maintaining important primary MSC properties. Additionally, this is the first demonstration of using high passage number cells to produce dECM that can promote primary MSC expansion, and this advancement greatly increases the feasibility and applicability of dECM-based technologies. PMID:28152107

  10. Quantitative study on the hygroscopic expansion of spurr resin to obtain a high-resolution atlas of the mouse brain.

    PubMed

    Wang, Qingdi; Li, Anan; Gong, Hui; Xu, Dongli; Luo, Qingming

    2012-10-01

    Ultra-thin section-based microscopic imaging is considered one of the most realistic techniques for determining fine architectures of a brain-wide neural network. In this kind of method, the sample is usually embedded in resin and then immersed in water for sectioning and imaging. The effect of resin hygroscopic expansion on data accuracy and integrity is important as it may lead to inconsistent image qualities or degeneration of sectioning properties. But few studies have been conducted on this issue. Here, we have used surface profile measurements combined with sectioning and imaging by micro-optical sectioning tomography (MOST) to quantitatively study the sectioned surface expansion of spurr resin blocks as a result of water immersion for a short time period. The expansion effect on MOST imaging is also presented. The results revealed significant differences in the surface expansion of pure resin blocks with different immersion time durations (P < 0.001). During an eight-minute immersion, the surface expansion of the experimental specimens exhibited an approximately linear increase with immersion duration, while MOST images suffered a correlated decrease in brightness. Expansion was restricted to the submicron level with immersion duration of four minutes or less, and the mean and standard deviation of the expansion measurements both reached a maximum at eight minutes. When the immersion duration exceeded eight minutes, the expansion value decreased, which was most likely related to the degeneration of mechanical properties of the resin material on the block surface. This study indicates that it is necessary to select a specific sectioning mode according to the hygroscopic expansion properties of resin materials for maintaining the accuracy and integrity of whole brain atlas data.

  11. Lunar Outpost Life Support Trade Studies

    NASA Astrophysics Data System (ADS)

    Ewert, Michael; Barta, Daniel J.; Lange, Kevin; Anderson, Molly

    Engineering trade-off studies of life support system architecture and technology options were conducted for potential lunar surface mission scenarios within NASA's Constellation Program. The scenarios investigated are based largely on results of the NASA Lunar Architecture Team (LAT) Phase II study. In particular, the possibility of "Hosted Sortie" missions, the high cost of power during eclipse periods, and the potential to reduce life support consumables through scavenging, in-situ resources, and alternative EVA technologies were all examined. These trade studies were performed within the Systems Integration, Modeling and Analysis (SIMA) element of NASA's Exploration Life Support (ELS) technology development project. The tools and methodology used in the study are described briefly, followed by a discussion of mission scenarios, life support technology options and results presented in terms of "equivalent system mass" for various regenerative life support technologies and architectures. Three classes of repeated or extended lunar surface missions were investigated in this study along with several life support resource scenarios for each mission class. Individual mission durations of 14 days, 90 days and 180 days were considered with 10 missions assumed for each at a rate of 2 missions per year. The 14-day missions represent a class of "Hosted Sortie" missions where a pre-deployed and potentially mobile habitat provides life support for multiple crews at one or more locations. The 90-day and 180-day missions represent lunar outpost expeditions with a larger fixed habitat. The 180-day missions assume continuous human presence and must provide life support through eclipse periods of up to 122 hours while the 90-day missions are planned for best-case periods of nearly continuous sunlight. This paper investigates system optimization within the assumptions of each scenario and addresses how the scenario selected drives the life support system to different designs

  12. Lunar Outpost Life Support Trade Studies

    NASA Technical Reports Server (NTRS)

    Lange, Kevin E.; Anderson, Molly S.; Ewert, Michael K.; Barta, Daniel J.

    2008-01-01

    Engineering trade-off studies of life support system architecture and technology options were conducted for potential lunar surface mission scenarios within NASA's Constellation Program. The scenarios investigated are based largely on results of the NASA Lunar Architecture Team (LAT) Phase II study. In particular, the possibility of Hosted Sortie missions, the high cost of power during eclipse periods, and the potential to reduce life support consumables through scavenging, in-situ resources, and alternative EVA technologies were all examined. These trade studies were performed within the Systems Integration, Modeling and Analysis (SIMA) element of NASA's Exploration Life Support (ELS) technology development project. The tools and methodology used in the study are described briefly, followed by a discussion of mission scenarios, life support technology options and results presented in terms of equivalent system mass for various regenerative life support technologies and architectures. Three classes of repeated or extended lunar surface missions were investigated in this study along with several life support resource scenarios for each mission class. Individual mission durations of 14 days, 90 days and 180 days were considered with 10 missions assumed for each at a rate of 2 missions per year. The 14-day missions represent a class of Hosted Sortie missions where a pre-deployed and potentially mobile habitat provides life support for multiple crews at one or more locations. The 90-day and 180-day missions represent lunar outpost expeditions with a larger fixed habitat. The 180-day missions assume continuous human presence and must provide life support through eclipse periods of up to 122 hours while the 90-day missions are planned for best-case periods of nearly continuous sunlight. This paper investigates system optimization within the assumptions of each scenario and addresses how the scenario selected drives the life support system to different designs

  13. Lunar Outpost Life Support Trade Studies

    NASA Technical Reports Server (NTRS)

    Lange, Kevin E.; Anderson, Molly S.; Ewert, Michael K.; Barta, Daniel J.

    2008-01-01

    Engineering trade-off studies of life support system architecture and technology options were conducted for potential lunar surface mission scenarios within NASA's Constellation Program. The scenarios investigated are based largely on results of the NASA Lunar Architecture Team (LAT) Phase II study. In particular, the possibility of Hosted Sortie missions, the high cost of power during eclipse periods, and the potential to reduce life support consumables through scavenging, in-situ resources, and alternative EVA technologies were all examined. These trade studies were performed within the Systems Integration, Modeling and Analysis (SIMA) element of NASA's Exploration Life Support (ELS) technology development project. The tools and methodology used in the study are described briefly, followed by a discussion of mission scenarios, life support technology options and results presented in terms of equivalent system mass for various regenerative life support technologies and architectures. Three classes of repeated or extended lunar surface missions were investigated in this study along with several life support resource scenarios for each mission class. Individual mission durations of 14 days, 90 days and 180 days were considered with 10 missions assumed for each at a rate of 2 missions per year. The 14-day missions represent a class of Hosted Sortie missions where a pre-deployed and potentially mobile habitat provides life support for multiple crews at one or more locations. The 90-day and 180-day missions represent lunar outpost expeditions with a larger fixed habitat. The 180-day missions assume continuous human presence and must provide life support through eclipse periods of up to 122 hours while the 90-day missions are planned for best-case periods of nearly continuous sunlight. This paper investigates system optimization within the assumptions of each scenario and addresses how the scenario selected drives the life support system to different designs

  14. Experimental study of rotating Hagen-Poiseuille flow discharging into a 1:8 sudden expansion

    NASA Astrophysics Data System (ADS)

    Miranda-Barea, A.; Martínez-Arias, B.; Parras, L.; Burgos, M. A.; del Pino, C.

    2015-03-01

    In this paper, we present experimental evidence for the five different states that result from rotating Hagen-Poiseuille flow when it discharges into a 1:8 sudden expansion, namely: stable, convectively unstable, unstable shear layer, stable and unstable vortex breakdowns. Sanmiguel-Rojas et al. ["Three-dimensional structure of confined swirling jets at moderately large Reynolds numbers," Phys. Fluids 20, 044104 (2008)] numerically predicted four of these five states and mapped the transition from one state to another. Our main objective is to study the onset of instabilities and vortex breakdown in these states experimentally. For this purpose, we visualize the flow at the inlet of the expansion for several values of moderately large Reynolds numbers, Re, and of swirl parameters, S. We analyze the inner region of the state that corresponds to the unstable shear layer in the sudden expansion and find two different states that share the same character, although they have different non-dimensional frequencies. The first relates to an oscillating structure near the axis, which arises at a small value of the swirl parameter, as well as to a generation of vortices that move downstream. The second shows, for greater values of the swirl parameter, vortices interacting with the boundary layer located on the wall of the static container that is perpendicular to the flow direction. In addition, we find a transition from stable to unstable vortex breakdown when perturbations become absolutely unstable inside the rotating pipe flow. Therefore, the most remarkable experimental finding is a new state, namely, unstable or transient vortex breakdown that takes place for the same pair of values (Rea, Sa) at which the onset of the absolute instability curve appears and intersects the region of stable vortex breakdown.

  15. Income Eligibility Thresholds, Premium Contributions, and Children's Coverage Outcomes: A Study of CHIP Expansions

    PubMed Central

    Gresenz, Carole Roan; Edgington, Sarah E; Laugesen, Miriam J; Escarce, José J

    2013-01-01

    Objective To understand the effects of Children's Health Insurance Program (CHIP) income eligibility thresholds and premium contribution requirements on health insurance coverage outcomes among children. Data Sources 2002–2009 Annual Social and Economic Supplements of the Current Population Survey linked to data from multiple secondary data sources. Study Design We use a selection correction model to simultaneously estimate program eligibility and coverage outcomes conditional upon eligibility. We simulate the effects of three premium schedules representing a range of generosity levels and the effects of income eligibility thresholds ranging from 200 to 400 percent of the federal poverty line. Principal Findings Premium contribution requirements decrease enrollment in public coverage and increase enrollment in private coverage, with larger effects for greater contribution levels. Our simulation results suggest minimal changes in coverage outcomes from eligibility expansions to higher income families under premium schedules that require more than a modest contribution (medium or high schedules). Conclusions Our simulation results are useful counterpoints to previous research that has estimated the average effect of program expansions as they were implemented without disentangling the effects of premiums or other program features. The sensitivity to premiums observed suggests that although contribution requirements may be effective in reducing crowd-out, they also have the potential, depending on the level of contribution required, to nullify the effects of CHIP expansions entirely. The persistence of uninsurance among children under the range of simulated scenarios points to the importance of Affordable Care Act provisions designed to make the process of obtaining coverage transparent and navigable. PMID:23398477

  16. Human Adipose-Tissue Derived Stromal Cells in Combination with Hypoxia Effectively Support Ex Vivo Expansion of Cord Blood Haematopoietic Progenitors

    PubMed Central

    Andreeva, Elena R.; Buravkov, Sergey V.; Romanov, Yury A.; Buravkova, Ludmila B.

    2015-01-01

    The optimisation of haematopoietic stem and progenitor cell expansion is on demand in modern cell therapy. In this work, haematopoietic stem/progenitor cells (HSPCs) have been selected from unmanipulated cord blood mononuclear cells (cbMNCs) due to adhesion to human adipose-tissue derived stromal cells (ASCs) under standard (20%) and tissue-related (5%) oxygen. ASCs efficiently maintained viability and supported further HSPC expansion at 20% and 5% O2. During co-culture with ASCs, a new floating population of differently committed HSPCs (HSPCs-1) grew. This suspension was enriched with СD34+ cells up to 6 (20% O2) and 8 (5% O2) times. Functional analysis of HSPCs-1 revealed cobble-stone area forming cells (CAFCs) and lineage-restricted colony-forming cells (CFCs). The number of CFCs was 1.6 times higher at tissue-related O2, than in standard cultivation (20% O2). This increase was related to a rise in the number of multipotent precursors - BFU-E, CFU-GEMM and CFU-GM. These changes were at least partly ensured by the increased concentration of MCP-1 and IL-8 at 5% O2. In summary, our data demonstrated that human ASCs enables the selection of functionally active HSPCs from unfractionated cbMNCs, the further expansion of which without exogenous cytokines provides enrichment with CD34+ cells. ASCs efficiently support the viability and proliferation of cord blood haematopoietic progenitors of different commitment at standard and tissue-related O2 levels at the expense of direct and paracrine cell-to-cell interactions. PMID:25919031

  17. Genetic Code Expansion as a Tool to Study Regulatory Processes of Transcription

    NASA Astrophysics Data System (ADS)

    Schmidt, Moritz; Summerer, Daniel

    2014-02-01

    The expansion of the genetic code with noncanonical amino acids (ncAA) enables the chemical and biophysical properties of proteins to be tailored, inside cells, with a previously unattainable level of precision. A wide range of ncAA with functions not found in canonical amino acids have been genetically encoded in recent years and have delivered insights into biological processes that would be difficult to access with traditional approaches of molecular biology. A major field for the development and application of novel ncAA-functions has been transcription and its regulation. This is particularly attractive, since advanced DNA sequencing- and proteomics-techniques continue to deliver vast information on these processes on a global level, but complementing methodologies to study them on a detailed, molecular level and in living cells have been comparably scarce. In a growing number of studies, genetic code expansion has now been applied to precisely control the chemical properties of transcription factors, RNA polymerases and histones, and this has enabled new insights into their interactions, conformational changes, cellular localizations and the functional roles of posttranslational modifications.

  18. A study of single and binary ion plasma expansion into laboratory-generated plasma wakes

    NASA Technical Reports Server (NTRS)

    Wright, Kenneth Herbert, Jr.

    1988-01-01

    Plasma expansion into the wake of a large rectangular plate immersed in a collisionless, supersonic plasma was investigated in laboratory experiments. The experimental conditions address both single ion and binary ion plasma flows for the case of a body whose size is large in comparison with the Debye length, when the potential difference between the body and the plasma is relatively small. A new plasma source was developed to generate equi-velocity, binary ion plasma flows, which allows access to new parameter space that have previously been unavailable for laboratory studies. Specifically, the new parameters are the ionic mass ratio and the ionic component density ratio. In a series of experiments, a krypton-neon plasma is employed where the ambient density ratio of neon to krypton is varied more than an order of magnitude. The expansion in both the single ion and binary ion plasma cases is limited to early times, i.e., a few ion plasma periods, by the combination of plasma density, plasma drift speed, and vacuum chamber size, which prevented detailed comparison with self-similar theory.

  19. A Study of Free-Piston Double-Diaphragm Drivers for Expansion Tubes. Report 1

    NASA Technical Reports Server (NTRS)

    Kendall, M. A.

    1997-01-01

    In recent years the free-piston double-diaphragm driver has been used to increase the performance of the XI pilot expansion tube to super-orbital test conditions. However, the actual performance of the double-diaphragm driver was found to be considerably less than ideal. An experimental study of the double-diaphragm driver was carried out on the XI facility over a range of conditions with the objective of determining the effect of. heat losses; and the non-ideal rupture of the 'light' secondary diaphragm on the driver performance. The disparity between the theoretical and measured performance envelope are highlighted. A viscous limit for the experiments vas established. Heat transfer behind the primary shock is shown to be the mechanism behind this limit Incident, reflected and transmitted shock trajectories for the secondary diaphragm were experimentally determined and compared with computed trajectories from a one-dimensional diaphragm inertia model. It was found that the diaphragm did influence the unsteady expansion. A good agreement between experimental and computed shock trajectories was obtained using a diaphragm inertia model assuming that the diaphragm mass became negligible 3 microns after shock impact.

  20. 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

  1. Periodontal and dental effects of surgically assisted rapid maxillary expansion, assessed by using digital study models

    PubMed Central

    Siqueira, Danilo Furquim; Cardoso, Mauricio de Almeida; Capelozza, Leopoldino; Goldenberg, Dov Charles; Fernandes, Mariana dos Santos

    2015-01-01

    OBJECTIVE: The present study assessed the maxillary dental arch changes produced by surgically assisted rapid maxillary expansion (SARME). METHODS: Dental casts from 18 patients (mean age of 23.3 years) were obtained at treatment onset (T1), three months after SARME (T2) and 6 months after expansion (T3). The casts were scanned in a 3D scanner (D-250, 3Shape, Copenhagen, Denmark). Maxillary dental arch width, dental crown tipping and height were measured and assessed by ANOVA and Tukey's test. RESULTS: Increased transversal widths from T1 and T2 and the maintenance of these values from T2 and T3 were observed. Buccal teeth tipping also showed statistically significant differences, with an increase in all teeth from T1 to T2 and a decrease from T2 to T3. No statistically significant difference was found for dental crown height, except for left first and second molars, although clinically irrelevant. CONCLUSION: SARME proved to be an effective and stable procedure, with minimum periodontal hazards. PMID:26154457

  2. Phase transition and thermal expansion studies of alumina thin films prepared by reactive pulsed laser deposition.

    PubMed

    Balakrishnan, G; Thirumurugesan, R; Mohandas, E; Sastikumar, D; Kuppusami, P; Songl, J I

    2014-10-01

    Aluminium oxide (Al2O3) thin films were deposited on Si (100) substrates at an optimized oxygen partial pressure of 3 x 10(-3) mbar at room temperature by pulsed laser deposition (PLD). The films were characterized by high temperature X-ray diffraction (HTXRD), field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM). The HTXRD pattern showed the cubic y-Al2O3 phase in the temperature range 300-973 K. At temperatures ≥ 1073 K, the δ and θ-phases of Al2O3 were observed. The mean linear thermal expansion coefficient and volume thermal expansion coefficient of γ-Al2O3 was found to be 12.66 x 10(-6) K(-1) and 38.87 x 10(-6) K(-1) in the temperature range 300 K-1073 K. The field emission scanning electron microscopy revealed a smooth and structureless morphology of the films deposited on Si (100). The atomic force microscopy study indicated the increased crystallinity and surface roughness of the films after annealing at high temperature.

  3. Direct simulation Monte Carlo study of quantum effects on the spherical expansion of 4He

    NASA Astrophysics Data System (ADS)

    Koura, Katsuhisa

    1999-10-01

    Quantum effects on the translational nonequilibrium at low temperatures in a spherical expansion of 4He from room temperature are studied using the direct simulation Monte Carlo method to make a comparison with the experimental measurements along the axis of a helium free jet expansion. The quantum-mechanical scattering cross sections are obtained by a quantum phase-shift calculation for the Lennard-Jones and more elaborate Hartree-Fock dispersion potentials. It is shown that the parallel and perpendicular kinetic temperatures are higher and lower, respectively, for the quantum-mechanical scattering than for the classical-mechanical scattering. A comparison with the parallel temperature determined by fitting the ellipsoidal velocity distribution function to the measured spectral profiles indicates that the parallel kinetic temperature for the quantum-mechanical scattering is higher than the measured temperature, with which the parallel kinetic temperature for the classical-mechanical scattering is fortuitously in better agreement. Because both the parallel and perpendicular velocity distribution functions appreciably deviate from Maxwellians and the Maxwellian (half-width) fit temperatures are lower than the kinetic temperatures, the discrepancy between the quantum-mechanical and measured parallel temperatures may partly be resolved by the difference between the kinetic and fitting temperatures.

  4. Use of Microwave Technique for Study of Isentropic Detonation Products Expansion

    NASA Astrophysics Data System (ADS)

    Bogdanov, Evgeny; Belsky, Vladimir; Zhernokletov, Mikhail; Mikhaylov, Anatoly; Rodionov, Alexey; Sedov, Alexander; Russian Federal Nuclear Center-Vniief 607190, Sarov, Nizhniy Novgorod Reg., Russia Team

    2013-06-01

    Application of the microwave technique for research of explosives and their detonation products can give a number of advantages as compared to the other experimental techniques. This technique makes it possible to perform a continuous recording of the shock and detonation waves motion directly in explosive. A significant advantage of the technique consists in absence of influence on investigated process, because there are no any sensors, optic fiber etc. in an explosive volume. The microwave technique was used for isentropic detonation products expansion study of HMX/TATB-based explosive compound. For determination of states on the expansion adiabat of detonation products, the experimental series was conducted. In these experiments we recorded time dependences of the shock wave velocities in dielectric microwave-transparent barriers, which were in contact with explosive samples. A low power 94 GHz quadrature interferometer was used. The conducted experiments showed that the use of microwave technique gives a big amount of interesting experimental data with a considerable research simplification.

  5. Growth Type and Functional Trajectories: An Empirical Study of Urban Expansion in Nanjing, China.

    PubMed

    Chen, Jianglong; Gao, Jinlong; 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.

  6. A study of laser-plasma expansion into the background gas by means of high-speed photography

    NASA Astrophysics Data System (ADS)

    Anan'in, O. B.; Bykovskii, Iu. A.; Eremin, Iu. V.; Stupitskii, E. L.; Novikov, I. K.; Frolov, S. P.

    1991-07-01

    A method for studying laser-plasma behavior in a vacuum and in a background gas by means of high-speed photography is presented. Photographs of laser-plasma expansion into the background gas at different pressures are analyzed. The detection of hydrodynamic instability of the laser plasma front during expansion into the background gas is reported. A theoretical analysis of the experimental results is presented.

  7. A Robust Single Primate Neuroepithelial Cell Clonal Expansion System for Neural Tube Development and Disease Studies

    PubMed Central

    Zhu, Xiaoqing; Li, Bo; Ai, Zongyong; Xiang, Zheng; Zhang, Kunshang; Qiu, Xiaoyan; Chen, Yongchang; Li, Yuemin; Rizak, Joshua D.; Niu, Yuyu; Hu, Xintian; Sun, Yi Eve; Ji, Weizhi; Li, Tianqing

    2015-01-01

    Summary Developing a model of primate neural tube (NT) development is important to promote many NT disorder studies in model organisms. Here, we report a robust and stable system to allow for clonal expansion of single monkey neuroepithelial stem cells (NESCs) to develop into miniature NT-like structures. Single NESCs can produce functional neurons in vitro, survive, and extensively regenerate neuron axons in monkey brain. NT formation and NESC maintenance depend on high metabolism activity and Wnt signaling. NESCs are regionally restricted to a telencephalic fate. Moreover, single NESCs can turn into radial glial progenitors (RGPCs). The transition is accurately regulated by Wnt signaling through regulation of Notch signaling and adhesion molecules. Finally, using the “NESC-TO-NTs” system, we model the functions of folic acid (FA) on NT closure and demonstrate that FA can regulate multiple mechanisms to prevent NT defects. Our system is ideal for studying NT development and diseases. PMID:26584544

  8. A correlated study of laser produced plume expansion dynamics and thin film growth of manganates

    NASA Astrophysics Data System (ADS)

    Amoruso, S.; Angeloni, M.; Balestrino, G.; Boggio, N.; Bruzzese, R.; Medaglia, P. G.; Tebano, A.; Vitiello, M.; Wang, X.

    2005-07-01

    Thin films of La 0.67Ba 0.33MnO 3 were deposited on NdGaO 3 by pulsed laser deposition with in situ RHEED diagnostics. A strong dependence of structural and electrical transport properties of the films on the background oxygen pressure was observed. Electrical resistance versus temperature and X-ray diffraction measurements were used to characterise the deposited films. Deposition at low background oxygen pressure (≈10 -1 Pa) resulted in a good structural quality with an atomically flat surface, but poorer transport properties compared to films grown at higher pressure (≈50 Pa). These observations have been correlated with the characteristics of the plume expansion by studying pulsed laser ablation of manganate samples into oxygen background gas by optical emission spectroscopy and ion probe diagnostics. These studies have been carried out using the parent LaMnO 3 compound as target material in presence of an oxidizing atmosphere.

  9. Thermal expansion coefficient of graphene using molecular dynamics simulation: A comparative study on potential functions

    NASA Astrophysics Data System (ADS)

    Ghasemi, Hamid; Rajabpour, Ali

    2017-01-01

    In this paper, we studied the thermal expansion coefficient (TEC) of pristine graphene sheets (GSs) using molecular dynamics (MD) simulation. We validated our model with previous studies employing AIREBO potential function and repeated the same simulation with the optimized Tersoff potential function. We also discussed the differences of the results and the corresponding reasons: evaluating the negative TEC of graphene by measuring the C-C bond length and out-of-plane vibrations of the GS. We finally showed that the ripples and wrinkles are more represented over the GS during the simulation with the AIREBO potential function rather than the optimized Tersoff. Comparing the results of both potential functions; it is seen that the results obtained by AIREBO potential function are in better agreement with those reported by previous scholars.

  10. Early osteoinductive human bone marrow mesenchymal stromal/stem cells support an enhanced hematopoietic cell expansion with altered chemotaxis- and adhesion-related gene expression profiles.

    PubMed

    Sugino, Noriko; Miura, Yasuo; Yao, Hisayuki; Iwasa, Masaki; Fujishiro, Aya; Fujii, Sumie; Hirai, Hideyo; Takaori-Kondo, Akifumi; Ichinohe, Tatsuo; Maekawa, Taira

    2016-01-22

    Bone marrow (BM) microenvironment has a crucial role in supporting hematopoiesis. Here, by using a microarray analysis, we demonstrate that human BM mesenchymal stromal/stem cells (MSCs) in an early osteoinductive stage (e-MSCs) are characterized by unique hematopoiesis-associated gene expression with an enhanced hematopoiesis-supportive ability. In comparison to BM-MSCs without osteoinductive treatment, gene expression in e-MSCs was significantly altered in terms of their cell adhesion- and chemotaxis-related profiles, as identified with Gene Ontology and Gene Set Enrichment Analysis. Noteworthy, expression of the hematopoiesis-associated molecules CXCL12 and vascular cell adhesion molecule 1 was remarkably decreased in e-MSCs. e-MSCs supported an enhanced expansion of CD34(+) hematopoietic stem and progenitor cells, and generation of myeloid lineage cells in vitro. In addition, short-term osteoinductive treatment favored in vivo hematopoietic recovery in lethally irradiated mice that underwent BM transplantation. e-MSCs exhibited the absence of decreased stemness-associated gene expression, increased osteogenesis-associated gene expression, and apparent mineralization, thus maintaining the ability to differentiate into adipogenic cells. Our findings demonstrate the unique biological characteristics of e-MSCs as hematopoiesis-regulatory stromal cells at differentiation stage between MSCs and osteoprogenitor cells and have significant implications in developing new strategy for using pharmacological osteoinductive treatment to support hematopoiesis in hematopoietic stem and progenitor cell transplantation. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. An analysis of combustion studies in shock expansion tunnels and reflected shock tunnels

    NASA Technical Reports Server (NTRS)

    Jachimowski, Casimir J.

    1992-01-01

    The effect of initial nonequilibrium dissociated air constituents on the combustion of hydrogen in high-speed flows for a simulated Mach 17 flight condition was investigated by analyzing the results of comparative combustion experiments performed in a reflected shock tunnel test gas and in a shock expansion tunnel test gas. The results were analyzed and interpreted with a one-dimensional quasi-three-stream combustor code that includes finite rate combustion chemistry. The results of this study indicate that the combustion process is kinetically controlled in the experiments in both tunnels and the presence of the nonequilibrium partially dissociated oxygen in the reflected shock tunnel enhances the combustion. Methods of compensating for the effect of dissociated oxygen are discussed.

  12. Mesenchymal Stem Cells Secreting Angiopoietin-Like-5 Support Efficient Expansion of Human Hematopoietic Stem Cells Without Compromising Their Repopulating Potential

    PubMed Central

    Khoury, Maroun; Drake, Adam; Chen, Qingfeng; Dong, Di; Leskov, Ilya; Fragoso, Maria F.; Li, Yan; Iliopoulou, Bettina P.; Hwang, William; Lodish, Harvey F.

    2011-01-01

    Clinical and preclinical applications of human hematopoietic stem cells (HSCs) are often limited by scarcity of cells. Expanding human HSCs to increase their numbers while maintaining their stem cell properties has therefore become an important area of research. Here, we report a robust HSC coculture system wherein cord blood CD34+ CD133+ cells were cocultured with mesenchymal stem cells engineered to express angiopoietin-like-5 in a defined medium. After 11 days of culture, SCID repopulating cells were expanded ∼60-fold by limiting dilution assay in NOD-scid Il2rg−/− (NSG) mice. The cultured CD34+ CD133+ cells had similar engraftment potential to uncultured CD34+ CD133+ cells in competitive repopulation assays and were capable of efficient secondary reconstitution. Further, the expanded cells supported a robust multilineage reconstitution of human blood cells in NSG recipient mice, including a more efficient T-cell reconstitution. These results demonstrate that the expanded CD34+ CD133+ cells maintain both short-term and long-term HSC activities. To our knowledge, this ∼60-fold expansion of SCID repopulating cells is the best expansion of human HSCs reported to date. Further development of this coculture method for expanding human HSCs for clinical and preclinical applications is therefore warranted. PMID:21142526

  13. Study on a new type of jet pressurization evaporation expansion apparatus

    NASA Astrophysics Data System (ADS)

    Chen, Boyi; Zhang, Mingxin; Yang, Li

    2001-04-01

    The volume expansion of the stuff (e. g. tobacco stem) is of great importance to an increase in the product quality and a decrease in the production cost. This paper puts forward the basic configuration and the expansion mechanism of a new type of jet pressurization evaporation expansion apparatus. By the thermodynamic calculation of the apparatus, we give variations in steam pressure on various cross sections of the flow system for the apparatus, manufacture a sample machine, and finish run tests of the machine. The test results show that the apparatus may make the relative increase in fill value of tobacco stem higher than 75%, and may cause the steam consumption required in the expansion process of each kilogram stem to reduced about 40% compared with conventional expansion apparatus. Additionally, the configuration of the apparatus is simple and small, its cost of manufacture is very low, and both its operation and maintenance are extremely convenient.

  14. Ab initio study of the phononic origin of negative thermal expansion

    NASA Astrophysics Data System (ADS)

    Argaman, Uri; Eidelstein, Eitan; Levy, Ohad; Makov, Guy

    2016-11-01

    Negative thermal expansion is an uncommon phenomenon of theoretical interest. Multiple hypotheses regarding its microscopic origins have been suggested. In this paper, the thermal expansion of a representative semiconductor, Si, and a representative metal, Ti, are calculated ab initio using density-functional perturbation theory. The phonon modes' contributions to the thermal expansion are analyzed and the negative thermal expansion is shown to be dominated by negative mode Grüneisen parameters at specific points on the Brillouin zone boundaries. Thus, the elastic (Debye) theory for negative thermal expansion is shown to be irrelevant for these phenomena. The anomalous behavior of these modes in Ti is shown to be unaffected by an electronic topological transition as previously suggested, instead it arises from complex interplay of atomic displacements of the anomalous mode.

  15. Applications of Floquet-Magnus expansion, average Hamiltonian theory and Fer expansion to study interactions in solid state NMR when irradiated with the magic-echo sequence.

    PubMed

    Mananga, Eugene Stephane

    2013-01-01

    This work presents the possibility of applying the Floquet-Magnus expansion and the Fer expansion approaches to the most useful interactions known in solid-state nuclear magnetic resonance using the magic-echo scheme. The results of the effective Hamiltonians of these theories and average Hamiltonian theory are presented. © 2013 Elsevier Inc. All rights reserved.

  16. Applications of Floquet-Magnus expansion, average Hamiltonian theory and Fer expansion to study interactions in solid state NMR when irradiated with the magic-echo sequence

    PubMed Central

    Mananga, Eugene Stephane

    2015-01-01

    This work presents the possibility of applying the Floquet-Magnus expansion and the Fer expansion approaches to the most useful interactions known in solid-state nuclear magnetic resonance using the magic-echo scheme. The results of the effective Hamiltonians of these theories and average Hamiltonian theory are presented. PMID:24034855

  17. A simulation study of radial expansion of an electron beam injected into an ionospheric plasma

    NASA Technical Reports Server (NTRS)

    Koga, J.; Lin, C. S.

    1994-01-01

    Injections of nonrelativistic electron beams from a finite equipotential conductor into an ionospheric plasma have been simulated using a two-dimensional electrostatic particle code. The purpose of the study is to survey the simulation parameters for understanding the dependence of beam radius on physical variables. The conductor is charged to a high potential when the background plasma density is less than the beam density. Beam electrons attracted by the charged conductor are decelerated to zero velocity near the stagnation point, which is at a few Debye lengths from the conductor. The simulations suggest that the beam electrons at the stagnation point receive a large transverse kick and the beam expands radially thereafter. The buildup of beam electrons at the stagnation point produces a large electrostatic force responsible for the transverse kick. However, for the weak charging cases where the background plasma density is larger than the beam density, the radial expansion mechanism is different; the beam plasma instability is found to be responsible for the radial expansion. The simulations show that the electron beam radius for high spacecraft charging cases is of the order of the beam gyroradius, defined as the beam velocity divided by the gyrofrequency. In the weak charging cases, the beam radius is only a fraction of the beam gyroradius. The parameter survey indicates that the beam radius increases with beam density and decreases with magnetic field and beam velocity. The beam radius normalized by the beam gyroradius is found to scale according to the ratio of the beam electron Debye length to the ambient electron Debye length. The parameter dependence deduced would be useful for interpreting the beam radius and beam density of electron beam injection experiments conducted from rockets and the space shuttle.

  18. Universal Expansion.

    ERIC Educational Resources Information Center

    McArdle, Heather K.

    1997-01-01

    Describes a week-long activity for general to honors-level students that addresses Hubble's law and the universal expansion theory. Uses a discrepant event-type activity to lead up to the abstract principles of the universal expansion theory. (JRH)

  19. Universal Expansion.

    ERIC Educational Resources Information Center

    McArdle, Heather K.

    1997-01-01

    Describes a week-long activity for general to honors-level students that addresses Hubble's law and the universal expansion theory. Uses a discrepant event-type activity to lead up to the abstract principles of the universal expansion theory. (JRH)

  20. New Mitochondrial and Nuclear Evidences Support Recent Demographic Expansion and an Atypical Phylogeographic Pattern in the Spittlebug Philaenus spumarius (Hemiptera, Aphrophoridae)

    PubMed Central

    Rodrigues, Ana S. B.; Silva, Sara E.; Marabuto, Eduardo; Silva, Diogo N.; Wilson, Mike R.; Thompson, Vinton; Yurtsever, Selçuk; Halkka, Antti; Borges, Paulo A. V.; Quartau, José A.; Paulo, Octávio S.; Seabra, Sofia G.

    2014-01-01

    Philaenus spumarius is a widespread insect species in the Holarctic region. Here, by focusing on the mtDNA gene COI but also using the COII and Cyt b genes and the nuclear gene EF-1α, we tried to explain how and when its current biogeographic pattern evolved by providing time estimates of the main demographic and evolutionary events and investigating its colonization patterns in and out of Eurasia. Evidence of recent divergence and expansion events at less than 0.5 Ma ago indicate that climate fluctuations in the Mid-Late Pleistocene were important in shaping the current phylogeographic pattern of the species. Data support a first split and differentiation of P. spumarius into two main mitochondrial lineages: the “western”, in the Mediterranean region and the “eastern”, in Anatolia/Caucasus. It also supports a following differentiation of the “western” lineage into two sub-lineages: the “western-Mediterranean”, in Iberia and the “eastern-Mediterranean” in the Balkans. The recent pattern seems to result from postglacial range expansion from Iberia and Caucasus/Anatolia, thus not following one of the four common paradigms. Unexpected patterns of recent gene-flow events between Mediterranean peninsulas, a close relationship between Iberia and North Africa, as well as high levels of genetic diversity being maintained in northern Europe were found. The mitochondrial pattern does not exactly match to the nuclear pattern suggesting that the current biogeographic pattern of P. spumarius may be the result of both secondary admixture and incomplete lineage sorting. The hypothesis of recent colonization of North America from both western and northern Europe is corroborated by our data and probably resulted from accidental human translocations. A probable British origin for the populations of the Azores and New Zealand was revealed, however, for the Azores the distribution of populations in high altitude native forests is somewhat puzzling and may imply a

  1. Early osteoinductive human bone marrow mesenchymal stromal/stem cells support an enhanced hematopoietic cell expansion with altered chemotaxis- and adhesion-related gene expression profiles

    SciTech Connect

    Sugino, Noriko; Miura, Yasuo; Yao, Hisayuki; Iwasa, Masaki; Fujishiro, Aya; Fujii, Sumie; Hirai, Hideyo; Takaori-Kondo, Akifumi; Maekawa, Taira

    2016-01-22

    Bone marrow (BM) microenvironment has a crucial role in supporting hematopoiesis. Here, by using a microarray analysis, we demonstrate that human BM mesenchymal stromal/stem cells (MSCs) in an early osteoinductive stage (e-MSCs) are characterized by unique hematopoiesis-associated gene expression with an enhanced hematopoiesis-supportive ability. In comparison to BM-MSCs without osteoinductive treatment, gene expression in e-MSCs was significantly altered in terms of their cell adhesion- and chemotaxis-related profiles, as identified with Gene Ontology and Gene Set Enrichment Analysis. Noteworthy, expression of the hematopoiesis-associated molecules CXCL12 and vascular cell adhesion molecule 1 was remarkably decreased in e-MSCs. e-MSCs supported an enhanced expansion of CD34{sup +} hematopoietic stem and progenitor cells, and generation of myeloid lineage cells in vitro. In addition, short-term osteoinductive treatment favored in vivo hematopoietic recovery in lethally irradiated mice that underwent BM transplantation. e-MSCs exhibited the absence of decreased stemness-associated gene expression, increased osteogenesis-associated gene expression, and apparent mineralization, thus maintaining the ability to differentiate into adipogenic cells. Our findings demonstrate the unique biological characteristics of e-MSCs as hematopoiesis-regulatory stromal cells at differentiation stage between MSCs and osteoprogenitor cells and have significant implications in developing new strategy for using pharmacological osteoinductive treatment to support hematopoiesis in hematopoietic stem and progenitor cell transplantation. - Highlights: • Human BM-MSCs in an early osteoinductive stage (e-MSCs) support hematopoiesis. • Adhesion- and chemotaxis-associated gene signatures are altered in e-MSCs. • Expression of CXCL12 and VCAM1 is remarkably decreased in e-MSCs. • e-MSCs are at differentiation stage between MSCs and osteoprogenitor cells. • Osteoinductive treatment

  2. Computational study of single-expansion-ramp nozzles with external burning

    NASA Technical Reports Server (NTRS)

    Yungster, Shaye; Trefny, Charles J.

    1992-01-01

    A computational investigation of the effects of external burning on the performance of single expansion ramp nozzles (SERN) operating at transonic speeds is presented. The study focuses on the effects of external heat addition and introduces a simplified injection and mixing model based on a control volume analysis. This simplified model permits parametric and scaling studies that would have been impossible to conduct with a detailed CFD analysis. The CFD model is validated by comparing the computed pressure distribution and thrust forces, for several nozzle configurations, with experimental data. Specific impulse calculations are also presented which indicate that external burning performance can be superior to other methods of thrust augmentation at transonic speeds. The effects of injection fuel pressure and nozzle pressure ratio on the performance of SERN nozzles with external burning are described. The results show trends similar to those reported in the experimental study, and provide additional information that complements the experimental data, improving our understanding of external burning flowfields. A study of the effect of scale is also presented. The results indicate that combustion kinetics do not make the flowfield sensitive to scale.

  3. Application of the stellarator expansion for plasma-stability studies in stellarators

    SciTech Connect

    Anania, G.; Johnson, J.L.

    1983-04-01

    A numerical code, which utilizes the stellarator expansion, is developed and tested. It is used to investigate the magnetohydrodynamic stability properties of several stellarator configurations, including Heliotron E, Wendelstein VII-A, a modular-coil device, and ATF-1.

  4. Ultraprecise studies of the thermal expansion coefficient of diamond using backscattering x-ray diffraction.

    SciTech Connect

    Stoupin, S.; Shvyd'ko, Y.

    2011-03-17

    The linear thermal expansion coefficient of diamond crystals of type IIa and type Ia was measured in the temperature range from 10 to 295 K. Neither negative thermal expansion nor any substantial difference in the thermal expansion coefficient in crystals of the different types were observed. An empirical expression was obtained that approximates the temperature dependence of the thermal expansion coefficient of diamond. The T{sup 3} temperature dependence of a Debye solid holds below {approx}100 K with an accuracy of {approx}10{sup -8} K{sup -1}. A slight increase in the value of the lattice parameter was found for the Ia-type crystal, which suggests lattice dilatation by nitrogen impurity. The measurements were performed using Bragg diffraction in backscattering from diamond crystals of highly monochromatic 23.7 keV x rays with the recently demonstrated high relative accuracy of 1.2 x 10{sup -8} in the determination of the lattice parameter.

  5. Negative thermal expansion in CuCl: An extended x-ray absorption fine structure study

    SciTech Connect

    Vaccari, M.; Grisenti, R.; Fornasini, P.; Rocca, F.; Sanson, A.

    2007-05-01

    Extended x-ray absorption fine structure (EXAFS) has been measured from liquid helium to ambient temperature at the Cu K edge of copper chloride (CuCl) to investigate the local origin of negative thermal expansion. A quantitative analysis of the first coordination shell, performed by the cumulant method, reveals that the nearest-neighbor Cu-Cl interatomic distance undergoes a strong positive expansion, contrasting with the much weaker negative expansion of the crystallographic distance between average atomic positions below 100 K. The anisotropy of relative thermal vibrations, monitored by the ratio {gamma} between perpendicular and parallel mean square relative displacements, is considerably high, while the diffraction thermal factors are isotropic. The relative perpendicular vibrations measured by EXAFS are related to the tension mechanism and to the transverse acoustic modes, which are considered responsible for negative thermal expansion in zinc-blende structures.

  6. Clinical Studies of Ex Vivo Expansion to Accelerate Engraftment After Umbilical Cord Blood Transplantation: A Systematic Review.

    PubMed

    Kiernan, Jeffrey; Damien, Pauline; Monaghan, Madeline; Shorr, Risa; McIntyre, Lauralyn; Fergusson, Dean; Tinmouth, Alan; Allan, David

    2016-12-23

    Cell dose limits greater use of umbilical cord blood (UCB) in hematopoietic cell transplantation. The clinical benefits of ex vivo expansion need clarity to understand its potential impact. A systematic search of studies addressing UCB ex vivo expansion was conducted. Fifteen clinical studies (349 transplanted patients) and 13 registered trials were identified. The co-infusion of an expanded unit and a second unmanipulated unit (8 studies), the fractional expansion of 12% to 60% of a single unit (5 studies), and the infusion of a single expanded unit (2 studies) were reported. More recently, published studies and 12 of 13 ongoing trials involve the use of novel small molecules in addition to traditional cytokine cocktails. Higher total cell number was closely associated with faster neutrophil engraftment. Compared with historical controls, neutrophil engraftment was significantly accelerated in more recent studies using small molecules or mesenchymal stromal cells (MSC) co-culture, and in some cases, platelet recovery was also statistically improved. Recent studies using nicotinamide and StemRegenin-1 reported long-term chimerism of the expanded unit. No significant improvement in survival or other transplant-related outcomes was demonstrated for any of the strategies. Ex vivo expansion of UCB can accelerate initial neutrophil engraftment after transplant. More recent studies suggest that long-term engraftment of ex vivo expanded cord blood units is achievable. Results of larger randomized controlled trials are needed to understand the impact on patient outcomes and health care costs.

  7. Sugarcane Water Sustainability Assessment Through the Indicators Extracted from Spatial Models: Case Study of Sugarcane Expansion Hotspots in Brazil

    NASA Astrophysics Data System (ADS)

    Ferraz, R. P.; Simoes, M.; Dubreuil, V.

    2012-12-01

    The CanaSat project data from INPE (2010) has evidenced the trend of sugarcane expansion into savanna areas in the Midwest region of Brazil that has a great potential for the sugarcane development, in terms of topography and suitable soils, according to Sugarcane Agroecological Zoning (EMBRAPA, 2009). However, in this region the climatic water availability has limitations, once the climate is marked by drought season with a strong water deficiency due to reduction of rainfall (SILVA et al. 2008). There may be serious risks to the sugarcane culture conducted in dryland crop system without any support from additional irrigation. Silva et al. (2008) state that, for the expansion of sugarcane cultivation in the Cerrado region will be necessary supplemental irrigation with 80 to 120 mm of water applied after cutting or planting. In the Brazilian Midwest the sugarcane agroindustry expansion is technically viable, but for the sustainable development of this activity it is necessary an adequate planning based on knowledge about water demand and availability. The aim of this study was to conduct an assessment of the potential water sustainability for the sugarcane cultivation in four microregions in Goiás State, Brazil, through the use of indicators proposed in Indicators System of Sugarcane Water Sustainability Assessment (Ferraz, 2012), that was thought to subsidize the public policies proposals and sectoral planning in strategic level by means of indicators that enable to perform diagnostic and prognostic analysis. These indicators are direct and relevant indexes obtained from data extracted through geoprocessing techniques from integration of many spatial models. The used indicators were: (i) Three indexes expressing the land favorability for sugarcane development conducted in dryland or irrigation system through the establishment of the ratio between the sugarcane suitable area for each different system and the total area of territorial unit of analysis (micro

  8. Effect of surgically assisted rapid maxillary expansion on masticatory muscle activity: A pilot study

    PubMed Central

    Sverzut, Cássio E.; Martorelli, Karinna; Jabur, Roberto; Petri, Alice D.; Trivellato, Alexandre E.; Siéssere, Selma; Regalo, Simone C. H.

    2011-01-01

    Background: The aim of the present study was to analyze the electromyographic (EMG) activity of masseter and temporal muscles of adult patients submitted to surgically assisted rapid maxillary expansion (SARME) before and after the surgery. Materials and Methods: The sample consisted of 19 adults, with ages ranging from 20 to 47 years (mean 25.4 years), with bilateral posterior cross bite requiring SARME treatment. The electromyographic activity of masseter and temporal muscles was analyzed before treatment (T1) and after the surgical procedure (T2). The mean interval between the two electromyographic analyses was 15 days. Results: The muscular active was electromyographically analyzed during the clinical situation of habitual gum chewing (10 sec), dental clenching (4 sec), mouth opening and closing (10 sec), rest (10 sec), protrusion (10 sec), and right and left laterality (10 sec). The measured differences between T1 and T2 data were evaluated using the paired t-test (SPSS 17.0 for Windows). The electromyographic analysis showed that the activity of the masseter and temporal muscles decreased significantly after the SARME in all the clinical situations after the surgery. Conclusion: According to the results of the present study, individuals after SARME surgery presented patterns of electromyographic contraction similar to those developed by dentate individuals during the movements of mandibular excursion. PMID:23482404

  9. Dental arch changes associated with rapid maxillary expansion: A retrospective model analysis study

    PubMed Central

    D’Souza, Ivor M; Kumar, H. C. Kiran; Shetty, K. Sadashiva

    2015-01-01

    Introduction: Transverse deficiency of the maxilla is a common clinical problem in orthodontics and dentofacial orthopedics. Transverse maxillary deficiency, isolated or associated with other dentofacial deformities, results in esthetic and functional impairment giving rise to several clinical manifestations such as asymmetrical facial growth, positional and functional mandibular deviations, altered dentofacial esthetics, adverse periodontal responses, unstable dental tipping, and other functional problems. Orthopedic maxillary expansion is the preferred treatment approach to increase the maxillary transverse dimension in young patients by splitting of the mid palatal suture. This orthopedic procedure has lately been subject of renewed interest in orthodontic treatment mechanics because of its potential for increasing arch perimeter to alleviate crowding in the maxillary arch without adversely affecting facial profile. Hence, the present investigation was conducted to establish a correlation between transverse expansion and changes in the arch perimeter, arch width and arch length. Methods: For this purpose, 10 subjects (five males, five females) were selected who had been treated by rapid maxillary expansion (RME) using hyrax rapid palatal expander followed by fixed mechanotherapy (PEA). Pretreatment (T1), postexpansion (T2), and posttreatment (T3) dental models were compared for dental changes brought about by RME treatment and its stability at the end of fixed mechanotherapy. After model measurements were made, the changes between T1–T2, T2–T3 and T1–T3 were determined for each patient. The mean difference between T1–T2, T2–T3 and T1–T3 were compared to assess the effects of RME on dental arch measurements. Results are expressed as mean ± standard deviation and are compared by repeated measures analysis of variance followed by a post-hoc test. Arch perimeter changes are correlated with changes in arch widths at the canine, premolar and molar regions

  10. Army technology development. IBIS query. Software to support the Image Based Information System (IBIS) expansion for mapping, charting and geodesy

    NASA Technical Reports Server (NTRS)

    Friedman, S. Z.; Walker, R. E.; Aitken, R. B.

    1986-01-01

    The Image Based Information System (IBIS) has been under development at the Jet Propulsion Laboratory (JPL) since 1975. It is a collection of more than 90 programs that enable processing of image, graphical, tabular data for spatial analysis. IBIS can be utilized to create comprehensive geographic data bases. From these data, an analyst can study various attributes describing characteristics of a given study area. Even complex combinations of disparate data types can be synthesized to obtain a new perspective on spatial phenomena. In 1984, new query software was developed enabling direct Boolean queries of IBIS data bases through the submission of easily understood expressions. An improved syntax methodology, a data dictionary, and display software simplified the analysts' tasks associated with building, executing, and subsequently displaying the results of a query. The primary purpose of this report is to describe the features and capabilities of the new query software. A secondary purpose of this report is to compare this new query software to the query software developed previously (Friedman, 1982). With respect to this topic, the relative merits and drawbacks of both approaches are covered.

  11. Army technology development. IBIS query. Software to support the Image Based Information System (IBIS) expansion for mapping, charting and geodesy

    NASA Technical Reports Server (NTRS)

    Friedman, S. Z.; Walker, R. E.; Aitken, R. B.

    1986-01-01

    The Image Based Information System (IBIS) has been under development at the Jet Propulsion Laboratory (JPL) since 1975. It is a collection of more than 90 programs that enable processing of image, graphical, tabular data for spatial analysis. IBIS can be utilized to create comprehensive geographic data bases. From these data, an analyst can study various attributes describing characteristics of a given study area. Even complex combinations of disparate data types can be synthesized to obtain a new perspective on spatial phenomena. In 1984, new query software was developed enabling direct Boolean queries of IBIS data bases through the submission of easily understood expressions. An improved syntax methodology, a data dictionary, and display software simplified the analysts' tasks associated with building, executing, and subsequently displaying the results of a query. The primary purpose of this report is to describe the features and capabilities of the new query software. A secondary purpose of this report is to compare this new query software to the query software developed previously (Friedman, 1982). With respect to this topic, the relative merits and drawbacks of both approaches are covered.

  12. Personality traits in Huntington's disease: An exploratory study of gene expansion carriers and non-carriers.

    PubMed

    Larsen, Ida Unmack; Mortensen, Erik Lykke; Vinther-Jensen, Tua; Nielsen, Jørgen Erik; Knudsen, Gitte Moos; Vogel, Asmus

    2016-12-01

    Huntington's disease (HD) is associated with risk for developing psychiatric symptoms. Vulnerability or resilience to psychiatric symptoms may be associated with personality traits. This exploratory study, aimed to investigate personality traits in a large cohort of HD carriers and at risk gene-expansion negative individuals (HD non-carriers), exploring whether carrying the HD gene or growing up in an HD family influences personality traits. Forty-seven HD carriers, Thirty-nine HD non-carriers, and 121 healthy controls answered the Danish version of the revised NEO personality inventory. Comparisons between HD carriers and HD non-carriers were mostly non-significant but the combined group of HD carriers and non-carriers showed significantly higher scores on the facets: "hostility," "assertiveness," and "activity" and on the trait "Conscientiousness" relative to controls, "Conscientiousness" have been associated with resilience to psychiatric symptoms. Twelve HD carriers and non-carriers were classified as depressed and showed significantly lower scores on "Extraversion" and "Conscientiousness" and significantly higher scores on "Neuroticism," which are associated with vulnerability to psychiatric symptoms. Our findings suggest that, there is no direct effect of the HD gene on personality traits, but that personality assessment may be relevant to use when identifying individuals from HD families who are vulnerable to develop psychiatric symptoms. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  13. Theoretical Studies of Interactions Between TATB Molecules and the Origins of Anisotropic Thermal Expansion and Growth

    SciTech Connect

    Gee, R H; Roszak, S M; Fried, L E

    2002-03-28

    TATB containing explosives tend to permanently expand as their temperatures are increased or thermally cycled, a phenomenon known as ''ratchet-growth.'' Several mechanisms as to the cause of the non-reversible growth have been proposed, and are taken up here using various different modeling techniques. High-level quantum chemistry calculations have been used in parameterization of a classical potential function suitable for atomistic simulations of TATB. The quantum-chemistry-based force field for TATB was validated by comparing condensed phase properties obtained from molecular dynamics simulations with available experimental data. No permanent growth was manifest at the molecular level. Dissipative particle dynamics simulations were carried out in order to study the geometric packing effects on the mesoscopic scale, similar to the scales representative of Ultrafine. No permanent growth was identified when only simple packing effects were considered in the TATB model. However, non-reversible growth was displayed when crystal fracture capabilities were incorporated in the model, suggesting that crystal fracture induced by the anisotropic volume expansion of TATB is the root cause for the permanent growth seen in TATB containing explosives.

  14. Subnanometer poly-silicon gap structure formation: Comparison study between size expansion and size reduction

    NASA Astrophysics Data System (ADS)

    Hashim, U.; Nazwa, T.; Dhahi, Th. S.

    2012-06-01

    This study describes the comparison among the three fabrication methods of an array of poly-silicon nanogap structures. The three different methods are size expansion technique (SET), size reduction technique (SRT) and e-beam lithography (EBL) technique. Generally, SRT involves the breaking of the primarily pattern with no gap structure into nanogap scale. Conversely, SET engages in the process of enhancing the initially microgap pattern into nanogap scale. EBL refers to a lithographic process that uses a focused beam of electrons to form the circuit patterns needed for material deposition on or removal from the wafer. Using conventional photolithography, a procedure to fabricate poly-silicon nanogap structure on the wafer scale is designed. The nanogap (NG) fabrication procedure is based on the standard CMOS technology follows by employing both methods respectively. The lateral nanogap is introduced in the fabrication process using poly-silicon as an anode electrode. The similarity and distinction will be highlighted for each particular process involved in the fabrication of nanogap structures. The simple least-cost method does not require complicated nanolithography method of fabrication but it is still possible to measure the electrical properties of a single molecule. On top of that, these techniques can be applied extensively to different designs of nanogap structure down to several nanometer levels of dimensions. The innovative method reported here can easily produce a nanogap electrode in a reproducible manner.

  15. Impacts of impervious surface expansion on soil organic carbon – a spatially explicit study

    PubMed Central

    Yan, Yan; Kuang, Wenhui; Zhang, Chi; Chen, Chunbo

    2015-01-01

    The rapid expansion of impervious surface areas (ISA) threatens soil organic carbon (SOC) pools in urbanized areas globally. The paucity of field observations on SOC under ISA (SOCISA), especially in dryland areas has limited our ability to assess the ecological impacts of ISA expansion. Based on systematically measured SOCISA (0–80 cm depth) of a dryland city, and land-use and land-cover change data derived from remotely sensed data, we investigated the magnitude and vertical/horizontal patterns of SOCISA and mapped the impact of ISA expansion on SOC storage. The mean SOCISA in the city was 5.36 ± 0.51 kg C m−2, lower than that observed in humid cities but much higher than that assumed in many regional carbon assessments. SOCISA decreased linearly as the soil depth or the horizontal distance from the open area increased. SOCISA accounted for over half of the city’s SOC stock, which decreased by 16% (primarily in the converted croplands) because of ISA expansion from 1990 to 2010. The impacts of the ISA expansion varied spatially, depending on the land- use and converted land-cover type. PMID:26642831

  16. Inclusion of College Community in the Self: A Longitudinal Study of the Role of Self-Expansion in Students' Satisfaction

    ERIC Educational Resources Information Center

    Branand, Brittany; Mashek, Debra; Wray-Lake, Laura; Coffey, John K.

    2015-01-01

    Consistent with predictions derived from the self-expansion model, this 3-year longitudinal study found that participation in more college groups during sophomore year predicted increases in inclusion of the college community in the self at the end of junior year, which further predicted increases in satisfaction with the college experience at the…

  17. 75 FR 16149 - Notice Of Amendment-OS ARRA Expansion of Research Capabilities To Study CE Complex Patients (R24...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-31

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HEALTH AND HUMAN SERVICES Agency for Healthcare Research and Quality Notice Of Amendment--OS ARRA Expansion of Research Capabilities To Study CE Complex Patients (R24) SEP Meeting With this correction notice,...

  18. Studies of beam expansion and distributed Bragg reflector lasers for fiber optics and optical signal processing. Interim report

    SciTech Connect

    Garmire, E.M.

    1981-03-03

    Separate studies were performed on beam expansion and on Distributed Bragg Reflector (DBR) lasers preliminary to monolithic integration on GaAs substrates. These components are proposed for use in optical signal processing, for fiber optic sources and for high-brightness lasers.

  19. Study of Query Expansion Techniques and Their Application in the Biomedical Information Retrieval

    PubMed Central

    Rivas, A. R.; Iglesias, E. L.; Borrajo, L.

    2014-01-01

    Information Retrieval focuses on finding documents whose content matches with a user query from a large document collection. As formulating well-designed queries is difficult for most users, it is necessary to use query expansion to retrieve relevant information. Query expansion techniques are widely applied for improving the efficiency of the textual information retrieval systems. These techniques help to overcome vocabulary mismatch issues by expanding the original query with additional relevant terms and reweighting the terms in the expanded query. In this paper, different text preprocessing and query expansion approaches are combined to improve the documents initially retrieved by a query in a scientific documental database. A corpus belonging to MEDLINE, called Cystic Fibrosis, is used as a knowledge source. Experimental results show that the proposed combinations of techniques greatly enhance the efficiency obtained by traditional queries. PMID:24723793

  20. Study of query expansion techniques and their application in the biomedical information retrieval.

    PubMed

    Rivas, A R; Iglesias, E L; Borrajo, L

    2014-01-01

    Information Retrieval focuses on finding documents whose content matches with a user query from a large document collection. As formulating well-designed queries is difficult for most users, it is necessary to use query expansion to retrieve relevant information. Query expansion techniques are widely applied for improving the efficiency of the textual information retrieval systems. These techniques help to overcome vocabulary mismatch issues by expanding the original query with additional relevant terms and reweighting the terms in the expanded query. In this paper, different text preprocessing and query expansion approaches are combined to improve the documents initially retrieved by a query in a scientific documental database. A corpus belonging to MEDLINE, called Cystic Fibrosis, is used as a knowledge source. Experimental results show that the proposed combinations of techniques greatly enhance the efficiency obtained by traditional queries.

  1. Assured Mission Support Space Architecture (AMSSA) study

    NASA Technical Reports Server (NTRS)

    Hamon, Rob

    1993-01-01

    The assured mission support space architecture (AMSSA) study was conducted with the overall goal of developing a long-term requirements-driven integrated space architecture to provide responsive and sustained space support to the combatant commands. Although derivation of an architecture was the focus of the study, there are three significant products from the effort. The first is a philosophy that defines the necessary attributes for the development and operation of space systems to ensure an integrated, interoperable architecture that, by design, provides a high degree of combat utility. The second is the architecture itself; based on an interoperable system-of-systems strategy, it reflects a long-range goal for space that will evolve as user requirements adapt to a changing world environment. The third product is the framework of a process that, when fully developed, will provide essential information to key decision makers for space systems acquisition in order to achieve the AMSSA goal. It is a categorical imperative that military space planners develop space systems that will act as true force multipliers. AMSSA provides the philosophy, process, and architecture that, when integrated with the DOD requirements and acquisition procedures, can yield an assured mission support capability from space to the combatant commanders. An important feature of the AMSSA initiative is the participation by every organization that has a role or interest in space systems development and operation. With continued community involvement, the concept of the AMSSA will become a reality. In summary, AMSSA offers a better way to think about space (philosophy) that can lead to the effective utilization of limited resources (process) with an infrastructure designed to meet the future space needs (architecture) of our combat forces.

  2. Assured Mission Support Space Architecture (AMSSA) study

    NASA Technical Reports Server (NTRS)

    Hamon, Rob

    1993-01-01

    The assured mission support space architecture (AMSSA) study was conducted with the overall goal of developing a long-term requirements-driven integrated space architecture to provide responsive and sustained space support to the combatant commands. Although derivation of an architecture was the focus of the study, there are three significant products from the effort. The first is a philosophy that defines the necessary attributes for the development and operation of space systems to ensure an integrated, interoperable architecture that, by design, provides a high degree of combat utility. The second is the architecture itself; based on an interoperable system-of-systems strategy, it reflects a long-range goal for space that will evolve as user requirements adapt to a changing world environment. The third product is the framework of a process that, when fully developed, will provide essential information to key decision makers for space systems acquisition in order to achieve the AMSSA goal. It is a categorical imperative that military space planners develop space systems that will act as true force multipliers. AMSSA provides the philosophy, process, and architecture that, when integrated with the DOD requirements and acquisition procedures, can yield an assured mission support capability from space to the combatant commanders. An important feature of the AMSSA initiative is the participation by every organization that has a role or interest in space systems development and operation. With continued community involvement, the concept of the AMSSA will become a reality. In summary, AMSSA offers a better way to think about space (philosophy) that can lead to the effective utilization of limited resources (process) with an infrastructure designed to meet the future space needs (architecture) of our combat forces.

  3. Supporting hemodialysis patients: A phenomenological study

    PubMed Central

    Shahgholian, Nahid; Yousefi, Hojatollah

    2015-01-01

    Background: Chronic renal disease and hemodialysis cause numerous psychological, social, cultural, and spiritual challenges for both patients and their families. Overcoming these challenges is possible only through providing holistic support for the patients. Today, despite the support provided by family and professional caregivers for the patients, patients still express dissatisfaction with the support provided and believe it to be inadequate. In fact, patients and family caregivers and healthcare practitioners seem to have different understandings of the notion of support. Thus, the researcher decided to examine the concept of support from the viewpoint of hemodialysis patients. Materials and Methods: This descriptive phenomenological research was conducted on 17 patients with end-stage renal disease (ESRD) who were undergoing hemodialysis. Purposive sampling was performed and continued until data saturation. Data were collected through 30–60 min unstructured interviews and analyzed using Colaizzi's method. Results: From the analysis of data, 4 themes (psychological support, accompaniment, social support, and spiritual support) and 11 sub-themes were obtained. Psychological support consisted of two sub-themes of psychological support by healthcare practitioners and emotional support by family and relatives. Accompaniment included three sub-themes of assistance in transportation, providing and using medicine, and daily activities. Social support was identified with four sub-themes of promotion of the society's understanding of the patients’ condition, improvement of communication with others, the need for employment, and independence. Spiritual support was identified with two sub-themes of the need for faith and trust in God or Imams and the need to resolve spiritual contradictions. Conclusion: The results showed that from the viewpoint of the participants, the concept of support consisted of psychological support, social support, accompanying the patient

  4. A phase 1 dose-escalation and expansion study of binimetinib (MEK162), a potent and selective oral MEK1/2 inhibitor

    PubMed Central

    Bendell, Johanna C; Javle, Milind; Bekaii-Saab, Tanios S; Finn, Richard S; Wainberg, Zev A; Laheru, Daniel A; Weekes, Colin D; Tan, Benjamin R; Khan, Gazala N; Zalupski, Mark M; Infante, Jeffrey R; Jones, Suzanne; Papadopoulos, Kyriakos P; Tolcher, Anthony W; Chavira, Renae E; Christy-Bittel, Janna L; Barrett, Emma; Patnaik, Amita

    2017-01-01

    Background: Binimetinib (MEK162; ARRY-438162) is a potent and selective oral MEK 1/2 inhibitor. This phase 1 study determined the maximum tolerated dose (MTD), safety, pharmacokinetic and pharmacodynamic profiles, and preliminary anti-tumour activity of binimetinib in patients with advanced solid tumours, with expansion cohorts of patients with biliary cancer or KRAS- or BRAF-mutant colorectal cancer. Methods: Binimetinib was administered twice daily. Expansion cohorts were enroled after MTD determination following a 3+3 dose-escalation design. Pharmacokinetic properties were determined from plasma samples. Tumour samples were assessed for mutations in RAS, RAF, and other relevant genes. Pharmacodynamic properties were evaluated in serum and skin punch biopsy samples. Results: Ninety-three patients received binimetinib (dose-escalation phase, 19; expansion, 74). The MTD was 60 mg twice daily, with dose-limiting adverse events (AEs) of dermatitis acneiform and chorioretinopathy. The dose for expansion patients was subsequently decreased to 45 mg twice daily because of the frequency of treatment-related ocular toxicity at the MTD. Common AEs across all dose levels included rash (81%), nausea (56%), vomiting (52%), diarrhoea (51%), peripheral oedema (46%), and fatigue (43%); most were grade 1/2. Dose-proportional increases in binimetinib exposure were observed and target inhibition was demonstrated in serum and skin punch biopsy samples. Three patients with biliary cancer had objective responses (one complete and two partial). Conclusions: Binimetinib demonstrated a manageable safety profile, target inhibition, and dose-proportional exposure. The 45 mg twice daily dose was identified as the recommended phase 2 dose. The three objective responses in biliary cancer patients are encouraging and support further evaluation in this population. PMID:28152546

  5. An ERP study of passive creative conceptual expansion using a modified alternate uses task.

    PubMed

    Kröger, Sören; Rutter, Barbara; Hill, Holger; Windmann, Sabine; Hermann, Christiane; Abraham, Anna

    2013-08-21

    A novel ERP paradigm was employed to investigate conceptual expansion, a central component of creative thinking. Participants were presented with word pairs, consisting of everyday objects and uses for these objects, which had to be judged based on the two defining criteria of creative products: unusualness and appropriateness. Three subject-determined trial types resulted from this judgement: high unusual and low appropriate (nonsensical uses), low unusual and high appropriate (common uses), and high unusual and high appropriate (creative uses). Word pairs of the creative uses type are held to passively induce conceptual expansion. The N400 component was not specifically modulated by conceptual expansion but was, instead, generally responsive as a function of unusualness or novelty of the stimuli (nonsense=creative>common). Explorative analyses in a later time window (500-900 ms) revealed that ERP activity in this phase indexes appropriateness (nonsense>creative=common). In the discussion of these findings with reference to the literature on semantic cognition, both components are proposed as indexing processes relevant to conceptual expansion as they are selectively involved in the encoding and integration of a newly established semantic connection between two previously unrelated concepts.

  6. Ultraprecise Studies of the Thermal Expansion Coefficient of Diamond using Backscattering X-ray Diffraction

    SciTech Connect

    S Stoupin; Y Shvydko

    2011-12-31

    The linear thermal expansion coefficient of diamond crystals of type IIa and type Ia was measured in the temperature range from 10 to 295 K. Neither negative thermal expansion nor any substantial difference in the thermal expansion coefficient in crystals of the different types were observed. An empirical expression was obtained that approximates the temperature dependence of the thermal expansion coefficient of diamond. The T{sup 3} temperature dependence of a Debye solid holds below {approx}100 K with an accuracy of {approx}10{sup -8} K{sup -1}. A slight increase in the value of the lattice parameter was found for the Ia-type crystal, which suggests lattice dilatation by nitrogen impurity. The measurements were performed using Bragg diffraction in backscattering from diamond crystals of highly monochromatic 23.7 keV x rays with the recently demonstrated high relative accuracy of 1.2 x 10{sup -8} in the determination of the lattice parameter [S. Stoupin and Yu. Shvyd'ko Phys. Rev. Lett. 104 085901 (2010)].

  7. A study of the mechanism of laser welding defects in low thermal expansion superalloy GH909

    SciTech Connect

    Yan, Fei; Wang, Chunming Wang, Yajun; Hu, Xiyuan; Wang, Tianjiao; Li, Jianmin; Li, Guozhu

    2013-04-15

    In this paper, we describe experimental laser welding of low-thermal-expansion superalloy GH909. The main welding defects of GH909 by laser in the weld are liquation cracks and porosities, including hydrogen and carbon monoxide porosity. The forming mechanism of laser welding defects was investigated. This investigation was conducted using an optical microscope, scanning electron microscope, energy diffraction spectrum, X-ray diffractometer and other methodologies. The results demonstrated that porosities appearing in the central weld were related to incomplete removal of oxide film on the surface of the welding samples. The porosities produced by these bubbles were formed as a result of residual hydrogen or oxygenium in the weld. These elements failed to escape from the weld since laser welding has both a rapid welding speed and cooling rate. The emerging crack in the heat affected zone is a liquation crack and extends along the grain boundary as a result of composition segregation. Laves–Ni{sub 2}Ti phase with low melting point is a harmful phase, and the stress causes grain boundaries to liquefy, migrate and even crack. Removing the oxides on the surface of the samples before welding and carefully controlling technological parameters can reduce welding defects and improve formation of the GH909 alloy weld. - Highlights: ► It is a new process for the forming of GH909 alloy via laser welding. ► The forming mechanism of laser welding defects in GH909 has been studied. ► It may be a means to improve the efficiency of aircraft engine production.

  8. Re-expansion of atelectasis during general anaesthesia: a computed tomography study.

    PubMed

    Rothen, H U; Sporre, B; Engberg, G; Wegenius, G; Hedenstierna, G

    1993-12-01

    Formation of atelectasis is one mechanism of impaired gas exchange during general anaesthesia. We have studied manoeuvres to re-expand such atelectasis in 16 consecutive, anaesthetized adults with healthy lungs. In group 1 (10 patients), the lungs were inflated stepwise to an airway pressure (Paw) of 10, 20, 30 and 40 cm H2O. In group 2 (six patients), three repeated inflations up to Paw = 30 cm H2O were followed by one inflation to 40 cm H2O. Atelectasis was assessed by analysis of computed x-ray tomography (CT). In group 1 the mean area of atelectasis in the CT scan at the level of the right diaphragm was 6.4 cm2 at Paw = 0 cm H2O, 5.9 cm2 at 20 cm H2O, 3.5 cm2 at 30 cm H2O and 0.8 cm2 at 40 cm H2O. A Paw of 20 cm H2O corresponds approximately to inflation with twice the tidal volume. In group 2 the mean area of atelectasis was 9.0 cm2 at Paw = 0 cm H2O and 4.2 cm2 after the first inflation to 30 cm H2O. Repeated inflations did not add to re-expansion of atelectasis. The final inflation (Paw = 40 cm H2O) virtually eliminated the atelectasis. We conclude that, after induction of anaesthesia, the amount of atelectasis was not reduced by inflation of the lungs with a conventional tidal volume or with a double tidal volume ("sigg"). An inflation to vital capacity (Paw = 40 cm H2O), however, re-expanded virtually all atelectatic lung tissue.

  9. Defined Essential 8™ Medium and Vitronectin Efficiently Support Scalable Xeno-Free Expansion of Human Induced Pluripotent Stem Cells in Stirred Microcarrier Culture Systems

    PubMed Central

    Badenes, Sara M.; Fernandes, Tiago G.; Cordeiro, Cláudia S. M.; Boucher, Shayne; Kuninger, David; Vemuri, Mohan C.; Diogo, Maria Margarida; Cabral, Joaquim M. S.

    2016-01-01

    Human induced pluripotent stem (hiPS) cell culture using Essential 8™ xeno-free medium and the defined xeno-free matrix vitronectin was successfully implemented under adherent conditions. This matrix was able to support hiPS cell expansion either in coated plates or on polystyrene-coated microcarriers, while maintaining hiPS cell functionality and pluripotency. Importantly, scale-up of the microcarrier-based system was accomplished using a 50 mL spinner flask, under dynamic conditions. A three-level factorial design experiment was performed to identify optimal conditions in terms of a) initial cell density b) agitation speed, and c) to maximize cell yield in spinner flask cultures. A maximum cell yield of 3.5 is achieved by inoculating 55,000 cells/cm2 of microcarrier surface area and using 44 rpm, which generates a cell density of 1.4x106 cells/mL after 10 days of culture. After dynamic culture, hiPS cells maintained their typical morphology upon re-plating, exhibited pluripotency-associated marker expression as well as tri-lineage differentiation capability, which was verified by inducing their spontaneous differentiation through embryoid body formation, and subsequent downstream differentiation to specific lineages such as neural and cardiac fates was successfully accomplished. In conclusion, a scalable, robust and cost-effective xeno-free culture system was successfully developed and implemented for the scale-up production of hiPS cells. PMID:26999816

  10. Pleistocene glaciations, demographic expansion and subsequent isolation promoted morphological heterogeneity: A phylogeographic study of the alpine Rosa sericea complex (Rosaceae)

    PubMed Central

    Gao, Yun-Dong; Zhang, Yu; Gao, Xin-Fen; Zhu, Zhang-Ming

    2015-01-01

    While most temperate plants probably underwent glacial constriction to refugia and interglacial expansion, another type of interglacial refugia might have existed to maintain alpine plants during warm periods. To test this hypothesis, we applied phylogeographic methods to 763 individuals (62 populations) which belong to 7 taxonomically difficult species of the Rosa sericea complex distributed in alpine regions of the temperate and subtropical zones in eastern Asia. We used three chloroplast (cp) DNA fragments (trnL-trnF, ndhF-rpl32 and ndhJ-trnF) approximately 3,100 bp and nuclear microsatellite (nSSR) on eight sites to determine whether cold tolerant plants experienced expansion during the Pleistocene. The neutral test and mismatch distribution analysis (MDA) indicated that whole populations and major lineages of the Qinghai-Tibet Plateau (QTP) underwent expansion during the middle to late Pleistocene. Environmental niche modeling (ENM) indicates more suitable habitats during the Last Glacial Maximum (LGM) than at present. We concluded that the demographic history of R. sericea, which diverged in the middle Pleistocene, was mostly affected by climatic oscillations instead of by geographical barriers. The low genetic divergence, as well as the weak phylogenetic structure in the R. sericea complex both support treating this complex as a single taxon. PMID:26123942

  11. Geometrically frustrated GdInO3: An exotic system to study negative thermal expansion and spin-lattice coupling

    NASA Astrophysics Data System (ADS)

    Paul, Barnita; Chatterjee, Swastika; Roy, Anushree; Midya, A.; Mandal, P.; Grover, Vinita; Tyagi, A. K.

    2017-02-01

    In this article, we report negative thermal expansion and spin frustration in hexagonal GdInO3. Rietveld refinements of the x-ray diffraction patterns reveal that the negative thermal expansion in the temperature range of 50-100 K stems from the triangular lattice of Gd3 + ions. The downward deviation of the low-temperature inverse susceptibility (χ-1) versus T plot from the Curie-Weiss law and the large value of the ratio, | θCW|/ TN>28 , where θCW and TN are respectively Curie-Weiss and Neel temperature, indicate a strong spin frustration, which inhibits long-range magnetic ordering down to 1.8 K. Magnetostriction measurements clearly demonstrate a spin-lattice coupling in the system. Low-temperature anomalous phonon softening, as obtained from temperature-dependent Raman measurements, also reveals the same. Our experimental observations are supported by first-principles density functional theory calculations of the electronic and phonon dispersion in GdInO3. The calculations suggest that the GdInO3 lattice is highly frustrated at low temperature. Further, the calculated normal mode frequencies of the Gd-related Γ point phonon modes reveal significant magnetoelastic coupling in this system. The competitive role of magnetic interaction energy and thermal stabilization energy in determining the change in interatomic distances is the possible origin for the negative thermal expansion in GdInO3 over a limited range of temperature.

  12. Effective potential of the three-dimensional Ising model: The pseudo-ɛ expansion study

    NASA Astrophysics Data System (ADS)

    Sokolov, A. I.; Kudlis, A.; Nikitina, M. A.

    2017-08-01

    The ratios R2k of renormalized coupling constants g2k that enter the effective potential and small-field equation of state acquire the universal values at criticality. They are calculated for the three-dimensional scalar λϕ4 field theory (3D Ising model) within the pseudo-ɛ expansion approach. Pseudo-ɛ expansions for the critical values of g6, g8, g10, R6 =g6 / g42 , R8 =g8 / g43 and R10 =g10 / g44 originating from the five-loop renormalization group (RG) series are derived. Pseudo-ɛ expansions for the sextic coupling have rapidly diminishing coefficients, so addressing Padé approximants yields proper numerical results. Use of Padé-Borel-Leroy and conformal mapping resummation techniques further improves the accuracy leading to the values R6* = 1.6488 and R6* = 1.6490 which are in a brilliant agreement with the result of advanced lattice calculations. For the octic coupling the numerical structure of the pseudo-ɛ expansions is less favorable. Nevertheless, the conform-Borel resummation gives R8* = 0.868, the number being close to the lattice estimate R8* = 0.871 and compatible with the result of 3D RG analysis R8* = 0.857. Pseudo-ɛ expansions for R10* and g10* are also found to have much smaller coefficients than those of the original RG series. They remain, however, fast growing and big enough to prevent obtaining fair numerical estimates.

  13. When enough is enough: how the decision was made to stop the FEAST trial: data and safety monitoring in an African trial of Fluid Expansion As Supportive Therapy (FEAST) for critically ill children.

    PubMed

    Todd, Jim; Heyderman, Robert S; Musoke, Philippa; Peto, Tim

    2013-03-26

    In resource-rich countries, bolus fluid expansion is routinely used for the treatment of poor perfusion and shock, but is less commonly used in many African settings. Controversial results from the recently completed FEAST (Fluid Expansion As Supportive Therapy) trial in African children have raised questions about the use of intravenous bolus fluid for the treatment of shock. Prior to the start of the trial, the Independent data monitoring committee (IDMC) developed stopping rules for the proof of benefit that bolus fluid resuscitation would bring. Although careful safety monitoring was put in place, there was less expectation that bolus fluid expansion would be harmful and differential stopping rules for harm were not formulated.In July 2010, two protocol amendments were agreed to increase the sample size from 2,880 to 3,600 children, and to increase bolus fluid administration. There was a non-significant trend against bolus treatment, but although the implications were discussed, the IDMC did not comment on the results, or on the amendments, in order to avoid inadvertent partial unblinding of the study.In January 2011, the trial was stopped for futility, as the combined intervention arms had significantly higher mortality (relative risk 1.46, 95% CI 1.13 to 1.90, P = 0.004) than the control arm. The stopping rule for proof of benefit was not achieved, and the IDMC stopped the trial with a lower level of significance (P = 0.01) due to futility and an increased risk of mortality from bolus fluid expansion in children enrolled in the trial. The basis for this decision was that the local standard of care was not to use bolus fluid for the care of children with shock in these African countries, and this was a different standard of care to that used in the UK. These decisions emphasize two important principles: firstly, the IDMC should avoid inadvertent unblinding of the trial by commenting on amendments, and secondly, when considering stopping a trial, the IDMC

  14. Studies in Public Library Government, Organization, and Support. Final Report.

    ERIC Educational Resources Information Center

    Garrison, Guy

    This report consists of six individual reports that were done by staff members at the Library Research Center as part of the overall project. In Part I, "Financing Public Library Expansion: Case Studies of Three Defeated Bond Issue Referendums," Ruth G. Lindahl and William S. Berner analyze defeated library bond issue referendums in…

  15. Study on the influences of interaction behaviors between multiple combustion-gas jets on expansion characteristics of Taylor cavities

    NASA Astrophysics Data System (ADS)

    Xue, Xiaochun; Yu, Yonggang; Zhang, Qi

    2015-10-01

    The purpose of this study is to investigate means of controlling the interior ballistic stability of a bulk-loaded propellant gun (BLPG). Experiments on the interaction of twin combustion gas jets and liquid medium in a cylindrical stepped-wall combustion chamber are conducted in detail to obtain time series processes of jet expansion, and a numerical simulation under the same working conditions is also conducted to verify the reliability of the numerical method by comparing numerical results and experimental results. From this, numerical simulations on mutual interference and expansion characteristics of multiple combustion gas jets (four, six, and eight jets) in liquid medium are carried out, and the distribution characteristic of pressure, velocity, temperature, and evolutionary processes of Taylor cavities and streamlines of jet flow field are obtained in detail. The results of numerical simulations show that when different numbers of combustion gas jets expand in liquid medium, there are two different types of vortices in the jet flow field, including corner vortices of liquid phase near the step and backflow vortices of gas phase within Taylor cavities. Because of these two types of vortices, the radial expansion characteristic of the jets is increased, while changing numbers of combustion gas jets can restrain Kelvin-Helmholtz instability to a certain degree in jet expansion processes, which can at last realize the goal of controlling the interior ballistic stability of a BLPG. The optimum method for both suppressing Kelvin-Helmholtz instability and promoting radial expansion of Taylor cavities can be determined by analyzing the change of characteristic parameters in a jet flow field.

  16. Different kinds of genetic markers permit inference of Paleolithic and Neolithic expansions in humans.

    PubMed

    Aimé, Carla; Austerlitz, Frédéric

    2017-02-01

    Recent population genetic studies have provided valuable insights on the demographic history of our species. However, some issues such as the dating of the first demographic expansions in human populations remain puzzling. Indeed, although a few genetic studies argued that the first human expansions were concomitant with the Neolithic transition, many others found signals of expansion events starting during the Palaeolithic. Here we performed a simulation study to show that these contradictory findings may result from the differences in the genetic markers used, especially if two successive expansion events occurred. For a large majority of replicates for each scenario tested, microsatellite data allow only detecting the recent expansion event in that case, whereas sequence data allow only detecting the ancient expansion. Combined with previous real data analyses, our results bring support to the ideas that (i) a first human expansions started during the Palaeolithic period, (ii) a second expansion event occurred later, concomitantly with the Neolithic transition.

  17. Study on changing the coefficient of thermal expansion (CTE) of dental porcelain.

    PubMed

    Jamaluddin, O; Zainal, A A

    2004-05-01

    Raising the thermal expansion coefficient (CTE) of dental porcelains is important to match the CTE of the ceramic material with the higher CTE of the metal inlay in dental restorations. The higher thermal expansion of the leucite phase increases the overall thermal expansion coefficient of the dental porcelain. Potassium nitrate (KNO3) additions in controlled percentages to the base dental porcelain formulation help in the formation of a leucite phase. The percentage added was 5,10 and 20 weight percent of leucite, respectively, to the total base frit composition. The change in CTE values was then investigated using a Linseis Dilatometer. A 20wt% KNO3 addition resulted in a CTE of 9.0 microm/m-K compared to the 7.7 microm/m-K CTE of the base composition. The microstructures observed under the scanning electron microscope (SEM) show a multiphase material with the leucite phases dispersed within a glassy matrix. The results suggest that higher CTEs in the dental porcelain are possible by increasing the KNO3- additions within the limits tested.

  18. Negative thermal expansion in crystals with the zincblende structure: an EXAFS study of CdTe.

    PubMed

    Abd el All, N; Dalba, G; Diop, D; Fornasini, P; Grisenti, R; Mathon, O; Rocca, F; Thiodjio Sendja, B; Vaccari, M

    2012-03-21

    The extended x-ray absorption fine structure (EXAFS) has been measured at both the K edges of cadmium and tellurium in CdTe, from liquid helium to room temperature, in order to investigate the local thermodynamic behaviour. The temperature dependences of the structural parameters obtained from the separate analysis of the two edges are perfectly consistent. The positive contribution to the thermal expansion due to the bond stretching and the negative contribution due to the tension effects are disentangled and quantified in terms of the bond thermal expansion and the perpendicular mean square relative displacement. The comparison with previous EXAFS results for Ge and CuCl shows that relevant correlations can be established between a number of local parameters measured by means of EXAFS and the properties of the lattice negative thermal expansion of tetrahedrally bonded semiconductors. The effective force constants derived from the EXAFS are compared with the force constants of a valence force field model. © 2012 IOP Publishing Ltd

  19. MATURATION IN ACTION: CRYOEM STUDY OF A VIRAL CAPSID CAUGHT DURING EXPANSION

    PubMed Central

    Veesler, D.; Quispe, J.; Grigorieff, N.; Potter, C.S.; Carragher, B.; Johnson, J. E.

    2012-01-01

    SUMMARY Bacteriophage HK97 maturation involves discrete intermediate particle forms, comparable to transitional states in protein folding, before reaching its mature form. The process starts by formation of a metastable prohead, poised for exothermic expansion triggered by DNA packaging. During maturation, the capsid subunit transitions from a strained to a canonical tertiary conformation and this has been postulated to be the driving mechanism for initiating expansion via switching hexameric capsomer architecture from skewed to 6-fold symmetric. We report the subnanometer electron-cryomicroscopy reconstruction of the HK97 first expansion intermediate prior to any crosslink formation. This form displays 6-fold symmetric hexamers, but, unexpectedly, capsid subunit tertiary structures exhibit distortions comparable to the prohead forms. We propose that release of this coat subunit strain acts in synergy with the first crosslinks to drive forward maturation. Finally, we speculate that the energetic features of this transition may result from increased stability of intermediates during maturation via enhanced inter-subunit interactions. PMID:22748764

  20. Thermal expansion of glassy polymers.

    PubMed

    Davy, K W; Braden, M

    1992-01-01

    The thermal expansion of a number of glassy polymers of interest in dentistry has been studied using a quartz dilatometer. In some cases, the expansion was linear and therefore the coefficient of thermal expansion readily determined. Other polymers exhibited non-linear behaviour and values appropriate to different temperature ranges are quoted. The linear coefficient of thermal expansion was, to a first approximation, a function of both the molar volume and van der Waal's volume of the repeating unit.

  1. Rapid maxillary expansion screws on the test bench--a pilot study.

    PubMed

    Muchitsch, Alfred Peter; Wendl, B; Winsauer, H; Pichelmayer, M; Payer, M

    2011-06-01

    In order to apply high, short-term forces during rapid maxillary expansion (RME) to the sutures of the maxilla with minimum loss of force and without causing unwanted side-effects (dentoalveolar tipping, etc.), the appliance should be as rigid as possible. The retention arms of the RME screws, representing a particularly vulnerable and stressed weak point of RME appliances, were the focus of this laboratory technical study. Retention arms of 16 types of RME screws comprising four arms and one with eight arms were examined using a three-point bending test. According to their ability to absorb the applied bending loads, the screws were classified in product groups from 1 (highest) to 6 (lowest). Fifteen of the tested retention arms (stainless steel), despite having the same diameter (1.48-1.49 mm), differed up to 69.81 per cent between the highest (288.0 N) and lowest (169.6 N) maximum force parameters and up to 66.40 per cent between the highest (3325.9 N/mm(2)) and lowest (1998.7 N/mm(2)) maximum bending stress parameters. Due to optimum formability, though reduced rigidity, a titanium screw for nickel-sensitive patients (group 6) displayed the lowest force and bending tension values. The stainless steel double arms of the eight-arm screw device welded on both ends displayed the highest force data. The mean ductilities of the groups with the most and least rigid single steel arms differed by 22.77 per cent. Statistical analysis using the Pearson correlation coefficient revealed a significant indirect correlation between ductility and both maximum force (r = -0.780, P < 0.001) and maximum bending stress (r = -0.778, P < 0.001). The SUPERscrews, the Tiger Dental four-arm screw (group 1), and the eight-arm screw displayed the highest capacity to absorb an applied bending load. The screws in groups 3-6 appear acceptable for RME during the pre-pubertal period, whereas in the pubertal and post-pubertal period, groups 1 and 2 are sufficient. In early adulthood only the

  2. 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.

  3. Patient-activated controlled expansion for breast reconstruction using controlled carbon dioxide inflation: confirmation of a feasibility study.

    PubMed

    Connell, Tony F

    2014-10-01

    Women with breast cancer or those at high risk of developing breast cancer because of familial history of the disease or genetic mutations are frequently indicated for therapeutic or prophylactic mastectomy. Prosthetic reconstruction of the breast with placement of tissue expanders followed by implants offers favorable aesthetic and psychological results while adding only minimal additional surgical intervention. This study describes the confirmatory phase of an earlier feasibility trial that involved seven women who successfully underwent patient-activated controlled expansion for breast reconstruction with 10 AeroForm patient-controlled tissue expanders. A prospective, open-label, single-arm, single-surgeon confirmatory study in Perth, Australia, evaluated outcomes of two-stage breast reconstruction using the investigational device. Each subject administered a preset 10-cc dose of carbon dioxide gas using a remote dosage controller, three times each day, with a 3-hour lockout between doses until full expansion was achieved. Thirty-three women with breast cancer, family history, or predisposition because of the BRCA1 or BRCA2 gene mutation underwent pedicled latissimus dorsi flap procedures with placement of 61 carbon dioxide-based tissue expanders. The mean number of days for subjects to achieve desired expansion was 17 ± 5. Operating the dosage controller was described by the surgeon as very easy in 94 percent of the cases and by 97 percent of the subjects. No serious adverse events were reported. This study confirms that the AeroForm breast tissue expander has demonstrated the ability to provide, relative to saline expanders, a needle-free, patient-controlled, convenient, and time-saving method of tissue expansion. Therapeutic, IV.

  4. Early Coverage, Access, Utilization, and Health Effects Associated With the Affordable Care Act Medicaid Expansions: A Quasi-experimental Study.

    PubMed

    Wherry, Laura R; Miller, Sarah

    2016-06-21

    In 2014, only 26 states and the District of Columbia chose to implement the Patient Protection and Affordable Care Act (ACA) Medicaid expansions for low-income adults. To evaluate whether the state Medicaid expansions were associated with changes in insurance coverage, access to and utilization of health care, and self-reported health. Comparison of outcomes before and after the expansions in states that did and did not expand Medicaid. United States. Citizens aged 19 to 64 years with family incomes below 138% of the federal poverty level in the 2010 to 2014 National Health Interview Surveys. Health insurance coverage (private, Medicaid, or none); improvements in coverage over the previous year; visits to physicians in general practice and specialists; hospitalizations and emergency department visits; skipped or delayed medical care; usual source of care; diagnoses of diabetes, high cholesterol, and hypertension; self-reported health; and depression. In the second half of 2014, adults in expansion states experienced increased health insurance (7.4 percentage points [95% CI, 3.4 to 11.3 percentage points]) and Medicaid (10.5 percentage points [CI, 6.5 to 14.5 percentage points]) coverage and better coverage than 1 year before (7.1 percentage points [CI, 2.7 to 11.5 percentage points]) compared with adults in nonexpansion states. Medicaid expansions were associated with increased visits to physicians in general practice (6.6 percentage points [CI, 1.3 to 12.0 percentage points]), overnight hospital stays (2.4 percentage points [CI, 0.7 to 4.2 percentage points]), and rates of diagnosis of diabetes (5.2 percentage points [CI, 2.4 to 8.1 percentage points]) and high cholesterol (5.7 percentage points [CI, 2.0 to 9.4 percentage points]). Changes in other outcomes were not statistically significant. Observational study may be susceptible to unmeasured confounders; reliance on self-reported data; limited post-ACA time frame provided information on short-term changes only

  5. The Thermal Expansion Of Feldspars

    NASA Astrophysics Data System (ADS)

    Hovis, G. L.; Medford, A.; Conlon, M.

    2009-12-01

    Hovis and others (1) investigated the thermal expansion of natural and synthetic AlSi3 feldspars and demonstrated that the coefficient of thermal expansion (α) decreases significantly, and linearly, with increasing room-temperature volume (VRT). In all such feldspars, therefore, chemical expansion limits thermal expansion. The scope of this work now has been broadened to include plagioclase and Ba-K feldspar crystalline solutions. X-ray powder diffraction data have been collected between room temperature and 925 °C on six plagioclase specimens ranging in composition from anorthite to oligoclase. When combined with thermal expansion data for albite (2,3,4) a steep linear trend of α as a function of VRT emerges, reflecting how small changes in composition dramatically affect expansion behavior. The thermal expansion data for five synthetic Ba-K feldspars ranging in composition from 20 to 100 mole percent celsian, combined with data for pure K-feldspar (3,4), show α-VRT relationships similar in nature to the plagioclase series, but with a slope and intercept different from the latter. Taken as a group all Al2Si2 feldspars, including anorthite and celsian from the present study along with Sr- (5) and Pb-feldspar (6) from other workers, show very limited thermal expansion that, unlike AlSi3 feldspars, has little dependence on the divalent-ion (or M-) site occupant. This apparently is due to the necessitated alternation of Al and Si in the tetrahedral sites of these minerals (7), which in turn locks the tetrahedral framework and makes the M-site occupant nearly irrelevant to expansion behavior. Indeed, in feldspar series with coupled chemical substitution it is the change away from a 1:1 Al:Si ratio that gives feldspars greater freedom to expand. Overall, the relationships among α, chemical composition, and room-temperature volume provide useful predictive tools for estimating feldspar thermal expansion and give insight into the controls of expansion behavior in

  6. The Social Integration of Supported Employees: A Qualitative Study.

    ERIC Educational Resources Information Center

    Hagner, David C.

    This study utilized qualitative methods to examine the social interactions that occur within supported employment settings between workers with disabilities and nondisabled co-workers. The study also examined the job supports at work settings, to understand the relationship between formal, job coach support services and natural job supports. Seven…

  7. Ring structure of a neutral gas cloud studied in a one-dimensional expansion into space

    NASA Technical Reports Server (NTRS)

    Davidson, R. E.

    1972-01-01

    A one dimensional treatment of the expansion of a gas cloud of uncharged particles into vacuum is discussed. It is determined that the whole cloud does not change from continuum to free molecular flow at the same time. Some regions of the cloud make the transition sooner than others. An explanation of the ring structure observed during barium cloud experiments is presented using this conclusion. An analysis of the velocity distributions for the two kinds of flow yields a velocity distribution for the whole cloud that exhibits ring structure.

  8. A Comparative Study of Supervised Learning as Applied to Acronym Expansion in Clinical Reports

    PubMed Central

    Joshi, Mahesh; Pakhomov, Serguei; Pedersen, Ted; Chute, Christopher G.

    2006-01-01

    Electronic medical records (EMR) constitute a valuable resource of patient specific information and are increasingly used for clinical practice and research. Acronyms present a challenge to retrieving information from the EMR because many acronyms are ambiguous with respect to their full form. In this paper we perform a comparative study of supervised acronym disambiguation in a corpus of clinical notes, using three machine learning algorithms: the naïve Bayes classifier, decision trees and Support Vector Machines (SVMs). Our training features include part-of-speech tags, unigrams and bigrams in the context of the ambiguous acronym. We find that the combination of these feature types results in consistently better accuracy than when they are used individually, regardless of the learning algorithm employed. The accuracy of all three methods when using all features consistently approaches or exceeds 90%, even when the baseline majority classifier is below 50%. PMID:17238371

  9. A comparative study of supervised learning as applied to acronym expansion in clinical reports.

    PubMed

    Joshi, Mahesh; Pakhomov, Serguei; Pedersen, Ted; Chute, Christopher G

    2006-01-01

    Electronic medical records (EMR) constitute a valuable resource of patient specific information and are increasingly used for clinical practice and research. Acronyms present a challenge to retrieving information from the EMR because many acronyms are ambiguous with respect to their full form. In this paper we perform a comparative study of supervised acronym disambiguation in a corpus of clinical notes, using three machine learning algorithms: the naïve Bayes classifier, decision trees and Support Vector Machines (SVMs). Our training features include part-of-speech tags, unigrams and bigrams in the context of the ambiguous acronym. We find that the combination of these feature types results in consistently better accuracy than when they are used individually, regardless of the learning algorithm employed. The accuracy of all three methods when using all features consistently approaches or exceeds 90%, even when the baseline majority classifier is below 50%.

  10. Thermal expansion and decomposition of jarosite: a high-temperature neutron diffraction study

    SciTech Connect

    Xu, Hongwu; Zhao, Yusheng; Vogel, Sven C; Hickmott, Donald D; Daemen, Luke L; Hartl, Monika A

    2009-01-01

    The structure of deuterated jarosite, KFe{sub 3}(SO{sub 4}){sub 2}(OD){sub 6}, was investigated using time-of-flight neutron diffraction up to its dehydroxylation temperature. Rietveld analysis reveals that with increasing temperature, its c dimension expands at a rate {approx}10 times greater than that for a. This anisotropy of thermal expansion is due to rapid increase in the thickness of the (001) sheet of [Fe(O,OH){sub 6}] octahedra and [SO{sub 4}] tetrahedra with increasing temperature. Fitting of the measured cell volumes yields a coefficient of thermal expansion, a = a{sub 0} + a{sub 1} T, where a{sub 0} = 1.01 x 10{sup -4} K{sup -1} and a{sub 1} = -1.15 x 10{sup -7} K{sup -2}. On heating, the hydrogen bonds, O1{hor_ellipsis}D-O3, through which the (001) octahedral-tetrahedral sheets are held together, become weakened, as reflected by an increase in the D{hor_ellipsis}O1 distance and a concomitant decrease in the O3-D distance with increasing temperature. On further heating to 575 K, jarosite starts to decompose into nanocrystalline yavapaiite and hematite (as well as water vapor), a direct result of the breaking of the hydrogen bonds that hold the jarosite structure together.

  11. An X-Ray and Radio Study of the Varying Expansion Velocities in Tycho's Supernova Remnant

    NASA Technical Reports Server (NTRS)

    Williams, Brian J.; Chomiuk, Laura; Hewitt, John W.; Blondin, John M.; Borkowski, Kazimierz J.; Ghavamian, Parviz; Petre, Robert; Reynolds, Stephen P.

    2016-01-01

    We present newly obtained X-ray and radio observations of Tycho's supernova remnant using Chandra and the Karl G. Jansky Very Large Array in 2015 and 2013/14, respectively. When combined with earlier epoch observations by these instruments, we now have time baselines for expansion measurements of the remnant of 12-15 years in the X-rays and 30 years in the radio. The remnant's large angular size allows for proper motion measurements at many locations around the periphery of the blast wave. Consistent with earlier measurements, we find a clear gradient in the expansion velocity of the remnant, despite its round shape. The proper motions on the western and southwestern sides of the remnant are about a factor of two higher than those in the east and northeast. We showed in an earlier work that this is related to an offset of the explosion site from the geometric center of the remnant due to a density gradient in the ISM, and using our refined measurements reported here, we find that this offset is approximately 23? toward the northeast. An explosion center offset in such a circular remnant has implications for searches for progenitor companions in other remnants.

  12. Mapping palm oil expansion using SAR to study the impact on the CO2 cycle

    NASA Astrophysics Data System (ADS)

    Pohl, Christine

    2014-06-01

    With Malaysia being the second largest palm oil producer in the world and the fact that palm oil ranks first in vegetable oil production on the world market the palm oil industry became an important factor in the country. Along with the expansion of palm oil across the nation causing deforestation of natural rain forest and conversion of peat land into plantation land there are several factors causing a tremendous increase in carbon dioxide (CO2) emissions. Main causes of CO2 emission apart from deforestation and peat-land conversion are the fires to create plantation land plus the fires burning waste products of the plantations itself. This paper describes a project that aims at the development of a remote sensing monitoring system to allow a continuous observation of oil palm plantation activities and expansion in order to be able to quantify CO2 emissions. The research concentrates on developing a spaceborne synthetic aperture radar information extraction system for palm oil plantations in the Tropics. This will lead to objective figures that can be used internationally to create a policy implementation plan to sustainably reduce CO2 emission in the future.

  13. An X-Ray and Radio Study of the Varying Expansion Velocities in Tycho's Supernova Remnant

    NASA Technical Reports Server (NTRS)

    Williams, Brian J.; Chomiuk, Laura; Hewitt, John W.; Blondin, John M.; Borkowski, Kazimierz J.; Ghavamian, Parviz; Petre, Robert; Reynolds, Stephen P.

    2016-01-01

    We present newly obtained X-ray and radio observations of Tycho's supernova remnant using Chandra and the Karl G. Jansky Very Large Array in 2015 and 2013/14, respectively. When combined with earlier epoch observations by these instruments, we now have time baselines for expansion measurements of the remnant of 12-15 year in the X-rays and 30 year in the radio. The remnant's large angular size allows for proper motion measurements at many locations around the periphery of the blast wave. We find, consistent with earlier measurements, a clear gradient in the expansion velocity of the remnant, despite its round shape. The proper motions on the western and southwestern sides of the remnant are about a factor of two higher than those in the east and northeast. We showed in an earlier work that this is related to an offset of the explosion site from the geometric center of the remnant due to a density gradient in the ISM, and using our refined measurements reported here, we find that this offset is approximately 23'' towards the northeast. An explosion center offset in such a circular remnant has implications for searches for progenitor companions in other remnants.

  14. An X-Ray and Radio Study of the Varying Expansion Velocities in Tycho's Supernova Remnant

    NASA Technical Reports Server (NTRS)

    Williams, Brian J.; Chomiuk, Laura; Hewitt, John W.; Blondin, John M.; Borkowski, Kazimierz J.; Ghavamian, Parviz; Petre, Robert; Reynolds, Stephen P.

    2016-01-01

    We present newly obtained X-ray and radio observations of Tycho's supernova remnant using Chandra and the Karl G. Jansky Very Large Array in 2015 and 2013/14, respectively. When combined with earlier epoch observations by these instruments, we now have time baselines for expansion measurements of the remnant of 12-15 years in the X-rays and 30 years in the radio. The remnant's large angular size allows for proper motion measurements at many locations around the periphery of the blast wave. Consistent with earlier measurements, we find a clear gradient in the expansion velocity of the remnant, despite its round shape. The proper motions on the western and southwestern sides of the remnant are about a factor of two higher than those in the east and northeast. We showed in an earlier work that this is related to an offset of the explosion site from the geometric center of the remnant due to a density gradient in the ISM, and using our refined measurements reported here, we find that this offset is approximately 23? toward the northeast. An explosion center offset in such a circular remnant has implications for searches for progenitor companions in other remnants.

  15. Study on sludge expansion during treatment of salad oil manufacturing wastewater by yeast.

    PubMed

    Zheng, S; Yang, M; Lv, W; Liu, F

    2001-05-01

    Five yeast strains, namely Rhodotorula rubra, Candida tropicalis, Candida utilis, Candida boidinii, Trichosporon cutaneum, were isolated from soil spots of a salad oil factory, and applied for continuous treatment of salad oil manufacturing wastewater. The oil and COD removal performance of the mixed cultures were comparable to the results other researchers obtained. Sludge expansion, accompanied with sludge morphology change from pseudomycelia to true mycelia, occurred during continuous treatment of wastewater. The true mycelia dominated sludge had a much higher water content and SVI value than that of the yeast pure cultures, although the two kinds of sludge had similar oil removal performance. A mold, Geotrichum candidum, was isolated from the expanded sludge, and was suspected to be a reason for sludge expansion. Addition of 0.3% sodium propionate into batch cultures degraded SVI value from around 100 to 60. In a continuous running, addition of 10 mg l-1 sodium hypochlorite decreased SVI value from over 200 to below 100. The yeast activity, however, was weakened to a large extent at the same time.

  16. Anomalous thermal expansion in rare-earth gallium perovskites: a comprehensive powder diffraction study

    NASA Astrophysics Data System (ADS)

    Senyshyn, A.; Trots, D. M.; Engel, J. M.; Vasylechko, L.; Ehrenberg, H.; Hansen, T.; Berkowski, M.; Fuess, H.

    2009-04-01

    Crystal structures of rare-earth gallium perovskites LaGaO3, PrGaO3, NdGaO3 and Pr1-xNdxGaO3 (x = 0.25, 0.50, 0.75) solid solutions were investigated in the temperature range 12-300 K by high-resolution powder diffraction using synchrotron or neutron radiation. The previously reported negative thermal expansion in the b direction of the PrGaO3 lattice has been found to be persistent in Pr1-xNdxGaO3 solid solutions and its magnitude has been revealed as proportional to the amount of praseodymium. Evaluation of the obtained temperature evolution of cell dimensions indicated a weak anomalous behaviour of the b lattice parameter in NdGaO3, and its origin is supposed to be the same as in PrGaO3, i.e. a coupling of the crystal electric field levels with phonon excitations of about 23-25 meV energy. The performed bond length analysis revealed an anomalous behaviour of both LnO12 (Ln—rare-earth) and GaO6 coordination polyhedra, which can be a structural manifestation of anomalous thermal expansion in the considered compounds.

  17. Study on three-dimensional expansion characteristics of four wall combustion-gas jets in confined liquid space

    NASA Astrophysics Data System (ADS)

    Hu, Zhitao; Yu, Yonggang

    2017-04-01

    To explore further the launch mechanism of the new underwater launching technology proposed in this paper, the expansion characteristics of four wall combustion-gas jets in confined liquid space must be studied firstly. The experimental device is designed, and the high-speed digital photographic system is adopted to obtain the expansion sequence processes of Taylor cavities formed by the four wall jets. Meanwhile, the influence of the injection pressure on the axial expansion property of the four wall jets is discussed. Based on the experiments, a three-dimensional unsteady mathematical model is established to simulate the turbulent flow process of the four wall jets expanding in liquid, and the temporal and spatial distribution laws of phase, pressure, temperature, and velocity and the evolution rules of vortices are illustrated in detail. Results show that, accompanied by the jets expanding downstream, the four wall combustion-gas jets get close to each other and achieve convergence eventually under induction of the interference effect between multiple jets. Meanwhile, the heads of the Taylor cavities separate from the observation chamber wall and offset to the central axis of the observation chamber with time going on. The numerical simulation results of the four wall combustion-gas jets coincide well with the experimental data.

  18. Study on three-dimensional expansion characteristics of four wall combustion-gas jets in confined liquid space

    NASA Astrophysics Data System (ADS)

    Hu, Zhitao; Yu, Yonggang

    2017-03-01

    To explore further the launch mechanism of the new underwater launching technology proposed in this paper, the expansion characteristics of four wall combustion-gas jets in confined liquid space must be studied firstly. The experimental device is designed, and the high-speed digital photographic system is adopted to obtain the expansion sequence processes of Taylor cavities formed by the four wall jets. Meanwhile, the influence of the injection pressure on the axial expansion property of the four wall jets is discussed. Based on the experiments, a three-dimensional unsteady mathematical model is established to simulate the turbulent flow process of the four wall jets expanding in liquid, and the temporal and spatial distribution laws of phase, pressure, temperature, and velocity and the evolution rules of vortices are illustrated in detail. Results show that, accompanied by the jets expanding downstream, the four wall combustion-gas jets get close to each other and achieve convergence eventually under induction of the interference effect between multiple jets. Meanwhile, the heads of the Taylor cavities separate from the observation chamber wall and offset to the central axis of the observation chamber with time going on. The numerical simulation results of the four wall combustion-gas jets coincide well with the experimental data.

  19. A comparative study of arc behaviour in an auto-expansion circuit breaker with different arc durations

    NASA Astrophysics Data System (ADS)

    Pei, Y.; Zhong, J.; Zhang, J.; Yan, J. D.

    2014-08-01

    A computational study of the thermal interruption performance of a 145 kV, 60 Hz auto-expansion circuit breaker has been carried out. The pressure peak in the expansion volume has a delay of 2.8-3.4 ms with reference to the current peak when the arc duration varies. A reasonable indicator of the interruption environment is the average mass flux in the main nozzle. The short arc duration case (12.25 ms) is the most difficult case with the lowest critical rate of rise of recovery voltage (RRRV) of 10 kV µs-1, just above the initial system applied RRRV of 9 kV µs-1. This is a result of an insufficient gas flow cross sectional area between the live contact and the main nozzle to develop rapid gas flow for arc cooling. The auxiliary nozzle plays two roles. It provides blockage in the high current phase to reduce gas exhaustion from the main nozzle into the hollow contact; after current zero the hollow contact shares a considerable portion of the system recovery voltage, especially for the short arc duration case (36%). Therefore the proper design and use of an auxiliary nozzle is key to enhancing the thermal interruption capability of high voltage auto-expansion circuit breakers.

  20. Association of Hypertension with Abdominal Aortic Aneurysm Expansion.

    PubMed

    Takagi, Hisato; Umemoto, Takuya

    2017-02-01

    Hypertension is positively associated with abdominal aortic aneurysm (AAA) presence, which supports a hypothesis that hypertension may also be positively associated with AAA expansion. To determine whether hypertension is associated with AAA expansion, we reviewed currently available studies with a systematic literature search and meta-analytic estimate. Databases including MEDLINE and EMBASE were searched through July 2015 using Web-based search engines (PubMed and OVID). Studies considered for inclusion met the following criteria: the study population was AAA patients with and without hypertension, and outcomes included data regarding AAA expansion. For each study, expansion rates in both the hypertensive and nonhypertensive groups were used to generate standardized mean differences (SMDs) and 95% confidence intervals (CIs). Of 614 potentially relevant publications screened initially, we identified 20 eligible studies including data on 6,619 AAA patients. No individual study indicated a statistically significant (positive or negative) association of hypertension with AAA expansion rates. A pooled analysis of all the 20 studies demonstrated that hypertension was not associated with AAA expansion rates in the fixed-effect model (SMD 0.03, 95% CI -0.01 to 0.17, P = 0.19). There was no evidence of significant publication bias. Hypertension is not associated with AAA expansion. Further investigations would be required to elucidate why hypertension is not associated with AAA expansion despite its positive association with AAA presence. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. The effect of surgically assisted rapid maxillary expansion on sleep architecture: an exploratory risk study in healthy young adults.

    PubMed

    Bach, N; Tuomilehto, H; Gauthier, C; Papadakis, A; Remise, C; Lavigne, F; Lavigne, G J; Huynh, N

    2013-11-01

    Maxillary transverse deficiencies (MTD) cause malocclusions. Rapid maxillary expansion treatment is commonly used treatment for correcting such deficiencies and has been found to be effective in improving respiration and sleep architecture in children with obstructive sleep apnoea (OSA). However, thus far, the effect of surgically assisted rapid maxillary expansion (SARME) treatment on sleep architecture and breathing of normal subjects has not been assessed. We hypothesised that sleep quality will improve after maxillary expansion treatment. The objective of this study is to access the effect of maxillary expansion treatment on sleep structure and respiratory functions in healthy young adults with severe MTD. This is a prospective and exploratory clinical study. Twenty-eight consecutive young adult patients (15 males and 13 females, mean age 20·6 ± 5·8 years) presenting with severe MTD at the orthodontic examination were recruited into the study. All the participants underwent a standardised SARME procedure (mean expansion 6·5 ± 1·8 and 8·2 ± 1·8 mm, intercanine and intermolar distance, respectively) to correct malocclusion caused by MTD. An overnight in-laboratory polysomnography, before and after the treatment, was performed. The mean follow-up time was 9 months. The main outcome parameters were the changes in sleep architecture, including sleep stages, arousals, slow-wave activity (SWA) and respiratory variables. Before surgery, young adult patients with MTD presented no evidence of sleep breathing problems. At baseline sleep recording, 7 of 28 (25%) had apnoea-hypopnoea index (AHI) ≥ 5 events per hour. No negative effect of the SARME was observed in questionnaires or sleep laboratory parameters. In the patients with a higher baseline AHI (AHI ≥ 5 h of sleep), we observed a reduction in AHI after surgical treatment (P = 0·028). SARME did not have a negative effect on any sleep or respiration parameters in healthy young individuals

  2. Supported Employment for Young People with Intellectual Disabilities Facilitated through Peer Support: A Pilot Study

    ERIC Educational Resources Information Center

    Kaehne, Axel; Beyer, Stephen

    2013-01-01

    The article reports the evaluation of a small-scale-supported employment project in a local authority in England. The study examined whether or not the peer support model could be used to deliver supported employment to a group of young people with intellectual disabilities. We utilised a mixed-method approach involving activity data, family…

  3. Supported Employment for Young People with Intellectual Disabilities Facilitated through Peer Support: A Pilot Study

    ERIC Educational Resources Information Center

    Kaehne, Axel; Beyer, Stephen

    2013-01-01

    The article reports the evaluation of a small-scale-supported employment project in a local authority in England. The study examined whether or not the peer support model could be used to deliver supported employment to a group of young people with intellectual disabilities. We utilised a mixed-method approach involving activity data, family…

  4. Proactive and Adaptive Decision Support Study (PDS)

    DTIC Science & Technology

    2014-08-31

    Arlington, VA 22203-1995 703-696-2875 jeffrey.g.morrison@navy.mil Report Prepared By: Thomas G. Allen Boston Fusion Corp. 1 Van de Graaff Drive...7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Boston Fusion Corp.,1 Van de Graaff Drive, Suite 107,Burlington,MA,01803 8. PERFORMING...During August, the principal activities for Boston Fusion were related to the preparation for, and attendance at, the ONR Proactive Decision Support

  5. Experimental perfect-gas study of expansion-tube flow characteristics

    NASA Technical Reports Server (NTRS)

    Shinn, J. L.; Miller, C. G., III

    1978-01-01

    Results of an experimental investigation of expansion tube flow characteristics performed with helium test gas and acceleration gas are presented. The use of helium, eliminates complex real gas chemistry in the comparison of measured and predicted flow quantities. The driver gas was unheated helium at a nominal pressure of 33 MN sq m. The quiescent test gas pressure and quiescent acceleration gas pressure were varied from 0.7 to 50 kN/sq m and from 2.5 to 53 N/sq m, respectively. The effects of tube-wall boundary layer growth and finite secondary diaphragm opening time were examined through the variation of the quiescent gas pressures and secondary diaphragm thickness. Optimum operating conditions for helium test gas were also defined.

  6. Neutron scattering studies of the lattice expansion in a ferromagnetic superconductor UGe2 under pressure

    NASA Astrophysics Data System (ADS)

    Sokolov, D. A.; Ritz, R.; Pfleiderer, C.; Keller, T.; Huxley, A. D.

    2011-01-01

    We report high-resolution measurements of the lattice constants of UGe2 under pressure probed by a novel technique which utilises Larmor precession of polarised neutrons and surpasses the resolution of conventional scattering methods by two orders of magnitude. We confirm the presence of sharp anomalies in the lattice parameters at both the Curie and crossover temperatures at ambient pressure. We find that for pressure of 9.3 kbar the anomaly at the Curie temperature shifts to lower temperature in agreement with the known phase diagram. At 9.3 kbar, the pressure corresponding to an onset of superconductivity, the lattice expansion at the ferromagnetic transition is much stronger than at ambient pressure. The results indicate a complex evolution of the electronic structure of UGe2 with pressure and suggest that magneto-elastic coupling is strengthened at the pressures at which superconductivity appears; magneto-elastic coupling therefore may play an important role in stabilising superconductivity.

  7. Entanglement at a two-dimensional quantum critical point: a numerical linked-cluster expansion study.

    PubMed

    Kallin, Ann B; Hyatt, Katharine; Singh, Rajiv R P; Melko, Roger G

    2013-03-29

    We develop a method to calculate the bipartite entanglement entropy of quantum models, in the thermodynamic limit, using a numerical linked-cluster expansion (NLCE) involving only rectangular clusters. It is based on exact diagonalization of all n×m rectangular clusters at the interface between entangled subsystems A and B. We use it to obtain the Renyi entanglement entropy of the two-dimensional transverse field Ising model, for arbitrary real Renyi index α. Extrapolating these results as a function of the order of the calculation, we obtain universal pieces of the entanglement entropy associated with lines and corners at the quantum critical point. They show NLCE to be one of the few methods capable of accurately calculating universal properties of arbitrary Renyi entropies at higher dimensional critical points.

  8. Operation of Mammoth Pacific`s MP1-100 turbine with metastable, supersaturated expansions

    SciTech Connect

    Mines, G.L.

    1996-01-01

    INEL`s Heat Cycle Research project continues to develop a technology base for increasing use of moderate-temperature hydrothermal resources to generate electrical power. One concept is the use of metastable, supersaturated turbine expansions. These expansions support a supersaturated working fluid vapor; at equilibrium conditions, liquid condensate would be present during the turbine expansion process. Studies suggest that if these expansions do not adversely affect the turbine performance, up to 8-10% more power could be produced from a given geothermal fluid. Determining the impact of these expansions on turbine performance is the focus of the project investigations being reported.

  9. Study of the expansion characteristics of a pulsed plasma jet in air

    NASA Astrophysics Data System (ADS)

    Xuewei, ZHAO; Yonggang, YU; Shanshan, MANG; Xiaochun, XUE

    2017-04-01

    In the background of electrothermal-chemical (ETC) emission, an investigation has been conducted on the characteristics of a freely expanding pulsed plasma jet in air. The evolutionary process of the plasma jet is experimentally investigated using a piezoelectric pressure sensor and a digital high-speed video system. The variation relation in the extended volume, axial displacement and radial displacement of the pulsed plasma jet in atmosphere with time under different discharge voltages and jet breaking pressures is obtained. Based on experiments, a two-dimensional axisymmetric unsteady model is established to analyze the characteristics of the two-phase interface and the variation of flow-field parameters resulting from a pulsed plasma jet into air at a pressure of 1.5–3.5 MPa under three nozzle diameters (3 mm, 4 mm and 5 mm, respectively). The images of the plasma jet reveal a changing shape process, from a quasi-ellipsoid to a conical head and an elongated cylindrical tail. The axial displacement of the jet is always larger than that along the radial direction. The extended volume reveals a single peak distribution with time. Compared to the experiment, the numerical simulation agrees well with the experimental data. The parameters of the jet field mutate at the nozzle exit with a decrease in the parameter pulse near the nozzle, and become more and more gradual and close to environmental parameters. Increasing the injection pressure and nozzle diameter can increase the parameters of the flow field such as the expansion volume of the pulsed plasma jet, the size of the Mach disk and the pressure. In addition, the turbulent mixing in the expansion process is also enhanced.

  10. Study of the expansion characteristics of a pulsed plasma jet in air

    NASA Astrophysics Data System (ADS)

    Zhao, Xuewei; Yu, Yonggang; Mang, Shanshan; Xue, Xiaochun

    2017-04-01

    In the background of electrothermal-chemical (ETC) emission, an investigation has been conducted on the characteristics of a freely expanding pulsed plasma jet in air. The evolutionary process of the plasma jet is experimentally investigated using a piezoelectric pressure sensor and a digital high-speed video system. The variation relation in the extended volume, axial displacement and radial displacement of the pulsed plasma jet in atmosphere with time under different discharge voltages and jet breaking pressures is obtained. Based on experiments, a two-dimensional axisymmetric unsteady model is established to analyze the characteristics of the two-phase interface and the variation of flow-field parameters resulting from a pulsed plasma jet into air at a pressure of 1.5-3.5 MPa under three nozzle diameters (3 mm, 4 mm and 5 mm, respectively). The images of the plasma jet reveal a changing shape process, from a quasi-ellipsoid to a conical head and an elongated cylindrical tail. The axial displacement of the jet is always larger than that along the radial direction. The extended volume reveals a single peak distribution with time. Compared to the experiment, the numerical simulation agrees well with the experimental data. The parameters of the jet field mutate at the nozzle exit with a decrease in the parameter pulse near the nozzle, and become more and more gradual and close to environmental parameters. Increasing the injection pressure and nozzle diameter can increase the parameters of the flow field such as the expansion volume of the pulsed plasma jet, the size of the Mach disk and the pressure. In addition, the turbulent mixing in the expansion process is also enhanced.

  11. Medical association supports studies on marijuana therapy.

    PubMed

    1995-06-16

    The Gay and Lesbian Medical Association (GLMA) issued a statement on May 19, 1995, announcing its support of clinical trials of the therapeutic uses of marijuana. The U.S. Department of Health and Human Services has continued to resist permitting clinical trials of marijuana despite evidence that it can relieve symptoms of cancer, multiple sclerosis, and glaucoma. According to Dr. Alvin Novick, head of GLMA's AIDS Task Force, the Clinton Administration is being asked to not let its political fears blind it to the positive and legitimate scientific research designed to alleviate the suffering of thousands of AIDS patients.

  12. Space transportation system biomedical operations support study

    NASA Technical Reports Server (NTRS)

    White, S. C.

    1983-01-01

    The shift of the Space Transportation System (STS) flight tests of the orbiter vehicle to the preparation and flight of the payloads is discussed. Part of this change is the transition of the medical and life sciences aspects of the STS flight operations to reflect the new state. The medical operations, the life sciences flight experiments support requirements and the intramural research program expected to be at KSC during the operational flight period of the STS and a future space station are analyzed. The adequacy of available facilities, plans, and resources against these future needs are compared; revisions and/or alternatives where appropriate are proposed.

  13. Expansion of DSSTox: Leveraging public data to create a semantic cheminformatics resource with quality annotations for support of U.S. EPA applications. (American Chemical Society)

    EPA Science Inventory

    The expansion of chemical-bioassay data in the public domain is a boon to science; however, the difficulty in establishing accurate linkages from CAS registry number (CASRN) to structure, or for properly annotating names and synonyms for a particular structure is well known. DSS...

  14. Expansion of DSSTox: Leveraging public data to create a semantic cheminformatics resource with quality annotations for support of U.S. EPA applications. (American Chemical Society)

    EPA Science Inventory

    The expansion of chemical-bioassay data in the public domain is a boon to science; however, the difficulty in establishing accurate linkages from CAS registry number (CASRN) to structure, or for properly annotating names and synonyms for a particular structure is well known. DSS...

  15. Expansion Microscopy

    PubMed Central

    Chen, Fei; Tillberg, Paul W.; Boyden, Edward S.

    2014-01-01

    In optical microscopy, fine structural details are resolved by using refraction to magnify images of a specimen. Here we report the discovery that, by synthesizing a swellable polymer network within a specimen, it can be physically expanded, resulting in physical magnification. By covalently anchoring specific labels located within the specimen directly to the polymer network, labels spaced closer than the optical diffraction limit can be isotropically separated and optically resolved, a process we call expansion microscopy (ExM). Thus, this process can be used to perform scalable super-resolution microscopy with diffraction-limited microscopes. We demonstrate ExM with effective ~70 nm lateral resolution in both cultured cells and brain tissue, performing three-color super-resolution imaging of ~107 μm3 of the mouse hippocampus with a conventional confocal microscope. PMID:25592419

  16. Theoretical study of negative thermal expansion mechanism of ZnF{sub 2}

    SciTech Connect

    Wang, Lei; Yuan, Peng-Fei; Wang, Fei; Sun, Qiang; Liang, Er-Jun; Jia, Yu

    2012-05-15

    Graphical abstract: ZnF{sub 2} owns open-framework structure and its negative thermal expansion (NTE) properties have been confirmed using a first-principles calculation. According to the phonon eigenvectors and group theory analysis, the lowest frequency (48.9 cm{sup -1}, B{sub 1g} mode) rigid unit mode (RUM) of ZnF{sub 6} causes a rotary coupling between two adjacent octahedrons and makes the Zn-Zn distance shorter, which is considered to be most responsible for the NTE properties of ZnF{sub 2}. Highlights: Black-Right-Pointing-Pointer The NTE properties of ZnF{sub 2} are confirmed using a first-principles calculation. Black-Right-Pointing-Pointer Phonon mode classification and Grueneisen parameters are systematically presented. Black-Right-Pointing-Pointer The rigid unit mode causes a rotary coupling and makes the Zn-Zn distance shorter. Black-Right-Pointing-Pointer The optical branch with the lowest frequency is most responsible for the NTE. -- Abstract: ZnF{sub 2} is reported to exhibit negative thermal expansion (NTE) at lower temperatures very recently. In this article, we present the electronic and NTE properties of ZnF{sub 2} using a first-principles calculation. Our results show that ZnF{sub 2} is an insulator with a direct band gap and a strong hybridization occurs between Zn-3p, 4s and F-2p states. The related calculations on NTE properties are obtained within the quasi-harmonic approximation. The resulting relationship between volume and temperature confirms the NTE properties. Besides, we discuss the NTE mechanism in accordance to phonon vibrational modes. The phonon vibrational modes contributing to the NTE are singled out by Grueneisen parameters and all these modes are low-frequency optical phonons. The lowest frequency rigid unit mode (RUM) of ZnF{sub 6} causes a rotary coupling between two adjacent octahedrons and makes the Zn-Zn distance shorter, which is most responsible for the NTE properties of ZnF{sub 2}.

  17. Repulsive force support system feasibility study

    NASA Technical Reports Server (NTRS)

    Boom, R. W.; Abdelsalam, M. K.; Eyssa, Y. M.; Mcintosh, G. E.

    1987-01-01

    A new concept in magnetic levitation and control is introduced for levitation above a plane. A set of five vertical solenoid magnets mounted flush below the plane supports and controls the model in five degrees of freedom. The compact system of levitation coils is contained in a space 2.4 m (96 in) diameter by 1 m (40 in) deep with the top of the levitation system 0.9 m (36 in) below the center line of the suspended model. The levitated model has a permanent magnet core held in position by the five parallel superconductive solenoids symmetrically located in a circle. The control and positioning system continuously corrects for model position in five dimensions using computer current pulses superimposed on the levitation coil base currents. The conceptual designs include: superconductive and Nd-Fe-B permanent magnet model cores and levitation solenoids of either superconductive, cryoresistive, or room temperature windings.

  18. Supporting Calculations For Submerged Bed Scrubber Condensate Disposal Preconceptual Study

    SciTech Connect

    Pajunen, A. J.; Tedeschi, A. R.

    2012-09-18

    This document provides supporting calculations for the preparation of the Submerged Bed Scrubber Condensate Disposal Preconceptual Study report The supporting calculations include equipment sizing, Hazard Category determination, and LAW Melter Decontamination Factor Adjustments.

  19. Study on Electricity Business Expansion and Electricity Sales Based on Seasonal Adjustment

    NASA Astrophysics Data System (ADS)

    Zhang, Yumin; Han, Xueshan; Wang, Yong; Zhang, Li; Yang, Guangsen; Sun, Donglei; Wang, Bolun

    2017-05-01

    [1] proposed a novel analysis and forecast method of electricity business expansion based on Seasonal Adjustment, we extend this work to include the effect the micro and macro aspects, respectively. From micro aspect, we introduce the concept of load factor to forecast the stable value of electricity consumption of single new consumer after the installation of new capacity of the high-voltage transformer. From macro aspects, considering the growth of business expanding is also stimulated by the growth of electricity sales, it is necessary to analyse the antecedent relationship between business expanding and electricity sales. First, forecast electricity consumption of customer group and release rules of expanding capacity, respectively. Second, contrast the degree of fitting and prediction accuracy to find out the antecedence relationship and analyse the reason. Also, it can be used as a contrast to observe the influence of customer group in different ranges on the prediction precision. Finally, Simulation results indicate that the proposed method is accurate to help determine the value of expanding capacity and electricity consumption.

  20. An outdoor noise propagation study to predict the effect of a power plant expansion

    NASA Astrophysics Data System (ADS)

    Brasovan, Philip J.; Carney, Melinda J.; Cheenne, Dominique J.

    2005-04-01

    The results of an outdoor noise propagation model using CadnaA were compared to test data obtained on-site. The subject property is the central utility plant of a hospital located in Milwaukee, scheduled to be expanded with the addition of cooling towers. The modeled area was 400 m squared with a resolution grid of 2 m squared. The model was used to validate the observed test data as well as to predict the anticipated noise levels at completion of the expansion. A total of 11 points were investigated and the predicted data were found to match the test values within 2 dB at many locations. The data from the model show that the anticipated noise levels at the East property line will exceed those mandated by local ordinances by 3 dB. The model also predicts that the addition of a three meter absorbing barrier and the use of reduced noise fans for the six cell cooling system will bring the overall noise level from the system into compliance.

  1. A novel approach to calculate thermal expansion of graphene: Molecular dynamics study

    NASA Astrophysics Data System (ADS)

    Ghasemi, Hamid; Rajabpour, Ali

    2017-05-01

    High surface-to-volume ratio is one of the extraordinary physical parameters of graphene which plays a crucial role in its electronic, thermal, mechanical and chemical behavior. Despite a lot of continuing theoretical and experimental researches, there are properties of graphene which are not fully understood and known. One of these properties is the thermal expansion coefficient (TEC) of graphene which shows a quite different behavior from what is expected for ordinary materials and has been reported to have a negative value for a wide range of temperatures. All previous researchers have calculated the TEC of graphene by considering its projected size which decreases when the temperature increases. In this paper, a novel method has been used to report the TEC of graphene based on the calculation of its real surface area using molecular dynamics simulations. Our results make clear how much the real surface area of graphene varies with respect to the temperature which is applicable in designing graphene-based nanodevices.

  2. Experimental study of expansion and compression effects on the stability of Taylor vortex flow

    NASA Astrophysics Data System (ADS)

    Mansour, M.; Ali, M. H.; Abd El-Maksoud, R. M.

    2016-08-01

    The aim of the present experimental work is to determine the stability limits of Taylor cells by expanding and compressing the cells. The investigation was performed under laminar flow condition with a wide gap between an inner rotating cylinder and outer stationary cylinder. In order to allow the expansion and compression of the cells, the test rig was designed with a sliding upper end plate and a fixed lower end plate. The objectives are to determine the maximum and minimum size limits of each number of cells as well as the stability margin of them. Since, unstable cells have various oscillations and time dependent structures which change the behavior of the flow; the investigations of the stability limits is quite necessary to avoid the possible generation of unstable cells. In addition, the results are used to detect the number of cells that can be generated in the gap at different fluid column lengths. A stability map, locating the stability state of all possible numbers of cells, is assigned in the results. The map provides overlap zones between stable cells, in which the operating conditions will always lead to stable cells, even if the number of cells is changed by changing the initial conditions. Moreover, a rare phenomenon was observed during the compression process when the cells jumps unusually from six to two cells without passing through the four-cell mode.

  3. Parametric study of combustion oscillation in a single-side expansion scramjet combustor

    NASA Astrophysics Data System (ADS)

    Ouyang, Hao; Liu, Weidong; Sun, Mingbo

    2016-10-01

    As a promising candidate for future air-breathing systems, the viability and efficiency of scramjet propulsion is challenged by a variety of factors including the combustion oscillation in scramjet combustor. A series of comparative experiments focusing on the combustion oscillation issue has been carried out in the present work. The obtained experimental results show that as the global equivalence ratio increases, the combustion oscillation becomes more regular and frequent which is the most intensive in the vicinity of the fuel jet and the periodic combustion oscillation is more possible when the injectors and flame-holding cavity are mounted on the expansion-side wall. In order to avoid the combustion oscillation in scramjet combustor, distributed injection scheme is an effective method which can induce two parts interacting stable flame. In addition, the results reveal that the varying fuel including hydrogen, ethylene and kerosene with different chemical kinetics has a significant effect on the reaction process in scramjet combustor, which can result in stable combustion, periodic oscillation and failed ignition respectively on the same operating condition of this paper. We believe that the present work is helpful to the designing of scramjet propulsion device.

  4. Mitochondrial footprints of human expansions in Africa.

    PubMed Central

    Watson, E; Forster, P; Richards, M; Bandelt, H J

    1997-01-01

    mtDNA studies support an African origin for modern Eurasians, but expansion events within Africa have not previously been investigated. We have therefore analyzed 407 mtDNA control-region sequences from 13 African ethnic groups. A number of sequences (13%) were highly divergent and coalesced on the "mitochondrial Eve" in Africans. The remaining sequences also ultimately coalesced on this sequence but fell into four major clusters whose starlike phylogenies testify to demographic expansions. The oldest of these African expansions dates to approximately 60,000-80,000 years ago. Eurasian sequences are derived from essentially one sequence within this ancient cluster, even though a diverse mitochondrial pool was present in Africa at the time. PMID:9326335

  5. Influencing Gameplay in Support of Early Synthetic Prototyping Studies

    DTIC Science & Technology

    2016-06-01

    this preliminary work can be used to support future studies on how to utilize scoring algorithms to support ESP research. 14. SUBJECT TERMS Early ...release; distribution is unlimited INFLUENCING GAMEPLAY IN SUPPORT OF EARLY SYNTHETIC PROTOTYPING STUDIES by Douglas J. Ross June 2016...DATE June 2016 3. REPORT TYPE AND DATES COVERED Master’s thesis 4. TITLE AND SUBTITLE INFLUENCING GAMEPLAY IN SUPPORT OF EARLY SYNTHETIC PROTOTYPING

  6. Are Time-Limited Grants Likely to Stimulate Sustained Growth in Primary Care Residency Training? A Study of the Primary Care Residency Expansion Program.

    PubMed

    Chen, Rossan Melissa; Petterson, Stephen; Bazemore, Andrew; Grumbach, Kevin

    2015-09-01

    To examine the perceived likelihood of sustaining new residency positions funded by five-year (2010-2015) Primary Care Residency Expansion (PCRE) grants from the Health Resources and Services Administration, which aimed to increase training output to address primary care workforce issues. During September-December 2013, the authors administered an online or telephone survey to program directors whose residency programs received PCRE grants. The main outcome measure was perceived likelihood of sustaining the expanded residency positions beyond the expiration of the grant, in the outlying years of 2016 and 2017 (when the positions will be partially supported) and after 2017 (when the positions will be unsupported). Of 78 eligible program directors, 62 responded (response rate = 79.5%). Twenty-eight (45.1%; 95% CI 32.9%-57.9%) reported that their programs were unlikely to, very unlikely to, or not planning to continue the expanded positions after the PCRE grant expires. Overall, 14 (22.5%) reported having secured full funding to support the expanded positions beyond 2017. Family medicine and pediatrics program directors were significantly less likely than internal medicine program directors to report having secured funding for the outlying years (P = .02). This study suggests that an approach to primary care residency training expansion that relies on time-limited grants is unlikely to produce sustainable growth of the primary care pipeline. Policy makers should instead implement systemic reform of graduate medical education (GME) financing and designate reliable sources of funding, such as Medicare and Medicaid GME funds, for new primary care residency positions.

  7. Laboratory Studies in Support of Planetary Science

    NASA Astrophysics Data System (ADS)

    Dalton, James B.; Castillo, J.; Hodyss, R.; Spilker, T.; Brown, L.; Orton, G.; Gudipati, M.; Mastrapa, R.; Atreya, S.; Nimmo, F.; Blankenship, D.; Durham, B.; Khurana, K.; others

    2009-09-01

    Scientific understanding in several fields within Planetary Science could enter a period of rapid progress and discovery once certain laboratory investigations are performed to provide valuable constraints on fundamental properties of radiation and matter, the physics and chemistry of atmospheric, surface and subsurface compounds, and dynamic interactions within the Solar System. Much theoretical work at present is based upon rough estimates of basic parameters that could be measured under carefully controlled laboratory conditions. Due to the exotic nature of many planetary environments, these investigations are unique, challenging, and generally expensive for the individual researchers. Traditionally, funding for laboratory work has lagged behind that of missions; at present, there is sufficient mission data already recorded to justify a sustained investment in laboratory activities over the coming decade that would result in an exponential return in scientific progress. Specific laboratory investigations are needed to provide fundamental physical, chemical, and biological parameters for theoretical models and observational interpretations that will drive the entire field of Planetary Science forward, particularly with regard to atmospheric dynamics, chemistry, and composition; celestial dynamics, surface chemistry and composition, planetary formation, geology, and geophysics; plasmas and magnetospheres; and applications of astrobiology and astrophysics for Solar System bodies. A series of topical white papers addressing each of these are being submitted to the Planetary Science Decadal Survey and highlighting the areas most in need of supporting laboratory work.

  8. Hanford personnel dosimeter supporting studies FY-1981

    SciTech Connect

    Not Available

    1982-08-01

    This report examined specific functional components of the routine external personnel dosimeter program at Hanford. Components studied included: dosimeter readout; dosimeter calibration; dosimeter field response; dose calibration algorithm; dosimeter design; and TLD chip acceptance procedures. Additional information is also presented regarding the dosimeter response to light- and medium-filtered x-rays, high energy photons and neutrons. This study was conducted to clarify certain data obtained during the FY-1980 studies.

  9. A computational study of two-phase viscoelastic systems in a capillary tube with a sudden contraction/expansion

    NASA Astrophysics Data System (ADS)

    Izbassarov, Daulet; Muradoglu, Metin

    2016-01-01

    Two-phase viscoelastic systems are computationally studied in a pressure-driven flow with a sudden contraction and expansion using a finite-difference/front-tracking method. The effects of viscoelasticity in drop and bulk fluids are investigated including high Weissenberg and Reynolds number cases up to Wi = 100 and Re = 100. The Finitely Extensible Non-linear Elastic-Chilcott and Rallison (FENE-CR) model is used to account for the fluid viscoelasticity. Extensive computations are performed to examine drop dynamics for a wide range of parameters. It is found that viscoelasticity interacts with drop interface in a non-monotonic and complicated way, and the two-phase viscoelastic systems exhibit very rich dynamics especially in the expansion region. At high Re, the drop undergoes large deformation in the contraction region followed by strong shape oscillations in the downstream of the expansion. For a highly viscous drop, a re-entrant cavity develops in the contraction region at the trailing edge which, in certain cases, grows and eventually causes encapsulation of ambient fluid. The re-entrant cavity formation is initiated at the entrance of the contraction and is highly influenced by the viscoelasticity. Compared to the corresponding straight channel case, the effects of viscoelasticity are reversed in the constricted channel: Viscoelasticity in drop/continuous phase hinders/enhances formation of the re-entrant cavity and entrainment of ambient fluid into main drop. Encapsulation of ambient fluid into main droplet may be another route to produce a compound droplet in microfluidic applications.

  10. Study of the causes and identification of the dominant mechanisms of failure of bellows expansion joints used in district heating system pipelines at MOEK

    NASA Astrophysics Data System (ADS)

    Tomarov, G. V.; Nikolaev, A. E.; Semenov, V. N.; Shipkov, A. A.; Shepelev, S. V.

    2015-06-01

    The results of laboratory studies of material properties and of numerical and analytical investigations to assess the stress-strain state of the metal of the bellows expansion joints used in the district heating system pipelines at MOEK subjected to corrosion failure are presented. The main causes and the dominant mechanisms of failure of the expansion joints have been identified. The influence of the initial crevice defects and the operating conditions on the features and intensity of destruction processes in expansion joints used in the district heating system pipelines at MOEK has been established.

  11. High Enthalpy Studies of Capsule Heating in an Expansion Tunnel Facility

    NASA Technical Reports Server (NTRS)

    Dufrene, Aaron; MacLean, Matthew; Holden, Michael

    2012-01-01

    Measurements were made on an Orion heat shield model to demonstrate the capability of the new LENS-XX expansion tunnel facility to make high quality measurements of heat transfer distributions at flow velocities from 3 km/s (h(sub 0) = 5 MJ/kg) to 8.4 km/s (h(sub 0) = 36 MJ/kg). Thirty-nine heat transfer gauges, including both thin-film and thermocouple instruments, as well as four pressure gauges, and high-speed Schlieren were used to assess the aerothermal environment on the capsule heat shield. Only results from laminar boundary layer runs are reported. A major finding of this test series is that the high enthalpy, low-density flows displayed surface heating behavior that is observed to be consistent with some finite-rate recombination process occurring on the surface of the model. It is too early to speculate on the nature of the mechanism, but the response of the gages on the surface seems generally repeatable and consistent for a range of conditions. This result is an important milestone in developing and proving a capability to make measurements in a ground test environment and extrapolate them to flight for conditions with extreme non-equilibrium effects. Additionally, no significant, isolated stagnation point augmentation ("bump") was observed in the tests in this facility. Cases at higher Reynolds number seemed to show the greatest amount of overall increase in heating on the windward side of the model, which may in part be due to small-scale particulate.

  12. Use of rapid prototyping drill template for the expansive open door laminoplasty: A cadaveric study.

    PubMed

    Rong, Xin; Wang, Beiyu; Chen, Hua; Ding, Chen; Deng, Yuxiao; Ma, Lipeng; Ma, Yanzhao; Liu, Hao

    2016-11-01

    Trough preparation is a technically demanding yet critical procedure for successful expansive open door laminoplasty (EOLP), requiring both proper position and appropriate bone removal. We aimed to use the specific rapid prototyping drill template to achieve such requirement. The 3D model of the cadaveric cervical spine was reconstructed using the Mimics 17.0 and Geomagic Studio 12.0 software. The drilling template was designed in the 3-Matic software. The trough position was simulated at the medial margin of the facet joint. Two holders were designed on both sides. On the open side, the holder would just allow the drill penetrate the ventral cortex of the lamina. On the hinge side, the holder was designed to keep the ventral cortex of the lamina intact. One orthopedic resident performed the surgery using the rapid prototyping drill template on four cadavers (template group). A control group of four cadavers were operated upon without the use of the template. The deviation of the final trough position from the simulated trough position was 0.18mm±0.51mm in the template group. All the troughs in the template group and 40% of the troughs in the control group were at the medial side of the facet joint. The complete hinge fracture rate was 5% in the template group, significantly lower than that (55%) in the control group (P=0.01). The rapid prototyping drill template could help the surgeon accomplish proper trough position and appropriate bone removal in EOLP on the cadaveric cervical spine. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Anisotropic Thermal Expansion of Zirconium Diboride: An Energy-Dispersive X-Ray Diffraction Study

    SciTech Connect

    Paxton, William A.; Özdemir, Tevfik E.; Şavklıyıldız, İlyas; Whalen, Terence; Biçer, Hülya; Akdoğan, Enver Koray; Zhong, Zhong; Tsakalakos, Thomas

    2016-01-01

    Zirconium diboride (ZrB2) is an attractive material due to its thermal and electrical properties. In recent years, ZrB2has been investigated as a superior replacement for sapphire when used as a substrate for gallium nitride devices. Like sapphire, ZrB2has an anisotropic hexagonal structure which defines its directionally dependent properties. However, the anisotropic behavior of ZrB2is not well understood. In this paper, we use energy-dispersive synchrotron X-ray diffraction to measure the thermal expansion of polycrystalline ZrB2powder from 300 to 1150 K. Nine Bragg reflections are fit using Pseudo-Voigt peak profiles and used to compute theaandclattice parameters using a nonlinear least-squares approximation. The temperature-dependent instantaneous thermal expansion coefficients are determined for eacha-axis andc-axis direction and are described by the following equations:αa= (4.1507×10-6+5.1086×10-9(T-293.15))/(1+4.1507×10-6(T-293.15
  14. Rapid palatal expansion effects on mandibular transverse dimensions in unilateral posterior crossbite patients: a three-dimensional digital imaging study.

    PubMed

    Ugolini, Alessandro; Doldo, Tiziana; Ghislanzoni, Luis T Huanca; Mapelli, Andrea; Giorgetti, Roberto; Sforza, Chiarella

    2016-01-01

    The purpose of this controlled study was to investigate indirect effects on mandibular arch dimensions, 1 year after rapid palatal expansion (RPE) therapy. Thirty-three patients in mixed dentition (mean age 8.8 years) showing unilateral posterior crossbite and maxillary deficiency were treated with a RPE (Haas type) cemented on the first permanent molars. Treatment protocol consisted of two turns per day until slight overcorrection of the molar transverse relationship occurred. The Haas expander was kept on the teeth as a passive retainer for an average of 6 months. Study models were taken prior (T1) and 15 months on average (T2) after expansion. A control group of 15 untreated subjects with maxillary deficiency (mean age 8.3 years) was also recorded with a 12-month interval. Stone casts were digitized with a 3D scanner (3Shape, DK). In the treated group, both mandibular intermolar distance (+1.9 mm) and mandibular molar angulation (+9°) increased. Mandibular incisor angulation showed an increase of 1.9°. There was little effect on intercanine distance and canine angulation. Controls showed a reduction in transverse arch dimension and a decrease in molar and canine angulation values. RPE protocol has indirect widening effects on the mandibular incisors and first molars.

  15. Application of Mythen detector: In-situ XRD study on the thermal expansion behavior of metal indium

    NASA Astrophysics Data System (ADS)

    Du, Rong; Chen, ZhongJun; Cai, Quan; Fu, JianLong; Gong, Yu; Wu, ZhongHua

    2016-07-01

    A Mythen detector has been equipped at the beamline 4B9A of Beijing Synchrotron Radiation Facility (BSRF), which is expected to enable BSRF to perform time-resolved measurement of X-ray diffraction (XRD) full-profiles. In this paper, the thermal expansion behavior of metal indium has been studied by using the in-situ XRD technique with the Mythen detector. The indium was heated from 303 to 433 K with a heating rate of 2 K/min. The in-situ XRD full-profiles were collected with a rate of one profile per 10 seconds. Rietveld refinement was used to extract the structural parameters. The results demonstrate that these collected quasi-real-time XRD profiles can be well used for structural analysis. The metal indium was found to have a nonlinear thermal expansion behavior from room temperature to the melting point (429.65 K). The a-axis of the tetragonal unit cell expands with a biquadratic dependency on temperature, while the c-axis contracts with a cubic dependency on temperature. By the time-resolved XRD measurements, it was observed that the [200] preferred orientation can maintain to about 403.15 K. While (110) is the last and detectable crystal plane just before melting of the polycrystalline indium foil. This study is not only beneficial to the application of metal indium, but also exhibits the capacity of in-situ time-resolved XRD measurements at the X-ray diffraction station of BSRF.

  16. Support needs of expectant mothers and fathers: a qualitative study.

    PubMed

    Widarsson, Margareta; Kerstis, Birgitta; Sundquist, Kristina; Engström, Gabriella; Sarkadi, Anna

    2012-01-01

    The aim of this study was to describe expectant mothers' and fathers' perceived needs of support during pregnancy. Twenty-two women and 10 men were interviewed in four focus groups and 13 individual interviews. Systematic text condensation was performed to analyze the data. Parents described not only a broad spectrum of social support needs but also needs of psychological and physical support. They also requested to share their experiences with others. The foci of care and parents' needs of support are more harmonized with medical support than with psychological and emotional support. Mothers' needs were predominately addressed in the health services, but fathers often felt "invisible." Antenatal services may need to offer more customized individual support and emphasize peer support in groups; the challenge is to involve both parents through communication and encouragement so they can support each other.

  17. Support Needs of Expectant Mothers and Fathers: A Qualitative Study

    PubMed Central

    Widarsson, Margareta; Kerstis, Birgitta; Sundquist, Kristina; Engström, Gabriella; Sarkadi, Anna

    2012-01-01

    The aim of this study was to describe expectant mothers’ and fathers’ perceived needs of support during pregnancy. Twenty-two women and 10 men were interviewed in four focus groups and 13 individual interviews. Systematic text condensation was performed to analyze the data. Parents described not only a broad spectrum of social support needs but also needs of psychological and physical support. They also requested to share their experiences with others. The foci of care and parents’ needs of support are more harmonized with medical support than with psychological and emotional support. Mothers’ needs were predominately addressed in the health services, but fathers often felt “invisible.” Antenatal services may need to offer more customized individual support and emphasize peer support in groups; the challenge is to involve both parents through communication and encouragement so they can support each other. PMID:23277729

  18. Accelerating the loop expansion

    SciTech Connect

    Ingermanson, R.

    1986-07-29

    This thesis introduces a new non-perturbative technique into quantum field theory. To illustrate the method, I analyze the much-studied phi/sup 4/ theory in two dimensions. As a prelude, I first show that the Hartree approximation is easy to obtain from the calculation of the one-loop effective potential by a simple modification of the propagator that does not affect the perturbative renormalization procedure. A further modification then susggests itself, which has the same nice property, and which automatically yields a convex effective potential. I then show that both of these modifications extend naturally to higher orders in the derivative expansion of the effective action and to higher orders in the loop-expansion. The net effect is to re-sum the perturbation series for the effective action as a systematic ''accelerated'' non-perturbative expansion. Each term in the accelerated expansion corresponds to an infinite number of terms in the original series. Each term can be computed explicitly, albeit numerically. Many numerical graphs of the various approximations to the first two terms in the derivative expansion are given. I discuss the reliability of the results and the problem of spontaneous symmetry-breaking, as well as some potential applications to more interesting field theories. 40 refs.

  19. Thermal Expansion

    NASA Astrophysics Data System (ADS)

    Ventura, Guglielmo; Perfetti, Mauro

    All solid materials, when cooled to low temperatures experience a change in physical dimensions which called "thermal contraction" and is typically lower than 1 % in volume in the 4-300 K temperature range. Although the effect is small, it can have a heavy impact on the design of cryogenic devices. The thermal contraction of different materials may vary by as much as an order of magnitude: since cryogenic devices are constructed at room temperature with a lot of different materials, one of the major concerns is the effect of the different thermal contraction and the resulting thermal stress that may occur when two dissimilar materials are bonded together. In this chapter, theory of thermal contraction is reported in Sect. 1.2 . Section 1.3 is devoted to the phenomenon of negative thermal expansion and its applications.

  20. Decision Support Systems: A Preliminary Study,

    DTIC Science & Technology

    1977-09-01

    goal for data management research is an integrated data system -12- _ _...__ _ _ ... ’ . ENGLISH LOGIC FORMAL DATA LISP OR SUBSET (KOWALSKI LANG FOR...studies are indicated to determine if cannonical forms can be used to make vector operations out of operations like COND (from LISP ). Studies of the...W.W., Boyer, Robert S., and Henneman , William H., (1972), "Computer Proofs of Limits Theorems", A.I. Jour., 3, pp. 27-60. 12. Bledsoe, W.W. and

    1. Maintenance therapy with histamine plus IL-2 induces a striking expansion of two CD56bright NK cell subpopulations in patients with acute myeloid leukemia and supports their activation

      PubMed Central

      Cerny-Reiterer, Sabine; Gleixner, Karoline V.; Stefanzl, Gabriele; Basilio, Jose; Herndlhofer, Susanne; Sperr, Wolfgang R.; Brons, Nicolaas H.C.; Casanova, Emilio; Zimmer, Jacques; Valent, Peter; Hofer, Erhard

      2016-01-01

      Histamine dihydrochloride (HDC) plus IL-2 has been proposed as a novel maintenance-immunotherapy in acute myeloid leukemia (AML). We analyzed the immunophenotype and function of natural killer (NK) cells in blood of AML patients treated after chemotherapy with HDC plus IL-2. The treatment caused a striking expansion of CD56brightCD16neg and CD56brightCD16low NK cell subpopulations. A reduced NK cell fraction recovered and high proportions of cells expressed the activating receptors NKG2D, NKp30, and NKp46. Concomitantly, KIR-expressing NK cells were reduced and NK cells with inhibitory NKG2A/CD94 receptors increased beyond normal levels. In addition, the immunotherapy-induced NK cells exhibited high capacity to produce IFN-γ and to degranulate. Furthermore, we provide evidence from subsequent in vitro studies that this is caused in part by direct effects of IL-2 on the CD56bright cells. IL-2 specifically induced proliferation of both CD56bright subpopulations, but not of CD56dim cells. It further preserved the expression of activating receptors and the capacity to produce IFN-γ and to degranulate. These data suggest that therapy with HDC plus IL-2 supports the reconstitution of a deficient NK cell fraction through the specific amplification of CD56bright NK cells giving rise to a functional NK cell compartment with high potential to combat leukemic disease. PMID:27341131

    2. Learning strategy refinement reverses early sensory cortical map expansion but not behavior: Support for a theory of directed cortical substrates of learning and memory.

      PubMed

      Elias, Gabriel A; Bieszczad, Kasia M; Weinberger, Norman M

      2015-12-01

      Primary sensory cortical fields develop highly specific associative representational plasticity, notably enlarged area of representation of reinforced signal stimuli within their topographic maps. However, overtraining subjects after they have solved an instrumental task can reduce or eliminate the expansion while the successful behavior remains. As the development of this plasticity depends on the learning strategy used to solve a task, we asked whether the loss of expansion is due to the strategy used during overtraining. Adult male rats were trained in a three-tone auditory discrimination task to bar-press to the CS+ for water reward and refrain from doing so during the CS- tones and silent intertrial intervals; errors were punished by a flashing light and time-out penalty. Groups acquired this task to a criterion within seven training sessions by relying on a strategy that was "bar-press from tone-onset-to-error signal" ("TOTE"). Three groups then received different levels of overtraining: Group ST, none; Group RT, one week; Group OT, three weeks. Post-training mapping of their primary auditory fields (A1) showed that Groups ST and RT had developed significantly expanded representational areas, specifically restricted to the frequency band of the CS+ tone. In contrast, the A1 of Group OT was no different from naïve controls. Analysis of learning strategy revealed this group had shifted strategy to a refinement of TOTE in which they self-terminated bar-presses before making an error ("iTOTE"). Across all animals, the greater the use of iTOTE, the smaller was the representation of the CS+ in A1. Thus, the loss of cortical expansion is attributable to a shift or refinement in strategy. This reversal of expansion was considered in light of a novel theoretical framework (CONCERTO) highlighting four basic principles of brain function that resolve anomalous findings and explaining why even a minor change in strategy would involve concomitant shifts of involved brain

    3. LEARNING STRATEGY REFINEMENT REVERSES EARLY SENSORY CORTICAL MAP EXPANSION BUT NOT BEHAVIOR: SUPPORT FOR A THEORY OF DIRECTED CORTICAL SUBSTRATES OF LEARNING AND MEMORY

      PubMed Central

      Elias, Gabriel A.; Bieszczad, Kasia M.; Weinberger, Norman M.

      2015-01-01

      Primary sensory cortical fields develop highly specific associative representational plasticity, notably enlarged area of representation of reinforced signal stimuli within their topographic maps. However, overtraining subjects after they have solved an instrumental task can reduce or eliminate the expansion while the successful behavior remains. As the development of this plasticity depends on the learning strategy used to solve a task, we asked whether the loss of expansion is due to the strategy used during overtraining. Adult male rats were trained in a three-tone auditory discrimination task to bar-press to the CS+ for water reward and refrain from doing so during the CS− tones and silent intertrial intervals; errors were punished by a flashing light and time-out penalty. Groups acquired this task to a criterion within seven training sessions by relying on a strategy that was “bar-press from tone-onset-to-error signal” (“TOTE”). Three groups then received different levels of overtraining: Group ST, none; Group RT, one week; Group OT, three weeks. Post-training mapping of their primary auditory fields (A1) showed that Groups ST and RT had developed significantly expanded representational areas, specifically restricted to the frequency band of the CS+ tone. In contrast, the A1 of Group OT was no different from naïve controls. Analysis of learning strategy revealed this group had shifted strategy to a refinement of TOTE in which they self-terminated bar-presses before making an error (“iTOTE”). Across all animals, the greater the use of iTOTE, the smaller was the representation of the CS+ in A1. Thus, the loss of cortical expansion is attributable to a shift or refinement in strategy. This reversal of expansion was considered in light of a novel theoretical framework (CONCERTO) highlighting four basic principles of brain function that resolve anomalous findings and explaining why even a minor change in strategy would involve concomitant shifts of

    4. Support for Teachers Studying Their Own Work.

      ERIC Educational Resources Information Center

      Evans, Claryce

      1991-01-01

      In fall 1984, the Educators' Forum was initiated to help stimulate and guide teachers studying their own practice. To assist each other with classroom investigations, the teachers hold a two-hour meeting, complete with a discussion leader. This article illustrates the process using sample topics involving cooperative science, first grade…

    5. RF Pre-Ionization to Create Faster, Hotter MHD-Driven Jets and Studies of Plasma Expansion Into a Vacuum

      NASA Astrophysics Data System (ADS)

      Chaplin, Vernon; Bellan, Paul

      2013-10-01

      We are studying MHD-driven jets relevant to astrophysical jets and fusion plasmas. Previous experiments at Caltech have focused on plasmas created by breaking down neutral gas using high voltage. The Paschen breakdown criterion governing this process sets an undesirable lower limit for the jet density. To overcome this constraint, we have developed a pre-ionization system powered by a pulsed, battery-powered, 3 kW 13.56 MHz RF amplifier. Pre-ionization of plasma in a tube behind the jet experiment's center electrode is expected to enable the formation of lower density, hotter, faster jets. Thus far, argon jets have been created with v >30 km/s, twice as fast as was previously achievable. The expansion of the RF plasma into the chamber prior to the discharge of the main capacitor bank involves surprisingly complex dynamics. There are two phases: initially plasma expansion along the background magnetic field is inhibited and the primary source of emission away from the RF antenna appears to be neutral atoms excited by fast electrons or photons from the RF source. At a later time, either before or after RF turn-off depending on the magnetic field configuration, a relatively high density (ne >1018 m-3) , cold (Te < 0.5 eV) cloud of plasma emerges from the source tube.

    6. Acoustical Studies of L-leucine and L-asparagine in aqueous electrolyte through thermal expansion coefficient

      NASA Astrophysics Data System (ADS)

      Jajodia, S.; Chimankar, O. P.; Kalambe, A.; Goswami, S. G.

      2012-12-01

      Amino acids are the building blocks of the proteins; their study provides important information, about the behaviour of larger biomolecules such as proteins. The properties of proteins such as their structure, solubility, denaturation, etc. are greatly influenced by electrolytes. Ultrasonic velocity and density values have been used for evaluation of thermal expansion coefficient and adiabatic compressibility for ternary systems (amino acid/salt + water) namely L-leucine / L-asparagine each in 1.5 M aqueous solution of NaCl used as solvent for various concentrations and at different temperatures (298.15K - 323.15K). Present paper reports the variation of various thermoacoustical parameters such as Moelwyn-Hughes parameter (C1), Beyer's non-linearity parameter (B/A), internal pressure (Pi), fractional free volume (f), available volume (Va), repulsive exponent (n), molecular constant (r), van der Waals' constant (b), Debye temperatue (θD), etc. have been computed from the thermal expansion coefficient with the change of concentration and temperature. The variations of all these parameters have been interpreted in terms of various intermolecular interactions such as strong, weak, charge transfer, complex formation, hydrogen bonding interaction. The structure making and breaking properties of the interacting components existing in proposed ternary systems. It shows the associating and dissociating tendency of the molecules of solute in solvent.The hetromolecular interactions are present in both the ternary systems.

    7. Drosophila melanogaster As a Model Organism to Study RNA Toxicity of Repeat Expansion-Associated Neurodegenerative and Neuromuscular Diseases

      PubMed Central

      Koon, Alex C.; Chan, Ho Yin Edwin

      2017-01-01

      For nearly a century, the fruit fly, Drosophila melanogaster, has proven to be a valuable tool in our understanding of fundamental biological processes, and has empowered our discoveries, particularly in the field of neuroscience. In recent years, Drosophila has emerged as a model organism for human neurodegenerative and neuromuscular disorders. In this review, we highlight a number of recent studies that utilized the Drosophila model to study repeat-expansion associated diseases (READs), such as polyglutamine diseases, fragile X-associated tremor/ataxia syndrome (FXTAS), myotonic dystrophy type 1 (DM1) and type 2 (DM2), and C9ORF72-associated amyotrophic lateral sclerosis/frontotemporal dementia (C9-ALS/FTD). Discoveries regarding the possible mechanisms of RNA toxicity will be focused here. These studies demonstrate Drosophila as an excellent in vivo model system that can reveal novel mechanistic insights into human disorders, providing the foundation for translational research and therapeutic development. PMID:28377694

    8. Population pharmacometrics in support of analgesics studies.

      PubMed

      Välitalo, P; Ranta, V-P; Hooker, A C; Kokki, M; Kokki, H

      2014-02-01

      Population pharmacometric modeling is used to explain both population trends as well as the sources and magnitude of variability in pharmacokinetic and pharmacodynamics data; the later, in part, by taking into account patient characteristics such as weight, age, renal function and genetics. The approach is best known for its ability to analyze sparse data, i.e. when only a few measurements have been collected from each subject, but other benefits include its flexibility and the potential to construct more detailed models than those used in the traditional individual curve fitting approach. This review presents the basic concepts of population pharmacokinetic and pharmacodynamic modeling and includes several analgesic drug examples. In addition, the use of these models to design and optimize future studies is discussed. In this context, finding the best design factors, such as the sampling times or the dose, for future studies within pre-defined criteria using a previously constructed population pharmacokinetic model can help researchers acquire clinically meaningful data without wasting resources and unnecessarily exposing vulnerable patient groups to study drugs and additional blood sampling. © 2014 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

    9. Microcarriers with Synthetic Hydrogel Surfaces for Stem Cell Expansion.

      PubMed

      Dias, Andrew D; Elicson, Jonathan M; Murphy, William L

      2017-08-01

      Microcarriers are scalable support surfaces for cell growth that enable high levels of expansion, and are particularly relevant for expansion of human mesenchymal stem cells (hMSCs). The goal of this study is to develop a poly(ethylene glycol) (PEG)-based microcarrier coating for hMSC expansion. Commercially available microcarriers do not offer customizability of microcarrier surface properties, including elastic modulus and surface cell adhesion ligands. The lab has previously demonstrated that tuning these material properties on PEG-based hydrogels can modulate important cellular growth characteristics, such as cell attachment and expansion, which are important in microcarrier-based culture. Eosin-Y is adsorbed to polystyrene microcarriers and used as a photoinitiator for thiol-ene polymerization under visible light. Resultant PEG coatings are over 100 µm thick and localized to microcarrier surfaces. This thickness is relevant for cells to react to mechanical properties of the hydrogel coating, and coated microcarriers support hMSC attachment and expansion. hMSC expansion is highly favorable on coated microcarriers in serum-free media, with doubling times under 25 h in the growth phase, and retained osteogenic and adipogenic differentiation capacity after culture on microcarriers. These microcarriers with defined, synthetic coatings enable tailorable surfaces for cell expansion that may be suitable for a variety of biomanufacturing applications. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

    10. Social support and work engagement: a study of Malaysian nurses.

      PubMed

      Othman, Noraini; Nasurdin, Aizzat Mohd

      2013-11-01

      This study addressed the question of whether social support (supervisor support and co-worker support) could contribute to the variance in work engagement. Nurses, as customer-contact employees, play an important role in representing the organization's competence. Their attitudes and behaviour toward patients has a significant influence on patients' satisfaction and perception of quality of service. The sample comprised 402 staff nurses working in three general hospitals in Peninsular Malaysia. Variables included demographic information, Utrecht Work Engagement Scale and Social Support Scale. Data analysis included descriptive statistics, correlations and regression analysis. Findings indicated that supervisor support was positively related to work engagement. Co-worker support was found to have no effect on work engagement. Supervisory support is an important predictor of work engagement for nurses. Nursing management should provide more training to nurse supervisors and develop nurse mentoring programmes to encourage more support to nurses. © 2012 John Wiley & Sons Ltd.

    11. Personal Commitment, Support and Progress in Doctoral Studies

      ERIC Educational Resources Information Center

      Martinsuo, Miia; Turkulainen, Virpi

      2011-01-01

      Earlier research on doctoral education has associated study progress with the student's own capabilities and faculty support. The purpose of this study is to investigate how students' personal commitment and various forms of support, as well as their complementary effects, explain progress in doctoral studies. Data were collected by a…

    12. Personal Commitment, Support and Progress in Doctoral Studies

      ERIC Educational Resources Information Center

      Martinsuo, Miia; Turkulainen, Virpi

      2011-01-01

      Earlier research on doctoral education has associated study progress with the student's own capabilities and faculty support. The purpose of this study is to investigate how students' personal commitment and various forms of support, as well as their complementary effects, explain progress in doctoral studies. Data were collected by a…

    13. Relativistic Sommerfeld Low Temperature Expansion

      NASA Astrophysics Data System (ADS)

      Lourenço, O.; Dutra, M.; Delfino, A.; Sá Martins, J. S.

      We derive a relativistic Sommerfeld expansion for thermodynamic quantities in many-body fermionic systems. The expansion is used to generate the equation of state of the Walecka model and its isotherms. We find that these results are in good agreement with numerical calculations, even when the expansion is truncated at its lowest order, in the low temperature regime, defined by T/xf ≪ 1. Although the interesting region near the liquid-gas phase transition is excluded by this criterion, the expansion may still find usefulness in the study of very cold nuclear matter systems, such as neutron stars.

    14. Health Blogging and Social Support: A 3-Year Panel Study.

      PubMed

      Keating, David M; Rains, Stephen A

      2015-01-01

      The reported study explored the implications of informal computer-mediated social support for the well-being of individuals coping with illness over the course of 3 years. A panel study was conducted in which respondents--bloggers writing about their experiences living with a health condition--reported on their perceptions of social support and well-being during 2010 and again during 2013. Among respondents who completed both questionnaires (n = 49), increases in support availability from family and friends were related to improvements in bloggers' health self-efficacy as well as improvements in bloggers' loneliness, particularly among those who also experienced increased support availability from blog readers. Increased blog reader support availability was associated with improvements in bloggers' health-related uncertainty. Among respondents who completed the initial questionnaire (N = 121), a survival analysis showed that neither support available from family and friends nor support from blog readers predicted continued health blogging over the 3-year period.

    15. A Computing Infrastructure for Supporting Climate Studies

      NASA Astrophysics Data System (ADS)

      Yang, C.; Bambacus, M.; Freeman, S. M.; Huang, Q.; Li, J.; Sun, M.; Xu, C.; Wojcik, G. S.; Cahalan, R. F.; NASA Climate @ Home Project Team

      2011-12-01

      Climate change is one of the major challenges facing us on the Earth planet in the 21st century. Scientists build many models to simulate the past and predict the climate change for the next decades or century. Most of the models are at a low resolution with some targeting high resolution in linkage to practical climate change preparedness. To calibrate and validate the models, millions of model runs are needed to find the best simulation and configuration. This paper introduces the NASA effort on Climate@Home project to build a supercomputer based-on advanced computing technologies, such as cloud computing, grid computing, and others. Climate@Home computing infrastructure includes several aspects: 1) a cloud computing platform is utilized to manage the potential spike access to the centralized components, such as grid computing server for dispatching and collecting models runs results; 2) a grid computing engine is developed based on MapReduce to dispatch models, model configuration, and collect simulation results and contributing statistics; 3) a portal serves as the entry point for the project to provide the management, sharing, and data exploration for end users; 4) scientists can access customized tools to configure model runs and visualize model results; 5) the public can access twitter and facebook to get the latest about the project. This paper will introduce the latest progress of the project and demonstrate the operational system during the AGU fall meeting. It will also discuss how this technology can become a trailblazer for other climate studies and relevant sciences. It will share how the challenges in computation and software integration were solved.

    16. Peer support for stroke survivors: a case study

      PubMed Central

      2014-01-01

      Background Innovative and sustainable programs are required to support the well-being of stroke survivors. Peer support is a potentially low cost way to enhance well-being of recent stroke survivors and the well-being and community reintegration of their peer supporters. This article describes the perceptions of stroke survivors, care partners, peer supporters, and professionals of an individual peer support program. Methods An instrumental case study design was used to examine a volunteer peer support program that provides acute care visits and telephone follow-up post-discharge. In particular, a) type of support provided, b) benefits for the stroke survivor and care partner, c) potential harms to the stroke survivor, d) impact of providing support on the peer supporter, and e) required processes were considered. Semi-structured interviews were carried out with 16 new stroke survivors and 8 care partners immediately following hospital discharge and then 6 months later, and with 7 peer supporters, 3 program co-ordinators and 4 health professionals to gather feedback from multiple stakeholders. Results Emotional, affirmational and informational support were perceived as being offered by the peer supporters. Peer visits were perceived as providing encouragement, motivation, validation, and decreased feelings of being alone. However, the visits were not perceived as beneficial to all stroke survivors. The impact on the peer supporters included increased social connections, personal growth, enjoyment, and feelings of making a difference in the lives of others. Involvement of the healthcare team, peer supporter training and a skilled coordinator were crucial to the success this program. Conclusions Peer support can potentially enhance service to stroke survivors and promote community reintegration for peer volunteers. Further research is needed to determine the preferred format and timing of peer support, and the characteristics of stroke survivors most likely to

    17. A human stromal-based serum-free culture system supports the ex vivo expansion/maintenance of bone marrow and cord blood hematopoietic stem/progenitor cells.

      PubMed

      da Silva, Cláudia Lobato; Gonçalves, Raquel; Crapnell, Kirsten B; Cabral, Joaquim M S; Zanjani, Esmail D; Almeida-Porada, Graça

      2005-07-01

      We investigated the role of human stromal layers (hu-ST) on the ex vivo expansion/maintenance of human hematopoietic stem/progenitor cells (HSC) from adult bone marrow (BM) and umbilical cord blood (CB). BM and CB CD34(+)-enriched cells were cultured in serum-free medium supplemented with SCF, bFGF, LIF, and Flt-3, in the presence or absence of stroma, and analyzed for proliferation, phenotype, and clonogenic potential. Significant expansion of BM and CB CD34(+) and CD34(+)CD38(-) cells were achieved in the presence of hu-ST. The differentiative potential of both BM and CB CD34(+)-enriched cells cocultured with hu-ST was primarily shifted toward the myeloid lineage, while maintaining/expanding a CD7(+) population. Clonogenic analysis of the expanded cells showed increases in progenitors of the myeloid lineage, including colony-forming unit-granulocyte, macrophage (CFU-GM) and colony-forming unit-granulocyte, erythroid, macrophage, megakaryocyte (CFU-Mix) for both BM (stroma and stroma-free conditions) and CB cells in the presence of stroma. These results indicate that adult hu-ST in the presence of appropriate cytokines can be used to efficiently expand/maintain myeloid and lymphoid cell populations from human BM and CB HSC.

    18. Classmate Peer-Coaching: "A Study Buddy Support Scheme"

      ERIC Educational Resources Information Center

      Thalluri, Jyothi; O'Flaherty, Jackie A.; Shepherd, Paul L.

      2014-01-01

      This study had two aims: firstly, to determine whether participation in a peer support scheme called Study Buddy Support (SBS) improves pass rates of "at risk" students, and secondly, to examine the advantages of this model over hierarchical models where senior students tutor junior years. Bachelor of Nursing and Midwifery students in a…

    19. Supporting Off-Shore Students: A Preliminary Study

      ERIC Educational Resources Information Center

      Hussin, Virginia

      2007-01-01

      This paper reports on the first part of a recent research study into current initiatives to support the learning of non-English speaking background (NESB) transnational students in Asia who are studying off-shore at Australian universities. Learning support and development staff in 12 universities were surveyed using a questionnaire. The survey…

    20. Studies on capillary tube expansion device used in J-T refrigerators operating with nitrogen-hydrocarbon mixtures

      NASA Astrophysics Data System (ADS)

      Harish Kruthiventi, S. S.; Venkatarathnam, G.

      2017-10-01

      Capillary tube expansion devices are used extensively in small closed cycle J-T refrigerators operating with refrigerant mixtures due to its low cost and the absence of any moving parts. It is possible for J-T refrigerators operating with mixtures that the velocity of refrigerant mixture at capillary tube outlet reaches a value where it equals the speed of sound at certain conditions. The variation of the speed of sound of nitrogen-hydrocarbon mixtures used in J-T refrigerators has been studied in two phase (vapour-liquid) and three-phase (Vapour-liquid-liquid) region as a function of temperature and pressure in this work. Also the conditions under which choking occurs in practical J-T refrigerators is investigated.

    1. On the relative importance of magnetospheric and ionospheric processes during substorm onset and expansion: A case study

      NASA Technical Reports Server (NTRS)

      Lopez, Ramon E.

      1992-01-01

      The question of whether substorm onset is triggered in the magnetotail or the ionosphere is presented. The possible influence of the ionosphere in the subsequent development of a substorm is discussed. Theoretical considerations involved are reviewed and a case study to address this question is examined. The evidence indicates that magnetotail processes initiate the sequence of events called a substorm, while the ionosphere appears to play a critical role in the subsequent evolution of the substorm expansion phase. However, the necessary observations, in particular high time resolution coordinated observations in the ionosphere and magnetotail are relatively rare. Continued examination of existing ground and space based data sets, in particular underutilized observations such as the Scatha data, may provide a more solid foundation for clarifying this issue and determining the relative importance of magnetospheric and ionospheric processes during substorms.

    2. On the relative importance of magnetospheric and ionospheric processes during substorm onset and expansion: A case study

      NASA Technical Reports Server (NTRS)

      Lopez, Ramon E.

      1992-01-01

      The question of whether substorm onset is triggered in the magnetotail or the ionosphere is presented. The possible influence of the ionosphere in the subsequent development of a substorm is discussed. Theoretical considerations involved are reviewed and a case study to address this question is examined. The evidence indicates that magnetotail processes initiate the sequence of events called a substorm, while the ionosphere appears to play a critical role in the subsequent evolution of the substorm expansion phase. However, the necessary observations, in particular high time resolution coordinated observations in the ionosphere and magnetotail are relatively rare. Continued examination of existing ground and space based data sets, in particular underutilized observations such as the Scatha data, may provide a more solid foundation for clarifying this issue and determining the relative importance of magnetospheric and ionospheric processes during substorms.

    3. [Social support assessment in Brazilian studies: conceptual aspects and measures].

      PubMed

      Gonçalves, Tonantzin Ribeiro; Pawlowski, Josiane; Bandeira, Denise Ruschel; Piccinini, Cesar Augusto

      2011-03-01

      This study investigated the different ways of evaluating the social support in Brazilian studies. A surveying of scientific Brazilian publications from 1987 to 2007 was done in the Indexpsi, Pepsic, SciELO and Lilacs databases according to keywords social support and social network. Fifty-five studies included some type of assessing social support in Brazilian samples. The results indicated a rise in the number of studies about social support assessment in the last years using interviews to investigate received and perceived support, predominantly. However, the construction was applied without theoretical basis and was associated with many other concepts, sometimes without an appropriate articulation. Besides, there were evidences of lacking reliable, valid and standardized instruments to Brazilian population by considering the instruments currently used and revised by this study.

    4. The C9ORF72 expansion sizes in patients with psychosis: a population-based study on the Northern Finland Birth Cohort 1966.

      PubMed

      Solje, Eino; Miettunen, Jouko; Marttila, Riikka; Helisalmi, Seppo; Laitinen, Marjo; Koivumaa-Honkanen, Heli; Isohanni, Matti; Hiltunen, Mikko; Jääskeläinen, Erika; Remes, Anne M

      2016-04-01

      Patients with behavioral variant frontotemporal dementia (bvFTD) have many psychotic symptoms, especially at the onset of the disease. The C9ORF72 expansion is the most common genetic etiology observed with bvFTD and the prevalence of the expansion is notably high among Finnish bvFTD patients. The aim of this study was to evaluate the prevalence of the C9ORF72 expansion among the clearly characterized patients with psychosis, mainly schizophrenia, in early midlife. The C9ORF72 repeat sizes were analyzed in 130 (48% women) patients with psychosis from the Northern Finland Birth Cohort 1966 (N=11,017), the mean onset age being 27.9 (SD 7.0) years. Despite the high frequency of psychiatric symptoms in bvFTD patients and the extremely high prevalence of the C9ORF72 expansion in Finland, pathogenic expansion (>40 repeats) was not detected among the Northern Finland Birth Cohort 1966 individuals with psychosis, indicating that these disorders, especially schizophrenia before the age of 43 years, may not be associated with the C9ORF72 expansion. However, we identified four cases with intermediate size repeats (17-26), but the role of the intermediate repeats in the etiology of psychosis is unknown.

    5. Ancient DNA from hunter-gatherer and farmer groups from Northern Spain supports a random dispersion model for the Neolithic expansion into Europe.

      PubMed

      Hervella, Montserrat; Izagirre, Neskuts; Alonso, Santos; Fregel, Rosa; Alonso, Antonio; Cabrera, Vicente M; de la Rúa, Concepción

      2012-01-01

      The phenomenon of Neolithisation refers to the transition of prehistoric populations from a hunter-gatherer to an agro-pastoralist lifestyle. Traditionally, the spread of an agro-pastoralist economy into Europe has been framed within a dichotomy based either on an acculturation phenomenon or on a demic diffusion. However, the nature and speed of this transition is a matter of continuing scientific debate in archaeology, anthropology, and human population genetics. In the present study, we have analyzed the mitochondrial DNA diversity in hunter-gatherers and first farmers from Northern Spain, in relation to the debate surrounding the phenomenon of Neolithisation in Europe. Analysis of mitochondrial DNA was carried out on 54 individuals from Upper Paleolithic and Early Neolithic, which were recovered from nine archaeological sites from Northern Spain (Basque Country, Navarre and Cantabria). In addition, to take all necessary precautions to avoid contamination, different authentication criteria were applied in this study, including: DNA quantification, cloning, duplication (51% of the samples) and replication of the results (43% of the samples) by two independent laboratories. Statistical and multivariate analyses of the mitochondrial variability suggest that the genetic influence of Neolithisation did not spread uniformly throughout Europe, producing heterogeneous genetic consequences in different geographical regions, rejecting the traditional models that explain the Neolithisation in Europe. The differences detected in the mitochondrial DNA lineages of Neolithic groups studied so far (including these ones of this study) suggest different genetic impact of Neolithic in Central Europe, Mediterranean Europe and the Cantabrian fringe. The genetic data obtained in this study provide support for a random dispersion model for Neolithic farmers. This random dispersion had a different impact on the various geographic regions, and thus contradicts the more simplistic total

    6. Ancient DNA from Hunter-Gatherer and Farmer Groups from Northern Spain Supports a Random Dispersion Model for the Neolithic Expansion into Europe

      PubMed Central

      Hervella, Montserrat; Izagirre, Neskuts; Alonso, Santos; Fregel, Rosa; Alonso, Antonio; Cabrera, Vicente M.; de la Rúa, Concepción

      2012-01-01

      Background/Principal Findings The phenomenon of Neolithisation refers to the transition of prehistoric populations from a hunter-gatherer to an agro-pastoralist lifestyle. Traditionally, the spread of an agro-pastoralist economy into Europe has been framed within a dichotomy based either on an acculturation phenomenon or on a demic diffusion. However, the nature and speed of this transition is a matter of continuing scientific debate in archaeology, anthropology, and human population genetics. In the present study, we have analyzed the mitochondrial DNA diversity in hunter-gatherers and first farmers from Northern Spain, in relation to the debate surrounding the phenomenon of Neolithisation in Europe. Methodology/Significance Analysis of mitochondrial DNA was carried out on 54 individuals from Upper Paleolithic and Early Neolithic, which were recovered from nine archaeological sites from Northern Spain (Basque Country, Navarre and Cantabria). In addition, to take all necessary precautions to avoid contamination, different authentication criteria were applied in this study, including: DNA quantification, cloning, duplication (51% of the samples) and replication of the results (43% of the samples) by two independent laboratories. Statistical and multivariate analyses of the mitochondrial variability suggest that the genetic influence of Neolithisation did not spread uniformly throughout Europe, producing heterogeneous genetic consequences in different geographical regions, rejecting the traditional models that explain the Neolithisation in Europe. Conclusion The differences detected in the mitochondrial DNA lineages of Neolithic groups studied so far (including these ones of this study) suggest different genetic impact of Neolithic in Central Europe, Mediterranean Europe and the Cantabrian fringe. The genetic data obtained in this study provide support for a random dispersion model for Neolithic farmers. This random dispersion had a different impact on the various

    7. A study of the variational aspects for the Fock expansion of the solution of hydrogenic atoms in constant magnetic fields

      NASA Astrophysics Data System (ADS)

      Sternberg, James Brian

      The study of hydrogen in a constant magnetic field has been one of the most persistent problems in non- relativistic quantum mechanics. Although it is conceptually one of the simplest problems that one can think of, the non-separability of the Schrödinger equation containing both a Coulombic term and a constant in magnetic term in the Hamiltonian has made the problem especially difficult. In this dissertation, we apply a solution in the form of the Fock expansion to this problem. It is shown that the logarithmic terms which are associated with the Fock expansion vanish. We then derive and solve a three term recurrence relation in order to find a set of solutions to this Schrödinger equation. Linear combinations of these Fock solutions which satisfy the physical boundary conditions are found, and at the same time upper bounds for the binding energies are found using the Raleigh-Ritz variational principal. It is shown that these same Fock solutions produce lower bounds for the binding energies when the Schwinger variational principal is employed. Therefore, the eigenenergies for bound states of hydrogen in a constant magnetic field can be bracketed from both above and below. We furthermore examine another recent method, that of Kravchenko, Liberman and Johansson[15] for solving the hydrogen atom in a constant magnetic field problem. We show that their method is equivalent to examining an eigenchannel in the R-matrix method of Bohm and Fano, and compare their results to the ones we obtain through variational methods on the Fock solution. We find that their method is both accurate and efficient for calculating the binding energies.

    8. A pilot study of distributed knowledge management and clinical decision support in the cloud.

      PubMed

      Dixon, Brian E; Simonaitis, Linas; Goldberg, Howard S; Paterno, Marilyn D; Schaeffer, Molly; Hongsermeier, Tonya; Wright, Adam; Middleton, Blackford

      2013-09-01

      Implement and perform pilot testing of web-based clinical decision support services using a novel framework for creating and managing clinical knowledge in a distributed fashion using the cloud. The pilot sought to (1) develop and test connectivity to an external clinical decision support (CDS) service, (2) assess the exchange of data to and knowledge from the external CDS service, and (3) capture lessons to guide expansion to more practice sites and users. The Clinical Decision Support Consortium created a repository of shared CDS knowledge for managing hypertension, diabetes, and coronary artery disease in a community cloud hosted by Partners HealthCare. A limited data set for primary care patients at a separate health system was securely transmitted to a CDS rules engine hosted in the cloud. Preventive care reminders triggered by the limited data set were returned for display to clinician end users for review and display. During a pilot study, we (1) monitored connectivity and system performance, (2) studied the exchange of data and decision support reminders between the two health systems, and (3) captured lessons. During the six month pilot study, there were 1339 patient encounters in which information was successfully exchanged. Preventive care reminders were displayed during 57% of patient visits, most often reminding physicians to monitor blood pressure for hypertensive patients (29%) and order eye exams for patients with diabetes (28%). Lessons learned were grouped into five themes: performance, governance, semantic interoperability, ongoing adjustments, and usability. Remote, asynchronous cloud-based decision support performed reasonably well, although issues concerning governance, semantic interoperability, and usability remain key challenges for successful adoption and use of cloud-based CDS that will require collaboration between biomedical informatics and computer science disciplines. Decision support in the cloud is feasible and may be a reasonable

    9. Nutrition support practice: a study of factors inherent in the delivery of nutrition support services.

      PubMed

      Agriesti-Johnson, C; Dwyer, K; Steinbaugh, M

      1988-01-01

      The purpose of this study was to determine the degree of intercorrelation among dietitian, physician, and team nutrition support functions. Eight hundred and eighty dietitians and physicians were asked to respond to a questionnaire describing nutrition support functions as reported in the literature and validated by a panel of nutrition support physicians and dietitians. Two hundred and fifty-four completed questionnaires were included in the study, 84 from physicians and 170 from dietitians. Intercorrelations among function statements were subjected to factor analysis. The magnitude and consistency of factor loadings suggest that nutrition support is not perceived as independent components, but as a comprehensive pattern or structure. However, there was one important difference in perception. The sample tended to have an "enteral" orientation to the dietitian role and a "parenteral" orientation to the physician and team roles. The data support the contention that all members of nutrition support teams need a common core of knowledge and a set of highly developed process skills which can best be attained through an integrated, rather than segmented, approach to team training.

    10. Amalgamation, Expansion, Quality Assurance and Innovations: A Case Study on a Key University in China

      ERIC Educational Resources Information Center

      Zhang, Jingning

      2010-01-01

      The Chinese higher education reform policies since 1993 have been pursued in a centralized, top-down manner, which some theorists characterize as "centralized decentralization" or governmental "steering at distance." This case-study dissertation has two purposes. First, is to evaluate the implementation or the "situated…

    11. Comparative Study of Student Support Services of AIOU and UKOU

      ERIC Educational Resources Information Center

      Choudhry, Amtul Hafeez; Gujjar, Aijaz Ahmed; Hafeez, Muhammad Rashid

      2008-01-01

      This paper attempts to compare the availability, quality, similarities and differences of student support services in Allama Iqbal Open University (AIOU) and United Kingdom Open University (UKOU) and also to identify and enlist the deficiencies that AIOU students are facing in the student support services. The study found out that student support…

    12. HREM study of structure of supported Pt catalysts

      NASA Astrophysics Data System (ADS)

      Yao, Ming-Hui; Smith, David J.; Kalakkad, Dinesh; Datye, Abhaya K.

      1993-03-01

      The surface structure and morphology of Pt catalysts supported on various oxides were studied by HREM profile imaging. An unstable Ti oxide overlayer and a stable crystalline monolayer on TiO2 supported Pt particles were observed after HTR at 923K. The overlayers could explain the SMSI in Pt/TiO2.

    13. Adult burn survivors' views of peer support: a qualitative study.

      PubMed

      Badger, Karen; Royse, David

      2010-01-01

      This qualitative study examined 30 burn survivors' perceptions of the value of peer support in their own psychosocial rehabilitation. Little research is available that investigates the role of peer support in post-burn recovery in terms of perceived benefits and costs. Findings revealed strong positive views regarding the helpfulness of peer support. Burn survivors reported that peer supporters provided a sense of belonging and affiliation and gave hope and confidence. Two-thirds of the sample had served as peer supporters themselves after receiving their injuries, suggesting that mutual aid does involve reaching out to others. At the same time, survivors spoke of possible costs in helping others. Involving peer supporters in the psychological rehabilitation of burn survivors may be an important complement to the medical team.

    14. Students with disabilities in higher education - perceptions of support needs and received support: a pilot study.

      PubMed

      Simmeborn Fleischer, Ann; Adolfsson, Margareta; Granlund, Mats

      2013-12-01

      Students with disabilities in higher education frequently need support to succeed in their studies. Perceived problems in managing studies and everyday life may be the same for students with different disabilities, although the reasons for support may vary between them. In this pilot study, a questionnaire aimed to survey everyday functioning in students with disabilities was tested. Thirty-four students with Asperger syndrome, motor disabilities or deafness/hearing impairments were asked 55 close-ended and open-ended questions on participation restrictions and available support programmes. One aim of this study was to test the usefulness of the questionnaire, and another aim was to identify students' perceptions of their everyday student life and the support they are offered, with a special focus on comparing perceptions of needs and support between students with Asperger syndrome and other student groups. The results indicate the need to plan recruitment of participants carefully and that the questionnaire was useful. The descriptive analyses indicated that the groups primarily reported the same difficulties; however, the open-ended comments indicated that the reasons for the problems vary between the groups. It indicates that Likert-type responses to questions concerning perceived difficulties need to be supplemented by open-ended questions on the perceived reasons to problems.

    15. Meta-evaluation of baseline studies of the Brazilian Family Health Strategy Expansion Project: a participatory and formative approach.

      PubMed

      Figueiró, Ana Cláudia; Hartz, Zulmira Maria de Araújo; Thuler, Luiz Claudio Santos; Dias, André Luiz Freitas

      2010-12-01

      A participatory, formative meta-evaluation of baseline studies in Brazil is presented. International standards recommended by associations of evaluators were used, along with "specificity" criteria built up using the terms of reference for proposals for the selection of studies. The methodological approach combined a "peer review" of baseline study reports, with a participatory (self) assessment for "primary" evaluators, the average of which provided the final score. Results revealed a classification of "good" and "very good" for the set of standards. The differences between the attribution of scores further highlight the importance of taking into account multiple points of view. Given the lack of pre-existing standards for the reports, the absence of standards and the incipient nature of evaluation focusing on utility, this meta-evaluation does not adequately reflect the quality or potential utility of the baseline studies, however, it will certainly contribute to overcoming these limitations and improving future impact studies of the Brazilian Family Health Strategy Expansion Project (PROESF).

    16. Learning nursing through simulation: A case study approach towards an expansive model of learning.

      PubMed

      Berragan, Liz

      2014-08-01

      This study explores the impact of simulation upon learning for undergraduate nursing students. The study objectives were (a) to explore the experiences of participating in simulation education for a small group of student nurses; and (b) to explore learning through simulation from the perspectives of the nursing students, the nurse educators and the nurse mentors. Conducted as a small-scale narrative case study, it tells the unique stories of a small number of undergraduate nursing students, nurse mentors and nurse educators and explores their experiences of learning through simulation. Data analysis through progressive focusing revealed that the nurse educators viewed simulation as a means of helping students to learn to be nurses, whilst, the nurse mentors suggested that simulation helped them to determine nursing potential. The students' narratives showed that they approached simulation learning in different ways resulting in a range of outcomes: those who were successfully becoming nurses, those who were struggling or working hard to become nurses and those who were not becoming nurses. Theories of professional practice learning and activity theory present an opportunity to articulate and theorise the learning inherent in simulation activities. They recognise the links between learning and the environment of work and highlight the possibilities for learning to inspire change and innovation.

    17. Study of the O(N) linear σ model at finite temperature using the 2PPI expansion

      NASA Astrophysics Data System (ADS)

      Verschelde, H.; de Pessemier, J.

      2002-01-01

      We show that a new expansion, which sums seagull and bubble graphs to all orders, can be applied to the O( N) linear σ-model at finite temperature. We prove that this expansion can be renormalized with the usual counterterms in a mass independent scheme and that Goldstone's theorem is satisfied at each order. At the one loop order of this expansion, the Hartree result for the effective potential (daisy and superdaisy graphs) is recovered. We show that at one loop 2PPI order, the self-energy of the σ-meson can be calculated exactly and that diagrams are summed beyond the Hartree approximation.

    18. A study of role expansion: a new GP role in cardiology care

      PubMed Central

      2014-01-01

      Background The National Health Service is reconfiguring health care services in order to meet the increasing challenge of providing care for people with long-term conditions and to reduce the demand on specialised outpatient hospital services by enhancing primary care. A review of cardiology referrals to specialised care and the literature on referral management inspired the development of a new GP role in Cardiology. This new extended role was developed to enable GPs to diagnose and manage patients with mild to moderate heart failure or atrial fibrillation and to use a range of diagnostics effectively in primary care. This entailed GPs participating in a four-session short course with on-going clinical supervision. The new role was piloted in a small number of GP practices in one county in England for four months. This study explores the impact of piloting the Extended Cardiology role on the GP’s role, patients’ experience, service delivery and quality. Methods A mixed methods approach was employed including semi-structured interviews with GPs, a patient experience survey, a quality review of case notes, and analysis on activity and referral data. Results The participating GPs perceived the extended GP role as a professional development opportunity that had the potential to reduce healthcare utilisation and costs, through a reduction in referrals, whilst meeting the patient’s wishes for the provision of care closer to home. Patient experience of the new GP service was positive. The standard of clinical practice was judged acceptable. There was a fall in referrals during the study period. Conclusion This new role in cardiology was broadly welcomed as a model of care by the participating GPs and by patients, because of the potential to improve the quality of care for patients in primary care and reduce costs. As this was a pilot study further development and continuing evaluation of the model is recommended. PMID:24885826

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

      SciTech Connect

      Ranjbar, Ben; Kennedy, Brendan J.

      2015-12-15

      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 transition 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.

    20. A study on thermal barrier coatings including thermal expansion mismatch and bond coat oxidation

      NASA Technical Reports Server (NTRS)

      Chang, George C.; Phucharoen, Woraphat; Miller, Robert A.

      1986-01-01

      The present investigation deals with a plasma-sprayed thermal barrier coating (TBC) intended for high temperature applications to advanced gas turbine blades. Typically, this type of coating system consists of a zirconia-yttria ceramic layer with a nickel-chromium-aluminum bond coat on a superalloy substrate. The problem on hand is a complex one due to the fact that bond coat oxidation and thermal mismatch occur in the TBC. Cracking in the TBC has also been experimentally illustrated. A clearer understanding of the mechanical behavior of the TBC is investigated. The stress states in a model thermal barrier coating as it cools down in air is studied. The powerful finite element method was utilized to model a coating cylindrical specimen. Four successively refined finite element models were developed. Some results obtained using the first two models have been reported previously. The major accomplishment is the successful development of an elastic TBC finite element model known as TBCG with interface geometry between the ceramic layer and the bond coat. An equally important milestone is the near-completion of the new elastic-plastic TBC finite element model called TBCGEP which yielded initial results. Representative results are presented.

    1. Controlling Thermal Expansion: A Metal-Organic Frameworks Route.

      PubMed

      Balestra, Salvador R G; Bueno-Perez, Rocio; Hamad, Said; Dubbeldam, David; Ruiz-Salvador, A Rabdel; Calero, Sofia

      2016-11-22

      Controlling thermal expansion is an important, not yet resolved, and challenging problem in materials research. A conceptual design is introduced here, for the first time, for the use of metal-organic frameworks (MOFs) as platforms for controlling thermal expansion devices that can operate in the negative, zero, and positive expansion regimes. A detailed computer simulation study, based on molecular dynamics, is presented to support the targeted application. MOF-5 has been selected as model material, along with three molecules of similar size and known differences in terms of the nature of host-guest interactions. It has been shown that adsorbate molecules can control, in a colligative way, the thermal expansion of the solid, so that changing the adsorbate molecules induces the solid to display positive, zero, or negative thermal expansion. We analyze in depth the distortion mechanisms, beyond the ligand metal junction, to cover the ligand distortions, and the energetic and entropic effect on the thermo-structural behavior. We provide an unprecedented atomistic insight on the effect of adsorbates on the thermal expansion of MOFs as a basic tool toward controlling the thermal expansion.

    2. Controlling Thermal Expansion: A Metal–Organic Frameworks Route

      PubMed Central

      2016-01-01

      Controlling thermal expansion is an important, not yet resolved, and challenging problem in materials research. A conceptual design is introduced here, for the first time, for the use of metal–organic frameworks (MOFs) as platforms for controlling thermal expansion devices that can operate in the negative, zero, and positive expansion regimes. A detailed computer simulation study, based on molecular dynamics, is presented to support the targeted application. MOF-5 has been selected as model material, along with three molecules of similar size and known differences in terms of the nature of host–guest interactions. It has been shown that adsorbate molecules can control, in a colligative way, the thermal expansion of the solid, so that changing the adsorbate molecules induces the solid to display positive, zero, or negative thermal expansion. We analyze in depth the distortion mechanisms, beyond the ligand metal junction, to cover the ligand distortions, and the energetic and entropic effect on the thermo-structural behavior. We provide an unprecedented atomistic insight on the effect of adsorbates on the thermal expansion of MOFs as a basic tool toward controlling the thermal expansion. PMID:28190918

    3. Standardised tobacco packaging: a health policy case study of corporate conflict expansion and adaptation

      PubMed Central

      Hatchard, Jenny L; Fooks, Gary J; Gilmore, Anna B

      2016-01-01

      Objectives To investigate opposition to standardised tobacco packaging in the UK. To increase understanding of how transnational corporations are adapting to changes in their access to policymakers precipitated by Article 5.3 of the Framework Convention on Tobacco Control (FCTC). Design Case study web-based documentary analysis, using NVivo V.10. Examination of relationships between opponents of standardised packaging and transnational tobacco companies (TTCs) and of the volume, nature, transparency and timing of their activities. Setting UK standardised packaging policy debate 2011–2013. Participants Organisations selected on basis of opposition to, or facilitation thereof, standardised tobacco packaging in the UK; 422 associated documents. Results Excluding tobacco manufacturing and packaging companies (n=12), 109 organisations were involved in opposing standardised packaging, 82 (75%) of which had a financial relationship with 1 or more TTC. These 82 organisations (43 actively opposing the measure, 39 facilitating opposition) were responsible for 60% of the 404 activities identified, including the majority of public communications and research production. TTCs were directly responsible for 28% of total activities, predominantly direct lobbying, but also financially underwrote third party research, communication, mass recruitment and lobbying. Active organisations rarely reported any financial relationship with TTCs when undertaking opposition activities. Conclusions The multifaceted opposition to standardised packaging was primarily undertaken by third parties with financial relationships with major tobacco manufacturers. Low levels of transparency regarding these links created a misleading impression of diverse and widespread opposition. Countries should strengthen implementation of Article 5.3 of the FCTC by systematically requiring conflict of interest declarations from all organisations participating in political or media debates on tobacco control. PMID

    4. Comprehensive Genome Scale Phylogenetic Study Provides New Insights on the Global Expansion of Chikungunya Virus.

      PubMed

      Chen, Rubing; Puri, Vinita; Fedorova, Nadia; Lin, David; Hari, Kumar L; Jain, Ravi; Rodas, Juan David; Das, Suman R; Shabman, Reed S; Weaver, Scott C

      2016-12-01

      outbreaks. These results provide a solid foundation for future evolutionary studies of CHIKV that can elucidate emergence mechanisms and also may help to predict future epidemics. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

    5. Standardised tobacco packaging: a health policy case study of corporate conflict expansion and adaptation.

      PubMed

      Hatchard, Jenny L; Fooks, Gary J; Gilmore, Anna B

      2016-10-07

      To investigate opposition to standardised tobacco packaging in the UK. To increase understanding of how transnational corporations are adapting to changes in their access to policymakers precipitated by Article 5.3 of the Framework Convention on Tobacco Control (FCTC). Case study web-based documentary analysis, using NVivo V.10. Examination of relationships between opponents of standardised packaging and transnational tobacco companies (TTCs) and of the volume, nature, transparency and timing of their activities. UK standardised packaging policy debate 2011-2013. Organisations selected on basis of opposition to, or facilitation thereof, standardised tobacco packaging in the UK; 422 associated documents. Excluding tobacco manufacturing and packaging companies (n=12), 109 organisations were involved in opposing standardised packaging, 82 (75%) of which had a financial relationship with 1 or more TTC. These 82 organisations (43 actively opposing the measure, 39 facilitating opposition) were responsible for 60% of the 404 activities identified, including the majority of public communications and research production. TTCs were directly responsible for 28% of total activities, predominantly direct lobbying, but also financially underwrote third party research, communication, mass recruitment and lobbying. Active organisations rarely reported any financial relationship with TTCs when undertaking opposition activities. The multifaceted opposition to standardised packaging was primarily undertaken by third parties with financial relationships with major tobacco manufacturers. Low levels of transparency regarding these links created a misleading impression of diverse and widespread opposition. Countries should strengthen implementation of Article 5.3 of the FCTC by systematically requiring conflict of interest declarations from all organisations participating in political or media debates on tobacco control. Published by the BMJ Publishing Group Limited. For permission to

    6. Vaccine stability study design and analysis to support product licensure.

      PubMed

      Schofield, Timothy L

      2009-11-01

      Stability evaluation supporting vaccine licensure includes studies of bulk intermediates as well as final container product. Long-term and accelerated studies are performed to support shelf life and to determine release limits for the vaccine. Vaccine shelf life is best determined utilizing a formal statistical evaluation outlined in the ICH guidelines, while minimum release is calculated to help assure adequate potency through handling and storage of the vaccine. In addition to supporting release potency determination, accelerated stability studies may be used to support a strategy to recalculate product expiry after an unintended temperature excursion such as a cold storage unit failure or mishandling during transport. Appropriate statistical evaluation of vaccine stability data promotes strategic stability study design, in order to reduce the uncertainty associated with the determination of the degradation rate, and the associated risk to the customer.

    7. Construction Land Expansion and Transfer of Gravity Center from 1984 to 2016 : A study on Beijing - Tianjin - Hebei Urban Agglomeration

      NASA Astrophysics Data System (ADS)

      Lv, Jinxia; Jiang, Weiguo

      2017-04-01

      With the economic development and technological innovation, urban planning and construction has already broken through the shackles of the natural conditions such as topography and geomorphology, and the social factors such as politics and location have been affected by the urbanization process in the process of urbanization. At the same time, the synergies between urban development and local economy, national policy, industrial distribution and so on are also paid more attention. As the third pole of Chinese economy after the Pearl River Delta and the Yangtze River Delta, the Beijing-Tianjin-Hebei Metropolis Circle has attracted extensive attention on experts and scholars in its urban development and location. In recent years, studies on urban development have not only analyzed the spatial characteristics of urban or urban agglomerations, but also discussed the relationship between urban development and certain elements or phenomena. This paper presents a multi-threshold and multi-feature extraction method for building land using the optical characteristics of different landforms, based on Landsat remote sensing images from 1984 to 2016. The method selected Automated Water Extraction Index (AWEI), Normalized Difference Vegetation Index (NDVI), Soil Extraction Index (SOEI) and Normalized Difference Built-up Index (BUEI) to extract the construction land. It is an example study area of Beijing to extract the construction land in 30 years and to do a examine research. Using the ArcGIS software to calculate, we can get the coordinates of the city center of gravity in Beijing in various years. It can be seen that the center of gravity of built-up area and the movement of the center of gravity in Beijing. The results showed that the construction land in Beijing has an increasing tendency in recent 30 years. The main characteristic of expansion is the way of high-speed outward development. From 1984 to 1999, the center of gravity of the city shifted to the northeast, and

    8. Specification aggregate quarry expansion: a case study demonstrating sustainable management of natural aggregate resources

      USGS Publications Warehouse

      Langer, William H.; Tucker, M.L.

      2003-01-01

      Many countries, provinces, territories, or states in the European Union, Australia, Canada, the United States, and elsewhere have begun implementing sustainability programs, but most of those programs stop short of sustainable management of aggregate resources. Sustainable practices do not always have to be conducted under the title of sustainability. This case study describes how Lafarge, a large multinational construction materials supplier, implemented the principles of sustainability even though there was an absence of existing local government policies or procedures addressing sustainable resource management. Jefferson County, Colorado, USA, is one of three counties in the six-county Denver, Colorado, region that has potentially available sources of crushed stone. Crushed stone comprises 30 percent of the aggregate produced in the area and plays a major role in regional aggregate resource needs. Jefferson County is home to four of the five crushed stone operations in the Denver region. Lafarge operates one of those four quarries. Lafarge recently proposed to expand its reserves by exchanging company-owned land for existing dedicated open space land adjacent to their quarry but owned by Jefferson County. A similar proposal submitted about 10 years earlier had been denied. Contrary to the earlier proposal, which was predicated on public relations, the new proposal was predicated on public trust. Although not explicitly managed under the moniker of sustainability, Lafarge used basic management principles that embody the tenets of sustainability. To achieve the goals of sustainable aggregate management where no governmental policies existed, Lafarge not only assumed their role of being a responsible corporate and environmental member of the community, but also assumed the role of facilitator to encourage and enable other stakeholders to responsibly resolve legitimate concerns regarding the Lafarge quarry proposal. Lafarge successfully presented an enlightened

    9. Media Naturalness Reduction and Compensatory Channel Expansion: A Study of Online and Face-to-Face Sections of the Same Course

      ERIC Educational Resources Information Center

      Kock, Ned; Garza, Vanessa

      2011-01-01

      This study provides a combined test of the media naturalness and channel expansion theories with a study of communication media perceptions and use outcomes in the context of a college information systems course delivery. Data was collected from undergraduate students at the middle and end of a long semester. Approximately half of the students…

    10. Nature of the Spin Liquid Ground State in a Breathing Kagome Compound Studied by NMR and Series Expansion

      NASA Astrophysics Data System (ADS)

      Orain, J.-C.; Bernu, B.; Mendels, P.; Clark, L.; Aidoudi, F. H.; Lightfoot, P.; Morris, R. E.; Bert, F.

      2017-06-01

      In the vanadium oxyfluoride compound (NH4 )2[C7H14 N ][V7O6 F18 ] (DQVOF), the V4 + (3 d1, S =1 /2 ) ions realize a unique, highly frustrated breathing kagome lattice composed of alternately sized, corner-sharing equilateral triangles. Here we present an O 17 NMR study of DQVOF, which isolates the local susceptibility of the breathing kagome network. By a fit to series expansion, we extract the ratio of the interactions within the breathing kagome plane, J∇/JΔ=0.55 (4 ) , and the mean antiferromagnetic interaction J ¯ =60 (7 ) K . Spin lattice (T1) measurements reveal an essentially gapless excitation spectrum with a maximum gap Δ /J ¯ =0.007 (7 ) . Our study provides new impetus for further theoretical investigations in order to establish whether the gapless spin liquid behavior displayed by DQVOF is intrinsic to its breathing kagome lattice or whether it is due to perturbations to this model, such as a residual coupling of the V4 + ions in the breathing kagome planes to the interlayer V3 + (S =1 ) spins.

    11. Interleukin-5 Supports the Expansion of Fas Ligand-Expressing Killer B Cells that Induce Antigen-Specific Apoptosis of CD4+ T Cells and Secrete Interleukin-10

      PubMed Central

      Klinker, Matthew W.; Reed, Tamra J.; Fox, David A.; Lundy, Steven K.

      2013-01-01

      Beyond their critical role in humoral immunity, B lymphocytes can employ a variety of immunomodulatory mechanisms including expression of the apoptosis-inducing molecule Fas ligand (FasL; CD178). Here, we extensively characterized the surface phenotype of FasL+ killer B cells, showing they are enriched in the IgMhighCD5+CD1dhigh B cell subset previously reported to contain a higher frequency of B cells producing interleukin-10 (IL-10). A rare population of B cells expressing IL-10 was present among FasL+ B cells, but most FasL+ B cells did not produce IL-10. We also identify interleukin-5 (IL-5) as a novel inducer of killer B cell function. Constitutively FasL+ B cells expressed higher levels of the IL-5 receptor, and treating B cells with IL-5 and CD40L resulted in the expansion of a B cell population enriched for FasL+ cells. B cells stimulated with IL-5 and CD40L were potent inducers of apoptosis in activated primary CD4+ T cells, and this killing function was antigen-specific and dependent upon FasL. IL-5 also enhanced IL-10 secretion in B cells stimulated with CD40L. Taken together these findings elucidate the relationship of FasL+ B cells and IL-10-producing B cells and demonstrate that IL-5 can induce or enhance both killer B cell activity and IL-10 secretion in B cells. Finally, we found that the killer B cell activity induced by IL-5 was completely blocked by IL-4, suggesting the existence of a previously unknown antagonistic relationship between these type-2 cytokines in modulating the activity of killer B cells. Targeting this IL-5/IL-4 signaling axis may therefore represent a novel area of drug discovery in inflammatory disorders. PMID:23940537

    12. Implementing the RISE second victim support programme at the Johns Hopkins Hospital: a case study

      PubMed Central

      Edrees, Hanan; Connors, Cheryl; Paine, Lori; Norvell, Matt; Taylor, Henry; Wu, Albert W

      2016-01-01

      Background Second victims are healthcare workers who experience emotional distress following patient adverse events. Studies indicate the need to develop organisational support programmes for these workers. The RISE (Resilience In Stressful Events) programme was developed at the Johns Hopkins Hospital to provide this support. Objective To describe the development of RISE and evaluate its initial feasibility and subsequent implementation. Programme phases included (1) developing the RISE programme, (2) recruiting and training peer responders, (3) pilot launch in the Department of Paediatrics and (4) hospital-wide implementation. Methods Mixed-methods study, including frequency counts of encounters, staff surveys and evaluations by RISE peer responders. Descriptive statistics were used to summarise demographic characteristics and proportions of responses to categorical, Likert and ordinal scales. Qualitative analysis and coding were used to analyse open-ended responses from questionnaires and focus groups. Results A baseline staff survey found that most staff had experienced an unanticipated adverse event, and most would prefer peer support. A total of 119 calls, involving ∼500 individuals, were received in the first 52 months. The majority of calls were from nurses, and very few were related to medical errors (4%). Peer responders reported that the encounters were successful in 88% of cases and 83.3% reported meeting the caller's needs. Low awareness of the programme was a barrier to hospital-wide expansion. However, over the 4 years, the rate of calls increased from ∼1–4 calls per month. The programme evolved to accommodate requests for group support. Conclusions Hospital staff identified the need for a multidisciplinary peer support programme for second victims. Peer responders reported success in responding to calls, the majority of which were for adverse events rather than for medical errors. The low initial volume of calls emphasises the importance of

    13. Theoretical study of negative thermal expansion in Y2Mo3O12: effect of water absorption

      NASA Astrophysics Data System (ADS)

      Sun, Qiang; Wu, Mingyi; Wang, Lei; Jia, Yu

      2013-03-01

      Y2Mo3O12 exhibits negative thermal expansion (NTE) in a large temperature range (473 ~ 1173 K). However, the material strongly absorb water and form a stable trihydrate structure, where the NTE disappears. Raman spectra revealed that some vibrational modes were missing in the hydrated structure. By DFT calculations, absorption of water in Y2Mo3O12 has been studied. Our results showed that water can strongly absorb in Y2Mo3O12 with O end of the water binding to Y cation, while one hydrogen approaches to the bridge O, which shared by polyhedrons YO6 and MoO4, and forms hydrogen bond. The absorption of water leads the angle of Y-O-Mo reduced, decreasing Y-Mo distance and consequently the volume of the material contracted. Calculated phonon spectra showed that the transverse vibration of Y-O-Mo is restricted due to water absorption. As a result, the NTE, originated from the vibrational mode, is hindered. Our MD simulations also revealed that water can easily diffuse and cross different channels in the material with the aid of Y cations.

    14. Evaluation of the effects of modified bonded rapid maxillary expansion on occlusal force distribution: A pilot study

      PubMed Central

      Uzuner, Fatma Deniz; Odabasi, Hande; Acar, Secil; Tortop, Tuba; Darendeliler, Nilufer

      2016-01-01

      Objective: To evaluate the effects of modified bonded rapid maxillary expansion (RME) on occlusal force distribution. Materials and Methods: The sample included 12 patients (7 girls and 5 boys; mean age: 13.1 years) at the permanent dentition stage with bilateral posterior cross-bite. The patients were treated with a modified bonded RME appliance, activated twice a day. The study was terminated when the palatal cusps of the maxillary posterior teeth were occluding with the buccal cusps of the mandibular posterior teeth. The postretention period was 3 months. The T-Scan III device was used to analyze the percentages of occlusal force distribution, and records were taken at the pretreatment (T1), the postreatment (T2), and the postretention (T3) periods. Wilcoxon signed rank test was used for statistical analyses. Results: Incisors were most frequently without contact, followed by canines. The highest forces were seen in the second and first molar regions. A significant decrease was seen in total occlusal force during treatment (T1–T2); however, during retention, the force returned to its initial value, and no significant differences were found (T1–T3). No differences were found between right and left sides and in occlusal forces of the teeth in all time periods. Conclusion: The use of modified bonded RME decreases the total occlusal forces during the treatment period, but it does returns to its initial value after the postretention period. PMID:27011748

    15. A polynomial chaos expansion based molecular dynamics study for probabilistic strength analysis of nano-twinned copper

      NASA Astrophysics Data System (ADS)

      Mahata, Avik; Mukhopadhyay, Tanmoy; Adhikari, Sondipon

      2016-03-01

      Nano-twinned structures are mechanically stronger, ductile and stable than its non-twinned form. We have investigated the effect of varying twin spacing and twin boundary width (TBW) on the yield strength of the nano-twinned copper in a probabilistic framework. An efficient surrogate modelling approach based on polynomial chaos expansion has been proposed for the analysis. Effectively utilising 15 sets of expensive molecular dynamics simulations, thousands of outputs have been obtained corresponding to different sets of twin spacing and twin width using virtual experiments based on the surrogates. One of the major outcomes of this work is that there exists an optimal combination of twin boundary spacing and twin width until which the strength can be increased and after that critical point the nanowires weaken. This study also reveals that the yield strength of nano-twinned copper is more sensitive to TBW than twin spacing. Such robust inferences have been possible to be drawn only because of applying the surrogate modelling approach, which makes it feasible to obtain results corresponding to 40 000 combinations of different twin boundary spacing and twin width in a computationally efficient framework.

    16. Reaction and spectroscopic study of supported metal oxide catalysts

      NASA Astrophysics Data System (ADS)

      Ramani, Narayanan C.

      The role of surface structure, cation reducibility, surface acidity and the effect of the support was examined in the reaction of 1-butene over well characterized, supported metal oxide catalysts. Cr, Mo and W oxides supported on SiOsb2 were used to study the effect of structure, surface acidity and cation reducibility in the isomerization and selective oxidation of 1-butene. Supported oxides of Mo on TiOsb2,\\ Alsb2Osb3 and SiOsb2 were used to understand the role of the support in the selective oxidation of 1-butene. The surface acidity of SiOsb2 supported Cr, Mo, W and V oxide catalysts was examined by pyridine adsorption. Existing theoretical models of acidity were compared against experimental data. Over Mo(VI)/SiOsb2 and W(VI)/SiOsb2, isomerization through both a Bronsted catalyzed pathway and an allylic pathway were observed, while only the allylic pathway was observed over Cr(VI)/SiOsb2. The greater reducibility of the Cr cation compared to Mo and W cations was identified as the reason for the allylic pathway being dominant over Cr(VI)/SiOsb2. Cation reducibility was again seen to play an important role in the selective oxidation of 1-butene over SiOsb2 supported metal oxides. The turn over frequencies for 1,3-butadiene formation followed the trend in red-ox ability, with Cr > Mo > W. The activity to 1,3-butadiene formation did not change with increasing weight loading of Mo over TiOsb2 and Alsb2Osb3 supports. An analysis of the turn over frequencies of the supports and the supported cations revealed that a support effect, through the bridging oxygen ligand, dominated the intrinsic cation reducibility of Mo for these catalysts. The existence of Bronsted acidity over SiOsb2 supported Cr, Mo and V oxides was shown by an analysis of the OH region of the infrared spectrum, and by the adsorption of 1-butene and pyridine. Existing theoretical models for Bronsted acidity over supported metal oxides were shown to be inadequate to describe the observed results over

    17. Spot sign on 90 second delayed CTA improves sensitivity for hematoma expansion and mortality: a prospective study

      PubMed Central

      Ciura, Viesha A.; Brouwers, H. Bart; Pizzolato, Raffaella; Ortiz, Claudia J.; Rosand, Jonathan; Goldstein, Joshua; Greenberg, Steven M.; Pomerantz, Stuart R; Gonzalez, R. Gilberto; Romero, Javier M.

      2014-01-01

      Background and Purpose The CTA spot sign is a validated biomarker for poor outcome and hematoma expansion in intracerebral hemorrhage (ICH). 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 ICH patients with the spot sign and increase the sensitivity of the spot sign. Methods We prospectively enrolled consecutive ICH patients undergoing first pass and 90 second delayed CTA over 18 months at a single academic center. Uni- and multivariate logistic regression were performed to assess clinical and neuroimaging covariates for relationship with hematoma expansion and mortality. Results 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 (OR) 17.7 (95% CI 3.7-84.2, p=0.0004), 8.3 (95% CI 2.0-33.4, p=0.004), and 12.0 (95% CI 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. Conclusions We demonstrate improved sensitivity for predicting hematoma expansion and poor outcome by adding a 90 second delayed CTA, which may enhance selection of patients that may benefit from hemostatic therapy. PMID:25300974

    18. Assessment of Multiple Outcomes: An Evaluation Research Study of a Compensatory Early Childhood Program (Child Parent Centers and Child Parent Expansion Program).

      ERIC Educational Resources Information Center

      Eash, Maurice J.; And Others

      Child Parent Centers (CPC) have been established in selected disadvantaged areas to provide systematic educational experiences for preschool children as young as three years of age. This study provides an update on the current state of the CPC and its latest adaption, the Child Parent Expansion (CPX) Program. A three-year, longitudinal evaluation…

    19. The Effect of Expansion of Vision Span on Reading Speed: A Case Study of EFL Major Students at King Khalid University

      ERIC Educational Resources Information Center

      Kana'an, Basim Hamdan Ibrahim; Rab, Salahud Din Abdul; Siddiqui, Ahlullah

      2014-01-01

      The objective of the study is to demonstrate how and to what extent the expansion of vision span could be a decisive factor in enhancing the reading speed of EFL major students in the English Department at King Khalid University while maintaining their previous level of comprehension. The reading speed of students in the English Department at KKU…

    20. EFFICIENT OPERATION AND ECONOMICAL EXPANSION OF UNDERGRADUATE TEACHING FACILITIES OF URBAN UNIVERSITIES. FINDINGS, CONCLUSIONS, AND RECOMMENDATIONS BASED ON A CASE STUDY OF DREXEL INSTITUTE OF TECHNOLOGY, PHILADELPHIA, PENNSYLVANIA.

      ERIC Educational Resources Information Center

      WOOD, FREDERIC D.

      INFORMATION CONCERNING EFFICIENT PLANT OPERATION AND ECONOMIC FACILITY EXPANSION TO BEST ACCOMMODATE INCREASED STUDENT ENROLLMENTS AT URBAN COLLEGES AND UNIVERSITIES WAS GENERATED FROM A CASE STUDY OF THE DREXEL INSTITUTE OF TECHNOLOGY. GENERAL AREAS INVESTIGATED WERE--(1) SPACE REQUIREMENTS WHICH WILL MEET ANTICIPATED INCREASES IN ENROLLMENT, (2)…

    1. Cancer support groups: a critical review of empirical studies.

      PubMed

      Gottlieb, Benjamin H; Wachala, Elizabeth D

      2007-05-01

      Support groups for adults affected by cancer are widely offered by local community and national agencies in North America. This type of psychosocial intervention is defined in terms of its structure and functions, and its theoretical underpinnings and models of practice are described. Forty-four empirical studies of professionally led cancer support groups are summarized and critically reviewed. These studies include 32 outcome evaluations of randomized controlled trials, two process evaluations, and 10 consumer satisfaction studies. The findings reveal high levels of consumer satisfaction, and the outcome evaluations substantiate the morale and other quality of life benefits short of prolonging life. Discussion centers on priorities for future research and practice.

    2. Micromechanics of expansive mechanisms in expansive cement concretes

      NASA Astrophysics Data System (ADS)

      Cohen, M. D.

      The kinetics of hydration were studied by monitoring the presence of various compounds by X-ray diffractometer, a chemical extraction method, and scanning electron microscope. These studies indicated that the rates of depletion of the expanding particles and sulfates are higher in the finer blends, which is why expansion stops earlier in these blends. It is shown that the double curvature phenomenon (strength-drop and sudden increase in the rate of expansion) is caused by mechanical failure (e.g., microcracking) of the matrix surrounding the expanding particles that are producing ettringite crystals. The theory of protective and partial protective coating is reviewed. A hypothesis is introduced which assumes that monosulfate is not formed immediately when ettringite stops forming but is preceded by an intermediate phase. Shrinkage studies show that expansive cements shrink more than portland cements. The results of these studies were used to develop a modified model of the expansive process. It was shown theoretically that the time of expansion is inversely proportional to the surface area of the expansive clinker and directly proportional to the amount of sulfate used.

    3. Changes in surgical team performance and safety climate attitudes following expansion of perioperative services: a repeated-measures study.

      PubMed

      Gillespie, Brigid M; Harbeck, Emma; Kang, Evelyn; Steel, Catherine; Fairweather, Nicole; Chaboyer, Wendy

      2017-08-10

      Objective The aim of the present study was to describe process changes in surgical team performance and team members' attitudes to safety culture following hospital relocation and expansion of perioperative services.Methods The study was a naturalistic study using structured observations and surveys to assess non-technical skills (NTS; i.e. communication, teamwork, situational awareness, decision making and leadership) in surgery. This interrupted time series design used mixed-linear regression models to examine the effect of phase (before and after hospital relocation) on surgical teams' NTS and their processes that may affect performance. Differences in self-reported teamwork and safety climate attitudes were also examined.Results In all, 186 procedures (100 before and 81 after hospital relocation) were observed across teams working in general, paediatric, orthopaedic and thoracic surgeries. Interobserver agreement ranged from 86% to 95%. An effect of phase was found, indicating that there were significant improvements after relocation in the use of NTS by the teams observed (P=0.020; 95% confidence interval 1.9-4.7).Conclusions The improvements seen in surgical teams' NTS performance and safety culture attitudes may be related to the move to a new state-of-the-art perioperative department.What is known about the topic? Patient safety in surgery relies on optimal team performance, underpinned by effective NTS.What does this paper add? The NTS of surgical teams may be improved through ergonomic innovations that promote teams' shared mental models.What are the implications for practitioners? Effective multidisciplinary teamwork relies on a combination of NTS and ergonomic factors, which inherently contribute to team performance and safety climate attitudes.

    4. Magnus expansion paradoxes in the study of equilibrium magnetization and entanglement in multi-pulse spin locking

      NASA Astrophysics Data System (ADS)

      Kuznetsova, E. I.; Fel'dman, E. B.; Feldman, D. E.

      2016-06-01

      Divergence of the Magnus expansion leads to paradoxes in the spin dynamics of solid-state NMR and in quantum informatics. This review presents results on quasi-equilibrium magnetization in a system of dipole-dipole (DD) coupled spins at times T_2\\ll t \\ll T1ρ in multiple-pulse spin locking ( T_2 is the transverse spin relaxation time and T1ρ is the rotating-frame spin-lattice relaxation time). It is shown how contradictions between the results obtained with the Magnus expansion and experimental data can be removed. Systems of two and three DD coupled spins in multi-pulse spin locking are considered, and the entanglement evolution is investigated using both the Magnus expansion and the exact solution. The critical temperature for an entangled state is also found.

    5. Phonon and thermal expansion properties in Weyl semimetals MX (M = Nb, Ta; X = P, As): ab initio studies.

      PubMed

      Chang, Dahu; Liu, Yaming; Rao, Fengfei; Wang, Fei; Sun, Qiang; Jia, Yu

      2016-06-07

      Weyl semimetal (WSM) is a new type of topological quantum material for future spintronic devices. Using the first-principles density functional theory, we systematically investigated the thermal expansion properties, and the temperature dependence of isovolume heat capacity and bulk modulus in WSMs MX (M = Nb, Ta; X = P, As). We also presented the phonon dispersion curves and its variation under stress in MX and the anisotropic thermal expansion properties due to the anisotropic crystal structure in WSMs have been predicted in our calculations. Intriguing, we found that the heat capacities increase more rapidly with increasing temperature in the low temperature region for all MX. Furthermore, our results showed that the thermal expansion properties are determined mainly by the isovolume heat capacity at low temperatures, while the bulk modulus has the major effect at high temperatures. These results are useful for applications of WSMs in electronic and spintronic devices.

    6. Atom cooling by nonadiabatic expansion

      SciTech Connect

      Chen Xi; Muga, J. G.; Campo, A. del; Ruschhaupt, A.

      2009-12-15

      Motivated by the recent discovery that a reflecting wall moving with a square-root-in-time trajectory behaves as a universal stopper of classical particles regardless of their initial velocities, we compare linear-in-time and square-root-in-time expansions of a box to achieve efficient atom cooling. For the quantum single-atom wave functions studied the square-root-in-time expansion presents important advantages: asymptotically it leads to zero average energy whereas any linear-in-time (constant box-wall velocity) expansion leaves a nonzero residual energy, except in the limit of an infinitely slow expansion. For finite final times and box lengths we set a number of bounds and cooling principles which again confirm the superior performance of the square-root-in-time expansion, even more clearly for increasing excitation of the initial state. Breakdown of adiabaticity is generally fatal for cooling with the linear expansion but not so with the square-root-in-time expansion.

    7. School Nurses' Support for Bereaved Students: A Pilot Study

      ERIC Educational Resources Information Center

      Lohan, Janet A.

      2006-01-01

      Children may have difficulty with schoolwork because of grief over the death of an important person in their lives. School nurses provide support to these children. This pilot study consisted of a Web-based survey completed by 6 school nurses in a 3-county area in Washington state. The purpose of this pilot study was to assess the need for…

    8. Third Culture Kids and College Support: A Case Study

      ERIC Educational Resources Information Center

      Holdren, Sarah Jennifer

      2013-01-01

      This single site case study applies the "Transition Cycle" framework (Pollock & Van Reken, 2009) to an institutionally-based, student-run support program for Third Culture Kids. The purpose of this study was to examine how Lewis and Clark College responded to the presence of Third Culture Kid, or Global Nomad, students on campus by…

    9. Supporting adolescents with type 1 diabetes mellitus: a qualitative study.

      PubMed

      Rostami, Shahnaz; Parsa-Yekta, Zohreh; Najafi Ghezeljeh, Tahereh; Vanaki, Zohreh

      2014-03-01

      Without sufficient support, type 1 diabetes mellitus often disturbs patients' normal lives. This study describes and explores the support that Iranian adolescents with type 1 diabetes mellitus experienced. Semistructured interviews were conducted with ten adolescents, seven family members, one dietitian, one nurse, and one school nurse. Participants were chosen using purposive sampling from two teaching hospitals and one high school in two urban areas of Iran. Using standard procedures for content analysis, three main themes were identified: maintaining a normal life; receiving tangible, informational, and emotional support from the family and society; and advancement of life toward normalization. The cornerstone of maintaining a normal life for adolescents with type 1 diabetes mellitus is to adopt an active role in taking care of themselves within their systems of support.

    10. Impact of the Affordable Care Act Medicaid expansion on emergency department high utilizers with ambulatory care sensitive conditions: A cross-sectional study.

      PubMed

      Gingold, Daniel B; Pierre-Mathieu, Rachelle; Cole, Brandon; Miller, Andrew C; Khaldun, Joneigh S

      2017-05-01

      The effect of the Affordable Care Act on emergency department (ED) high utilizers has not yet been thoroughly studied. We sought to determine the impact of changes in insurance eligibility following the 2014 Medicaid expansion on ED utilization for ambulatory care sensitive conditions (ACSC) by high ED utilizers in an urban safety net hospital. High utilizers were defined as patients with ≥4 visits in the 6months before their most recent visit in the study period (July-December before and after Maryland's Medicaid expansion in January 2014). A differences-in-differences approach using logistic regression was used to investigate if differences between high and low utilizer cohorts changed from before and after the expansion. During the study period, 726 (4.1%) out of 17,795 unique patients in 2013 and 380 (2.4%) of 16,458 during the same period in 2014 were high utilizers (p-value <0.001). ACSC-associated visit predicted being a high utilizer in 2013 (OR 1.66 (95% CI [1.37, 2.01])) and 2014 (OR 1.65 (95% CI [1.27, 2.15])) but this was not different between years (OR ratio 0.99, 95% CI [0.72, 1.38], p-value 0.97). Although the proportion of high utilizers decreased significantly after Maryland's Medicaid expansion, ACSC-associated ED visits by high ED utilizers were unaffected. Copyright © 2017 Elsevier Inc. All rights reserved.

    11. Caring together for elderly mothers: a qualitative study of relations between adult daughters and supportive home care workers.

      PubMed

      Keigher, S M; Bandstra, K L; Prater, S L

      1999-01-01

      This qualitative study examines relationships between adult daughters caring for elderly disabled mothers and the mothers' personal care workers (PCWs) paid directly by the Wisconsin Community Options Program (COP). A subset of a larger study, in these five cases PCWs provide substantial hands on care without substituting for the heavy care also provided by the daughters. Direct payment offers the daughters and workers freedom to schedule around their family obligations and other limits and tailor care to the abilities of all three participants. It also allows the daughter to be the paid provider when she chooses. Expansion of such supportive services could benefit many more low and middle income families.

    12. Support effects studied on model supported catalysts. Progress report, April 1, 1991--March 31, 1992

      SciTech Connect

      Gorte, R.G.

      1991-11-01

      We are studying model catalysts in which the active phase is deposited onto flat oxide substrates in order to understand how a catalyst is affected by its support. We have examined the following growth and stability of titania overlayers which had been vapor deposited onto a Rh foil; the growth of Pt films on ZnO(0001)Zn and O(0001)O and compared the results to those obtained for Pt on {alpha}-Al{sub 2}O{sub 3}(0001). Samples were prepared by vapor deposition of Pt onto flat substrates in ultra high vacuum, and metal coverages were measured using a quartz-crystal, film thickness monitor; the structure and CO adsorption properties of Pt films vapor deposited onto a ZrO{sub 2}(100) crystal; the deposition of Rh on a ZrO{sub 2}(100) crystal; The absorption of NO on Pt particles supported on CeO{sub 2}, {alpha}-Al{sub 2}O{sub 3}(0001), and the Zn- and O-polar surfaces of ZnO(0001). We have investigated supported oxides in order to understand the acidic properties that have been reported for monolayer oxides. Our first studies were of amorphous, silicalumina catalysts. Finally, we have also begun to prepare model supported oxides in order to be able to used spectroscopic methods to characterize the sites formed on these materials. Our first studies were of niobia deposition on oxidized Al films and on an {alpha}-Al{sub 2}O{sub 3}(0001) crystal.

    13. Examining Urban Expansion Using Multi-Temporal Landsat Imagery: a Case Study of the Montreal Census Metropolitan Area from 1975 TO 2015, Canada

      NASA Astrophysics Data System (ADS)

      Ma, Lingfei; Zhao, He; Li, Jonathan

      2016-06-01

      Urban expansion, particularly the movement of residential and commercial land use to sub-urban areas in metropolitan areas, has been considered as a significant signal of regional economic development. In 1970s, the economic centre of Canada moved from Montreal to Toronto. Since some previous research have been focused on the urbanization process in Greater Toronto Area (GTA), it is significant to conduct research in its counterpart. This study evaluates urban expansion process in Montréal census metropolitan area (CMA), Canada, between 1975 and 2015 using satellite images and socio-economic data. Spatial and temporal dynamic information of urbanization process was quantified using Landsat imagery, supervised classification algorithms and the post-classification change detection technique. Accuracy of the Landsat-derived land use classification map ranged from 80% to 97%. The results indicated that continuous growth of built-up areas in the CMA over the study period resulted in a decrease in the area of cultivated land and vegetation. The results showed that urban areas expanded 442 km2 both along major river systems and lakeshores, as well as expanded from urban centres to surrounded areas. The analysis revealed that urban expansion has been largely driven by population growth and economic development. Consequently, the urban expansion maps produced in this research can assist decision-makers to promote sustainable urban development, and forecast potential changes in urbanization growth patterns.

    14. Thermal stability and thermal expansion studies of cubic fluorite-type MgF{sub 2} up to 135 GPa

      SciTech Connect

      Sun, X.W.; Song, T.; Wei, X.P.; Quan, W.L.; Liu, X.B.; Su, W.F.

      2014-04-01

      Highlights: • The thermal expansion of MgF{sub 2} with a fluorite-type structure has been investigated. • The quasi-harmonic Debye model is applied to take into account the thermal effect. • Particular attention is paid to the prediction of thermal expansion for the first time. - Abstract: The thermal expansion of MgF{sub 2} with a fluorite structure has been investigated at high pressures using plane-wave pseudopotential scheme within the local density approximation correction in the frame of density functional theory based on the analysis of thermal stability using classical molecular dynamics simulations up to 6500 K. To investigate the thermodynamic properties like as the P–V–T equation of state and volumetric thermal expansion coefficient α{sub V} of cubic fluorite-type MgF{sub 2} at extended pressure and temperature ranges, we apply the quasi-harmonic Debye model in which the phononic effects are considered. The P–V relationship and α{sub V} dependence of the pressure up to 135 GPa at different temperatures, and the V–T relationship and α{sub V} dependence of the temperature up to the melting temperature 1500 K at different pressures have been obtained.

    15. The Global Expansion of Children's Television: A Case Study of the Adaptation of "Sesame Street" in Spain

      ERIC Educational Resources Information Center

      Moran, Kristin C.

      2006-01-01

      The landscape of children's programming is changing because of the increased exportation of children's television programs created in the USA. Networks have been aggressively marketing programs to an international audience through individual program sales and satellite network expansion. Some see problems as a result of the potential shift in…

    16. The Global Expansion of Children's Television: A Case Study of the Adaptation of "Sesame Street" in Spain

      ERIC Educational Resources Information Center

      Moran, Kristin C.

      2006-01-01

      The landscape of children's programming is changing because of the increased exportation of children's television programs created in the USA. Networks have been aggressively marketing programs to an international audience through individual program sales and satellite network expansion. Some see problems as a result of the potential shift in…

    17. Polymerization shrinkage and hygroscopic expansion of contemporary posterior resin-based filling materials--a comparative study.

      PubMed

      Rüttermann, Stefan; Krüger, Sören; Raab, Wolfgang H-M; Janda, Ralf

      2007-10-01

      To investigate the polymerization shrinkage and hygroscopic expansion of contemporary posterior resin-based filling materials. The densities of SureFil (SU), CeramXMono (CM), Clearfil AP-X (CF), Solitaire 2 (SO), TetricEvoCeram (TE), and Filtek P60 (FT) were measured using the Archimedes' principle prior to and 15min after curing for 20, 40 and 60s and after 1h, 24h, 7 d, and 30 d storage at 37 degrees C in water. Volumetric changes (DeltaV) in percent after polymerization and after each storage period in water were calculated from the changes of densities. Water sorption and solubility were determined after 30 d for all specimens and their curing times. Two-way ANOVA was calculated for shrinkage and repeated measures ANOVA was calculated for hygroscopic expansion (p<0.05). DeltaV depended on filler load but not on curing time (SU approximately -2.0%, CM approximately -2.6%, CF approximately -2.1%, SO approximately -3.3%, TE approximately -1.7%, FT approximately -1.8%). Hygroscopic expansion depended on water sorption and solubility. Except for SU, all materials showed DeltaV approximately +1% after water storage. Polymerization shrinkage depended on the type of resin-based filling material but not on curing time. Shrinkage was not compensated by hygroscopic expansion.

    18. An experimental study of the pulsed outflow of a dense plasma into a submerged medium - Axisymmetric expansion regimes

      NASA Astrophysics Data System (ADS)

      Aleksandrov, A. F.; Timofeev, I. B.; Iusupaliev, U.

      1991-02-01

      Pulsed outflow of a dense plasma into a submerged medium was investigated experimentally in the case where plasma expansion is determined completely by gasdynamic processes. Based on experimental data, a dimensionless parameter is proposed which determines the regime of plasma outflow. The effects of the plasmatron nozzle diameter, specific energy input into the discharge, and medium gas pressure are discussed.

    19. Forecasting deforestation and carbon emissions in tropical developing countries facing demographic expansion: a case study in Madagascar.

      PubMed

      Vieilledent, Ghislain; Grinand, Clovis; Vaudry, Romuald

      2013-06-01

      Anthropogenic deforestation in tropical countries is responsible for a significant part of global carbon dioxide emissions in the atmosphere. To plan efficient climate change mitigation programs (such as REDD+, Reducing Emissions from Deforestation and forest Degradation), reliable forecasts of deforestation and carbon dioxide emissions are necessary. Although population density has been recognized as a key factor in tropical deforestation, current methods of prediction do not allow the population explosion that is occurring in many tropical developing countries to be taken into account. Here, we propose an innovative approach using novel computational and statistical tools, including R/GRASS scripts and the new phcfM R package, to model the intensity and location of deforestation including the effect of population density. We used the model to forecast anthropogenic deforestation and carbon dioxide emissions in five large study areas in the humid and spiny-dry forests of Madagascar. Using our approach, we were able to demonstrate that the current rapid population growth in Madagascar (+3.39% per year) will significantly increase the intensity of deforestation by 2030 (up to +1.17% per year in densely populated areas). We estimated the carbon dioxide emissions associated with the loss of aboveground biomass to be of 2.24 and 0.26 tons per hectare and per year in the humid and spiny-dry forest, respectively. Our models showed better predictive ability than previous deforestation models (the figure of merit ranged from 10 to 23). We recommend this approach to reduce the uncertainty associated with deforestation forecasts. We also underline the risk of an increase in the speed of deforestation in the short term in tropical developing countries undergoing rapid population expansion.

    20. Forecasting deforestation and carbon emissions in tropical developing countries facing demographic expansion: a case study in Madagascar

      PubMed Central

      Vieilledent, Ghislain; Grinand, Clovis; Vaudry, Romuald

      2013-01-01

      Anthropogenic deforestation in tropical countries is responsible for a significant part of global carbon dioxide emissions in the atmosphere. To plan efficient climate change mitigation programs (such as REDD+, Reducing Emissions from Deforestation and forest Degradation), reliable forecasts of deforestation and carbon dioxide emissions are necessary. Although population density has been recognized as a key factor in tropical deforestation, current methods of prediction do not allow the population explosion that is occurring in many tropical developing countries to be taken into account. Here, we propose an innovative approach using novel computational and statistical tools, including R/GRASS scripts and the new phcfM R package, to model the intensity and location of deforestation including the effect of population density. We used the model to forecast anthropogenic deforestation and carbon dioxide emissions in five large study areas in the humid and spiny-dry forests of Madagascar. Using our approach, we were able to demonstrate that the current rapid population growth in Madagascar (+3.39% per year) will significantly increase the intensity of deforestation by 2030 (up to +1.17% per year in densely populated areas). We estimated the carbon dioxide emissions associated with the loss of aboveground biomass to be of 2.24 and 0.26 tons per hectare and per year in the humid and spiny-dry forest, respectively. Our models showed better predictive ability than previous deforestation models (the figure of merit ranged from 10 to 23). We recommend this approach to reduce the uncertainty associated with deforestation forecasts. We also underline the risk of an increase in the speed of deforestation in the short term in tropical developing countries undergoing rapid population expansion. PMID:23789079

    1. Multicomponent plasma expansion into vacuum with non-Maxwellian electrons

      NASA Astrophysics Data System (ADS)

      Elkamash, Ibrahem; Kourakis, Ioannis

      2016-10-01

      The expansion of a collisionless plasma into vacuum has been widely studied since the early works of Gurevich et al and Allen and coworkers. It has received momentum in recent years, in particular in the context of ultraintense laser pulse interaction with a solid target, in an effort to elucidate the generation of high energy ion beams. In most present day experiments, laser produced plasmas contain several ion species, due to increasingly complicated composite targets. Anderson et al have studied the isothermal expansion of a two-ion-species plasma. As in most earlier works, the electrons were assumed to be isothermal throughout the expansion. However, in more realistic situations, the evolution of laser produced plasmas into vacuum is mainly governed by nonthermal electrons. These electrons are characterized by particle distribution functions with high energy tails, which may significantly deviate from the Maxwellian distribution. In this paper, we present a theoretical model for plasma expansion of two component plasma with nonthermal electrons, modelled by a kappa-type distribution. The superthermal effect on the ion density, velocity and the electric field is investigated. It is shown that energetic electrons have a significant effecton the expansion dynamics of the plasma. This work was supported from CPP/QUB funding. One of us (I.S. Elkamash) acknowledges financial support by an Egyptian Government fellowship.

    2. 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.

    3. Supporting Argumentation through Students' Questions: Case Studies in Science Classrooms

      ERIC Educational Resources Information Center

      Chin, Christine; Osborne, Jonathan

      2010-01-01

      This study explores how student-generated questions can support argumentation in science. Students were asked to discuss which of two graphs showing the change in temperature with time when ice is heated to steam was correct. Four classes of students, aged 12-14 years, from two countries, first wrote questions about the phenomenon. Then, working…

    4. Characteristics of Teachers' Support on Learning: A Case Study

      ERIC Educational Resources Information Center

      Sardà, Anna; Márquez, Conxita; Sanmartí, Neus

      2014-01-01

      One of the problems in science education research is obtaining evidence that particular teacher support of learning helps achieve better academic results for students. Classroom ecology involves many variables that are difficult to control and, moreover, many results can only be seen in the medium term. The purpose of this case study on an expert…

    5. Design study for a magnetically supported reaction wheel

      NASA Technical Reports Server (NTRS)

      Stocking, G.; Dendy, J.; Sabnis, A.

      1974-01-01

      Results are described of a study program in which the characteristics of a magnetically supported reaction wheel are defined. Tradeoff analyses are presented for the principal components, which are then combined in several reaction wheel design concepts. A preliminary layout of the preferred configuration is presented along with calculated design and performance parameters. Recommendations are made for a prototype development program.

    6. Using Technology to Support Teachers' Lesson Modifications during Lesson Study

      ERIC Educational Resources Information Center

      Skultety, Lisa; Gonzalez, Gloriana; Vargas, Gabriela

      2017-01-01

      Lesson study is a professional development activity that increases teachers' attention to student thinking. However, coordinating teachers' live observations of a lesson can be challenging. Using the framework of "distributed cognition," we investigate whether technology supports teachers' examination of student thinking and aids the…

    7. Supporting Argumentation through Students' Questions: Case Studies in Science Classrooms

      ERIC Educational Resources Information Center

      Chin, Christine; Osborne, Jonathan

      2010-01-01

      This study explores how student-generated questions can support argumentation in science. Students were asked to discuss which of two graphs showing the change in temperature with time when ice is heated to steam was correct. Four classes of students, aged 12-14 years, from two countries, first wrote questions about the phenomenon. Then, working…

    8. A Formal Model for the Study of Communication Support Systems.

      ERIC Educational Resources Information Center

      Holsapple, Clyde W.; And Others

      1996-01-01

      Documents the lack of conceptual frameworks for integrating research on organizational computer-based communications technologies. Formalizes an integrated model for studying computer communication support phenomena in organizations using a knowledge management perspective and set-theoretic notation. Defines two types of communications support…

    9. Exploration of Infertile Couples’ Support Requirements: A Qualitative Study

      PubMed Central

      Jafarzadeh-Kenarsari, Fatemeh; Ghahiri, Ataollah; Habibi, Mojtaba; Zargham-Boroujeni, Ali

      2015-01-01

      Background Due to high prevalence of infertility, increasing demand for infertility treatment, and provision of high quality of fertility care, it is necessary for healthcare professionals to explore infertile couples’ expectations and needs. Identification of these needs can be a prerequisite to plan the effective supportive interventions. The current study was, therefore, conducted in an attempt to explore and to understand infertile couples’ experiences and needs. Materials and Methods This is a qualitative study based on a content analysis ap- proach. The participants included 26 infertile couples (17 men and 26 women) and 7 members of medical personnel (3 gynecologists and 4 midwives) as the key informants. The infertile couples were selected from patients attending public and private infertility treatment centers and private offices of infertility specialists in Isfahan and Rasht, Iran, during 2012-2013. They were selected through purposive sampling method with maximum variation. In-depth unstructured interviews and field notes were used for data gathering among infertile couples. The data from medical personnel was collected through semi-structured interviews. The interview data were analyzed using conventional content analysis method. Results Data analysis revealed four main categories of infertile couples’ needs, including: i. Infertility and social support, ii. Infertility and financial support, iii. Infertility and spiritual support and iv. Infertility and informational support. The main theme of all these categories was assistance and support. Conclusion The study showed that in addition to treatment and medical needs, infertile couples encounter various challenges in different emotional, psychosocial, communicative, cognitive, spiritual, and economic aspects that can affect various areas of their life and lead to new concerns, problems, and demands. Thus, addressing infertile couples’ needs and expectations alongside their medical treatments as

    10. Project Orion, Environmental Control and Life Support System Integrated Studies

      NASA Technical Reports Server (NTRS)

      Russell, James F.; Lewis, John F.

      2008-01-01

      Orion is the next vehicle for human space travel. Humans will be sustained in space by the Orion subystem, environmental control and life support (ECLS). The ECLS concept at the subsystem level is outlined by function and technology. In the past two years, the interface definition with other subsystems has increased through different integrated studies. The paper presents the key requirements and discusses three recent studies (e.g., unpressurized cargo) along with the respective impacts on the ECLS design moving forward.

    11. Understanding spatial-temporal urban expansion pattern (1990-2009) using impervious surface data and landscape indexes: a case study in Guangzhou (China)

      NASA Astrophysics Data System (ADS)

      Fan, Fenglei; Fan, Wei

      2014-01-01

      A new viewpoint for understanding the urban expansion using impervious surface information, which is obtained using remote sensing imagery is presented. The purpose of this study is to understand and describe the urban expansion pattern with the view of impervious surfaces instead of the conventional view of land use/land cover. Six years' worth of impervious surface data (1990-2009) of Guangzhou are extracted via linear spectral unmixing analysis methods and spatial and temporal characteristics are discussed in detail. The area, density, and gravity centers changes of the impervious surfaces are analyzed to explain internal/external urban expansion. Meanwhile, five landscape indexes, such as patch density, edge density, mean patch size, area-weighted, and fragmentation index, are utilized to describe landscape changes of Guangzhou in past 20 years, which are influenced deeply by the impervious surface expansion. In order to detail landscape changes, two transects corresponding to the two urban expansion directions are designed and five landscape metrics in these two transects are reported. Conclusions can be drawn and shown as following: (1) temporally, the area of impervious surfaces increases from 12,998 to 59,911 ha from 1990 to 2009. The amount of impervious surface varies in different periods. The annual growth rates of impervious surface area during 1990-1995, 1995-1998, and 1998-2000 are 10.16%, 11.61%, and 10.78%, respectively; (2) annual growth rates decrease from 10.78% (1998-2000) to 5.67% (2000-2003). Nevertheless, from 2003-2009, the annual growth rate has a slight increase compared to a former period. The rate is 5.91% (3) spatially, gravity centers of medium and high percentage impervious surfaces migrate slightly; and (4) according to the gradient analysis in the two transects, it can be observed that the high percentage of impervious surface increases gradually in new city districts (from west to east and from south to north).

    12. Anisotropic lattice thermal expansion of PbFeBO{sub 4}: A study by X-ray and neutron diffraction, Raman spectroscopy and DFT calculations

      SciTech Connect

      Murshed, M. Mangir; Mendive, Cecilia B.; Curti, Mariano; Nénert, Gwilherm; Kalita, Patricia E.; Lipinska, Kris; Cornelius, Andrew L.; Huq, Ashfia; Gesing, Thorsten M.

      2014-11-15

      Highlights: • Mullite-type PbFeBO{sub 4} shows uni-axial negative coefficient of thermal expansion. • Anisotropic thermal expansion of the metric parameters was modeled using modified Grüneisen approximation. • The model includes harmonic, quasi-harmonic and intrinsic anharmonic contributions to the internal energy. • DFT calculation, temperature- and pressure-dependent Raman spectra help understand the phonon decay and associated anharmonicity. - Abstract: The lattice thermal expansion of mullite-type PbFeBO{sub 4} is presented in this study. The thermal expansion coefficients of the metric parameters were obtained from composite data collected from temperature-dependent neutron and X-ray powder diffraction between 10 K and 700 K. The volume thermal expansion was modeled using extended Grüneisen first-order approximation to the zero-pressure equation of state. The additive frame of the model includes harmonic, quasi-harmonic and intrinsic anharmonic potentials to describe the change of the internal energy as a function of temperature. The unit-cell volume at zero-pressure and 0 K was optimized during the DFT simulations. Harmonic frequencies of the optical Raman modes at the Γ-point of the Brillouin zone at 0 K were also calculated by DFT, which help to assign and crosscheck the experimental frequencies. The low-temperature Raman spectra showed significant anomaly in the antiferromagnetic regions, leading to softening or hardening of some phonons. Selected modes were analyzed using a modified Klemens model. The shift of the frequencies and the broadening of the line-widths helped to understand the anharmonic vibrational behaviors of the PbO{sub 4}, FeO{sub 6} and BO{sub 3} polyhedra as a function of temperature.

    13. Expansion of the Scan Endgame Program for Aircraft Survivability Studies and Development of a Supporting User’s Guide.

      DTIC Science & Technology

      1982-12-01

      programs would be handled auto - matically, requiring minimal computer experience by the user and eliminating the problem of bothersome typing errors. The...8217 LUJW L) * Z* 0 V) e o t .-u u’(X z -~ *.CtW* 000000000I.- H + CLW Lu C* w LUo xJ) * * LuJO * 000c0cc0.ooco/ 1)Z .Q4 Lu 0 LU- N-* *I-4j* (3(3(33(3(3( 0 LU

    14. A convergence study for the Laguerre expansion in the moment equation method for neoclassical transport in general toroidal plasmas

      SciTech Connect

      Nishimura, S.; Sugama, H.; Maassberg, H.; Beidler, C. D.; Murakami, S.; Nakamura, Y.; Hirooka, S.

      2010-08-15

      The dependence of neoclassical parallel flow calculations on the maximum order of Laguerre polynomial expansions is investigated in a magnetic configuration of the Large Helical Device [S. Murakami, A. Wakasa, H. Maassberg, et al., Nucl. Fusion 42, L19 (2002)] using the monoenergetic coefficient database obtained by an international collaboration. On the basis of a previous generalization (the so-called Sugama-Nishimura method [H. Sugama and S. Nishimura, Phys. Plasmas 15, 042502 (2008)]) to an arbitrary order of the expansion, the 13 M, 21 M, and 29 M approximations are compared. In a previous comparison, only the ion distribution function in the banana collisionality regime of single-ion-species plasmas in tokamak configurations was investigated. In this paper, the dependence of the problems including electrons and impurities in the general collisionality regime in an actual nonsymmetric toroidal configuration is reported. In particular, qualities of approximations for the electron distribution function are investigated in detail.

    15. A multisatellite case study of the expansion of a substorm current wedge in the near-earth magnetotail

      NASA Technical Reports Server (NTRS)

      Lopez, R. E.; Lui, A. T. Y.

      1990-01-01

      Results are presented on observations from four satellites (GOES 5, GOES 6, AMPTE CCE, and AMPTE IRM) and two ground stations (San Juan and Tucson) on a substorm that occurred on April 19, 1985 at about 0830 UT. The four spacecraft were arrayed in a configuration that made it possible to separate the effects arising from the longitudinal versus the radial expansion of the substorm current wedge and thus to examine its spatial evolution. The sequence of events that was observed suggests that, during this substorm, the disruption of the cross-tail current sheet, the formation of the substorm current wedge, and the expansion of the plasma sheet began in the near-earth region, and subsequently spread tailward as well as longitudinally.

    16. Fundamental studies of supported bimetallic catalysts by NMR spectroscopy

      SciTech Connect

      Savargaonkar, Nilesh

      1996-10-17

      Various hydrogenation reactions on transition metals are important commercially whereas certain hydrogenolysis reactions are useful from fundamental point of view. Understanding the hydrogen mobility and kinetics of adsorption-desorption of hydrogen is important in understanding the mechanisms of such reactions involving hydrogen. The kinetics of hydrogen chemisorption was studied by means of selective excitation NMR on silica supported Pt, Rh and Pt-Rh catalysts. The activation energy of hydrogen desorption was found to be lower on silica supported Pt catalysts as compared to Rh and Pt-Rh catalysts. It was found that the rates of hydrogen adsorption and desorption on Pt-Rh catalyst were similar to those on Rh catalyst and much higher as compared to Pt catalyst. The Ru-Ag bimetallic system is much simpler to study than the Pt-Rh system and serves as a model system to characterize more complicated systems such as the K/Ru system. Ag was found to decrease the amounts of adsorbed hydrogen and the hydrogen-to-ruthenium stoichiometry. Ag reduced the populations of states with low and intermediate binding energies of hydrogen on silica supported Ru catalyst. The rates of hydrogen adsorption and desorption were also lower on silica supported Ru-Ag catalyst as compared to Ru catalyst. This report contains introductory information, the literature review, general conclusions, and four appendices. An additional four chapters and one appendix have been processed separately for inclusion on the data base.

    17. Supported lipid bilayers as models for studying membrane domains.

      PubMed

      Kiessling, Volker; Yang, Sung-Tae; Tamm, Lukas K

      2015-01-01

      Supported lipid bilayers have been in use for over 30 years. They have been employed to study the structure, composition, and dynamics of lipid bilayer phases, the binding and distribution of soluble, integral, and lipidated proteins in membranes, membrane fusion, and interactions of membranes with elements of the cytoskeleton. This review focuses on the unique ability of supported lipid bilayers to study liquid-ordered and liquid-disordered domains in membranes. We highlight methods to produce asymmetric lipid bilayers with lipid compositions that mimic those of the extracellular and cytoplasmic leaflets of cell membranes and the functional reconstitution of membrane proteins into such systems. Questions related to interleaflet domain coupling and membrane protein activation have been addressed and answered using advanced reconstitution and imaging procedures in symmetric and asymmetric supported membranes with and without coexisting lipid phase domains. Previously controversial topics regarding anomalous and anisotropic diffusion in membranes have been resolved by using supported membrane approaches showing that the propensity of certain lipid compositions to form "rafts" are important but overlaid with "picket-fence" interactions that are imposed by a subtended cytoskeletal network.

    18. The origin of early age expansions induced in cementitious materials containing shrinkage reducing admixtures

      SciTech Connect

      Sant, Gaurav; Lothenbach, Barbara; Juilland, Patrick; Le Saout, Gwenn; Weiss, Jason; Scrivener, Karen

      2011-03-15

      Studies on the early-age shrinkage behavior of cement pastes, mortars, and concretes containing shrinkage reducing admixtures (SRAs) have indicated these mixtures frequently exhibit an expansion shortly after setting. While the magnitude of the expansion has been noted to be a function of the chemistry of the cement and the admixture dosage; the cause of the expansion is not clearly understood. This investigation uses measurements of autogenous deformation, X-ray diffraction, pore solution analysis, thermogravimetry, and scanning electron microscopy to study the early-age properties and describe the mechanism of the expansion in OPC pastes made with and without SRA. The composition of the pore solution indicates that the presence of the SRA increases the portlandite oversaturation level in solution which can result in higher crystallization stresses which could lead to an expansion. This observation is supported by deformation calculations for the systems examined.

    19. Administrative support of novice science teachers: A multiple case study

      NASA Astrophysics Data System (ADS)

      Iacuone, Leann

      Novice science teachers leave the confines of colleges and universities to embark on a new adventure in education where they aim to influence young minds, make a difference in the world, and share their love for their content. They have learned their pedagogical skills with the support and assistance of fellow classmates, a supporting professor, and a cooperating teacher. These teachers enter their new place of employment and are met with many unexpected challenges, such as a lack of resources, no one to ask questions of, and a busy staff with already established relationships, causing them to feel an overall lack of support and resulting in many new teachers rethinking their career choice and leaving the field of education within 5 years of entering. This multiple-case study investigated the administrative support 4 novice science teachers received during an academic year and the novice teachers' perceptions of the support they received to answer the following research question: How do novice science teachers who have consistent interactions with administrators develop during their first year? To answer this question, semistructured interviews, reflection journals, observations, resumes, long-range plans, and student discipline referrals were collected. The findings from this study show novice science teachers who had incidents occur in the classroom requiring administrative assistance and guidance felt more confident in enforcing their classroom management policies and procedures as the year progressed to change student behavior. The novice science teachers perceived administrators who provided resources including technology, office supplies, science supplies, and the guidance of a mentor as supportive. Novice science teachers who engaged in dialogue after administrative observations, were provided the opportunity to attend professional development outside the district, and had a mentor who taught the same discipline made more changes to their instructional

    20. Interprofessional Intervention to Support Mature Women: A Case Study.

      PubMed

      Pechacek, Judith M; Drake, Diana; Terrell, Carrie Ann; Torkelson, Carolyn

      2015-01-01

      Understanding the impact interprofessional teamwork has on patient outcomes is of great interest to health care providers, educators, and administrators. This article describes one clinical team, Women's Health Specialists, and their implementation of an interprofessional health intervention course: "Mindfulness and Well-being: The Mature Woman" (MW: MW) to support mature women's health needs in midlife (age 40-70 years) and empower patient involvement in self-care. The provider team works to understand how their interprofessional education and collaborative practice (IPECP) interventions focused on supporting midlife women are associated with improved quality and clinical outcomes. This case study describes the work of the Women's Health Specialists clinic in partnership with the National Center for Interprofessional Education and Collaborative Practice to study the impact an interprofessional team has on the health needs of women in midlife. This article summarizes the project structure, processes, outputs, and outcomes. Data collection, analysis, strategy, and next steps for future midlife women's projects are also discussed.

    1. Geotechnical support and topical studies for nuclear waste geologic repositories

      SciTech Connect

      Not Available

      1989-01-01

      The present report lists the technical reviews and comments made during the fiscal year 1988 and summarizes the technical progress of the topical studies. In the area of technical assistance, there were numerous activities detailed in the next section. These included 24 geotechnical support activities, including reviews of 6 Study Plans (SP) and participation in 6 SP Review Workshops, review of one whole document Site Characterization Plan (SCP) and participation in the Assembled Document SCP Review Workshops by 6 LBL reviewers; the hosting of a DOE program review, the rewriting of the project statement of work, 2 trips to technical and planning meetings; preparation of proposed work statements for two new topics for DOE, and 5 instances of technical assistance to DOE. These activities are described in a Table in the following section entitled Geoscience Technical Support for Nuclear Waste Geologic Repositories.''

    2. Support needs of informal hospice caregivers: a qualitative study.

      PubMed

      Kutner, Jean; Kilbourn, Kristin M; Costenaro, Allison; Lee, Courtney A; Nowels, Carolyn; Vancura, Jenny L; Anderson, Derek; Keech, Tarah Ellis

      2009-12-01

      Informal caregivers of hospice patients experience multiple stressors that can negatively impact physical, psychological, and emotional health. The goal of this qualitative study was to understand caregivers' needs to inform the feasibility, structure, and content of a telephone-based counseling intervention. Focus groups and interviews with 36 former hospice caregivers and 11 hospice staff from 6 hospices were conducted. Interviews and focus groups were audio-recorded, transcribed, and analyzed using a constant comparative approach. Key content areas included coping, emotional support, self-care, logistical issues, and bereavement. Respondents supported telephone-based counseling, appreciating its relative anonymity and convenience. It was recommended that calls be initiated by the counselor, on a weekly basis, and that one counselor be assigned to each caregiver. Hospice staff emphasized the need to coordinate telephone counseling with hospice care, scheduling around and communicating with hospice staff. Most caregivers indicated that they would participate in telephone-based counseling were it available; hospice staff thought that half of caregivers would participate. A pervasive theme was that "there can never be enough support for a caregiver." Informal caregivers of hospice patients have support needs that are amenable to telephone-based counseling designed to be complementary to existing hospice services. Based on these qualitative findings, we are pilot-testing a telephone-based cognitive-behavioral stress management program for informal caregivers of hospice patients.

    3. Providing Field Support for the Behavior Response Study (BRS-08)

      DTIC Science & Technology

      2008-01-01

      pp. Evans, D.I. and G.R. England. (2001) Joint interim report Bahamas marine mammal stranding event of 15 – 16 March 2000. National Oceanographic...Providing Field Support for the Behavior Response Study (BRS-08) Diane Elaine Claridge Bahamas Marine Mammal Research Organisation P.O. Box AB...took place in 2008, known as BRS-08. Specific objectives were: 1) To work with the Marine Mammal Monitoring (M3R) program at the Atlantic Undersea

    4. Activation of myeloid and endothelial cells by CD40L gene therapy supports T-cell expansion and migration into the tumor microenvironment.

      PubMed

      Eriksson, E; Moreno, R; Milenova, I; Liljenfeldt, L; Dieterich, L C; Christiansson, L; Karlsson, H; Ullenhag, G; Mangsbo, S M; Dimberg, A; Alemany, R; Loskog, A

      2017-02-01

      CD40 is an interesting target in cancer immunotherapy due to its ability to stimulate T-helper 1 immunity via maturation of dendritic cells and to drive M2 to M1 macrophage differentiation. Pancreatic cancer has a high M2 content that has shown responsive to anti-CD40 agonist therapy and CD40 may thus be a suitable target for immune activation in these patients. In this study, a novel oncolytic adenovirus armed with a trimerized membrane-bound extracellular CD40L (TMZ-CD40L) was evaluated as a treatment of pancreatic cancer. Further, the CD40L mechanisms of action were elucidated in cancer models. The results demonstrated that the virus transferring TMZ-CD40L had oncolytic capacity in pancreatic cancer cells and could control tumor progression. TMZ-CD40L was a potent stimulator of human myeloid cells and T-cell responses. Further, CD40L-mediated stimulation increased tumor-infiltrating T cells in vivo, which may be due to a direct activation of endothelial cells to upregulate receptors for lymphocyte attachment and transmigration. In conclusion, CD40L-mediated gene therapy is an interesting concept for the treatment of tumors with high levels of M2 macrophages, such as pancreatic cancer, and an oncolytic virus as carrier of CD40L may further boost tumor killing and immune activation.

    5. A reproducible method for the isolation and expansion of ovine mesenchymal stromal cells from bone marrow for use in regenerative medicine preclinical studies.

      PubMed

      Caminal, Marta; Vélez, Roberto; Rabanal, Rosa Maria; Vivas, Daniel; Batlle-Morera, Laura; Aguirre, Màrius; Barquinero, Jordi; García, Joan; Vives, Joaquim

      2016-11-18

      The use of multipotent mesenchymal stromal cells (MSCs) as candidate medicines for treating a variety of pathologies is based on their qualities as either progenitors for the regeneration of damaged tissue or producers of a number of molecules with pharmacological properties. Preclinical product development programmes include the use of well characterized cell populations for proof of efficacy and safety studies before testing in humans. In the field of orthopaedics, an increasing number of translational studies use sheep as an in vivo test system because of the similarities with humans in size and musculoskeletal architecture. However, robust and reproducible methods for the isolation, expansion, manipulation and characterization of ovine MSCs have not yet been standardised. The present study describes a method for isolation and expansion of fibroblastic-like, adherent ovine MSCs that express CD44, CD90, CD140a, CD105 and CD166, and display trilineage differentiation potential. The 3-week bioprocess proposed here typically yielded cell densities of 1.4 × 10(4) MSCs/cm(2) at passage 2, with an expansion factor of 37.8 and approximately eight cumulative population doublings. The osteogenic potential of MSCs derived following this methodology was further evaluated in vivo in a translational model of osteonecrosis of the femoral head, in which the persistence of grafted cells in the host tissue and their lineage commitment into osteoblasts and osteocytes was demonstrated by tracking enhanced green fluorescent protein-labelled cells. Copyright © 2016 John Wiley & Sons, Ltd.

    6. Implementation of Active Support in Victoria, Australia: An Exploratory Study

      ERIC Educational Resources Information Center

      Mansell, Jim; Beadle-Brown, Julie; Bigby, Christine

      2013-01-01

      Background: Active support is an effective intervention to support engagement of residents with intellectual disability in group homes. This survey explored resident characteristics of the people supported by organisations implementing active support, the provision of active support, its procedures and systems, and resident engagement in…

    7. Implementation of Active Support in Victoria, Australia: An Exploratory Study

      ERIC Educational Resources Information Center

      Mansell, Jim; Beadle-Brown, Julie; Bigby, Christine

      2013-01-01

      Background: Active support is an effective intervention to support engagement of residents with intellectual disability in group homes. This survey explored resident characteristics of the people supported by organisations implementing active support, the provision of active support, its procedures and systems, and resident engagement in…

    8. Expansive Openness in Teacher Practice

      ERIC Educational Resources Information Center

      Kimmons, Royce

      2016-01-01

      Background/Context: Previous work on the use of open educational resources in K-12 classrooms has generally focused on issues related to cost. The current study takes a more expansive view of openness that also accounts for adaptation and sharing in authentic classroom contexts. Purpose/Objective/Research Question/Focus of Study The study seeks to…

    9. First-principles study on the thermal expansion of Ni-X binary alloys based on the quasi-harmonic Debye model

      NASA Astrophysics Data System (ADS)

      Shin, Yongjin; Jung, Woo-Sang; Lee, Young-Su

      2016-11-01

      In this study, we use the quasi-harmonic Debye model to predict the coefficient of thermal expansion of Ni- X binary alloys. The method bridges between the macroscopic elastic behavior and thermodynamic properties of materials without an expensive calculation of the volume dependence of the phonon density of states. Furthermore, the Grüneisen parameter is derived from the volume dependence of the Debye temperature, which is calculated from the first-principles elastic stiffness constants. The experimental coefficient of thermal expansion (CTE) of pure nickel is well reproduced, especially in the low temperature region. Among the few alloying elements tested, Al is predicted to slightly decrease the CTE whereas Mo and W are more effective in reducing the CTE. For the cases of Ni-X binary alloy systems, where the variation in the CTE is relatively small, the method used here appears to perform better than certain other formulations that rely entirely on the energy vs. volume relationship.

    10. Will the world run out of land? A Kaya-type decomposition to study past trends of cropland expansion

      NASA Astrophysics Data System (ADS)

      Huber, Veronika; Neher, Ina; Bodirsky, Benjamin L.; Höfner, Kathrin; Schellnhuber, Hans Joachim

      2014-01-01

      Globally, the further expansion of cropland is limited by the availability of adequate land and by the necessity to spare land for nature conservation and carbon sequestration. Analyzing the causes of past land-use changes can help to better understand the potential drivers of land scarcities of the future. Using the FAOSTAT database, we quantify the contribution of four major factors, namely human population growth, rising per-capita caloric consumption (including food intake and household waste), processing losses (including conversion of vegetal into animal products and non-food use of crops), and yield gains, to cropland expansion rates of the past (1961-2007). We employ a Kaya-type decomposition method that we have adapted to be applicable to drivers of cropland expansion at global and national level. Our results indicate that, all else equal, without the yield gains observed globally since 1961, additional land of the size of Australia would have been put under the plough by 2007. Under this scenario the planetary boundary on global cropland use would have already been transgressed today. By contrast, without rising per-capita caloric consumption and population growth since 1961, an area as large as nearly half and all of Australia could have been spared, respectively. Yield gains, with strongest contributions from maize, wheat and rice, have approximately offset the increasing demand of a growing world population. Analyses at the national scale reveal different modes of land-use transitions dependent on development stage, dietary standards, and international trade intensity of the countries. Despite some well-acknowledged caveats regarding the non-independence of decomposition factors, these results contribute to the empirical ranking of different drivers needed to set research priorities and prepare well-informed projections of land-use change until 2050 and beyond.

    11. Will the world run out of land? A Kaya-like-decomposition to study past trends of cropland expansion

      NASA Astrophysics Data System (ADS)

      Huber, V.; Neher, I.; Bodirsky, B.

      2011-12-01

      Around 12 % of the global ice-free land cover is currently used as cropland. Further expansion is limited by the amount of adequate land and even more so by the necessity to spare land for nature conservation and carbon sequestration. Analyzing the causes of past land-use changes with an integrative global approach can help to better understand the potential land scarcities of the future. Using the FAOSTAT database, we quantify the contribution of five major factors, namely human population growth, rising caloric demands, shifting diets, waste intensity, and yield gains, to cropland expansion rates of the past (1961-2007). We employ a Kaya-like-decomposition method that we have adapted to be applicable to drivers of cropland expansion at global, regional, and national level. Our results indicate that, all else equal, without the yield gains observed since 1961 the world would have used 63% more cropland area in 2007. Under this scenario the sustainable limit of cropland area would have already been transgressed today. By contrast, without population growth and rising caloric demands since 1961 the crop demand could have been fulfilled with 33% and 79% of currently used cropland area, respectively. Yield gains, with strongest contributions from maize, wheat and rice, have roughly offset the increasing demand of a growing world population. Analyses at the regional and local scale reveal different modes of land-use transitions dependent on development stage and dietary preferences of the countries. These results contribute to the empirical basis needed to prepare well-informed projections of land-use change until 2050 and beyond.

    12. Three-carbon Dowd-Beckwith ring expansion reaction versus intramolecular 1,5-hydrogen transfer reaction: a theoretical study.

      PubMed

      Ardura, Diego; Sordo, Tomás L

      2005-11-11

      [Reaction: see text]. The evolution of the primary radicals formed by addition of AIBN/HSnBu3 to methyl 1-(3-iodopropyl)-5-oxocyclopentanecarboxylate, methyl (1R,2R)-1-(3-iodopropyl)-2-methyl-5-oxocyclopentanecarboxylate, and methyl (1R,2S)-1-(3-iodopropyl)-2-methyl-5-oxocyclopentanecarboxylate in benzene has been theoretically investigated by ROMP2/6-311++G(2d,2p)//UB3LYP/6-31G(d,p) calculations taking into account the effect of solvent through a PCM-UAHF model. According to the theoretical results, for methyl 1-(3-iodopropyl)-5-oxocyclopentanecarboxylate and methyl (1R,2S)-1-(3-iodopropyl)-2-methyl-5-oxocyclopentanecarboxylate the major product is the cyclooctane derivative from the three-carbon ring expansion, whereas for methyl (1R,2R)-1-(3-iodopropyl)-2-methyl-5-oxocyclopentanecarboxylate the major product is that corresponding to the 1,5-H transposition in agreement with the experimental findings. This different behavior is a consequence of several factors determining the relative energy barriers. The methyl substituent destabilizes the ring expansion process for methyl (1R,2R)-1-(3-iodopropyl)-2-methyl-5-oxocyclopentanecarboxylate because of steric repulsion but favors it in the case of the beta-trans-substituted substrate because it makes possible the evolution of the system along more favorable conformations. The methyl group also favors the 1,5-H transposition rendering the transposed product a tertiary radical. The second stage of the ring expansion process is stabilized by resonance.

    13. 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.

    14. Space station environmental control and life support systems conceptual studies

      NASA Technical Reports Server (NTRS)

      Humphries, W. R.; Powell, L. E.

      1985-01-01

      It is pointed out that the establishment of a permanent manned Space Station requires the development of a comprehensive approach which combines new technologies and existing spacecraft subsystem capabilities into an optimum design. The present paper is concerned with studies which were conducted in connection with the development of the regenerative Environmental Control and Life Support Systems (ECLSS) for the Space Station. Attention is given to the current state of the ECLSS subsystems and system level analytical selection and group studies related to the integrated system conceptual design.

    15. 46 CFR 154.432 - Expansion and contraction.

      Code of Federal Regulations, 2014 CFR

      2014-10-01

      ... 46 Shipping 5 2014-10-01 2014-10-01 false Expansion and contraction. 154.432 Section 154.432... Membrane Tanks § 154.432 Expansion and contraction. The support system of a membrane tank must allow for thermal and physical expansion and contraction of the tank. Semi-Membrane Tanks ...

    16. 46 CFR 154.432 - Expansion and contraction.

      Code of Federal Regulations, 2010 CFR

      2010-10-01

      ... 46 Shipping 5 2010-10-01 2010-10-01 false Expansion and contraction. 154.432 Section 154.432... Membrane Tanks § 154.432 Expansion and contraction. The support system of a membrane tank must allow for thermal and physical expansion and contraction of the tank. Semi-Membrane Tanks ...

    17. 46 CFR 154.432 - Expansion and contraction.

      Code of Federal Regulations, 2011 CFR

      2011-10-01

      ... 46 Shipping 5 2011-10-01 2011-10-01 false Expansion and contraction. 154.432 Section 154.432... Membrane Tanks § 154.432 Expansion and contraction. The support system of a membrane tank must allow for thermal and physical expansion and contraction of the tank. Semi-Membrane Tanks ...

    18. 46 CFR 154.432 - Expansion and contraction.

      Code of Federal Regulations, 2013 CFR

      2013-10-01

      ... 46 Shipping 5 2013-10-01 2013-10-01 false Expansion and contraction. 154.432 Section 154.432... Membrane Tanks § 154.432 Expansion and contraction. The support system of a membrane tank must allow for thermal and physical expansion and contraction of the tank. Semi-Membrane Tanks ...

    19. 46 CFR 154.432 - Expansion and contraction.

      Code of Federal Regulations, 2012 CFR

      2012-10-01

      ... 46 Shipping 5 2012-10-01 2012-10-01 false Expansion and contraction. 154.432 Section 154.432... Membrane Tanks § 154.432 Expansion and contraction. The support system of a membrane tank must allow for thermal and physical expansion and contraction of the tank. Semi-Membrane Tanks ...

    20. Skeletal and dentoalveolar changes after miniscrew-assisted rapid palatal expansion in young adults: A cone-beam computed tomography study

      PubMed Central

      Park, Jung Jin; Park, Young-Chel; Lee, Kee-Joon; Cha, Jung-Yul; Tahk, Ji Hyun

      2017-01-01

      Objective The aim of this study was to evaluate the skeletal and dentoalveolar changes after miniscrew-assisted rapid palatal expansion (MARPE) in young adults by cone-beam computed tomography (CBCT). Methods This retrospective study included 14 patients (mean age, 20.1 years; range, 16–26 years) with maxillary transverse deficiency treated with MARPE. Skeletal and dentoalveolar changes were evaluated using CBCT images acquired before and after expansion. Statistical analyses were performed using paired t-test or Wilcoxon signed-rank test according to normality of the data. Results The midpalatal suture was separated, and the maxilla exhibited statistically significant lateral movement (p < 0.05) after MARPE. Some of the landmarks had shifted forwards or upwards by a clinically irrelevant distance of less than 1 mm. The amount of expansion decreased in the superior direction, with values of 5.5, 3.2, 2.0, and 0.8 mm at the crown, cementoenamel junction, maxillary basal bone, and zygomatic arch levels, respectively (p < 0.05). The buccal bone thickness and height of the alveolar crest had decreased by 0.6–1.1 mm and 1.7–2.2 mm, respectively, with the premolars and molars exhibiting buccal tipping of 1.1°–2.9°. Conclusions Our results indicate that MARPE is an effective method for the correction of maxillary transverse deficiency without surgery in young adults. PMID:28337417

    1. Polynomial expansion Monte Carlo study of frustrated itinerant electron systems: Application to a spin-ice type Kondo lattice model on a pyrochlore lattice

      NASA Astrophysics Data System (ADS)

      Ishizuka, Hiroaki; Udagawa, Masafumi; Motome, Yukitoshi

      2013-12-01

      We present the benchmark of the polynomial expansion Monte Carlo method to a Kondo lattice model with classical localized spins on a geometrically frustrated lattice. The method enables us to reduce the calculation amount by using the Chebyshev polynomial expansion of the density of states compared to a conventional Monte Carlo technique based on the exact diagonalization of the fermion Hamiltonian matrix. Further reduction is brought about by a real-space truncation of the vector-matrix operations. We apply the method to the model with spin-ice type Ising spins on a three-dimensional pyrochlore lattice and carefully examine the convergence in terms of the order of polynomials and the truncation distance. We find that, in a wide range of electron density at a relatively weak Kondo coupling compared to the noninteracting bandwidth, the results by the polynomial expansion method show good convergence to those by the conventional method within reasonable numbers of polynomials. This enables us to study the systems up to 4×83=2048 sites, while the previous study by the conventional method was limited to 4×43=256 sites. On the other hand, the real-space truncation is not helpful in reducing the calculation amount for the system sizes that we reached, as the sufficient convergence is obtained when most of the sites are involved within the truncation distance. The necessary truncation distance, however, appears not to show significant system size dependence, suggesting that the truncation method becomes efficient for larger system sizes.

    2. Interdisciplinary Exploration Supports Sternberg's Expansion of Giftedness

      ERIC Educational Resources Information Center

      Ambrose, Don

      2017-01-01

      Robert Sternberg's (2017) Active Concerned Citizenship and Ethical Leadership (ACCEL) framework provides a helpful way to align gifted education with the complexities of 21st-century socioeconomic and cultural environments. The recommendation that we shift away from pseudoquantitative precision in conceptions of giftedness aligns with similar…

    3. Novel chemical attempts at ex vivo hematopoietic stem cell expansion.

      PubMed

      Zhang, Yu; Gao, Yingdai

      2016-05-01

      Hematopoietic stem cells (HSCs) are the most extensively studied stem cell type in adults, and the only stem cell type with proof of clinical utility. However, the greatest challenge for the broader use of HSCs remains the true expansion of the stem cells ex vivo. The development of researches on small-molecule compounds that support the safe and efficient ex vivo expansion of HSCs would help to promote the clinical application of HSCs. In recent years, several novel small-molecule compounds have been reported to improve ex vivo HSC expansion by promoting self-renewal, delaying differentiation, increasing homing, and inhibiting apoptosis. Here, we review recent chemical developments in stem cell research and the mechanisms underlying these compounds' effects.

    4. Advanced Platform Systems Technology study. Volume 3: Supporting data

      NASA Technical Reports Server (NTRS)

      1983-01-01

      The overall study effort proceeded from the identification of 106 technology topics to the selection of 5 for detail trade studies. The technical issues and options were evaluated through the trade process. Finally, individual consideration was given to costs and benefits for the technologies identified for advancement. Eight priority technology items were identified for advancement. Supporting data generated during the trade selection and trade study process were presented. Space platform requirements, trade study and cost benefits analysis, and technology advancement planning are advanced. The structured approach used took advantage of a number of forms developed to ensure that a consistent approach was employed by each of the diverse specialists that participated. These forms were an intrinsic part of the study protocol.

    5. Implementation of active support in Victoria, Australia: an exploratory study.

      PubMed

      Mansell, Jim; Beadle-Brown, Julie; Bigby, Christine

      2013-03-01

      Active support is an effective intervention to support engagement of residents with intellectual disability in group homes. This survey explored resident characteristics of the people supported by organisations implementing active support, the provision of active support, its procedures and systems, and resident engagement in meaningful activity and relationships. Information was collected through questionnaires and direct observation of 33 group homes from 6 organisations in Victoria, Australia, with a 5-10-year history of implementing active support. Residents with lower support needs were engaged with little staff contact or assistance. Use of active support systems and structures was mixed. Only one organisation consistently provided good active support. Administrative systems and structures are not sufficient to change staff interaction and thus resident experience. Shared supported accommodation services may represent an inefficient use of resources for more able residents, as staff resources are not maximised to support for resident engagement.

    6. An X-Ray and Radio Study of the Varying Expansion Velocities in Tycho’s Supernova Remnant

      NASA Astrophysics Data System (ADS)

      Williams, Brian J.; Chomiuk, Laura; Hewitt, John W.; Blondin, John M.; Borkowski, Kazimierz J.; Ghavamian, Parviz; Petre, Robert; Reynolds, Stephen P.

      2016-06-01

      We present newly obtained X-ray and radio observations of Tycho’s supernova remnant using Chandra and the Karl G. Jansky Very Large Array in 2015 and 2013/14, respectively. When combined with earlier epoch observations by these instruments, we now have time baselines for expansion measurements of the remnant of 12-15 years in the X-rays and 30 years in the radio. The remnant’s large angular size allows for proper motion measurements at many locations around the periphery of the blast wave. Consistent with earlier measurements, we find a clear gradient in the expansion velocity of the remnant, despite its round shape. The proper motions on the western and southwestern sides of the remnant are about a factor of two higher than those in the east and northeast. We showed in an earlier work that this is related to an offset of the explosion site from the geometric center of the remnant due to a density gradient in the ISM, and using our refined measurements reported here, we find that this offset is ˜23″ toward the northeast. An explosion center offset in such a circular remnant has implications for searches for progenitor companions in other remnants.

    7. Changes in skeletal and dental relationship in Class II Division I malocclusion after rapid maxillary expansion: a prospective study

      PubMed Central

      Baratieri, Carolina; Alves Jr, Matheus; Bolognese, Ana Maria; Nojima, Matilde C. G.; Nojima, Lincoln I.

      2014-01-01

      Objective To assess skeletal and dental changes immediately after rapid maxillary expansion (RME) in Class II Division 1 malocclusion patients and after a retention period, using cone beam computed tomography (CBCT) imaging. Methods Seventeen children with Class II, Division 1 malocclusion and maxillary skeletal transverse deficiency underwent RME following the Haas protocol. CBCT were taken before treatment (T1), at the end of the active expansion phase (T2) and after a retention period of 6 months (T3). The scanned images were measured anteroposteriorly (SNA, SNB, ANB, overjet and MR) and vertically (N-ANS, ANS-Me, N-Me and overbite). Results Significant differences were identified immediately after RME as the maxilla moved forward, the mandible moved downward, overjet increased and overbite decreased. During the retention period, the maxilla relapsed backwards and the mandible was displaced forward, leaving patients with an overall increase in anterior facial height. Conclusion RME treatment allowed more anterior than inferior positioning of the mandible during the retention period, thus significantly improving Class II dental relationship in 75% of the patients evaluated. PMID:25162569

    8. Changes in skeletal and dental relationship in Class II Division I malocclusion after rapid maxillary expansion: a prospective study.

      PubMed

      Baratieri, Carolina; Alves, Matheus; Bolognese, Ana Maria; Nojima, Matilde C G; Nojima, Lincoln I

      2014-01-01

      To assess skeletal and dental changes immediately after rapid maxillary expansion (RME) in Class II Division 1 malocclusion patients and after a retention period, using cone beam computed tomography (CBCT) imaging. Seventeen children with Class II, Division 1 malocclusion and maxillary skeletal transverse deficiency underwent RME following the Haas protocol. CBCT were taken before treatment (T1), at the end of the active expansion phase (T2) and after a retention period of 6 months (T3). The scanned images were measured anteroposteriorly (SNA, SNB, ANB, overjet and MR) and vertically (N-ANS, ANS-Me, N-Me and overbite). Significant differences were identified immediately after RME as the maxilla moved forward, the mandible moved downward, overjet increased and overbite decreased. During the retention period, the maxilla relapsed backwards and the mandible was displaced forward, leaving patients with an overall increase in anterior facial height. RME treatment allowed more anterior than inferior positioning of the mandible during the retention period, thus significantly improving Class II dental relationship in 75% of the patients evaluated.

    9. Anisotropic lattice thermal expansion of PbFeBO4: A study by X-ray and neutron diffraction, Raman spectroscopy and DFT calculations

      DOE PAGES

      Murshed, M. Mangir; Mendive, Cecilia B.; Curti, Mariano; ...

      2014-11-01

      We present the lattice thermal expansion of mullite-type PbFeBO4 in this study. The thermal expansion coefficients of the metric parameters were obtained from composite data collected from temperature-dependent neutron and X-ray powder diffraction between 10 K and 700 K. The volume thermal expansion was modeled using extended Grüneisen first-order approximation to the zero-pressure equation of state. The additive frame of the model includes harmonic, quasi-harmonic and intrinsic anharmonic potentials to describe the change of the internal energy as a function of temperature. Moreover, the unit-cell volume at zero-pressure and 0 K was optimized during the DFT simulations. Harmonic frequencies ofmore » the optical Raman modes at the Γ-point of the Brillouin zone at 0 K were also calculated by DFT, which help to assign and crosscheck the experimental frequencies. The low-temperature Raman spectra showed significant anomaly in the antiferromagnetic regions, leading to softening or hardening of some phonons. Selected modes were analyzed using a modified Klemens model. The shift of the frequencies and the broadening of the line-widths helped to understand the anharmonic vibrational behaviors of the PbO4, FeO6 and BO3 polyhedra as a function of temperature.« less

    10. Anisotropic lattice thermal expansion of PbFeBO4: A study by X-ray and neutron diffraction, Raman spectroscopy and DFT calculations

      SciTech Connect

      Murshed, M. Mangir; Mendive, Cecilia B.; Curti, Mariano; Nénert, Gwilherm; Kalita, Patricia E.; Lipinska, Kris; Cornelius, Andrew L.; Huq, Ashfia; Gesing, Thorsten M.

      2014-11-01

      We present the lattice thermal expansion of mullite-type PbFeBO4 in this study. The thermal expansion coefficients of the metric parameters were obtained from composite data collected from temperature-dependent neutron and X-ray powder diffraction between 10 K and 700 K. The volume thermal expansion was modeled using extended Grüneisen first-order approximation to the zero-pressure equation of state. The additive frame of the model includes harmonic, quasi-harmonic and intrinsic anharmonic potentials to describe the change of the internal energy as a function of temperature. Moreover, the unit-cell volume at zero-pressure and 0 K was optimized during the DFT simulations. Harmonic frequencies of the optical Raman modes at the Γ-point of the Brillouin zone at 0 K were also calculated by DFT, which help to assign and crosscheck the experimental frequencies. The low-temperature Raman spectra showed significant anomaly in the antiferromagnetic regions, leading to softening or hardening of some phonons. Selected modes were analyzed using a modified Klemens model. The shift of the frequencies and the broadening of the line-widths helped to understand the anharmonic vibrational behaviors of the PbO4, FeO6 and BO3 polyhedra as a function of temperature.

    11. Building Employer Capacity to Support Meaningful Employment for Persons with Developmental Disabilities: A Grounded Theory Study of Employment Support Perspectives.

      PubMed

      Rashid, Marghalara; Hodgetts, Sandra; Nicholas, David

      2017-08-29

      To explore strategies to build employer capacity to support people with DD in meaningful employment from perspective of employment support workers. A grounded theory study was conducted with 34 employment support individuals. A theoretical sampling approach was used to identify and recruit participants from multiple sites in Ontario and Alberta. Three main themes, with seven sub-themes, emerged: (1) experiences of supporting employment finding for people with DD, (2) institutional influences on employee experiences, and (3) attitudes, assumptions and stigma. Several recommendations related to building employer capacity were offered. Our findings provide insight on specific elements and strategies that can support building employer capacity for persons with DD.

    12. Expansion of Gutta-percha in contact with various concentrations of zinc oxide-eugenol sealer: A three-dimensional volumetric study using spiral computed tomography

      PubMed Central

      Tilakchand, Mahima; Jain, Abhishek; Naik, Balaram

      2016-01-01

      Aim: The purpose of this study was to evaluate the three-dimensional expansion of Gutta-percha (GP), at various powder/liquid ratios, of a zinc oxide-eugenol (ZOE)-based sealer using spiral computed tomography (SCT). Materials and Methods: Thirty-five freshly extracted human mandibular premolars were selected for this study. Cleaning and shaping were performed in all the teeth initially with hand K-files up to #25 and finally with RaCe rotary instruments (25/06). Teeth were randomly divided into five groups of 7 teeth each. Specimens were scanned using SCT. They were then viewed both cross-sectionally and longitudinally, with a constant thickness of 1 mm/slice. The volume of root canal in each tooth was estimated. Obturation was performed by GP points (25/04) and ZOE-based root canal sealer in all groups with different powder-liquid ratio. Groups 1, 2, 3, and 4, had powder/liquid ratio of 1:1, 1:2, 1:3, and 1:4, respectively, while in the control group, no sealer was used. The obturation was performed by sealer coated single cone GP. A second SCT scan was performed to determine the volume of GP and sealer in all four groups 1 day after obturation. The third and fourth SCT scans were taken 7 and 30 days after obturation, respectively. The mean volume of GP per group was calculated. Data were statistically analyzed using one-way ANOVA. Inter-group comparisons were done using Scheffe post hoc multiple comparisons test. Results: All groups with sealer showed expansion of GP at both 7th day and 30th day, which was statistically significant from the GP volume at 1st day. Groups 2 and 3 with powder/liquid ratio of 1:2 and 1:3 gave the highest mean volume values during 30 days period and showed significant expansion in comparison with Groups 1 and 4 with powder/liquid ratio of 1:1 and 1:4, respectively. Conclusion: Increasing the ratio of eugenol in sealer resulted in the volumetric expansion of GP. However, further studies should be performed to confirm the expansion of

    13. SAMICS support study. Volume 1: Cost account catalog

      NASA Technical Reports Server (NTRS)

      1977-01-01

      The Jet Propulsion Laboratory (JPL) is examining the feasibility of a new industry to produce photovoltaic solar energy collectors similar to those used on spacecraft. To do this, a standardized costing procedure was developed. The Solar Array Manufacturing Industry Costing Standards (SAMICS) support study supplies the following information: (1) SAMICS critique; (2) Standard data base--cost account structure, expense item costs, inflation rates, indirect requirements relationships, and standard financial parameter values; (3) Facilities capital cost estimating relationships; (4) Conceptual plant designs; (5) Construction lead times; (6) Production start-up times; (7) Manufacturing price estimates.

    14. An empirical study of early childhood support through partnership building.

      PubMed

      Wang, Jianjun; Ortiz, Theresa; Navarro, Diana; Maier, Roland; Wang, Summer; Wang, Lisa; Wang, Libing

      2016-12-01

      The first five years were recognized as a critical period of child growth. Accordingly, California voters approved tobacco tax through Proposition 10 to fund early childhood services since 1998. Due to the state revenue decline, Service Integration has been advocated to enhance program supports in Child Health, Family Functioning, and Child Development. In this study, interview data are analyzed to examine the partnership building among 40 programs. The results indicate a significant impact of the service outreach across remote communities in Kern County, California. In addition, contextual information is provided to facilitate interpretation of the partnership strength from a social network analysis. Enhancement of this investigation is discussed in light of future development.

    15. Life support system definition study for long duration planetary missions

      NASA Technical Reports Server (NTRS)

      Slavin, T.; Meyer, P.; Reysa, R.

      1989-01-01

      The development of a mission planners life support systems (LSS) guidebook for providing data on the impact of various LSS on mission parameters such as mass, power, and volume is discussed. The factors utilized to define LSS case study mission drivers, and driver and mission impact parameter definitions are described. An example of a guidebook table for a specific set of LSS drivers is provided. Four approaches for physical/chemical closed-loop LSS are examined. A preliminary LSS guidebook for a lunar base is presented.

    16. Prospective study of nutritional support during pelvic irradiation

      SciTech Connect

      Kinsella, T.J.; Malcolm, A.W.; Bothe, A. Jr.; Valerio, D.; Blackburn, G.L.

      1981-04-01

      A prospective study of nutritional support during pelvic irradiation was carried out in 32 patients with a primary pelvic malignancy and prior weight loss. Both curative and palliative patients were eligible for the study. Seventeen patients were randomized to receive intravenous hyperalimentation (IVH) and fifteen patients served as controls who were maintained on their regular diet. Patients were stratified by percent body weight loss. Tolerance to therapy was assessed by evaluation of functional status and by using nutritional parameters of body weight change, change in serum protein levels, and response to delayed hypersensitivity skin tests. The curative IVH group tolerated therapy well by both functional and nutritional measurements. All curative IVH patients completed the planned radiation therapy without a treatment break and were fully active following treatment. Patients gained an average of 4.0 kg body weight during irradiation, which was significantly different from the curative control patients. They demonstrated a significant increase in serum transferrin reflecting an improvement in visceral protein. In addition, all showed a positive response to delayed hypersensitivity skin tests at the completion of irradiation. The palliative IVH patients often did poorly because of progression of disease and demonstrated only an elevation of serum transferrin during treatment. The results in the curative IVH group suggest a potential adjunctive role for intravenous hyperalimentation in the malnourished cancer patient undergoing pelvic irradiation. Clearly, further study of nutritional support during pelvic irradiation is needed using curative patients with a single tumor type and significant prior weight loss.

    17. Supported Lipid Bilayer Technology for the Study of Cellular Interfaces

      PubMed Central

      Crites, Travis J.; Maddox, Michael; Padhan, Kartika; Muller, James; Eigsti, Calvin; Varma, Rajat

      2015-01-01

      Glass-supported lipid bilayers presenting freely diffusing proteins have served as a powerful tool for studying cell-cell interfaces, in particular, T cell–antigen presenting cell (APC) interactions, using optical microscopy. Here we expand upon existing protocols and describe the preparation of liposomes by an extrusion method, and describe how this system can be used to study immune synapse formation by Jurkat cells. We also present a method for forming such lipid bilayers on silica beads for the study of signaling responses by population methods, such as western blotting, flow cytometry, and gene-expression analysis. Finally, we describe how to design and prepare transmembrane-anchored protein-laden liposomes, following expression in suspension CHO (CHOs) cells, a mammalian expression system alternative to insect and bacterial cell lines, which do not produce mammalian glycosylation patterns. Such transmembrane-anchored proteins may have many novel applications in cell biology and immunology. PMID:26331983

    18. Evaluation of Empirical Data and Modeling Studies to Support ...

      EPA Pesticide Factsheets

      This study is an evaluation of empirical data and select modeling studies of the behavior of petroleum hydrocarbon (PHC) vapors in subsurface soils and how they can affect subsurface-to-indoor air vapor intrusion (VI), henceforth referred to as petroleum vapor intrusion or “PVI” for short. The purpose of this study is to support the development of a soil vapor screening methodology for PHC compounds for the U.S. Environmental Protection Agency’s Office of Underground Storage Tanks (U.S. EPA OUST); consequently, the focus is primarily on characterizing PVI at Subtitle I underground storage tank (UST) sites with petroleum fuel releases. However, PVI data from other types of sites (fuel terminals, petroleum refineries) are also presented and discussed

    19. Angiopoietin-like proteins stimulate ex vivo expansion of hematopoietic stem cells.

      PubMed

      Zhang, Cheng Cheng; Kaba, Megan; Ge, Guangtao; Xie, Kathleen; Tong, Wei; Hug, Christopher; Lodish, Harvey F

      2006-02-01

      Successful ex vivo expansion of hematopoietic stem cells (HSCs) would greatly benefit the treatment of disease and the understanding of crucial questions of stem cell biology. Here we show, using microarray studies, that the HSC-supportive mouse fetal liver CD3(+) cells specifically express the proteins angiopoietin-like 2 (Angptl2) and angiopoietin-like 3 (Angptl3). We observed a 24- or 30-fold net expansion of long-term HSCs by reconstitution analysis when we cultured highly enriched HSCs for 10 days in the presence of Angptl2 or Angptl3 together with saturating levels of other growth factors. The coiled-coil domain of Angptl2 was capable of stimulating expansion of HSCs. Furthermore, angiopoietin-like 5, angiopoietin-like 7 and microfibril-associated glycoprotein 4 also supported expansion of HSCs in culture.

    20. Study on supporting force sensing and control during large aperture space mirror test

      NASA Astrophysics Data System (ADS)

      Zhang, Long; Hu, Wenqi; Zheng, Liehua; Hao, Peiming

      2016-10-01

      During the machining of large aperture lightweight space mirror, the mirror figure consistency between ground test and space mission is a problem. In order to effectively control the supporting deformation effect on test results in gravity environment, in view of a 1.2-m space mirror with back blind holes, a supporting method for optical axis horizontal test is proposed, with this method, mirror under test is positioned by three center hole surfaces and supported by six external hole surfaces. The effect of deformation caused by different supporting force value, area and position is analyzed by finite element method, the simulation results show that this supporting method can control the mirror supporting deformation within PV0.035λ rms0.005λ. The actual supporting system uses soft expansion mandrel to control the mirror position and pneumatic lever to realize the floating support. In order to ensure that the support force can evenly distribute on the contact surface, a pressure mapping system is adopted to measure the interface pressure between the mirror blind holes and the soft supporting pads for the first time. This method can meet the test requirements of rms=1/40λ mirror and provides a technical support for high precision test of large aperture space mirror with back blind holes.

    1. Effects of lateral osteotomy on surgically assisted rapid maxillary expansion.

      PubMed

      Oliveira, T F M; Pereira-Filho, V A; Gabrielli, M A C; Gonçales, E S; Santos-Pinto, A

      2016-04-01

      This study aimed to assess the potential effects of two different osteotomy designs of the maxillary lateral wall on dental and skeletal changes after surgically assisted rapid maxillary expansion (SARME). Thirty adult patients were divided into two groups according to the lateral osteotomy design: group 1 (n=16) underwent lateral osteotomy performed in a horizontal straight fashion, and group 2 (n=14) underwent lateral osteotomy performed in parallel to the occlusal plane with a step at the zygomatic buttress. Cone beam computed tomography scans were obtained preoperatively (T1), immediately after expansion (T2), and 6 months after expansion (T3). Mixed analysis of variance (ANOVA) was used for the statistical analysis. The results showed no significant interaction effect between groups and time points. Therefore, maxillary expansion was effective in both groups. Statistically significant increases in all dental and skeletal measurements were observed immediately after expansion (P<0.001). Relapse of the nasal floor width, tipping of the supporting teeth, and an increase in root distance in molars occurred at T3 (P<0.05). In summary, the maxillary lateral osteotomy design did not influence the results of SARME, which occurred mainly through the inclination of maxillary segments.

    2. A High-Resolution Microwave Study of the Conformations of Butan-2-ol in a Supersonic Expansion.

      PubMed

      King; Howard

      2001-01-01

      The microwave Fourier transform spectrum of the chiral, secondary alcohol butan-2-ol has been recorded in the range 6-18 GHz. The spectrum is relatively dense, due to the large number of species formed in the supersonic expansion used. Three conformational isomers of the butan-2-ol molecule have been identified and their spectra assigned using a semirigid, asymmetric-rotor model. They correspond to the three configurations that the central C-C bond can adopt. The basis of our assignment is a series of ab initio calculations, which have been performed using the GAUSSIAN 94 package, good agreement being observed between theoretical and experimental values of the rotational constants. First-order centrifugal distortion coefficients have also been extracted. It has proven possible, by examination of the relative strengths of a-, b-, and c-type transitions, to infer some further information about the position of the hydroxyl hydrogen atom within each conformer. Copyright 2001 Academic Press.

    3. A STUDY OF THE PROPERTIES OF CP: COEFFICIENT OF THERMAL EXPANSION, DECOMPOSITION KINETICS AND REACTION TO SPARK, FRICTION AND IMPACT

      SciTech Connect

      Weese, R K; Burnham, A K; Fontes, A T

      2005-03-30

      The properties of pentaamine (5-cyano-2H-tetrazolato-N2) cobalt (III) perchlorate (CP), which was first synthesized in 1968, continues to be of interest for predicting behavior in handling, shipping, aging, and thermal cook-off situations. We report coefficient of thermal expansion (CTE) values over four specific temperature ranges, decomposition kinetics using linear heating rates, and the reaction to three different types of stimuli: impact, spark, and friction. The CTE was measured using a Thermal Mechanical Analyzer (TMA) for samples that were uniaxially compressed at 10,000 psi and analyzed over a dynamic temperature range of -20 C to 70 C. Using differential scanning calorimetry, DSC, CP was decomposed at linear heating rates of 1, 3, and 7 C/min and the kinetic triplet calculated using the LLNL code Kinetics05. Values are also reported for spark, friction, and impact sensitivity.

    4. Relativistic effects on plasma expansion

      SciTech Connect

      Benkhelifa, El-Amine; Djebli, Mourad

      2014-07-15

      The expansion of electron-ion plasma is studied through a fully relativistic multi-fluids plasma model which includes thermal pressure, ambipolar electrostatic potential, and internal energy conversion. Numerical investigation, based on quasi-neutral assumption, is performed for three different regimes: nonrelativistic, weakly relativistic, and relativistic. Ions' front in weakly relativistic regime exhibits spiky structure associated with a break-down of quasi-neutrality at the expanding front. In the relativistic regime, ion velocity is found to reach a saturation limit which occurs at earlier stages of the expansion. This limit is enhanced by higher electron velocity.

    5. Influence of the expansion screw height on the dental effects of the hyrax expander: a study with finite elements.

      PubMed

      Araugio, Rafael Marques de Sousa; Landre, Jánes; Silva, Diana de Lourdes Almeida; Pacheco, Wellington; Pithon, Matheus Melo; Oliveira, Dauro Douglas

      2013-02-01

      Our objective was to evaluate the influence of the expansion screw height of a hyrax expander on the degree of dental inclination during rapid maxillary expansion by using the finite element method. The hyrax expander and the maxillary arch were modeled by using Solidworks software (Dassault Systèmes, Paris, France). Three distinct finite element method models were created by simulating different screw heights relative to the plane that intersected the center of resistance of the maxillary first molars. These 3 relative positions were 10 mm below the maxillary first molars' center of resistance, at the same level as the maxillary first molars' center of resistance, and 10 mm above the maxillary first molars' center of resistance. The initial activation of the expanders was simulated, and tooth displacements for each finite element method model were registered in the buccolingual, corono-apical, and mesiodistal directions. The simulations tested showed that the 3 hyrax screw heights had different dental tipping tendencies. When the screw was simulated below the maxillary first molars' center of resistance, buccal tipping of the crowns and lingual tipping of the roots were registered. This tendency decreased when the screw was simulated at the same level as the maxillary first molars' center of resistance. However, when the screw was simulated above the maxillary first molars' center of resistance, the tipping tendency was inverted, with the crowns displaying lingual tipping and the roots displaying buccal tipping. These findings might explain the importance of carefully planning the height of the hyrax expander screw, since, depending on this position, different tooth movements can be achieved. From an orthopedic perspective, the ideal screw position might be slightly above the maxillary first molars' center of resistance; this would generate less dental tipping. Copyright © 2013 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

    6. [Clinical study on efficacy of nasal surgical expansion as a basic operation in treatment of patients with OSAHS].

      PubMed

      Hui, Peilin; Xie, Yuping; Ma, Wei; Zhao, Lijun; Wang, Jinfeng; Wei, Xiaoquan; Zhou, Liya; Xu, Chao; Zhao, Gang; Hou, Yiping

      2015-11-01

      To observe the clinical effect of nasal surgical expansion as basical surgical treatment of patients with OSAHS. A total of 320 patients with OSAHS were retrospectively analyzed. The patient was diagnosed by PSG. The electronic nasopharyngolarygnoscope exam airway CT, and MRI were applied to determining the nasal plane block. According to the concrete reasons, the nasal endoscopic nasal septum corrective surgery and open surgery were carried out, respectively. Nasal sinus neoplasm resection of off shoring, inferior turbinate fracture surgery or inferior turbinate back-end 1/3 line expansion and low temperature plasma ablation of nasal surgery, respectively. Pittsburgh sleep quality index (PSQI), snore outcome survey (SOS), epworth sleepiness score (ESS), the lowest arterial oxygen saturation (LSaO2) and AHI, time and ratio of slow wave sleep (SWS) stage and rapid eye movement (REM) stage were applied to comparing the curative effect between pre-operation and post-operation periods. Snoring, sleep apnea, subjective mental symptoms of all patients with OSAHS were improved after operation; PSQI, SOS and ESS score were improved compared to pretreatment (P < 0.05); according to the 2009 OSAHS diagnosis and curative effect evaluation standard, 38 cases cured, 189 cases had obvious effect, 93 cases effective, and the total effective rate was 100%; there was statistical difference between the pre-operative period and 6 months post-operative in PSQI, SOS and ESS, LSaO2, AHI and proportion of REM (P < 0.05); sleep structure was improved, time and proportion of SWS were increased after the operation (P < 0.05). Solving the problem of nasal airway obstruction is the first step in surgical treatment of patients with OSAHS.

    7. Exemplary Social Studies Teachers Use of Computer-Supported Instruction in the Classroom

      ERIC Educational Resources Information Center

      Acikalin, Mehmet

      2010-01-01

      Educators increasingly support the use of computer-supported instruction in social studies education. However few studies have been conducted to study teacher use of computer-supported instruction in social studies education. This study was therefore designed to examine the use of exemplary social studies teachers' computer-supported instruction…

    8. An experimental study of laser supported hydrogen plasmas

      NASA Technical Reports Server (NTRS)

      Vanzandt, D. M.; Mccay, T. D.; Eskridge, R. H.

      1984-01-01

      The rudiments of a rocket thruster which receives its enthalpy from an energy source which is remotely beamed from a laser is described. An experimental study now partially complete is discussed which will eventually provide a detailed understanding of the physics for assessing the feasibility of using hydrogen plasmas for accepting and converting this energy to enthalpy. A plasma ignition scheme which uses a pulsed CO2 laser has been developed and the properties of the ignition spark documented, including breakdown intensities in hydrogen. A complete diagnostic system capable of determining plasma temperature and the plasma absorptivity for subsequent steady state absorption of a high power CO2 laser beam are developed and demonstrative use is discussed for the preliminary case study, a two atmosphere laser supported argon plasma.

    9. Experimental and theoretical study of heat transfer in constant-volume and compression-expansion systems including the effects of flame propagation

      SciTech Connect

      Woodard, J.B.

      1982-03-01

      The study of the heat transfer to the cylinder and piston surfaces in an internal combustion engine is of both practical and fundamental interest. Heat transfer processes are critical to the design and development of engines with respect to emissions, engine efficiency, and thermal stress in engine materials. In addition, experimental heat transfer data along with flame propagation results are needed to study and appraise analyses of the processes in engines. In this work, two studies of heat transfer phenomena are made. First an analysis of an observed reversal in the direction of the wall heat flux is presented. Then, an experimental study is reported in which simultaneous wall heat flux, pressure, and flame propagation data are obtained. In particular, the interaction of the flame propagation and wall heat transfer is discussed. An analytical solution for the reversal in direction of the wall heat flux during compression and expansion is derived. The results are in good agreement with experimental measurements. Temperature profiles were calculated. From these temperature profiles and the analytical solution of the wall heat flux, a physical explanation for the heat tranfer reversal is determined. Simultaneous measurements of pressure, wall temperature, wall heat flux, and flame location and shape were obtained for combustion in constant volume, expansion, and compression-expansion systems. The measurements showed that the wall temperature and heat flux rise rapidly when the flame passes. The flame speed, and correspondingly the time of the sharp rise in wall temperature and heat flux were found to vary considerably with equivalence ratio. For lean constant volume combustion, buoyancy was found to have a significant effect on the shape of the flame and on the corresponding wall temperature and heat flux variations.

    10. Anisotropic thermal expansion of strontium barium niobate

      NASA Astrophysics Data System (ADS)

      Qadri, Syed B.; Bellotti, Jeffrey A.; Garzarella, Anthony; Wu, Dong Ho

      2005-06-01

      Strontium barium niobate is a tungsten-bronze ferroelectric crystal having a tetragonal unit cell. Low-temperature x-ray diffraction studies were performed on a single crystal of Sr0.75Ba0.25Nb2O6 to determine the thermal expansivity along the a- and c-axes. Negative thermal expansion was observed along the c direction while a positive thermal expansion was measured along the a axis. The anisotropic thermal expansion behavior is explained as arising due to the geometry of the crystal structure.

    11. Virtually supportive: A feasibility pilot study of an online support group for dementia caregivers in a 3D virtual environment

      PubMed Central

      O’Connor, Mary-Frances; Arizmendi, Brian J.; Kaszniak, Alfred W.

      2014-01-01

      Caregiver support groups effectively reduce stress from caring for someone with dementia. These same demands can prevent participation in a group. The present feasibility study investigated a virtual online caregiver support group to bring the support group into the home. While online groups have been shown to be helpful, submissions to a message board (vs. live conversation) can feel impersonal. By using avatars, participants interacted via real-time chat in a virtual environment in an 8-week support group. Data indicated lower levels of perceived stress, depression and loneliness across participants. Importantly, satisfaction reports also indicate that caregivers overcame the barriers to participation, and had a strong sense of the group’s presence. This study provides the framework for an accessible and low cost online support group for a dementia caregiver. The study demonstrates the feasibility of interactive group in a virtual environment for engaging members in meaningful interaction. PMID:24984911

    12. Virtually supportive: a feasibility pilot study of an online support group for dementia caregivers in a 3D virtual environment.

      PubMed

      O'Connor, Mary-Frances; Arizmendi, Brian J; Kaszniak, Alfred W

      2014-08-01

      Caregiver support groups effectively reduce stress from caring for someone with dementia. These same demands can prevent participation in a group. The present feasibility study investigated a virtual online caregiver support group to bring the support group into the home. While online groups have been shown to be helpful, submissions to a message board (vs. live conversation) can feel impersonal. By using avatars, participants interacted via real-time chat in a virtual environment in an 8-week support group. Data indicated lower levels of perceived stress, depression and loneliness across participants. Importantly, satisfaction reports also indicate that caregivers overcame the barriers to participation, and had a strong sense of the group's presence. This study provides the framework for an accessible and low cost online support group for a dementia caregiver. The study demonstrates the feasibility of interactive group in a virtual environment for engaging members in meaningful interaction. Copyright © 2014 Elsevier Inc. All rights reserved.

    13. Rotational spectral studies of O(1D) insertion reactions with methane and ethylene: Methanol and vinyl alcohol in a supersonic expansion

      NASA Astrophysics Data System (ADS)

      Hays, Brian M.; Wehres, Nadine; DePrince, Bridget Alligood; Roy, Althea A. M.; Laas, Jacob C.; Widicus Weaver, Susanna L.

      2015-06-01

      We report a new apparatus for millimeter/submillimeter spectroscopic studies of O(1D) insertion reactions to produce molecules of astrophysical interest. This study focuses on the insertion of O(1D) into methane to form methanol, and the insertion of O(1D) into ethylene to form vinyl alcohol (CH2CHOH). The O(1D) was produced via laser photodissociation of O3 in a fused silica tube and mixed with a hydrocarbon before a supersonic expansion. Direct absorption millimeter/submillimeter spectroscopy was used to monitor the products. The methanol study was used as an experimental benchmark, while the vinyl alcohol study extended rotational spectroscopic measurements to higher frequencies. Observed products from both insertion reactions included, but were not limited to, H2CO, HO2, and CH3O. Methanol and vinyl alcohol were only produced in detectable quantities when the fused silica tube was included, indicating that collisions before the expansion are required for production and stabilization of the O(1D) insertion products.

    14. Cephalometric variables used to predict the success of interceptive treatment with rapid maxillary expansion and face mask. A longitudinal study.

      PubMed

      Nardoni, Daniele Nóbrega; Siqueira, Danilo Furquim; Cardoso, Mauricio de Almeida; Capelozza Filho, Leopoldino

      2015-01-01

      Prognosis is the main limitation of interceptive treatment of Class III malocclusions. The interceptive procedures of rapid maxillary expansion (RME) and face mask therapy performed in early mixed dentition are capable of achieving immediate overcorrection and maintenance of facial and occlusal morphology for a few years. Individuals presenting minimal acceptable faces at growth completion are potential candidates for compensatory orthodontic treatment, while those with facial involvement should be submitted to orthodontic decompensation for orthognathic surgery. To investigate cephalometric variables that might predict the outcomes of orthopedic treatment with RME and face mask therapy (FM). Cephalometric analysis of 26 Class III patients (mean age of 8 years and 4 months) was performed at treatment onset and after a mean period of 6 years and 10 months at pubertal growth completion, including a subjective facial analysis. Patients was divided into two groups: success group (21 individuals) and failure group (5 individuals). Discriminant analysis was applied to the cephalometric values at treatment onset. Two predictor variables were found by stepwise procedure. Orthopedic treatment of Class III malocclusion may have unfavorable prognosis at growth completion whenever initial cephalometric analysis reveals increased lower anterior facial height (LAFH) combined with reduced angle between the condylar axis and the mandibular plane (CondAx.MP). The results of treatment with RME and face mask therapy at growth completion in Class III patients could be predicted with a probability of 88.5%.

    15. Cephalometric variables used to predict the success of interceptive treatment with rapid maxillary expansion and face mask. A longitudinal study

      PubMed Central

      Nardoni, Daniele Nóbrega; Siqueira, Danilo Furquim; Cardoso, Mauricio de Almeida; Capelozza, Leopoldino

      2015-01-01

      INTRODUCTION: Prognosis is the main limitation of interceptive treatment of Class III malocclusions. The interceptive procedures of rapid maxillary expansion (RME) and face mask therapy performed in early mixed dentition are capable of achieving immediate overcorrection and maintenance of facial and occlusal morphology for a few years. Individuals presenting minimal acceptable faces at growth completion are potential candidates for compensatory orthodontic treatment, while those with facial involvement should be submitted to orthodontic decompensation for orthognathic surgery. OBJECTIVES: To investigate cephalometric variables that might predict the outcomes of orthopedic treatment with RME and face mask therapy (FM). METHODS: Cephalometric analysis of 26 Class III patients (mean age of 8 years and 4 months) was performed at treatment onset and after a mean period of 6 years and 10 months at pubertal growth completion, including a subjective facial analysis. Patients was divided into two groups: success group (21 individuals) and failure group (5 individuals). Discriminant analysis was applied to the cephalometric values at treatment onset. Two predictor variables were found by stepwise procedure. RESULTS: Orthopedic treatment of Class III malocclusion may have unfavorable prognosis at growth completion whenever initial cephalometric analysis reveals increased lower anterior facial height (LAFH) combined with reduced angle between the condylar axis and the mandibular plane (CondAx.MP). CONCLUSION: The results of treatment with RME and face mask therapy at growth completion in Class III patients could be predicted with a probability of 88.5%. PMID:25741830

    16. A Satellite Mortality Study to Support Space Systems Lifetime Prediction

      NASA Technical Reports Server (NTRS)

      Fox, George; Salazar, Ronald; Habib-Agahi, Hamid; Dubos, Gregory

      2013-01-01

      Estimating the operational lifetime of satellites and spacecraft is a complex process. Operational lifetime can differ from mission design lifetime for a variety of reasons. Unexpected mortality can occur due to human errors in design and fabrication, to human errors in launch and operations, to random anomalies of hardware and software or even satellite function degradation or technology change, leading to unrealized economic or mission return. This study focuses on data collection of public information using, for the first time, a large, publically available dataset, and preliminary analysis of satellite lifetimes, both operational lifetime and design lifetime. The objective of this study is the illustration of the relationship of design life to actual lifetime for some representative classes of satellites and spacecraft. First, a Weibull and Exponential lifetime analysis comparison is performed on the ratio of mission operating lifetime to design life, accounting for terminated and ongoing missions. Next a Kaplan-Meier survivor function, standard practice for clinical trials analysis, is estimated from operating lifetime. Bootstrap resampling is used to provide uncertainty estimates of selected survival probabilities. This study highlights the need for more detailed databases and engineering reliability models of satellite lifetime that include satellite systems and subsystems, operations procedures and environmental characteristics to support the design of complex, multi-generation, long-lived space systems in Earth orbit.

    17. A Satellite Mortality Study to Support Space Systems Lifetime Prediction

      NASA Technical Reports Server (NTRS)

      Fox, George; Salazar, Ronald; Habib-Agahi, Hamid; Dubos, Gregory

      2013-01-01

      Estimating the operational lifetime of satellites and spacecraft is a complex process. Operational lifetime can differ from mission design lifetime for a variety of reasons. Unexpected mortality can occur due to human errors in design and fabrication, to human errors in launch and operations, to random anomalies of hardware and software or even satellite function degradation or technology change, leading to unrealized economic or mission return. This study focuses on data collection of public information using, for the first time, a large, publically available dataset, and preliminary analysis of satellite lifetimes, both operational lifetime and design lifetime. The objective of this study is the illustration of the relationship of design life to actual lifetime for some representative classes of satellites and spacecraft. First, a Weibull and Exponential lifetime analysis comparison is performed on the ratio of mission operating lifetime to design life, accounting for terminated and ongoing missions. Next a Kaplan-Meier survivor function, standard practice for clinical trials analysis, is estimated from operating lifetime. Bootstrap resampling is used to provide uncertainty estimates of selected survival probabilities. This study highlights the need for more detailed databases and engineering reliability models of satellite lifetime that include satellite systems and subsystems, operations procedures and environmental characteristics to support the design of complex, multi-generation, long-lived space systems in Earth orbit.

    18. A satellite mortality study to support space systems lifetime prediction

      NASA Astrophysics Data System (ADS)

      Fox, George; Salazar, Ronald; Habib-Agahi, Hamid; Dubos, Gregory F.

      Estimating the operational lifetime of satellites and spacecraft is a complex process. Operational lifetime can differ from mission design lifetime for a variety of reasons. Unexpected mortality can occur due to human errors in design and fabrication, to human errors in launch and operations, to random anomalies of hardware and software or even satellite function degradation or technology change, leading to unrealized economic or mission return. This study focuses on data collection of public information using, for the first time, a large, publically available dataset, and preliminary analysis of satellite lifetimes, both operational lifetime and design lifetime. The objective of this study is the illustration of the relationship of design life to actual lifetime for some representative classes of satellites and spacecraft. First, a Weibull and Exponential lifetime analysis comparison is performed on the ratio of mission operating lifetime to design life, accounting for terminated and ongoing missions. Next a Kaplan-Meier survivor function, standard practice for clinical trials analysis, is estimated from operating lifetime. Bootstrap resampling is used to provide uncertainty estimates of selected survival probabilities. This study highlights the need for more detailed databases and engineering reliability models of satellite lifetime that include satellite systems and subsystems, operations procedures and environmental characteristics to support the design of complex, multi-generation, long-lived space systems in Earth orbit.

    19. Thermal Expansion "Paradox."

      ERIC Educational Resources Information Center

      Fakhruddin, Hasan

      1993-01-01

      Describes a paradox in the equation for thermal expansion. If the calculations for heating a rod and subsequently cooling a rod are determined, the new length of the cool rod is shorter than expected. (PR)

    20. Pen Branch delta expansion

      SciTech Connect

      Nelson, E.A.; Christensen, E.J.; Mackey, H.E.; Sharitz, R.R.; Jensen, J.R.; Hodgson, M.E.

      1984-02-01

      Since 1954, cooling water discharges from K Reactor ({anti X} = 370 cfs {at} 59 C) to Pen Branch have altered vegetation and deposited sediment in the Savannah River Swamp forming the Pen Branch delta. Currently, the delta covers over 300 acres and continues to expand at a rate of about 16 acres/yr. Examination of delta expansion can provide important information on environmental impacts to wetlands exposed to elevated temperature and flow conditions. To assess the current status and predict future expansion of the Pen Branch delta, historic aerial photographs were analyzed using both basic photo interpretation and computer techniques to provide the following information: (1) past and current expansion rates; (2) location and changes of impacted areas; (3) total acreage presently affected. Delta acreage changes were then compared to historic reactor discharge temperature and flow data to see if expansion rate variations could be related to reactor operations.

    1. Weakly relativistic plasma expansion

      SciTech Connect

      Fermous, Rachid Djebli, Mourad

      2015-04-15

      Plasma expansion is an important physical process that takes place in laser interactions with solid targets. Within a self-similar model for the hydrodynamical multi-fluid equations, we investigated the expansion of both dense and under-dense plasmas. The weakly relativistic electrons are produced by ultra-intense laser pulses, while ions are supposed to be in a non-relativistic regime. Numerical investigations have shown that relativistic effects are important for under-dense plasma and are characterized by a finite ion front velocity. Dense plasma expansion is found to be governed mainly by quantum contributions in the fluid equations that originate from the degenerate pressure in addition to the nonlinear contributions from exchange and correlation potentials. The quantum degeneracy parameter profile provides clues to set the limit between under-dense and dense relativistic plasma expansions at a given density and temperature.

    2. Thermal Expansion "Paradox."

      ERIC Educational Resources Information Center

      Fakhruddin, Hasan

      1993-01-01

      Describes a paradox in the equation for thermal expansion. If the calculations for heating a rod and subsequently cooling a rod are determined, the new length of the cool rod is shorter than expected. (PR)

    3. Thermal-Expansion Measurement

      NASA Technical Reports Server (NTRS)

      Davis, J. H.; Rives, C.

      1985-01-01

      Precise stable laser system determines coefficients of thermal expansion. Dual-beam interferometer arrangement monitors changes in sample length as function of temperature by following changes inoptical path lengths.

    4. Optimal Electric Utility Expansion

      SciTech Connect

      1989-10-10

      SAGE-WASP is designed to find the optimal generation expansion policy for an electrical utility system. New units can be automatically selected from a user-supplied list of expansion candidates which can include hydroelectric and pumped storage projects. The existing system is modeled. The calculational procedure takes into account user restrictions to limit generation configurations to an area of economic interest. The optimization program reports whether the restrictions acted as a constraint on the solution. All expansion configurations considered are required to pass a user supplied reliability criterion. The discount rate and escalation rate are treated separately for each expansion candidate and for each fuel type. All expenditures are separated into local and foreign accounts, and a weighting factor can be applied to foreign expenditures.

    5. Magnetic Clouds: Global and local expansion

      NASA Astrophysics Data System (ADS)

      Gulisano, Adriana; Demoulin, Pascal; Soledad Nakwacki, Ms Maria; Dasso, Sergio; Emilia Ruiz, Maria

      Magnetic clouds (MCs) are magnetized objects forming flux ropes, which are expelled from the Sun and travel through the heliosphere, transporting important amounts of energy, mass, magnetic flux, and magnetic helicity from the Sun to the interplanetary medium. To know the detailed dynamical evolution of MCs is very useful to improve the knowledge of solar processes, for instance from linking a transient solar source with its interplanetary manifestation. During its travel, and mainly due to the decrease of the total (magnetic plus thermal) pressure in the surrounding solar wind, MCs are objects in expansion. However, the detailed magnetic structure and the dynamical evolution of MCs is still not fully known. Even the identification of their boundaries is an open question in some cases. In a previous work we have shown that from onepoint observations of the bulk velocity profile, it is possible to infer the 'local' expansion rate for a given MC, i.e., the expansion rate while the MC is observed by the spacecraft. By the another hand, and from the comparison of sizes for different MCs observed at different heliodistances, it is possible to quantify an 'average' expansion law (i.e., a global expansion). In this work, in order to study the variability of the 'local' expansion with respect to the 'average' expansion of MCs during their travel, we present results and a comparison between both approaches. We make a detailed study of one-point observations (magnetic and bulk velocity) using a set of MCs and we get the 'local' expansion rate for each studied event. We compare the obtained 'local' expansion rates with the 'average' expansion law, and also with the expansion rates for the stationary solar wind.

    6. Mapping Impervious Surface Expansion using Medium-resolution Satellite Image Time Series: A Case Study in the Yangtze River Delta, China

      NASA Technical Reports Server (NTRS)

      Gao, Feng; DeColstoun, Eric Brown; Ma, Ronghua; Weng, Qihao; Masek, Jeffrey G.; Chen, Jin; Pan, Yaozhong; Song, Conghe

      2012-01-01

      Cities have been expanding rapidly worldwide, especially over the past few decades. Mapping the dynamic expansion of impervious surface in both space and time is essential for an improved understanding of the urbanization process, land-cover and land-use change, and their impacts on the environment. Landsat and other medium-resolution satellites provide the necessary spatial details and temporal frequency for mapping impervious surface expansion over the past four decades. Since the US Geological Survey opened the historical record of the Landsat image archive for free access in 2008, the decades-old bottleneck of data limitation has gone. Remote-sensing scientists are now rich with data, and the challenge is how to make best use of this precious resource. In this article, we develop an efficient algorithm to map the continuous expansion of impervious surface using a time series of four decades of medium-resolution satellite images. The algorithm is based on a supervised classification of the time-series image stack using a decision tree. Each imerpervious class represents urbanization starting in a different image. The algorithm also allows us to remove inconsistent training samples because impervious expansion is not reversible during the study period. The objective is to extract a time series of complete and consistent impervious surface maps from a corresponding times series of images collected from multiple sensors, and with a minimal amount of image preprocessing effort. The approach was tested in the lower Yangtze River Delta region, one of the fastest urban growth areas in China. Results from nearly four decades of medium-resolution satellite data from the Landsat Multispectral Scanner (MSS), Thematic Mapper (TM), Enhanced Thematic Mapper plus (ETM+) and China-Brazil Earth Resources Satellite (CBERS) show a consistent urbanization process that is consistent with economic development plans and policies. The time-series impervious spatial extent maps derived

    7. Earnings Returns to the British Education Expansion

      ERIC Educational Resources Information Center

      Devereux, Paul J.; Fan, Wen

      2011-01-01

      We study the effects of the large expansion in British educational attainment that took place for cohorts born between 1970 and 1975. Using the Quarterly Labour Force Survey, we find that the expansion caused men to increase education by about a year on average and gain about 8% higher wages; women obtained a slightly greater increase in education…

    8. Analysis of Performance Variation Using Query Expansion.

      ERIC Educational Resources Information Center

      Alemayehu, Nega

      2003-01-01

      Discussion of information retrieval performance evaluation focuses on a case study using a statistical repeated measures analysis of variance for testing the significance of factors, such as retrieval method and topic in retrieval performance variation. Analyses of the effect of query expansion on document ranking confirm that expansion affects…

    9. Analysis of Performance Variation Using Query Expansion.

      ERIC Educational Resources Information Center

      Alemayehu, Nega

      2003-01-01

      Discussion of information retrieval performance evaluation focuses on a case study using a statistical repeated measures analysis of variance for testing the significance of factors, such as retrieval method and topic in retrieval performance variation. Analyses of the effect of query expansion on document ranking confirm that expansion affects…

    10. Earnings Returns to the British Education Expansion

      ERIC Educational Resources Information Center

      Devereux, Paul J.; Fan, Wen

      2011-01-01

      We study the effects of the large expansion in British educational attainment that took place for cohorts born between 1970 and 1975. Using the Quarterly Labour Force Survey, we find that the expansion caused men to increase education by about a year on average and gain about 8% higher wages; women obtained a slightly greater increase in education…

    11. Series expansion of the modified Einstein Procedure

      Treesearch

      Seema Chandrakant Shah-Fairbank

      2009-01-01

      This study examines calculating total sediment discharge based on the Modified Einstein Procedure (MEP). A new procedure based on the Series Expansion of the Modified Einstein Procedure (SEMEP) has been developed. This procedure contains four main modifications to MEP. First, SEMEP solves the Einstein integrals quickly and accurately based on a series expansion. Next,...

    12. Expansion of a chromosomal repeat in Escherichia coli: roles of replication, repair, and recombination functions

      PubMed Central

      Poteete, Anthony R

      2009-01-01

      Background Previous studies of gene amplification in Escherichia coli have suggested that it occurs in two steps: duplication and expansion. Expansion is thought to result from homologous recombination between the repeated segments created by duplication. To explore the mechanism of expansion, a 7 kbp duplication in the chromosome containing a leaky mutant version of the lac operon was constructed, and its expansion into an amplified array was studied. Results Under selection for lac function, colonies bearing multiple copies of the mutant lac operon appeared at a constant rate of approximately 4 to 5 per million cells plated per day, on days two through seven after plating. Expansion was not seen in a recA strain; null mutations in recBCD and ruvC reduced the rate 100- and 10-fold, respectively; a ruvC recG double mutant reduced the rate 1000-fold. Expansion occurred at an increased rate in cells lacking dam, polA, rnhA, or uvrD functions. Null mutations of various other cellular recombination, repair, and stress response genes had little effect upon expansion. The red recombination genes of phage lambda could substitute for recBCD in mediating expansion. In the red-substituted cells, expansion was only partially dependent upon recA function. Conclusion These observations are consistent with the idea that the expansion step of gene amplification is closely related, mechanistically, to interchromosomal homologous recombination events. They additionally provide support for recently described models of RecA-independent Red-mediated recombination at replication forks. PMID:19236706

    13. Controlled Ecological Life Support Systems (CELSS) conceptual design option study

      NASA Technical Reports Server (NTRS)

      Oleson, Melvin; Olson, Richard L.

      1986-01-01

      Results are given of a study to explore options for the development of a Controlled Ecological Life Support System (CELSS) for a future Space Station. In addition, study results will benefit the design of other facilities such as the Life Sciences Research Facility, a ground-based CELSS demonstrator, and will be useful in planning longer range missions such as a lunar base or manned Mars mission. The objectives were to develop weight and cost estimates for one CELSS module selected from a set of preliminary plant growth unit (PGU) design options. Eleven Space Station CELSS module conceptual PGU designs were reviewed, components and subsystems identified and a sensitivity analysis performed. Areas where insufficient data is available were identified and divided into the categories of biological research, engineering research, and technology development. Topics which receive significant attention are lighting systems for the PGU, the use of automation within the CELSS system, and electric power requirements. Other areas examined include plant harvesting and processing, crop mix analysis, air circulation and atmosphere contaminant flow subsystems, thermal control considerations, utility routing including accessibility and maintenance, and nutrient subsystem design.

    14. Lunar Portable Life Support System Heat Rejection Study

      NASA Technical Reports Server (NTRS)

      Conger, Bruce; Sompayrac,Robert G.; Trevino, Luis A.; Bue, Grant C.

      2009-01-01

      Performing extravehicular activity (EVA) at various locations of the lunar surface presents thermal challenges that exceed those experienced in space flight to date. The lunar Portable Life Support System (PLSS) cooling unit must maintain thermal conditions within the space suit and reject heat loads generated by the crewmember and the PLSS equipment. The amount of cooling required varies based on the lunar location and terrain due to the heat transferred between the suit and its surroundings. A study has been completed which investigated the resources required to provide cooling under various lunar conditions, assuming three different thermal technology categories: 1. Spacesuit Water Membrane Evaporator (SWME) 2. Subcooled Phase Change Material (SPCM) 3. Radiators with and without heat pumps Results from the study are presented that show mass and power impacts on the cooling system as a function of the location and terrain on the lunar surface. Resources (cooling equipment mass and consumables) are greater at the equator and inside sunlit craters due to the additional heat loads on the cooling system. While radiator and SPCM technologies require minimal consumables, they come with carry-weight penalties and have limitations. A wider investigation is recommended to determine if these penalties and limitations are offset by the savings in consumables.

    15. Ex vivo expansion of human hematopoietic stem and progenitor cells

      PubMed Central

      Dahlberg, Ann; Delaney, Colleen

      2011-01-01

      Despite progress in our understanding of the growth factors that support the progressive maturation of the various cell lineages of the hematopoietic system, less is known about factors that govern the self-renewal of hematopoietic stem and progenitor cells (HSPCs), and our ability to expand human HSPC numbers ex vivo remains limited. Interest in stem cell expansion has been heightened by the increasing importance of HSCs in the treatment of both malignant and nonmalignant diseases, as well as their use in gene therapy. To date, most attempts to ex vivo expand HSPCs have used hematopoietic growth factors but have not achieved clinically relevant effects. More recent approaches, including our studies in which activation of the Notch signaling pathway has enabled a clinically relevant ex vivo expansion of HSPCs, have led to renewed interest in this arena. Here we briefly review early attempts at ex vivo expansion by cytokine stimulation followed by an examination of our studies investigating the role of Notch signaling in HSPC self-renewal. We will also review other recently developed approaches for ex vivo expansion, primarily focused on the more extensively studied cord blood–derived stem cell. Finally, we discuss some of the challenges still facing this field. PMID:21436068

    16. Effects of urbanization expansion on landscape pattern and region ecological risk in Chinese coastal city: a case study of Yantai city.

      PubMed

      Zhou, Di; Shi, Ping; Wu, Xiaoqing; Ma, Jinwei; Yu, Junbao

      2014-01-01

      Applied with remote sensing, GIS, and mathematical statistics, the spatial-temporal evolution characteristics of urbanization expansion of Yantai city from 1974 to 2009 was studied. Based on landscape pattern metrics and ecological risk index, the landscape ecological risk from the landscape pattern dynamics was evaluated. The results showed that the area of urban land increased by 189.77 km(2) with average expansion area of 5.42 km(2) y(-1) from 1974 to 2009. The urbanization intensity index during 2004-2009 was 3.92 times of that during 1974-1990. The land use types of urban land and farmland changed greatly. The changes of landscape pattern metrics for land use patterns indicated that the intensity of human activities had strengthened gradually in study period. The landscape ecological risk pattern of Yantai city shaped half-round rings along the coastline. The ecological risk index decreased with increase of the distance to the coastline. The ratio of high ecological risk to subhigh ecological risk zones in 2009 was 2.23 times of that in 1990. The significant linear relationship of urbanization intensity index and regional ecological risk indicated that the anthropological economic activities were decisive factors for sustainable development of costal ecological environment.

    17. Effects of Urbanization Expansion on Landscape Pattern and Region Ecological Risk in Chinese Coastal City: A Case Study of Yantai City

      PubMed Central

      Zhou, Di; Shi, Ping; Wu, Xiaoqing; Ma, Jinwei

      2014-01-01

      Applied with remote sensing, GIS, and mathematical statistics, the spatial-temporal evolution characteristics of urbanization expansion of Yantai city from 1974 to 2009 was studied. Based on landscape pattern metrics and ecological risk index, the landscape ecological risk from the landscape pattern dynamics was evaluated. The results showed that the area of urban land increased by 189.77 km2 with average expansion area of 5.42 km2 y−1 from 1974 to 2009. The urbanization intensity index during 2004–2009 was 3.92 times of that during 1974–1990. The land use types of urban land and farmland changed greatly. The changes of landscape pattern metrics for land use patterns indicated that the intensity of human activities had strengthened gradually in study period. The landscape ecological risk pattern of Yantai city shaped half-round rings along the coastline. The ecological risk index decreased with increase of the distance to the coastline. The ratio of high ecological risk to subhigh ecological risk zones in 2009 was 2.23 times of that in 1990. The significant linear relationship of urbanization intensity index and regional ecological risk indicated that the anthropological economic activities were decisive factors for sustainable development of costal ecological environment. PMID:24983003

    18. Lattice-structures and constructs with designed thermal expansion coefficients

      SciTech Connect

      Spadaccini, Christopher; Hopkins, Jonathan

      2014-10-28

      A thermal expansion-managed lattice structure having a plurality of unit cells each having flexure bearing-mounted tabs supported on a base and actuated by thermal expansion of an actuator having a thermal expansion coefficient greater than the base and arranged so that the tab is inwardly displaced into a base cavity. The flexure bearing-mounted tabs are connected to other flexure-bearing-mounted tabs of adjacent unit cells so that the adjacent unit cells are spaced from each other to accommodate thermal expansion of individual unit cells while maintaining a desired bulk thermal expansion coefficient of the lattice structure as a whole.

    19. Application of Campus Instructional Support: Two Case Studies

      ERIC Educational Resources Information Center

      Clauss-Ehlers, Caroline S.; Pasquerella, Lynn

      2017-01-01

      Purpose: The purpose of this paper is to demonstrate how instructional support is a critical tool to promote the use of technology in research and teaching. A Campus-Wide Collaborative Model of Technological Instructional Support (CCMTIS) is presented that incorporates: integration of technology across campus; technical assistance; allocation of…

    20. Comparative Study of Student Support Services of UKOU and SLOU

      ERIC Educational Resources Information Center

      Gujjar, Aijaz Ahmed; Choudhry, Bushra Naoreen; Choudhry, Amtul Hafeez

      2008-01-01

      This paper attempts to compare the availability, quality, similarities and differences of students' support services in United Kingdom Open University (UKOU) and Sri Lanka Open University (SLOU) and also to identify and enlist the deficiencies that SLOU students are facing in the student support services. To get the desired end four hundred…

    1. Workplace rehabilitation and supportive conditions at work: a prospective study.

      PubMed

      Ahlstrom, Linda; Hagberg, Mats; Dellve, Lotta

      2013-06-01

      To investigate the impact of rehabilitation measures on work ability and return to work (RTW), specifically the association between workplace rehabilitation/supportive conditions at work and work ability and RTW over time, among women on long-term sick leave. Questionnaire data were collected (baseline, 6 and 12 months) from a cohort of women (n = 324). Linear mixed models were used for longitudinal analysis of the repeated measurements of work ability index (WAI), work ability score and working degree. These analyses were performed with different models; the explanatory variables for each model were workplace rehabilitation, supportive conditions at work and time. The individuals provided with workplace rehabilitation and supportive conditions (e.g. influence at work, possibilities for development, degree of freedom at work, meaning of work, quality of leadership, social support, sense of community and work satisfaction) had significantly increased WAI and work ability score over time. These individuals scored higher work ability compared to those individuals having workplace rehabilitation without supportive conditions, or neither. Additionally, among the individuals provided with workplace rehabilitation and supportive conditions, working degree increased significantly more over time compared to those individuals with no workplace rehabilitation and no supportive conditions. The results highlight the importance of integrating workplace rehabilitation with supportive conditions at work in order to increase work ability and improve the RTW process for women on long-term sick leave.

    2. Structural, negative thermal expansion and photocatalytic properties of ZrV{sub 2}O{sub 7}: a comparative study between fibers and powders

      SciTech Connect

      Liu, Qinqin; Yang, Juan; Rong, Xiaoqing; Sun, Xiujuan; Cheng, Xiaonong; Tang, Hua; Li, Haohua

      2014-10-15

      Novel ZrV{sub 2}O{sub 7} microfibers with diameters about 1–3 μm were synthesized using a sol–gel technique. For comparison, ZrV{sub 2}O{sub 7} powders were prepared by the same method. The resultant structures were studied by X-ray diffraction, field-emission scanning electron microscopy and transmission electron microscopy. The results indicated that both the pure ZrV{sub 2}O{sub 7} microfibers and powders could be synthesized by the sol–gel technique. The thermal expansion property of the as-prepared ZrV{sub 2}O{sub 7} microfibers and powders was characterized by a thermal mechanical analyzer, both the fibers with cylindrical morphology and irregular powders with average size between 100 and 200 nm showed negative thermal expansion between 150 °C and 600 °C. The photocatalytic activity of the microfibers was compared to that of powders under UV radiations. The band gap of ZrV{sub 2}O{sub 7} microfibers decreased and its absorption edge exhibited red shift. The microfibers also had a higher surface area compared with the powders, resulting in considerably higher photocatalytic characteristics. The large surface area and the enhanced photocatalytic activity of the ZrV{sub 2}O{sub 7} microfibers also offer potential applications in sensors and inorganic ion exchangers. - Graphical abstract: (a and c) SEM photos of ZrV{sub 2}O{sub 7} powders and fibers. (b and d) TEM images of ZrV{sub 2}O{sub 7} powders and fibers. (e) Thermal expansion curves of ZrV{sub 2}O{sub 7} powders and fibers. (f) Degradation curves of ZrV{sub 2}O{sub 7} powders and ZrV{sub 2}O{sub 7} fibers. - Highlights: • Novel ZrV{sub 2}O{sub 7} fibers could be synthesized using sol–gel technique. • ZrV{sub 2}O{sub 7} powders with irregular shape are also prepared for comparison. • Both ZrV{sub 2}O{sub 7} microfibers and powders exhibit negative thermal expansion property. • ZrV{sub 2}O{sub 7} microfibers show outstanding photocatalytic activity under UV irradiation. • This synthesis

    3. Surface response methodology for the study of supported membrane formation.

      PubMed

      Rossi, Claire; Briand, Elisabeth; Parot, Pierre; Odorico, Michael; Chopineau, Joël

      2007-07-05

      We report on the investigations of the formation of the tethered lipid bilayer by vesicle deposition on amine-functionalized surfaces. The tethered bilayer was created by the deposition of egg-PC vesicles containing 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-poly-(ethyleneglycol)-N-hydroxysuccinimide as anchoring molecules on an amine-coated surface. This approach is an easy route for the formation of a biomimetic-supported membrane. A Doelhert experimental design was applied to determine the conditions leading to the formation of a continuous and defect-free tethered bilayer on different surfaces (gold and glass). Doehlert designs allow modeling of the experimental responses by second-order polynomial equations as a function of experimental factors. Four factors expected to influence bilayer formation were studied: the lipid concentration in the vesicle suspension, the mass percentage of anchoring molecules in the vesicles, the contact time between the vesicles and the surface, and the resting time of the membrane after buffer rinse. The optimization of the membrane preparation parameters was achieved by monitoring lipid assembly formation using surface plasmon resonance spectroscopy on gold and by fluorescence recovery after photobleaching on glass. Three characteristic responses were systematically measured: the bilayer thickness, the lipid diffusion coefficient, and the lipid mobile fraction. The simultaneous inspection of the three characteristics revealed that a restricted experimental domain leads to properties that are in accordance with a bilayer presence. The factors of this domain are a lipid concentration from 0.1 to 1 mg/mL, 4-8% of anchoring molecules in the vesicles, 1-4 h of contact time between vesicles and surface, and 21-24 h of resting time after buffer rinse. Under these conditions, a membrane having a lipid mass per surface between 545 +/- 5 and 590 +/- 10 ng/cm2, a diffusion coefficient of between 2.5 +/- 0.3 x 10(-8) and 3.60 +/- 0.5 x

    4. LPS-TLR4 Pathway Mediates Ductular Cell Expansion in Alcoholic Hepatitis

      PubMed Central

      Odena, Gemma; Chen, Jiegen; Lozano, Juan Jose; Altamirano, Jose; Rodrigo-Torres, Daniel; Affo, Silvia; Morales-Ibanez, Oriol; Matsushita, Hiroshi; Zou, Jian; Dumitru, Raluca; Caballeria, Juan; Gines, Pere; Arroyo, Vicente; You, Min; Rautou, Pierre-Emmanuel; Valla, Dominique; Crews, Fulton; Seki, Ekihiro; Sancho-Bru, Pau; Bataller, Ramon

      2016-01-01

      Alcoholic hepatitis (AH) is the most severe form of alcoholic liver disease for which there are no effective therapies. Patients with AH show impaired hepatocyte proliferation, expansion of inefficient ductular cells and high lipopolysaccharide (LPS) levels. It is unknown whether LPS mediates ductular cell expansion. We performed transcriptome studies and identified keratin 23 (KRT23) as a new ductular cell marker. KRT23 expression correlated with mortality and LPS serum levels. LPS-TLR4 pathway role in ductular cell expansion was assessed in human and mouse progenitor cells, liver slices and liver injured TLR4 KO mice. In AH patients, ductular cell expansion correlated with portal hypertension and collagen expression. Functional studies in ductular cells showed that KRT23 regulates collagen expression. These results support a role for LPS-TLR4 pathway in promoting ductular reaction in AH. Maneuvers aimed at decreasing LPS serum levels in AH patients could have beneficial effects by preventing ductular reaction development. PMID:27752144

    5. An Arabidopsis kinase cascade influences auxin-responsive cell expansion.

      PubMed

      Enders, Tara A; Frick, Elizabeth M; Strader, Lucia C

      2017-10-01

      Mitogen-activated protein kinase (MPK) cascades are conserved mechanisms of signal transduction across eukaryotes. Despite the importance of MPK proteins in signaling events, specific roles for many Arabidopsis MPK proteins remain unknown. Multiple studies have suggested roles for MPK signaling in a variety of auxin-related processes. To identify MPK proteins with roles in auxin response, we screened mpk insertional alleles and identified mpk1-1 as a mutant that displays hypersensitivity in auxin-responsive cell expansion assays. Further, mutants defective in the upstream MAP kinase kinase MKK3 also display hypersensitivity in auxin-responsive cell expansion assays, suggesting that this MPK cascade affects auxin-influenced cell expansion. We found that MPK1 interacts with and phosphorylates ROP BINDING PROTEIN KINASE 1 (RBK1), a protein kinase that interacts with members of the Rho-like GTPases from Plants (ROP) small GTPase family. Similar to mpk1-1 and mkk3-1 mutants, rbk1 insertional mutants display auxin hypersensitivity, consistent with a possible role for RBK1 downstream of MPK1 in influencing auxin-responsive cell expansion. We found that RBK1 directly phosphorylates ROP4 and ROP6, supporting the possibility that RBK1 effects on auxin-responsive cell expansion are mediated through phosphorylation-dependent modulation of ROP activity. Our data suggest a MKK3 • MPK1 • RBK1 phosphorylation cascade that may provide a dynamic module for altering cell expansion. © 2017 The Authors The Plant Journal © 2017 John Wiley & Sons Ltd.

    6. In Support of a National Treatment Evaluation Study.

      PubMed

      Brown, Barry S; Flynn, Patrick M

      2015-01-01

      Argument is made for the importance of conducting a national treatment evaluation to permit understanding of the nature and effectiveness of typical treatment programming. Only through such study can we hope to learn areas of success and failure of normative programming relative to population characteristics and treatment strategies, and the extent to which research-based initiatives have been adopted by the field. That information is central to efforts to draw up a research agenda appropriate to the needs of clients and the staffs responsible for their treatment, and to clarify and respond to gaps in the application of potentially useful treatment components. In spite of such need, our understanding of typical treatment programming and of its effectiveness is based on data collected from a treatment cohort of 20 years ago, although patterns of drug use, characteristics of clients, and the treatment components available have all undergone substantial change. The responsibility taken to provide such information to the field, once seen as a central task of research, needs to be reasserted to strengthen and support our treatment efforts.

    7. Model catalytic oxidation studies using supported monometallic and heterobimetallic oxides

      SciTech Connect

      Ekerdt, J.G.

      1992-02-03

      This research program is directed toward a more fundamental understanding of the effects of catalyst composition and structure on the catalytic properties of metal oxides. Metal oxide catalysts play an important role in many reactions bearing on the chemical aspects of energy processes. Metal oxides are the catalysts for water-gas shift reactions, methanol and higher alcohol synthesis, isosynthesis, selective catalytic reduction of nitric oxides, and oxidation of hydrocarbons. A key limitation to developing insight into how oxides function in catalytic reactions is in not having precise information of the surface composition under reaction conditions. To address this problem we have prepared oxide systems that can be used to study cation-cation effects and the role of bridging (-O-) and/or terminal (=O) surface oxygen anion ligands in a systematic fashion. Since many oxide catalyst systems involve mixtures of oxides, we selected a model system that would permit us to examine the role of each cation separately and in pairwise combinations. Organometallic molybdenum and tungsten complexes were proposed for use, to prepare model systems consisting of isolated monomeric cations, isolated monometallic dimers and isolated bimetallic dimers supported on silica and alumina. The monometallic and bimetallic dimers were to be used as models of more complex mixed- oxide catalysts. Our current program was to develop the systems and use them in model oxidation reactions.

    8. Controlled environment life support system: Growth studies with potatoes

      NASA Technical Reports Server (NTRS)

      Tibbitts, T. W.; Wheeler, R. M.

      1986-01-01

      Results of experiments conducted to maximize the productivity of potatoes grown under controlled environmental conditions are discussed. A variety of parameters is examined which affect potato growth, specifically, photoperiod, light intensity, temperature, nitrogen nutrition, carbon dioxide concentration and culture techniques. These experiments were conducted using five different cultivars, Russet Burbank, Norchip, Superior, Kennebec and Norland. To achieve high productivity, three specific objectives were explored: (1) to develop effective cultural procedures, (2) to determine the most effective photoperiod and (3) to develop a mist culture system. It is felt that the productivity obtained in this study is below the maximum that can be obtained. High irradiance levels coupled with tuber-promoting conditions such as cooler temperatures, increased CO2 levels and lowered nitrogen concentrations should allow increases in tuber production. Tuberization appears to be accelerated by short daylengths although final yields are not increased. Mist culture techniques have not yet produced fully developed tubers. The use of supporting media and alteration of the nitrogen content of the mist solution are being explored as a way to allow tubers to develop to maturity.

    9. Study of Alginate-Supported Ionic Liquid and Pd Catalysts

      PubMed Central

      Jouannin, Claire; Vincent, Chloë; Dez, Isabelle; Gaumont, Annie-Claude; Vincent, Thierry; Guibal, Eric

      2012-01-01

      New catalytic materials, based on palladium immobilized in ionic liquid supported on alginate, were elaborated. Alginate was associated with gelatin for the immobilization of ionic liquids (ILs) and the binding of palladium. These catalytic materials were designed in the form of highly porous monoliths (HPMs), in order to be used in a column reactor. The catalytic materials were tested for the hydrogenation of 4-nitroaniline (4-NA) in the presence of formic acid as hydrogen donor. The different parameters for the elaboration of the catalytic materials were studied and their impact analyzed in terms of microstructures, palladium sorption properties and catalytic performances. The characteristics of the biopolymer (proportion of β-D-mannuronic acid (M) and α-L-guluronic acid (G) in the biopolymer defined by the M/G ratio), the concentration of the porogen agent, and the type of coagulating agent significantly influenced catalytic performances. The freezing temperature had a significant impact on structural properties, but hardly affected the catalytic rate. Cellulose fibers were incorporated as mechanical strengthener into the catalytic materials, and allowed to enhance mechanical properties and catalytic efficiency but required increasing the amount of hydrogen donor for catalysis.

    10. Effects of biaxial strain on the improper multiferroicity in h–LuFeO3 films studied using the restrained thermal expansion method

      DOE PAGES

      Sinha, Kishan; Zhang, Yubo; Jiang, Xuanyuan; ...

      2017-03-14

      Elastic strain is potentially an important approach in tuning the properties of the improperly multiferroic hexagonal ferrites, the details of which have however been elusive due to the experimental difficulties. Employing the method of restrained thermal expansion, we have studied the effect of isothermal biaxial strain in the basal plane of h-LuFeO3 (001) films. The results indicate that a compressive biaxial strain significantly enhances the K3 structural distortion (the order parameter of the improper ferroelectricity), and the effect is larger at higher temperatures. The compressive biaxial strain and the enhanced K3 structural distortion together, cause an increase in the electricmore » polarization and a reduction in the canting of the weak ferromagnetic moments in h-LuFeO3, according to our first principle calculations. These findings are important for understanding the strain effect as well as the coupling between the lattice and the improper multiferroicity in h-LuFeO3. Finally, the experimental elucidation of the strain effect in h-LuFeO3 films also suggests that the restrained thermal expansion can be a viable method to unravel the strain effect in many other thin film materials.« less

    11. Effects of biaxial strain on the improper multiferroicity in h -LuFe O3 films studied using the restrained thermal expansion method

      NASA Astrophysics Data System (ADS)

      Sinha, Kishan; Zhang, Yubo; Jiang, Xuanyuan; Wang, Hongwei; Wang, Xiao; Zhang, Xiaozhe; Ryan, Philip J.; Kim, Jong-Woo; Bowlan, John; Yarotski, Dmitry A.; Li, Yuelin; DiChiara, Anthony D.; Cheng, Xuemei; Wu, Xifan; Xu, Xiaoshan

      2017-03-01

      Elastic strain is potentially an important approach in tuning the properties of the improperly multiferroic hexagonal ferrites, the details of which, however, have been elusive due to experimental difficulties. Employing the method of restrained thermal expansion, we have studied the effect of isothermal biaxial strain in the basal plane of h -LuFe O3 (001) films. The results indicate that a compressive biaxial strain significantly enhances the K3 structural distortion (the order parameter of the improper ferroelectricity), and the effect is larger at higher temperatures. The compressive biaxial strain and the enhanced K3 structural distortion together cause an increase in the electric polarization and a reduction in the canting of the weak ferromagnetic moments in h -LuFe O3 , according to our first principles calculations. These findings are important for understanding the strain effect as well as the coupling between the lattice and the improper multiferroicity in h -LuFe O3 . The experimental elucidation of the strain effect in h -LuFe O3 films also suggests that the restrained thermal expansion can be a viable method to unravel the strain effect in many other thin film materials.

    12. SDU 6 MODELING STUDY TO SUPPORT DESIGN DEVELOPMENT

      SciTech Connect

      Smith, F.

      2012-05-02

      In response to Technical Task Request (TTR) HLW-SSF-TTR-2012-0017 (1), SRNL performed modeling studies to evaluate alternative design features for the 32 million gallon Saltstone Disposal Unit (SDU) referred to as SDU 6. This initial modeling study was intended to assess the performance of major components of the structure that are most significant to the PA. Information provided by the modeling will support the development of a SDU 6 Preliminary Design Model and Recommendation Report to be written by SRR Closure and Waste Disposal Authority. Key inputs and assumptions for the modeling were provided to SRNL in SRR-SPT-2011-00113 (2). A table reiterates the base case and four sensitivity case studies requested in this reference. In general, as shown in Table 4, when compared to Vault 2 Case A, the Base Case SDU 6 design produced higher peak fluxes to the water table during the 10,000 year period of analysis but lower peak fluxes within a 15,000 to 20,000 time frame. SDU 6 will contain approximately ten times the inventory of a single Vault 2 and the SDU 6 footprint is comparable to that of a group of four Vault 2 disposal units. Therefore, the radionuclide flux from SDU 6 and that from a single Vault 2 are not directly comparable. A more direct comparison would be to compare the maximum dose obtained at the 100 m boundary from the seven SDU's that will replace the 64 FDC's analyzed in the 2009 PA. This analysis will be performed in the next set of calculations planned for SDU design evaluation. Aquifer transport and dose calculations were not intended to be part of this initial scoping study. However, results from this study do indicate that replacement of the FDC design with SDU would not yield significantly higher peak doses. If the thickness of the SDU 6 floor is increased, peak doses would not occur during the 10,000 year period of analysis.

    13. Prescribed burning supports grassland biodiversity - A multi-species study

      NASA Astrophysics Data System (ADS)

      Valkó, Orsolya; Deák, Balázs; Magura, Tibor; Török, Péter; Kelemen, András; Tóth, Katalin; Horváth, Roland; Nagy, Dávid; Debnár, Zsuzsanna; Zsigrai, György; Kapocsi, István; Tóthmérész, Béla

      2017-04-01

      During ancient times, fire was an important factor shaping European landscapes. Nowadays, prescribed burning can be one of the most effective conservation tools for the management of open landscapes, controlling dominant species, reducing accumulated litter or decreasing wildfire risk. In a prescribed burning experiment, we studied the effects of fire on dry alkaline grasslands. We tested whether autumn prescribed burning can be an alternative conservation measure in these grasslands. We selected six sites in Hungary: in three sites, prescribed burning was applied in November 2011, while three sites remained unburnt. We studied the effects of fire on soil characteristics, plant biomass and on the vegetation and arthropod assemblages (isopods, spiders, ground beetles and rove beetles). Soluble salt content increased significantly in the burnt sites, but soil pH, organic matter, potassium and phosphorous did not change. We found that prescribed fire had several positive effects from the nature conservation viewpoint. Diversity and the number of flowering shoots were higher, and the cover of the dominant grass was lower in the burnt sites. Graminoid biomass was lower, while total, green and forb biomass were higher in the burnt plots compared to the control ones. Our findings suggest that prescribed burning fire did not harm arthropods; species-level analyses showed that out of the most abundant invertebrate species, the abundance of ten was not affected, one decreased and one increased after burning. Our findings highlight that mosaic prescribed fire is a viable management tool in open landscapes, because it supports plant diversity and does not threaten arthropods.

    14. Chemical mixing study for the Hanford TWRS Supporting facilities (U)

      SciTech Connect

      Heal, D.W.; Brantley, W.M.

      1996-09-03

      This Engineering Calculation addresses consequences of mixing any two hazardous chemicals contained in the same section of TWRS supporting facilities, as screened in accordance with `Westinghouse Savannah River Company Engineering and Construction Services Division Guidelines and Methods.`

    15. Study of space shuttle environmental control and life support problems

      NASA Technical Reports Server (NTRS)

      Dibble, K. P.; Riley, F. E.

      1971-01-01

      Four problem areas were treated: (1) cargo module environmental control and life support systems; (2) space shuttle/space station interfaces; (3) thermal control considerations for payloads; and (4) feasibility of improving system reusability.

    16. 46 CFR 56.35-10 - Nonmetallic expansion joints (replaces 119.5.1).

      Code of Federal Regulations, 2013 CFR

      2013-10-01

      ... 46 Shipping 2 2013-10-01 2013-10-01 false Nonmetallic expansion joints (replaces 119.5.1). 56.35... ENGINEERING PIPING SYSTEMS AND APPURTENANCES Expansion, Flexibility and Supports § 56.35-10 Nonmetallic expansion joints (replaces 119.5.1). (a) Nonmetallic expansion joints certified in accordance with subpart...

    17. 46 CFR 56.35-10 - Nonmetallic expansion joints (replaces 119.5.1).

      Code of Federal Regulations, 2010 CFR

      2010-10-01

      ... 46 Shipping 2 2010-10-01 2010-10-01 false Nonmetallic expansion joints (replaces 119.5.1). 56.35... ENGINEERING PIPING SYSTEMS AND APPURTENANCES Expansion, Flexibility and Supports § 56.35-10 Nonmetallic expansion joints (replaces 119.5.1). (a) Nonmetallic expansion joints certified in accordance with subpart...

    18. 46 CFR 56.35-15 - Metallic expansion joints (replaces 119.5.1).

      Code of Federal Regulations, 2010 CFR

      2010-10-01

      ... 46 Shipping 2 2010-10-01 2010-10-01 false Metallic expansion joints (replaces 119.5.1). 56.35-15... PIPING SYSTEMS AND APPURTENANCES Expansion, Flexibility and Supports § 56.35-15 Metallic expansion joints (replaces 119.5.1). (a) Metallic expansion joints certified in accordance with subpart 50.25 of this...

    19. 46 CFR 56.35-15 - Metallic expansion joints (replaces 119.5.1).

      Code of Federal Regulations, 2014 CFR

      2014-10-01

      ... 46 Shipping 2 2014-10-01 2014-10-01 false Metallic expansion joints (replaces 119.5.1). 56.35-15... PIPING SYSTEMS AND APPURTENANCES Expansion, Flexibility and Supports § 56.35-15 Metallic expansion joints (replaces 119.5.1). (a) Metallic expansion joints certified in accordance with subpart 50.25 of this...

    20. 46 CFR 56.35-15 - Metallic expansion joints (replaces 119.5.1).

      Code of Federal Regulations, 2013 CFR

      2013-10-01

      ... 46 Shipping 2 2013-10-01 2013-10-01 false Metallic expansion joints (replaces 119.5.1). 56.35-15... PIPING SYSTEMS AND APPURTENANCES Expansion, Flexibility and Supports § 56.35-15 Metallic expansion joints (replaces 119.5.1). (a) Metallic expansion joints certified in accordance with subpart 50.25 of this...

    1. 46 CFR 56.35-15 - Metallic expansion joints (replaces 119.5.1).

      Code of Federal Regulations, 2012 CFR

      2012-10-01

      ... 46 Shipping 2 2012-10-01 2012-10-01 false Metallic expansion joints (replaces 119.5.1). 56.35-15... PIPING SYSTEMS AND APPURTENANCES Expansion, Flexibility and Supports § 56.35-15 Metallic expansion joints (replaces 119.5.1). (a) Metallic expansion joints certified in accordance with subpart 50.25 of this...

    2. 46 CFR 56.35-15 - Metallic expansion joints (replaces 119.5.1).

      Code of Federal Regulations, 2011 CFR

      2011-10-01

      ... 46 Shipping 2 2011-10-01 2011-10-01 false Metallic expansion joints (replaces 119.5.1). 56.35-15... PIPING SYSTEMS AND APPURTENANCES Expansion, Flexibility and Supports § 56.35-15 Metallic expansion joints (replaces 119.5.1). (a) Metallic expansion joints certified in accordance with subpart 50.25 of this...

    3. 46 CFR 56.35-10 - Nonmetallic expansion joints (replaces 119.5.1).

      Code of Federal Regulations, 2014 CFR

      2014-10-01

      ... 46 Shipping 2 2014-10-01 2014-10-01 false Nonmetallic expansion joints (replaces 119.5.1). 56.35... ENGINEERING PIPING SYSTEMS AND APPURTENANCES Expansion, Flexibility and Supports § 56.35-10 Nonmetallic expansion joints (replaces 119.5.1). (a) Nonmetallic expansion joints certified in accordance with subpart...

    4. 46 CFR 56.35-10 - Nonmetallic expansion joints (replaces 119.5.1).

      Code of Federal Regulations, 2012 CFR

      2012-10-01

      ... 46 Shipping 2 2012-10-01 2012-10-01 false Nonmetallic expansion joints (replaces 119.5.1). 56.35... ENGINEERING PIPING SYSTEMS AND APPURTENANCES Expansion, Flexibility and Supports § 56.35-10 Nonmetallic expansion joints (replaces 119.5.1). (a) Nonmetallic expansion joints certified in accordance with subpart...

    5. 46 CFR 56.35-10 - Nonmetallic expansion joints (replaces 119.5.1).

      Code of Federal Regulations, 2011 CFR

      2011-10-01

      ... 46 Shipping 2 2011-10-01 2011-10-01 false Nonmetallic expansion joints (replaces 119.5.1). 56.35... ENGINEERING PIPING SYSTEMS AND APPURTENANCES Expansion, Flexibility and Supports § 56.35-10 Nonmetallic expansion joints (replaces 119.5.1). (a) Nonmetallic expansion joints certified in accordance with subpart...

    6. Virial Expansion Bounds

      NASA Astrophysics Data System (ADS)

      Tate, Stephen James

      2013-10-01

      In the 1960s, the technique of using cluster expansion bounds in order to achieve bounds on the virial expansion was developed by Lebowitz and Penrose (J. Math. Phys. 5:841, 1964) and Ruelle (Statistical Mechanics: Rigorous Results. Benjamin, Elmsford, 1969). This technique is generalised to more recent cluster expansion bounds by Poghosyan and Ueltschi (J. Math. Phys. 50:053509, 2009), which are related to the work of Procacci (J. Stat. Phys. 129:171, 2007) and the tree-graph identity, detailed by Brydges (Phénomènes Critiques, Systèmes Aléatoires, Théories de Jauge. Les Houches 1984, pp. 129-183, 1986). The bounds achieved by Lebowitz and Penrose can also be sharpened by doing the actual optimisation and achieving expressions in terms of the Lambert W-function. The different bound from the cluster expansion shows some improvements for bounds on the convergence of the virial expansion in the case of positive potentials, which are allowed to have a hard core.

    7. Study of space shuttle EVA/IVA support requirements. Volume 5: Requirements study for space shuttle emergency 4 support

      NASA Technical Reports Server (NTRS)

      Copeland, R. J.; Cox, R. L.

      1973-01-01

      The requirements for space shuttle emergency intravehicular activity support equipment are discussed. The potential emergencies considered are: (1) contaminated atmosphere, (2) accidental decompression, (3) inability to re-enter, and (4) crewman stranded. Contingency life support systems are described and the effectiveness of each emergency procedure is analyzed.

    8. Convex relaxations for gas expansion planning

      SciTech Connect

      Borraz-Sanchez, Conrado; Bent, Russell Whitford; Backhaus, Scott N.; Hijazi, Hassan; Van Hentenryck, Pascal

      2016-01-01

      Expansion of natural gas networks is a critical process involving substantial capital expenditures with complex decision-support requirements. Here, given the non-convex nature of gas transmission constraints, global optimality and infeasibility guarantees can only be offered by global optimisation approaches. Unfortunately, state-of-the-art global optimisation solvers are unable to scale up to real-world size instances. In this study, we present a convex mixed-integer second-order cone relaxation for the gas expansion planning problem under steady-state conditions. The underlying model offers tight lower bounds with high computational efficiency. In addition, the optimal solution of the relaxation can often be used to derive high-quality solutions to the original problem, leading to provably tight optimality gaps and, in some cases, global optimal solutions. The convex relaxation is based on a few key ideas, including the introduction of flux direction variables, exact McCormick relaxations, on/off constraints, and integer cuts. Numerical experiments are conducted on the traditional Belgian gas network, as well as other real larger networks. The results demonstrate both the accuracy and computational speed of the relaxation and its ability to produce high-quality solution

    9. Convex relaxations for gas expansion planning

      DOE PAGES

      Borraz-Sanchez, Conrado; Bent, Russell Whitford; Backhaus, Scott N.; ...

      2016-01-01

      Expansion of natural gas networks is a critical process involving substantial capital expenditures with complex decision-support requirements. Here, given the non-convex nature of gas transmission constraints, global optimality and infeasibility guarantees can only be offered by global optimisation approaches. Unfortunately, state-of-the-art global optimisation solvers are unable to scale up to real-world size instances. In this study, we present a convex mixed-integer second-order cone relaxation for the gas expansion planning problem under steady-state conditions. The underlying model offers tight lower bounds with high computational efficiency. In addition, the optimal solution of the relaxation can often be used to derive high-quality solutionsmore » to the original problem, leading to provably tight optimality gaps and, in some cases, global optimal solutions. The convex relaxation is based on a few key ideas, including the introduction of flux direction variables, exact McCormick relaxations, on/off constraints, and integer cuts. Numerical experiments are conducted on the traditional Belgian gas network, as well as other real larger networks. The results demonstrate both the accuracy and computational speed of the relaxation and its ability to produce high-quality solution« less

    10. Expansion of Einstein-Yang-Mills amplitude

      NASA Astrophysics Data System (ADS)

      Fu, Chih-Hao; Du, Yi-Jian; Huang, Rijun; Feng, Bo

      2017-09-01

      In this paper, we study from various perspectives the expansion of tree level single trace Einstein-Yang-Mills amplitudes into linear combination of color-ordered Yang-Mills amplitudes. By applying the gauge invariance principle, a programable recursive construction is devised to expand EYM amplitude with arbitrary number of gravitons into EYM amplitudes with fewer gravitons. Based on this recursive technique we write down the complete expansion of any single trace EYM amplitude in the basis of color-order Yang-Mills amplitude. As a byproduct, an algorithm for constructing a polynomial form of the BCJ numerator for Yang-Mills amplitudes is also outlined in this paper. In addition, by applying BCFW recursion relation we show how to arrive at the same EYM amplitude expansion from the on-shell perspective. And we examine the EYM expansion using KLT relations and show how to evaluate the expansion coefficients efficiently.

    11. Flash Expansion Threshold in Whirligig Swarms.

      PubMed

      Romey, William L; Lamb, Alicia R

      2015-01-01

      In the selfish herd hypothesis, prey animals move toward each other to avoid the likelihood of being selected by a predator. However, many grouped animals move away from each other the moment before a predator attacks. Very little is known about this phenomenon, called flash expansion, such as whether it is triggered by one individual or a threshold and how information is transferred between group members. We performed a controlled experiment with whirligig beetles in which the ratio of sighted to unsighted individuals was systematically varied and emergent flash expansion was measured. Specifically, we examined: the percentage of individuals in a group that startled, the resulting group area, and the longevity of the flash expansion. We found that one or two sighted beetles in a group of 24 was not enough to cause a flash expansion after a predator stimulus, but four sighted beetles usually initiated a flash expansion. Also, the more beetles that were sighted the larger the resulting group area and the longer duration of the flash expansion. We conclude that flash expansion is best described as a threshold event whose adaptive value is to prevent energetically costly false alarms while quickly mobilizing an emergent predator avoidance response. This is one of the first controlled experiments of flash expansion, an important emergent property that has applications to understanding collective motion in swarms, schools, flocks, and human crowds. Also, our study is a convincing demonstration of social contagion, how the actions of one individual can pass through a group.

    12. National space transportation and support study/mission requirements and architecture studies

      NASA Technical Reports Server (NTRS)

      Durocher, C. L.; Darwin, C. R.

      1986-01-01

      The government approach to fulfilling the requirements of the National Space Transportation and Support Study is described. DOD and NASA were required to determine the architecture and technology that would be needed for civil and defense space transportation during the 1995-2010 time range. NASA collected data from the National Commission on Space and the DOD research focused on SDI requirements. The objectives and recommendations of the space transportation architecture, transportation and support systems, and technology assessment and planning tasks are discussed.

    13. Negative thermal expansion in the Russian blue analog Zn3[Fe(CN)6]2: x-ray diffraction and neutron vibrational studies

      SciTech Connect

      Nakotte, Heinz; Daemen, Luke; Adak, Sourav

      2009-01-01

      The cubic Prussian Blue (PB) analog, Zn{sub 3} [Fe(CN){sub 6}]{sub 2}, has been studied by X-ray powder diffraction and inelastic neutron scattering (INS). X-ray data collected at 300 and 84 K revealed negative thermal expansion (NTE) behavior for this material. The NTE coefficient was found to be -31.1 x 10{sup -6} K{sup -1}. The neutron vibrational spectrum for Zn{sub 3}[Fe(CN){sub 6}]{sub 2}.xH{sub 2}O, was studied in detail. The INS spectrum showed well-defined, well-separated bands corresponding to the stretching of and deformation modes of the Fe and Zn octahedra, all below 800 cm{sup -1}.

    14. [Multi-scenario simulation and prediction of ecosystem services as affected by urban expansion: A case study in coastal area of Tianjin, North China].

      PubMed

      Huang, Huan-Chun; Yun, Ying-Xia; Miao, Zhan-Tang; Hao, Cui; Li, Hong-yuan

      2013-03-01

      Based on the modified Logistic-CA model, and taking the coastal area of Tianjin as a case, this paper simulated the spatial evolution patterns of ecosystem services as affected by the urban expansion in 2011-2020 under the scenarios of historical extrapolation, endogenous development, and exogenous development. Overall, the total ecosystem services of the study area under the three scenarios were generally the same, and the functional region with the lowest level ecosystem services had the identical spatial pattern. However, the spatial evolution patterns of the ecosystem services of the study area under the three scenarios had a great difference. The functional regions with lower-level ecosystem services grew in a cross-shaped pattern, with the Tanggu downtown as a center, and finally formed a full connectivity area along the Haihe River and coastal zone.

    15. Studies of Immobilized Homogeneous Metal Catalysts on Silica Supports

      SciTech Connect

      Stanger, Keith James

      2003-01-01

      The tethered, chiral, chelating diphosphine rhodium complex, which catalyzes the enantioselective hydrogenation of methyl-α-acetamidocinnamate (MAC), has the illustrated structure as established by 31P NMR and IR studies. Spectral and catalytic investigations also suggest that the mechanism of action of the tethered complex is the same as that of the untethered complex in solution. The rhodium complexes, [Rh(COD)H]4, [Rh(COD)2]+BF4-, [Rh(COD)Cl]2, and RhCl3• 3H2O, adsorbed on SiO2 are optimally activated for toluene hydrogenation by pretreatment with H2 at 200 C. The same complexes on Pd-SiO2 are equally active without pretreatments. The active species in all cases is rhodium metal. The catalysts were characterized by XPS, TEM, DRIFTS, and mercury poisoning experiments. Rhodium on silica catalyzes the hydrogenation of fluorobenzene to produce predominantly fluorocyclohexane in heptane and 1,2-dichloroethane solvents. In heptane/methanol and heptane/water solvents, hydrodefluorination to benzene and subsequent hydrogenation to cyclohexane occurs exclusively. Benzene inhibits the hydrodefluorination of fluorobenzene. In DCE or heptane solvents, fluorocyclohexane reacts with hydrogen fluoride to form cyclohexene. Reaction conditions can be chosen to selectively yield fluorocyclohexane, cyclohexene, benzene, or cyclohexane. The oxorhenium(V) dithiolate catalyst [-S(CH2)3s-]Re(O)(Me)(PPh3) was modified by linking it to a tether that could be attached to a silica support. Spectroscopic investigation and catalytic oxidation reactivity showed the heterogenized catalyst's structure and reactivity to be similar to its homogeneous analog. However, the immobilized catalyst offered additional advantages of recyclability, extended stability, and increased resistance to deactivation.

    16. Does gypsum formation during sulfate attack on concrete lead to expansion?

      SciTech Connect

      Tian, B.; Cohen, M.D.

      2000-01-01

      Sulfate attack on Portland cement concrete is often said to arise from each of two major sulfate reactions: (1) The sulfate ions react with C{sub 3}A and its hydration products to form ettringite with an increase in volume that results in expansion and subsequent cracking of the concrete; (2) The sulfate ions react with calcium hydroxide (CH) to form gypsum. Even though gypsum formation is generally accepted to be harmful, the specific mechanism is not well established. Especially, the idea that gypsum formation leads to any expansion is controversial. This paper covers an investigation carried out to study the gypsum formation during sulfate attack and its consequences. Two parts are included: Part 1 consists of the results of a literature review describing different theories supporting and contradicting the idea that gypsum formation is expansive. Part 2 describes the laboratory investigation carried out by the authors. The results suggested that gypsum formation during sulfate attack may cause expansion.

    17. Effective Expansion: Balance between Shrinkage and Hygroscopic Expansion.

      PubMed

      Suiter, E A; Watson, L E; Tantbirojn, D; Lou, J S B; Versluis, A

      2016-05-01

      The purpose of this study was to investigate the relationship between hygroscopic expansion and polymerization shrinkage for compensation of polymerization shrinkage stresses in a restored tooth. One resin-modified glass-ionomer (RMGI) (Ketac Nano, 3M ESPE), 2 compomers (Dyract, Dentsply; Compoglass, Ivoclar), and a universal resin-based composite (Esthet•X HD, Dentsply) were tested. Volumetric change after polymerization ("total shrinkage") and during 4 wk of water storage at 37°C was measured using an optical method (n= 10). Post-gel shrinkage was measured during polymerization using a strain gauge method (n= 10). Extracted human molars with large mesio-occluso-distal slot preparations were restored with the tested restorative materials. Tooth surfaces at baseline (preparation), after restoration, and during 4 wk of 37°C water storage were scanned with an optical scanner to determine cuspal flexure (n= 8). Occlusal interface integrity was measured using dye penetration. Data were analyzed using analysis of variance and post hoc tests (significance level 0.05). All tested materials shrunk after polymerization. RMGI had the highest total shrinkage (4.65%) but lowest post-gel shrinkage (0.35%). Shrinkage values dropped significantly during storage in water but had not completely compensated polymerization shrinkage after 4 wk. All restored teeth initially exhibited inward (negative) cuspal flexure due to polymerization shrinkage. Cuspal flexure with the RMGI restoration was significantly less (-6.4 µm) than with the other materials (-12.1 to -14.1 µm). After 1 d, cuspal flexure reversed to +5.0 µm cuspal expansion with the RMGI and increased to +9.3 µm at 4 wk. After 4 wk, hygroscopic expansion compensated cuspal flexure in a compomer (Compoglass) and reduced flexure with Dyract and resin-based composite. Marginal integrity (93.7% intact restoration wall) was best for the Compoglass restorations and lowest (73.1%) for the RMGI restorations. Hygroscopic

    18. Steppe expansion in Patagonia?

      NASA Astrophysics Data System (ADS)

      Veblen, Thomas T.; Markgraf, Vera

      1988-11-01

      Westward expansion of the Patagonian steppe and retrocession of Andean forests due to increasing aridity over the past one or two millennia has been a persistent theme in the ecological and paleoecological literature for at least half a century. New evidence from pollen profiles, tree-ring analysis, vegetation structure, and photographic and documentary historical sources does not show the expansion of the steppe. Instead, over the past century trees have invaded the steppe as a consequence mainly of human-induced changes in the fire regime, and trees have regenerated in forest areas that were heavily burnt at the onset of European colonization.

    19. Supporting NGSS-aligned Study of Authentic Data about Climate

      NASA Astrophysics Data System (ADS)

      Zalles, D. R.

      2013-12-01

      The subject of climate change holds tremendous opportunity for students to learn how scientists use data to develop and test theories of how the natural world works and appreciate how climate change instantiates cross-cutting NGSS science themes like stability and change, energy and matter, and cause and effect. To do so, students and teachers need help seeing in authentic Earth system data complex climate interactions and generate plans for building greater understanding of the complexities through further data investigation. With ever-growing repositories of global and regional public data and user friendly tools for their display, K-12 educators are challenged to help students study data independently rather than through the usual pre-filtered didactic presentations of data found in textbooks. The paper will describe strategies for facilitating critical thinking about authentic climate-related data in two climate change education projects funded by NASA and NSF, as well as learning outcomes. Data Enhanced Investigations for Climate Change Education (dicce.sri.com) brings data from NASA satellite missions to classrooms. Studying Topography, Orographic Rainfall, and Ecosystems with Geospatial Information Technology (store.sri.com) provides recent climatological and vegetation data about certain study areas in California and New York plus geospatially distributed projected values of temperature, precipitation, and land cover in 2050 and 2099, derived from NCAR's A2 climate change model. Supportive resources help students move from naïve conceptions of simple linear relationships between variables into critical analysis of what other variables could be mediating those relationships. DICCE contains guides for how to interpret multiyear trends that are evident in the NASA mission data in relation to what we know about current climate change. If a learner plots a line of best fit across multiple months or years of regional data and notices that the line is either

    20. Educational Expansion and Field of Study: Trends in the Intergenerational Transmission of Educational Inequality in the Netherlands

      ERIC Educational Resources Information Center

      Kraaykamp, Gerbert; Tolsma, Jochem; Wolbers, Maarten H. J.

      2013-01-01

      In this paper we study to what extent parental field of study affects a person's educational level and field of study. We employ information on 8800 respondents from the Family Survey Dutch Population (1992-2009). Our results first of all show that, over the last five decades, economic fields of study have become more fashionable among men. In…

    1. Educational Expansion and Field of Study: Trends in the Intergenerational Transmission of Educational Inequality in the Netherlands

      ERIC Educational Resources Information Center

      Kraaykamp, Gerbert; Tolsma, Jochem; Wolbers, Maarten H. J.

      2013-01-01

      In this paper we study to what extent parental field of study affects a person's educational level and field of study. We employ information on 8800 respondents from the Family Survey Dutch Population (1992-2009). Our results first of all show that, over the last five decades, economic fields of study have become more fashionable among men. In…

    2. Study-MATE: Using Text Messaging to Support Student Transition to University Study

      ERIC Educational Resources Information Center

      Cahir, Jayde; Huber, Elaine; Handal, Boris; Dutch, Justin; Nixon, Mark

      2012-01-01

      Students are most likely to drop out of university when first attending. This article analyses the use of technology in supporting the transition process of "first time" university students enrolled in a second-year accounting course. Study-MATE, a study skills program utilising the university's learning management system (LMS)--Blackboard, Google…

    3. Study-MATE: Using Text Messaging to Support Student Transition to University Study

      ERIC Educational Resources Information Center

      Cahir, Jayde; Huber, Elaine; Handal, Boris; Dutch, Justin; Nixon, Mark

      2012-01-01

      Students are most likely to drop out of university when first attending. This article analyses the use of technology in supporting the transition process of "first time" university students enrolled in a second-year accounting course. Study-MATE, a study skills program utilising the university's learning management system (LMS)--Blackboard, Google…

    4. US country studies program: Support for climate change studies, national plans, and technology assessments

      SciTech Connect

      1996-12-31

      This paper describes the objectives of the next phase of the U.S. Country Studies Program which was launched in support of the Framework Convention on Climate Change (FCCC). The next phases of this program aim to: assist countries in preparing Climate Change Action plans; support technology assessments and development of technology initiatives; enhance exchange of information and expertise in support of FCCC. The program offers support for these processes in the form of handbooks which have been published to aid in preparing action plans, and to provide information on methane, forestry, and energy technologies. In addition an array of training workshops have been and are scheduled to offer hands on instruction to participants, expert advice is available from trained personnel, and modeling tools are available to aid in development of action plans.

    5. Health workforce planning and service expansion during an economic crisis: A case study of the national breast screening programme in Ireland.

      PubMed

      McHugh, S M; Tyrrell, E; Johnson, B; Healy, O; Perry, I J; Normand, C

      2015-12-01

      This article aims to estimate the workforce and resource implications of the proposed age extension of the national breast screening programme, under the economic constraints of reduced health budgets and staffing levels in the Irish health system. Using a mixed method design, a purposive sample of 20 participants were interviewed and data were analysed thematically (June-September 2012). Quantitative data (programme-level activity data, screening activity, staffing levels and screening plans) were used to model potential workload and resource requirements. The analysis indicates that over 90% operational efficiency was achieved throughout the first six months of 2012. Accounting for maternity leave (10%) and sick leave (3.5%), 16.1 additional radiographers (whole time equivalent) would be required for the workload created by the age extension of the screening programme, at 90% operational efficiency. The results suggest that service expansion is possible with relatively minimal additional radiography resources if the efficiency of the skill mix and the use of equipment are improved. Investing in the appropriate skill mix should not be limited to clinical groups but should also include administrative staff to manage and support the service. Workload modelling may contribute to improved health workforce planning and service efficiency.

    6. Computer Supported Collaborative Writing in Practice: An Activity Theoretical Study

      ERIC Educational Resources Information Center

      Blin, Francoise; Appel, Christine

      2011-01-01

      This paper addresses issues of language use and negotiation and utilizes cultural-historical activity theory (CHAT) as a framework to analyze and understand the complexity of the mediational and collaborative structures constituting computer supported collaborative writing in a second language (CSCWL2) activities. Following an introduction to CHAT…

    7. Using Jigsaw and Case Study for Supporting Online Collaborative Learning

      ERIC Educational Resources Information Center

      Pozzi, Francesca

      2010-01-01

      In CSCL contexts ("Computer Supported Collaborative Learning") collaborative activities with different levels of structuredeness are often used to foster discussion and exchange among students and enhance collaboration. In this field the debate around whether and to what extent it is useful to structure the activities proposed to students, is…

    8. Lessons from VET Providers Delivering Degrees: Case Studies. Support Document

      ERIC Educational Resources Information Center

      Callan, Victor J.; Bowman, Kaye

      2015-01-01

      The recent growth in the number of registered vocational education and training (VET) providers delivering associate degrees and bachelor degrees in their own right has been well publicized. However, little is known about why these VET providers have made this transition, what support is being provided to their staff and students, and how the…

    9. Expansion flow and cluster distributions originating from ultrafast-laser-induced fragmentation of thin metal films: A molecular-dynamics study

      SciTech Connect

      Upadhyay, Arun K.; Urbassek, Herbert M.

      2006-01-15

      Using molecular-dynamics simulation, we study the fragmentation patterns of ultrathin metal films as a function of the initial energization. The energization is assumed to occur instantaneously. Above the threshold for fragmentation, a homogeneous expansion of the exploding film is observed, in which a mixture of clusters of all sizes is found. The internal temperature of the clusters is constant, independent of space, time, and cluster size. The cluster size distribution can be characterized for small energizations as a biexponential distribution, but is better represented for larger energizations by a power law in cluster size m,{proportional_to}m{sup -{alpha}}, with an exponent {alpha} congruent with 2.8-3.1.

    10. NASA supporting studies for microgravity research on eye movements

      NASA Technical Reports Server (NTRS)

      Cohen, Bernard

      1990-01-01

      The purpose of the work on this project was to provide support for ground-based studies on the effects of gravity on eye movements. The effects of microgravity on the optokinetic eye movements of humans are investigated. OKN was induced by having subjects watch 3.3 deg stripes moving at 35 deg/s for 45 s in a binocular, head-fixed apparatus. The field (hor., 88 deg; vert., 72 deg), was rotated about axes that were upright or tilted 45 deg or 90 deg. The head was upright or tilted 45 deg on the body. Head-horizontal (yaw axis) and head-vertical (pitch axis) components of OKN were recorded with electro-oculography (EOG). Slow phase velocity vectors were determined relative to gravity. With the head upright, the axis of eye rotation during yaw axis OKN was coincident with the stimulus axis and the spatial vertical. With the head tilted 45 deg on the body, a persistent vertical component of eye velocity developed during yaw axis stimulation, and there was an average shift of the axis of eye rotation toward the spatial vertical of approximately 18 deg in six subjects. During oblique optokinetic stimulation with the head upright, the axis of eye rotation shifted 12 deg toward the spatial vertical. When the head was tilted, the axis of eye rotation rotated to the other side of the spatial vertical by 5.4 deg during the same oblique stimulation. This counter-rotation of the axis of eye rotation is similar to the 'Muller (E) effect', in which the perception of the upright counter-rotates to the opposite side of the spatial vertical when subjects are tilted in darkness. The data were simulated by a model of OKN. Despite the short OKAN time constants, strong horizontal to vertical cross-coupling was produced if the horizontal and vertical time constants were in proper ratio, and there was no suppression of nystagmus orthogonal to the stimulus direction. This shows that the spatial orientation of OKN can be due to a restructuring of the system matrix of velocity storage as a

    11. Continuing Studies in Support of Ultraviolet Observations of Planetary Atmospheres

      NASA Technical Reports Server (NTRS)

      Clark, John

      1997-01-01

      This program was a one-year extension of an earlier Planetary Atmospheres program grant, covering the period 1 August 1996 through 30 September 1997. The grant was for supporting work to complement an active program observing planetary atmospheres with Earth-orbital telescopes, principally the Hubble Space Telescope (HST). The recent concentration of this work has been on HST observations of Jupiter's upper atmosphere and aurora, but it has also included observations of Io, serendipitous observations of asteroids, and observations of the velocity structure in the interplanetary medium. The observations of Jupiter have been at vacuum ultraviolet wavelengths, including imaging and spectroscopy of the auroral and airglow emissions. The most recent HST observations have been at the same time as in situ measurements made by the Galileo orbiter instruments, as reflected in the meeting presentations listed below. Concentrated efforts have been applied in this year to the following projects: The analysis of HST WFPC 2 images of Jupiter's aurora, including the Io footprint emissions. We have performed a comparative analysis of the lo footprint locations with two magnetic field models, studied the statistical properties of the apparent dawn auroral storms on Jupiter, and found various other repeated patterns in Jupiter's aurora. Analysis and modeling of airglow and auroral Ly alpha emission line profiles from Jupiter. This has included modeling the aurora] line profiles, including the energy degradation of precipitating charged particles and radiative transfer of the emerging emissions. Jupiter's auroral emission line profile is self-absorbed, since it is produced by an internal source, and the resulting emission with a deep central absorption from the overlying atmosphere permits modeling of the depth of the emissions, plus the motion of the emitting layer with respect to the overlying atmospheric column from the observed Doppler shift of the central absorption. By contrast

    12. Relative contributions of naturalistic and constructed support: two studies of women with type 2 diabetes.

      PubMed

      Barrera, Manuel; Toobert, Deborah J; Strycker, Lisa A

      2014-02-01

      Do distinct sources of social support have differential effects on health? Although previous research has contrasted family and friend support (naturalistic support), research on the relative effects of naturalistic support and constructed support (e.g., support groups) is extremely rare. Two studies of women with type 2 diabetes were conducted that assessed the independent effects of naturalistic and constructed support on physical activity and glycosylated hemoglobin (HbA1c). Participants were women diagnosed with type 2 diabetes from the intervention arms of two randomized controlled trials: primarily European American women (Study 1; N = 163) and exclusively Hispanic women (Study 2; N = 142). Measures assessed physical activity, HbA1c, and friend and family support at baseline and at 6 months, as well as group support after 6 months of intervention. In Study 1, only group support was related to increases in physical activity (ΔR(2) = .036). In Study 2, group support and family support showed independent effects on increases in physical activity (ΔR(2) = .047 and .060, respectively). Also, group support was related to decreases in HbA1c in Study 1 (ΔR(2) = .031) and Study 2 (ΔR(2) = .065). Overall, constructed (group) support was related to outcomes most consistently, but naturalistic (family) support showed some independent relation to physical activity improvement.

    13. High temperature crystal chemistry and thermal expansion of synthetic powellite (CaMoO4): A high temperature X-ray diffraction (HT-XRD) study

      NASA Astrophysics Data System (ADS)

      Achary, S. N.; Patwe, S. J.; Mathews, M. D.; Tyagi, A. K.

      2006-04-01

      In this communication, the high temperature crystal chemistry of scheelite type (space group: I41/a) CaMoO4 (powellite) is reported. The details of the high temperature crystal structures were obtained by high temperature X-ray diffractometer (HT-XRD) data in the temperature range of 25 1000 °C. The lattice thermal expansions of this compound show the an-isotropic behavior, with the coefficient of thermal expansion along c-axis (αc) is almost double of that along the a-axis (αa). The average values of thermal expansion coefficient for CaMoO4 are: αa=13.5×10-6 and αc=22.8×10-6 °C. The typical thermal expansion behavior is basically controlled by the temperature-induced expansion of the Ca O bonds, i.e. by the thermal expansion of the CaO8 polyhedra. The MoO4 polyhedra acts as typical rigid unit, with virtually no expansion. The preliminary data analysis for CaWO4 indicates almost similar values of thermal expansion coefficients, viz. αa=12.7×10-6 and αc=21.4×10-6/°C (for CaWO4) in the same temperature range. The further details are explained in this manuscript.

    14. A Special Trinomial Expansion

      ERIC Educational Resources Information Center

      Ayoub, Ayoub B.

      2006-01-01

      In this article, the author takes up the special trinomial (1 + x + x[squared])[superscript n] and shows that the coefficients of its expansion are entries of a Pascal-like triangle. He also shows how to calculate these entries recursively and explicitly. This article could be used in the classroom for enrichment. (Contains 1 table.)

    15. 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.

    16. A Special Trinomial Expansion

      ERIC Educational Resources Information Center

      Ayoub, Ayoub B.

      2006-01-01

      In this article, the author takes up the special trinomial (1 + x + x[squared])[superscript n] and shows that the coefficients of its expansion are entries of a Pascal-like triangle. He also shows how to calculate these entries recursively and explicitly. This article could be used in the classroom for enrichment. (Contains 1 table.)

    17. Expansion of Pannes

      EPA Science Inventory

      For the Long Island, New Jersey, and southern New England region, one facet of marsh drowning as a result of accelerated sea level rise is the expansion of salt marsh ponds and pannes. Over the past century, marsh ponds and pannes have formed and expanded in areas of poor drainag...

    18. AUTO-EXPANSIVE FLOW

      EPA Science Inventory

      Physics suggests that the interplay of momentum, continuity, and geometry in outward radial flow must produce density and concomitant pressure reductions. In other words, this flow is intrinsically auto-expansive. It has been proposed that this process is the key to understanding...

    19. AUTO-EXPANSIVE FLOW

      EPA Science Inventory

      Physics suggests that the interplay of momentum, continuity, and geometry in outward radial flow must produce density and concomitant pressure reductions. In other words, this flow is intrinsically auto-expansive. It has been proposed that this process is the key to understanding...

    20. Expansion of Pannes

      EPA Science Inventory

      For the Long Island, New Jersey, and southern New England region, one facet of marsh drowning as a result of accelerated sea level rise is the expansion of salt marsh ponds and pannes. Over the past century, marsh ponds and pannes have formed and expanded in areas of poor drainag...

    1. Eigenfunction expansions for time dependent hamiltonians

      NASA Astrophysics Data System (ADS)

      Jauslin, H. R.; Guerin, S.; Deroussiaux, A.

      We describe a generalization of Floquet theory for non periodic time dependent Hamiltonians. It allows to express the time evolution in terms of an expansion in eigenfunctions of a generalized quasienergy operator. We discuss a conjecture on the extension of the adiabatic theorem to this type of systems, which gives a procedure for the physical preparation of Floquet states. *** DIRECT SUPPORT *** A3418380 00004

    2. 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.

    3. Parametric Studies Of Lightweight Reflectors Supported On Linear Actuator Arrays

      NASA Astrophysics Data System (ADS)

      Seibert, George E.

      1987-10-01

      This paper presents the results of numerous design studies carried out at Perkin-Elmer in support of the design of large diameter controllable mirrors for use in laser beam control, surveillance, and astronomy programs. The results include relationships between actuator location and spacing and the associated degree of correctability attainable for a variety of faceplate configurations subjected to typical disturbance environments. Normalizations and design curves obtained from closed-form equations based on thin shallow shell theory and computer based finite-element analyses are presented for use in preliminary design estimates of actuator count, faceplate structural properties, system performance prediction and weight assessments. The results of the analyses were obtained from a very wide range of mirror configurations, including both continuous and segmented mirror geometries. Typically, the designs consisted of a thin facesheet controlled by point force actuators which in turn were mounted on a structurally efficient base panel, or "reaction structure". The faceplate materials considered were fused silica, ULE fused silica, Zerodur, aluminum and beryllium. Thin solid faceplates as well as rib-reinforced cross-sections were treated, with a wide variation in thickness and/or rib patterns. The magnitude and spatial frequency distribution of the residual or uncorrected errors were related to the input error functions for mirrors of many different diameters and focal ratios. The error functions include simple sphere-to-sphere corrections, "parabolization" of spheres, and higher spatial frequency input error maps ranging from 0.5 to 7.5 cycles per diameter. The parameter which dominates all of the results obtained to date, is a structural descriptor of thin shell behavior called the characteristic length. This parameter is a function of the shell's radius of curvature, thickness, and Poisson's ratio of the material used. The value of this constant, in itself

    4. Morphokinetics of human blastocyst expansion in vitro.

      PubMed

      Huang, T T F; Chinn, K; Kosasa, T; Ahn, H J; Kessel, B

      2016-12-01

      Time-lapse imaging offers new tools to study dynamic processes of development such as blastocyst formation and expansion. This study quantitatively describes expansion in human blastocysts from donated oocytes. Measurements of hourly interval rate of changes in the blastocoel cross-sectional area revealed oscillatory pulses having 2-4 h periodicities. Two types of oscillations were distinguished. An E-Type ('expansion') had positive peak and positive or slightly negative trough interval rate of change values, and these characterized most of the expansion period. A C-type ('contraction') represented an infrequent but notable contraction of the blastocoel with loss of blastocoel fluid. These were reversible within 2-4 h in both groups and followed by further expansion. Therefore, oscillatory pulses are an intrinsic property of the trophectoderm. The zona seems to variably dampen the amplitude of these pulses. Expansion kinetics were compared between blastocysts with known positive (KID+) or negative (KID-) implantation outcomes. Regression analysis suggests that expansion may be relatively restricted in KID- embryos blastulating at relatively later times. These data extend observations in other mammalian systems and may provide information useful for clinical selection algorithms. Copyright © 2016. Published by Elsevier Ltd.

    5. Phylogeography of the armadillo Chaetophractus villosus (Dasypodidae Xenarthra): post-glacial range expansion from Pampas to Patagonia (Argentina).

      PubMed

      Poljak, Sebastián; Confalonieri, Viviana; Fasanella, Mariana; Gabrielli, Magalí; Lizarralde, Marta Susana

      2010-04-01

      We report a phylogeographic study of Chaetophractus villosus populations in Argentina. Control Region (CR) sequences (484 bp) were obtained for 76 C. villosus from 20 locations across the species whole distribution range. Seventeen new haplotypes were identified. The highest genetic variation and the earliest fossils were found in the Pampean Region, thus appearing as the most probable area of origin of the species. A general pattern of Contiguous Range Expansion (CRE) was revealed by Nested Clade Analysis (NCA) supported by mismatch analysis and Fu's test. The Pampean Region would have been the pre-expansion area, while Patagonia would have been the main dispersal route of contiguous expansion, possibly after the Pleistocenic glaciations.

    6. Evaluating Academic Workplaces: The Hyper-Expansive Environment Experienced by University Lecturers in Professional Fields

      ERIC Educational Resources Information Center

      Boyd, Pete; Smith, Caroline; Ilhan Beyaztas, Dilek

      2015-01-01

      Academic developers need to understand the situated workplaces of the academic tribes they are supporting. This study proposes the use of the expansive--restrictive workplace learning environment continuum as a tool for evaluation of academic workplaces. The tool is critically appraised through its application to the analysis of workplace…

    7. Evaluating Academic Workplaces: The Hyper-Expansive Environment Experienced by University Lecturers in Professional Fields

      ERIC Educational Resources Information Center

      Boyd, Pete; Smith, Caroline; Ilhan Beyaztas, Dilek

      2015-01-01

      Academic developers need to understand the situated workplaces of the academic tribes they are supporting. This study proposes the use of the expansive--restrictive workplace learning environment continuum as a tool for evaluation of academic workplaces. The tool is critically appraised through its application to the analysis of workplace…

    8. Roadway-powered-electric-vehicle impact study: preliminary supporting analyses

      SciTech Connect

      Latorre, V.R.; Spogen, L.R. Jr.

      1981-12-15

      The Roadway-Powered Electric Vehicle (RPEV) impact analysis program is described, and the results to date are presented. Expressions for the number of RPEVs and miles of powered roadways required to accomplish the desired replacement VMT in a USA have been derived, as well as a procedure to determine hourly energy demand resulting from using RPEVs and powered roadways. Conversions factors from VMT to electric energy have also been determined. The input and output data requirements for RECAPS have been determined, as well as the formats for the data for both the EPRI-supported effort, and the simpler, non-EPRI-supported program. The differences between the two programs are also discussed, and data are presented on the average VMT in each major utility service area within the US.

    9. Social Support among Immigrant Latino Men: A Validation Study

      PubMed Central

      Rhodes, Scott D.; Daniel, Jason; Song, Eun-Young; Alonzo, Jorge; Downs, Mario; Reboussin, Beth A.

      2015-01-01

      Objective To explore the factor structure of the Index of Sojourner’s Social Support (ISSS) within a sample of Spanish-speaking immigrant Latino men. Methods We explored the factor structure and calculated correlations to examine associations between the ISSS subscales and self-esteem, mastery, and depression. Results Mean age of the 244 participants was 26.9 years old and most were from Mexico, had less than high school educational attainment, and worked in construction. The ISSS did not perform as well as expected. Conclusions Although the ISSS may prove useful as we begin to conceptualize the role and meaning of social support within the context of immigration, more research is needed to develop meaningful measures of constructs among immigrant Latinos in the United States. PMID:23985284

    10. Expansion of flight simulator capability for study and solution of aircraft directional control problems on runways, appendixes

      NASA Technical Reports Server (NTRS)

      Mcgowan, J. A.

      1978-01-01

      The models used to implement the DC-9-10 aircraft simulation for the Runway Direction Control study are presented. The study was done on the Douglas Aircraft six-degree-of-freedom motion simulator. Documentation of the models was in algebraic form, to the extent possible. Effort was directed toward presenting what was actually done rather than general forms.

    11. U. S. Government Factors Influencing an Expansion of Study Abroad in the Middle East/North Africa

      ERIC Educational Resources Information Center

      Lane-Toomey, Cara

      2014-01-01

      As the United States continued to grow as a world power throughout the later part of the twentieth century, government funding for international education grew more closely connected to its national security needs. Federal funds have contributed to the growth of Area Studies and studying Less Commonly Taught Languages (LCTLs). Within the last ten…

    12. Flawed Execution: A Case Study on Operational Contract Support

      DTIC Science & Technology

      2016-06-01

      services as a whole have done a poor job of teaching their leaders how to effectively plan for and manage operational contract support, starting...has become a vital necessity. Despite the last decade and a half of armed conflict, the military services as a whole have done a poor job of teaching...several different vendors, thus bolstering the financial health of more than one company and increasing local employment. Coordinated effort leverages

    13. A blinded international study on the reliability of genetic testing for GGGGCC-repeat expansions in C9orf72 reveals marked differences in results among 14 laboratories

      PubMed Central

      Akimoto, Chizuru; Volk, Alexander E; van Blitterswijk, Marka; Van den Broeck, Marleen; Leblond, Claire S; Lumbroso, Serge; Camu, William; Neitzel, Birgit; Onodera, Osamu; van Rheenen, Wouter; Pinto, Susana; Weber, Markus; Smith, Bradley; Proven, Melanie; Talbot, Kevin; Keagle, Pamela; Chesi, Alessandra; Ratti, Antonia; van der Zee, Julie; Alstermark, Helena; Birve, Anna; Calini, Daniela; Nordin, Angelica; Tradowsky, Daniela C; Just, Walter; Daoud, Hussein; Angerbauer, Sabrina; DeJesus-Hernandez, Mariely; Konno, Takuya; Lloyd-Jani, Anjali; de Carvalho, Mamede; Mouzat, Kevin; Landers, John E; Veldink, Jan H; Silani, Vincenzo; Gitler, Aaron D; Shaw, Christopher E; Rouleau, Guy A; van den Berg, Leonard H; Van Broeckhoven, Christine; Rademakers, Rosa; Andersen, Peter M; Kubisch, Christian

      2014-01-01

      Background The GGGGCC-repeat expansion in C9orf72 is the most frequent mutation found in patients with amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Most of the studies on C9orf72 have relied on repeat-primed PCR (RP-PCR) methods for detection of the expansions. To investigate the inherent limitations of this technique, we compared methods and results of 14 laboratories. Methods The 14 laboratories genotyped DNA from 78 individuals (diagnosed with ALS or FTD) in a blinded fashion. Eleven laboratories used a combination of amplicon-length analysis and RP-PCR, whereas three laboratories used RP-PCR alone; Southern blotting techniques were used as a reference. Results Using PCR-based techniques, 5 of the 14 laboratories got results in full accordance with the Southern blotting results. Only 50 of the 78 DNA samples got the same genotype result in all 14 laboratories. There was a high degree of false positive and false negative results, and at least one sample could not be genotyped at all in 9 of the 14 laboratories. The mean sensitivity of a combination of amplicon-length analysis and RP-PCR was 95.0% (73.9–100%), and the mean specificity was 98.0% (87.5–100%). Overall, a sensitivity and specificity of more than 95% was observed in only seven laboratories. Conclusions Because of the wide range seen in genotyping results, we recommend using a combination of amplicon-length analysis and RP-PCR as a minimum in a research setting. We propose that Southern blotting techniques should be the gold standard, and be made obligatory in a clinical diagnostic setting. PMID:24706941

    14. Special Plant Species Determines Diet Breadth of Phytophagous Insects: A Study on Host Plant Expansion of the Host-Specialized Aphis gossypii Glover

      PubMed Central

      Wu, Wei; Liang, Xin Li; Zhao, Hai Yang; Xu, Ting Ting; Liu, Xiang Dong

      2013-01-01

      Host specialization is a ubiquitous character of phytophagous insects. The polyphagous population is usually composed of some subpopulations that can use only a few closely related plants. Cotton-melon aphids, Aphis gossypii Glover exhibited strong host specialization, and the cotton- and cucurbits-specialized biotypes had been clearly identified. However, the experimental work that addressed the roles of plant species in determining diet breadth of phytophagous insects is rare. In the present study, we took the artificial host transfer method to assess the role of two special plants, zucchini Cucurbita zucchini L. and cowpea Vigna unguiculata (Linn.) Walp, in regulating diet breadth of cotton- and cucurbits-specialized A. gossypii collected from cotton and cucumber fields and reared separately on the native host plant for ten years. The results showed that the cotton-specialized aphids did not directly use cucumber whereas the cucurbits-specialized did not use cotton regardless of the coexistence or separation of cotton and cucumber plants. Neither of the cotton- and cucurbits-specialized aphids could use capsicum Capsicum annuum, eggplant Solanum melongenahttp://en.wikipedia.org/wiki/Carolus_Linnaeus, tomato Solanum lycopersicum, maize Zea mayshttp://en.wikipedia.org/wiki/Carl_Linnaeus, and radish Raphanus sativus, however, both of them could use zucchini and cowpea. Moreover, the feeding experience on zucchini led the cotton-specialized aphids to use cucumber well and finally to be transformed into the cucurbits-specialized biotype. The short-term feeding experience on cowpea resulted in the diet breadth expansion of the cucurbits-specialized aphids to use cotton. On the other hand, the diet breadth expansion of the cucurbits- and cotton-specialized aphids was only realized by different species of plant. It concluded that the special host plant did induce the conversion of feeding habits in the cotton- and cucurbits-specialized aphids, and consequently broke the

    15. Ampliacion Interdisciplinar de los Estudios Hispanicos: Temas y Perspectivas (The Expansion of Interdisciplinary Hispanic Studies: Themes and Perspectives)

      ERIC Educational Resources Information Center

      Poyatos, Fernando

      1978-01-01

      States that works concerning hispanic studies traditionally deal with analyses of the Spanish language or with literary works. Emphasis is made on the need for an interdisciplinary approach. (Text is in Spanish.) (NCR)

    16. Ampliacion Interdisciplinar de los Estudios Hispanicos: Temas y Perspectivas (The Expansion of Interdisciplinary Hispanic Studies: Themes and Perspectives)

      ERIC Educational Resources Information Center

      Poyatos, Fernando

      1978-01-01

      States that works concerning hispanic studies traditionally deal with analyses of the Spanish language or with literary works. Emphasis is made on the need for an interdisciplinary approach. (Text is in Spanish.) (NCR)

    17. Advanced life support study. Modification 10: ECLSS logistical support analysis for Space Station Freedom

      NASA Technical Reports Server (NTRS)

      1993-01-01

      This addendum to the final report provides a description of the work performed under the subject contract. This report describes the work that was performed by SRS Technologies from Jan. 1992 - Jan. 1993. The work that was performed included the following: (1) a study of the Space Station Freedom (SSF) Preliminary Design Review (PDR) data package and an identification of the maintenance concept, structure, implementation plans, training plan, and the LSAR approach; development of a working ability with the ALSTAR and DATA Express software; (3) a review of the SSF maintenance concept; and (4) an update of the ALSTAR data base.

    18. When Social Support Fits into Your Luggage: Online Support Seeking and Its Effects on the Traditional Study Abroad Experience

      ERIC Educational Resources Information Center

      Mikal, Jude P.

      2011-01-01

      Dubbed the Net Generation, modern university students have grown up not only with advanced communication technologies at their disposal, but using such technologies to both maintain and create social networks of support. In a study abroad context, the maintenance of dual on- and offline personas provides students with the opportunity to demolish…

    19. Femtosecond dynamics of cluster expansion

      NASA Astrophysics Data System (ADS)

      Gao, Xiaohui; Wang, Xiaoming; Shim, Bonggu; Arefiev, Alexey; Tushentsov, Mikhail; Breizman, Boris; Downer, Mike

      2010-03-01

      Noble gas clusters irradiated by intense ultrafast laser expand quickly and become typical plasma in picosecond time scale. During the expansion, the clustered plasma demonstrates unique optical properties such as strong absorption and positive contribution to the refractive index. Here we studied cluster expansion dynamics by fs-time-resolved refractive index and absorption measurements in cluster gas jets after ionization and heating by an intense pump pulse. The refractive index measured by frequency domain interferometry (FDI) shows the transient positive peak of refractive index due to clustered plasma. By separating it from the negative contribution of the monomer plasma, we are able to determine the cluster fraction. The absorption measured by a delayed probe shows the contribution from clusters of various sizes. The plasma resonances in the cluster explain the enhancement of the absorption in our isothermal expanding cluster model. The cluster size distribution can be determined. A complete understanding of the femtosecond dynamics of cluster expansion is essential in the accurate interpretation and control of laser-cluster experiments such as phase-matched harmonic generation in cluster medium.

    20. Cluster expansions for correlated finite nuclei: The normalization integral

      NASA Astrophysics Data System (ADS)

      Guardiola, R.; Polls, A.

      1980-06-01

      Cluster expansions of various kinds are studied with regard to the calculation of the normalization integral in 16O. The factor Aviles-Hartog-Tolhoek cluster expansion is shown to be very satisfactory at third order. A diagrammatic analysis of this cluster expansion is also included and numerically tested.