Sample records for valodas tulkojusi stella

  1. More STELLA Narratives.

    ERIC Educational Resources Information Center

    Doecke, Brenton

    2001-01-01

    Presents six brief (about one page) narratives by primary and secondary teachers arising from STELLA (Standards for Teachers of English Language and Literacy in Australia) workshops and interpretive discussions. Notes that each narrative describes a moment of "good" English/literacy teaching. (SG)

  2. An Interview with Stella Adler.

    ERIC Educational Resources Information Center

    Rotte, Joanna

    2002-01-01

    Details the life of Stella Adler, an actor, director, and teacher who studied with Stanislavsky. Includes an interview (conducted in 1974) which touches on her influences, teachers, theatre groups, and styles of acting. (PM)

  3. Stella: Independence through Education.

    ERIC Educational Resources Information Center

    Danker, Cherry B.

    1993-01-01

    The author reminisces about her aunt Stella Bolstridge (1894-1989), who came from a large poor family in rural Maine, yet completed high school and nurses' training, served as an Army nurse in France during World War I, and became a lifelong advocate of women's education and women's rights. (SV)

  4. STELLA: 10 years of robotic observations on Tenerife

    NASA Astrophysics Data System (ADS)

    Weber, Michael; Granzer, Thomas; Strassmeier, Klaus G.

    2016-07-01

    STELLA is a robotic observatory on Tenerife housing two 1.2m robotic telescopes. One telescope is fibre-feeding a high-resolution (R=55,000) échelle spectrograph (SES), while the other telescope is equipped with a visible wide- field (FOV=22' x 22') imaging instrument (WiFSIP). Robotic observations started mid 2006, and the primary scientific driver is monitoring of stellar-activity related phenomena. The STELLA Control System (SCS) software package was originally tailored to the STELLA roll-off style building and high-resolution spectroscopy, but was extended over the years to support the wide-field imager, an off-axis guider for the imager, separate acquisition telescopes, classical domes, and targets-of-opportunity. The SCS allows for unattended, off-line operation of the observatory, targets can be uploaded at any time and are selected based on merit-functions in real-time (dispatch scheduling). We report on the current status of the observatory and the current capabilities of the SCS.

  5. APPLICATION OF SUSTAINABILITY CRITERIA TO STELLA, MISSOURI-GENERAL BACKGROUND ON STELLA, MISSOURI-16NOV2006 (0845-0915)

    EPA Science Inventory

    The history of Stella, Missouri and the contaminated/deteriorated Cardwell Hospital is provided as background to planning and revitalization of the site and how it has driven the town to reconsider its future. The use of maps, photos, and a process of eliciting community values p...

  6. STELLA Supplements Superior Standards in School!

    ERIC Educational Resources Information Center

    Andrew, Amy

    2009-01-01

    Known as the "STELLA" (Standards for Teachers of English Language & Literacy in Australia) Standards Framework, there are a set of nine principles which all teachers of English in Australia should aspire to weave into their professional teaching practices. This article describes the journey that Miss Amy Andrew had embarked on in…

  7. Beyond Externalising and Finalising Definitions: Standards for Teachers of English Language and Literacy in Australia (STELLA)

    ERIC Educational Resources Information Center

    Doecke, Brenton

    2007-01-01

    This article explores issues relating to the development of the Standards for Teachers of English Language and Literacy in Australia (STELLA). STELLA is the product of work by members of the Australian Association for the Teaching of English (AATE) and the Australian Literacy Educators' Association (ALEA), the two key professional bodies in…

  8. Baldovin-Stella stochastic volatility process and Wiener process mixtures

    NASA Astrophysics Data System (ADS)

    Peirano, P. P.; Challet, D.

    2012-08-01

    Starting from inhomogeneous time scaling and linear decorrelation between successive price returns, Baldovin and Stella recently proposed a powerful and consistent way to build a model describing the time evolution of a financial index. We first make it fully explicit by using Student distributions instead of power law-truncated Lévy distributions and show that the analytic tractability of the model extends to the larger class of symmetric generalized hyperbolic distributions and provide a full computation of their multivariate characteristic functions; more generally, we show that the stochastic processes arising in this framework are representable as mixtures of Wiener processes. The basic Baldovin and Stella model, while mimicking well volatility relaxation phenomena such as the Omori law, fails to reproduce other stylized facts such as the leverage effect or some time reversal asymmetries. We discuss how to modify the dynamics of this process in order to reproduce real data more accurately.

  9. Using STELLA Simulation Models to Teach Natural Resource Economics

    ERIC Educational Resources Information Center

    Dissanayake, Sahan T. M.

    2016-01-01

    In this article, the author discusses how graphical simulation models created using STELLA software can be used to present natural resource systems in an intuitive way in undergraduate natural resource economics classes based on his experiences at a leading research university, a state university, and a leading liberal arts college in the United…

  10. Co-existence of Endometriotic Cyst of the Ovary and Arias-Stella Reaction in a Non-Pregnant Woman: Report of a Rare Case.

    PubMed

    Harikrishnan, Volga; Esaki, Muthuvel; Srinivasan, Chitra; Arockiasamy, Parimala; Ethirajan, Shanthi

    2016-03-01

    Endometriosis is defined as presence of endometrial tissue outside the uterus. It can occur anywhere in the ovary. In the ovary it is usually presented as cyst, termed as endometriotic cyst or Chocolate cyst. Arias-Stella reaction is usually seen in gestational endometrium or in ectopic gestation site and rarely in non-pregnant uterus with hormonal intake. Co-existence of endometriosis and Arias-Stella reaction is very rare. We present a very rare case of endometriotic cyst of the ovary exhibiting Arias -Stella reaction which was seen in of non pregnant patient without any history of hormonal intake.

  11. Sub-barrier fusion cross section measurements with STELLA

    NASA Astrophysics Data System (ADS)

    Heine, M.; Courtin, S.; Fruet, G.; Jenkins, D. G.; Montanari, D.; Adsley, P.; Beck, C.; Della Negra, S.; Dené, P.; Haas, F.; Hammache, F.; Heitz, G.; Kirsebom, O. S.; Krauth, M.; Lesrel, J.; Meyer, A.; Morris, L.; Regan, P. H.; Richer, M.; Rudigier, M.; de Séréville, N.; Stodel, C.

    2018-01-01

    The experimental setup STELLA (STELlar LAboratory) is designed for the measurement of deep sub-barrier light heavy ion fusion cross sections. For background suppression the γ-particle coincidence technique is used. In this project, LaBr3 detectors from the UK FATIMA (FAst TIMing Array) collaboration are combined with annular silicon strip detectors customized at IPHC-CNRS, Strasbourg, and the setup is located at Andromède, IPN, Orsay. The commissioning of the experimental approach as well as a sub-barrier 12C +12C → 24Mg∗ cross section measurement campaign are carried out.

  12. Whither/Wither STELLA? A Sea Change, or a Bureaucratic Chore? A Victorian Perspective

    ERIC Educational Resources Information Center

    Hayes, Terry

    2007-01-01

    Readers of "English in Australia" are well aware of the genesis and development of Standards for Teachers of English Language and Literacy in Australia (STELLA), since its evolution has been extensively documented in this journal, beginning in 1999 with Margaret Gill's call to arms to the profession, "If we don't do it someone else…

  13. Sustainable Community Case Study: An Assessment of EPA’s Sustainable Development Plan for Stella, Missouri

    EPA Science Inventory

    In 2006, citizens of Stella, Missouri asked the EPA for technical assistance in demolition and site remediation of an abandoned hospital; and how to redevelop the site to help the community be more sustainable. EPA Region 7 teamed with EPA Office of Research and Development (ORD...

  14. Using STELLA System Dynamic Model to Analyze Greenhouse Gases' Emission From Solid Waste Management in Taiwan

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

    Horng, Jao-Jia; Lee, R.F.; Liao, K.Y.

    2004-03-31

    Using a system dynamic model (SDM), such as STELLA, to analyze the waste management policy is a new trial for Taiwan's research communities. We have developed an easy and relatively accurate model for analyzing the greenhouse gases emission for the wastes from animal farming and municipalities. With the local research data of the past decade, we extract the most prominent factors and assemble the SDM. The results and scenarios were compared with the national inventory. By comparing to the past data, we found these models reasonably represent the situation in Taiwan. However, SDM can program many scenarios and produce amore » lot of prediction data. With the development of many program control tools on STELLA, we believe the models could be further used by researchers or policy-makers to find the needed research topics, to set the future scenarios and to determine the management tools.« less

  15. Contribution of Starlette, Stella, and AJISAI to the SLR-derived global reference frame

    NASA Astrophysics Data System (ADS)

    Sośnica, Krzysztof; Jäggi, Adrian; Thaller, Daniela; Beutler, Gerhard; Dach, Rolf

    2014-08-01

    The contribution of Starlette, Stella, and AJISAI is currently neglected when defining the International Terrestrial Reference Frame, despite a long time series of precise SLR observations and a huge amount of available data. The inferior accuracy of the orbits of low orbiting geodetic satellites is the main reason for this neglect. The Analysis Centers of the International Laser Ranging Service (ILRS ACs) do, however, consider including low orbiting geodetic satellites for deriving the standard ILRS products based on LAGEOS and Etalon satellites, instead of the sparsely observed, and thus, virtually negligible Etalons. We process ten years of SLR observations to Starlette, Stella, AJISAI, and LAGEOS and we assess the impact of these Low Earth Orbiting (LEO) SLR satellites on the SLR-derived parameters. We study different orbit parameterizations, in particular different arc lengths and the impact of pseudo-stochastic pulses and dynamical orbit parameters on the quality of the solutions. We found that the repeatability of the East and North components of station coordinates, the quality of polar coordinates, and the scale estimates of the reference are improved when combining LAGEOS with low orbiting SLR satellites. In the multi-SLR solutions, the scale and the component of geocenter coordinates are less affected by deficiencies in solar radiation pressure modeling than in the LAGEOS-1/2 solutions, due to substantially reduced correlations between the geocenter coordinate and empirical orbit parameters. Eventually, we found that the standard values of Center-of-mass corrections (CoM) for geodetic LEO satellites are not valid for the currently operating SLR systems. The variations of station-dependent differential range biases reach 52 and 25 mm for AJISAI and Starlette/Stella, respectively, which is why estimating station-dependent range biases or using station-dependent CoM, instead of one value for all SLR stations, is strongly recommended. This clearly indicates

  16. From the Outside In: Getting Physical with Exercises Inspired by Stella Adler and Uta Hagen.

    ERIC Educational Resources Information Center

    Miller, Bruce

    2002-01-01

    Proposes that teaching students to find and play appropriate actions helps them tell the story of a play and create character better than if they focused on emotions. Discusses Stella Adler and Uta Hagen, two acting teachers who advocated this physical approach. Presents two exercises: "justify and connect," and "enter a room." (PM)

  17. An electron momentum spectroscopy and density functional theory study of the outer valence electronic structure of stella-2,6-dione

    NASA Astrophysics Data System (ADS)

    Nixon, K. L.; Wang, F.; Campbell, L.; Maddern, T.; Winkler, D.; Gleiter, R.; Loeb, P.; Weigold, E.; Brunger, M. J.

    2003-07-01

    We report on the first electron momentum spectroscopy (EMS) study into the outer valence electronic structure of the ground electronic state for the organic molecule stella-2,6-dione (C8H8O2). Experimentally measured binding-energy spectra are compared against a He(Ialpha) photoelectron spectroscopy result, while our derived momentum distributions (MDs) are compared against corresponding results from the plane wave impulse approximation (PWIA) level calculations. These computations employed density functional theory (DFT) basis states at the triple zeta valence polarization (TZVP) level, with a range of exchange-correlation (XC) functionals. A detailed comparison between the experimental and PWIA DFT-XC/TZVP calculated MDs enabled us to evaluate the accuracy of the various functionals, the Becke-Perdew (BP) XC functional being found to provide the most accurate description here. The importance of the through-bond interaction to the molecular orbitals (MOs) of stella-2,6-dione is demonstrated using the orbital imaging capability of EMS. Finally we show that the molecular geometry of this molecule, as derived from BP/TZVP, is in quite good agreement with corresponding independent experimental data.

  18. APPLICATION OF SUSTAINABILITY CRITERIA TO STELLA, MISSOURI-SOCIAL PLANNING-PRELIMINARY SITE INFORMATION AND ELEMENTS OF THE MASTER PLAN-16NOV2006 (0915-0930)

    EPA Science Inventory

    Social systems constraints and performance requirements that are essential to society in general form a list of criteria for planning a sustainable society. This presentation places these social criteria in the context of Stella, Missouri so that workshop participants can provide...

  19. Prevention and Early Intervention: Individual Differences as Risk Factors for the Mental Health of Children. A Festschrift for Stella Chess and Alexander Thomas.

    ERIC Educational Resources Information Center

    Carey, William B., Ed.; McDevitt, Sean C., Ed.

    This collection of essays, in honor of child psychiatry pioneers Stella Chess and Alexander Thomas, focuses on their idea that important life outcomes are the product of ongoing interactions between a child's behavioral style and the complimentarity or lack of fit of the parenting environment. Following an introduction, the remaining chapters are:…

  20. Societal trends, mobility behaviour and sustainable transport in Europe and North America: the European Union network STELLA.

    PubMed

    Rudinger, Georg; Donaghy, Kieran; Poppelreuter, Stefan

    2004-12-01

    This contribution introduces the work of the European Union network Sustainable Transport in Europe and Links and Liaisons to America (STELLA) in the first section and examines especially social and behavioural aspects of sustainable transport from a transatlantic perspective in the second section. One of the most significant societal trends, the ageing of societies, is surveyed and its implications for mobility behaviour are shown. The sustainability of this behaviour is considered along with constraints and drivers of this behaviour in Europe and North America. The contribution takes up relevant policy issues and concludes with a discussion of a transatlantic research agenda on social and behavioural aspects of sustainable transport especially concerning the elderly.

  1. Safety and efficacy of ipragliflozin in Japanese patients with type 2 diabetes in real-world clinical practice: interim results of the STELLA-LONG TERM post-marketing surveillance study.

    PubMed

    Nakamura, Ichiro; Maegawa, Hiroshi; Tobe, Kazuyuki; Tabuchi, Hiromi; Uno, Satoshi

    2018-02-01

    Data regarding the efficacy and safety of sodium-glucose cotransporter 2 inhibitors in the real-world setting in Japan are limited. The STELLA-LONG TERM study is an ongoing 3-year post-marketing surveillance study of ipragliflozin in type 2 diabetes (T2D) patients. Here, we report the interim results (including 3-, 12-, and 24-month data). All Japanese patients with T2D who were first prescribed ipragliflozin between 17 July 2014 and 16 October 2015 at participating centers in Japan were registered in STELLA-LONG TERM. At 3, 12, and 24 months, the safety analysis set comprised 11,053, 5475, and 138 patients, respectively; the efficacy analysis set comprised 8757 patients. Ipragliflozin treatment resulted in statistically significant improvements versus baseline in hemoglobin A1c, fasting plasma glucose concentration, body weight, blood pressure, heart rate, and serum concentrations of low-density lipoprotein cholesterol and triglycerides. The adverse drug reaction incidence rate was 10.71%, the most common reactions being renal and urinary disorders (5.06%), infections and infestations (1.24%), and skin and subcutaneous tissue disorders (1.14%). Ipragliflozin was well tolerated and effective in Japanese patients with T2D; no new safety issues were identified.

  2. Safety and efficacy of ipragliflozin in elderly versus non-elderly Japanese patients with type 2 diabetes mellitus: a subgroup analysis of the STELLA-LONG TERM study.

    PubMed

    Maegawa, Hiroshi; Tobe, Kazuyuki; Tabuchi, Hiromi; Nakamura, Ichiro; Uno, Satoshi

    2018-03-01

    This subgroup analysis of STELLA-LONG TERM interim data explored the long-term safety and efficacy of ipragliflozin in non-elderly vs. elderly Japanese type 2 diabetes mellitus (T2DM) patients. STELLA-LONG TERM is an ongoing 3-year prospective surveillance study of Japanese T2DM patients receiving ipragliflozin 50 mg once daily. In this subgroup analysis, patient characteristics, laboratory variables, and adverse drug reactions (ADRs) were compared between non-elderly (<65 years) and elderly (≥65 years) patients. Non-elderly patients had significantly higher body mass index and low-density lipoprotein cholesterol than elderly patients (P < 0.001). The proportion of patients with hemoglobin A1c (HbA1c) <8.0% was significantly higher among elderly patients (P < 0.001). HbA1c, fasting plasma glucose, and body weight significantly decreased from baseline to 3 and 12 months in both groups (all P < 0.05 vs. baseline). The ADR incidence was 10.83% vs. 10.42% in non-elderly and elderly patients. The incidence of skin complications was 0.98% vs. 1.65% and that of renal disorder was 0.47% vs. 0.95% in non-elderly and elderly patients (both P = 0.003). Ipragliflozin was effective in non-elderly and elderly Japanese T2DM patients in a real-world clinical setting. The incidence of renal disorder and skin complications was significantly higher in elderly vs. non-elderly patients.

  3. Who Loves Prescriptivism and Why? Some Aspects of Language Correctness in Latvia

    ERIC Educational Resources Information Center

    Strelevica-Ošina, Dace

    2016-01-01

    Taking into account the crosscultural differences in prescriptive attitudes in various linguistic communities, a theory of three types of prescriptivism--human-oriented, language-oriented, and error-oriented prescriptivism--has been offered [Strelevica-Ošina, Dace. [2011] 2012. "Kapec mes gribam, lai valoda ir pareiza? Ieskats preskriptivisma…

  4. CHARGE TO WORKSHOP PARTICIPANTS - 11/16/06

    EPA Science Inventory

    The focus of this workshop will be developed a Master Revitalization Plan for the community of Stella, Missouri. Stella is anticipating growth pressure from Benton County, Arkansas. Although growth is desired to recreate a viable local economy and social programs, citizens are co...

  5. Storylines of socio-economic and climatic drivers for land use and their hydrological impacts in alpine catchments - the STELLA project example

    NASA Astrophysics Data System (ADS)

    Strasser, Ulrich; Formayer, Herbert; Förster, Kristian; Marke, Thomas; Meißl, Gertraud; Schermer, Markus; Stotten, Friederike; Themessl, Matthias

    2016-04-01

    Future land use in Alpine catchments is controlled by the evolution of socio-economy and climate. Estimates of their coupled development should hence fulfill the principles of plausibility (be convincing) and consistency (be unambiguous). In the project STELLA, coupled future climate and land use scenarios are used as input in a hydrological modelling exercise with the physically-based, distributed water balance model WaSiM. The aim of the project is to quantify the effects of these two framing components on the future water cycle. The test site for the simulations is the catchment of the Brixentaler Ache in Tyrol/Austria (47.5°N, 322 km2). The so-called „storylines" of future coupled climate and forest/land use management, policy, social cooperation, tourism and economy have jointly been developed in an inter- and transdisciplinary assessment with local actors. The climate background is given by simulations for the A1B (temperature conditions like today in Merano/Italy, 46.7°N) and RCP 8.5 (temperature conditions like today in Bologna/Italy, 44.5°N) emission scenarios. These two climate scenarios were combined with three potential socio-economic developments („local"/„glocal"/ „superglobal"), each in a positive and in a negative specification. From these twelve storylines of coupled climate/land use future, a set of four storylines was selected to be used in transient hydrological modelling experiments. Historical simulations of the water balance for the test site reveal the pattern of land use being the most prominent factor for the spatial distribution of its components. A new prototype for a snow-canopy interaction simulation module provides explicit rates of intercepted and sublimated snow from the trees and stems of the different forest stands in the catchment. This new canopy module will be used to model the coupled climate/land use future storylines for the Brixental. The aim is to quantify the effects of climate change and land use on the water

  6. 75 FR 3939 - Merit Systems Protection Board (MSPB) Provides Notice of Opportunity To File Amicus Briefs

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-25

    ... the opportunity to file amicus briefs in the matter of Stella Crumpler v. Department of Defense, MSPB... be captioned ``Stella Crumpler v. Department of Defense'' and entitled ``Amicus Brief.'' Only one... CFR Part 732, National Security Position, the rule in Department of the Navy v. Egan, 484 U.S. 518...

  7. A role for Lin28 in primordial germ cell development and germ cell malignancy

    PubMed Central

    West, Jason A.; Viswanathan, Srinivas R.; Yabuuchi, Akiko; Cunniff, Kerianne; Takeuchi, Ayumu; Park, In-Hyun; Sero, Julia E.; Zhu, Hao; Perez-Atayde, Antonio; Frazier, A. Lindsay; Surani, M. Azim; Daley, George Q.

    2009-01-01

    The rarity and inaccessibility of the earliest primordial germ cells (PGCs) in the mouse embryo thwarts efforts to investigate molecular mechanisms of germ cell specification. Stella marks the minute founder population of the germ lineage1,2. Here we differentiate mouse embryonic stem cells (ESCs) carrying a Stella transgenic reporter into putative PGCs in vitro. The Stella+ cells possess a transcriptional profile similar to embryo-derived PGCs, and like their counterparts in vivo, lose imprints in a time-dependent manner. Using inhibitory RNAs to screen candidate genes for effects on the development of Stella+ cells in vitro, we discovered that Lin28, a negative regulator of let-7 microRNA processing3-6, is essential for proper PGC development. We further show that Blimp1, a let-7 target and a master regulator of PGC specification7-9, can rescue the effect of Lin28-deficiency during PGC development, thereby establishing a mechanism of action for Lin28 during PGC specification. Over-expression of Lin28 promotes formation of Stella+ cells in vitro and PGCs in chimeric embryos, and is associated with human germ cell tumours. The differentiation of putative PGCs from ESCs in vitro recapitulates the early stages of gamete development in vivo, and provides an accessible system for discovering novel genes involved in germ cell development and malignancy. PMID:19578360

  8. More STELLA Narratives.

    ERIC Educational Resources Information Center

    English in Australia, 2001

    2001-01-01

    Presents brief essays by teachers of English in Australian primary and secondary schools in a bid to convey images of accomplished teaching. Introduction by Brenton Doecke, includes "Negotiating the Curriculum" (Lynne Collidge); "Year 7 Autobiographies" (Chris Melican); "Taking Ownership" (Cheryl Lawson);…

  9. Drag Coefficient Estimation in Orbit Determination

    NASA Astrophysics Data System (ADS)

    McLaughlin, Craig A.; Manee, Steve; Lichtenberg, Travis

    2011-07-01

    Drag modeling is the greatest uncertainty in the dynamics of low Earth satellite orbits where ballistic coefficient and density errors dominate drag errors. This paper examines fitted drag coefficients found as part of a precision orbit determination process for Stella, Starlette, and the GEOSAT Follow-On satellites from 2000 to 2005. The drag coefficients for the spherical Stella and Starlette satellites are assumed to be highly correlated with density model error. The results using MSIS-86, NRLMSISE-00, and NRLMSISE-00 with dynamic calibration of the atmosphere (DCA) density corrections are compared. The DCA corrections were formulated for altitudes of 200-600 km and are found to be inappropriate when applied at 800 km. The yearly mean fitted drag coefficients are calculated for each satellite for each year studied. The yearly mean drag coefficients are higher for Starlette than Stella, where Starlette is at a higher altitude. The yearly mean fitted drag coefficients for all three satellites decrease as solar activity decreases after solar maximum.

  10. A multi-proxy paleolimnological reconstruction of Holocene climate conditions in the Great Basin, United States

    NASA Astrophysics Data System (ADS)

    Reinemann, Scott A.; Porinchu, David F.; Bloom, Amy M.; Mark, Bryan G.; Box, Jason E.

    2009-11-01

    A sediment core spanning ˜ 7000 cal yr BP recovered from Stella Lake, a small sub-alpine lake located in Great Basin National Park, Nevada, was analyzed for subfossil chironomids (non-biting midges), diatoms, and organic content (estimated by loss-on-ignition (LOI)). Subfossil chironomid analysis indicates that Stella Lake was characterized by a warm, middle Holocene, followed by a cool "Neoglacial" period, with the last two millennia characterized by a return to warmer conditions. Throughout the majority of the core the Stella Lake diatom-community composition is dominated by small, periphytic taxa which are suggestive of shallow, cool, alkaline, oligotrophic waters with extensive seasonal ice cover. A reconstruction of mean July air temperature (MJAT) was developed by applying a midge-based inference model for MJAT (two-component WA-PLS) consisting of 79 lakes and 54 midge taxa ( rjack2 = 0.55, RMSEP = 0.9°C). Comparison of the chironomid-inferred temperature record to existing regional paleoclimate reconstructions suggests that the midge-inferred temperatures correspond well to regional patterns. This multi-proxy record provides valuable insight into regional Holocene climate and environmental conditions by providing a quantitative reconstruction of peak Holocene warmth and aquatic ecosystem response to these changes in the Great Basin, a region projected to experience increased aridity and higher temperatures.

  11. FINAL MASTER PLAN FOR STELLA, MISSOURI

    EPA Science Inventory

    The application of sustainability to place is the outcome of responding to human needs and expectations within economic, social, and environmental constraints and desired performance of these systems. These constraints and performance requirements of these systems provides a way ...

  12. Johannes Kepler on Christmas

    NASA Astrophysics Data System (ADS)

    Kemp, Martin

    2009-12-01

    Kepler's interpretation of the supernova of 1604, De Stella Nova, interwove the science of astronomy with astrology and theology in an attempt to determine the correct birthdate of Jesus, explains Martin Kemp.

  13. Effect of Ocean Tide Models on the Precise Orbit Determination of Geodetic Satellites

    NASA Astrophysics Data System (ADS)

    Kubo-Oka, T.; Matsumoto, K.; Otsubo, T.; Gotoh, T.

    2005-12-01

    Several ocean tide models are tested with precise observation data of satellite laser ranging to geodetic satellites, Starlette and Stella. Four ocean models, NAO.99b, CSR 3.0 (standard model in IERS Conventions 2003), CSR 4.0, and GOT99.2b were implemented in our orbit analysis software "concerto ver. 4". NAO.99b model was developed by assimilating tidal solutions from TOPEX/POSEIDON altimeter data into hydrodynamical model. Eight constituents (M2, S2, K1, O1, N2, P1, K2, Q1) were taken into account in each ocean tide model. Moreover, eight additional constituents (M1, J1, OO1, 2N2, Mu2, Nu2, L2, T2) can be included in NAO.99b model. Effect of ocean tides on geopotential coefficients were computed to 20th order. SLR data to Starlette and Stella were divided into arcs of 7 days length and 52 arcs (Jan. 2 - Dec. 30, 2004) were analyzed. Using different ocean tide model, orbits of these satellites were determined and weighted rms of postfit residuals are compared. We found that the NAO.99b model with 16 constituents can reduce weighted rms of postfit residuals using to the level of about 6.0 cm (Starlette) and 9.6 cm (Stella). These values are about 3-5 % smaller compared to other ocean tide models.

  14. Four inches and seven pounds | NIH MedlinePlus the Magazine

    MedlinePlus

    ... faces in managing the disease is guarding Stella's food from contamination. "Even a crumb of wheat is critical to her health," says Maghann. "So we bought a new toaster, for example. But it's ... food, being especially vigilant about sourcing ingredients from "gluten- ...

  15. Simulating phosphorus removal from a vertical-flow constructed wetland grown with C. alternifolius species

    USDA-ARS?s Scientific Manuscript database

    Vertical flow constructed wetland (VFCW) is a promising engineering technique for removal of excess nutrients and certain pollutants from wastewater and stormwater. The aim of this study was to develop a STELLA (Structural Thinking, Experiential Learning Laboratory with Animation) model for estimati...

  16. Studies in Teaching. 1996 Research Digest.

    ERIC Educational Resources Information Center

    McCoy, Leah P., Ed.

    The 19 papers presented at Wake Forest University's 1996 Annual Research Forum (Winston-Salem, North Carolina) are as follows: "Initiating and Facilitating Discourse: An Examination of Methods of Four Secondary English Classrooms" (Stella Katherine Beale); "Cheating: Beliefs and Habits" (William Clark); "English…

  17. Decidual vascular changes in early pregnancy as a marker for intrauterine pregnancy.

    PubMed

    Lichtig, C; Korat, A; Deutch, M; Brandes, J M

    1988-09-01

    Endometrial vascular changes similar to atherosclerosis of toxemia of pregnancy were described and graded in 217 consecutive endometrial biopsies of known early intrauterine pregnancy. Severe vascular changes were found in 23.5% of cases. Control material consisting of endometrial biopsies of patients with known cases of tubal ectopic pregnancy and various non-pregnancy menstrual disorders showed minimal or no changes except in one case. A parallel study of Aria-Stella phenomenon in 110 cases of uterine pregnancy showed significant changes in only 3.6% of patients. It is obvious that in these cases of positive Arias-Stella findings, the possibility of an extrauterine pregnancy could not be discarded on histologic grounds alone. The authors suggest the use of the vascular changes of the more severe histologic degree as described in this article as a positive or strongly suspicious marker for intrauterine pregnancy whenever this is needed.

  18. Exploring Ancient Civilizations in the Eastern Mediterranean.

    ERIC Educational Resources Information Center

    Lehrer, Stanley; Shapiro, Melanie

    1984-01-01

    Several nations can be explored within one week by sailing on the Stella Solarus to Egypt, Israel, Rhodes, and Turkey. The stop in Egypt includes visits to Cairo and the Pyramids at Giza, while the Israeli tour includes trips to Jerusalem and Haifa. (CS)

  19. Setting Standards: Confronting Paradox.

    ERIC Educational Resources Information Center

    Doecke, Brenton; Gill, Margaret

    2001-01-01

    Discusses implications of the issues of continuity and discontinuity, commonality and difference, congruity and paradox as they engage the research team, the industry partners, and the teachers around Australia who constitute the STELLA (Standards for Teachers of English Language and Literacy in Australia) project. (RS)

  20. Temperament and School Learning. Papers presented at a Symposium at the Annual Meeting of the American Educational Research Association (68th, New Orleans, LA, April 23-27, 1984).

    ERIC Educational Resources Information Center

    Wang, Margaret C., Ed.

    Four research papers on temperament and school learning and two commentaries are presented. "Early Temperament and Later Educational Outcomes," by Jacqueline V. Lerner, Stella Chess, and Kathleen Lenerz, discusses temperament characteristics and academic attainment. One hundred thirty-three middle class subjects were studied from early infancy…

  1. Enacting a Critical Pedagogy: A View inside an Introduction to Fiction Classroom

    ERIC Educational Resources Information Center

    Scales, Sheryl Diahanna

    2009-01-01

    This is a qualitative instrumental case study that explores the intersections of critical theory, critical pedagogy, and critical literacy. Additionally, it describes the pedagogy of an English graduate assistant, Stella Lane, who taught a freshman-sophomore literature course at a large Midwestern Research I university. This dissertation examines…

  2. Stories: A Common Currency

    ERIC Educational Resources Information Center

    Parr, Graham; Doecke, Brenton; Bulfin, Scott

    2015-01-01

    This article offers an account of a series of writing workshops involving English teachers in Victoria, Australia, known as the "stella2.0" project. It argues that storytelling can potentially provide a valuable counterpoint to the "knowledge" underpinning standards-based reforms. The argument serves to introduce two other…

  3. Visual Sociological Portrayals of Race and Childhood: Case Studies from the Thirties.

    ERIC Educational Resources Information Center

    Wieder, Alan

    1995-01-01

    Describes life during the Depression era by studying narrative and visual portrayals of African American children in both rural and urban settings. Sources include Richard Wright's "12 Million Black Voices" and Stella Gentry Sharpe's "Tobe" as well as work that critically analyzes these narrative and visual documentations of…

  4. The Great Acting Teachers and Their Methods.

    ERIC Educational Resources Information Center

    Brestoff, Richard

    This book explores the acting theories and teaching methods of great teachers of acting--among them, the Europeans Stanislavski, Meyerhold, Brecht, and Grotowski; the Japanese Suzuki (who trained in Europe); and the contemporary Americans, Stella Adler, Lee Strasberg, and Sanford Meisner. Each chapter of the book includes a sample class, which…

  5. Engaging with the Profession: Communities of Learners

    ERIC Educational Resources Information Center

    Meiers, Marion

    2007-01-01

    In 2005 the Australian Literacy Educators' Association (ALEA) established a professional learning project focused on the Standards for Teachers of English Language and Literacy in Australia (STELLA) professional standards developed earlier in the decade by the Australian Association for the Teaching of English (AATE) and ALEA. The key question for…

  6. The Effect of Storytelling and Retelling and Higher Order Thinking on Oral Performance of Elementary Students in English as Foreign Language (EFL) Program: A Pilot Study in Mainland China and Taiwan

    ERIC Educational Resources Information Center

    Yang, Pei-lin; Tong, Fuhui; Irby, Beverly J.; Lara-Alecio, Rafael; Ramos, Norma; Nava-Walichowski, Miranda

    2016-01-01

    The purpose of this pilot study was to evaluate the effect of Story Telling and retelling and higher order thinking for "E"nglish "L"anguage and "L"iteracy "A"cquisition (STELLA) on the English oral proficiency of elementary students in Mainland China and Taiwan, where English is taught as a foreign…

  7. A System Dynamics Model of the Departmental Deployment of Instructional Resources.

    ERIC Educational Resources Information Center

    Beck, Bruce D.

    This paper reports on the development and testing of a system dynamics model of the departmental deployment of instructional resources at the University of Wisconsin-Madison. A model was developed using the Stella II computer software package. The model describes describes how departments keep student enrollments, number of course sections, and…

  8. Computer-Assisted Community Planning and Decision Making.

    ERIC Educational Resources Information Center

    College of the Atlantic, Bar Harbor, ME.

    The College of the Atlantic (COA) developed a broad-based, interdisciplinary curriculum in ecological policy and community planning and decision-making that incorporates two primary computer-based tools: ARC/INFO Geographic Information System (GIS) and STELLA, a systems-dynamics modeling tool. Students learn how to use and apply these tools…

  9. A Paediatrician Looks at Traditional Approaches to Emotional Development in Preschool and Primary Years. Foundation for Child and Youth Studies Selected Papers Number 46.

    ERIC Educational Resources Information Center

    Phillips, Susi Erika

    This discussion of the emotional development of young children is structured upon Erik Erikson's schemata of psycho-social development. Stage 1, which involves trust versus mistrust, includes references to Erikson's theory and the work of Melanie Klein, Berry Brazelton, Stella Chess and Alexander Thomas, John Bowlby, Anthony Stevens, and D. W.…

  10. "Speak Out. Act Up. Move Forward." Disobedience-Based Arts Education

    ERIC Educational Resources Information Center

    Kotin, Alison; Aguirre McGregor, Stella; Pellecchia, DeAnna; Schatz, Ingrid; Liu, Shaw Pong

    2013-01-01

    In this essay, Alison Kotin, Stella Aguirre McGregor, DeAnna Pellecchia, Ingrid Schatz, and Shaw Pong Liu reflect on their experiences working with public high school students to create "Speak Out. Act Up. Move Forward.," a performative response to current and historical acts of civil disobedience. The authors--a group of instructors…

  11. Transformation & Metamorphosis

    ERIC Educational Resources Information Center

    Lott, Debra

    2009-01-01

    The sculptures of Canadian artist Brian Jungen are a great inspiration for a lesson on creating new forms. Jungen transforms found objects into unique creations without fully concealing their original form or purpose. Frank Stella's sculpture series, including "K.132,2007" made of stainless steel and spray paint, is another great example of…

  12. Higher Education and Children in Immigrant Families

    ERIC Educational Resources Information Center

    Baum, Sandy; Flores, Stella M.

    2011-01-01

    The increasing role that immigrants and their children, especially those from Latin America, are playing in American society, Sandy Baum and Stella Flores argue, makes it essential that as many young newcomers as possible enroll and succeed in postsecondary education. Immigrant youths from some countries find the doors to the nation's colleges…

  13. The Systems Thinking and Curriculum Innovation Project. Technical Report, Part 2.

    ERIC Educational Resources Information Center

    Mandinach, Ellen B.; Thorpe, Margaret E.

    This is the second of two reports on the first year activities and results of the Systems Thinking and Curriculum Innovation Project (STACI), a two-year project which is examining the cognitive demands and consequences of using the STELLA (Structural Thinking Experimental Learning Laboratory with Animation) software to teach systems thinking,…

  14. La Stella di Betlemme in arte e scienza

    NASA Astrophysics Data System (ADS)

    Sigismondi, Costantino

    2014-05-01

    The star of Bethlehem has been represented in many artworks, starting from II century AD in Priscilla Catacumbs in Rome. The 14 pointed silver star of 1717 which is located in the place of birth of Jesus in Bethlehem remembers the numbers of generations 14 repeated three times since Abraham to Jesus in Matthew 1: 1-17. Finally the hypotehsis of Mira Ceti as star of Bethlehem is reviewed

  15. Planning Sustainability: A Master Plan For Stella, Missouri

    EPA Science Inventory

    Human Life is conditional upon intact ecosystems that provide goods and services required to sustain human life. Because development will incrementally and cumulative consume the biophysical environment, the conditions of intact ecosystems must be the basis for how the environme...

  16. Simulating phosphorus removal from a vertical-flow constructed wetland grown with C alternifolius species

    Treesearch

    Ying Ouyang; Lihua Cui; Gary Feng; John Read

    2015-01-01

    Vertical flow constructed wetland (VFCW) is a promising technique for removal of excess nutrients and certain pollutants from wastewaters. The aim of this study was to develop a STELLA (structural thinking, experiential learning laboratory with animation) model for estimating phosphorus (P) removal in an artificial VFCW (i.e., a substrate column with six zones) grown...

  17. Breaking into Public Policy Circles for the Benefit of Underserved Communities

    ERIC Educational Resources Information Center

    Flores, Stella M.

    2017-01-01

    Stella M. Flores writes about how she learned to participate in the American political process through lessons from her immigrant family. As a quantitative scholar, she documents the commitment to rigorous, evidence-based research on equity noting that not all datasets are without politics or bias. From this perspective, the story of the Latino in…

  18. Fabricius, David (1564-1617) and Fabricius, Johannes (1587-1616)

    NASA Astrophysics Data System (ADS)

    Murdin, P.

    2000-11-01

    Lutheran pastor and astronomer in Osteel, East Frisia (northwest Germany), discoverer (1596) of the first known variable star, mira stella (`wonderful star'), now simply Mira (Omicron Ceti). Fabricius observed the star at its brightest and thought it was a nova, after which Holwarda noticed that a star in Cetus cataloged by PTOLEMY and TYCHO was missing but then it reappeared. Eventually the long...

  19. Saguaro: A Distributed Operating System Based on Pools of Servers.

    DTIC Science & Technology

    1988-03-25

    asynchronous message passing, multicast, and semaphores are supported. We have found this flexibility to be very useful for distributed programming. The...variety of communication primitives provided by SR has facilitated the research of Stella Atkins, who was a visiting professor at Arizona during Spring...data bits in a raw communication channel to help keep the source and destination synchronized , Psync explicitly embeds timing information drawn from the

  20. Distribution and Taxonomy of Zooplankton in the Alboran Sea and Adjacent Western Mediterranean: A Literature Survey and Field Guide

    DTIC Science & Technology

    1991-09-01

    Distribution List for Technical Report Exchange I Attn: Stella Sanchez-Wade Pell Marine Science Library Documents Section University of Rhode IslandU...partly on the geographic distribution of marine laboratories on the coasts of these seas. Upwelling regions near Messina, Naples and Nice in the...into three main sections . The first considers gjneral patterns of zooplankton distribution. This is intended as an overview of hydrography, zooplankton

  1. Planning Sustainable Land-Use: The Experience Of Stella, Missouri

    EPA Science Inventory

    Sustainability has numerous definitions and is often discussed. However, there are fewer lessons derived from its application. The concept for its application evolved out of a study to determine whether brownfields could be redeveloped to be more environmentally friendly. The ...

  2. Toward Sustainable Land-Use: The Planning of Stella, Missouri

    EPA Science Inventory

    Human life relies upon goods and services that ecosystems provide. If we want these systems to sustain future generations, the limitation to how much of the environment can be consumed to meet human needs is how much must remain to meet human needs. This concept establishes a b...

  3. AF Security Forces and Building Partner Capacity Examining Cultural Competency as a Force Enabler

    DTIC Science & Technology

    2017-02-03

    key leaders taking on these missions across any foreign culture. The concept of “cultural mindfulness ” alone would be a prudent tool to any BPC...team member executing key leader engagements. “ Mindfulness refers to the heightened awareness of our own thinking patterns, affective reactions, and...New York: McGraw Hill. Pp. 5-11. Ting-Toomey, Stella. 1999. “ Mindful Intercultural Verbal Communication.” Communicating Across Cultures. New

  4. Sleep in the Military: Promoting Healthy Sleep Among U.S. Servicemembers

    DTIC Science & Technology

    2015-01-01

    Alfred, Petra E., and Valerie J. Rice, “The Relationship Between Self-Reported Hours of Sleep, Perceptions of Tiredness and Academic Performance in a...A. Martin , Anne M. Sesti, and Karen L. Spritzer, “Psychometric Properties of the Medical Outcomes Study Sleep Measure,” Sleep Medicine, Vol. 6, No. 1...Internal Medicine, Vol. 21, No. 6, 2006, pp. 547–552. Hughes, Jaime, Stella Jouldjian, Donna L. Washington, Cathy A. Alessi, and Jennifer L. Martin

  5. Regulation of Glucose Transport in Quiescent, Lactating, and Neoplastic Mammary Epithelia

    DTIC Science & Technology

    1999-10-01

    accepted subject to minor revision 2. Nemeth, BN, Tsang, ST, Geske , RS, Haney, PM. Golgi targeting of the GLUT1 glucose transporter in lactating mouse...weaning alters glucose transporter targeting in lactating mouse mammary gland. Mol. Biol. Cell 1997; 8, 307a (ASCB poster presentation). 6. Geske , S...Blaise A. Nemeth, Stella W.Y. Tsang, Robert S. Geske , and Peter M. Haney Department of Pediatrics [B.A.N.], University of Wisconsin Children’s Hospital

  6. KOJAK Group Finder: Scalable Group Detection via Integrated Knowledge-Based and Statistical Reasoning

    DTIC Science & Technology

    2006-09-01

    STELLA and PowerLoomn. These modules comunicate with a knowledge basec using KIF and stan(lardl relational database systelnis using either standard...groups ontology as well as a rule that infers additional seed members based on joint participation in a terrorism event. EDB schema files are a special... terrorism links from the Ali Baba EDB. Our interpretation of such links is that they KOJAK Manual E-42 encode that two people committed an act of

  7. STARTING SMALL IN STELLA: LEARNING HOW TO PLAN FOR SUSTAINABILITY

    EPA Science Inventory

    Concepts of sustainability are rarely clearly defined and their applications often seem abstract. Because these concepts must address systems scale, even simple strategies often seem complex, abstract, and overwhelming. The opportunity to apply a theory for sustainable developmen...

  8. Defragged Binary I Ching Genetic Code Chromosomes Compared to Nirenberg’s and Transformed into Rotating 2D Circles and Squares and into a 3D 100% Symmetrical Tetrahedron Coupled to a Functional One to Discern Start From Non-Start Methionines through a Stella Octangula

    PubMed Central

    Castro-Chavez, Fernando

    2012-01-01

    Background Three binary representations of the genetic code according to the ancient I Ching of Fu-Xi will be presented, depending on their defragging capabilities by pairing based on three biochemical properties of the nucleic acids: H-bonds, Purine/Pyrimidine rings, and the Keto-enol/Amino-imino tautomerism, yielding the last pair a 32/32 single-strand self-annealed genetic code and I Ching tables. Methods Our working tool is the ancient binary I Ching's resulting genetic code chromosomes defragged by vertical and by horizontal pairing, reverse engineered into non-binaries of 2D rotating 4×4×4 circles and 8×8 squares and into one 3D 100% symmetrical 16×4 tetrahedron coupled to a functional tetrahedron with apical signaling and central hydrophobicity (codon formula: 4[1(1)+1(3)+1(4)+4(2)]; 5:5, 6:6 in man) forming a stella octangula, and compared to Nirenberg's 16×4 codon table (1965) pairing the first two nucleotides of the 64 codons in axis y. Results One horizontal and one vertical defragging had the start Met at the center. Two, both horizontal and vertical pairings produced two pairs of 2×8×4 genetic code chromosomes naturally arranged (M and I), rearranged by semi-introversion of central purines or pyrimidines (M' and I') and by clustering hydrophobic amino acids; their quasi-identity was disrupted by amino acids with odd codons (Met and Tyr pairing to Ile and TGA Stop); in all instances, the 64-grid 90° rotational ability was restored. Conclusions We defragged three I Ching representations of the genetic code while emphasizing Nirenberg's historical finding. The synthetic genetic code chromosomes obtained reflect the protective strategy of enzymes with a similar function, having both humans and mammals a biased G-C dominance of three H-bonds in the third nucleotide of their most used codons per amino acid, as seen in one chromosome of the i, M and M' genetic codes, while a two H-bond A-T dominance was found in their complementary chromosome, as seen

  9. Papers Selected for Presentation at the International Symposium on Remote Sensing of Environment (16th) Held at Buenos Aires, Argentina on 2-9 June 1982. Volume 2.

    DTIC Science & Technology

    1982-06-01

    ARGENTINA Oscar Dominguez and Stella Carballo .............. 355 STUDIES ON SOME URBAN PROBLEMS USING AIRBORNE REMOTE SENSORS IN SANTIAGO, CHILE ...SAN JUAN ARGENTINA) (1) Silvia Lendaro de Gianni (2,3) Enrique Uliarte (I) Centro Regional de Agua Subterrgnea (2) Universidad Nacional de San Juan act...Hidrogeol6gico para refuerzo do la provisi6n de agua " a Puerto Deseado. In4dito. - Pezzuchi, Hugo Daniel (1978) "studio Geol6gico de la zona de Lstancia Dos

  10. Applying KAM Theory to Highly Eccentric Orbits

    DTIC Science & Technology

    2014-03-27

    Kepler , in 1609, compiled a 650+ page book that dramatically changed the way humans would understand the movement of the heavenly bodies [2]. Though unwit...tingly committing a couple blunders, Kepler published Astronomia Nova ΑΙΤΙΟΛΟΓΣΤΟΣ seu physica coelestis, tradita commentariis de motibus stellae...Martis ex observationibus G.V. Tychonis Brahe, in which he details the arduous process of examining the orbit of Mars. Fortuitously for Kepler , his math

  11. DRAFT MASTER PLAN FOR STELLA, MISSOURI - 20 FEBRUARY 2007, 1900 HOURS

    EPA Science Inventory

    The application of sustainability to place is the outcome of responding to human needs and expectations within economic, social, and environmental constraints and desired performance of these systems. These constraints and performance requirements of these systems provides a way ...

  12. Light Curves of the Type II-P Supernova SN 2017eaw: The First 200 Days

    NASA Astrophysics Data System (ADS)

    Tsvetkov, D. Yu.; Shugarov, S. Yu.; Volkov, I. M.; Pavlyuk, N. N.; Vozyakova, O. V.; Shatsky, N. I.; Nikiforova, A. A.; Troitsky, I. S.; Troitskaya, Yu. V.; Baklanov, P. V.

    2018-05-01

    We present the results of our UBVRI photometry for the type II-P supernova SN 2017eaw in NGC6946 obtained fromMay 14 to December 7, 2017, at several telescopes, including the 2.5-m telescope at the CaucasusHigh-Altitude Observatory of the SAIMSU. The dates andmagnitudes atmaximumlight and the light-curve parameters have been determined. The color evolution, extinction, and peak luminosity of SN 2017eaw are discussed. The results of our preliminary radiation-gasdynamic simulations of its light curves with the STELLA code describe satisfactorily the UBVRI observational data.

  13. System dynamic modeling on construction waste management in Shenzhen, China.

    PubMed

    Tam, Vivian W Y; Li, Jingru; Cai, Hong

    2014-05-01

    This article examines the complexity of construction waste management in Shenzhen, Mainland China. In-depth analysis of waste generation, transportation, recycling, landfill and illegal dumping of various inherent management phases is explored. A system dynamics modeling using Stella model is developed. Effects of landfill charges and also penalties from illegal dumping are also simulated. The results show that the implementation of comprehensive policy on both landfill charges and illegal dumping can effectively control the illegal dumping behavior, and achieve comprehensive construction waste minimization. This article provides important recommendations for effective policy implementation and explores new perspectives for Shenzhen policy makers.

  14. Modeling in the Classroom: An Evolving Learning Tool

    NASA Astrophysics Data System (ADS)

    Few, A. A.; Marlino, M. R.; Low, R.

    2006-12-01

    Among the early programs (early 1990s) focused on teaching Earth System Science were the Global Change Instruction Program (GCIP) funded by NSF through UCAR and the Earth System Science Education Program (ESSE) funded by NASA through USRA. These two programs introduced modeling as a learning tool from the beginning, and they provided workshops, demonstrations and lectures for their participating universities. These programs were aimed at university-level education. Recently, classroom modeling is experiencing a revival of interest. Drs John Snow and Arthur Few conducted two workshops on modeling at the ESSE21 meeting in Fairbanks, Alaska, in August 2005. The Digital Library for Earth System Education (DLESE) at http://www.dlese.org provides web access to STELLA models and tutorials, and UCAR's Education and Outreach (EO) program holds workshops that include training in modeling. An important innovation to the STELLA modeling software by isee systems, http://www.iseesystems.com, called "isee Player" is available as a free download. The Player allows users to view and run STELLA models, change model parameters, share models with colleagues and students, and make working models available on the web. This is important because the expert can create models, and the user can learn how the modeled system works. Another aspect of this innovation is that the educational benefits of modeling concepts can be extended throughout most of the curriculum. The procedure for building a working computer model of an Earth Science System follows this general format: (1) carefully define the question(s) for which you seek the answer(s); (2) identify the interacting system components and inputs contributing to the system's behavior; (3) collect the information and data that will be required to complete the conceptual model; (4) construct a system diagram (graphic) of the system that displays all of system's central questions, components, relationships and required inputs. At this stage

  15. Dischi (E Jet) Nelle Stelle Massicce Giovani

    NASA Astrophysics Data System (ADS)

    Cesaroni, Riccardo

    2017-11-01

    In questo contributo verrà discussa l'importanza dei dischi e jet ad essi asso- ciati per la formazione delle stelle di tipo spettrale OB e verranno presentati i risultati recentemente ottenuti con ALMA in questo ambito. In particolare mostr- eremo che la struttura del disco sembra risentire della complessità dell'ambiente circostante e che la probabilità di rivelare un disco attorno alle stelle di più alta massa è massima in una fase evolutiva intermedia. Infine discuteremo la possibilità che il fenomeno di accrescimento dal disco sulla stella possa avvenire in maniera discontinua mediante "burst", probabilmente dovuti ad instabilità nel disco.

  16. Further X-Ray Observations of EXO 0748-676 in Quiescence: Evidence for a Cooling Neutron Star Crust

    DTIC Science & Technology

    2010-07-01

    Satellite Date ∆t Pow. frac. kT∞eff FX F th bol Lbol Red. χ 2 (days) (%) (eV) (d.o.f.) Swift† 2008-09-28 – 2008-10-07 4.9 10 fix 123.7± 5.4 1.31± 0.22 1.53...fixed. The quoted errors represent 90% confidence levels. FX represents the 0.5–10 keV total model flux and F thbol gives the 0.01–100 keV NSATMOS...Miller J. M., Wijnands R., 2010, submitted to ApJ Campana S., 2003, preprint ( astro -ph/0311212) Campana S., Colpi M., Mereghetti S., Stella L

  17. Considering Environment, Economy, And Society In Land-Use: A Case Study - Stella, Missouri

    EPA Science Inventory

    Human life is conditional upon intact ecosystems that provide goods and services required to sustain human life. Because development will incrementally and cumulative consume the biophysical environment, the conditions of intact ecosystems must be the basis for how the environme...

  18. A Systems Dynamic Model for Drug Abuse and Drug-Related Crime in the Western Cape Province of South Africa

    PubMed Central

    Coetzee, Lezanie

    2017-01-01

    The complex problem of drug abuse and drug-related crimes in communities in the Western Cape province cannot be studied in isolation but through the system they are embedded in. In this paper, a theoretical model to evaluate the syndemic of substance abuse and drug-related crimes within the Western Cape province of South Africa is constructed and explored. The dynamics of drug abuse and drug-related crimes within the Western Cape are simulated using STELLA software. The simulation results are consistent with the data from SACENDU and CrimeStats SA, highlighting the usefulness of such a model in designing and planning interventions to combat substance abuse and its related problems. PMID:28555161

  19. Measurement of low radioactivity background in a high voltage cable by high resolution inductively coupled plasma mass spectrometry

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

    Vacri, M. L. di; Nisi, S.; Balata, M.

    2013-08-08

    The measurement of naturally occurring low level radioactivity background in a high voltage (HV) cable by high resolution inductively coupled plasma mass spectrometry (HR ICP MS) is presented in this work. The measurements were performed at the Chemistry Service of the Gran Sasso National Laboratory. The contributions to the radioactive background coming from the different components of the heterogeneous material were separated. Based on the mass fraction of the cable, the whole contamination was calculated. The HR ICP MS results were cross-checked by gamma ray spectroscopy analysis that was performed at the low background facility STELLA (Sub Terranean Low Levelmore » Assay) of the LNGS underground lab using HPGe detectors.« less

  20. 16 febbraio 2004. 121 Hermione occulta la stella TYC 1905-00864-1 in Gemini

    NASA Astrophysics Data System (ADS)

    Corbisiero, Massimo

    2005-04-01

    On 16 February 2004, the asteroid 121 Hermione occulted the star TYC 1905-00864-1 in Gemini: new astrometric observations and duplicity of the asteroid lead the UAI Occultation Section to launch a call for observations throughout Italy. Interesting results have been obtained along with new dimensions of the asteroid derived from positive observations.

  1. Designing a Dynamic Data Driven Application System for Estimating Real-Time Load of DOC in a River

    NASA Astrophysics Data System (ADS)

    Ouyang, Y.; None

    2011-12-01

    Understanding the dynamics of naturally occurring dissolved organic carbon (DOC) in a river is central to estimating surface water quality, aquatic carbon cycling, and climate change. Currently, determination of DOC in surface water is primarily accomplished by manually collecting samples for laboratory analysis, which requires at least 24 hours. In other words, no effort has been devoted to monitoring real-time variations of DOC in a river due to the lack of suitable and/or cost-effective wireless sensors. However, when considering human health, carbon footprints, and effects of urbanization, industry, and agriculture on water resource supply, timely DOC information may be critical. We have developed here a new paradigm, a dynamic data driven application system (DDDAS), for estimating the real-time load of DOC into a river. This DDDAS consisted of the following four components: (1) a Visual Basic (VB) program for downloading US Geological Survey real-time chlorophyll and discharge data; (2) a STELLA model for evaluating real-time DOC load based on the relationship between chlorophyll a, DOC, and river discharge; (3) a batch file for linking the VB program and STELLA model; and (4) a Microsoft Windows Scheduled Tasks wizard for executing the model and displaying output on a computer screen at selected times. Results show that the real-time load of DOC into the St. Johns River basin near Satsuma, Putnam County, Florida, USA varied over a range from -13,143 to 29,248 kg/h at the selected site in Florida, USA. The negative loads occurred because of the back flow in the estuarine reach of the river. The cumulative load of DOC in the river for the selected site at the end of the simulation (178 hours) was about 1.2 tons. Our results support the utility of the DDDAS developed in this study for estimating the real-time variations of DOC in river ecosystems.

  2. Antisolar differential rotation with surface lithium enrichment on the single K-giant V1192 Orionis

    NASA Astrophysics Data System (ADS)

    Kővári, Zs.; Strassmeier, K. G.; Carroll, T. A.; Oláh, K.; Kriskovics, L.; Kővári, E.; Kovács, O.; Vida, K.; Granzer, T.; Weber, M.

    2017-10-01

    Context. Stars with about 1-2 solar masses at the red giant branch (RGB) represent an intriguing period of stellar evolution, I.e. when the convective envelope interacts with the fast-rotating core. During these mixing episodes freshly synthesized lithium can come up to the stellar surface along with high angular momentum material. This high angular momentum may alter the surface rotation pattern. Aims: The single rapidly rotating K-giant V1192 Ori is revisited to determine its surface differential rotation, lithium abundance, and basic stellar properties such as a precise rotation period. The aim is to independently verify the antisolar differential rotation of the star and possibly find a connection to the surface lithium abundance. Methods: We applied time-series Doppler imaging to a new multi-epoch data set. Altogether we reconstructed 11 Doppler images from spectroscopic data collected with the STELLA robotic telescope between 2007-2016. We used our inversion code iMap to reconstruct all stellar surface maps. We extracted the differential rotation from these images by tracing systematic spot migration as a function of stellar latitude from consecutive image cross-correlations. Results: The position of V1192 Ori in the Hertzsprung-Russell diagram suggests that the star is in the helium core-burning phase just leaving the RGB bump. We measure A(Li)NLTE = 1.27, I.e. a value close to the anticipated transition value of 1.5 from Li-normal to Li-rich giants. Doppler images reveal extended dark areas arranged quasi-evenly along an equatorial belt. No cool polar spot is found during the investigated epoch. Spot displacements clearly suggest antisolar surface differential rotation with α = - 0.11 ± 0.02 shear coefficient. Conclusions: The surface Li enrichment and the peculiar surface rotation pattern may indicate a common origin. Based on data obtained with the STELLA robotic observatory in Tenerife, an AIP facility jointly operated by AIP and IAC.

  3. The stars and the birds in a school life

    NASA Astrophysics Data System (ADS)

    Jokin, Ivo

    2010-05-01

    The Stars in a School s Life Astroparty is held every year and its 6st edition was held in this year. Owing to it a lot of new Astronomy clubs are built up at regional level; the party itself rouses interest in Astronomy as a science and as a subject in school as well.When taking part in the party students get more skills both in theory itself and in making watching experiments of space. They learn how to analize and describe such experiments. These activities are not held at schools competitions in Astronomy. The party itself gives a lot of possibilities for carrying out a variety of methodical activities with Physics and Astronomy teachers. We think that this is the way of joining of the children to natural sciences and mastering of sound knowledge and skills. Another important idea of Astro Party is the integration of astronomy with biology, in particular ecology - use of the telescopes for observation of water-floating and water-loving birds. Aims: - Rising students, interest in Astronomy and watching space; - Providing a suitable environment for developing teachers and students creative and intellectual skills; - Exchange of teaching experience. Work , style and methods: innovation methods, team work, workshop, students that proved to be good in Astronomy teach their classmates beginners. The Birds in a School's Life http://www.stella-science.eu/pool_good_practices.php This eBook ‘Science Education in European Schools - Selected Practices from the STELLA Catalogue' provides a sample of selected practices, collected in the scope of the European Lifelong Learning Programme. Project STELLA (Science Teaching in a Lifelong Learning Approach) in order to support educational authorities, school heads and science teachers in fostering and adopting innovative practices in science education. INITIATIVE The aim of the initiative is that of raising young people's interest in learning about the nature of local birdlife including waterfowl as well as those of the

  4. A Study of the Efficacy of Project-Based Learning Integrated with Computer-Based Simulation--STELLA

    ERIC Educational Resources Information Center

    Eskrootchi, Rogheyeh; Oskrochi, G. Reza

    2010-01-01

    Incorporating computer-simulation modelling into project-based learning may be effective but requires careful planning and implementation. Teachers, especially, need pedagogical content knowledge which refers to knowledge about how students learn from materials infused with technology. This study suggests that students learn best by actively…

  5. A STELLA model to estimate soil CO2 emissions from a short-rotation woody crop

    Treesearch

    Ying Ouyang; Theodor D. Leininger; Jeff Hatten; Prem B. Parajuli

    2012-01-01

    The potential for climatic factors as well as soil–plant–climate interactions to change as a result of rising levels of atmospheric CO2 concentration is an issue of increasing international environmental concern. Agricultural and forest practices and managements may be important contributors to mitigating elevated atmospheric CO2...

  6. Rotation and magnetic activity of the Hertzsprung-gap giant 31 Comae

    NASA Astrophysics Data System (ADS)

    Strassmeier, K. G.; Granzer, T.; Kopf, M.; Weber, M.; Küker, M.; Reegen, P.; Rice, J. B.; Matthews, J. M.; Kuschnig, R.; Rowe, J. F.; Guenther, D. B.; Moffat, A. F. J.; Rucinski, S. M.; Sasselov, D.; Weiss, W. W.

    2010-09-01

    Context. The single rapidly-rotating G0 giant 31 Comae has been a puzzle because of the absence of photometric variability despite its strong chromospheric and coronal emissions. As a Hertzsprung-gap giant, it is expected to be at the stage of rearranging its moment of inertia, hence likely also its dynamo action, which could possibly be linked with its missing photospheric activity. Aims: Our aim is to detect photospheric activity, obtain the rotation period, and use it for a first Doppler image of the star's surface. Its morphology could be related to the evolutionary status. Methods: We carried out high-precision, white-light photometry with the MOST satellite, ground-based Strömgren photometry with automated telescopes, and high-resolution optical echelle spectroscopy with the new STELLA robotic facility. Results: The MOST data reveal, for the first time, light variations with a full amplitude of 5 mmag and an average photometric period of 6.80 ± 0.06 days. Radial-velocity variations with a full amplitude of 270 m s-1 and a period of 6.76 ± 0.02 days were detected from our STELLA spectra, which we also interpret as due to stellar rotation. The two-year constancy of the average radial velocity of +0.10 ± 0.33 km s-1 confirms the star's single status, as well as the membership in the cluster Melotte 111. A spectrum synthesis gives Teff = 5660 ± 42 K, log g = 3.51 ± 0.09, and [Fe/H] = -0.15 ± 0.03, which together with the revised Hipparcos distance, suggests a mass of 2.6 ± 0.1 M_⊙ and an age of ≈540 Myr. The surface lithium abundance is measured to be nearly primordial. A detection of a strong He i absorption line indicates nonradiative heating processes in the atmosphere. Our Doppler images show a large, asymmetric polar spot, cooler than Teff by ≈1600 K, and several small low-to-mid latitude features that are warmer by ≈300-400 K and are possibly of chromospheric origin. We computed the convective turnover time for 31 Com as a function of depth

  7. INTRODUCTION TO SUSTAINABLE MANAGEMENT APPROACHES AND REVITALIZATION TOOLS-ELECTRONIC (SMARTE): IMPROVING REVITALIZATION DECISIONS IN STELLA, MISSOURI

    EPA Science Inventory

    SMARTe (Sustainable Management Approaches and Revitalization Tools-electronic) is a web-based decision support tool being developed by the Office of Research and Development (ORD) in partnership with the Office of Brownfields Cleanup and ...

  8. A STELLA model to estimate water and nitrogen dynamics in a short-rotation woody crop plantation

    Treesearch

    Ying Ouyang; Jiaen Zhang; Theodor D. Leininger; Brent R. Frey

    2015-01-01

    Although short-rotation woody crop biomass production technology has demonstrated a promising potential to supply feedstocks for bioenergy production, the water and nutrient processes in the woody crop planation ecosystem are poorly understood. In this study, a computer model was developed to estimate the dynamics of water and nitrogen (N) species (e.g., NH4...

  9. Publisher Correction: Embryonic defects induced by maternal obesity in mice derive from Stella insufficiency in oocytes.

    PubMed

    Han, Longsen; Ren, Chao; Li, Ling; Li, Xiaoyan; Ge, Juan; Wang, Haichao; Miao, Yi-Liang; Guo, Xuejiang; Moley, Kelle H; Shu, Wenjie; Wang, Qiang

    2018-05-01

    In the version of this article originally published, the positions of Wenjie Shu and Qiang Wang in the author list were reversed and incorrect images were displayed in the HTML for Supplementary Figs. 1-12. The errors have been corrected in the HTML and PDF versions of the article.

  10. Teaching sustainability science from a systems analysis perspective: MSc course at Utrecht University

    NASA Astrophysics Data System (ADS)

    Santos, Maria J.; de Boer, Hugo; Dekker, Stefan

    2017-04-01

    Sustainability science has emerged as a key discipline that embraces both disciplinary depth and interdisciplinary breadth. The challenge is to design University courses that convey both properties without sacrificing either of them. Here we present the design of such course at Utrecht University (the Netherlands) for the MSC program 'Sustainable Development' and discuss the perceived learning and student evaluations. Our course (Sustainability Modelling and Indicators (SMI)) follows an introductory course on Sustainability Perspectives. SMI philosophy is that system thinking and system analysis is central to sustainability science. To convey this philosophy, we focus on four themes: the Anthropocene, Food security, Energy security and Agency and decision making. We developed four hands-on assignments with increasing complexity and make use of different software (Stella, Excel, IMAGE and Netlogo). The assignments aimed at: (1) teaching students the system components by using a pre-existing model in Stella, (2) challenge students to build their own coupled system in Excel, (3) assess outputs from the fully-coupled and dynamic model integrated assessment model IMAGE, and (4) understand emergent properties using an agent-based model in Netlogo. Based on detailed student evaluations (n = 95) we found that the mathematics presented a manageable challenge to a part of the students. The student pool identified a priori having higher experience with Excel in comparison with other software. Netlogo was the highest ranked software in the student evaluations and this was linked to its user-interface with moving agents. The Excel assignment received the highest and lowest scores, and students found it challenging, time consuming but also indicated that they learned the most from this assignment. Students graded what we considered 'easy' assignments with the highest grades. These results suggest that a systems analytical approach to sustainability science can be operationalized

  11. Surface exponents of trails in two dimensions at tricriticality: Computer simulation study

    NASA Astrophysics Data System (ADS)

    Meirovitch, H.; Chang, I. S.; Shapir, Y.

    1989-09-01

    Using the scanning simulation method, we study self-attracting trails (with energy ɛ per intersection) terminally attached to an im- penetrable linear boundary on a square lattice at their tricrital collapse transition. Our results for the exponents of the partition functions are γ1=0.634+/-0.025 (one end attached to the surface) and γ11=-0.44+/-0.02 (both ends attached). These values (with 95% significance limits) are within the error bars of the numerical estimates of Seno and Stella [Europhys. Lett. 7, 605 (1989)] for self-avoiding walks (SAW's) at the FTHETA-point on the same lattice. Our results, however, differ significantly from the exact values derived by Duplantier and Saleur for SAW's on a dilute hexagonal lattice at the FTHETA' point. The collapse temperature Tt and the tricritical growth parameter μ are very close to their analytic bounds -ɛ/kBTt=ln3 and μ=3.

  12. Fossil shell emission in dying radio loud AGNs

    NASA Astrophysics Data System (ADS)

    Kino, M.; Ito, H.; Kawakatu, N.; Orienti, M.; Nagai, H.; Wajima, K.; Itoh, R.

    2016-02-01

    We investigate shell emission associated with dying radio loud AGNs. First, based on our recent work by Ito et al. (2015), we describe the dynamical and spectral evolution of shells after stopping the jet energy injection. We find that the shell emission overwhelms that of the radio lobes soon after stopping the jet energy injection because fresh electrons are continuously supplied into the shell via the forward shock, while the radio lobes rapidly fade out without jet energy injection. We find that such fossil shells can be a new class of target sources for SKA telescope. Next, we apply the model to the nearby radio source 3C84. Then, we find that the fossil shell emission in 3C84 is less luminous in the radio band while it is bright in the TeV γ-ray band and can be detectable by CTA. Data from STELLA

  13. The magnetic field and the evolution of element spots on the surface of the HgMn eclipsing binary ARAur

    NASA Astrophysics Data System (ADS)

    Hubrig, S.; Savanov, I.; Ilyin, I.; González, J. F.; Korhonen, H.; Lehmann, H.; Schöller, M.; Granzer, T.; Weber, M.; Strassmeier, K. G.; Hartmann, M.; Tkachenko, A.

    2010-10-01

    The system ARAur is a young late B-type double-lined eclipsing binary with a primary star of HgMn peculiarity. We applied the Doppler imaging method to reconstruct the distribution of Fe and Y over the surface of the primary using spectroscopic time series obtained in 2005 and from 2008 October to 2009 February. The results show a remarkable evolution of the element distribution and overabundances. Measurements of the magnetic field with the moment technique using several elements reveal the presence of a longitudinal magnetic field of the order of a few hundred gauss in both stellar components and a quadratic field of the order of 8kG on the surface of the primary star. Based on observations obtained at the 2.56-m Nordic Optical Telescope on La Palma, the Karl-Schwarzschild-Observatorium in Tautenburg and the STELLA robotic telescope on Tenerife. E-mail: shubrig@aip.de

  14. Pulsational Pair-instability Model for Superluminous Supernova PTF12dam: Interaction and Radioactive Decay

    NASA Astrophysics Data System (ADS)

    Tolstov, Alexey; Nomoto, Ken'ichi; Blinnikov, Sergei; Sorokina, Elena; Quimby, Robert; Baklanov, Petr

    2017-02-01

    Being a superluminous supernova, PTF12dam can be explained by a 56Ni-powered model, a magnetar-powered model, or an interaction model. We propose that PTF12dam is a pulsational pair-instability supernova, where the outer envelope of a progenitor is ejected during the pulsations. Thus, it is powered by a double energy source: radioactive decay of 56Ni and a radiative shock in a dense circumstellar medium. To describe multicolor light curves and spectra, we use radiation-hydrodynamics calculations of the STELLA code. We found that light curves are well described in the model with 40 M⊙ ejecta and 20-40 M⊙ circumstellar medium. The ejected 56Ni mass is about 6 M⊙, which results from explosive nucleosynthesis with large explosion energy (2-3) × 1052 erg. In comparison with alternative scenarios of pair-instability supernova and magnetar-powered supernova, in the interaction model, all the observed main photometric characteristics are well reproduced: multicolor light curves, color temperatures, and photospheric velocities.

  15. Spot evolution on the red giant star XX Triangulum. A starspot-decay analysis based on time-series Doppler imaging

    NASA Astrophysics Data System (ADS)

    Künstler, A.; Carroll, T. A.; Strassmeier, K. G.

    2015-06-01

    Context. Solar spots appear to decay linearly proportional to their size. The decay rate of solar spots is directly related to magnetic diffusivity, which itself is a key quantity for the length of a magnetic-activity cycle. Is a linear spot decay also seen on other stars, and is this in agreement with the large range of solar and stellar activity cycle lengths? Aims: We investigate the evolution of starspots on the rapidly-rotating (Prot≈24 d) K0 giant XX Tri, using consecutive time-series Doppler images. Our aim is to obtain a well-sampled movie of the stellar surface over many years, and thereby detect and quantify a starspot decay law for further comparison with the Sun. Methods: We obtained continuous high-resolution and phase-resolved spectroscopy with the 1.2-m robotic STELLA telescope on Tenerife over six years, and these observations are ongoing. For each observing season, we obtained between 5 to 7 independent Doppler images, one per stellar rotation, making up a total of 36 maps. All images were reconstructed with our line-profile inversion code iMap. A wavelet analysis was implemented for denoising the line profiles. To quantify starspot area decay and growth, we match the observed images with simplified spot models based on a Monte Carlo approach. Results: It is shown that the surface of XX Tri is covered with large high-latitude and even polar spots and with occasional small equatorial spots. Just over the course of six years, we see a systematically changing spot distribution with various timescales and morphology, such as spot fragmentation and spot merging as well as spot decay and formation. An average linear decay of D = -0.022 ± 0.002 SH/day is inferred. We found evidence of an active longitude in phase toward the (unseen) companion star. Furthermore, we detect a weak solar-like differential rotation with a surface shear of α = 0.016 ± 0.003. From the decay rate, we determine a turbulent diffusivity of ηT = (6.3 ± 0.5) × 1014 cm2/s and

  16. The Hippo Signaling Pathway Regulates Ovarian Function via the Proliferation of Ovarian Germline Stem Cells.

    PubMed

    Ye, Haifeng; Li, Xiaoyan; Zheng, Tuochen; Hu, Chuan; Pan, Zezheng; Huang, Jian; Li, Jia; Li, Wei; Zheng, Yuehui

    2017-01-01

    To improve the separation, identification and cultivation of ovarian germline stem cells (OGSCs), to clarify the relationship between the Hippo signaling pathway effector YAP1 and the proliferation and differentiation of OGSCs in vitro and to identify the major contribution of Hippo signaling to ovarian function. Two-step enzymatic separation processes and magnetic separation were used to isolate and identify OGSCs by determining the expression of Mvh, Oct4, Nanog, Fragilis and Stella markers. Then, YAP1, as the main effector molecule in the Hippo signaling pathway, was chosen as the target gene of the study. Lentivirus containing overexpressed YAP1 or a YAP1-targeted shRNA was transduced into OGSCs. The effects of modulating the Hippo signaling pathway on the proliferation, differentiation, reproduction and endocrine function of ovaries were observed by microinjecting the lentiviral vectors with overexpressed YAP1 or YAP1 shRNA into infertile mouse models or natural mice of reproductive age. (1) The specific expression of Mvh, Oct4, Nanog, Fragilis and Stella markers was observed in isolated stem cells. Thus, the isolated cells were preliminarily identified as OGSCs. (2) The co-expression of LATS2, MST1, YAP1 and MVH was observed in isolated OGSCs. Mvh and Oct4 expression levels were significantly increased in OGSCs overexpressing YAP1 compared to GFP controls. Consistently, Mvh and Oct4 levels were significantly decreased in cells expressing YAP1-targeted shRNA. (3) After 14-75 days of YAP1 overexpression in infertile mouse models, we detected follicle regeneration in ovaries, the activation of primordial follicles and increased birth rate, accompanied by increasing levels of E2 and FSH. (4) However, we detected decreasing follicles in ovaries, lower birth rate, and decreasing E2 and FSH in serum from healthy mice of reproductive age following YAP1 shRNA expression. Methods for the isolation, identification and culture of OGSCs were successfully established

  17. APPLICATION OF SUSTAINABILITY CRITERIA TO STELLA, MISSOURI-ENVIRONMENTAL PLANNING-PRELIMINARY SITE INFORMATION AND ELEMENTS OF THE MASTER PLAN

    EPA Science Inventory

    Natural systems provide essential goods and services that make human life possible. Because development of the built environment will cumulatively consume natural capital, it is essential that the conditions that maintain natural systems must become the constraints and performanc...

  18. APPLICATION OF SUSTAINABILITY CRITERIA TO STELLA, MISSOURI-INTEGRATED PLANNING-PRELIMINARY SITE INFORMATION AND ELEMENTS OF THE MASTER PLAN

    EPA Science Inventory

    Sustainability in the context of a place is a set of responses to social, economic, and environmental criteria. Individually, these sets of criteria were addressed in prior presentations. This presentation illustrates the application of these three sets of criteria combined with ...

  19. Reclaiming the Word "Standards": Professional Standards for Teachers of English Language and Literacy in Australia (the STELLA Project).

    ERIC Educational Resources Information Center

    Doecke, Brenton; Gill, Margaret; McClenaghan, Douglas

    In 1998, the Australian Research Council provided funding for a three year research project to develop professional standards and assessments for the English teaching profession. The project team is a consortium of researchers from three major universities together with the two national English teaching associations and representatives from state…

  20. Testing sex and gender in sports; reinventing, reimagining and reconstructing histories.

    PubMed

    Heggie, Vanessa

    2010-12-01

    Most international sports organisations work on the premise that human beings come in one of two genders: male or female. Consequently, all athletes, including intersex and transgender individuals, must be assigned to compete in one or other category. Since the 1930s (not, as is popularly suggested, the 1960s) these organisations have relied on scientific and medical professionals to provide an 'objective' judgement of an athlete's eligibility to compete in women's national and international sporting events. The changing nature of these judgements reflects a great deal about our cultural, social and national prejudices, while the matter of testing itself has become a site of conflict for feminists and human rights activists. Because of the sensitive nature of this subject, histories of sex testing are difficult to write and research; this has lead to the repetition of inaccurate information and false assertions about gender fraud, particularly in relation to the 'classic' cases of Stella Walsh and Heinrich/Hermann/Dora Ratjen. As historians, we need to be extremely careful to differentiate between mythologies and histories. Copyright © 2010 Elsevier Ltd. All rights reserved.

  1. Testing sex and gender in sports; reinventing, reimagining and reconstructing histories

    PubMed Central

    Heggie, Vanessa

    2010-01-01

    Most international sports organisations work on the premise that human beings come in one of two genders: male or female. Consequently, all athletes, including intersex and transgender individuals, must be assigned to compete in one or other category. Since the 1930s (not, as is popularly suggested, the 1960s) these organisations have relied on scientific and medical professionals to provide an ‘objective’ judgement of an athlete's eligibility to compete in women's national and international sporting events. The changing nature of these judgements reflects a great deal about our cultural, social and national prejudices, while the matter of testing itself has become a site of conflict for feminists and human rights activists. Because of the sensitive nature of this subject, histories of sex testing are difficult to write and research; this has lead to the repetition of inaccurate information and false assertions about gender fraud, particularly in relation to the ‘classic’ cases of Stella Walsh and Heinrich/Hermann/Dora Ratjen. As historians, we need to be extremely careful to differentiate between mythologies and histories. PMID:20980057

  2. Tracking strategies for laser ranging to multiple satellite targets

    NASA Technical Reports Server (NTRS)

    Robbins, J. W.; Smith, D. E.; Kolenkiewicz, R.

    1994-01-01

    By the middle of the decade, several new Laser Geodynamic Satellites will be launched to join the current constellation comprised of the laser geodynamic satellite (LAGEOS) (US), Starlette (France), Ajisai (Japan), and Etalon I and II (USSR). The satellites to be launched, LAGEOS II and III (US & Italy), and Stella (France), will be injected into orbits that differ from the existing constellation so that geodetic and gravimetric quantities are sampled to enhance their resolution and accuracy. An examination of various possible tracking strategies adopted by the network of laser tracking stations has revealed that the recovery of precise geodetic parameters can be obtained over shorter intervals than is currently obtainable with the present constellation of satellites. This is particularly important in the planning of mobile laser tracking operations, given a network of permanently operating tracking sites. Through simulations, it is shown that laser tracking of certain satellite passes, pre-selected to provide optimal sky-coverage, provides the means to acquire a sufficient amount of data to allow the recovery of 1 cm station positions.

  3. Pulsational Pair-instability Model for Superluminous Supernova PTF12dam:Interaction and Radioactive Decay

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

    Tolstov, Alexey; Nomoto, Ken’ichi; Blinnikov, Sergei

    2017-02-01

    Being a superluminous supernova, PTF12dam can be explained by a {sup 56}Ni-powered model, a magnetar-powered model, or an interaction model. We propose that PTF12dam is a pulsational pair-instability supernova, where the outer envelope of a progenitor is ejected during the pulsations. Thus, it is powered by a double energy source: radioactive decay of {sup 56}Ni and a radiative shock in a dense circumstellar medium. To describe multicolor light curves and spectra, we use radiation-hydrodynamics calculations of the STELLA code. We found that light curves are well described in the model with 40 M {sub ⊙} ejecta and 20–40 M {submore » ⊙} circumstellar medium. The ejected {sup 56}Ni mass is about 6 M {sub ⊙}, which results from explosive nucleosynthesis with large explosion energy (2–3)×10{sup 52} erg. In comparison with alternative scenarios of pair-instability supernova and magnetar-powered supernova, in the interaction model, all the observed main photometric characteristics are well reproduced: multicolor light curves, color temperatures, and photospheric velocities.« less

  4. Steroids and triterpenes from the fruit bodies of Ganoderma lucidum and their anti-complement activity.

    PubMed

    Seo, Hyo Won; Hung, Tran Manh; Na, MinKyun; Jung, Hyun Ju; Kim, Jin Cheol; Choi, Jae Sue; Kim, Jung Hee; Lee, Hyeong-Kyu; Lee, IkSoo; Bae, KiHwan; Hattori, Masao; Min, Byung Sun

    2009-11-01

    To determine the anti-complement activity of natural triterpenes, chromatographic separation of the EtOAc-soluble fraction from the fruiting body of Ganoderma lucidum led to the isolation of three steroids and five triterpenoids. They were identified as ergosterol peroxide (1), ergosterol (2), genoderic acid Sz (3), stella sterol (4), ganoderic aic C1 (5), ganoderic acid A (6), methyl ganoderate A (7), and lucidenic acid A (8) based on spectroscopic evidence and physicochemical properties. These compounds were examined for their anti-complement activity against the classical pathway of the complement system. Compounds 2 and 3 showed potent anti-complement activity with IC50 values of 52.0 and 44.6 microM, respectively. Compound 1 exhibited significant inhibitory activity with an IC50 value of 126.8 microM, whereas compounds 4-8 were inactive. Our findings suggested that in addition to the ketone group at C-3, the delta7(8), delta9(11)-lanostadiene type triterpene also plays an important role in inhibiting the hemolytic activity of human serum against erythrocytes.

  5. [Safety and tolerability of psychotropic medications in childhood: preliminary data of a pharmacovigilance study].

    PubMed

    Magazù, A; Masi, G; Germanò, E; Gagliostro, M S; Siracusano, R; Arcoraci, V; Spina, E; Gagliano, A

    2014-06-01

    The aim of this study was to evaluate adverse drug reactions (ADRs) of psychotropic medications in childhood. One hundred and two children and adolescents (M 82.4%, F 17.6%) followed-up at the Division of Child Neurology and Psychiatry at the University of Messina, and at the Scientific Institute Child Neurology and Psychiatry, IRCCS Stella Maris, Calambrone, Pisa, were recruited between January 2009 and December 2011. All participants met DSM-IV diagnostic criteria for psychiatric disorders. The data were collected using a recording sheet for ADRs. An electronic database was also used. The recording sheet was designed to note all relevant information about drug treatment and ADRs according to AIFA (Agenzia Italiana del Farmaco) suggestions. The most prescribed drugs were: risperidone (19.6%), aripiprazole (18.4%) and valproic acid (14.8%). The ADRs more frequently recorded had been: weight gain (12.6%), sleepiness (8.4%), and irritability (6.7%). None of recorded ADRs were classified as "serious". This study can provide a basic model to collect information on safety and tolerability of psychotropic drugs in childhood.

  6. Second Star to the Right and Straight On!

    NASA Astrophysics Data System (ADS)

    Benacchio, L.

    2016-01-01

    The aim of the project “Second Star to the Right and Straight On!” is to recover the relationship between man and the sky, present all over our medieval city, but virtually invisible to inhabitants and tourists nowadays. The city we are speaking of is Padua, Italy, an ancient and noble one, with its seven-century-old university, the Scrovegni Chapel, where Giotto painted a comet—probably Halley's—for the first time, and many other monuments and frescoes in which the sky plays an important role. The city also features dozens of smaller pieces of artwork, such as paintings and coats of arms, on the external walls of historical buildings in the town center that also convey the same message. The product of this research will be a guide to Padua's sky for a completely new “astronomical” city tour available to the five million tourists visiting Padua every year as well as to Italian classrooms. The resources will be available as a book (in Italian), Seconda Stella a Destra, a website1, and an interactive mobile app.

  7. Remarkable Shifts in Offspring Provisioning during Gestation in a Live-Bearing Cnidarian

    PubMed Central

    Mercier, Annie; Sun, Zhao; Parrish, Christopher C.; Hamel, Jean-François

    2016-01-01

    Animals display diverse means of producing and provisioning offspring, from eggs to embryos and juveniles. While external development predominates, many forms of embryonic incubation have evolved, including placentation in mammals and a number of understudied variants in basal metazoans that could help understand evolutionary diversification. Here we studied the brooding sea anemone Aulactinia stella, using behavioural, morphological and biochemical indicators of offspring phenotype to characterize gestation and elucidate parental and sibling relationships. The pronounced variance in juvenile weight within broods was not strongly related to any of the typical external predictors (adult weight, clutch size, sampling date, environmental conditions). Lipid concentration was significantly higher in the tissues of the small juveniles than in those of large juveniles or adult, and fatty acid profiles tended to set small juveniles apart. Finally, intra-brood feeding on external resources was documented in larger juveniles. These results are consistent with ontogenetic shifts in nutrition, from vitellogenic provisioning to post-zygotic nourishment to a prenatal form of nursing upon acquisition of feeding organs, highlighting matrotrophic and conflict-driven mechanisms acting on offspring phenotype during gestation. PMID:27104375

  8. System Dynamics to Climate-Driven Water Budget Analysis in the Eastern Snake Plains Aquifer

    NASA Astrophysics Data System (ADS)

    Ryu, J.; Contor, B.; Wylie, A.; Johnson, G.; Allen, R. G.

    2010-12-01

    Climate variability, weather extremes and climate change continue to threaten the sustainability of water resources in the western United States. Given current climate change projections, increasing temperature is likely to modify the timing, form, and intensity of precipitation events, which consequently affect regional and local hydrologic cycles. As a result, drought, water shortage, and subsequent water conflicts may become an increasing threat in monotone hydrologic systems in arid lands, such as the Eastern Snake Plain Aquifer (ESPA). The ESPA, in particular, is a critical asset in the state of Idaho. It is known as the economic lifeblood for more than half of Idaho’s population so that water resources availability and aquifer management due to climate change is of great interest, especially over the next few decades. In this study, we apply system dynamics as a methodology with which to address dynamically complex problems in ESPA’s water resources management. Aquifer recharge and discharge dynamics are coded in STELLA modeling system as input and output, respectively to identify long-term behavior of aquifer responses to climate-driven hydrological changes.

  9. Diagnostic utility of hepatocyte nuclear factor 1-beta immunoreactivity in endometrial carcinomas: lack of specificity for endometrial clear cell carcinoma.

    PubMed

    Fadare, Oluwole; Liang, Sharon X

    2012-12-01

    Hepatocyte nuclear factor 1-beta (HNF1β) has recently emerged as a relatively sensitive and specific marker for ovarian clear cell carcinoma. The purpose of this study is to assess the diagnostic utility of this marker for endometrial clear cell carcinoma. Immunohistochemical analysis was performed on 75 endometrial tissues using a goat polyclonal antibody raised against a peptide mapping at the C-terminus of human HNF1β protein. The 75 cases included 15 clear cell carcinomas, 20 endometrioid carcinomas, 15 endometrial serous carcinomas/uterine papillary serous carcinomas, 20 cases of normal endometrium, 2 cases of clear cell metaplasia, and 3 cases of Arias Stella reaction. Staining interpretations were based on a semiquantitative scoring system, a 0 to 12+ continuous numerical scale that was derived by multiplying the extent of staining (0 to 4+ scale) by the intensity of staining (0 to 3+ scale) for each case. HNF1β expression was found to be present in a wide spectrum of tissues. Twenty-seven (54%) of the 50 carcinomas displayed at least focal nuclear HNF1β expression, including 11 (73%) of 15, 9 (60%) of 15, and 7 (35%) of 20 clear cell, serous, and endometrioid carcinomas, respectively. The average nuclear staining scores for clear cell carcinomas, endometrioid carcinomas, and serous carcinomas were 5.2, 1.4, and 4.1, respectively. Clear cell carcinomas and endometrioid carcinomas displayed statistically significant differences regarding their nuclear staining scores (P = 0.0027), but clear cell carcinomas and endometrial serous carcinomas did not (P = 0.45). The calculated sensitivity of any nuclear HNF1β expression in classifying a carcinoma as being of the clear cell histotype was 73%, whereas the specificity was 54%. Nineteen of 20 normal endometrium samples displayed at least focal nuclear expression of HNF1β, and this expression was often diffuse. The 5 cases of benign histologic mimics of clear cell carcinomas (Arias Stella reaction and clear

  10. Report to the Palau Ministry of Education on the Mathematics Project at Harris, Maris Stella, and Meyuns Elementary Schools, 1993.

    ERIC Educational Resources Information Center

    King, Irvin L.; Emesiochl, Masa-Aki

    Since 1985, the students in grades 2-8 in three selected elementary schools in Palau have been tested on basic math skills. This report describes the data collected in May 1993 and indicates the relative strengths and weaknesses of students at each grade level in each school. Major outcomes include: (1) the students at Harris School scored…

  11. Johannes Kepler and the Supernova of 1604

    NASA Astrophysics Data System (ADS)

    Boner, P. J.

    2006-08-01

    The brilliant luminary that first appeared in October 1604 was considered by many contemporaries to be a new star of unrivalled magnitude. Shining forth near the historic conjunction of Mars, Jupiter and Saturn, the new star held important implications for several areas of interest, notably astrology, astronomy, chronology and theology. Addressing all of these areas in his comprehensive book, De stella nova (1606), Johannes Kepler (1571-1630) studied the new star extensively under the aegis of Holy Roman Emperor Rudolf II (1552-1612) in Prague. The focus of the following presentation is Kepler's theory of the new star's origins in the celestial ether. Describing the heavens poetically as a fertile expanse of "liquid fields", Kepler suggested that the new star sprung from the celestial ether much like the numerous living beings in the sublunary realm which were spontaneously generated from the Earth. As evidence for his claim, Kepler pointed to the conspicuous mathematical patterns similarly observed in earthly and celestial entities. Kepler's efficient cause for this explanation, known as the animate faculty, accounted for both the generation and form of new phenomena in the celestial and terrestrial realms. The new star of 1604 proved to be no exception.

  12. Comparing modal noise and FRD of circular and non-circular cross-section fibres

    NASA Astrophysics Data System (ADS)

    Sablowski, D. P.; Plüschke, D.; Weber, M.; Strassmeier, K. G.; Järvinen, A.

    2016-03-01

    Modal noise is a common source of noise introduced to the measurements by optical fibres and is particularly important for fibre-fed spectroscopic instruments, especially for high-resolution measurements. This noise source can limit the signal-to-noise ratio and jeopardize photon-noise limited data. The subject of the present work is to compare measurements of modal noise and focal-ratio degradation (FRD) for several commonly used fibres. We study the influence of a simple mechanical scrambling method (excenter) on both FRD and modal noise. Measurements are performed with circular and octagonal fibres from Polymicro Technology (FBP-Series) with diameters of 100, 200, and 300 μm and for square and rectangular fibres from CeramOptec, among others. FRD measurements for the same sample of fibres are performed as a function of wavelength. Furthermore, we replaced the circular fibre of the STELLA-échelle-spectrograph (SES) in Tenerife with an octagonal and found a SNR increase by a factor of 1.6 at 678 nm. It is shown in the laboratory that an excenter with a large amplitude and low frequency will not influence the FRD but will reduce modal noise rather effectively by up to 180%.

  13. OGLE14-073 - a promising pair-instability supernova candidate

    NASA Astrophysics Data System (ADS)

    Kozyreva, Alexandra; Kromer, Markus; Noebauer, Ulrich M.; Hirschi, Raphael

    2018-05-01

    The recently discovered bright type II supernova OGLE14-073 evolved very slowly. The light curve rose to maximum for 90 days from discovery and then declined at a rate compatible with the radioactive decay of 56Co. In this study, we show that a pair-instability supernova is a plausible mechanism for this event. We calculate explosion models and light curves with the radiation hydrodynamics code STELLA starting from two MZAMS = 150 M⊙, Z=0.001 progenitors. We obtain satisfactory fits to OGLE14-073 broadband light curves by including additional 56Ni in the centre of the models and mixing hydrogen down into the inner layers of the ejecta to a radial mass coordinate of 10 M⊙. The extra 56Ni required points to a slightly more massive progenitor star. The mixing of hydrogen could be due to large scale mixing during the explosion. We also present synthetic spectra for our models simulated with the Monte Carlo radiative transfer code ARTIS. The synthetic spectra reproduce the main features of the observed spectra of OGLE14-073. We conclude that OGLE14-073 is one of the most promising candidates for a pair-instability explosion.

  14. Estimating the Earth's geometry, rotation and gravity field using a multi-satellite SLR solution

    NASA Astrophysics Data System (ADS)

    Stefka, V.; Blossfeld, M.; Mueller, H.; Gerstl, M.; Panafidina, N.

    2012-12-01

    Satellite Laser Ranging (SLR) is the unique technique to determine station coordinates, Earth Orientation Parameter (EOP) and Stokes coefficients of the Earth's gravity field in one common adjustment. These parameters form the so called "three pillars" (Plag & Pearlman, 2009) of the Global Geodetic Observing System (GGOS). In its function as official analysis center of the International Laser Ranging Service (ILRS), DGFI is developing and maintaining software to process SLR observations called "DGFI Orbit and Geodetic parameter estimation Software" (DOGS). The software is used to analyze SLR observations and to compute multi-satellite solutions. To take benefit of different orbit performances (e.g. inclination and altitude), a solution using ten different spherical satellites (ETALON1/2, LAGEOS1/2, STELLA, STARLETTE, AJISAI, LARETS, LARES, BLITS) covering the period of 12 years of observations is computed. The satellites are relatively weighted using a variance component estimation (VCE). The obtained weights are analyzed w.r.t. the potential of the satellite to monitor changes in the Earths geometry, rotation and gravity field. The estimated parameters (station coordinates and EOP) are validated w.r.t. official time series of the IERS. The Stokes coefficients are compared to recent gravity field solutions.

  15. Estimating the Earth's gravity field using a multi-satellite SLR solution

    NASA Astrophysics Data System (ADS)

    Bloßfeld, Mathis; Stefka, Vojtech; Müller, Horst; Gerstl, Michael

    2013-04-01

    Satellite Laser Ranging (SLR) is the unique technique to determine station coordinates, Earth Orientation Parameter (EOP) and Stokes coefficients of the Earth's gravity field in one common adjustment. These parameters form the so called "three pillars" (Plag & Pearlman, 2009) of the Global Geodetic Observing System (GGOS). In its function as official analysis center of the International Laser Ranging Service (ILRS), DGFI is developing and maintaining software to process SLR observations called "DGFI Orbit and Geodetic parameter estimation Software" (DOGS). The software is used to analyze SLR observations and to compute multi-satellite solutions. To take benefit of different orbit performances (e.g. inclination and altitude), a solution using ten different spherical satellites (ETALON1/2, LAGEOS1/2, STELLA, STARLETTE, AJISAI, LARETS, LARES, BLITS) covering 12 years of observations is computed. The satellites are relatively weighted using a variance component estimation (VCE). The obtained weights are analyzed w.r.t. the potential of the satellite to monitor changes in the Earths geometry, rotation and gravity field. The estimated parameters (station coordinates and EOP) are validated w.r.t. official time series of the IERS. The obtained Stokes coefficients are compared to recent gravity field solutions and discussed in detail.

  16. A dynamic simulation model of land-use, population, and rural livelihoods in the Central Rift Valley of Ethiopia.

    PubMed

    Garedew, Efrem; Sandewall, Mats; Soderberg, Ulf

    2012-01-01

    The dynamic interactions between society and land resources have to be taken into account when planning and managing natural resources. A computer model, using STELLA software, was developed through active participation of purposively selected farm households from different wealth groups, age groups and gender within a rural community and some members of Kebelle council. The aim of the modeling was to study the perceived changes in land-use, population and livelihoods over the next 30 years and to improve our understanding of the interactions among them. The modeling output is characterized by rapid population growth, declining farm size and household incomes, deteriorating woody vegetation cover and worsening land degradation if current conditions remain. However, through integrated intervention strategies (including forest increase, micro-finance, family planning, health and education) the woody vegetation cover is likely to increase in the landscape, population growth is likely to slow down and households' income is likely to improve. A validation assessment of the simulation model based on historical data on land-use and population from 1973 to 2006 showed that the model is relatively robust. We conclude that as a supporting tool, the simulation model can contribute to the decision making process.

  17. Investigation of gene expressions in differentiated cell derived bone marrow stem cells during bone morphogenetic protein-4 treatments with Fourier transform infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Zafari, Jaber; Jouni, Fatemeh Javani; Ahmadvand, Ali; Abdolmaleki, Parviz; Soodi, Malihe; Zendehdel, Rezvan

    2017-02-01

    A model was set up to predict the differentiation patterns based on the data extracted from FTIR spectroscopy. For this reason, bone marrow stem cells (BMSCs) were differentiated to primordial germ cells (PGCs). Changes in cellular macromolecules in the time of 0, 24, 48, 72, and 96 h of differentiation, as different steps of the differentiation procedure were investigated by using FTIR spectroscopy. Also, the expression of pluripotency (Oct-4, Nanog and c-Myc) and specific genes (Mvh, Stella and Fragilis) were investigated by real-time PCR. However, the expression of genes in five steps of differentiation was predicted by FTIR spectroscopy. FTIR spectra showed changes in the template of band intensities at different differentiation steps. There are increasing changes in the stepwise differentiation procedure for the ratio area of CH2, which is symmetric to CH2 asymmetric stretching. An ensemble of expert methods, including regression tree (RT), boosting algorithm (BA), and generalized regression neural network (GRNN), was the best method to predict the gene expression by FTIR spectroscopy. In conclusion, the model was able to distinguish the pattern of different steps from cell differentiation by using some useful features extracted from FTIR spectra.

  18. Testicular cell conditioned medium supports differentiation of embryonic stem cells into ovarian structures containing oocytes.

    PubMed

    Lacham-Kaplan, Orly; Chy, Hun; Trounson, Alan

    2006-02-01

    Previous reports and the current study have found that germ cell precursor cells appear in embryoid bodies (EBs) formed from mouse embryonic stem cells as identified by positive expression of specific germ cell markers such as Oct-3/4, Mvh, c-kit, Stella, and DAZL. We hypothesized that if exposed to appropriate growth factors, the germ cell precursor cells within the EBs would differentiate into gametes. The source for growth factors used in the present study is conditioned medium collected from testicular cell cultures prepared from the testes of newborn males. Testes at this stage of development contain most growth factors required for the transformation of germ stem cells into differentiated gametes. When EBs were cultured in the conditioned medium, they developed into ovarian structures, which contained putative oocytes. The oocytes were surrounded by one to two layers of flattened cells and did not have a visible zona pellucida. However, oocyte-specific markers such as Fig-alpha and ZP3 were found expressed by the ovarian structures. The production of oocytes using this method is repeatable and reliable and may be applicable to other mammalian species, including the human.

  19. Gravity Models from CHAMP and other Satellite Data

    NASA Technical Reports Server (NTRS)

    Lemoime, Frank G.; Cox, C. M.; Chinn, D. S.; Zelensky, N. P.; Thompson, B. F.; Rowlands, D. D.; Luthdke, S. B.; Nerem, R. S.

    2003-01-01

    CHAMP spacecraft is the first of a series of new spacecraft missions that are revolutionizing our ability to model the Earth's geopotential. We report on the analysis of over 100 days of CHAMP data in 2001 and 2002, merged with tracking data of other satellites such as Jason, Topex, GFO, Starlette, Stella, Spot-2, as well as satellite altimetry. We find that the CHAMP-only component of these solutions is a significant improvement over pre-CHAMP satellite only models with respect to the high degree information expressed by the geopotential model coefficients. For example, the variance of the differences with altimeter-derived anomalies through degree 70 is 2.80 mGal(sup 2) for the CHAMP-only solution based on 87 days of data vs. 10.19 mGal(sup 2) for EGM96S. Nonetheless, in order to model properly the various resonances to which different satellites are sensitive, we must include other satellite data. We evaluate the performance of these new CHAMP derived solutions with EGM96 and the EIGEN series of solutions. We review carefully the performance of these models for altimetric satellites.

  20. Mass balance assessment for mercury in Lake Champlain

    USGS Publications Warehouse

    Gao, N.; Armatas, N.G.; Shanley, J.B.; Kamman, N.C.; Miller, E.K.; Keeler, G.J.; Scherbatskoy, T.; Holsen, T.M.; Young, T.; McIlroy, L.; Drake, S.; Olsen, Bill; Cady, C.

    2006-01-01

    A mass balance model for mercury in Lake Champlain was developed in an effort to understand the sources, inventories, concentrations, and effects of mercury (Hg) contamination in the lake ecosystem. To construct the mass balance model, air, water, and sediment were sampled as a part of this project and other research/monitoring projects in the Lake Champlain Basin. This project produced a STELLA-based computer model and quantitative apportionments of the principal input and output pathways of Hg for each of 13 segments in the lake. The model Hg concentrations in the lake were consistent with measured concentrations. Specifically, the modeling identified surface water inflows as the largest direct contributor of Hg into the lake. Direct wet deposition to the lake was the second largest source of Hg followed by direct dry deposition. Volatilization and sedimentation losses were identified as the two major removal mechanisms. This study significantly improves previous estimates of the relative importance of Hg input pathways and of wet and dry deposition fluxes of Hg into Lake Champlain. It also provides new estimates of volatilization fluxes across different lake segments and sedimentation loss in the lake. ?? 2006 American Chemical Society.

  1. A Dynamic Simulation Model of Land-Use, Population, and Rural Livelihoods in the Central Rift Valley of Ethiopia

    NASA Astrophysics Data System (ADS)

    Garedew, Efrem; Sandewall, Mats; Soderberg, Ulf

    2012-01-01

    The dynamic interactions between society and land resources have to be taken into account when planning and managing natural resources. A computer model, using STELLA software, was developed through active participation of purposively selected farm households from different wealth groups, age groups and gender within a rural community and some members of Kebelle council. The aim of the modeling was to study the perceived changes in land-use, population and livelihoods over the next 30 years and to improve our understanding of the interactions among them. The modeling output is characterized by rapid population growth, declining farm size and household incomes, deteriorating woody vegetation cover and worsening land degradation if current conditions remain. However, through integrated intervention strategies (including forest increase, micro-finance, family planning, health and education) the woody vegetation cover is likely to increase in the landscape, population growth is likely to slow down and households' income is likely to improve. A validation assessment of the simulation model based on historical data on land-use and population from 1973 to 2006 showed that the model is relatively robust. We conclude that as a supporting tool, the simulation model can contribute to the decision making process.

  2. Multicolour modelling of SN 2013dx associated with GRB 130702A★

    NASA Astrophysics Data System (ADS)

    Volnova, A. A.; Pruzhinskaya, M. V.; Pozanenko, A. S.; Blinnikov, S. I.; Minaev, P. Yu.; Burkhonov, O. A.; Chernenko, A. M.; Ehgamberdiev, Sh. A.; Inasaridze, R.; Jelinek, M.; Khorunzhev, G. A.; Klunko, E. V.; Krugly, Yu. N.; Mazaeva, E. D.; Rumyantsev, V. V.; Volvach, A. E.

    2017-05-01

    We present optical observations of SN 2013dx, related to the Fermi burst GRB 130702A, which occurred at red shift z = 0.145. It is the second-best sampled gamma-ray burst (GRB)/supernova (SN) after SN 1998bw. The observational light curves contain more than 280 data points in the uBgrRiz filters until 88 d after the burst, and the data were collected from our observational collaboration (Maidanak Observatory, Abastumani Observatory, Crimean Astrophysical Observatory, Mondy Observatory, National Observatory of Turkey and Observatorio del Roque de los Muchachos) and from the literature. We model numerically the multicolour light curves using the one-dimensional radiation hydrodynamical code stella, previously widely implemented for modelling typical non-GRB SNe. The best-fitting model has the following parameters: pre-SN star mass M = 25 M⊙; mass of the compact remnant MCR = 6 M⊙; total energy of the outburst Eoburst = 3.5 × 1052 erg; pre-supernova star radius R = 100 R⊙; M_^{56Ni} = 0.2 M_{⊙}, which is totally mixed through the ejecta; MO = 16.6 M⊙; MSi = 1.2 M⊙ and MFe = 1.2 M⊙, and the radiative efficiency of the SN is 0.1 per cent.

  3. Wetland Water Cooling Partnership: The Use of Constructed Wetlands to Enhance Thermoelectric Power Plant Cooling and Mitigate the Demand of Surface Water Use

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

    Apfelbaum, Steven L.; Duvall, Kenneth W.; Nelson, Theresa M.

    Through the Phase I study segment of contract #DE-NT0006644 with the U.S. Department of Energy’s National Energy Technology Laboratory, Applied Ecological Services, Inc. and Sterling Energy Services, LLC (the AES/SES Team) explored the use of constructed wetlands to help address stresses on surface water and groundwater resources from thermoelectric power plant cooling and makeup water requirements. The project objectives were crafted to explore and develop implementable water conservation and cooling strategies using constructed wetlands (not existing, naturally occurring wetlands), with the goal of determining if this strategy has the potential to reduce surface water and groundwater withdrawals of thermoelectric powermore » plants throughout the country. Our team’s exploratory work has documented what appears to be a significant and practical potential for augmenting power plant cooling water resources for makeup supply at many, but not all, thermoelectric power plant sites. The intent is to help alleviate stress on existing surface water and groundwater resources through harvesting, storing, polishing and beneficially re-using critical water resources. Through literature review, development of conceptual created wetland plans, and STELLA-based modeling, the AES/SES team has developed heat and water balances for conventional thermoelectric power plants to evaluate wetland size requirements, water use, and comparative cooling technology costs. The ecological literature on organism tolerances to heated waters was used to understand the range of ecological outcomes achievable in created wetlands. This study suggests that wetlands and water harvesting can provide a practical and cost-effective strategy to augment cooling waters for thermoelectric power plants in many geographic settings of the United States, particularly east of the 100th meridian, and in coastal and riverine locations. The study concluded that constructed wetlands can have significant

  4. Telescope networking and user support via Remote Telescope Markup Language

    NASA Astrophysics Data System (ADS)

    Hessman, Frederic V.; Pennypacker, Carlton R.; Romero-Colmenero, Encarni; Tuparev, Georg

    2004-09-01

    Remote Telescope Markup Language (RTML) is an XML-based interface/document format designed to facilitate the exchange of astronomical observing requests and results between investigators and observatories as well as within networks of observatories. While originally created to support simple imaging telescope requests (Versions 1.0-2.1), RTML Version 3.0 now supports a wide range of applications, from request preparation, exposure calculation, spectroscopy, and observation reports to remote telescope scheduling, target-of-opportunity observations and telescope network administration. The elegance of RTML is that all of this is made possible using a public XML Schema which provides a general-purpose, easily parsed, and syntax-checked medium for the exchange of astronomical and user information while not restricting or otherwise constraining the use of the information at either end. Thus, RTML can be used to connect heterogeneous systems and their users without requiring major changes in existing local resources and procedures. Projects as very different as a number of advanced amateur observatories, the global Hands-On Universe project, the MONET network (robotic imaging), the STELLA consortium (robotic spectroscopy), and the 11-m Southern African Large Telescope are now using or intending to use RTML in various forms and for various purposes.

  5. Quantitative analysis of cellulose degradation and growth of cellulolytic bacteria in the rumen.

    PubMed

    Russell, James B; Muck, Richard E; Weimer, Paul J

    2009-02-01

    Ruminant animals digest cellulose via a symbiotic relationship with ruminal microorganisms. Because feedstuffs only remain in the rumen for a short time, the rate of cellulose digestion must be very rapid. This speed is facilitated by rumination, a process that returns food to the mouth to be rechewed. By decreasing particle size, the cellulose surface area can be increased by up to 10(6)-fold. The amount of cellulose digested is then a function of two competing rates, namely the digestion rate (K(d)) and the rate of passage of solids from the rumen (K(p)). Estimation of bacterial growth on cellulose is complicated by several factors: (1) energy must be expended for maintenance and growth of the cells, (2) only adherent cells are capable of degrading cellulose and (3) adherent cells can provide nonadherent cells with cellodextrins. Additionally, when ruminants are fed large amounts of cereal grain along with fiber, ruminal pH can decrease to a point where cellulolytic bacteria no longer grow. A dynamic model based on STELLA software is presented. This model evaluates all of the major aspects of ruminal cellulose degradation: (1) ingestion, digestion and passage of feed particles, (2) maintenance and growth of cellulolytic bacteria and (3) pH effects.

  6. Fast evolving pair-instability supernovae

    DOE PAGES

    Kozyreva, Alexandra; Gilmer, Matthew; Hirschi, Raphael; ...

    2016-10-06

    With an increasing number of superluminous supernovae (SLSNe) discovered the ques- tion of their origin remains open and causes heated debates in the supernova commu- nity. Currently, there are three proposed mechanisms for SLSNe: (1) pair-instability supernovae (PISN), (2) magnetar-driven supernovae, and (3) models in which the su- pernova ejecta interacts with a circumstellar material ejected before the explosion. Based on current observations of SLSNe, the PISN origin has been disfavoured for a number of reasons. Many PISN models provide overly broad light curves and too reddened spectra, because of massive ejecta and a high amount of nickel. In themore » cur- rent study we re-examine PISN properties using progenitor models computed with the GENEC code. We calculate supernova explosions with FLASH and light curve evolu- tion with the radiation hydrodynamics code STELLA. We find that high-mass models (200 M⊙ and 250 M⊙) at relatively high metallicity (Z=0.001) do not retain hydro- gen in the outer layers and produce relatively fast evolving PISNe Type I and might be suitable to explain some SLSNe. We also investigate uncertainties in light curve modelling due to codes, opacities, the nickel-bubble effect and progenitor structure and composition.« less

  7. Germline competency of parthenogenetic embryonic stem cells from immature oocytes of adult mouse ovary

    PubMed Central

    Liu, Zhong; Hu, Zhe; Pan, Xinghua; Li, Minshu; Togun, Taiwo A.; Tuck, David; Pelizzola, Mattia; Huang, Junjiu; Ye, Xiaoying; Yin, Yu; Liu, Mengyuan; Li, Chao; Chen, Zhisheng; Wang, Fang; Zhou, Lingjun; Chen, Lingyi; Keefe, David L.; Liu, Lin

    2011-01-01

    Parthenogenetic embryonic stem cells (pESCs) have been generated in several mammalian species from parthenogenetic embryos that would otherwise die around mid-gestation. However, previous reports suggest that pESCs derived from in vivo ovulated (IVO) mature oocytes show limited pluripotency, as evidenced by low chimera production, high tissue preference and especially deficiency in germline competence, a critical test for genetic integrity and pluripotency of ESCs. Here, we report efficient generation of germline-competent pESC lines (named as IVM pESCs) from parthenogenetic embryos developed from immature oocytes of adult mouse ovaries following in vitro maturation (IVM) and artificial activation. In contrast, pESCs derived from IVO oocytes show defective germline competence, consistent with previous reports. Further, IVM pESCs resemble more ESCs from fertilized embryos (fESCs) than do IVO pESCs on genome-wide DNA methylation and global protein profiles. In addition, IVM pESCs express higher levels of Blimp1, Lin28 and Stella, relative to fESCs, and in their embryoid bodies following differentiation. This may indicate differences in differentiation potentially to the germline. The mechanisms for acquisition of pluripotency and germline competency of IVM pESCs from immature oocytes remain to be determined. PMID:21239471

  8. Toward an understanding of the pathophysiology of clear cell carcinoma of the ovary (Review)

    PubMed Central

    UEKURI, CHIHARU; SHIGETOMI, HIROSHI; ONO, SUMIRE; SASAKI, YOSHIKAZU; MATSUURA, MIYUKI; KOBAYASHI, HIROSHI

    2013-01-01

    Endometriosis-associated ovarian cancers demonstrate substantial morphological and genetic diversity. The transcription factor, hepatocyte nuclear factor (HNF)-1β, may be one of several key genes involved in the identity of ovarian clear cell carcinoma (CCC). The present study reviews a considerably expanded set of HNF-1β-associated genes and proteins that determine the pathophysiology of CCC. The current literature was reviewed by searching MEDLINE/PubMed. Functional interpretations of gene expression profiling in CCC are provided. Several important CCC-related genes overlap with those known to be regulated by the upregulation of HNF-1β expression, along with a lack of estrogen receptor (ER) expression. Furthermore, the genetic expression pattern in CCC resembles that of the Arias-Stella reaction, decidualization and placentation. HNF-1β regulates a subset of progesterone target genes. HNF-1β may also act as a modulator of female reproduction, playing a role in endometrial regeneration, differentiation, decidualization, glycogen synthesis, detoxification, cell cycle regulation, implantation, uterine receptivity and a successful pregnancy. In conclusion, the present study focused on reviewing the aberrant expression of CCC-specific genes and provided an update on the pathological implications and molecular functions of well-characterized CCC-specific genes. PMID:24179489

  9. APPLICATION OF SUSTAINABILITY CRITERIA TO STELLA, MISSOURI-ECONOMIC PLANNING-PRELIMINARY SITE INFORMATION AND ELEMENTS OF THE MASTER PLAN-16NOV2006 (1130)

    EPA Science Inventory

    Economic systems constraints and performance requirements that are essential to providing goods and services, jobs, and a functioning economic system form a list of criteria for planning a sustainable economy. This presentation places these economic criteria in the context of Ste...

  10. [Breast-feeding training programme as intervention approach at the hospital level: results of evaluation of the first phase of the STELLA study].

    PubMed

    Meyer, N; Spegel, H; Hendrowarsito, L; Schwegler, U; Fromme, H; Bolte, G

    2012-01-01

    The health-promoting short- and long-term effects of breast-feeding are supported by a vast scientific literature. The Bavarian prospective cohort study 2005/2006 showed regional variations of breast-feeding rates. Furthermore, improvement in counselling mothers, particularly with regard to prevention and handling of breast-feeding problems, has a great potential for health promotion. The objective of this study is to promote breast-feeding in maternity clinics by improving the surrounding conditions. A clinic-based and community-related intervention trial was carried out in Lower Bavaria as a model region with below average breast-feeding rates. (1) INTERVENTION: an advanced training of maternity ward professionals of 10 hospitals and after-care midwives was performed from May until December 2008. The training programme was based on the WHO/UNICEF criteria of the "Ten Steps to Successful Breastfeeding" to deepen the breast-feeding knowledge and to improve the breast-feeding management. (2) EVALUATION: A singular assessment of the advanced training programme was undertaken concerning an increase of knowledge and the practicability in clinical everyday life by participants; improvements of the maternity wards were assessed via structural interviews with maternity ward staff before and after intervention. Approximately 85% (n=378) of the staff of the 10 maternity clinics attended the training course. The survey after the training programme (response rate 83%) indicated that more than 80% of the participants stated to have learned something new and to be able to use the knowledge acquired for their own practice. Results of the clinic interviews showed a transfer of training contents into clinical work routines. Improvements at interview date were shown best for bonding (all 10 maternity clinics), for additional feeding (8 maternity clinics) as well as for 24-h rooming-in and mother counselling (7 maternal clinics each). Training of maternity ward professionals accounts for baby-friendly conditions in maternity clinics. Most willingness for improvements was shown by maternity ward staff particularly for bonding between mother and child as well as for additional feeding. Considerable differences between the hospitals were observed for the promotion of infant formulas before and after the intervention. © Georg Thieme Verlag KG Stuttgart · New York.

  11. Safety of ipragliflozin in elderly Japanese patients with type 2 diabetes mellitus (STELLA-ELDER): Interim results of a post-marketing surveillance study.

    PubMed

    Terauchi, Yasuo; Yokote, Koutaro; Nakamura, Ichiro; Sugamori, Haruko

    2016-01-01

    To determine the incidence of adverse drug reactions (ADRs) associated with ipragliflozin in elderly Japanese patients with type 2 diabetes mellitus. We report interim results of a postmarketing surveillance survey. Japanese physicians recorded ADRs in elderly patients (≥ 65 years old) who were first prescribed with ipragliflozin within 3 months of its launch (April 2014). Incidence of ADRs within 1 year of starting treatment with ipragliflozin. 898 ADRs occurred in 721/7,170 patients (10.06%). Skin complication-, volume depletion-, genital infection-, polyuria/pollakiuria-, urinary tract infection-, and hypoglycemia-related ADRs occurred in 2.23%, 1.90%, 1.45%, 1.32%, 0.77%, and 0.32%, respectively. ADRs were classified as serious in 44 (0.61%) patients. Half of the ADRs occurred within 30 days of starting treatment. There were no cases of Stevens-Johnson syndrome or toxic epidermal necrolysis. Most (92.1%) of the ADRs resolved or improved. Glycated hemoglobin, fasting blood glucose, body weight, and systolic blood pressure decreased by 0.6% (baseline 7.8%), 22.7 mg/dL (baseline 163.0 mg/dL), 2.3 kg (baseline 67.4 kg), and 3.1 mmHg (baseline 133.2 mmHg), respectively, from baseline to treatment discontinuation/last visit. Ipragliflozin is well tolerated and reduced surrogate endpoints in elderly Japanese patients with type 2 diabetes mellitus. Clinicaltrials.gov identifier: NCT02297620.

  12. Binary-induced magnetic activity?. Time-series echelle spectroscopy and photometry of HD 123351 = CZ CVn

    NASA Astrophysics Data System (ADS)

    Strassmeier, K. G.; Carroll, T. A.; Weber, M.; Granzer, T.; Bartus, J.; Oláh, K.; Rice, J. B.

    2011-11-01

    Context. Multi-wavelength time-series observations with high cadence and long duration are needed to resolve and understand the many variations of magnetically active late-type stars, which is an approach often used to observe the Sun. Aims: We present a first and detailed study of the bright and active K0IV-III star HD 123351. Methods: We acquired a total of 955 high-resolution STELLA echelle spectra during the years 2006-2010 and a total of 2260 photometric VIC data points during 1998-2010. These data are complemented by some spectra from CFHT and KPNO. Results: The star is found to be a single-lined spectroscopic binary with a period of 147.8919 ± 0.0003 days and a large eccentricity of e = 0.8086 ± 0.0001. The rms of the orbital solution is just 47 m s-1, making it the most precise orbit ever obtained for an active binary system. The rotation period is constrained from long-term photometry to be 58.32 ± 0.01 days. It shows that HD 123351 is a very asynchronous rotator, rotating five times slower than the expected pseudo-synchronous value. Two spotted regions persisted throughout the 12 years of our observations. We interpret them as active longitudes on a differentially rotating surface with a ΔP/P of 0.076. Four years of Hα, Ca ii H&K and He i D3 monitoring identifies the same main periodicity as the photometry but dynamic spectra also indicate that there is an intermittent dependence on the orbital period, in particular for Ca ii H&K in 2008. Line-profile inversions of a pair of Zeeman sensitive/insensitive iron lines yield an average surface magnetic-flux density of 542 ± 72 G. The time series for 2008 is modulated by the stellar rotation as well as the orbital motion, such that the magnetic flux is generally weaker during times of periastron and that the chromospheric emissions vary in anti-phase with the magnetic flux. We also identify a broad and asymmetric lithium line profile and measure an abundance of log n(Li) = 1.70 ± 0.05. The star

  13. Rotation, activity, and lithium abundance in cool binary stars

    NASA Astrophysics Data System (ADS)

    Strassmeier, K. G.; Weber, M.; Granzer, T.; Järvinen, S.

    2012-10-01

    We have used two robotic telescopes to obtain time-series high-resolution optical echelle spectroscopy and V I and/or by photometry for a sample of 60 active stars, mostly binaries. Orbital solutions are presented for 26 double-lined systems and for 19 single-lined systems, seven of them for the first time but all of them with unprecedented phase coverage and accuracy. Eighteen systems turned out to be single stars. The total of 6609 {R=55 000} échelle spectra are also used to systematically determine effective temperatures, gravities, metallicities, rotational velocities, lithium abundances and absolute Hα-core fluxes as a function of time. The photometry is used to infer unspotted brightness, {V-I} and/or b-y colors, spot-induced brightness amplitudes and precise rotation periods. An extra 22 radial-velocity standard stars were monitored throughout the science observations and yield a new barycentric zero point for our STELLA/SES robotic system. Our data are complemented by literature data and are used to determine rotation-temperature-activity relations for active binary components. We also relate lithium abundance to rotation and surface temperature. We find that 74 % of all known rapidly-rotating active binary stars are synchronized and in circular orbits but 26 % (61 systems) are rotating asynchronously of which half have {P_rot>P_orb} and {e>0}. Because rotational synchronization is predicted to occur before orbital circularization active binaries should undergo an extra spin-down besides tidal dissipation. We suspect this to be due to a magnetically channeled wind with its subsequent braking torque. We find a steep increase of rotation period with decreasing effective temperature for active stars, P_rot ∝ T_eff-7, for both single and binaries, main sequence and evolved. For inactive, single giants with {P_rot>100} d, the relation is much weaker, {P_rot ∝ T_eff-1.12}. Our data also indicate a period-activity relation for Hα of the form {R_Hα ∝ P

  14. A System Dynamics Modeling of Water Supply and Demand in Las Vegas Valley

    NASA Astrophysics Data System (ADS)

    Parajuli, R.; Kalra, A.; Mastino, L.; Velotta, M.; Ahmad, S.

    2017-12-01

    The rise in population and change in climate have posed the uncertainties in the balance between supply and demand of water. The current study deals with the water management issues in Las Vegas Valley (LVV) using Stella, a system dynamics modeling software, to model the feedback based relationship between supply and demand parameters. Population parameters were obtained from Center for Business and Economic Research while historical water demand and conservation practices were modeled as per the information provided by local authorities. The water surface elevation of Lake Mead, which is the prime source of water supply to the region, was modeled as the supply side whereas the water demand in LVV was modeled as the demand side. The study was done from the period of 1989 to 2049 with 1989 to 2012 as the historical one and the period from 2013 to 2049 as the future period. This study utilizes Coupled Model Intercomparison Project data sets (2013-2049) (CMIP3&5) to model different future climatic scenarios. The model simulates the past dynamics of supply and demand, and then forecasts the future water budget for the forecasted future population and future climatic conditions. The results can be utilized by the water authorities in understanding the future water status and hence plan suitable conservation policies to allocate future water budget and achieve sustainable water management.

  15. Modeling phytoremediation of nitrogen-polluted water using water hyacinth (Eichhornia crassipes)

    NASA Astrophysics Data System (ADS)

    Mayo, Aloyce W.; Hanai, Emmanuel E.

    2017-08-01

    Water hyacinth (Eichhornia crassipes) has a great potential for purification of wastewater through physical, chemical and biological mechanisms. In an attempt to improve the quality of effluents discharged from waste stabilization ponds at the University of Dar es Salaam, a pilot plant was constructed to experiment the effectiveness of this plants for transformation and removal of nitrogen. Samples of wastewater were collected and examined for water quality parameters, including pH, temperature, dissolved oxygen, and various forms of nitrogen, which were used as input parameters in a kinetic mathematical model. A conceptual model was then developed to model various processes in the system using STELLA 6.0.1 software. The results show that total nitrogen was removed by 63.9%. Denitrification contributed 73.8% of the removed nitrogen. Other dominant nitrogen removal mechanisms are net sedimentation and uptake by water hyacinth, which contributed 16.7% and 9.5% of the removed nitrogen, respectively. The model indicated that in presence of water hyacinth biofilm about 1.26 g Nm-2day-1 of nitrogen was removed. However, in the absence of biofilm in water hyacinth pond, the permanent nitrogen removal was only 0.89 g Nm-2day-1. This suggests that in absence of water hyacinth, the efficiency of nitrogen removal would decrease by 29.4%.

  16. A mediated modelling approach to promote collaborative learning in Andean rural micro-catchments in Colombia

    NASA Astrophysics Data System (ADS)

    Gowing, John; Dominguez, Isabel

    2013-04-01

    In rural catchments of developing countries water-related diseases, due to land use patterns (agriculture and livestock), microbial pollution, inadequate sanitation systems, access to water of poor quality, and lack of institutional support are common problems which disproportionally affect poor and vulnerable people. This research aims at developing a system dynamic model to improve the understanding of the macro and micro factors that influence human health and environmental health in rural micro-catchments in Valle del Cauca, Colombia. In this catchment livelihoods for most people depend on agriculture, particularly coffee. The research uses a mediated modeling approach, in which different stakeholders in modeling sessions, develop a STELLA model that allows them to identify relations between the economic, social and environmental factors and driving forces over the performance of their system. Stakeholders jointly develop the model structure in sessions facilitated by the researcher and the data required is gathered using secondary information from the different relevant institutions and primary information from field surveys that cover socioeconomic and environmental aspects that has not been previously collected by any institution or organization (i.e. household survey, stream water survey, and drinking water survey). Representation and understanding of their system will allow the stakeholders to test the effect of different management strategies in the micro-catchment and their associated socioeconomic, environmental and human health outcomes.

  17. A hybrid system dynamics and optimization approach for supporting sustainable water resources planning in Zhengzhou City, China

    NASA Astrophysics Data System (ADS)

    Li, Zhi; Li, Chunhui; Wang, Xuan; Peng, Cong; Cai, Yanpeng; Huang, Weichen

    2018-01-01

    Problems with water resources restrict the sustainable development of a city with water shortages. Based on system dynamics (SD) theory, a model of sustainable utilization of water resources using the STELLA software has been established. This model consists of four subsystems: population system, economic system, water supply system and water demand system. The boundaries of the four subsystems are vague, but they are closely related and interdependent. The model is applied to Zhengzhou City, China, which has a serious water shortage. The difference between the water supply and demand is very prominent in Zhengzhou City. The model was verified with data from 2009 to 2013. The results show that water demand of Zhengzhou City will reach 2.57 billion m3 in 2020. A water resources optimization model is developed based on interval-parameter two-stage stochastic programming. The objective of the model is to allocate water resources to each water sector and make the lowest cost under the minimum water demand. Using the simulation results, decision makers can easily weigh the costs of the system, the water allocation objectives, and the system risk. The hybrid system dynamics method and optimization model is a rational try to support water resources management in many cities, particularly for cities with potential water shortage and it is solidly supported with previous studies and collected data.

  18. The molecular characterization of porcine egg precursor cells

    PubMed Central

    Tsai, Te-Sha; Johnson, Jacqueline; White, Yvonne; John, Justin C.

    2017-01-01

    Female-factor infertility can be caused by poor oocyte quality and depleted ovarian reserves. Egg precursor cells (EPCs), isolated from the ovarian cortex, have the potential to be used to overcome female infertility. We aimed to define the origins of EPCs by analyzing their gene expression profiles and mtDNA content using a mini-pig model. We characterized FAC-sorted DDX4+-derived porcine EPCs by performing RNA-sequencing and determined that they utilize pathways important for cell cycle and proliferation, which supports the existence of adult mitotically active oogonial cells. Expression of the pluripotent markers Sox2 and Oct4, and the primitive germ cell markers Blimp1 and Stella were not detected. However, Nanog and Ddx4 were expressed, as were the primitive germ cell markers Fragilis, c-Kit and Tert. Moreover, porcine EPCs expressed self-renewal and proliferation markers including Myc, Esrrb, Id2, Klf4, Klf5, Stat3, Fgfr1, Fgfr2 and Il6st. The presence of Zp1, Zp2, Zp3 and Nobox were not detected, indicating that porcine EPCs are not indicative of mature primordial oocytes. We performed mitochondrial DNA Next Generation Sequencing and determined that one mtDNA variant harbored by EPCs was present in oocytes, preimplantation embryos and somatic tissues over three generations in our mini-pig model indicating the potential germline origin of EPCs. PMID:28969006

  19. Developing a Serious Game for decision making for the water-land-food-energy-climate Nexus in Sardinia-Italy: The SIM4NEXUS approach

    NASA Astrophysics Data System (ADS)

    Vamvakeridou-Lyroudia, Lydia; Alexandri, Eva; Blanco, Maria; Chew, Chengzi; Conradt, Tobias; Daskalou, Olympia; Evans, Barry; Guitart, Francesc; Mereu, Simone; Sartori, Martina; Susnik, Janez; Savic, Dragan

    2017-04-01

    downscaling HADGEM2 models - http://www.metoffice.gov.uk/research/modelling-systems/unified-model/climate-models/hadgem2); (iii) socio-economic inputs and projections (GTAP - http://en.openei.org/wiki/Global_Trade_and_Analysis_Project_(GTAP)_Model) with System Dynamic Modelling (SDM) using STELLA for the visual environment- http://www.iseesystems.com/store/products/stella-professional.aspx and STELLAR as an open source programming language - http://www.r-gis.net/stellar/); (iv) creating a Knowledge Elicitation Engine (KEE), providing nexus semantics to the outputs of the SDM and (v) generating knowledge from Serious Game user interaction. Local data from Sardinian experts and stakeholders are being used in the pilot, which has been developed with their participation. The presentation will show results from sample scenarios and the approach to simulating uncertainties using SDM, as well as the overall data transfer and management scheme. It should be pointed out that the process of linking thematic models to System Dynamics (Complexity Science Modelling) and creating a KEE out of this combination is, to the best of our knowledge, novel and does not exist in the literature.

  20. Weekly Solutions of Time-Variable Gravity from 1993 to 2010

    NASA Technical Reports Server (NTRS)

    Lemoine, F.; Chinn, D.; Le Bail, K.; Zelensky, N.; Melachroinos, S.; Beall, J.

    2011-01-01

    The GRACE mission has been highly successful in determining the time-variable gravity field of the Earth, producing monthly or even more frequent solutions (cf. 10-day) solutions using both spherical harmonics and mascons. However the GRACE time series only commences in 2002 - 2003 and a gap of several years may occur in the series before a GRACE follow-on satellite is launched. Satellites tracked by SLR and DORIS have also been used to study time variations in the Earth's gravitational field. These include (most recently) the solutions of Cox and Chao (2002), Cheng et al. (2004, 2007) and Lemoine et al. (2007). In this paper we discuss the development of a new time series of low degree spherical harmonic fields based on the available SLR, DORIS and GPS data. We develop simultaneous solutions for both the geocenter and the low degree harmonics up to 5x5. The solutions integrate data from SLR geodetic satellites (e.g., Lageos1, Lageos2, Starlette, Stella, Ajisai, Larets, Westpac), altimetry satellites (TOPEX/Poseidon, Envisat, Jason-1, Jason-2), and satellites tracked solely by DORIS (e.g. SPOT2-5). We discuss some pertinent aspects of the satellite-specific modeling. We include altimeter crossovers in the weekly solutions where feasible and time permits. The resulting geocenter time series is compared with geophysical model predictions and other independently-derived solutions. Over the GRACE time period the fidelity and consistency with the GRACE solutions are presented.

  1. In Vivo Predictive Dissolution: Comparing the Effect of Bicarbonate and Phosphate Buffer on the Dissolution of Weak Acids and Weak Bases.

    PubMed

    Krieg, Brian J; Taghavi, Seyed Mohammad; Amidon, Gordon L; Amidon, Gregory E

    2015-09-01

    Bicarbonate is the main buffer in the small intestine and it is well known that buffer properties such as pKa can affect the dissolution rate of ionizable drugs. However, bicarbonate buffer is complicated to work with experimentally. Finding a suitable substitute for bicarbonate buffer may provide a way to perform more physiologically relevant dissolution tests. The dissolution of weak acid and weak base drugs was conducted in bicarbonate and phosphate buffer using rotating disk dissolution methodology. Experimental results were compared with the predicted results using the film model approach of (Mooney K, Mintun M, Himmelstein K, Stella V. 1981. J Pharm Sci 70(1):22-32) based on equilibrium assumptions as well as a model accounting for the slow hydration reaction, CO2 + H2 O → H2 CO3 . Assuming carbonic acid is irreversible in the dehydration direction: CO2 + H2 O ← H2 CO3 , the transport analysis can accurately predict rotating disk dissolution of weak acid and weak base drugs in bicarbonate buffer. The predictions show that matching the dissolution of weak acid and weak base drugs in phosphate and bicarbonate buffer is possible. The phosphate buffer concentration necessary to match physiologically relevant bicarbonate buffer [e.g., 10.5 mM (HCO3 (-) ), pH = 6.5] is typically in the range of 1-25 mM and is very dependent upon drug solubility and pKa . © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

  2. Earth-System Scales of Biodiversity Variability in Shallow Continental Margin Seafloor Ecosystems

    NASA Astrophysics Data System (ADS)

    Moffitt, S. E.; White, S. M.; Hill, T. M.; Kennett, J.

    2015-12-01

    High-resolution paleoceanographic sedimentary sequences allow for the description of ecosystem sensitivity to earth-system scales of climate and oceanographic change. Such archives from Santa Barbara Basin, California record the ecological consequences to seafloor ecosystems of climate-forced shifts in the California Current Oxygen Minimum Zone (OMZ). Here we use core MV0508-20JPC dated to 735,000±5,000 years ago (Marine Isotope Stage 18) as a "floating window" of millennial-scale ecological variability. For this investigation, previously published archives of planktonic δ18O (Globigerina bulloides) record stadial and interstadial oscillations in surface ocean temperature. Core MV0508-20JPC is an intermittently laminated archive, strongly influenced by the California Current OMZ, with continuously preserved benthic foraminifera and discontinuously preserved micro-invertebrates, including ophiuroids, echinoderms, ostracods, gastropods, bivalves and scaphopods. Multivariate statistical approaches, such as ordinations and cluster analyses, describe climate-driven changes in both foraminiferal and micro-invertebrate assemblages. Statistical ordinations illustrate that the shallow continental margin seafloor underwent predictable phase-shifts in oxygenation and biodiversity across stadial and interstadial events. A narrow suite of severely hypoxic taxa characterized foraminiferal communities from laminated intervals, including Bolivina tumida, Globobulimina spp., and Nonionella stella. Foraminiferal communities from bioturbated intervals are diverse and >60% similar to each other, and they are associated with echinoderm, ostracod and mollusc fossils. As with climate shifts in the latest Quaternary, there is a sensitive benthic ecosystem response in mid-Pleistocene continental margins to climatically related changes in OMZ strength.

  3. A simulation for teaching the basic and clinical science of fluid therapy.

    PubMed

    Rawson, Richard E; Dispensa, Marilyn E; Goldstein, Richard E; Nicholson, Kimberley W; Vidal, Noni Korf

    2009-09-01

    The course "Management of Fluid and Electrolyte Disorders" is an applied physiology course taught using lectures and paper-based cases. The course approaches fluid therapy from both basic science and clinical perspectives. While paper cases provide a basis for application of basic science concepts, they lack key components of genuine clinical cases that, by nature, are diverse, change over time, and respond in unique ways to therapeutic interventions. We developed a dynamic model using STELLA software that simulates normal and abnormal fluid and electrolyte balance in the dog. Students interact, not with the underlying model, but with a user interface that provides sufficient data (skin turgor, chemistry panel, etc.) for the clinical assessment of patients and an opportunity for treatment. Students administer fluids and supplements, and the model responds in "real time," requiring regular reassessment and, potentially, adaptation of the treatment strategy. The level of success is determined by clinical outcome, including improvement, deterioration, or death. We expected that the simulated cases could be used to teach both the clinical and basic science of fluid therapy. The simulation provides exposure to a realistic clinical environment, and students tend to focus on this aspect of the simulation while, for the most part, ignoring an exploration of the underlying physiological basis for patient responses. We discuss how the instructor's expertise can provide sufficient support, feedback, and scaffolding so that students can extract maximum understanding of the basic science in the context of assessing and treating at the clinical level.

  4. System dynamic modeling: an alternative method for budgeting.

    PubMed

    Srijariya, Witsanuchai; Riewpaiboon, Arthorn; Chaikledkaew, Usa

    2008-03-01

    To construct, validate, and simulate a system dynamic financial model and compare it against the conventional method. The study was a cross-sectional analysis of secondary data retrieved from the National Health Security Office (NHSO) in the fiscal year 2004. The sample consisted of all emergency patients who received emergency services outside their registered hospital-catchments area. The dependent variable used was the amount of reimbursed money. Two types of model were constructed, namely, the system dynamic model using the STELLA software and the multiple linear regression model. The outputs of both methods were compared. The study covered 284,716 patients from various levels of providers. The system dynamic model had the capability of producing various types of outputs, for example, financial and graphical analyses. For the regression analysis, statistically significant predictors were composed of service types (outpatient or inpatient), operating procedures, length of stay, illness types (accident or not), hospital characteristics, age, and hospital location (adjusted R(2) = 0.74). The total budget arrived at from using the system dynamic model and regression model was US$12,159,614.38 and US$7,301,217.18, respectively, whereas the actual NHSO reimbursement cost was US$12,840,805.69. The study illustrated that the system dynamic model is a useful financial management tool, although it is not easy to construct. The model is not only more accurate in prediction but is also more capable of analyzing large and complex real-world situations than the conventional method.

  5. 2012 best practices for repositories collection, storage, retrieval, and distribution of biological materials for research international society for biological and environmental repositories.

    PubMed

    2012-04-01

    Third Edition [Formula: see text] [Box: see text] Printed with permission from the International Society for Biological and Environmental Repositories (ISBER) © 2011 ISBER All Rights Reserved Editor-in-Chief Lori D. Campbell, PhD Associate Editors Fay Betsou, PhD Debra Leiolani Garcia, MPA Judith G. Giri, PhD Karen E. Pitt, PhD Rebecca S. Pugh, MS Katherine C. Sexton, MBA Amy P.N. Skubitz, PhD Stella B. Somiari, PhD Individual Contributors to the Third Edition Jonas Astrin, Susan Baker, Thomas J. Barr, Erica Benson, Mark Cada, Lori Campbell, Antonio Hugo Jose Froes Marques Campos, David Carpentieri, Omoshile Clement, Domenico Coppola, Yvonne De Souza, Paul Fearn, Kelly Feil, Debra Garcia, Judith Giri, William E. Grizzle, Kathleen Groover, Keith Harding, Edward Kaercher, Joseph Kessler, Sarah Loud, Hannah Maynor, Kevin McCluskey, Kevin Meagher, Cheryl Michels, Lisa Miranda, Judy Muller-Cohn, Rolf Muller, James O'Sullivan, Karen Pitt, Rebecca Pugh, Rivka Ravid, Katherine Sexton, Ricardo Luis A. Silva, Frank Simione, Amy Skubitz, Stella Somiari, Frans van der Horst, Gavin Welch, Andy Zaayenga 2012 Best Practices for Repositories: Collection, Storage, Retrieval and Distribution of Biological Materials for Research INTERNATIONAL SOCIETY FOR BIOLOGICAL AND ENVIRONMENTAL REPOSITORIES (ISBER) INTRODUCTION T he availability of high quality biological and environmental specimens for research purposes requires the development of standardized methods for collection, long-term storage, retrieval and distribution of specimens that will enable their future use. Sharing successful strategies for accomplishing this goal is one of the driving forces for the International Society for Biological and Environmental Repositories (ISBER). For more information about ISBER see www.isber.org . ISBER's Best Practices for Repositories (Best Practices) reflect the collective experience of its members and has received broad input from other repository professionals. Throughout this document

  6. INTERLAYER MICROMECHANICS OF THE AORTIC HEART VALVE LEAFLET

    PubMed Central

    Buchanan, Rachel M.; Sacks, Michael S.

    2014-01-01

    While the mechanical behaviors of the fibrosa and ventricularis layers of the aortic valve (AV) leaflet are understood, little information exists on their mechanical interactions mediated by the GAG-rich central spongiosa layer. Parametric simulations of the interlayer interactions of the AV leaflets in flexure utilized a tri-layered finite element (FE) model of circumferentially oriented tissue sections to investigate inter-layer sliding hypothesized to occur. Simulation results indicated that the leaflet tissue functions as a tightly bonded structure when the spongiosa effective modulus was at least 25% that of the fibrosa and ventricularis layers. Novel studies that directly measured transmural strain in flexure of AV leaflet tissue specimens validated these findings. Interestingly, a smooth transmural strain distribution indicated that the layers of the leaflet indeed act as a bonded unit, consistent with our previous observations (Stella and Sacks, 2007) of a large number of transverse collagen fibers interconnecting the fibrosa and ventricularis layers. Additionally, when the tri-layered FE model was refined to match the transmural deformations, a layer-specific bimodular material model (resulting in four total moduli) accurately matched the transmural strain and moment-curvature relations simultaneously. Collectively, these results provide evidence, contrary to previous assumptions, that the valve layers function as a bonded structure in the low-strain flexure deformation mode. Most likely, this results directly from the transverse collagen fibers that bind the layers together to disable physical sliding and maintain layer residual stresses. Further, the spongiosa may function as a general dampening layer while the AV leaflets deforms as a homogenous structure despite its heterogeneous architecture. PMID:24292631

  7. Modules for Experiments in Stellar Astrophysics (MESA): Convective Boundaries, Element Diffusion, and Massive Star Explosions

    NASA Astrophysics Data System (ADS)

    Paxton, Bill; Schwab, Josiah; Bauer, Evan B.; Bildsten, Lars; Blinnikov, Sergei; Duffell, Paul; Farmer, R.; Goldberg, Jared A.; Marchant, Pablo; Sorokina, Elena; Thoul, Anne; Townsend, Richard H. D.; Timmes, F. X.

    2018-02-01

    We update the capabilities of the software instrument Modules for Experiments in Stellar Astrophysics (MESA) and enhance its ease of use and availability. Our new approach to locating convective boundaries is consistent with the physics of convection, and yields reliable values of the convective-core mass during both hydrogen- and helium-burning phases. Stars with M< 8 M⊙ become white dwarfs and cool to the point where the electrons are degenerate and the ions are strongly coupled, a realm now available to study with MESA due to improved treatments of element diffusion, latent heat release, and blending of equations of state. Studies of the final fates of massive stars are extended in MESA by our addition of an approximate Riemann solver that captures shocks and conserves energy to high accuracy during dynamic epochs. We also introduce a 1D capability for modeling the effects of Rayleigh-Taylor instabilities that, in combination with the coupling to a public version of the STELLA radiation transfer instrument, creates new avenues for exploring Type II supernova properties. These capabilities are exhibited with exploratory models of pair-instability supernovae, pulsational pair-instability supernovae, and the formation of stellar-mass black holes. The applicability of MESA is now widened by the capability to import multidimensional hydrodynamic models into MESA. We close by introducing software modules for handling floating point exceptions and stellar model optimization, as well as four new software tools - MESA-Web, MESA-Docker, pyMESA, and mesastar.org - to enhance MESA's education and research impact.

  8. Can pair-instability supernova models match the observations of superluminous supernovae?

    NASA Astrophysics Data System (ADS)

    Kozyreva, Alexandra; Blinnikov, S.

    2015-12-01

    An increasing number of so-called superluminous supernovae (SLSNe) are discovered. It is believed that at least some of them with slowly fading light curves originate in stellar explosions induced by the pair instability mechanism. Recent stellar evolution models naturally predict pair instability supernovae (PISNe) from very massive stars at wide range of metallicities (up to Z = 0.006, Yusof et al.). In the scope of this study, we analyse whether PISN models can match the observational properties of SLSNe with various light-curve shapes. Specifically, we explore the influence of different degrees of macroscopic chemical mixing in PISN explosive products on the resulting observational properties. We artificially apply mixing to the 250 M⊙ PISN evolutionary model from Kozyreva et al. and explore its supernova evolution with the one-dimensional radiation hydrodynamics code STELLA. The greatest success in matching SLSN observations is achieved in the case of an extreme macroscopic mixing, where all radioactive material is ejected into the hydrogen-helium outer layer. Such an extreme macroscopic redistribution of chemicals produces events with faster light curves with high photospheric temperatures and high photospheric velocities. These properties fit a wider range of SLSNe than non-mixed PISN model. Our mixed models match the light curves, colour temperature, and photospheric velocity evolution of two well-observed SLSNe PTF12dam and LSQ12dlf. However, these models' extreme chemical redistribution may be hard to realize in massive PISNe. Therefore, alternative models such as the magnetar mechanism or wind-interaction may still to be favourable to interpret rapidly rising SLSNe.

  9. Benign endometrial proliferations mimicking malignancies: a review of problematic entities in small biopsy specimens.

    PubMed

    Ip, Philip Pun-Ching

    2018-02-14

    Benign proliferations that mimic malignancies are commonly encountered during the course of assessment of small and fragmented endometrial samples. Although benign, endometrial epithelial metaplasias often coexist with premalignant or malignant lesions causing diagnostic confusion. The difficulty with mucinous metaplasia lies in its distinction from atypical mucinous glandular proliferations and mucinous carcinomas, which are associated with significant interobserver variability. Papillary proliferation of the endometrium is commonly associated with hormonal drugs and endometrial polyps and is characterised by papillae with fibrovascular cores covered by epithelial cells without cytologic atypia. They are classified into simple or complex papillary proliferations depending on the architectural complexity and extent of proliferation. Complex papillary proliferations are associated with a high risk of concurrent or subsequent hyperplasia with atypia/carcinoma. Papillary proliferations may have coexisting epithelial metaplasias and, most commonly, mucinous metaplasia and syncytial papillary change. Those with striking mucinous metaplasia overlap morphologically with papillary mucinous metaplasia. The latter has been proposed as a precursor of endometrial mucinous carcinoma. Misinterpreting the Arias-Stella reaction as a malignant or premalignant lesion is more likely to occur if the pathologist is unaware that the patient is pregnant or on hormonal drugs. Endometrial hyperplasia with secretory changes may occasionally be difficult to distinguish from the torturous and crowded glands of a late secretory endometrium. Endometrial polyps may have abnormal features that can be misinterpreted as endometrial hyperplasia or Mullerian adenosarcoma. Awareness of these benign endometrial proliferations and their common association with hormonal medication or altered endogenous hormonal levels will help prevent the over-diagnosis of premalignant and malignant lesions.

  10. Real-world evidence for the safety of ipragliflozin in elderly Japanese patients with type 2 diabetes mellitus (STELLA-ELDER): final results of a post-marketing surveillance study.

    PubMed

    Yokote, Koutaro; Terauchi, Yasuo; Nakamura, Ichiro; Sugamori, Haruko

    2016-10-01

    To investigate the real-world safety of ipragliflozin in elderly Japanese patients with type 2 diabetes mellitus (T2DM). Japanese patients (≥65 years old) who were first prescribed ipragliflozin within 3 months after its launch in April 2014 were registered in this post-marketing surveillance (PMS). Final data collection was in July 2015. Survey items included demographics, treatments, adverse drug reactions (ADRs), vital signs, and laboratory variables. The PMS included 8505 patients (4181 males/4324 females). The mean age and diabetes duration were 72.3 years and 10.6 years, respectively. In 84.3% of patients, ipragliflozin was prescribed at 50 mg/day, which was continued unchanged. Overall, 16.91% of patients experienced 1880 ADRs, and 165 ADRs were classified as serious in 127 patients (1.49%). ADRs of special interest included skin complications, volume depletion, polyuria/pollakiuria, genital infection, urinary tract infection, renal disorders, hypoglycemia, cerebrovascular disease, cardiovascular disease, malignant tumor, fracture, and ketone body-related events. This 1-year PMS revealed probable ADRs in elderly Japanese patients with T2DM prescribed ipragliflozin in real-world settings, with no new safety concerns. The risk factors for ADRs varied but could be rationalized. The results should help physicians to identify possible treatment-emergent ADRs in ipragliflozin-treated patients.

  11. A Quantitative Dynamic Simulation of Bremia lactucae Airborne Conidia Concentration above a Lettuce Canopy.

    PubMed

    Fall, Mamadou Lamine; Van der Heyden, Hervé; Carisse, Odile

    2016-01-01

    Lettuce downy mildew, caused by the oomycete Bremia lactucae Regel, is a major threat to lettuce production worldwide. Lettuce downy mildew is a polycyclic disease driven by airborne spores. A weather-based dynamic simulation model for B. lactucae airborne spores was developed to simulate the aerobiological characteristics of the pathogen. The model was built using the STELLA platform by following the system dynamics methodology. The model was developed using published equations describing disease subprocesses (e.g., sporulation) and assembled knowledge of the interactions among pathogen, host, and weather. The model was evaluated with four years of independent data by comparing model simulations with observations of hourly and daily airborne spore concentrations. The results show an accurate simulation of the trend and shape of B. lactucae temporal dynamics of airborne spore concentration. The model simulated hourly and daily peaks in airborne spore concentrations. More than 95% of the simulation runs, the daily-simulated airborne conidia concentration was 0 when airborne conidia were not observed. Also, the relationship between the simulated and the observed airborne spores was linear. In more than 94% of the simulation runs, the proportion of the linear variation in the hourly-observed values explained by the variation in the hourly-simulated values was greater than 0.7 in all years except one. Most of the errors came from the deviation from the 1:1 line, and the proportion of errors due to the model bias was low. This model is the only dynamic model developed to mimic the dynamics of airborne inoculum and represents an initial step towards improved lettuce downy mildew understanding, forecasting and management.

  12. A Quantitative Dynamic Simulation of Bremia lactucae Airborne Conidia Concentration above a Lettuce Canopy

    PubMed Central

    Fall, Mamadou Lamine; Van der Heyden, Hervé; Carisse, Odile

    2016-01-01

    Lettuce downy mildew, caused by the oomycete Bremia lactucae Regel, is a major threat to lettuce production worldwide. Lettuce downy mildew is a polycyclic disease driven by airborne spores. A weather-based dynamic simulation model for B. lactucae airborne spores was developed to simulate the aerobiological characteristics of the pathogen. The model was built using the STELLA platform by following the system dynamics methodology. The model was developed using published equations describing disease subprocesses (e.g., sporulation) and assembled knowledge of the interactions among pathogen, host, and weather. The model was evaluated with four years of independent data by comparing model simulations with observations of hourly and daily airborne spore concentrations. The results show an accurate simulation of the trend and shape of B. lactucae temporal dynamics of airborne spore concentration. The model simulated hourly and daily peaks in airborne spore concentrations. More than 95% of the simulation runs, the daily-simulated airborne conidia concentration was 0 when airborne conidia were not observed. Also, the relationship between the simulated and the observed airborne spores was linear. In more than 94% of the simulation runs, the proportion of the linear variation in the hourly-observed values explained by the variation in the hourly-simulated values was greater than 0.7 in all years except one. Most of the errors came from the deviation from the 1:1 line, and the proportion of errors due to the model bias was low. This model is the only dynamic model developed to mimic the dynamics of airborne inoculum and represents an initial step towards improved lettuce downy mildew understanding, forecasting and management. PMID:26953691

  13. Effects of the Earth Albedo and Thermic Emissivity on Geodetic Satellite Trajectories: a Mean Model from 2000-2016 data sets.

    NASA Astrophysics Data System (ADS)

    Deleflie, Florent; Sammuneh, Muhammad Ali; Coulot, David; Pollet, Arnaud; Biancale, Richard; Capderou, Michel

    2017-04-01

    Part of the energy received on the Earth from the Sun is split into two components, a short wave component which corresponds to the visible emissivity of the Earth's surface (albedo), and the long wave part corresponding to the thermic emissivity (infrared wavelengths). These two components induce small non gravitational forces on the orbits of artificial satellites, towards the radial direction (mainly), that we are evaluating to derive a mean model. The first step to evaluate the mean amplitudes and periods of the generaetd perturbations consists in comparing post-fit adjustment of geodetic satellites to SLR data, in two dynamical models accounting or not accounting for empirical forces standing for such effects: the orbits of the geodetic satellite STARLETTE, Stella, Ajisai, Lageos 1 and Lageos 2 are carried out in such a way over the period 2000-2016, with the GINS GRGS orbit computation s/w. We then use three kinds of data sets to investigate the mean amplitudes of the perturbations, and to investigate features on regional spatial scales: (i) Stephens tables, (Stephens, 1980), ECMWF (European Centre for Medium-Range Weather Forecasts ) data sets (that are available at GRGS, Groupe de Recherche de Géodésie Spatiale, France), and CERES (Clouds and the Earth's Radiant Energy System) data sets (publickly available).We analyze what is the data set leading to the lowest residual level. Then, following an approach close to the one developed by Stephens, we propose a set of monthly grids that are averaged over the period 2000-2016, and that is evaluated through the orbit computation of the above-mentioned satellites.

  14. Vertical oxygen minimum zone oscillations since 20 ka in Santa Barbara Basin: A benthic foraminiferal community perspective

    NASA Astrophysics Data System (ADS)

    Moffitt, Sarah E.; Hill, Tessa M.; Ohkushi, Kenichi; Kennett, James P.; Behl, Richard J.

    2014-01-01

    we present a history of deoxygenation of upper intermediate waters during the last deglaciation from Santa Barbara Basin (SBB), based on quantitative analyses of benthic foraminiferal assemblages, from a new shallow piston core above basin sill depth (MV0811-15JC, 418 m), and previously described sequences in the deeper basin (MD02-2504, 481 m and MD02-2503, 570 m). We document a 152 m depth transect of benthic foraminiferal assemblages to extract changing community structure (density, diversity, and evenness) and improve paleoenvironmental interpretation of late Quaternary vertical oscillations in the upper boundary of the oxygen minimum zone (OMZ). Close interaction between changes in open margin OMZ and that of the restricted SBB is documented using these quantitative techniques. MV0811-15JC, while being unlaminated, contains strongly hypoxic foraminiferal assemblages (including species Bolivina tumida and Nonionella stella), coeval with preserved sediment laminations in the deeper cores. Last Glacial Maximum (LGM) assemblages across this transect contained oxic fauna and high diversity. At 14.7 ka, glacial termination IA, hypoxic benthic fauna appeared across the transect, recording hypoxic waters (<0.5 ml L-1) < 300 m from the ocean surface. Bølling/Allerød (B/A) assemblages uniquely stand out in the record, exhibited by low density, diversity, and evenness, and taxonomic composition reflecting extreme and stressful hypoxia and methane-rich environments. Younger Dryas assemblages were diverse and composed of oxic fauna, similar to LGM assemblages. Termination IB initiated another deoxygenation shift, followed by OMZ-associated faunal and density patterns. This analysis strengthens the quantitative assessment of oxygen concentrations involved in deglacial OMZ change and reveals the unexpected, remarkable shallowness of OMZ influence during the B/A.

  15. Human second trimester amniotic fluid cells are able to create embryoid body-like structures in vitro and to show typical expression profiles of embryonic and primordial germ cells.

    PubMed

    Antonucci, Ivana; Di Pietro, Roberta; Alfonsi, Melissa; Centurione, Maria Antonietta; Centurione, Lucia; Sancilio, Silvia; Pelagatti, Francesca; D'Amico, Maria Angela; Di Baldassarre, Angela; Piattelli, Adriano; Tetè, Stefano; Palka, Giandomenico; Borlongan, Cesar V; Stuppia, Liborio

    2014-01-01

    Human amniotic fluid-derived stem cells (AFSCs) represent a novel class of broadly multipotent stem cells sharing characteristics of both embryonic and adult stem cells. However, both the origin of these cells and their actual properties in terms of pluripotent differentiation potential are still debated. In order to verify the presence of features of pluripotency in human second trimester AFSCs, we have investigated the ability of these cells to form in vitro three-dimensional aggregates, known as embryoid bodies (EBs), and to express specific genes of embryonic stem cells (ESCs) and primordial germ cells (PGCs). EBs were obtained after 5 days of AFSC culture in suspension and showed positivity for alkaline phosphatase (AP) staining and for specific markers of pluripotency (OCT4 and SOX2). Moreover, EB-derived cells showed the expression of specific transcripts of the three germ layers. RT-PCR analysis, carried out at different culture times (second, third, fourth, fifth, and eighth passages), revealed the presence of specific markers of ESCs (such as FGF4 and DAPPA4), as well as of markers typical of PGCs and, in particular, genes involved in early stages of germ cell development (Fragilis, Stella, Vasa, c-Kit, Rnf17). Finally, the expression of genes related to the control of DNA methylation (DNMT3A, DNMT3b1, DNMT1, DNMT3L, MBD1, MBD2, MBD3, MDB4, MeCP2), as well as the lack of inactivation of the X-chromosome in female samples, was also demonstrated. Taken together, these data provide further evidence for the presence of common features among human AFSCs, PGCs, and ESCs.

  16. Fast and Luminous Transients from the Explosions of Long-lived Massive White Dwarf Merger Remnants

    NASA Astrophysics Data System (ADS)

    Brooks, Jared; Schwab, Josiah; Bildsten, Lars; Quataert, Eliot; Paxton, Bill; Blinnikov, Sergei; Sorokina, Elena

    2017-12-01

    We study the evolution and final outcome of long-lived (≈ {10}5 years) remnants from the merger of an He white dwarf (WD) with a more massive C/O or O/Ne WD. Using Modules for Experiments in Stellar Astrophysics ({\\mathtt{MESA}}), we show that these remnants have a red giant configuration supported by steady helium burning, adding mass to the WD core until it reaches {M}{core}≈ 1.12{--}1.20 {M}⊙ . At that point, the base of the surface convection zone extends into the burning layer, mixing the helium-burning products (primarily carbon and magnesium) throughout the convective envelope. Further evolution depletes the convective envelope of helium and dramatically slows the mass increase of the underlying WD core. The WD core mass growth re-initiates after helium depletion, as then an uncoupled carbon-burning shell is ignited and proceeds to burn the fuel from the remaining metal-rich extended envelope. For large enough initial total merger masses, O/Ne WD cores would experience electron-capture triggered collapse to neutron stars (NSs) after growing to near Chandrasekhar mass ({M}{Ch}). Massive C/O WD cores could suffer the same fate after a carbon-burning flame converts them to ONe. The NS formation would release ≈ {10}50 erg into the remaining extended low mass envelope. Using the STELLA radiative transfer code, we predict the resulting optical light curves from these exploded envelopes. Reaching absolute magnitudes of {M}V≈ -17, these transients are bright for about one week and have many features of the class of luminous, rapidly evolving transients studied by Drout and collaborators.

  17. Molecular assessment, characterization, and differentiation of theca stem cells imply the presence of mesenchymal and pluripotent stem cells in sheep ovarian theca layer.

    PubMed

    Adib, Samane; Valojerdi, Mojtaba Rezazadeh

    2017-10-01

    The ability of ovarian theca stem cells to differentiate into oocyte and theca cells may lead to a major advancement in reproductive biology and infertility treatments. However, there is little information about function, growth and differentiation potential of these immature cells. In this study adult sheep theca stem cells (TSCs) characteristics, and differentiation potential into osteocyte-like cells (OSLCs), adipocyte-like cells (ALCs), theca progenitor-like cells (TPCs), and oocyte-like cells (OLCs) were investigated. TSCs were isolated, cultured, and compared with mesenchymal stem cells (MSCs), fibroblast cells (FCs), and pluripotent embryonic ovarian cells (EO). Adherent TSCs were morphologically similar to FCs. Cell cycle analysis showed high proliferation capacity of TSCs. TSCs were positive for the mesenchymal cells surface markers, and also expressed POU5F1. Differentiation potential of TSCs into OSLCs and ALCs were confirmed by alizarin red and oil red staining respectively. OSTEOCALCIN and COL1 were expressed in OSLCs. ALCs were positive for PPARα and LPL. TPCs expressed theca specific genes (GLI2, GLI3, PTCH1, CYP17A1, 3β-HSD and LHR) and secreted testosterone, dehydroepiandrostenedione (DHEA), androstenedione, progesterone and estradiol. Lipid droplets in these steroid cells were viewed by oil red staining. OLCs expressed oocyte-specific marker genes including, ZP3, ZP2, GDF9, SYCP3, PRDM1, STELLA, FRAGILIS, DAZL, as well as POU5F1, and showed separated sphere structure. Our results indicated that TSCs derived from ovarian follicles contain MSCs and pluripotent stem cells (PSCs) that can be differentiated into lineages of mesenchymal origin and are capable of differentiation into TPCs and OLCs under in vitro conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Imprints and DPPA3 are bypassed during pluripotency- and differentiation-coupled methylation reprogramming in testicular germ cell tumors

    PubMed Central

    Killian, J. Keith; Dorssers, Lambert C.J.; Trabert, Britton; Gillis, Ad J.M.; Cook, Michael B.; Wang, Yonghong; Waterfall, Joshua J.; Stevenson, Holly; Smith, William I.; Noyes, Natalia; Retnakumar, Parvathy; Stoop, J. Hans; Oosterhuis, J. Wolter; Meltzer, Paul S.; McGlynn, Katherine A.; Looijenga, Leendert H.J.

    2016-01-01

    Testicular germ cell tumors (TGCTs) share germline ancestry but diverge phenotypically and clinically as seminoma (SE) and nonseminoma (NSE), the latter including the pluripotent embryonal carcinoma (EC) and its differentiated derivatives, teratoma (TE), yolk sac tumor (YST), and choriocarcinoma. Epigenomes from TGCTs may illuminate reprogramming in both normal development and testicular tumorigenesis. Herein we investigate pure-histological forms of 130 TGCTs for conserved and subtype-specific DNA methylation, including analysis of relatedness to pluripotent stem cell (ESC, iPSC), primordial germ cell (PGC), and differentiated somatic references. Most generally, TGCTs conserve PGC-lineage erasure of maternal and paternal genomic imprints and DPPA3 (also known as STELLA); however, like ESCs, TGCTs show focal recurrent imprinted domain hypermethylation. In this setting of shared physiologic erasure, NSEs harbor a malignancy-associated hypermethylation core, akin to that of a diverse cancer compendium. Beyond these concordances, we found subtype epigenetic homology with pluripotent versus differentiated states. ECs demonstrate a striking convergence of both CpG and CpH (non-CpG) methylation with pluripotent states; the pluripotential methyl-CpH signature crosses species boundaries and is distinct from neuronal methyl-CpH. EC differentiation to TE and YST entails reprogramming toward the somatic state, with loss of methyl-CpH but de novo methylation of pluripotency loci such as NANOG. Extreme methyl-depletion among SE reflects the PGC methylation nadir. Adjacent to TGCTs, benign testis methylation profiles are determined by spermatogenetic proficiency measured by Johnsen score. In sum, TGCTs share collective entrapment in a PGC-like state of genomic-imprint and DPPA3 erasure, recurrent hypermethylation of cancer-associated targets, and subtype-dependent pluripotent, germline, or somatic methylation. PMID:27803193

  19. Does Rubella Cause Autism: A 2015 Reappraisal?

    PubMed

    Hutton, Jill

    2016-01-01

    In the 1970s, Stella Chess found a high prevalence of autism in children with congenital rubella syndrome (CRS), 200 times that of the general population at the time. Many researchers quote this fact to add proof to the current theory that maternal infection with immune system activation in pregnancy leads to autism in the offspring. This rubella and autism association is presented with the notion that rubella has been eliminated in today's world. CRS cases are no longer typically seen; yet, autistic children often share findings of CRS including deafness, congenital heart defects, and to a lesser extent visual changes. Autistic children commonly have hyperactivity and spasticity, as do CRS children. Both autistic and CRS individuals may develop type 1 diabetes as young adults. Neuropathology of CRS infants may reveal cerebral vasculitis with narrowed lumens and cerebral necrosis. Neuroradiological findings of children with CRS show calcifications, periventricular leukomalacia, and dilated perivascular spaces. Neuroradiology of autism has also demonstrated hyperintensities, leukomalacia, and prominent perivascular spaces. PET studies of autistic individuals exhibit decreased perfusion to areas of the brain similarly affected by rubella. In both autism and CRS, certain changes in the brain have implicated the immune system. Several children with autism lack antibodies to rubella, as do children with CRS. These numerous similarities increase the probability of an association between rubella virus and autism. Rubella and autism cross many ethnicities in many countries. Contrary to current belief, rubella has not been eradicated and globally affects up to 5% of pregnant women. Susceptibility continues as vaccines are not given worldwide and are not fully protective. Rubella might still cause autism, even in vaccinated populations.

  20. Does Rubella Cause Autism: A 2015 Reappraisal?

    PubMed Central

    Hutton, Jill

    2016-01-01

    In the 1970s, Stella Chess found a high prevalence of autism in children with congenital rubella syndrome (CRS), 200 times that of the general population at the time. Many researchers quote this fact to add proof to the current theory that maternal infection with immune system activation in pregnancy leads to autism in the offspring. This rubella and autism association is presented with the notion that rubella has been eliminated in today’s world. CRS cases are no longer typically seen; yet, autistic children often share findings of CRS including deafness, congenital heart defects, and to a lesser extent visual changes. Autistic children commonly have hyperactivity and spasticity, as do CRS children. Both autistic and CRS individuals may develop type 1 diabetes as young adults. Neuropathology of CRS infants may reveal cerebral vasculitis with narrowed lumens and cerebral necrosis. Neuroradiological findings of children with CRS show calcifications, periventricular leukomalacia, and dilated perivascular spaces. Neuroradiology of autism has also demonstrated hyperintensities, leukomalacia, and prominent perivascular spaces. PET studies of autistic individuals exhibit decreased perfusion to areas of the brain similarly affected by rubella. In both autism and CRS, certain changes in the brain have implicated the immune system. Several children with autism lack antibodies to rubella, as do children with CRS. These numerous similarities increase the probability of an association between rubella virus and autism. Rubella and autism cross many ethnicities in many countries. Contrary to current belief, rubella has not been eradicated and globally affects up to 5% of pregnant women. Susceptibility continues as vaccines are not given worldwide and are not fully protective. Rubella might still cause autism, even in vaccinated populations. PMID:26869906

  1. Future trends in the supply and demand for radiation oncology physicists.

    PubMed

    Mills, Michael D; Thornewill, Judah; Esterhay, Robert J

    2010-04-12

    Significant controversy surrounds the 2012 / 2014 decision announced by the Trustees of the American Board of Radiology (ABR) in October of 2007. According to the ABR, only medical physicists who are graduates of a Commission on Accreditation of Medical Physics Education Programs, Inc. (CAMPEP) accredited academic or residency program will be admitted for examination in the years 2012 and 2013. Only graduates of a CAMPEP accredited residency program will be admitted for examination beginning in the year 2014. An essential question facing the radiation oncology physics community is an estimation of supply and demand for medical physicists through the year 2020. To that end, a Demand & Supply dynamic model was created using STELLA software. Inputs into the model include: a) projected new cancer incidence and prevalence 1990-2020; b) AAPM member ages and retirement projections 1990-2020; c) number of ABR physics diplomates 1990-2009; d) number of patients per Qualified Medical Physicist from Abt Reports I (1995), II (2002) and III (2008); e) non-CAMPEP physicists trained 1990-2009 and projected through 2014; f) CAMPEP physicists trained 1993-2008 and projected through 2014; and g) working Qualified Medical Physicists in radiation oncology in the United States (1990-2007). The model indicates that the number of qualified medical physicists working in radiation oncology required to meet demand in 2020 will be 150-175 per year. Because there is some elasticity in the workforce, a portion of the work effort might be assumed by practicing medical physicists. However, the minimum number of new radiation oncology physicists (ROPs) required for the health of the profession is estimated to be 125 per year in 2020. The radiation oncology physics community should plan to build residency programs to support these numbers for the future of the profession.

  2. GRACE RL03-v2 monthly time series of solutions from CNES/GRGS

    NASA Astrophysics Data System (ADS)

    Lemoine, Jean-Michel; Bourgogne, Stéphane; Bruinsma, Sean; Gégout, Pascal; Reinquin, Franck; Biancale, Richard

    2015-04-01

    Based on GRACE GPS and KBR Level-1B.v2 data, as well as on LAGEOS-1/2 SLR data, CNES/GRGS has published in 2014 the third full re-iteration of its GRACE gravity field solutions. This monthly time series of solutions, named RL03-v1, complete to spherical harmonics degree/order 80, has displayed interesting performances in terms of spatial resolution and signal amplitude compared to JPL/GFZ/CSR RL05. This is due to a careful selection of the background models (FES2014 ocean tides, ECMWF ERA-interim (atmosphere) and TUGO (non IB-ocean) "dealiasing" models every 3 hours) and to the choice of an original method for gravity field inversion : truncated SVD. Identically to the previous CNES/GRGS releases, no additional filtering of the solutions is necessary before using them. Some problems have however been identified in CNES/GRGS RL03-v1: - an erroneous mass signal located in two small circular rings close to the Earth's poles, leading to the recommendation not to use RL03-v1 above 82° latitudes North and South; - a weakness in the sectorials due to an excessive downweighting of the GRACE GPS observations. These two problems have been understood and addressed, leading to the computation of a corrected time series of solutions, RL03-v2. The corrective steps have been: - to strengthen the determination of the very low degrees by adding Starlette and Stella SLR data to the normal equations; - to increase the weight of the GRACE GPS observations; - to adopt a two steps approach for the computation of the solutions: first a Choleski inversion for the low degrees, followed by a truncated SVD solution. The identification of these problems will be discussed and the performance of the new time series evaluated.

  3. STENCIL: Science Teaching European Network for Creativity and Innovation in Learning

    NASA Astrophysics Data System (ADS)

    Cattadori, M.; Magrefi, F.

    2013-12-01

    STENCIL is an european educational project funded with support of the European Commission within the framework of LLP7 (Lifelong Learning Programme) for a period of 3 years (2011 - 2013). STENCIL includes 21 members from 9 European countries (Bulgaria, Germany, Greece, France, Italy, Malta, Portugal, Slovenia, Turkey.) working together to contribute to the general objective of improving science teaching, by promoting innovative methodologies and creative solutions. Among the innovative methods adept a particolar interest is a joint partnership between a wide spectrum of type of institutions such as schools, school authorities, research centres, universities, science museums, and other organizations, representing differing perspectives on science education. STENCIL offers to practitioners in science education from all over Europe, a platform; the web portal - www.stencil-science.eu - that provides high visibility to schools and institutions involved in Comenius and other similar European funded projects in science education. STENCIL takes advantage of the positive results achieved by the former European projects STELLA - Science Teaching in a Lifelong Learning Approach (2007 - 2009) and GRID - Growing interest in the development of teaching science (2004-2006). The specific objectives of the project are : 1) to identify and promote innovative practices in science teaching through the publication of Annual Reports on Science Education; 2) to bring together science education practitioners to share different experiences and learn from each other through the organisation of periodical study visits and workshops; 3) to disseminate materials and outcomes coming from previous EU funded projects and from isolated science education initiatives through the STENCIL web portal, as well as through international conferences and national events. This contribution aims at explaining the main features of the project together with the achieved results during the project's 3 year

  4. Higher education and children in immigrant families.

    PubMed

    Baum, Sandy; Flores, Stella M

    2011-01-01

    The increasing role that immigrants and their children, especially those from Latin America, are playing in American society, Sandy Baum and Stella Flores argue, makes it essential that as many young newcomers as possible enroll and succeed in postsecondary education. Immigrant youths from some countries find the doors to the nation's colleges wide open. But other groups, such as those from Latin America, Laos, and Cambodia, often fail to get a postsecondary education. Immigration status itself is not a hindrance. The characteristics of the immigrants, such as their country of origin, race, and parental socioeconomic status, in addition to the communities, schools, and legal barriers that greet them in the United States, explain most of that variation. Postsecondary attainment rates of young people who come from low-income households and, regardless of income or immigration status, whose parents have no college experience are low across the board. Exacerbating the financial constraints is the reality that low-income students and those whose parents have little education are frequently ill prepared academically to succeed in college. The sharp rise in demand for skilled labor over the past few decades has made it more urgent than ever to provide access to postsecondary education for all. And policy solutions, say the authors, require researchers to better understand the differences among immigrant groups. Removing barriers to education and to employment opportunities for undocumented students poses political, not conceptual, problems. Providing adequate funding for postsecondary education through low tuition and grant aid is also straightforward, if not easy to accomplish. Assuring that Mexican immigrants and others who grow up in low-income communities have the opportunity to prepare themselves academically for college is more challenging. Policies to improve the elementary and secondary school experiences of all children are key to improving the postsecondary

  5. Earth Futures: a General Education Sustainability Course at the Pennsylvania State University

    NASA Astrophysics Data System (ADS)

    Bralower, T. J.; Bice, D. M.; Barron, E. J.

    2012-12-01

    Earth in the Future: Predicting Climate Change and Its Impacts Over the Next Century has been taught at The Pennsylvania State University since 2000. The course is a general education course designed to give a broad survey of the science underlying climate change as well as the impacts on natural and human systems. The course has three major goals: (1) to provide an understanding of climate science and of the possible scenarios of how climate may change in the future; (2) to analyze the linkages between climate and major human and natural systems, including agriculture, water, ocean circulation, and coastal ecosystems, necessary to assess the potential impacts of climate change; and (3) to understand the potential responses to climate change, including both adaptation to, and mitigation of change. The general education course is the entry point for a new BS-degree program, Earth System Science and Policy (ESSP). Initially the course was taught face to face on a yearly basis. Recently we have developed an on-line version of the course, and, in Fall semester, 2012, we are teaching a revised version of the course face-to-face and on-line. Both versions of the course are being assessed using survey instruments developed for InTeGrate courses. The simultaneous instruction provides a unique opportunity to compare the strengths and weaknesses of the two different modes of education. From its beginning, the course has included laboratory exercises designed to enhance the student's understanding of climate science. The revised course includes laboratory exercises in every module, including STELLA-based model experiments. These exercises form an essential part of the on-line version of the course, however, the identical exercises are involved in the face-to-face version. In our presentation, we provide preliminary comparison of the two instructional modes as well as their effectiveness in recruiting students to the ESSP major.

  6. [The characters and specific features of new human embryonic stem cells lines].

    PubMed

    Krylova, T A; Kol'tsova, A M; Zenin, V V; Gordeeva, O F; Musorina, A S; Goriachaia, T S; Shlykova, S A; Kamenetskaia, Iu K; Pinaev, G P; Polianskaia, G G

    2009-01-01

    Four continuous human embryonic stem cell lines (SC1, SC2, SC3 and SC4), derived from the blastocysts has been described. The cell lines were cultivated on mitotically inactivated human feeder cells. The cell lines SC1 and SC2 have passed through 150 population doublings and the cell lines SC3 and SC4 -- near 120 populations doublings, which exceeds Hayflick limit sufficiently. These cell lines maintain high activity of alkaline phosphatase, expression of transcription factor OCT-4 and cell surface antigens (SSEA-4, TRA-1-60 and TRA-1-81), confirming their ESC status and human specificity. Immunofluorescent detection of antigens, characteristic of ectoderm, endoderm and mesoderm confirms the ability of these cells to retain their pluripotency under in vitro condition. PCR analysis revealed expression of six genes specific for pluripotent cells (OCT-4, NANOG, DPPA3/STELLA, TDGF/CRIPTO and LEFTYA). Correlation between the level of proliferative activity and the character of DNA-bound fluorescent staining was found. Fluorescent dyes, Hoechst 33342 and PI, produced diffuse staining of the nuclei in slowly proliferating cells of the SC1 and SC2 lines. In contrast, in actively proliferating cells of the SC3 and SC4 lines, the clear staining of the nuclei was observed. Upon changing the cultivation condition, proliferative activity of SC3 and SC4 lines decreased and became similar to that of SC1 and SC2 lines. The character of the fluorescent staining of all these lines was also shown to be similar. These results show that quality of the fluorescent staining with Hoechst 33342 and PI reflects the level of proliferation. Possible causes and mechanisms of this feature of human ESC are discussed.

  7. Response of benthic foraminifers to sewage discharge and remediation in Santa Monica Bay, California

    USGS Publications Warehouse

    McGann, M.; Alexander, C.R.; Bay, S.M.

    2003-01-01

    Examination of a time series of foraminiferal assemblage distributions on the continental shelf and slope of Santa Monica Bay from 1955 to 1997-1998 suggests that the benthic microfauna have been greatly affected by the quality and character of the municipal sludge and wastewater discharged into the bay over the last half-century by the Hyperion Treatment Plant serving the greater Los Angeles area. Five species dominate both the living and dead foraminiferal assemblages of the 1997-1998 surface samples, including Eggerella advena, Trochammina pacifica, Bulimina denudata, Buliminella elegantissima, and Epistominella bradyana. Temporal patterns of relative species abundances for both living and dead assemblages, as well as toxicity tests measuring amphipod survival and sea urchin fertilization success, show improvement since the sewage treatment program was enhanced in 1986. None of these trends are evident 10 years earlier, coincident with the onset of a Pacific Decadal Oscillation warming trend. This fact suggests that remediation, and not climate change, is responsible for the faunal changes observed. Even with remediation, however, all foraminiferal faunal trends have not returned to early-outfall levels. The organic-waste indicating species T. pacifica shows a slow decline in abundance as sewage treatment and sludge disposal activities have improved, whereas a dramatic increase in the abundance of the pioneer colonizer of impacted regions, E. advena, has occurred, often with a reciprocal response by B. denudata. Also evident is a dramatic shift in the abundance of the once-dominant species Nonionella basispinata and Nonionella stella, which were unable to recolonize Santa Monica Bay since the two major outfalls (5- and 7-mile) began discharging. Temporal variations in species abundances, as well as range expansions, contractions, and the inability to recolonize areas previously, or presently, impacted, suggests that foraminifers are a useful tool in defining

  8. Tidal tearing of circumstellar disks in Be/X-ray and gamma-ray binaries

    NASA Astrophysics Data System (ADS)

    Okazaki, Atsuo T.

    2017-11-01

    About one half of high-mass X-ray binaries host a Be star [an OB star with a viscous decretion (slowly outflowing) disk]. These Be/X-ray binaries exhibit two types of X-ray outbursts (Stella et al. 1986), normal X-ray outbursts (L X~1036-37 erg s-1) and occasional giant X-ray outbursts (L X > 1037 erg s-1). The origin of giant X-ray outbursts is unknown. On the other hand, a half of gamma-ray binaries have a Be star as the optical counterpart. One of these systems [LS I +61 303 (P orb = 26.5 d)] shows the superorbital (1,667 d) modulation in radio through X-ray bands. No consensus has been obtained for its origin. In this paper, we study a possibility that both phenomena are caused by a long-term, cyclic evolution of a highly misaligned Be disk under the influence of a compact object, by performing 3D hydrodynamic simulations. We find that the Be disk cyclically evolves in mildly eccentric, short-period systems. Each cycle consists of the following stages: 1) As the Be disk grows with time, the initially circular disk becomes eccentric by the Kozai-Lidov mechanism. 2) At some point, the disk is tidally torn off near the base and starts precession. 3) Due to precession, a gap opens between the disk base and mass ejection region, which allows the formation of a new disk in the stellar equatorial plane (see Figure 1). 4) The newly formed disk finally replaces the precessing old disk. Such a cyclic disk evolution has interesting implications for the long-term behavior of high energy emission in Be/X-ray and gamma-ray binaries.

  9. Investigation into the importance of the stomatal pathway in the exchange of PCBs between air and plants.

    PubMed

    Barber, Jonathan L; Kurt, Perihan B; Thomas, Gareth O; Kerstiens, Gerhard; Jones, Kevin C

    2002-10-15

    The transfer of persistent organic pollutants (POPs) from air to vegetation is an important air-surface exchange process that affects global cycling and can result in human and wildlife exposure via the terrestrial food chain. To improve understanding of this process, the role of stomata in uptake of gas-phase polychlorinated biphenyls (PCBs) was investigated using Hemerocallis x hybrida "Black Eyed Stella", a plant with a high stomatal density. Uptake of PCBs was monitored over a 72-h period in the presence and absence of light. Uptake rates were significantly greater in illuminated (stomata open) plants than unilluminated (stomata closed) plants for 18 of the 28 measured PCB congeners (p < 0.05). Depuration of PCBs was monitored in a subsequent experiment over a period of 3 weeks. Levels after 3 weeks of depuration time were still much higher than the concentration prior to contamination. Tri- and tetrachlorinated PCBs showed the greatest depuration, with less than 20% and 50% of accumulated PCBs respectively remaining, while approximately 70% of higher chlorinated PCB congeners remained in the plants at the end of the experiment. Treatments with/without light (to control stomatal opening during uptake) and with/without abscisic acid (ABA) application (to control stomatal opening during depuration) were compared. After contamination indoors for 3 days, there was a significantly higher concentration of PCBs (p < 0.05) in the light contaminated plants than the dark-contaminated plants for 13 of the 28 measured PCB congeners. The ABA treatment affected depuration of PCB-18 only. "Light/ABA-treated" plants had a significantly slower depuration rate for PCB-18 than "light/untreated", "dark/ABA-treated", and "dark/untreated" plants (p < 0.05). The results of the study indicate that there is a stomatal effect on the rate of exchange of PCBs between Hemerocallis leaves and air.

  10. Stellar activity cycles from long-term data by robotic telescopes

    NASA Astrophysics Data System (ADS)

    Oláh, K.

    2014-03-01

    All results about stellar activity cycles stem from decades-long systematic observations that were done by small telescopes. Without these equipments we would not know much, if anything, about stellar activity cycles, like those we see and observe easily on the nearest star, the Sun. In the early 80's of the last century systematic photometric monitoring of active stars began with automated photometric telescopes (APTs), some of which continue the observations to date. The Vienna-Potsdam APT now works for about two decades (Strassmeier et al. 1997), similarly to the 4-College Consortium APT (Dukes et al. 1995), while the Catania APT (Rodono et al. 2001) was closed down a few years ago. These small tools with the same setups for decades do not cost much and are relatively cheap to maintain. The longest continuous photometric datasets of a few objects from APTs span now over 30 years, which, together with earlier, manually-obtained data allow to study those activity cycles of stars which are in the order of 10 years or shorter: to be sure in the timescale of a cycle it should be observed repeatedly at least 2-3 times. The spectroscopic automated telescope STELLA (Strassmeier et al. 2004), built in the first decade of this century, measured already a few dozens of radial velocity curves for long-period binary stars and measured their activity levels (Strassmeier et al. 2012); these results can be gathered only by robotic telescopes. Only with STELLA it is possible to study the decades-long behavior of starspots on active giants with long rotational periods via Doppler Imaging. As the databases were growing it became clear that stars, just as the Sun, had multiple cycles. It was also found that stellar cycles showed systematic changes and that the cycle lengths correlated with the rotational periods of the stars. Extensive summaries of stellar activity cycles are found in Baliunas et al. (1995) using the Mt. Wilson Ca-index survey, and Oláh et al. (2009) based on

  11. Costs and benefits of trap-neuter-release and euthanasia for removal of urban cats in Oahu, Hawaii.

    PubMed

    Lohr, Cheryl A; Cox, Linda J; Lepczyk, Christopher A

    2013-02-01

    Our goal was to determine whether it is more cost-effective to control feral cat abundance with trap-neuter-release programs or trap and euthanize programs. Using STELLA 7, systems modeling software, we modeled changes over 30 years in abundance of cats in a feral colony in response to each management method and the costs and benefits associated with each method . We included costs associated with providing food, veterinary care, and microchips to the colony cats and the cost of euthanasia, wages, and trapping equipment in the model. Due to a lack of data on predation rates and disease transmission by feral cats the only benefits incorporated into the analyses were reduced predation on Wedge-tailed Shearwaters (Puffinus pacificus). When no additional domestic cats were abandoned by owners and the trap and euthanize program removed 30,000 cats in the first year, the colony was extirpated in at least 75% of model simulations within the second year. It took 30 years for trap-neuter-release to extirpate the colony. When the cat population was supplemented with 10% of the initial population size per year, the colony returned to carrying capacity within 6 years and the trap and euthanize program had to be repeated, whereas trap-neuter-release never reduced the number of cats to near zero within the 30-year time frame of the model. The abandonment of domestic cats reduced the cost effectiveness of both trap-neuter-release and trap and euthanize. Trap-neuter-release was approximately twice as expensive to implement as a trap and euthanize program. Results of sensitivity analyses suggested trap-neuter-release programs that employ volunteers are still less cost-effective than trap and euthanize programs that employ paid professionals and that trap-neuter-release was only effective when the total number of colony cats in an area was below 1000. Reducing the rate of abandonment of domestic cats appears to be a more effective solution for reducing the abundance of feral cats.

  12. Modelling nitrogen transformation and removal in mara river basin wetlands upstream of lake Victoria

    NASA Astrophysics Data System (ADS)

    Mayo, Aloyce W.; Muraza, Marwa; Norbert, Joel

    2018-06-01

    Lake Victoria, the largest lake in Africa, is a resource of social-economic potential in East Africa. This lake receives water from numerous tributaries including Mara River, which contributes about 4.8% of the total Lake water inflow. Unfortunately, Mara River basin faces environmental problems because of intensive settlement, agriculture, overgrazing in the basin and mining activities, which has lead to water pollution in the river, soil erosion and degradation, decreased soil fertility, loss of vegetation cover, decreased water infiltration capacity and increased sedimentation. One of the pollutants carried by the river includes nitrogen, which has contributed to ecological degradation of the Lake Victoria. Therefore this research work was intended to determine the effectiveness of Mara River wetland for removal of nitrogen and to establish nitrogen removal mechanisms in the wetland. To predict nitrogen removal in the wetland, the dynamics of nitrogen transformation was studied using a conceptual numerical model that takes into account of various processes in the system using STELLA II version 9.0®2006 software. Samples of model input from water, plants and sediments were taken for 45 days and were analyzed for pH, temperature, and DO in situ and chemical parameters such as NH3-N, Org-N, NO2-N, and NO3-N were analyzed in the laboratory in accordance with Standard methods. For plants, the density, dominance, biomass productivity and TN were determined and for sediments TN was analyzed. Inflow into the wetland was determined using stage-discharge relationship and was found to be 734,400 m3/day and the average wetland volume was 1,113,500 m3. Data collected by this study were used for model calibration of nitrogen transformation in this wetland while data from another wetland were used for model validation. It was found that about 37.8% of total nitrogen was removed by the wetland system largely through sedimentation (26.6%), plant uptake (6.6%) and

  13. The ability of two commercially available quick test kits to detect drug-facilitated sexual assault drugs in beverages.

    PubMed

    Beynon, C M; Sumnall, H R; McVeigh, J; Cole, J C; Bellis, M A

    2006-10-01

    Assessment of the sensitivity and specificity of two commercially available 'drug-facilitated sexual assault' drug detector kits, Drink Guard and Drink Detective. Experimental. Laboratory. Gamma hydroxybutyrate (GHB) sodium salt, ketamine hydrochloride, temazepam, flunitrazepam and diazepam were dissolved (Tween added to benzodiazepine solutions) as separate stock solutions and added to 330 ml samples of cola (Pepsi Max), beer (Stella Artois), 'alcopop' (Bacardi Breezer) and placebo (distilled water). The doses used are reported to be common in cases of intoxication. Each kit was tested 10 times for each drink/drug combination. Two blind, independent observers scored each test (presence/absence of drug) in accordance with kit instructions; chi 2 was used to compare the proportion of times raters scored tests correctly and incorrectly. Sensitivity and specificity were calculated overall, for each drink, and sensitivity was calculated for each drug. Inter-observer agreement was evaluated using the kappa statistic. While both raters were able to score significantly more tests correctly than incorrectly using Drink Detective, and one rater scored similarly using Drink Guard, the overall sensitivity of Drink Detective and Drink Guard was 69.0% (95% CI 64.2-73.5%) and 37.5% (95% CI 30.1-45.5%), respectively. Sensitivity was drink-dependent. Drink Detective was unable to detect our dose of GHB in water, with all tests scored negatively by both raters for this drink/drug combination (n = 20 negative scores). Overall, specificity was 76.6% (95% CI 71.5-81.0%) and 87.9% (95% CI 83.0-91.6%) for Drink Guard and Drink Detective, respectively, but was affected by the beverage. Inter-rater agreement was poor for Drink Guard (kappa = 0.278 +/- 0.069) but excellent for Drink Detective (kappa = 0.894 +/- 0.245). Inter-observer agreement was drug-dependent. Use of drug detector kits by the public in the night-time environment needs further investigation and may create a false sense

  14. Very small embryonic-like stem cells (VSELs) detected in azoospermic testicular biopsies of adult survivors of childhood cancer.

    PubMed

    Kurkure, Purna; Prasad, Maya; Dhamankar, Vandana; Bakshi, Ganesh

    2015-11-09

    Infertility is a known side-effect of oncotherapy in cancer survivors, and often compromises the quality of life. The present study was undertaken to detect very small embryonic-like stem cells (VSELs) in testicular biopsies from young adult survivors of childhood cancer who had azoospermia. VSELs have been earlier reported in human and mouse testes. They resist busulphan treatment in mice and potentially restore spermatogenesis when the somatic niche is restored by transplanting Sertoli or mesenchymal cells. VSELs also have the potential to differentiate into sperm in vitro. The study had clearance from Institutional review board (IRB). Seven azoospermic survivors of childhood cancer were included in the study after obtaining their informed consent. Semen analysis was done to confirm azoospermia prior to inclusion in the study. Testicular biopsies were performed at the Uro-oncology Unit of the hospital and then used for various studies to detect VSELs. Hematoxylin and Eosin stained tubular sections confirmed azoospermia and smears revealed the presence of very small, spherical VSELs with high nucleo-cytoplasmic ratio, in addition to the Sertoli cells. Immuno-localization studies on testicular smears showed that the VSELs were CD133+/CD45-/LIN-, expressed nuclear OCT-4, STELLA and cell surface SSEA-4. Pluripotent transcripts Oct-4A, Nanog and Sox-2 were detected in azoospermic samples whereas marked reduction was observed in germ cell markers Oct-4 and Boule. The present study demonstrates the presence of pluripotent VSELs in the testicular biopsy of azoospermic adult survivors of childhood cancer. It is likely that these persisting VSELs can restore spermatogenesis as demonstrated in mice studies. Therefore, pilot studies need to be undertaken using autologous mesenchymal cells with a hope to restore testicular function and fertility in cancer survivors. The results of this study assume a great significance in the current era, where cryopreservation of testicular

  15. An ex vivo investigation into the transurothelial permeability and bladder wall distribution of the nonsteroidal anti-inflammatory ketorolac.

    PubMed

    Williams, Nicholas A; Bowen, Jenna L; Al-Jayyoussi, Ghaith; Gumbleton, Mark; Allender, Chris J; Li, Jamie; Harrah, Tim; Raja, Aditya; Joshi, Hrishi B

    2014-03-03

    Transurothelial drug delivery continues to be an attractive treatment option for a range of urological conditions; however, dosing regimens remain largely empirical. Recently, intravesical delivery of the nonsteroidal anti-inflammatory ketorolac has been shown to significantly reduce ureteral stent-related pain. While this latest development provides an opportunity for advancing the management of stent-related pain, clinical translation will undoubtedly require an understanding of the rate and extent of delivery of ketorolac into the bladder wall. Using an ex vivo porcine model, we evaluate the urothelial permeability and bladder wall distribution of ketorolac. The subsequent application of a pharmacokinetic (PK) model enables prediction of concentrations achieved in vivo. Ketorolac was applied to the urothelium and a transurothelial permeability coefficient (Kp) calculated. Relative drug distribution into the bladder wall after 90 min was determined. Ketorolac was able to permeate the urothelium (Kp = 2.63 × 10(-6) cm s(-1)), and after 90 min average concentrations of 400, 141 and 21 μg g(-1) were achieved in the urothelium, lamina propria and detrusor respectively. An average concentration of 87 μg g(-1) was achieved across the whole bladder wall. PK simulations (STELLA) were then carried out, using ex vivo values for Kp and muscle/saline partition coefficient (providing an estimation of vascular clearance), to predict 90 min in vivo ketorolac tissue concentrations. When dilution of the drug solution with urine and vascular clearance were taken into account, a reduced ketorolac concentration of 37 μg g(-1) across the whole bladder wall was predicted. These studies reveal crucial information about the urothelium's permeability to agents such as ketorolac and the concentrations achievable in the bladder wall. It would appear that levels of ketorolac delivered to the bladder wall intravesically would be sufficient to provide an anti-inflammatory effect. The

  16. Dynamics associated with spontaneous differentiation of ovarian stem cells in vitro

    PubMed Central

    2014-01-01

    Background Recent studies suggest that ovarian germ line stem cells replenish oocyte-pool in adult stage, and challenge the central doctrine of ‘fixed germ cell pool’ in mammalian reproductive biology. Two distinct populations of spherical stem cells with high nucleo-cytoplasmic ratio have been recently identified in the adult mammalian ovary surface epithelium (OSE) including nuclear OCT-4A positive very small embryonic-like (VSELs) and cytoplasmic OCT-4 expressing ovarian germ stem cells (OGSCs). Three weeks culture of scraped OSE cells results in spontaneous differentiation of the stem cells into oocyte-like, parthenote-like, embryoid body-like structures and also embryonic stem cell-like colonies whereas epithelial cells attach and transform into a bed of mesenchymal cells. Present study was undertaken, to further characterize ovarian stem cells and to comprehend better the process of spontaneous differentiation of ovarian stem cells into oocyte-like structures in vitro. Methods Ovarian stem cells were enriched by immunomagnetic sorting using SSEA-4 as a cell surface marker and were further characterized. Stem cells and clusters of OGSCs (reminiscent of germ cell nests in fetal ovaries), were characterized by immuno-localization for stem and germ cell specific markers and spontaneous differentiation in OSE cultures was studied by live cell imaging. Results Differential expression of markers specific for pluripotent VSELs (nuclear OCT-4A, SSEA-4, CD133), OGSCs (cytoplasmic OCT-4) primordial germ cells (FRAGILIS, STELLA, VASA) and germ cells (DAZL, GDF-9, SCP-3) were studied. Within one week of culture, stem cells became bigger in size, developed abundant cytoplasm, differentiated into germ cells, revealed presence of Balbiani body-like structure (mitochondrial cloud) and exhibited characteristic cytoplasmic streaming. Conclusions Presence of germ cell nests, Balbiani body-like structures and cytoplasmic streaming extensively described during fetal ovary

  17. Short-term evolution and coexistence of spots, plages and flare activity on LQ Hydrae

    NASA Astrophysics Data System (ADS)

    Flores Soriano, M.; Strassmeier, K. G.

    2017-01-01

    Aims: We aim to study the short-term evolution of the chromospheric and photospheric activity of the young, single K2 dwarf LQ Hya. Methods: Four months of quasi-simultaneous spectroscopic and photometric observations were used to study the variations of the photometric light curve, the evolution of the chromospheric activity from the Hα and Hβ lines, and the distribution of cool spots from Doppler maps. Results: During our observations one side of the star was more active than the other. The equivalent width of the Hα line from the least active hemisphere increased from ≈0.7 Å at the beginning of the observation to 1.0 Å at the end. The basal emission of the most active hemisphere remained roughly constant at EWHαt1.0 Å. Intense flare activity was observed during the first twenty days, where at least four different events were detected. The line asymmetries of the Hα line suggest that one of the flares could have produced a mass ejection with a maximum projected speed of 70kms-1. The rotational modulation of the V-band photometry showed clear anti-correlation with the chromospheric activity. The difference in brightness between the opposite hemispheres decreased from 0.m16 to 0.m09 in two months. Three spots gradually moving apart from each other are dominating the photospheric Doppler maps. The comparison between the maps and the Hα line as the star rotates reveals the spatial coexistence of chromospheric Hα emission and photospheric spots. Conclusions: Our results indicate that the active regions of LQ Hya can live for at least four months. The detected changes in the photometric light curve and the spectroscopic Doppler images seem to be more a consequence of the spatial redistribution of the active regions rather than due to changes in their strength. Only one of the active regions shows significant changes in its chromospheric emission. Based on data obtained with the STELLA robotic telescope in Tenerife, an AIP facility jointly operated by AIP

  18. The spectroscopic orbit of Capella revisited

    NASA Astrophysics Data System (ADS)

    Weber, M.; Strassmeier, K. G.

    2011-07-01

    Context. Capella is among the few binary stars with two evolved giant components. The hotter component is a chromospherically active star within the Hertzsprung gap, while the cooler star is possibly helium-core burning. Aims: The known inclination of the orbital plane from astrometry in combination with precise radial velocities will allow very accurate masses to be determined for the individual Capella stars. This will constrain their evolutionary stage and possibly the role of the active star's magnetic field on the dynamical evolution of the binary system. Methods: We obtained a total of 438 high-resolution échelle spectra during the years 2007-2010 and used the measured velocities to recompute the orbital elements. Our double-lined orbital solution yields average residuals of 64 m s-1 for the cool component and 297 m s-1 for the more rapidly rotating hotter component. Results: The semi-amplitude of the cool component is smaller by 0.045 km s-1 than the orbit determination of Torres et al. from data taken during 1996-1999 but more precise by a factor of 5.5, while for the hotter component it is larger by 0.580 km s-1 and more precise by a factor of 3.6. This corresponds to masses of 2.573 ± 0.009 M⊙ and 2.488 ± 0.008 M⊙ for the cool and hot component, respectively. Their relative errors of 0.34% and 0.30% are about half of the values given in Torres et al. for a combined literature-data solution but with absolute values different by 4% and 2% for the two components, respectively. The mass ratio of the system is therefore q = MA/MB = 0.9673 ± 0.0020. Conclusions: Our orbit is the most precise and also likely to be the most accurate ever obtained for Capella. Based on data obtained with the STELLA robotic telescope in Tenerife, an AIP facility jointly operated by AIP and IAC.Full Table 1 is only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/531/A89

  19. The Principal Forces of Oocyte Polarity Are Evolutionary Conserved but May Not Affect the Contribution of the First Two Blastomeres to the Blastocyst Development in Mammals

    PubMed Central

    Hosseini, Sayyed-Morteza; Moulavi, Fariba; Tanhaie-Vash, Nima; Asgari, Vajihe; Ghanaei, Hamid-Reza; Abedi-Dorche, Maryam; Jafarzadeh, Naser; Gourabi, Hossein; Shahverdi, Abdol-Hossein; Dizaj, Ahmad Vosough; Shirazi, Abolfazl; Nasr-Esfahani, Mohammad-Hossein

    2016-01-01

    Oocyte polarity and embryonic patterning are well-established features of development in lower species. Whether a similar form of pre-patterning exists in mammals is currently under hot debate in mice. This study investigated this issue for the first time in ovine as a large mammal model. Microsurgical trisection of unfertilized MII-oocytes revealed that cortical cytoplasm around spindle (S) contained significant amounts of total maternal mRNAs and proteins compared to matched cytoplast hemispheres that were located either near (NS) or far (FS) -to-spindle. RT-qPCR provided striking examples of maternal mRNA localized to subcellular substructures S (NPM2, GMNN, H19, PCAF, DNMT3A, DNMT1, and STELLA), NS (SOX2, NANOG, POU5F1, and TET1), and FS (GCN) of MII oocyte. Immunoblotting revealed that specific maternal proteins DNMT3A and NANOG were asymmetrically enriched in MII-spindle-half of the oocytes. Topological analysis of sperm entry point (SEP) revealed that sperm preferentially entered via the MII-spindle-half of the oocytes. Even though, the topological position of first cleavage plane with regard to SEP was quite stochastic. Spatial comparison of lipid content revealed symmetrical distribution of lipids between 2-cell blastomeres. Lineage tracing using Dil, a fluorescent dye, revealed that while the progeny of leading blastomere of 2-cell embryos contributed to more cells in the developed blastocysts compared to lagging counterpart, the contributions of leading and lagging blastomeres to the embryonic-abembryonic parts of the developed blastocysts were almost unbiased. And finally, separated sister blastomeres of 2-cell embryos had an overall similar probability to arrest at any stage before the blastocyst (2-cell, 4-cell, 8-cell, and morula) or to achieve the blastocyst stage. It was concluded that the localization of maternal mRNAs and proteins at the spindle are evolutionarily conserved between mammals unfertilized ovine oocyte could be considered polar with

  20. Training the next generation of scientists: Modeling Infectious Disease and Water Quality of Montana Streams

    NASA Astrophysics Data System (ADS)

    Fytilis, N.; Wyman, S.; Lamb, R.; Stevens, L.; Kerans, B.; Rizzo, D. M.

    2010-12-01

    water quality and the presence of these taxa is important in determining stream health. In addition, system dynamics software (STELLA) is used to model the non-linear relationships and feedback between worm prevalence and disease dynamics. These types of collaborations between engineers, biologists, field ecologists and geneticists from secondary, post-secondary and higher institutions proved useful in linking complex geochemical data, worm community structure and molecular genetics to develop the next-generation scientists and better understand disease dynamics.

  1. A Comparison of Three Approaches to Model Human Behavior

    NASA Astrophysics Data System (ADS)

    Palmius, Joel; Persson-Slumpi, Thomas

    2010-11-01

    One way of studying social processes is through the use of simulations. The use of simulations for this purpose has been established as its own field, social simulations, and has been used for studying a variety of phenomena. A simulation of a social setting can serve as an aid for thinking about that social setting, and for experimenting with different parameters and studying the outcomes caused by them. When using the simulation as an aid for thinking and experimenting, the chosen simulation approach will implicitly steer the simulationist towards thinking in a certain fashion in order to fit the model. To study the implications of model choice on the understanding of a setting where human anticipation comes into play, a simulation scenario of a coffee room was constructed using three different simulation approaches: Cellular Automata, Systems Dynamics and Agent-based modeling. The practical implementations of the models were done in three different simulation packages: Stella for Systems Dynamic, CaFun for Cellular automata and SesAM for Agent-based modeling. The models were evaluated both using Randers' criteria for model evaluation, and through introspection where the authors reflected upon how their understanding of the scenario was steered through the model choice. Further the software used for implementing the simulation models was evaluated, and practical considerations for the choice of software package are listed. It is concluded that the models have very different strengths. The Agent-based modeling approach offers the most intuitive support for thinking about and modeling a social setting where the behavior of the individual is in focus. The Systems Dynamics model would be preferable in situations where populations and large groups would be studied as wholes, but where individual behavior is of less concern. The Cellular Automata models would be preferable where processes need to be studied from the basis of a small set of very simple rules. It is

  2. Diagnostic yield of the comprehensive assessment of developmental delay/mental retardation in an institute of child neuropsychiatry.

    PubMed

    Battaglia, A; Bianchini, E; Carey, J C

    1999-01-01

    The Consensus Conference of the American College of Medical Genetics has established guidelines regarding the evaluation of patients with mental retardation (MR) [Curry et al., Am. J. Med. Genet. 72:468-477, 1997]. They emphasized the high diagnostic utility of cytogenetic studies and of neuroimaging in certain clinical settings. However, data on the diagnostic yield of these studies in well-characterized populations of individuals with MR are scant. Majnemer and Shevell [J. Pediatr. 127:193-199, 1995] attained a diagnostic yield of 63%. However, this study included only 60 patients and the classification included pathogenetic and causal groups. The Stella Maris Institute has evaluated systematically patients with developmental delay (DD)/MR and performed various laboratory studies and neuroimaging in almost all patients. We report a retrospective analysis of the diagnostic yield of 120 consecutive patients observed at our Institute during the first 6 months of 1996. There were 77 males and 43 females; 47 were mildly delayed (IQ 70-50), 31 were moderately delayed (IQ 50-35), and 42 were severely delayed (IQ 35-20). Diagnostic studies (history, physical examination, standard cytogenetics, fragile X testing, molecular studies, electroencephalography, electromyography, nerve conduction studies, neuroimaging, and metabolic screening tests) yielded a causal diagnosis in 50 (41.6%) and a pathogenetic diagnosis in 47 (39.2%) of the 120 patients. Causal categories included chromosomal abnormalities (14), Fra(X) syndromes (4), known MCA/MR syndromes (19), fetal environmental syndromes (1), neurometabolic (3) disorders, neurocutaneous (3) disorders, hypoxic-ischemic encephalopathy (3), other encephalopathies (1), and congenital bilateral perisylvian syndrome (2). Pathogenetic categories included idiopathic MCA/MR syndromes (35), epileptic syndromes (10), and isolated lissencephaly sequence (2). Diagnostic yield did not differ across categories and degree of DD. Our results

  3. Chloride concentration affects Kv channel voltage-gating kinetics: Importance of experimental anion concentrations.

    PubMed

    Bekar, L K; Loewen, M E; Forsyth, G W; Walz, W

    2005-09-30

    Chloride concentration has been shown to have a dramatic impact on protein folding and subsequent tertiary conformation [K.D. Collins, Ions from the Hofmeister series and osmolytes: effects on proteins in solution and in the crystallization process, Methods 34 (2004) 300-311; I. Jelesarov, E. Durr, R.M. Thomas, H.R. Bosshard, Salt effects on hydrophobic interaction and charge screening in the folding of a negatively charged peptide to a coiled coil (leucine zipper), Biochemistry 37 (1998) 7539-7550]. As it is known that Kv channel gating is linked to the stability of the cytoplasmic T1 multimerization domain conformation [D.L. Minor, Y.F. Lin, B.C. Mobley, A. Avelar, Y.N. Jan, L.Y. Jan, J.M. Berger, The polar T1 interface is linked to conformational changes that open the voltage-gated potassium channel, Cell 102 (2000) 657-670; B.A. Yi, D.L. Minor Jr., Y.F. Lin, Y.N. Jan, L.Y. Jan, Controlling potassium channel activities: interplay between the membrane and intracellular factors, Proc. Natl. Acad. Sci. U.S.A. 98 (2001) 11016-11023] and that intracellular chloride concentration has been linked to Kv channel kinetics [L.K. Bekar, W. Walz, Intracellular chloride modulates A-type potassium currents in astrocytes, Glia 39 (2002) 207-216; W.B. Thoreson, S.L. Stella, Anion modulation of calcium current voltage dependence and amplitude in salamander rods, Biochim. Biophys. Acta 1464 (2000) 142-150], the objective of the present study was to address how chloride concentration changes affect Kv channel kinetics more closely in an isolated expression system. Initially, no significant chloride concentration-dependent effects on channel steady-state gating kinetics were observed. Only after disruption of the cytoskeleton with cytochalasin-D did we see significant chloride concentration-dependent shifts in gating kinetics. This suggests that the shift in gating kinetics is mediated through effects of intracellular chloride concentration on cytoplasmic domain tertiary

  4. Baseline characteristics and interim (3-month) efficacy and safety data from STELLA-LONG TERM, a long-term post-marketing surveillance study of ipragliflozin in Japanese patients with type 2 diabetes in real-world clinical practice.

    PubMed

    Maegawa, Hiroshi; Tobe, Kazuyuki; Tabuchi, Hiromi; Nakamura, Ichiro

    2016-10-01

    To evaluate the efficacy and safety of ipragliflozin in real-world clinical practice in Japanese patients with type 2 diabetes. We conducted interim analyses at 3 months of a 3-year prospective study of patients who were first prescribed ipragliflozin between 17 July 2014 and 16 October 2015, and whose data were locked by 16 January 2016. Changes in glycemic control, blood pressure, and laboratory variables from baseline, and incidence of adverse drug reactions (ADRs). Of 11,412 patients initially registered, efficacy and safety data were available for 3481 (30.5%) and 4360 (38.2%) patients, respectively. Hemoglobin A1c and fasting plasma glucose decreased by 0.67% and 28.8 mg/dL, respectively, at 3 months/last assessment (both P < .001) from baseline (8.00% and 166.4 mg/dL, respectively). Blood pressure and lipid levels also improved significantly. There were 258 ADRs in 194 patients. The ADRs included 'renal and urinary disorders' (system organ class) in 110 patients (2.5%). These 3-month interim results indicate that ipragliflozin improved glycemic control, lipids, and blood pressure with low rates of ADRs in Japanese patients with type 2 diabetes in real-world clinical practice. The results were consistent with those of placebo-controlled, randomized clinical trials. Clinicaltrials.gov identifier: NCT02479399.

  5. Transmission spectroscopy of the hot Jupiter TrES-3 b: Disproof of an overly large Rayleigh-like feature

    NASA Astrophysics Data System (ADS)

    Mackebrandt, F.; Mallonn, M.; Ohlert, J. M.; Granzer, T.; Lalitha, S.; García Muñoz, A.; Gibson, N. P.; Lee, J. W.; Sozzetti, A.; Turner, J. D.; Vaňko, M.; Strassmeier, K. G.

    2017-12-01

    Context. Transit events of extrasolar planets offer the opportunity to study the composition of their atmospheres. Previous work on transmission spectroscopy of the close-in gas giant (TrES)-3 b revealed an increase in absorption towards blue wavelengths of very large amplitude in terms of atmospheric pressure scale heights, too large to be explained by Rayleigh-scattering in the planetary atmosphere. Aims: We present a follow-up study of the optical transmission spectrum of the hot Jupiter TrES-3 b to investigate the strong increase in opacity towards short wavelengths found by a previous study. Furthermore, we aim to estimate the effect of stellar spots on the transmission spectrum. Methods: This work uses previously published long slit spectroscopy transit data of the Gran Telescopio Canarias (GTC) and published broad band observations as well as new observations in different bands from the near-UV to the near-IR, for a homogeneous transit light curve analysis. Additionally, a long-term photometric monitoring of the TrES-3 host star was performed. Results: Our newly analysed GTC spectroscopic transit observations show a slope of much lower amplitude than previous studies. We conclude from our results the previously reported increasing signal towards short wavelengths is not intrinsic to the TrES-3 system. Furthermore, the broad band spectrum favours a flat spectrum. Long-term photometric monitoring rules out a significant modification of the transmission spectrum by unocculted star spots. Based on (1) data obtained with the STELLA robotic telescopes in Tenerife, an AIP facility jointly operated by AIP and IAC, (2) observations collected at the German-Spanish Astronomical Center, Calar Alto, jointly operated by the Max-Planck-Institut für Astronomie Heidelberg and the Instituto de Astrofísica de Andalucía (CSIC) and (3) observations made with the Italian Telescopio Nazionale Galileo (TNG) operated on the island of La Palma by the Fundación Galileo Galilei of

  6. GJ 1214: Rotation period, starspots, and uncertainty on the optical slope of the transmission spectrum

    NASA Astrophysics Data System (ADS)

    Mallonn, M.; Herrero, E.; Juvan, I. G.; Essen, C. von; Rosich, A.; Ribas, I.; Granzer, T.; Alexoudi, X.; Strassmeier, K. G.

    2018-06-01

    to build the transmission spectrum. This degeneracy can only be broken by high-precision transit photometry resolving the spot crossing signature in the transit light curve. Based on data obtained with the STELLA robotic telescopes in Tenerife, an AIP facility jointly operated by AIP and IAC.The photometry tables are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/614/A35

  7. Revision of the Australian Union-Jack wolf spiders, genus Tasmanicosa (Araneae, Lycosidae, Lycosinae).

    PubMed

    Framenau, Volker W; Baehr, Barbara C

    2016-12-23

    The Australian wolf spider (Lycosidae Sundevall, 1833) genus Tasmanicosa Roewer, 1959 with Lycosa tasmanica Hogg, 1905 as type species is revised to include 14 species: T. godeffroyi (L. Koch, 1865), comb. nov. (= Lycosa tasmanica Hogg, 1905, syn. nov.; = Lycosa zualella Strand, 1907, syn. nov.; = Lycosa woodwardi Simon, 1909, syn. nov.); T. fulgor sp. nov.; T. gilberta (Hogg, 1905) comb. nov.; T. harmsi sp. nov.; T. hughjackmani sp. nov.; T. kochorum sp. nov.; T. leuckartii (Thorell, 1870), comb. nov. (= Lycosa molyneuxi Hogg, 1905, syn. nov.); T. musgravei (McKay, 1974) comb. nov.; T. phyllis (Hogg, 1905) comb. nov. (= Lycosa stirlingae Hogg, 1905, syn. nov.); T. ramosa (L. Koch, 1877), comb. nov.; T. salmo sp. nov.; T. semicincta (L. Koch, 1877) comb. nov.; T. stella sp. nov.; and T. subrufa (Karsch, 1878) comb. nov. Within the Australian wolf spider fauna, the genus Tasmanicosa can be diagnosed by the distinct pattern of radiating light and dark lines forming a "Union-Jack" pattern on the carapace. Male pedipalp morphology identifies the genus as part of the subfamily Lycosinae Sundevall, 1833 due to the presence of a transverse tegular apophysis with dorsal groove guiding the embolus during copulation. However, genital morphology is variable and a synapomorphy based on male pedipalp or female epigyne morphology could not be identified. Members of Tasmanicosa are comparatively large spiders (body length ca. 12-30 mm), that build a shallow burrow, which is sometimes covered with a flimsy trapdoor. Species of Tasmanicosa are largely a Bassian faunal element with preference for open woodlands and/or floodplains, although some species can be found into the semi-arid Australian interior. Two Australian wolf spider species may represent Tasmanicosa based on their original descriptions, but due to immature types in combination with the somatic similarities of all Tasmanicosa species, cannot be identified with certainty. They are therefore considered nomina dubia

  8. Development of a zoning-based environmental-ecological-coupled model for lakes to assess lake restoration effect

    NASA Astrophysics Data System (ADS)

    Xu, Mengjia; Zou, Changxin; Zhao, Yanwei

    2017-04-01

    Environmental/ecological models are widely used for lake management as they provide a means to understand physical, chemical and biological processes in highly complex ecosystems. Most research focused on the development of environmental (water quality) and ecological models, separately. Limited studies were developed to couple the two models, and in these limited coupled models, a lake was regarded as a whole for analysis (i.e., considering the lake to be one well-mixed box), which was appropriate for small-scale lakes and was not sufficient to capture spatial variations within middle-scale or large-scale lakes. This paper seeks to establish a zoning-based environmental-ecological-coupled model for a lake. The Baiyangdian Lake, the largest freshwater lake in Northern China, was adopted as the study case. The coupled lake models including a hydrodynamics and water quality model established by MIKE21 and a compartmental ecological model used STELLA software have been established for middle-sized Baiyangdian Lake to realize the simulation of spatial variations of ecological conditions. On the basis of the flow field distribution results generated by MIKE21 hydrodynamics model, four water area zones were used as an example for compartmental ecological model calibration and validation. The results revealed that the developed coupled lake models can reasonably reflected the changes of the key state variables although there remain some state variables that are not well represented by the model due to the low quality of field monitoring data. Monitoring sites in a compartment may not be representative of the water quality and ecological conditions in the entire compartment even though that is the intention of compartment-based model design. There was only one ecological observation from a single monitoring site for some periods. This single-measurement issue may cause large discrepancies particularly when sampled site is not representative of the whole compartment. The

  9. Use of System Thinking Software for Determining Climate Change Impacts in Water Balance for the Rio Yaqui Basin, Sonora, Mexico

    NASA Astrophysics Data System (ADS)

    Tapia, E. M.; Minjarez, J. I.; Espinoza, I. G.; Sosa, C. M.

    2013-05-01

    the most important basins in Sonora. It is located in northwestern Mexico, and covers an approximate area of 74,054 km2, providing water for one of the most prominent agricultural zones in the state. We used the System Thinking Software "Stella 9.0.2" to dynamically visualize the effects of climate change on the Rio Yaqui Basin. In this software, the main components of the water balance are simulated over the designated period of time with tools that include stocks and flow diagrams, causal loops, model equations and built in functions. Climate change projections for the Rio Yaqui Basin showed highly variable runoff behaviors, indicating the possibility of frequent droughts alternating with years of extraordinary runoff. Simulations generated through the System Thinking Software provides a reasonable basis for establishing policies for optimizing storage of water during extraordinary runoff periods that can serve as water supplies during frequent droughts.

  10. The 8th International Conference on Highly Frustrated Magnetism (HFM 2016)

    NASA Astrophysics Data System (ADS)

    Gardner, J. S.; Kao, Y. J.

    2017-04-01

    decided at the conference that the next HFM conference will be held in two years, in 2018, on the campus of UC Davis, followed one in Shanghai around December 2019. Finally, on behalf of the HFM 2016 Organizing Committee, I wish to deeply thank all the people who generously helped us in organizing and running the HFM 2016 conference. These include the numerous funding sources, Committee Members, Program and Session chairs, Chia-Chi Liu, Chao-Jung Kuo, Hanz Peng, Laura Bravo and Stella Su and of course all the participants, without you it would have simply been another wet week in Taipei. One might remember HFM2016 for the power outage, but we hope you remember the taste, sounds and views of Taipei as well as stimulation conversations and hopefully the beginnings of productive partnerships.

  11. Transmission spectroscopy of the inflated exo-Saturn HAT-P-19b

    NASA Astrophysics Data System (ADS)

    Mallonn, M.; von Essen, C.; Weingrill, J.; Strassmeier, K. G.; Ribas, I.; Carroll, T. A.; Herrero, E.; Granzer, T.; Claret, A.; Schwope, A.

    2015-08-01

    estimate of 5.5+ 1.8-1.3 Gyr by gyrochronology. The calculated correction of the transit depth for unocculted spots on the visible hemisphere was found to be well within the derived 1σ uncertainty of the white-light curve and the spectral data points of the transmission spectrum. Based on observations made with the Gran Telescopio Canarias (GTC), installed in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias, in the island of La Palma, as well as on data obtained with the STELLA robotic telescope in Tenerife, an AIP facility jointly operated by AIP and IAC.Tables 1 and 3 are available in electronic form at http://www.aanda.org

  12. Modeling High Rate Phosphorus and Nitrogen Removal in a Vertical Flow Alum Sludge based Constructed Wetlands

    NASA Astrophysics Data System (ADS)

    Jeyakumar, Lordwin; Zhao, Yaqian

    2014-05-01

    Increased awareness of the impacts of diffuse pollution and their intensification has pushed forward the need for the development of low-cost wastewater treatment techniques. One of such efforts is the use of novel DASC (Dewatered Alum Sludge Cakes) based constructed wetlands (CWs) for removing nutrients, organics, trace elements and other pollutants from wastewater. Understanding of the processes in CWs requires a numerical model that describes the biochemical transformation and degradation processes in subsurface vertical flow (VF) CWs. Therefore, this research focuses on the development of a process-based model for phosphorus (P) and nitrogen (N) removal to achieve a stable performance by using DASC as a substrate in CWs treatment system. An object-oriented modelling tool known as "STELLA" which works based on the principle of system dynamics is used for the development of P and N model. The core objective of the modelling work is oriented towards understanding the process in DASC-based CWs and optimizes design criteria. The P and N dynamic model is developed for DASC-based CWs. The P model developed exclusively for DASC-based CW was able to simulate the effluent P concentration leaving the system satisfactorily. Moreover, the developed P dynamic model has identified the major P pathways as adsorption (72%) followed by plant uptake (20%) and microbial uptake (7%) in single-stage laboratory scale DASC-based CW. Similarly, P dynamic simulation model was developed to simulate the four-stage laboratory scale DASC-based CWs. It was found that simulated and observed values of P removal were in good agreement. The fate of P in all the four stages clearly shows that adsorption played a pivotal role in each stage of the system due to the use of the DASC as a substrate. P adsorption by wetland substrate/DASC represents 59-75% of total P reduction. Subsequently, plant uptake and microbial uptake have lesser role regarding P removal (as compared to adsorption).With regard

  13. Pediatric acute lymphoblastic leukemia.

    PubMed

    Carroll, William L; Bhojwani, Deepa; Min, Dong-Joon; Raetz, Elizabeth; Relling, Mary; Davies, Stella; Downing, James R; Willman, Cheryl L; Reed, John C

    2003-01-01

    The outcome for children with acute lymphoblastic leukemia (ALL) has improved dramatically with current therapy resulting in an event free survival exceeding 75% for most patients. However significant challenges remain including developing better methods to predict which patients can be cured with less toxic treatment and which ones will benefit from augmented therapy. In addition, 25% of patients fail therapy and novel treatments that are focused on undermining specifically the leukemic process are needed urgently. In Section I, Dr. Carroll reviews current approaches to risk classification and proposes a system that incorporates well-established clinical parameters, genetic lesions of the blast as well as early response parameters. He then provides an overview of emerging technologies in genomics and proteomics and how they might lead to more rational, biologically based classification systems. In Section II, Drs. Mary Relling and Stella Davies describe emerging findings that relate to host features that influence outcome, the role of inherited germline variation. They highlight technical breakthroughs in assessing germline differences among patients. Polymorphisms of drug metabolizing genes have been shown to influence toxicity and the best example is the gene thiopurine methyltransferase (TPMT) a key enzyme in the metabolism of 6-mercaptopurine. Polymorphisms are associated with decreased activity that is also associated with increased toxicity. The role of polymorphisms in other genes whose products play an important role in drug metabolism as well as cytokine genes are discussed. In Sections III and IV, Drs. James Downing and Cheryl Willman review their findings using gene expression profiling to classify ALL. Both authors outline challenges in applying this methodology to analysis of clinical samples. Dr. Willman describes her laboratory's examination of infant leukemia and precursor B-ALL where unsupervised approaches have led to the identification of

  14. Integrating scientific argumentation to improve undergraduate writing and learning in a global environmental change course

    NASA Astrophysics Data System (ADS)

    Kreutz, K. J.; Koffman, B. G.; Trenbath, K. L.

    2013-12-01

    What makes a good scientific argument? We began ERS201: Global Environmental Change by asking students to reflect on the mechanics of a strong scientific argument. At the same time, we asked them to evaluate global CO2 and sea level data from different time periods in Earth's history to answer the question, 'Is there a relationship between atmospheric CO2 and sea level, and if so, why?' This question formed the theme for the course, a mid-level, inquiry-based class of about 20 students. Each week, students target specific aspects of the climate system through problem sets, which include experimental and laboratory work, basic statistical analyses of paleoclimate datasets, and the development of simple systems models using STELLA software. Every 2-4 weeks, we challenge students to write short (1500 word) data-driven scientific arguments, which require a synthesis of information from their problem sets and from the scientific literature. Students have to develop a clear, testable hypothesis related to each writing prompt, and then make their case using figures they have generated during the weekly problem sets. We evaluate student writing using a rubric that focuses on the structure and clarity of the argument, relevance of the data included, and integration and quality of the graphics, with a lesser emphasis placed on voice and style. In 2013, student scores improved from a median value of 86 × 9% to 94 × 8% over the course of the semester. More importantly, we found that incorporation of scientific argumentation served to increase student understanding of important and sometimes abstract scientific concepts. For example, on pre- and post-course assessments we asked the question, 'What would happen if a significant portion of the sea ice floating in the Arctic Ocean were to melt?' On the pre-assessment, 80% of students said that it would lead to more coastal flooding, while only 20% correctly stated that a decrease in the reflection of solar energy would lead to

  15. Mineral Soil Carbon in Managed Hardwood Forests of the Northeastern US

    NASA Astrophysics Data System (ADS)

    Vario, C.; Friedland, A.; Hornig, C.

    2013-12-01

    New England is characterized by extensive forest cover and large reservoirs of soil carbon (C). In northern hardwood forests, mineral soil C can account for up to 50% of total ecosystem C. There has been an increasing demand for forests to serve both as a C sink and a renewable energy source, and effective management of the ecosystem C balance relies on accurate modeling of each compartment of the ecosystem. However, the dynamics of soil C storage with respect to forest use are variable and poorly understood, particularly in mineral soils. For example, current regional models assume C pools after forest harvesting do not change, while some studies suggest that belowground mineral soil C pools can be affected by disturbances at the soil surface. We quantified mineral soil C pools in previously clear-cut stands in seven research or protected forests across New York, New Hampshire, Massachusetts, and Vermont. The ages of the sites sampled ranged from recently cleared to those with no disturbance history, with 21 forest stands represented in the study. Within each research forest studied, physical parameters such as soil type, forest type, slope and land-use history (aside from forest harvest) did not vary between the stands of different ages. Soil samples were collected to a depth of 60 cm below the mineral-organic boundary using a gas-powered augur and 9.5-cm diameter drill bit. Samples were collected in 10-cm increments in shallow mineral soil and 15-cm increments from 30-60 cm depth. Carbon, nitrogen (N), pH, texture and soil mineralogy were measured across the regional sites. At Bartlett Experimental Forest (BEF) in New Hampshire, mineral soil biogeochemistry in cut and uncut sites was studied at a finer scale. Measurements included soil temperature to 55 cm depth, carbon compound analyses using Py-GCMS and soil microbial messenger RNA extractions from mineral soil. Finally, we simulated C dynamics after harvesting by building a model in Stella, with a particular

  16. Experimental and field investigations on uprooting of riparian vegetation

    NASA Astrophysics Data System (ADS)

    Calvani, Giulio; Francalanci, Simona; Solari, Luca; Gumiero, Bruna

    2017-04-01

    balance between drag and resisting forces acting on the single plant. In order to compare experimental results with real river conditions, we also performed field measurements of Salix Purpurea resistance to uprooting on a lateral bar in the Ombrone Pistoiese river. Ongoing research is focused on i) the definition of threshold criteria for the prediction of vegetation uprooting, ii) interpretation, by means of numerical modelling, of vegetation removal on a lateral bar in the Ombrone Pistoiese river during a flood that occurred on 19th November 2016. References Bywater-Reyes, Sharon, Andrew C Wilcox, John C Stella, and Anne F Lightbody. 2015. 'Flow and Scour Constraints on Uprooting of Pioneer Woody Seedlings'. Water Resources Research 51 (11): 9190-9206. Corenblit, Dov, Eric Tabacchi, Johannes Steiger, and Angela M Gurnell. 2007. 'Reciprocal Interactions and Adjustments between Fluvial Landforms and Vegetation Dynamics in River Corridors: A Review of Complementary Approaches'. Earth-¬-Science Reviews 84(1): 56-86. Edmaier, K, P Burlando, and P Perona. 2011. 'Mechanisms of Vegetation Uprooting by Flow in Alluvial Non- Cohesive Sediment'. Hydrology and Earth System Sciences 15(5): 1615-1627.

  17. Gypsum karst in Italy: a review

    NASA Astrophysics Data System (ADS)

    De Waele, Jo; Chiarini, Veronica; Columbu, Andrea; D'Angeli, Ilenia M.; Madonia, Giuliana; Parise, Mario; Piccini, Leonardo; Vattano, Marco; Vigna, Bartolomeo; Zini, Luca; Forti, Paolo

    2016-04-01

    . Forti P., Lucci P. (Eds.) (2010) - Il Progetto Stella-Basino. Studio multidisciplinare di un sistema carsico nella Vena del Gesso Romagnola. Memorie Ist. It. Spel. II(14), 260 p. Lucci P., Piastra S. (Eds.) (2015), I Gessi di Brisighella e Rontana: studio multidisciplinare di un'area carsica nella Vena del Gesso Romagnola. Memorie Ist. It. Spel. II(28), 751 p. Madonia G., Forti P. (2003) - Le aree carsiche gessose d'Italia. Memorie Ist. It. Spel. II(14), 285 p. Madonia G., Vattano M. (2011) - New knowledge on the Monte Conca gypsum karst system (central-western Sicily, Italy). Acta Carsologica, 40, (1), pp. 53-64. Marinelli O. (1917) - Fenomeni carsici nelle regioni gessose d'Italia. Mem. Geografiche di Giotto Dainelli, 34, pp. 263-416, suppl. to Riv. Geografica It Tedeschi L. et al. (2015) - Comportamento idrogeologico di alcune risorgenti carsiche nei gessi dell'Emilia-Romagna. Memorie Ist. It. Spel. II(29), pp. 399-404. Vigna B. et al. (2010) - Evolution of karst in Messinian gypsum (Monferrato, Northern Italy). Geodinamica Acta, 23(1-3), pp. 29-40. Zini L. et al. (2015) - a multidisciplinary approach in sinkhole analysis: the Quinis village case study (NE-Italy). Engineering Geology, 197, pp.132-144.

  18. Age and speleogenesis of epigenic gypsum caves in the northern Apennines (Italy)

    NASA Astrophysics Data System (ADS)

    Columbu, Andrea; Chiarini, Veronica; De Waele, Jo; Drysdale, Russell; Forti, Paolo; Hellstrom, John; Woodhead, Jon

    2016-04-01

    Triassic and Messinian gypsum beds host the majority of the caves in the eastern flank of the northern Apennines. To date, more than six hundreds voids have been mapped, including the longest known epigenic gypsum cave system in the world (Spipola-Acquafredda, ~11 km of tunnels) (De Waele et al., 2013). Superimposed caves are typically sub-horizontal (Klimchouk, 2000) and connected through vertical shafts, reflecting the palaeo base-level variations. When preserved, river terraces at the surface lie at the same palaeo altitude of the base level and horizontal cave passages. Notwithstanding the well-known geology of the area known (Vai and Martini, 2001), the age of these caves has been greatly underestimated in the past. Considering the rapid dissolution of the gypsum and uplifting of the area, the start of speleogenesis activity was considered to have occurred during the last glacial age. The age of karst voids can be only indirectly estimated by the dating of the infilling sediments. U-Th dating on carbonate speleothems provides high-precision and accurate ages (Hellstrom, 2003; Scholz and Hoffmann, 2008). We thus applied this methodology to 20 speleothems coming from 14 different caves belonging to the Monte Tondo, Spipola Acquafredda, Castelnuovo, Stella-Rio Basino and Brisighella systems. The results show that: i) caves were forming since at least ~300 ka; ii) the peak of speleogenesis was reached during relatively cold climate stages, when rivers formed terraces at the surface and aggradation caused paragenesis in the stable cave levels (Columbu et al., 2015). Besides the significant contribution to the understanding of the Apennines evaporite karst evolution, this study (and its further advancement) may also refine knowledge of the local vs regional uplifting rates and base-level variations since the late Pleistocene (Wegmann and Pazzaglia, 2009). References Columbu, A., De Waele, J., Forti, P., Montagna, P., Picotti, V., Pons-Branchu, E., Hellstrom, J

  19. Constraining fault activity by investigating tectonically-deformed Quaternary palaeoshorelines using a synchronous correlation method: the Capo D'Orlando Fault as a case study (NE Sicily, Italy)

    NASA Astrophysics Data System (ADS)

    Meschis, Marco; Roberts, Gerald P.; Robertson, Jennifer

    2016-04-01

    each palaeoshoreline from the initial work by Giunta et al., (2011) using synchronous correlation. This alternative approach suggests that uplift rates were constant through the Late Quaternary, suggesting that the fault slip-rate governing seismic hazard has also been constant. Reference Armijo, R., Meyer, B. G. C. P., King, G. C. P., Rigo, A., & Papanastassiou, D. (1996). Quaternary evolution of the Corinth Rift and its implications for the Late Cenozoic evolution of the Aegean. Geophysical Journal International, 126(1): 11 - 53. Basili R., Valensise, G., Vannoli, P., Burrato, P., Fracassi, U., Mariano, S., Tiberti, M.M., Boschi. E. (2008). The Database of Individual Seismogenic Sources (DISS), version 3: summarizing 20 years of research on Italy's earthquake geology, Tectonophysics, doi:10.1016/j.tecto.2007.04.014. Giunta, G., Gueli, A.M., Monaco, C., Orioli, S., Ristuccia, G.M., Stella, G., Troja, S.O. (2011). Middle-Late Pleistocene marine terraces and fault activity in the Sant'Agata di Militello coastal area (north-eastern Sicily). Journal of Geodynamics. 55, 32 - 40. Roberts, G. P., Meschis, M., Houghton, S., Underwood, C., & Briant, R. M. (2013). The implications of revised Quaternary palaeoshoreline chronologies for the rates of active extension and uplift in the upper plate of subduction zones.Quaternary Science Reviews, 78: 169 - 187.

  20. Advancements in near real time mapping of earthquake and rainfall induced landslides in the Avcilar Peninsula, Marmara Region

    NASA Astrophysics Data System (ADS)

    Coccia, Stella

    2014-05-01

    Stella COCCIA (1), Fiona THEOLEYRE (1), Pascal BIGARRE(1) , Semih ERGINTAV(2), Oguz OZEL(3) and Serdar ÖZALAYBEY(4) (1) National Institute of Industrial Environment and Risks (INERIS) Nancy, France, (2) Kandilli Observatory and Earthquake Research Institute (KOERI), Istanbul, Turkey, (3) Istanbul University (IU), Istanbul, Turkey, (4) TUBITAK MAM, Istanbul, Turkey The European Project MARsite (http://marsite.eu/), started in 2012 and leaded by the KOERI, aims to improve seismic risk evaluation and preparedness to face the next dreadful large event expected for the next three decades. MARsite is thus expected to move a "step forward" the most advanced monitoring technologies, and offering promising open databases to the worldwide scientific community in the frame of other European environmental large-scale infrastructures, such as EPOS (http://www.epos-eu.org/ ). Among the 11 work packages (WP), the main aim of the WP6 is to study seismically-induced landslide hazard, by using and improving observing and monitoring systems in geological, hydrogeotechnical and seismic onshore and offshore areas. One of the WP6 specific study area is the Avcilar Peninsula, situated between Kucukcekmece and Buyukcekmece Lakes in the north-west of the region of Marmara. There, more than 400 landslides are located. According to geological and geotechnical investigations and studies, soil movements of this area are related to underground water and pore pressure changes, seismic forces arising after earthquakes and decreasing sliding strength in fissured and heavily consolidated clays. The WP6 includes various tasks and one of these works on a methodology to develop a dynamic system to create combined earthquake and rainfall induced landslides hazard maps at near real time and automatically. This innovative system could be used to improve the prevention strategy as well as in disaster management and relief operations. Base on literature review a dynamic GIS platform is used to combine

  1. Accretion-powered Compact Binaries

    NASA Astrophysics Data System (ADS)

    Mauche, Christopher W.

    2003-12-01

    Preface; The workshop logo; A short history of the CV workshop F. A. Córdova; Part I. Observations: 1. Low mass x-ray binaries A. P. Cowley, P. C. Schmidtke, D. Crampton, J. B. Hutchings, C. A. Haswell, E. L. Robinson, K. D. Horne, H. M. Johnston, S. R. Kulkarni, S. Kitamoto, X. Han, R. M. Hjellming, R. M. Wagner, S. L. Morris, P. Hertz, A. N. Parmar, L. Stella, P. Giommi, P. J. Callanan, T. Naylor, P. A. Charles, C. D. Bailyn, J. N. Imamura, T. Steiman-Cameron, J. Kristian, J. Middleditch, L. Angelini and J. P. Noris; 2. Nonmagnetic cataclysmic variables R. S. Polidan, C. W. Mauche, R. A. Wade, R. H. Kaitchuck, E. M. Schlegel, P. A. Hantzios, R. C. Smith, J. H. Wood, F. Hessman, A. Fiedler, D. H. P. Jones, J. Casares, P. A. Charles, J. van Paradijs, E. Harlaftis, T. Naylor, G. Sonneborn, B. J. M. Hassall, K. Horne, C. A. la Dous, A. W. Shafter, N. A. Hawkins, D. A. H. Buckley, D. J. Sullivan, F. V. Hessman, V. S. Dhillon, T. R. Marsh, J. Singh, S. Seetha, F. Giovannelli, A. Bianchini, E. M. Sion, D. J. Mullan, H. L. Shipman, G. Machin, P. J. Callanan, S. B. Howell, P. Szkody, E. M. Schlegel and R. F. Webbink; 3. Magnetic cataclysmic variables C. Hellier, K. O. Mason, C. W. Mauche, G. S. Miller, J. C. Raymond, F. K. Lamb, J. Patterson, A. J. Norton, M. G. Watson, A. R. King, I. M. McHardy, H. Lehto, J. P. Osborne, E. L. Robinson, A. W. Shafter, S. Balachandran, S. R. Rosen, J. Krautter, W. Buchholz, D. A. H. Buckley, I. R. Tuoly, D. Crampton, B. Warner, R. M. Prestage, B. N. Ashoka, M. Mouchet, J. M. Bonnet-Bidaud, J. M. Hameury, P. Szkody, P. Garnavich, S. Howell, T. Kii, M. Cropper, K. Mason, J. Bailey, D. T. Wickramasinghe, L. Ferrario, K. Beuermann, A. D. Schwope, H.-C. Thomas, S. Jordan, J. Schachter, A. V. Filippenko, S. M. Kahn, F. B. S. Paerels, K. Mukai, M. L. Edgar, S. Larsson, R. F. Jameson, A. R. King, A. Silber, R. Remillard, H. Bradt, M. Ishida, T. Ohashi and G. D. Schmidt; Part II. Accretion Theory: 4. Nonmagnetic W. Kley, F. Geyer, H. Herold, H

  2. Thermospheric density and satellite drag modeling

    NASA Astrophysics Data System (ADS)

    Mehta, Piyush Mukesh

    GRACE satellites. Moving toward accurate atmospheric models and absolute densities requires physics based models for CD. Closed-form solutions of CD have been developed and exist for a handful of simple geometries (flat plate, sphere, and cylinder). However, for complex geometries, the Direct Simulation Monte Carlo (DSMC) method is an important tool for developing CD models. DSMC is computationally intensive and real-time simulations for CD are not feasible. Therefore, parameterized models for CD are required. Modeling CD for an RSO requires knowledge of the gas-surface interaction (GSI) that defines the manner in which the atmospheric particles exchange momentum and energy with the surface. The momentum and energy exchange is further influenced by likely adsorption of atomic oxygen that may partially or completely cover the surface. An important parameter that characterizes the GSI is the energy accommodation coefficient, α. An innovative and state-of-the-art technique of developing parameterized drag coefficient models is presented and validated using the GRACE satellite. The effect of gas-surface interactions on physical drag coefficients is examined. An attempt to reveal the nature of gas-surface interactions at altitudes above 500 km is made using the STELLA satellite. A model that can accurately estimate CD has the potential to: (i) reduce the sources of uncertainty in the drag model, (ii) improve density estimates by resolving time-varying biases and moving toward absolute densities, and (iii) increase data sources for density estimation by allowing for the use of a wide range of RSOs as information sources. Results from this work have the potential to significantly improve the accuracy of conjunction analysis and SSA.

  3. Bringing Water into an Integrated Assessment Framework

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

    Izaurralde, Roberto C.; Thomson, Allison M.; Sands, Ronald

    streamflow through The Dalles dam. Water also enters the Columbia River via runoff from land. The model runs on a monthly timescale to account for the impact of seasonal variations of climate, streamflows, and water uses. Data for the model prototype were obtained from national databases and ecosystem model results. The WPM can be run from three sources: 1) directly from STELLA, 2) with the isee Player®, or 3) the web version of WPM constructed with NetSim® software. When running any of these three versions, the user is presented a screen with a series of buttons, graphs, and a table. Two of the buttons provide the user with background and instructions on how to run the model. Currently, there are five types of scenarios that can be manipulated alone or in combination using the Sliding Input Devices: 1) interannual variability (e.g., El Niño), 2) climate change, 3) salmon policy, 4) future population, and 5) biodiesel production. Overall, the WPM captured the effects of streamflow conditions on hydropower production. Under La Niña conditions, more hydropower is available during all months of the year, with a substantially higher availability during spring and summer. Under El Niño conditions, hydropower would be reduced, with a total decline of 15% from normal weather conditions over the year. A policy of flow augmentation to facilitate the spring migration of smolts to the ocean would also reduce hydropower supply. Modeled hydropower generation was 23% greater than the 81 TWh reported in the 1995 U.S. Geological Survey (USGS) database. The modeling capability presented here contains the essential features to conduct basin-scale analyses of water allocation under current and future climates. Due to its underlying data structure iv and conceptual foundation, the WPM should be appropriate to conduct IA modeling at national and global scales.« less

  4. 3D modelling of the Austroalpine-Penninic collisional wedge of the NW Alps: dataset management and preliminary results

    NASA Astrophysics Data System (ADS)

    Monopoli, Bruno; Bistacchi, Andrea; Bertolo, Davide; Dal Piaz, Giovanni; Gouffon, Yves; Massironi, Matteo; Sartori, Mario; Vittorio Dal Piaz, Giorgio

    2016-04-01

    considered as a sort of pseudo-stratigraphy, since they are the oldest feature that can be traced continuously at the map scale. For this reason we have developed a set of attributes identifying the tectonic and lithological units (a "legend"), implemented both in the GIS database and in the 3D models, which at the same time is compatible with the data structure of 3D modelling packages like Move and Skua/Gocad, and allows tracing the complex hierarchic classification of the units mapped in the GIS. This allows for the almost automatic and consistent two-way transfer of data between the GIS and geomodelling environments. E.g. results of 3D modelling, which is based on input data originally stored in the GIS, will eventually be transferred back to the GIS. The results of this study, which are preliminarily presented here, will open new opportunities to study the collision- and subduction-related nappe architecture and kinematics with younger deformations removed, and will eventually lead (with additional studies) to a step-by-step retrodeformation supported by modern technologies, following the path traced by Argand at the beginning of the 20th century. Argand E. 1909. L'exploration géologique des Alpes pennines centrales. Bull. Soc. Vaudoise Sci. Nat., 45, 217-276. Argand A. 1911. Les nappes de recouvrement des Alpes pennines et leurs prolongements structuraux. Mat. Carte Géol. Suisse, 31, 25. Argand A. 1916. Sur l'arc des Alpes occidentales. Eclogae Geol. Helv., 14, 145-191. Franchi S., Mattirolo E., Novarese V., Stella A. & Zaccagna D. 1908. Carta geologica delle Alpi Occidentali alla scala 1:400.000. Regio Ufficio Geologico, Roma. Gerlach H. 1869. Die Penninischen Alpen. N. Denkschr. Schweiz. Natf. Ges., 23, 132. Gerlach H. 1871. Das Suedwestliche Wallis. Beitraege Geol. Karte Schweiz, 9, 175. Giordano F. 1869. Sulla orografia e sulla geologica costituzione del Gran Cervino. Atti R. Acc. Sci. Torino, 4, 304-321.

  5. TYCHO Brahe's Empiric Methods, His Instruments, His Sudden Escape from Denmark and a New Theory About His Death

    NASA Astrophysics Data System (ADS)

    Thykier, C.

    1992-07-01

    Tycho Brahe (1546-1601) was born a noble being, a son of Otto Brahe, and a member of the Royal Danish Council. Very early he developed a great interest in science and especially astronomy. In 1575 Tycho visited the learned Prince Wilhelm II in Kassel. Here he was inspired by the famous instrument maker Burgi to build new precise astronomical instruments, and on the recommendation of Wilhelm King Frederic II of Denmark was given the island Hven (which at that time belonged to Denmark) as an entailed estate. At 26 years old, Tycho became famous for his work DE NOVA STELLA on the supernova that brightened up in 1572, and since this phenomenon kept its position fixed among the stars, it immediately invalidated the Aristotelian dogma of the invariability of the fixed-star world. In 1577 Tycho observed the great comet and followed its celestial motion by means of a quadrant and a sextant. He then came to the conclusion that the comet orbit moved far out among the planets, in contradiction to the Aristotelian dogma of the crystal spheres for the planets. However, Tycho's great contribution to science was his construction of the observatory buildings Uraniborg and Stjerneborg ("Star Castle") with their equipment of ancient sighting instruments and his use of these instruments without telescopes for observations of the planets over a period of almost 20 years. Tycho's work is collected in 15 volumes, OPERA OMNIA by J. L. E. Dreyer. Tycho also mapped Hven correctly and he triangulated both sides of Oresund relative to Hven. When Tycho moved to Prague in 1599 he lived there for a couple of years and met Kepler who became his assistant and collaborator. Kepler was the one who analyzed Tycho's material and derived the Keplerian laws for the motions of the planets. On this basis Newton derived the law of gravitation. Tycho Brahe has been considered the father of modern empirical science. In 1596 he was accused of negligence of his administrative duties and several other things

  6. Ecosystem's Modeling of Bhoj Wetland - A Base For Economic Valuation and Sustainable Management

    NASA Astrophysics Data System (ADS)

    Verma, M.; Bakshi, N.; Nair, R.

    terms of productivity losses and health impacts? How feedback can be taken from these impacts to revise or develop management policies and to seek participation of stakeholders to check wet- land degradation or losses? What type of benefits accrues to people from this wetland? What is the willingness of the people to pay to conserve this important water body? Lake degradation is due to multiple causes hence lakeSs restoration requires multi- ple interventions. To suggest such interventions and above all their prioritizations, an 1 ecosystem model for the lake has been developed following the systemSs dynamics approach. The main objective of the Ecosystem Modeling of the wetland was to under- stand the changes in the hydrology of the wetland first on account of certain changes in the conditions of the surroundings such that valuation process can be followed with current and future scenarios of the lakes hydrology in hand. A sophisticated computer software called as STELLA was used for the modeling exercise. The model used wa- ter quality parameters to show the impact of flow of sewage on dissolved oxygen, bio-chemical oxygen demand, pH, total hardness, total alkalinity, bacterial count and growth of weeds. A base scenario has been created and various simulation runs have been performed for the pre and ongoing restoration activities for next 25 years so as to represent the health of the wetlandSs ecosystem. These scenarios have then been used in the valuation exercise to estimate the conservation value of the lake. Various valuation techniques like contingent valuation, production function approach, hedonic pricing and supply cost have been used to capture the economic values as perceived by different stakeholders. These scenarios and the valuation exercises further throw light on the prioritization of future policy intervention for sustainable management of this urban wetland. Key words: Ecosystem Services, Water Quality Parameters, EcosystemSs Modeling, Economic

  7. [Community organizations and fighting STDs, HIV and AIDS in Montreal: lessons for sub-Saharan Africa].

    PubMed

    Agonnoude, Maurice T; Mesenge, C

    2010-01-01

    discourse on AIDS legible to broader populations, for the borderlines between these target groups and the rest of the population is very fuzzy. Discussion and lessons: This analysis of the process of fighting HIV/AIDS inMontreal identified some positive experiences that can inspire concrete actions in African setting. One is the experience of the Farha Foundation, an organisation specialized in community fund-raising, which puts its collections at the disposal of other community organisations, and is independent, receiving no funding from local, provincial or federal public authorities. Transposition of this experience to Africa would require contextualisation and would need to mobilize the resources of not only the local community but also the national and international communities. The "Ruban en route" organization provides useful awareness programs for the young, visiting primary and secondary schools to debate HIV/AIDS issues with students with games, and demonstrating condom use. In the African context, given the limited educational system and the extent of school quitting, such an organisation would need to find a means to reach young apprentices and young farmers in informal structures. Action Séro Zero and Stella target male homosexuals and sex workers, respectively, and work to have their rights recognized by the community. The application of their policies would not be possible in our societies, for sociocultural reasons. Instead efforts must be directed toward making the community understand the need to encourage and tolerate recognition and aid for prostitutes, for the good of all. To a lesser degree, the experience of "Spectre de rue" with the TAPAJ project (Travail Alternatif Payé A la Journée or alternative work paid daily) is also importable, although only in urban environments where "street kids" are an important phenomenon. In some cities, where their number is increasing, this activity can be connected to an organisation working on awareness campaigns

  8. Cannibal Stars Cause Giant Explosions in Fornax Cluster Galaxy

    NASA Astrophysics Data System (ADS)

    2000-07-01

    The VLT Observes Most Remote Novae Ever Seen About 70 million years ago, when dinosaurs were still walking on the Earth, a series of violent thermo-nuclear explosions took place in a distant galaxy. After a very long travel across vast reaches of virtually empty space (70 million light-years, or ~ 7 x 10 20 km), dim light carrying the message about these events has finally reached us. It was recorded by the ESO Very Large Telescope (VLT) at the Paranal Observatory (Chile) during an observing programme by a group of Italian astronomers [1]. The subsequent analysis has shown that the observers witnessed the most distant nova outbursts ever seen . They were caused by "stellar cannibalism" in binary systems in which one relatively cool star loses matter to its smaller and hotter companion. An instability results that leads to the ignition of a "hydrogen bomb" on the surface of the receiving star. The "Stella Nova" Phenomenon A stellar outburst of the type now observed with the VLT is referred to as a "Stella Nova" ("new star" in Latin), or just "Nova" . Novae caused by explosions in binary stars in our home galaxy, the Milky Way system, are relatively frequent and about every second or third year one of them is bright enough to be easily visible with the naked eye. For our ancestors, who had no means to see the faint binary star before the explosion, it looked as if a new star had been born in the sky, hence the name. The most common nova explosion occurs in a binary stellar system in which a white dwarf (a very dense and hot, compact star with a mass comparable to that of the Sun and a size like the Earth) accretes hydrogen from a cooler and larger red dwarf star [2]. As the hydrogen collects on the surface of the white dwarf star, it becomes progressively hotter until a thermonuclear explosion is ignited at the bottom of the collected gas. A huge amount of energy is released and causes a million-fold increase in the brightness of the binary system within a few hours

  9. Deep Sky Diving with the ESO New Technology Telescope

    NASA Astrophysics Data System (ADS)

    1998-01-01

    Padova, Italy), Luiz da Costa (ESO), Eiichi Egami (MPI Extraterrestrial Physics, Garching, Germany), Adriano Fontana (Rome Observatory, Italy), Bernard Fort (Paris Observatory, France), Laurent Gautret (Paris Observatory, France), Emanuele Giallongo (Rome Observatory, Italy), Roberto Gilmozzi, Richard N.Hook and Bruno Leibundgut (ESO), Yannick Mellier and Patrick Petitjean (IAP, Paris, France), Alvio Renzini, Sandra Savaglio and Peter Shaver (ESO), Stella Seitz (Munich Observatory, Germany) and Lin Yan (ESO). [2]. The photometric redshift method allows to determine an approximate distance of a distant galaxy by measuring its colour, i.e., its relative brightness (magnitude) in different wavebands. It is based on the proportionality between the distance of a galaxy and its recession velocity (the Hubble law). The higher the velocity, the more its emission will be shifted towards longer wavelengths and the redder is the colour. Recent investigations of galaxies seen in the Hubble Deep Field have shown that the redshifts (and thus distances) found by this method are quite accurate in most cases. How to obtain ESO Press Information ESO Press Information is made available on the World-Wide Web (URL: http://www.eso.org ). ESO Press Photos may be reproduced, if credit is given to the European Southern Observatory.

  10. The Dark Side of Nature: the Crime was Almost Perfect

    NASA Astrophysics Data System (ADS)

    2006-12-01

    Astrofisico di Arcetri, Italy), Guido Chincarini (INAF, Osservatorio Astronomico di Brera & Università degli Studi di Milano-Bicocca, Italy), Nino Panagia (Space Telescope Science Institute, USA), Gianpiero Tagliaferri, Dino Fugazza, Sergio Campana, Stefano Covino, and Paolo D'Avanzo (INAF, Osservatorio Astronomico di Brera, Italy), Daniele Malesani (SISSA/ISAS, Italy and Dark Cosmology Centre, Copenhagen), Vincenzo Testa, L. Angelo Antonelli, Silvia Piranomonte, and Luigi Stella (INAF, Osservatorio Astronomico di Roma, Italy), Vanessa Mangano (INAF/IASF Palermo, Italy), Kevin Hurley (University of California, Berkeley, USA), I. Felix Mirabel (ESO), and Leonardo J. Pellizza (Instituto de Astronomia y Fisica del Espacio). The Danish-led team is composed of Johan P. U. Fynbo, Darach Watson, Christina C. Thöne, Tamara M. Davis, Jens Hjorth, José Mará Castro Cerón, Brian L. Jensen, Maximilian D. Stritzinger, and Dong Xu (Dark Cosmology Centre, University of Copenhagen, Denmark), Jesper Sollerman (Dark Cosmology Centre and Department of Astronomy, Stockholm University, Sweden), Uffe G. Jørgensen, Tobias C. Hinse, and Kristian G. Woller (Niels Bohr Institute, University of Copenhagen), Joshua S. Bloom, Daniel Kocevski, Daniel Perley (Department of Astronomy, University of California at Berkeley, USA), Páll Jakobsson (Centre for Astrophysics Research, University of Hertfordshire, UK), John F. Graham and Andrew S. Fruchter (Space Telescope Science Institute, Baltimore, USA), David Bersier (Astrophysics Research Institute, Liverpool John Moores University, UK), Lisa Kewley (University of Hawaii, Institute of Astronomy, USA), Arnaud Cassan and Marta Zub (Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Germany), Suzanne Foley (School of Physics, University College Dublin, Ireland), Javier Gorosabel (Instituto de Astrofisica de Andalucia, Granada, Spain), Keith D. Horne (SUPA Physics/Astronomy, University of St Andrews, Scotland, UK), Sylvio

  11. The VLT Unravels the Nature of the Fastest Binary Star

    NASA Astrophysics Data System (ADS)

    2002-03-01

    wave space experiment, the European Space Agency's Laser Interferometer Space Antenna (LISA) that will be launched in about 10 years' time, will be sufficiently sensitive to be able to reveal this radiation from RX J0806.3+1527 with a high degree of confidence. Such an observational feat would open an entirely new window on the universe. More information The results described in this Press Release were announced in IAU Circular 7835 and will shortly appear in print in the European research journal Astronomy & Astrophysics Letters ("RX J0806.3+1527: a double degenerate binary with the shortest known orbital period (321 s)" by G.L. Israel and co-authors), cf. astro-ph/0203043. The 5-min optical modulation was detected independently by another group led by G. Ramsay, cf. astro-ph/0203053. Note [1]: The team consists of GianLuca Israel and Luigi Stella at the Astronomical Observatory of Rome (Italy), Stefano Covino and Sergio Campana at the Astronomical Observatory of Brera (Milan, Italy), Wolfgang Hummel, Gianni Marconi and Gero Rupprecht at the European Southern Observatory, Immo Appenzeller and Otmar Stahl at the University of Heidelberg (Germany), Wolfgang Gassler and Karl-Heinz Mantel at the University of Munich (Germany), Christopher Mauche at the Lawrence Livermore National Laboratory (USA), Ulisse Munari at the Astronomical Observatory of Padua (Italy), Ignacio Negueruela at the Astronomical Observatory of Strasbourg (France), Harald Nicklas at the University of Göttingen (Germany), and Richard Smart at the Astronomical Observatory of Turin (Italy). [2]: See the research article by Israel et al. (1999, Astronomy &A, Vol. 349, p. L1). Contact GianLuca Israel Osservatorio Astronomico di Roma Italy Tel.: +39 06 9428 6437 email: gianluca@ulysses.mporzio.astro.it Technical information about the photos PR Photo 10a/02 is reproduced from FORS1-exposures, obtained in November 1999 in the U- and R-bands, and both lasting 300 sec. The field measures 2.0 x 1.5 arcmin 2. PR

  12. A systematic search for new X-ray pulsators in ROSAT fields

    NASA Astrophysics Data System (ADS)

    Israel, G. L.

    1996-10-01

    number greatly exceeds the number of serendipitous X-ray sources previously known and catalogued in the Einstein and EXOSAT (about 6000) databases. In this thesis work, based on the results and products contained in the WGA catalogue, we have selected a sample of X-ray sources the light curves of which contained enough photons to carry out a meaningful timing analysis. These light curves were then searched for periodic modulations in a systematic way and a catalogue of candidate X-ray pulsators was created for further detailed study, including optical and X-ray observations. The definition of the sample was based on the minimum number of source photons, 200, that is required to reach a given sensitivity in a search for periodic pulsations with a specified number of trial frequencies. The WGA catalogue contains about 23000 light curves with more than 200 photons. In such a sample, a number of X-ray sources is expected to possess periodic modulation resulting in a power spectrum peak(s). A recently developed technique (Israel & Stella 1996) aimed at the detection of coherent or quasi-coherent signals in presence of additional non-Poissonian noise components in the power spectrum was used and applied to the selected sample of 23000 WGA light curves. The technique was modified and upgraded during this thesis work to take into account the timing problems specific to the ROSAT PSPC data. The ROSAT orbital period (96min) and the oscillations in the pointing direction (402s, ``wobble'') during the observations carried out with the PSPC detector were extensively investigated and, when possible, their effects on the search for periodicity minimised. The timing analysis of the 23000 light curves was performed by means of these techniques in a systematic and automated fashion. Starting from the PSPC light curves a catalogue of pulsator candidates together with the peak and power spectrum parameters was produced. Two different search approaches were adopted: one to cover the largest

  13. Systematic Changes in the Undergraduate Chemistry Curriculum Progam Award and Course and Curriculum Development Program Awards

    NASA Astrophysics Data System (ADS)

    1996-06-01

    and molecules. The graphic images will be combined with interactive benchtop demonstrations and computer animations to produce dynamic visual instructional components (dynamic visualization modules, DVMs) for introductory chemistry courses. The existing instrumentation and modeling facilities required for the project are currently in place. Once developed the DVMs will be tested with approximately 4000 general chemistry students at Arizona State University and the Maricopa Community College system. There is a goal of national dissemination by a commercial publisher once the DVMs have been tested in the local environment. An Introductory Course in Modeling Dynamic Chemical and Ecological Systems. Joseph E. Earley Georgetown University DUE 9554932 99,996 An introductory course in modeling of dynamic systems, with special emphasis on chemical and ecological problems, will be developed. The target student population will be first- and second-year social science and humanities students, but upper division students and interested science majors will not be excluded. Rather than placing emphasis on mathematical methods and techniques used in modeling, attention will be centered on salient aspects of complex-system behavior as illustrated by models constructed using the commercially available software-package STELLA II. Relatively straightforward models dealing with chemical reactions will be used to introduce fundamental features of complex-system dynamics. Problems of ecological and demographic interest, at moderate level of difficulty, will then be covered. The origin and behavior of "deterministic chaos" will be treated using examples from both chemistry and ecology. In the last third of the course, students will work in small groups (or individually) developing their own models, each related to a specific problem of current interest, preferably in fields of the students' major academic interest. Opportunity will be provided for some outstanding students to use less "user

  14. First-Ever Census of Variable Mira-Type Stars in Galaxy Outside the Local Group

    NASA Astrophysics Data System (ADS)

    2003-05-01

    "variable star". The percentage is much higher among large, cool stars ("red giants") - in fact, almost all luminous stars of that type are variable. Such stars are known as Mira-variables ; the name comes from the most prominent member of this class, Omicron Ceti in the constellation Cetus (The Whale), also known as "Stella Mira" (The Wonderful Star). Its brightness changes with a period of 332 days and it is about 1500 times brighter at maximum (visible magnitude 2 and one of the fifty brightest stars in the sky) than at minimum (magnitude 10 and only visible in small telescopes) [2]. Stars like Omicron Ceti are nearing the end of their life. They are very large and have sizes from a few hundred to about a thousand times that of the Sun. The brightness variation is due to pulsations during which the star's temperature and size change dramatically. In the following evolutionary phase, Mira-variables will shed their outer layers into surrounding space and become visible as planetary nebulae with a hot and compact star (a "white dwarf") at the middle of a nebula of gas and dust (cf. the "Dumbbell Nebula" - ESO PR Photo 38a-b/98 ). Several thousand Mira-type stars are currently known in the Milky Way galaxy and a few hundred have been found in other nearby galaxies, including the Magellanic Clouds. The peculiar galaxy Centaurus A ESO PR Photo 14a/03 ESO PR Photo 14a/03 [Preview - JPEG: 400 x 451 pix - 53k [Normal - JPEG: 800 x 903 pix - 528k] [Hi-Res - JPEG: 3612 x 4075 pix - 8.4M] ESO PR Photo 14b/03 ESO PR Photo 14b/03 [Preview - JPEG: 570 x 400 pix - 52k [Normal - JPEG: 1140 x 800 pix - 392k] ESO PR Photo 14c/03 ESO PR Photo 14c/03 [Preview - JPEG: 400 x 451 pix - 61k [Normal - JPEG: 800 x 903 pix - 768k] ESO PR Photo 14d/03 ESO PR Photo 14d/03 [Preview - JPEG: 400 x 451 pix - 56k [Normal - JPEG: 800 x 903 pix - 760k] Captions : PR Photo 14a/03 is a colour composite photo of the peculiar galaxy Centaurus A (NGC 5128) , obtained with the Wide-Field Imager (WFI) camera at