Sample records for support studies expansion

  1. 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.

  2. 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…

  3. Laboratory testing of a long expansion rock bolt support for energy-absorbing applications

    NASA Astrophysics Data System (ADS)

    Skrzypkowski, Krzysztof

    2018-01-01

    The main purpose of rock support and reinforcement in underground mining is to maintain excavations safe and open for their intended lifespan. The basic type of rock mass reinforcement method both in ore and hard coal mining is rock bolt support. Very often, existing bolt support systems are not always capable of providing a reliable controlled performance. Therefore, in recent years energy-absorbing bolts which are exposed to dynamic loading, for example from rock burst caused by high rock stresses, earthquakes, or blasting have appeared. In this article particular attention was paid to short and long expansion bolts. Quasi-static tests of expansion bolts were carried out at the laboratory test facility in simulated mining conditions, especially for the KGHM Polska Miedź S.A. mines. In the underground mines of the Legnica-Głogów Copper District (LGOM) the main way to protect the room excavation is rock bolt support with a length from 1.2 m to 2.6 m. Rock bolt support longer than 2.6 m is considered as additional support of excavations and is increasingly being used to reinforce the roofs. The comparisons of energy-absorbing short and long expansion bolts with a length of 1.8m, 3.6m and 5.2m were presented. In addition, for elastic and plastic range of each bolts were determined.

  4. The Accelerated Schools Movement: Expansion and Support through Accelerated Schools Centers.

    ERIC Educational Resources Information Center

    Brunner, Ilse; And Others

    From 1987 to 1995, the Accelerated Schools Project moved from a two-school pilot project to a national movement of over 700 schools in 35 states. This paper examines how the Accelerated Schools Centers have helped the expansion of the accelerated schools movement by recruiting and supporting schools in their regions, and how their institutional…

  5. 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

    ... the Support of the Senior Medicare Patrol (SMP) Program ACTION: Notice of intent to provide expansion... funds for the support of the Senior Medicare Patrol (SMP) Program. This additional funding opportunity... program capacity to recruit, train, and support the SMP volunteer network. In addition, this funding...

  6. 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.

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

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

    Ding, Ke, E-mail: dk1118@yeah.net; Yang, Zhong; Xu, Jian-zhong, E-mail: xjzspine@163.com

    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 formore » 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

  8. A randomized experiment of issue framing and voter support of tax increases for health insurance expansion.

    PubMed

    Rodriguez, Hector P; Laugesen, Miriam J; Watts, Carolyn A

    2010-12-01

    To assess the effect of issue framing on voter support of tax increases for health insurance expansion. During October 2008, a random sample of registered voters (n=1203) were randomized to a control and two different 'framing' groups prior to being asked about their support for tax increases. The 'framing' groups listened to one of two statements: one emphasized the externalities or negative effects of the uninsured on the insured, and the other raised racial and ethnic disparities in health insurance coverage as a problem. All groups were asked the same questions: would they support tax increases to provide adequate and reliable health insurance for three groups, (1) all American citizens, (2) all children, irrespective of citizenship, and (3) all military veterans. Support for tax increases varied substantially depending on which group benefited from the expansion. Consensus on coverage for military veterans was highest (83.3%), followed by all children, irrespective of citizenship (64.7%), and all American citizens (60.1%). There was no statistically significant difference between voter support in the 'framing' and control groups or between the two frames. In multivariable analyses, political party affiliation was the strongest predictor of support. Voters agree on the need for coverage of military veterans, but are less united on the coverage of all children and American citizens. Framing was less important than party affiliation, suggesting that voters consider coverage expansions and related tax increases in terms of the characteristics of the targeted group, and their own personal political views and values rather than the broader impact of maintaining the status quo. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  9. Self-expansion and flow in couples' momentary experiences: an experience sampling study.

    PubMed

    Graham, James M

    2008-09-01

    The self-expansion model of close relationships posits that when couples engage in exciting and activating conjoint activities, they feel connected with their partners and more satisfied with their relationships. In the present study, the experience sampling method was used to examine the predictions of the self-expansion model in couples' momentary experiences. In addition, the author generated several new hypotheses by integrating the self-expansion model with existing research on flow. Over the course of 1 week, 20 couples were signaled at quasi-random intervals to provide data on 1,265 unique experiences. The results suggest that the level of activation experienced during an activity was positively related to experience-level relationship quality. This relationship was consistent across free-time and nonfree-time contexts and was mediated by positive affect. Activation was not found to predict later affect unless the level of activation exceeded what was typical for the individual. Also examined was the influence of interpersonal context and activity type on self-expansion. The results support the self-expansion model and suggest that it could be considered under the broader umbrella of flow.

  10. The Racial Divide in State Medicaid Expansions.

    PubMed

    Grogan, Colleen M; Park, Sunggeun Ethan

    2017-06-01

    This study considers five important questions related to the role of race in state-level public support for the Medicaid expansion: (1) whether public support for the Medicaid expansion varies across the American states; (2) whether public support is positively related to state adoption; (3) whether this support is racialized; (4) whether, if racialized, there is evidence of more state responsiveness to white support than to nonwhite (black and/or Latino) support; and (5) does the size of the nonwhite population matter more when white support is relatively low? Our findings suggest that while public support for the Medicaid expansion is high at the state level, especially in comparison to public support for the ACA, there are important variations across the states. Although overall public support is positively related to state adoption, we find that public support for the Medicaid expansion is racialized in two ways. First, there are large differences in support levels by race; and second, state adoption decisions are positively related to white opinion and do not respond to nonwhite support levels. Most importantly, there is evidence that when the size of the black population increases and white support levels are relatively low, the state is significantly less likely to expand the Medicaid program. Our discussion highlights the democratic deficits and racial bias at the state level around this important coverage policy. Copyright © 2017 by Duke University Press.

  11. 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. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. 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

  13. 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

  14. Experiments on Interfaces To Support Query Expansion.

    ERIC Educational Resources Information Center

    Beaulieu, M.

    1997-01-01

    Focuses on the user and human-computer interaction aspects of the research based on the Okapi text retrieval system. Three experiments implementing different approaches to query expansion are described, including the use of graphical user interfaces with different windowing techniques. (Author/LRW)

  15. 46 CFR 154.432 - Expansion and contraction.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 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 ... 46 Shipping 5 2011-10-01 2011-10-01 false Expansion and contraction. 154.432 Section 154.432...

  16. 46 CFR 154.432 - Expansion and contraction.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 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 ... 46 Shipping 5 2010-10-01 2010-10-01 false Expansion and contraction. 154.432 Section 154.432...

  17. Differences in radial expansion force among inferior vena cava filter models support documented perforation rates.

    PubMed

    Robins, J Eli; Ragai, Ihab; Yamaguchi, Dean J

    2018-05-01

    Inferior vena cava (IVC) filters are used in patients at risk for pulmonary embolism who cannot be anticoagulated. Unfortunately, these filters are not without risk, and complications include perforation, migration, and filter fracture. The most prevalent complication is filter perforation of the IVC, with incidence varying among filter models. To our knowledge, the mechanical properties of IVC filters have not been evaluated and are not readily available through the manufacturer. This study sought to determine whether differences in mechanical properties are similar to differences in documented perforation rates. The radial expansion forces of Greenfield (Boston Scientific, Marlborough, Mass), Cook Celect (Cook Medical, Bloomington, Ind), and Cook Platinum filters were analyzed with three replicates per group. The intrinsic force exerted by the filter on the measuring device was collected in real time during controlled expansion. Replicates were averaged and significance was determined by calculating analysis of covariance using SAS software (SAS Institute, Cary, NC). Each filter model generated a significantly different radial expansion force (P < .001), and force was distributed at significantly different rates (P < .001) during expansion. The largest radial expansion force at minimal caval diameter was seen in the Cook Platinum filter, followed by the Cook Celect and Greenfield filters. Radial force dispersion during expansion was greatest in the Cook Celect, followed by the Cook Platinum and Greenfield filters. Differences in radial expansion forces among IVC filter models are consistent with documented perforation rates. Cook Celect IVC filters have a higher incidence of perforation compared with Greenfield filters when they are left in place for >90 days. Evaluation of Cook Celect filters yielded a significantly higher radial expansion force at minimum caval diameter, with greater force dispersion during expansion. Copyright © 2018 Society for Vascular

  18. 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.

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

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

    Mann, Sarita; Kumar, Ranjan; Jindal, V. K., E-mail: jindal@pu.ac.in

    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 bemore » 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.« less

  20. Application of Long Expansion Rock Bolt Support in the Underground Mines of Legnica-Głogów Copper District

    NASA Astrophysics Data System (ADS)

    Skrzypkowski, Krzysztof; Korzeniowski, Waldemar; Zagórski, Krzysztof; Dudek, Piotr

    2017-09-01

    excavations, and it is increasingly frequently used to reinforce roofs and in rebuilding the underground mines of KGHM Polish Copper S.A. In order to conduct the laboratory tests that are most suitable for the mine conditions, and yet are carried out on a laboratory test facility, the Authors used a steel cylinder with an external diameter of 102 mm and a length of 600 mm, which was filled with a core of rock (dolomite) from the roofs of the mine workings. In addition the maximum load that took over the bolt support made of rods and connected with sleeves was determined. For the initial tension, the elastic and plastic range of the maximal displacements, which were measured by the rope encoder, were determined. The statical tests of the expansion rock bolt support were carried out at the laboratory of the Department of Underground Mining in simulated mine conditions. The test facility enables the study of the long bolt rods on a geometric scale of 1:1 for the different ways of fixing. The aim of the laboratory research was to obtain the stress-strain characteristics, of the long expansion rock bolt support with a steel bearing plate and a plate printed on a 3D printer.

  1. Support and rehabilitation of patients with pulmonary expansion deficit by using game therapy.

    PubMed

    Chacon, P F S; Schon, C F; Furtado, V H L A; Signoretti, G L A M; Oliveira, J P P; Ribeiro, A G; Wanderley, C D V; Diniz, A A R; Soares, H B

    2016-08-01

    Patients suffering from hypoventilation and pulmonary expansion deficit are at increased risk of developing pulmonary complications such as atelectasis, pneumonia or pleural effusion. These complications can increase the length of stay and spending on health, and generate long-term functional impairment. This study aims to produce a therapeutic alternative to the traditional method of lung re-expansion through incentive spirometry (IS) using the game therapy to build an innovative system. This system makes use of infrared and Bluetooth communication technology to associate the game therapy to EI. At the end of the system implementation, we expect to obtain good adhesion of the patient and the physiotherapists.

  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. Cost of Incremental Expansion of an Existing Family Medicine Residency Program.

    PubMed

    Ashkin, Evan A; Newton, Warren P; Toomey, Brian; Lingley, Ronald; Page, Cristen P

    2017-07-01

    Expanding residency training programs to address shortages in the primary care workforce is challenged by the present graduate medical education (GME) environment. The Medicare funding cap on new GME positions and reductions in the Health Resources and Services Administration (HRSA) Teaching Health Center (THC) GME program require innovative solutions to support primary care residency expansion. Sparse literature exists to assist in predicting the actual cost of incremental expansion of a family medicine residency program without federal or state GME support. In 2011 a collaboration to develop a community health center (CHC) academic medical partnership (CHAMP), was formed and created a THC as a training site for expansion of an existing family medicine residency program. The cost of expansion was a critical factor as no Federal GME funding or HRSA THC GME program support was available. Initial start-up costs were supported by a federal grant and local foundations. Careful financial analysis of the expansion has provided actual costs per resident of the incremental expansion of the residencyRESULTS: The CHAMP created a new THC and expanded the residency from eight to ten residents per year. The cost of expansion was approximately $72,000 per resident per year. The cost of incremental expansion of our residency program in the CHAMP model was more than 50% less than that of the recently reported cost of training in the HRSA THC GME program.

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

    NASA Astrophysics Data System (ADS)

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

    2015-03-01

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

  5. On skin expansion.

    PubMed

    Pamplona, Djenane C; Velloso, Raquel Q; Radwanski, Henrique N

    2014-01-01

    This article discusses skin expansion without considering cellular growth of the skin. An in vivo analysis was carried out that involved expansion at three different sites on one patient, allowing for the observation of the relaxation process. Those measurements were used to characterize the human skin of the thorax during the surgical process of skin expansion. A comparison between the in vivo results and the numerical finite elements model of the expansion was used to identify the material elastic parameters of the skin of the thorax of that patient. Delfino's constitutive equation was chosen to model the in vivo results. The skin is considered to be an isotropic, homogeneous, hyperelastic, and incompressible membrane. When the skin is extended, such as with expanders, the collagen fibers are also extended and cause stiffening in the skin, which results in increasing resistance to expansion or further stretching. We observed this phenomenon as an increase in the parameters as subsequent expansions continued. The number and shape of the skin expanders used in expansions were also studied, both mathematically and experimentally. The choice of the site where the expansion should be performed is discussed to enlighten problems that can lead to frustrated skin expansions. These results are very encouraging and provide insight into our understanding of the behavior of stretched skin by expansion. To our knowledge, this study has provided results that considerably improve our understanding of the behavior of human skin under expansion. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Analytic hierarchy process helps select site for limestone quarry expansion in Barbados.

    PubMed

    Dey, Prasanta Kumar; Ramcharan, Eugene K

    2008-09-01

    Site selection is a key activity for quarry expansion to support cement production, and is governed by factors such as resource availability, logistics, costs, and socio-economic-environmental factors. Adequate consideration of all the factors facilitates both industrial productivity and sustainable economic growth. This study illustrates the site selection process that was undertaken for the expansion of limestone quarry operations to support cement production in Barbados. First, alternate sites with adequate resources to support a 25-year development horizon were identified. Second, technical and socio-economic-environmental factors were then identified. Third, a database was developed for each site with respect to each factor. Fourth, a hierarchical model in analytic hierarchy process (AHP) framework was then developed. Fifth, the relative ranking of the alternate sites was then derived through pair wise comparison in all the levels and through subsequent synthesizing of the results across the hierarchy through computer software (Expert Choice). The study reveals that an integrated framework using the AHP can help select a site for the quarry expansion project in Barbados.

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

    PubMed

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

    2013-12-01

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

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

    PubMed

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

    2017-10-01

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

  9. Lattice-structures and constructs with designed thermal expansion coefficients

    DOEpatents

    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.

  10. Medicaid Expansion in a Litmus State: The Missouri Struggle.

    PubMed

    Brasfield, James

    2016-12-01

    For a century Missouri was a bellwether state in presidential elections, always picking the winner. Since 2008 it has been experiencing a partisan divide along urban/rural lines with President Obama losing the state twice. The battle over Medicaid expansion found a Democratic governor unable to convince a Republican legislative majority to support ACA-based expansion. The more highly partisan legislative environment has rendered traditional bargaining and negotiations impossible on the controversial question of Medicaid expansion.Despite supportive advocacy by hospitals and the business community, the Republican legislative leaders have opposed any movement on Medicaid expansion over the past four years. There will be a new occupant in the governor's mansion in 2017, which may create a fork in the road. Democrats are unlikely to regain a legislative majority, and one path is continued Republican refusal to consider expansion. The other path features the new governor responding to the national 2016 election outcome, and creating the prospects for a deal, perhaps around a waiver plan. Copyright © 2016 by Duke University Press.

  11. Meeting Canadian Forces Expansion Goals through Retention

    DTIC Science & Technology

    2010-05-01

    performed well) for the recognition they would receive, while at the same time supporting satisfaction of intrinsic needs, by reinforcing the good feeling...Expansion Goals Through Expansion 4. TITLE AND SUBTITLE 5. FUNDING NUMBERS LCol M.A. Nixon 6. AUTHOR(S) 7. PERFORMING ORGANIZATION NAME(S...AND ADDRESS(ES) 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING / MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSORING

  12. Serial Tissue Expansion at the Same Site in Pediatric Patients: Is the Subsequent Expansion Faster?

    PubMed Central

    Lee, Moon Ki; Park, Seong Oh; Choi, Tae Hyun

    2017-01-01

    Background Serial tissue expansion is performed to remove giant congenital melanocytic nevi. However, there have been no studies comparing the expansion rate between the subsequent and preceding expansions. In this study, we analyzed the rate of expansion in accordance with the number of surgeries, expander location, expander size, and sex. Methods A retrospective analysis was performed in pediatric patients who underwent tissue expansion for giant congenital melanocytic nevi. We tested four factors that may influence the expansion rate: The number of surgeries, expander location, expander size, and sex. The rate of expansion was calculated by dividing the ‘inflation amount’ by the ‘expander size’. Results The expansion rate, compared with the first-time group, was 1.25 times higher in the second-or-more group (P=0.04) and 1.84 times higher in the third-or-more group (P<0.01). The expansion rate was higher at the trunk than at other sites (P<0.01). There was a tendency of lower expansion rate for larger expanders (P=0.03). Sex did not affect the expansion rate. Conclusions There was a positive correlation between the number of surgeries and the expansion rate, a positive correlation between the expander location and the expansion rate, and a negative correlation between the expander size and the expansion rate. PMID:29076319

  13. 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. Copyright © 2016 Office national des forêts. Published by Elsevier B.V. All rights reserved.

  14. Hematoma Expansion Following Acute Intracerebral Hemorrhage

    PubMed Central

    Brouwers, H. Bart; Greenberg, Steven M.

    2013-01-01

    Intracerebral hemorrhage, the most devastating form of stroke, has no specific therapy proven to improve outcome by randomized controlled trial. Location and baseline hematoma volume are strong predictors of mortality, but are non-modifiable by the time of diagnosis. Expansion of the initial hematoma is a further marker of poor prognosis that may be at least partly preventable. Several risk factors for hematoma expansion have been identified, including baseline ICH volume, early presentation after symptom onset, anticoagulation, and the CT angiography spot sign. Although the biological mechanisms of hematoma expansion remain unclear, accumulating evidence supports a model of ongoing secondary bleeding from ruptured adjacent vessels surrounding the initial bleeding site. Several large clinical trials testing therapies aimed at preventing hematoma expansion are in progress, including aggressive blood pressure reduction, treatment with recombinant factor VIIa guided by CT angiography findings, and surgical intervention for superficial hematomas without intraventricular extension. Hematoma expansion is so far the only marker of outcome that is amenable to treatment and thus a potentially important therapeutic target. PMID:23466430

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

    DOT National Transportation Integrated Search

    2014-12-01

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

  16. LIF supports primitive endoderm expansion during pre-implantation development.

    PubMed

    Morgani, Sophie M; Brickman, Joshua M

    2015-10-15

    Embryonic stem cells (ESCs) are pluripotent cell lines that can be maintained indefinitely in an early developmental state. ESC culture conditions almost always require the cytokine LIF to maintain self-renewal. As ESCs are not homogeneous but contain multiple populations reminiscent of the blastocyst, identifying the target cells of LIF is necessary to understand the propagation of pluripotency. We recently found that LIF acts under self-renewing conditions to stimulate the fraction of ESCs that express extraembryonic markers, but has little impact on pluripotent gene expression. Here, we report that LIF has two distinct roles: it blocks early epiblast (Epi) differentiation, and it supports the expansion of primitive endoderm (PrE)-primed ESCs and PrE in vivo. We find that activation of JAK/STAT signalling downstream of LIF occurs initially throughout the pre-implantation embryo, but later marks the PrE. Moreover, the addition of LIF to cultured embryos increases the GATA6(+) PrE population, whereas inhibition of JAK/STAT signalling reduces both NANOG(+) epiblast and GATA6(+) PrE. The reduction of the NANOG(+) Epi might be explained by its precocious differentiation to later Epi derivatives, whereas the increase in PrE is mediated both by an increase in proliferation and inhibition of PrE apoptosis that is normally triggered in embryos with an excess of GATA6(+) cells. Thus, it appears that the relative size of the PrE is determined by the number of LIF-producing cells in the embryo. This suggests a mechanism by which the embryo adjusts the relative ratio of the primary lineages in response to experimental manipulation. © 2015. Published by The Company of Biologists Ltd.

  17. Perceived Parental Attitudes of Gender Expansiveness: Development and Preliminary Factor Structure of a Self-Report Youth Questionnaire

    PubMed Central

    Hidalgo, Marco A.; Chen, Diane; Garofalo, Robert; Forbes, Catherine

    2017-01-01

    Abstract Purpose: Parental acceptance of gender identity/expression in lesbian, gay, bisexual, transgender, and queer/questioning (LGBTQ+) youth moderates the effects of minority stress on mental health outcomes. Given this association, mental health clinicians of gender-expansive adolescents often assess the degree to which these youth perceive their parents/primary caregivers as accepting or nonaffirming of their gender identity and expression. While existing measures may reliably assess youth's perceptions of general family support, no known tool aids in the assessment an adolescent's perceived parental support related to adolescent gender-expansive experiences. Methods: To provide both clinicians and researchers with an empirically derived tool, the current study used factor analysis to explore an underlying factor structure of a brief questionnaire developed by subject-matter experts and pertaining to multiple aspects of perceived parental support in gender-expansive adolescents and young adults. Respondents were gender-expansive adolescents and young adults seeking care in an interdisciplinary gender-health clinic within a pediatric academic medical center in the Midwestern United States. Results: Exploratory factor analysis resulted in a 14-item questionnaire comprised of two subscales assessing perceived parental nonaffirmation and perceived parental acceptance. Internal consistency and construct validity results provided support for this new questionnaire. Conclusion: This study provides preliminary evidence of the factor structure, reliability and validity of the Parental Attitudes of Gender Expansiveness Scale for Youth (PAGES-Y). These findings demonstrate both the clinical and research utility of the PAGES-Y, a tool that can yield a more nuanced understanding of family-related risk and protective factors in gender-expansive adolescents. PMID:29159312

  18. Perceived Parental Attitudes of Gender Expansiveness: Development and Preliminary Factor Structure of a Self-Report Youth Questionnaire.

    PubMed

    Hidalgo, Marco A; Chen, Diane; Garofalo, Robert; Forbes, Catherine

    2017-01-01

    Purpose: Parental acceptance of gender identity/expression in lesbian, gay, bisexual, transgender, and queer/questioning (LGBTQ+) youth moderates the effects of minority stress on mental health outcomes. Given this association, mental health clinicians of gender-expansive adolescents often assess the degree to which these youth perceive their parents/primary caregivers as accepting or nonaffirming of their gender identity and expression. While existing measures may reliably assess youth's perceptions of general family support, no known tool aids in the assessment an adolescent's perceived parental support related to adolescent gender-expansive experiences. Methods: To provide both clinicians and researchers with an empirically derived tool, the current study used factor analysis to explore an underlying factor structure of a brief questionnaire developed by subject-matter experts and pertaining to multiple aspects of perceived parental support in gender-expansive adolescents and young adults. Respondents were gender-expansive adolescents and young adults seeking care in an interdisciplinary gender-health clinic within a pediatric academic medical center in the Midwestern United States. Results: Exploratory factor analysis resulted in a 14-item questionnaire comprised of two subscales assessing perceived parental nonaffirmation and perceived parental acceptance. Internal consistency and construct validity results provided support for this new questionnaire. Conclusion: This study provides preliminary evidence of the factor structure, reliability and validity of the Parental Attitudes of Gender Expansiveness Scale for Youth (PAGES-Y). These findings demonstrate both the clinical and research utility of the PAGES-Y, a tool that can yield a more nuanced understanding of family-related risk and protective factors in gender-expansive adolescents.

  19. 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…

  20. Hypersonic Research Vehicle (HRV) real-time flight test support feasibility and requirements study. Part 1: Real-time flight experiment support

    NASA Technical Reports Server (NTRS)

    Rediess, Herman A.; Ramnath, Rudrapatna V.; Vrable, Daniel L.; Hirvo, David H.; Mcmillen, Lowell D.; Osofsky, Irving B.

    1991-01-01

    The results are presented of a study to identify potential real time remote computational applications to support monitoring HRV flight test experiments along with definitions of preliminary requirements. A major expansion of the support capability available at Ames-Dryden was considered. The focus is on the use of extensive computation and data bases together with real time flight data to generate and present high level information to those monitoring the flight. Six examples were considered: (1) boundary layer transition location; (2) shock wave position estimation; (3) performance estimation; (4) surface temperature estimation; (5) critical structural stress estimation; and (6) stability estimation.

  1. 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

  2. Hyoid expansion with titanium plate and screw: a human cadaveric study using computer-assisted airway measurement.

    PubMed

    Toh, Song-Tar; Hsu, Pon-Poh; Tan, Kah Leong Alvin; Lu, Kuo-Sun Peter; Han, Hong-Juan

    2013-08-01

    Hyoid expansion with suspension can potentially increase the upper airway at the hypopharyngeal level, benefitting patients with sleep-related breathing disorder. To document the effect of hyoid expansion using titanium plate and screw on retrolingual hypopharyngeal airway dimension and to compare the airway dimension after isolated hyoid expansion with hyoid expansion + hyomandibular suspension. Anatomical cadaveric dissection study. This study was performed in a laboratory setting using human cadavers. This is an anatomical feasibility study of hyoid expansion using titanium plate and screw on 10 cadaveric human heads and necks. The hyoid bone is trifractured with bony cuts made just medial to the lesser cornu. The freed hyoid body and lateral segments are expanded and stabilized to a titanium adaptation plate. Computer-assisted airway measurement (CAM) was used to measure the airway dimension at the hypopharynx at the level of the tongue base before and after the hyoid expansion. The expanded hyoid bone was then suspended to the mandible, and the airway dimension was measured again with CAM. Airway dimension after isolated hyoid expansion with hyoid expansion with hyomandibular suspension. RESULTS Hyoid expansion with titanium plate and screw resulted in statistical significant increase in the retrolingual hypopharyngeal airway space in all of the 10 human cadavers. The mean (SD) increase in retroglossal area was 33.4 (13.2) mm² (P < .005) (range, 6.0-58.7 mm²). Hyoid expansion with hyomandibular suspension resulted in a greater degree of airway enlargement. The mean (SD) increase in retroglossal area was 99.4 (15.0) mm² (P < .005) (range, 81.9-127.5 mm²). The retrolingual hypopharyngeal airway space increased with hyoid expansion using titanium plate and screw in our human cadaveric study, measured using CAM. The degree of increase is further augmented with hyomandibular suspension.

  3. Geothermal expansion spool piston

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

    Reed, L. T.

    1985-08-06

    A packing supporting piston assembly removably securable to an end section of a production casing of a geothermal well, which end section is disposed above a well head. The piston assembly when so mounted has packing in abutting sealing contact with the end section of the production casing and also has packing that is in slidable sealing contact with the interior surface of the expansion spool. The piston assembly is of such structure that the pressures exerted by the packing on the end section of the casing and on the interior surface of the expansion spool are independently adjustable tomore » desired magnitudes. The degree of pressure exerted by the packing on the interior surface of the expansion spool is adjustable after the packing has been disposed within the confines of the spool. The piston assembly in a preferred form includes a circumferentially extending high temperature resisting grease seal situated within the confines of the piston assembly. In addition to the preferred form of the piston assembly, alternate forms of the piston assembly are provided, each of which permits the pressure exerted by the packing on the interior surface of the expansion spool to be adjusted to a desired magnitude and periodically varied as the same becomes necessary to maintain an effective seal.« less

  4. The Politics of Medicaid: Most Americans Are Connected to the Program, Support Its Expansion, and Do Not View It as Stigmatizing.

    PubMed

    Grogan, Colleen M; Park, Sunggeun Ethan

    2017-12-01

    Policy Points: More than half of Americans are connected to the Medicaid program-either through their own coverage or that of a family member or close friend-and are significantly more likely to view Medicaid as important and to support increases in spending, even among conservatives. This finding helps explain why Affordable Care Act repeal efforts faced (and will continue to face) strong public backlash. Policymakers should be aware that although renaming programs within Medicaid may have increased enrollment take-up, this destigmatization effort might have also increased program confusion and reduced support for Medicaid even among enrollees who say the program is important to them. Since the 1980s, Medicaid enrollment has expanded so dramatically that by 2015 two-thirds of Americans had some connection to the program in which either they themselves, a family member, or a close friend is currently or was previously enrolled. Utilizing a nationally representative survey-the Kaiser Family Foundation Poll: Medicare and Medicaid at 50 (n = 1,849)-and employing ordinal and logistic regression analyses, our study examines 3 questions: (1) are individuals with a connection to Medicaid more likely to view the program as important, (2) are they more likely to support an increase in Medicaid spending, and (3) are they more likely to support adoption of the Medicaid expansion offered under the Affordable Care Act? For each of these questions we examine whether partisanship and views of stigma also impact support for Medicaid and, if so, whether these factors overwhelm the impact of connection to the program. Controlling for the strong effect of partisanship, people with any connection to the Medicaid program are more likely to view the program as important than those with no connection. However, when it comes to increasing spending or expanding the program, the type of connection to the program matters. In particular, adults with current and previous Medicaid coverage and

  5. The Economic Impact of Medicaid Expansion on Pennsylvania.

    PubMed

    Price, Carter C; Donohue, Julie M; Saltzman, Evan; Woods, Dulani; Eibner, Christine

    2013-01-01

    The Affordable Care Act is a substantial reform of the U.S. health care insurance system. Using the RAND COMPARE model, researchers assessed the act's potential economic effects on Pennsylvania, factoring in an optional expansion of Medicaid, and found the state would enjoy significant net benefits. With or without the expansion of Medicaid, the act will increase insurance coverage to hundreds of thousands of Pennsylvanians, but the COMPARE model estimates that the expansion of Medicaid eligibility would cover an additional 350,000 people and bring more than $2 billion in federal spending into the state annually than if the state did not expand. Should the state expand Medicaid, the additional spending will add more than $3 billion a year to the state's GDP and support 35,000 jobs. But Medicaid expansion is not without cost for the state; the estimated cumulative effect on Pennsylvania's Medicaid spending will be $180 million higher with the expansion than without between 2014 and 2020. Substantial reductions in uncompensated care costs for hospitals are possible even without expansion, but savings to hospitals for uncompensated care funding are even larger with the Medicaid expansion, amounting to $550 million or more each year.

  6. [Optic nerve subarachnoid space expansion in MR imaging: a etiology study].

    PubMed

    Li, M; Xu, Q G; Wang, J Q; Wang, Y R; Zhao, J; Wei, S H

    2016-12-11

    Objective: To investigate spectrum of causes in optic nerve subarachnoid space (ONSS) expansion by using Magnetic Resonance Imaging (MRI). Methods: A retrospective study. Twenty-six patients (46 eyes) with ONSS expansion and 20 healthy adults (40 eyes) were recruited in Neuro-ophthalmology Department of Chinese PLA General Hospital from January, 2014 to December, 2015. The diameters were measured on the optic nerve (OND) and optic nerve sheath (ONSD) 2.4 mm behind the globe. ONSS was calculated by the formula of (ONSD-OND)/2. All participants were under went ophthalmologic examinations. The patients' clinical features, MRI and final diagnosis were analyzed. Qualitative data were compared between groups by using chi square test and quantitative data were compared by independent sample t test. Results: There was no statistically significant difference between ONSS group and control group with age, BMI and mean arterial blood pressure ( P> 0.05). Larger space was found in ONSS group with mean±standard deviation (SD) of (1.9±0.4) mm comparing to the control group with (1.2±0. 2) mm ( t= 2.879, P< 0.01). Bilateral ONSS expansion were found in 20 patients, 15 patients (75%) with cerebral venous sinus thrombosis (CVST), 2 patients (10%) with neurosyphilis, 2 patients (10%) with peri-neuritis and 1 patient (5%) with hydrocephalus. Unilateral ONSS expansion were seen in 6 patients, 4 patients (66.7%) with compressive lesson on anterior visual pathway, 1 patient (16.7%) with fungal infection and 1 patient (16.7%) with peri-neuritis. Conclusions: The CVST patients more frequently presented bilateral ONSS expansion. Unilateral ONSS expansion may indicate compressive lesions located on the anterior visual pathway. ( Chin J Ophthalmol , 2016 , 52 : 911-917).

  7. 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

  8. Large-scale assessment of polyglutamine repeat expansions in Parkinson disease

    PubMed Central

    Wang, Lisa; Aasly, Jan O.; Annesi, Grazia; Bardien, Soraya; Bozi, Maria; Brice, Alexis; Carr, Jonathan; Chung, Sun J.; Clarke, Carl; Crosiers, David; Deutschländer, Angela; Eckstein, Gertrud; Farrer, Matthew J.; Goldwurm, Stefano; Garraux, Gaetan; Hadjigeorgiou, Georgios M.; Hicks, Andrew A.; Hattori, Nobutaka; Klein, Christine; Jeon, Beom; Kim, Yun J.; Lesage, Suzanne; Lin, Juei-Jueng; Lynch, Timothy; Lichtner, Peter; Lang, Anthony E.; Mok, Vincent; Jasinska-Myga, Barbara; Mellick, George D.; Morrison, Karen E.; Opala, Grzegorz; Pihlstrøm, Lasse; Pramstaller, Peter P.; Park, Sung S.; Quattrone, Aldo; Rogaeva, Ekaterina; Ross, Owen A.; Stefanis, Leonidas; Stockton, Joanne D.; Silburn, Peter A.; Theuns, Jessie; Tan, Eng K.; Tomiyama, Hiroyuki; Toft, Mathias; Van Broeckhoven, Christine; Uitti, Ryan J.; Wirdefeldt, Karin; Wszolek, Zbigniew; Xiromerisiou, Georgia; Yueh, Kuo-Chu; Zhao, Yi; Gasser, Thomas; Maraganore, Demetrius M.; Krüger, Rejko

    2015-01-01

    Objectives: We aim to clarify the pathogenic role of intermediate size repeat expansions of SCA2, SCA3, SCA6, and SCA17 as risk factors for idiopathic Parkinson disease (PD). Methods: We invited researchers from the Genetic Epidemiology of Parkinson's Disease Consortium to participate in the study. There were 12,346 cases and 8,164 controls genotyped, for a total of 4 repeats within the SCA2, SCA3, SCA6, and SCA17 genes. Fixed- and random-effects models were used to estimate the summary risk estimates for the genes. We investigated between-study heterogeneity and heterogeneity between different ethnic populations. Results: We did not observe any definite pathogenic repeat expansions for SCA2, SCA3, SCA6, and SCA17 genes in patients with idiopathic PD from Caucasian and Asian populations. Furthermore, overall analysis did not reveal any significant association between intermediate repeats and PD. The effect estimates (odds ratio) ranged from 0.93 to 1.01 in the overall cohort for the SCA2, SCA3, SCA6, and SCA17 loci. Conclusions: Our study did not support a major role for definite pathogenic repeat expansions in SCA2, SCA3, SCA6, and SCA17 genes for idiopathic PD. Thus, results of this large study do not support diagnostic screening of SCA2, SCA3, SCA6, and SCA17 gene repeats in the common idiopathic form of PD. Likewise, this largest multicentered study performed to date excludes the role of intermediate repeats of these genes as a risk factor for PD. PMID:26354989

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

    PubMed

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

    2013-04-01

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

  10. Expansion of all multitrace tree level EYM amplitudes

    NASA Astrophysics Data System (ADS)

    Du, Yi-Jian; Feng, Bo; Teng, Fei

    2017-12-01

    In this paper, we investigate the expansion of tree level multitrace Einstein-Yang-Mills (EYM) amplitudes. First, we propose two types of recursive expansions of tree level EYM amplitudes with an arbitrary number of gluons, gravitons and traces by those amplitudes with fewer traces or/and gravitons. Then we give many support evidence, including proofs using the Cachazo-He-Yuan (CHY) formula and Britto-Cachazo-Feng-Witten (BCFW) recursive relation. As a byproduct, two types of generalized BCJ relations for multitrace EYM are further proposed, which will be useful in the BCFW proof. After one applies the recursive expansions repeatedly, any multitrace EYM amplitudes can be given in the Kleiss-Kuijf (KK) basis of tree level color ordered Yang-Mills (YM) amplitudes. Thus the Bern-Carrasco-Johansson (BCJ) numerators, as the expansion coefficients, for all multitrace EYM amplitudes are naturally constructed.

  11. Ultraprecise thermal expansion measurements of seven low expansion materials

    NASA Technical Reports Server (NTRS)

    Berthold, J. W., III; Jacobs, S. F.

    1976-01-01

    We summarize a large number of ultraprecise thermal expansion measurements made on seven different low expansivity materials. Expansion coefficients in the -150-300 C temperature range are shown for Owens-Illinois Cer-Vit C-101, Corning ULE 7971 (titanium silicate) and fused silica 7940, Heraeus-Schott Zerodur low-expansion material and Homosil fused silica, Universal Cyclops Invar LR-35, and Simonds Saw and Steel Super Invar.

  12. Ultraprecise thermal expansion measurements of seven low expansion materials.

    PubMed

    Berthold Iii, J W; Jacobs, S F

    1976-10-01

    We summarize a large number of ultraprecise thermal expansion measurements made on seven different low expansivity materials. Expansion coefficients in the -150-300 degrees C temperature range are shown for Owens-Illinois Cer-Vit C-101, Corning ULE 7971 (titanium silicate) and fused silica 7940, Heraeus-Schott Zerodur low-expansion material and Homosil fused silica, Universal Cyclops Invar LR-35, and Simonds Saw and Steel Super Invar.

  13. Culture materials affect ex vivo expansion of hematopoietic progenitor cells.

    PubMed

    LaIuppa, J A; McAdams, T A; Papoutsakis, E T; Miller, W M

    1997-09-05

    Ex vivo expansion of hematopoietic cells is important for applications such as cancer treatment, gene therapy, and transfusion medicine. While cell culture systems are widely used to evaluate the biocompatibility of materials for implantation, the ability of materials to support proliferation of primary human cells in cultures for reinfusion into patients has not been addressed. We screened a variety of commercially available polymer (15 types), metal (four types), and glass substrates for their ability to support expansion of hematopoietic cells when cultured under conditions that would be encountered in a clinical setting. Cultures of peripheral blood (PB) CD34+ cells and mononuclear cells (MNC) were evaluated for expansion of total cells and colony-forming unit-granulocyte monocyte (CFU-GM; progenitors committed to the granulocyte and/or monocyte lineage). Human hematopoietic cultures in serum-free medium were found to be extremely sensitive to the substrate material. The only materials tested that supported expansion at or near the levels of polystyrene were tissue culture polystyrene, Teflon perfluoroalkoxy, Teflon fluorinated ethylene propylene, cellulose acetate, titanium, new polycarbonate, and new polymethylpentene. MNC were less sensitive to the substrate materials than the primitive CD34+ progenitors, although similar trends were seen for expansion of the two cell populations on the substrates tested. CFU-GM expansion was more sensitive to substrate materials than was total cell expansion. The detrimental effects of a number of the materials on hematopoietic cultures appear to be caused by protein adsorption and/or leaching of toxins. Factors such as cleaning, sterilization, and reuse significantly affected the performance of some materials as culture substrates. We also used PB CD34+ cell cultures to examine the biocompatibility of gas-permeable cell culture and blood storage bags and several types of tubing commonly used with biomedical equipment

  14. 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.

  15. Does query expansion limit our learning? A comparison of social-based expansion to content-based expansion for medical queries on the internet.

    PubMed

    Pentoney, Christopher; Harwell, Jeff; Leroy, Gondy

    2014-01-01

    Searching for medical information online is a common activity. While it has been shown that forming good queries is difficult, Google's query suggestion tool, a type of query expansion, aims to facilitate query formation. However, it is unknown how this expansion, which is based on what others searched for, affects the information gathering of the online community. To measure the impact of social-based query expansion, this study compared it with content-based expansion, i.e., what is really in the text. We used 138,906 medical queries from the AOL User Session Collection and expanded them using Google's Autocomplete method (social-based) and the content of the Google Web Corpus (content-based). We evaluated the specificity and ambiguity of the expansion terms for trigram queries. We also looked at the impact on the actual results using domain diversity and expansion edit distance. Results showed that the social-based method provided more precise expansion terms as well as terms that were less ambiguous. Expanded queries do not differ significantly in diversity when expanded using the social-based method (6.72 different domains returned in the first ten results, on average) vs. content-based method (6.73 different domains, on average).

  16. Creative conceptual expansion: A combined fMRI replication and extension study to examine individual differences in creativity.

    PubMed

    Abraham, Anna; Rutter, Barbara; Bantin, Trisha; Hermann, Christiane

    2018-05-05

    The aims of this fMRI study were two-fold. The first objective of the study was to verify whether the findings associated with a previous fMRI study could be replicated in which a novel event-related experimental design was developed which rendered it possible to investigate the brain basis of creative conceptual expansion. The ability to widen the boundaries of conceptual structures is integral to creative idea generation, which makes conceptual expansion a core component of creative cognition. Creative conceptual expansion led to the engagement of brain regions that are known to be involved in the access, storage and relational integration of conceptual knowledge in the original study. These included the anterior inferior frontal gyrus, the temporal poles and the lateral frontal pole. These findings in relation to the brain basis of creative conceptual expansion were replicated in the current study. The second objective of this study was to evaluate the brain basis of individual differences in creative conceptual expansion. The high creative group relative to the low creative group was shown to exhibit greater activity in regions of the semantic cognition network as well as the salience network during creative conceptual expansion. The findings are discussed from the point of view of classical hypotheses about information processing biases that explain individual differences in creativity including flat associative hierarchies, defocused attention and cognitive disinhibition. Copyright © 2018 Elsevier Ltd. All rights reserved.

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

    PubMed Central

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

    2016-01-01

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

  18. 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

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

    PubMed

    Kusuma, Gina D; Brennecke, Shaun P; O'Connor, Andrea J; Kalionis, Bill; Heath, Daniel E

    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.

  20. Prescription Drug Utilization and Reimbursement Increased Following State Medicaid Expansion in 2014.

    PubMed

    Mahendraratnam, Nirosha; Dusetzina, Stacie B; Farley, Joel F

    2017-03-01

    health care resources, specifically prescription drugs. Although this hypothesis would benefit from further testing, it aligns with previous studies that have shown that Medicaid expansion has led to increased access to coverage and care. While enrollment contributes to the increase in prescription utilization and reimbursement, the drop in PMPQ utilization suggests that the patients entering the program are healthier than existing patients. This shows that risk pooling is working. However, the increase in PMPQ reimbursement suggests that new enrollment may not be the only factor driving reimbursement changes. Factors such as changes in product mix, risk pool composition, and drug pricing and their effects on total and per-member reimbursement should be evaluated in future studies. No outside funding supported this study. Mahendraratnam is currently a Worldwide Health Economics and Outcomes Research Pre-doctoral Fellow at Bristol-Myers Squibb and previously provided advisory services to public and private sector clients while employed at Avalere Health, an Inovalon Company, as well as completed an internship at Genentech, a member of the Roche Group. Farley and Dusetzina have no conflicts of interest to report. Preliminary results of this study were presented at the 2016 International Society for Pharmacoeconomics and Outcomes Research (ISPOR) 21st Annual Meeting in Washington, DC, on May 21-25, 2016, and the 2016 AcademyHealth Annual Research Meeting (ARM) in Boston, Massachusetts, on June 26-28, 2016. Study concept and design were contributed by Farley, Mahendraratnam, and Dusetzina. Mahendraratnam, Farley, and Dusetzina collected the data, and data interpretation was performed by all the authors. The manuscript was written by Mahendraratnam, Farley, and Dusetzina and revised by Farley, Dusetzina, and Mahendraratnam.

  1. Comparison and evaluation of stresses generated by rapid maxillary expansion and the implant-supported rapid maxillary expansion on the craniofacial structures using finite element method of stress analysis.

    PubMed

    Jain, Varun; Shyagali, Tarulatha R; Kambalyal, Prabhuraj; Rajpara, Yagnesh; Doshi, Jigar

    2017-12-01

    The study aimed to evaluate and compare the stress distribution and 3-dimensional displacements along the craniofacial sutures in between the Rapid maxillary Expansion (RME) and Implant supported RME (I-RME). METHODS: Finite element model of the skull and the implants were created using ANSYS software. The finite element model thus built composed of 537692 elements and 115694 nodes in RME model & 543078 elements and 117948 nodes with implants model. The forces were applied on the palatal surface of the posterior teeth to cause 5mm of transverse displacement on either side of the palatal halves, making it a total of 10mm. The stresses and the displacement values were obtained and interpreted. Varying pattern of stress and the displacements with both positive and negative values were seen. The maximum displacement was seen in the case of plain RME model and that too at Pterygomaxillary suture and Mid-palatal suture in descending order. In the case of I-RME maximum displacement was seen at Zygomaticomaxillary suture followed by Pterygomaxillary suture. The displacements produced in all the three planes of space for the plain RME model were greater in comparison to the Implant Supported RME model. And the stresses remained high for all the sutures in case of an I-RME. There is a definite difference in the stress and the displacement pattern produced by RME and I-RME model and each can be used according to the need of the patient. The stresses generated in case of conventional RME were considerably less than that of the I-RME for all the sutures.

  2. 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.…

  3. Clonal expansion under the microscope: studying lymphocyte activation and differentiation using live-cell imaging.

    PubMed

    Polonsky, Michal; Chain, Benjamin; Friedman, Nir

    2016-03-01

    Clonal expansion of lymphocytes is a hallmark of vertebrate adaptive immunity. A small number of precursor cells that recognize a specific antigen proliferate into expanded clones, differentiate and acquire various effector and memory phenotypes, which promote effective immune responses. Recent studies establish a large degree of heterogeneity in the level of expansion and in cell state between and within expanding clones. Studying these processes in vivo, while providing insightful information on the level of heterogeneity, is challenging due to the complex microenvironment and the inability to continuously track individual cells over extended periods of time. Live cell imaging of ex vivo cultures within micro fabricated arrays provides an attractive methodology for studying clonal expansion. These experiments facilitate continuous acquisition of a large number of parameters on cell number, proliferation, death and differentiation state, with single-cell resolution on thousands of expanding clones that grow within controlled environments. Such data can reveal stochastic and instructive mechanisms that contribute to observed heterogeneity and elucidate the sequential order of differentiation events. Intercellular interactions can also be studied within these arrays by following responses of a controlled number of interacting cells, all trapped within the same microwell. Here we describe implementations of live-cell imaging within microwell arrays for studies of lymphocyte clonal expansion, portray insights already gained from these experiments and outline directions for future research. These tools, together with in vivo experiments tracking single-cell responses, will expand our understanding of adaptive immunity and the ways by which it can be manipulated.

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

    PubMed Central

    Blæhr, Tue Lindberg

    2016-01-01

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

  5. 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

  6. Black carbon aerosol-induced Northern Hemisphere tropical expansion

    DOE PAGES

    Kovilakam, Mahesh; Mahajan, Salil

    2015-06-23

    Global climate models (GCMs) underestimate the observed trend in tropical expansion. Recent studies partly attribute it to black carbon (BC) aerosols, which are poorly represented in GCMs. In this paper, we conduct a suite of idealized experiments with the Community Atmosphere Model version 4 coupled to a slab ocean model forced with increasing BC concentrations covering a large swath of the estimated range of current BC radiative forcing while maintaining their spatial distribution. The Northern Hemisphere (NH) tropics expand poleward nearly linearly as BC radiative forcing increases (0.7° W -1 m 2), indicating that a realistic representation of BC couldmore » reduce GCM biases. We find support for the mechanism where BC-induced midlatitude tropospheric heating shifts the maximum meridional tropospheric temperature gradient poleward resulting in tropical expansion. Finally, we also find that the NH poleward tropical edge is nearly linearly correlated with the location of the Intertropical Convergence Zone, which shifts northward in response to increasing BC.« less

  7. [Tissular expansion in giant congenital nevi treatment].

    PubMed

    Nguyen Van Nuoi, V; Francois-Fiquet, C; Diner, P; Sergent, B; Zazurca, F; Franchi, G; Buis, J; Vazquez, M-P; Picard, A; Kadlub, N

    2014-08-01

    Surgical management of giant melanotic naevi remains a surgical challenge. Tissue expansion provides tissue of the same quality for the repair of defects. The aim of this study is to review tissular expansion for giant melanotic naevi. We conducted a retrospective study from 2000 to 2012. All children patients who underwent a tissular expansion for giant congenital naevi had been included. Epidemiological data, surgical procedure, complication rate and results had been analysed. Thirty-tree patients had been included; they underwent 61 procedures with 79 tissular-expansion prosthesis. Previous surgery, mostly simple excision had been performed before tissular expansion. Complete naevus excision had been performed in 63.3% of the cases. Complications occurred in 45% of the cases, however in 50% of them were minor. Iterative surgery increased the complication rate. Tissular expansion is a valuable option for giant congenital naevus. However, complication rate remained high, especially when iterative surgery is needed. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  8. Conformal expansions and renormalons

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

    Rathsman, J.

    2000-02-07

    The coefficients in perturbative expansions in gauge theories are factorially increasing, predominantly due to renormalons. This type of factorial increase is not expected in conformal theories. In QCD conformal relations between observables can be defined in the presence of a perturbative infrared fixed-point. Using the Banks-Zaks expansion the authors study the effect of the large-order behavior of the perturbative series on the conformal coefficients. The authors find that in general these coefficients become factorially increasing. However, when the factorial behavior genuinely originates in a renormalon integral, as implied by a postulated skeleton expansion, it does not affect the conformal coefficients.more » As a consequence, the conformal coefficients will indeed be free of renormalon divergence, in accordance with previous observations concerning the smallness of these coefficients for specific observables. The authors further show that the correspondence of the BLM method with the skeleton expansion implies a unique scale-setting procedure. The BLM coefficients can be interpreted as the conformal coefficients in the series relating the fixed-point value of the observable with that of the skeleton effective charge. Through the skeleton expansion the relevance of renormalon-free conformal coefficients extends to real-world QCD.« less

  9. 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).

  10. Supercritical flow characteristics at abrupt expansion structure

    NASA Astrophysics Data System (ADS)

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

    2017-10-01

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

  11. Mesenchymal stromal cell supported umbilical cord blood ex vivo expansion enhances regulatory T cells and reduces graft versus host disease.

    PubMed

    Fan, Xiubo; Gay, Florence Pik Hoon; Ong, Shin-Yeu; Ang, Justina May Lynn; Chu, Pat Pak Yan; Bari, Sudipto; Lim, Tony Kiat Hon; Hwang, William Ying Khee

    2013-05-01

    Double cord blood transplantation (DCBT) may shorten neutrophil and platelet recovery times compared with standard umbilical cord blood transplantation. However, DCBT may be associated with a higher incidence of graft versus host disease (GVHD). In this study, we explored the effect of ex vivo expansion of a single cord blood unit (CBU) in a DCBT setting on GVHD and engraftment. Post-thaw cryopreserved CBUs from cord blood banks, hereinafter termed "banked" CBUs, were co-cultured with confluent bone marrow mesenchymal stromal cells (MSCs) supplemented with a cytokine cocktail comprising 100 ng/mL stem cell factor, 50 ng/mL flt3-ligand, 100 ng/mL thrombopoietin and 20 ng/mL insulin-like growth factor binding protein 2 for 12 days. When DCBT of one unexpanded and one expanded CBU was performed in non-obese diabetic/severe combined immunodeficient-IL2Rgamma(null) (NOD/SCID-IL2γ(-/-), NSG) mice, the expanded CBU significantly boosted in vivo hematopoiesis of the unexpanded CBU. The median survival of NSG mice was significantly improved from 63.4% (range, 60.0-66.7%) for mice receiving only unexpanded units to 86.5% (range, 80.0-92.9%) for mice receiving an expanded unit (P < 0.001). The difference in survival appeared to be due to a lower incidence of GVHD in the mice receiving expanded cells. This effect on GVHD was mediated by a significant increase in regulatory T cells seen in the presence of MSC co-culture. MSC-supported ex vivo expansion of "banked" CBU boosted unexpanded CBU hematopoiesis in vivo, increased regulatory T cell content and decreased the incidence of GVHD. Copyright © 2013. Published by Elsevier Inc.

  12. Derivative expansion of wave function equivalent potentials

    NASA Astrophysics Data System (ADS)

    Sugiura, Takuya; Ishii, Noriyoshi; Oka, Makoto

    2017-04-01

    Properties of the wave function equivalent potentials introduced by the HAL QCD collaboration are studied in a nonrelativistic coupled-channel model. The derivative expansion is generalized, and then applied to the energy-independent and nonlocal potentials. The expansion coefficients are determined from analytic solutions to the Nambu-Bethe-Salpeter wave functions. The scattering phase shifts computed from these potentials are compared with the exact values to examine the convergence of the expansion. It is confirmed that the generalized derivative expansion converges in terms of the scattering phase shift rather than the functional structure of the non-local potentials. It is also found that the convergence can be improved by tuning either the choice of interpolating fields or expansion scale in the generalized derivative expansion.

  13. Optical fiber sensor based on a polymer optical fiber macro-bend to study thermal expansion of metals

    NASA Astrophysics Data System (ADS)

    Pakdeevanich, Paradorn

    2018-05-01

    Thermal expansion is an important parameter for characterization of metals. As metal is heated, the molecules vibrate more violently and expand in all direction. Investigators have focused to study the thermal strain. However, the amount of expansion is difficult to measure. An attempt has been made to develop an apparatus using optical technique. The principle of this system is the transformation of length changes into changes of light intensity. The purpose of this work is to design and develop an optical fiber sensor based on a macro-bend of a polymer optical fiber. In this system, thermal expansion of metal was converted into the rolling of a needle in which placed beneath a flat bar of metal. Optical fiber sensor was attached to the ended section of a needle. As the crimp tube of the fiber sensor was moved due to thermal expansion of metal, the bend radii of optical fiber sensor was changed. As a sequence, the loss induced by the bending effect was depended on the expansion of metal that changed with temperature. In this study, we utilized optical fiber sensor to monitor and compare the thermal expansion of copper, brass and aluminum. According to our experimental results, the linear response with temperature was reported. The measured values of coefficient of thermal expansion was analyzed to be 0.45, 0.35 and 0.32 a.u./°C for aluminum bar, brass bar and copper bar, respectively. In addition, the effect of the size of the diameter of a needle on the response of bending loss was investigated.

  14. 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)

  15. 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…

  16. SU-F-J-132: Evaluation of CTV-To-PTV Expansion for Whole Breast Radiotherapy

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

    Burgdorf, B; Freedman, G; Teo, B

    2016-06-15

    Purpose: The current standard CTV-to-PTV expansion for whole breast radiotherapy (WBRT) is 7mm, as recommended by RTOG-1005.This expansion is derived from the uncertainty due to patient positioning (±5mm) and respiratory motion (±5mm). We evaluated the expansion needed for respiratory motion uncertainty using 4DCT. After determining the appropriate expansion margins, RT plans were generated to evaluate the reduction in heart and lung dose. Methods: 4DCT images were acquired during treatment simulation and retrospectively analyzed for 34 WBRT patients. Breast CTVs were contoured on the maximum inhale and exhale phase. Breast CTV displacement was measured in the L-R, A-P, and SUP-INF directionsmore » using rigid registration between phase images. Averaging over the 34 patients, we determined the margin due to respiratory motion. Plans were generated for 10 left-sided cases comparing the new expansion with the 7mm PTV expansion. Results: The results for respiratory motion uncertainty are shown in Table 1. Drawing on previous work by White et al at Princess Margaret Hospital (1) (see supporting document for reference) which studied the uncertainty due to patient positioning, we concluded that, in total, a 5mm expansion was sufficient. The results for our suggested PTV margin are shown in Table 2, combining the patient positioning results from White et al with our respiratory motion results. The planning results demonstrating the heart and lung dose differences in the 5mm CTV-to-PTV expanded plan compared to the 7mm plan are shown in Table 3. Conclusion: Our work evaluating the expansion needed for respiratory motion along with previous work evaluating the expansion needed for setup uncertainty shows that a CTV-to-PTV expansion of 5mm is acceptable and conservative. By reducing the PTV expansion, significant dose reduction to the heart and lung are achievable.« less

  17. Analyzing the effects of urban expansion on land surface temperature patterns by landscape metrics: a case study of Isfahan city, Iran.

    PubMed

    Madanian, Maliheh; Soffianian, Ali Reza; Koupai, Saeid Soltani; Pourmanafi, Saeid; Momeni, Mehdi

    2018-03-03

    Urban expansion can cause extensive changes in land use and land cover (LULC), leading to changes in temperature conditions. Land surface temperature (LST) is one of the key parameters that should be considered in the study of urban temperature conditions. The purpose of this study was, therefore, to investigate the effects of changes in LULC due to the expansion of the city of Isfahan on LST using landscape metrics. To this aim, two Landsat 5 and Landsat 8 images, which had been acquired, respectively, on August 2, 1985, and July 4, 2015, were used. The support vector machine method was then used to classify the images. The results showed that Isfahan city had been encountered with an increase of impervious surfaces; in fact, this class covered 15% of the total area in 1985, while this value had been increased to 30% in 2015. Then LST zoning maps were created, indicating that the bare land and impervious surfaces categories were dominant in high temperature zones, while in the zones where water was present or NDVI was high, LST was low. Then, the landscape metrics in each of the LST zones were analyzed in relation to the LULC changes, showing that LULC changes due to urban expansion changed such landscape properties as the percentage of landscape, patch density, large patch index, and aggregation index. This information could be beneficial for urban planners to monitor and manage changes in the LULC patterns.

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

    PubMed

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

    2004-01-01

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

  19. 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.

  20. Expansion of mesenchymal stem cells under atmospheric carbon dioxide.

    PubMed

    Brodsky, Arthur Nathan; Zhang, Jing; Visconti, Richard P; Harcum, Sarah W

    2013-01-01

    Stem cells are needed for an increasing number of scientific applications, including both fundamental research and clinical disease treatment. To meet this rising demand, improved expansion methods to generate high quantities of high quality stem cells must be developed. Unfortunately, the bicarbonate buffering system - which relies upon an elevated CO2 environment - typically used to maintain pH in stem cell cultures introduces several unnecessary limitations in bioreactor systems. In addition to artificially high dissolved CO2 levels negatively affecting cell growth, but more importantly, the need to sparge CO2 into the system complicates the ability to control culture parameters. This control is especially important for stem cells, whose behavior and phenotype is highly sensitive to changes in culture conditions such as dissolved oxygen and pH. As a first step, this study developed a buffer to support expansion of mesenchymal stem cells (MSC) under an atmospheric CO2 environment in static cultures. MSC expanded under atmospheric CO2 with this buffer achieved equivalent growth rates without adaptation compared to those grown in standard conditions and also maintained a stem cell phenotype, self-renewal properties, and the ability to differentiate into multiple lineages after expansion. © 2013 American Institute of Chemical Engineers.

  1. Modelling potential landscape sediment delivery due to projected soybean expansion: a scenario study of the Balsas sub-basin, Cerrado, Maranhão state, Brazil.

    PubMed

    Barreto, Larissa; Schoorl, Jeroen M; Kok, Kasper; Veldkamp, Tom; Hass, Adriani

    2013-01-30

    In Brazil, agriculture expansion is taking place primarily in the Cerrado ecosystems. With the aim of supporting policy development and protecting the natural environment at relevant hotspots, a scenario study was conducted that concerned not only land-use change, but also the resulting effects on erosion and deposition. This coupled approach helped to evaluate potential landscape impacts of the land-use scenarios. In the study area, the Balsas sub-basin in Maranhão State, a model chain was used to model plausible future soybean expansion locations (CLUE-S model) and resulting sediment mobilization patterns (LAPSUS model) for a business-as-usual scenario. In the scenario, more erosion occurred in areas where the conversion of natural vegetation into soybean cultivation is likely to take place, but the generated sediments tended to accumulate mainly within the conversion areas, thus limiting the offsite effects of the increased erosion. These results indicated that when agricultural expansion is kept away from rivers, Cerrado conversion will have only a limited impact on the sediment loads of local rivers. Where land-use changes are most concentrated are coincident with areas where more new sediments are generated (higher erosion) and where more sediments are re-deposited. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

  2. National Science Board Approves VLA Expansion

    NASA Astrophysics Data System (ADS)

    2001-11-01

    The National Science Board, the governing body for the National Science Foundation (NSF), has approved an expansion project for the Very Large Array (VLA) radio telescope in New Mexico. The board recommended an NSF award of approximately 58.3 million for the project over the next decade. The action came at the Board's meeting in Washington on Nov. 15. The Very Large Array The Very Large Array "This approval means that the VLA, already the most scientifically productive ground-based telescope in all of astronomy, will remain at the cutting edge of astrophysical research through the coming decades," said Paul Vanden Bout, director of the National Radio Astronomy Observatory (NRAO). The expansion project will replace aging equipment left over from the VLA's construction during the 1970s with modern technology, improving the VLA's scientific capabilities more than tenfold. Using the existing 27 dish antennas, each weighing 230 tons, the Expanded VLA will have greatly improved ability to image distant celestial objects and to decipher the physical nature of those objects. In addition to the 58.3 million NSF allocation, the governments of Canada and Mexico plan to provide funding for the VLA expansion. The VLA Expansion Project was formally proposed to the NSF, which owns the VLA, last year. Also last year, the project received a strong endorsement from the Astronomy and Astrophysics Survey Committee of the National Research Council, the working arm of the National Academies of Sciences and Engineering. That committee had been given the task of setting nationwide priorities for astronomy spending over the next decade. The Survey Committee report listed the Expanded VLA as an important contributor to new understanding in three high-priority research areas for the next decade: studies of star and planet formation; research into black holes; and unraveling details about the "dawn of the modern universe." Dedicated in 1980, the VLA is the most powerful, flexible and widely

  3. An experimental study of arch perimeter and arch width increase with mandibular expansion: a finite element method.

    PubMed

    Baswaraj; Hemanth, M; Jayasudha; Patil, Chandrashekhargouda; Sunilkumar, P; Raghuveer, H P; Chandralekha, B

    2013-01-01

    The objective of this study was to estimate the increase in arch perimeter associated with mandibular lateral expansion, To estimate the increase in intermolar width with mandibular lateral expansion and to find out the changes of tooth inclination with mandibular expansion. The mandibular bone with dentition of indian skeletal specimen was obtained. The computer tomogram (CT) slices of the mandible were taken. Finite element model (FEM): Numerical representation of the geometry was created by dividing the geometry into finite number of elements and the elements were connected together with nodes at the junction. The result of the study showed when 10° of lateral expansion was applied to the lower buccal segment at the center of rotation found at 4.3 mm below the root apex of first molar, a space of 1.3 mm between the canine and first premolar, and thus an increase in arch perimeter of 2.6 mm. The tip of the mesiolingual cusp of the first molar moved 4.2 mm laterally, resulting in a change in intermolar width by 8.4 mm. Three-dimensional simulation showed that 1 mm of intermolar expansion increased the arch perimeter by 0.30 mm. As the finite element method evolves and scientists are able to more clearly define physical properties of biological tissues, more accurate information can be generated at the level that other analytical methods cannot fully provide data.This result would be of value clinically for prediction of the effects of mandibular expansion.

  4. 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.

  5. 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…

  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. 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

    2018-02-01

    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

  8. Soil physical quality response to sugarcane expansion in Brazil

    USDA-ARS?s Scientific Manuscript database

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

  9. 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

  10. Business Associations, Conservative Networks, and the Ongoing Republican War over Medicaid Expansion.

    PubMed

    Hertel-Fernandez, Alexander; Skocpol, Theda; Lynch, Daniel

    2016-04-01

    A major component of the Affordable Care Act involves the expansion of state Medicaid programs to cover the uninsured poor. In the wake of the 2012 Supreme Court decision upholding and modifying reform legislation, states can decide whether to expand Medicaid-and twenty states are still not proceeding as of August 2015. What explains state choices about participation in expansion, including governors' decisions to endorse expansion or not as well as final state decisions? We tackle this puzzle, focusing closely on outcomes and battles in predominantly Republican-led states. Like earlier scholars, we find that partisan differences between Democrats and Republicans are central, but we go beyond earlier analyses to measure added effects from two dueling factions within the Republican coalition: statewide business associations and cross-state networks of ideologically conservative organizations. Using both statistical modeling and case studies, we show that GOP-leaning or GOP-dominated states have been most likely to embrace the expansion when organized business support outweighs pressures from conservative networks. Our findings help make sense of ongoing state-level debates over a core part of health reform and shed new light on mounting policy tensions within the Republican Party. Copyright © 2016 by Duke University Press.

  11. 76 FR 55732 - Public Listening Sessions Regarding the Maritime Administration's Panama Canal Expansion Study...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-08

    ... infrastructure. The study is being conducted in four defined phases that are designed to present considerations... interpreter may submit their request at the time of registration at http://www.PanamaCanalStudy.com... Maritime Administration's Panama Canal Expansion Study and the America's Marine Highway Program AGENCY...

  12. Fine-Tuning of Neurogenesis is Essential for the Evolutionary Expansion of the Cerebral Cortex

    PubMed Central

    Poluch, Sylvie; Juliano, Sharon L.

    2015-01-01

    We used several animal models to study global and regional cortical surface expansion: The lissencephalic mouse, gyrencephalic normal ferrets, in which the parietal cortex expands more than the temporal cortex, and moderately lissencephalic ferrets, showing a similar degree of temporal and parietal expansion. We found that overall cortical surface expansion is achieved when specific events occur prior to surpragranular layer formation. (1) The subventricular zone (SVZ) shows substantial growth, (2) the inner SVZ contains an increased number of outer radial glia and intermediate progenitor cells expressing Pax6, and (3) the outer SVZ contains a progenitor cell composition similar to the combined VZ and inner SVZ. A greater parietal expansion is also achieved by eliminating the latero-dorsal neurogenic gradient, so that neurogenesis displays a similar developmental degree between parietal and temporal regions. In contrast, mice or lissencephalic ferrets show more advanced neurogenesis in the temporal region. In conclusion, we propose that global and regional cortical surface expansion rely on similar strategies consisting in altering the timing of neurogenic events prior to the surpragranular layer formation, so that more progenitor cells, and ultimately more neurons, are produced. This hypothesis is supported by findings from a ferret model of lissencephaly obtained by transiently blocking neurogenesis during the formation of layer IV. PMID:23968831

  13. 77 FR 58404 - Announcing the Award of Three Single-Source Program Expansion Supplement Grants to Unaccompanied...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-20

    ...] Announcing the Award of Three Single-Source Program Expansion Supplement Grants to Unaccompanied Alien... its Unaccompanied Alien Children's Program to two organizations, Florence Crittenton Services of... unaccompanied alien children through September 30, 2012. The supplement grant will support the expansion of bed...

  14. Skeletal response to maxillary protraction with and without maxillary expansion: a finite element study.

    PubMed

    Gautam, Pawan; Valiathan, Ashima; Adhikari, Raviraj

    2009-06-01

    The purpose of this finite element study was to evaluate biomechanically 2 treatment modalities-maxillary protraction alone and in combination with maxillary expansion-by comparing the displacement of various craniofacial structures. Two 3-dimensional analytical models were developed from sequential computed tomography scan images taken at 2.5-mm intervals of a dry young skull. AutoCAD software (2004 version, Autodesk, San Rafael, Calif) and ANSYS software (version 10, Belcan Engineering Group, Cincinnati, Ohio) were used. The model consisted of 108,799 solid 10 node 92 elements, 193,633 nodes, and 580,899 degrees of freedom. In the first model, maxillary protraction forces were simulated by applying 1 kg of anterior force 30 degrees downward to the palatal plane. In the second model, a 4-mm midpalatal suture opening and maxillary protraction were simulated. Forward displacement of the nasomaxillary complex with upward and forward rotation was observed with maxillary protraction alone. No rotational tendency was noted when protraction was carried out with 4 mm of transverse expansion. A tendency for anterior maxillary constriction after maxillary protraction was evident. The amounts of displacement in the frontal, vertical, and lateral directions with midpalatal suture opening were greater compared with no opening of the midpalatal suture. The forward and downward displacements of the nasomaxillary complex with maxillary protraction and maxillary expansion more closely approximated the natural growth direction of the maxilla. Displacements of craniofacial structures were more favorable for the treatment of skeletal Class III maxillary retrognathia when maxillary protraction was used with maxillary expansion. Hence, biomechanically, maxillary protraction combined with maxillary expansion appears to be a superior treatment modality for the treatment of maxillary retrognathia than maxillary protraction alone.

  15. Surgically assisted rapid maxillary expansion in adults.

    PubMed

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

    1992-01-01

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

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

    PubMed

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

    2017-01-01

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

  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. Simplifying Bridge Expansion Joint Design and Maintenance

    DOT National Transportation Integrated Search

    2011-10-19

    This report presents a study focused on identifying the most durable expansion joints for the South : Carolina Department of Transportation. This is performed by proposing a degradation model for the : expansion joints and updating it based on bridge...

  19. Thermal expansion of boron subnitrides

    NASA Astrophysics Data System (ADS)

    Cherednichenko, Kirill A.; Gigli, Lara; Solozhenko, Vladimir L.

    2018-07-01

    The lattice parameters of two boron subnitrides, B13N2 and B50N2, have been measured as a function of temperature between 298 and 1273 K, and the corresponding thermal expansion coefficients have been determined. Thermal expansion of both boron subnitrides was found to be quasi-linear, and the volume thermal expansion coefficients of B50N2 (15.7 (2) × 10-6 K-1) and B13N2 (21.3 (2) × 10-6 K-1) are of the same order of magnitude as those of boron-rich compounds with structure related to α-rhombohedral boron. For both boron subnitrides no temperature-induced phase transitions have been observed in the temperature range under study.

  20. Expansion tube test time predictions

    NASA Technical Reports Server (NTRS)

    Gourlay, Christopher M.

    1988-01-01

    The interaction of an interface between two gases and strong expansion is investigated and the effect on flow in an expansion tube is examined. Two mechanisms for the unsteady Pitot-pressure fluctuations found in the test section of an expansion tube are proposed. The first mechanism depends on the Rayleigh-Taylor instability of the driver-test gas interface in the presence of a strong expansion. The second mechanism depends on the reflection of the strong expansion from the interface. Predictions compare favorably with experimental results. The theory is expected to be independent of the absolute values of the initial expansion tube filling pressures.

  1. Platelet lysate supports the in vitro expansion of human periodontal ligament stem cells for cytotherapeutic use.

    PubMed

    Wu, Rui-Xin; Yu, Yang; Yin, Yuan; Zhang, Xi-Yu; Gao, Li-Na; Chen, Fa-Ming

    2017-08-01

    Human platelet lysate (PL) produced under optimal conditions of standardization and safety has been increasingly suggested as the future 'gold standard' supplement to replace fetal bovine serum (FBS) for the ex vivo propagation of mesenchymal stem cells for translational medicine and cell therapy applications. However, the multifaceted effects of PL on tissue-specific stem cells remain largely unexplored. In the present study, we investigated the stem cell behaviours of human periodontal ligament stem cells (PDLSCs) in media with or without PL. Our data indicate that human PL, either as an adjuvant for culture media or as a substitute for FBS, supports the proliferation and expansion of human PDLSCs derived from either 'young' or 'old' donors to the same extent as FBS, without interfering with their immunomodulatory capacities. Although PL appears to inhibit the in vitro differentiation of 'young' or 'old' PDLSCs, their decreased osteogenic potential may be restored to similar or higher levels compared with FBS-expanded cells. PL- and FBS-expanded PDLSCs exhibited a similar potential to form mineralized nodules and expressed similar levels of osteogenic genes. Our data indicate that large clinically relevant quantities of PDLSCs may be yielded by the use of human PL; however, further analysis of its precise composition and function will pave the way for determining optimized, defined culture conditions. In addition to the potential increase in patient safety, our findings highlight the need for further research to develop the potential of PL-expanded PDLSCs for clinical use. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  2. Range expansion of heterogeneous populations.

    PubMed

    Reiter, Matthias; Rulands, Steffen; Frey, Erwin

    2014-04-11

    Risk spreading in bacterial populations is generally regarded as a strategy to maximize survival. Here, we study its role during range expansion of a genetically diverse population where growth and motility are two alternative traits. We find that during the initial expansion phase fast-growing cells do have a selective advantage. By contrast, asymptotically, generalists balancing motility and reproduction are evolutionarily most successful. These findings are rationalized by a set of coupled Fisher equations complemented by stochastic simulations.

  3. MiR-17 Partly Promotes Hematopoietic Cell Expansion through Augmenting HIF-1α in Osteoblasts

    PubMed Central

    Yang, Yuxia; Ma, Wei; Wu, Dan; Huang, Yu; Li, Hongge; Zou, Junhua; Zhang, Yanju; Feng, Meifu; Luo, Jianyuan

    2013-01-01

    Background Hematopoietic stem cell (HSC) regulation is highly dependent on interactions with the marrow microenvironment, of which osteogenic cells play a crucial role. While evidence is accumulating for an important role of intrinsic miR-17 in regulating HSCs and HPCs, whether miR-17 signaling pathways are also necessary in the cell-extrinsic control of hematopoiesis hereto remains poorly understood. Methodology/Principal Findings Using the immortalized clone with the characteristics of osteoblasts, FBMOB-hTERT, in vitro expansion, long-term culture initiating cell (LTC-IC) and non-obese diabetic/severe combined immunodeficient disease (NOD/SCID) mice repopulating cell (SRC) assay revealed that the ectopic expression of miR-17 partly promoted the ability of FBMOB-hTERT to support human cord blood (CB) CD34+ cell expansion and maintain their multipotency. It also seemed that osteoblastic miR-17 was prone to cause a specific expansion of the erythroid lineage. Conversely, deficient expression of miR-17 partly inhibited the hematopoietic supporting ability of FBMOB-hTERT. We further identified that HIF-1α is responsible for, at least in part, the promoted hematopoietic supporting ability of FBMOB-hTERT caused by miR-17. HIF-1α expression is markedly enhanced in miR-17 overexpressed FBMOB-hTERT upon interaction with CB CD34+ cells compared to other niche associated factors. More interestingly, the specific erythroid lineage expansion of CB CD34+ cells caused by osteoblastic miR-17 was abrogated by HIF-1α knock down. Conclusion/Significance Our data demonstrated that CB CD34+ cell expansion can be partly promoted by osteoblastic miR-17, and in particular, ectopic miR-17 can cause a specific expansion of the erythroid lineage through augmenting HIF-1α in osteoblasts. PMID:23936170

  4. 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.

  5. Electric Grid Expansion Planning with High Levels of Variable Generation

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

    Hadley, Stanton W.; You, Shutang; Shankar, Mallikarjun

    2016-02-01

    Renewables are taking a large proportion of generation capacity in U.S. power grids. As their randomness has increasing influence on power system operation, it is necessary to consider their impact on system expansion planning. To this end, this project studies the generation and transmission expansion co-optimization problem of the US Eastern Interconnection (EI) power grid with a high wind power penetration rate. In this project, the generation and transmission expansion problem for the EI system is modeled as a mixed-integer programming (MIP) problem. This study analyzed a time series creation method to capture the diversity of load and wind powermore » across balancing regions in the EI system. The obtained time series can be easily introduced into the MIP co-optimization problem and then solved robustly through available MIP solvers. Simulation results show that the proposed time series generation method and the expansion co-optimization model and can improve the expansion result significantly after considering the diversity of wind and load across EI regions. The improved expansion plan that combines generation and transmission will aid system planners and policy makers to maximize the social welfare. This study shows that modelling load and wind variations and diversities across balancing regions will produce significantly different expansion result compared with former studies. For example, if wind is modeled in more details (by increasing the number of wind output levels) so that more wind blocks are considered in expansion planning, transmission expansion will be larger and the expansion timing will be earlier. Regarding generation expansion, more wind scenarios will slightly reduce wind generation expansion in the EI system and increase the expansion of other generation such as gas. Also, adopting detailed wind scenarios will reveal that it may be uneconomic to expand transmission networks for transmitting a large amount of wind power through a long

  6. The ideas behind self-consistent expansion

    NASA Astrophysics Data System (ADS)

    Schwartz, Moshe; Katzav, Eytan

    2008-04-01

    In recent years we have witnessed a growing interest in various non-equilibrium systems described in terms of stochastic nonlinear field theories. In some of those systems, like KPZ and related models, the interesting behavior is in the strong coupling regime, which is inaccessible by traditional perturbative treatments such as dynamical renormalization group (DRG). A useful tool in the study of such systems is the self-consistent expansion (SCE), which might be said to generate its own 'small parameter'. The self-consistent expansion (SCE) has the advantage that its structure is just that of a regular expansion, the only difference is that the simple system around which the expansion is performed is adjustable. The purpose of this paper is to present the method in a simple and understandable way that hopefully will make it accessible to a wider public working on non-equilibrium statistical physics.

  7. Iterative expansion microscopy.

    PubMed

    Chang, Jae-Byum; Chen, Fei; Yoon, Young-Gyu; Jung, Erica E; Babcock, Hazen; Kang, Jeong Seuk; Asano, Shoh; Suk, Ho-Jun; Pak, Nikita; Tillberg, Paul W; Wassie, Asmamaw T; Cai, Dawen; Boyden, Edward S

    2017-06-01

    We recently developed a method called expansion microscopy, in which preserved biological specimens are physically magnified by embedding them in a densely crosslinked polyelectrolyte gel, anchoring key labels or biomolecules to the gel, mechanically homogenizing the specimen, and then swelling the gel-specimen composite by ∼4.5× in linear dimension. Here we describe iterative expansion microscopy (iExM), in which a sample is expanded ∼20×. After preliminary expansion a second swellable polymer mesh is formed in the space newly opened up by the first expansion, and the sample is expanded again. iExM expands biological specimens ∼4.5 × 4.5, or ∼20×, and enables ∼25-nm-resolution imaging of cells and tissues on conventional microscopes. We used iExM to visualize synaptic proteins, as well as the detailed architecture of dendritic spines, in mouse brain circuitry.

  8. Removable Type Expansion Bolt Innovative Design

    NASA Astrophysics Data System (ADS)

    Wang, Feng-Lan; Zhang, Bo; Gao, Bo; Liu, Yan-Xin; Gao, Bo

    2016-05-01

    Expansion bolt is a kind of the most common things in our daily life. Currently, there are many kinds of expansion bolts in the market. However, they have some shortcomings that mainly contain underuse and unremovement but our innovation of design makes up for these shortcomings very well. Principle of working follows this: expansion tube is fixed outside of bolt, steel balls and expansion covers are fixed inside. Meanwhile, the steel balls have 120° with each other. When using it ,expansion cover is moved in the direction of its internal part. So the front part of expansion bolt cover is increasingly becoming big and steel halls is moved outside. Only in this way can it be fixed that steel balls make expansion tube expand. When removing them, expansion bolt is moved outside. So the front part of expansion bolt cover is gradually becoming small and steel balls moves inside, after expansion tube shrinks, we can detach them.

  9. 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.

  10. On Complicated Expansions of Solutions to ODES

    NASA Astrophysics Data System (ADS)

    Bruno, A. D.

    2018-03-01

    Polynomial ordinary differential equations are studied by asymptotic methods. The truncated equation associated with a vertex or a nonhorizontal edge of their polygon of the initial equation is assumed to have a solution containing the logarithm of the independent variable. It is shown that, under very weak constraints, this nonpower asymptotic form of solutions to the original equation can be extended to an asymptotic expansion of these solutions. This is an expansion in powers of the independent variable with coefficients being Laurent series in decreasing powers of the logarithm. Such expansions are sometimes called psi-series. Algorithms for such computations are described. Six examples are given. Four of them are concern with Painlevé equations. An unexpected property of these expansions is revealed.

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

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

    Zheng, Fasong; Departments of Physics, College of Science, Beijing University of Chemical Technology, Beijing 100029; Tan, Yidong

    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 surfacemore » 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.« less

  12. Assemblies and methods for mitigating effects of reactor pressure vessel expansion

    DOEpatents

    Challberg, Roy C.; Gou, Perng-Fei; Chu, Cherk Lam; Oliver, Robert P.

    1999-01-01

    Support assemblies for allowing RPV radial expansion while simultaneously limiting horizontal, vertical, and azimuthal movement of the RPV within a nuclear reactor are described. In one embodiment, the support assembly includes a support block and a guide block. The support block includes a first portion and a second portion, and the first portion is rigidly coupled to the RPV adjacent the first portion. The guide block is rigidly coupled to a reactor pressure vessel support structure and includes a channel sized to receive the second portion of the support block. The second portion of the support block is positioned in the guide block channel to movably couple the guide block to the support block.

  13. Assemblies and methods for mitigating effects of reactor pressure vessel expansion

    DOEpatents

    Challberg, R.C.; Gou, P.F.; Chu, C.L.; Oliver, R.P.

    1999-07-27

    Support assemblies for allowing RPV radial expansion while simultaneously limiting horizontal, vertical, and azimuthal movement of the RPV within a nuclear reactor are described. In one embodiment, the support assembly includes a support block and a guide block. The support block includes a first portion and a second portion, and the first portion is rigidly coupled to the RPV adjacent the first portion. The guide block is rigidly coupled to a reactor pressure vessel support structure and includes a channel sized to receive the second portion of the support block. The second portion of the support block is positioned in the guide block channel to movably couple the guide block to the support block. 6 figs.

  14. Secret-key expansion from covert communication

    NASA Astrophysics Data System (ADS)

    Arrazola, Juan Miguel; Amiri, Ryan

    2018-02-01

    Covert communication allows the transmission of messages in such a way that it is not possible for adversaries to detect that the communication is occurring. This provides protection in situations where knowledge that two parties are talking to each other may be incriminating to them. In this work, we study how covert communication can be used for a different purpose: secret key expansion. First, we show that any message transmitted in a secure covert protocol is also secret and therefore unknown to an adversary. We then propose a covert communication protocol where the amount of key consumed in the protocol is smaller than the transmitted key, thus leading to secure secret key expansion. We derive precise conditions for secret key expansion to occur, showing that it is possible when there are sufficiently low levels of noise for a given security level. We conclude by examining how secret key expansion from covert communication can be performed in a computational security model.

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

    PubMed Central

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

    2014-01-01

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

  16. The influence of interspecific interactions on species range expansion rates

    USGS Publications Warehouse

    Svenning, Jens-Christian; Gravel, Dominique; Holt, Robert D.; Schurr, Frank M.; Thuiller, Wilfried; Münkemüller, Tamara; Schiffers, Katja H.; Dullinger, Stefan; Edwards, Thomas C.; Hickler, Thomas; Higgins, Steven I.; Nabel, Julia E.M.S.; Pagel, Jörn; Normand, Signe

    2014-01-01

    Ongoing and predicted global change makes understanding and predicting species’ range shifts an urgent scientific priority. Here, we provide a synthetic perspective on the so far poorly understood effects of interspecific interactions on range expansion rates. We present theoretical foundations for how interspecific interactions may modulate range expansion rates, consider examples from empirical studies of biological invasions and natural range expansions as well as process-based simulations, and discuss how interspecific interactions can be more broadly represented in process-based, spatiotemporally explicit range forecasts. Theory tells us that interspecific interactions affect expansion rates via alteration of local population growth rates and spatial displacement rates, but also via effects on other demographic parameters. The best empirical evidence for interspecific effects on expansion rates comes from studies of biological invasions. Notably, invasion studies indicate that competitive dominance and release from specialized enemies can enhance expansion rates. Studies of natural range expansions especially point to the potential for competition from resident species to reduce expansion rates. Overall, it is clear that interspecific interactions may have important consequences for range dynamics, but also that their effects have received too little attention to robustly generalize on their importance. We then discuss how interspecific interactions effects can be more widely incorporated in dynamic modeling of range expansions. Importantly, models must describe spatiotemporal variation in both local population dynamics and dispersal. Finally, we derive the following guidelines for when it is particularly important to explicitly represent interspecific interactions in dynamic range expansion forecasts: if most interacting species show correlated spatial or temporal trends in their effects on the target species, if the number of interacting species is low

  17. The influence of interspecific interactions on species range expansion rates.

    PubMed

    Svenning, Jens-Christian; Gravel, Dominique; Holt, Robert D; Schurr, Frank M; Thuiller, Wilfried; Münkemüller, Tamara; Schiffers, Katja H; Dullinger, Stefan; Edwards, Thomas C; Hickler, Thomas; Higgins, Steven I; Nabel, Julia E M S; Pagel, Jörn; Normand, Signe

    2014-12-01

    Ongoing and predicted global change makes understanding and predicting species' range shifts an urgent scientific priority. Here, we provide a synthetic perspective on the so far poorly understood effects of interspecific interactions on range expansion rates. We present theoretical foundations for how interspecific interactions may modulate range expansion rates, consider examples from empirical studies of biological invasions and natural range expansions as well as process-based simulations, and discuss how interspecific interactions can be more broadly represented in process-based, spatiotemporally explicit range forecasts. Theory tells us that interspecific interactions affect expansion rates via alteration of local population growth rates and spatial displacement rates, but also via effects on other demographic parameters. The best empirical evidence for interspecific effects on expansion rates comes from studies of biological invasions. Notably, invasion studies indicate that competitive dominance and release from specialized enemies can enhance expansion rates. Studies of natural range expansions especially point to the potential for competition from resident species to reduce expansion rates. Overall, it is clear that interspecific interactions may have important consequences for range dynamics, but also that their effects have received too little attention to robustly generalize on their importance. We then discuss how interspecific interactions effects can be more widely incorporated in dynamic modeling of range expansions. Importantly, models must describe spatiotemporal variation in both local population dynamics and dispersal. Finally, we derive the following guidelines for when it is particularly important to explicitly represent interspecific interactions in dynamic range expansion forecasts: if most interacting species show correlated spatial or temporal trends in their effects on the target species, if the number of interacting species is low, and

  18. The influence of interspecific interactions on species range expansion rates

    PubMed Central

    Svenning, Jens-Christian; Gravel, Dominique; Holt, Robert D.; Schurr, Frank M.; Thuiller, Wilfried; Münkemüller, Tamara; Schiffers, Katja H.; Dullinger, Stefan; Edwards, Thomas C.; Hickler, Thomas; Higgins, Steven I.; Nabel, Julia E. M. S.; Pagel, Jörn; Normand, Signe

    2014-01-01

    Ongoing and predicted global change makes understanding and predicting species’ range shifts an urgent scientific priority. Here, we provide a synthetic perspective on the so far poorly understood effects of interspecific interactions on range expansion rates. We present theoretical foundations for how interspecific interactions may modulate range expansion rates, consider examples from empirical studies of biological invasions and natural range expansions as well as process-based simulations, and discuss how interspecific interactions can be more broadly represented in process-based, spatiotemporally explicit range forecasts. Theory tells us that interspecific interactions affect expansion rates via alteration of local population growth rates and spatial displacement rates, but also via effects on other demographic parameters. The best empirical evidence for interspecific effects on expansion rates comes from studies of biological invasions. Notably, invasion studies indicate that competitive dominance and release from specialized enemies can enhance expansion rates. Studies of natural range expansions especially point to the potential for competition from resident species to reduce expansion rates. Overall, it is clear that interspecific interactions may have important consequences for range dynamics, but also that their effects have received too little attention to robustly generalize on their importance. We then discuss how interspecific interactions effects can be more widely incorporated in dynamic modeling of range expansions. Importantly, models must describe spatiotemporal variation in both local population dynamics and dispersal. Finally, we derive the following guidelines for when it is particularly important to explicitly represent interspecific interactions in dynamic range expansion forecasts: if most interacting species show correlated spatial or temporal trends in their effects on the target species, if the number of interacting species is low

  19. Lessons from Early Medicaid Expansions Under Health Reform: Interviews with Medicaid Officials

    PubMed Central

    Sommers, Benjamin D; Arntson, Emily; Kenney, Genevieve M; Epstein, Arnold M

    2013-01-01

    Background The Affordable Care Act (ACA) dramatically expands Medicaid in 2014 in participating states. Meanwhile, six states have already expanded Medicaid since 2010 to some or all of the low-income adults targeted under health reform. We undertook an in-depth exploration of these six “early-expander” states—California, Connecticut, the District of Columbia, Minnesota, New Jersey, and Washington—through interviews with high-ranking Medicaid officials. Methods We conducted semi-structured interviews with 11 high-ranking Medicaid officials in six states and analyzed the interviews using qualitative methods. Interviews explored enrollment outreach, stakeholder involvement, impact on beneficiaries, utilization and costs, implementation challenges, and potential lessons for 2014. Two investigators independently analyzed interview transcripts and iteratively refined the codebook until reaching consensus. Results We identified several themes. First, these expansions built upon pre-existing state-funded insurance programs for the poor. Second, predictions about costs and enrollment were challenging, indicating the uncertainty in projections for 2014. Other themes included greater than anticipated need for behavioral health services in the expansion population, administrative challenges of expansions, and persistent barriers to enrollment and access after expanding eligibility—though officials overall felt the expansions increased access for beneficiaries. Finally, political context—support or opposition from stakeholders and voters—plays a critical role in shaping the success of Medicaid expansions. Conclusions Early Medicaid expansions under the ACA offer important lessons to federal and state policymakers as the 2014 expansions approach. While the context of each state’s expansion is unique, key shared experiences were significant implementation challenges and opportunities for expanding access to needed services. PMID:24834369

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

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

    Ranjbar, Ben; Kennedy, Brendan J.

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

  1. Periodontal evaluation in patients undergoing maxillary expansion.

    PubMed

    Carmen, M; Marcella, P; Giuseppe, C; Roberto, A

    2000-09-01

    Maxillary transverse diameter expansion is a treatment various authors have claimed is related to the development of gingival recession on the teeth of the upper arch. The aim of the present study was to compare such an incidence in two different groups of patients: those treated with surgically assisted rapid maxillary expansion and orthopedic expansion, respectively. Both treatments achieved the goal of expanding the transverse dimension (5.3 and 4.4 mm, respectively), but a significant difference was shown by the chi 2 test for the incidence of gingival recession of premolar/molar upper teeth, more than double for the latter than for the former. Therefore, surgically assisted rapid maxillary expansion seems to be an orthodontically effective procedure, safer than the orthopedic treatment regarding the possible development of mucogingival problems.

  2. Path-integral approach to the Wigner-Kirkwood expansion.

    PubMed

    Jizba, Petr; Zatloukal, Václav

    2014-01-01

    We study the high-temperature behavior of quantum-mechanical path integrals. Starting from the Feynman-Kac formula, we derive a functional representation of the Wigner-Kirkwood perturbation expansion for quantum Boltzmann densities. As shown by its applications to different potentials, the presented expansion turns out to be quite efficient in generating analytic form of the higher-order expansion coefficients. To put some flesh on the bare bones, we apply the expansion to obtain basic thermodynamic functions of the one-dimensional anharmonic oscillator. Further salient issues, such as generalization to the Bloch density matrix and comparison with the more customary world-line formulation, are discussed.

  3. Impact of DOTS expansion on tuberculosis related outcomes and costs in Haiti.

    PubMed

    Jacquet, Vary; Morose, Willy; Schwartzman, Kevin; Oxlade, Olivia; Barr, Graham; Grimard, Franque; Menzies, Dick

    2006-08-15

    Implementation of the World Health Organization's DOTS strategy (Directly Observed Treatment Short-course therapy) can result in significant reduction in tuberculosis incidence. We estimated potential costs and benefits of DOTS expansion in Haiti from the government, and societal perspectives. Using decision analysis incorporating multiple Markov processes (Markov modelling), we compared expected tuberculosis morbidity, mortality and costs in Haiti with DOTS expansion to reach all of the country, and achieve WHO benchmarks, or if the current situation did not change. Probabilities of tuberculosis related outcomes were derived from the published literature. Government health expenditures, patient and family costs were measured in direct surveys in Haiti and expressed in 2003 US$. Starting in 2003, DOTS expansion in Haiti is anticipated to cost $4.2 million and result in 63,080 fewer tuberculosis cases, 53,120 fewer tuberculosis deaths, and net societal savings of $131 million, over 20 years. Current government spending for tuberculosis is high, relative to the per capita income, and would be only slightly lower with DOTS. Societal savings would begin within 4 years, and would be substantial in all scenarios considered, including higher HIV seroprevalence or drug resistance, unchanged incidence following DOTS expansion, or doubling of initial and ongoing costs for DOTS expansion. A modest investment for DOTS expansion in Haiti would provide considerable humanitarian benefit by reducing tuberculosis-related morbidity, mortality and costs for patients and their families. These benefits, together with projected minimal Haitian government savings, argue strongly for donor support for DOTS expansion.

  4. Graphite fiber reinforced structure for supporting machine tools

    DOEpatents

    Knight, Jr., Charles E.; Kovach, Louis; Hurst, John S.

    1978-01-01

    Machine tools utilized in precision machine operations require tool support structures which exhibit minimal deflection, thermal expansion and vibration characteristics. The tool support structure of the present invention is a graphite fiber reinforced composite in which layers of the graphite fibers or yarn are disposed in a 0/90.degree. pattern and bonded together with an epoxy resin. The finished composite possesses a low coefficient of thermal expansion and a substantially greater elastic modulus, stiffness-to-weight ratio, and damping factor than a conventional steel tool support utilized in similar machining operations.

  5. 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

  6. 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,...

  7. Reaction-sintered porous mineral-based mullite ceramic membrane supports made from recycled materials.

    PubMed

    Dong, Yingchao; Zhou, Jian-Er; Lin, Bin; Wang, Yongqing; Wang, Songlin; Miao, Lifeng; Lang, Ying; Liu, Xingqin; Meng, Guangyao

    2009-12-15

    Bulk porous mullite supports for ceramic membranes were prepared directly using a mixture of industrial waste fly ash and bauxite by dry-pressing, followed by sintering between 1200 and 1550 degrees C. The effects of sintering temperature on the phase composition and shrinkage percent of porous mullite were studied. The XRD results indicate that secondary mullitization reaction took place above 1200 degrees C, and completed at 1450 degrees C. During sintering, the mixture samples first shrunk, then expanded abnormally between 1326 and 1477 degrees C, and finally shrunk again above 1477 degrees C. This unique volume self-expansion is ascribed to the secondary mullitization reaction between bauxite and fly ash. More especially, the micro-structural variations induced by this self-expansion sintering were verified by SEM, porosity, pore size distribution and nitrogen gas permeation flux. During self-expansion sintering, with increasing temperature, an abnormal increase in both open porosity and pore size is observed, which also results in the increase of nitrogen gas flux. The mineral-based mullite supports with increased open porosity were obtained. Furthermore, the sintered porous mullite membrane supports were characterized in terms of thermal expansion co-efficient and mechanical strength.

  8. The expansion of neighborhood and pattern formation on spatial prisoner's dilemma

    NASA Astrophysics Data System (ADS)

    Qian, Xiaolan; Xu, Fangqian; Yang, Junzhong; Kurths, Jürgen

    2015-04-01

    The prisoner's dilemma (PD), in which players can either cooperate or defect, is considered a paradigm for studying the evolution of cooperation in spatially structured populations. There the compact cooperator cluster is identified as a characteristic pattern and the probability of forming such pattern in turn depends on the features of the networks. In this paper, we investigate the influence of expansion of neighborhood on pattern formation by taking a weak PD game with one free parameter T, the temptation to defect. Two different expansion methods of neighborhood are considered. One is based on a square lattice and expanses along four directions generating networks with degree increasing with K = 4 m . The other is based on a lattice with Moore neighborhood and expanses along eight directions, generating networks with degree of K = 8 m . Individuals are placed on the nodes of the networks, interact with their neighbors and learn from the better one. We find that cooperator can survive for a broad degree 4 ≤ K ≤ 70 by taking a loose type of cooperator clusters. The former simple corresponding relationship between macroscopic patterns and the microscopic PD interactions is broken. Under a condition that is unfavorable for cooperators such as large T and K, systems prefer to evolve to a loose type of cooperator clusters to support cooperation. However, compared to the well-known compact pattern, it is a suboptimal strategy because it cannot help cooperators dominating the population and always corresponding to a low cooperation level.

  9. 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.

  10. Crank shaft support assembly

    DOEpatents

    Natkin, Robert J.; Oltmans, Bret; Allison, John E.; Heater, Thomas J.; Hines, Joy Adair; Tappen, Grant K.; Peiskammer, Dietmar

    2007-10-23

    A crank shaft support assembly for increasing stiffness and reducing thermal mismatch distortion in a crank shaft bore of an engine comprising different materials. A cylinder block comprises a first material and at least two crank journal inserts are insert-molded into respective crank journal regions of the cylinder block and comprise a second material having greater stiffness and a lower thermal coefficient of expansion that the first material. At least two bearing caps are bolted to the respective crank journal inserts and define, along with the crank journal inserts, at least two crank shaft support rings defining a crank shaft bore coaxially aligned with a crank shaft axis. The bearing caps comprise a material having higher stiffness and a lower thermal coefficient of expansion than the first material and are supported on the respective crank journal inserts independently of any direct connection to the cylinder block.

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

    PubMed

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

    2009-12-01

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

  12. Improvement of Expansive Soils Using Chemical Stabilizers

    NASA Astrophysics Data System (ADS)

    Ikizler, S. B.; Senol, A.; Khosrowshahi, S. K.; Hatipoğlu, M.

    2014-12-01

    The aim of this study is to investigate the effect of two chemical stabilizers on the swelling potential of expansive soil. A high plasticity sodium bentonite was used as the expansive soil. The additive materials including fly ash (FA) and lime (L) were evaluated as potential stabilizers to decrease the swelling pressure of bentonite. Depending on the type of additive materials, they were blended with bentonite in different percentages to assess the optimum state and approch the maximum swell pressure reduction. According to the results of swell pressure test, both fly ash and lime reduce the swelling potential of bentonite but the maximum improvement occurs using bentonite-lime mixture while the swelling pressure reduction approaches to 49%. The results reveal a significant reduction of swelling potential of expansive soil using chemical stabilizers. Keywords: Expansive soil; swell pressure; chemical stabilization; fly ash; lime

  13. Urban Expansion Modeling Approach Based on Multi-Agent System and Cellular Automata

    NASA Astrophysics Data System (ADS)

    Zeng, Y. N.; Yu, M. M.; Li, S. N.

    2018-04-01

    Urban expansion is a land-use change process that transforms non-urban land into urban land. This process results in the loss of natural vegetation and increase in impervious surfaces. Urban expansion also alters the hydrologic cycling, atmospheric circulation, and nutrient cycling processes and generates enormous environmental and social impacts. Urban expansion monitoring and modeling are crucial to understanding urban expansion process, mechanism, and its environmental impacts, and predicting urban expansion in future scenarios. Therefore, it is important to study urban expansion monitoring and modeling approaches. We proposed to simulate urban expansion by combining CA and MAS model. The proposed urban expansion model based on MSA and CA was applied to a case study area of Changsha-Zhuzhou-Xiangtan urban agglomeration, China. The results show that this model can capture urban expansion with good adaptability. The Kappa coefficient of the simulation results is 0.75, which indicated that the combination of MAS and CA offered the better simulation result.

  14. Gateway Arch Circulator Conceptual Feasibility Study : Jefferson National Expansion Memorial

    DOT National Transportation Integrated Search

    2015-03-01

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

  15. Thermal Expansion of Polyurethane Foam

    NASA Technical Reports Server (NTRS)

    Lerch, Bradley A.; Sullivan, Roy M.

    2006-01-01

    Closed cell foams are often used for thermal insulation. In the case of the Space Shuttle, the External Tank uses several thermal protection systems to maintain the temperature of the cryogenic fuels. A few of these systems are polyurethane, closed cell foams. In an attempt to better understand the foam behavior on the tank, we are in the process of developing and improving thermal-mechanical models for the foams. These models will start at the microstructural level and progress to the overall structural behavior of the foams on the tank. One of the key properties for model characterization and verification is thermal expansion. Since the foam is not a material, but a structure, the modeling of the expansion is complex. It is also exacerbated by the anisoptropy of the material. During the spraying and foaming process, the cells become elongated in the rise direction and this imparts different properties in the rise direction than in the transverse directions. Our approach is to treat the foam as a two part structure consisting of the polymeric cell structure and the gas inside the cells. The polymeric skeleton has a thermal expansion of its own which is derived from the basic polymer chemistry. However, a major contributor to the thermal expansion is the volume change associated with the gas inside of the closed cells. As this gas expands it exerts pressure on the cell walls and changes the shape and size of the cells. The amount that this occurs depends on the elastic and viscoplastic properties of the polymer skeleton. The more compliant the polymeric skeleton, the more influence the gas pressure has on the expansion. An additional influence on the expansion process is that the polymeric skeleton begins to breakdown at elevated temperatures and releases additional gas species into the cell interiors, adding to the gas pressure. The fact that this is such a complex process makes thermal expansion ideal for testing the models. This report focuses on the thermal

  16. Expansion: A Plan for Success.

    ERIC Educational Resources Information Center

    Callahan, A.P.

    This report provides selling brokers' guidelines for the successful expansion of their operations outlining a basic method of preparing an expansion plan. Topic headings are: The Pitfalls of Expansion (The Language of Business, Timely Financial Reporting, Regulatory Agencies of Government, Preoccupation with the Facade of Business, A Business Is a…

  17. Thermal expansion behavior study of Co nanowire array with in situ x-ray diffraction and x-ray absorption fine structure techniques

    NASA Astrophysics Data System (ADS)

    Mo, Guang; Cai, Quan; Jiang, Longsheng; Wang, Wei; Zhang, Kunhao; Cheng, Weidong; Xing, Xueqing; Chen, Zhongjun; Wu, Zhonghua

    2008-10-01

    In situ x-ray diffraction and x-ray absorption fine structure techniques were used to study the structural change of ordered Co nanowire array with temperature. The results show that the Co nanowires are polycrystalline with hexagonal close packed structure without phase change up until 700 °C. A nonlinear thermal expansion behavior has been found and can be well described by a quadratic equation with the first-order thermal expansion coefficient of 4.3×10-6/°C and the second-order thermal expansion coefficient of 5.9×10-9/°C. The mechanism of this nonlinear thermal expansion behavior is discussed.

  18. Reconstruction of Y-chromosome phylogeny reveals two neolithic expansions of Tibeto-Burman populations.

    PubMed

    Wang, Ling-Xiang; Lu, Yan; Zhang, Chao; Wei, Lan-Hai; Yan, Shi; Huang, Yun-Zhi; Wang, Chuan-Chao; Mallick, Swapan; Wen, Shao-Qing; Jin, Li; Xu, Shu-Hua; Li, Hui

    2018-06-19

    Diffusion of Tibeto-Burman populations across the Tibetan Plateau led to the largest human community in a high-altitude environment and has long been a focus of research on high-altitude adaptation, archeology, genetics, and linguistics. However, much uncertainty remains regarding the origin, diversification, and expansion of Tibeto-Burman populations. In this study, we analyzed a 7.0M bp region of 285 Y-chromosome sequences, including 81 newly reported ones, from male samples from Tibeto-Burman populations and other related Eastern Asian populations. We identified several paternal lineages specific to Tibeto-Burman populations, and most of these lineages emerged between 6000 and 2500 years ago. A phylogenetic tree and lineage dating both support the hypothesis that the establishment of Tibeto-Burman ancestral groups was triggered by Neolithic expansions from the middle Yellow River Basin and admixtures with local populations on the Tibetan Plateau who survived the Paleolithic Age. Furthermore, according to the geographical distributions of the haplogroups, we propose that there are two Neolithic expansion origins for all modern Tibeto-Burman populations. Our research provides a clear scenario about the sources, admixture process and later diffusion process of the ancestor population of all Tibeto-Burman populations.

  19. 48 CFR 570.403 - Expansion requests.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Continued Space Requirements 570.403 Expansion requests. (a) If the expansion space is in the general scope... justification under FAR 6.3. (b) If the expansion space needed is outside the general scope of the lease, the contracting officer must determine whether it is more prudent to provide the expansion space by supplemental...

  20. 48 CFR 570.403 - Expansion requests.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Continued Space Requirements 570.403 Expansion requests. (a) If the expansion space is in the general scope... FAR 6.3. (b) If the expansion space needed is outside the general scope of the lease, determine whether it is more prudent to provide the expansion space by supplemental agreement to the existing lease...

  1. 48 CFR 570.403 - Expansion requests.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Continued Space Requirements 570.403 Expansion requests. (a) If the expansion space is in the general scope... justification under FAR 6.3. (b) If the expansion space needed is outside the general scope of the lease, the contracting officer must determine whether it is more prudent to provide the expansion space by supplemental...

  2. 48 CFR 570.403 - Expansion requests.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Continued Space Requirements 570.403 Expansion requests. (a) If the expansion space is in the general scope... justification under FAR 6.3. (b) If the expansion space needed is outside the general scope of the lease, the contracting officer must determine whether it is more prudent to provide the expansion space by supplemental...

  3. 48 CFR 570.403 - Expansion requests.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Continued Space Requirements 570.403 Expansion requests. (a) If the expansion space is in the general scope... justification under FAR 6.3. (b) If the expansion space needed is outside the general scope of the lease, the contracting officer must determine whether it is more prudent to provide the expansion space by supplemental...

  4. Maxillary tridimensional changes after slow expansion with leaf expander in a sample of growing patients: a pilot study.

    PubMed

    Lanteri, V; Gianolio, A; Gualandi, G; Beretta, M

    2018-03-01

    The aim of this study is to evaluate the dento-alveolar effects of slow maxillary expansion using the Leaf Expander in a sample of growing patients with maxillary transverse deficiency, unilateral cross bite and mandibular shift. The study included 10 patients, 3 male and 7 female (mean age 7.5 + 7 months), treated with Leaf Expander anchored on the upper deciduous teeth. Digital models were obtained by a lab scan of the pvs impressions at the beginning of the therapy (T1) and at the removal of the palatal expander (T2). Five parameters were measured: 1) the distance between the first upper permanent molars; 2) the distance between the upper second deciduous molars; 3) the distance between the upper canine cusps 4) the distance between the first lower permanent molars; 5) the distance of the lower canine cusps. In all patients complete correction of posterior crossbite was achieved on average in 4 months, with a spontaneous expansion of the upper first permanent molars. Significant increases in the dento-alveolar transversal diameters were obtained. Increases were also observed in the anterior mandibular arch diameter (+ 1 mm). These findings suggest that slow maxillary expansion using Leaf Expander appliance could be a reasonable alternative to conventional maxillary expansion therapy in the early mixed dentition.

  5. Analysis of Biomechanical Effects of Different Sites and Modes of Orthodontic Loading On Arch Expansion in a Preadolescent Mandible: An FEA Study.

    PubMed

    Haresh, Ajmera Deepal; Pradeep, Singh; Song, Jinlin; Wang, Chao; Fan, Yubo

    2018-05-11

    The aim of commencing treatment in younger age is to rectify the developing dento-alveolar, skeletal and muscular imbalances. With growing dependence on arch development and expansion, the pendulum is oscillating more towards the non-extraction treatment lately, in resolving constriction and crowding issues. Since, a limited number of attempts have been made for mandibular expansion, this study aimes to evaluate the effect of different modes and sites of loading on the expansion of preadolescent mandible using biomechanics. To address the research purpose, a total of 9 Finite Element models were simulated. Biomechanical response of the mandibular bone and dentition was analyzed under different loading conditions including site and mode, using the simulated FE models. The values of displacement envisaged by the FE models, predict hybrid mode to offer substantial expansion of the mandibular bone as compared to tooth borne and bone borne. In addition, biomechanical effect of site II on mandibular expansion in terms of displacement on X-axis, was significant. In conclusion, the results of our study suggest hybrid mode at site II to be better option for true bony expansion in preadolescent mandible.

  6. Mapping Brazilian Cropland Expansion, 2000-2013

    NASA Astrophysics Data System (ADS)

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

    2016-12-01

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

  7. Attitudes of County Leaders toward Expanding Adult Programs in Extension: Minnesota Expansion Study I.

    ERIC Educational Resources Information Center

    Wilson, Duane A.; And Others

    A study was conducted in Minnesota on attitudes of county leaders (commissioners, auditors, and appointed Extension committee members) on ways of expanding Extension programs. In each county data were gathered by questionnaire from at least two thirds of the leaders. Questions were asked about expansion (1) through working with other…

  8. Parametric study of a simultaneous pitch/yaw thrust vectoring single expansion ramp nozzle

    NASA Technical Reports Server (NTRS)

    Schirmer, Alberto W.; Capone, Francis J.

    1989-01-01

    In the course of the last eleven years, the concept of thrust vectoring has emerged as a promising method of enhancing aircraft control capabilities in post-stall flight incursions during combat. In order to study the application of simultaneous pitch and yaw vectoring to single expansion ramp nozzles, a static test was conducted in the NASA-Langley 16 foot transonic tunnel. This investigation was based on internal performance data provided by force, mass flow and internal pressure measurements at nozzle pressure ratios up to 8. The internal performance characteristics of the nozzle were studied for several combinations of six different parameters: yaw vectoring angle, pitch vectoring angle, upper ramp cutout, sidewall hinge location, hinge inclination angle and sidewall containment. Results indicated a 2-to- 3-percent decrease in resultant thrust ratio with vectoring in either pitch or yaw. Losses were mostly associated with the turning of supersonic flow. Resultant thrust ratios were also decreased by sideways expansion of the jet. The effects of cutback corners in the upper ramp and lower flap on performance were small. Maximum resultant yaw vector angles, about half of the flap angle, were achieved for the configuration with the most forward hinge location.

  9. Bearing-Mounting Concept Accommodates Thermal Expansion

    NASA Technical Reports Server (NTRS)

    Nespodzany, Robert; Davis, Toren S.

    1995-01-01

    Pins or splines allow radial expansion without slippage. Design concept for mounting rotary bearing accommodates differential thermal expansion between bearing and any structure(s) to which bearing connected. Prevents buildup of thermal stresses by allowing thermal expansion to occur freely but accommodating expansion in such way not to introduce looseness. Pin-in-slot configuration also maintains concentricity.

  10. Screening a UK amyotrophic lateral sclerosis cohort provides evidence of multiple origins of the C9orf72 expansion.

    PubMed

    Fratta, Pietro; Polke, James M; Newcombe, Jia; Mizielinska, Sarah; Lashley, Tammaryn; Poulter, Mark; Beck, Jon; Preza, Elisavet; Devoy, Anny; Sidle, Katie; Howard, Robin; Malaspina, Andrea; Orrell, Richard W; Clarke, Jan; Lu, Ching-Hua; Mok, Kin; Collins, Toby; Shoaii, Maryam; Nanji, Tina; Wray, Selina; Adamson, Gary; Pittman, Alan; Renton, Alan E; Traynor, Bryan J; Sweeney, Mary G; Revesz, Tamas; Houlden, Henry; Mead, Simon; Isaacs, Adrian M; Fisher, Elizabeth M C

    2015-01-01

    An expanded hexanucleotide repeat in the C9orf72 gene is the most common genetic cause of amyotrophic lateral sclerosis and frontotemporal dementia (C9ALS/FTD). Although 0-30 hexanucleotide repeats are present in the general population, expansions >500 repeats are associated with C9ALS/FTD. Large C9ALS/FTD expansions share a common haplotype and whether these expansions derive from a single founder or occur more frequently on a predisposing haplotype is yet to be determined and is relevant to disease pathomechanisms. Furthermore, although cases carrying 50-200 repeats have been described, their role and the pathogenic threshold of the expansions remain to be identified and carry importance for diagnostics and genetic counseling. We present clinical and genetic data from a UK ALS cohort and report the detailed molecular study of an atypical somatically unstable expansion of 90 repeats. Our results across different tissues provide evidence for the pathogenicity of this repeat number by showing they can somatically expand in the central nervous system to the well characterized pathogenic range. Our results support the occurrence of multiple expansion events for C9ALS/FTD. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  11. Expansion Under Climate Change: The Genetic Consequences.

    PubMed

    Garnier, Jimmy; Lewis, Mark A

    2016-11-01

    Range expansion and range shifts are crucial population responses to climate change. Genetic consequences are not well understood but are clearly coupled to ecological dynamics that, in turn, are driven by shifting climate conditions. We model a population with a deterministic reaction-diffusion model coupled to a heterogeneous environment that develops in time due to climate change. We decompose the resulting travelling wave solution into neutral genetic components to analyse the spatio-temporal dynamics of its genetic structure. Our analysis shows that range expansions and range shifts under slow climate change preserve genetic diversity. This is because slow climate change creates range boundaries that promote spatial mixing of genetic components. Mathematically, the mixing leads to so-called pushed travelling wave solutions. This mixing phenomenon is not seen in spatially homogeneous environments, where range expansion reduces genetic diversity through gene surfing arising from pulled travelling wave solutions. However, the preservation of diversity is diminished when climate change occurs too quickly. Using diversity indices, we show that fast expansions and range shifts erode genetic diversity more than slow range expansions and range shifts. Our study provides analytical insight into the dynamics of travelling wave solutions in heterogeneous environments.

  12. 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.

  13. Micromechanics investigation of expansive reactions in chemoelastic concrete.

    PubMed

    Lemarchand, Eric; Dormieux, Luc; Ulm, Franz-Josef

    2005-11-15

    Expansive reactions damage porous materials through the formation of reaction products of a volume in excess of the available space left by the reactants and the natural porosity of the material. This leads to pressurizing the pore space accessible to the reaction products, which differs when the chemical reaction is through-solution or topochemical or both in nature. This paper investigates expansive reactions from a micromechanical point of view, which allows bridging the scale from the local chemo-mechanical mechanisms to the macroscopically observable stress-free expansion. In particular, the study of the effect of morphology of the pore space, in which the chemical expansion occurs locally, on the macroscopically observable expansion is the main focus of this paper. The first part revisits the through-solution and the topochemical reaction mechanism within the framework of micro-macro-homogenization theories, and the effect of the microscopic geometry of pores and microcracks in the solid matrix on the macroscopic chemical expansion is examined. The second part deals with the transition from a topochemical to a through-solution-like mechanism that occurs in a solid matrix with inclusions (cracks, pores) of different morphology.

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

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

    Conzelmann, G.; Koritarov, V.; Buehring, W.

    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 analysismore » 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

  15. Identification of invasive and expansive plant species based on airborne hyperspectral and ALS data

    NASA Astrophysics Data System (ADS)

    Szporak-Wasilewska, Sylwia; Kuc, Gabriela; Jóźwiak, Jacek; Demarchi, Luca; Chormański, Jarosław; Marcinkowska-Ochtyra, Adriana; Ochtyra, Adrian; Jarocińska, Anna; Sabat, Anita; Zagajewski, Bogdan; Tokarska-Guzik, Barbara; Bzdęga, Katarzyna; Pasierbiński, Andrzej; Fojcik, Barbara; Jędrzejczyk-Korycińska, Monika; Kopeć, Dominik; Wylazłowska, Justyna; Woziwoda, Beata; Michalska-Hejduk, Dorota; Halladin-Dąbrowska, Anna

    2017-04-01

    The aim of Natura 2000 network is to ensure the long term survival of most valuable and threatened species and habitats in Europe. The encroachment of invasive alien and expansive native plant species is among the most essential threat that can cause significant damage to protected habitats and their biodiversity. The phenomenon requires comprehensive and efficient repeatable solutions that can be applied to various areas in order to assess the impact on habitats. The aim of this study is to investigate of the issue of invasive and expansive plant species as they affect protected areas at a larger scale of Natura 2000 network in Poland. In order to determine the scale of the problem we have been developing methods of identification of invasive and expansive species and then detecting their occurrence and mapping their distribution in selected protected areas within Natura 2000 network using airborne hyperspectral and airborne laser scanning data. The aerial platform used consists of hyperspectral HySpex scanner (451 bands in VNIR and SWIR), Airborne Laser Scanner (FWF) Riegl Lite Mapper and RGB camera. It allowed to obtain simultaneous 1 meter resolution hyperspectral image, 0.1 m resolution orthophotomaps and point cloud data acquired with 7 points/m2. Airborne images were acquired three times per year during growing season to account for plant seasonal change (in May/June, July/August and September/October 2016). The hyperspectral images were radiometrically, geometrically and atmospherically corrected. Atmospheric correction was performed and validated using ASD FieldSpec 4 measurements. ALS point cloud data were used to generate several different topographic, vegetation and intensity products with 1 m spatial resolution. Acquired data (both hyperspectral and ALS) were used to test different classification methods including Mixture Tuned Matched Filtering (MTMF), Spectral Angle Mapper (SAM), Random Forest (RF), Support Vector Machines (SVM), among others

  16. Visible-Light Photocatalytic Intramolecular Cyclopropane Ring Expansion.

    PubMed

    Luis-Barrera, Javier; Laina-Martín, Víctor; Rigotti, Thomas; Peccati, Francesca; Solans-Monfort, Xavier; Sodupe, Mariona; Mas-Ballesté, Rubén; Liras, Marta; Alemán, José

    2017-06-26

    Described herein is a new visible-light photocatalytic strategy for the synthesis of enantioenriched dihydrofurans and cyclopentenes by an intramolecular nitro cyclopropane ring expansion reaction. Mechanistic studies and DFT calculations are used to elucidate the key factors in this new ring expansion reaction, and the need for the nitro group on the cyclopropane. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Hominin expansion into Central Asia during the last interglacial

    NASA Astrophysics Data System (ADS)

    Asmerom, Yemane; Polyak, Victor J.; Wagner, Jennifer D. M.; Jonathan Patchett, P.

    2018-07-01

    Central Asia was a likely gateway for hominin expansion. Obi-Rakhmat Grotto, northeastern Uzbekistan, has a deposit that contains the remains of a hominin child (OR-1) and more than 60,000 Paleolithic artifacts, making it one of the most important archaeological sites in Central Asia. Regionally, genetic data suggest hominin presence and human-Neanderthal interbreeding as far back as 100 ka, although, to date, absolute ages of hominin remains that old have not been known in the region. We present new uranium-series dates that constrain the age of the Obi-Rakhmat deposit to 98 ka towards the top and 109 ka for the layer containing OR-1, pushing hominin expansion into Central Asia minimally to 109 ± 2 ka, to a time, based on the genetic clock, of Neanderthal-modern human interbreeding. Our chronology establishes a minimum age of 98 ka for the well-developed lithic industry in Central Asia. The period covering the deposition of the sediments containing the artifacts and specimen OR-1 coincides with a warm and one of the most humid intervals of Marine Isotope Stage (MIS) 5 and last glacial period in the region, providing support for climate-driven hominin expansion.

  18. Community Health Center Utilization Following the 2008 Medicaid Expansion in Oregon: Implications for the Affordable Care Act.

    PubMed

    Hatch, Brigit; Bailey, Steffani R; Cowburn, Stuart; Marino, Miguel; Angier, Heather; DeVoe, Jennifer E

    2016-04-01

    To assess longitudinal patterns of community health center (CHC) utilization and the effect of insurance discontinuity after Oregon's 2008 Medicaid expansion (the Oregon Experiment). We conducted a retrospective cohort study with electronic health records and Medicaid data. We divided individuals who gained Medicaid in the Oregon Experiment into those who maintained (n = 788) or lost (n = 944) insurance coverage. We compared these groups with continuously insured (n = 921) and continuously uninsured (n = 5416) reference groups for community health center utilization rates over a 36-month period. Both newly insured groups increased utilization in the first 6 months. After 6 months, use among those who maintained coverage stabilized at a level consistent with the continuously insured, whereas it returned to baseline for those who lost coverage. Individuals who maintained coverage through Oregon's Medicaid expansion increased long-term utilization of CHCs, whereas those with unstable coverage did not. This study predicts long-term increase in CHC utilization following Affordable Care Act Medicaid expansion and emphasizes the need for policies that support insurance retention.

  19. Public insurance expansions and crowd out of private coverage.

    PubMed

    Marquis, M Susan; Long, Stephen H

    2003-03-01

    The extent to which persons enrolling in new public insurance programs substitute the public coverage for private insurance is of concern to policy makers. To look at the extent of the substitution resulting from new state programs that cover a broad base of the low-income population and to look at the responses of both families and employers. The March CPS for 1991-1993 and 1997-1998 were used to study the responses of families. Two large national surveys of employers with information about the employment-based system in 1993 and 1997 were used to study employer responses. The analysis looks at changes in coverage and employer offer rates before and after the public insurance expansions in selected states and compares these changes to those in a control group in states without expansions. Coverage by private insurance for low-income persons in states with expansions fell by more than expected based on the control states, indicating some substitution of public coverage for private insurance. Changes in employee coverage in own-employer sponsored insurance accord with this result. The expansion of public insurance has a bigger effect on employer offer decisions when a large share of its workers is eligible for public programs. The results show a significant substitution of public insurance for private coverage in the expansions studied. However, endogeneity of state expansion policies and possible confounding with other policy changes temper the conclusions. More recent public insurance expansions as part of the State Childrens' Health Insurance Program have adopted a range of methods to limit crowd out. Future research is needed to evaluate whether these procedures and rules have succeeded.

  20. Nonlinear effects on composite laminate thermal expansion

    NASA Technical Reports Server (NTRS)

    Hashin, Z.; Rosen, B. W.; Pipes, R. B.

    1979-01-01

    Analyses of Graphite/Polyimide laminates shown that the thermomechanical strains cannot be separated into mechanical strain and free thermal expansion strain. Elastic properties and thermal expansion coefficients of unidirectional Graphite/Polyimide specimens were measured as a function of temperature to provide inputs for the analysis. The + or - 45 degrees symmetric Graphite/Polyimide laminates were tested to obtain free thermal expansion coefficients and thermal expansion coefficients under various uniaxial loads. The experimental results demonstrated the effects predicted by the analysis, namely dependence of thermal expansion coefficients on load, and anisotropy of thermal expansion under load. The significance of time dependence on thermal expansion was demonstrated by comparison of measured laminate free expansion coefficients with and without 15 day delay at intermediate temperature.

  1. C9ORF72 hexanucleotide repeat expansions are a frequent cause of Huntington disease phenocopies in the Greek population.

    PubMed

    Koutsis, Georgios; Karadima, Georgia; Kartanou, Chrisoula; Kladi, Athina; Panas, Marios

    2015-01-01

    An expanded hexanucleotide repeat in C9ORF72 has been identified as the most common genetic cause of amyotrophic lateral sclerosis and/or frontotemporal dementia in many populations, including the Greek. Recently, C9ORF72 expansions were reported as the most common genetic cause of Huntington disease (HD) phenocopies in a UK population. In the present study, we screened a selected cohort of 40 Greek patients with HD phenocopies for C9ORF72 hexanucleotide repeat expansions using repeat-primed polymerase chain reaction. We identified 2 patients (5%) with pathologic expansions. The first patient had chorea, behavioral-psychiatric disturbance, cognitive impairment, and a positive family history, fulfilling the strictest criteria for HD phenocopy. The second patient was sporadic and had parkinsonism, behavioral-psychiatric disturbance, and cognitive impairment, corresponding to a broader definition of HD phenocopy. These findings identify C9ORF72 expansions as a frequent cause of HD phenocopies in the Greek population, confirming recent findings in other populations and supporting proposed diagnostic testing for C9ORF72 expansions in patients with HD-like syndromes. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. An X-ray Expansion and Proper Motion Study of the Magellanic Cloud Supernova Remnant J0509-6731 with the Chandra X-ray Observatory

    NASA Astrophysics Data System (ADS)

    Roper, Quentin; Filipovi, Miroslav; Allen, Glenn E.; Sano, Hidetoshi; Park, Laurence; Pannuti, Thomas G.; Sasaki, Manami; Haberl, Frank; Kavanagh, Patrick J.; Yamane, Yumiko; Yoshiike, Satoshi; Fujii, Kosuke; Fukui, Yasuo; Seitenzahl, Ivo R.

    2018-05-01

    Using archival Chandra data consisting of a total of 78.46 ksec over two epochs seven years apart, we have measured the expansion of the young (˜400 years old) type Ia Large Magellanic Cloud supernova remnant (SNR) J0509-6731. In addition, we use radial brightness profile matching to detect proper-motion expansion of this SNR, and estimate an speed of 7 500±1 700 km s-1. This is one of the only proper motion studies of extragalactic SNRs expansion that is able to derive an expansion velocity, and one of only two such studies of an extragalactic SNR to yield positive results in the X-rays. We find that this expansion velocity is consistent with an optical expansion study on this object. In addition, we examine the medium into which the SNR is expanding by examining the CO and neutral H I gas using radio data obtained from Mopra, the Australia Telescope Compact Array and Parkes radio telescopes. We also briefly compare this result with a recent radio survey, and find that our results predict a radio spectral index α of -0.67±0.07. This value is consistent with high frequency radio observations of MCSNR J0509-6731.

  3. Volume of Plasma Expansion and Functional Outcomes in Stroke.

    PubMed

    Miller, Joseph B; Lewandowski, Christopher; Wira, Charles R; Taylor, Andrew; Burmeister, Charlotte; Welch, Robert

    2017-04-01

    Plasma expansion in acute ischemic stroke has potential to improve cerebral perfusion, but the long-term effects on functional outcome are mixed in prior trials. The goal of this study was to evaluate how the magnitude of plasma expansion affects neurological recovery in acute stroke. This was a secondary analysis of data from the Albumin in Acute Stroke Part 2 trial investigating the relationship between the magnitude of overall intravenous volume infusion (crystalloid and colloid) to clinical outcome. The data were inclusive of 841 patients with a mean age of 64 years and a median National Institutes of Health Stroke Scale (NIHSS) of 11. In a multivariable-adjusted logistic regression model, this analysis tested the volume of plasma expansion over the first 48 h of hospitalization as a predictor of favorable outcome, defined as either a modified Rankin Scale score of 0 or 1 or a NIHSS score of 0 or 1 at 90 days. This model included all study patients, irrespective of albumin or isotonic saline treatment. Patients that received higher volumes of plasma expansion more frequently had large vessel ischemic stroke and higher NIHSS scores. The multivariable-adjusted model revealed that there was decreased odds of a favorable outcome for every 250 ml additional volume plasma expansion over the first 48 h (OR 0.91, 95 % CI, 0.88-0.94). The present study demonstrates an association between greater volume of plasma expansion and worse neurological recovery.

  4. 78 FR 24208 - Announcement of the Award of 12 Single-Source Program Expansion Supplement Grants to...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-24

    ... Unaccompanied Alien Children's Shelter Care Grantees AGENCY: Office of Refugee Resettlement, Administration for... services to the increasing number of unaccompanied alien children. SUMMARY: The Administration for Children... support the expansion of bed capacity and supportive services to meet the number of unaccompanied alien...

  5. The Effects of Expansions, Questions and Cloze Procedures on Children's Conversational Skills

    ERIC Educational Resources Information Center

    Wong, Tze-Peng; Moran, Catherine; Foster-Cohen, Susan

    2012-01-01

    The effectiveness of expansion as a technique for facilitating children's language and conversational skills is well known (Scherer and Olswang, 1984). Expansion, however, can appear alone or in combination with other techniques. Using a repeated measures design, this study aimed to compare the effects of expansion alone (EA); expansion combined…

  6. Lightweight Mechanical Metamaterials with Tunable Negative Thermal Expansion

    NASA Astrophysics Data System (ADS)

    Wang, Qiming; Jackson, Julie A.; Ge, Qi; Hopkins, Jonathan B.; Spadaccini, Christopher M.; Fang, Nicholas X.

    2016-10-01

    Ice floating on water is a great manifestation of negative thermal expansion (NTE) in nature. The limited examples of natural materials possessing NTE have stimulated research on engineered structures. Previous studies on NTE structures were mostly focused on theoretical design with limited experimental demonstration in two-dimensional planar geometries. In this work, aided with multimaterial projection microstereolithography, we experimentally fabricate lightweight multimaterial lattices that exhibit significant negative thermal expansion in three directions and over a temperature range of 170 degrees. Such NTE is induced by the structural interaction of material components with distinct thermal expansion coefficients. The NTE can be tuned over a large range by varying the thermal expansion coefficient difference between constituent beams and geometrical arrangements. Our experimental results match qualitatively with a simple scaling law and quantitatively with computational models.

  7. Compressive Sensing Cluster Expansion Studies of Lithium Intercalation and Phase Transformation in MoS2 for Energy Storage

    NASA Astrophysics Data System (ADS)

    Liu, Chi-Ping; Zhou, Fei; Ozolins, Vidvuds; University of California, Los Angeles Collaboration; Lawrence livermore national laboratory Collaboration

    2015-03-01

    Bulk molybdenum disulfide (MoS2) is a good electrode material candidate for energy storage applications, such as lithium ion batteries and supercapacitors due to its high theoretical energy and power density. First-principles density-functional theory (DFT) calculations combined with cluster expansion are an effective method to study thermodynamic and kinetic properties of electrode materials. In order to construct accurate models for cluster expansion, it is important to effectively choose clusters with significant contributions. In this work, we employ a compressive sensing based technique to select relevant clusters in order to build an accurate Hamiltonian for cluster expansion, enabling the study of Li intercalation in MoS2. We find that the 2H MoS2 structure is only stable at low Li content while 1T MoS2 is the preferred phase at high Li content. The results show that the 2H MoS2 phase transforms into the disordered 1T phase and the disordered 1T structure remains after the first Li insertion/deinsertion cycle suggesting that disordered 1T MoS2 is stable even at dilute Li content. This work also highlights that cluster expansion treated with compressive sensing is an effective and powerful tool for model construction and can be applied to advanced battery and supercapacitor electrode materials.

  8. Central venous pressure and shock index predict lack of hemodynamic response to volume expansion in septic shock: a prospective, observational study.

    PubMed

    Lanspa, Michael J; Brown, Samuel M; Hirshberg, Eliotte L; Jones, Jason P; Grissom, Colin K

    2012-12-01

    Volume expansion is a common therapeutic intervention in septic shock, although patient response to the intervention is difficult to predict. Central venous pressure (CVP) and shock index have been used independently to guide volume expansion, although their use is questionable. We hypothesize that a combination of these measurements will be useful. In a prospective, observational study, patients with early septic shock received 10-mL/kg volume expansion at their treating physician's discretion after brief initial resuscitation in the emergency department. Central venous pressure and shock index were measured before volume expansion interventions. Cardiac index was measured immediately before and after the volume expansion using transthoracic echocardiography. Hemodynamic response was defined as an increase in a cardiac index of 15% or greater. Thirty-four volume expansions were observed in 25 patients. A CVP of 8 mm Hg or greater and a shock index of 1 beat min(-1) mm Hg(-1) or less individually had a good negative predictive value (83% and 88%, respectively). Of 34 volume expansions, the combination of both a high CVP and a low shock index was extremely unlikely to elicit hemodynamic response (negative predictive value, 93%; P = .02). Volume expansion in patients with early septic shock with a CVP of 8 mm Hg or greater and a shock index of 1 beat min(-1) mm Hg(-1) or less is unlikely to lead to an increase in cardiac index. Copyright © 2012 Elsevier Inc. All rights reserved.

  9. One-stage sequential bilateral thoracic expansion for asphyxiating thoracic dystrophy (Jeune syndrome).

    PubMed

    Muthialu, Nagarajan; Mussa, Shafi; Owens, Catherine M; Bulstrode, Neil; Elliott, Martin J

    2014-10-01

    Jeune syndrome (asphyxiating thoracic dystrophy) is a rare disorder characterized by skeletal dysplasia, reduced diameter of the thoracic cage and extrathoracic organ involvement. Fatal, early respiratory insufficiency may occur. Two-stage lateral thoracic expansion has been reported, addressing each side sequentially over 3-12 months. While staged repair theoretically provides less invasive surgery in a small child with respiratory distress, we utilized a single stage, bilateral procedure aiming to rapidly maximize lung development. Combined bilateral surgery also offered the chance of rapid recovery, and reduced hospital stay. We present our early experience of this modification of existing surgical treatment for an extremely rare condition, thought to be generally fatal in early childhood. Nine children (6 males, 3 females; median age 30 months [3.5-75]) underwent thoracic expansion for Jeune syndrome in our centre. All patients required preoperative respiratory support (5 with tracheostomy, 8 requiring positive pressure ventilation regularly within each day/night cycle). Two children underwent sequential unilateral (2-month interval between stages) and 7 children bilateral thoracic expansion by means of staggered osteotomies of third to eighth ribs and plate fixation of fourth to fifth rib and sixth to seventh rib, leaving the remaining ribs floating. There was no operative mortality. There were 2 deaths within 3 months of surgery, due to pulmonary hypertension (1 following two-stage and 1 following single-stage thoracic expansion). At the median follow-up of 11 months (1-15), 3 children have been discharged home from their referring unit and 2 have significantly reduced respiratory support. One child remains on non-invasive ventilation and another is still ventilated with a high oxygen requirement. Jeune syndrome is a difficult condition to manage, but bilateral thoracic expansion offers an effective reduction in ventilator requirements in these children

  10. A computational study of crimping and expansion of bioresorbable polymeric stents

    NASA Astrophysics Data System (ADS)

    Qiu, T. Y.; Song, M.; Zhao, L. G.

    2018-05-01

    This paper studied the mechanical performance of four bioresorbable PLLA stents, i.e., Absorb, Elixir, Igaki-Tamai and RevaMedical, during crimping and expansion using the finite element method. Abaqus CAE was used to create the geometrical models for the four stents. A tri-folded balloon was created using NX software. For the stents, elastic-plastic behaviour was used, with hardening implemented by considering the increase of yield stress with the plastic strain. The tri-folded balloon was treated as linear elastic. To simulate the crimping of stents, a set of 12 rigid plates were generated around the stents with a radially enforced displacement. During crimping, the stents were compressed from a diameter of 3 mm to 1.2 mm, with the maximum stress developed at both inner and outer sides of the U-bends. During expansion, the stent inner diameter increased to 3 mm at the peak pressure and then recoiled to different final diameters after balloon deflation due to different stent designs. The maximum stress was found again at the U-bends of stents. Diameter change, recoiling effect and radial strength/stiffness were also compared for the four stents to assess the effect of design variation on stent performance. The effect of loading rate on stent deformation was also simulated by considering the time-dependent plastic behaviour of polymeric material.

  11. A computational study of crimping and expansion of bioresorbable polymeric stents

    NASA Astrophysics Data System (ADS)

    Qiu, T. Y.; Song, M.; Zhao, L. G.

    2017-10-01

    This paper studied the mechanical performance of four bioresorbable PLLA stents, i.e., Absorb, Elixir, Igaki-Tamai and RevaMedical, during crimping and expansion using the finite element method. Abaqus CAE was used to create the geometrical models for the four stents. A tri-folded balloon was created using NX software. For the stents, elastic-plastic behaviour was used, with hardening implemented by considering the increase of yield stress with the plastic strain. The tri-folded balloon was treated as linear elastic. To simulate the crimping of stents, a set of 12 rigid plates were generated around the stents with a radially enforced displacement. During crimping, the stents were compressed from a diameter of 3 mm to 1.2 mm, with the maximum stress developed at both inner and outer sides of the U-bends. During expansion, the stent inner diameter increased to 3 mm at the peak pressure and then recoiled to different final diameters after balloon deflation due to different stent designs. The maximum stress was found again at the U-bends of stents. Diameter change, recoiling effect and radial strength/stiffness were also compared for the four stents to assess the effect of design variation on stent performance. The effect of loading rate on stent deformation was also simulated by considering the time-dependent plastic behaviour of polymeric material.

  12. Facilitating Expansive Learning in a Public Sector Organization

    ERIC Educational Resources Information Center

    Gustavsson, Maria

    2009-01-01

    The aim of this article is to discuss how learning opportunities can be organized to promote expansive learning in work practice. The discussion draws on results from a case study examining local development work and conditions that facilitate processes of expansive learning in a work team within a public sector organization in a Swedish…

  13. A Meta-Analysis of Global Urban Land Expansion

    PubMed Central

    Seto, Karen C.; Fragkias, Michail; Güneralp, Burak; Reilly, Michael K.

    2011-01-01

    The conversion of Earth's land surface to urban uses is one of the most irreversible human impacts on the global biosphere. It drives the loss of farmland, affects local climate, fragments habitats, and threatens biodiversity. Here we present a meta-analysis of 326 studies that have used remotely sensed images to map urban land conversion. We report a worldwide observed increase in urban land area of 58,000 km2 from 1970 to 2000. India, China, and Africa have experienced the highest rates of urban land expansion, and the largest change in total urban extent has occurred in North America. Across all regions and for all three decades, urban land expansion rates are higher than or equal to urban population growth rates, suggesting that urban growth is becoming more expansive than compact. Annual growth in GDP per capita drives approximately half of the observed urban land expansion in China but only moderately affects urban expansion in India and Africa, where urban land expansion is driven more by urban population growth. In high income countries, rates of urban land expansion are slower and increasingly related to GDP growth. However, in North America, population growth contributes more to urban expansion than it does in Europe. Much of the observed variation in urban expansion was not captured by either population, GDP, or other variables in the model. This suggests that contemporary urban expansion is related to a variety of factors difficult to observe comprehensively at the global level, including international capital flows, the informal economy, land use policy, and generalized transport costs. Using the results from the global model, we develop forecasts for new urban land cover using SRES Scenarios. Our results show that by 2030, global urban land cover will increase between 430,000 km2 and 12,568,000 km2, with an estimate of 1,527,000 km2 more likely. PMID:21876770

  14. Support for smoking cessation interventions in physician organizations: results from a national study.

    PubMed

    McMenamin, Sara B; Schauffler, Helen Halpin; Shortell, Stephen M; Rundall, Thomas G; Gillies, Robin R

    2003-12-01

    To document the extent to which physician organizations, defined as medical groups and independent practice associations, are providing support for smoking cessation interventions and to identify external incentives and organizational characteristics associated with this support. This research uses data from the National Study of Physician Organizations and the Management of Chronic Illness, conducted by the University of California at Berkeley, to document the extent to which physician organizations provide support for smoking cessation interventions. Of 1587 physician organizations nationally with 20 or more physicians, 1104 participated, for a response rate of 70%. Overall, 70% of physician organizations offered some support for smoking cessation interventions. Specifically, 17% require physicians to provide interventions, 15% evaluate interventions, 39% of physician organizations offer smoking health promotion programs, 25% provide nicotine replacement therapy starter kits, and materials are provided on pharmacotherapy (39%), counseling (37%), and self-help (58%). Factors positively associated with organizational support include income or public recognition for quality measures, financial incentives to promote smoking cessation interventions, requirements to report HEDIS (Health Plan Employer Data and Information Set) scores, awareness of the 1996 Clinical Practice Guideline on Smoking Cessation, being a medical group, organizational size, percentage of primary care physicians, and hospital/HMO ownership of the organization. Physician organizations are providing support for smoking cessation interventions, yet the level of support might be improved with more extensive use of external incentives. Financial incentives targeted specifically at promoting smoking cessation interventions need to be explored further. Additionally, emphasis on quality measures should continue, including an expansion of HEDIS smoking cessation measures.

  15. 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…

  16. Simplified Technique for Predicting Offshore Pipeline Expansion

    NASA Astrophysics Data System (ADS)

    Seo, J. H.; Kim, D. K.; Choi, H. S.; Yu, S. Y.; Park, K. S.

    2018-06-01

    In this study, we propose a method for estimating the amount of expansion that occurs in subsea pipelines, which could be applied in the design of robust structures that transport oil and gas from offshore wells. We begin with a literature review and general discussion of existing estimation methods and terminologies with respect to subsea pipelines. Due to the effects of high pressure and high temperature, the production of fluid from offshore wells is typically caused by physical deformation of subsea structures, e.g., expansion and contraction during the transportation process. In severe cases, vertical and lateral buckling occurs, which causes a significant negative impact on structural safety, and which is related to on-bottom stability, free-span, structural collapse, and many other factors. In addition, these factors may affect the production rate with respect to flow assurance, wax, and hydration, to name a few. In this study, we developed a simple and efficient method for generating a reliable pipe expansion design in the early stage, which can lead to savings in both cost and computation time. As such, in this paper, we propose an applicable diagram, which we call the standard dimensionless ratio (SDR) versus virtual anchor length (L A ) diagram, that utilizes an efficient procedure for estimating subsea pipeline expansion based on applied reliable scenarios. With this user guideline, offshore pipeline structural designers can reliably determine the amount of subsea pipeline expansion and the obtained results will also be useful for the installation, design, and maintenance of the subsea pipeline.

  17. Contribution of future urbanisation expansion to flood risk changes

    NASA Astrophysics Data System (ADS)

    Bruwier, Martin; Mustafa, Ahmed; Archambeau, Pierre; Erpicum, Sébastien; Pirotton, Michel; Teller, Jacques; Dewals, Benjamin

    2016-04-01

    The flood risk is expected to increase in the future due to climate change and urban development. Climate change modifies flood hazard and urban development influences exposure and vulnerability to floods. While the influence of climate change on flood risk has been studied widely, the impact of urban development also needs to be considered in a sustainable flood risk management approach. The main goal of this study is the determination of the sensitivity of future flood risk to different urban development scenarios at a relatively short-time horizon in the River Meuse basin in Wallonia (Belgium). From the different scenarios, the expected impact of urban development on flood risk is assessed. Three urban expansion scenarios are developed up to 2030 based on a coupled cellular automata (CA) and agent-based (AB) urban expansion model: (i) business-as-usual, (ii) restrictive and (iii) extreme expansion scenarios. The main factor controlling these scenarios is the future urban land demand. Each urban expansion scenario is developed by considering or not high and/or medium flood hazard zones as a constraint for urban development. To assess the model's performance, it is calibrated for the Meuse River valley (Belgium) to simulate urban expansion between 1990 and 2000. Calibration results are then assessed by comparing the 2000 simulated land-use map and the actual 2000 land-use map. The flood damage estimation for each urban expansion scenario is determined for five flood discharges by overlaying the inundation map resulting from a hydraulic computation and the urban expansion map and by using damage curves and specific prices. The hydraulic model Wolf2D has been extensively validated by comparisons between observations and computational results during flood event .This study focuses only on mobile and immobile prices for urban lands, which are associated to the most severe damages caused by floods along the River Meuse. These findings of this study offers tools to

  18. Iterative expansion microscopy

    PubMed Central

    Chang, Jae-Byum; Chen, Fei; Yoon, Young-Gyu; Jung, Erica E.; Babcock, Hazen; Kang, Jeong Seuk; Asano, Shoh; Suk, Ho-Jun; Pak, Nikita; Tillberg, Paul W.; Wassie, Asmamaw; Cai, Dawen; Boyden, Edward S.

    2017-01-01

    We recently discovered it was possible to physically magnify preserved biological specimens by embedding them in a densely crosslinked polyelectrolyte gel, anchoring key labels or biomolecules to the gel, mechanically homogenizing the specimen, and then swelling the gel-specimen composite by ~4.5x in linear dimension, a process we call expansion microscopy (ExM). Here we describe iterative expansion microscopy (iExM), in which a sample is expanded, then a second swellable polymer mesh is formed in the space newly opened up by the first expansion, and finally the sample is expanded again. iExM expands biological specimens ~4.5 × 4.5 or ~20x, and enables ~25 nm resolution imaging of cells and tissues on conventional microscopes. We used iExM to visualize synaptic proteins, as well as the detailed architecture of dendritic spines, in mouse brain circuitry. PMID:28417997

  19. Engineered artificial antigen presenting cells facilitate direct and efficient expansion of tumor infiltrating lymphocytes

    PubMed Central

    2011-01-01

    Background Development of a standardized platform for the rapid expansion of tumor-infiltrating lymphocytes (TILs) with anti-tumor function from patients with limited TIL numbers or tumor tissues challenges their clinical application. Methods To facilitate adoptive immunotherapy, we applied genetically-engineered K562 cell-based artificial antigen presenting cells (aAPCs) for the direct and rapid expansion of TILs isolated from primary cancer specimens. Results TILs outgrown in IL-2 undergo rapid, CD28-independent expansion in response to aAPC stimulation that requires provision of exogenous IL-2 cytokine support. aAPCs induce numerical expansion of TILs that is statistically similar to an established rapid expansion method at a 100-fold lower feeder cell to TIL ratio, and greater than those achievable using anti-CD3/CD28 activation beads or extended IL-2 culture. aAPC-expanded TILs undergo numerical expansion of tumor antigen-specific cells, remain amenable to secondary aAPC-based expansion, and have low CD4/CD8 ratios and FOXP3+ CD4+ cell frequencies. TILs can also be expanded directly from fresh enzyme-digested tumor specimens when pulsed with aAPCs. These "young" TILs are tumor-reactive, positively skewed in CD8+ lymphocyte composition, CD28 and CD27 expression, and contain fewer FOXP3+ T cells compared to parallel IL-2 cultures. Conclusion Genetically-enhanced aAPCs represent a standardized, "off-the-shelf" platform for the direct ex vivo expansion of TILs of suitable number, phenotype and function for use in adoptive immunotherapy. PMID:21827675

  20. The establishment and expansion of an innovative centre for rational pharmacotherapy--determinants and challenges.

    PubMed

    Kardakis, Therese; Tomson, Göran; Wettermark, Björn; Brommels, Mats; Godman, Brian; Bastholm-Rahmner, Pia

    2015-01-01

    The regional Board of Health in Stockholm, Sweden, established the Pharmacotherapy Centre (PTC) to enhance the rational use of medicines. The PTC initiated computerised decision support systems and developed a range of electronic service products to sustain rational prescribing. However, knowledge about which determinants have supported or hindered the sustainability of this type of healthcare organisation is limited. This study aims to identify and explore determinants that support or challenge the development and sustainability of the PTC organisation, as well as investigate the key elements of their implementation efforts. An in-depth interview study among key informants involved in the establishment of the PTC organisation was conducted. Data were analysed using qualitative content analysis. Findings suggest that determinants enabling the development and expansion of this organisation include the presence of innovative characteristics among the PTC leadership and the ability of leaders to nurture visionary innovation in others, as well as the instigation of informal social networks and to identify end-user needs. Challenges included an ambiguous relationship to the pharmaceutical industry, an underestimation of the innovation-system fit and to undertake systematic evaluation of created impact by the organisation. Although prescriber use of electronic service products and adherence to an essential drug list increased over time, it remains difficult to identify methods required for demonstrating patient effects. Whereas some determinants enabled the successful expansion of the PTC organisation, others served to substantially hinder it. The determinants identified can pave the way for systematic investigations into organisational change and development research in the pharmaceutical field. Copyright © 2013 John Wiley & Sons, Ltd.

  1. 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.

  2. 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. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Moment expansion for ionospheric range error

    NASA Technical Reports Server (NTRS)

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

    1972-01-01

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

  4. Thermal Expansion of Ferromagnetic Superconductors:. Possible Application to UGe2

    NASA Astrophysics Data System (ADS)

    Hatayama, Nobukuni; Konno, Rikio

    2011-03-01

    We investigate the temperature dependence of thermal expansion of the ferromagnetic triplet superconductors and their thermal expansion coefficients below the superconducting transition temperature of a majority spin conduction band. The free energy of the ferromagnetic superconductors derived by Linder et al. is used. The superconducting gaps in the A2 phase of 3He and with a node in UGe2 are considered. By applying Takahashi's method to the free energy, i.e. by taking into account the volume dependence of the free energy explicitly, the temperature dependence of the thermal expansion and the thermal expansion coefficients is studied below the superconducting transition temperature of the majority spin conduction band. We find that we have anomalies of the thermal expansion in the vicinity of the superconducting transition temperatures and that we have divergence of the thermal expansion coefficients are divergent at the superconducting transition temperatures. The Grüneisen's relation between the temperature dependence of the thermal expansion coefficients and the temperature dependence of the specific heat at low temperatures is satisfied.

  5. Thermal Expansion of Ferromagnetic Superconductors:. Possible Application to UGe2

    NASA Astrophysics Data System (ADS)

    Hatayama, Nobukuni; Konno, Rikio

    We investigate the temperature dependence of thermal expansion of the ferromagnetic triplet superconductors and their thermal expansion coefficients below the superconducting transition temperature of a majority spin conduction band. The free energy of the ferromagnetic superconductors derived by Linder et al. is used. The superconducting gaps in the A2 phase of 3He and with a node in UGe2 are considered. By applying Takahashi's method to the free energy, i.e. by taking into account the volume dependence of the free energy explicitly, the temperature dependence of the thermal expansion and the thermal expansion coefficients is studied below the superconducting transition temperature of the majority spin conduction band. We find that we have anomalies of the thermal expansion in the vicinity of the superconducting transition temperatures and that we have divergence of the thermal expansion coefficients are divergent at the superconducting transition temperatures. The Grüneisen's relation between the temperature dependence of the thermal expansion coefficients and the temperature dependence of the specific heat at low temperatures is satisfied.

  6. Dimensionless number is central to stress relaxation and expansive growth of the cell wall.

    PubMed

    Ortega, Joseph K E

    2017-06-07

    Experiments demonstrate that both plastic and elastic deformation of the cell wall are necessary for wall stress relaxation and expansive growth of walled cells. A biophysical equation (Augmented Growth Equation) was previously shown to accurately model the experimentally observed wall stress relaxation and expansive growth rate. Here, dimensional analysis is used to obtain a dimensionless Augmented Growth Equation with dimensionless coefficients (groups of variables, or Π parameters). It is shown that a single Π parameter controls the wall stress relaxation rate. The Π parameter represents the ratio of plastic and elastic deformation rates, and provides an explicit relationship between expansive growth rate and the wall's mechanical properties. Values for Π are calculated for plant, algal, and fungal cells from previously reported experimental results. It is found that the Π values for each cell species are large and very different from each other. Expansive growth rates are calculated using the calculated Π values and are compared to those measured for plant and fungal cells during different growth conditions, after treatment with IAA, and in different developmental stages. The comparison shows good agreement and supports the claim that the Π parameter is central to expansive growth rate of walled cells.

  7. New Medicaid Enrollees See Health and Social Benefits in Pennsylvania’s Expansion

    PubMed Central

    Hom, Jeffrey K.; Wong, Charlene; Stillson, Christian; Zha, Jessica; Cannuscio, Carolyn C.; Cahill, Rachel; Grande, David

    2016-01-01

    Understanding how new Medicaid enrollees are approaching their own health and health care in the shifting health care landscape of the Affordable Care Act has implications for future outreach and enrollment efforts, as well as service planning for this population. The objective of this study was to explore the health care experiences and expectations of new Medicaid expansion beneficiaries in the immediate post-enrollment period. We conducted semistructured, qualitative interviews with a random sample of 40 adults in Philadelphia who had completed an application for Medicaid through a comprehensive benefits organization after January 1, 2015, when the Medicaid expansion in Pennsylvania took effect. We conducted an inductive, applied thematic analysis of interview transcripts. The new Medicaid beneficiaries described especially high levels of pent-up demand for care. Dental care was a far more pressing and motivating concern than medical care. Preventive services were also frequently mentioned. Participants anticipated that insurance would reduce both stress and financial strain and improve their experience in the health care system by raising their social standing. Participants highly valued the support of telephone application counselors in the Medicaid enrollment process to overcome bureaucratic obstacles they had encountered in the past. Dental care and preventive services appear to be high priorities for new Medicaid enrollees. Telephone outreach and enrollment support services can be an effective way to overcome past experiences with administrative barriers. PMID:27789732

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

    PubMed

    Ileri, Zehra; Basciftci, Faruk Ayhan

    2015-03-01

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

  9. Expansion-based passive ranging

    NASA Technical Reports Server (NTRS)

    Barniv, Yair

    1993-01-01

    A new technique of passive ranging which is based on utilizing the image-plane expansion experienced by every object as its distance from the sensor decreases is described. This technique belongs in the feature/object-based family. The motion and shape of a small window, assumed to be fully contained inside the boundaries of some object, is approximated by an affine transformation. The parameters of the transformation matrix are derived by initially comparing successive images, and progressively increasing the image time separation so as to achieve much larger triangulation baseline than currently possible. Depth is directly derived from the expansion part of the transformation. To a first approximation, image-plane expansion is independent of image-plane location with respect to the focus of expansion (FOE) and of platform maneuvers. Thus, an expansion-based method has the potential of providing a reliable range in the difficult image area around the FOE. In areas far from the FOE the shift parameters of the affine transformation can provide more accurate depth information than the expansion alone, and can thus be used similarly to the way they were used in conjunction with the Inertial Navigation Unit (INU) and Kalman filtering. However, the performance of a shift-based algorithm, when the shifts are derived from the affine transformation, would be much improved compared to current algorithms because the shifts - as well as the other parameters - can be obtained between widely separated images. Thus, the main advantage of this new approach is that, allowing the tracked window to expand and rotate, in addition to moving laterally, enables one to correlate images over a very long time span which, in turn, translates into a large spatial baseline - resulting in a proportionately higher depth accuracy.

  10. Expansion-based passive ranging

    NASA Technical Reports Server (NTRS)

    Barniv, Yair

    1993-01-01

    This paper describes a new technique of passive ranging which is based on utilizing the image-plane expansion experienced by every object as its distance from the sensor decreases. This technique belongs in the feature/object-based family. The motion and shape of a small window, assumed to be fully contained inside the boundaries of some object, is approximated by an affine transformation. The parameters of the transformation matrix are derived by initially comparing successive images, and progressively increasing the image time separation so as to achieve much larger triangulation baseline than currently possible. Depth is directly derived from the expansion part of the transformation. To a first approximation, image-plane expansion is independent of image-plane location with respect to the focus of expansion (FOE) and of platform maneuvers. Thus, an expansion-based method has the potential of providing a reliable range in the difficult image area around the FOE. In areas far from the FOE the shift parameters of the affine transformation can provide more accurate depth information than the expansion alone, and can thus be used similarly to the way they have been used in conjunction with the Inertial Navigation Unit (INU) and Kalman filtering. However, the performance of a shift-based algorithm, when the shifts are derived from the affine transformation, would be much improved compared to current algorithms because the shifts--as well as the other parameters--can be obtained between widely separated images. Thus, the main advantage of this new approach is that, allowing the tracked window to expand and rotate, in addition to moving laterally, enables one to correlate images over a very long time span which, in turn, translates into a large spatial baseline resulting in a proportionately higher depth accuracy.

  11. New Medicaid Enrollees See Health and Social Benefits in Pennsylvania's Expansion.

    PubMed

    Hom, Jeffrey K; Wong, Charlene; Stillson, Christian; Zha, Jessica; Cannuscio, Carolyn C; Cahill, Rachel; Grande, David

    2016-01-01

    Understanding how new Medicaid enrollees are approaching their own health and health care in the shifting health care landscape of the Affordable Care Act has implications for future outreach and enrollment efforts, as well as service planning for this population. The objective of this study was to explore the health care experiences and expectations of new Medicaid expansion beneficiaries in the immediate post-enrollment period. We conducted semistructured, qualitative interviews with a random sample of 40 adults in Philadelphia who had completed an application for Medicaid through a comprehensive benefits organization after January 1, 2015, when the Medicaid expansion in Pennsylvania took effect. We conducted an inductive, applied thematic analysis of interview transcripts. The new Medicaid beneficiaries described especially high levels of pent-up demand for care. Dental care was a far more pressing and motivating concern than medical care. Preventive services were also frequently mentioned. Participants anticipated that insurance would reduce both stress and financial strain and improve their experience in the health care system by raising their social standing. Participants highly valued the support of telephone application counselors in the Medicaid enrollment process to overcome bureaucratic obstacles they had encountered in the past. Dental care and preventive services appear to be high priorities for new Medicaid enrollees. Telephone outreach and enrollment support services can be an effective way to overcome past experiences with administrative barriers. © The Author(s) 2016.

  12. Evidence for a Humoral Mechanism in Volume Expansion Natriuresis

    PubMed Central

    Kaloyanides, George J.; Azer, Maher

    1971-01-01

    The role of a humoral mechanism in the natriuresis induced by volume expansion was evaluated using an isolated dog kidney perfused by a second dog which had been pretreated with desoxycorticosterone acetate (DOCA). Expansion of the perfusion dog with an equilibrated volume of blood from a reservoir, resulted in an increase in UnaV (sodium excretion) from 153.6±27.9 (sem) to 345.5±57.8 μEq/min, P<0.001. FEna (fractional sodium excretion) increased from 3.4±0.6 to 8.1±1.2%, P<0.01. The natriuresis occurred in the face of a significant decrease in Cin, RBF, and renal arterial pressure, and in the absence of any change in plasma protein concentration or packed cell volume. In a control group of experiments, sodium excretion did not change when the perfusion dog was not volume expanded, although Cin (inulin clearance) and RBF (renal blood flow) decreased to the same degree as in the expanded group. These data support the conclusion that volume expansion of the perfusion dog either stimulated the release of a natriuretic factor or suppressed the release of an antinatriuretic factor which was manifested by an increase in sodium excretion in the isolated kidney. PMID:5097568

  13. 18 CFR 154.309 - Incremental expansions.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Incremental expansions. 154.309 Section 154.309 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION... Changes § 154.309 Incremental expansions. (a) For every expansion for which incremental rates are charged...

  14. 18 CFR 154.309 - Incremental expansions.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 18 Conservation of Power and Water Resources 1 2014-04-01 2014-04-01 false Incremental expansions. 154.309 Section 154.309 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION... Changes § 154.309 Incremental expansions. (a) For every expansion for which incremental rates are charged...

  15. 18 CFR 154.309 - Incremental expansions.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 18 Conservation of Power and Water Resources 1 2011-04-01 2011-04-01 false Incremental expansions. 154.309 Section 154.309 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION... Changes § 154.309 Incremental expansions. (a) For every expansion for which incremental rates are charged...

  16. 18 CFR 154.309 - Incremental expansions.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 18 Conservation of Power and Water Resources 1 2013-04-01 2013-04-01 false Incremental expansions. 154.309 Section 154.309 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION... Changes § 154.309 Incremental expansions. (a) For every expansion for which incremental rates are charged...

  17. 18 CFR 154.309 - Incremental expansions.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 18 Conservation of Power and Water Resources 1 2012-04-01 2012-04-01 false Incremental expansions. 154.309 Section 154.309 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION... Changes § 154.309 Incremental expansions. (a) For every expansion for which incremental rates are charged...

  18. Protected areas facilitate species’ range expansions

    PubMed Central

    Thomas, Chris D.; Gillingham, Phillipa K.; Bradbury, Richard B.; Roy, David B.; Anderson, Barbara J.; Baxter, John M.; Bourn, Nigel A. D.; Crick, Humphrey Q. P.; Findon, Richard A.; Fox, Richard; Hodgson, Jenny A.; Holt, Alison R.; Morecroft, Mike D.; O’Hanlon, Nina J.; Oliver, Tom H.; Pearce-Higgins, James W.; Procter, Deborah A.; Thomas, Jeremy A.; Walker, Kevin J.; Walmsley, Clive A.; Wilson, Robert J.; Hill, Jane K.

    2012-01-01

    The benefits of protected areas (PAs) for biodiversity have been questioned in the context of climate change because PAs are static, whereas the distributions of species are dynamic. Current PAs may, however, continue to be important if they provide suitable locations for species to colonize at their leading-edge range boundaries, thereby enabling spread into new regions. Here, we present an empirical assessment of the role of PAs as targets for colonization during recent range expansions. Records from intensive surveys revealed that seven bird and butterfly species have colonized PAs 4.2 (median) times more frequently than expected from the availability of PAs in the landscapes colonized. Records of an additional 256 invertebrate species with less-intensive surveys supported these findings and showed that 98% of species are disproportionately associated with PAs in newly colonized parts of their ranges. Although colonizing species favor PAs in general, species vary greatly in their reliance on PAs, reflecting differences in the dependence of individual species on particular habitats and other conditions that are available only in PAs. These findings highlight the importance of current PAs for facilitating range expansions and show that a small subset of the landscape receives a high proportion of colonizations by range-expanding species. PMID:22893689

  19. Community Health Center Utilization Following the 2008 Medicaid Expansion in Oregon: Implications for the Affordable Care Act

    PubMed Central

    Bailey, Steffani R.; Cowburn, Stuart; Marino, Miguel; Angier, Heather; DeVoe, Jennifer E.

    2016-01-01

    Objectives. To assess longitudinal patterns of community health center (CHC) utilization and the effect of insurance discontinuity after Oregon’s 2008 Medicaid expansion (the Oregon Experiment). Methods. We conducted a retrospective cohort study with electronic health records and Medicaid data. We divided individuals who gained Medicaid in the Oregon Experiment into those who maintained (n = 788) or lost (n = 944) insurance coverage. We compared these groups with continuously insured (n = 921) and continuously uninsured (n = 5416) reference groups for community health center utilization rates over a 36-month period. Results. Both newly insured groups increased utilization in the first 6 months. After 6 months, use among those who maintained coverage stabilized at a level consistent with the continuously insured, whereas it returned to baseline for those who lost coverage. Conclusions. Individuals who maintained coverage through Oregon’s Medicaid expansion increased long-term utilization of CHCs, whereas those with unstable coverage did not. Policy implications. This study predicts long-term increase in CHC utilization following Affordable Care Act Medicaid expansion and emphasizes the need for policies that support insurance retention. PMID:26890164

  20. Rocket nozzle expansion ratio analysis for dual-fuel earth-to-orbit vehicles

    NASA Technical Reports Server (NTRS)

    Martin, James A.

    1989-01-01

    Results are reported from a recent study of the effects of Space Shuttle Main Engine expansion ratio modifications, in the cases of both single-stage and two-stage systems. Two-position nozzles were employed; after varying the lower expansion ratio while the higher was held constant at 120, the lower expansion ratio was held constant at 40 or 60 while the higher expansion ratio was varied. The expansion ratios for minimum vehicle dry mass are different for single-stage and two-stage systems. For two-stage systems, a single expansion ratio of 77.5 provides a lower dry mass than any two-position nozzle.

  1. Genetic traces of east-to-west human expansion waves in Eurasia.

    PubMed

    Chaix, Raphaëlle; Austerlitz, Frédéric; Hegay, Tatyana; Quintana-Murci, Lluís; Heyer, Evelyne

    2008-07-01

    In this study, we describe the landscape of human demographic expansions in Eurasia using a large continental Y chromosome and mitochondrial DNA dataset. Variation at these two uniparentally-inherited genetic systems retraces expansions that occurred in the past 60 ky, and shows a clear decrease of expansion ages from east to west Eurasia. To investigate the demographic events at the origin of this westward decrease of expansion ages, the estimated divergence ages between Eurasian populations are compared with the estimated expansion ages within each population. Both markers suggest that the demographic expansion diffused from east to west in Eurasia in a demic way, i.e., through migrations of individuals (and not just through diffusion of new technologies), highlighting the prominent role of eastern regions within Eurasia during Palaeolithic times. (c) 2008 Wiley-Liss, Inc.

  2. Principles of Thermal Expansion in Feldspars

    NASA Astrophysics Data System (ADS)

    Hovis, Guy; Medford, Aaron; Conlon, Maricate; Tether, Allison; Romanoski, Anthony

    2010-05-01

    Following the recent thermal expansion work of Hovis et al. (1) on AlSi3 feldspars, we have investigated the thermal expansion of plagioclase, Ba-K, and Ca-K feldspar crystalline solutions. X-ray powder diffraction data were collected between room temperature and 925 °C on six natural plagioclase specimens ranging in composition from anorthite to oligoclase, the K-exchanged equivalents of these plagioclase specimens, and five synthetic Ba-K feldspars with compositions ranging from 25 to 99 mol % BaAl2Si2O8. The resulting thermal expansion coefficients (α) for volume have been combined with earlier results for end-member Na- and K-feldspars (2,3). Unlike AlSi3 feldspars, Al2Si2 feldspars, including anorthite and celsian from the present study plus Sr- and Pb-feldspar from other workers (4,5), show essentially constant and very limited thermal expansion, regardless of divalent cation size. In the context of structures where the Lowenstein rule (6) requires Al and Si to alternate among tetrahedra, the proximity of bridging Al-O-Si oxygen ions to divalent neighbors (ranging from 0 to 2) produces short Ca-O (or Ba-O) bonds (7,8) that apparently are the result of local charge-balance requirements (9). Gibbs et al. (10) suggest that short bonds such as these have a partially covalent character. This in turn stiffens the structure. Thus, for feldspar series with coupled substitution the change away from a purely divalent M-site occupant gives the substituting (less strongly bonded) monovalent cations increasingly greater influence on thermal expansion. Overall, then, thermal expansion in the feldspar system is well represented on a plot of α against room-temperature volume, where one sees a quadrilateral bounded by data for (A) AlSi3 feldspars whose expansion behavior is controlled largely by the size of the monovalent alkali-site occupant, (B) Al2Si2 feldspars whose expansion is uniformly limited by partially-covalent bonds between divalent M-site occupants and

  3. Range expansion promotes cooperation in an experimental microbial metapopulation

    PubMed Central

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

    2013-01-01

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

  4. Pathogen-free, plasma-poor platelet lysate and expansion of human mesenchymal stem cells.

    PubMed

    Iudicone, Paola; Fioravanti, Daniela; Bonanno, Giuseppina; Miceli, Michelina; Lavorino, Claudio; Totta, Pierangela; Frati, Luigi; Nuti, Marianna; Pierelli, Luca

    2014-01-27

    Supplements to support clinical-grade cultures of mesenchymal stem cells (MSC) are required to promote growth and expansion of these cells. Platelet lysate (PL) is a human blood component which may replace animal serum in MSC cultures being rich in various growth factors. Here, we describe a plasma poor pathogen-free platelet lysate obtained by pooling 12 platelet (PLT) units, to produce a standardized and safe supplement for clinical-grade expansion of MSC. PL lots were obtained by combining 2 6-unit PLT pools in additive solution (AS) following a transfusional-based procedure including pathogen inactivation (PI) by Intercept technology and 3 cycles of freezing/thawing, followed by membrane removal. Three PI-PL and 3 control PL lots were produced to compare their ability to sustain bone marrow derived MSC selection and expansion. Moreover, two further PL, subjected to PI or not, were also produced starting from the same initial PLT pools to evaluate the impact of PI on growth factor concentration and capacity to sustain cell growth. Additional PI-PL lots were used for comparison with fetal bovine serum (FBS) on MSC expansion. Immunoregulatory properties of PI-PL-generated MSC were documented in vitro by mixed lymphocyte culture (MLC) and peripheral blood mononuclear cells (PBMC) mitogen induced proliferation. PI-PL and PL control lots had similar concentrations of 4 well-described growth factors endowed with MSC stimulating ability. Initial growth and MSC expansion by PI-PL and PL controls were comparable either using different MSC populations or in head to head experiments. Moreover, PI-PL and PL control sustained similar MSC growth of frozen/thawed MSC. Multilineage differentiation of PI-derived and PI-PL-derived MSC were maintained in any MSC cultures as well as their immunoregulatory properties. Finally, no direct impact of PI on growth factor concentration and MSC growth support was observed, whereas the capacity of FBS to sustain MSC expansion in basic

  5. Pathogen-free, plasma-poor platelet lysate and expansion of human mesenchymal stem cells

    PubMed Central

    2014-01-01

    Background Supplements to support clinical-grade cultures of mesenchymal stem cells (MSC) are required to promote growth and expansion of these cells. Platelet lysate (PL) is a human blood component which may replace animal serum in MSC cultures being rich in various growth factors. Here, we describe a plasma poor pathogen-free platelet lysate obtained by pooling 12 platelet (PLT) units, to produce a standardized and safe supplement for clinical-grade expansion of MSC. Methods PL lots were obtained by combining 2 6-unit PLT pools in additive solution (AS) following a transfusional-based procedure including pathogen inactivation (PI) by Intercept technology and 3 cycles of freezing/thawing, followed by membrane removal. Three PI-PL and 3 control PL lots were produced to compare their ability to sustain bone marrow derived MSC selection and expansion. Moreover, two further PL, subjected to PI or not, were also produced starting from the same initial PLT pools to evaluate the impact of PI on growth factor concentration and capacity to sustain cell growth. Additional PI-PL lots were used for comparison with fetal bovine serum (FBS) on MSC expansion. Immunoregulatory properties of PI-PL-generated MSC were documented in vitro by mixed lymphocyte culture (MLC) and peripheral blood mononuclear cells (PBMC) mitogen induced proliferation. Results PI-PL and PL control lots had similar concentrations of 4 well-described growth factors endowed with MSC stimulating ability. Initial growth and MSC expansion by PI-PL and PL controls were comparable either using different MSC populations or in head to head experiments. Moreover, PI-PL and PL control sustained similar MSC growth of frozen/thawed MSC. Multilineage differentiation of PI-derived and PI-PL-derived MSC were maintained in any MSC cultures as well as their immunoregulatory properties. Finally, no direct impact of PI on growth factor concentration and MSC growth support was observed, whereas the capacity of FBS to sustain

  6. Cycle expansions: From maps to turbulence

    NASA Astrophysics Data System (ADS)

    Lan, Y.

    2010-03-01

    We present a derivation, a physical explanation and applications of cycle expansions in different dynamical systems, ranging from simple one-dimensional maps to turbulence in fluids. Cycle expansion is a newly devised powerful tool for computing averages of physical observables in nonlinear chaotic systems which combines many innovative ideas developed in dynamical systems, such as hyperbolicity, invariant manifolds, symbolic dynamics, measure theory and thermodynamic formalism. The concept of cycle expansion has a deep root in theoretical physics, bearing a close analogy to cumulant expansion in statistical physics and effective action functional in quantum field theory, the essence of which is to represent a physical system in a hierarchical way by utilizing certain multiplicative structures such that the dominant parts of physical observables are captured by compact, maneuverable objects while minor detailed variations are described by objects with a larger space and time scale. The technique has been successfully applied to many low-dimensional dynamical systems and much effort has recently been made to extend its use to spatially extended systems. For one-dimensional systems such as the Kuramoto-Sivashinsky equation, the method turns out to be very effective while for more complex real-world systems including the Navier-Stokes equation, the method is only starting to yield its first fruits and much more work is needed to enable practical computations. However, the experience and knowledge accumulated so far is already very useful to a large set of research problems. Several such applications are briefly described in what follows. As more research effort is devoted to the study of complex dynamics of nonlinear systems, cycle expansion will undergo a fast development and find wide applications.

  7. Exponential expansion: galactic destiny or technological hubris?

    NASA Astrophysics Data System (ADS)

    Finney, B. R.

    Is it our destiny to expand exponentially to populate the galaxy, or is such a vision but an extreme example of technological hubris? The overall record of human evolution and dispersion over the Earth can be cited to support the view that we are a uniquely expansionary and technological animal bound for the stars, yet an examination of the fate of individual migrations and exploratory initiatives raises doubts. Although it may be in keeping with our hubristic nature to predict ultimate galactic expansion, there is no way to specify how far expansionary urges may drive our spacefaring descendants.

  8. Industrial trials of low-expansivity sawblades

    Treesearch

    Jeanne D. Danielson; Frank J. Worzala

    1992-01-01

    Low-expansivity alloys have the potential to reduce thermal instability of sawblades during the sawing operation. In preliminary industrial trials of sawblades made of low-expansivity alloy, sawing accuracy was improved 22 to 38 percent during normal sawing. When saws made of a low-expansivity alloy were operated with a large temperature gradient across the blade,...

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

    PubMed Central

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

    2017-01-01

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

  10. Mitochondrial phylogeography of moose (Alces alces): Late Pleistocene divergence and population expansion

    USGS Publications Warehouse

    Hundertmark, Kris J.; Shields, Gerald F.; Udina, Irina G.; Bowyer, R. Terry; Danilkin, Alexei A.; Schwartz, Charles C.

    2002-01-01

    We examined phylogeographic relationships of moose (Alces alces) worldwide to test the proposed existence of two geographic races and to infer the timing and extent of demographic processes underpinning the expansion of this species across the Northern Hemisphere in the late Pleistocene. Sequence variation within the left hypervariable domain of the control region occurred at low or moderate levels worldwide and was structured geographically. Partitioning of genetic variance among regions indicated that isolation by distance was the primary agent for differentiation of moose populations but does not support the existence of distinct eastern and western races. Levels of genetic variation and structure of phylogenetic trees identify Asia as the origin of all extant mitochondrial lineages. A recent coalescence is indicated, with the most recent common ancestor dating to the last ice age. Moose have undergone two episodes of population expansion, likely corresponding to the final interstade of the most recent ice age and the onset of the current interglacial. Timing of expansion for the population in the Yakutia–Manchuria region of eastern Asia indicates that it is one of the oldest populations of moose and may represent the source of founders of extant populations in North America, which were colonized within the last 15,000 years. Our data suggest an extended period of low population size or a severe bottleneck prior to the divergence and expansion of extant lineages and a recent, less-severe bottleneck among European lineages. Climate change during the last ice age, acting through contraction and expansion of moose habitat and the flooding of the Bering land bridge, undoubtedly was a key factor influencing the divergence and expansion of moose populations.

  11. Thermal expansion of L-ascorbic acid

    NASA Astrophysics Data System (ADS)

    Nicolaï, B.; Barrio, M.; Tamarit, J.-Ll.; Céolin, R.; Rietveld, I. B.

    2017-04-01

    The specific volume of vitamin C has been investigated by X-ray powder diffraction as a function of temperature from 110 K up to complete degradation around 440 K. Its thermal expansion is relatively small in comparison with other organic compounds with an expansivity α v of 1.2(3) × 10-4 K-1. The structure consists of strongly bound molecules in the ac plane through a dense network of hydrogen bonds. The thermal expansion is anisotropic. Along the b axis, the expansion has most leeway and is about 10 times larger than in the other directions.

  12. Compressive sampling of polynomial chaos expansions: Convergence analysis and sampling strategies

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

    Hampton, Jerrad; Doostan, Alireza, E-mail: alireza.doostan@colorado.edu

    2015-01-01

    Sampling orthogonal polynomial bases via Monte Carlo is of interest for uncertainty quantification of models with random inputs, using Polynomial Chaos (PC) expansions. It is known that bounding a probabilistic parameter, referred to as coherence, yields a bound on the number of samples necessary to identify coefficients in a sparse PC expansion via solution to an ℓ{sub 1}-minimization problem. Utilizing results for orthogonal polynomials, we bound the coherence parameter for polynomials of Hermite and Legendre type under their respective natural sampling distribution. In both polynomial bases we identify an importance sampling distribution which yields a bound with weaker dependence onmore » the order of the approximation. For more general orthonormal bases, we propose the coherence-optimal sampling: a Markov Chain Monte Carlo sampling, which directly uses the basis functions under consideration to achieve a statistical optimality among all sampling schemes with identical support. We demonstrate these different sampling strategies numerically in both high-order and high-dimensional, manufactured PC expansions. In addition, the quality of each sampling method is compared in the identification of solutions to two differential equations, one with a high-dimensional random input and the other with a high-order PC expansion. In both cases, the coherence-optimal sampling scheme leads to similar or considerably improved accuracy.« less

  13. 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. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Dynamic structure of confined shocks undergoing sudden expansion

    NASA Astrophysics Data System (ADS)

    Abate, G.; Shyy, W.

    2002-01-01

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

  15. Miniature cryogenic expansion turbines - A review

    NASA Astrophysics Data System (ADS)

    Sixsmith, H.

    Lord Rayleigh (1898) has first suggested the use of a turbine instead of a piston expander for the liquification of air. The development of expansion turbines is discussed, taking into account the first successful commercial application for cryogenic expansion turbines in Germany, Kapitza's turbine, work on much smaller turbines conducted in England, the development of a helium expansion turbine at the National Bureau of Standards, the development of small turboexpanders in Switzerland, the development of gas bearing expansion turbines, and the development of a small turboexpander similar to designs developed at the National Bureau of Standards. The reliability of cryogenic expansion turbines is discussed. It is found that applications for helium refrigerators and the demand for them would greatly increase if the reliability of these devices could be improved. Such a development would be crucial for the adoption of superconducting machinery by industry.

  16. 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.

  17. Inheritance patterns of ATCCT repeat interruptions in spinocerebellar ataxia type 10 (SCA10) expansions.

    PubMed

    Landrian, Ivette; McFarland, Karen N; Liu, Jilin; Mulligan, Connie J; Rasmussen, Astrid; Ashizawa, Tetsuo

    2017-01-01

    Spinocerebellar ataxia type 10 (SCA10), an autosomal dominant cerebellar ataxia disorder, is caused by a non-coding ATTCT microsatellite repeat expansion in the ataxin 10 gene. In a subset of SCA10 families, the 5'-end of the repeat expansion contains a complex sequence of penta- and heptanucleotide interruption motifs which is followed by a pure tract of tandem ATCCT repeats of unknown length at its 3'-end. Intriguingly, expansions that carry these interruption motifs correlate with an epileptic seizure phenotype and are unstable despite the theory that interruptions are expected to stabilize expanded repeats. To examine the apparent contradiction of unstable, interruption-positive SCA10 expansion alleles and to determine whether the instability originates outside of the interrupted region, we sequenced approximately 1 kb of the 5'-end of SCA10 expansions using the ATCCT-PCR product in individuals across multiple generations from four SCA10 families. We found that the greatest instability within this region occurred in paternal transmissions of the allele in stretches of pure ATTCT motifs while the intervening interrupted sequences were stable. Overall, the ATCCT interruption changes by only one to three repeat units and therefore cannot account for the instability across the length of the disease allele. We conclude that the AT-rich interruptions locally stabilize the SCA10 expansion at the 5'-end but do not completely abolish instability across the entire span of the expansion. In addition, analysis of the interruption alleles across these families support a parsimonious single origin of the mutation with a shared distant ancestor.

  18. Early study on the application of Nexcera ultra low thermal expansion ceramic to space telescopes

    NASA Astrophysics Data System (ADS)

    Kamiya, Tomohiro; Sugawara, Jun; Mizutani, Tadahito; Yasuda, Susumu; Kitamoto, Kazuya

    2017-09-01

    Optical mirrors for space telescopes, which require high precision and high thermal stability, have commonly been made of glass materials such as ultra low expansion glass (e.g. ULE®) or extremely low expansion glassceramic (e.g. ZERODUR® or CLEARCERAM®). These materials have been well-known for their reliability due to their long history of achievements in many space applications.

  19. Monitoring urban expansion and its effects on land use and land cover changes in Guangzhou city, China.

    PubMed

    Wu, Yanyan; Li, Shuyuan; Yu, Shixiao

    2016-01-01

    There are widespread concerns about urban sprawl in China. In response, modeling and assessing urban expansion and subsequent land use and land cover (LULC) changes have become important approaches to support decisions about appropriate development and land resource use. Guangzhou, a major metropolitan city in South China, has experienced rapid urbanization and great economic growth in the past few decades. This study applied a series of Landsat images to assess the urban expansion and subsequent LULC changes over 35 years, from 1979 to 2013. From start to end, urban expansion increased by 1512.24 km(2) with an annual growth rate of 11.25 %. There were four stages of urban growth: low rates from 1979 to 1990, increased rates from 1990 to 2001, high rates from 2001 to 2009, and steady increased rates from 2009 to 2013. There were also three different urban growth types in these different stages: edge-expansion growth, infilling growth, and spontaneous growth. Other land cover, such as cropland, forest, and mosaics of cropland and natural vegetation, were severely impacted as a result. To analyze these changes, we used landscape metrics to characterize the changes in the spatial patterns across the Guangzhou landscape and the impacts of urban growth on other types of land cover. The significant changes in LULC and urban expansion were highly correlated with economic development, population growth, technical progress, policy elements, and other similar indexes.

  20. 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

  1. Sheath and bulk expansion induced by RF bias in atmospheric pressure microwave plasma

    NASA Astrophysics Data System (ADS)

    Lee, Jimo; Nam, Woojin; Lee, Jae Koo; Yun, Gunsu

    2017-10-01

    A large axial volume expansion of microwave-driven plasma at atmospheric pressure is achieved by applying a low power radio frequency (RF) bias at an axial location well isolated from the original plasma bulk. The evolution of the plasma plume visualized by high speed ICCD imaging suggest that the free electrons drifting toward the bias electrode cause the prodigious expansion of the sheath, creating a stable plasma stream channel between the microwave and the RF electrodes. For argon plasma in ambient air, enhanced emissions of OH and N2 spectral lines are measured in the extended plume region, supporting the acceleration of electrons and subsequent generation of radical species. The coupling of RF bias with microwave provides an efficient way of enlarging the plasma volume and enhancing the production of radicals. Work supported by the National Research Foundation of Korea under BK21+ program and Grant No. 2015R1D1A1A01061556 (Ministry of Education).

  2. The Use of Electronic Mail To Support Off-Campus Student Learning.

    ERIC Educational Resources Information Center

    Doring, Allan

    A key element in the completion of study by off-campus students is support during their learning. The nature of off-campus study renders nearly impossible the face-to-face contact which provides expansion of lecture material, direct answers to problems, guidance on procedures, and immediate responses to learning difficulties. Electronic mail…

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

    NASA Astrophysics Data System (ADS)

    Yungster, Shaye; Trefny, Charles J.

    1992-04-01

    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.

  4. 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.

  5. An organ-specific role for ethylene in rose petal expansion during dehydration and rehydration

    PubMed Central

    Liu, Daofeng; Liu, Xiaojing; Meng, Yonglu; Sun, Cuihui; Tang, Hongshu; Jiang, Yudong; Khan, Muhammad Ali; Xue, Jingqi; Ma, Nan; Gao, Junping

    2013-01-01

    Dehydration is a major factor resulting in huge loss from cut flowers during transportation. In the present study, dehydration inhibited petal cell expansion and resulted in irregular flowers in cut roses, mimicking ethylene-treated flowers. Among the five floral organs, dehydration substantially elevated ethylene production in the sepals, whilst rehydration caused rapid and elevated ethylene levels in the gynoecia and sepals. Among the five ethylene biosynthetic enzyme genes (RhACS1–5), expression of RhACS1 and RhACS2 was induced by dehydration and rehydration in the two floral organs. Silencing both RhACS1 and RhACS2 significantly suppressed dehydration- and rehydration-induced ethylene in the sepals and gynoecia. This weakened the inhibitory effect of dehydration on petal cell expansion. β-glucuronidase activity driven by both the RhACS1 and RhACS2 promoters was dramatically induced in the sepals, pistil, and stamens, but not in the petals of transgenic Arabidopsis. This further supports the organ-specific induction of these two genes. Among the five rose ethylene receptor genes (RhETR1–5), expression of RhETR3 was predominantly induced by dehydration and rehydration in the petals. RhETR3 silencing clearly aggravated the inhibitory effect of dehydration on petal cell expansion. However, no significant difference in the effect between RhETR3-silenced flowers and RhETR-genes-silenced flowers was observed. Furthermore, RhETR-genes silencing extensively altered the expression of 21 cell expansion-related downstream genes in response to ethylene. These results suggest that induction of ethylene biosynthesis by dehydration proceeds in an organ-specific manner, indicating that ethylene can function as a mediator in dehydration-caused inhibition of cell expansion in rose petals. PMID:23599274

  6. 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.

  7. Multiple pathways of commodity crop expansion in tropical forest landscapes

    NASA Astrophysics Data System (ADS)

    Meyfroidt, Patrick; Carlson, Kimberly M.; Fagan, Matthew E.; Gutiérrez-Vélez, Victor H.; Macedo, Marcia N.; Curran, Lisa M.; DeFries, Ruth S.; Dyer, George A.; Gibbs, Holly K.; Lambin, Eric F.; Morton, Douglas C.; Robiglio, Valentina

    2014-07-01

    Commodity crop expansion, for both global and domestic urban markets, follows multiple land change pathways entailing direct and indirect deforestation, and results in various social and environmental impacts. Here we compare six published case studies of rapid commodity crop expansion within forested tropical regions. Across cases, between 1.7% and 89.5% of new commodity cropland was sourced from forestlands. Four main factors controlled pathways of commodity crop expansion: (i) the availability of suitable forestland, which is determined by forest area, agroecological or accessibility constraints, and land use policies, (ii) economic and technical characteristics of agricultural systems, (iii) differences in constraints and strategies between small-scale and large-scale actors, and (iv) variable costs and benefits of forest clearing. When remaining forests were unsuitable for agriculture and/or policies restricted forest encroachment, a larger share of commodity crop expansion occurred by conversion of existing agricultural lands, and land use displacement was smaller. Expansion strategies of large-scale actors emerge from context-specific balances between the search for suitable lands; transaction costs or conflicts associated with expanding into forests or other state-owned lands versus smallholder lands; net benefits of forest clearing; and greater access to infrastructure in already-cleared lands. We propose five hypotheses to be tested in further studies: (i) land availability mediates expansion pathways and the likelihood that land use is displaced to distant, rather than to local places; (ii) use of already-cleared lands is favored when commodity crops require access to infrastructure; (iii) in proportion to total agricultural expansion, large-scale actors generate more clearing of mature forests than smallholders; (iv) property rights and land tenure security influence the actors participating in commodity crop expansion, the form of land use displacement

  8. Molecular evidence for a recent demographic expansion in the puma (Puma concolor) (Mammalia, Felidae).

    PubMed

    Matte, Eunice M; Castilho, Camila S; Miotto, Renata A; Sana, Denis A; Johnson, Warren E; O'Brien, Stephen J; de Freitas, Thales R O; Eizirik, Eduardo

    2013-12-01

    The puma is an iconic predator that ranges throughout the Americas, occupying diverse habitats. Previous phylogeographic analyses have revealed that it exhibits moderate levels of genetic structure across its range, with few of the classically recognized subspecies being supported as distinct demographic units. Moreover, most of the species' molecular diversity was found to be in South America. To further investigate the phylogeographic structure and demographic history of pumas we analyzed mtDNA sequences from 186 individuals sampled throughout their range, with emphasis on South America. Our objectives were to refine the phylogeographic assessment within South America and to investigate the demographic history of pumas using a coalescent approach. Our results extend previous phylogeographic findings, reassessing the delimitation of historical population units in South America and demonstrating that this species experienced a considerable demographic expansion in the Holocene, ca. 8,000 years ago. Our analyses indicate that this expansion occurred in South America, prior to the hypothesized re-colonization of North America, which was therefore inferred to be even more recent. The estimated demographic history supports the interpretation that pumas suffered a severe demographic decline in the Late Pleistocene throughout their distribution, followed by population expansion and re-colonization of the range, initiating from South America.

  9. Molecular evidence for a recent demographic expansion in the puma (Puma concolor) (Mammalia, Felidae)

    PubMed Central

    Matte, Eunice M.; Castilho, Camila S.; Miotto, Renata A.; Sana, Denis A.; Johnson, Warren E.; O’Brien, Stephen J.; de Freitas, Thales R. O.; Eizirik, Eduardo

    2013-01-01

    The puma is an iconic predator that ranges throughout the Americas, occupying diverse habitats. Previous phylogeographic analyses have revealed that it exhibits moderate levels of genetic structure across its range, with few of the classically recognized subspecies being supported as distinct demographic units. Moreover, most of the species’ molecular diversity was found to be in South America. To further investigate the phylogeographic structure and demographic history of pumas we analyzed mtDNA sequences from 186 individuals sampled throughout their range, with emphasis on South America. Our objectives were to refine the phylogeographic assessment within South America and to investigate the demographic history of pumas using a coalescent approach. Our results extend previous phylogeographic findings, reassessing the delimitation of historical population units in South America and demonstrating that this species experienced a considerable demographic expansion in the Holocene, ca. 8,000 years ago. Our analyses indicate that this expansion occurred in South America, prior to the hypothesized re-colonization of North America, which was therefore inferred to be even more recent. The estimated demographic history supports the interpretation that pumas suffered a severe demographic decline in the Late Pleistocene throughout their distribution, followed by population expansion and re-colonization of the range, initiating from South America. PMID:24385863

  10. Multiple Inflammatory Cytokines Converge To Regulate CD8+ T Cell Expansion and Function during Tuberculosis.

    PubMed

    Booty, Matthew G; Nunes-Alves, Cláudio; Carpenter, Stephen M; Jayaraman, Pushpa; Behar, Samuel M

    2016-02-15

    The differentiation of effector CD8(+) T cells is a dynamically regulated process that varies during different infections and is influenced by the inflammatory milieu of the host. In this study, we define three signals regulating CD8(+) T cell responses during tuberculosis by focusing on cytokines known to affect disease outcome: IL-12, type I IFN, and IL-27. Using mixed bone marrow chimeras, we compared wild-type and cytokine receptor knockout CD8(+) T cells within the same mouse following aerosol infection with Mycobacterium tuberculosis. Four weeks postinfection, IL-12, type 1 IFN, and IL-27 were all required for efficient CD8(+) T cell expansion in the lungs. We next determined if these cytokines directly promote CD8(+) T cell priming or are required only for expansion in the lungs. Using retrogenic CD8(+) T cells specific for the M. tuberculosis Ag TB10.4 (EsxH), we observed that IL-12 is the dominant cytokine driving both CD8(+) T cell priming in the lymph node and expansion in the lungs; however, type I IFN and IL-27 have nonredundant roles supporting pulmonary CD8(+) T cell expansion. Thus, IL-12 is a major signal promoting priming in the lymph node, but a multitude of inflammatory signals converge in the lung to promote continued expansion. Furthermore, these cytokines regulate the differentiation and function of CD8(+) T cells during tuberculosis. These data demonstrate distinct and overlapping roles for each of the cytokines examined and underscore the complexity of CD8(+) T cell regulation during tuberculosis. Copyright © 2016 by The American Association of Immunologists, Inc.

  11. Moralistic gods, supernatural punishment and the expansion of human sociality.

    PubMed

    Purzycki, Benjamin Grant; Apicella, Coren; Atkinson, Quentin D; Cohen, Emma; McNamara, Rita Anne; Willard, Aiyana K; Xygalatas, Dimitris; Norenzayan, Ara; Henrich, Joseph

    2016-02-18

    Since the origins of agriculture, the scale of human cooperation and societal complexity has dramatically expanded. This fact challenges standard evolutionary explanations of prosociality because well-studied mechanisms of cooperation based on genetic relatedness, reciprocity and partner choice falter as people increasingly engage in fleeting transactions with genetically unrelated strangers in large anonymous groups. To explain this rapid expansion of prosociality, researchers have proposed several mechanisms. Here we focus on one key hypothesis: cognitive representations of gods as increasingly knowledgeable and punitive, and who sanction violators of interpersonal social norms, foster and sustain the expansion of cooperation, trust and fairness towards co-religionist strangers. We tested this hypothesis using extensive ethnographic interviews and two behavioural games designed to measure impartial rule-following among people (n = 591, observations = 35,400) from eight diverse communities from around the world: (1) inland Tanna, Vanuatu; (2) coastal Tanna, Vanuatu; (3) Yasawa, Fiji; (4) Lovu, Fiji; (5) Pesqueiro, Brazil; (6) Pointe aux Piments, Mauritius; (7) the Tyva Republic (Siberia), Russia; and (8) Hadzaland, Tanzania. Participants reported adherence to a wide array of world religious traditions including Christianity, Hinduism and Buddhism, as well as notably diverse local traditions, including animism and ancestor worship. Holding a range of relevant variables constant, the higher participants rated their moralistic gods as punitive and knowledgeable about human thoughts and actions, the more coins they allocated to geographically distant co-religionist strangers relative to both themselves and local co-religionists. Our results support the hypothesis that beliefs in moralistic, punitive and knowing gods increase impartial behaviour towards distant co-religionists, and therefore can contribute to the expansion of prosociality.

  12. 24 CFR 3280.608 - Hangers and supports.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Hangers and supports. (a) Strains and stresses. Piping in a plumbing system shall be installed without undue strains and stresses, and provision shall be made for expansion, contraction, and structural..., plastic drainage piping shall be supported at intervals not to exceed 4 feet and plastic water piping...

  13. 24 CFR 3280.608 - Hangers and supports.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Hangers and supports. (a) Strains and stresses. Piping in a plumbing system shall be installed without undue strains and stresses, and provision shall be made for expansion, contraction, and structural..., plastic drainage piping shall be supported at intervals not to exceed 4 feet and plastic water piping...

  14. Solid-density plasma expansion in intense ultra-short laser irradiation measured on nanometer scale and in real time

    NASA Astrophysics Data System (ADS)

    Kluge, T.; Metzkes, J.; Pelka, A.; Laso Garcia, A.; Prencipe, I.; Bussmann, M.; Zeil, K.; Schoenherr, T.; Hartley, N.; Gutt, C.; Galtier, E.; Nam, I.; Lee, Hj; McBride, Ee; Glenzer, S.; Huebner, U.; Roedel, C.; Nakatsutsumi, M.; Roedel, M.; Rehwald, M.; Garten, M.; Zacharias, M.; Schramm, U.; Cowan, T. E.

    2017-10-01

    Small Angle X-ray Scattering (SAXS) is discussed to allow unprecedented direct measurements limited only by the probe X-ray wavelength and duration. Here we present the first direct in-situ measurement of intense short-pulse laser - solid interaction that allows nanometer and high temporal resolution at the same time. A 120 fs laser pulse with energy 1 J was focused on a silicon membrane. The density was probed with an X-ray beam of 49 fs duration by SAXS. Despite prepulses, we can exclude premature bulk expansion. The plasma expansion is triggered only shortly before the main pulse, when an expansion of 10 nm within less than 200 fs was measured. Analysis of scattering patterns allows the first direct verification of numerical simulations. Supported by DOE FWP 100182, SF00515; EC FP7 LASERLAB-EUROPE/CHARPAC (contract 284464); German Federal Ministry of Education and Research (BMBF) under Contract Number 03Z1O511; MG and MZ supported by the European Union's Horizon 2020 No 654220.

  15. Series Expansion of Functions with He's Homotopy Perturbation Method

    ERIC Educational Resources Information Center

    Khattri, Sanjay Kumar

    2012-01-01

    Finding a series expansion, such as Taylor series, of functions is an important mathematical concept with many applications. Homotopy perturbation method (HPM) is a new, easy to use and effective tool for solving a variety of mathematical problems. In this study, we present how to apply HPM to obtain a series expansion of functions. Consequently,…

  16. Fine-scale genetic structure arises during range expansion of an invasive gecko.

    PubMed

    Short, Kristen Harfmann; Petren, Kenneth

    2011-01-01

    Processes of range expansion are increasingly important in light of current concerns about invasive species and range shifts due to climate change. Theoretical studies suggest that genetic structuring may occur during range expansion. Ephemeral genetic structure can have important evolutionary implications, such as propagating genetic changes along the wave front of expansion, yet few studies have shown evidence of such structure. We tested the hypothesis that genetic structure arises during range expansion in Hemidactylus mabouia, a nocturnal African gecko recently introduced to Florida, USA. Twelve highly variable microsatellite loci were used to screen 418 individuals collected from 43 locations from four sampling sites across Florida, representing a gradient from earlier (∼1990s) to very recent colonization. We found earlier colonized locations had little detectable genetic structure and higher allelic richness than more recently colonized locations. Genetic structuring was pronounced among locations at spatial scales of tens to hundreds of meters near the leading edge of range expansion. Despite the rapid pace of range expansion in this introduced gecko, dispersal is limited among many suitable habitat patches. Fine-scale genetic structure is likely the result of founder effects during colonization of suitable habitat patches. It may be obscured over time and by scale-dependent modes of dispersal. Further studies are needed to determine if such genetic structure affects adaptation and trait evolution in range expansions and range shifts.

  17. Performance of blend sign in predicting hematoma expansion in intracerebral hemorrhage: A meta-analysis.

    PubMed

    Yu, Zhiyuan; Zheng, Jun; Guo, Rui; Ma, Lu; Li, Mou; Wang, Xiaoze; Lin, Sen; Li, Hao; You, Chao

    2017-12-01

    Hematoma expansion is independently associated with poor outcome in intracerebral hemorrhage (ICH). Blend sign is a simple predictor for hematoma expansion on non-contrast computed tomography. However, its accuracy for predicting hematoma expansion is inconsistent in previous studies. This meta-analysis is aimed to systematically assess the performance of blend sign in predicting hematoma expansion in ICH. A systematic literature search was conducted. Original studies about predictive accuracy of blend sign for hematoma expansion in ICH were included. Pooled sensitivity, specificity, positive and negative likelihood ratios were calculated. Summary receiver operating characteristics curve was constructed. Publication bias was assessed by Deeks' funnel plot asymmetry test. A total of 5 studies with 2248 patients were included in this meta-analysis. The pooled sensitivity, specificity, positive and negative likelihood ratios of blend sign for predicting hematoma expansion were 0.28, 0.92, 3.4 and 0.78, respectively. The area under the curve (AUC) was 0.85. No significant publication bias was found. This meta-analysis demonstrates that blend sign is a useful predictor with high specificity for hematoma expansion in ICH. Further studies with larger sample size are still necessary to verify the accuracy of blend sign for predicting hematoma expansion. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Fully resolved simulations of expansion waves propagating into particle beds

    NASA Astrophysics Data System (ADS)

    Marjanovic, Goran; Hackl, Jason; Annamalai, Subramanian; Jackson, Thomas; Balachandar, S.

    2017-11-01

    There is a tremendous amount of research that has been done on compression waves and shock waves moving over particles but very little concerning expansion waves. Using 3-D direct numerical simulations, this study will explore expansion waves propagating into fully resolved particle beds of varying volume fractions and geometric arrangements. The objectives of these simulations are as follows: 1) To fully resolve all (1-way coupled) forces on the particles in a time varying flow and 2) to verify state-of-the-art drag models for such complex flows. We will explore a range of volume fractions, from very low ones that are similar to single particle flows, to higher ones where nozzling effects are observed between neighboring particles. Further, we will explore two geometric arrangements: body centered cubic and face centered cubic. We will quantify the effects that volume fraction and geometric arrangement plays on the drag forces and flow fields experienced by the particles. These results will then be compared to theoretical predictions from a model based on the generalized Faxen's theorem. This work was supported in part by the U.S. Department of Energy under the Predictive Science Academic Alliance Program, under Contract No. DE-NA0002378.

  19. 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.

  20. 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

  1. Activation tagging of Arabidopsis POLYGALACTURONASE INVOLVED IN EXPANSION2 promotes hypocotyl elongation, leaf expansion, stem lignification, mechanical stiffening, and lodging.

    PubMed

    Xiao, Chaowen; Barnes, William J; Zamil, M Shafayet; Yi, Hojae; Puri, Virendra M; Anderson, Charles T

    2017-03-01

    Pectin is the most abundant component of primary cell walls in eudicot plants. The modification and degradation of pectin affects multiple processes during plant development, including cell expansion, organ initiation, and cell separation. However, the extent to which pectin degradation by polygalacturonases affects stem development and secondary wall formation remains unclear. Using an activation tag screen, we identified a transgenic Arabidopsis thaliana line with longer etiolated hypocotyls, which overexpresses a gene encoding a polygalacturonase. We designated this gene as POLYGALACTURONASE INVOLVED IN EXPANSION2 (PGX2), and the corresponding activation tagged line as PGX2 AT . PGX2 is widely expressed in young seedlings and in roots, stems, leaves, flowers, and siliques of adult plants. PGX2-GFP localizes to the cell wall, and PGX2 AT plants show higher total polygalacturonase activity and smaller pectin molecular masses than wild-type controls, supporting a function for this protein in apoplastic pectin degradation. A heterologously expressed, truncated version of PGX2 also displays polygalacturonase activity in vitro. Like previously identified PGX1 AT plants, PGX2 AT plants have longer hypocotyls and larger rosette leaves, but they also uniquely display early flowering, earlier stem lignification, and lodging stems with enhanced mechanical stiffness that is possibly due to decreased stem thickness. Together, these results indicate that PGX2 both functions in cell expansion and influences secondary wall formation, providing a possible link between these two developmental processes. © 2016 The Authors The Plant Journal © 2016 John Wiley & Sons Ltd.

  2. Evaluation on expansive performance of the expansive soil using electrical responses

    NASA Astrophysics Data System (ADS)

    Chu, Ya; Liu, Songyu; Bate, Bate; Xu, Lei

    2018-01-01

    Light structures, such as highways and railroads, built on expansive soils are prone to damages from the swelling of their underlain soil layers. Considerable amount of research has been conducted to characterize the swelling properties of expansive soils. Current swell characterization models, however, are limited by lack of standardized tests. Electrical methods are non-destructive, and are faster and less expensive than the traditional geotechnical methods. Therefore, geo-electrical methods are attractive for defining soil characteristics, including the swelling behavior. In this study, comprehensive laboratory experiments were undertaken to measure the free swelling and electrical resistivity of the mixtures of commercial kaolinite and bentonite. The electrical conductivity of kaolinite-bentonite mixtures was measured by a self-developed four-electrode soil resistivity box. Increasing the free swelling rate of the kaolinite-bentonite mixtures (0.72 to 1 of porosity of soils samples) led to a reduction in the electrical resistivity and an increase in conductivity. A unique relationship between free swelling rate and normalized surface conductivity was constructed for expensive soils by eliminating influences of porosity and m exponent. Therefore, electrical response measurement can be used to characterize the free swelling rate of expensive soils.

  3. A cellular automata model for population expansion of Spartina alterniflora at Jiuduansha Shoals, Shanghai, China

    NASA Astrophysics Data System (ADS)

    Huang, Hua-mei; Zhang, Li-quan; Guan, Yu-juan; Wang, Dong-hui

    2008-03-01

    Biological invasion has received considerable attention recently because of increasing impacts on local ecosystems. Expansion of Spartina alterniflora, a non-native species, on the intertidal mudflats of Jiuduansha Shoals at the Yangtze River Estuary is a prime example of a spatially-structured invasion in a relatively simple habitat, for which strategic control efforts can be modeled and applied. Here, we developed a Cellular Automata (CA) model, in conjunction with Remote Sensing and Geographical Information Systems, to simulate the expanding process of S. alterniflora for a period of 8 years after being introduced to the new shoals, and to study the interactions between spatial pattern and ecosystem processes for the saltmarsh vegetation. The results showed that the CA model could simulate the population dynamics of S. alterniflora and Phragmites australis on the Jiuduansha Shoals successfully. The results strongly support the hypothesis of space pre-emption as well as range expansion with simple advancing wave fronts for these two species. In the Yangtze River Estuary, the native species P. australis shares the same niche with the exotic species S. alterniflora. However, the range expansion rate of P. australis was much slower than that of S. alterniflora. With the accretion of the Jiuduansha Shoals due to the large quantity of sediments deposited by the Yangtze River, a rapid range expansion of S. alterniflora is predicted to last for a long period into future. This study indicated the potential for this approach to provide valuable insights into population and community ecology of invasive species, which could be very important for wetland biodiversity conservation and resource management in the Yangtze River Estuary and other such impacted areas.

  4. Pressurized electrolysis stack with thermal expansion capability

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

    Bourgeois, Richard Scott

    The present techniques provide systems and methods for mounting an electrolyzer stack in an outer shell so as to allow for differential thermal expansion of the electrolyzer stack and shell. Generally, an electrolyzer stack may be formed from a material with a high coefficient of thermal expansion, while the shell may be formed from a material having a lower coefficient of thermal expansion. The differences between the coefficients of thermal expansion may lead to damage to the electrolyzer stack as the shell may restrain the thermal expansion of the electrolyzer stack. To allow for the differences in thermal expansion, themore » electrolyzer stack may be mounted within the shell leaving a space between the electrolyzer stack and shell. The space between the electrolyzer stack and the shell may be filled with a non-conductive fluid to further equalize pressure inside and outside of the electrolyzer stack.« less

  5. Node-Expansion Operators for the UCT Algorithm

    NASA Astrophysics Data System (ADS)

    Yajima, Takayuki; Hashimoto, Tsuyoshi; Matsui, Toshiki; Hashimoto, Junichi; Spoerer, Kristian

    Recent works on the MCTS and UCT framework in the domain of Go focused on introducing knowledge to the playout and on pruning variations from the tree, but so far node expansion has not been investigated. In this paper we show that delaying expansion according to the number of the siblings delivers a gain of more than 92% when compared to normal expansion. We propose three improvements; one that uses domain knowledge and two that are domain-independent methods. Experimental results show that all advanced operators significantly improve the UCT performance when compared to the basic delaying expansion. From the results we may conclude that the new expansion operators are an appropriate means to improve the UCT algorithm.

  6. Has Embase replaced MEDLINE since coverage expansion?

    PubMed

    Lam, Michael Thomas; De Longhi, Christina; Turnbull, Joseph; Lam, Helen Rose; Besa, Reena

    2018-04-01

    The research tested the authors' hypothesis that more researchers from the academic medicine community in the United States and Canada with institutional access to Embase had started using Embase to replace MEDLINE since Embase was expanded in 2010 to cover all MEDLINE records. We contacted libraries of 140 and 17 medical schools in the United States and Canada, respectively, to confirm their subscriptions to Embase 5 years before and 5 years after 2010. We searched the names of institutions with confirmed Embase access in Ovid MEDLINE and Embase to retrieve works authored by affiliates of those institutions. We then examined 100 randomly selected records from each of the 5 years before and 5 years after the Embase coverage expansion in 2010. We hypothesized that studies that used Embase but not MEDLINE would increase due to the Embase coverage expansion. The number of studies that used Embase but not MEDLINE did not change between the pre-2010 and post-2010 periods. Our hypothesis was refuted. Studies that used Embase but not MEDLINE did not increase post-2010. Our results suggest the academic medicine community in the United States and Canada that had access did not use Embase to replace MEDLINE, despite the Embase coverage expansion.

  7. Ocean Domains and Maximum Degree of Spherical Harmonic and Orthonormal Expansions

    NASA Technical Reports Server (NTRS)

    Rapp, R.

    1999-01-01

    Ocean domains used for the orthonormal (ON) systems are studied to determine the maximum degree of spherical harmonic and orthonormal expansions that can be constructed. Although it was shown that one domain was restricted to degree 24, others were shown could be constructed to determine expansions to at least degree 36. Since 1991 the maximum degree expansion used for several Ohio State studies has been 24. In this report it is shown that the maximum degree for the ocean domain used by Wang and Rapp [1994] was 32 and 29 for the domain used by Rapp, Zhang, Yi [1996]. A modification of the former domain was developed (D1e) that enabled a solution to degree 36 to be determined. A modification of the Rapp, Zhang, Yi domain (D7d) enabled a degree 30 solution to be made. Combination coefficients were developed for domain D1e, to degree 36, and to degree 30 for domain D7d. The degree 30 spherical harmonic expansion provided by Pavlis [1998] of the POCM_4B dynamic ocean topography (DOT), and the degree 30 part of the degree 360 expansion [Rapp. 1998] of the POCM_4B model was converted to an ON expansion valid for the D7d domain. The degree 36 part of the degree 360 expansion was converted to the ON expansion for the D1e domain. The square root of the degree variances of the various solutions were compared. The root mean square value of DOT from the Pai,lis expansion, after conversion to the ON system, was + or - 66.52 cm (D7d domain). The value from the degree 30 part of the 360 expansion was + or - 66.65 cm. The value based on the actual POCM-4B data, in the D7d domain, was + or - 66.74 cm showing excellent agreement with the ON results. If the spherical harmonic coefficients had been used the implied root mean square value was + or - 60.76 cm [Pavlis] and + or -59.70 cm [Rapp].

  8. Tunable thermal expansion and magnetism in Zr-doped ScF 3

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

    Wang, Tao; Xu, Jiale; Hu, Lei

    The negative thermal expansion (NTE) behavior provides us an opportunity to design materials with controllable coefficient of thermal expansion (CTE). In this letter, we report a tunable isotropic thermal expansion in the cubic (Sc1-xZrx)F3+δ over a wide temperature and CTE range (αl = -4.0 to +16.8 x 10-6 K-1, 298–648 K). The thermal expansion can be well adjusted from strong negative to zero, and finally to large positive. Intriguingly, isotropic zero thermal expansion (αl = 2.6 x 10-7 K-1, 298–648 K) has been observed in the composition of (Sc0.8Zr0.2)F3+δ. The controllable thermal expansion in (Sc1-xZrx)F3+δ is correlated to the localmore » structural distortion. Interestingly, the ordered magnetic behavior has been found in the zero thermal expansion compound of (Sc0.8Zr0.2)F3+δ at room temperature, which presumably correlates with the unpaired electron of the lower chemical valence of Zr cation. The present study provides a useful reference to control the thermal expansion and explore the multi-functionalization for NTE materials.« less

  9. Healthcare Utilization After a Children's Health Insurance Program Expansion in Oregon.

    PubMed

    Bailey, Steffani R; Marino, Miguel; Hoopes, Megan; Heintzman, John; Gold, Rachel; Angier, Heather; O'Malley, Jean P; DeVoe, Jennifer E

    2016-05-01

    The future of the Children's Health Insurance Program (CHIP) is uncertain after 2017. Survey-based research shows positive associations between CHIP expansions and children's healthcare utilization. To build on this prior work, we used electronic health record (EHR) data to assess temporal patterns of healthcare utilization after Oregon's 2009-2010 CHIP expansion. We hypothesized increased post-expansion utilization among children who gained public insurance. Using EHR data from 154 Oregon community health centers, we conducted a retrospective cohort study of pediatric patients (2-18 years old) who gained public insurance coverage during the Oregon expansion (n = 3054), compared to those who were continuously publicly insured (n = 10,946) or continuously uninsured (n = 10,307) during the 2-year study period. We compared pre-post rates of primary care visits, well-child visits, and dental visits within- and between-groups. We also conducted longitudinal analysis of monthly visit rates, comparing the three insurance groups. After Oregon's 2009-2010 CHIP expansions, newly insured patients' utilization rates were more than double their pre-expansion rates [adjusted rate ratios (95 % confidence intervals); increases ranged from 2.10 (1.94-2.26) for primary care visits to 2.77 (2.56-2.99) for dental visits]. Utilization among the newly insured spiked shortly after coverage began, then leveled off, but remained higher than the uninsured group. This study used EHR data to confirm that CHIP expansions are associated with increased utilization of essential pediatric primary and preventive care. These findings are timely to pending policy decisions that could impact children's access to public health insurance in the United States.

  10. Short interval expansion of Rényi entropy on torus

    NASA Astrophysics Data System (ADS)

    Chen, Bin; Wu, Jun-Bao; Zhang, Jia-ju

    2016-08-01

    We investigate the short interval expansion of the Rényi entropy for two-dimensional conformal field theory (CFT) on a torus. We require the length of the interval ℓ to be small with respect to the spatial and temporal sizes of the torus. The operator product expansion of the twist operators allows us to compute the short interval expansion of the Rényi entropy at any temperature. In particular, we pay special attention to the large c CFTs dual to the AdS3 gravity and its cousins. At both low and high temperature limits, we read the Rényi entropies to order ℓ6, and find good agreements with holographic results. Moreover, the expansion allows us to read 1 /c contribution, which is hard to get by expanding the thermal density matrix. We generalize the study to the case with the chemical potential as well.

  11. Medicaid enrollment after liver transplantation: Effects of medicaid expansion.

    PubMed

    Tumin, Dmitry; Hayes, Don; Washburn, W Kenneth; Tobias, Joseph D; Black, Sylvester M

    2016-08-01

    Liver transplantation (LT) recipients in the United States have low rates of paid employment, making some eligible for Medicaid public health insurance after transplant. We test whether recent expansions of Medicaid eligibility increased Medicaid enrollment and insurance coverage in this population. Patients of ages 18-59 years receiving first-time LTs in 2009-2013 were identified in the United Network for Organ Sharing registry and stratified according to insurance at transplantation (private versus Medicaid/Medicare). Posttransplant insurance status was assessed through June 2015. Difference-in-difference multivariate competing-risks models stratified on state of residence estimated effects of Medicaid expansion on Medicaid enrollment or use of uninsured care after LT. Of 12,837 patients meeting inclusion criteria, 6554 (51%) lived in a state that expanded Medicaid eligibility. Medicaid participation after LT was more common in Medicaid-expansion states (25%) compared to nonexpansion states (19%; P < 0.001). Multivariate analysis of 7279 patients with private insurance at transplantation demonstrated that after the effective date of Medicaid expansion (January 1, 2014), the hazard of posttransplant Medicaid enrollment increased in states participating in Medicaid expansion (hazard ratio [HR] = 1.5; 95% confidence interval [CI] = 1.1-2.0; P = 0.01), but not in states opting out of Medicaid expansion (HR = 0.8; 95% CI = 0.5-1.3; P = 0.37), controlling for individual characteristics and time-invariant state-level factors. No effects of Medicaid expansion on the use of posttransplant uninsured care were found, regardless of private or government insurance status at transplantation. Medicaid expansion increased posttransplant Medicaid enrollment among patients who had private insurance at transplantation, but it did not improve overall access to health insurance among LT recipients. Liver Transplantation 22 1075-1084 2016 AASLD. © 2016 American Association for the

  12. Preliminary Findings of the South Africa Power System Capacity Expansion and Operational Modelling Study: Preprint

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

    Reber, Timothy J; Chartan, Erol Kevin; Brinkman, Gregory L

    Wind and solar power contract prices have recently become cheaper than many conventional new-build alternatives in South Africa and trends suggest a continued increase in the share of variable renewable energy (vRE) on South Africa's power system with coal technology seeing the greatest reduction in capacity, see 'Figure 6: Percentage share by Installed Capacity (MW)' in [1]. Hence it is essential to perform a state-of-the-art grid integration study examining the effects of these high penetrations of vRE on South Africa's power system. Under the 21st Century Power Partnership (21CPP), funded by the U.S. Department of Energy, the National Renewable Energymore » Laboratory (NREL) has significantly augmented existing models of the South African power system to investigate future vRE scenarios. NREL, in collaboration with Eskom's Planning Department, further developed, tested and ran a combined capacity expansion and operational model of the South African power system including spatially disaggregated detail and geographical representation of system resources. New software to visualize and interpret modelling outputs has been developed, and scenario analysis of stepwise vRE build targets reveals new insight into associated planning and operational impacts and costs. The model, built using PLEXOS, is split into two components, firstly a capacity expansion model and secondly a unit commitment and economic dispatch model. The capacity expansion model optimizes new generation decisions to achieve the lowest cost, with a full understanding of capital cost and an approximated understanding of operational costs. The operational model has a greater set of detailed operational constraints and is run at daily resolutions. Both are run from 2017 through 2050. This investigation suggests that running both models in tandem may be the most effective means to plan the least cost South African power system as build plans seen to be more expensive than optimal by the capacity

  13. Separable Ernst-Shakin-Thaler expansions of local potentials

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

    Bund, G.W.

    The boundary condition Ernst-Shakin-Thaler method, introduced previously to generate separable expansions of local potentials of finite range, is applied to the study of the triplet s-wave Malfliet-Tjon potential. The effect of varying the radius where the boundary condition is applied on the T matrix is analyzed. Further, we compare the convergence of the n-d scattering cross sections in the quartet state below the breakup threshold for expansions corresponding to two different boundaries.

  14. Mesopores induced zero thermal expansion in single-crystal ferroelectrics.

    PubMed

    Ren, Zhaohui; Zhao, Ruoyu; Chen, Xing; Li, Ming; Li, Xiang; Tian, He; Zhang, Ze; Han, Gaorong

    2018-04-24

    For many decades, zero thermal expansion materials have been the focus of numerous investigations because of their intriguing physical properties and potential applications in high-precision instruments. Different strategies, such as composites, solid solution and doping, have been developed as promising approaches to obtain zero thermal expansion materials. However, microstructure controlled zero thermal expansion behavior via interface or surface has not been realized. Here we report the observation of an impressive zero thermal expansion (volumetric thermal expansion coefficient, -1.41 × 10 -6  K -1 , 293-623 K) in single-crystal ferroelectric PbTiO 3 fibers with large-scale faceted and enclosed mesopores. The zero thermal expansion behavior is attributed to a synergetic effect of positive thermal expansion near the mesopores due to the oxygen-based polarization screening and negative thermal expansion from an intrinsic ferroelectricity. Our results show that a fascinating surface construction in negative thermal expansion ferroelectric materials could be a promising strategy to realize zero thermal expansion.

  15. Regularized Chapman-Enskog expansion for scalar conservation laws

    NASA Technical Reports Server (NTRS)

    Schochet, Steven; Tadmor, Eitan

    1990-01-01

    Rosenau has recently proposed a regularized version of the Chapman-Enskog expansion of hydrodynamics. This regularized expansion resembles the usual Navier-Stokes viscosity terms at law wave-numbers, but unlike the latter, it has the advantage of being a bounded macroscopic approximation to the linearized collision operator. The behavior of Rosenau regularization of the Chapman-Enskog expansion (RCE) is studied in the context of scalar conservation laws. It is shown that thie RCE model retains the essential properties of the usual viscosity approximation, e.g., existence of traveling waves, monotonicity, upper-Lipschitz continuity..., and at the same time, it sharpens the standard viscous shock layers. It is proved that the regularized RCE approximation converges to the underlying inviscid entropy solution as its mean-free-path epsilon approaches 0, and the convergence rate is estimated.

  16. C9orf72 repeat expansions in rapid eye movement sleep behaviour disorder.

    PubMed

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

    2014-11-01

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

  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. Association Between the 2014 Medicaid Expansion and US Hospital Finances.

    PubMed

    Blavin, Fredric

    2016-10-11

    The Affordable Care Act expanded Medicaid eligibility for millions of low-income adults. The choice for states to expand Medicaid could affect the financial health of hospitals by decreasing the proportion of patient volume and unreimbursed expenses attributable to uninsured patients while increasing revenue from newly covered patients. To estimate the association between the Medicaid expansion in 2014 and hospital finances by assessing differences between hospitals in states that expanded Medicaid and in those states that did not expand Medicaid. Observational study with analysis of data for nonfederal general medical or surgical hospitals in fiscal years 2011 through 2014, using data from the American Hospital Association Annual Survey and the Health Care Cost Report Information System from the US Centers for Medicare & Medicaid Services. Multivariable difference-in-difference regression analyses were used to compare states with Medicaid expansion with states without Medicaid expansion. Hospitals in states that expanded Medicaid eligibility before January 2014 were excluded. Medicaid expansion in 2014, accounting for variation in fiscal year start dates. Hospital-reported information on uncompensated care, uncompensated care as a percentage of total hospital expenses, Medicaid revenue, Medicaid as a percentage of total revenue, operating margins, and excess margins. The sample included between 1200 and 1400 hospitals per fiscal year in 19 states with Medicaid expansion and between 2200 and 2400 hospitals per fiscal year in 25 states without Medicaid expansion (with sample size varying depending on the outcome measured). Expansion of Medicaid was associated with a decline of $2.8 million (95% CI, -$4.1 to -$1.6 million; P < .001) in mean annual uncompensated care costs per hospital. Hospitals in states with Medicaid expansion experienced a $3.2 million increase (95% CI, $0.9 to $5.6 million; P = .008) in mean annual Medicaid revenue per hospital, relative

  19. Social support in cyberspace: a content analysis of communication within a Huntington's disease online support group.

    PubMed

    Coulson, Neil S; Buchanan, Heather; Aubeeluck, Aimee

    2007-10-01

    Huntington's disease (HD) is an inherited disorder, characterized by a progressive degeneration of the brain. Due to the nature of the symptoms, the genetic element of the disease, and the fact that there is no cure, HD patients and those in their support network often experience considerable stress and anxiety. With an expansion in Internet access, individuals affected by HD have new opportunities for information retrieval and social support. The aim of this study is to examine the provision of social support in messages posted to a HD online support group bulletin board. In total, 1313 messages were content analyzed using a modified version of the social support behavior code developed by [Cutrona CE, Suhr J. Controllability of stressful events and satisfaction with spouse support behaviors. Commun Res 1992;19:154-74]. The analysis indicates that group members most frequently offered informational (56.2%) and emotional support (51.9%) followed by network support (48.4%) with esteem support (21.7%), and tangible assistance (9.8%) least frequently offered. This study suggests that exchanging informational and emotional support represents a key function of this online group. Online support groups provide a unique opportunity for health professionals to learn about the experiences and views of individuals affected by HD and explore where and why gaps may exist between evidence-based medicine and consumer behavior and expectations.

  20. 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.

  1. 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

  2. Negative thermal expansion near two structural quantum phase transitions

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

    Occhialini, Connor A.; Handunkanda, Sahan U.; Said, Ayman

    Recent experimental work has revealed that the unusually strong, isotropic structural negative thermal expansion in cubic perovskite ionic insulator ScF3 occurs in excited states above a ground state tuned very near a structural quantum phase transition, posing a question of fundamental interest as to whether this special circumstance is related to the anomalous behavior. To test this hypothesis, we report an elastic and inelastic x-ray scattering study of a second system Hg2I2 also tuned near a structural quantum phase transition while retaining stoichiometric composition and high crystallinity. We find similar behavior and significant negative thermal expansion below 100 K formore » dimensions along the body-centered-tetragonal c axis, bolstering the connection between negative thermal expansion and zero-temperature structural transitions.We identify the common traits between these systems and propose a set of materials design principles that can guide discovery of newmaterials exhibiting negative thermal expansion« less

  3. Negative thermal expansion near two structural quantum phase transitions

    NASA Astrophysics Data System (ADS)

    Occhialini, Connor A.; Handunkanda, Sahan U.; Said, Ayman; Trivedi, Sudhir; Guzmán-Verri, G. G.; Hancock, Jason N.

    2017-12-01

    Recent experimental work has revealed that the unusually strong, isotropic structural negative thermal expansion in cubic perovskite ionic insulator ScF3 occurs in excited states above a ground state tuned very near a structural quantum phase transition, posing a question of fundamental interest as to whether this special circumstance is related to the anomalous behavior. To test this hypothesis, we report an elastic and inelastic x-ray scattering study of a second system Hg2I2 also tuned near a structural quantum phase transition while retaining stoichiometric composition and high crystallinity. We find similar behavior and significant negative thermal expansion below 100 K for dimensions along the body-centered-tetragonal c axis, bolstering the connection between negative thermal expansion and zero-temperature structural transitions. We identify the common traits between these systems and propose a set of materials design principles that can guide discovery of new materials exhibiting negative thermal expansion.

  4. Measuring North Carolina pharmacists' support for expanded authority to administer human papillomavirus vaccines.

    PubMed

    Richman, Alice R; Swanson, Ryan S; Branham, Ashley R; Partridge, Brittney N

    2013-12-01

    To assess North Carolina pharmacists' level of support for expanded authority to administer human papillomavirus (HPV) vaccines to identify concerns/benefits about expanded authority and to understand what factors predict support for expanded authority. A 16-item electronic survey was e-mailed to all the pharmacists registered with the North Carolina Board of Pharmacy (n = 9502) between January and February 2011 (1600 pharmacists responded). The survey assessed HPV knowledge, level of support for expanded authority, and comfort level of HPV vaccine administration. Many (64%) pharmacists were supportive of a rule change/legislation that would authorize pharmacists to administer HPV vaccines. Younger pharmacists were more supportive of expansion when compared to older pharmacists (r = -.138, P < .001). Pharmacists with higher knowledge scores were more supportive of expansion (r = .223, P < .001). Reporting a higher level of comfort in administering HPV vaccines at their pharmacy was significantly and positively correlated with higher level of support for expansion (r = .624, P < .001). In the multivariate analysis, HPV knowledge, comfort level in administering vaccine, patient age, and type of pharmacy were all predictive of higher level of support for expanded authority where employed. A large proportion of pharmacists were supportive of an expanded role in providing HPV vaccines. Exploring alternate delivery mechanisms like this one is advantageous.

  5. Tunable thermal expansion in framework materials through redox intercalation

    NASA Astrophysics Data System (ADS)

    Chen, Jun; Gao, Qilong; Sanson, Andrea; Jiang, Xingxing; Huang, Qingzhen; Carnera, Alberto; Rodriguez, Clara Guglieri; Olivi, Luca; Wang, Lei; Hu, Lei; Lin, Kun; Ren, Yang; Lin, Zheshuai; Wang, Cong; Gu, Lin; Deng, Jinxia; Attfield, J. Paul; Xing, Xianran

    2017-02-01

    Thermal expansion properties of solids are of fundamental interest and control of thermal expansion is important for practical applications but can be difficult to achieve. Many framework-type materials show negative thermal expansion when internal cages are empty but positive thermal expansion when additional atoms or molecules fill internal voids present. Here we show that redox intercalation offers an effective method to control thermal expansion from positive to zero to negative by insertion of Li ions into the simple negative thermal expansion framework material ScF3, doped with 10% Fe to enable reduction. The small concentration of intercalated Li ions has a strong influence through steric hindrance of transverse fluoride ion vibrations, which directly controls the thermal expansion. Redox intercalation of guest ions is thus likely to be a general and effective method for controlling thermal expansion in the many known framework materials with phonon-driven negative thermal expansion.

  6. Model-independent cosmological constraints from growth and expansion

    NASA Astrophysics Data System (ADS)

    L'Huillier, Benjamin; Shafieloo, Arman; Kim, Hyungjin

    2018-05-01

    Reconstructing the expansion history of the Universe from Type Ia supernovae data, we fit the growth rate measurements and put model-independent constraints on some key cosmological parameters, namely, Ωm, γ, and σ8. The constraints are consistent with those from the concordance model within the framework of general relativity, but the current quality of the data is not sufficient to rule out modified gravity models. Adding the condition that dark energy density should be positive at all redshifts, independently of its equation of state, further constrains the parameters and interestingly supports the concordance model.

  7. A unified perturbation expansion for surface scattering

    NASA Technical Reports Server (NTRS)

    Rodriguez, Ernesto; Kim, Yunjin

    1992-01-01

    Starting with the extinction theorem, a perturbation expansion which, to first and second orders, converges over a wider domain than the small perturbation expansion and the momentum transfer expansion is presented. It is shown that, in the appropriate limits, both of these theories, as well as the two-scale expansion, are recovered. There is no adjustable parameter, such as a spectral split, in the theory. This theory is applied to random rough surfaces and derive analytic expressions for the coherent field and the bistatic cross section. Finally, a numerical test of the theory against method of moments results for Gaussian random rough surfaces with a power law spectrum is given. These results show that the expansion is ramarkably accurate over a large range of surface heights and slopes for both horizontal and vertical polarization.

  8. Assessing global range expansion in a cryptic species complex: insights from the red seaweed genus Asparagopsis (Florideophyceae).

    PubMed

    Zanolla, Marianela; Altamirano, María; Carmona, Raquel; De la Rosa, Julio; Souza-Egipsy, Virginia; Sherwood, Alison; Tsiamis, Konstantinos; Barbosa, Ana Márcia; Muñoz, Antonio Román; Andreakis, Nikos

    2018-02-01

    The mitochondrial genetic diversity, distribution and invasive potential of multiple cryptic operational taxonomic units (OTUs) of the red invasive seaweed Asparagopsis were assessed by studying introduced Mediterranean and Hawaiian populations. Invasive behavior of each Asparagopsis OTU was inferred from phylogeographic reconstructions, past historical demographic dynamics, recent range expansion assessments and future distributional predictions obtained from demographic models. Genealogical networks resolved Asparagopsis gametophytes and tetrasporophytes into four A. taxiformis and one A. armata cryptic OTUs. Falkenbergia isolates of A. taxiformis L3 were recovered for the first time in the western Mediterranean Sea and represent a new introduction for this area. Neutrality statistics supported past range expansion for A. taxiformis L1 and L2 in Hawaii. On the other hand, extreme geographic expansion and an increase in effective population size were found only for A. taxiformis L2 in the western Mediterranean Sea. Distribution models predicted shifts of the climatically suitable areas and population expansion for A. armata L1 and A. taxiformis L1 and L2. Our integrated study confirms a high invasive risk for A. taxiformis L1 and L2 in temperate and tropical areas. Despite the differences in predictions among modelling approaches, a number of regions were identified as zones with high invasion risk for A. taxiformis L2. Since range shifts are likely climate-driven phenomena, future invasive behavior cannot be excluded for the rest of the lineages. © 2017 Phycological Society of America.

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

    PubMed

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

    2001-03-01

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

  10. Evaluating expansion strategies for startup European Union dairy farm businesses.

    PubMed

    McDonald, R; Shalloo, L; Pierce, K M; Horan, B

    2013-06-01

    A stochastic whole-farm simulation model was used to examine alternative strategies for new entrant dairy farmers to grow and develop dairy farm businesses in the context of European Union (EU) milk quota abolition in 2015. Six alternative strategies were compared: remain static, natural growth expansion, waiting until after EU milk quota abolition to expand, a full-scale expansion strategy without milk quotas and not incurring super levy penalties, a full-scale expansion strategy with milk quotas and incurring super levy penalties, and once-a-day milking until EU milk quota abolition, followed by full-scale expansion. Each discrete whole farm investment strategy was evaluated over a 15-yr period (2013-2027) using multiple financial stability and risk indicators, including overall discounted farm business profitability, net worth change, return on investment, and financial risk. The results of this study indicate that, although associated with increased risk, dairy farm expansion will ensure the future profitability of the farm business. Within the context of EU milk quotas until 2015, the most attractive expansion strategy is to increase cow numbers while avoiding super levy fines using once-a-day milking techniques, increasing to the full capacity of the dairy farm once milk quotas are removed. In contrast, the results also indicate that dairy farms that remain static will experience a significant reduction in farm profitability in the coming year due to production cost inflation. Cash flow deficits were observed during the initial year of expansion and, therefore, rapidly expanding dairy farm businesses require a significant cash reserve to alleviate business risk during the initial year of expansion. The results of this analysis also indicate that dairy farm businesses that expand using lower cost capital investments and avoid milk quota super levy fines significantly reduce the financial risks associated with expansion. Copyright © 2013 American Dairy Science

  11. Self-expansion is associated with better adherence and obesity treatment outcomes in adults

    PubMed Central

    Xu, Xiaomeng; Leahey, Tricia M.; Boguszewski, Katherine; Krupel, Katie; Mailloux, Kimberly A.; Wing, Rena R.

    2016-01-01

    Background Previous studies have shown that self-expansion (e.g., increasing positive self-content via engaging in novel, rewarding activities) is associated with smoking cessation and attenuated cigarette cue-reactivity. Purpose This study examined whether self-expansion is associated with better adherence, weight loss, and physical activity (PA) outcomes within a weight loss intervention. Methods Participants from Shape Up Rhode Island 2012, a Web-based community wellness initiative, took part in a randomized controlled trial that involved a 12-week behavioral weight loss intervention (1). At baseline and post-intervention, objective weights and self-reported self-expansion and PA were obtained from 239 participants. Treatment adherence was assessed objectively. Results Self-expansion during treatment was significantly associated with percent weight loss including clinically significant weight loss (i.e. 5%), minutes of PA, and treatment adherence. These results held after controlling for relevant covariates. Conclusions This is the first study to show that self-expansion is associated with better behavioral weight loss outcomes including weight loss, adherence, and PA. These results suggest that self-expansion is a promising novel target for future research which could inform health interventions. PMID:27436226

  12. NATO’s Expansion Decision

    DTIC Science & Technology

    1997-04-01

    crime.…Meanwhile the US is making a 18 bad situation worse by insisting on the expansion of NATO, a project that has mobilized nationalist emotions in......xx-xx-1997 to xx-xx-1997 4. TITLE AND SUBTITLE NATO’s Expansion Decision Unclassified 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER

  13. Early Coverage, Access, Utilization, and Health Effects of the Affordable Care Act Medicaid Expansions: A Quasi-Experimental Study

    PubMed Central

    Wherry, Laura R.; Miller, Sarah

    2016-01-01

    Background In 2014, only 26 states and D.C. chose to implement the Affordable Care Act (ACA) Medicaid expansions for low-income adults. Objective To estimate whether the state Medicaid expansions were associated with changes in insurance coverage, access to and utilization of health care, and self-reported health. Design Comparison of outcomes before and after the expansions in states that did and did not expand Medicaid. Setting U.S. Participants Citizens aged 19–64 with family incomes below 138% of the Federal Poverty Level in the 2010–2014 National Health Interview Surveys. Measurements Health insurance coverage (private, Medicaid, uninsured); health insurance better than last year; visits with doctors in general practice and with specialists; hospitalizations and ED visits; skipped or delayed medical care; usual source of care; diagnoses of diabetes, high cholesterol, and hypertension; self-reported health; and depression. Results In the second half of 2014, low-income adults in expansion states experienced increased health insurance (7.4 percentage points; 95% CI, −11.3 to −3.4) and Medicaid (10.5 percentage points; 95% CI, 6.5 to 14.5) coverage, and increased quality of insurance coverage compared to a year ago (7.1 percentage points; 95% CI, 2.7 to 11.5) when compared to adults in states that did not expand Medicaid. Medicaid expansions were associated with increased visits with doctors in general practice (6.6 percentage points; 95% CI, 1.3 to 12.0), overnight hospital stays (2.4 percentage points; 95% CI, 0.7 to 4.2), and rates of diagnosis of diabetes (5.2 percentage points; 95% CI, 2.4 to 8.1) and high cholesterol (5.7 percentage points; 95% CI, 2.0 to 9.4); changes in other outcomes were not statistically significant. Limitations Observational study may be susceptible to unmeasured confounders; relies on self-reported data; limited post-ACA timeframe provides information on short-term changes only. Conclusions The ACA Medicaid expansions were

  14. Hormonal and electrolyte responses to acute isohemic volume expansion in unanesthetized rats

    NASA Technical Reports Server (NTRS)

    Chenault, V. M.; Morris, M.; Lynch, C. D.; Maultsby, S. J.; Hutchins, P. M.

    1993-01-01

    This study was undertaken to explore the time course of the metabolic response to isohemic blood volume expansion (30%) in normotensive, unanesthetized Sprague-Dawley rats. Whole blood, drawn from a femoral artery catheter of conscious donor rats, was infused into the jugular vein of recipient rats. Blood samples were drawn from a carotid artery of recipient rats at time points beginning immediately post-volume expansion (IPVE) up through 5 days post-volume expansion (PVE). To characterize the attendant compensatory mechanisms, the plasma concentrations of electrolytes and fluid regulatory hormones were determined. Hematocrit began to raise IPVE and was significantly elevated above control IPVE 20, 30, 40, 60, and 90 min, and 2, 4, 6, 8, 12, and 24 hr PVE. Consistent with our current understanding of the hormonal response to excess volume, atrial natriuretic factor was significantly increased above the prevolume expansion (control) values 0-30 min PVE. Surprisingly, plasma aldosterone levels were significantly increased above control at 20 and 30 min and 6 hr PVE, whereas plasma renin activity was significantly decreased 30-40 min PVE. Plasma sodium was not changed from control values except for a significant increase at 6 hr post-volume expansion. Plasma potassium, osmolality, and arginine vasopressin levels were not altered by the volume expansion. These studies delineate the physiologic time scheme operative in the regulation of fluid volume during acute ischemic volume expansion.

  15. Social class differences in self, attribution, and attention: socially expansive individualism of middle-class Americans.

    PubMed

    Bowman, Nicholas A; Kitayama, Shinobu; Nisbett, Richard E

    2009-07-01

    Although U.S. culture strongly sanctions the ideal of independence, the specific ways in which independence is realized may be variable depending, among other factors, on social class. Characterized by relative scarcity of social and material resources, working-class (WC) Americans were expected to strongly value self-reliance. In contrast, with choices among abundant resources, middle-class (MC) Americans were expected to value personal control and social expansiveness. In support of this analysis, relative to their WC counterparts, MC Americans reported more support from friends and greater likelihood of giving and receiving advice but less self-reliance (Study 1). Furthermore, we found evidence that this social difference has cognitive consequences: College students with MC backgrounds were more likely than their WC counterparts were to endorse situational attributions for others' behavior (Studies 2a and 2b) as well as to show holistic visual attention (Study 3).

  16. Effects of emergency department expansion on emergency department patient flow.

    PubMed

    Mumma, Bryn E; McCue, James Y; Li, Chin-Shang; Holmes, James F

    2014-05-01

    Emergency department (ED) crowding is an increasing problem associated with adverse patient outcomes. ED expansion is one method advocated to reduce ED crowding. The objective of this analysis was to determine the effect of ED expansion on measures of ED crowding. This was a retrospective study using administrative data from two 11-month periods before and after the expansion of an ED from 33 to 53 adult beds in an academic medical center. ED volume, staffing, and hospital admission and occupancy data were obtained either from the electronic health record (EHR) or from administrative records. The primary outcome was the rate of patients who left without being treated (LWBT), and the secondary outcome was total ED boarding time for admitted patients. A multivariable robust linear regression model was used to determine whether ED expansion was associated with the outcome measures. The mean (±SD) daily adult volume was 128 (±14) patients before expansion and 145 (±17) patients after. The percentage of patients who LWBT was unchanged: 9.0% before expansion versus 8.3% after expansion (difference = 0.6%, 95% confidence interval [CI] = -0.16% to 1.4%). Total ED boarding time increased from 160 to 180 hours/day (difference = 20 hours, 95% CI = 8 to 32 hours). After daily ED volume, low-acuity area volume, daily wait time, daily boarding hours, and nurse staffing were adjusted for, the percentage of patients who LWBT was not independently associated with ED expansion (p = 0.053). After ED admissions, ED intensive care unit (ICU) admissions, elective surgical admissions, hospital occupancy rate, ICU occupancy rate, and number of operational ICU beds were adjusted for, the increase in ED boarding hours was independently associated with the ED expansion (p = 0.005). An increase in ED bed capacity was associated with no significant change in the percentage of patients who LWBT, but had an unintended consequence of an increase in ED boarding hours. ED expansion alone does

  17. Phylogeography and demographic history of Lacerta lepida in the Iberian Peninsula: multiple refugia, range expansions and secondary contact zones

    PubMed Central

    2011-01-01

    Background The Iberian Peninsula is recognized as an important refugial area for species survival and diversification during the climatic cycles of the Quaternary. Recent phylogeographic studies have revealed Iberia as a complex of multiple refugia. However, most of these studies have focused either on species with narrow distributions within the region or species groups that, although widely distributed, generally have a genetic structure that relates to pre-Quaternary cladogenetic events. In this study we undertake a detailed phylogeographic analysis of the lizard species, Lacerta lepida, whose distribution encompasses the entire Iberian Peninsula. We attempt to identify refugial areas, recolonization routes, zones of secondary contact and date demographic events within this species. Results Results support the existence of 6 evolutionary lineages (phylogroups) with a strong association between genetic variation and geography, suggesting a history of allopatric divergence in different refugia. Diversification within phylogroups is concordant with the onset of the Pleistocene climatic oscillations. The southern regions of several phylogroups show a high incidence of ancestral alleles in contrast with high incidence of recently derived alleles in northern regions. All phylogroups show signs of recent demographic and spatial expansions. We have further identified several zones of secondary contact, with divergent mitochondrial haplotypes occurring in narrow zones of sympatry. Conclusions The concordant patterns of spatial and demographic expansions detected within phylogroups, together with the high incidence of ancestral haplotypes in southern regions of several phylogroups, suggests a pattern of contraction of populations into southern refugia during adverse climatic conditions from which subsequent northern expansions occurred. This study supports the emergent pattern of multiple refugia within Iberia but adds to it by identifying a pattern of refugia coincident

  18. Phylogeography and demographic history of Lacerta lepida in the Iberian Peninsula: multiple refugia, range expansions and secondary contact zones.

    PubMed

    Miraldo, Andreia; Hewitt, Godfrey M; Paulo, Octavio S; Emerson, Brent C

    2011-06-17

    The Iberian Peninsula is recognized as an important refugial area for species survival and diversification during the climatic cycles of the Quaternary. Recent phylogeographic studies have revealed Iberia as a complex of multiple refugia. However, most of these studies have focused either on species with narrow distributions within the region or species groups that, although widely distributed, generally have a genetic structure that relates to pre-Quaternary cladogenetic events. In this study we undertake a detailed phylogeographic analysis of the lizard species, Lacerta lepida, whose distribution encompasses the entire Iberian Peninsula. We attempt to identify refugial areas, recolonization routes, zones of secondary contact and date demographic events within this species. Results support the existence of 6 evolutionary lineages (phylogroups) with a strong association between genetic variation and geography, suggesting a history of allopatric divergence in different refugia. Diversification within phylogroups is concordant with the onset of the Pleistocene climatic oscillations. The southern regions of several phylogroups show a high incidence of ancestral alleles in contrast with high incidence of recently derived alleles in northern regions. All phylogroups show signs of recent demographic and spatial expansions. We have further identified several zones of secondary contact, with divergent mitochondrial haplotypes occurring in narrow zones of sympatry. The concordant patterns of spatial and demographic expansions detected within phylogroups, together with the high incidence of ancestral haplotypes in southern regions of several phylogroups, suggests a pattern of contraction of populations into southern refugia during adverse climatic conditions from which subsequent northern expansions occurred. This study supports the emergent pattern of multiple refugia within Iberia but adds to it by identifying a pattern of refugia coincident with the southern distribution

  19. 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

  20. Tunable thermal expansion in framework materials through redox intercalation

    PubMed Central

    Chen, Jun; Gao, Qilong; Sanson, Andrea; Jiang, Xingxing; Huang, Qingzhen; Carnera, Alberto; Rodriguez, Clara Guglieri; Olivi, Luca; Wang, Lei; Hu, Lei; Lin, Kun; Ren, Yang; Lin, Zheshuai; Wang, Cong; Gu, Lin; Deng, Jinxia; Attfield, J. Paul; Xing, Xianran

    2017-01-01

    Thermal expansion properties of solids are of fundamental interest and control of thermal expansion is important for practical applications but can be difficult to achieve. Many framework-type materials show negative thermal expansion when internal cages are empty but positive thermal expansion when additional atoms or molecules fill internal voids present. Here we show that redox intercalation offers an effective method to control thermal expansion from positive to zero to negative by insertion of Li ions into the simple negative thermal expansion framework material ScF3, doped with 10% Fe to enable reduction. The small concentration of intercalated Li ions has a strong influence through steric hindrance of transverse fluoride ion vibrations, which directly controls the thermal expansion. Redox intercalation of guest ions is thus likely to be a general and effective method for controlling thermal expansion in the many known framework materials with phonon-driven negative thermal expansion. PMID:28181576

  1. Tunable thermal expansion in framework materials through redox intercalation

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

    Chen, Jun; Gao, Qilong; Sanson, Andrea

    Thermal expansion properties of solids are of fundamental interest and control of thermal expansion is important for practical applications but can be difficult to achieve. Many framework type materials show negative thermal expansion when internal cages are empty but positive thermal expansion when additional atoms or molecules fill internal voids present, offering a potential route for control. Here we show that redox intercalation offers an effective method to control thermal expansion from positive to zero to negative by insertion of Li ions into the simple negative thermal expansion framework material ScF 3, doped with 10% Fe to enable reduction. Themore » small concentration of intercalated Li ions has a strong influence through steric hindrance of transverse fluoride ion vibrations, which directly controls the thermal expansion. As a result, redox intercalation of guest ions is thus likely to be a general and effective method for controlling thermal expansion in the many known framework materials with phonon-driven negative thermal expansion.« less

  2. Tunable thermal expansion in framework materials through redox intercalation

    DOE PAGES

    Chen, Jun; Gao, Qilong; Sanson, Andrea; ...

    2017-02-09

    Thermal expansion properties of solids are of fundamental interest and control of thermal expansion is important for practical applications but can be difficult to achieve. Many framework type materials show negative thermal expansion when internal cages are empty but positive thermal expansion when additional atoms or molecules fill internal voids present, offering a potential route for control. Here we show that redox intercalation offers an effective method to control thermal expansion from positive to zero to negative by insertion of Li ions into the simple negative thermal expansion framework material ScF 3, doped with 10% Fe to enable reduction. Themore » small concentration of intercalated Li ions has a strong influence through steric hindrance of transverse fluoride ion vibrations, which directly controls the thermal expansion. As a result, redox intercalation of guest ions is thus likely to be a general and effective method for controlling thermal expansion in the many known framework materials with phonon-driven negative thermal expansion.« less

  3. Gradient composite metal-ceramic foam as supportive component for planar SOFCs and MIEC membranes

    NASA Astrophysics Data System (ADS)

    Smorygo, Oleg; Mikutski, Vitali; Marukovich, Alexander; Sadykov, Vladislav; Usoltsev, Vladimir; Mezentseva, Natalia; Borodinecs, Anatolijs; Bobrenok, Oleg

    2011-06-01

    A novel approach to the design of planar gradient porous supports for the thin-film SOFCs and MIEC membranes is described. The support's thermal expansion is controlled by the creation of a two-component composite metal-ceramic foam structure. Thin MIEC membranes and SOFCs were prepared on the composite supports by the layerwise deposition of composite functional layers including complex fluorites and perovskites. Lab-scale studies demonstrated promising performance of both MIEC membrane and SOFC.

  4. An Analytical Diffusion–Expansion Model for Forbush Decreases Caused by Flux Ropes

    NASA Astrophysics Data System (ADS)

    Dumbović, Mateja; Heber, Bernd; Vršnak, Bojan; Temmer, Manuela; Kirin, Anamarija

    2018-06-01

    We present an analytical diffusion–expansion Forbush decrease (FD) model ForbMod, which is based on the widely used approach of an initially empty, closed magnetic structure (i.e., flux rope) that fills up slowly with particles by perpendicular diffusion. The model is restricted to explaining only the depression caused by the magnetic structure of the interplanetary coronal mass ejection (ICME). We use remote CME observations and a 3D reconstruction method (the graduated cylindrical shell method) to constrain initial boundary conditions of the FD model and take into account CME evolutionary properties by incorporating flux rope expansion. Several flux rope expansion modes are considered, which can lead to different FD characteristics. In general, the model is qualitatively in agreement with observations, whereas quantitative agreement depends on the diffusion coefficient and the expansion properties (interplay of the diffusion and expansion). A case study was performed to explain the FD observed on 2014 May 30. The observed FD was fitted quite well by ForbMod for all expansion modes using only the diffusion coefficient as a free parameter, where the diffusion parameter was found to correspond to an expected range of values. Our study shows that, in general, the model is able to explain the global properties of an FD caused by a flux rope and can thus be used to help understand the underlying physics in case studies.

  5. Calculation of thermal expansion coefficient of glasses based on topological constraint theory

    NASA Astrophysics Data System (ADS)

    Zeng, Huidan; Ye, Feng; Li, Xiang; Wang, Ling; Yang, Bin; Chen, Jianding; Zhang, Xianghua; Sun, Luyi

    2016-10-01

    In this work, the thermal expansion behavior and the structure configuration evolution of glasses were studied. Degree of freedom based on the topological constraint theory is correlated with configuration evolution; considering the chemical composition and the configuration change, the analytical equation for calculating the thermal expansion coefficient of glasses from degree of freedom was derived. The thermal expansion of typical silicate and chalcogenide glasses was examined by calculating their thermal expansion coefficients (TEC) using the approach stated above. The results showed that this approach was energetically favorable for glass materials and revealed the corresponding underlying essence from viewpoint of configuration entropy. This work establishes a configuration-based methodology to calculate the thermal expansion coefficient of glasses that, lack periodic order.

  6. Expansion tunnel performance with and without an electromagnetically opened tertiary diaphragm

    NASA Technical Reports Server (NTRS)

    Miller, C. G.

    1977-01-01

    A study was conducted to examine the effect of synchronization of an electromagnetically opened tertiary diaphragm with flow arrival at the diaphragm on the pitot pressure measured at the test section of an expansion tunnel. The effect of tertiary diaphragm pressure ratio (ratio of initial nozzle pressure to quiescent acceleration section pressure) on the pitot pressure time history is also determined. The inadequacy of a pressure transducer protection arrangement used in previous expansion tube and expansion tunnel tests was revealed.

  7. Chemical recombination in an expansion tube

    NASA Technical Reports Server (NTRS)

    Bakos, Robert J.; Morgan, Richard G.

    1994-01-01

    The note describes the theoretical basis of chemical recombination in an expansion tube which simulates energy, Reynolds number, and stream chemistry at near-orbital velocities. Expansion tubes can satisfy ground-based hypersonic propulsion and aerothermal testing requirements.

  8. Hole expansion test of third generation steels

    NASA Astrophysics Data System (ADS)

    Agirre, Julen; Mendiguren, Joseba; Galdos, Lander; de Argandoña, Eneko Sáenz

    2017-10-01

    The trend towards the implementation of new materials in the chassis of the automobiles is considerably making more complex the manufacturing of the components that built it up. In this scenario materials with higher strengths and lower formabilities are daily faced by tool makers and component producers what reduces the process windows and makes the forming processes to be in the limits of the materials. One of the concerns that tool makers must face during the definition of the tools is the expansion ratios that the holes in the sheet may reach before producing a breakage due to the stretching of the material (also known as edge cracks). For the characterization of such limits, a standard test, the hole expansion test, can be applied so that the limits of the material are known. At the present study, hole expansion tests of a third generation steel, Fortiform1050 with a thickness of 1.2 millimeters have been carried out and compared them to a mild steel, DX54D with a thickness of 0.6 millimeters. A comparison for each material in terms of technology used to punch the hole, mechanical punching vs laser cutting has also been conducted. In addition, the measurement technique (online measurement vs offline measurement) followed in the Hole Expansion Ratio (HER) identification has also been analyzed. Finally, differences between both materials and techniques are presented.

  9. Demographic expansion of two Tamarix species along the Yellow River caused by geological events and climate change in the Pleistocene.

    PubMed

    Liang, Hong-Yan; Feng, Zhi-Pei; Pei, Bing; Li, Yong; Yang, Xi-Tian

    2018-01-08

    The geological events and climatic fluctuations during the Pleistocene played important roles in shaping patterns of species distribution. However, few studies have evaluated the patterns of species distribution that were influenced by the Yellow River. The present work analyzed the demography of two endemic tree species that are widely distributed along the Yellow River, Tamarix austromongolica and Tamarix chinensis, to understand the role of the Yellow River and Pleistocene climate in shaping their distribution patterns. The most common chlorotype, chlorotype 1, was found in all populations, and its divergence time could be dated back to 0.19 million years ago (Ma). This dating coincides well with the formation of the modern Yellow River and the timing of Marine Isotope Stages 5e-6 (MIS 5e-6). Bayesian reconstructions along with models of paleodistribution revealed that these two species experienced a demographic expansion in population size during the Quaternary period. Approximate Bayesian computation analyses supported a scenario of expansion approximately from the upper to lower reaches of the Yellow River. Our results provide support for the roles of the Yellow River and the Pleistocene climate in driving demographic expansion of the populations of T. austromongolica and T. chinensis. These findings are useful for understanding the effects of geological events and past climatic fluctuations on species distribution patterns.

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

    DOT National Transportation Integrated Search

    2014-12-01

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

  11. Engineering Technical Support Center Annual Report Fiscal Year 2014; Technical Support and Innovative Research for Contaminated Sites

    EPA Science Inventory

    This report highlights significant projects that the ETSC has supported throughout fiscal year 2014. Projects have addressed an array of environmental scenarios, including but not limited to remote mining contamination, expansive landfill waste, sediment remediation by capping, ...

  12. Changes in Emergency Department Utilization After Early Medicaid Expansion in California.

    PubMed

    Sabik, Lindsay M; Cunningham, Peter J; Tehrani, Ali Bonakdar

    2017-06-01

    Medicaid expansions aim to improve access to primary care, which could reduce nonemergent (NE) use of the emergency department (ED). In contrast, Medicaid enrollees use the ED more than other groups, including the uninsured. Thus, the expected impact of Medicaid expansion on ED use is unclear. To estimate changes in total and NE ED visits as a result of California's early Medicaid expansion under the Affordable Care Act. In addition to overall changes in the number of visits, changes by payer and safety net hospital status are examined. We used a quasi-experimental approach to examine changes in ED utilization, comparing California expansion counties to comparison counties from California and 2 other states in the same region that did not implement Medicaid expansion during the study period. Regression estimates show no significant change in total number of ED visits following expansion. Medicaid visits increased by 145 visits per hospital-quarter in the first year following expansion and 242 visits subsequent to the first year, whereas visits among uninsured patients decreased by 129 visits per hospital-quarter in the first year and 175 visits in subsequent years, driven by changes at safety net hospitals. We also observe an increase in NE visits per hospital-quarter paid for by Medicaid, and a significant decrease in uninsured NE visits. Medicaid expansions in California were associated with increases in ED visits paid for by Medicaid and declines in uninsured visits. Expansion was also associated with changes in NE visits among Medicaid enrollees and the uninsured.

  13. C9ORF72 repeat expansion in Australian and Spanish frontotemporal dementia patients.

    PubMed

    Dobson-Stone, Carol; Hallupp, Marianne; Loy, Clement T; Thompson, Elizabeth M; Haan, Eric; Sue, Carolyn M; Panegyres, Peter K; Razquin, Cristina; Seijo-Martínez, Manuel; Rene, Ramon; Gascon, Jordi; Campdelacreu, Jaume; Schmoll, Birgit; Volk, Alexander E; Brooks, William S; Schofield, Peter R; Pastor, Pau; Kwok, John B J

    2013-01-01

    A hexanucleotide repeat expansion in C9ORF72 has been established as a common cause of frontotemporal dementia (FTD). However, the minimum repeat number necessary for disease pathogenesis is not known. The aims of our study were to determine the frequency of the C9ORF72 repeat expansion in two FTD patient collections (one Australian and one Spanish, combined n = 190), to examine C9ORF72 expansion allele length in a subset of FTD patients, and to examine C9ORF72 allele length in 'non-expansion' patients (those with <30 repeats). The C9ORF72 repeat expansion was detected in 5-17% of patients (21-41% of familial FTD patients). For one family, the expansion was present in the proband but absent in the mother, who was diagnosed with dementia at age 68. No association was found between C9ORF72 non-expanded allele length and age of onset and in the Spanish sample mean allele length was shorter in cases than in controls. Southern blotting analysis revealed that one of the nine 'expansion-positive' patients examined, who had neuropathologically confirmed frontotemporal lobar degeneration with TDP-43 pathology, harboured an 'intermediate' allele with a mean size of only ∼65 repeats. Our study indicates that the C9ORF72 repeat expansion accounts for a significant proportion of Australian and Spanish FTD cases. However, C9ORF72 allele length does not influence the age at onset of 'non-expansion' FTD patients in the series examined. Expansion of the C9ORF72 allele to as little as ∼65 repeats may be sufficient to cause disease.

  14. A cluster expansion model for predicting activation barrier of atomic processes

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

    Rehman, Tafizur; Jaipal, M.; Chatterjee, Abhijit, E-mail: achatter@iitk.ac.in

    2013-06-15

    We introduce a procedure based on cluster expansion models for predicting the activation barrier of atomic processes encountered while studying the dynamics of a material system using the kinetic Monte Carlo (KMC) method. Starting with an interatomic potential description, a mathematical derivation is presented to show that the local environment dependence of the activation barrier can be captured using cluster interaction models. Next, we develop a systematic procedure for training the cluster interaction model on-the-fly, which involves: (i) obtaining activation barriers for handful local environments using nudged elastic band (NEB) calculations, (ii) identifying the local environment by analyzing the NEBmore » results, and (iii) estimating the cluster interaction model parameters from the activation barrier data. Once a cluster expansion model has been trained, it is used to predict activation barriers without requiring any additional NEB calculations. Numerical studies are performed to validate the cluster expansion model by studying hop processes in Ag/Ag(100). We show that the use of cluster expansion model with KMC enables efficient generation of an accurate process rate catalog.« less

  15. Filtering with Marked Point Process Observations via Poisson Chaos Expansion

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

    Sun Wei, E-mail: wsun@mathstat.concordia.ca; Zeng Yong, E-mail: zengy@umkc.edu; Zhang Shu, E-mail: zhangshuisme@hotmail.com

    2013-06-15

    We study a general filtering problem with marked point process observations. The motivation comes from modeling financial ultra-high frequency data. First, we rigorously derive the unnormalized filtering equation with marked point process observations under mild assumptions, especially relaxing the bounded condition of stochastic intensity. Then, we derive the Poisson chaos expansion for the unnormalized filter. Based on the chaos expansion, we establish the uniqueness of solutions of the unnormalized filtering equation. Moreover, we derive the Poisson chaos expansion for the unnormalized filter density under additional conditions. To explore the computational advantage, we further construct a new consistent recursive numerical schememore » based on the truncation of the chaos density expansion for a simple case. The new algorithm divides the computations into those containing solely system coefficients and those including the observations, and assign the former off-line.« less

  16. Tissue regeneration during tissue expansion and choosing an expander

    PubMed Central

    Agrawal, K.; Agrawal, S.

    2012-01-01

    This paper reviews the various aspects of tissue regeneration during the process of tissue expansion. “Creep” and mechanical and biological “stretch” are responsible for expansion. During expansion, the epidermis thickens, the dermis thins out, vascularity improves, significant angiogenesis occurs, hair telogen phase becomes shorter and the peripheral nerves, vessels and muscle fibres lengthen. Expansion is associated with molecular changes in the tissue. Almost all these biological changes are reversible after the removal of the expander.This study is also aimed at reviewing the difficulty in deciding the volume and dimension of the expander for a defect. Basic mathematical formulae and the computer programmes for calculating the dimension of tissue expanders, although available in the literature, are not popular. A user-friendly computer programme based on the easily available Microsoft Excel spread sheet has been introduced. When we feed the area of defect and base dimension of the donor area or tissue expander, this programme calculates the volume and height of the expander. The shape of the expander is decided clinically based on the availability of the donor area and the designing of the future tissue movement. Today, tissue expansion is better understood biologically and mechanically. Clinical judgement remains indispensable in choosing the size and shape of the tissue expander. PMID:22754146

  17. The new Medicaid debate: expansion or retrenchment?

    PubMed

    2001-01-01

    Health advocates are facing a sea-change in Washington. Comprehensive federal health care reform eluded the nation under the Clinton Administration, but incremental progress through state-based Medicaid expansions and new CHIP programs was widespread, giving rise to some innovative state efforts to cover more of the uninsured. Washington's support was instrumental in those efforts, but the second Bush Administration seems intent on reversing that direction. To protect--and build upon--these nascent Medicaid efforts, advocates will have to mount careful strategies in defense of Medicaid. This States of Health looks at the dangers that may lie ahead and suggests how advocates can respond to keep Medicaid moving in the right direction.

  18. Early Impacts of the Affordable Care Act on Health Insurance Coverage in Medicaid Expansion and Non-Expansion States.

    PubMed

    Courtemanche, Charles; Marton, James; Ukert, Benjamin; Yelowitz, Aaron; Zapata, Daniela

    2017-01-01

    The Affordable Care Act (ACA) aimed to achieve nearly universal health insurance coverage in the United States through a combination of insurance market reforms, mandates, subsidies, health insurance exchanges, and Medicaid expansions, most of which took effect in 2014. This paper estimates the causal effects of the ACA on health insurance coverage in 2014 using data from the American Community Survey. We utilize difference-in-difference-in-differences models that exploit cross-sectional variation in the intensity of treatment arising from state participation in the Medicaid expansion and local area pre-ACA uninsured rates. This strategy allows us to identify the effects of the ACA in both Medicaid expansion and non-expansion states. Our preferred specification suggests that, at the average pre-treatment uninsured rate, the full ACA increased the proportion of residents with insurance by 5.9 percentage points compared to 2.8 percentage points in states that did not expand Medicaid. Private insurance expansions from the ACA were due to increases in both employer-provided and non-group coverage. The coverage gains from the full ACA were largest for those without a college degree, non-whites, young adults, unmarried individuals, and those without children in the home. We find no evidence that the Medicaid expansion crowded out private coverage.

  19. Does sulphate enrichment promote the expansion of Typha domingensis (cattail) in the Florida Everglades?

    USGS Publications Warehouse

    Li, S.; Mendelssohn, I.A.; Hao, Chen; Orem, W.H.

    2009-01-01

    1. The expansion of Typha domingensis into areas once dominated by Cladium jamaicense in the Florida Everglades has been attributed to altered hydrology and phosphorus enrichment, although increased concentrations of sulphate and phosphorus often coincide. The potential importance of hydrogen sulphide produced from sulphate in the expansion of Typha has received little attention. The present study aimed to quantify the comparative growth and photosynthetic responses of Cladium and Typha to sulphate/sulphide. 2. Laboratory experiments showed that Cladium is less tolerant of sulphide than Typha. Cladium was adversely affected at sulphide concentrations of approximately 0.22 mm, while Typha continued to grow well and appeared healthy up to 0.69 mm sulphide. 3. Experiments in field mesocosms provided strong support for species-specific differences in physiology and growth. Regardless of interstitial sulphide concentrations attained, Typha grew faster and had a higher photosynthetic capacity than Cladium. However, sulphide concentrations in the mesocosms reached only 0.18 mm which, based on the hydroponic study, was insufficient to affect the growth or photosynthetic responses of either species. Nevertheless, the upper range of sulphide (0.25-0.375 mm) in Everglades' soil is high enough, based on our results, to impact Cladium but not Typha. 4. This research supports the hypothesis that sulphide accumulation could affect plant species differentially and modify species composition. Consequently, the role of sulphate loading should be considered, in conjunction with hydroperiod, phosphorus availability and disturbances, in developing future management plans for the Everglades. ?? 2009 Blackwell Publishing Ltd.

  20. Expansive Learning in a Library: Actions, Cycles and Deviations from Instructional Intentions

    ERIC Educational Resources Information Center

    Engestrom, Yrjo; Rantavuori, Juhana; Kerosuo, Hannele

    2013-01-01

    The theory of expansive learning has been applied in a large number of studies on workplace learning and organizational change. However, detailed comprehensive analyses of entire developmental interventions based on the theory of expansive learning do not exist. Such a study is needed to examine the empirical usability and methodological rigor…

  1. The Denationalization of Education and the Expansion of the International Baccalaureate

    ERIC Educational Resources Information Center

    Resnik, Julia

    2012-01-01

    This study explores the expansion of international education focusing on International Baccalaureate (IB) schools in England, France, Israel, Argentina, and Chile. As a whole, conditions such as economic globalization and neoliberal education policies favor the expansion of IB schools. Certain national contexts and educational traditions encourage…

  2. REPORT OF THE NAEB STUDY ON THE PROPOSED EXPANSION OF THE MIDWEST PROGRAM ON AIRBORNE TELEVISION INSTRUCTION.

    ERIC Educational Resources Information Center

    BRONSON, VERNON; AND OTHERS

    A TECHNICAL REPORT WAS PREPARED COVERING THE IMPACT OF AIRBORNE TELEVISION TRANSMISSION ON LAND-BASED UHF TELEVISION ASSIGNMENT PLANS. THE REPORT RELATED TO THE PROPOSED EXPANSION PLANS OF THE MIDWEST PROGRAM ON AIRBORNE TELEVISION INSTRUCTION (MPATI). EARLIER STUDIES BY THE NATIONAL ASSOCIATION OF EDUCATIONAL BROADCASTERS (NAEB) HAD LED TO THE…

  3. Evaluating population expansion of black bears using spatial capture-recapture

    USGS Publications Warehouse

    Sun, Catherine C.; Fuller, Angela K.; Hare, Matthew P.; Hurst, Jeremy E.

    2017-01-01

    The population of American black bears (Ursus americanus) in southern New York, USA has been growing and expanding in range since the 1990s. This has motivated a need to anticipate future patterns of range expansion. We conducted a non-invasive, genetic, spatial capture-recapture (SCR) study to estimate black bear density and identify spatial patterns of population density that are potentially associated with range expansion. We collected hair samples in a 2,519-km2 study area in southern New York with barbed-wire hair snares and identified individuals and measured genetic diversity using 7 microsatellite loci and 1 sex-linked marker. We estimated a mean density of black bears in the region of 13.7 bears/100 km2, and detected a slight latitudinal gradient in density consistent with the documented range expansion. However, elevation and the amounts of forest, crop, and developed landcover types did not influence density, suggesting that bears are using a diversity of resources in this heterogeneous landscape outside their previously described distribution. These results provide the first robust baseline estimates for population density and distribution associated with different landcover types in the expanded bear range. Further, genetic diversity was comparable to that of non-expanding black bear populations in the eastern United States, and in combination with the latitudinal density gradient, suggest that the study area is not at the colonizing front of the range expansion. In addition, the diversity of landcover types used by bears in the study area implies a possible lack of constraints for further northern expansion of the black bear range. Our non-invasive, genetic, spatial capture-recapture approach has utility for studying populations of other species that may be expanding in range because SCR allows for the testing of explicit, spatial ecological hypotheses. 

  4. Preparation of Shrinkage Compensating Concrete with HCSA Expansive Agent

    NASA Astrophysics Data System (ADS)

    Li, Changcheng; Jia, Fujia

    2017-10-01

    Shrinkage compensating concrete (SCC) has become one of the best effective methods of preventing and reducing concrete cracking. SCC is prepared by HCSA high performance expansive agent for concrete which restrained expansion rate is optimized by 0.057%. Slump, compressive strength, restrained expansion rate and cracking resistance test were carried out on SCC. The results show that the initial slump of fresh SCC was about 220mm-230mm, while slump after 2 hours was 180mm-200mm. The restrained expansion rate of SCC increased with the mixing amount of expansive agent. After cured in water for 14 days, the restrained expansion rate of C35 and C40 SCC were 0.020%-0.032%. With the dosage of expansive agent increasing, restrained expansion rate of SCC increased, maximum compressive stress and cracking stress improved, cracking temperature fell, thus cracking resistance got effectively improvement.

  5. Expansion shock waves in regularized shallow-water theory

    NASA Astrophysics Data System (ADS)

    El, Gennady A.; Hoefer, Mark A.; Shearer, Michael

    2016-05-01

    We identify a new type of shock wave by constructing a stationary expansion shock solution of a class of regularized shallow-water equations that include the Benjamin-Bona-Mahony and Boussinesq equations. An expansion shock exhibits divergent characteristics, thereby contravening the classical Lax entropy condition. The persistence of the expansion shock in initial value problems is analysed and justified using matched asymptotic expansions and numerical simulations. The expansion shock's existence is traced to the presence of a non-local dispersive term in the governing equation. We establish the algebraic decay of the shock as it is gradually eroded by a simple wave on either side. More generally, we observe a robustness of the expansion shock in the presence of weak dissipation and in simulations of asymmetric initial conditions where a train of solitary waves is shed from one side of the shock.

  6. Role of axial muscles in powering mouth expansion during suction feeding in largemouth bass (Micropterus salmoides).

    PubMed

    Camp, Ariel L; Brainerd, Elizabeth L

    2014-04-15

    Suction-feeding fishes capture food by fast and forceful expansion of the mouth cavity, and axial muscles probably provide substantial power for this feeding behavior. Dorsal expansion of the mouth cavity can only be powered by the epaxial muscles, but both the sternohyoid, shortening against an immobile pectoral girdle to retract the hyoid, and the hypaxial muscles, shortening to retract both the pectoral girdle and hyoid, could contribute ventral expansion power. To determine whether hypaxial muscles generate power for ventral expansion, and the rostrocaudal extent of axial muscle shortening during suction feeding, we measured skeletal kinematics and muscle shortening in largemouth bass (Micropterus salmoides). The three-dimensional motions of the cleithrum and hyoid were measured with X-ray reconstruction of moving morphology (XROMM), and muscle shortening was measured with fluoromicrometry, wherein changes in the distance between radio-opaque intramuscular markers are measured using biplanar X-ray video recording. We found that the hypaxials generated power for ventral suction expansion, shortening (mean of 6.2 mm) to rotate the pectoral girdle caudoventrally (mean of 9.3 deg) and retract the hyoid (mean of 8.5 mm). In contrast, the sternohyoid shortened minimally (mean of 0.48 mm), functioning like a ligament to transmit hypaxial shortening to the hyoid. Hypaxial and epaxial shortening were not confined to the rostral muscle regions, but extended more than halfway down the body during suction expansion. We conclude that hypaxial and epaxial muscles are both crucial for powering mouth expansion in largemouth bass, supporting the integration of axial and cranial musculoskeletal systems for suction feeding.

  7. Mechanical feedback coordinates cell wall expansion and assembly in yeast mating morphogenesis

    PubMed Central

    2018-01-01

    The shaping of individual cells requires a tight coordination of cell mechanics and growth. However, it is unclear how information about the mechanical state of the wall is relayed to the molecular processes building it, thereby enabling the coordination of cell wall expansion and assembly during morphogenesis. Combining theoretical and experimental approaches, we show that a mechanical feedback coordinating cell wall assembly and expansion is essential to sustain mating projection growth in budding yeast (Saccharomyces cerevisiae). Our theoretical results indicate that the mechanical feedback provided by the Cell Wall Integrity pathway, with cell wall stress sensors Wsc1 and Mid2 increasingly activating membrane-localized cell wall synthases Fks1/2 upon faster cell wall expansion, stabilizes mating projection growth without affecting cell shape. Experimental perturbation of the osmotic pressure and cell wall mechanics, as well as compromising the mechanical feedback through genetic deletion of the stress sensors, leads to cellular phenotypes that support the theoretical predictions. Our results indicate that while the existence of mechanical feedback is essential to stabilize mating projection growth, the shape and size of the cell are insensitive to the feedback. PMID:29346368

  8. The genetic legacy of the expansion of Turkic-speaking nomads across Eurasia.

    PubMed

    Yunusbayev, Bayazit; Metspalu, Mait; Metspalu, Ene; Valeev, Albert; Litvinov, Sergei; Valiev, Ruslan; Akhmetova, Vita; Balanovska, Elena; Balanovsky, Oleg; Turdikulova, Shahlo; Dalimova, Dilbar; Nymadawa, Pagbajabyn; Bahmanimehr, Ardeshir; Sahakyan, Hovhannes; Tambets, Kristiina; Fedorova, Sardana; Barashkov, Nikolay; Khidiyatova, Irina; Mihailov, Evelin; Khusainova, Rita; Damba, Larisa; Derenko, Miroslava; Malyarchuk, Boris; Osipova, Ludmila; Voevoda, Mikhail; Yepiskoposyan, Levon; Kivisild, Toomas; Khusnutdinova, Elza; Villems, Richard

    2015-04-01

    The Turkic peoples represent a diverse collection of ethnic groups defined by the Turkic languages. These groups have dispersed across a vast area, including Siberia, Northwest China, Central Asia, East Europe, the Caucasus, Anatolia, the Middle East, and Afghanistan. The origin and early dispersal history of the Turkic peoples is disputed, with candidates for their ancient homeland ranging from the Transcaspian steppe to Manchuria in Northeast Asia. Previous genetic studies have not identified a clear-cut unifying genetic signal for the Turkic peoples, which lends support for language replacement rather than demic diffusion as the model for the Turkic language's expansion. We addressed the genetic origin of 373 individuals from 22 Turkic-speaking populations, representing their current geographic range, by analyzing genome-wide high-density genotype data. In agreement with the elite dominance model of language expansion most of the Turkic peoples studied genetically resemble their geographic neighbors. However, western Turkic peoples sampled across West Eurasia shared an excess of long chromosomal tracts that are identical by descent (IBD) with populations from present-day South Siberia and Mongolia (SSM), an area where historians center a series of early Turkic and non-Turkic steppe polities. While SSM matching IBD tracts (> 1cM) are also observed in non-Turkic populations, Turkic peoples demonstrate a higher percentage of such tracts (p-values ≤ 0.01) compared to their non-Turkic neighbors. Finally, we used the ALDER method and inferred admixture dates (~9th-17th centuries) that overlap with the Turkic migrations of the 5th-16th centuries. Thus, our results indicate historical admixture among Turkic peoples, and the recent shared ancestry with modern populations in SSM supports one of the hypothesized homelands for their nomadic Turkic and related Mongolic ancestors.

  9. The Genetic Legacy of the Expansion of Turkic-Speaking Nomads across Eurasia

    PubMed Central

    Metspalu, Ene; Valeev, Albert; Litvinov, Sergei; Valiev, Ruslan; Akhmetova, Vita; Balanovska, Elena; Balanovsky, Oleg; Turdikulova, Shahlo; Dalimova, Dilbar; Nymadawa, Pagbajabyn; Bahmanimehr, Ardeshir; Sahakyan, Hovhannes; Tambets, Kristiina; Fedorova, Sardana; Barashkov, Nikolay; Khidiyatova, Irina; Mihailov, Evelin; Khusainova, Rita; Damba, Larisa; Derenko, Miroslava; Malyarchuk, Boris; Osipova, Ludmila; Voevoda, Mikhail; Yepiskoposyan, Levon; Kivisild, Toomas; Khusnutdinova, Elza; Villems, Richard

    2015-01-01

    The Turkic peoples represent a diverse collection of ethnic groups defined by the Turkic languages. These groups have dispersed across a vast area, including Siberia, Northwest China, Central Asia, East Europe, the Caucasus, Anatolia, the Middle East, and Afghanistan. The origin and early dispersal history of the Turkic peoples is disputed, with candidates for their ancient homeland ranging from the Transcaspian steppe to Manchuria in Northeast Asia. Previous genetic studies have not identified a clear-cut unifying genetic signal for the Turkic peoples, which lends support for language replacement rather than demic diffusion as the model for the Turkic language’s expansion. We addressed the genetic origin of 373 individuals from 22 Turkic-speaking populations, representing their current geographic range, by analyzing genome-wide high-density genotype data. In agreement with the elite dominance model of language expansion most of the Turkic peoples studied genetically resemble their geographic neighbors. However, western Turkic peoples sampled across West Eurasia shared an excess of long chromosomal tracts that are identical by descent (IBD) with populations from present-day South Siberia and Mongolia (SSM), an area where historians center a series of early Turkic and non-Turkic steppe polities. While SSM matching IBD tracts (> 1cM) are also observed in non-Turkic populations, Turkic peoples demonstrate a higher percentage of such tracts (p-values ≤ 0.01) compared to their non-Turkic neighbors. Finally, we used the ALDER method and inferred admixture dates (~9th–17th centuries) that overlap with the Turkic migrations of the 5th–16th centuries. Thus, our results indicate historical admixture among Turkic peoples, and the recent shared ancestry with modern populations in SSM supports one of the hypothesized homelands for their nomadic Turkic and related Mongolic ancestors. PMID:25898006

  10. Thermal Expansion Behavior of Hot-Pressed Engineered Matrices

    NASA Technical Reports Server (NTRS)

    Raj, S. V.

    2016-01-01

    Advanced engineered matrix composites (EMCs) require that the coefficient of thermal expansion (CTE) of the engineered matrix (EM) matches those of the fiber reinforcements as closely as possible in order to reduce thermal compatibility strains during heating and cooling of the composites. The present paper proposes a general concept for designing suitable matrices for long fiber reinforced composites using a rule of mixtures (ROM) approach to minimize the global differences in the thermal expansion mismatches between the fibers and the engineered matrix. Proof-of-concept studies were conducted to demonstrate the validity of the concept.

  11. Quantitative analysis of urban sprawl in Tripoli using Pearson's Chi-Square statistics and urban expansion intensity index

    NASA Astrophysics Data System (ADS)

    Al-sharif, Abubakr A. A.; Pradhan, Biswajeet; Zulhaidi Mohd Shafri, Helmi; Mansor, Shattri

    2014-06-01

    Urban expansion is a spatial phenomenon that reflects the increased level of importance of metropolises. The remotely sensed data and GIS have been widely used to study and analyze the process of urban expansions and their patterns. The capital of Libya (Tripoli) was selected to perform this study and to examine its urban growth patterns. Four satellite imageries of the study area in different dates (1984, 1996, 2002 and 2010) were used to conduct this research. The main goal of this work is identification and analyzes the urban sprawl of Tripoli metropolitan area. Urban expansion intensity index (UEII) and degree of freedom test were used to analyze and assess urban expansions in the area of study. The results show that Tripoli has sprawled urban expansion patterns; high urban expansion intensity index; and its urban development had high degree of freedom according to its urban expansion history during the time period (1984-2010). However, the novel proposed hypothesis used for zones division resulted in very good insight understanding of urban expansion direction and the effect of the distance from central business of district (CBD).

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

    ERIC Educational Resources Information Center

    Sari, Emel; Kilic, Mehmet Akif

    2009-01-01

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

  13. Class, Gender, and School Expansion in France: A Four-Systems Comparison.

    ERIC Educational Resources Information Center

    Garnier, Maurice A.; Hage, Jerald

    1991-01-01

    Discusses a study of the effects of material incentives and institutionalized values upon the expansion of secondary school systems in France. Reports that class was more important than gender in determining expansion because state policies placed greater emphasis on emphasized class in determining supply. Concludes that state policy reinforced…

  14. Plasma plume expansion dynamics in nanosecond Nd:YAG laserosteotome

    NASA Astrophysics Data System (ADS)

    Abbasi, Hamed; Rauter, Georg; Guzman, Raphael; Cattin, Philippe C.; Zam, Azhar

    2018-02-01

    In minimal invasive laser osteotomy precise information about the ablation process can be obtained with LIBS in order to avoid carbonization, or cutting of wrong types of tissue. Therefore, the collecting fiber for LIBS needs to be optimally placed in narrow cavities in the endoscope. To determine this optimal placement, the plasma plume expansion dynamics in ablation of bone tissue by the second harmonic of a nanosecond Nd:YAG laser at 532 nm has been studied. The laserinduced plasma plume was monitored in different time delays, from one nanosecond up to one hundred microseconds. Measurements were performed using high-speed gated illumination imaging. The expansion features were studied using illumination of the overall visible emission by using a gated intensified charged coupled device (ICCD). The camera was capable of having a minimum gate width (Optical FWHM) of 3 ns and the timing resolution (minimum temporal shift of the gate) of 10 ps. The imaging data were used to generate position-time data of the luminous plasma-front. Moreover, the velocity of the plasma plume expansion was studied based on the time-resolved intensity data. By knowing the plasma plume profile over time, the optimum position (axial distance from the laser spot) of the collecting fiber and optimal time delay (to have the best signal to noise ratio) in spatial-resolved and time-resolved laser-induced breakdown spectroscopy (LIBS) can be determined. Additionally, the function of plasma plume expansion could be used to study the shock wave of the plasma plume.

  15. Pleistocene to holocene expansion of the black-belt cichlid in Central America, Vieja maculicauda (Teleostei: Cichlidae)

    PubMed Central

    Ginger, Luke; Cage, Marcy; David, Kyle T.; Chakrabarty, Prosanta; Johnston, Mark; Matamoros, Wilfredo A.

    2017-01-01

    The distributions of many Northern Hemisphere organisms have been influenced by fluctuations in sea level and climatic conditions during Pleistocene interglacial periods. These cycles are associated with range contraction and refugia for northern-distributed organisms as a response to glaciers. However, lower sea levels in the tropics and sub-tropics created available habitat for expansion of the ranges of freshwater organisms. The goal of this study was to use ecological niche modeling to test the hypothesis of north to south range expansion of Vieja maculicauda associated with Pleistocene glacial cycles. Understanding the biogeography of this widespread species may help us better understand the geology and interconnectivity of Central American freshwaters. Occurrence data for V. maculicauda was based on georeferencing of all museum records of specimens recovered from FishNet2. General patterns of phylogeographic structure were assessed with mtDNA. Present day niche models were generated and subsequently projected onto paleoclimatic maps of the region during the Last Interglacial, Last Glacial Maximum, and mid-Holocene. Phylogenetic analysis of mtDNA sequence data showed no phylogeographic structure throughout the range of this widespread species. Present day niche models were congruent with the observed distribution of V. maculicauda in Central America. Results showed a lack of suitable freshwater habitat in northern Central America and Mexico during the Last Interglacial, with greatest range expansion during the Last Glacial Maximum and mid-Holocene. Results support the hypothesis of a north to south range expansion of V. maculicauda associated with glacial cycles. The wide distribution of this species compared to other closely related cichlids indicates the latter did not respond to the degree of V. maculicauda in expansion of their distributions. Future work aimed at comparisons with other species and modeling of future climatic scenarios will be a fruitful

  16. Review of vortex tube expansion in vapour compression refrigeration system

    NASA Astrophysics Data System (ADS)

    Liu, Yefeng; Yu, Jun

    2018-05-01

    A vortex tube expansion device replacing the throttle valve is proposed to improve the efficiency of vapour compression refrigeration cycle by reducing the loss of irreversibility in expansion process. The vortex tube is well-suited for these applications because it is simple, compact, light, quiet. Thus, this paper presents an overview of the thermodynamic analysis of vapour compression refrigeration cycle with vortex tube expansion device using different refrigerants. The paper also reviews the experiments and the calculations presented in previous studies on temperature separation in the vortex tube. The temperature separation mechanism and the flow-field inside the vortex tubes is explored by measuring the pressure, velocity, and temperature fields.

  17. TESTING THE EFFECTS OF EXPANSION ON SOLAR WIND TURBULENCE

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

    Vech, Daniel; Chen, Christopher H K, E-mail: dvech@umich.edu

    2016-11-20

    We present a multi-spacecraft approach to test the predictions of recent studies on the effect of solar wind expansion on the radial spectral, variance, and local 3D anisotropies of the turbulence. We found that on small scales (5000–10,000 km) the power levels of the B-trace structure functions do not depend on the sampling direction with respect to the radial suggesting that on this scale the effect of expansion is small possibly due to fast turbulent timescales. On larger scales (110–135 R{sub E}), the fluctuations of the radial magnetic field component are reduced by ∼20% compared to the transverse (perpendicular tomore » radial) ones, which could be due to expansion confining the fluctuations into the plane perpendicular to radial. For the local 3D spectral anisotropy, the B-trace structure functions showed dependence on the sampling direction with respect to radial. The anisotropy in the perpendicular plane is reduced when the increments are taken perpendicular with respect to radial, which could be an effect of expansion.« less

  18. Expansion shock waves in regularized shallow-water theory

    PubMed Central

    El, Gennady A.; Shearer, Michael

    2016-01-01

    We identify a new type of shock wave by constructing a stationary expansion shock solution of a class of regularized shallow-water equations that include the Benjamin–Bona–Mahony and Boussinesq equations. An expansion shock exhibits divergent characteristics, thereby contravening the classical Lax entropy condition. The persistence of the expansion shock in initial value problems is analysed and justified using matched asymptotic expansions and numerical simulations. The expansion shock's existence is traced to the presence of a non-local dispersive term in the governing equation. We establish the algebraic decay of the shock as it is gradually eroded by a simple wave on either side. More generally, we observe a robustness of the expansion shock in the presence of weak dissipation and in simulations of asymmetric initial conditions where a train of solitary waves is shed from one side of the shock. PMID:27279780

  19. Skeletal and dental changes following surgically assisted rapid palatal expansion.

    PubMed

    Byloff, Friedrich K; Mossaz, Claude F

    2004-08-01

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

  20. Concentric ring flywheel without expansion separators

    DOEpatents

    Kuklo, Thomas C.

    1999-01-01

    A concentric ring flywheel wherein the adjacent rings are configured to eliminate the need for differential expansion separators between the adjacent rings. This is accomplished by forming a circumferential step on an outer surface of an inner concentric ring and forming a matching circumferential step on the inner surface of an adjacent outer concentric ring. During operation the circumferential steps allow the rings to differentially expand due to the difference in the radius of the rings without the formation of gaps therebetween, thereby eliminating the need for expansion separators to take up the gaps formed by differential expansion.

  1. 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 Central

    2013-01-01

    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

  2. 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

  3. Thermal expansion properties of Ho2Fe16.5Cr0.5

    NASA Astrophysics Data System (ADS)

    Dan, Shovan; Mukherjee, S.; Mazumdar, Chandan; Ranganathan, R.

    2018-04-01

    We report the thermal expansion behavior of Ho2Fe16.5Cr0.5 compound in the range of temperature 13-483 K, using structural parameters obtained by analyzing temperature dependent x-ray diffraction (XRD) patterns. From 13 K to 300 K, the compound shows negligible thermal expansion having the coefficient of volume expansion (αV) ∼ 10-6 K -1. The thermal expansion behavior of the studied compound can be explained by the role of magnetovolume effect (MVE) below ferrimagnetic ordering temperature (394 K), in addition to normal phononic contribution. Fe sublattice contribute to MVE, whereas both the rare earth and Fe sublattice determine the value of saturation magnetization.

  4. Short-term expansion of glacial lakes in the Himalayas

    NASA Astrophysics Data System (ADS)

    Nagai, H.; Tadono, T.

    2017-12-01

    A glacial lake outburst flood (GLOF) is a serious mountainous hazard that is related to glacial shrinkage. Despite technical developments in satellite-based lake expansion monitoring, small glacial lakes were collapsed in Bhutan in June 2015 and in Nepal in May 2017. Relatively heavy rainfall was reported downstream just before the floods. Does a large amount of short-term precipitation have a possibility of triggering a GLOF? To answer this question, the temporal change in the glacial lake area is assessed by means of satellite-based synthetic aperture radar, coupled with satellite-derived spatial and temporal distribution of precipitation to evaluate the contribution of rainfall in glacial lake expansion. The Phased Array type L-band Synthetic Aperture Radar-2 (PALSAR-2) observed the Mande Chu river basin in central Bhutan on Aug 11, 2016. Glacial lakes were manually delineated from the orthorectified backscatter amplitude image. They were compared with those delineated from the old satellite images of ALOS ( 2011), PALSAR-2 (2014-2016), and Landsat-8 (2016). The temporal and spatial distributions of precipitation (2010-2016) are obtained from the Global Satellite Mapping of Precipitation (GSMaP) data (10-km spatial / 60-min. temporal resolutions), calibrated by in situ rain gauges (GSMap_RNL/MVL). The outlines of 11 glacial lakes in the study site were successfully traced from 2011 to 2016; rapid expansion was recorded especially in the period between March and July 2016. In this period, exceeding 500 mm of the total amount of precipitation is recorded by GSMaP, whereas the mean precipitation amount is 300-400 mm in the previous years. This implies that relatively larger precipitation occurred in 2016, which is related to the short-term expansion of the glacial lakes. The rapid expansion of smaller lakes can be explained by their relatively shallow depths, which is sensitive to the increase in inflow water volume. This study highlights the importance of high

  5. Workplace expansion, long-term sickness absence, and hospital admission.

    PubMed

    Westerlund, Hugo; Ferrie, Jane; Hagberg, Jan; Jeding, Kerstin; Oxenstierna, Gabriel; Theorell, Töres

    2004-04-10

    Downsizing has in previous studies, as well as in public debate, been associated with increased sickness absence. No studies have, however, looked at the long-term relation between workplace expansion and morbidity. We investigated exposure to personnel change during 1991-96 in relation to long-term (90 days or longer) medically certified sickness absence and hospital admission for specified diagnoses during 1997-99 in 24?036 participants with a complete employment record in the biennial national Swedish Work Environment Surveys from 1989 to the end of 1999. Accumulated exposure to large expansion (> or =18% per year) was related to an increased risk of long-term sickness absence (odds ratio 1.07 [95% CI 1.01-1.13], p=0.013) and hospital admission (1.09 [1.02-1.16], p=0.017). In this context, odds ratio signifies the change in odds for each additional year of exposure, varying from 0 to 6. Moderate expansion (> or =8% and <18% per year), was associated with a decreased risk of admission (0.91 [0.84-0.98], p=0.012). Moderate downsizing (> or =8% and <18% per year) was associated with an increased risk of sickness absence (1.07 [1.02-1.12], p=0.003). The strongest association between large expansion and sickness absence was in women in the public sector (1.18 [1.08-1.30], p=0.0002), corresponding to an odds ratio of 2.77 [1.62-4.74] between full exposure (all 6 years) and no exposure. This study confirms earlier findings that downsizing is associated with health risks. It also shows that repeated exposure to rapid personnel expansion, possibly connected with centralisation of functions, statistically predicts long-term sickness absence and hospital admission. Although no conclusions about causal pathways can be drawn from our results, this exposure should be considered in future studies, policy making, and occupational health care practice.

  6. [Instrumentation support in respiratory kinesiotherapy].

    PubMed

    Vandevenne, A; Sergysels, R; Ravez, P; Worth, H; De Coster, A

    1988-01-01

    The points of impact of instrumental support in respiratory physiotherapy are numerous; they concern primarily the pulmonary expansion, bronchial drainage and function of respiratory muscles. The pulmonary expansion may be helped by incitant spirometry and either intermittent or continuous positive pressure respiration, or indirectly by the utilisation of respiration against resistance (expiratory bottles, masks with uni-directional valves and expiratory resistances etc.). These different techniques may be used in the presence of instability of the respiratory units, secondary to an alteration of surfactant or to closure of the small airways induced by a transitory reduction (in the post-operative period) or permanent reduction (such as parietal wall disease of mechanical or neuro-muscular origin) of the functional residual capacity (CRF). If the continuous positive airway pressure (CPAP) seems particularly helpful for the CRF to recover to the pre-operative level it also appears on the contrary as the least efficacious technique to increase trans-pulmonary pressure. The instrumental support for bronchial drainage may theoretically affect the tension activity of the transport (instrumental help in the pulmonary expansion and in hyperventilation), muco-ciliary transport (external parietal vibration or internal vibrations applied to the upper airways), the biphasic flow (expiratory assistance by negative pressure and humidifiers). The function of the respiratory muscles may in certain cases be improved by the use of abdominal pneumatic cuirasses, by hyperventilation exercises in an isocapnoeic milieu or in breathing exercises against an additional inspiratory or expiratory resistance. If the physiological foundation of mechanical support in respiratory education may be frequently identified, the clinical results reported in the literature are often contradictory.

  7. Does Avicennia germinans expansion alter salt marsh nitrogen removal capacity?

    NASA Astrophysics Data System (ADS)

    Tatariw, C.; Kleinhuizen, A.; Rajan, S.; Flournoy, N.; Sobecky, P.; Mortazavi, B.

    2017-12-01

    Plant species expansion poses risks to ecosystem services through alterations to plant-microbiome interactions associated with changes to key microbial drivers such as organic carbon (C) substrates, nitrogen (N) availability, and rhizosphere-associated microbial communities. In the northern Gulf of Mexico (GOM), warming winter temperatures associated with climate change have promoted Avicennia germinans (black mangrove) expansion into salt marshes. To date, there is limited knowledge regarding the effects of mangrove expansion on vital ecosystem services such as N cycling in the northern GOM. We designed a field-based study to determine the potential effects of mangrove expansion on salt marsh N biogeochemical cycling in the Spartina alterniflora dominated Chandeleur Islands (LA, USA). We used a combination of process rate measurements and metadata to: 1) Determine the impact of mangrove expansion on salt marsh denitrification and dissimilatory nitrate reduction to ammonium (DNRA), with the goal of quantifying losses or gains in ecosystem services; and 2) identify the mechanisms driving changes in ecosystem services to improve predictions about the impacts of mangrove expansion on salt marsh functional resiliency. The pneumatophore root structure of A. germinans is efficient at delivering oxygen (O2) to sediment, which can promote coupled nitrification-denitrification and decrease sulfide inhibition. We hypothesized that increased sediment O2, when coupled with cooler soil temperatures caused by plant shading, will favor denitrification instead of the DNRA process. An increase in sediment O2, as well as higher N content of A. germinans litter, will also result in a shift in the microbial community. Initial findings indicated that the denitrification pathway dominates over DNRA regardless of vegetation type, with average denitrification rates of 30.1 µmol N kg-1 h-1 versus average DNRA rates of 8.5 µmol N kg-1 h-1. However, neither denitrification nor DNRA rates

  8. 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.

  9. Linking admiration and adoration to self-expansion: different ways to enhance one's potential.

    PubMed

    Schindler, Ines; Paech, Juliane; Löwenbrück, Fabian

    2015-01-01

    How is admiration different from adoration? We provided one answer to this question by examining the pathways through which admiration and adoration linked to self-expansion in a questionnaire and an experimental (autobiographical recall of emotion episodes) study. Both emotions were associated with increased potential efficacy to accomplish goals (i.e., self-expansion), but different action tendencies accounted for these links. While our emotion inductions did not successfully distinguish between admiration and adoration, we could statistically disentangle their effects through mediator models. In both studies, self-reported admiration linked to self-expansion through the tendency to emulate admired others. Adoration related to self-expansion through the tendency to affiliate with adored others. These findings were obtained after controlling for other emotions in response to the target person (awe, love, hope, benign envy) and mutuality of the relationship. Our findings also suggest that considering specific emotions (rather than undifferentiated positive affect) helps uncover different pathways to self-expansion.

  10. Multimodal airway evaluation in growing patients after rapid maxillary expansion.

    PubMed

    Fastuca, R; Meneghel, M; Zecca, P A; Mangano, F; Antonello, M; Nucera, R; Caprioglio, A

    2015-06-01

    The objective of this study was to evaluate the airway volume of growing patients combining a morphological approach using cone beam computed tomography associated with functional data obtained by polysomnography examination after rapid maxillary expansion treatment. 22 Caucasian patients (mean age 8.3±0.9 years) undergoing rapid maxillary expansion with Haas type expander banded on second deciduous upper molars were enrolled for this prospective study. Cone beam computed tomography scans and polysomnography exams were collected before placing the appliance (T0) and after 12 months (T1). Image processing with airway volume computing and analyses of oxygen saturation and apnoea/hypopnoea index were performed. Airway volume, oxygen saturation and apnea/hypopnea index underwent significant increase over time. However, no significant correlation was seen between their increases. The rapid maxillary expansion treatment induced significant increases in the total airway volume and respiratory performance. Functional respiratory parameters should be included in studies evaluating the RME treatment effects on the respiratory performance.

  11. Social costs of expanding access to evidence-based supported employment: concepts and interpretive review of evidence.

    PubMed

    Salkever, David

    2013-02-01

    A recent policy analysis argued that expanding access to evidence-based supported employment can provide savings in major components of social costs. This article extends the scope of this policy analysis by placing the argument within a recently developed economic framework for social cost-effectiveness analysis that defines a program's social cost impact as its effect on net consumption of all goods and services. A total of 27 studies over the past two decades are reviewed to synthesize evidence of the social cost impacts of expanding access to the individual placement and support model of supported employment (IPS-SE). Most studies have focused primarily on agency costs of providing IPS-SE services, cost offsets when clients shift from "traditional" rehabilitation to IPS-SE, and impacts on clients' earnings. Because costs and cost offsets are similar in magnitude, incremental costs of expanding services to persons who would otherwise receive traditional services are probably small or even negative. The population served by an expansion could be sizable, but the feasibility of a policy targeting IPS-SE expansion in this way has yet to be demonstrated. IPS-SE has positive impacts on competitive job earnings, but these may not fully translate into social cost offsets. Additional empirical support is needed for the argument that large-scale expansion would yield substantial mental health treatment cost offsets. Other gaps in evidence of policy impacts include take-up rate estimates, cost impact estimates from longer-term studies (exceeding two years), and longer-term studies of whether IPS-SE prevents younger clients from becoming recipients of Supplemental Security Income or Social Security Disability Insurance

  12. Quantifying urban growth patterns in Hanoi using landscape expansion modes and time series spatial metrics.

    PubMed

    Nong, Duong H; Lepczyk, Christopher A; Miura, Tomoaki; Fox, Jefferson M

    2018-01-01

    Urbanization has been driven by various social, economic, and political factors around the world for centuries. Because urbanization continues unabated in many places, it is crucial to understand patterns of urbanization and their potential ecological and environmental impacts. Given this need, the objectives of our study were to quantify urban growth rates, growth modes, and resultant changes in the landscape pattern of urbanization in Hanoi, Vietnam from 1993 to 2010 and to evaluate the extent to which the process of urban growth in Hanoi conformed to the diffusion-coalescence theory. We analyzed the spatiotemporal patterns and dynamics of the built-up land in Hanoi using landscape expansion modes, spatial metrics, and a gradient approach. Urbanization was most pronounced in the periods of 2001-2006 and 2006-2010 at a distance of 10 to 35 km around the urban center. Over the 17 year period urban expansion in Hanoi was dominated by infilling and edge expansion growth modes. Our findings support the diffusion-coalescence theory of urbanization. The shift of the urban growth areas over time and the dynamic nature of the spatial metrics revealed important information about our understanding of the urban growth process and cycle. Furthermore, our findings can be used to evaluate urban planning policies and aid in urbanization issues in rapidly urbanizing countries.

  13. Quantifying urban growth patterns in Hanoi using landscape expansion modes and time series spatial metrics

    PubMed Central

    Lepczyk, Christopher A.; Miura, Tomoaki; Fox, Jefferson M.

    2018-01-01

    Urbanization has been driven by various social, economic, and political factors around the world for centuries. Because urbanization continues unabated in many places, it is crucial to understand patterns of urbanization and their potential ecological and environmental impacts. Given this need, the objectives of our study were to quantify urban growth rates, growth modes, and resultant changes in the landscape pattern of urbanization in Hanoi, Vietnam from 1993 to 2010 and to evaluate the extent to which the process of urban growth in Hanoi conformed to the diffusion-coalescence theory. We analyzed the spatiotemporal patterns and dynamics of the built-up land in Hanoi using landscape expansion modes, spatial metrics, and a gradient approach. Urbanization was most pronounced in the periods of 2001–2006 and 2006–2010 at a distance of 10 to 35 km around the urban center. Over the 17 year period urban expansion in Hanoi was dominated by infilling and edge expansion growth modes. Our findings support the diffusion-coalescence theory of urbanization. The shift of the urban growth areas over time and the dynamic nature of the spatial metrics revealed important information about our understanding of the urban growth process and cycle. Furthermore, our findings can be used to evaluate urban planning policies and aid in urbanization issues in rapidly urbanizing countries. PMID:29734346

  14. RTEL1 Inhibits Trinucleotide Repeat Expansions and Fragility

    PubMed Central

    Frizzell, Aisling; Nguyen, Jennifer H.G.; Petalcorin, Mark I.R.; Turner, Katherine D.; Boulton, Simon J.; Freudenreich, Catherine H.; Lahue, Robert S.

    2018-01-01

    SUMMARY Human RTEL1 is an essential, multifunctional helicase that maintains telomeres, regulates homologous recombination, and helps prevent bone marrow failure. Here, we show that RTEL1 also blocks trinucleotide repeat expansions, the causal mutation for 17 neurological diseases. Increased expansion frequencies of (CTG·CAG) repeats occurred in human cells following knockdown of RTEL1, but not the alternative helicase Fbh1, and purified RTEL1 efficiently unwound triplet repeat hairpins in vitro. The expansion-blocking activity of RTEL1 also required Rad18 and HLTF, homologs of yeast Rad18 and Rad5. These findings are reminiscent of budding yeast Srs2, which inhibits expansions, unwinds hairpins, and prevents triplet-repeat-induced chromosome fragility. Accordingly, we found expansions and fragility were suppressed in yeast srs2 mutants expressing RTEL1, but not Fbh1. We propose that RTEL1 serves as a human analog of Srs2 to inhibit (CTG·CAG) repeat expansions and fragility, likely by unwinding problematic hairpins. PMID:24561255

  15. 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…

  16. 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)

  17. Investigation of the expansion rate scaling of plasmas in the Electron Diffusion Gauge experiment

    NASA Astrophysics Data System (ADS)

    Morrison, Kyle A.; Davidson, Ronald C.; Paul, Stephen F.; Jenkins, Thomas G.

    2002-01-01

    The expansion of the Electron Diffusion Gauge (EDG) pure electron plasma due to collisions with background neutral gas atoms is characterized by the pressure and magnetic field scaling of the profile expansion rate (d/dt). Data obtained at higher background gas pressures [1] than previously studied [2] is presented. The measured expansion rate in the higher pressure regime is found to be in good agreement with the classical estimate of the expansion rate [3].

  18. Expansive Learning as Production of Community

    ERIC Educational Resources Information Center

    Morck, Line Lerche

    2010-01-01

    This article contributes a framework for analyzing learning as an expansive process in which persons come to partly transcend marginalization. Expansive learning is a kind of learning that partly transcends marginalization through changed participation and recognition by others of participants in their changed communities. This article draws on…

  19. 14 CFR 23.969 - Fuel tank expansion space.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Fuel tank expansion space. 23.969 Section 23.969 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT....969 Fuel tank expansion space. Each fuel tank must have an expansion space of not less than two...

  20. 14 CFR 23.969 - Fuel tank expansion space.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Fuel tank expansion space. 23.969 Section 23.969 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT....969 Fuel tank expansion space. Each fuel tank must have an expansion space of not less than two...

  1. 14 CFR 23.969 - Fuel tank expansion space.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Fuel tank expansion space. 23.969 Section 23.969 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT....969 Fuel tank expansion space. Each fuel tank must have an expansion space of not less than two...

  2. 14 CFR 23.969 - Fuel tank expansion space.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Fuel tank expansion space. 23.969 Section 23.969 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT....969 Fuel tank expansion space. Each fuel tank must have an expansion space of not less than two...

  3. 14 CFR 23.969 - Fuel tank expansion space.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Fuel tank expansion space. 23.969 Section 23.969 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT....969 Fuel tank expansion space. Each fuel tank must have an expansion space of not less than two...

  4. Research progress on expansive soil cracks under changing environment.

    PubMed

    Shi, Bei-xiao; Zheng, Cheng-feng; Wu, Jin-kun

    2014-01-01

    Engineering problems shunned previously rise to the surface gradually with the activities of reforming the natural world in depth, the problem of expansive soil crack under the changing environment becoming a control factor of expansive soil slope stability. The problem of expansive soil crack has gradually become a research hotspot, elaborates the occurrence and development of cracks from the basic properties of expansive soil, and points out the role of controlling the crack of expansive soil strength. We summarize the existing research methods and results of expansive soil crack characteristics. Improving crack measurement and calculation method and researching the crack depth measurement, statistical analysis method, crack depth and surface feature relationship will be the future direction.

  5. 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.

  6. Intra-hydrogel culture prevents transformation of mesenchymal stem cells induced by monolayer expansion.

    PubMed

    Jiang, Tongmeng; Liu, Junting; Ouyang, Yiqiang; Wu, Huayu; Zheng, Li; Zhao, Jinmin; Zhang, Xingdong

    2018-05-01

    In this study, we report that the intra-hydrogel culture system mitigates the transformation of mesenchymal stem cells (MSCs) induced by two-dimensional (2D) expansion. MSCs expanded in monolayer culture prior to encapsulation in collagen hydrogels (group eMSCs-CH) featured impaired stemness in chondrogenesis, comparing with the freshly isolated bone marrow mononuclear cells seeded directly in collagen hydrogels (group fMSCs-CH). The molecular mechanism of the in vitro expansion-triggered damage to MSCs was detected through genome-wide microarray analysis. Results indicated that pathways such as proteoglycans in cancer and pathways in cancer expansion were highly enriched in eMSCs-CH. And multiple up-regulated oncoma-associated genes were verified in eMSCs-CH compared with fMSCs-CH, indicating that expansion in vitro triggered cellular transformation was associated with signaling pathways related to tumorigenicity. Besides, focal adhesion (FA) and mitogen-activated protein kinase (MAPK) signaling pathways were also involved in in vitro expansion, indicating restructuring of the cell architecture. Thus, monolayer expansion in vitro may contribute to vulnerability of MSCs through the regulation of FA and MAPK. This study indicates that intra-hydrogel culture can mitigate the monolayer expansion induced transformation of MSCs and maintain the uniformity of the stem cells, which is a viable in vitro culture system for stem cell therapy.

  7. Thermal expansion behavior of LDEF metal matrix composites

    NASA Technical Reports Server (NTRS)

    Le, Tuyen D.; Steckel, Gary L.

    1993-01-01

    The thermal expansion behavior of Long Duration Exposure Facility (LDEF) metal matrix composite materials was studied by (1) analyzing the flight data that was recorded on orbit to determine the effects of orbital time and heating/cooling rates on the performance of the composite materials, and (2) characterizing and comparing the thermal expansion behavior of post-flight LDEF and lab-control samples. The flight data revealed that structures in space are subjected to nonuniform temperature distributions, and thermal conductivity of a material is an important factor in establishing a uniform temperature distribution and avoiding thermal distortion. The flight and laboratory data showed that both Gr/Al and Gr/Mg composites were stabilized after prolonged thermal cycling on orbit. However, Gr/Al composites showed more stable thermal expansion behavior than Gr/Mg composites and offer advantages for space structures particularly where very tight thermal stability requirements in addition to high material performance must be met.

  8. Medicaid Expansion Affects Rural And Urban Hospitals Differently.

    PubMed

    Kaufman, Brystana G; Reiter, Kristin L; Pink, George H; Holmes, George M

    2016-09-01

    Rural hospitals differ from urban hospitals in many ways. For example, rural hospitals are more reliant on public payers and have lower operating margins. In addition, enrollment in the health insurance Marketplaces of the Affordable Care Act (ACA) has varied across rural and urban areas. This study employed a difference-in-differences approach to evaluate the average effect of Medicaid expansion in 2014 on payer mix and profitability for urban and rural hospitals, controlling for secular trends. For both types of hospitals, we found that Medicaid expansion was associated with increases in Medicaid-covered discharges. However, the increases in Medicaid revenue were greater among rural hospitals than urban hospitals, and the decrease in the proportion of costs for uncompensated care were greater among urban hospitals than rural hospitals. This preliminary analysis of the early effects of Medicaid expansion suggests that its financial impacts may be different for hospitals in urban and rural locations. Project HOPE—The People-to-People Health Foundation, Inc.

  9. Exact semiclassical expansions for one-dimensional quantum oscillators

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

    Delabaere, E.; Dillinger, H.; Pham, F.

    1997-12-01

    A set of rules is given for dealing with WKB expansions in the one-dimensional analytic case, whereby such expansions are not considered as approximations but as exact encodings of wave functions, thus allowing for analytic continuation with respect to whichever parameters the potential function depends on, with an exact control of small exponential effects. These rules, which include also the case when there are double turning points, are illustrated on various examples, and applied to the study of bound state or resonance spectra. In the case of simple oscillators, it is thus shown that the Rayleigh{endash}Schr{umlt o}dinger series is Borelmore » resummable, yielding the exact energy levels. In the case of the symmetrical anharmonic oscillator, one gets a simple and rigorous justification of the Zinn-Justin quantization condition, and of its solution in terms of {open_quotes}multi-instanton expansions.{close_quotes} {copyright} {ital 1997 American Institute of Physics.}« less

  10. Expansion in chickpea (Cicer arietinum L.) seed during soaking and cooking

    NASA Astrophysics Data System (ADS)

    Sayar, Sedat; Turhan, Mahir; Köksel, Hamit

    2016-01-01

    The linear and volumetric expansion of chickpea seeds during water absorption at 20, 30, 50, 70, 85 and 100°C was studied. Length, width and thickness of chickpea seeds linearly increased with the increase in moisture content at all temperatures studied, where the greatest increase was found in length. Two different mathematical approaches were used for the determination of the expansion coefficients. The plots of the both linear and volumetric expansion coefficients versus temperature exhibited two linear lines, the first one was through 20, 30 and 50ºC and the second one was trough 70, 85 and 100ºC. The crossing point (58ºC) of these lines was very close to the gelatinisation temperature (60ºC) of chickpea starch.

  11. Effects of exosome-like vesicles on cumulus expansion in pigs in vitro.

    PubMed

    Matsuno, Yuta; Onuma, Asuka; Fujioka, Yoshie A; Yasuhara, Kazuma; Fujii, Wataru; Naito, Kunihiko; Sugiura, Koji

    2017-02-16

    Cell-secreted vesicles, such as exosomes, have recently been recognized as mediators of cell communication. A recent study in cattle showed the involvement of exosome-like vesicles in the control of cumulus expansion, a prerequisite process for normal ovulation; however, whether this is the case in other mammalian species is not known. Therefore, this study aimed to examine the presence of exosome-like vesicles in ovarian follicles and their effects on cumulus expansion in vitro in pigs. The presence of exosome-like vesicles in porcine follicular fluid (pFF) was confirmed by transmission electron microscopic observation, the detection of marker proteins, and RNA profiles specific to exosomes. Fluorescently labeled exosome-like vesicles isolated from pFF were incorporated into both cumulus and mural granulosa cells in vitro. Exosome-like vesicles were not capable of inducing cumulus expansion to a degree comparable to that induced by follicle-stimulating hormone (FSH). Moreover, exosome-like vesicles had no significant effects on the expression levels of transcripts required for the normal expansion process (HAS2, TNFAIP6, and PTGS2). Interestingly, FSH-induced expression of HAS2 and TNFAIP6 mRNA, but not of PTGS2 mRNA, was significantly increased by the presence of exosome-like vesicles; however, the degree of FSH-induced expansion was not affected. In addition, porcine exosome-like vesicles had no significant effects on the expansion of mouse cumulus-oocyte complexes. Collectively, the present results suggest that exosome-like vesicles are present in pFF, but they are not efficient in inducing cumulus expansion in pigs.

  12. Effects of exosome-like vesicles on cumulus expansion in pigs in vitro

    PubMed Central

    MATSUNO, Yuta; ONUMA, Asuka; FUJIOKA, Yoshie A; YASUHARA, Kazuma; FUJII, Wataru; NAITO, Kunihiko; SUGIURA, Koji

    2017-01-01

    Cell-secreted vesicles, such as exosomes, have recently been recognized as mediators of cell communication. A recent study in cattle showed the involvement of exosome-like vesicles in the control of cumulus expansion, a prerequisite process for normal ovulation; however, whether this is the case in other mammalian species is not known. Therefore, this study aimed to examine the presence of exosome-like vesicles in ovarian follicles and their effects on cumulus expansion in vitro in pigs. The presence of exosome-like vesicles in porcine follicular fluid (pFF) was confirmed by transmission electron microscopic observation, the detection of marker proteins, and RNA profiles specific to exosomes. Fluorescently labeled exosome-like vesicles isolated from pFF were incorporated into both cumulus and mural granulosa cells in vitro. Exosome-like vesicles were not capable of inducing cumulus expansion to a degree comparable to that induced by follicle-stimulating hormone (FSH). Moreover, exosome-like vesicles had no significant effects on the expression levels of transcripts required for the normal expansion process (HAS2, TNFAIP6, and PTGS2). Interestingly, FSH-induced expression of HAS2 and TNFAIP6 mRNA, but not of PTGS2 mRNA, was significantly increased by the presence of exosome-like vesicles; however, the degree of FSH-induced expansion was not affected. In addition, porcine exosome-like vesicles had no significant effects on the expansion of mouse cumulus-oocyte complexes. Collectively, the present results suggest that exosome-like vesicles are present in pFF, but they are not efficient in inducing cumulus expansion in pigs. PMID:28163264

  13. The Effect of Medicaid Expansion on Delivery of Finger and Thumb Replantation Care to Medicaid Beneficiaries and the Uninsured.

    PubMed

    Giladi, Aviram M; Aliu, Oluseyi; Chung, Kevin C

    2015-11-01

    Despite advances in replantation, over 80 percent of finger and thumb amputation injuries in the United States result in revision amputation. Although numerous factors contribute to this, disparities in access and delivery of replantation care play a substantial role. With ongoing Medicaid expansion under the Affordable Care Act, it is prudent to understand whether expansion of coverage changes use of replantation care. The authors used the 2001 Medicaid expansion in New York State to evaluate changes in replantation for Medicaid beneficiaries and the uninsured. Data for patients having undergone replantation between 1998 and 2006 were obtained from the New York State Inpatient Database. The authors used an interrupted time series to evaluate the effect of Medicaid expansion on the probability that Medicaid beneficiaries or uninsured patients underwent replantation. Census data were used for population-adjusted case volume analysis. After expansion, the likelihood of Medicaid as the primary payer for replantation increased 0.0059 percent per quarter, reaching a 1.7 percent increase 5 years after expansion. With population-based analysis, this indicates that Medicaid covered 12 additional replantation cases in New York State annually. After expansion, 11 fewer of the replantation cases in New York State each year were provided to patients without health care coverage. Medicaid expansion resulted in a modest but significant increase in replantation for Medicaid beneficiaries. In addition, fewer patients that underwent replantation remained uninsured. Considering the substantial cost and effort burden of replantation, these findings support the benefits of Medicaid expansion on delivery and payer coverage of replantation.

  14. PLANNING MODELS FOR URBAN WATER SUPPLY EXPANSION. VOLUME 1. PLANNING FOR THE EXPANSION OF REGIONAL WATER SUPPLY SYSTEMS

    EPA Science Inventory

    A three-volume report was developed relative to the modelling of investment strategies for regional water supply planning. Volume 1 is the study of capacity expansion over time. Models to aid decision making for the deterministic case are presented, and a planning process under u...

  15. The Expansive Executive. Report Number 147. Second Edition.

    ERIC Educational Resources Information Center

    Kaplan, Robert E.

    This report seeks to understand executive leadership by focusing on a character type called "expansive." Expansive character revolves around mastery of tasks and a continual desire to accomplish. In the report, several goals are featured: to define what expansive character is; to discuss its origins; to show how moderate versus extreme…

  16. 36 CFR 72.42 - Expansion and new development.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 1 2012-07-01 2012-07-01 false Expansion and new development..., Rehabilitation and Innovation § 72.42 Expansion and new development. (a) Expansion. Because the UPARR Program is... distressed neighborhoods. (b) New development. For purposes of this program, new development is defined as...

  17. 77 FR 38070 - Office of Refugee Resettlement; Announcing the Award of a Single-Source Program Expansion...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-26

    ... Supplemental Grant for Unaccompanied Alien Children's Shelter Care to Baptist Children and Family Services... Unaccompanied Alien Children's Program. SUMMARY: The Administration for Children and Families (ACF), Office of... will support the expansion of bed capacity to meet the number of unaccompanied alien children referrals...

  18. The heavy quark expansion of QCD

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

    Falk, A.F.

    1997-06-01

    These lectures contain an elementary introduction to heavy quark symmetry and the heavy quark expansion. Applications such as the expansion of heavy meson decay constants and the treatment of inclusive and exclusive semileptonic B decays are included. Heavy hadron production via nonperturbative fragmentation processes is also discussed. 54 refs., 7 figs.

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

    PubMed Central

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

    2017-01-01

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

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

    PubMed

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

    2016-08-01

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

  1. Hydration and Thermal Expansion in Anatase Nanoparticles

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

    Zhu, He; Li, Qiang; Ren, Yang

    A tunable thermal expansion is reported in nanosized anatase by taking advantage of surface hydration. The coefficient of thermal expansion of 4 nm TiO2 along a-axis is negative with a hydrated surface and is positive without a hydrated surface. High-energy synchrotron X-ray pair distribution function analysis combined with ab initio calculations on the specific hydrated surface are carried out to reveal the local structure distortion that is responsible for the unusual negative thermal expansion.

  2. Estimation of regional lung expansion via 3D image registration

    NASA Astrophysics Data System (ADS)

    Pan, Yan; Kumar, Dinesh; Hoffman, Eric A.; Christensen, Gary E.; McLennan, Geoffrey; Song, Joo Hyun; Ross, Alan; Simon, Brett A.; Reinhardt, Joseph M.

    2005-04-01

    A method is described to estimate regional lung expansion and related biomechanical parameters using multiple CT images of the lungs, acquired at different inflation levels. In this study, the lungs of two sheep were imaged utilizing a multi-detector row CT at different lung inflations in the prone and supine positions. Using the lung surfaces and the airway branch points for guidance, a 3D inverse consistent image registration procedure was used to match different lung volumes at each orientation. The registration was validated using a set of implanted metal markers. After registration, the Jacobian of the deformation field was computed to express regional expansion or contraction. The regional lung expansion at different pressures and different orientations are compared.

  3. Breaking the Link between Environmental Degradation and Oil Palm Expansion: A Method for Enabling Sustainable Oil Palm Expansion

    PubMed Central

    Smit, Hans Harmen; Meijaard, Erik; van der Laan, Carina; Mantel, Stephan; Budiman, Arif; Verweij, Pita

    2013-01-01

    Land degradation is a global concern. In tropical areas it primarily concerns the conversion of forest into non-forest lands and the associated losses of environmental services. Defining such degradation is not straightforward hampering effective reduction in degradation and use of already degraded lands for more productive purposes. To facilitate the processes of avoided degradation and land rehabilitation, we have developed a methodology in which we have used international environmental and social sustainability standards to determine the suitability of lands for sustainable agricultural expansion. The method was developed and tested in one of the frontiers of agricultural expansion, West Kalimantan province in Indonesia. The focus was on oil palm expansion, which is considered as a major driver for deforestation in tropical regions globally. The results suggest that substantial changes in current land-use planning are necessary for most new plantations to comply with international sustainability standards. Through visualizing options for sustainable expansion with our methodology, we demonstrate that the link between oil palm expansion and degradation can be broken. Application of the methodology with criteria and thresholds similar to ours could help the Indonesian government and the industry to achieve its pro-growth, pro-job, pro-poor and pro-environment development goals. For sustainable agricultural production, context specific guidance has to be developed in areas suitable for expansion. Our methodology can serve as a template for designing such commodity and country specific tools and deliver such guidance. PMID:24039700

  4. Modal resonant dynamics of cables with a flexible support: A modulated diffraction problem

    NASA Astrophysics Data System (ADS)

    Guo, Tieding; Kang, Houjun; Wang, Lianhua; Liu, Qijian; Zhao, Yueyu

    2018-06-01

    Modal resonant dynamics of cables with a flexible support is defined as a modulated (wave) diffraction problem, and investigated by asymptotic expansions of the cable-support coupled system. The support-cable mass ratio, which is usually very large, turns out to be the key parameter for characterizing cable-support dynamic interactions. By treating the mass ratio's inverse as a small perturbation parameter and scaling the cable tension properly, both cable's modal resonant dynamics and the flexible support dynamics are asymptotically reduced by using multiple scale expansions, leading finally to a reduced cable-support coupled model (i.e., on a slow time scale). After numerical validations of the reduced coupled model, cable-support coupled responses and the flexible support induced coupling effects on the cable, are both fully investigated, based upon the reduced model. More explicitly, the dynamic effects on the cable's nonlinear frequency and force responses, caused by the support-cable mass ratio, the resonant detuning parameter and the support damping, are carefully evaluated.

  5. Numerical Study of Interaction of a Vortical Density Inhomogeneity with Shock and Expansion Waves

    NASA Technical Reports Server (NTRS)

    Povitsky, A.; Ofengeim, D.

    1998-01-01

    We studied the interaction of a vortical density inhomogeneity (VDI) with shock and expansion waves. We call the VDI the region of concentrated vorticity (vortex) with a density different from that of ambiance. Non-parallel directions of the density gradient normal to the VDI surface and the pressure gradient across a shock wave results in an additional vorticity. The roll-up of the initial round VDI towards a non-symmetrical shape is studied numerically. Numerical modeling of this interaction is performed by a 2-D Euler code. The use of an adaptive unstructured numerical grid makes it possible to obtain high accuracy and capture regions of induced vorticity with a moderate overall number of mesh points. For the validation of the code, the computational results are compared with available experimental results and good agreement is obtained. The interaction of the VDI with a propagating shock wave is studied for a range of initial and induced circulations and obtained flow patterns are presented. The splitting of the VDI develops into the formation of a non-symmetrical vortex pair and not in a set of vortices. A method for the analytical computation of an overall induced circulation Gamma(sub 1) as a result of the interaction of a moving VDI with a number of waves is proposed. Simplified, approximated, expressions for Gamma(sub 1) are derived and their accuracy is discussed. The splitting of the VDI passing through the Prandtl-Meyer expansion wave is studied numerically. The obtained VDI patterns are compared to those for the interaction of the VDI with a propagating shock wave for the same values of initial and induced circulations. These patterns have similar shapes for corresponding time moments.

  6. 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.

  7. On the error in the nucleus-centered multipolar expansion of molecular electron density and its topology: A direct-space computational study.

    PubMed

    Michael, J Robert; Koritsanszky, Tibor

    2017-05-28

    The convergence of nucleus-centered multipolar expansion of the quantum-chemical electron density (QC-ED), gradient, and Laplacian is investigated in terms of numerical radial functions derived by projecting stockholder atoms onto real spherical harmonics at each center. The partial sums of this exact one-center expansion are compared with the corresponding Hansen-Coppens pseudoatom (HC-PA) formalism [Hansen, N. K. and Coppens, P., "Testing aspherical atom refinements on small-molecule data sets," Acta Crystallogr., Sect. A 34, 909-921 (1978)] commonly utilized in experimental electron density studies. It is found that the latter model, due to its inadequate radial part, lacks pointwise convergence and fails to reproduce the local topology of the target QC-ED even at a high-order expansion. The significance of the quantitative agreement often found between HC-PA-based (quadrupolar-level) experimental and extended-basis QC-EDs can thus be challenged.

  8. On the error in the nucleus-centered multipolar expansion of molecular electron density and its topology: A direct-space computational study

    NASA Astrophysics Data System (ADS)

    Michael, J. Robert; Koritsanszky, Tibor

    2017-05-01

    The convergence of nucleus-centered multipolar expansion of the quantum-chemical electron density (QC-ED), gradient, and Laplacian is investigated in terms of numerical radial functions derived by projecting stockholder atoms onto real spherical harmonics at each center. The partial sums of this exact one-center expansion are compared with the corresponding Hansen-Coppens pseudoatom (HC-PA) formalism [Hansen, N. K. and Coppens, P., "Testing aspherical atom refinements on small-molecule data sets," Acta Crystallogr., Sect. A 34, 909-921 (1978)] commonly utilized in experimental electron density studies. It is found that the latter model, due to its inadequate radial part, lacks pointwise convergence and fails to reproduce the local topology of the target QC-ED even at a high-order expansion. The significance of the quantitative agreement often found between HC-PA-based (quadrupolar-level) experimental and extended-basis QC-EDs can thus be challenged.

  9. Expansion of postoperative pneumothorax and pneumomediastinum: determining when it is safe to fly.

    PubMed

    Szymanski, Trevor J; Jaklitsch, Michael T; Jacobson, Francine; Mullen, Gary J; Ferrigno, Massimo

    2010-04-01

    The possibility of expansion of pneumothorax (PTX) and/or pneumomediastinum (PMED) during commercial flights makes air travel after thoracic surgery particularly worrisome. Guidelines from the Aerospace Medical Association (AsMA) suggest delaying air travel 2 to 3 wk following uncomplicated thoracic surgery and 1 wk following radiographic resolution of PTX; they also state that PTX is an "absolute contraindication" to air travel. However, both AsMA guidelines and thoracic surgeons' recommendations for postoperative air travel require further examination. We reviewed the literature looking for evidence supporting official guidelines and conducted a survey of U.S. thoracic surgeons about their recommendations for air travel by patients with postoperative PTX and/or PMED. We found no experimental evidence supporting the AsMA guidelines. Of the 68 thoracic surgeons who returned our questionnaire, 44% recommended that patients wait variable periods of time of up to 42 d (13.8 +/- 11.6 d) following complete resolution of PTX prior to air travel, while 46% of them allowed their patients to fly with some degree of PTX. Following mediastinoscopy, 76.9% of the surgeons allowed their patients to fly without delay, even with PMED. The only adverse in-flight event reported was a case of thoracic pain during ascent. A wide variability exists among thoracic surgeons regarding their recommendations for air travel by patients with postoperative PTX and/or PMED. Both AsMA guidelines and surgeons' recommendations should rely more on scientific evidence. Studies of PTX and PMED expansion during simulated flight are needed to develop better guidelines.

  10. Convergence of Legendre Expansion of Doppler-Broadened Double Differential Elastic Scattering Cross Section

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

    Arbanas, Goran; Dunn, Michael E; Larson, Nancy M

    2012-01-01

    Convergence properties of Legendre expansion of a Doppler-broadened double-differential elastic neutron scattering cross section of {sup 238}U near the 6.67 eV resonance at temperature 10{sup 3} K are studied. A variance of Legendre expansion from a reference Monte Carlo computation is used as a measure of convergence and is computed for as many as 15 terms in the Legendre expansion. When the outgoing energy equals the incoming energy, it is found that the Legendre expansion converges very slowly. Therefore, a supplementary method of computing many higher-order terms is suggested and employed for this special case.

  11. Expansive Soil Crack Depth under Cumulative Damage

    PubMed Central

    Shi, Bei-xiao; Chen, Sheng-shui; Han, Hua-qiang; Zheng, Cheng-feng

    2014-01-01

    The crack developing depth is a key problem to slope stability of the expansive soil and its project governance and the crack appears under the roles of dry-wet cycle and gradually develops. It is believed from the analysis that, because of its own cohesion, the expansive soil will have a certain amount of deformation under pulling stress but without cracks. The soil body will crack only when the deformation exceeds the ultimate tensile strain that causes cracks. And it is also believed that, due to the combined effect of various environmental factors, particularly changes of the internal water content, the inherent basic physical properties of expansive soil are weakened, and irreversible cumulative damages are eventually formed, resulting in the development of expansive soil cracks in depth. Starting from the perspective of volumetric strain that is caused by water loss, considering the influences of water loss rate and dry-wet cycle on crack developing depth, the crack developing depth calculation model which considers the water loss rate and the cumulative damages is established. Both the proposal of water loss rate and the application of cumulative damage theory to the expansive soil crack development problems try to avoid difficulties in matrix suction measurement, which will surely play a good role in promoting and improving the research of unsaturated expansive soil. PMID:24737974

  12. Cognitive and clinical characteristics of patients with amyotrophic lateral sclerosis carrying a C9orf72 repeat expansion: a population-based cohort study.

    PubMed

    Byrne, Susan; Elamin, Marwa; Bede, Peter; Shatunov, Aleksey; Walsh, Cathal; Corr, Bernie; Heverin, Mark; Jordan, Norah; Kenna, Kevin; Lynch, Catherine; McLaughlin, Russell L; Iyer, Parameswaran Mahadeva; O'Brien, Caoimhe; Phukan, Julie; Wynne, Brona; Bokde, Arun L; Bradley, Daniel G; Pender, Niall; Al-Chalabi, Ammar; Hardiman, Orla

    2012-03-01

    Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease of upper and lower motor neurons, associated with frontotemporal dementia (FTD) in about 14% of incident cases. We assessed the frequency of the recently identified C9orf72 repeat expansion in familial and apparently sporadic cases of ALS and characterised the cognitive and clinical phenotype of patients with this expansion. A population-based register of patients with ALS has been in operation in Ireland since 1995, and an associated DNA bank has been in place since 1999. 435 representative DNA samples from the bank were screened using repeat-primed PCR for the presence of a GGGGCC repeat expansion in C9orf72. We assessed clinical, cognitive, behavioural, MRI, and survival data from 191 (44%) of these patients, who comprised a population-based incident group and had previously participated in a longitudinal study of cognitive and behavioural changes in ALS. Samples from the DNA bank included 49 cases of known familial ALS and 386 apparently sporadic cases. Of these samples, 20 (41%) cases of familial ALS and 19 (5%) cases of apparently sporadic ALS had the C9orf72 repeat expansion. Of the 191 patients for whom phenotype data were available, 21 (11%) had the repeat expansion. Age at disease onset was lower in patients with the repeat expansion (mean 56·3 [SD 8·3] years) than in those without (61·3 [10·6] years; p=0·043). A family history of ALS or FTD was present in 18 (86%) of those with the repeat expansion. Patients with the repeat expansion had significantly more co-morbid FTD than patients without the repeat (50%vs 12%), and a distinct pattern of non-motor cortex changes on high-resolution 3 T magnetic resonance structural neuroimaging. Age-matched univariate analysis showed shorter survival (20 months vs 26 months) in patients with the repeat expansion. Multivariable analysis showed an increased hazard rate of 1·9 (95% 1·1-3·7; p=0·035) in those patients with the repeat

  13. Estimates of expansion time scales

    NASA Astrophysics Data System (ADS)

    Jones, E. M.

    Monte Carlo simulations of the expansion of a spacefaring civilization show that descendants of that civilization should be found near virtually every useful star in the Galaxy in a time much less than the current age of the Galaxy. Only extreme assumptions about local population growth rates, emigration rates, or ship ranges can slow or halt an expansion. The apparent absence of extraterrestrials from the solar system suggests that no such civilization has arisen in the Galaxy.

  14. Nanoscale imaging of clinical specimens using pathology-optimized expansion microscopy

    PubMed Central

    Zhao, Yongxin; Bucur, Octavian; Irshad, Humayun; Chen, Fei; Weins, Astrid; Stancu, Andreea L.; Oh, Eun-Young; DiStasio, Marcello; Torous, Vanda; Glass, Benjamin; Stillman, Isaac E.; Schnitt, Stuart J.; Beck, Andrew H.; Boyden, Edward S.

    2017-01-01

    Expansion microscopy (ExM), a method for improving the resolution of light microscopy by physically expanding the specimen, has not been applied to clinical tissue samples. Here we report a clinically optimized form of ExM that supports nanoscale imaging of human tissue specimens that have been fixed with formalin, embedded in paraffin, stained with hematoxylin and eosin (H&E), and/or fresh frozen. The method, which we call expansion pathology (ExPath), converts clinical samples into an ExM-compatible state, then applies an ExM protocol with protein anchoring and mechanical homogenization steps optimized for clinical samples. ExPath enables ~70 nm resolution imaging of diverse biomolecules in intact tissues using conventional diffraction-limited microscopes, and standard antibody and fluorescent DNA in situ hybridization reagents. We use ExPath for optical diagnosis of kidney minimal-change disease, which previously required electron microscopy (EM), and demonstrate high-fidelity computational discrimination between early breast neoplastic lesions that to date have challenged human judgment. ExPath may enable the routine use of nanoscale imaging in pathology and clinical research. PMID:28714966

  15. Nanoscale imaging of clinical specimens using pathology-optimized expansion microscopy.

    PubMed

    Zhao, Yongxin; Bucur, Octavian; Irshad, Humayun; Chen, Fei; Weins, Astrid; Stancu, Andreea L; Oh, Eun-Young; DiStasio, Marcello; Torous, Vanda; Glass, Benjamin; Stillman, Isaac E; Schnitt, Stuart J; Beck, Andrew H; Boyden, Edward S

    2017-08-01

    Expansion microscopy (ExM), a method for improving the resolution of light microscopy by physically expanding a specimen, has not been applied to clinical tissue samples. Here we report a clinically optimized form of ExM that supports nanoscale imaging of human tissue specimens that have been fixed with formalin, embedded in paraffin, stained with hematoxylin and eosin, and/or fresh frozen. The method, which we call expansion pathology (ExPath), converts clinical samples into an ExM-compatible state, then applies an ExM protocol with protein anchoring and mechanical homogenization steps optimized for clinical samples. ExPath enables ∼70-nm-resolution imaging of diverse biomolecules in intact tissues using conventional diffraction-limited microscopes and standard antibody and fluorescent DNA in situ hybridization reagents. We use ExPath for optical diagnosis of kidney minimal-change disease, a process that previously required electron microscopy, and we demonstrate high-fidelity computational discrimination between early breast neoplastic lesions for which pathologists often disagree in classification. ExPath may enable the routine use of nanoscale imaging in pathology and clinical research.

  16. A phase cell cluster expansion for Euclidean field theories

    NASA Astrophysics Data System (ADS)

    Battle, Guy A., III; Federbush, Paul

    1982-08-01

    We adapt the cluster expansion first used to treat infrared problems for lattice models (a mass zero cluster expansion) to the usual field theory situation. The field is expanded in terms of special block spin functions and the cluster expansion given in terms of the expansion coefficients (phase cell variables); the cluster expansion expresses correlation functions in terms of contributions from finite coupled subsets of these variables. Most of the present work is carried through in d space time dimensions (for φ24 the details of the cluster expansion are pursued and convergence is proven). Thus most of the results in the present work will apply to a treatment of φ34 to which we hope to return in a succeeding paper. Of particular interest in this paper is a substitute for the stability of the vacuum bound appropriate to this cluster expansion (for d = 2 and d = 3), and a new method for performing estimates with tree graphs. The phase cell cluster expansions have the renormalization group incorporated intimately into their structure. We hope they will be useful ultimately in treating four dimensional field theories.

  17. RTEL1 inhibits trinucleotide repeat expansions and fragility.

    PubMed

    Frizzell, Aisling; Nguyen, Jennifer H G; Petalcorin, Mark I R; Turner, Katherine D; Boulton, Simon J; Freudenreich, Catherine H; Lahue, Robert S

    2014-03-13

    Human RTEL1 is an essential, multifunctional helicase that maintains telomeres, regulates homologous recombination, and helps prevent bone marrow failure. Here, we show that RTEL1 also blocks trinucleotide repeat expansions, the causal mutation for 17 neurological diseases. Increased expansion frequencies of (CTG⋅CAG) repeats occurred in human cells following knockdown of RTEL1, but not the alternative helicase Fbh1, and purified RTEL1 efficiently unwound triplet repeat hairpins in vitro. The expansion-blocking activity of RTEL1 also required Rad18 and HLTF, homologs of yeast Rad18 and Rad5. These findings are reminiscent of budding yeast Srs2, which inhibits expansions, unwinds hairpins, and prevents triplet-repeat-induced chromosome fragility. Accordingly, we found expansions and fragility were suppressed in yeast srs2 mutants expressing RTEL1, but not Fbh1. We propose that RTEL1 serves as a human analog of Srs2 to inhibit (CTG⋅CAG) repeat expansions and fragility, likely by unwinding problematic hairpins. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  18. Term Dependence: Truncating the Bahadur Lazarsfeld Expansion.

    ERIC Educational Resources Information Center

    Losee, Robert M., Jr.

    1994-01-01

    Studies the performance of probabilistic information retrieval systems using differing statistical dependence assumptions when estimating the probabilities inherent in the retrieval model. Experimental results using the Bahadur Lazarsfeld expansion on the Cystic Fibrosis database are discussed that suggest that incorporating term dependence…

  19. Blunt-Body Aerothermodynamic Database from High-Enthalpy CO2 Testing in an Expansion Tunnel

    NASA Technical Reports Server (NTRS)

    Hollis, Brian R.; Prabhu, Dinesh K.; Maclean, Matthew; Dufrene, Aaron

    2016-01-01

    An extensive database of heating, pressure, and flow field measurements on a 70-deg sphere-cone blunt body geometry in high-enthalpy, CO2 flow has been generated through testing in an expansion tunnel. This database is intended to support development and validation of computational tools and methods to be employed in the design of future Mars missions. The test was conducted in an expansion tunnel in order to avoid uncertainties in the definition of free stream conditions noted in previous studies performed in reflected shock tunnels. Data were obtained across a wide range of test velocity/density conditions that produced various physical phenomena of interest, including laminar and transitional/turbulent boundary layers, non-reacting to completely dissociated post-shock gas composition and shock-layer radiation. Flow field computations were performed at the test conditions and comparisons were made with the experimental data. Based on these comparisons, it is recommended that computational uncertainties on surface heating and pressure, for laminar, reacting-gas environments can be reduced to +/-10% and +/-5%, respectively. However, for flows with turbulence and shock-layer radiation, there were not sufficient validation-quality data obtained in this study to make any conclusions with respect to uncertainties, which highlights the need for further research in these areas.

  20. Anisotropic thermal expansion in a metal-organic framework.

    PubMed

    Madsen, Solveig Røgild; Lock, Nina; Overgaard, Jacob; Iversen, Bo Brummerstedt

    2014-06-01

    Ionothermal reaction between Mn(II)(acetate)2·4H2O and 1,3,5-benzenetricarboxylic acid (H3BTC) in either of the two ionic liquids 1-ethyl-3-methylimidazolium bromide (EMIMBr) and 1-ethyl-3-methylimidazolium tosylate (EMIMOTs) resulted in the formation of the new metal-organic framework (MOF) EMIM[Mn(II)BTC] (BTC = 1,3,5-benzenetricarboxylate). The compound crystallizes in the orthorhombic space group Pbca with unit-cell parameters of a = 14.66658 (12), b = 12.39497 (9), c = 16.63509 (14) Å at 100 K. Multi-temperature single-crystal (15-340 K) and powder X-ray diffraction studies (100-400 K) reveal strongly anisotropic thermal expansion properties. The linear thermal expansion coefficients, αL(l), attain maximum values at 400 K along the a- and b-axis, with αL(a) = 115 × 10(-6) K(-1) and αL(b) = 75 × 10(-6) K(-1). At 400 K a negative thermal expansion coefficient of -40 × 10(-6) K(-1) is observed along the c-axis. The thermal expansion is coupled to a continuous deformation of the framework, which causes the structure to expand in two directions. Due to the rigidity of the linker, the expansion in the ab plane causes the network to contract along the c-axis. Hirshfeld surface analysis has been used to describe the interaction between the framework structure and the EMIM cation that resides within the channel. This reveals a number of rather weak interactions and one governing hydrogen-bonding interactions.

  1. A Simulator for the Respiratory Tree in Healthy Subjects Derived from Continued Fractions Expansions

    NASA Astrophysics Data System (ADS)

    Muntean, Ionuţ; Ionescu, Clara; Naşcu, Ioan

    2009-04-01

    Taking into account the self-similar recurrent geometrical structure of the human respiratory tree, the total respiratory impedance can be represented using an electrical equivalent of a ladder network model. In this paper, the parameters of the respiratory tree are employed in simulation, based on clinical insight and morphology. Once the transfer function of the total input impedance model is calculated, it is further interpreted in its continued fraction expansion form. The purpose is to compare the ladder network structure with the continuous fraction expansion form of the impedance. The results are supporting the theory of fractional-order impedance appearance (also known as constant-phase behaviour) and help understanding the mathematical and morphological basis for constructing a physiology-based simulator of the human lungs.

  2. Asymptotic Expansion of β Matrix Models in the One-cut Regime

    NASA Astrophysics Data System (ADS)

    Borot, G.; Guionnet, A.

    2013-01-01

    We prove the existence of a 1/ N expansion to all orders in β matrix models with a confining, offcritical potential corresponding to an equilibrium measure with a connected support. Thus, the coefficients of the expansion can be obtained recursively by the "topological recursion" derived in Chekhov and Eynard (JHEP 0612:026, 2006). Our method relies on the combination of a priori bounds on the correlators and the study of Schwinger-Dyson equations, thanks to the uses of classical complex analysis techniques. These a priori bounds can be derived following (Boutet de Monvel et al. in J Stat Phys 79(3-4):585-611, 1995; Johansson in Duke Math J 91(1):151-204, 1998; Kriecherbauer and Shcherbina in Fluctuations of eigenvalues of matrix models and their applications, 2010) or for strictly convex potentials by using concentration of measure (Anderson et al. in An introduction to random matrices, Sect. 2.3, Cambridge University Press, Cambridge, 2010). Doing so, we extend the strategy of Guionnet and Maurel-Segala (Ann Probab 35:2160-2212, 2007), from the hermitian models ( β = 2) and perturbative potentials, to general β models. The existence of the first correction in 1/ N was considered in Johansson (1998) and more recently in Kriecherbauer and Shcherbina (2010). Here, by taking similar hypotheses, we extend the result to all orders in 1/ N.

  3. Territorial expansion and primary state formation

    PubMed Central

    Spencer, Charles S.

    2010-01-01

    A major research problem in anthropology is the origin of the state and its bureaucratic form of governance. Of particular importance for evaluating theories of state origins are cases of primary state formation, whereby a first-generation state evolves without contact with any preexisting states. A general model of this process, the territorial-expansion model, is presented and assessed with archaeological data from six areas where primary states emerged in antiquity: Mesoamerica, Peru, Egypt, Mesopotamia, the Indus Valley, and China. In each case, the evidence shows a close correspondence in time between the first appearance of state institutions and the earliest expansion of the state's political-economic control to regions lying more than a day's round-trip from the capital. Although additional research will add detail and clarity to the empirical record, the results to date are consistent with the territorial-expansion model, which argues that the success of such long-distance expansion not only demanded the bureaucratization of central authority but also helped provide the resources necessary to underwrite this administrative transformation. PMID:20385804

  4. Thermal expansion anomaly regulated by entropy.

    PubMed

    Liu, Zi-Kui; Wang, Yi; Shang, ShunLi

    2014-11-13

    Thermal expansion, defined as the temperature dependence of volume under constant pressure, is a common phenomenon in nature and originates from anharmonic lattice dynamics. However, it has been poorly understood how thermal expansion can show anomalies such as colossal positive, zero, or negative thermal expansion (CPTE, ZTE, or NTE), especially in quantitative terms. Here we show that changes in configurational entropy due to metastable micro(scopic)states can lead to quantitative prediction of these anomalies. We integrate the Maxwell relation, statistic mechanics, and first-principles calculations to demonstrate that when the entropy is increased by pressure, NTE occurs such as in Invar alloy (Fe3Pt, for example), silicon, ice, and water, and when the entropy is decreased dramatically by pressure, CPTE is expected such as in anti-Invar cerium, ice and water. Our findings provide a theoretic framework to understand and predict a broad range of anomalies in nature in addition to thermal expansion, which may include gigantic electrocaloric and electromechanical responses, anomalously reduced thermal conductivity, and spin distributions.

  5. Territorial expansion and primary state formation.

    PubMed

    Spencer, Charles S

    2010-04-20

    A major research problem in anthropology is the origin of the state and its bureaucratic form of governance. Of particular importance for evaluating theories of state origins are cases of primary state formation, whereby a first-generation state evolves without contact with any preexisting states. A general model of this process, the territorial-expansion model, is presented and assessed with archaeological data from six areas where primary states emerged in antiquity: Mesoamerica, Peru, Egypt, Mesopotamia, the Indus Valley, and China. In each case, the evidence shows a close correspondence in time between the first appearance of state institutions and the earliest expansion of the state's political-economic control to regions lying more than a day's round-trip from the capital. Although additional research will add detail and clarity to the empirical record, the results to date are consistent with the territorial-expansion model, which argues that the success of such long-distance expansion not only demanded the bureaucratization of central authority but also helped provide the resources necessary to underwrite this administrative transformation.

  6. Thermal Expansion Anomaly Regulated by Entropy

    NASA Astrophysics Data System (ADS)

    Liu, Zi-Kui; Wang, Yi; Shang, Shunli

    2014-11-01

    Thermal expansion, defined as the temperature dependence of volume under constant pressure, is a common phenomenon in nature and originates from anharmonic lattice dynamics. However, it has been poorly understood how thermal expansion can show anomalies such as colossal positive, zero, or negative thermal expansion (CPTE, ZTE, or NTE), especially in quantitative terms. Here we show that changes in configurational entropy due to metastable micro(scopic)states can lead to quantitative prediction of these anomalies. We integrate the Maxwell relation, statistic mechanics, and first-principles calculations to demonstrate that when the entropy is increased by pressure, NTE occurs such as in Invar alloy (Fe3Pt, for example), silicon, ice, and water, and when the entropy is decreased dramatically by pressure, CPTE is expected such as in anti-Invar cerium, ice and water. Our findings provide a theoretic framework to understand and predict a broad range of anomalies in nature in addition to thermal expansion, which may include gigantic electrocaloric and electromechanical responses, anomalously reduced thermal conductivity, and spin distributions.

  7. Relict or colonizer? Extinction and range expansion of penguins in southern New Zealand

    PubMed Central

    Boessenkool, Sanne; Austin, Jeremy J.; Worthy, Trevor H.; Scofield, Paul; Cooper, Alan; Seddon, Philip J.; Waters, Jonathan M.

    2008-01-01

    Recent human expansion into the Pacific initiated a dramatic avian extinction crisis, and surviving taxa are typically interpreted as declining remnants of previously abundant populations. As a case in point, New Zealand's endangered yellow-eyed penguin (Megadyptes antipodes) is widely considered to have been more abundant and widespread in the past. By contrast, our genetic and morphological analyses of prehistoric, historic and modern penguin samples reveal that this species expanded its range to the New Zealand mainland only in the last few hundred years. This range expansion was apparently facilitated by the extinction of M. antipodes' previously unrecognized sister species following Polynesian settlement in New Zealand. Based on combined genetic and morphological data, we describe this new penguin species, the first known to have suffered human-mediated extinction. The range expansion of M. antipodes so soon after the extinction of its sister species supports a historic paradigmatic shift in New Zealand Polynesian culture. Additionally, such a dynamic biological response to human predation reveals a surprising and less recognized potential for species to have benefited from the extinction of their ecologically similar sister taxa and highlights the complexity of large-scale extinction events. PMID:19019791

  8. Combined KIT and FGFR2b Signaling Regulates Epithelial Progenitor Expansion during Organogenesis

    PubMed Central

    Lombaert, Isabelle M.A.; Abrams, Shaun R.; Li, Li; Eswarakumar, Veraragavan P.; Sethi, Aditya J.; Witt, Robert L.; Hoffman, Matthew P.

    2013-01-01

    Summary Organ formation and regeneration require epithelial progenitor expansion to engineer, maintain, and repair the branched tissue architecture. Identifying the mechanisms that control progenitor expansion will inform therapeutic organ (re)generation. Here, we discover that combined KIT and fibroblast growth factor receptor 2b (FGFR2b) signaling specifically increases distal progenitor expansion during salivary gland organogenesis. FGFR2b signaling upregulates the epithelial KIT pathway so that combined KIT/FGFR2b signaling, via separate AKT and mitogen-activated protein kinase (MAPK) pathways, amplifies FGFR2b-dependent transcription. Combined KIT/FGFR2b signaling selectively expands the number of KIT+K14+SOX10+ distal progenitors, and a genetic loss of KIT signaling depletes the distal progenitors but also unexpectedly depletes the K5+ proximal progenitors. This occurs because the distal progenitors produce neurotrophic factors that support gland innervation, which maintains the proximal progenitors. Furthermore, a rare population of KIT+FGFR2b+ cells is present in adult glands, in which KIT signaling also regulates epithelial-neuronal communication during homeostasis. Our findings provide a framework to direct regeneration of branched epithelial organs. PMID:24371813

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

    PubMed

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

    2007-01-01

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

  10. Thermal expansion of quaternary nitride coatings

    NASA Astrophysics Data System (ADS)

    Tasnádi, Ferenc; Wang, Fei; Odén, Magnus; Abrikosov, Igor A.

    2018-04-01

    The thermal expansion coefficient of technologically relevant multicomponent cubic nitride alloys are predicted using the Debye model with ab initio elastic constants calculated at 0 K and an isotropic approximation for the Grüneisen parameter. Our method is benchmarked against measured thermal expansion of TiN and Ti(1-x)Al x N as well as against results of molecular dynamics simulations. We show that the thermal expansion coefficients of Ti(1-x-y)X y Al x N (X  =  Zr, Hf, Nb, V, Ta) solid solutions monotonously increase with the amount of alloying element X at all temperatures except for Zr and Hf, for which they instead decrease for y≳ 0.5 .

  11. Recent Northern Hemisphere tropical expansion primarily driven by black carbon and tropospheric ozone.

    PubMed

    Allen, Robert J; Sherwood, Steven C; Norris, Joel R; Zender, Charles S

    2012-05-16

    Observational analyses have shown the width of the tropical belt increasing in recent decades as the world has warmed. This expansion is important because it is associated with shifts in large-scale atmospheric circulation and major climate zones. Although recent studies have attributed tropical expansion in the Southern Hemisphere to ozone depletion, the drivers of Northern Hemisphere expansion are not well known and the expansion has not so far been reproduced by climate models. Here we use a climate model with detailed aerosol physics to show that increases in heterogeneous warming agents--including black carbon aerosols and tropospheric ozone--are noticeably better than greenhouse gases at driving expansion, and can account for the observed summertime maximum in tropical expansion. Mechanistically, atmospheric heating from black carbon and tropospheric ozone has occurred at the mid-latitudes, generating a poleward shift of the tropospheric jet, thereby relocating the main division between tropical and temperate air masses. Although we still underestimate tropical expansion, the true aerosol forcing is poorly known and could also be underestimated. Thus, although the insensitivity of models needs further investigation, black carbon and tropospheric ozone, both of which are strongly influenced by human activities, are the most likely causes of observed Northern Hemisphere tropical expansion.

  12. Expansive or limitative strategy? A case study of organisational responses to new public health.

    PubMed

    Nielsen, Annegrete Juul; Knudsen, Morten; Finke, Katrine

    2008-01-01

    Since the emergence of new public health in the 1970s, health has not merely been considered the absence of disease, but physical, mental and social wellbeing. This article seeks to analyzes the implications of this broad concept of health at an organizational level. The paper presents a qualitative case study of boundary drawing in a Danish municipal agency in charge of planning and conducting health promoting and disease preventing activities from 1989 to 2005. The theoretical framework draws on Niklas Luhmann's organization theory. Two different organizational answers were found to the challenges inherent in the broad concept of new public health. First, the organization tried to increase its size and incorporate as many aspects of the environment as possible. This expansive strategy jeopardised the identity of the organization. Second, the organization tried to keep clear and tight boundaries and from this position irritate entities in the environment. This limitative strategy made the organization spend relatively more energy on organizing and controlling itself than on public health work. The case study shows how a broad concept of health makes boundary management topical in organizations dealing with health promotion and disease prevention. Organizations in charge of public health activities need to reflect on how they can create intelligent compensations for the disadvantages involved in an expansive or a limitative strategy. The broad concept of health inherent in new public health has been widely accepted and yet its challenges to organizational boundary drawing have attracted little attention. This paper provides an analysis of these challenges.

  13. "What took you so long?" The impact of PEPFAR on the expansion of HIV testing and counseling services in Africa.

    PubMed

    Marum, Elizabeth; Taegtmeyer, Miriam; Parekh, Bharat; Mugo, Nelly; Lembariti, Salama; Phiri, Mannasseh; Moore, Jan; Cheng, Alison S

    2012-08-15

    HIV testing and counseling services in Africa began in the early 1990s, with limited availability and coverage. Fears of stigma and discrimination, complex laboratory systems, and lack of available care and treatment services hampered expansion. Use of rapid point-of-care tests, introduction of services to prevent mother-to-child transmission, and increasing provision of antiretroviral drugs were key events in the late 1990s and early 2000s that facilitated the expansion of HIV testing and counseling services. Innovations in service delivery included providing HIV testing in both clinical and community sites, including mobile and home testing. Promotional campaigns were conducted in many countries, and evolutions in policies and guidance facilitated expansion and uptake. Support from President's Emergency Plan for AIDS Relief and national governments, other donors, and the Global Fund for AIDS, Tuberculosis, and Malaria contributed to significant increases in the numbers of persons tested in many countries. Quality of both testing and counseling, limited number of health care workers, uptake by couples, and effectiveness of linkages and referral systems remain challenges. Expansion of antiretroviral treatment, especially in light of the evidence that treatment contributes to prevention of transmission, will require greater yet strategic coverage of testing services, especially in clinical settings and in combination with other high-impact HIV prevention strategies. Continued support from President's Emergency Plan for AIDS Relief, governments, and other donors is required for the expansion of testing needed to achieve international targets for the scale-up of treatment and universal access to knowledge of HIV status.

  14. Medicaid Participation among Liver Transplant Candidates after the Affordable Care Act Medicaid Expansion.

    PubMed

    Tumin, Dmitry; Beal, Eliza W; Mumtaz, Khalid; Hayes, Don; Tobias, Joseph D; Pawlik, Timothy M; Washburn, W Kenneth; Black, Sylvester M

    2017-08-01

    The 2014 Medicaid expansion in participating states increased insurance coverage among people with chronic health conditions, but its implications for access to surgical care remain unclear. We investigated how Medicaid expansion influenced the insurance status of candidates for liver transplantation (LT) and transplant center payor mix. Data on LT candidates aged 18 to 64 years, in 2012 to 2013 (pre-expansion) and 2014 to 2015 (post-expansion), were obtained from the United Network for Organ Sharing registry. Change between the 2 periods in the percent of LT candidates using Medicaid was compared between expansion and nonexpansion states. Multivariable logistic regression was used to determine how Medicaid expansion influenced individual LT candidates' likelihood of using Medicaid insurance. The study included 33,017 LT candidates, of whom 29,666 had complete data for multivariable analysis. Medicaid enrollment increased by 4% after Medicaid expansion in participating states. One-quarter of the transplant centers in these states experienced ≥10% increase in the proportion of LT candidates using Medicaid insurance. Multivariable analysis confirmed that Medicaid expansion was associated with increased odds of LT candidates using Medicaid insurance (odds ratio 1.49; 95% CI 1.34, 1.66; p < 0.001). However, the absolute number and demographic characteristics of patients listed for LT did not change in Medicaid expansion states during the post-expansion period. Candidates for LT became more likely to use Medicaid after the 2014 Medicaid expansion policy came into effect. Enactment of this policy did not appear to increase access to LT or address socioeconomic and demographic disparities in access to the LT wait list. Copyright © 2017 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

  15. Continuum-wise expansiveness for generic diffeomorphisms

    NASA Astrophysics Data System (ADS)

    Lee, Manseob

    2018-06-01

    Let M be a closed smooth manifold and let be a diffeomorphism. C 1-generically, a continuum-wise expansive satisfies Axiom A without cycles. Let and let . There are a C 1 neighborhood of and a residual set such that for any , g is not continuum-wise expansive, where is the set of all robustly transitive diffeomorphisms on

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

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

    Paxton, William A.; Özdemir, Tevfik E.; Şavklıyıldız, İlyas

    Zirconiumore » m diboride (ZrB 2) is an attractive material due to its thermal and electrical properties. In recent years, ZrB 2has been investigated as a superior replacement for sapphire when used as a substrate for gallium nitride devices. Like sapphire, ZrB 2has an anisotropic hexagonal structure which defines its directionally dependent properties. However, the anisotropic behavior of ZrB 2is not well understood. In this paper, we use energy-dispersive synchrotron X-ray diffraction to measure the thermal expansion of polycrystalline ZrB 2powder from 300 to 1150 K. Nine Bragg reflections are fit using Pseudo-Voigt peak profiles and used to compute the a and c lattice parameters using a nonlinear least-squares approximation. The temperature-dependent instantaneous thermal expansion coefficients are determined for each a -axis and c -axis direction and are described by the following equations: α a = ( 4.1507 × 10 - 6 + 5.1086 × 10 - 9 ( T - 293.15 ) )/( 1 + 4.1507 × 10 - 6 ( T - 293.15 ) + 2.5543 × 10 - 9 ( T - 293.15 ) 2 ) and α c = ( 4.5374 × 10 - 6 + 4.3004 × 10 - 9 ( T - 293.15 ) )/( 1 + 4.5374 × 10 - 6 ( T - 293.15 ) + 2.1502 × 10 - 9 ( T - 293.15 ) 2 ). Our results are within range of previously reported values but describe the temperature anisotropy in more detail. We show that anisotropic expansion coefficients converge to the same value at about 780 K and diverge at higher temperatures. Results are compared with other reported values.« less

  17. Influence of fire on black-tailed prairie dog colony expansion in shortgrass steppe

    USGS Publications Warehouse

    Augustine, D.J.; Cully, J.F.; Johnson, T.L.

    2007-01-01

    Factors influencing the distribution and abundance of black-tailed prairie dog (Cynomys ludovicianus) colonies are of interest to rangeland managers because of the significant influence prairie dogs can exert on both livestock and biodiversity. We examined the influence of 4 prescribed burns and one wildfire on the rate and direction of prairie dog colony expansion in shortgrass steppe of southeastern Colorado. Our study was conducted during 2 years with below-average precipitation, when prairie dog colonies were expanding throughout the study area. Under these dry conditions, the rate of black-tailed prairie dog colony expansion into burned grassland (X?? = 2.6 ha??100-m perimeter-1??y-1; range = 0.8-5.9 ha??100-m perimeter-1??y-1; N = 5 colonies) was marginally greater than the expansion rate into unburned grassland (X?? =1.3 ha??100-m perimeter-1??y-1; range = 0.2-4.9 ha??100-m perimeter-1??y-1; N = 23 colonies; P = 0.066). For 3 colonies that were burned on only a portion of their perimeter, we documented consistently high rates of expansion into the adjacent burned grassland (38%-42% of available burned habitat colonized) but variable expansion rates into the adjacent unburned grassland (2%-39% of available unburned habitat colonized). While our results provide evidence that burning can increase colony expansion rate even under conditions of low vegetative structure, this effect was minor at the scale of the overall colony complex because some unburned colonies were also able to expand at high rates. This result highlights the need to evaluate effects of fire on colony expansion during above-average rainfall years, when expansion into unburned grassland may be considerably lower.

  18. 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…

  19. Rehabilitation of a Distressed Single Storied Building Founded on Expansive Soil: A Case Study

    NASA Astrophysics Data System (ADS)

    Pakrashi, Somdev

    2017-12-01

    A single storied building was constructed on strip foundation system—on a subsoil, with high expansivity, without taking necessary precautions and it suffered extensive cracks and damages in roof slab, beams, columns and brick walls, subsidence /upheavals in floors etc. within 2/3 years of its construction and consequently it had to be abandoned. The study examines the reasons for the severe damages, cracks etc. and also suggests remediation by ground improvement and other necessary measures that were actually taken up, to rehabilitate the highly distressed and abandoned building within a reasonably short period of time—at a reasonable cost.

  20. 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.

  1. 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...

  2. A Power Series Expansion and Its Applications

    ERIC Educational Resources Information Center

    Chen, Hongwei

    2006-01-01

    Using the power series solution of a differential equation and the computation of a parametric integral, two elementary proofs are given for the power series expansion of (arcsin x)[squared], as well as some applications of this expansion.

  3. An experimental investigation of wall boundary layer transition Reynolds numbers in an expansion tube

    NASA Technical Reports Server (NTRS)

    Weilmuenster, K. J.

    1974-01-01

    Experimental measurements of boundary-layer transition in an expansion-tube test-gas flow are presented along with radial distributions of pitot pressure. An integral method for calculating constant Reynolds number lines for an expansion-tube flow is introduced. Comparison of experimental data and constant Reynolds number calculations has shown that for given conditions, wall boundary-layer transition occurs at a constant Reynolds number in an expansion-tube flow. Operating conditions in the expansion tube were chosen so that the effects of test-gas nonequilibrium on boundary-layer transition could be studied.

  4. Expansion and Differentiation of Germline-Derived Pluripotent Stem Cells on Biomaterials

    PubMed Central

    Šarić, Tomo; Denecke, Bernd; Peinkofer, Gabriel; Bovi, Manfred; Groll, Jürgen; Ko, Kinarm; Salber, Jochen; Halbach, Marcel; Schöler, Hans R.; Zenke, Martin; Neuss, Sabine

    2013-01-01

    Stem cells with broad differentiation potential, such as the recently described germline-derived pluripotent stem cells (gPS cells), are an appealing source for tissue engineering strategies. Biomaterials can inhibit, support, or induce proliferation and differentiation of stem cells. Here we identified (1) polymers that maintain self-renewal and differentiation potential of gPS cells for feeder-free expansion and (2) polymers supporting the cardiomyogenic fate of gPS cells by analyzing a panel of polymers of an established biomaterial bank previously used to assess growth of diverse stem cell types. Identification of cytocompatible gPS cell/biomaterial combinations required analysis of several parameters, including morphology, viability, cytotoxicity, apoptosis, proliferation, and differentiation potential. Pluripotency of gPS cells was visualized by the endogenous Oct4-promoter-driven GFP and by Sox2 and Nanog immunofluorescence. Viability assay, proliferation assay, and flow cytometry showed that gPS cells efficiently adhere and are viable on synthetic polymers, such as Resomer® LR704 (poly(L-lactic-D,L-lactic acid), poly(tetrafluor ethylene) (PTFE), poly(vinylidene fluoride) (PVDF), and on gelatine-coated tissue culture polystyrene. Expansion experiments showed that Resomer LR704 is an alternative substrate for feeder-free gPS cell maintenance. Resomer LR704, PTFE, and PVDF were found to be suitable for gPS cell differentiation. Spontaneous beating in embryoid bodies cultured on Resomer LR704 occurred already on day 8 of differentiation, much earlier compared to the other surfaces. This indicates that Resomer LR704 supports spontaneous cardiomyogenic differentiation of gPS cells, which was also confirmed on molecular, protein and functional level. PMID:23234562

  5. Expansion and differentiation of germline-derived pluripotent stem cells on biomaterials.

    PubMed

    Hoss, Mareike; Šarić, Tomo; Denecke, Bernd; Peinkofer, Gabriel; Bovi, Manfred; Groll, Jürgen; Ko, Kinarm; Salber, Jochen; Halbach, Marcel; Schöler, Hans R; Zenke, Martin; Neuss, Sabine

    2013-05-01

    Stem cells with broad differentiation potential, such as the recently described germline-derived pluripotent stem cells (gPS cells), are an appealing source for tissue engineering strategies. Biomaterials can inhibit, support, or induce proliferation and differentiation of stem cells. Here we identified (1) polymers that maintain self-renewal and differentiation potential of gPS cells for feeder-free expansion and (2) polymers supporting the cardiomyogenic fate of gPS cells by analyzing a panel of polymers of an established biomaterial bank previously used to assess growth of diverse stem cell types. Identification of cytocompatible gPS cell/biomaterial combinations required analysis of several parameters, including morphology, viability, cytotoxicity, apoptosis, proliferation, and differentiation potential. Pluripotency of gPS cells was visualized by the endogenous Oct4-promoter-driven GFP and by Sox2 and Nanog immunofluorescence. Viability assay, proliferation assay, and flow cytometry showed that gPS cells efficiently adhere and are viable on synthetic polymers, such as Resomer(®) LR704 (poly(L-lactic-D,L-lactic acid), poly(tetrafluor ethylene) (PTFE), poly(vinylidene fluoride) (PVDF), and on gelatine-coated tissue culture polystyrene. Expansion experiments showed that Resomer LR704 is an alternative substrate for feeder-free gPS cell maintenance. Resomer LR704, PTFE, and PVDF were found to be suitable for gPS cell differentiation. Spontaneous beating in embryoid bodies cultured on Resomer LR704 occurred already on day 8 of differentiation, much earlier compared to the other surfaces. This indicates that Resomer LR704 supports spontaneous cardiomyogenic differentiation of gPS cells, which was also confirmed on molecular, protein and functional level.

  6. 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.

  7. Exploring the thermal expansion of fluorides and oxyfluorides with rhenium trioxide-type structures: From negative to positive thermal expansion

    NASA Astrophysics Data System (ADS)

    Greve, Benjamin K.

    This thesis explores the thermal expansion and high pressure behavior of some materials with the ReO3 structure type. This structure is simple and has, in principle, all of the features necessary for negative thermal expansion (NTE) arising from the transverse thermal motion of the bridging anions and the coupled rotation of rigid units; however, ReO 3 itself only exhibits mild NTE across a narrow temperature range at low temperatures. ReO3 is metallic because of a delocalized d-electron, and this may contribute to the lack of NTE in this material. The materials examined in this thesis are all based on d 0 metal ions so that the observed thermal expansion behavior should arise from vibrational, rather than electronic, effects. In Chapter 2, the thermal expansion of scandium fluoride, ScF3 , is examined using a combination of in situ synchrotron X-ray and neutron variable temperature diffraction. ScF3 retains the cubic ReO3 structure across the entire temperature range examined (10 - 1600 K) and exhibits pronounced negative thermal expansion at low temperatures. The magnitude of NTE in this material is comparable to that of cubic ZrW2O8, which is perhaps the most widely studied NTE material, at room temperature and below. This is the first report of NTE in an ReO3 type structure across a wide temperature range. Chapter 3 presents a comparison between titanium oxyfluoride, TiOF 2, and a vacancy-containing titanium hydroxyoxyfluoride, Ti x(O/OH/F)3. TiOF2 was originally reported to adopt the cubic ReO3 structure type under ambient conditions, therefore the initial goal for this study was to examine the thermal expansion of this material and determine if it displayed interesting behavior such as NTE. During the course of the study, it was discovered that the original synthetic method resulted in Tix(O/OH/F)3, which does adopt the cubic ReO3 structure type. The chemical composition of the hydroxyoxyfluoride is highly dependent upon synthesis conditions and subsequent

  8. Macro-Climatic Distribution Limits Show Both Niche Expansion and Niche Specialization among C4 Panicoids.

    PubMed

    Aagesen, Lone; Biganzoli, Fernando; Bena, Julia; Godoy-Bürki, Ana C; Reinheimer, Renata; Zuloaga, Fernando O

    2016-01-01

    Grasses are ancestrally tropical understory species whose current dominance in warm open habitats is linked to the evolution of C4 photosynthesis. C4 grasses maintain high rates of photosynthesis in warm and water stressed environments, and the syndrome is considered to induce niche shifts into these habitats while adaptation to cold ones may be compromised. Global biogeographic analyses of C4 grasses have, however, concentrated on diversity patterns, while paying little attention to distributional limits. Using phylogenetic contrast analyses, we compared macro-climatic distribution limits among ~1300 grasses from the subfamily Panicoideae, which includes 4/5 of the known photosynthetic transitions in grasses. We explored whether evolution of C4 photosynthesis correlates with niche expansions, niche changes, or stasis at subfamily level and within the two tribes Paniceae and Paspaleae. We compared the climatic extremes of growing season temperatures, aridity, and mean temperatures of the coldest months. We found support for all the known biogeographic distribution patterns of C4 species, these patterns were, however, formed both by niche expansion and niche changes. The only ubiquitous response to a change in the photosynthetic pathway within Panicoideae was a niche expansion of the C4 species into regions with higher growing season temperatures, but without a withdrawal from the inherited climate niche. Other patterns varied among the tribes, as macro-climatic niche evolution in the American tribe Paspaleae differed from the pattern supported in the globally distributed tribe Paniceae and at family level.

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

    NASA Astrophysics Data System (ADS)

    Samat, N.

    2014-02-01

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

  10. Differential cosmic expansion and the Hubble flow anisotropy

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

    Bolejko, Krzysztof; Nazer, M. Ahsan; Wiltshire, David L., E-mail: bolejko@physics.usyd.edu.au, E-mail: ahsan.nazer@canterbury.ac.nz, E-mail: david.wiltshire@canterbury.ac.nz

    2016-06-01

    The Universe on scales 10–100 h {sup −1}Mpc is dominated by a cosmic web of voids, filaments, sheets and knots of galaxy clusters. These structures participate differently in the global expansion of the Universe: from non-expanding clusters to the above average expansion rate of voids. In this paper we characterize Hubble expansion anisotropies in the COMPOSITE sample of 4534 galaxies and clusters. We concentrate on the dipole and quadrupole in the rest frame of the Local Group. These both have statistically significant amplitudes. These anisotropies, and their redshift dependence, cannot be explained solely by a boost of the Local Groupmore » in the Friedmann-Lemaitre-Robertson-Walker (FLRW) model which expands isotropically in the rest frame of the cosmic microwave background (CMB) radiation. We simulate the local expansion of the Universe with inhomogeneous Szekeres solutions, which match the standard FLRW model on ∼> 100 h {sup −1}Mpc scales but exhibit nonkinematic relativistic differential expansion on small scales. We restrict models to be consistent with observed CMB temperature anisotropies, while simultaneously fitting the redshift variation of the Hubble expansion dipole. We include features to account for both the Local Void and the 'Great Attractor'. While this naturally accounts for the Hubble expansion and CMB dipoles, the simulated quadrupoles are smaller than observed. Further refinement to incorporate additional structures may improve this. This would enable a test of the hypothesis that some large angle CMB anomalies result from failing to treat the relativistic differential expansion of the background geometry; a natural feature of solutions to Einstein's equations not included in the current standard model of cosmology.« less

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

    PubMed Central

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

    2014-01-01

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

  12. Average expansion rate and light propagation in a cosmological Tardis spacetime

    NASA Astrophysics Data System (ADS)

    Lavinto, Mikko; Räsänen, Syksy; Szybka, Sebastian J.

    2013-12-01

    We construct the first exact statistically homogeneous and isotropic cosmological solution in which inhomogeneity has a significant effect on the expansion rate. The universe is modelled as a Swiss Cheese, with dust FRW background and inhomogeneous holes. We show that if the holes are described by the quasispherical Szekeres solution, their average expansion rate is close to the background under certain rather general conditions. We specialise to spherically symmetric holes and violate one of these conditions. As a result, the average expansion rate at late times grows relative to the background, ie backreaction is significant. The holes fit smoothly into the background, but are larger on the inside than a corresponding background domain: we call them Tardis regions. We study light propagation, find the effective equations of state and consider the relation of the spatially averaged expansion rate to the redshift and the angular diameter distance.

  13. Giant Thermal Expansion in 2D and 3D Cellular Materials.

    PubMed

    Zhu, Hanxing; Fan, Tongxiang; Peng, Qing; Zhang, Di

    2018-05-01

    When temperature increases, the volume of an object changes. This property was quantified as the coefficient of thermal expansion only a few hundred years ago. Part of the reason is that the change of volume due to the variation of temperature is in general extremely small and imperceptible. Here, abnormal giant linear thermal expansions in different types of two-ingredient microstructured hierarchical and self-similar cellular materials are reported. The cellular materials can be 2D or 3D, and isotropic or anisotropic, with a positive or negative thermal expansion due to the convex or/and concave shape in their representative volume elements respectively. The magnitude of the thermal expansion coefficient can be several times larger than the highest value reported in the literature. This study suggests an innovative approach to develop temperature-sensitive functional materials and devices. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Spectral likelihood expansions for Bayesian inference

    NASA Astrophysics Data System (ADS)

    Nagel, Joseph B.; Sudret, Bruno

    2016-03-01

    A spectral approach to Bayesian inference is presented. It pursues the emulation of the posterior probability density. The starting point is a series expansion of the likelihood function in terms of orthogonal polynomials. From this spectral likelihood expansion all statistical quantities of interest can be calculated semi-analytically. The posterior is formally represented as the product of a reference density and a linear combination of polynomial basis functions. Both the model evidence and the posterior moments are related to the expansion coefficients. This formulation avoids Markov chain Monte Carlo simulation and allows one to make use of linear least squares instead. The pros and cons of spectral Bayesian inference are discussed and demonstrated on the basis of simple applications from classical statistics and inverse modeling.

  15. Origami structures for tunable thermal expansion

    NASA Astrophysics Data System (ADS)

    Boatti, Elisa; Bertoldi, Katia

    Materials with engineered thermal expansion, capable of achieving targeted and extreme area/volume changes in response to variations in temperature, are important for a number of aerospace, optical, energy, and microelectronic applications. While most of the proposed structures with tunable coefficient of thermal expansion consist of bi-material 2D or 3D lattices, here we propose a periodic metastructure based on a bilayer Miura-Ori origami fold. We combine experiments and simulations to demonstrate that by tuning the geometrical and mechanical parameters an extremely broad range of thermal expansion coefficients can be obtained, spanning both negative and positive values. Additionally, the thermal properties along different directions can be adjusted independently. Differently from all previously reported systems, the proposed structure is non-porous.

  16. The role of anisotropic expansion for pulmonary acinar aerosol deposition

    PubMed Central

    Hofemeier, Philipp; Sznitman, Josué

    2016-01-01

    Lung deformations at the local pulmonary acinar scale are intrinsically anisotropic. Despite progress in imaging modalities, the true heterogeneous nature of acinar expansion during breathing remains controversial, where our understanding of inhaled aerosol deposition still widely emanates from studies under self-similar, isotropic wall motions. Building on recent 3D models of multi-generation acinar networks, we explore in numerical simulations how different hypothesized scenarios of anisotropic expansion influence deposition outcomes of inhaled aerosols in the acinar depths. While the broader range of particles acknowledged to reach the acinar region (dp = 0.005–5.0 μm) are largely unaffected by the details of anisotropic expansion under tidal breathing, our results suggest nevertheless that anisotropy modulates the deposition sites and fractions for a narrow band of sub-micron particles (dp ~ 0.5–0.75 μm), where the fate of aerosols is greatly intertwined with local convective flows. Our findings underscore how intrinsic aerosol motion (i.e. diffusion, sedimentation) undermines the role of anisotropic wall expansion that is often attributed in determining aerosol mixing and acinar deposition. PMID:27614613

  17. Data availability and feasibility of various techniques to predict response to volume expansion in critically ill patients

    PubMed Central

    Lanspa, Michael J.; Briggs, Benjamin J.; Hirshberg, Eliotte L.; Pratt, Cristina M.; Grissom, Colin K.; Brown, Samuel M.

    2017-01-01

    Objective: The accuracy of various techniques to predict response to volume expansion in shock has been studied, but less well known is how feasible these techniques are in the ICU. Methods: This is a prospective observation single-center study of inpatients from a mixed profile ICU who received volume expansion. At time of volume expansion, we determined whether a particular technique to predict response was feasible, according to rules developed from available literature and nurse assessment. Results: We studied 214 volume expansions in 97 patients. The most feasible technique was central venous pressure (50%), followed by vena cava collapsibility, (47%) passive leg raise (42%), and stroke volume variation (22%). Aortic velocity variation, and pulse pressure variation, and were rarely feasible (1% each). In 37% of volume expansions, no technique that we assessed was feasible. Conclusions: Techniques to predict response to volume expansion are infeasible in many patients in shock. PMID:28971030

  18. Insurance Expansion and Hospital Emergency Department Access: Evidence From the Affordable Care Act.

    PubMed

    Garthwaite, Craig; Gross, Tal; Notowidigdo, Matthew; Graves, John A

    2017-02-07

    Little is known about whether insurance expansion affects the location and type of emergency department (ED) use. Understanding these changes can inform state-level decisions about the Medicaid expansion under the Patient Protection and Affordable Care Act (ACA). To investigate the effect of the 2014 ACA Medicaid expansion on the location, insurance status, and type of ED visits. Quasi-experimental observational study from 2012 to 2014. 126 investor-owned, hospital-based EDs. Uninsured and Medicaid-insured adults aged 18 to 64 years. ACA expansion of Medicaid in January 2014. Number of ED visits overall, type of visit (for example, nondiscretionary or nonemergency), and average travel time to the ED. Interrupted time-series analyses comparing changes from the end of 2013 to end of 2014 for patients from Medicaid expansion versus nonexpansion states were done. There were 1.06 million ED visits among patients from 17 Medicaid expansion states, and 7.87 million ED visits among patients from 19 nonexpansion states. The EDs treating patients from Medicaid expansion states saw an overall 47.1% decrease in uninsured visits (95% CI, -65.0% to -29.3%) and a 125.7% (CI, 89.2% to 162.6%) increase in Medicaid visits after 12 months of ACA expansion. Average travel time for nondiscretionary conditions requiring immediate medical care decreased by 0.9 minutes (-6.2% [CI, -8.9% to -3.5%]) among all Medicaid patients from expansion states. We found little evidence of similar changes among patients from nonexpansion states. Results reflect shifts in ED care at investor-owned facilities, which limits generalizability to other hospital types. Meaningful changes in insurance status and location and type of ED visits in the first year of ACA Medicaid expansion were found, suggesting that expansion provides patients with a greater choice of hospital facilities. Robert Wood Johnson Foundation.

  19. The analytic structure of non-global logarithms: Convergence of the dressed gluon expansion

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

    Larkoski, Andrew J.; Moult, Ian; Neill, Duff Austin

    Non-global logarithms (NGLs) are the leading manifestation of correlations between distinct phase space regions in QCD and gauge theories and have proven a challenge to understand using traditional resummation techniques. Recently, the dressed gluon ex-pansion was introduced that enables an expansion of the NGL series in terms of a “dressed gluon” building block, defined by an all-orders factorization theorem. Here, we clarify the nature of the dressed gluon expansion, and prove that it has an infinite radius of convergence as a solution to the leading logarithmic and large-N c master equation for NGLs, the Banfi-Marchesini-Smye (BMS) equation. The dressed gluonmore » expansion therefore provides an expansion of the NGL series that can be truncated at any order, with reliable uncertainty estimates. In contrast, manifest in the results of the fixed-order expansion of the BMS equation up to 12-loops is a breakdown of convergence at a finite value of α slog. We explain this finite radius of convergence using the dressed gluon expansion, showing how the dynamics of the buffer region, a region of phase space near the boundary of the jet that was identified in early studies of NGLs, leads to large contributions to the fixed order expansion. We also use the dressed gluon expansion to discuss the convergence of the next-to-leading NGL series, and the role of collinear logarithms that appear at this order. Finally, we show how an understanding of the analytic behavior obtained from the dressed gluon expansion allows us to improve the fixed order NGL series using conformal transformations to extend the domain of analyticity. Furthermore, this allows us to calculate the NGL distribution for all values of α slog from the coefficients of the fixed order expansion.« less

  20. The analytic structure of non-global logarithms: Convergence of the dressed gluon expansion

    DOE PAGES

    Larkoski, Andrew J.; Moult, Ian; Neill, Duff Austin

    2016-11-15

    Non-global logarithms (NGLs) are the leading manifestation of correlations between distinct phase space regions in QCD and gauge theories and have proven a challenge to understand using traditional resummation techniques. Recently, the dressed gluon ex-pansion was introduced that enables an expansion of the NGL series in terms of a “dressed gluon” building block, defined by an all-orders factorization theorem. Here, we clarify the nature of the dressed gluon expansion, and prove that it has an infinite radius of convergence as a solution to the leading logarithmic and large-N c master equation for NGLs, the Banfi-Marchesini-Smye (BMS) equation. The dressed gluonmore » expansion therefore provides an expansion of the NGL series that can be truncated at any order, with reliable uncertainty estimates. In contrast, manifest in the results of the fixed-order expansion of the BMS equation up to 12-loops is a breakdown of convergence at a finite value of α slog. We explain this finite radius of convergence using the dressed gluon expansion, showing how the dynamics of the buffer region, a region of phase space near the boundary of the jet that was identified in early studies of NGLs, leads to large contributions to the fixed order expansion. We also use the dressed gluon expansion to discuss the convergence of the next-to-leading NGL series, and the role of collinear logarithms that appear at this order. Finally, we show how an understanding of the analytic behavior obtained from the dressed gluon expansion allows us to improve the fixed order NGL series using conformal transformations to extend the domain of analyticity. Furthermore, this allows us to calculate the NGL distribution for all values of α slog from the coefficients of the fixed order expansion.« less

  1. How will oil palm expansion affect biodiversity?

    PubMed

    Fitzherbert, Emily B; Struebig, Matthew J; Morel, Alexandra; Danielsen, Finn; Brühl, Carsten A; Donald, Paul F; Phalan, Ben

    2008-10-01

    Oil palm is one of the world's most rapidly increasing crops. We assess its contribution to tropical deforestation and review its biodiversity value. Oil palm has replaced large areas of forest in Southeast Asia, but land-cover change statistics alone do not allow an assessment of where it has driven forest clearance and where it has simply followed it. Oil palm plantations support much fewer species than do forests and often also fewer than other tree crops. Further negative impacts include habitat fragmentation and pollution, including greenhouse gas emissions. With rising demand for vegetable oils and biofuels, and strong overlap between areas suitable for oil palm and those of most importance for biodiversity, substantial biodiversity losses will only be averted if future oil palm expansion is managed to avoid deforestation.

  2. The { β}-expansion formalism in perturbative QCD and its extension

    NASA Astrophysics Data System (ADS)

    Kataev, A. L.; Mikhailov, S. V.

    2016-11-01

    We discuss the { β}-expansion for renormalization group invariant quantities tracing this expansion to the different contractions of the corresponding incomplete BPHZ R-operation. All of the coupling renormalizations, which follow from these contractions, should be taken into account for the { β}-expansion. We illustrate this feature considering the nonsinglet Adler function D NS in the third order of perturbation. We propose a generalization of the { β}-expansion for the renormalization group covariant quantities — the { β, γ}-expansion.

  3. Thermal Expansion of Vitrified Blood Vessels Permeated with DP6 and Synthetic Ice Modulators

    PubMed Central

    Eisenberg, David P.; Taylor, Michael J.; Jimenez-Rios, Jorge L.; Rabin, Yoed

    2014-01-01

    This study provides thermal expansion data for blood vessels permeated with the cryoprotective cocktail DP6, when combined with selected synthetic ice modulators (SIMs): 12% polyethylene glycol 400, 6% 1,3-cyclohexanediol, and 6% 2,3-butanediol. The general classification of SIMs includes molecules that modulate ice nucleation and growth, or possess properties of stabilizing the amorphous state, by virtue of their chemical structure and at concentrations that are not explained on a purely colligative basis. The current study is part of an ongoing effort to characterize thermo-mechanical effects on structural integrity of cryopreserved materials, where thermal expansion is the driving mechanism to thermo-mechanical stress. This study focuses on the lower part of the cryogenic temperature range, where the cryoprotective agent (CPA) behaves as a solid for all practical applications. By combining results obtained in the current study with literature data on the thermal expansion in the upper part of the cryogenic temperature range, unified thermal expansion curves are presented. PMID:24769313

  4. 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

    ... 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, the Agency for Healthcare Research and Quality (AHRQ) informs the public of an...

  5. [Clinical effect of removable lingual arch plus auxiliary spring for dental arch expansion].

    PubMed

    Sun, Feng-yang; Zhang, Yu

    2007-04-01

    Observe the clinical effect of removable lingual arch plus auxiliary spring for convenient dental (especially mandibular) arch expansion. Seventeen patients with dental arch constriction complicated by mild dental crowding were enrolled in this study, including 9 requiring maxillary arch expansion and 8 necessitating mandibular expansion. The patients were divided to two groups at random for arch expansion with removable lingual arch plus auxiliary spring and with Quad-helix, respectively, and the effect of arch expansion was compared between the two groups. After 8 weeks of arch expansion, the average width of U4-U4 and U5-U5 in removable lingual arch group was enlarged by 2.2 mm and 3.0 mm, and that in Quad-helix group by 2.3 mm and 3.5 mm, respectively, showing no significant differences between the two groups (P>0.05). After 12 weeks of treatment, the average width of L4-L4 and L5-L5 in the former group was enlarged by 2.3 mm and 2.5 mm, respectively, significantly greater than that in the latter group (1.0 mm and 1.2 mm, P<0.05). Removable lingual arch plus auxiliary spring allows significant expansion of the middle segment of the dental arch (bicuspids), and can be more effective than Quad-helix for mandibular arch expansion.

  6. 49 CFR 179.220-16 - Expansion capacity.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) SPECIFICATIONS FOR TANK CARS Specifications for Non-Pressure Tank Car Tanks (Classes DOT-111AW and 115AW) § 179.220-16 Expansion capacity. Expansion capacity...

  7. An Analysis of Educational Inequality in Taiwan after the Higher Education Expansion

    ERIC Educational Resources Information Center

    Lin, Chun-Hung A.; Yang, Chih-Hai

    2009-01-01

    Two major educational expansions in Taiwan have resulted in a remarkable improvement of human capital accumulation for the last three decades, which is consistent with the long-run goal of education in improving individual well-being and international competitiveness. This study focuses on the expansion of higher education starting from the late…

  8. Anisotropic expansion of Pu through the α-β-γ phase transitions while under radial compressive stress

    NASA Astrophysics Data System (ADS)

    Spearing, Dane R.; Veirs, D. Kirk; Prenger, F. Coyne

    2000-07-01

    In support of the new US Department of Energy (DOE) standard for the stabilization, packaging, and storage of plutonium bearing materials, the effects of the volume expansion associated with the α/β and β/γ transformations of Pu metal on the integrity of a stainless steel storage container were examined.

  9. C9ORF72 Repeat Expansion in Australian and Spanish Frontotemporal Dementia Patients

    PubMed Central

    Dobson-Stone, Carol; Hallupp, Marianne; Loy, Clement T.; Thompson, Elizabeth M.; Haan, Eric; Sue, Carolyn M.; Panegyres, Peter K.; Razquin, Cristina; Seijo-Martínez, Manuel; Rene, Ramon; Gascon, Jordi; Campdelacreu, Jaume; Schmoll, Birgit; Volk, Alexander E.; Brooks, William S.; Schofield, Peter R.; Pastor, Pau; Kwok, John B. J.

    2013-01-01

    A hexanucleotide repeat expansion in C9ORF72 has been established as a common cause of frontotemporal dementia (FTD). However, the minimum repeat number necessary for disease pathogenesis is not known. The aims of our study were to determine the frequency of the C9ORF72 repeat expansion in two FTD patient collections (one Australian and one Spanish, combined n = 190), to examine C9ORF72 expansion allele length in a subset of FTD patients, and to examine C9ORF72 allele length in ‘non-expansion’ patients (those with <30 repeats). The C9ORF72 repeat expansion was detected in 5–17% of patients (21–41% of familial FTD patients). For one family, the expansion was present in the proband but absent in the mother, who was diagnosed with dementia at age 68. No association was found between C9ORF72 non-expanded allele length and age of onset and in the Spanish sample mean allele length was shorter in cases than in controls. Southern blotting analysis revealed that one of the nine ‘expansion-positive’ patients examined, who had neuropathologically confirmed frontotemporal lobar degeneration with TDP-43 pathology, harboured an ‘intermediate’ allele with a mean size of only ∼65 repeats. Our study indicates that the C9ORF72 repeat expansion accounts for a significant proportion of Australian and Spanish FTD cases. However, C9ORF72 allele length does not influence the age at onset of ‘non-expansion’ FTD patients in the series examined. Expansion of the C9ORF72 allele to as little as ∼65 repeats may be sufficient to cause disease. PMID:23437264

  10. Experimental residual stress evaluation of hydraulic expansion transitions in Alloy 690 steam generator tubing

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

    McGregor, R.; Doherty, P.; Hornbach, D.

    1995-12-31

    Nuclear Steam Generator (SG) service reliability and longevity have been seriously affected worldwide by corrosion at the tube-to-tubesheet joint expansion. Current SG designs for new facilities and replacement projects enhance corrosion resistance through the use of advanced tubing materials and improved joint design and fabrication techniques. Here, transition zones of hydraulic expansions have undergone detailed experimental evaluation to define residual stress and cold-work distribution on and below the secondary-side surface. Using X-ray diffraction techniques, with supporting finite element analysis, variations are compared in tubing metallurgical condition, tube/pitch geometry, expansion pressure, and tube-to-hole clearance. Initial measurements to characterize the unexpanded tubemore » reveal compressive stresses associated with a thin work-hardened layer on the outer surface of the tube. The gradient of cold-work was measured as 3% to 0% within .001 inch of the surface. The levels and character of residual stresses following hydraulic expansion are primarily dependent on this work-hardened surface layer and initial stress state that is unique to each tube fabrication process. Tensile stresses following expansion are less than 25% of the local yield stress and are found on the transition in a narrow circumferential band at the immediate tube surface (< .0002 inch/0.005 mm depth). The measurements otherwise indicate a predominance of compressive stresses on and below the secondary-side surface of the transition zone. Excellent resistance to SWSCC initiation is offered by the low levels of tensile stress and cold-work. Propagation of any possible cracking would be deterred by the compressive stress field that surrounds this small volume of tensile material.« less

  11. Energy Absorption of Expansion Tube Considering Local Buckling Characteristics

    NASA Astrophysics Data System (ADS)

    Ahn, Kwang-Hyun; Kim, Jin-Sung; Huh, Hoon

    This paper deals with the crash energy absorption and the local buckling characteristics of the expansion tube during the tube expanding processes. In order to improve energy absorption capacity of expansion tubes, local buckling characteristics of an expansion tube must be considered. The local buckling load and the absorbed energy during the expanding process were calculated for various types of tubes and punch shapes with finite element analysis. The energy absorption capacity of the expansion tube is influenced by the tube and the punch shape. The material properties of tubes are also important parameter for energy absorption. During the expanding process, local buckling occurs in some cases, which causes significant decreasing the absorbed energy of the expansion tube. Therefore, it is important to predict the local buckling load accurately to improve the energy absorption capacity of the expansion tube. Local buckling takes place relatively easily at the large punch angle and expansion ratio. Local buckling load is also influenced by both the tube radius and the thickness. In prediction of the local buckling load, modified Plantema equation was used for strain hardening and strain rate hardening. The modified Plantema equation shows a good agreement with the numerical result.

  12. Expansion and Harvesting of hMSC-TERT

    PubMed Central

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

    2007-01-01

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

  13. Local expansion flows of galaxies: quantifying acceleration effect of dark energy

    NASA Astrophysics Data System (ADS)

    Chernin, A. D.; Teerikorpi, P.

    2013-08-01

    The nearest expansion flow of galaxies observed around the Local group is studied as an archetypical example of the newly discovered local expansion flows around groups and clusters of galaxies in the nearby Universe. The flow is accelerating due to the antigravity produced by the universal dark energy background. We introduce a new acceleration measure of the flow which is the dimensionless ``acceleration parameter" Q (x) = x - x-2 depending on the normalized distance x only. The parameter is zero at the zero-gravity distance x = 1, and Q(x) ∝ x, when x ≫ 1. At the distance x = 3, the parameter Q = 2.9. Since the expansion flows have a self-similar structure in normalized variables, we expect that the result is valid as well for all the other expansion flows around groups and clusters of galaxies on the spatial scales from ˜ 1 to ˜ 10 Mpc everywhere in the Universe.

  14. Multiple Inflammatory Cytokines Converge to Regulate CD8+ T cell Expansion and Function During Tuberculosis

    PubMed Central

    Booty, Matthew G.; Nunes-Alves, Cláudio; Carpenter, Stephen M.; Jayaraman, Pushpa; Behar, Samuel M.

    2015-01-01

    The differentiation of effector CD8+ T cells is a dynamically regulated process that varies during different infections and is influenced by the inflammatory milieu of the host. Here, we define three signals regulating CD8+ T cell responses during tuberculosis by focusing on cytokines known to affect disease outcome: IL-12, type I IFN, and IL-27. Using mixed bone marrow chimeras, we compared wild type and cytokine receptor knockout CD8+ T cells within the same mouse following aerosol infection with Mycobacterium tuberculosis. Four weeks post-infection, IL-12, type 1 IFN, and IL-27 were all required for efficient CD8+ T cell expansion in the lungs. We next determined if these cytokines directly promote CD8+ T cell priming or are required only for expansion in the lungs. Utilizing retrogenic CD8+ T cells specific for the Mtb antigen TB10.4 (EsxH), we observed that IL-12 is the dominant cytokine driving both CD8+ T cell priming in the lymph node and expansion in the lungs; however, type I IFN and IL-27 have non-redundant roles supporting pulmonary CD8+ T cell expansion. Thus, IL-12 is a major signal promoting priming in the lymph node, but a multitude of inflammatory signals converge in the lung to promote continued expansion. Furthermore, these cytokines regulate the differentiation and function of CD8+ T cells during tuberculosis. These data demonstrate distinct and overlapping roles for each of the cytokines examined and underscore the complexity of CD8+ T cell regulation during tuberculosis. PMID:26755819

  15. The mechanics of surface expansion anisotropy in Medicago truncatula root hairs.

    PubMed

    Dumais, Jacques; Long, Sharon R; Shaw, Sidney L

    2004-10-01

    Wall expansion in tip-growing cells shows variations according to position and direction. In Medicago truncatula root hairs, wall expansion exhibits a strong meridional gradient with a maximum near the pole of the cell. Root hair cells also show a striking expansion anisotropy, i.e. over most of the dome surface the rate of circumferential wall expansion exceeds the rate of meridional expansion. Concomitant measurements of expansion rates and wall stresses reveal that the extensibility of the cell wall must vary abruptly along the meridian of the cell to maintain the gradient of wall expansion. To determine the mechanical basis of expansion anisotropy, we compared measurements of wall expansion with expansion patterns predicted from wall structural models that were either fully isotropic, transversely isotropic, or fully anisotropic. Our results indicate that a model based on a transversely isotropic wall structure can provide a good fit of the data although a fully anisotropic model offers the best fit overall. We discuss how such mechanical properties could be controlled at the microstructural level.

  16. Can Distance Education Increase Educational Equality? Evidence from the Expansion of Chinese Higher Education

    ERIC Educational Resources Information Center

    Li, Fengliang; Zhou, Mengying; Fan, Baolong

    2014-01-01

    Since China decided to expand its higher education, we have seen an increasing number of discussions of the relationship between educational expansion and equality. However, few studies have examined whether the expansion of distance higher education will improve educational equality among different regions. In this study, we analyzed the changes…

  17. Population expansions dominate demographic histories of endemic and widespread Pacific reef fishes.

    PubMed

    Delrieu-Trottin, Erwan; Mona, Stefano; Maynard, Jeffrey; Neglia, Valentina; Veuille, Michel; Planes, Serge

    2017-01-16

    Despite the unique nature of endemic species, their origin and population history remain poorly studied. We investigated the population history of 28 coral reef fish species, close related, from the Gambier and Marquesas Islands, from five families, with range size varying from widespread to small-range endemic. We analyzed both mitochondrial and nuclear sequence data using neutrality test and Bayesian analysis (EBSP and ABC). We found evidence for demographic expansions for most species (24 of 28), irrespective of range size, reproduction strategy or archipelago. The timing of the expansions varied greatly among species, from 8,000 to 2,000,000 years ago. The typical hypothesis for reef fish that links population expansions to the Last Glacial Maximum fit for 14 of the 24 demographic expansions. We propose two evolutionary processes that could lead to expansions older than the LGM: (a) we are retrieving the signature of an old colonization process for widespread, large-range endemic and paleoendemic species or (b) speciation; the expansion reflects the birth of the species for neoendemic species. We show for the first time that the demographic histories of endemic and widespread reef fish are not distinctly different and suggest that a number of processes drive endemism.

  18. Expansion/Facemask Treatment of an Adult Class III Malocclusion.

    PubMed

    Jackson, Gregory W; Kravitz, Neal D

    2014-01-01

    The orthodontic treatment of class III malocclusion with a maxillary deficiency is often treated with maxillary protraction with or without expansion. Skeletal and dental changes have been documented which have combined for the protraction of the maxilla and the correction of the class III malocclusion. Concerning the ideal time to treat a developing class III malocclusion, studies have reported that, although early treatment may be the most effective, face mask therapy can provide a viable option for older children as well. But what about young adults? Can the skeletal and dental changes seen in expansion/facemask therapy in children and adolescents be demonstrated in this age group as well, possibly eliminating the need for orthodontic dental camouflage treatment or orthognathic surgery? A case report is presented of an adult class III malocclusion with a Class III skeletal pattern and maxillary retrusion. Treatment was with nonextraction, comprehensive edgewise mechanics with slow maxillary expansion with a bonded expander and protraction facemask.

  19. 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

  20. Comparison among Magnus/Floquet/Fer expansion schemes in solid-state NMR.

    PubMed

    Takegoshi, K; Miyazawa, Norihiro; Sharma, Kshama; Madhu, P K

    2015-04-07

    We here revisit expansion schemes used in nuclear magnetic resonance (NMR) for the calculation of effective Hamiltonians and propagators, namely, Magnus, Floquet, and Fer expansions. While all the expansion schemes are powerful methods there are subtle differences among them. To understand the differences, we performed explicit calculation for heteronuclear dipolar decoupling, cross-polarization, and rotary-resonance experiments in solid-state NMR. As the propagator from the Fer expansion takes the form of a product of sub-propagators, it enables us to appreciate effects of time-evolution under Hamiltonians with different orders separately. While 0th-order average Hamiltonian is the same for the three expansion schemes with the three cases examined, there is a case that the 2nd-order term for the Magnus/Floquet expansion is different from that obtained with the Fer expansion. The difference arises due to the separation of the 0th-order term in the Fer expansion. The separation enables us to appreciate time-evolution under the 0th-order average Hamiltonian, however, for that purpose, we use a so-called left-running Fer expansion. Comparison between the left-running Fer expansion and the Magnus expansion indicates that the sign of the odd orders in Magnus may better be reversed if one would like to consider its effect in order.

  1. Comparison among Magnus/Floquet/Fer expansion schemes in solid-state NMR

    NASA Astrophysics Data System (ADS)

    Takegoshi, K.; Miyazawa, Norihiro; Sharma, Kshama; Madhu, P. K.

    2015-04-01

    We here revisit expansion schemes used in nuclear magnetic resonance (NMR) for the calculation of effective Hamiltonians and propagators, namely, Magnus, Floquet, and Fer expansions. While all the expansion schemes are powerful methods there are subtle differences among them. To understand the differences, we performed explicit calculation for heteronuclear dipolar decoupling, cross-polarization, and rotary-resonance experiments in solid-state NMR. As the propagator from the Fer expansion takes the form of a product of sub-propagators, it enables us to appreciate effects of time-evolution under Hamiltonians with different orders separately. While 0th-order average Hamiltonian is the same for the three expansion schemes with the three cases examined, there is a case that the 2nd-order term for the Magnus/Floquet expansion is different from that obtained with the Fer expansion. The difference arises due to the separation of the 0th-order term in the Fer expansion. The separation enables us to appreciate time-evolution under the 0th-order average Hamiltonian, however, for that purpose, we use a so-called left-running Fer expansion. Comparison between the left-running Fer expansion and the Magnus expansion indicates that the sign of the odd orders in Magnus may better be reversed if one would like to consider its effect in order.

  2. Expansive Cements

    DTIC Science & Technology

    1970-10-01

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

  3. A strictly Markovian expansion for plasma turbulence theory

    NASA Technical Reports Server (NTRS)

    Jones, F. C.

    1976-01-01

    The collision operator that appears in the equation of motion for a particle distribution function that was averaged over an ensemble of random Hamiltonians is non-Markovian. It is non-Markovian in that it involves a propagated integral over the past history of the ensemble averaged distribution function. All formal expansions of this nonlinear collision operator to date preserve this non-Markovian character term by term yielding an integro-differential equation that must be converted to a diffusion equation by an additional approximation. An expansion is derived for the collision operator that is strictly Markovian to any finite order and yields a diffusion equation as the lowest nontrivial order. The validity of this expansion is seen to be the same as that of the standard quasilinear expansion.

  4. 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...

  5. Future urban land expansion and implications for global croplands.

    PubMed

    Bren d'Amour, Christopher; Reitsma, Femke; Baiocchi, Giovanni; Barthel, Stephan; Güneralp, Burak; Erb, Karl-Heinz; Haberl, Helmut; Creutzig, Felix; Seto, Karen C

    2017-08-22

    Urban expansion often occurs on croplands. However, there is little scientific understanding of how global patterns of future urban expansion will affect the world's cultivated areas. Here, we combine spatially explicit projections of urban expansion with datasets on global croplands and crop yields. Our results show that urban expansion will result in a 1.8-2.4% loss of global croplands by 2030, with substantial regional disparities. About 80% of global cropland loss from urban expansion will take place in Asia and Africa. In both Asia and Africa, much of the cropland that will be lost is more than twice as productive as national averages. Asia will experience the highest absolute loss in cropland, whereas African countries will experience the highest percentage loss of cropland. Globally, the croplands that are likely to be lost were responsible for 3-4% of worldwide crop production in 2000. Urban expansion is expected to take place on cropland that is 1.77 times more productive than the global average. The loss of cropland is likely to be accompanied by other sustainability risks and threatens livelihoods, with diverging characteristics for different megaurban regions. Governance of urban area expansion thus emerges as a key area for securing livelihoods in the agrarian economies of the Global South.

  6. Future urban land expansion and implications for global croplands

    PubMed Central

    Bren d’Amour, Christopher; Reitsma, Femke; Baiocchi, Giovanni; Barthel, Stephan; Güneralp, Burak; Erb, Karl-Heinz; Haberl, Helmut; Seto, Karen C.

    2017-01-01

    Urban expansion often occurs on croplands. However, there is little scientific understanding of how global patterns of future urban expansion will affect the world’s cultivated areas. Here, we combine spatially explicit projections of urban expansion with datasets on global croplands and crop yields. Our results show that urban expansion will result in a 1.8–2.4% loss of global croplands by 2030, with substantial regional disparities. About 80% of global cropland loss from urban expansion will take place in Asia and Africa. In both Asia and Africa, much of the cropland that will be lost is more than twice as productive as national averages. Asia will experience the highest absolute loss in cropland, whereas African countries will experience the highest percentage loss of cropland. Globally, the croplands that are likely to be lost were responsible for 3–4% of worldwide crop production in 2000. Urban expansion is expected to take place on cropland that is 1.77 times more productive than the global average. The loss of cropland is likely to be accompanied by other sustainability risks and threatens livelihoods, with diverging characteristics for different megaurban regions. Governance of urban area expansion thus emerges as a key area for securing livelihoods in the agrarian economies of the Global South. PMID:28028219

  7. Evolution of density-dependent movement during experimental range expansions.

    PubMed

    Fronhofer, E A; Gut, S; Altermatt, F

    2017-12-01

    Range expansions and biological invasions are prime examples of transient processes that are likely impacted by rapid evolutionary changes. As a spatial process, range expansions are driven by dispersal and movement behaviour. Although it is widely accepted that dispersal and movement may be context-dependent, for instance density-dependent, and best represented by reaction norms, the evolution of density-dependent movement during range expansions has received little experimental attention. We therefore tested current theory predicting the evolution of increased movement at low densities at range margins using highly replicated and controlled range expansion experiments across multiple genotypes of the protist model system Tetrahymena thermophila. Although rare, we found evolutionary changes during range expansions even in the absence of initial standing genetic variation. Range expansions led to the evolution of negatively density-dependent movement at range margins. In addition, we report the evolution of increased intrastrain competitive ability and concurrently decreased population growth rates in range cores. Our findings highlight the importance of understanding movement and dispersal as evolving reaction norms and plastic life-history traits of central relevance for range expansions, biological invasions and the dynamics of spatially structured systems in general. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

  8. Co-Creating an Expansive Health Care Learning System.

    PubMed

    Cribb, Alan; Owens, John; Singh, Guddi

    2017-11-01

    How should practices of co-creation be integrated into health professions education? Although co-creation permits a variety of interpretations, we argue that realizing a transformative vision of co-creation-one that invites professionals to genuinely reconsider the purposes, relationships, norms, and priorities of health care systems through new forms of collaborative thought and practice-will require radically rethinking existing approaches to professional education. The meaningful enactment of co-creative roles and practices requires health professionals and students to negotiate competing traditions, pressures, and expectations. We therefore suggest that the development of what we call an "expansive health care learning system" is crucial for supporting learners in meeting the challenges of establishing genuinely co-creative health care systems. © 2017 American Medical Association. All Rights Reserved.

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

    PubMed Central

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

    2013-01-01

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

  10. Hoberman-sphere-inspired lattice metamaterials with tunable negative thermal expansion

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

    Li, Yangbo; Chen, Yanyu; Li, Tiantian

    Materials with engineered thermal expansion coefficients, capable of avoiding failure or irreversible destruction of structures and devices, are important for aerospace, civil, biomedical, optics, and semiconductor applications. In natural materials, thermal expansion usually cannot be adjusted easily and a negative thermal expansion coefficient is still uncommon. Here we propose a novel architected lattice bi-material system, inspired by the Hoberman sphere, showing a wide range of tunable thermal expansion coefficient from negative to positive, -1.04 x 10 -3 degrees C-1 to 1.0 x 10 -5 degrees C-1. Numerical simulations and analytical formulations are implemented to quantify the evolution of the thermalmore » expansion coefficients and reveal the underlying mechanisms responsible for this unusual behavior. We show that the thermal expansion coefficient of the proposed metamaterials depends on the thermal expansion coefficient ratio and the axial stiffness ratio of the constituent materials, as well as the bending stiffness and the topological arrangement of the constitutive elements. The finding reported here provides a new routine to design architected metamaterial systems with tunable negative thermal expansion for a wide range of potential applications.« less

  11. Hoberman-sphere-inspired lattice metamaterials with tunable negative thermal expansion

    DOE PAGES

    Li, Yangbo; Chen, Yanyu; Li, Tiantian; ...

    2018-02-02

    Materials with engineered thermal expansion coefficients, capable of avoiding failure or irreversible destruction of structures and devices, are important for aerospace, civil, biomedical, optics, and semiconductor applications. In natural materials, thermal expansion usually cannot be adjusted easily and a negative thermal expansion coefficient is still uncommon. Here we propose a novel architected lattice bi-material system, inspired by the Hoberman sphere, showing a wide range of tunable thermal expansion coefficient from negative to positive, -1.04 x 10 -3 degrees C-1 to 1.0 x 10 -5 degrees C-1. Numerical simulations and analytical formulations are implemented to quantify the evolution of the thermalmore » expansion coefficients and reveal the underlying mechanisms responsible for this unusual behavior. We show that the thermal expansion coefficient of the proposed metamaterials depends on the thermal expansion coefficient ratio and the axial stiffness ratio of the constituent materials, as well as the bending stiffness and the topological arrangement of the constitutive elements. The finding reported here provides a new routine to design architected metamaterial systems with tunable negative thermal expansion for a wide range of potential applications.« less

  12. Thermal expansion in the nickel-chromium-aluminum and cobalt-chromium-aluminum systems to 1200 degrees C

    NASA Technical Reports Server (NTRS)

    Lowell, C. E.; Garlick, R. G.; Henry, B.

    1975-01-01

    Thermal expansion data were obtained on 12 Ni-Cr-Al and 9 Co-Cr-Al alloys by high temperature X-ray diffraction. The data were computer fit to an empirical thermal expansion equation developed in the study. It is shown that the fit is excellent to good, and that the expansion constants depend on phase but not on composition. Phases for the Ni-Cr-Al system and Co-Cr-Al system are given. Results indicate that only alpha Cr has an expansion constant low enough to minimize oxide spalling or coating cracking induced by thermal expansion mismatch.

  13. 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)

  14. Hematopoietic Stem Cells: Transcriptional Regulation, Ex Vivo Expansion and Clinical Application

    PubMed Central

    Aggarwal, R.; Lu, J.; Pompili, V.J.; Das, H.

    2012-01-01

    Maintenance of ex vivo hematopoietic stem cells (HSC) pool and its differentiated progeny is regulated by complex network of transcriptional factors, cell cycle proteins, extracellular matrix, and their microenvironment through an orchestrated fashion. Strides have been made to understand the mechanisms regulating in vivo quiescence and proliferation of HSCs to develop strategies for ex vivo expansion. Ex vivo expansion of HSCs is important to procure sufficient number of stem cells and as easily available source for HSC transplants for patients suffering from hematological disorders and malignancies. Our lab has established a nanofiber-based ex vivo expansion strategy for HSCs, while preserving their stem cell characteristics. Ex vivo expanded cells were also found biologically functional in various disease models. However, the therapeutic potential of expanded stem cells at clinical level still needs to be verified. This review outlines transcriptional factors that regulate development of HSCs and their commitment, genes that regulate cell cycle status, studies that attempt to develop an effective and efficient protocol for ex vivo expansion of HSCs and application of HSC in various non-malignant and malignant disorders. Overall the goal of the current review is to deliver an understanding of factors that are critical in resolving the challenges that limit the expansion of HSCs in vivo and ex vivo. PMID:22082480

  15. Porous composite with negative thermal expansion obtained by photopolymer additive manufacturing

    NASA Astrophysics Data System (ADS)

    Takezawa, Akihiro; Kobashi, Makoto; Kitamura, Mitsuru

    2015-07-01

    Additive manufacturing (AM) could be a novel method of fabricating composite and porous materials having various effective performances based on mechanisms of their internal geometries. Materials fabricated by AM could rapidly be used in industrial application since they could easily be embedded in the target part employing the same AM process used for the bulk material. Furthermore, multi-material AM has greater potential than usual single-material AM in producing materials with effective properties. Negative thermal expansion is a representative effective material property realized by designing a composite made of two materials with different coefficients of thermal expansion. In this study, we developed a porous composite having planar negative thermal expansion by employing multi-material photopolymer AM. After measurement of the physical properties of bulk photopolymers, the internal geometry was designed by topology optimization, which is the most effective structural optimization in terms of both minimizing thermal stress and maximizing stiffness. The designed structure was converted to a three-dimensional stereolithography (STL) model, which is a native digital format of AM, and assembled as a test piece. The thermal expansions of the specimens were measured using a laser scanning dilatometer. Negative thermal expansion corresponding to less than -1 × 10-4 K-1 was observed for each test piece of the N = 3 experiment.

  16. The role of anisotropic expansion for pulmonary acinar aerosol deposition.

    PubMed

    Hofemeier, Philipp; Sznitman, Josué

    2016-10-03

    Lung deformations at the local pulmonary acinar scale are intrinsically anisotropic. Despite progress in imaging modalities, the true heterogeneous nature of acinar expansion during breathing remains controversial, where our understanding of inhaled aerosol deposition still widely emanates from studies under self-similar, isotropic wall motions. Building on recent 3D models of multi-generation acinar networks, we explore in numerical simulations how different hypothesized scenarios of anisotropic expansion influence deposition outcomes of inhaled aerosols in the acinar depths. While the broader range of particles acknowledged to reach the acinar region (d p =0.005-5.0μm) are largely unaffected by the details of anisotropic expansion under tidal breathing, our results suggest nevertheless that anisotropy modulates the deposition sites and fractions for a narrow band of sub-micron particles (d p ~0.5-0.75μm), where the fate of aerosols is greatly intertwined with local convective flows. Our findings underscore how intrinsic aerosol motion (i.e. diffusion, sedimentation) undermines the role of anisotropic wall expansion that is often attributed in determining aerosol mixing and acinar deposition. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Primary care appointment availability and nonphysician providers one year after Medicaid expansion.

    PubMed

    Tipirneni, Renuka; Rhodes, Karin V; Hayward, Rodney A; Lichtenstein, Richard L; Choi, HwaJung; Reamer, Elyse N; Davis, Matthew M

    2016-06-01

    With insurance enrollment greater than expected under the Affordable Care Act, uncertainty about the availability and timeliness of healthcare services for newly insured individuals has increased. We examined primary care appointment availability and wait times for new Medicaid and privately insured patients before and after Medicaid expansion in Michigan. Simulated patient ("secret shopper") study. Extended follow-up of a previously reported simulated patient ("secret shopper") study assessing accessibility of routine new patient appointments in a stratified proportionate random sample of Michigan primary care practices before versus 4, 8, and 12 months after Medicaid expansion. During the study period, approximately 600,000 adults enrolled in Michigan's Medicaid expansion program, representing 57% of the previously uninsured nonelderly adult population. One year after expansion, we found that appointment availability remained increased by 6 percentage points for new Medicaid patients (95% CI, 1.6-11.1) and decreased by 2 percentage points for new privately insured patients (95% CI, -0.5 to -3.8). Over the same period, the proportion of appointments scheduled with nonphysician providers (nurse practitioners or physician assistants) increased from 8% to 21% of Medicaid appointments (95% CI, 5.6-20.2) and from 11% to 19% of private-insurance appointments (95% CI, 1.3-14.1). Median wait times remained stable for new Medicaid patients and increased slightly for new privately insured patients, both remaining within 2 weeks. During the first year following Medicaid expansion in Michigan, appointment availability for new Medicaid patients increased, a greater proportion of appointments could be obtained with nonphysician providers, and wait times remained within 2 weeks.

  18. 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

  19. 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

  20. Thermal expansion of vitrified blood vessels permeated with DP6 and synthetic ice modulators.

    PubMed

    Eisenberg, David P; Taylor, Michael J; Jimenez-Rios, Jorge L; Rabin, Yoed

    2014-06-01

    This study provides thermal expansion data for blood vessels permeated with the cryoprotective cocktail DP6, when combined with selected synthetic ice modulators (SIMs): 12% polyethylene glycol 400, 6% 1,3-cyclohexanediol, and 6% 2,3-butanediol. The general classification of SIMs includes molecules that modulate ice nucleation and growth, or possess properties of stabilizing the amorphous state, by virtue of their chemical structure and at concentrations that are not explained on a purely colligative basis. The current study is part of an ongoing effort to characterize thermo-mechanical effects on structural integrity of cryopreserved materials, where thermal expansion is the driving mechanism to thermo-mechanical stress. This study focuses on the lower part of the cryogenic temperature range, where the cryoprotective agent (CPA) behaves as a solid for all practical applications. By combining results obtained in the current study with literature data on the thermal expansion in the upper part of the cryogenic temperature range, unified thermal expansion curves are presented. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Comparison among Magnus/Floquet/Fer expansion schemes in solid-state NMR

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

    Takegoshi, K., E-mail: takeyan@kuchem.kyoto-u.ac.jp; Miyazawa, Norihiro; Sharma, Kshama

    2015-04-07

    We here revisit expansion schemes used in nuclear magnetic resonance (NMR) for the calculation of effective Hamiltonians and propagators, namely, Magnus, Floquet, and Fer expansions. While all the expansion schemes are powerful methods there are subtle differences among them. To understand the differences, we performed explicit calculation for heteronuclear dipolar decoupling, cross-polarization, and rotary-resonance experiments in solid-state NMR. As the propagator from the Fer expansion takes the form of a product of sub-propagators, it enables us to appreciate effects of time-evolution under Hamiltonians with different orders separately. While 0th-order average Hamiltonian is the same for the three expansion schemes withmore » the three cases examined, there is a case that the 2nd-order term for the Magnus/Floquet expansion is different from that obtained with the Fer expansion. The difference arises due to the separation of the 0th-order term in the Fer expansion. The separation enables us to appreciate time-evolution under the 0th-order average Hamiltonian, however, for that purpose, we use a so-called left-running Fer expansion. Comparison between the left-running Fer expansion and the Magnus expansion indicates that the sign of the odd orders in Magnus may better be reversed if one would like to consider its effect in order.« less

  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. Multiplicative-Generated Dark Matter Accelerated Cosmic Expansion

    NASA Astrophysics Data System (ADS)

    Zhang, Weijia; Kelly, Neil

    2011-02-01

    In order to make the increase of Astronomical Unit consistent with observations of the Earth's orbital period variation, an increase of the Solar dark matter as 10-12/yr is needed. This implies that dark matter has an increase ratio, and therefore supports Dirac's multiplicative matter creation, and provides another explanation to the accelerating expansion of the universe. This is in accordance with the analysis on orbital dynamics around a mass varying central body to the phenomenon of accretion of dark matter assumed not self-annihilating-on the Sun and the major bodies of the solar system due to its motion throughout the Milky Way halo. Dark matter and dark energy, two of the most vexing problems in science today which dominate the universe, comprising some 96 percent of all mass and energy, seem to be two sides of the same coin.

  4. Investigation of Key Parameters of Rock Cracking Using the Expansion of Vermiculite Materia.

    PubMed

    Ahn, Chi-Hyung; Hu, Jong Wan

    2015-10-12

    The demand for the development of underground spaces has been sharply increased in lieu of saturated ground spaces because the residents of cities have steadily increased since the 1980s. The traditional widely used excavation methods ( i.e ., explosion and shield) have caused many problems, such as noise, vibration, extended schedule, and increased costs. The vibration-free (and explosion-free) excavation method has currently attracted attention in the construction site because of the advantage of definitively solving these issues. For such reason, a new excavation method that utilizes the expansion of vermiculite with relatively fewer defects is proposed in this study. In general, vermiculite materials are rapidly expanded in volume when they receive thermal energy. Expansion pressure can be produced by thermal expansion of vermiculite in a steel tube, and measured by laboratory tests. The experimental tests are performed with various influencing parameters in an effort to seek the optimal condition to effectively increase expansion pressure at the same temperature. Then, calibrated expansion pressure is estimated, and compared to each model. After analyzing test results for expansion pressure, it is verified that vermiculite expanded by heat can provide enough internal pressure to break hard rock during tunneling work.

  5. 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…

  6. A new framework for modeling urban land expansion in peri-urban area by combining multi-source datasets and data assimilation

    NASA Astrophysics Data System (ADS)

    Zhang, Z.; Xiao, R.; Li, X.

    2015-12-01

    Peri-urban area is a new type region under the impacts of both rural Industrialization and the radiation of metropolitan during rapid urbanization. Due to its complex natural and social characteristics and unique development patterns, many problems such as environmental pollution and land use waste emerged, which became an urgent issue to be addressed. Study area in this paper covers three typical peri-urban districts (Pudong, Fengxian and Jinshan), which around the Shanghai inner city. By coupling cellular automata and multi-agent system model as the basic tools, this research focus on modelling the urban land expansion and driving mechanism in peri-urban area. The big data is aslo combined with the Bayesian maximum entropy method (BME) for spatiotemporal prediction of multi-source data, which expand the dataset of urban expansion models. Data assimilation method is used to optimize the parameters of the coupling model and minimize the uncertainty of observations, improving the precision of future simulation in peri-urban area. By setting quantitative parameters, the coupling model can effectively improve the simulation of the process of urban land expansion under different policies and management schemes, in order to provide scientificimplications for new urbanization strategy. In this research, we precise the urban land expansion simulation and prediction for peri-urban area, expand the scopes and selections of data acquisition measurements and methods, develop the new applications of the data assimilation method in geographical science, provide a new idea for understanding the inherent rules of urban land expansion, and give theoretical and practical support for the peri-urban area in urban planning and decision making.

  7. MutSβ and histone deacetylase complexes promote expansions of trinucleotide repeats in human cells

    PubMed Central

    Gannon, Anne-Marie M.; Frizzell, Aisling; Healy, Evan; Lahue, Robert S.

    2012-01-01

    Trinucleotide repeat (TNR) expansions cause at least 17 heritable neurological diseases, including Huntington’s disease. Expansions are thought to arise from abnormal processing of TNR DNA by specific trans-acting proteins. For example, the DNA repair complex MutSβ (MSH2–MSH3 heterodimer) is required in mice for on-going expansions of long, disease-causing alleles. A distinctive feature of TNR expansions is a threshold effect, a narrow range of repeat units (∼30–40 in humans) at which mutation frequency rises dramatically and disease can initiate. The goal of this study was to identify factors that promote expansion of threshold-length CTG•CAG repeats in a human astrocytic cell line. siRNA knockdown of the MutSβ subunits MSH2 or MSH3 impeded expansions of threshold-length repeats, while knockdown of the MutSα subunit MSH6 had no effect. Chromatin immunoprecipitation experiments indicated that MutSβ, but not MutSα, was enriched at the TNR. These findings imply a direct role for MutSβ in promoting expansion of threshold-length CTG•CAG tracts. We identified the class II deacetylase HDAC5 as a novel promoting factor for expansions, joining the class I deacetylase HDAC3 that was previously identified. Double knockdowns were consistent with the possibility that MutSβ, HDAC3 and HDAC5 act through a common pathway to promote expansions of threshold-length TNRs. PMID:22941650

  8. 12 CFR 34.84 - Future bank expansion.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 1 2011-01-01 2011-01-01 false Future bank expansion. 34.84 Section 34.84 Banks and Banking COMPTROLLER OF THE CURRENCY, DEPARTMENT OF THE TREASURY REAL ESTATE LENDING AND APPRAISALS Other Real Estate Owned § 34.84 Future bank expansion. A national bank normally should use real...

  9. Boson expansions based on the random phase approximation representation

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

    Pedrocchi, V.G.; Tamura, T.

    1984-04-01

    A new boson expansion theory based on the random phase approximation is presented. The boson expansions are derived here directly in the random phase approximation representation with the help of a technique that combines the use of the Usui operator with that of a new bosonization procedure, called the term-by-term bosonization method. The present boson expansion theory is constructed by retaining a single collective quadrupole random phase approximation component, a truncation that allows for a perturbative treatment of the whole problem. Both Hermitian, as well as non-Hermitian boson expansions, valid for even nuclei, are obtained.

  10. External combustion engine having a combustion expansion chamber

    NASA Astrophysics Data System (ADS)

    Duva, Anthony W.

    1993-03-01

    This patent application discloses an external combustion engine having a combustion expansion chamber. The engine includes a combustion chamber for generating a high-pressure, energized gas from a monopropellant fuel, and a cylinder for receiving the energized gas through a rotary valve to perform work on a cylinder disposed therein. A baffle plate is positioned between the combustion area and expansion area for reducing the pressure of the gas. The combustion area and expansion area are separated by a baffle plate having a flow area which is sufficiently large to eliminate the transmission of pressure pulsations from the combustion area to the expansion area while being small enough to provide for substantially complete combustion in the combustion area. The engine is particularly well suited for use in a torpedo.

  11. A strictly Markovian expansion for plasma turbulence theory

    NASA Technical Reports Server (NTRS)

    Jones, F. C.

    1978-01-01

    The collision operator that appears in the equation of motion for a particle distribution function that has been averaged over an ensemble of random Hamiltonians is non-Markovian. It is non-Markovian in that it involves a propagated integral over the past history of the ensemble averaged distribution function. All formal expansions of this nonlinear collision operator to date preserve this non-Markovian character term by term yielding an integro-differential equation that must be converted to a diffusion equation by an additional approximation. In this note we derive an expansion of the collision operator that is strictly Markovian to any finite order and yields a diffusion equation as the lowest non-trivial order. The validity of this expansion is seen to be the same as that of the standard quasi-linear expansion.

  12. Finnish Higher Education Expansion and Regional Policy

    ERIC Educational Resources Information Center

    Saarivirta, Toni

    2010-01-01

    This paper concentrates on the expansion of Finnish higher education between the 1960s and 1970s, exposes its background in the light of the policy decisions that were made, compares the unique features of this expansion with those of certain other countries, discusses the impact of the controlled "top down" governance of higher…

  13. Spherical-wave expansions of piston-radiator fields.

    PubMed

    Wittmann, R C; Yaghjian, A D

    1991-09-01

    Simple spherical-wave expansions of the continuous-wave fields of a circular piston radiator in a rigid baffle are derived. These expansions are valid throughout the illuminated half-space and are useful for efficient numerical computation in the near-field region. Multipole coefficients are given by closed-form expressions which can be evaluated recursively.

  14. 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…

  15. The Expansion Segments of 28S Ribosomal RNA Extensively Match Human Messenger RNAs

    PubMed Central

    Parker, Michael S.; Balasubramaniam, Ambikaipakan; Sallee, Floyd R.; Parker, Steven L.

    2018-01-01

    Eukaryote ribosomal RNAs (rRNAs) have expanded in the course of phylogeny by addition of nucleotides in specific insertion areas, the expansion segments. These number about 40 in the larger (25–28S) rRNA (up to 2,400 nucleotides), and about 12 in the smaller (18S) rRNA (<700 nucleotides). Expansion of the larger rRNA shows a clear phylogenetic increase, with a dramatic rise in mammals and especially in hominids. Substantial portions of expansion segments in this RNA are not bound to ribosomal proteins, and may engage extraneous interactants, including messenger RNAs (mRNAs). Studies on the ribosome-mRNA interaction have focused on proteins of the smaller ribosomal subunit, with some examination of 18S rRNA. However, the expansion segments of human 28S rRNA show much higher density and numbers of mRNA matches than those of 18S rRNA, and also a higher density and match numbers than its own core parts. We have studied that with frequent and potentially stable matches containing 7–15 nucleotides. The expansion segments of 28S rRNA average more than 50 matches per mRNA even assuming only 5% of their sequence as available for such interaction. Large expansion segments 7, 15, and 27 of 28S rRNA also have copious long (≥10-nucleotide) matches to most human mRNAs, with frequencies much higher than in other 28S rRNA parts. Expansion segments 7 and 27 and especially segment 15 of 28S rRNA show large size increase in mammals compared to other metazoans, which could reflect a gain of function related to interaction with non-ribosomal partners. The 28S rRNA expansion segment 15 shows very high increments in size, guanosine, and cytidine nucleotide content and mRNA matching in mammals, and especially in hominids. With these segments (but not with other 28S rRNA or any 18S rRNA expansion segments) the density and number of matches are much higher in 5′-terminal than in 3′-terminal untranslated mRNA regions, which may relate to mRNA mobilization via 5′ termini. Matches

  16. Income eligibility thresholds, premium contributions, and children's coverage outcomes: a study of CHIP expansions.

    PubMed

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

    2013-04-01

    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. 2002-2009 Annual Social and Economic Supplements of the Current Population Survey linked to data from multiple secondary data sources. 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. 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). 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. © Health Research and Educational Trust.

  17. Expansion of a cold non-neutral plasma slab

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

    Karimov, A. R.; Department of Electrophysical Facilities, National Research Nuclear University MEPhI, Kashirskoye shosse 31, Moscow 115409; Yu, M. Y., E-mail: myyu@zju.edu.cn

    2014-12-15

    Expansion of the ion and electron fronts of a cold non-neutral plasma slab with a quasi-neutral core bounded by layers containing only ions is investigated analytically and exact solutions are obtained. It is found that on average, the plasma expansion time scales linearly with the initial inverse ion plasma frequency as well as the degree of charge imbalance, and no expansion occurs if the cold plasma slab is stationary and overall neutral. However, in both cases, there can exist prominent oscillations on the electron front.

  18. The poor man's Geographic Information System: plot expansion factors

    Treesearch

    Paul C. Van Deusen

    2007-01-01

    Plot expansion factors can serve as a crude Geographic Information System for users of Forest Inventory and Analysis (FIA) data. Each FIA plot has an associated expansion factor that is often interpreted as the number of forested acres that the plot represents. The derivation of expansion factors is discussed and it is shown that the mapped plot design requires a...

  19. Expansion of Mandibular Knife-Edge Ridge and Simultaneous Implant Placement to Retain Overdentures: One-Year Clinical and Radiographic Results of a Prospective Study.

    PubMed

    ELsyad, Moustafa Abdou; Hammouda, Nelly Ibrahim

    2017-02-01

    The aim of this study was to evaluate and compare the clinical and radiographic outcomes of two implants placed in expanded mandibular knife-edge ridge and implants placed in unexpanded ridges to retain overdentures. Fifteen completely edentulous patients with knife-edge ridges at canine areas of the mandible received two implants using the ridge expansion technique (study group, SG). Expansion was performed using piezoelectric corticotomy, and self-threading expanders. The control group (CG) comprised patients who received two-implant at canine areas without ridge expansion but were all case matched to SG and served as historical cohort. In both groups, mandibular overdentures were connected to the implants with Locator attachments 3 months after implant placement. Clinical (Plaque index; PI, Gingival index; GI, Probing depth; PD, and implant stability; ISQ) and radiographic (Vertical bone loss; VBL) parameters were recorded at time of overdenture insertion (base line, T0), 6 months (T6), and 12 months (T12) after insertion. The cumulative success rates were 100% and 96.4% for CG and SG, respectively, without significant difference between groups. All tested parameters increased significantly with advance of time in both groups. There was no significant difference in PI, GI, PD, and ISQ between groups. However, SG recorded significant higher VBL than CG at T6 and T12. Expansion of mandibular knife edge ridge and simultaneous placement of implants to retain overdentures is associated with clinic and radiographic outcomes comparable to implants placed in unexpanded ridges after 1 year. However, long term randomized controlled trials with sufficient sample size are still needed to ensure the findings of the present study. © 2016 Wiley Periodicals, Inc.

  20. Novel expansion techniques for skin grafts

    PubMed Central

    Kadam, Dinesh

    2016-01-01

    The quest for skin expansion is not restricted to cover a large area alone, but to produce acceptable uniform surfaces, robust engraftment to withstand mechanical shear and infection, with a minimal donor morbidity. Ease of the technique, shorter healing period and reproducible results are essential parameters to adopt novel techniques. Significant advances seen in four fronts of autologous grafting are: (1) Dermal–epidermal graft expansion techniques, (2) epidermal graft harvests technique, (3) melanocyte-rich basal cell therapy for vitiligo and (4) robust and faster autologous cell cultures. Meek's original concept that the sum of perimeter of smaller grafts is larger than the harvested graft, and smaller the graft size, the greater is the potential for regeneration is witnessed in newer modification. Further, as graft size becomes smaller or minced, these micrografts can survive on the wound bed exudate irrespective of their dermal orientation. Expansion produced by 4 mm × 4 mm sized Meek micrografts is 10-folds, similarly 0.8 mm × 0.8 mm size micrografts produce 100-fold expansion, which becomes 700-fold with pixel grafts of 0.3 mm × 0.3 mm size. Fractional skin harvest is another new technique with 700 μ size full thickness graft. These provide instant autologous non-cultured graft to cover extensive areas with similar quality of engraftment surface as split skin grafts. Newer tools for epidermal blister graft harvest quickly, with uniform size to produce 7-fold expansions with reproducible results. In addition, donor area heals faster with minimal scar. Melanocyte-rich cell suspension is utilised in vitiligo surgery tapping the potential of hair root melanocytes. Further advances in the cell culture to reduce the cultivation time and provide stronger epidermal sheets with dermal carrier are seen in trials. PMID:27274117

  1. Screening for the C9ORF72 repeat expansion in a greek frontotemporal dementia cohort.

    PubMed

    Kartanou, Chrisoula; Karadima, Georgia; Koutsis, Georgios; Breza, Marianthi; Papageorgiou, Sokratis G; Paraskevas, George P; Kapaki, Elisabeth; Panas, Marios

    2018-02-01

    The C9orf72 repeat expansion is a common genetic cause of frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS) in European populations. A previous study has reported a high frequency of the expansion in Greek ALS. However, no data have been reported on the frequency of the expansion in Greek FTD. Currently, we investigated the frequency of the C9orfF72 expansion in a well-characterized cohort of 64 Greek FTD patients. We detected the C9orf72 repeat expansion in 9.3% of cases. Overall, 27.7% of familial and 2.2% of sporadic cases were expansion-positive. Five out of 6 cases had a diagnosis of behavioral variant FTD. All expansion-positive cases had fairly typical FTD presentations. Clinical features included motor neuron disease, Parkinsonism and hallucinations. We conclude that the overall frequency of C9orf72-positive cases in Greek FTD is high, comparable to Greek ALS, similar to some Western European, but significantly higher than some Mediterranean FTD populations.

  2. Cerebellar neuronal loss in amyotrophic lateral sclerosis cases with ATXN2 intermediate repeat expansions.

    PubMed

    Tan, Rachel H; Kril, Jillian J; McGinley, Ciara; Hassani, Mohammad; Masuda-Suzukake, Masami; Hasegawa, Masato; Mito, Remika; Kiernan, Matthew C; Halliday, Glenda M

    2016-02-01

    Despite evidence suggesting that the cerebellum may be targeted in amyotrophic lateral sclerosis (ALS), particularly in cases with repeat expansions in the ATXN2 and C9ORF72 genes, the integrity of cerebellar neurons has yet to be examined. The present study undertakes a histopathological analysis to assess the impact of these repeat expansions on cerebellar neurons and determine whether similar cerebellar pathology occurs in sporadic disease. Purkinje and granule cells were quantified in the vermis and lateral cerebellar hemispheres of ALS cases with repeat expansions in the ATXN2 and C9ORF72 genes, sporadic disease, and sporadic progressive muscular atrophy with only lower motor neuron degeneration. ALS cases with intermediate repeat expansions in the ATXN2 gene demonstrate a significant loss in Purkinje cells in the cerebellar vermis only. Despite ALS cases with expansions in the C9ORF72 gene having the highest burden of inclusion pathology, no neuronal loss was observed in this group. Neuronal numbers were also unchanged in sporadic ALS and sporadic PMA cases. The present study has established a selective loss of Purkinje cells in the cerebellar vermis of ALS cases with intermediate repeat expansions in the ATXN2 gene, suggesting a divergent pathogenic mechanism independent of upper and lower motor neuron degeneration in ALS. We discuss these findings in the context of large repeat expansions in ATXN2 and spinocerebellar ataxia type 2, providing evidence that intermediate repeats in ATXN2 cause significant, albeit less substantial, spinocerebellar damage compared with longer repeats in ATXN2. © 2016 American Neurological Association.

  3. Characterization of demographic expansions from pairwise comparisons of linked microsatellite haplotypes.

    PubMed

    Navascués, Miguel; Hardy, Olivier J; Burgarella, Concetta

    2009-03-01

    This work extends the methods of demographic inference based on the distribution of pairwise genetic differences between individuals (mismatch distribution) to the case of linked microsatellite data. Population genetics theory describes the distribution of mutations among a sample of genes under different demographic scenarios. However, the actual number of mutations can rarely be deduced from DNA polymorphisms. The inclusion of mutation models in theoretical predictions can improve the performance of statistical methods. We have developed a maximum-pseudolikelihood estimator for the parameters that characterize a demographic expansion for a series of linked loci evolving under a stepwise mutation model. Those loci would correspond to DNA polymorphisms of linked microsatellites (such as those found on the Y chromosome or the chloroplast genome). The proposed method was evaluated with simulated data sets and with a data set of chloroplast microsatellites that showed signal for demographic expansion in a previous study. The results show that inclusion of a mutational model in the analysis improves the estimates of the age of expansion in the case of older expansions.

  4. Renal sodium reabsorption following induction of and recovery from volume expansion

    NASA Technical Reports Server (NTRS)

    Knight, T. F.; Weinman, E. J.

    1977-01-01

    In the rat, infusion of a volume of isotonic saline equal to 2% of body weight resulted in an 82% increase in the delivery of filtrate out of the proximal tubule but little or, in some animals, no change in the urinary excretion of sodium. By contrast, further degrees of volume expansion resulted in lesser increases in the distal delivery of filtrate, but were associated with a marked increase in the urinary excretion of sodium. Sixty minutes following completion of volume expansion, while the animals were still in positive sodium balance, the urinary excretion of sodium decreased 52% compared to a decrease of only 24% in the distal delivery of filtrate. During the course of progressive volume expansion and during the recovery phase, there was a dissociation between alterations in sodium reabsorption in the proximal convoluted tubule and in the whole kidney. These studies indicate that although the proximal tubule is more sensitive to changes in the extracellular fluid volume, distal nephron sites are ultimately responsible both for the natriuresis of volume expansion and the relative antinatriuresis of the recovery periods.

  5. Urban Intensification and Expansion in Sub-Saharan Africa: Impacts on Urban Agriculture and Food Security

    NASA Astrophysics Data System (ADS)

    Uzokwe, V. N. E. N.; Muchelo, R. O.; Odeh, I. A.

    2015-12-01

    In Sub-Saharan Africa (SSA), urban intensification and expansion are increasing at alarming rates due to rapid population growth and rural-to-urban migration. This has led to the premise that the proportion of SSA urban residents most vulnerable to food insecurity is the highest in the world. Using a focused survey and multi-temporal (decadal) land use/cover classification of Landsat images, we explored the effect of urban intensification and expansion on urban agriculture and food security, focusing on a megacity and a regional center in Uganda: Kampala and Mbarara, respectively. We found that food insecurity arose due to a number of reasons, among which are: i) expansion and intensification of of urban settlements into previously productive agricultural lands in urban and peri-urban areas; ii) loss of predominantly young (rural agricultural) adult labor force to urban centers, leading to decline in rural food production; iii) lack of proper urban planning incorporating green and agricultural development leading to low productive market garden systems. We discussed these outcomes in light of existing studies which estimated that urban agriculture alone supports over 800 million people globally and accounts for 15-20% of world food supply. In spite of this relatively low contribution by urban/peri-urban agriculture, it probably accounts for higher proportion of food supply to urban poor in SSA and thus are most vulnerable to the loss of urban and peri-urban agricultural land. Further recommendations require policy makers and urban planners to team up to design a suitable framework for sustainable urban planning and development.

  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. Multipole expansion method for supernova neutrino oscillations

    DOE PAGES

    Duan, Huaiyu; Shalgar, Shashank

    2014-10-31

    Here, we demonstrate a multipole expansion method to calculate collective neutrino oscillations in supernovae using the neutrino bulb model. We show that it is much more efficient to solve multi-angle neutrino oscillations in multipole basis than in angle basis. The multipole expansion method also provides interesting insights into multi-angle calculations that were accomplished previously in angle basis.

  8. Expansion patterns and parallaxes for planetary nebulae

    NASA Astrophysics Data System (ADS)

    Schönberner, D.; Balick, B.; Jacob, R.

    2018-02-01

    Aims: We aim to determine individual distances to a small number of rather round, quite regularly shaped planetary nebulae by combining their angular expansion in the plane of the sky with a spectroscopically measured expansion along the line of sight. Methods: We combined up to three epochs of Hubble Space Telescope imaging data and determined the angular proper motions of rim and shell edges and of other features. These results are combined with measured expansion speeds to determine individual distances by assuming that line of sight and sky-plane expansions are equal. We employed 1D radiation-hydrodynamics simulations of nebular evolution to correct for the difference between the spectroscopically measured expansion velocities of rim and shell and of their respective shock fronts. Results: Rim and shell are two independently expanding entities, driven by different physical mechanisms, although their model-based expansion timescales are quite similar. We derive good individual distances for 15 objects, and the main results are as follows: (i) distances derived from rim and shell agree well; (ii) comparison with the statistical distances in the literature gives reasonable agreement; (iii) our distances disagree with those derived by spectroscopic methods; (iv) central-star "plateau" luminosities range from about 2000 L⊙ to well below 10 000 L⊙, with a mean value at about 5000 L⊙, in excellent agreement with other samples of known distance (Galactic bulge, Magellanic Clouds, and K648 in the globular cluster M 15); (v) the central-star mass range is rather restricted: from about 0.53 to about 0.56 M⊙, with a mean value of 0.55 M⊙. Conclusions: The expansion measurements of nebular rim and shell edges confirm the predictions of radiation-hydrodynamics simulations and offer a reliable method for the evaluation of distances to suited objects. Results of this paper are based on observations made with the NASA/ESA Hubble Space Telescope in Cycle 16 (GO11122

  9. Contrast Enhancement without Transient Map Expansion for Species-Specific Vocalizations in Core Auditory Cortex during Learning.

    PubMed

    Shepard, Kathryn N; Chong, Kelly K; Liu, Robert C

    2016-01-01

    Tonotopic map plasticity in the adult auditory cortex (AC) is a well established and oft-cited measure of auditory associative learning in classical conditioning paradigms. However, its necessity as an enduring memory trace has been debated, especially given a recent finding that the areal expansion of core AC tuned to a newly relevant frequency range may arise only transiently to support auditory learning. This has been reinforced by an ethological paradigm showing that map expansion is not observed for ultrasonic vocalizations (USVs) or for ultrasound frequencies in postweaning dams for whom USVs emitted by pups acquire behavioral relevance. However, whether transient expansion occurs during maternal experience is not known, and could help to reveal the generality of cortical map expansion as a correlate for auditory learning. We thus mapped the auditory cortices of maternal mice at postnatal time points surrounding the peak in pup USV emission, but found no evidence of frequency map expansion for the behaviorally relevant high ultrasound range in AC. Instead, regions tuned to low frequencies outside of the ultrasound range show progressively greater suppression of activity in response to the playback of ultrasounds or pup USVs for maternally experienced animals assessed at their pups' postnatal day 9 (P9) to P10, or postweaning. This provides new evidence for a lateral-band suppression mechanism elicited by behaviorally meaningful USVs, likely enhancing their population-level signal-to-noise ratio. These results demonstrate that tonotopic map enlargement has limits as a construct for conceptualizing how experience leaves neural memory traces within sensory cortex in the context of ethological auditory learning.

  10. Expansion of transient operating data

    NASA Astrophysics Data System (ADS)

    Chipman, Christopher; Avitabile, Peter

    2012-08-01

    Real time operating data is very important to understand actual system response. Unfortunately, the amount of physical data points typically collected is very small and often interpretation of the data is difficult. Expansion techniques have been developed using traditional experimental modal data to augment this limited set of data. This expansion process allows for a much improved description of the real time operating response. This paper presents the results from several different structures to show the robustness of the technique. Comparisons are made to a more complete set of measured data to validate the approach. Both analytical simulations and actual experimental data are used to illustrate the usefulness of the technique.

  11. Clonal Expansion during Staphylococcus aureus Infection Dynamics Reveals the Effect of Antibiotic Intervention

    PubMed Central

    McVicker, Gareth; Prajsnar, Tomasz K.; Williams, Alexander; Wagner, Nelly L.; Boots, Michael; Renshaw, Stephen A.; Foster, Simon J.

    2014-01-01

    To slow the inexorable rise of antibiotic resistance we must understand how drugs impact on pathogenesis and influence the selection of resistant clones. Staphylococcus aureus is an important human pathogen with populations of antibiotic-resistant bacteria in hospitals and the community. Host phagocytes play a crucial role in controlling S. aureus infection, which can lead to a population “bottleneck” whereby clonal expansion of a small fraction of the initial inoculum founds a systemic infection. Such population dynamics may have important consequences on the effect of antibiotic intervention. Low doses of antibiotics have been shown to affect in vitro growth and the generation of resistant mutants over the long term, however whether this has any in vivo relevance is unknown. In this work, the population dynamics of S. aureus pathogenesis were studied in vivo using antibiotic-resistant strains constructed in an isogenic background, coupled with systemic models of infection in both the mouse and zebrafish embryo. Murine experiments revealed unexpected and complex bacterial population kinetics arising from clonal expansion during infection in particular organs. We subsequently elucidated the effect of antibiotic intervention within the host using mixed inocula of resistant and sensitive bacteria. Sub-curative tetracycline doses support the preferential expansion of resistant microorganisms, importantly unrelated to effects on growth rate or de novo resistance acquisition. This novel phenomenon is generic, occurring with methicillin-resistant S. aureus (MRSA) in the presence of β-lactams and with the unrelated human pathogen Pseudomonas aeruginosa. The selection of resistant clones at low antibiotic levels can result in a rapid increase in their prevalence under conditions that would previously not be thought to favor them. Our results have key implications for the design of effective treatment regimes to limit the spread of antimicrobial resistance, where

  12. Expansion of Titan atmosphere

    NASA Astrophysics Data System (ADS)

    Salem, S.; Moslem, W. M.; Radi, A.

    2017-05-01

    Self-similar plasma expansion approach is used to solve a plasma model based on the losing phenomenon of Titan atmospheric composition. To this purpose, a set of hydrodynamic fluid equations describing a plasma consisting of two positive ions with different masses and isothermal electrons is used. With the aid of self-similar transformation, numerical solution of the fluid equations has been performed to examine the density, velocity, and potential profiles. The effects of different plasma parameters, i.e., density and temperature ratios, are studied on the expanding plasma profiles. The present investigation could be useful to recognize the ionized particles escaping from Titan atmosphere.

  13. Expansive cements for the manufacture of the concrete protective bandages

    NASA Astrophysics Data System (ADS)

    Yakymechko, Yaroslav; Voloshynets, Vladyslav

    2017-12-01

    One of the promising directions of the use of expansive cements is making the protective bandages for the maintenance of pipelines. Bandages expansive application of the compositions of the pipeline reinforce the damaged area and reduce stress due to compressive stress in the cylindrical area. Such requirements are best suited for expansive compositions obtained from portland cement and modified quicklime. The article presents the results of expansive cements based on quick lime in order to implement protective bandages pipelines.

  14. Off-diagonal series expansion for quantum partition functions

    NASA Astrophysics Data System (ADS)

    Hen, Itay

    2018-05-01

    We derive an integral-free thermodynamic perturbation series expansion for quantum partition functions which enables an analytical term-by-term calculation of the series. The expansion is carried out around the partition function of the classical component of the Hamiltonian with the expansion parameter being the strength of the off-diagonal, or quantum, portion. To demonstrate the usefulness of the technique we analytically compute to third order the partition functions of the 1D Ising model with longitudinal and transverse fields, and the quantum 1D Heisenberg model.

  15. Self-similar expansion of adiabatic electronegative dusty plasma

    NASA Astrophysics Data System (ADS)

    Shahmansouri, M.; Bemooni, A.; Mamun, A. A.

    2017-12-01

    The self-similar expansion of an adiabatic electronegative dusty plasma (consisting of inertialess adiabatic electrons, inertialess adiabatic ions and inertial adiabatic negatively charged dust fluids) is theoretically investigated by employing the self-similar approach. It is found that the effects of the plasma adiabaticity (represented by the adiabatic index ) and dusty plasma parameters (determined by dust temperature and initial dust population) significantly modify the nature of the plasma expansion. The implications of our results are expected to play an important role in understanding the physics of the expansion of space and laboratory electronegative dusty plasmas.

  16. Meta-Analysis of Predictive Significance of the Black Hole Sign for Hematoma Expansion in Intracerebral Hemorrhage.

    PubMed

    Zheng, Jun; Yu, Zhiyuan; Guo, Rui; Li, Hao; You, Chao; Ma, Lu

    2018-04-27

    Hematoma expansion is related to unfavorable prognosis in intracerebral hemorrhage (ICH). The black hole sign is a novel marker on non-contrast computed tomography for predicting hematoma expansion. However, its predictive values are different in previous studies. Thus, this meta-analysis was conducted to evaluate the predictive significance of the black hole sign for hematoma expansion in ICH. A systematic literature search was performed. Original researches on the association between the black hole sign and hematoma expansion in ICH were included. Sensitivity and specificity were pooled to assess the predictive accuracy. Summary receiver operating characteristics curve (SROC) was developed. Deeks' funnel plot asymmetry test was used to assess the publication bias. Five studies with a total of 1495 patients were included in this study. The pooled sensitivity and specificity of the black hole sign for predicting hematoma expansion were 0.30 and 0.91, respectively. The area under the curve was 0.78 in SROC curve. There was no significant publication bias. This meta-analysis shows that the black hole sign is a helpful imaging marker for predicting hematoma expansion in ICH. Although the black hole sign has a relatively low sensitivity, its specificity is relatively high. Copyright © 2018 Elsevier Inc. All rights reserved.

  17. 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.

  18. Engineering Technical Support Center Annual Report Fiscal Year 2016

    EPA Science Inventory

    This report highlights significant projects that the ETSC supported in fiscal year 2016. These projects have addressed an array of environmental scenarios, including, but not limited to remote mining contamination, expansive landfill waste, cumulative impacts from multiple contam...

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

    PubMed

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

    2017-02-01

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

  20. Synonym extraction and abbreviation expansion with ensembles of semantic spaces.

    PubMed

    Henriksson, Aron; Moen, Hans; Skeppstedt, Maria; Daudaravičius, Vidas; Duneld, Martin

    2014-02-05

    Terminologies that account for variation in language use by linking synonyms and abbreviations to their corresponding concept are important enablers of high-quality information extraction from medical texts. Due to the use of specialized sub-languages in the medical domain, manual construction of semantic resources that accurately reflect language use is both costly and challenging, often resulting in low coverage. Although models of distributional semantics applied to large corpora provide a potential means of supporting development of such resources, their ability to isolate synonymy from other semantic relations is limited. Their application in the clinical domain has also only recently begun to be explored. Combining distributional models and applying them to different types of corpora may lead to enhanced performance on the tasks of automatically extracting synonyms and abbreviation-expansion pairs. A combination of two distributional models - Random Indexing and Random Permutation - employed in conjunction with a single corpus outperforms using either of the models in isolation. Furthermore, combining semantic spaces induced from different types of corpora - a corpus of clinical text and a corpus of medical journal articles - further improves results, outperforming a combination of semantic spaces induced from a single source, as well as a single semantic space induced from the conjoint corpus. A combination strategy that simply sums the cosine similarity scores of candidate terms is generally the most profitable out of the ones explored. Finally, applying simple post-processing filtering rules yields substantial performance gains on the tasks of extracting abbreviation-expansion pairs, but not synonyms. The best results, measured as recall in a list of ten candidate terms, for the three tasks are: 0.39 for abbreviations to long forms, 0.33 for long forms to abbreviations, and 0.47 for synonyms. This study demonstrates that ensembles of semantic spaces can