Sir William Rowan Hamilton

Indian Academy of Sciences (India)

IAS Admin

In this picture, wave fronts are defined as surfaces of constant S(x), while .... Recall here that physical quantities are represented in ... his memory imperishable? Hamilton ... self in the words Ptolemy used of Hipparchus: a lover of labour and a ...

Time-advance algorithms based on Hamilton's principle

International Nuclear Information System (INIS)

Lewis, H.R.; Kostelec, P.J.

1993-01-01

Time-advance algorithms based on Hamilton's variational principle are being developed for application to problems in plasma physics and other areas. Hamilton's principle was applied previously to derive a system of ordinary differential equations in time whose solution provides an approximation to the evolution of a plasma described by the Vlasov-Maxwell equations. However, the variational principle was not used to obtain an algorithm for solving the ordinary differential equations numerically. The present research addresses the numerical solution of systems of ordinary differential equations via Hamilton's principle. The basic idea is first to choose a class of functions for approximating the solution of the ordinary differential equations over a specific time interval. Then the parameters in the approximating function are determined by applying Hamilton's principle exactly within the class of approximating functions. For example, if an approximate solution is desired between time t and time t + Δ t, the class of approximating functions could be polynomials in time up to some degree. The issue of how to choose time-advance algorithms is very important for achieving efficient, physically meaningful computer simulations. The objective is to reliably simulate those characteristics of an evolving system that are scientifically most relevant. Preliminary numerical results are presented, including comparisons with other computational methods

Hamilton's indicators of the force of selection

DEFF Research Database (Denmark)

Baudisch, Annette

2005-01-01

To quantify the force of selection, Hamilton [Hamilton, W. D. (1966) J. Theor. Biol. 12, 12-45] derived expressions for the change in fitness with respect to age-specific mutations. Hamilton's indicators are decreasing functions of age. He concluded that senescence is inevitable: survival...... and fertility decline with age. I show that alternative parameterizations of mutational effects lead to indicators that can increase with age. I then consider the case of deleterious mutations with age-specific effects. In this case, it is the balance between mutation and selection pressure that determines...... the equilibrium number of mutations in a population. In this balance, the effects of different parameterizations cancel out, but only to a linear approximation. I show that mutation accumulation has little impact at ages when this linear approximation holds. When mutation accumulation matters, nonlinear effects...

The community takes charge : story and success of Clean Air Hamilton

International Nuclear Information System (INIS)

McCarry, B.

2004-01-01

Clean Air Hamilton was established in 2001 to identify priority air quality issues, pollution sources, and evaluate impacts and solutions for air quality issues. Clean Air Hamilton also assesses the human health effects of ambient air exposures in Hamilton. A 1997 survey of Hamilton residents showed that most citizens were extremely concerned about health effects, black fallout, smog visibility, and odours. Clean Air Hamilton has established an air monitoring network which includes 19 member companies and 22 industrial sites. The objective is to determine recent contaminant trends in upwind/downwind air quality. The timeline for establishing the Hamilton air monitoring network was presented. The network, which serves as a model for Ontario and Canada, monitors the impact of vehicular and industrial emissions and establishes ten-year air quality trends for benzo(a)pyrene, sulphur, nitrogen dioxide, and ozone at industrial sites and the downtown core. Analysis of air quality trends shows that there has been improvement in levels of some locally-generated contaminants. The data has also been used for epidemiological studies to determine the health effects of industry on Hamiltonians. figs

Empty space-times with separable Hamilton-Jacobi equation

International Nuclear Information System (INIS)

Collinson, C.D.; Fugere, J.

1977-01-01

All empty space-times admitting a one-parameter group of motions and in which the Hamilton-Jacobi equation is (partially) separable are obtained. Several different cases of such empty space-times exist and the Riemann tensor is found to be either type D or N. The results presented here complete the search for empty space-times with separable Hamilton-Jacobi equation. (author)

Seismicity related to geothermal development in Dixie Valley, Nevada

Energy Technology Data Exchange (ETDEWEB)

Ryall, A.S.; Vetter, U.R.

1982-07-08

A ten-station seismic network was operated in and around the Dixie Valley area from January 1980 to November 1981; three of these stations are still in operation. Data from the Dixie Valley network were analyzed through 30 Jun 1981, and results of analysis were compared with analysis of somewhat larger events for the period 1970-1979. The seismic cycle in the Western Great Basic, the geologic structural setting, and the instrumentation are also described.

78 FR 9001 - Airworthiness Directives; Hamilton Sundstrand Corporation Propellers

Science.gov (United States)

2013-02-07

... airplane. The Hamilton Sundstrand investigation revealed some of their auxiliary feathering pump motors had internal corrosion that may cause the stator magnets in the pump motor to fail and rotate into the path of... using certain Hamilton Sundstrand Corporation auxiliary pumps and motors (auxiliary feathering pumps...

Solution Hamilton-Jacobi equation for oscillator Caldirola-Kanai

Directory of Open Access Journals (Sweden)

LEONARDO PASTRANA ARTEAGA

2016-12-01

Full Text Available The method allows Hamilton-Jacobi explicitly determine the generating function from which is possible to derive a transformation that makes soluble Hamilton's equations. Using the separation of variables the partial differential equation of the first order called Hamilton-Jacobi equation is solved; as a particular case consider the oscillator Caldirola-Kanai (CK, which is characterized in that the mass presents a temporal evolution exponentially  . We demonstrate that the oscillator CK position presents an exponential decay in time similar to that obtained in the damped sub-critical oscillator, which reflects the dissipation of total mechanical energy. We found that in the limit that the damping factor  is small, the behavior is the same as an oscillator with simple harmonic motion, where the effects of energy dissipation is negligible.

Hamilton-Jacobi Approach to Pre-Big Bang Cosmology at Long-wavelengths

CERN Document Server

Saygili, K

1999-01-01

We apply the long-wavelength approximation to the low energy effective string action in the context of Hamilton-Jacobi theory. The Hamilton-Jacobi equation for the effective string action is explicitly invariant under scale factor duality. We present the leading order, general solution of the Hamilton-Jacobi equation. The Hamilton-Jacobi approach yields a solution consistent with the with the Lagrange formalism. The momentum constraints take an elegant, simple form. Furthermore this general solution reduces to the quasi-isotropic one, if the evolution of the gravitational field is neglected. Duality transformation for the general solution is written as a coordinate transformation in an abstract field space.

A Hamilton-like vector for the special-relativistic Coulomb problem

International Nuclear Information System (INIS)

Munoz, Gerardo; Pavic, Ivana

2006-01-01

A relativistic point charge moving in a Coulomb potential does not admit a conserved Hamilton vector. Despite this fact, a Hamilton-like vector may be developed that proves useful in the derivation and analysis of the particle's orbit

Temperature and Precipitation trends in Kashmir valley, North Western Himalayas

Science.gov (United States)

Shafiq, Mifta Ul; Rasool, Rehana; Ahmed, Pervez; Dimri, A. P.

2018-01-01

Climate change has emerged as an important issue ever to confront mankind. This concern emerges from the fact that our day-to-day activities are leading to impacts on the Earth's atmosphere that has the potential to significantly alter the planet's shield and radiation balance. Developing countries particularly whose income is particularly derived from agricultural activities are at the forefront of bearing repercussions due to changing climate. The present study is an effort to analyze the changing trends of precipitation and temperature variables in Kashmir valley along different elevation zones in the north western part of India. As the Kashmir valley has a rich repository of glaciers with its annual share of precipitation, slight change in the temperature and precipitation regime has far reaching environmental and economic consequences. The results from Indian Meteorological Department (IMD) data of the period 1980-2014 reveals that the annual mean temperature of Kashmir valley has increased significantly. Accelerated warming has been observed during 1980-2014, with intense warming in the recent years (2001-2014). During the period 1980-2014, steeper increase, in annual mean maximum temperature than annual mean minimum temperature, has been observed. In addition, mean maximum temperature in plain regions has shown higher rate of increase when compared with mountainous areas. In case of mean minimum temperature, mountainous regions have shown higher rate of increase. Analysis of precipitation data for the same period shows a decreasing trend with mountainous regions having the highest rate of decrease which can be quite hazardous for the fragile mountain environment of the Kashmir valley housing a large number of glaciers.

Proof of the 1-factorization and Hamilton decomposition conjectures

CERN Document Server

Csaba, Béla; Lo, Allan; Osthus, Deryk; Treglown, Andrew

2016-01-01

In this paper the authors prove the following results (via a unified approach) for all sufficiently large n: (i) [1-factorization conjecture] Suppose that n is even and D\\geq 2\\lceil n/4\\rceil -1. Then every D-regular graph G on n vertices has a decomposition into perfect matchings. Equivalently, \\chi'(G)=D. (ii) [Hamilton decomposition conjecture] Suppose that D \\ge \\lfloor n/2 \\rfloor . Then every D-regular graph G on n vertices has a decomposition into Hamilton cycles and at most one perfect matching. (iii) [Optimal packings of Hamilton cycles] Suppose that G is a graph on n vertices with minimum degree \\delta\\ge n/2. Then G contains at least {\\rm reg}_{\\rm even}(n,\\delta)/2 \\ge (n-2)/8 edge-disjoint Hamilton cycles. Here {\\rm reg}_{\\rm even}(n,\\delta) denotes the degree of the largest even-regular spanning subgraph one can guarantee in a graph on n vertices with minimum degree \\delta. (i) was first explicitly stated by Chetwynd and Hilton. (ii) and the special case \\delta= \\lceil n/2 \\rceil of (iii) answe...

Generally covariant Hamilton-Jacobi equation and rotated liquid sphere metrics

International Nuclear Information System (INIS)

Abdil'din, M.M.; Abdulgafarov, M.K.; Abishev, M.E.

2005-01-01

In the work Lense-Thirring problem on corrected Fock's first approximation metrics by Hamilton-Jacobi method considered. Generally covariant Hamilton-Jacobi equation had been sold by separation of variable method. Path equation of probe particle motion in rotated liquid sphere field is obtained. (author)

The Magnus problem in Rodrigues-Hamilton parameters

Science.gov (United States)

Koshliakov, V. N.

1984-04-01

The formalism of Rodrigues-Hamilton parameters is applied to the Magnus problem related to the systematic drift of a gimbal-mounted astatic gyroscope due to the nutational vibration of the main axis of the rotor. It is shown that the use of the above formalism makes it possible to limit the analysis to a consideration of a linear system of differential equations written in perturbed values of Rodrigues-Hamilton parameters. A refined formula for the drift of the main axis of the gyroscope rotor is obtained, and an estimation is made of the effect of the truncation of higher-order terms.

Hamilton-Jacobi theorems for regular reducible Hamiltonian systems on a cotangent bundle

Science.gov (United States)

Wang, Hong

2017-09-01

In this paper, some of formulations of Hamilton-Jacobi equations for Hamiltonian system and regular reduced Hamiltonian systems are given. At first, an important lemma is proved, and it is a modification for the corresponding result of Abraham and Marsden (1978), such that we can prove two types of geometric Hamilton-Jacobi theorem for a Hamiltonian system on the cotangent bundle of a configuration manifold, by using the symplectic form and dynamical vector field. Then these results are generalized to the regular reducible Hamiltonian system with symmetry and momentum map, by using the reduced symplectic form and the reduced dynamical vector field. The Hamilton-Jacobi theorems are proved and two types of Hamilton-Jacobi equations, for the regular point reduced Hamiltonian system and the regular orbit reduced Hamiltonian system, are obtained. As an application of the theoretical results, the regular point reducible Hamiltonian system on a Lie group is considered, and two types of Lie-Poisson Hamilton-Jacobi equation for the regular point reduced system are given. In particular, the Type I and Type II of Lie-Poisson Hamilton-Jacobi equations for the regular point reduced rigid body and heavy top systems are shown, respectively.

78 FR 73750 - Proposed Amendment of Class E Airspace; Hamilton, OH

Science.gov (United States)

2013-12-09

...: Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed rulemaking (NPRM). SUMMARY: This action proposes to amend Class E airspace at Hamilton, OH. Decommissioning of the Hamilton nondirectional... the views and suggestions presented are particularly helpful in developing reasoned regulatory...

Microscopic Identification of Prokaryotes in Modern and Ancient Halite, Saline Valley and Death Valley, California

Science.gov (United States)

Schubert, Brian A.; Lowenstein, Tim K.; Timofeeff, Michael N.

2009-06-01

Primary fluid inclusions in halite crystallized in Saline Valley, California, in 1980, 2004-2005, and 2007, contain rod- and coccoid-shaped microparticles the same size and morphology as archaea and bacteria living in modern brines. Primary fluid inclusions from a well-dated (0-100,000 years), 90 m long salt core from Badwater Basin, Death Valley, California, also contain microparticles, here interpreted as halophilic and halotolerant prokaryotes. Prokaryotes are distinguished from crystals on the basis of morphology, optical properties (birefringence), and uniformity of size. Electron micrographs of microparticles from filtered modern brine (Saline Valley), dissolved modern halite crystals (Saline Valley), and dissolved ancient halite crystals (Death Valley) support in situ microscopic observations that prokaryotes are present in fluid inclusions in ancient halite. In the Death Valley salt core, prokaryotes in fluid inclusions occur almost exclusively in halite precipitated in perennial saline lakes 10,000 to 35,000 years ago. This suggests that trapping and preservation of prokaryotes in fluid inclusions is influenced by the surface environment in which the halite originally precipitated. In all cases, prokaryotes in fluid inclusions in halite from the Death Valley salt core are miniaturized (<1 μm diameter cocci, <2.5 μm long, very rare rod shapes), which supports interpretations that the prokaryotes are indigenous to the halite and starvation survival may be the normal response of some prokaryotes to entrapment in fluid inclusions for millennia. These results reinforce the view that fluid inclusions in halite and possibly other evaporites are important repositories of microbial life and should be carefully examined in the search for ancient microorganisms on Earth, Mars, and elsewhere in the Solar System.

A generalization of Hamilton's rule--love others how much?

Science.gov (United States)

Alger, Ingela; Weibull, Jörgen W

2012-04-21

According to Hamilton's (1964a, b) rule, a costly action will be undertaken if its fitness cost to the actor falls short of the discounted benefit to the recipient, where the discount factor is Wright's index of relatedness between the two. We propose a generalization of this rule, and show that if evolution operates at the level of behavior rules, rather than directly at the level of actions, evolution will select behavior rules that induce a degree of cooperation that may differ from that predicted by Hamilton's rule as applied to actions. In social dilemmas there will be less (more) cooperation than under Hamilton's rule if the actions are strategic substitutes (complements). Our approach is based on natural selection, defined in terms of personal (direct) fitness, and applies to a wide range of pairwise interactions. Copyright © 2011 Elsevier Ltd. All rights reserved.

Beyond WKB quantum corrections to Hamilton-Jacobi theory

International Nuclear Information System (INIS)

Jurisch, Alexander

2007-01-01

In this paper, we develop quantum mechanics of quasi-one-dimensional systems upon the framework of the quantum-mechanical Hamilton-Jacobi theory. We will show that the Schroedinger point of view and the Hamilton-Jacobi point of view are fully equivalent in their description of physical systems, but differ in their descriptive manner. As a main result of this, a wavefunction in Hamilton-Jacobi theory can be decomposed into travelling waves in any point in space, not only asymptotically. Using the quasi-linearization technique, we derive quantum correction functions in every order of h-bar. The quantum correction functions will remove the turning-point singularity that plagues the WKB-series expansion already in zeroth order and thus provide an extremely good approximation to the full solution of the Schroedinger equation. In the language of quantum action it is also possible to elegantly solve the connection problem without asymptotic approximations. The use of quantum action further allows us to derive an equation by which the Maslov index is directly calculable without any approximations. Stationary quantum trajectories will also be considered and thoroughly discussed

Interrelations among pyroclastic surge, pyroclastic flow, and lahars in Smith Creek valley during first minutes of 18 May 1980 eruption of Mount St. Helens, USA

Science.gov (United States)

Brantley, S.R.; Waitt, R.B.

1988-01-01

A devastating pyroclastic surge and resultant lahars at Mount St. Helens on 18 May 1980 produced several catastrophic flowages into tributaries on the northeast volcano flank. The tributaries channeled the flows to Smith Creek valley, which lies within the area devastated by the surge but was unaffected by the great debris avalanche on the north flank. Stratigraphy shows that the pyroclastic surge preceded the lahars; there is no notable "wet" character to the surge deposits. Therefore the lahars must have originated as snowmelt, not as ejected water-saturated debris that segregated from the pyroclastic surge as has been inferred for other flanks of the volcano. In stratigraphic order the Smith Creek valley-floor materials comprise (1) a complex valley-bottom facies of the pyroclastic surge and a related pyroclastic flow, (2) an unusual hummocky diamict caused by complex mixing of lahars with the dry pyroclastic debris, and (3) deposits of secondary pyroclastic flows. These units are capped by silt containing accretionary lapilli, which began falling from a rapidly expanding mushroom-shaped cloud 20 minutes after the eruption's onset. The Smith Creek valley-bottom pyroclastic facies consists of (a) a weakly graded basal bed of fines-poor granular sand, the deposit of a low-concentration lithic pyroclastic surge, and (b) a bed of very poorly sorted pebble to cobble gravel inversely graded near its base, the deposit of a high-concentration lithic pyroclastic flow. The surge apparently segregated while crossing the steep headwater tributaries of Smith Creek; large fragments that settled from the turbulent surge formed a dense pyroclastic flow along the valley floor that lagged behind the front of the overland surge. The unusual hummocky diamict as thick as 15 m contains large lithic clasts supported by a tough, brown muddy sand matrix like that of lahar deposits upvalley. This unit contains irregular friable lenses and pods meters in diameter, blocks incorporated from

El distribuidor de trafico de Hamilton-Inglaterra

Directory of Open Access Journals (Sweden)

Babtie Shaw and Morton, Ingenieros Consultores

1969-06-01

Full Text Available The first part of this article describes the initial stages in the construction of the complex traffic interchange at Hamilton, and gives details of all the special aspects which it involves. The second part deals with two of the three bridges at the Maryville interchange, and a detailed description is given of the most important features of these structures.La primera parte de este artículo muestra el trabajo de la primera etapa del complejo del distribuidor de tráfico de Hamilton, dándonos cuenta de las obras que engloba. La segunda parte trata de dos de los tres puentes que hay en el empalme de Maryville, describiéndolos y mostrando sus partes más importantes.

Convergent Difference Schemes for Hamilton-Jacobi equations

KAUST Repository

Duisembay, Serikbolsyn

2018-01-01

In this thesis, we consider second-order fully nonlinear partial differential equations of elliptic type. Our aim is to develop computational methods using convergent difference schemes for stationary Hamilton-Jacobi equations with Dirichlet

Convergent Difference Schemes for Hamilton-Jacobi equations

KAUST Repository

Duisembay, Serikbolsyn

2018-05-07

In this thesis, we consider second-order fully nonlinear partial differential equations of elliptic type. Our aim is to develop computational methods using convergent difference schemes for stationary Hamilton-Jacobi equations with Dirichlet and Neumann type boundary conditions in arbitrary two-dimensional domains. First, we introduce the notion of viscosity solutions in both continuous and discontinuous frameworks. Next, we review Barles-Souganidis approach using monotone, consistent, and stable schemes. In particular, we show that these schemes converge locally uniformly to the unique viscosity solution of the first-order Hamilton-Jacobi equations under mild assumptions. To solve the scheme numerically, we use Euler map with some initial guess. This iterative method gives the viscosity solution as a limit. Moreover, we illustrate our numerical approach in several two-dimensional examples.

Regularization of Hamilton-Lagrangian guiding center theories

International Nuclear Information System (INIS)

Correa-Restrepo, D.; Wimmel, H.K.

1985-04-01

The Hamilton-Lagrangian guiding-center (G.C.) theories of Littlejohn, Wimmel, and Pfirsch show a singularity for B-fields with non-vanishing parallel curl at a critical value of vsub(parallel), which complicates applications. The singularity is related to a sudden breakdown, at a critical vsub(parallel), of gyration in the exact particle mechanics. While the latter is a real effect, the G.C. singularity can be removed. To this end a regularization method is defined that preserves the Hamilton-Lagrangian structure and the conservation theorems. For demonstration this method is applied to the standard G.C. theory (without polarization drift). Liouville's theorem and G.C. kinetic equations are also derived in regularized form. The method could equally well be applied to the case with polarization drift and to relativistic G.C. theory. (orig.)

Algebra and Geometry of Hamilton's Quaternions

Indian Academy of Sciences (India)

2016-08-26

Aug 26, 2016 ... ... Public Lectures · Lecture Workshops · Refresher Courses · Symposia. Home; Journals; Resonance – Journal of Science Education; Volume 21; Issue 6. Algebra and Geometry of Hamilton's Quaternions: 'Well, Papa, Can You Multiply Triplets?' General Article Volume 21 Issue 6 June 2016 pp 529-544 ...

Unified Symmetry of Hamilton Systems

International Nuclear Information System (INIS)

Xu Xuejun; Qin Maochang; Mei Fengxiang

2005-01-01

The definition and the criterion of a unified symmetry for a Hamilton system are presented. The sufficient condition under which the Noether symmetry is a unified symmetry for the system is given. A new conserved quantity, as well as the Noether conserved quantity and the Hojman conserved quantity, deduced from the unified symmetry, is obtained. An example is finally given to illustrate the application of the results.

[Anna Hamilton (1864-1935), the excellence of nursing.

Science.gov (United States)

Diebolt, Évelyne

2017-12-01

A Frenchwoman, Anna Hamilton (1864-1935), daughter of a Franco-English couple, reads with passion the works of Florence Nightingale and takes an interest in nursing. In order to practice it, she first passes the equivalent of a bachelor’s degree in self-education and registers at the Marseille medical school. She wants to prepare a medical thesis on the nursing staff in the hospitals in Europe and is conducting an investigation throughout Europe. She passed her thesis on June 15, 1900 entitled “Considerations on hospital nurses”. This work is immediately published. That same year, she took up a post at the “Maison de santé protestante” in Bordeaux (MSP), founded in 1863. Without managerial staff, she is forced to recruit them abroad. She publishes a professional journal : “La Garde-Malade hospitalière” (1906-1914). Then the war turned the MSP into a military hospital, but the institution continued to receive local paying patients. She was given permission to call the school of nurses : Florence Nightingale School. Anna Hamilton is working with American women to create a medical and social service in Aisne. A graduate, Antoinette Hervey, then opened a medical-social service in Rouen, which would employ up to 30 visiting nurses. In 1916, the MSP received a donation from the domain of Bagatelle. The board of directors wants to sell it, but Anna Hamilton manages to finance a hospital-school thanks to families bereaved by the war and a subscription announced in the “Journal of Nursing”. Other establishments created by former students of the MSP opened : the School-hospital Ambroise Paré in Lille, a nursing home for nurses in Chambon-sur-Lignon in 1927 (the Edith-Seltzer foundation) and a sanatorium in Briançon. After a busy life, Anna Hamilton died of cancer in 1935 and is buried in Bordeaux.

Hamilton Utilities Corporation annual report 2002 : people, performance, productivity : the business of public service

International Nuclear Information System (INIS)

2002-01-01

A brief overview of the municipally-owned Hamilton Utilities Corporation was provided. When Ontario's electricity market opened to competition, it allowed wholesale and retail electricity marketers to operate on a competitive basis. This report describes how Hamilton Hydro, the largest subsidiary, successfully faced the challenges brought about by the open market. The strategy of growth as a multi-utility corporation progressed significantly. Major financial restructuring was completed, income level was maintained, as well as a strong balance sheet. The construction of Hamilton's first district energy system was effected by Hamilton Community Energy, another subsidiary. This project is expected to provide heat to 10 buildings in the downtown area, producing 3.5 megawatts of electricity for the City. The third subsidiary, FibreWired, applied its vast communications expertise to the health care sector. It offered Virtual Private Network (VPN) services to area hospitals and other health care providers in pharmaceutical and biotechnology. A major study was undertaken jointly with the City of Hamilton. It examined the feasibility of restructuring water and wastewater services into a municipally owned corporation under the umbrella of Hamilton Utilities Corporation. Various examples were provided throughout the report to better illustrate how corporate vision was translated into reality. tabs

Hamilton's principle for beginners

International Nuclear Information System (INIS)

Brun, J L

2007-01-01

I find that students have difficulty with Hamilton's principle, at least the first time they come into contact with it, and therefore it is worth designing some examples to help students grasp its complex meaning. This paper supplies the simplest example to consolidate the learning of the quoted principle: that of a free particle moving along a line. Next, students are challenged to add gravity to reinforce the argument and, finally, a two-dimensional motion in a vertical plane is considered. Furthermore these examples force us to be very clear about such an abstract principle

Hamilton-Jacobi equations and brane associated Lagrangians

International Nuclear Information System (INIS)

Baker, L.M.; Fairlie, D.B.

2001-01-01

This article seeks to relate a recent proposal for the association of a covariant Field Theory with a string or brane Lagrangian to the Hamilton-Jacobi formalism for strings and branes. It turns out that since in this special case, the Hamiltonian depends only upon the momenta of the Jacobi fields and not the fields themselves, it is the same as a Lagrangian, subject to a constancy constraint. We find that the associated Lagrangians for strings or branes have a covariant description in terms of the square root of the same Lagrangian. If the Hamilton-Jacobi function is zero, rather than a constant, then it is in in one dimension lower, reminiscent of the 'holographic' idea. In the second part of the paper, we discuss properties of these Lagrangians, which lead to what we have called 'Universal Field Equations', characteristic of covariant equations of motion

Measuring Social Capital in Hamilton, Ontario

Science.gov (United States)

Kitchen, Peter; Williams, Allison; Simone, Dylan

2012-01-01

Social capital has been studied by academics for more than 20 years and within the past decade there has been an explosion of growth in research linking social capital to health. This paper investigates social capital in Hamilton, Ontario by way of a telephone survey of 1,002 households in three neighbourhood groups representing high, mixed and…

Hamilton and Hardy: Mentoring and Friendship in the Service of Occupational Health.

Science.gov (United States)

Sullivan, Marianne

This article explores the mentoring relationship between Alice Hamilton and Harriet Hardy, two female physician-researchers who had a tremendous impact on the development of the field of occupational health in the United States during the 20th century. The article relies on letters the women wrote to each other. Hamilton, the elder, supported and furthered Hardy's career by asking her to coauthor the second edition of a seminal occupational health text. After beginning this intellectual collaboration, Hamilton remained a mentor to Hardy, and a decades-long friendship ensued. The article explores their relationship within the historical, political, and social context in which the women worked and made remarkable contributions to public health.

Nonlinear H-infinity control, Hamiltonian systems and Hamilton-Jacobi equations

CERN Document Server

Aliyu, MDS

2011-01-01

A comprehensive overview of nonlinear Haeu control theory for both continuous-time and discrete-time systems, Nonlinear Haeu-Control, Hamiltonian Systems and Hamilton-Jacobi Equations covers topics as diverse as singular nonlinear Haeu-control, nonlinear Haeu -filtering, mixed H2/ Haeu-nonlinear control and filtering, nonlinear Haeu-almost-disturbance-decoupling, and algorithms for solving the ubiquitous Hamilton-Jacobi-Isaacs equations. The link between the subject and analytical mechanics as well as the theory of partial differential equations is also elegantly summarized in a single chapter

Researcher Profile: An Interview with Axton Betz-Hamilton

Directory of Open Access Journals (Sweden)

Axton Betz-Hamilton

2015-07-01

Full Text Available Dr. Axton Betz-Hamilton teaches consumer studies courses at Eastern Illinois University, including Personal and Family Finance, Housing, and Consumer Issues. She conducts research on identity theft as well as financial abuse within families.

Geothermal resource assessment of western San Luis Valley, Colorado

Energy Technology Data Exchange (ETDEWEB)

Zacharakis, Ted G.; Pearl, Richard Howard; Ringrose, Charles D.

1983-01-01

The Colorado Geological Survey initiated and carried out a fully integrated assessment program of the geothermal resource potential of the western San Luis Valley during 1979 and 1980. The San Luis Valley is a large intermontane basin located in southcentral Colorado. While thermal springs and wells are found throughout the Valley, the only thermal waters found along the western part of the Valley are found at Shaw Warm Springs which is a relatively unused spring located approximately 6 miles (9.66 km) north of Del Norte, Colorado. The waters at Shaws Warm Spring have a temperature of 86 F (30 C), a discharge of 40 gallons per minute and contain approximately 408 mg/l of total dissolved solids. The assessment program carried out din the western San Luis Valley consisted of: soil mercury geochemical surveys; geothermal gradient drilling; and dipole-dipole electrical resistivity traverses, Schlumberger soundings, Audio-magnetotelluric surveys, telluric surveys, and time-domain electro-magnetic soundings and seismic surveys. Shaw Warm Springs appears to be the only source of thermal waters along the western side of the Valley. From the various investigations conducted the springs appear to be fault controlled and is very limited in extent. Based on best evidence presently available estimates are presented on the size and extent of Shaw Warm Springs thermal system. It is estimated that this could have an areal extent of 0.63 sq. miles (1.62 sq. km) and contain 0.0148 Q's of heat energy.

Cocaleros. Violence, Drugs and Social Mobilization in the Post-Conflict Upper Huallaga Valley, Peru

NARCIS (Netherlands)

van Dun, M.E.H.

2009-01-01

During Peru’s internal armed conflict (1980s-1990s) the Upper Huallaga Valley became one of the most violent theaters of conflict, with political violence and violent crime becoming causally related phenomena. In the Upper Huallaga different sorts of armed actors (whether their motivations were

Hamiltonization of theories with degenerate coordinates

International Nuclear Information System (INIS)

Gitman, D.M.; Tyutin, I.V.

2002-01-01

We consider a class of Lagrangian theories where part of the coordinates does not have any time derivatives in the Lagrange function (we call such coordinates degenerate). We advocate that it is reasonable to reconsider the conventional definition of singularity based on the usual Hessian and, moreover, to simplify the conventional hamiltonization procedure. In particular, in such a procedure, it is not necessary to complete the degenerate coordinates with the corresponding conjugate momenta

Hamiltonization of theories with degenerate coordinates

Energy Technology Data Exchange (ETDEWEB)

Gitman, D.M. E-mail: gitman@fma.if.usp.br; Tyutin, I.V. E-mail: tyutin@lpi.ru

2002-05-27

We consider a class of Lagrangian theories where part of the coordinates does not have any time derivatives in the Lagrange function (we call such coordinates degenerate). We advocate that it is reasonable to reconsider the conventional definition of singularity based on the usual Hessian and, moreover, to simplify the conventional hamiltonization procedure. In particular, in such a procedure, it is not necessary to complete the degenerate coordinates with the corresponding conjugate momenta.

'From Man to Bacteria': W.D. Hamilton, the theory of inclusive fitness, and the post-war social order.

Science.gov (United States)

Swenson, Sarah A

2015-02-01

W.D. Hamilton's theory of inclusive fitness aimed to define the evolved limits of altruism with mathematical precision. Although it was meant to apply universally, it has been almost irretrievably entwined with the particular case of social insects that featured in his famous 1964 papers. The assumption that social insects were central to Hamilton's early work contradicts material in his rich personal archive. In fact, careful study of Hamilton's notes, letters, diaries, and early essays indicates the extent to which he had humans in mind when he decided altruism was a topic worthy of biological inquiry. For this reason, this article reconsiders the role of extra-scientific factors in Hamilton's early theorizing. In doing so, it offers an alternative perspective as to why Hamilton saw self-sacrifice to be an important subject. Although the traditional narrative prioritizes his distaste for benefit-of-the-species explanations as a motivating factor behind his foundational work, I argue that greater attention ought to be given to Hamilton's hope that science could be used to address social ills. By reconsidering the meaning Hamilton intended inclusive fitness to have, we see that while he was no political ideologue, the socio-political relevance of his theory was nevertheless integral to its development. Copyright © 2015 Elsevier Ltd. All rights reserved.

Groundwater availability of the Central Valley Aquifer, California

Science.gov (United States)

Faunt, Claudia C.

2009-01-01

California's Central Valley covers about 20,000 square miles and is one of the most productive agricultural regions in the world. More than 250 different crops are grown in the Central Valley with an estimated value of $17 billion per year. This irrigated agriculture relies heavily on surface-water diversions and groundwater pumpage. Approximately one-sixth of the Nation's irrigated land is in the Central Valley, and about one-fifth of the Nation's groundwater demand is supplied from its aquifers. The Central Valley also is rapidly becoming an important area for California's expanding urban population. Since 1980, the population of the Central Valley has nearly doubled from 2 million to 3.8 million people. The Census Bureau projects that the Central Valley's population will increase to 6 million people by 2020. This surge in population has increased the competition for water resources within the Central Valley and statewide, which likely will be exacerbated by anticipated reductions in deliveries of Colorado River water to southern California. In response to this competition for water, a number of water-related issues have gained prominence: conservation of agricultural land, conjunctive use, artificial recharge, hydrologic implications of land-use change, and effects of climate variability. To provide information to stakeholders addressing these issues, the USGS Groundwater Resources Program made a detailed assessment of groundwater availability of the Central Valley aquifer system, that includes: (1) the present status of groundwater resources; (2) how these resources have changed over time; and (3) tools to assess system responses to stresses from future human uses and climate variability and change. This effort builds on previous investigations, such as the USGS Central Valley Regional Aquifer System and Analysis (CV-RASA) project and several other groundwater studies in the Valley completed by Federal, State and local agencies at differing scales. The

Current status of research and development of 99Mo/99mTc generator in Korea

International Nuclear Information System (INIS)

Park, U.J.; Lee, J.S.; Son, K.J.; Nam, S.S.; Kwak, S.I.; Han, H.S.

2006-01-01

To supply 99m Tc in stable and economical manner in Korea, a chromatographic generator has been under development at KAERI since late 1980's. The chromatographic type of technetium generator is preferred in hospital because it is more convenient and less time-restricted for applications. Hence, the demand of 99m Tc in medical applications is keep increasing. In Korea, there are more than 200 gamma cameras including SPECT in hospitals. For these applications, approximately 100 units/week of 99m Tc generators of which annual cost reached 3 million US dollars were required in 2002. Hence, the development of 99m Tc generators and technology of fission 99 Mo processing were started while installing the generator loading facility (GLF) at KAERI. This facility is currently on a trial run for the commercial production of 99m Tc generators and expected to produce more than 200 generators per week in 2004. For the fission 99 Mo production, an annulus U foil target was considered as the LEU target. The designed LEU target is being used for target manufacturing test and accident analysis. The develop gel type 99m Tc generators by using a poly zirconium complex (PZC) and alumina column, KAERI has cooperated with a Japanese company since late 1990's. In 2003, experimental studies for molybdate adsorption capacity and elution characteristics of the PZC samples from three different batches produced by Kaken Co. were carried out. (author)

Bibliography of Soviet Laser Developments, Number 47, May - June 1980.

Science.gov (United States)

1981-04-09

23 p. (KL, 19/80, 17050) 99 IV. SOURCE ABBREVIATIONS (CIRC Codens) APP (A) (ATPLB) Acta physica polonica BAPS (BAPTA) Bulletin de l’Academie Polonaise...obraztsy, tovarnyye znaki PSS (PSSAB) Physica Status Solidi (A). Applied Research PTE (PRTEA) Pribory i tekhnika eksperimenta RiE (RAELA) Radiotekhnika i

Examining Spatiotemporal Urbanization Patterns in Kathmandu Valley, Nepal: Remote Sensing and Spatial Metrics Approaches

Directory of Open Access Journals (Sweden)

Rajesh Bahadur Thapa

2009-09-01

Full Text Available This paper examines the spatiotemporal pattern of urbanization in Kathmandu Valley using remote sensing and spatial metrics techniques. The study is based on 33-years of time series data compiled from satellite images. Along with new developments within the city fringes and rural villages in the valley, shifts in the natural environment and newly developed socioeconomic strains between residents are emerging. A highly dynamic spatial pattern of urbanization is observed in the valley. Urban built-up areas had a slow trend of growth in the 1960s and 1970s but have grown rapidly since the 1980s. The urbanization process has developed fragmented and heterogeneous land use combinations in the valley. However, the refill type of development process in the city core and immediate fringe areas has shown a decreasing trend in the neighborhood distances between land use patches, and an increasing trend towards physical connectedness, which indicates a higher probability of homogenous landscape development in the upcoming decades.

Safety evaluation report related to the operation of Sequoyah Nuclear Plant, Units 1 and 2, Docket Nos. 50-327 and 50-328, Tennessee Valley Authority

International Nuclear Information System (INIS)

1982-12-01

Supplement No. 6 to the Safety Evaluation Report (SER) related to the operation of the Tennessee Valley Authority's Sequoyah Nuclear Plant, Units 1 and 2, located in Hamilton County, Tennessee, has been prepared by the Office of Nuclear Reactor Regulation of the US Nuclear Regulatory Commission. The purpose of this supplement is to update the staff's evaluations of the issues related to the hydrogen mitigation system identified in the SER and previous supplements as needing resolution

Higher order derivatives via Hamilton-Jacobi approach

International Nuclear Information System (INIS)

Bertin, M.C.; Pimentel, B.M.; Pompeia, P.J.

2006-01-01

In this work we will show how can be derived a general method for dealing with Lagrangians containing high order derivatives using the Hamilton-Jacobi Formalism for singular systems. By the expansion the configuration space of a n dimensional system we will be able to introduce first order actions and build the equations of motion of the system. We will work with the Generalized Electrodynamics of Podolsky as an example. (author)

Safety evaluation report related to the operation of Sequoyah Nuclear Plant, Units 1 and 2, Docket Nos. 50-327 and 50-328, Tennessee Valley Authority. Supplement No. 4

Energy Technology Data Exchange (ETDEWEB)

NONE

1981-01-01

On September 17, 1980, the Nuclear Regulatory Commission (NRC) issued the facility operating license DPR-77 to the Tennessee Valley Authority for the Sequoyah Nuclear Plant, Unit 1, located in Hamilton County, Tennessee. The license authorized operation of Unit 1 at 100 percent power; however, a license condition regarding the adequacy of the hydrogen control system was included that required resolution by January 31, 1981. The purpose of Supplement No. 4 to the SER is to further update our Safety Evaluation Reports on the hydrogen control measures (Section 22.2, II.B.7), and to comply with the license condition which is as follows: 'By January 31, 1981, TVA shall by testing and analysis show to the satisfaction of the NRC staff that an interim hydrogen control system will provide with reasonable assurance protection against breach of containment in the event that a substantial quantity of hydrogen is generated.' TVA submitted on December 11, 1980, the first quarterly report on the research program for hydrogen control. Also, TVA revised volume 2 of the Sequoyah Core Degradation Program Report to incorporate additional information on the overall program. Section II.B.7 of Supplement No. 4 responds to the license condition. Each section is supplementary to and not in lieu of discussion in the Safety Evaluation Report and Supplements Nos. 1, 2, and 3, except where specifically noted. Supplements No. 2 and 3 to the Safety Evaluation Report provided a basis for concluding that the full-power licensing of Sequoyah Unit 1 need not await completion of ongoing work on hydrogen control measures. This supplement concludes that operation of the IDIS for an interim period of one year is appropriate.

The future supply of molybdenum-99

International Nuclear Information System (INIS)

Rojas-Burke, J.

1995-01-01

Since 1991, nuclear medicine physicians across the United States and much of the world have relied entirely on one 38-year-old nuclear reactor in Canada for the production of 99 Mo, the isotope used in 99m Tc generators. This situation came about quietly in the 1980s as alternate suppliers dropped out of the market, leaving Nordion International Inc. in Kanata, Ontario as the major supplier in the world. While Nordion has managed to maintain a steady supply of the essential material to radiopharmaceutical makers, a series of reactor failures and labor disputes have come close to halting production several times at the facilities that produce isotopes for Nordion in Chalk River, Ontario. 1 fig., 1 tab

Durand Neighbourhood Heritage Inventory: Toward a Digital Citywide Survey Approach to Heritage Planning in Hamilton

Science.gov (United States)

Angel, V.; Garvey, A.; Sydor, M.

2017-08-01

In the face of changing economies and patterns of development, the definition of heritage is diversifying, and the role of inventories in local heritage planning is coming to the fore. The Durand neighbourhood is a layered and complex area located in inner-city Hamilton, Ontario, Canada, and the second subject area in a set of pilot inventory studies to develop a new city-wide inventory strategy for the City of Hamilton,. This paper presents an innovative digital workflow developed to undertake the Durand Built Heritage Inventory project. An online database was developed to be at the centre of all processes, including digital documentation, record management, analysis and variable outputs. Digital tools were employed for survey work in the field and analytical work in the office, resulting in a GIS-based dataset that can be integrated into Hamilton's larger municipal planning system. Together with digital mapping and digitized historical resources, the Durand database has been leveraged to produce both digital and static outputs to shape recommendations for the protection of Hamilton's heritage resources.

Game theory to characterize solutions of a discrete-time Hamilton-Jacobi equation

International Nuclear Information System (INIS)

Toledo, Porfirio

2013-01-01

We study the behavior of solutions of a discrete-time Hamilton-Jacobi equation in a minimax framework of game theory. The solutions of this problem represent the optimal payoff of a zero-sum game of two players, where the number of moves between the players converges to infinity. A real number, called the critical value, plays a central role in this work; this number is the asymptotic average action of optimal trajectories. The aim of this paper is to show the existence and characterization of solutions of a Hamilton-Jacobi equation for this kind of games

A generalization of Hamilton's rule for the evolution of microbial cooperation.

Science.gov (United States)

Smith, Jeff; Van Dyken, J David; Zee, Peter C

2010-06-25

Hamilton's rule states that cooperation will evolve if the fitness cost to actors is less than the benefit to recipients multiplied by their genetic relatedness. This rule makes many simplifying assumptions, however, and does not accurately describe social evolution in organisms such as microbes where selection is both strong and nonadditive. We derived a generalization of Hamilton's rule and measured its parameters in Myxococcus xanthus bacteria. Nonadditivity made cooperative sporulation remarkably resistant to exploitation by cheater strains. Selection was driven by higher-order moments of population structure, not relatedness. These results provide an empirically testable cooperation principle applicable to both microbes and multicellular organisms and show how nonlinear interactions among cells insulate bacteria against cheaters.

Numerical Solution of Hamilton-Jacobi Equations in High Dimension

Science.gov (United States)

2012-11-23

high dimension FA9550-10-1-0029 Maurizio Falcone Dipartimento di Matematica SAPIENZA-Universita di Roma P. Aldo Moro, 2 00185 ROMA AH930...solution of Hamilton-Jacobi equations in high dimension AFOSR contract n. FA9550-10-1-0029 Maurizio Falcone Dipartimento di Matematica SAPIENZA

Lie-Hamilton systems on curved spaces: a geometrical approach

Science.gov (United States)

Herranz, Francisco J.; de Lucas, Javier; Tobolski, Mariusz

2017-12-01

A Lie-Hamilton system is a nonautonomous system of first-order ordinary differential equations describing the integral curves of a t-dependent vector field taking values in a finite-dimensional Lie algebra, a Vessiot-Guldberg Lie algebra, of Hamiltonian vector fields relative to a Poisson structure. Its general solution can be written as an autonomous function, the superposition rule, of a generic finite family of particular solutions and a set of constants. We pioneer the study of Lie-Hamilton systems on Riemannian spaces (sphere, Euclidean and hyperbolic plane), pseudo-Riemannian spaces (anti-de Sitter, de Sitter, and Minkowski spacetimes) as well as on semi-Riemannian spaces (Newtonian spacetimes). Their corresponding constants of motion and superposition rules are obtained explicitly in a geometric way. This work extends the (graded) contraction of Lie algebras to a contraction procedure for Lie algebras of vector fields, Hamiltonian functions, and related symplectic structures, invariants, and superposition rules.

Remediating the South Alligator Valley uranium mining legacy

International Nuclear Information System (INIS)

Fawcett, M.; Waggitt, P.

2010-01-01

In late 1950s and early 1960s 13 uranium mines operated in the South Alligator Valley of Australia's Northern Territory. Once sales contracts had been filled the mines were abandoned and no remediation took place. In the 1980s the valley was designated as part of Stage 3 of the adjacent World Heritage-listed, Kakadu National Park. Proposals for remediation were only seriously put forward when the land was returned to the traditional Aboriginal owners, the Gunlom Land Trust, in 1996. Although they leased the land back so it would remain a part of Kakadu National Park the traditional Aboriginal owners required remediation to be complete by 2015. This paper tells the story of the development and implementation of the remediation process from the start of planning in 1998 to completion in 2009; and finally it describes the development of stakeholder relationships and the initial plans for long term stewardship. (author)

The integrated melter off-gas treatment systems at the West Valley Demonstration Project

International Nuclear Information System (INIS)

Vance, R.F.

1991-12-01

The West Valley Demonstration project was established by an act of Congress in 1980 to solidify the high level radioactive liquid wastes produced from operation of the Western New York Nuclear Services Center from 1966 to 1972. The waste will be solidified as borosilicate glass. This report describes the functions, the controlling design criteria, and the resulting design of the melter off-gas treatment systems

Water resources of Parowan Valley, Iron County, Utah

Science.gov (United States)

Marston, Thomas M.

2017-08-29

Parowan Valley, in Iron County, Utah, covers about 160 square miles west of the Red Cliffs and includes the towns of Parowan, Paragonah, and Summit. The valley is a structural depression formed by northwest-trending faults and is, essentially, a closed surface-water basin although a small part of the valley at the southwestern end drains into the adjacent Cedar Valley. Groundwater occurs in and has been developed mainly from the unconsolidated basin-fill aquifer. Long-term downward trends in groundwater levels have been documented by the U.S. Geological Survey (USGS) since the mid-1950s. The water resources of Parowan Valley were assessed during 2012 to 2014 with an emphasis on refining the understanding of the groundwater and surface-water systems and updating the groundwater budget.Surface-water discharge of five perennial mountain streams that enter Parowan Valley was measured from 2013 to 2014. The total annual surface-water discharge of the five streams during 2013 to 2014 was about 18,000 acre-feet (acre-ft) compared to the average annual streamflow of about 22,000 acre-ft from USGS streamgages operated on the three largest of these streams from the 1940s to the 1980s. The largest stream, Parowan Creek, contributes more than 50 percent of the annual surface-water discharge to the valley, with smaller amounts contributed by Red, Summit, Little, and Cottonwood Creeks.Average annual recharge to the Parowan Valley groundwater system was estimated to be about 25,000 acre-ft from 1994 to 2013. Nearly all recharge occurs as direct infiltration of snowmelt and rainfall on the Markagunt Plateau east of the valley. Smaller amounts of recharge occur as infiltration of streamflow and unconsumed irrigation water near the east side of the valley on alluvial fans associated with mountain streams at the foot of the Red Cliffs. Subsurface flow from the mountain block to the east of the valley is a significant source of groundwater recharge to the basin-fill aquifer

Nuclear power and the Hamilton-Jefferson debate

International Nuclear Information System (INIS)

Hacker, A.

1980-01-01

The basic sources of nuclear opposition derive from the philosophical arguments of Thomas Jefferson against Alexander Hamilton's vision of an industrial society with a strong central authority. Today's young people continue Jefferson's radical plea for the individual freedoms associated with personal ownership and limited government, but they accept the structure of the former while searching for the romanticism of the latter. The nuclear debate reflects this dichotomy and will continue even if the issues of waste disposal and safety are resolved

An optimal L1-minimization algorithm for stationary Hamilton-Jacobi equations

KAUST Repository

Guermond, Jean-Luc; Popov, Bojan

2009-01-01

We describe an algorithm for solving steady one-dimensional convex-like Hamilton-Jacobi equations using a L1-minimization technique on piecewise linear approximations. For a large class of convex Hamiltonians, the algorithm is proven

New Li-Yau-Hamilton Inequalities for the Ricci Flow via the Space-Time Approach

OpenAIRE

Chow, Bennett; Knopf, Dan

2002-01-01

We generalize Hamilton's matrix Li-Yau-type Harnack estimate for the Ricci flow by considering the space of all LYH (Li-Yau-Hamilton) quadratics that arise as curvature tensors of space-time connections satisfying the Ricci flow with respect to the natural space-time degenerate metric. As a special case, we employ scaling arguments to derive a linear-type matrix LYH estimate. The new LYH quadratics obtained in this way are associated to the system of the Ricci flow coupled to a 1-form and a 2...

Uptake and release of 99mTc-CPI in cultured myocardial cells

International Nuclear Information System (INIS)

Li Shengting; Xiao Yanling; Yu Qifu; Zhang Hongyuan; Tang Jingrong

1991-01-01

The uptake and release of 99m Tc-CPI were studied in cultured monolayer neonatal rat myocardial cells incubated under normal condition (37 deg C, pH 7.4). The plateau level of uptake (4291.6 cpm/mg cell protein) was reached at 41.4 min when incubated with 37 kBq 99m Tc-CPI. The 99m Tc-CPI release was composed of at least two components. The fast component had a half-time (t 1/2 ) of 3.3 min and the slow one 198.0 min. It was suggested by the authors that the uptake of 99m Tc-CPI by cultured myocardial cells might be related to passive diffusion

A semi-automatic method for peak and valley detection in free-breathing respiratory waveforms

International Nuclear Information System (INIS)

Lu Wei; Nystrom, Michelle M.; Parikh, Parag J.; Fooshee, David R.; Hubenschmidt, James P.; Bradley, Jeffrey D.; Low, Daniel A.

2006-01-01

The existing commercial software often inadequately determines respiratory peaks for patients in respiration correlated computed tomography. A semi-automatic method was developed for peak and valley detection in free-breathing respiratory waveforms. First the waveform is separated into breath cycles by identifying intercepts of a moving average curve with the inspiration and expiration branches of the waveform. Peaks and valleys were then defined, respectively, as the maximum and minimum between pairs of alternating inspiration and expiration intercepts. Finally, automatic corrections and manual user interventions were employed. On average for each of the 20 patients, 99% of 307 peaks and valleys were automatically detected in 2.8 s. This method was robust for bellows waveforms with large variations

Nuclear power and the Hamilton-Jefferson debate

Energy Technology Data Exchange (ETDEWEB)

Hacker, A.

The basic sources of nuclear opposition derive from the philosophical arguments of Thomas Jefferson against Alexander Hamilton's vision of an industrial society with a strong central authority. Today's young people continue Jefferson's radical plea for the individual freedoms associated with personal ownership and limited government, but they accept the structure of the former while searching for the romanticism of the latter. The nuclear debate reflects this dichotomy and will continue even if the issues of waste disposal and safety are resolved. (DCK)

Lax-Friedrichs sweeping scheme for static Hamilton-Jacobi equations

International Nuclear Information System (INIS)

Kao, C.Y.; Osher, Stanley; Qian Jianliang

2004-01-01

We propose a simple, fast sweeping method based on the Lax-Friedrichs monotone numerical Hamiltonian to approximate viscosity solutions of arbitrary static Hamilton-Jacobi equations in any number of spatial dimensions. By using the Lax-Friedrichs numerical Hamiltonian, we can easily obtain the solution at a specific grid point in terms of its neighbors, so that a Gauss-Seidel type nonlinear iterative method can be utilized. Furthermore, by incorporating a group-wise causality principle into the Gauss-Seidel iteration by following a finite group of characteristics, we have an easy-to-implement, sweeping-type, and fast convergent numerical method. However, unlike other methods based on the Godunov numerical Hamiltonian, some computational boundary conditions are needed in the implementation. We give a simple recipe which enforces a version of discrete min-max principle. Some convergence analysis is done for the one-dimensional eikonal equation. Extensive 2-D and 3-D numerical examples illustrate the efficiency and accuracy of the new approach. To our knowledge, this is the first fast numerical method based on discretizing the Hamilton-Jacobi equation directly without assuming convexity and/or homogeneity of the Hamiltonian

Lax-Friedrichs sweeping scheme for static Hamilton-Jacobi equations

Science.gov (United States)

Kao, Chiu Yen; Osher, Stanley; Qian, Jianliang

2004-05-01

We propose a simple, fast sweeping method based on the Lax-Friedrichs monotone numerical Hamiltonian to approximate viscosity solutions of arbitrary static Hamilton-Jacobi equations in any number of spatial dimensions. By using the Lax-Friedrichs numerical Hamiltonian, we can easily obtain the solution at a specific grid point in terms of its neighbors, so that a Gauss-Seidel type nonlinear iterative method can be utilized. Furthermore, by incorporating a group-wise causality principle into the Gauss-Seidel iteration by following a finite group of characteristics, we have an easy-to-implement, sweeping-type, and fast convergent numerical method. However, unlike other methods based on the Godunov numerical Hamiltonian, some computational boundary conditions are needed in the implementation. We give a simple recipe which enforces a version of discrete min-max principle. Some convergence analysis is done for the one-dimensional eikonal equation. Extensive 2-D and 3-D numerical examples illustrate the efficiency and accuracy of the new approach. To our knowledge, this is the first fast numerical method based on discretizing the Hamilton-Jacobi equation directly without assuming convexity and/or homogeneity of the Hamiltonian.

Hamilton-Jacobi equation and the breaking of the WKB approximation

Energy Technology Data Exchange (ETDEWEB)

Canfora, F. [Istituto Nazionale di Fisica Nucleare, GC di Salerno (Italy) and Dipartimento di Fisica E.R. Caianiello, Universita di Salerno, Via S. Allende, 84081 Baronissi (Salerno) (Italy)]. E-mail: canfora@sa.infn.it

2005-03-17

A simple method to deal with four-dimensional Hamilton-Jacobi equation for null hypersurfaces is introduced. This method allows to find simple geometrical conditions which give rise to the failure of the WKB approximation on curved spacetimes. The relation between such failure, extreme blackholes and the Cosmic Censor hypothesis is briefly discussed.

Hamilton-Jacobi formalism for Podolsky's electromagnetic theory on the null-plane

Science.gov (United States)

Bertin, M. C.; Pimentel, B. M.; Valcárcel, C. E.; Zambrano, G. E. R.

2017-08-01

We develop the Hamilton-Jacobi formalism for Podolsky's electromagnetic theory on the null-plane. The main goal is to build the complete set of Hamiltonian generators of the system as well as to study the canonical and gauge transformations of the theory.

Derivation of the Schrodinger Equation from the Hamilton-Jacobi Equation in Feynman's Path Integral Formulation of Quantum Mechanics

Science.gov (United States)

Field, J. H.

2011-01-01

It is shown how the time-dependent Schrodinger equation may be simply derived from the dynamical postulate of Feynman's path integral formulation of quantum mechanics and the Hamilton-Jacobi equation of classical mechanics. Schrodinger's own published derivations of quantum wave equations, the first of which was also based on the Hamilton-Jacobi…

Sediment erosion and delivery from Toutle River basin after the 1980 eruption of Mount St. Helens: A 30-year perspective

Science.gov (United States)

Major, Jon J.; Mosbrucker, Adam; Spicer, Kurt R.; Crisafulli, Charles; Dale, V.

2018-01-01

Exceptional sediment yields persist in Toutle River valley more than 30 years after the major 1980 eruption of Mount St. Helens. Differencing of decadal-scale digital elevation models shows the elevated load comes largely from persistent lateral channel erosion across the debris-avalanche deposit. Since the mid-1980s, rates of channel-bed-elevation change have diminished, and magnitudes of lateral erosion have outpaced those of channel incision. A digital elevation model of difference from 1999 to 2009 shows erosion across the debris-avalanche deposit is more spatially distributed compared to a model from 1987 to 1999, in which erosion was strongly focused along specific reaches of the channel.

Light Rail Transit in Hamilton: Health, Environmental and Economic Impact Analysis

Science.gov (United States)

Topalovic, P.; Carter, J.; Topalovic, M.; Krantzberg, G.

2012-01-01

Hamilton's historical roots as an electric, industrial and transportation-oriented city provide it with a high potential for rapid transit, especially when combined with its growing population, developing economy, redeveloping downtown core and its plans for sustainable growth. This paper explores the health, environmental, social and economic…

Chaos M-ary modulation and demodulation method based on Hamilton oscillator and its application in communication.

Science.gov (United States)

Fu, Yongqing; Li, Xingyuan; Li, Yanan; Yang, Wei; Song, Hailiang

2013-03-01

Chaotic communication has aroused general interests in recent years, but its communication effect is not ideal with the restriction of chaos synchronization. In this paper a new chaos M-ary digital modulation and demodulation method is proposed. By using region controllable characteristics of spatiotemporal chaos Hamilton map in phase plane and chaos unique characteristic, which is sensitive to initial value, zone mapping method is proposed. It establishes the map relationship between M-ary digital information and the region of Hamilton map phase plane, thus the M-ary information chaos modulation is realized. In addition, zone partition demodulation method is proposed based on the structure characteristic of Hamilton modulated information, which separates M-ary information from phase trajectory of chaotic Hamilton map, and the theory analysis of zone partition demodulator's boundary range is given. Finally, the communication system based on the two methods is constructed on the personal computer. The simulation shows that in high speed transmission communications and with no chaos synchronization circumstance, the proposed chaotic M-ary modulation and demodulation method has outperformed some conventional M-ary modulation methods, such as quadrature phase shift keying and M-ary pulse amplitude modulation in bit error rate. Besides, it has performance improvement in bandwidth efficiency, transmission efficiency and anti-noise performance, and the system complexity is low and chaos signal is easy to generate.

Israeli Infotech Migrants in Silicon Valley

Directory of Open Access Journals (Sweden)

Steven J. Gold

2018-01-01

Full Text Available Prior to the 1980s, Israel’s national ideology discouraged emigration and entrepreneurship among its citizens. Yet, by the late 1990s, Israeli emigrants were one of the leading immigrant nationalities in Silicon Valley. Drawing on interviews, fieldwork, a literature review, and perusal of social media, I explore the origins of Israeli involvement in high-tech activities and the extensive linkages between Israeli emigrants and the Israeli high-tech industry. I also summarize the patterns of communal cooperation that permit emigrant families to maintain an Israel-oriented way of life in suburban communities south of San Francisco, and I compare these patterns with those of Indians, a nationality engaged in the same pursuit. I conclude by considering the impact of infotech involvement on Israeli immigrants and on the U.S. economy.

Update on the status of the West Valley demonstration project

International Nuclear Information System (INIS)

Greeves, J.T.; Camper, L.W.; Orlando, D.A.; Glenn, C.J.; Buckley, J.T.; Giardina, P.A.

2002-01-01

From 1966 to 1972, under an Atomic Energy Commission (AEC) license, Nuclear Fuel Services (NFS) reprocessed 640 metric tons of spent fuel at its West Valley, New York, facility-, the only commercial spent fuel reprocessing plant in the U.S. The facility shut down in 1972, for modifications to increase its seismic stability and to expand its capacity. In 1976, without restarting the operation, NFS withdrew from the reprocessing business and returned control of the facilities to the site owner, the New York State Energy Research and Development Authority (NYSERDA). The reprocessing activities resulted in about 2.3 million liters (600,000 gallons) of liquid high-level waste (HLW) stored below ground in tanks, other radioactive wastes, and residual radioactive contamination. The West Valley site was licensed by AEC, and then the U.S. Nuclear Regulatory Commission (NRC), until 1981, when the license was suspended to execute the 1980 West Valley Demonstration Project (WVDP) Act. The WVDP Act outlines the responsibilities of the U.S. Department of Energy (DOE), NRC, and NYSERDA at the site, including the NRC's responsibility to develop decommissioning criteria for the site. The Commission published the final policy statement on decommissioning criteria for the WVDP at the West Valley site after considering comments from interested stakeholders. In that regard, the Commission prescribed the License Termination Rule (LTR) criteria for the WVDP at the West Valley site, reflecting the fact that the applicable decommissioning goal for the entire NRC-licensed site is compliance with the requirements of the LTR. This paper will describe the history of the site, provide an update of the status of the decommissioning of the site and an overview of the technical and policy issues facing Federal and State regulators and other stakeholders as they strive to complete the remediation of the site. (author)

Perceptions of Quality Life in Hamilton's Neighbourhood Hubs: A Qualitative Analysis

Science.gov (United States)

Eby, Jeanette; Kitchen, Peter; Williams, Allison

2012-01-01

This paper examines perceptions of quality of life in Hamilton, Ontario, Canada from the perspective of residents and key community stakeholders. A series of eight focus groups were conducted. Six sessions were held with residents of neighbourhood "hubs", areas characterized by high levels of poverty. The following themes were…

Air Quality in Hamilton: Who Is Concerned? Perceptions from Three Neighbourhoods

Science.gov (United States)

Simone, Dylan; Eyles, John; Newbold, K. Bruce; Kitchen, Peter; Williams, Allison

2012-01-01

This study investigates the factors influencing perceptions of air quality in the industrial city of Hamilton, Canada. The research employs data collected via a telephone survey of 1,002 adult residents in three neighbourhoods. Perceptions in the neighbourhoods were examined by individual socio-demographic factors (age, gender, marital and…

Radiation dose to bladder wall following the administration of sup(99m)Tc-microspheres and sup(99m)Tc-DTPA

International Nuclear Information System (INIS)

Smith, T.

1981-01-01

Castronovo et al. (Health Phys. Vol. 39, p 112, 1980) reported a method of calculating the dose to the bladder wall following administration of sup(99m)Tc human albumin microspheres (sup(99m)Tc-HAM) for lung perfusion scanning. The present note comments that (1) the dosimetry is estimated for an unusual bladder voiding schedule and no indication is given of the variation of dose to be expected with different schedules, and (2) that the method assumes linear biological excretion of the radiopharmaceutical into the bladder in any particular filling period. It is shown that whilst this is a valid approximation in the case considered, it is not a generally applicable principle. Values of bladder wall dose commitments following intravenous administration of sup(99m)Tc-HAM or sup(99m)Tc DTPA are tabulated. Values for constant voiding cycles are presented for four different bladder voiding periods between 2 and 8 hr, and for three different methods of calculation:-a method described in this paper, the linear excretion method of Castronovo et al., and the method of Snyder et al. (ORNL-4584, pp. 206-208, 1970) which allows for urine flow rate. (U.K.)

Safety evaluation report related to operation of Sequoyah Nuclear Plant, Units 1 and 2, Docket nos. 50-327 and 50-328, Tennessee Valley Authority

Energy Technology Data Exchange (ETDEWEB)

NONE

1979-03-01

A safety evaluation of the Tennessee Valley Authority's application for a license to operate its Sequoyah Nuclear Plant, Units 1 and 2, located in Hamilton County, Tennessee, has been prepared by the Office of Nuclear Reactor Regulation of the Nuclear Regulatory Commission. It consists of a technical review and staff evaluation of applicant information on: (1) population density, land use, and physical characteristics of the site area; (2) design, fabrication, construction, testing criteria, and performance characteristics of plant structures, systems, and components important to safety; (3) expected response of the facility to anticipated operating transients, and to postulated design basis accidents; (4) applicant engineering and construction organization, and plans for the conduct of plant operations; and (5) design criteria for a system to control the plant's radiological effluents. The staff has concluded that the plant can be operated by the Tennessee Valley Authority without endangering the health and safety of the public provided that the outstanding matters discussed in the report are favorably resolved. (author)

Hamilton-Jacobi formalism to warm inflationary scenario

Science.gov (United States)

Sayar, K.; Mohammadi, A.; Akhtari, L.; Saaidi, Kh.

2017-01-01

The Hamilton-Jacobi formalism as a powerful method is being utilized to reconsider the warm inflationary scenario, where the scalar field as the main component driving inflation interacts with other fields. Separating the context into strong and weak dissipative regimes, the goal is followed for two popular functions of Γ . Applying slow-rolling approximation, the required perturbation parameters are extracted and, by comparing to the latest Planck data, the free parameters are restricted. The possibility of producing an acceptable inflation is studied where the result shows that for all cases the model could successfully suggest the amplitude of scalar perturbation, scalar spectral index, its running, and the tensor-to-scalar ratio.

Use of a three-dimensional model for the analysis of the ground-water flow system in Parker Valley, Arizona and California

Science.gov (United States)

Tucci, Patrick

1982-01-01

A three-dimensional, finite-difference model was used to simulate ground-water flow conditions in Parker Valley. The study evaluated present knowledge and concepts of the ground-water system and the ability of the model to represent the system. Modeling assumptions and generalized physical parameters that were used may have transfer value in the construction and calibration of models of other basins along the lower Colorado River. The aquifer was simulated in two layers to represent the three-dimensional system. Ground-water conditions were simulated for 1940-41, the mid-1960's, and 1980. Overall model results generally compared favorably with available field information. The model results showed that for 1940-41 the Colorado River was a losing stream through out Parker Valley. Infiltration of surface water from the river was the major source of recharge. The dominant mechanism of discharge was evapotranspiration by phreatophytes. Agricultural development between 1941 and the mid-1960 's resulted in significant changes to the ground-water system. Model results for conditions in the mid-1960 's showed that the Colorado River had become a gaining stream in the northern part of the valley as a result of higher water levels. The rise in water levels was caused by infiltration of applied irrigation water. Diminished water-level gradients from the river in the rest of the valley reduced the amount of infiltration of surface water from the river. Models results for conditions in 1980 showed that ground-water level rises of several feet caused further reduction in the amount of surface-water infiltration from the river. (USGS)

Hamilton and Hardy for the 21st Century

Science.gov (United States)

Ogden, Trevor

2016-01-01

Hamilton and Hardy’s Industrial Toxicology is now 80 years old, and the new sixth edition links us with a pioneer era. This is an impressive book, but the usefulness of the hardback version as a reference book is unfortunately limited by its poor index. There is now an ebook version, and for the practitioner on the move this has the great advantages of searchability and portability. However, Wiley ebooks can apparently only be downloaded when first purchased, so their lifetime is limited to that of the device. The Kindle edition should avoid this shortcoming.

Octavia Butler and Virginia Hamilton: Black Women Writers and Science Fiction.

Science.gov (United States)

Hampton, Gregory Jerome; Brooks, Wanda M.

2003-01-01

Notes that African American literature has always had science fiction elements in its focus on narratives of the alienated and marginalized "other." Contends that Octavia Butler and Virginia Hamilton are two African American writers of science fiction who examine the connections between the stories of a culture and the genre of science…

Generalized anxiety disorder and the Hamilton Anxiety Rating Scale in Parkinson's disease Transtorno de ansiedade generalizada e a Escala de Ansiedade de Hamilton na doença de Parkinson

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Arthur Kummer

2010-08-01

Full Text Available Anxiety is common in Parkinson's disease (PD, but studies concerning specific anxiety disorders are scarce. Essential psychometric properties of anxiety rating scales are also lacking. OBJECTIVE: To investigate general anxiety disorder (GAD in PD and psychometric properties of the Hamilton Anxiety Rating Scale (Ham-A. METHOD: Ninety-one PD patients underwent neurological and psychiatric examination, which included the MINI-Plus, the Ham-A and the Hamilton Depression Rating Scale (Ham-D. RESULTS: GAD was present in 30.8% of PD patients. Patients with GAD had longer disease duration (p=0.044 and were in use of higher doses of levodopa (p=0.034. They also tended to have more motor fluctuations and dyskinesias. The group with GAD scored higher in Ham-A (pAnsiedade é comum na doença de Parkinson (DP, mas estudos sobre transtornos de ansiedade específicos são ainda escassos. Faltam também estudos sobre propriedades psicométricas essenciais das escalas de ansiedade. OBJETIVO: Investigar o transtorno de ansiedade generalizada (TAG na DP e propriedades psicométricas da Escala de Ansiedade de Hamilton (Ham-A. MÉTODO: Noventa e um pacientes com DP se submeteram a exames neurológico e psiquiátrico, que incluiu o MINI-Plus, a Ham-A e a Escala de Depressão de Hamilton (Ham-D. RESULTADOS: TAG esteve presente em 30,8% dos participantes. Pacientes com TAG tinham maior duração de doença (p=0,044 e estavam em uso de maiores doses de levodopa (p=0,034. Também havia uma tendência desses pacientes terem mais flutuações motoras e discinesias. O grupo com TAG pontuou mais alto na Ham-A (p<0,001, nas subescalas somática (p<0,001 e psíquica da Ham-A (p<0,001, e na Ham-D (p=0,004. A Ham-A mostrou boa consistência interna (alfa de Cronbach=0,893 e um ponto de corte de 10/11 é sugerido para triar o TAG. CONCLUSÃO: TAG é freqüente na DP e a Ham-A pode ser um instrumento útil para triar esse transtorno.

Expanded social fitness and Hamilton's rule for kin, kith, and kind.

Science.gov (United States)

Queller, David C

2011-06-28

Inclusive fitness theory has a combination of simplicity, generality, and accuracy that has made it an extremely successful way of thinking about and modeling effects on kin. However, there are types of social interactions that, although covered, are not illuminated. Here, I expand the inclusive fitness approach and the corresponding neighbor-modulated approach to specify two other kinds of social selection. Kind selection, which includes greenbeards and many nonadditive games, is where selection depends on an actor's trait having different effects on others depending on whether they share the trait. Kith selection includes social effects that do not require either kin or kind, such as mutualism and manipulation. It involves social effects of a trait that affect a partner, with feedback to the actor's fitness. I derive expanded versions of Hamilton's rule for kith and kind selection, generalizing Hamilton's insight that we can model social selection through a sum of fitness effects, each multiplied by an appropriate association coefficient. Kinship is, thus, only one of the important types of association, but all can be incorporated within an expanded inclusive fitness.

Ecological structuring of yeasts associated with trees around Hamilton, Ontario, Canada.

Science.gov (United States)

Maganti, Harinad; Bartfai, David; Xu, Jianping

2012-02-01

This study seeks to determine the distribution and diversity of yeasts in and around the Hamilton area in Canada. In light of the increasing number of fungal infections along with rising morbidity and mortality rates, especially among the immunocompromised, understanding the diversity and distribution of yeasts in natural environments close to human habitations has become an increasingly relevant topic. In this study, we analyzed 1110 samples obtained from the hollows of trees, shrubs and avian droppings at 8 geographical sites in and around Hamilton, Ontario, Canada. A total of 88 positive yeast strains were isolated and identified belonging to 20 yeast species. Despite the relative proximity of the sampling sites, our DNA fingerprinting results showed that the yeast populations were highly heterogenous. Among the 14 tree species sampled, cedar, cottonwood and basswood hollows had relatively high yeast colonization rates. Interestingly, Candida parapsilosis was isolated almost exclusively from Pine trees only. Our results are consistent with microgeographic and ecological differentiation of yeast species in and around an urban environment. © 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

A conceptual model for site-level ecology of the giant gartersnake (Thamnophis gigas) in the Sacramento Valley, California

Science.gov (United States)

Halstead, Brian J.; Wylie, Glenn D.; Casazza, Michael L.; Hansen, Eric C.; Scherer, Rick D.; Patterson, Laura C.

2015-08-14

Giant gartersnakes (Thamnophis gigas) comprise a species of semi-aquatic snakes precinctive to marshes in the Central Valley of California (Hansen and Brode, 1980; Rossman and others, 1996). Because more than 90 percent of their historical wetland habitat has been converted to other uses (Frayer and others, 1989; Garone, 2007), giant gartersnakes have been listed as threatened by the State of California (California Department of Fish and Game Commission , 1971) and the United States (U.S. Fish and Wildlife Service, 1993). Giant gartersnakes currently occur in a highly modified landscape, with most extant populations occurring in the rice - growing regions of the Sacramento Valley, especially near areas that historically were tule marsh habitat (Halstead and others, 2010, 2014).

Profiles of the Caribbean Basin in 1960/1980: Changing Geopolitical and Geostrategic Dimensions.

Science.gov (United States)

1983-12-01

8.816.000 (SI = I quetzal ) ARM1Y: 8,400 regs 2 bns 18 60mm (US). 99 80mm (Ger), 8 81mm (US), 2 lnchr (flare) mor; 17 3. 5 -in rkt lnchr (US), 8 57mm rclss...service: conscription; 2 years Total armed forces: 15,050 Estimated GNP 1979: S6.9 bn Defense excpenditure 1980: 76.8 m quetzal ’S69.S m) S51 1.1 quetzal ...1980), 1.0 quetzal (1979) ARMY: 14,000 4 bde H{Q 1 Presidential Guard bde 9 jnf bps 1 Para bn 1 engr bn I armd car co 13 arty btys 7 M-3 Sruart It tks

Utilization of the NFS West Valley Installation for spent fuel storage

International Nuclear Information System (INIS)

MacDonald, R.W.

1978-04-01

Several thousand MT of capacity of AFR storage will be required in the 1980's. The pool at NFS has capacity for an additional 60 MT of BWR fuel or 150 MT of PWR assemblies. Zircaloy-clad LWR fuel can be stored in pools for up to 100 years. Environmental effects are discussed. Expansion of the pool capacity for as much as 1000 MT more, either by using more compact storage racks or constructing a new pool or an independent pool, is considered. Some indication of the environmental impacts of expanded fuel storage capacity at West Valley is offered by experience at Barnwell

An overview of waste management systems at the West Valley demonstration project

International Nuclear Information System (INIS)

McIntosh, T.W.; Bixby, W.W.; Krauss, J.E.; Leap, D.R.

1988-01-01

In 1980, the United States Congress passed into law the West Valley Demonstration Project Act authorizing the Department of Energy (DOE) to conduct a nuclear waste management project at a former commercial nuclear fuel reprocessing facility located in West Valley, New York. The Project's main objective is to solidify approximately two million litres of high-level radioactive liquid waste into a form suitable for transport to a federal repository for final disposal. The majority of the liquid waste was produced as a by-product of the PUREX extraction process and is stored in an underground steel tank. A waste characterization program has shown that the neutralized waste has settled into two distinct layers: a clear alkaline liquid (supernatant) layer and a dense precipitate (sludge) layer. The principle radioactive elements in the waste are cesium 137 (supernatant) and strontium 90 (sludge). This paper describes the overall project strategy, the waste management systems, the present project engineering and construction status and the project schedule leading to radioactive operation

Hamilton y el Descubrimiento de los Cuaterniones

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José Manuel Sánchez Muñoz

2011-10-01

Full Text Available Este artículo pretende ofrecer una visión general del descubrimiento de los llamados cuaterniones por parte del matemático irlandés William Rowan Hamilton. Se pretende dar al lector algunos detalles del nacimiento de los números imaginarios en el siglo XVI, su interpretación geométrica a principios del siglo XIX, y la extensión del plano complejo a las tres dimensiones a través de los cuaterniones, que abrirían el paso al estudio y el desarrollo de las nuevas álgebras no conmutativas y a una nueva interpretación tridimensional de la realidad física.

Valley-dependent band structure and valley polarization in periodically modulated graphene

Science.gov (United States)

Lu, Wei-Tao

2016-08-01

The valley-dependent energy band and transport property of graphene under a periodic magnetic-strained field are studied, where the time-reversal symmetry is broken and the valley degeneracy is lifted. The considered superlattice is composed of two different barriers, providing more degrees of freedom for engineering the electronic structure. The electrons near the K and K' valleys are dominated by different effective superlattices. It is found that the energy bands for both valleys are symmetric with respect to ky=-(AM+ξ AS) /4 under the symmetric superlattices. More finite-energy Dirac points, more prominent collimation behavior, and new crossing points are found for K' valley. The degenerate miniband near the K valley splits into two subminibands and produces a new band gap under the asymmetric superlattices. The velocity for the K' valley is greatly renormalized compared with the K valley, and so we can achieve a finite velocity for the K valley while the velocity for the K' valley is zero. Especially, the miniband and band gap could be manipulated independently, leading to an increase of the conductance. The characteristics of the band structure are reflected in the transmission spectra. The Dirac points and the crossing points appear as pronounced peaks in transmission. A remarkable valley polarization is obtained which is robust to the disorder and can be controlled by the strain, the period, and the voltage.

The regulation of technetium-99 discharges at Sellafield

International Nuclear Information System (INIS)

Mayall, A.

2002-01-01

The reprocessing of spent Magnox fuel at BNFL Sellafield produces a liquid waste concentrate containing technetium-99 and other, more radiotoxic, radionuclides such as plutonium and americium. The concentrate is known as medium active concentrate (MAC). Prior to 1981, MAC was discharged to sea untreated after several years' storage, during which short-lived radionuclides underwent radioactive decay. In the early 1980s, discharges of MAC were suspended and it was retained in storage tanks, pending the construction of a plant to remove the radionuclides of greatest radiological concern (these did not include technetium- 99). The Enhanced Actinide Removal Plant started operation in 1994 and began to clear the backlog of stored waste MAC, as well as current arisings from Magnox reprocessing. As a consequence technetium-99 was once more discharged to sea. Subsequently, concentrations of this radionuclide in the marine environment increased. In particular, there was a significant increase in the concentration of technetium-99 in lobster in the Irish Sea. An increase in technetium-99 has also been detected at locations far distant from Sellafield, e.g. in Scandinavian coastal waters, albeit at very low concentrations. This dispersal of technetium- 99 throughout the Irish Sea and further afield has therefore caused concern, although the radiological impact is low. This paper examines the nature and source of the technetium-99 in sea discharges at Sellafield and the levels of past and current discharges as well as their impact. It goes on to describe the Environment Agency's recent proposals on the future regulation of technetium-99 discharges and how these should lead to substantial reductions in not only technetium-99 discharges, but also of other radionuclides such as caesium-137 and strontium-90. (author)

Periodic solutions of the Hamilton-Jacobi equation by the shooting method: A technique for beam dynamics

International Nuclear Information System (INIS)

Gabella, W.E.; Ruth, R.D.; Warnock, R.L.

1988-05-01

Periodic solutions of the Hamilton-Jacobi equation determine invariant tori in phase space. The Fourier spectrum of a torus with respect to angular coordinates gives useful information about nonlinear resonances and their potential for causing instabilities. We describe a method to solve the Hamilton-Jacobi equation for an arbitrary accelerator lattice. The method works with Fourier modes of the generating functions, and imposes periodicity in the machine azimuth by a shooting method. We give examples leading to three-dimensional plots in a surface of section. It is expected that the technique will be useful in lattice optimization. 14 refs., 6 figs., 1 tab

76 FR 25534 - Airworthiness Directives; Hamilton Sundstrand Propellers Model 247F Propellers

Science.gov (United States)

2011-05-05

... 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this AD, the... through FR2279 inclusive, FR 2398, FR2449 to FR2958 inclusive, FR20010710 to FR20010722 inclusive, and FR20010723RT to FR20020127RT inclusive, installed. Propeller blades reworked to Hamilton Sundstrand Service...

An optimal L1-minimization algorithm for stationary Hamilton-Jacobi equations

KAUST Repository

Guermond, Jean-Luc

2009-01-01

We describe an algorithm for solving steady one-dimensional convex-like Hamilton-Jacobi equations using a L1-minimization technique on piecewise linear approximations. For a large class of convex Hamiltonians, the algorithm is proven to be convergent and of optimal complexity whenever the viscosity solution is q-semiconcave. Numerical results are presented to illustrate the performance of the method.

Potential impact on water resources from future volcanic eruptions at Long Valley, Mono County, California, U.S.A

International Nuclear Information System (INIS)

Hopson, R.F.

1991-01-01

Earthquakes, ground deformation, and increased geothermal activity at Long Valley caldera after mid-1980 suggest the possibility of a volcanic eruption in the near future. An eruption there could have serious consequences for the City of Los Angeles, depending on the magnitude and volume of materials ejected because surface water in Mono Basin plus surface and groundwater in Owens Valley accounts for about 80% of its water supply. Eruptions of moderate to very large magnitude could impede the supply of water from this area for several days, weeks, or even years by discharging small to large volumes of volcanic ash and causing lahars. Soon after an eruption, water quality would likely be affected by the accumulation of organic debris and microorganisms in surface waters

Viscous warm inflation: Hamilton-Jacobi formalism

Science.gov (United States)

Akhtari, L.; Mohammadi, A.; Sayar, K.; Saaidi, Kh.

2017-04-01

Using Hamilton-Jacobi formalism, the scenario of warm inflation with viscous pressure is considered. The formalism gives a way of computing the slow-rolling parameter without extra approximation, and it is well-known as a powerful method in cold inflation. The model is studied in detail for three different cases of the dissipation and bulk viscous pressure coefficients. In the first case where both coefficients are taken as constant, it is shown that the case could not portray warm inflationary scenario compatible with observational data even it is possible to restrict the model parameters. For other cases, the results shows that the model could properly predicts the perturbation parameters in which they stay in perfect agreement with Planck data. As a further argument, r -ns and αs -ns are drown that show the acquired result could stand in acceptable area expressing a compatibility with observational data.

Perturbation to Unified Symmetry and Adiabatic Invariants for Relativistic Hamilton Systems

International Nuclear Information System (INIS)

Zhang Mingjiang; Fang Jianhui; Lu Kai; Pang Ting; Lin Peng

2009-01-01

Based on the concept of adiabatic invariant, the perturbation to unified symmetry and adiabatic invariants for relativistic Hamilton systems are studied. The definition of the perturbation to unified symmetry for the system is presented, and the criterion of the perturbation to unified symmetry is given. Meanwhile, the Noether adiabatic invariants, the generalized Hojman adiabatic invariants, and the Mei adiabatic invariants for the perturbed system are obtained. (general)

Changing Relations between High Castes and Tamang in Melamchi Valley

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Binod Pokharel

2011-04-01

Full Text Available This paper is about the processes of transformation of social relations between high caste groups and Tamang in Melamchi Valley for the period of 1980-2010. Development interventions made by government of Nepal and (I NGOs, a decade long undergoing Melamchi Water Supply Project and labor migration are major factors for ongoing changes in the study area. Spread of literacy classes and primary education, availability of credit institutions, introduction of modern farming, road networks, seasonal out migration from the area, etc. primarily define new relations among the groups. Borrowing and lending money were one of the basis of high caste and Tamang relation in past. The latter was regarded as borrower loan from first one. Before 1980s, money and agriculture commodities were controlled by few rich and high castes people. Cash income from various sources made enable the Tamang to stand on an equal footing with high caste people. Open political economy and liberal policy for issuing pass port in 1990s and after that encourage the people to diversify the destination of seasonal migration from India to Gulf countries and East Asia. Various processes of socio-economic and political changes led to local peoples to seek their position and identity in the changing context. Discourse of Tamang, high castes and Dalit entered into the Valley along with the development resources of (INGO and political movements of the country. This made possible to Tamang and other disadvantage groups to define and redefine their ethnic identity. Keywords: High castes; Tamang; credit facilities; subsistence farming; identity construction; money lending; wage labor DOI: 10.3126/dsaj.v4i0.4513 Dhaulagiri Journal of Sociology and Anthropology Vol.4 2010 pp.65-84

Variational energy principle for compressible, baroclinic flow. 2: Free-energy form of Hamilton's principle

Science.gov (United States)

Schmid, L. A.

1977-01-01

The first and second variations are calculated for the irreducible form of Hamilton's Principle that involves the minimum number of dependent variables necessary to describe the kinetmatics and thermodynamics of inviscid, compressible, baroclinic flow in a specified gravitational field. The form of the second variation shows that, in the neighborhood of a stationary point that corresponds to physically stable flow, the action integral is a complex saddle surface in parameter space. There exists a form of Hamilton's Principle for which a direct solution of a flow problem is possible. This second form is related to the first by a Friedrichs transformation of the thermodynamic variables. This introduces an extra dependent variable, but the first and second variations are shown to have direct physical significance, namely they are equal to the free energy of fluctuations about the equilibrium flow that satisfies the equations of motion. If this equilibrium flow is physically stable, and if a very weak second order integral constraint on the correlation between the fluctuations of otherwise independent variables is satisfied, then the second variation of the action integral for this free energy form of Hamilton's Principle is positive-definite, so the action integral is a minimum, and can serve as the basis for a direct trail and error solution. The second order integral constraint states that the unavailable energy must be maximum at equilibrium, i.e. the fluctuations must be so correlated as to produce a second order decrease in the total unavailable energy.

Hamilton's inclusive fitness maintains heritable altruism polymorphism through rb = c.

Science.gov (United States)

Wang, Changcao; Lu, Xin

2018-02-20

How can altruism evolve or be maintained in a selfish world? Hamilton's rule shows that the former process will occur when rb > c -the benefits to the recipients of an altruistic act b , weighted by the relatedness between the social partners r , exceed the costs to the altruists c -drives altruistic genotypes spreading against nonaltruistic ones. From this rule, we infer that altruistic genotypes will persist in a population by forming a stable heritable polymorphism with nonaltruistic genotypes if rb = c makes inclusive fitness of the two morphs equal. We test this prediction using the data of 12 years of study on a cooperatively breeding bird, the Tibetan ground tit Pseudopodoces humilis , where helping is performed by males only and kin-directed. Individual variation in ever acting as a helper was heritable ( h 2 = 0.47), and the resultant altruism polymorphism remained stable as indicated by low-level annual fluctuation of the percentage of helpers among all adult males (24-28%). Helpers' indirect fitness gains from increased lifetime reproductive success of related breeders statistically fully compensated for their lifetime direct fitness losses, suggesting that rb = c holds. While our work provides a fundamental support for Hamilton's idea, it highlights the equivalent inclusive fitness returns to altruists and nonaltruists mediated by rb = c as a theoretically and realistically important mechanism to maintain social polymorphism.

Migration, Social Network, and Identity: The Evolution of Chinese Community in East San Gabriel Valley, 1980-2010

OpenAIRE

Hung, Yu-Ju

2013-01-01

American immigration reform, global economic rearrangement, and international migration inaugurated a new era of Chinese American immigration. The post-1960s immigration was characterized by various countries of origin, diverse socioeconomic backgrounds, and residential suburban settlements pattern. The San Gabriel Valley, a vast suburban area of Los Angeles County, is the representative of a new type of Chinese immigration community. Creating an ethnic community in Monterey Park in the 1970s...

Excellent reliability of the Hamilton Depression Rating Scale (HDRS-21) in Indonesia after training.

Science.gov (United States)

Istriana, Erita; Kurnia, Ade; Weijers, Annelies; Hidayat, Teddy; Pinxten, Lucas; de Jong, Cor; Schellekens, Arnt

2013-09-01

The Hamilton Depression Rating Scale (HDRS) is the most widely used depression rating scale worldwide. Reliability of HDRS has been reported mainly from Western countries. The current study tested the reliability of HDRS ratings among psychiatric residents in Indonesia, before and after HDRS training. The hypotheses were that: (i) prior to the training reliability of HDRS ratings is poor; and (ii) HDRS training can improve reliability of HDRS ratings to excellent levels. Furthermore, we explored cultural validity at item level. Videotaped HDRS interviews were rated by 30 psychiatric residents before and after 1 day of HDRS training. Based on a gold standard rating, percentage correct ratings and deviation from the standard were calculated. Correct ratings increased from 83% to 99% at item level and from 70% to 100% for the total rating. The average deviation from the gold standard rating improved from 0.07 to 0.02 at item level and from 2.97 to 0.46 for the total rating. HDRS assessment by psychiatric trainees in Indonesia without prior training is unreliable. A short, evidence-based HDRS training improves reliability to near perfect levels. The outlined training program could serve as a template for HDRS trainings. HDRS items that may be less valid for assessment of depression severity in Indonesia are discussed. Copyright © 2013 Wiley Publishing Asia Pty Ltd.

77 FR 33237 - Saline Valley Warm Springs Management Plan/Environmental Impact Statement, Death Valley National...

Science.gov (United States)

2012-06-05

... Valley Warm Springs Management Plan/Environmental Impact Statement, Death Valley National Park, Inyo... an Environmental Impact Statement for the Saline Valley Warm Springs Management Plan, Death Valley... analysis process for the Saline Valley Warm Springs Management Plan for Death Valley [[Page 33238...

Hamilton-Jacobi approach to non-slow-roll inflation

International Nuclear Information System (INIS)

Kinney, W.H.

1997-01-01

I describe a general approach to characterizing cosmological inflation outside the standard slow-roll approximation, based on the Hamilton-Jacobi formulation of scalar field dynamics. The basic idea is to view the equation of state of the scalar field matter as the fundamental dynamical variable, as opposed to the field value or the expansion rate. I discuss how to formulate the equations of motion for scalar and tensor fluctuations in situations where the assumption of slow roll is not valid. I apply the general results to the simple case of inflation from an open-quotes invertedclose quotes polynomial potential, and to the more complicated case of hybrid inflation. copyright 1997 The American Physical Society

L∞-error estimates of a finite element method for the Hamilton-Jacobi-Bellman equations

International Nuclear Information System (INIS)

Bouldbrachene, M.

1994-11-01

We study the finite element approximation for the solution of the Hamilton-Jacobi-Bellman equations involving a system of quasi-variational inequalities (QVI). We also give the optimal L ∞ -error estimates, using the concepts of subsolutions and discrete regularity. (author). 7 refs

A meta-analytic comparison of the Beck Depression Inventory and the Hamilton Rating Scale for Depression as measures of treatment outcome.

Science.gov (United States)

Edwards, B C; Lambert, M J; Moran, P W; McCully, T; Smith, K C; Ellingson, A G

1984-05-01

Some clinicians have considered the Beck Depression Inventory, a self-rating scale, too reactive to patient halo effects and, therefore, a liberal measure of treatment outcome. On the other hand, interviewer-rating scales, like the Hamilton Rating Scale for Depression have been viewed as more conservative measures of treatment gain. Studies which compared the Beck Depression Inventory to the Hamilton Rating Scale, as dependent measures, were reviewed for the purpose of determining if the scales provided comparable data for assessing treatment effects. The use of meta-analysis techniques resulted in a comparison of effect sizes which indicated that the Beck Depression Inventory was significantly less liberal than the Hamilton Rating Scale for Depression. The implications of these results for selecting outcome measures and the application of meta-analysis techniques for comparing dependent measures are discussed.

Respiratory Medicine at McMaster University, Hamilton, Ontario: 1968 to 2013

Directory of Open Access Journals (Sweden)

Norman L Jones

2014-01-01

Full Text Available The medical school at McMaster University (Hamilton, Ontario was conceived in 1965, and admitted the first class in 1969. John Evans became the founding Dean and he invited EJ Moran Campbell to be the first Chairman of the Department of Medicine. Moran Campbell, already a world figure in respiratory medicine and physiology, arrived at McMaster in September 1968, and he invited Norman Jones to be Coordinator of the Respiratory Programme.

Respiratory Medicine at McMaster University, Hamilton, Ontario: 1968 To 2013

Directory of Open Access Journals (Sweden)

Norman L Jones

2014-01-01

Full Text Available The medical school at McMaster University (Hamilton, Ontario was conceived in 1965 and admitted the first class in 1969. John Evans became the founding Dean and he invited Moran Campbell to be the first Chairman of the Department of Medicine. Moran Campbell, already a world figure in respiratory medicine and physiology, arrived at McMaster in September 1968, and he invited Norman Jones to be Coordinator of the Respiratory Programme.

Hamilton-Jacobi-Bellman approach for the climbing problem for heavy launchers

OpenAIRE

Bokanowski , Olivier; Cristiani , Emiliano; Laurent-Varin , Julien; Zidani , Hasnaa

2012-01-01

International audience; In this paper we investigate the Hamilton-Jacobi-Bellman (HJB) approach for solving a complex real-world optimal control problem in high dimension. We consider the climbing problem for the European launcher Ariane V: The launcher has to reach the Geostationary Transfer Orbit with minimal propellant consumption under state/control constraints. In order to circumvent the well-known curse of dimensionality, we reduce the number of variables in the model exploiting the spe...

Back to the Rio São Francisco valley

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Hervé Théry

2015-06-01

Full Text Available On the occasion of the Fourth French-Brazilian itinerant seminar, “Cities and river in the history of Brazil: Rio São Francisco”, the text revisits articles published in 1978, 1980 and 1981, illustrated with 1977 photographs and new maps. Though often portrayed as one of the most promising regions in Brazil, and despite having been object, for the last seventy years, of various development projects, the São Francisco valley remains one of the most underdeveloped areas of the country. The history of its occupation partly accounts for this situation, as the São Francisco is the river of the sertão. The various attempts at reclaiming the region, since 1946, are due to various motives, some of them political, but they are also due to a mythical view of the São Francisco as being the “river of national unity”. From 1948 to 1967, the CVSF was rather unsuccessful, probably given too many tasks to carry out. Since 1967, the Suvale and then the Codevasf have focused their action on a few areas in which their main activity is irrigation, but the needs of hydroelectric-power threatens its development. The competition for water therefore makes it necessary to reappraise the future of the valley, gradually integrated into the economy of Brazil’s coastal regions.

On global solutions of the random Hamilton-Jacobi equations and the KPZ problem

Science.gov (United States)

Bakhtin, Yuri; Khanin, Konstantin

2018-04-01

In this paper, we discuss possible qualitative approaches to the problem of KPZ universality. Throughout the paper, our point of view is based on the geometrical and dynamical properties of minimisers and shocks forming interlacing tree-like structures. We believe that the KPZ universality can be explained in terms of statistics of these structures evolving in time. The paper is focussed on the setting of the random Hamilton-Jacobi equations. We formulate several conjectures concerning global solutions and discuss how their properties are connected to the KPZ scalings in dimension 1  +  1. In the case of general viscous Hamilton-Jacobi equations with non-quadratic Hamiltonians, we define generalised directed polymers. We expect that their behaviour is similar to the behaviour of classical directed polymers, and present arguments in favour of this conjecture. We also define a new renormalisation transformation defined in purely geometrical terms and discuss conjectural properties of the corresponding fixed points. Most of our conjectures are widely open, and supported by only partial rigorous results for particular models.

CSIR Annual report 1980

CSIR Research Space (South Africa)

CSIR

1980-01-01

Full Text Available This report presents the thirty-sixth annual report of the CSIR. The report covers the period 1 January, 1980 to 31 December 1980. A balance sheet and statements of income and expenditure for the financial year ended 31st March 1980, certified...

Hamilton's gradient estimate for the heat kernel on complete manifolds

OpenAIRE

Kotschwar, Brett

2007-01-01

In this paper we extend a gradient estimate of R. Hamilton for positive solutions to the heat equation on closed manifolds to bounded positive solutions on complete, non-compact manifolds with $Rc \\geq -Kg$. We accomplish this extension via a maximum principle of L. Karp and P. Li and a Bernstein-type estimate on the gradient of the solution. An application of our result, together with the bounds of P. Li and S.T. Yau, yields an estimate on the gradient of the heat kernel for complete manifol...

Multimodal electromechanical model of piezoelectric transformers by Hamilton's principle.

Science.gov (United States)

Nadal, Clement; Pigache, Francois

2009-11-01

This work deals with a general energetic approach to establish an accurate electromechanical model of a piezoelectric transformer (PT). Hamilton's principle is used to obtain the equations of motion for free vibrations. The modal characteristics (mass, stiffness, primary and secondary electromechanical conversion factors) are also deduced. Then, to illustrate this general electromechanical method, the variational principle is applied to both homogeneous and nonhomogeneous Rosen-type PT models. A comparison of modal parameters, mechanical displacements, and electrical potentials are presented for both models. Finally, the validity of the electrodynamical model of nonhomogeneous Rosen-type PT is confirmed by a numerical comparison based on a finite elements method and an experimental identification.

77 FR 52058 - Notice of Inventory Completion: Longyear Museum of Anthropology, Colgate University, Hamilton, NY

Science.gov (United States)

2012-08-28

... Inventory Completion: Longyear Museum of Anthropology, Colgate University, Hamilton, NY AGENCY: National Park Service, Interior. ACTION: Notice. SUMMARY: The Longyear Museum of Anthropology has completed an... cultural affiliation with the human remains should contact the Longyear Museum of Anthropology at the...

Existence of solutions for Hamiltonian field theories by the Hamilton-Jacobi technique

International Nuclear Information System (INIS)

Bruno, Danilo

2011-01-01

The paper is devoted to prove the existence of a local solution of the Hamilton-Jacobi equation in field theory, whence the general solution of the field equations can be obtained. The solution is adapted to the choice of the submanifold where the initial data of the field equations are assigned. Finally, a technique to obtain the general solution of the field equations, starting from the given initial manifold, is deduced.

Valley polarization in bismuth

Science.gov (United States)

Fauque, Benoit

2013-03-01

The electronic structure of certain crystal lattices can contain multiple degenerate valleys for their charge carriers to occupy. The principal challenge in the development of valleytronics is to lift the valley degeneracy of charge carriers in a controlled way. In bulk semi-metallic bismuth, the Fermi surface includes three cigar-shaped electron valleys lying almost perpendicular to the high symmetry axis known as the trigonal axis. The in-plane mass anisotropy of each valley exceeds 200 as a consequence of Dirac dispersion, which drastically reduces the effective mass along two out of the three orientations. According to our recent study of angle-dependent magnetoresistance in bismuth, a flow of Dirac electrons along the trigonal axis is extremely sensitive to the orientation of in-plane magnetic field. Thus, a rotatable magnetic field can be used as a valley valve to tune the contribution of each valley to the total conductivity. As a consequence of a unique combination of high mobility and extreme mass anisotropy in bismuth, the effect is visible even at room temperature in a magnetic field of 1 T. Thus, a modest magnetic field can be used as a valley valve in bismuth. The results of our recent investigation of angle-dependent magnetoresistance in other semi-metals and doped semiconductors suggest that a rotating magnetic field can behave as a valley valve in a multi-valley system with sizeable mass anisotropy.

Greening Turner Valley

International Nuclear Information System (INIS)

Byfield, M.

2010-01-01

This article discussed remedial activities undertaken in the Turner Valley. Remedial action in the valley must satisfy the financial concerns of engineers and investors as well as the environmental concerns of residents and regulators. Natural gas production in the Turner Valley began in 1914. The production practices were harmful and wasteful. Soil and water pollution was not considered a problem until recently. The impacts of cumulative effects and other pollution hazards are now being considered as part of many oil and gas environmental management programs. Companies know it is cheaper and safer to prevent pollutants from being released, and more efficient to clean them up quickly. Oil and gas companies are also committed to remediating historical problems. Several factors have simplified remediation plans in the Turner Valley. Area real estate values are now among the highest in Alberta. While the valley residents are generally friendly to the petroleum industry, strong communication with all stakeholders in the region is needed. 1 fig.

Ongoing hydrothermal heat loss from the 1912 ash-flow sheet, Valley of Ten Thousand Smokes, Alaska

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Hogeweg, N.; Keith, T.E.C.; Colvard, E.M.; Ingebritsen, S.E.

2005-01-01

The June 1912 eruption of Novarupta filled nearby glacial valleys on the Alaska Peninsula with ash-flow tuff (ignimbrite), and post-eruption observations of thousands of steaming fumaroles led to the name 'Valley of Ten Thousand Smokes' (VTTS). By the late 1980s most fumarolic activity had ceased, but the discovery of thermal springs in mid-valley in 1987 suggested continued cooling of the ash-flow sheet. Data collected at the mid-valley springs between 1987 and 2001 show a statistically significant correlation between maximum observed chloride (Cl) concentration and temperature. These data also show a statistically significant decline in the maximum Cl concentration. The observed variation in stream chemistry across the sheet strongly implies that most solutes, including Cl, originate within the area of the VTTS occupied by the 1912 deposits. Numerous measurements of Cl flux in the Ukak River just below the ash-flow sheet suggest an ongoing heat loss of ???250 MW. This represents one of the largest hydrothermal heat discharges in North America. Other hydrothermal discharges of comparable magnitude are related to heat obtained from silicic magma bodies at depth, and are quasi-steady on a multidecadal time scale. However, the VTTS hydrothermal flux is not obviously related to a magma body and is clearly declining. Available data provide reasonable boundary and initial conditions for simple transient modeling. Both an analytical, conduction-only model and a numerical model predict large rates of heat loss from the sheet 90 years after deposition.

Negative correlation between nuptial throat colour and blood parasite load in male European green lizards supports the Hamilton-Zuk hypothesis

Science.gov (United States)

Molnár, Orsolya; Bajer, Katalin; Mészáros, Boglárka; Török, János; Herczeg, Gábor

2013-06-01

During female mate choice, conspicuous male sexual signals are used to infer male quality and choose the best sire for the offspring. The theory of parasite-mediated sexual selection (Hamilton-Zuk hypothesis) presumes that parasite infection can influence the elaboration of sexual signals: resistant individuals can invest more energy into signal expression and thus advertise their individual quality through signal intensity. By preferring these males, females can provide resistance genes for their offspring. Previous research showed that nuptial throat colour of male European green lizard, Lacerta viridis, plays a role in both inter- and intrasexual selections as a condition-dependent multiple signalling system. The aim of this study was to test the predictions of the Hamilton-Zuk hypothesis on male European green lizards. By blood sampling 30 adult males during the reproductive season, we found members of the Haemogregarinidae family in all but one individual (prevalence = 96 %). The infection intensity showed strong negative correlation with the throat and belly colour brightness in line with the predictions of the Hamilton-Zuk hypothesis. In addition, we found other correlations between infection intensity and other fitness-related traits, suggesting that parasite load has a remarkable effect on individual fitness. This study shows that throat patch colour of the European green lizards not only is a multiple signalling system but also possibly acts as an honest sexual signal of health state in accordance with the Hamilton-Zuk hypothesis.

Research highlights for the period February 1, 1980-July 31, 1980

International Nuclear Information System (INIS)

Shoemaker, F.C.

1980-01-01

Very brief summaries of research during the period February 1, 1980 to July 31, 1980 are given. The subjects included muon interactions, charmed particles, muon pair production, and the eta/sub c/ meson. Completed work has been published

76 FR 48178 - Notice of Inventory Completion: Longyear Museum of Anthropology, Colgate University, Hamilton, NY

Science.gov (United States)

2011-08-08

...: Longyear Museum of Anthropology, Colgate University, Hamilton, NY AGENCY: National Park Service, Interior. ACTION: Notice. SUMMARY: The Longyear Museum of Anthropology has completed an inventory of a human remain... human remain should contact the Longyear Museum of Anthropology at the address below by September 7...

'Morals can not be drawn from facts but guidance may be': the early life of W.D. Hamilton's theory of inclusive fitness.

Science.gov (United States)

Swenson, Sarah A

2015-12-01

W.D. Hamilton's theory of inclusive fitness saw the evolution of altruism from the point of view of the gene. It was at heart a theory of limits, redefining altruistic behaviours as ultimately selfish. This theory inspired two controversial texts published almost in tandem, E.O. Wilson's Sociobiology: The New Synthesis (1975) and Richard Dawkins's The Selfish Gene (1976). When Wilson and Dawkins were attacked for their evolutionary interpretations of human societies, they claimed a distinction between reporting what is and declaring what ought to be. Can the history of sociobiological theories be so easily separated from its sociopolitical context? This paper draws upon unpublished materials from the 1960s and early 1970s and documents some of the ways in which Hamilton saw his research as contributing to contemporary concerns. It pays special attention to the 1969 Man and Beast Smithsonian Institution symposium in order to explore the extent to which Hamilton intended his theory to be merely descriptive versus prescriptive. From this, we may see that Hamilton was deeply concerned about the political chaos he perceived in the world around him, and hoped to arrive at a level of self-understanding through science that could inform a new social order.

78 FR 28838 - Hamilton Street Hydro, LLC; Notice of Preliminary Permit Application Accepted for Filing and...

Science.gov (United States)

2013-05-16

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 14507-000] Hamilton Street... Project would consist of the following: (1) An existing 10.5-foot-high rock fill gravity dam with a 655... a storage [[Page 28839

West Valley demonstration project: alternative processes for solidifying the high-level wastes

International Nuclear Information System (INIS)

Holton, L.K.; Larson, D.E.; Partain, W.L.; Treat, R.L.

1981-10-01

In 1980, the US Department of Energy (DOE) established the West Valley Solidification Project as the result of legislation passed by the US Congress. The purpose of this project was to carry out a high level nuclear waste management demonstration project at the Western New York Nuclear Service Center in West Valley, New York. The DOE authorized the Pacific Northwest Laboratory (PNL), which is operated by Battelle Memorial Institute, to assess alternative processes for treatment and solidification of the WNYNSC high-level wastes. The Process Alternatives Study is the suject of this report. Two pretreatment approaches and several waste form processes were selected for evaluation in this study. The two waste treatment approaches were the salt/sludge separation process and the combined waste process. Both terminal and interim waste form processes were studied. The terminal waste form processes considered were: borosilicate glass, low-alkali glass, marbles-in-lead matrix, and crystallinolecular potential and molecular dynamics calculations of the effect are yet to be completed. Cous oxide was also investigated. The reaction is first order in nitrite ion, second order in hydrogen ion, and between zero and first order in hydroxylamine monosulfonate, depending on the concentration

Quantitative Compactness Estimates for Hamilton-Jacobi Equations

Science.gov (United States)

Ancona, Fabio; Cannarsa, Piermarco; Nguyen, Khai T.

2016-02-01

We study quantitative compactness estimates in {W^{1,1}_{loc}} for the map {S_t}, {t > 0} that is associated with the given initial data {u_0in Lip (R^N)} for the corresponding solution {S_t u_0} of a Hamilton-Jacobi equation u_t+Hbig(nabla_{x} ubig)=0, qquad t≥ 0,quad xinR^N, with a uniformly convex Hamiltonian {H=H(p)}. We provide upper and lower estimates of order {1/\\varepsilon^N} on the Kolmogorov {\\varepsilon}-entropy in {W^{1,1}} of the image through the map S t of sets of bounded, compactly supported initial data. Estimates of this type are inspired by a question posed by Lax (Course on Hyperbolic Systems of Conservation Laws. XXVII Scuola Estiva di Fisica Matematica, Ravello, 2002) within the context of conservation laws, and could provide a measure of the order of "resolution" of a numerical method implemented for this equation.

14 CFR 99.19-99.31 - [Reserved

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false [Reserved] 99.19-99.31 Section 99.19-99.31 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES SECURITY CONTROL OF AIR TRAFFIC General §§ 99.19-99.31 [Reserved] ...

Valley-filtered edge states and quantum valley Hall effect in gated bilayer graphene.

Science.gov (United States)

Zhang, Xu-Long; Xu, Lei; Zhang, Jun

2017-05-10

Electron edge states in gated bilayer graphene in the quantum valley Hall (QVH) effect regime can carry both charge and valley currents. We show that an interlayer potential splits the zero-energy level and opens a bulk gap, yielding counter-propagating edge modes with different valleys. A rich variety of valley current states can be obtained by tuning the applied boundary potential and lead to the QVH effect, as well as to the unbalanced QVH effect. A method to individually manipulate the edge states by the boundary potentials is proposed.

7 CFR 1980.401 - Introduction.

Science.gov (United States)

2010-01-01

... 7 Agriculture 14 2010-01-01 2009-01-01 true Introduction. 1980.401 Section 1980.401 Agriculture Regulations of the Department of Agriculture (Continued) RURAL HOUSING SERVICE, RURAL BUSINESS-COOPERATIVE... REGULATIONS (CONTINUED) GENERAL Business and Industrial Loan Program § 1980.401 Introduction. (a) Direct...

7 CFR 1980.331 - Collateral.

Science.gov (United States)

2010-01-01

... 7 Agriculture 14 2010-01-01 2009-01-01 true Collateral. 1980.331 Section 1980.331 Agriculture... REGULATIONS (CONTINUED) GENERAL Rural Housing Loans § 1980.331 Collateral. (a) General. The entire loan must... borrower. (c) All collateral must secure the entire loan. The Lender will not take separate collateral...

Mobile Air Monitoring: Measuring Change in Air Quality in the City of Hamilton, 2005-2010

Science.gov (United States)

Adams, Matthew D.; DeLuca, Patrick F.; Corr, Denis; Kanaroglou, Pavlos S.

2012-01-01

This paper examines the change in air pollutant concentrations between 2005 and 2010 occurring in the City of Hamilton, Ontario, Canada. After analysis of stationary air pollutant concentration data, we analyze mobile air pollutant concentration data. Air pollutants included in the analysis are CO, PM[subscript 2.5], SO[subscript 2], NO,…

Valley development on Hawaiian volcanoes

International Nuclear Information System (INIS)

Baker, V.R.; Gulick, V.C.

1987-01-01

Work in progress on Hawaiian drainage evolution indicates an important potential for understanding drainage development on Mars. Similar to Mars, the Hawaiian valleys were initiated by surface runoff, subsequently enlarged by groundwater sapping, and eventually stabilized as aquifers were depleted. Quantitative geomorphic measurements were used to evaluate the following factors in Hawaiian drainage evolution: climate, stream processes, and time. In comparing regions of similar climate, drainage density shows a general increase with the age of the volcani island. With age and climate held constant, sapping dominated valleys, in contrast to runoff-dominated valleys, display the following: lower drainage densities, higher ratios of valley floor width to valley height, and more positive profile concavities. Studies of stream junction angles indicate increasing junction angles with time on the drier leeward sides of the major islands. The quantitative geomorphic studies and earlier field work yielded important insights for Martian geomorphology. The importance of ash mantling in controlling infiltration on Hawaii also seems to apply to Mars. The Hawaiian valley also have implications for the valley networks of Martian heavily cratered terrains

Traditional Korean islanders encounters with the British navy in the 1880s: The Port Hamilton Affair of 1885–1887

Directory of Open Access Journals (Sweden)

Stephen A. Royle

2016-06-01

Full Text Available This article deals with the encounters between a traditional Korean rural and island population and western military forces when the British navy occupied Geomundo, an archipelago known to them as Port Hamilton, for 22 months between 1885 and 1887. The paper first outlines the sometimes painful process of East Asian countries being opened up to trade and outside influences in the 19th century, a process sometimes urged upon them by naval weapons in this era of gunboat diplomacy. This provides the setting for the Port Hamilton Affair itself when in preparation for possible war with Russia, a British naval squadron steamed into Port Hamilton and took it without reference to the local people or their national government. After brief reference to the political consequences of this action, the focus is then on what the records from the occupation and earlier investigations by the British, who had long coveted the islands’ strategic harbour, reveal about the life of the islanders. The article considers both their traditional life, from a time rather before western travel accounts were written about the Korean mainland, and how the islanders fared under the British.

On the Geometry of the Hamilton-Jacobi Equation and Generating Functions

Science.gov (United States)

Ferraro, Sebastián; de León, Manuel; Marrero, Juan Carlos; Martín de Diego, David; Vaquero, Miguel

2017-10-01

In this paper we develop a geometric version of the Hamilton-Jacobi equation in the Poisson setting. Specifically, we "geometrize" what is usually called a complete solution of the Hamilton-Jacobi equation. We use some well-known results about symplectic groupoids, in particular cotangent groupoids, as a keystone for the construction of our framework. Our methodology follows the ambitious program proposed by Weinstein (In Mechanics day (Waterloo, ON, 1992), volume 7 of fields institute communications, American Mathematical Society, Providence, 1996) in order to develop geometric formulations of the dynamical behavior of Lagrangian and Hamiltonian systems on Lie algebroids and Lie groupoids. This procedure allows us to take symmetries into account, and, as a by-product, we recover results from Channell and Scovel (Phys D 50(1):80-88, 1991), Ge (Indiana Univ. Math. J. 39(3):859-876, 1990), Ge and Marsden (Phys Lett A 133(3):134-139, 1988), but even in these situations our approach is new. A theory of generating functions for the Poisson structures considered here is also developed following the same pattern, solving a longstanding problem of the area: how to obtain a generating function for the identity transformation and the nearby Poisson automorphisms of Poisson manifolds. A direct application of our results gives the construction of a family of Poisson integrators, that is, integrators that conserve the underlying Poisson geometry. These integrators are implemented in the paper in benchmark problems. Some conclusions, current and future directions of research are shown at the end of the paper.

From the Snell-Descartes refraction law, to the Hamilton equations in the phase space of geometrical optics

International Nuclear Information System (INIS)

Lopez Moreno, E.; Wolf, K.B.

1989-01-01

Starting from the Snell-Descartes' refraction law, we obtain in a brief and direct way the Hamilton equations of Geometrical Optics. We show the global structure of phase space and compare it with that used in paraxial optics. (Author)

Variations in Sense of Place Across Immigrant Status and Gender in Hamilton, Ontario; Saskatoon, Saskatchewan; and, Charlottetown, Prince Edward Island, Canada.

Science.gov (United States)

Gallina, Melissa; Williams, Allison

Past research in Hamilton, Ontario has found that age and longevity of residence are positively associated with evaluations of sense of place (SoP); further, evaluations of SoP between immigrants and Canadian-born individuals have shown no clear pattern (Williams et al. 2010; Williams and Kitchen 2012). This paper builds on this work by further examining evaluations of SoP among both immigrants and Canadian-born residents and across gender in Hamilton, while expanding the study to two other small-to-medium sized cities: Saskatoon, Saskatchewan and, Charlottetown, Prince Edward Island. This paper has two objectives: (1) to establish measures of SoP across immigrant status and gender in Hamilton, Saskatoon, and Charlottetown; and, (2) to determine how SoP varies according to immigrant status, length of residence in Canada, age, income, and neighbourhood length of residence across the three city sites. Telephone survey data (n = 1,132) was used to compare evaluations of SoP across various groups and to construct an ordered logistic regression model for SoP. Results suggest that immigrants tended to rate their SoP lower than their Canadian-born counterparts. Hamilton residents were found to rate their SoP lowest, followed by Saskatoon residents and, finally, Charlottetown residents. Younger individuals, those with lower income levels, and those with shorter neighbourhood residency in the cities concerned were more likely to have lower evaluations of SoP. This research suggests that greater attention is needed to nurture immigrants' connection with their new home.

DURAND NEIGHBOURHOOD HERITAGE INVENTORY: TOWARD A DIGITAL CITYWIDE SURVEY APPROACH TO HERITAGE PLANNING IN HAMILTON

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V. Angel

2017-08-01

Full Text Available In the face of changing economies and patterns of development, the definition of heritage is diversifying, and the role of inventories in local heritage planning is coming to the fore. The Durand neighbourhood is a layered and complex area located in inner-city Hamilton, Ontario, Canada, and the second subject area in a set of pilot inventory studies to develop a new city-wide inventory strategy for the City of Hamilton,. This paper presents an innovative digital workflow developed to undertake the Durand Built Heritage Inventory project. An online database was developed to be at the centre of all processes, including digital documentation, record management, analysis and variable outputs. Digital tools were employed for survey work in the field and analytical work in the office, resulting in a GIS-based dataset that can be integrated into Hamilton’s larger municipal planning system. Together with digital mapping and digitized historical resources, the Durand database has been leveraged to produce both digital and static outputs to shape recommendations for the protection of Hamilton’s heritage resources.

Evidence for two hard X-ray components in double power-law fits to the 1980 June 7 flare

Science.gov (United States)

Smith, Dean F.; Orwig, Larry E.

1988-01-01

The June 7, 1980 flare at 0312 UT was analyzed with double power-law fits on the basis of SMM hard X-ray burst spectrometer data. The flare is found to consist of seven peaks of characteristic time scale of about 8 sec followed by seven valleys which may contain significant peak components because of overlap. It is suggested that the possibility of thermal spectra for the peaks is unlikely. An investigation of the double power-law parameters through the third and fourth peaks revealed a hysteresis effect in the fourth peak. The present results have been interpreted in terms of a trap plus precipitation model.

78 FR 22873 - Hamilton Street Hydro, LLC; Notice of Preliminary Permit Application Accepted for Filing and...

Science.gov (United States)

2013-04-17

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 14500-000] Hamilton Street... Hydroelectric Project would consist of the following: (1) An existing 14-foot-high concrete gravity dam with a 480-foot-long spillway; (2) an existing impoundment having a surface area of 50 acres and a storage...

Determination of 99Mo contamination in 99mTc elute obtained from 99Mo/99mTc- generator

International Nuclear Information System (INIS)

Momennezhad, M.; Zakavi, S. R.; Sadeghi, R.

2010-01-01

99m Tc is a widely used radioisotope in nuclear medicine centers which is obtained by elution from Mo-99/Tc-99m generators. Usually the generators are either supplied by the Iran Atomic Energy Agency or by private companies from foreign countries. In this study we have measured 99 Mo contamination in 99m Tc elute from different generators in a period of one year. Materials and Methods: The radionuclide impurity of the 99m Tc elute were studied in two types of radionuclide generators (A: produced in Iran and B: Imported from other country). In-vitro measurements were performed using dose calibrator. Direct measurements were made, using a standard canister at the time of milking of the generators and also in Subsequent hours after milking. Results: The results showed a mean of 99 Mo impurity in generators A and B to be 0.00932±0.0043 and 0.0170±0.0127 respectively. Although the results showed that the 99 Mo contamination in 99 mTc elute was lesser than the maximum accepted activity limit of 0.015%, the difference in these two types may reflect different methods of productions of generator, as well as the quality control procedures. Conclusion: The mean of 99 Mo contamination in generators produced in Iran Atomic Energy Organization was lesser than generators imported from foreign origin.

Analysis of Mining-induced Valley Closure Movements

Science.gov (United States)

Zhang, C.; Mitra, R.; Oh, J.; Hebblewhite, B.

2016-05-01

Valley closure movements have been observed for decades in Australia and overseas when underground mining occurred beneath or in close proximity to valleys and other forms of irregular topographies. Valley closure is defined as the inward movements of the valley sides towards the valley centreline. Due to the complexity of the local geology and the interplay between several geological, topographical and mining factors, the underlying mechanisms that actually cause this behaviour are not completely understood. A comprehensive programme of numerical modelling investigations has been carried out to further evaluate and quantify the influence of a number of these mining and geological factors and their inter-relationships. The factors investigated in this paper include longwall positional factors, horizontal stress, panel width, depth of cover and geological structures around the valley. It is found that mining in a series passing beneath the valley dramatically increases valley closure, and mining parallel to valley induces much more closure than other mining orientations. The redistribution of horizontal stress and influence of mining activity have also been recognised as important factors promoting valley closure, and the effect of geological structure around the valley is found to be relatively small. This paper provides further insight into both the valley closure mechanisms and how these mechanisms should be considered in valley closure prediction models.

Minimizing Molybdenum 99 contamination in Technetium 99m Pertechnetate from the elution of 99Mo/ 99m Tc Generator

International Nuclear Information System (INIS)

Zakaria Ibrahim; Zulkifli Hashim; Bohari Yaacob

2011-01-01

Radioisotope Tc-99m is widely used for variety of nuclear medicine diagnostic procedures. For many commercial applications, it is prepared in a portable type generator. Nuclear Malaysia has been producing a dry type alumina chromatographic column generator utilizing fission Mo-99. This injectable Tc-99m must meet the British Pharmacopeia [1] product specification prior to be apply on patient. This paper provides a method to minimize the up to acceptable level Mo-99 in the final product. Purposely made pertechnetate contaminated with Mo-99 and re-eluate by using old generator. Excellent removal of Mo-99 impurity was achieved and more than 80 % of Tc-99m total activity was recovered. (author)

Calculation of blade-data for the Hamilton standard structural analysis of the composite blade for the 18 meter diameter rotor and a comparison with FFA-calculation

Energy Technology Data Exchange (ETDEWEB)

Lundemo, C

1979-04-01

Section property data for the composite blade manufactured by Karlskronavarvet was calculated for the analysis performed by Hamilton Standard. The HS investigation was carried out for various operating conditions, including dynamic response loads, stresses, frequencies and dynamic stability. The Hamilton Standard results has been compared with the FFA (The Aeronautical Research Institute of Sweden) calculation. The results show that the stresses and moments calculated by HS never exceed the allowable levels for the hinged hub configuration. The natural frequencies seem to agree quite well with the measured frequencies. In the input data of the Hamilton Standard dynamic response analysis a too far aft position of the cordwise center of gravity of the outher third of the blade was used. Correct position will give lower stresses.

Hamilton Place - Ontario Canadá

Directory of Open Access Journals (Sweden)

Garwood-Jones, T. P.

1975-04-01

Full Text Available Although comparatively modest as to its exterior, the interior of the theatre-auditorium Hamilton Place has been most successfully solved, both as regards design and acoustics. Construction techniques and elements have been utilized to achieve two different sections in one and the same hall with on one hand the capacity to be able to capture shades of the spoken word at theatrical functions and on the other to reproduce the sharpness and variety of orchestras and choirs. The following elements deserve special mention: the mobile wall which incorporates the orchestra into the hall by closing the proscenium arch; the two elevating platforms where the orchestra is placed; the vertical velvet surfaces, hung like banners which soften the repercussion of the sound; the mobile horizontal surfaces over the orchestra that direct and orient the sound. The most interesting construction techniques are: the subdivision of the building into different parts, each one with independent foundation so as to avoid the transmission of the sound from one section to the other; the texture of the brick walls that disperse the reflected sound; and the use of counterforts to create smaller more personal sections for varied use. The acoustic characteristics are improved by means of a sound installation, formed by small loudspeakers placed under each seat and by other bigger ones distributed in the walls that surround the hall. The building is completed by various service installations that are appropriate to this type of construction, as well as by a small theatre-studio for the rehearsals of the orchestra and the actors, while other functions are going on in the main hall.El teatro-auditorio Hamilton Place, aunque relativamente modesto por fuera, tiene soluciones muy afortunadas en el interior, tanto por su diseño como por su adecuación acústica. Se han utilizado elementos y técnicas constructivas destinadas a conseguir, en una única sala, dos espacios

78 FR 22872 - Hamilton Street Hydro, LLC; Notice of Preliminary Permit Application Accepted for Filing and...

Science.gov (United States)

2013-04-17

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 14499-000] Hamilton Street... Project would consist of the following: (1) An existing 20-foot-high concrete gravity dam with a 690-foot-long spillway; (2) an existing impoundment having a surface area of 300 acres and a storage capacity of...

Birds of the St. Croix River valley: Minnesota and Wisconsin

Science.gov (United States)

Faanes, Craig A.

1981-01-01

The St. Croix River Valley encompasses nearly 11,550 km2 in east-central Minnesota and northwestern Wisconsin. A wide range of habitats are available for birds including upland oak, lowland deciduous, maple-basswood, lowland and upland coniferous forests, natural basin wetlands, and grasslands. Situated in the north-central region of the United States, the valley is a biological 'crossroads' for many species. Because of the mixed affinities of plant communities, the valley includes the northern and southern range limits for a number of species. Also, because the valley lies near the forest-prairie transition zone, many typical western breeding species (e.g. pintail, western meadowlark, yellow-headed blackbird) breed in proximity to typical eastern species such as tufted titmouse, eastern meadowlark, and cardinal. From 1966 to 1980, I conducted extensive surveys of avian distribution and abundance in the St. Croix River Valley. I have supplemented the results of these surveys with published and unpublished observations contributed by many ornithologists. These additional data include compilations from Christmas Bird Counts sponsored by the National Audubon Society and from the Breeding Bird Survey coordinated by the U.S. Fish and Wildlife Service. Three hundred fourteen species have been recorded in the study area; data are presented on the migration period, nesting season distribution, winter distribution, relative abundance, and habitat use of each species. Recognizing the uniqueness of the area, and its importance not only to wildlife but also to man, the U.S. Congress designated the St. Croix a National Scenic Riverway. This action provided a considerable degree of protection to lands along and directly adjacent to the river. Unfortunately, no similar legal measure exists to protect lands away from the river. With the exception of the northern quarter of the St. Croix River Valley, agricultural interests have made significant inroads into the habitat base. The

Spent 99Mo/99mTc generator as an economical source of 99Mo

International Nuclear Information System (INIS)

El-Kolaly, M.T.

1990-01-01

An improved method for utilization and purification of 99 Mo from spent 90 Mo/ 99m Tc generators has been described. After washing the generator with saline to remove the generated 99m Tc, followed by 2 mL 5 M NaOH containing a few drops of H 2 O 2 , the 99 Mo was quantitatively eluted from the generator with 5 mL 5 M NaOH. The alkaline eluate containing 99 Mo was contaminated with partially dissolved alumina. In the present method, an anion-exchange resin Dowex 1 x 8 column was used for purification of 99 Mo from the contaminating alumina. The resultant 99 Mo was of high purity and contained 3+ /mL 99 Mo solution, as estimated by atomic absorption. (author)

Dendroclimatic Reconstruction of Summer Temperatures in Irik Valley, Mount Elbrus (Greater Caucasus

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Iulian Horia HOLOBÂCĂ

2014-11-01

Full Text Available Recent evidence suggests an acceleration of glacier retreat in Greater Caucasus after 1980. For the same period a significant summer temperature warming trend and little or no change in precipitation variation have been observed. In this paper we seek to find similar past climatic conditions using a dendroclimatic reconstruction of summer temperatures from upper treeline sites after the Little Ice Age (LIA. Dendroclimatological sampling of Scots pine (Pinus sylvestris has been made in Irik Valley, near Elbrus glacier, and a tree-ring width (TRW chronology has been used to reconstruct May – August (MJJA temperatures back to 1830. Three warm periods were identified in the MJJA temperatures reconstructed data (1830 - 1900, but we cannot appreciate if they had the same intensity as the recent warm period

The role of interfacial layers in the enhanced thermal conductivity of nanofluids: A renovated Hamilton-Crosser model

International Nuclear Information System (INIS)

Yu, W; Choi, S.U.S.

2004-01-01

We previously developed a renovated Maxwell model for the effective thermal conductivity of nanofluids and determined that the solid/liquid interfacial layers play an important role in the enhanced thermal conductivity of nanofluids. However, this renovated Maxwell model is limited to suspensions with spherical particles. Here, we extend the Hamilton--Crosser model for suspensions of nonspherical particles to include the effect of a solid/liquid interface. The solid/liquid interface is described as a confocal ellipsoid with a solid particle. The new model for the three-phase suspensions is mathematically expressed in terms of the equivalent thermal conductivity and equivalent volume fraction of anisotropic complex ellipsoids, as well as an empirical shape factor. With a generalized empirical shape factor, the renovated Hamilton--Crosser model correctly predicts the magnitude of the thermal conductivity of nanotube-in-oil nanofluids. At present, this new model is not able to predict the nonlinear behavior of the nanofluid thermal conductivity

Additions and corrections to the bibliography of geologic studies, Columbia Plateau (Columbia River Besalt) and adjacent Areas, in Idaho, 1980

International Nuclear Information System (INIS)

Strowd, W.

1980-01-01

This bibliography is an update to Idaho Bureau of Mines and Geology Open-File Report 78-6, Bibliography of Geological Studies, Columbia Plateau (Columbia River Basalt Group) and adjacent areas in Idaho (also known as Rockwell Hanford Operations' contractor report RHO-BWI-C-44). To keep the original document current, this additions and corrections report was prepared for the Basalt Waste Isolation Project of Rockwell Hanford Operations. This update is supplementary; therefore, references cited in the original document have not been included here. What is included are materials that have become available since the original publication and pertinent literature that had originally been overlooked. Accompany this updated bubliography are index maps that show locations of geologic studies and geochemical petrographic, remanent paleomagnetic, and radiometric age-dated sites within the Columbia River Basalt Group field within Idaho; also identified are archeological sites, test wells, mines, quarries, and other types of excavations. References on the index maps are keyed to the bibliography and cover the Spokane, Pullman, Hamilton, Grangeville, Elk City, Baker, Boise, and Jordan Valley Army Map Service two-degree quadrangles

Hamilton-Jacobi formalism for inflation with non-minimal derivative coupling

International Nuclear Information System (INIS)

Sheikhahmadi, Haidar; Saridakis, Emmanuel N.; Aghamohammadi, Ali; Saaidi, Khaled

2016-01-01

In inflation with nonminimal derivative coupling there is not a conformal transformation to the Einstein frame where calculations are straightforward, and thus in order to extract inflationary observables one needs to perform a detailed and lengthy perturbation investigation. In this work we bypass this problem by performing a Hamilton-Jacobi analysis, namely rewriting the cosmological equations considering the scalar field to be the time variable. We apply the method to two specific models, namely the power-law and the exponential cases, and for each model we calculate various observables such as the tensor-to-scalar ratio, and the spectral index and its running. We compare them with 2013 and 2015 Planck data, and we show that they are in a very good agreement with observations.

Hamilton-Jacobi formalism for inflation with non-minimal derivative coupling

Energy Technology Data Exchange (ETDEWEB)

Sheikhahmadi, Haidar [Institute for Advance Studies in Basic Sciences (IASBS) Gava Zang, Zanjan 45137-66731 (Iran, Islamic Republic of); Saridakis, Emmanuel N. [Instituto de Física, Pontificia Universidad de Católica de Valparaíso, Casilla 4950, Valparaíso (Chile); Aghamohammadi, Ali [Sanandaj Branch Islamic Azad University (Iran, Islamic Republic of); Saaidi, Khaled, E-mail: h.sh.ahmadi@gmail.com, E-mail: Emmanuel_Saridakis@baylor.edu, E-mail: a.aqamohamadi@iausdj.ac.ir, E-mail: ksaaidi@uok.ac.ir [Department of Physics, Faculty of Science, University of Kurdistan, Sanandaj (Iran, Islamic Republic of)

2016-10-01

In inflation with nonminimal derivative coupling there is not a conformal transformation to the Einstein frame where calculations are straightforward, and thus in order to extract inflationary observables one needs to perform a detailed and lengthy perturbation investigation. In this work we bypass this problem by performing a Hamilton-Jacobi analysis, namely rewriting the cosmological equations considering the scalar field to be the time variable. We apply the method to two specific models, namely the power-law and the exponential cases, and for each model we calculate various observables such as the tensor-to-scalar ratio, and the spectral index and its running. We compare them with 2013 and 2015 Planck data, and we show that they are in a very good agreement with observations.

Changes in the status of harvested rice fields in the Sacramento Valley, California: Implications for wintering waterfowl.

Science.gov (United States)

Miller, Michael R.; Garr, Jay D.; Coates, Peter S.

2010-01-01

Harvested rice fields provide critical foraging habitat for wintering waterfowl in North America, but their value depends upon post-harvest treatments. We visited harvested ricefields in the Sacramento Valley, California, during the winters of 2007 and 2008 (recent period) and recorded their observed status as harvested (standing or mechanically modified stubble), burned, plowed, or flooded. We compared these data with those from identical studies conducted during the 1980s (early period). We documented substantial changes in field status between periods. First, the area of flooded rice increased 4-5-fold, from about 15% to >40% of fields, because of a 3-4-fold increase in the percentage of fields flooded coupled with a 37-41% increase in the area of rice produced. Concurrently, the area of plowed fields increased from 35% of fields, burned fields declined from about 40% to 1%, and fields categorized as harvested declined from 22-54% to rice field status survey in the Sacramento Valley and other North American rice growing regions as appropriate to support long-term monitoring programs and wetland habitat conservation planning for wintering waterfowl.

Environmental surveillance report for the Nevada Test Site (January 1980-December 1980)

International Nuclear Information System (INIS)

Scoggins, W.A.

1981-01-01

Results are presented for the environmental surveillance program at the Nevada Test Site as conducted by the Department of Energy (DOE) onsite radiological safety contractor from January 1980 through December 1980. The results and evaluations of measurements of radioactivity in air and water, and of direct gamma radiation exposure rates are presented. Relevancy to DOE concentration guides (CG'S) is established

40 CFR 86.1729-99-86.1733-99 - [Reserved

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 19 2010-07-01 2010-07-01 false [Reserved] 86.1729-99-86.1733-99 Section 86.1729-99-86.1733-99 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Light-Duty Trucks §§ 86.1729-99—86.1733-99 [Reserved] ...

40 CFR 86.1736-99-86.1769-99 - [Reserved

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 19 2010-07-01 2010-07-01 false [Reserved] 86.1736-99-86.1769-99 Section 86.1736-99-86.1769-99 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Light-Duty Trucks §§ 86.1736-99—86.1769-99 [Reserved] ...

40 CFR 86.1718-99-86.1720-99 - [Reserved

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 19 2010-07-01 2010-07-01 false [Reserved] 86.1718-99-86.1720-99 Section 86.1718-99-86.1720-99 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Light-Duty Trucks §§ 86.1718-99—86.1720-99 [Reserved] ...

21 CFR 892.1980 - Radiologic table.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Radiologic table. 892.1980 Section 892.1980 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES RADIOLOGY DEVICES Diagnostic Devices § 892.1980 Radiologic table. (a) Identification. A radiologic...

7 CFR 1980.370 - Loan servicing.

Science.gov (United States)

2010-01-01

... 7 Agriculture 14 2010-01-01 2009-01-01 true Loan servicing. 1980.370 Section 1980.370 Agriculture... REGULATIONS (CONTINUED) GENERAL Rural Housing Loans § 1980.370 Loan servicing. RHS encourages Lenders to... sufficient servicing and counseling to meet the objectives of the loan. Loan servicing should be approached...

Visual and infrared observations of the distant Comets P/Stephan-Oterma /1980g/, Panther /1980u/, and Bowell /1980b/

Science.gov (United States)

Jewitt, D. C.; Soifer, B. T.; Neugebauer, G.; Matthews, K.; Danielson, G. E.

1982-12-01

The paper reports combined visual imagery and spectroscopy, near-infrared spectroscopy, and broadband infrared photometry of comets P/Stephan-Oterma (1980g), Bowell (1980b), and Panther (1980u) at intermediate heliocentric distances. The visual data indicate the existence of solid grains in extended halos around the nuclei of the three comets. Broadband near-infrared and thermal infrared measurements of Comet Panther suggest the presence of 2-4-micron-radius particles in the coma which most likely contain molecules incorporating the N-H bond, but which are more complex and less volatile than NH3. Such molecules can be produced in the grains by cosmic-ray reprocessing. Near infrared spectral features identical to those seen in comet Panther similary suggest the presence of a molecule incorporating the N-H bond in comet Bowell.

Hamilton's equations for a fluid membrane

International Nuclear Information System (INIS)

Capovilla, R; Guven, J; Rojas, E

2005-01-01

Consider a homogeneous fluid membrane described by the Helfrich-Canham energy, quadratic in the mean curvature of the membrane surface. The shape equation that determines equilibrium configurations is fourth order in derivatives and cubic in the mean curvature. We introduce a Hamiltonian formulation of this equation which dismantles it into a set of coupled first-order equations. This involves interpreting the Helfrich-Canham energy as an action; equilibrium surfaces are generated by the evolution of space curves. Two features complicate the implementation of a Hamiltonian framework. (i) The action involves second derivatives. This requires treating the velocity as a phase-space variable and the introduction of its conjugate momentum. The canonical Hamiltonian is constructed on this phase space. (ii) The action possesses a local symmetry-reparametrization invariance. The two labels we use to parametrize points on the surface are themselves physically irrelevant. This symmetry implies primary constraints, one for each label, that need to be implemented within the Hamiltonian. The two Lagrange multipliers associated with these constraints are identified as the components of the acceleration tangential to the surface. The conservation of the primary constraints implies two secondary constraints, fixing the tangential components of the momentum conjugate to the position. Hamilton's equations are derived and the appropriate initial conditions on the phase-space variables are identified. Finally, it is shown how the shape equation can be reconstructed from these equations

Successful labeling of 99mTc-MDP using 99mTc separated from 99Mo produced by 100Mo(n,2n)99Mo

International Nuclear Information System (INIS)

Nagai, Yasuki; Hatsukawa, Yuichi; Kin, Tadahiro; Hashimoto, Kazuyuki; Motoishi, Shoji; Konno, Chikara; Ochiai, Kentaro; Takakura, Kosuke; Sato, Yuichi; Sato, Norihito; Ohta, Akio; Yamabayashi, Hisamichi; Tanase, Masakazu; Fujisaki, Saburo; Kawauchi, Yukimasa; Teranaka, Tomoyuki; Takeuchi, Nobuhiro; Igarashi, Takashi

2011-01-01

We have for the first time succeeded in separating 99m Tc from a MoO 3 sample irradiated with accelerator neutrons free from any radioactive impurities and in formulating 99m Tc-methylene diphosphonate ( 99 mTc-MDP). 99 Mo, the mother nuclide of 99m Tc, was produced by the 100 Mo(n,2n) 99 Mo reaction using about 14 MeV neutrons provided by the 3 H(d,n) 4 He reaction at the Fusion Neutronics Source of Japan Atomic Energy Agency. The 99m Tc was separated from 99 Mo by sublimation and its radionuclide purity was confirmed to be higher than 99.99% by γ-spectroscopy. The labeling efficiency of 99m Tc-MDP was shown to be higher than 99% by thin-layer chromatography. These values exceed the United States Pharmacopeia requirements for a fission product, 99 Mo. Consequently, a 99m Tc radiopharmaceutical preparation formed by using the mentioned 99 Mo can be a promising substitute for the fission product 99 Mo, which is currently produced using a highly enriched uranium target in aging research reactors. A longstanding problem to ensure a reliable and constant supply of 99 Mo in Japan can be partially mitigated. (author)

7 CFR 1980.376 - Loss payments.

Science.gov (United States)

2010-01-01

... 7 Agriculture 14 2010-01-01 2009-01-01 true Loss payments. 1980.376 Section 1980.376 Agriculture Regulations of the Department of Agriculture (Continued) RURAL HOUSING SERVICE, RURAL BUSINESS-COOPERATIVE... appeal in accordance with § 1980.399 and subpart B of part 1900. (5) The RHS approval official is...

7 CFR 1980.423 - Interest rates.

Science.gov (United States)

2010-01-01

... 7 Agriculture 14 2010-01-01 2009-01-01 true Interest rates. 1980.423 Section 1980.423 Agriculture... REGULATIONS (CONTINUED) GENERAL Business and Industrial Loan Program § 1980.423 Interest rates. (a) Guaranteed... variable as long as they are legal. Interest rates will be those rates customarily charged borrowers in...

Tropical New World Glacier Recession from the mid-1980s to the mid-2000s

Science.gov (United States)

Slayback, D. A.; Tucker, C. J.

2010-12-01

We report on the systematic retreat of all glaciers in the tropics of the New World from the mid-1980s to the mid-2000s. These glaciers comprise 99% of the world’s tropical glaciers and occur in Bolivia, Peru, Ecuador, Colombia, Venezuela, and Mexico. It was necessary to use a large quantity of Landsat satellite data (124 images), selecting multiple images for every glacier for both epochs, to minimize confusion of glacier area with snow. Change in glacier extent was combined with a digital elevation model (DEM) to provide information on the elevation and aspect of areas of glacier recession. Overall, we found glacier recession of approximately 30% over twenty years, declining from ~2500 km2 from the mid-1980s to ~1800 km2 in the mid-2000s. In addition, there was a strong association of glacier recession with elevation and aspect. We discuss these trends in relation to hypothesized climatic influences.

A landscape scale valley confinement algorithm: Delineating unconfined valley bottoms for geomorphic, aquatic, and riparian applications

Science.gov (United States)

David E. Nagel; John M. Buffington; Sharon L. Parkes; Seth Wenger; Jaime R. Goode

2014-01-01

Valley confinement is an important landscape characteristic linked to aquatic habitat, riparian diversity, and geomorphic processes. This report describes a GIS program called the Valley Confinement Algorithm (VCA), which identifies unconfined valleys in montane landscapes. The algorithm uses nationally available digital elevation models (DEMs) at 10-30 m resolution to...

Small martian valleys: Pristine and degraded morphology

International Nuclear Information System (INIS)

Baker, V.R.; Partridge, J.B.

1986-01-01

The equatorial heavily cratered uplands of Mars are dissected by two classes of small valleys that are intimately associated in compound networks. Pristine valleys with steep valley walls preferentially occupy downstream portions of compound basins. Degraded valleys with eroded walls are laterally more extensive and have higher drainage densities than pristine valleys. Morphometric and crater-counting studies indicate that relatively dense drainage networks were emplaced on Mars during the heavy bombardment about 4.0 b.y. ago. Over a period of approximately 10 8 years, these networks were degraded and subsequently invaded by headwardly extending pristine valleys. The pristine valleys locally reactivated the compound networks, probably through sapping processes dependent upon high water tables. Fluvial activity in the heavily cratered uplands generally ceased approximately 3.8--3.9 b.y. ago, coincident with the rapid decline in cratering rates. The relict compound valleys on Mars are morphometrically distinct from most terrestrial drainage systems. The differences might be caused by a Martian valley formation episode characterized by hyperaridity, by inadequate time for network growth, by very permeable rock types, or by a combination of factors

7 CFR 1980.320 - Interest rate.

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2010-01-01

... 7 Agriculture 14 2010-01-01 2009-01-01 true Interest rate. 1980.320 Section 1980.320 Agriculture... REGULATIONS (CONTINUED) GENERAL Rural Housing Loans § 1980.320 Interest rate. The interest rate must not... interest rate over the life of the loan. The rate shall be agreed upon by the borrower and the Lender and...

7 CFR 1980.310 - Loan purposes.

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2010-01-01

... 7 Agriculture 14 2010-01-01 2009-01-01 true Loan purposes. 1980.310 Section 1980.310 Agriculture... REGULATIONS (CONTINUED) GENERAL Rural Housing Loans § 1980.310 Loan purposes. The purpose of a loan guaranteed... applicant as a primary residence. The loan may be to purchase a new dwelling or an existing dwelling. The...

Effect of milking efficiency on Tc-99 content of Tc-99m derived from Tc-99m generators

International Nuclear Information System (INIS)

Bonnyman, J.

1983-01-01

Tc-99m obtained by separation from its parent Mo-99 always contains Tc-99 produced by decay of Tc-99m and Mo-99. Factors effecting the Tc-99/Tc-99m ratios are discussed. An HPLC method has been developed to measure the 99 TcO 4- content of sodium pertechnetate from generators with a detection limit of 0.9 ng Tc-99 for a 500 μl/ aliquot of TcO 4- -99m. First eluates of 10 chromatograph-ic generators gave Tc-99/Tc-99m ratios ranging from 3.5-46 ng Tc/mCi Tc-99m measured at the time of milking. The measurements indicate that Tc-99/Tc-99m ratios high enough to cause adverse labelling effects could be found in 'instant pertechnetate' and in the first eluate from Tc-99m generators for the activities normally used in radiopharmaceutical production

Production technologies for molybdenum-99 and technetium-99m

International Nuclear Information System (INIS)

1999-02-01

Technetium-99m (6.02 h) is the most widely used radioisotope in nuclear medicine, accounting for more than 80% of all diagnostic nuclear medicine procedures. It is almost exclusively produced from the decay of its parent 99 Mo. The present sources of 99 Mo are research reactors by using the (n,γ) nuclear reaction with natural Mo ( 98 Mo, ∼24%), resulting in inexpensive but low-specific activity 99 Mo, or by neutron-induced fission of 235 U, which results in expensive but high specific activity 99 Mo. This publication covers several aspects related to the production of 99 Mo and 99m Tc. The contributed papers reflect the current status of the technology and discuss potential alternative methodologies for the production of 99 Mo and 99m Tc for medical use. The first four papers address the technologies using nuclear reactors, including the description of a new method using an aqueous homogenous reactor core for production of fission 99 Mo and the latest development efforts to fabricate 235 U low enriched targets (LEU, 235 U). The next five papers discuss the potential of utilizing particle accelerators and assess the current status of the available nuclear data for the production of both, 99 Mo and 99m Tc with proton and deuteron beams. The last paper discusses a new technology based on gel system for the preparation of 99 Mo/ 99m Tc generators using low specific activity 99 Mo produced in research reactors by the neutron activation of natural and inexpensive molybdenum oxide targets. Each individual paper was indexed and abstracted

Geologic summary of the Owens Valley drilling project, Owens and Rose Valleys, Inyo County, California

International Nuclear Information System (INIS)

Schaer, D.W.

1981-07-01

The Owens Valley Drilling Project consists of eight drill holes located in southwest Inyo County, California, having an aggregate depth of 19,205 feet (5853 m). Project holes penetrated the Coso Formation of upper Pliocene or early Pleistocene age and the Owens Lake sand and lakebed units of the same age. The project objective was to improve the reliability of uranium-potential-resource estimates assigned to the Coso Formation in the Owens Valley region. Uranium-potential-resource estimates for this area in $100 per pound U 3 O 8 forward-cost-category material have been estimatd to be 16,954 tons (15,384 metric tons). This estimate is based partly on project drilling results. Within the Owens Valley project area, the Coso Formation was encountered only in the Rose Valley region, and for this reason Rose Valley is considered to be the only portion of the project area favorable for economically sized uranium deposits. The sequence of sediments contained in the Owens Valley basin is considered to be largely equivalent but lithologically dissimilar to the Coso Formation of Haiwee Ridge and Rose Valley. The most important factor in the concentration of significant amounts of uranium in the rock units investigated appears to be the availability of reducing agents. Significant amounts of reductants (pyrite) were found in the Coso Formation. No organic debris was noted. Many small, disconnected uranium occurrences, 100 to 500 ppM U 3 O 8 , were encountered in several of the holes

Valley dependent transport in graphene L junction

Science.gov (United States)

Chan, K. S.

2018-05-01

We studied the valley dependent transport in graphene L junctions connecting an armchair lead and a zigzag lead. The junction can be used in valleytronic devices and circuits. Electrons injected from the armchair lead into the junction is not valley polarized, but they can become valley polarized in the zigzag lead. There are Fermi energies, where the current in the zigzag lead is highly valley polarized and the junction is an efficient generator of valley polarized current. The features of the valley polarized current depend sensitively on the widths of the two leads, as well as the number of dimers in the armchair lead, because this number has a sensitive effect on the band structure of the armchair lead. When an external potential is applied to the junction, the energy range with high valley polarization is enlarged enhancing its function as a generator of highly valley polarized current. The scaling behavior found in other graphene devices is also found in L junctions, which means that the results presented here can be extended to junctions with larger dimensions after appropriate scaling of the energy.

Environmental monitoring in the vicinity of the Savannah River Plant. Annual report, 1980

International Nuclear Information System (INIS)

1980-01-01

An extensive surveillance program has been continuously maintained since 1951 to determine the concentrations of radonuclides in a 1200-square-mile area in the environs of the plant and the radiation exposure of the population resulting from SRP operations. The results of this monitoring program are reported annually to the public. This document summarizes the 1980 results. The radiation dose at the plant perimeter and the population dose in the region from SRP operations is very small relative to the dose received from naturally occurring radiation. The annual average dose in 1980 from atmospheric releases of radioactive materials from SRP was 0.7 millirem at the plant perimeter. The maximum dose at the plant perimeter was 1.01 mrem, which is 0.2% of the Department of Energy limit for offsite exposures. The population dose to people living within 80 km of the center of SRP was 99.7 man-rems. During 1980, this same population received a radiation dose of 54,400 man-rems from natural radiation and an additional dose of 47,000 man-rems from medical x-rays. An individual consuming river water downstream from SRP would receive a maximum calculated dose in 1980 of 0.22 mrem which includes dose contributions from consumer products produced using Savannah River water. Air and water are the major dispersal media for radioactive emissions. Samples representing most segments of the environment that may conceivably be affected by these emissions were monitored to ensure a safe environment. Releases of radioactivity from SRP had an inconsequential effect on living plants and animals. With a few exceptions, concentrations outside the plant boundary were too low to distinguish from the natural radioactive background and continuing worldwide fallout from nuclear weapons tests

Excess Mortality and Causes of Death in Autism Spectrum Disorders: A Follow up of the 1980s Utah/UCLA Autism Epidemiologic Study

Science.gov (United States)

Bilder, Deborah; Botts, Elizabeth L.; Smith, Ken R.; Pimentel, Richard; Farley, Megan; Viskochil, Joseph; McMahon, William M.; Block, Heidi; Ritvo, Edward; Ritvo, Riva-Ariella; Coon, Hilary

2013-01-01

This study's purpose was to investigate mortality among individuals with autism spectrum disorders (ASD) ascertained during a 1980s statewide autism prevalence study (n = 305) in relation to controls. Twenty-nine of these individuals (9.5 %) died by the time of follow up, representing a hazard rate ratio of 9.9 (95 % CI 5.7-17.2) in relation to…

Strontium-90 and cesium-137 in tea (Japanese tea); from May 1980 to Jun. 1980

International Nuclear Information System (INIS)

1980-01-01

Five hundred grams of manufactured green tea was collected, carbonized and ashed in a stainless steel pan or a porcelain dish. The results obtained from May 1980 to June 1980 were shown in a table. (J.P.N.)

Tumor affinity of technetium-99m labeled radiopharmaceuticals. II. Sup(99m)Tc-Sn-diphosphonate (sup(99m)Tc-EHDP), sup(99m)Tc-Sn-dimercaptosuccinic acid (sup(99m)Tc-DMSA), sup(99m)Tc-Sn-diethyl stilbestrol diphosphate (sup(99m)Tc-DSDP)

Energy Technology Data Exchange (ETDEWEB)

Itoh, K; Kobayashi, S; Hisada, K; Tonami, N [Kanazawa Univ. (Japan). School of Medicine; Ando, A

1976-10-01

The authors have examined the tumor affinity of various sup(99m)Tc-labelled radiopharmaceuticals to Ehrlich's tumor for the purpose of delineating human malignant neoplasm positively. The biologic distributions of sup(99m)Tc-Sn-diphosphonate (sup(99m)Tc-EHDP), sup(99m)Tc-Sn-dimercaptosuccinic acid (sup(99m)Tc-DMSA) and sup(99m)Tc-Sn-diethyl stilbestrol diphosphate (sup(99m)Tc-DSDP, sup(99m)Tc-Honvan) are included as the second report on the tumor affinity of Ehrlich-bearing mice. Tumor concentration of sup(99m)Tc-EHDP was lowest and the positive delineation of implanted tumor with sup(99m)Tc-EHDP was poorest in sequential images, though active accumulation in some soft tissues malignant neoplasms, breast cancer, and thyroid cancer, has been reported. Tumor concentration and the tumor-to-blood ratio of sup(99m)Tc-DMSA were not so high, contrary to our expectation that /sup 197/Hg-DMSA might show high tumor concentration and high tumor-to-blood ratio the same as /sup 197/Hg chlormerodrin of the renal scanning radiopharmaceuticals. Tumor concentration of sup(99m)Tc-DSDP was highest. The tumor-to-blood concentration ratio was lower than that of the above mentioned radiopharmaceuticals but the tumor-to-liver ratio and/or tumor-to-lung ratio was over 1.0 at the earlier time. Biologic distribution of sup(99m)Tc-DSDP was similar to that of /sup 32/P labeled DSDP. It is presumed that sup(99m)Tc is labeled at the phosphate ester of DSDP which is dephospholytated immediately by phospholylase in vivo following intravenous injection. Although it is not known precisely it may be assumed that the mechanism of accumulating sup(99m)Tc-DSDP in Ehrlich's tumor is related to the phospholylase activity in neoplasms.

Source apportionment of PAH in Hamilton Harbour suspended sediments: comparison of two factor analysis methods.

Science.gov (United States)

Sofowote, Uwayemi M; McCarry, Brian E; Marvin, Christopher H

2008-08-15

A total of 26 suspended sediment samples collected over a 5-year period in Hamilton Harbour, Ontario, Canada and surrounding creeks were analyzed for a suite of polycyclic aromatic hydrocarbons and sulfur heterocycles. Hamilton Harbour sediments contain relatively high levels of polycyclic aromatic compounds and heavy metals due to emissions from industrial and mobile sources. Two receptor modeling methods using factor analyses were compared to determine the profiles and relative contributions of pollution sources to the harbor; these methods are principal component analyses (PCA) with multiple linear regression analysis (MLR) and positive matrix factorization (PMF). Both methods identified four factors and gave excellent correlation coefficients between predicted and measured levels of 25 aromatic compounds; both methods predicted similar contributions from coal tar/coal combustion sources to the harbor (19 and 26%, respectively). One PCA factor was identified as contributions from vehicular emissions (61%); PMF was able to differentiate vehicular emissions into two factors, one attributed to gasoline emissions sources (28%) and the other to diesel emissions sources (24%). Overall, PMF afforded better source identification than PCA with MLR. This work constitutes one of the few examples of the application of PMF to the source apportionment of sediments; the addition of sulfur heterocycles to the analyte list greatly aided in the source identification process.

Relationship Between the DSM-5 Anxious Distress Specifier and the Hamilton Depression Rating Scale Anxiety/Somatization Factor.

Science.gov (United States)

Zimmerman, Mark; Clark, Heather; McGonigal, Patrick; Harris, Lauren; Guzman Holst, Carolina; Martin, Jacob

2018-02-01

We examined the association between the Hamilton Depression Scale (HAMD) approach to classifying depressed patients into anxious and nonanxious subgroups and the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5) anxious distress specifier subtyping. Two hundred two depressed patients were interviewed with semistructured diagnostic interviews. Patients were rated on the 17-item HAMD and the Hamilton Anxiety Rating Scale and completed the Clinically Useful Anxiety Outcome Scale. Both approaches toward identifying anxiety in depressed patients resulted in most of the patients meeting the anxiety subtype. Both subtyping methods were significantly correlated with clinician-rated and self-report measures of anxiety, and scores on the anxiety scales were higher in the patients who met the anxious subtype. However, DSM-5 anxious distress subtyping was only marginally associated with the HAMD anxiety/somatization factor subtyping approach (k = 0.21), and dimensional scores were only moderately correlated (r = 0.50). These findings indicate that the DSM-5 and HAMD approaches toward identifying an anxious subtype of depression are not interchangeable.

Diversification of 99Mo/99mTc separation: non–fission reactor production of 99Mo as a strategy for enhancing 99mTc availability.

Science.gov (United States)

Pillai, Maroor R A; Dash, Ashutosh; Knapp, Furn F Russ

2015-01-01

This paper discusses the benefits of obtaining (99m)Tc from non-fission reactor-produced low-specific-activity (99)Mo. This scenario is based on establishing a diversified chain of facilities for the distribution of (99m)Tc separated from reactor-produced (99)Mo by (n,γ) activation of natural or enriched Mo. Such facilities have expected lower investments than required for the proposed chain of cyclotrons for the production of (99m)Tc. Facilities can receive and process reactor-irradiated Mo targets then used for extraction of (99m)Tc over a period of 2 wk, with 3 extractions on the same day. Estimates suggest that a center receiving 1.85 TBq (50 Ci) of (99)Mo once every 4 d can provide 1.48-3.33 TBq (40-90 Ci) of (99m)Tc daily. This model can use research reactors operating in the United States to supply current (99)Mo needs by applying natural (nat)Mo targets. (99)Mo production capacity can be enhanced by using (98)Mo-enriched targets. The proposed model reduces the loss of (99)Mo by decay and avoids proliferation as well as waste management issues associated with fission-produced (99)Mo.

Status of Tc-99m and 99Mo/99mTc generator production in Bangladesh

International Nuclear Information System (INIS)

Abedin, Md. Zainul; Haque, Md. Azizul; Ali, Md. Ramjan; Hossain, Md. Anwar; Razzaque, Md. Abdur; Yasmin, Lyzu; Waheed, M. Fatima; Akhter, Rabeya; Mondal, Rafiuddin

2007-01-01

Radioisotope Production Division (RIPD) produced instant technetium-99m by solvent extraction method for several years. On R and D basis, the division produced portable sterile Tc-99m sublimation generator by irradiating titanium molybdate in the reactor. The division produced (4/batch) from imported fission Mo-99 till June 2005. Since August 2005, as per demand of the government hospitals, the division have been producing 12-14 pieces of 15 GBq chromatographic 99m Tc-generators weekly by using the new generator production plant installed last year having online Mo-99 loading system with the of producing 50 generator per batch. Development of PZC and (n,γ) 99 Mo based generator holds potential in Bangladesh. (author)

Pharmaceutical grade sodium (99mTc) pertechnetate from 99Mo/99mTc-TCM-Autosolex generator

International Nuclear Information System (INIS)

Chattopadhyay, Sankha; Barua, Luna; Das, Sujata Saha

2014-01-01

Technetium-99m (T 1/2 = 6.02h; 140.51 keV (89%)) is the most useful radioisotope in diagnostic nuclear medicine. More than 80% of all diagnostic procedures done worldwide in nuclear medicine centre are performed with 99m Tc. Worldwide crisis of fission 99 Mo based generator in recent past had put the nuclear medicine fraternity in very harsh situation. In order to have an indigenous solution of this problem, we tried to develop a computer controlled semi automated 99 Mo/ 99m Tc generator using MEK solvent extraction technique, which utilizes abundantly available 99 Mo produced by (n,γ) reaction in BARC reactors. The aim of this work is to provide a more reliable, computer controlled module (TCM- AUTOSOLEX) for the recovery of pharmaceutical grade 99m Tc from low specific activity 99 Mo based on solvent extraction methodology

Topological Valley Transport in Two-dimensional Honeycomb Photonic Crystals.

Science.gov (United States)

Yang, Yuting; Jiang, Hua; Hang, Zhi Hong

2018-01-25

Two-dimensional photonic crystals, in analogy to AB/BA stacking bilayer graphene in electronic system, are studied. Inequivalent valleys in the momentum space for photons can be manipulated by simply engineering diameters of cylinders in a honeycomb lattice. The inequivalent valleys in photonic crystal are selectively excited by a designed optical chiral source and bulk valley polarizations are visualized. Unidirectional valley interface states are proved to exist on a domain wall connecting two photonic crystals with different valley Chern numbers. With the similar optical vortex index, interface states can couple with bulk valley polarizations and thus valley filter and valley coupler can be designed. Our simple dielectric PC scheme can help to exploit the valley degree of freedom for future optical devices.

Integration of environmental and spectral data for sunflower stress determination. [Red River Valley, Minnesota

Science.gov (United States)

Lillesand, T.; Seeley, M.

1983-01-01

Stress in sunflowers was assessed in western and northwestern Minnesota. Weekly ground observations (acquired in 1980 and 1981) were analyzed in concert with large scale aerial photography and concurrent LANDSAT data. Using multidate supervised and unsupervised classification procedures, it was found that all crops grown in association with sunflowers in the study area are spectrally separable from one another. Under conditions of extreme drought, severely stressed plants were differentiable from those not severely stressed, but between-crop separation was not possible. Initial regression analyses to estimate sunflower seed yield showed a sensitivity to environmental stress during the flowering and seed development stages. One of the most important biological factors related to sunflower production in the Red River Valley area was found to be the extent and severity of insect infestations.

Mechanical control over valley magnetotransport in strained graphene

Energy Technology Data Exchange (ETDEWEB)

Ma, Ning, E-mail: maning@stu.xjtu.edu.cn [Department of Physics, MOE Key Laboratory of Advanced Transducers and Intelligent Control System, Taiyuan University of Technology, Taiyuan 030024 (China); Department of Applied Physics, MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter, Xi' an Jiaotong University, Xi' an 710049 (China); Zhang, Shengli, E-mail: zhangsl@mail.xjtu.edu.cn [Department of Applied Physics, MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter, Xi' an Jiaotong University, Xi' an 710049 (China); Liu, Daqing, E-mail: liudq@cczu.edu.cn [School of Mathematics and Physics, Changzhou University, Changzhou 213164 (China)

2016-05-06

Recent experiments report that the graphene exhibits Landau levels (LLs) that form in the presence of a uniform strain pseudomagnetic field with magnitudes up to hundreds of tesla. We further reveal that the strain removes the valley degeneracy in LLs, and leads to a significant valley polarization with inversion symmetry broken. This accordingly gives rise to the well separated valley Hall plateaus and Shubnikov–de Haas oscillations. These effects are absent in strainless graphene, and can be used to generate and detect valley polarization by mechanical means, forming the basis for the new paradigm “valleytronics” applications. - Highlights: • We explore the mechanical strain effects on the valley magnetotransport in graphene. • We analytically derive the dc collisional and Hall conductivities under strain. • The strain removes the valley degeneracy in Landau levels. • The strain causes a significant valley polarization with inversion symmetry broken. • The strain leads to the well separated valley Hall and Shubnikov–de Haas effects.

Accuracy of 99Molybdenum assays in /sup 99m/Technetium solutions

International Nuclear Information System (INIS)

Williams, C.C.; Kereiakes, J.G.; Grossman, L.W.

1981-01-01

A study was performed to determine the accuracy of 99 Mo measurements using three commercial dose calibrators with their 99 Mo assay shields. One 99 Mo assay shield allowed excessive penetration by the lower energy /sup 99m/Tc photons, resulting in the calibrator's falsely high interpretation of the activity of 99 Mo present in the high-activity /sup 99m/Tc eluates. All three calibrators performed adequately with a National Bureau of Standards 99 Mo standard in equilibrium with /sup 99m/Tc. By using low-activity aliquots of 99 Mo and /sup 99m/Tc, a low-level linearity test was performed. Only one of the calibrators was found to reflect accurately the activity of 99 Mo present under all conditions tested

Characterization of source rocks and groundwater radioactivity at the Chihuahua valley

Energy Technology Data Exchange (ETDEWEB)

Renteria V, M.; Montero C, M.E.; Reyes C, M.; Herrera P, E.F.; Valenzuela H, M. [Centro de lnvestigacion en Materiales Avanzados, Miguel de Cervantes 120, 31109 Chihuahua, (Mexico); Rodriguez P, A. [World Wildlife Fund (WWF), Chihuahuan Desert Program, Coronado 1005, 31000 Chihuahua (Mexico); Manjon C, G.; Garcia T, R. [Universidad de Sevilla, Departamento de Fisica Aplicada 11, ETS Arquitectura, Av. Reina Mercedes 2, 41012 Sevilla, (Spain); Crespo, T. [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas (CIEMAT), Av. Complutense 22, 28040 Madrid, (Spain)]. e-mail: elena.montero@cimav.edu.mx

2007-07-01

As part of a scientific research project about alpha radioactivity in groundwater for human consumption at the Chihuahua City, the characterization of rock sources of radioactivity around de Chihuahua valley was developed. The radioactivity of groundwater and sediments was determined, too. The radioactivity of uranium- and thorium- series isotopes contained in rocks was obtained by high resolution gamma-ray spectroscopy. Some representative values are 50 Bq/kg for the mean value of Bi-214 activity, and 121.5 Bq/kg for the highest value at West of the city. The activity of sediments, extracted during wells perforation, was determined using a Nal(TI) detector. A non-reported before uranium ore was localized at the San Marcos range formation. Its outcrops are inside the Chihuahua-Sacramento valley basin and its activity characterization was performed. Unusually high specific uranium activities, determined by alpha spectrometry, were obtained in water, plants, sediments and fish extracted at locations close to outcrops of uranium minerals. The activity of water of the San Marcos dam reached 7.7 Bq/L. The activity of fish, trapped at San Marcos dam, is 0.99 Bq/kg. Conclusions about the contamination of groundwater at North of Chihuahua City were obtained. (Author)

Characterization of source rocks and groundwater radioactivity at the Chihuahua valley

International Nuclear Information System (INIS)

Renteria V, M.; Montero C, M.E.; Reyes C, M.; Herrera P, E.F.; Valenzuela H, M.; Rodriguez P, A.; Manjon C, G.; Garcia T, R.; Crespo, T.

2007-01-01

As part of a scientific research project about alpha radioactivity in groundwater for human consumption at the Chihuahua City, the characterization of rock sources of radioactivity around de Chihuahua valley was developed. The radioactivity of groundwater and sediments was determined, too. The radioactivity of uranium- and thorium- series isotopes contained in rocks was obtained by high resolution gamma-ray spectroscopy. Some representative values are 50 Bq/kg for the mean value of Bi-214 activity, and 121.5 Bq/kg for the highest value at West of the city. The activity of sediments, extracted during wells perforation, was determined using a Nal(TI) detector. A non-reported before uranium ore was localized at the San Marcos range formation. Its outcrops are inside the Chihuahua-Sacramento valley basin and its activity characterization was performed. Unusually high specific uranium activities, determined by alpha spectrometry, were obtained in water, plants, sediments and fish extracted at locations close to outcrops of uranium minerals. The activity of water of the San Marcos dam reached 7.7 Bq/L. The activity of fish, trapped at San Marcos dam, is 0.99 Bq/kg. Conclusions about the contamination of groundwater at North of Chihuahua City were obtained. (Author)

Annual report, 1980

International Nuclear Information System (INIS)

1980-01-01

Operations of Ontario Hydro, one of North America's largest utilities, for the year 1980 are described. A new energy-use strategy was evolved during 1980 which included maximizing use of electricity generated from indigenous sources to substitute for imported fossil fuels. Due to the consistently outstanding performance of the utility's nuclear plants at Pickering and Bruce, nuclear power supplied 34 percent of the total energy generated, up three percent from 1979. This is second only to hyraulic generation. Ontario Hydro's reactors, four of which led the world's power reactors with capacities exceeding 500 MW in overall capacity factor, continued to provide reliable generation. Ontario Hydro is a publicly-owned financially self-supporting utility. During 1980 steps were taken to reduce the difference in rates between rural and urban customers. Average rate increases to be implemented in January 1981 were 9.3 percent for municipal utilities, 9.6 percent to direct industrial customers, and 11.2 percent for direct rural customers. The average revenue from residential users was $0.0364 per kwh. Revenue was $2.8 billion on assets of $15.6 billion. (O.T.)

Welcome to My House: African American and European American Students' Responses to Virginia Hamilton's "House of Dies Drear."

Science.gov (United States)

Spears-Bunton, Linda A.

1990-01-01

Addresses the relationship between reader response and culture. Presents portraits of a teacher and her Black students and White students as they studied a series of African American literary texts, including Virginia Hamilton's "House of Dies Drear" (1968). The reading of this text marked a turning point for the teacher and students.…

Bibliography of literature pertaining to Long Valley Caldera and associated volcanic fields

Science.gov (United States)

Ewert, John W.; Harpel, Christopher J.; Brooks, Suzanna K.; Marcaida, Mae

2011-01-01

On May 25-27, 1980, Long Valley caldera was rocked by four M=6 earthquakes that heralded the onset of a wave of seismic activity within the caldera which has continued through the present. Unrest has taken the form of seismic swarms, uplift of the resurgent dome, and areas of vegetation killed by increased CO2 emissions, all interpreted as resulting from magma injection into different levels beneath the caldera, as well as beneath Mammoth Mountain along the southwest rim of the caldera. Continuing economic development in the Mammoth Lakes area has swelled the local population, increasing the risk to people and property if an eruption were to occur. The U.S. Geological Survey (USGS) has been monitoring geophysical activity in the Long Valley area since the mid-1970s and continues to track the unrest in real time with a sophisticated network of geophysical sensors. Hazards information obtained by this monitoring is provided to local, State, and Federal officials and to the public through the Long Valley Observatory. The Long Valley area also was scientifically important before the onset of current unrest. Lying at the eastern foot of the Sierra Nevada, the deposits from this active volcanic system have provided fertile ground for research into Neogene tectonics, Quaternary geology and geomorphology, regional stratigraphy, and volcanology. In the early 1970s, intensive studies of the area began through the USGS Geothermal Investigations Program, owing to the presence of a large young silicic volcanic system. The paroxysmal eruption of Long Valley caldera about 760,000 years ago produced the Bishop Tuff and associated Bishop ash. The Bishop Tuff is a well-preserved ignimbrite deposit that has continued to provide new and developing insights into the dynamics of ignimbrite-forming eruptions. Another extremely important aspect of the Bishop Tuff is that it is the oldest known normally magnetized unit of the Brunhes Chron. Thus, the age of the Bishop Tuff is used to

The impact of Mediterranean oscillations on periodicity and trend of temperature in the valley of the Nisava River: A fourier and wavelet approach

Directory of Open Access Journals (Sweden)

Martić-Bursać Nataša M.

2017-01-01

Full Text Available Periodicity of temperature on three stations in the Nisava River valley in period 1949-2014, has been analyzed by means of Fourier and wavelet transforms. Combined periodogram based on fast Fourier transform shows considerable similarity among individual series and identifies significant periods on 2.2, 2.7, 3.3, 5, 6-7, and 8.2 years in all datasets. Wavelet coherence analysis connects strongest 6-7 years spectral component to Mediterranean oscillation, starting in 1980s. Combined periodogram of Mediterranean oscillation index reveals 6-7 years spectral component as a dominant mode in period 1949-2014. Wavelet power spectra and partial combined periodograms show absence of 6-7 years component before 1975, after which this component becomes dominant in the spectrum. Consistency between alternation in temperature trend in the Nisava River valley and change in periodicity of Mediterranean oscillation was found. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. OI176008

Regional climate change trends and uncertainty analysis using extreme indices: A case study of Hamilton, Canada

OpenAIRE

Razavi, Tara; Switzman, Harris; Arain, Altaf; Coulibaly, Paulin

2016-01-01

This study aims to provide a deeper understanding of the level of uncertainty associated with the development of extreme weather frequency and intensity indices at the local scale. Several different global climate models, downscaling methods, and emission scenarios were used to develop extreme temperature and precipitation indices at the local scale in the Hamilton region, Ontario, Canada. Uncertainty associated with historical and future trends in extreme indices and future climate projectio...

Housing provision in the Kathmandu Valley: Public agency and private sector initiation

Directory of Open Access Journals (Sweden)

Bijaya K. Shrestha

2010-01-01

Full Text Available The haphazard growth of settlements in the Kathmandu Valley is the result of rapid urbanisation, growing poverty, the high cost of land and construction, and dependence on the traditional practice of owner-built housing. This growth has resulted in huge housing deficits and poor home conditions. The government’s implementation of the site and services programme as well as land-pooling projects in the 1970s and 1980s benefitted local landowners, but private-sector developments in the 1990s and 2000s were only accessible to upper-middle and high-income groups. This has forced the urban poor and economically disadvantaged groups to live in slum and squatter developments. Planned development organisation has been weak in terms of physical layout, the creation of socialisation opportunities and a sense of community, and in achieving a desirable population density. The existing legal and institutional framework is inadequate and ineffective for addressing these issues. To fill the gap between the efforts of the public and private sectors and meet the high demands for housing in the valley, clear-cut policies and planning are required. This must be done in order to link housing supply with demand and to ensure the participation of various public and private-sector agencies in land-development and housing projects that will incorporate the urban poor. Local municipalities should also be equipped for managing local resources, coordinating the agencies involved and monitoring development.

On the Connection between the Hamilton-Jacobi-Bellman and the Fokker-Planck Control Frameworks

KAUST Repository

Annunziato, Mario

2014-09-01

In the framework of stochastic processes, the connection between the dynamic programming scheme given by the Hamilton-Jacobi-Bellman equation and a recently proposed control approach based on the Fokker-Planck equation is discussed. Under appropriate assumptions it is shown that the two strategies are equivalent in the case of expected cost functionals, while the FokkerPlanck formalism allows considering a larger class of objectives. To illustrate the connection between the two control strategies, the cases of an Itō stochastic process and of a piecewise-deterministic process are considered.

Probabilistic formulation of estimation problems for a class of Hamilton-Jacobi equations

KAUST Repository

Hofleitner, Aude; Claudel, Christian G.; Bayen, Alexandre M.

2012-01-01

This article presents a method for deriving the probability distribution of the solution to a Hamilton-Jacobi partial differential equation for which the value conditions are random. The derivations lead to analytical or semi-analytical expressions of the probability distribution function at any point in the domain in which the solution is defined. The characterization of the distribution of the solution at any point is a first step towards the estimation of the parameters defining the random value conditions. This work has important applications for estimation in flow networks in which value conditions are noisy. In particular, we illustrate our derivations on a road segment with random capacity reductions. © 2012 IEEE.

Code Red: Explaining Average Age of Death in the City of Hamilton

Directory of Open Access Journals (Sweden)

Patrick F. DeLuca

2015-11-01

Full Text Available The aim of this study is to identify the underlying factors that explain the average age of death in the City of Hamilton, Ontario, Canada, as identified in the Code Red Series of articles that were published in the city's local newspaper in 2010. Using a combination of data from the Canadian Census, the Government of Ontario and the Canadian Institute for Health Information, factor analysis was performed yielding three factors relating to poverty, working class, and health and aging. In a regression analysis these factors account for 42% of the total variability in the average ages of death observed at the census tract level of geography within the city.

Probabilistic formulation of estimation problems for a class of Hamilton-Jacobi equations

KAUST Repository

Hofleitner, Aude

2012-12-01

This article presents a method for deriving the probability distribution of the solution to a Hamilton-Jacobi partial differential equation for which the value conditions are random. The derivations lead to analytical or semi-analytical expressions of the probability distribution function at any point in the domain in which the solution is defined. The characterization of the distribution of the solution at any point is a first step towards the estimation of the parameters defining the random value conditions. This work has important applications for estimation in flow networks in which value conditions are noisy. In particular, we illustrate our derivations on a road segment with random capacity reductions. © 2012 IEEE.

Study of methodologies for quality control of 99Mo used in 99Mo/99mTc generators

International Nuclear Information System (INIS)

Said, Daphne de Souza

2016-01-01

99m Tc is the most used radionuclide in nuclear medicine. In Brazil, the 99 Mo/ 99m Tc generators are exclusively produced by Radiopharmacy Center at IPEN-CNEN/ SP, by importing 99 Mo from different suppliers. 99 Mo (t 1/2 = 66 h) is a fission product of 235 U and it can have radionuclidic impurities that are prejudicial for human health. For safe use of generators, it is necessary to perform the evaluation of 99 Mo by quality control tests in order to assess if 99 Mo complies with the specifications. The European Pharmacopoeia (EP) presents a monograph for evaluation of the quality of the [ 99 Mo] solution as sodium molybdate,that is used as raw material for 99 Mo/ 99m Tc generators production, including specification parameters (identification, radiochemical purity and radionuclidic purity), analysis methods and limits. However, it has been observed difficulties on the execution and implementation of these methods by the generators producers, with a few literature about this subject, probably due to complexity of the proposed methods. In this work, many quality control parameters of 99 Mo described in the EP monograph were evaluated. Separation methods for 99M o from its radionuclidic impurities by solid phase extraction (SPE) and TLC were studied. After SPE separation, the quantification of metals by ICP-OES to evaluate the percentage of retention of Mo and the percentage of recovery of Ru, Te and Sr using different types of cartridges were proposed, replacing radiotracers use. It was observed that the specific type of SPE cartridge recommended by the EP for separation of 99 Mo presented low recoveries for Ru, compared to other available anion exchange SPE cartridges. 99 Mo samples from different worldwide suppliers were analyzed. It was observed that quantification of 103 Ru in 99 Mo samples with decay time higher than 4 weeks is possible. An alternative method for separation of 131 I from 99 Mo showed promising results by TLC. The quantification of beta and

The geochemistry of groundwater resources in the Jordan Valley: The impact of the Rift Valley brines

Science.gov (United States)

Farber, E.; Vengosh, A.; Gavrieli, I.; Marie, Amarisa; Bullen, T.D.; Mayer, B.; Polak, A.; Shavit, U.

2007-01-01

The chemical composition of groundwater in the Jordan Valley, along the section between the Sea of Galilee and the Dead Sea, is investigated in order to evaluate the origin of the groundwater resources and, in particular, to elucidate the role of deep brines on the chemical composition of the regional groundwater resources in the Jordan Valley. Samples were collected from shallow groundwater in research boreholes on two sites in the northern and southern parts of the Jordan Valley, adjacent to the Jordan River. Data is also compiled from previous published studies. Geochemical data (e.g., Br/Cl, Na/Cl and SO4/Cl ratios) and B, O, Sr and S isotopic compositions are used to define groundwater groups, to map their distribution in the Jordan valley, and to evaluate their origin. The combined geochemical tools enabled the delineation of three major sources of solutes that differentially affect the quality of groundwater in the Jordan Valley: (1) flow and mixing with hypersaline brines with high Br/Cl (>2 ?? 10-3) and low Na/Cl (shallow saline groundwaters influenced by brine mixing exhibit a north-south variation in their Br/Cl and Na/Cl ratios. This chemical trend was observed also in hypersaline brines in the Jordan valley, which suggests a local mixing process between the water bodies. ?? 2007 Elsevier Ltd. All rights reserved.

Current status of production and supply of molybdenum-99 and 99Mo/99mTc generators in Indonesia

International Nuclear Information System (INIS)

Mutalib, A.

2003-01-01

Production of high-specific activity molybdenum-99 and 99 Mo/ 99m Tc Generators in Indonesia commenced when a new production facility supported by the presence of a 30 MW multipurpose reactor (RSG-GAS) was established in Serpong in 1990. This report describes the current production and supply of molybdenum-99m devoted mainly to fulfill the domestic demands in supplying 99 Mo/ 99m Tc Generators. Recent development on the use of LEU (Low Enriched Uranium) targets for replacing current HEU (High Enriched Uranium) targets in the production of 99 Mo will be reviewed briefly. (author)

Energy Balance of the Santa Catarina State - Series 1980 -1996; Balanco energetico do Estado de Santa Catarina - Serie 1980-1996

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-07-01

This energy balance of the Santa Catarina State presents the following main topics that can be outstanding: economic aspects; supply and demand of energy by source 1980-1996; energy consumption by sector 1980/1996; energy interchange; and balance of the transformation centers 1980/1996.

Measurement of Mo-99 column activity in the evaluation of Mo-99/Tc-99m generator

International Nuclear Information System (INIS)

Kuster, Z.

1994-01-01

In order to calculate the real elution efficiency of Mo-99/Tc-99m generator the Mo-99 content on the column has to be previously determined. As found in this work, the external measurement of Mo-99-column activity by means of Geiger-Mueller counter is a simple, fast and reliable method. Generally, Mo-99-column is placed slightly out of the center of the generator; therefore the externally measured flux of photons (φ) is an angular-dependent function. If the thickness of the lead container is radially uniform, the flux measured at some distance from the generator (which is rotated in 2π/3 steps) is given by the equation φ = A (1 + Bcos (α-2π(i - 2)/3)) -1 , i=1,2 or 3 (Eq.1) where A is a numerical constant depending on the Mo-99-column activity, B is a numerical constant depending on the Mo-99- column position within the lead container, the angle α depends on the initial orientation of the generator. A total of 20 generator were studied. The measured Mo-99-column activities (Capintec dose calibrator) were in the range 13.1- 35.11 GBq. Contrary to the findings of Vinberg and Kristensen (Eur J Nucl Med 1/1976(219), values of A (Eq. 1) are in good correlation (r 2 =0.9794) with the measured Mo-99-column activities. (author)

Evaluation of process alternatives for solidification of the West Valley high-level liquid wastes

International Nuclear Information System (INIS)

Holton, L.K.; Larson, D.E.

1982-01-01

The Department of Energy (DOE) established the West Valley Solidification Project (WVSP) in 1980. The project purpose is to demonstrate removal and solidification of the high-level liquid wastes (HLLW) presently stored in tanks at the Western New York Nuclear Service Center (WNYNSC), West Valley, New York. As part of this effort, the Pacific Northwest Laboratory (PNL) conducted a study to evaluate process alternatives for solidifcation of the WNYNSC wastes. Two process approaches for waste handling before solidification, together with solidification processes for four terminal and four interim waste forms, were considered. The first waste-handling approach, designated the salt/sludge separation process, involves separating the bulk of the nonradioactive nuclear waste constituents from the radioactive waste constituents, and the second waste-handling approach, designated the combined-waste process, involves no waste segregation prior to solidification. The processes were evaluated on the bases of their (1) readiness for plant startup by 1987, (2) relative technical merits, and (3) process cost. The study has shown that, based on these criteria, the salt/sludge separation process with a borosilicate glass waste form is preferred when producing a terminal waste form. It was also concluded that if an interim waste form is to be used, the preferred approach would be the combined waste process with a fused-salt waste form

Title: Long Valley Caldera 2003 through 2012: Overview of low level unrest in the last decade Authors: Stuart Wilkinson, David Hill, Michael Lisowski, Deborah Bergfeld, Margaret Mangan

Science.gov (United States)

Wilkinson, S. K.; Hill, D. P.; Lisowski, M.; Bergfeld, D.; Mangan, M.

2012-12-01

Long Valley Caldera is located in central California along the eastern escarpment of the Sierra Nevada and at the western edge of the Basin and Range. The caldera formed 0.76 Ma ago during the eruption of 600 cubic kilometers the Bishop Tuff that resulted in the collapse of the partially evacuated magma chamber. Since at least late 1978, Long Valley Caldera has experienced recurring earthquake swarms and ground uplift, suggesting future eruptions are possible. Unrest in Long Valley Caldera during the 1980s to early 2000s is well documented in the literature. Episodes of inflation centered on the resurgent dome in the western part of the caldera occurred in 1979-1980, 1983, 1989-1990, 1997-1998, and 2002-2003, accumulating ~ 80 cm of uplift. Earthquakes of M ≥ 3.0 were numerous in the caldera and in the Sierra Nevada block to the south of the caldera from 1980 through 1983 (800 events including four M~ 6 earthquakes in 1980); in the caldera from 1997 through mid-1998 (150 events); and in the Sierra Nevada block from mid-1998 through 1999 (~160 events) and more modestly from 2002 through 2003 (7 events). In this presentation, we summarize the low-levels of caldera unrest during the last decade. The number of earthquakes in Sierra Nevada block and the caldera has gradually diminished over the last decade. Fifty Sierra Nevada earthquakes had magnitudes 3.0≤M≤4.6. In the caldera, only six earthquakes had magnitudes 3.0≤M≤3.8. A three-month swarm of minor earthquakes (235 events with 0.5≤M≤3.8; most below 2.0) occurred in the caldera in mid-2010. Analysis of continuous GPS data over the last year shows an inflationary pattern within the caldera centered on the resurgent dome, with a maximum uplift rate of ~ 2-3 cm/yr. The rate of deformation is comparable to that of 2002-2003, and well below ~ 70 cm/yr rates observed during the peak of inflation in the late 1990s. Steaming ground and diffuse CO2 discharge has long been a feature of Long Valley Caldera

Long Valley Caldera 2003 through 2014: overview of low level unrest in the past decade

Science.gov (United States)

Wilkinson, Stuart K.; Hill, David P.; Langbein, John O.; Lisowski, Michael; Mangan, Margaret T.

2014-01-01

Long Valley Caldera is located in California along the eastern escarpment of the Sierra Nevada Range. The caldera formed about 760,000 years ago as the eruption of 600 km3 of rhyolite magma (Bishop Tuff) resulted in collapse of the partially evacuated magma chamber. Resurgent doming in the central part of the caldera occurred shortly afterwards, and the most recent eruptions inside the caldera occurred about 50,000 years ago. The caldera remains thermally active, with many hot springs and fumaroles, and has had significant deformation and seismicity since at least 1978. Periods of intense unrest in the 1980s to early 2000s are well documented in the literature (Hill and others, 2002; Ewert and others, 2010). In this poster, we extend the timeline forward, documenting seismicity and deformation over the past decade.

27 CFR 9.27 - Lime Kiln Valley.

Science.gov (United States)

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Lime Kiln Valley. 9.27... OF THE TREASURY LIQUORS AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.27 Lime Kiln Valley. (a) Name. The name of the viticultural area described in this section is “Lime Kiln Valley...

The effectiveness of acupuncture as a treatment for tinnitus: a randomized controlled trial using 99mTc-ECD SPECT

International Nuclear Information System (INIS)

Laureano, Maura Regina; Braga Neto, Pedro; Ligia Sanchez, Maura; Cogo Moreira, Hugo; Ribeiro de Almeida, Roberta; Parolin Jackowski, Andrea; Onishi, Ektor Tsuneo; Affonseca Bressan, Rodrigo; Batista, Ilza Rosa; Alves Reis, Marilia; Vieira Castiglioni, Mario Luiz; Vargas Garcia, Michele; Neves de Andrade, Adriana; Jara Garrido, Griselda

2016-01-01

Investigate the effect of acupuncture on brain perfusion using ethyl cysteinate dimer single-photon emission computed tomography ( 99m Tc-ECD SPECT) in patients with tinnitus. This randomized, single-blind, sham-control study examined patients (18-60 years old) with normal hearing and chronic, idiopathic, continuous tinnitus. Fifty-seven subjects were randomly assigned to true (n = 30) or sham (n = 27) acupuncture (ACP); 99m Tc-ECD SPECT examinations were performed before and after 12 twice-weekly ACP sessions. Secondary outcomes included changes in the Tinnitus Handicap Inventory (THI), Visual Analog Scale (VAS), Hamilton Anxiety Scale (HAS) and Beck Depression Inventory (BDI). Imaging data were analysed using Statistical Parametric Mapping (SPM8) software. Regression models were used to examine secondary outcomes via two paradigms: intention-to-treat (ITT; where multiple imputations were conducted because of study attrition) and complete cases. No between-group brain perfusion differences were observed. However, a significant improvement in THI scores was observed at the end of true ACP treatment for all domains (all p values < 0.01) except the catastrophic scale. ACP might reduce the effects of tinnitus on daily life; however, additional studies should be conducted to verify the effects of ACP on the neural architecture and brain function of tinnitus patients. (orig.)

A case study: the initiative to improve RN scheduling at Hamilton Health Sciences.

Science.gov (United States)

Wallace, Laurel-Anne; Pierson, Sharon

2008-01-01

In 2003, Hamilton Health Sciences embarked on an initiative to improve and standardize nursing schedules and scheduling practices. The scheduling project was one of several initiatives undertaken by a corporate-wide Nursing Resource Group established to enhance the work environment and patient care and to ensure appropriate utilization of nursing resources across the organization's five hospitals. This article focuses on major activities undertaken in the scheduling initiative. The step-by-step approach described, plus examples of the scheduling resources developed and samples of extended-tour schedules, will all provide insight, potential strategies and practical help for nursing administrators, human resources (HR) personnel and others interested in improving nurse scheduling.

A valley-filtering switch based on strained graphene.

Science.gov (United States)

Zhai, Feng; Ma, Yanling; Zhang, Ying-Tao

2011-09-28

We investigate valley-dependent transport through a graphene sheet modulated by both the substrate strain and the fringe field of two parallel ferromagnetic metal (FM) stripes. When the magnetizations of the two FM stripes are switched from the parallel to the antiparallel alignment, the total conductance, valley polarization and valley conductance excess change greatly over a wide range of Fermi energy, which results from the dependence of the valley-related transmission suppression on the polarity configuration of inhomogeneous magnetic fields. Thus the proposed structure exhibits the significant features of a valley-filtering switch and a magnetoresistance device.

A valley-filtering switch based on strained graphene

International Nuclear Information System (INIS)

Zhai Feng; Ma Yanling; Zhang Yingtao

2011-01-01

We investigate valley-dependent transport through a graphene sheet modulated by both the substrate strain and the fringe field of two parallel ferromagnetic metal (FM) stripes. When the magnetizations of the two FM stripes are switched from the parallel to the antiparallel alignment, the total conductance, valley polarization and valley conductance excess change greatly over a wide range of Fermi energy, which results from the dependence of the valley-related transmission suppression on the polarity configuration of inhomogeneous magnetic fields. Thus the proposed structure exhibits the significant features of a valley-filtering switch and a magnetoresistance device. (paper)

Electrical valley filtering in transition metal dichalcogenides

Science.gov (United States)

Hsieh, Tzu-Chi; Chou, Mei-Yin; Wu, Yu-Shu

2018-03-01

This work investigates the feasibility of electrical valley filtering for holes in transition metal dichalcogenides. We look specifically into the scheme that utilizes a potential barrier to produce valley-dependent tunneling rates, and perform the study with both a k .p -based analytic method and a recursive Green's function-based numerical method. The study yields the transmission coefficient as a function of incident energy and transverse wave vector, for holes going through lateral quantum barriers oriented in either armchair or zigzag directions, in both homogeneous and heterogeneous systems. The main findings are the following: (1) The tunneling current valley polarization increases with increasing barrier width or height; (2) both the valley-orbit interaction and band structure warping contribute to valley-dependent tunneling, with the former contribution being manifest in structures with asymmetric potential barriers, and the latter being orientation dependent and reaching maximum for transmission in the armchair direction; and (3) for transmission ˜0.1 , a tunneling current valley polarization of the order of 10 % can be achieved.

Quality assurance of Mo-99/Tc-99m radionuclide generators

Science.gov (United States)

Uzunov, Nikolay; Yordanova, Galina; Salim, Seniha; Stancheva, Natalya; Mineva, Vanya; Meléndez-Alafort, Laura; Rosato, Antonio

2018-03-01

Gamma-ray spectrometry analyses of the radionuclide content of eluate from two Mo-99/Tc-99m radionuclide generators POLTECHNET have been performed. The relative activities of 99Mo 103Ru and 131I radioisotopes with respect to the activity of 99mTc at different time intervals after the primary pertechnetate elution of the generators have been analyzed. The relative activities of the isotopes were determined and compared to the radionuclidic purity requirements for 99mTc.

Polyfluoroalkyl substance exposure in the Mid-Ohio River Valley, 1991-2012.

Science.gov (United States)

Herrick, Robert L; Buckholz, Jeanette; Biro, Frank M; Calafat, Antonia M; Ye, Xiaoyun; Xie, Changchun; Pinney, Susan M

2017-09-01

Industrial discharges of perfluorooctanoic acid (PFOA) to the Ohio River, contaminating water systems near Parkersburg, WV, were previously associated with nearby residents' serum PFOA concentrations above US general population medians. Ohio River PFOA concentrations downstream are elevated, suggesting Mid-Ohio River Valley residents are exposed through drinking water. Quantify PFOA and 10 other per- and polyfluoroalkyl substances (PFAS) in Mid-Ohio River Valley resident sera collected between 1991 and 2013 and determine whether the Ohio River and Ohio River Aquifer are exposure sources. We measured eleven PFAS in 1608 sera from 931 participants. Serum PFOA concentration and water source associations were assessed using linear mixed-effects models. We estimated between-sample serum PFOA using one-compartment pharmacokinetics for participants with multiple samples. In serum samples collected as early as 1991, PFOA (median = 7.6 ng/mL) was detected in 99.9% of sera; 47% had concentrations greater than US population 95th percentiles. Five other PFAS were detected in greater than 82% of samples; median other PFAS concentrations were similar to the US general population. Serum PFOA was significantly associated with water source, sampling year, age at sampling, tap water consumption, pregnancy, gravidity and breastfeeding. Serum PFOA was 40-60% lower with granular activated carbon (GAC) use. Repeated measurements and pharmacokinetics suggest serum PFOA peaked 2000-2006 for participants using water without GAC treatment; where GAC was used, serum PFOA concentrations decreased from 1991 to 2012. Mid-Ohio River Valley residents appear to have PFOA, but not other PFAS, serum concentrations above US population levels. Drinking water from the Ohio River and Ohio River Aquifer, primarily contaminated by industrial discharges 209-666 km upstream, is likely the primary exposure source. GAC treatment of drinking water mitigates, but does not eliminate, PFOA exposure. Copyright

EPA Region 1 - Valley Depth in Meters

Science.gov (United States)

Raster of the Depth in meters of EPA-delimited Valleys in Region 1.Valleys (areas that are lower than their neighbors) were extracted from a Digital Elevation Model (USGS, 30m) by finding the local average elevation, subtracting the actual elevation from the average, and selecting areas where the actual elevation was below the average. The landscape was sampled at seven scales (circles of 1, 2, 4, 7, 11, 16, and 22 km radius) to take into account the diversity of valley shapes and sizes. Areas selected in at least four scales were designated as valleys.

Molybdenum-99/technetium-99M generators

International Nuclear Information System (INIS)

Morcos, N.A.; Bruno, G.A.; Haney, T.A.

1981-01-01

A 99 Mo/sup(99m)Tc generator is described which has an alumina support medium consisting of multiple beds of controlled pH and in which no bed has a pH value higher than the bed preceding it. It is claimed that by using this method low yield problems of such generators can be mitigated. (U.K.)

Generators of 99Mo-99mTc

International Nuclear Information System (INIS)

Robles, A.M.

1994-01-01

Between the radioisotopes family pairs we find the 99 Molibdenum - 99m technetium pairs. Such as isotope production,decay and chemical toxic, humid and dry generators,radiation protection handling practice and blinding had been sudied in this work.Tabs

Lie-admissible structure of Hamilton's original equations with external terms

International Nuclear Information System (INIS)

Santilli, R.M.

1991-09-01

As a necessary additional step in preparation of our operator studies of closed nonhamiltonian systems, in this note we consider the algebraic structure of the original equations proposed by Lagrange and Hamilton, those with external terms representing precisely the contact nonpotential forces of the interior dynamical problem. We show that the brackets of the theory violate the conditions to characterize any algebra. Nevertheless, when properly written, they characterize a covering of the Lie-isotopic algebras called Lie-admissible algebras. It is indicated that a similar occurrence exists for conventional operator treatments, e.g. for nonconservative nuclear cases characterized by nonhermitean Hamiltonians. This occurrence then prevents a rigorous treatment of basic notions, such as that of angular momentum and spin spin, which are centrally dependent on the existence of a consistent algebraic structure. The emergence of the Lie-admissible algebras is therefore expected to be unavoidable for any rigorous operator treatment of open systems with nonlinear, nonlocal and nonhamiltonian external forces. (author). 14 refs, 1 fig

Preliminary hydrogeologic assessment near the boundary of the Antelope Valley and El Mirage Valley groundwater basins, California

Science.gov (United States)

Stamos, Christina L.; Christensen, Allen H.; Langenheim, Victoria

2017-07-19

The increasing demands on groundwater for water supply in desert areas in California and the western United States have resulted in the need to better understand groundwater sources, availability, and sustainability. This is true for a 650-square-mile area that encompasses the Antelope Valley, El Mirage Valley, and Upper Mojave River Valley groundwater basins, about 50 miles northeast of Los Angeles, California, in the western part of the Mojave Desert. These basins have been adjudicated to ensure that groundwater rights are allocated according to legal judgments. In an effort to assess if the boundary between the Antelope Valley and El Mirage Valley groundwater basins could be better defined, the U.S. Geological Survey began a cooperative study in 2014 with the Mojave Water Agency to better understand the hydrogeology in the area and investigate potential controls on groundwater flow and availability, including basement topography.Recharge is sporadic and primarily from small ephemeral washes and streams that originate in the San Gabriel Mountains to the south; estimates range from about 400 to 1,940 acre-feet per year. Lateral underflow from adjacent basins has been considered minor in previous studies; underflow from the Antelope Valley to the El Mirage Valley groundwater basin has been estimated to be between 100 and 1,900 acre-feet per year. Groundwater discharge is primarily from pumping, mostly by municipal supply wells. Between October 2013 and September 2014, the municipal pumpage in the Antelope Valley and El Mirage Valley groundwater basins was reported to be about 800 and 2,080 acre-feet, respectively.This study was motivated by the results from a previously completed regional gravity study, which suggested a northeast-trending subsurface basement ridge and saddle approximately 3.5 miles west of the boundary between the Antelope Valley and El Mirage Valley groundwater basins that might influence groundwater flow. To better define potential basement

Optically initialized robust valley-polarized holes in monolayer WSe2

KAUST Repository

Hsu, Wei-Ting

2015-11-25

A robust valley polarization is a key prerequisite for exploiting valley pseudospin to carry information in next-generation electronics and optoelectronics. Although monolayer transition metal dichalcogenides with inherent spin–valley coupling offer a unique platform to develop such valleytronic devices, the anticipated long-lived valley pseudospin has not been observed yet. Here we demonstrate that robust valley-polarized holes in monolayer WSe2 can be initialized by optical pumping. Using time-resolved Kerr rotation spectroscopy, we observe a long-lived valley polarization for positive trion with a lifetime approaching 1 ns at low temperatures, which is much longer than the trion recombination lifetime (~10–20 ps). The long-lived valley polarization arises from the transfer of valley pseudospin from photocarriers to resident holes in a specific valley. The optically initialized valley pseudospin of holes remains robust even at room temperature, which opens up the possibility to realize room-temperature valleytronics based on transition metal dichalcogenides.

Development of 99Mo/99mTc Generator System for Production of Medical Radionuclide 99mTc using a Neutron-activated 99Mo and Zirconium Based Material (ZBM as its Adsorbent

Directory of Open Access Journals (Sweden)

I. Saptiama

2016-12-01

Full Text Available Molybdenum produced from fission of U-235 is the most desirable precursor for 99Mo/99mTc generator system as it is non-carrier added and has high specific activity. However, in the last decade there has been short supply of 99Mo due to several constrains. Therefore, there have been many works performed for development of 99Mo/99mTc generator system using 99Mo which is not produced from either LEU or HEU. This report deals with development of 99Mo/99mTc generator system where zirconium-based material (ZBM is used as adsorbent of neutron-activated 99Mo. The system was prepared by firstly irradiating natural Mo in the G. A. Siwabessy reactor to produce neutron-activated 99Mo. The target was dissolved in NaOH 4N and then neutralized with 12 M HCl. The 99Mo solution was then mixed with a certain amount of ZBM followed by heating at 90°C for three hours to allow the 99Mo adsorbed on ZBM. The 99Mo-ZBM (9.36 GBq of 99Mo was Mo/ 4.2 g ZBM was packed on a fritz-glass column. This column was then fitted serially with an alumina column for trapping 99Mo breakthrough. The columns were then eluted daily with saline solution for up to one week. The yield of 99mTc was found to be between 53.7 – 74% (n= 5. All 99mTc eluates were clear solutions with pH of 5. Breakthrough of 99Mo in 99mTc eluates was found to be 0.031 ± 0.019 μCi 99Mo/ mCi 99mTc (n= 5 which was less than the maximum activity of 99Mo allowed in 99mTc solution ( 99%. Radiolabeling of this 99mTc towards methylene diphosphonate (MDP kit gave a radiolabelling efficiency of 99%. In summary, a new 99Mo/99mTc generator system that used neutron-activated 99Mo and ZBM as its adsorbent has been successfully prepared. The 99mTc produced from this new 99Mo/99mTc generator system attained the quality of 99mTc required for medical purposes.

Hamilton-Jacobi approach for first order actions and theories with higher derivatives

International Nuclear Information System (INIS)

Bertin, M.C.; Pimentel, B.M.; Pompeia, P.J.

2008-01-01

In this work, we analyze systems described by Lagrangians with higher order derivatives in the context of the Hamilton-Jacobi formalism for first order actions. Two different approaches are studied here: the first one is analogous to the description of theories with higher derivatives in the hamiltonian formalism according to [D.M. Gitman, S.L. Lyakhovich, I.V. Tyutin, Soviet Phys. J. 26 (1983) 730; D.M. Gitman, I.V. Tyutin, Quantization of Fields with Constraints, Springer-Verlag, New York, Berlin, 1990] the second treats the case where degenerate coordinate are present, in an analogy to reference [D.M. Gitman, I.V. Tyutin, Nucl. Phys. B 630 (2002) 509]. Several examples are analyzed where a comparison between both approaches is made

Valley-orbit hybrid states in Si quantum dots

Science.gov (United States)

Gamble, John; Friesen, Mark; Coppersmith, S. N.

2013-03-01

The conduction band for electrons in layered Si nanostructures oriented along (001) has two low-lying valleys. Most theoretical treatments assume that these valleys are decoupled from the long-wavelength physics of electron confinement. In this work, we show that even a minimal amount of disorder (a single atomic step at the quantum well interface) is sufficient to mix valley states and electron orbitals, causing a significant distortion of the long-wavelength electron envelope. For physically realistic electric fields and dot sizes, this valley-orbit coupling impacts all electronic states in Si quantum dots, implying that one must always consider valley-orbit hybrid states, rather than distinct valley and orbital degrees of freedom. We discuss the ramifications of our results on silicon quantum dot qubits. This work was supported in part by ARO (W911NF-08-1-0482) and NSF (DMR-0805045).

Oil demand in North America: 1980-2020

International Nuclear Information System (INIS)

Ghouri, S.S.

2001-01-01

This paper first analyses price and income elasticity of oil demand in the United States, Canada and Mexico for the period 1980-99. Economic activity is the main driving force that influences oil consumption in each country. Changes in oil consumption generally lagged by a few years before the full impact of changes in oil prices was realized. Consumers in the short run are constrained by technological and other barriers and, therefore, less sensitive to changes in oil prices; however, they are more responsive in the long run - though response is still inelastic. The use of advanced technology facilitated these countries to use less oil over time. The paper then looks at demand over the next 20 years. The best-fitting model predicts that, by the end of 2020 (reference case), the USA, Canada and Mexico will respectively consume 24,900, 2,596 and 2,321 thousand barrels daily, compared with 19,519, 1,943 and 1,970 thousand b/d in 1999. The model forecasts economic slowdown during 2000/2002. The USA and Canada are expected to recover quickly, while Mexico will take longer. (author)

Geohydrology of the Unconsolidated Valley-Fill Aquifer in the Meads Creek Valley, Schuyler and Steuben Counties, New York

Science.gov (United States)

Miller, Todd S.; Bugliosi, Edward F.; Reddy, James E.

2008-01-01

The Meads Creek valley encompasses 70 square miles of predominantly forested uplands in the upper Susquehanna River drainage basin. The valley, which was listed as a Priority Waterbody by the New York State Department of Environmental Conservation in 2004, is prone to periodic flooding, mostly in its downstream end, where development is occurring most rapidly. Hydraulic characteristics of the unconsolidated valley-fill aquifer were evaluated, and seepage rates in losing and gaining tributaries were calculated or estimated, in an effort to delineate the aquifer geometry and identify the factors that contribute to flooding. Results indicated that (1) Meads Creek gained about 61 cubic feet of flow per second (about 6.0 cubic feet per second per mile of stream channel) from ground-water discharge and inflow from tributaries in its 10.2-mile reach between the northernmost and southernmost measurement sites; (2) major tributaries in the northern part of the valley are not significant sources of recharge to the aquifer; and (3) major tributaries in the central and southern part of the valley provide recharge to the aquifer. The ground-water portion of streamflow in Meads Creek (excluding tributary inflow) was 11.3 cubic feet per second (ft3/s) in the central part of the valley and 17.2 ft3/s in the southern part - a total of 28.5 ft3/s. Ground-water levels were measured in 29 wells finished in unconfined deposits for construction of a potentiometric-surface map to depict directions of ground-water flow within the valley. In general, ground water flows from the edges of the valley toward Meads Creek and ultimately discharges to it. The horizontal hydraulic gradient for the entire 12-mile-long aquifer averages about 30 feet per mile, whereas the gradient in the southern fourth of the valley averages about half that - about 17 feet per mile. A water budget for the aquifer indicated that 28 percent of recharge was derived from precipitation that falls on the aquifer, 32

The new 99mTc myocardial perfusion imaging agents: 99mTc-sestamibi and 99mTc-teboroxime

International Nuclear Information System (INIS)

Berman, D.S.; Kiat, H.; Maddahi, J.

1991-01-01

The two new 99m (99mTc) labeled myocardial perfusion agents, 99mTc-Sestamibi and 99mTc-Teboroxime, are now available for routine clinical application. Both agents allow assessment of ejection fraction by the first-pass technique at rest or during exercise, thus providing additional information not available with thallium-201. 99mTc-Sestamibi has long myocardial residence time, as well as adequate myocardial extraction, providing images of higher count density and superior quality compared with thallium-201. 99mTc-Teboroxime has excellent myocardial uptake characteristics but is cleared very rapidly from the myocardium. Both tracers have shown results similar to those obtained with thallium-201 for detection of coronary artery disease and the assessment of defect reversibility. 99mTc-Sestamibi studies using the rest/stress imaging sequence can be accomplished in approximately 5 hours; studies using dual-isotope imaging (rest thallium-201 and stress 99mTc-Sestamibi injection) can be completed in 1 to 2 hours. Gated stress images can be performed with 99mTc-Sestamibi, providing simultaneous information of myocardial perfusion at stress and resting wall motion or thickening and allowing rapid differentiation of ischemic from infarcted tissue. Because of its slow myocardial clearance and absence of redistribution, 99mTc-Sestamibi allows uncoupling of the time of injection from the time of imaging and thus can be valuable in the evaluation of acute myocardial infarction and outcome of thrombolytic therapy. With 99mTc-Teboroxime, rapid serial studies are feasible. Pharmacologic stress and rest studies with 99mTc-Teboroxime single photon emission computed tomography potentially can be completed in under 30 minutes. 73 references

7 CFR 1980.308 - Full faith and credit.

Science.gov (United States)

2010-01-01

... 7 Agriculture 14 2010-01-01 2009-01-01 true Full faith and credit. 1980.308 Section 1980.308...) PROGRAM REGULATIONS (CONTINUED) GENERAL Rural Housing Loans § 1980.308 Full faith and credit. The loan note guarantee constitutes an obligation supported by the full faith and credit of the United States...

Monitoring the hydrologic system for potential effects of geothermal and ground-water development in the Long Valley Caldera, Mono County, California, USA

International Nuclear Information System (INIS)

Farrar, C.D.; Lyster, D.L.

1990-01-01

In the early 1980's, renewed interest in the geothermal potential of the Long valley caldera, California, highlighted the need to balance the benefits of energy development with the established recreational activities of the area. The Long Valley Hydrologic Advisory Committee, formed in 1987, instituted a monitoring program to collect data during the early stages of resource utilization to evaluate potential effects on the hydrologic system. This paper reports that early data show declines in streamflow, spring flow, and ground-water levels caused by 6 years of below-average precipitation. Springs in the Hot Creek State Fish Hatchery area discharge water that is a mixture of nonthermal and hydrothermal components. Possible sources of nonthermal water have been identified by comparing deuterium concentrations in streams and springs. The equivalent amount of undiluted thermal water discharged from the springs was calculated on the basis of boron and chloride concentrations. Quantifying the thermal and nonthermal fractions of the total flow may allow researchers to assess changes in flow volume or temperature of the springs caused by ground-water or geothermal development

99Mo-99mTc production development by (n, γ) reaction

International Nuclear Information System (INIS)

Izumo, Hironobu; Nishikata, Kaori; Kimura, Akihiro; Tanimoto, Masataka; Tsuchiya, Kunihiko; Ishihara, Masahiro; Kaminaga, Masanori

2012-01-01

The renewed JMTR will be started from the later half of JFY2012, and it is expected to various fields. Supply of 99 Mo in Japan depends only on imports from foreign countries. JAEA has a plan to produce 99 Mo, a parent nuclide of 99m Tc. JMTR will contribute to produce 99 Mo by (n, r) method as one of effective uses of the JMTR. In this paper, outline of the technical study items for production method of 99 Mo- 99m Tc in JMTR will be described. (author)

A modified {sup 99} Mo- {sup 99} Tc generator on Zirconium molybdo- phosphate-{sup 99} Mo gel. Vol. 3

Energy Technology Data Exchange (ETDEWEB)

El-Kolaly, M T; Talaat, H [Labelled Compounds Department, Cairo (Egypt); Botros, N [Radioistspe and Generator Department, Radioisotope Production and Sealed Source Division, Hot Laboratories Center, Atomic Energy Authority, Cairo (Egypt)

1996-03-01

A modified {sup 99} Mo - {sup 99} Tc gel generator is described. The new generator is based on the use of zirconium molybdophosphate - {sup 99} Mo gel in which {sup 99} Mo chemically combined in the gel structure, where {sup 99m}Tc can be easily eluted with distilled water or saline. The gel was prepared via chemical reaction between zirconyl chloride and molybdophosphate - {sup 99} Mo solution. The PH of the reaction mixture was adjusted with NaOH. Different gels have been prepared by varying the molar ratio of Mo:Zr:p. The PH and time of digeston on complete gel formation was also investigated in order to optimize the condition of gel preparation. Molybdophosphate {sup 32} P solution was used to determine the phosphorous content in the gel and in the {sup 99m}Tc eluate. The temperature and time of drying of the gel and their effect on {sup 99m}Tc elution efficiency were also studied. From the data obtained, the optimum conditions for routine production of {sup 99} Mo - {sup 99m}Tc generator are presented and discussed. 2 figs., 6 tabs.

Non-destructive examination of a time capsule recovered from the Gore Park excavations, Hamilton, Ontario

International Nuclear Information System (INIS)

MacDonald, B.L.; Vanderstelt, J.

2015-01-01

Non-destructive analytical techniques are becoming increasingly important for the study of objects of cultural heritage interest. We present a study that applied two techniques: x-ray fluorescence (XRF) and neutron radiography, for the investigation of a time capsule recovered from an urban construction site in Gore Park, Hamilton. XRF analysis revealed the composition of the artifact, while n-radiography showed that its contents remained intact after being interred for 91 years. Results of this study demonstrate the value of non-destructive techniques for the analysis and preservation of cultural heritage. (author)

Strontium-90 and cesium-137 in total diet; from June 1980 to Dec. 1980

International Nuclear Information System (INIS)

1980-01-01

A full one day ordinary diet including three meals, water, tea and other in-between snacks for five persons was collected as a sample of ''total diet''. The sample in a large stainless steel pan was carbonized carefully by direct application of gas flame, and was transferred to a porcelain dish and then ashed at 500 0 C in an electric muffle furnace. The results obtained from June 1980 to December 1980 were shown in a table. (J.P.N.)

Valley and spin thermoelectric transport in ferromagnetic silicene junctions

International Nuclear Information System (INIS)

Ping Niu, Zhi; Dong, Shihao

2014-01-01

We have investigated the valley and spin resolved thermoelectric transport in a normal/ferromagnetic/normal silicene junction. Due to the coupling between the valley and spin degrees of freedom, thermally induced pure valley and spin currents can be demonstrated. The magnitude and sign of these currents can be manipulated by adjusting the ferromagnetic exchange field and local external electric field, thus the currents are controllable. We also find fully valley and/or spin polarized currents. Similar to the currents, owing to the band structure symmetry, tunable pure spin and/or valley thermopowers with zero charge counterpart are generated. The results obtained here suggest a feasible way of generating a pure valley (spin) current and thermopower in silicene

Concentration of sup(99m)Tc from the eluate of 99Mo-sup(99m)Tc generators

International Nuclear Information System (INIS)

Saucedo, T.; Mora, M.; Fraga de Suarez, A.H.; Mitta, A.E.A.

1976-04-01

A method is described to concentrate sup(99m)Tc solutions, originated in 99 Mo-sup(99m)Tc generators, independent of its age. The techniques of preparation of the different radiopharmaceuticals used in nuclear medicine are also described. (author) [es

Problems in clinical practice of domestic supply of 99Mo/99mTc. Considerations on the domestic production of 99Mo/99mTc

International Nuclear Information System (INIS)

Yamabayashi, Hisamichi

2012-01-01

At present, a bulky import product, 99 Mo supplied in Japan is produced by a nuclear fission method which enables to produce a generator system with no need of commercially preparing 99m Tc-labeled radiopharmaceuticals due to its high specific activity. However its usage of enriched uranium target leads to avoiding the fission method from the option of domestic production. In order to secure the domestic supply of 99 Mo/ 99m Tc, the neutron activation method, aiming to meet about 20% of domestic demand, is under development along with the re-start program of JMTR. Development of various production methods using accelerators are also in progress. In those non-fission methods with reactors or accelerators, rapid and effective procedures for concentration and refinement of 99m Tc solution eluted from 99 Mo of low specific activity are the subjects to be considered for attaining the stable labeling performances. (author)

Daresbury 1980

International Nuclear Information System (INIS)

1981-01-01

This annual report of the Daresbury Laboratory describes work carried out during 1980 on: (1) Synchrotron radiation (synchrotron radiation source, synchrotron radiation experiments, theoretical studies, new projects). (2) Nuclear structure (nuclear structure facility, experimental physics, nuclear physics). (3) Computer services and computational science. (4) Laboratory services. Publications are listed in an appendix. (U.K.)

Field differential equations for a potential flow from a Hamilton type variational principle

International Nuclear Information System (INIS)

Fierros Palacios, A.

1992-01-01

The same theoretical frame that was used to solve the problem of the field equations for a viscous fluid is utilized in this work. The purpose is to obtain the differential field equations for a potential flow from the Lagrangian formalism as in classical field theory. An action functional is introduced as a space-time integral over a region of three-dimensional Euclidean space, of a Lagrangian density as a function of certain field variables. A Hamilton type extremum action principle is postulated with adequate boundary conditions, and a set of differential field equations is derived. A particular Lagrangian density of the T-V type leads to the wave equation for the velocity potential. (Author)

Engineering assessment of inactive uranium mill tailings: Monument Valley Site, Monument Valley, Arizona

Energy Technology Data Exchange (ETDEWEB)

1981-10-01

Ford, Bacon and Davis Utah Inc. has reevalated the Monument Valley site in order to revise the March 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Monument Valley, Arizona. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposure of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 1.1 million tons of tailings at the Monument Valley site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors. The four alternative actions presented in this engineering assessment range from millsite decontamination with the addition of 3 m of stabilization cover material (Option I), to removal of the tailings to remote disposal sites and decontamination of the tailings site (Options II through IV). Cost estimates for the four options range from about $6,600,000 for stabilization in-place, to about $15,900,000 for disposal at a distance of about 15 mi. Three principal alternatives for reprocessing the Monument Valley tailings were examined: heap leaching; Treatment at an existing mill; and reprocessing at a new conventional mill constructed for tailings reprocessing. The cost of the uranium recovery is economically unattractive.

Engineering assessment of inactive uranium mill tailings: Monument Valley Site, Monument Valley, Arizona

International Nuclear Information System (INIS)

1981-10-01

Ford, Bacon and Davis Utah Inc. has reevalated the Monument Valley site in order to revise the March 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Monument Valley, Arizona. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposure of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 1.1 million tons of tailings at the Monument Valley site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors. The four alternative actions presented in this engineering assessment range from millsite decontamination with the addition of 3 m of stabilization cover material (Option I), to removal of the tailings to remote disposal sites and decontamination of the tailings site (Options II through IV). Cost estimates for the four options range from about $6,600,000 for stabilization in-place, to about $15,900,000 for disposal at a distance of about 15 mi. Three principal alternatives for reprocessing the Monument Valley tailings were examined: heap leaching; Treatment at an existing mill; and reprocessing at a new conventional mill constructed for tailings reprocessing. The cost of the uranium recovery is economically unattractive

Sustainable agricultural development in inland valleys

NARCIS (Netherlands)

Zwart, S.J.

2018-01-01

The inland valley in Africa are common landscapes that have favorable conditions for agricultural production. Compared to the surrounding uplands they are characterized by a relatively high and secure water availability and high soil fertility levels. Inland valleys thus have a high agricultural

Valley-polarized quantum transport generated by gauge fields in graphene

Science.gov (United States)

Settnes, Mikkel; Garcia, Jose H.; Roche, Stephan

2017-09-01

We report on the possibility to simultaneously generate in graphene a bulk valley-polarized dissipative transport and a quantum valley Hall effect by combining strain-induced gauge fields and real magnetic fields. Such unique phenomenon results from a ‘resonance/anti-resonance’ effect driven by the superposition/cancellation of superimposed gauge fields which differently affect time reversal symmetry. The onset of a valley-polarized Hall current concomitant to a dissipative valley-polarized current flow in the opposite valley is revealed by a {{e}2}/h Hall conductivity plateau. We employ efficient linear scaling Kubo transport methods combined with a valley projection scheme to access valley-dependent conductivities and show that the results are robust against disorder.

Labelled Preformed liposomes with 99MTC-DTPA, 99 MTC-ECD, 99MTC-MDP and 99MTC-MIBI : Labelling procedures and stability studies

International Nuclear Information System (INIS)

Savio, E.O.; Teran, M.A.; Vales, M.E.; Frier, M.

2004-01-01

Liposomes labelled with gamma e miters like 99mTc, can be used for scintigraphic imaging to non-invasively track and quantify the distribution of liposomes in the body. In vitro studies were done to choose a suitable radiopharmaceutical (RF) to be attached to performed liposomes. 99mTc-Complexes (DTPA, ECD, MDP, MIBI) were used to label collagen liposomes. Commercial kits were labelled with 99mTc04-(TechnoNuclear). Quality controls of the RF were performed. Collagen liposomes suspended in saline 0.9% were incubated at 4.25.37 and 60 for 30 min. Efficiency of the labelling procedure was determined by gel filtration using Sephadex G25 (Pharmacia) and NaC10.9%. Samples of 100mL (74MBq), were seeded and fractions of 0.5mL were colleted and measured in an ionisation chamber (Capintec CRC). Stability of the labelled liposomes was assessed incubating 0.5mL, of the suspension with 1mL of human serum during 30 min at 37 . Dialysis was performed using dialysis bags of 64 K pore size and NaCI 0.9% at room temperature. Samples of the saline bath were collected at 30.60 and 90 min. and measured in a solid scintillation counter Ortec.Liposomes labelled with 99mTc-DTPA and 99mTcMIBI showed a labelling efficiency of 80%; liposomes incubated with 99mTc-MDP were labelled in a 50% and 99mTc-ECD did not bind to liposomes in the conditions of study. Incubation of labelled liposomes with human serum showed 50% of strong binding to the plasmatic proteins for 99mTc-DTPA but low values (5%) for the other specimens. Labelled liposomes were achieved, with different RF, showing a suitable in vitro stability to perform in vivo studies

Balance equations for a viscous fluid from a Hamilton type variational principle

International Nuclear Information System (INIS)

Fierros Palacios, A.

1992-01-01

The partial differential field equations for any viscous fluid are obtained from the Lagrangian formalism as in classical field theory. An action functional is introduced as a space-time integral over a region of three-dimensional Euclidean space, of a Lagrangian density function of certain field variables. A Hamilton type extremum action principle is postulated with adequate boundary conditions, and a set of differential field equations is derived. With an appropriate Lagrangian density of the T-V type, the equation of motion for any viscous fluid is reproduced. A theorem referring to the invariance of the action under time variations lead to the generalized energy balance equation for the viscous fluid and to the energy balance equation proper. The same theoretical approach can be used to solve the problem of potential flow. (Author)

Comparative study of 99Mo/99mTc generators at base of synthesized gels starting from activation and fission 99Mo

International Nuclear Information System (INIS)

Lopez M, I.Z.; Monroy G, F.; Rivero G, T.; Rojas N, P.

2007-01-01

The 99m Tc is used for diagnostic and therapy. It is produced starting from 99 Mo, absorbed in chromatographic columns, loaded with alumina that absorb only 0.2% of 99 Mo with high specific activities of 99 Mo, obtained from the 235 U fission. Given these conditions and limitations, new preparation procedures of 99 Mo/ 99m Tc generators, its have been developed, using zirconium molybdates gels that incorporates until 30% of 99 Mo, conserve similar characteristics of quality and purity that the traditional generator. The radiochemical characteristics of the 99m Tc elution, depend strongly on the gel preparation conditions. In particular, the present work has by object to determine the influence of the 99 Mo used type, fission or activation product, during the gels synthesis, as well as the used air flow for the agitation in the gels preparation and its influence in the 99 Mo/ 99m Tc generators quality. When diminishing the flow of agitation air the efficiency it increases and in the radionuclide purity of the eluates and when using 99 Mo from fission for the gels production it increases in an important way the elutriation efficiency, the radiochemical and radionuclide purity of the 99m Tc eluates. (Author)

Environment, 1980-1993

International Nuclear Information System (INIS)

1994-01-01

This document lists all sales publications of the International Atomic Energy Agency dealing with Environment issued during the period 1980-1993. It gives a short abstract and contents of these issues along with their costs in Austrian Schillings

Three-Dimensional P-wave Velocity Structure Beneath Long Valley Caldera, California, Using Local-Regional Double-Difference Tomography

Science.gov (United States)

Menendez, H. M.; Thurber, C. H.

2011-12-01

Eastern California's Long Valley Caldera (LVC) and the Mono-Inyo Crater volcanic systems have been active for the past ~3.6 million years. Long Valley is known to produce very large silicic eruptions, the last of which resulted in the formation of a 17 km by 32 km wide, east-west trending caldera. Relatively recent unrest began between 1978-1980 with five ML ≥ 5.7 non-double-couple (NDC) earthquakes and associated aftershock swarms. Similar shallow seismic swarms have continued south of the resurgent dome and beneath Mammoth Mountain, surrounding sites of increased CO2 gas emissions. Nearly two decades of increased volcanic activity led to the 1997 installation of a temporary three-component array of 69 seismometers. This network, deployed by the Durham University, the USGS, and Duke University, recorded over 4,000 high-frequency events from May to September. A local tomographic inversion of 283 events surrounding Mammoth Mountain yielded a velocity structure with low Vp and Vp/Vs anomalies at 2-3 km bsl beneath the resurgent dome and Casa Diablo hot springs. These anomalies were interpreted to be CO2 reservoirs (Foulger et al., 2003). Several teleseismic and regional tomography studies have also imaged low Vp anomalies beneath the caldera at ~5-15 km depth, interpreted to be the underlying magma reservoir (Dawson et al., 1990; Weiland et al., 1995; Thurber et al., 2009). This study aims to improve the resolution of the LVC regional velocity model by performing tomographic inversions using the local events from 1997 in conjunction with regional events recorded by the Northern California Seismic Network (NCSN) between 1980 and 2010 and available refraction data. Initial tomographic inversions reveal a low velocity zone at ~2 to 6 km depth beneath the caldera. This structure may simply represent the caldera fill. Further iterations and the incorporation of teleseismic data may better resolve the overall shape and size of the underlying magma reservoir.

An example of Alaknanda valley, Garhwal Himalaya, India

Indian Academy of Sciences (India)

2014) have been best explained by the geometry .... flows through narrow valley confined by the steep valley slopes. ... valley (figure 3b) which opens up around Srina- ... Method. 4.1 Drainage basin and stream network. Digital Elevation Model (DEM) helps in extracting ... was processed to fill the pits or sinks, and to obtain.

Gentc99m, computational system for the technetium-99m generator

International Nuclear Information System (INIS)

Suparman, I.

1997-01-01

The technetium-99m generator is one of the main products of the PPR, as the continuity of the technetium-99m generator production is important for supporting the development of nuclear medicine. GENTC99M has been made for computational for the technetium-99m generator and includes data processing, documentation and information GENTC99M is also very useful in quality control application especially for the determinations of yield and radionuclidic impurities which consume much time. microsoft visual basic for MS-DOS and visual basic for windows have been used for making GENTC99M. Microsoft visual basic has several features that make it an ideal development language for both MS-DOS and Microsoft Windows. These features not only increase productivity, they also provide all the tools and hooks needed to develop some very sophisticated applications. for a production centre like PPR, GENTC99M is very useful to support the data processing, documentation and information system of the technetium-99m generator and it can also be modified for other products

Characterizing the Stellar Population of NGC 1980

Energy Technology Data Exchange (ETDEWEB)

Kounkel, Marina; Hartmann, Lee; Calvet, Nuria [Department of Astronomy, University of Michigan, 1085 S. University Street, Ann Arbor, MI 48109 (United States); Megeath, Tom, E-mail: mkounkel@umich.edu [Ritter Astrophsical Research Center, Department of Physics and Astronomy, University of Toledo, Toledo, OH 43606 (United States)

2017-07-01

NGC 1980 is a young cluster that is located about 0.°5 south of the Orion Nebula Cluster (ONC). Recent studies by Bouy et al. and Pillitteri et al. have suggested that NGC 1980 contains an older population of stars compared to a much younger ONC, and that it belongs to a foreground population that may be located in front of the Orion A molecular gas by as much as 40 pc. In this work, we present low-resolution spectra toward 148 young stars found toward the NGC 1980 region. We determine the spectral types of these stars, examine accretion signatures and measure the extinction toward them. We determine that based on these observations, the age of the population of NGC 1980 is indistinguishable from L1641, estimated to be ∼3 Myr, comparable with the study by Fang et al.

Results of the radiological survey at Diebold Safe Company, 1550 Grand Boulevard, Hamilton, Ohio (HO001)

International Nuclear Information System (INIS)

Foley, R.D.; Floyd, L.M.

1990-02-01

At the request of the US Department of Energy (DOE), a group from Oak Ridge National Laboratory conducted investigative radiological surveys at Diebold Safe Company, 1550 Grand Boulevard, Hamilton, Ohio in 1988 and 1989. The purpose of the surveys was to determine whether the property was contaminated with radioactive residues, principally 238 U. The surveys included gamma scans; direct and transferable measurements of alpha, beta, and gamma radiation levels; and dust, debris, air, and soil sampling for radionuclide analyses. 6 refs., 6 figs., 5 tabs

Mismatched uptake of Tc-99m-ECD and Tc-99m-HMPAO in subacute cerebral infarction: Tc-99m-ECD for viability and Tc-99m-HMPAO for flow restoration

Energy Technology Data Exchange (ETDEWEB)

Lee, D. S.; Hyun, I. Y.; Kim, S. K. [College of Medicine, Seoul National Univ., Seoul (Korea, Republic of)] [and others

1997-07-01

Tc-99m-HMPAO reflects tissue perfusion but Tc-99m-ECD uptake is affected by tissue viability in addition to tissue perfusion which the varied state of cellular retention of Tc-99m-ECD reflects. Luxuriously perfused area on Tc-99m-HMPAO SPECT implies that this cortex was already reperfused either spontaneously or after thrombolysis and that accompanied paralysis of vascular reactivity in those zones warms progressive deterioration. We tried to find out if we can use sequential Tc-99m-ECD/Tc-99m-HMPAO SPECT to reveal cortical perfusion and severity and range of risky areas of cerbral cortex despite reperfusion in sub-acute infarction. In 13 patients (M ; F =7 : 6, mean age 57 (range: 26-84)) with cortical (n=12) and basal ganglia infarction (1), we performed sequential Tc-99m-ECD/Tc-99m-HMPAO SPECT at the same position. At first, 555 MBq of Tc-99m-ECD was injected and imaged and then 1110 MBq of Tc-99m-HMPAO was injected again and imaged with the patients in situ, and the first image (Tc-99m-ECD) and the subtracted image (2nd- 1st : Tc-99m-HMPAO) were compared slice by slice. Study was done from 3 days to 31 days (16{+-}9) after ictus. Tc-99m-ECD uptake was always less than or equal to Tc-99m-HMPAO uptake at the lesion in all cases. Luxury perfusion was prominent in four patients. Mismatched uptake was found in 10 patients. Severity of mismatch showed diverse spectrum and was ranged from total middle cerebral artery territory (1 case) to peripheral thin zones around infarction (2 cases). The other 7 showed intermediate amount of tissues with mismatch , i.e., Tc-99m-ECD defects where Tc-99m-HMPAO uptake is in part increased, normal or decreased. Upon discharge, patients having more uptake with Tc-99m-ECD predicted improvement. Patients having mismatched uptake went dichotomous way. In conclusion, Tc-99m-ECD/Tc-99m-HMPAO sequential SPECT is feasible and reveal both tissue perfusion (Tc-99m-HMPAO ) and discrepant Tc-99m-ECD uptake probably reflecting viability in acute

Vivid valleys, pallid peaks? Hypsometric variations and rural-urban land change in the Central Peruvian Andes.

Science.gov (United States)

Haller, Andreas

2012-11-01

What happens to the land cover within the hinterland's altitudinal belts while Central Andean cities are undergoing globalization and urban restructuring? What conclusions can be drawn about changes in human land use? By incorporating a regional altitudinal zonation model, direct field observations and GIS analyses of remotely sensed long term data, the present study examines these questions using the example of Huancayo Metropolitano - an emerging Peruvian mountain city of 420,000 inhabitants, situated at 3260 m asl in the Mantaro Valley. The study's results indicate that rapid urban growth during the late 1980s and early 1990s was followed by the agricultural intensification and peri-urban condominization at the valley floor ( quechua ) - since the beginning of Peru's neoliberal era. Moreover, regarding the adjoining steep slopes ( suni ) and subsequent grassland ecosystems ( puna ), the research output presents land cover change trajectories that clearly show an expansion of human land use, such as reforestation for wood production and range burning for livestock grazing, even at high altitudes - despite rural-urban migration trends and contrary to several results of extra-Andean studies. Consequently, rural-urban planners and policy makers are challenged to focus on the manifold impacts of globalization on human land use - at all altitudinal belts of the Andean city's hinterland: toward sustainable mountain development that bridges the social and physical gaps - from the bottom up.

Valley Fever

Science.gov (United States)

... valley fever. These fungi are commonly found in soil in specific regions. The fungi's spores can be stirred into the air by ... species have a complex life cycle. In the soil, they grow as a mold with long filaments that break off into airborne ...

Nematic and Valley Ordering in Anisotropic Quantum Hall Systems

Science.gov (United States)

Parameswaran, S. A.; Abanin, D. A.; Kivelson, S. A.; Sondhi, S. L.

2010-03-01

We consider a multi-valley two dimensional electron system in the quantum Hall effect (QHE) regime. We focus on QHE states that arise due to spontaneous breaking of the valley symmetry by the Coulomb interactions. We show that the anisotropy of the Fermi surface in each valley, which is generally present in such systems, favors states where all the electrons reside in one of the valleys. In a clean system, the valley ordering occurs via a finite temperature Ising-like phase transition, which, owing to the Fermi surface anisotropy, is accompanied by the onset of nematic order. In a disordered system, domains of opposite polarization are formed, and therefore long-range valley order is destroyed, however, the resulting state is still compressible. We discuss the transport properties in ordered and disordered regimes, and point out the possible relation of our results to recent experiments in AlAs [1]. [1] Y. P. Shkolnikov, S. Misra, N. C. Bishop, E. P. De Poortere, and M. Shayegan, Observation of Quantum Hall ``Valley Skyrmions", Phys. Rev. Lett. 95, 068809 (2005)[2] D.A. Abanin, S.A. Parameswaran, S.A. Kivelson and S.L. Sondhi, Nematic and Valley Ordering in Anisotropic Quantum Hall Systems, to be published.

Preparation of 99Mo/99mTc generators based on 99Mo zirconium molybdates in the Gel Synthesis Device for Generators

International Nuclear Information System (INIS)

Lopez M, I. Z.; Monroy G, F.; Rivero G, T.; Rojas N, P.

2008-01-01

The 99m Tc is used for diagnosis and therapy. It is produced commercially from 99 Mo obtained from the fission of 235 U, which is retained in chromatographic columns filled with alumina whose maximum capacity is 0.2%. Given these constraints new methods of preparation 99 Mo/ 99m Tc generators have been developed using zirconium molybdates gels containing up to 30% of Mo, which is part of the generator matrix, and retaining quality and purity similar characteristics to those commercial generators. The present study aims to determine the flow of agitation, temperature and drying time optimal to prepare 99 Mo/ 99m Tc generators based on 99 Mo zirconium molybdates in the Gel Synthesis Device 99 Mo/ 99m Tc Generators designed and built by groups of the Radioactive Materials Research Laboratory and Automation and Instrumentation Department of the National Institute of Nuclear Research. (Author)

Annual Report 1980

International Nuclear Information System (INIS)

1981-01-01

This Annual Report covers the activities of the Institute of the Nuclear Physics Accelerator (KVI) during the year 1980. The main lines of research are on experimental nuclear physics and on nuclear theory. The experimental work of the laboratory is centred around a large and modern, k=160 MeV AVF cyclotron that became operational at the end of 1972. The experimental work in 1980 concentrated on high-resolution nuclear structure studies via transfer reactions and inelastic scattering, on the decay properties of giant resonances, on elastic and inelastic breakup of light and heavy ions, on the investigation of continuum γ-rays, on in-beam γ-ray and conversion electron spectroscopy, and on weak interactions. Much of the theoretical work was directed towards the Interacting Boson Model (IBM). Another major effort was done on the theoretical description of relativistic heavy-ion reactions via a Boltzmann equation approach. (Auth.)

Altered [99mTc]Tc-MDP biodistribution from neutron activation sourced 99Mo.

Science.gov (United States)

Demeter, Sandor; Szweda, Roman; Patterson, Judy; Grigoryan, Marine

2018-01-01

Given potential worldwide shortages of fission sourced 99 Mo/ 99m Tc medical isotopes there is increasing interest in alternate production strategies. A neutron activated 99 Mo source was utilized in a single center phase III open label study comparing 99m Tc, as 99m Tc Methylene Diphosphonate ([ 99m Tc]Tc-MDP), obtained from solvent generator separation of neutron activation produced 99 Mo, versus nuclear reactor produced 99 Mo (e.g., fission sourced) in oncology patients for which an [ 99m Tc]Tc-MDP bone scan would normally have been indicated. Despite the investigational [ 99m Tc]Tc-MDP passing all standard, and above standard of care, quality assurance tests, which would normally be sufficient to allow human administration, there was altered biodistribution which could lead to erroneous clinical interpretation. The cause of the altered biodistribution remains unknown and requires further research.

Monitoring the Thermal Regime at Hot Creek and Vicinity, Long Valley Caldera, Eastern California

Science.gov (United States)

Clor, L. E.; Hurwitz, S.; Howle, J.

2015-12-01

Hot Creek Gorge contains the most obvious surface expression of the hydrothermal system in Long Valley Caldera, California, discharging 200-300 L/s of thermal water according to USGS measurements made since 1988. Formerly, Hot Creek was a popular public swimming area, but it was closed in 2006 due to unpredictable temperature fluctuations and sporadic geysering of thermal water within the creek (Farrar et al. USGS Fact Sheet2007-3045). The USGS has monitored the thermal regime in the area since the mid-1980s, including a long-term series of studies 0.6 km away at well CH-10b. Temperature measurements in the ~100 m deep well, which have been performed on an intermittent basis since it was drilled in 1983, reveal a complex temperature profile. Temperatures increase with depth to a maximum at about 45 meters below the ground surface, and then decrease steadily to the bottom of the well. The depth of the temperature maximum in the well (~45 m) corresponds to an elevation of ~2,120 m, roughly equivalent to the elevation of Hot Creek, and appears to sample the same hydrothermal flow system that supplies thermal features at the surface in the gorge. Starting in the early 1990s, the maximum temperature in CH-10b rose from 93.4°C to its peak in 2007 at 101.0°C. A cooling trend was observed beginning in 2009 and continues to present (99.3°C in June 2015). As the input into CH-10b is at the elevation of the creek, it exhibits the potential for response to thermal events at Hot Creek, and could provide a useful tool for monitoring future hazards. On short timescales, CH-10b also responds to large global earthquakes, greater than ~M7. These responses are captured with continuously logged high-frequency data (5s), and are usually characterized by a co-seismic water level drop of up to ten centimeters. Water levels tend to recover to pre-earthquake levels within a few hours to days.

Inventory of karst subsidence in the Valley and Ridge Province of East Tennessee

International Nuclear Information System (INIS)

Ketelle, R.H.; Newton, J.G.

1986-01-01

The first regional inventory of karst activity in the Valley and Ridge Province of East Tennessee was performed as a part of ongoing studies at Oak Ridge National Laboratory pertaining to environmental impact assessment of waste disposal in karst settings. More than half the land area in the Valley and Ridge Province of East Tennessee is underlain by karst-prone carbonate bedrock. The regional karst inventory was initiated to obtain current information on the extent of active karst subsidence in the region for use in decision making by the Department of Energy in planning future waste disposal facilities at Oak Ridge, Tennessee. The inventory was performed by contacting personnel of federal, state, and county agencies to obtain reports of known active karst subsidence within the region. Data from these interviews were tabulated resulting in identificaton of more than 250 karst subsidence incidents in East Tennessee, most of which have occurred since 1980. Although the infomation obtained was largely anecdotal, approximate location, date, size, and circumstances under which the collapses occurred were recorded for as many cases as could be documented. The study also included detailed reconnaissance of selected areas similar in geology and hydrology to a study area at Oak Ridge, Tennessee to identify causative factors which contribute to karst subsidence in the region and for comparison of the occurrence of visible karst features at different sites. Human activities affecting site hydrology such as large scale land clearing and earthmoving projects were related to most of the subsidence incidents inventoried

Quantized Hamilton dynamics describes quantum discrete breathers in a simple way

International Nuclear Information System (INIS)

Igumenshchev, Kirill; Prezhdo, Oleg

2011-01-01

We study the localization of energy in a nonlinear coupled system, exhibiting so-called breather modes, using quantized Hamilton dynamics (QHD). Already at the lowest order, which is only twice as complex as classical mechanics, this simple semiclassical method incorporates quantum-mechanical effects. The transition between the localized and delocalized regimes is instantaneous in classical mechanics, while it is gradual due to tunneling in both quantum mechanics and QHD. In contrast to classical mechanics, which predicts an abrupt appearance of breathers, quantum mechanics and QHD show an alternation of localized and delocalized behavior in the transient region. QHD includes zero-point energy that is reflected in a shifted energy asymptote for the localized states, providing another improvement on the classical perspective. By detailed analysis of the distribution and transfer of energy within classical mechanics, QHD, and quantum dynamics, we conclude that QHD is an efficient approach that accounts for moderate quantum effects and can be used to identify quantum breathers in large nonlinear systems.

Preparation and biological profile of 99mTc-lidocaine as a cardioselective imaging agent using 99mTc eluted from 99Mo/99mTc generator based on Al-Mo gel

International Nuclear Information System (INIS)

Sakr, T.M.; October University of Modern Sciences and Arts; Ibrahim, A.B.; Rashed, H.M.; Fasih, T.W.

2017-01-01

The current study is aimed to prepare 99m Tc-lidocaine as a new myocardial perfusion-imaging agent. The used 99m Tc was obtained from Al- 99 Mo-molybdate(VI) gel matrix. 99m Tc-lidocaine showed higher (15.4 ± 0.11% ID/g) and faster (15 min post injection) cardiac uptake than the recently studied 99m Tc-valsartan and 99m Tc-procainamide. Consequently, 99m Tc-lidocaine will be a valuable myocardial SPECT agent for diagnosis of emergency patients. Besides, the receptor affinity study confirmed the selectivity of 99m Tc-lidocaine for sodium channels in the heart. (author)

Nuclear Safety Project - annual report 1980

International Nuclear Information System (INIS)

1981-08-01

The Annual Report 1980 is a detailed description (in German language) of work within the Nuclear Safety Project performed in 1980 in the nuclear safety field by KfK institutes and departments and by external institutes on behalf of KfK. It includes for each individual research activity short summaries in English language on work completed, essential results, plans for the near future. (orig./RW) [de

Valley photonic crystals for control of spin and topology.

Science.gov (United States)

Dong, Jian-Wen; Chen, Xiao-Dong; Zhu, Hanyu; Wang, Yuan; Zhang, Xiang

2017-03-01

Photonic crystals offer unprecedented opportunity for light manipulation and applications in optical communication and sensing. Exploration of topology in photonic crystals and metamaterials with non-zero gauge field has inspired a number of intriguing optical phenomena such as one-way transport and Weyl points. Recently, a new degree of freedom, valley, has been demonstrated in two-dimensional materials. Here, we propose a concept of valley photonic crystals with electromagnetic duality symmetry but broken inversion symmetry. We observe photonic valley Hall effect originating from valley-dependent spin-split bulk bands, even in topologically trivial photonic crystals. Valley-spin locking behaviour results in selective net spin flow inside bulk valley photonic crystals. We also show the independent control of valley and topology in a single system that has been long pursued in electronic systems, resulting in topologically-protected flat edge states. Valley photonic crystals not only offer a route towards the observation of non-trivial states, but also open the way for device applications in integrated photonics and information processing using spin-dependent transportation.

Comparative study of 99Mo/99mTc generators at base of synthesized gels starting from 99Mo of activation and of fission

International Nuclear Information System (INIS)

Lopez M, I.Z.; Monroy G, F.; Rivero G, T.; Rojas N, P.

2007-01-01

At the present time the more used and diffused radionuclide in nuclear medicine it is the Technetium 99 metastable ( 99 mTc) it is used for diagnostic and therapy. It is produced starting from molybdenum 99 ( 99 Mo), which is absorbed in chromatographic columns, loaded with alumina that absorb only 0.2% of 99 Mo situation that forces to use high specific activities of 99 Mo that it is obtained starting from the fission of the 235 U. Given these conditions and limitations, new preparation procedures of 99 Mo/ 99m Tc generators, of low or medium specific activity, its have been developed, using gels of zirconium molybdates that incorporates until 30% in weight of 99 Mo in the gel, and also conserve similar characteristics of quality and purity that those obtained by the traditional generator; reducing by this way the cost of production of the 99m Tc, when using 99 Mo of low specific activity, in the preparation of 99 Mo/ 99m Tc generators. The radiochemical characteristics of the elution of 99m Tc, depends strongly on the gel preparation conditions. In particular, the present work has for object to determine the influence of the used type of 99 Mo, fission or activation product, during the gels synthesis, as well as the used air flow for the agitation in the gels preparation and its influence in the quality of the 99 Mo/ 99m Tc generators. When diminishing the agitation air flow the efficiency it increases and in the radionuclide purity of the eluates and when using 99 Mo of fission for the gels production it increases in an important way the elution efficiency, the radiochemical purity and radionuclide of the eluates of 99m Tc. (Author)

Technetium-99 in ''instant'' sup(99m)Tc-pertechnetate

International Nuclear Information System (INIS)

Mattsson, S.

1978-01-01

The 99 Tc-content in sup(99m)Tc-pertechnetate separated from 99 Mo by distillation or extraction has been studied with a plastic scintillation detector. The identification of the measured activity was achieved by beta-spectrometry, chemical separation and half-life studies. The frequency distribution of the sup(99)Tc/sup(99m)Tc-ratios in the different samples was observed to be log-normal. The most likely activity ratio was 0.4x10 -6 , the maximum value being 5x10 -6 . The specific activity of ''instant'' pertechnetate is approximately a factor of 60 lower than that normally recorded in pertechnetate derived from daily eluted column generators. The low specific activity of ''instant'' pertechnetate is primarily explained by the long time between separation and usage and secondly by the low yield of Tc in the distillation and extraction processes. In several of the ''instant'' pertechnetate solutions the carrier concentration exceeded the reductive capacity of the stannous ions in ''kits'' with small amounts of Sn(II) in usable form. (T.G.)

Valley Hall effect and Nernst effect in strain engineered graphene

Science.gov (United States)

Niu, Zhi Ping; Yao, Jian-ming

2018-04-01

We theoretically predict the existence of tunneling valley Hall effect and Nernst effect in the normal/strain/normal graphene junctions, where a strained graphene is sandwiched by two normal graphene electrodes. By applying an electric bias a pure transverse valley Hall current with longitudinal charge current is generated. If the system is driven by a temperature bias, a valley Nernst effect is observed, where a pure transverse valley current without charge current propagates. Furthermore, the transverse valley current can be modulated by the Fermi energy and crystallographic orientation. When the magnetic field is further considered, we obtain a fully valley-polarized current. It is expected these features may be helpful in the design of the controllable valleytronic devices.

Potential Ways to Address Shortage Situations of 99Mo/99mTc.

Science.gov (United States)

Filzen, Leah M; Ellingson, Lacey R; Paulsen, Andrew M; Hung, Joseph C

2017-03-01

99m Tc, the most common radioisotope used in nuclear medicine, is produced in a nuclear reactor from the decay of 99 Mo. There are only a few aging nuclear reactors around the world that produce 99 Mo, and one of the major contributors, the National Research Universal (Canada), ceased production on October 31, 2016. The National Research Universal produced approximately 40% of the world's 99 Mo supply, so with its shut down, shortages of 99 Mo/ 99m Tc are expected. Methods: Nuclear pharmacies and nuclear medicine departments throughout the United States were contacted and asked to provide their strategies for coping with a shortage of 99 Mo/ 99m Tc. Each of these strategies was evaluated on the basis of its effectiveness for conserving 99m Tc while still meeting the needs of the patients. Results: From the responses, the following 6 categories of strategies, in order of importance, were compiled: contractual agreements with commercial nuclear pharmacies, alternative imaging protocols, changes in imaging schedules, software use, generator management, and reduction of ordered doses or elimination of backup doses. Conclusion: The supply chain of 99 Mo/ 99m Tc is quite fragile; therefore, being aware of the most appropriate coping strategies is crucial. It is essential to build a strong collaboration between the nuclear pharmacy and nuclear medicine department during a shortage situation. With both nuclear medicine departments and nuclear pharmacies implementing viable strategies, such as the ones proposed, the amount of 99m Tc available during a shortage situation can be maximized. © 2017 by the Society of Nuclear Medicine and Molecular Imaging.

Disorder-dependent valley properties in monolayer WSe2

KAUST Repository

Tran, Kha

2017-07-19

We investigate the effect of disorder on exciton valley polarization and valley coherence in monolayer WSe2. By analyzing the polarization properties of photoluminescence, the valley coherence (VC) and valley polarization (VP) are quantified across the inhomogeneously broadened exciton resonance. We find that disorder plays a critical role in the exciton VC, while affecting VP less. For different monolayer samples with disorder characterized by their Stokes shift (SS), VC decreases in samples with higher SS while VP does not follow a simple trend. These two methods consistently demonstrate that VC as defined by the degree of linearly polarized photoluminescence is more sensitive to disorder, motivating further theoretical studies.

Integrating factors and conservation theorems for Hamilton's canonical equations of motion of variable mass nonholonomic nonconservative dynamical systems

Institute of Scientific and Technical Information of China (English)

李仁杰; 乔永芬; 刘洋

2002-01-01

We present a general approach to the construction of conservation laws for variable mass nonholonomic noncon-servative systems. First, we give the definition of integrating factors, and we study in detail the necessary conditionsfor the existence of the conserved quantities. Then, we establish the conservation theorem and its inverse theorem forHamilton's canonical equations of motion of variable mass nonholonomic nonconservative dynamical systems. Finally,we give an example to illustrate the application of the results.

The Role of Source Material in Basin Sedimentation, as Illustrated within Eureka Valley, Death Valley National Park, CA.

Science.gov (United States)

Lawson, M. J.; Yin, A.; Rhodes, E. J.

2015-12-01

Steep landscapes are known to provide sediment to sink regions, but often petrological factors can dominate basin sedimentation. Within Eureka Valley, in northwestern Death Valley National Park, normal faulting has exposed a steep cliff face on the western margin of the Last Chance range with four kilometers of vertical relief from the valley floor and an angle of repose of nearly 38 degrees. The cliff face is composed of Cambrian limestone and dolomite, including the Bonanza King, Carrara and Wood Canyon formations. Interacting with local normal faulting, these units preferentially break off the cliff face in coherent blocks, which result in landslide deposits rather than as finer grained material found within the basin. The valley is well known for a large sand dune, which derives its sediment from distal sources to the north, instead of from the adjacent Last Chance Range cliff face. During the Holocene, sediment is sourced primary from the northerly Willow Wash and Cucomungo canyon, a relatively small drainage (less than 80 km2) within the Sylvan Mountains. Within this drainage, the Jurassic quartz monzonite of Beer Creek is heavily fractured due to motion of the Fish Valley Lake - Death Valley fault zone. Thus, the quartz monzonite is more easily eroded than the well-consolidated limestone and dolomite that forms the Last Change Range cliff face. As well, the resultant eroded material is smaller grained, and thus more easily transported than the limestone. Consequently, this work highlights an excellent example of the strong influence that source material can have on basin sedimentation.

Direct oral anticoagulants for treatment of HIT: update of Hamilton experience and literature review.

Science.gov (United States)

Warkentin, Theodore E; Pai, Menaka; Linkins, Lori-Ann

2017-08-31

Direct oral anticoagulants (DOACs) are attractive options for treatment of heparin-induced thrombocytopenia (HIT). We report our continuing experience in Hamilton, ON, Canada, since January 1, 2015 (when we completed our prospective study of rivaroxaban for HIT), using rivaroxaban for serologically confirmed HIT (4Ts score ≥4 points; positive platelet factor 4 [PF4]/heparin immunoassay, positive serotonin-release assay). We also performed a literature review of HIT treatment using DOACs (rivaroxaban, apixaban, dabigatran, edoxaban). We focused on patients who received DOAC therapy for acute HIT as either primary therapy (group A) or secondary therapy (group B; initial treatment using a non-DOAC/non-heparin anticoagulant with transition to a DOAC during HIT-associated thrombocytopenia). Our primary end point was occurrence of objectively documented thrombosis during DOAC therapy for acute HIT. We found that recovery without new, progressive, or recurrent thrombosis occurred in all 10 Hamilton patients with acute HIT treated with rivaroxaban. Data from the literature review plus these new data identified a thrombosis rate of 1 of 46 patients (2.2%; 95% CI, 0.4%-11.3%) in patients treated with rivaroxaban during acute HIT (group A, n = 25; group B, n = 21); major hemorrhage was seen in 0 of 46 patients. Similar outcomes in smaller numbers of patients were observed with apixaban (n = 12) and dabigatran (n = 11). DOACs offer simplified management of selected patients, as illustrated by a case of persisting (autoimmune) HIT (>2-month platelet recovery with inversely parallel waning of serum-induced heparin-independent serotonin release) with successful outpatient rivaroxaban management of HIT-associated thrombosis. Evidence supporting efficacy and safety of DOACs for acute HIT is increasing, with the most experience reported for rivaroxaban. © 2017 by The American Society of Hematology.

Nanostructured metal oxides: promise opportunity and challenge to develop clinically useful 99Mo/99mTc generators using (n, gamma)99Mo

International Nuclear Information System (INIS)

Dash, Ashutosh

2014-01-01

The role of 99m Tc diagnostic nuclear medicine needs hardly to be reiterated. Today, it is the most widely used radionuclide for single photon emission computed tomography (SPECT) imaging procedures. The current strategy of availing 99m Tc is ensured from column chromatographic 99 Mo/ 99m Tc generators using a bed of acidic alumina. While the column chromatographic 99 Mo/ 99m Tc generator constitute a successful exemplar of availing 99m Tc, the limited capacity of alumina (2-20 mg Mo per g of alumina) for taking up molybdate ions necessitates the use of 99 Mo of the highest specific activity available, as can be found in fission produced 99 Mo (F 99 Mo). In order to reduce dependence of F 99 Mo, the scope of using low specific activity (n,γ) 99 Mo along with high capacity adsorbent is an interesting prospect. In this context, the scope of using nanomaterials as a viable adsorbent seemed attractive by virtue of their huge surface to volume ratios, altered physical properties, tailored surface chemistry, favorable adsorption characteristics, and enhanced surface reactivity resulting from the nanoscale dimensions. This emerging class of adsorbent represents an innovative paradigm and is expected to play an important role in the development of 99 Mo/ 99m Tc generators adaptable to the existing and foreseeable demands. This talk outlines a critical assessment on the role of nanostructured metal oxides, recent developments, the contemporary status, and key challenges and apertures to the near future. (author)

Antifan activism as a response to MTV's The Valleys

Directory of Open Access Journals (Sweden)

Bethan Jones

2015-06-01

Full Text Available MTV has launched several reality TV shows in the United Kingdom, but one, The Valleys (2012–14, about youth moving from the South Wales Valleys to Cardiff, has received much criticism. Grassroots criticism of the show arose, and a Valleys-centric campaign, The Valleys Are Here, took direct action. I adopt Jonathan Gray's definition of antifans to complicate ideas of fan activism. I utilize comments and posts made on the Valleys Are Here Twitter feed and Facebook account, as well as the organization's Web site, to examine the ways in which they encourage activism among antifans of the series. I pay particular attention to activist calls for MTV to be held accountable for its positioning of Wales and the Valleys, and to how it encourages participation among varied groups of people whose common denominator is their dislike of the series. Fan activism is not exclusive to people who consider themselves fans, and notions of fan activism can be complicated by drawing in antifans.

1980-81 Graduate Student Survey. AIP Report.

Science.gov (United States)

Ellis, Susanne D.

Results of the 1980-81 Graduate Student Survey of physics and astronomy students are presented. Information is presented on the following: employment offers for new physics masters and doctorate recipients, 1976-81; characteristics of the graduate physics student population, 1980-81, including sex, citizenship, professional society membership,…

[«I stole with my eyes»: Hamilton Naki, a pioneer in heart transplantation].

Science.gov (United States)

López-Valdés, Julio César

On December 2, 1967, when Denise Darvall was hit by a car, a surgery that made medical history was unfold: Hamilton Naki, a black man, expertly removed her heart and gave it to Christian Barnard, who was preparing the receptor, Louis Washkansky, in an adjacent operating room. Naki's contribution was an outlaw act, a criminal offense under the laws of apartheid due to the difference of races; the law forbade him to cut white meat or touch white blood. Naki was perhaps the second most important man in the team that day. There were few photographs where he and Barnard appeared together, but because of the nature of society was Barnard who won the world's attention.

Decay of 99Mo

International Nuclear Information System (INIS)

Dickens, J.K.; Love, T.A.

1976-01-01

Relative intensities for K x-rays and gamma rays emanating from 99 Mo in equilibrium with its 99 Tc* daughter have been measured using several Ge photon detectors. Combining these intensities with an evaluated set of electron-conversion coefficients has provided a set of absolute intensities for the observed gamma rays. The absolute intensity for the dominant 140.5-keV gamma ray in 99 Tc was determined to be 90.7 +- 0.6/100 99 Mo disintegrations for 99 Mo decay in equilibrium with decay of the 99 Tc* daughter

The quasi-steady state of the valley wind system

Directory of Open Access Journals (Sweden)

Juerg eSchmidli

2015-12-01

Full Text Available The quasi-steady-state limit of the diurnal valley wind system is investigated overidealized three-dimensional topography. Although this limit is rarely attained inreality due to ever-changing forcings, the investigation of this limit canprovide valuable insight, in particular on the mass and heat fluxes associatedwith the along-valley wind. We derive a scaling relation for the quasi-steady-state along-valleymass flux as a function of valley geometry, valley size, atmospheric stratification,and surface sensible heat flux forcing. The scaling relation is tested by comparisonwith the mass flux diagnosed from numerical simulations of the valleywind system. Good agreement is found. The results also provide insight into the relationbetween surface friction and the strength of the along-valley pressure gradient.

Direct measurement of exciton valley coherence in monolayer WSe2

KAUST Repository

Hao, Kai

2016-02-29

In crystals, energy band extrema in momentum space can be identified by a valley index. The internal quantum degree of freedom associated with valley pseudospin indices can act as a useful information carrier, analogous to electronic charge or spin. Interest in valleytronics has been revived in recent years following the discovery of atomically thin materials such as graphene and transition metal dichalcogenides. However, the valley coherence time—a crucial quantity for valley pseudospin manipulation—is difficult to directly probe. In this work, we use two-dimensional coherent spectroscopy to resonantly generate and detect valley coherence of excitons (Coulomb-bound electron–hole pairs) in monolayer WSe₂ (refs ,). The imposed valley coherence persists for approximately one hundred femtoseconds. We propose that the electron–hole exchange interaction provides an important decoherence mechanism in addition to exciton population recombination. This work provides critical insight into the requirements and strategies for optical manipulation of the valley pseudospin for future valleytronics applications.

Comparative study of {sup 99}Mo/{sup 99m}Tc generators at base of synthesized gels starting from activation and fission {sup 99}Mo; Estudio comparativo de generadores {sup 99}Mo/{sup 99m}Tc a base de geles sintetizados a partir de {sup 99}Mo de activacion y de fision

Energy Technology Data Exchange (ETDEWEB)

Lopez M, I Z [UAEM, Paseo Colon esq. Paseo Tollocan, 50120 Toluca, Estado de Mexico (Mexico); Monroy G, F; Rivero G, T; Rojas N, P [ININ, Carretera Mexico -Toluca S/N, 52045 La Marquesa Ocoyoacac, Estado de Mexico (Mexico)

2007-07-01

The {sup 99m}Tc is used for diagnostic and therapy. It is produced starting from {sup 99}Mo, absorbed in chromatographic columns, loaded with alumina that absorb only 0.2% of {sup 99}Mo with high specific activities of {sup 99}Mo, obtained from the {sup 235}U fission. Given these conditions and limitations, new preparation procedures of {sup 99}Mo/{sup 99m}Tc generators, its have been developed, using zirconium molybdates gels that incorporates until 30% of {sup 99}Mo, conserve similar characteristics of quality and purity that the traditional generator. The radiochemical characteristics of the {sup 99m}Tc elution, depend strongly on the gel preparation conditions. In particular, the present work has by object to determine the influence of the {sup 99}Mo used type, fission or activation product, during the gels synthesis, as well as the used air flow for the agitation in the gels preparation and its influence in the {sup 99}Mo/{sup 99m}Tc generators quality. When diminishing the flow of agitation air the efficiency it increases and in the radionuclide purity of the eluates and when using {sup 99}Mo from fission for the gels production it increases in an important way the elutriation efficiency, the radiochemical and radionuclide purity of the {sup 99m}Tc eluates. (Author)

Results of regular study on radionuclidic purity of sup(99m)Tc obtained from 99Mo-sup(99m)Tc generators

International Nuclear Information System (INIS)

Vlcek, J.; Rohacek, J.; Husak, V.

1979-01-01

A total of 39 sup(99m)Tc eluates obtained from 9 99 Mo-sup(99m)Tc generators delivered by The Radiochemical Centre Amersham during one year was studied with regard to their radionuclide purity. Using a Ge(Li) spectrometer the contaminants 60 Co, 103 Ru, 131 I, 134 Cs, 140 La and 188 Re were found in sup(99m)Tc-eluates with average levels ranging from 2.9 x 10 -3 to 2.8 x 10 -1 per cent of sup(99m)Tc activity. The additional total body absorbed dose caused by these contaminants, as calculated from their average content in sup(99m)Tc eluates, was less than 1% of the dose due to sup(99m)Tc pertechnetate. (orig.) 891 MG/orig. 892 CS [de

Photon wavelength dependent valley photocurrent in multilayer MoS2

Science.gov (United States)

Guan, Hongming; Tang, Ning; Xu, Xiaolong; Shang, LiangLiang; Huang, Wei; Fu, Lei; Fang, Xianfa; Yu, Jiachen; Zhang, Caifeng; Zhang, Xiaoyue; Dai, Lun; Chen, Yonghai; Ge, Weikun; Shen, Bo

2017-12-01

The degree of freedom (DOF) of the K (K') valley in transition-metal dichalcogenides, especially molybdenum disulfide (MoS2), offers an opportunity for next-generation valleytronics devices. In this work, the K (K') valley DOF of multilayer MoS2 is studied by means of the photon wavelength dependent circular photogalvanic effect (CPGE) at room temperature upon a strong external out-of-plane electric field induced by an ionic liquid (IL) gate, which breaks the spatial-inversion symmetry. It is demonstrated that only on resonant excitations in the K (K') valley can the valley-related CPGE signals in multilayer MoS2 with an IL gate be detected, indicating that the valley contrast is indeed regenerated between the K and K' valleys when the electric field is applied. As expected, it can also be seen that the K (K') valley DOF in multilayer MoS2 can be modulated by the external electric field. The observation of photon wavelength dependent valley photocurrent in multilayer MoS2, with the help of better Ohmic contacts, may pave a way for optoelectronic applications of valleytronics in the future.

Tygerberg Hospital, 1980

African Journals Online (AJOL)

haematocrit, cord bilirubin, number of liveborn babies, birth weight, neonatal death, hyaline membrane disease .... report the outcome of babies of mothers with severe. Rh disease treated at Tygerberg Hospital since 1980 by ..... Walker W. Haemolytic disease of the newborn. In: Gairdner D, Hull 0, eds. Recent Advances iD ...

Annual report 1980

International Nuclear Information System (INIS)

1981-06-01

The report reviews the activities of the BAM departments for - metals and metal constructions - building construction - organic materials - chemical safety engineering - special fields of materials testing - processes independent of materials and of its technical and scientific services. The second part contains general information and statistics for 1980. (RW) [de

Radionuclidic contamination of 99Mo, 131I and 103Ru in the eluate of 99Mo-99mTc chromatographic generator: comparision on fission produced 99Mo from RPC, Nordio and ARI

International Nuclear Information System (INIS)

Soenarjo, Sunarhadijoso; Gunawan, Adang Hardi

1996-01-01

The 99 Mo- 99m Tc Chromatographic generators is the most popular system to provide 99m Tc medical radioisotope. Radioisotope Production Centre (RPC)- BATAN has routinely produced the generator loaded with 99 Mo prepared by 235 U fission. By using fission produced 99 Mo, the resulting 99m Tc is potentially contaminated by other fission products which are difficult to eliminate completely. In order to study the characteristic of the generator and radionuclidic impurity pattern of the 99m Tc eluates, an evaluation of gamma spectrometric determination has been carried out. The bulk solutions of 99 Mo produced by RPC BATAN (Indonesia), Nordion (Canada) and ARI (Australia) were loaded to generators manufactured between July 1993 to May 1994. The saline-eluate 99m Tc, in a total volume of 10 ml each, was subjected to gamma spectrometric determination. The radiation of 99m Tc was eliminated by lead shield of 0.6913 cm thickness. The 99m Tc yield fluctuation from 28 generators indicated that the characteristics of the generator columns were very good. The 99m Tc eluates were consistently contaminated by 99 Mo, 131 I and 103 Ru, although the contamination level in all cases did not exceed the maximum permissible levels. The fluctuation of radionuclidic impurities were probably caused by variation in the irradiation parameter or by variation in the 99 Mo separation methods. (author), 23 refs, 1 tab, 3 figs

Spin-valley splitting of electron beam in graphene

Directory of Open Access Journals (Sweden)

Yu Song

2016-11-01

Full Text Available We study spatial separation of the four degenerate spin-valley components of an electron beam in a EuO-induced and top-gated ferromagnetic/pristine/strained graphene structure. We show that, in a full resonant tunneling regime for all beam components, the formation of standing waves can lead sudden phase jumps ∼−π and giant lateral Goos-Hänchen shifts as large as the transverse beam width, while the interplay of the spin and valley imaginary wave vectors in the modulated regions can lead differences of resonant angles for the four spin-valley flavors, manifesting a spin-valley beam splitting effect. The splitting effect is found to be controllable by the gating and strain.

99mTc-MDP scintigraphy of femoral head necrosis following femoral neck fracture

International Nuclear Information System (INIS)

Lee, Soon Jin; Lee, Jun Hyung; Kim, Eun Kyung; Lee, Sun Wha; Kim, Soon Yong

1985-01-01

Secondary ischemic necrosis of femoral head due to loss of blood supply following to femoral neck fracture is well known. The regional distribution of bone-seeking radiopharmaceuricals in the skeleton can depend on a number of factors, but bone blood flow is a major physiological determinant of regional skeletal uptake of Tc-99m polyphosphate and bone imaging may thus be used for the evaluation of vascularity of the femoral head. The authors made a comparative study of scintigraphic findings and operative findings of 28 cases of femoral neck fracture treated at Kyung Hee University Hospital from April 1980 to May 1984. The results were as follows: 1. In 16 cases of proven avascular necorsis of femoral head, scintigraphy showed absent or decreased activity in 14 cases (87.5%), while radiography showed increased density in 10 cases (62.5%). 2. In 12 cases of proven vital femoral head, scintigraphy showed increased activity in 9 cases (75%) and radiography showed decreased density in 9 cases (75%). 3. 99mTc-MDP scintigraphy was an excellent and useful method for assessing bone vitality of femoral head

The carbon stable isotope biogeochemistry of streams, Taylor Valley, Antarctica

International Nuclear Information System (INIS)

Lyons, W.B.; Leslie, D.L.; Harmon, R.S.; Neumann, K.; Welch, K.A.; Bisson, K.M.; McKnight, D.M.

2013-01-01

Highlights: ► δ 13 C-DIC reported from McMurdo Dry Valleys, Antarctica, streams. ► Stream water δ 13 C PDB values range −9.4‰ to +5.1‰, largely inorganic in character. ► Atmospheric exchange is the dominant control on δ 13 C-DIC. - Abstract: The McMurdo Dry Valleys region of Antarctica is the largest ice-free region on the continent. This study reports the first C stable isotope measurements for dissolved inorganic C present in ephemeral streams in four dry valleys that flow for four to twelve weeks during the austral summer. One of these valleys, Taylor Valley, has been the focus of the McMurdo Dry Valleys Long-Term Ecological Research (MCM-LTER) program since 1993. Within Taylor Valley, numerous ephemeral streams deliver water to three perennially ice-covered, closed-basin lakes: Lake Fryxell, Lake Hoare, and Lake Bonney. The Onyx River in the Wright Valley, the longest river in Antarctica, flows for 40 km from the Wright Lower Glacier and Lake Brownworth at the foot of the glacier to Lake Vanda. Streamflow in the McMurdo Dry Valley streams is produced primarily from glacial melt, as there is no overland flow. However, hyporheic zone exchange can be a major hydrogeochemical process in these streams. Depending on landscape position, these streams vary in gradient, channel substrate, biomass abundance, and hyporheic zone extent. This study sampled streams from Taylor, Wright, Garwood, and Miers Valleys and conducted diurnal sampling of two streams of different character in Taylor Valley. In addition, transect sampling was undertaken of the Onyx River in Wright Valley. The δ 13 C PDB values from these streams span a range of greater than 14‰, from −9.4‰ to +5.1‰, with the majority of samples falling between −3‰ and +2‰, suggesting that the C stable isotope composition of dissolved C in McMurdo Dry Valley streams is largely inorganic in character. Because there are no vascular plants on this landscape and no groundwater input to these

Annex to the annual report 1980

International Nuclear Information System (INIS)

This second volume entitled 'Annex to Annual Report' deals in more detail with the scientific work of the ILL. College 2: the Scientific activity of theoricians at the ILL for 1980 is described. College 3 to college 9: experimental reports giving details on the experiments performed at Institut Laue Langevin (ILL) in 1980 have been compiled. They are published here under their proposal number within the classification. Scheme in use at the I.L.L

'99Mo/99mTc Generator Based on High Radionuclidic Pure Zirconium Molybdate Gel

International Nuclear Information System (INIS)

Amin, M.; Mostafa, M.; El-Amir, M.A.; El-Absy, M.A.; Mohamed, O.I.; Farag, A.B.

2014-01-01

99 Mo / 99 mTc radioisotope generator was prepared using in-situ precipitated zirconium molybdate chromatographic column. Zirconium molybdate gel matrix was synthesized by precipitation of neutron activation molybdenum-99 from its solution after variety purification processes to prevent contamination of the 99m Tc eluate with cross-contaminants. Greeter than 82.7 ± 0.4 % of the generated 99m Tc was immediately and reproducible eluted by passing 10 ml 0.9 % NaCl solution through the 1 g zirconium molybdate- 99 Mo column matrix at a flow rate of 0.5 ml / min and room temperature with high chemical, radionuclide ( ≥ 99.9 % 99m Tc) and radiochemical purity ( ≥ 97.7 % % as 99 mTcO 4 - ) with ph value suitable for medical uses.

Magnesium-Molybate Compounds as Matrix for 99Mo/99mTc Generators

Directory of Open Access Journals (Sweden)

Fabiola Monroy-Guzman

2011-01-01

Full Text Available This work reports the preparation of a 99mTc generator based on conversion of 99Mo produced by neutron irradiation, into insoluble magnesium 99Mo-molybdates compounds as matrix. The effect of magnesium salt types and concentration, Mg:Mo molar ratios, pH of molybdate solutions, eluate volume as well as the addition order of molybdate and magnesium solutions’ influences on the final 99mTc were evaluated. Polymetalates and polymolybdates salts either crystallized or amorphous were obtained depending on the magnesium salt and Mg:Mo molar ratio used in matrix preparation. 99Mo/99mTc generator production based on magnesium-99Mo molybdate compounds allow reduction of preparation time and eliminates the use of specialized installations. The best generator performances were attained using matrices prepared from 0.1 mol/L MgCl2·6H2O solutions, ammonium molybdate solutions at pH 7 and at a Mg:Mo molar ratio of 1:1.

Assessing Drought Impacts on Water Storage using GRACE Satellites and Regional Groundwater Modeling in the Central Valley of California

Science.gov (United States)

Scanlon, B. R.; Zhang, Z.; Save, H.; Faunt, C. C.; Dettinger, M. D.

2015-12-01

Increasing concerns about drought impacts on water resources in California underscores the need to better understand effects of drought on water storage and coping strategies. Here we use a new GRACE mascons solution with high spatial resolution (1 degree) developed at the Univ. of Texas Center for Space Research (CSR) and output from the most recent regional groundwater model developed by the U.S. Geological Survey to evaluate changes in water storage in response to recent droughts. We also extend the analysis of drought impacts on water storage back to the 1980s using modeling and monitoring data. The drought has been intensifying since 2012 with almost 50% of the state and 100% of the Central Valley under exceptional drought in 2015. Total water storage from GRACE data declined sharply during the current drought, similar to the rate of depletion during the previous drought in 2007 - 2009. However, only 45% average recovery between the two droughts results in a much greater cumulative impact of both droughts. The CSR GRACE Mascons data offer unprecedented spatial resolution with no leakage to the oceans and no requirement for signal restoration. Snow and reservoir storage declines contribute to the total water storage depletion estimated by GRACE with the residuals attributed to groundwater storage. Rates of groundwater storage depletion are consistent with the results of regional groundwater modeling in the Central Valley. Traditional approaches to coping with these climate extremes has focused on surface water reservoir storage; however, increasing conjunctive use of surface water and groundwater and storing excess water from wet periods in depleted aquifers is increasing in the Central Valley.

Hydrology of the Ferron sandstone aquifer and effects of proposed surface-coal mining in Castle Valley, Utah, with sections on stratigraphy and leaching of overburden

Science.gov (United States)

Lines, Gregory C.; Morrissey, Daniel J.; Ryer, Thomas A.; Fuller, Richard H.

1983-01-01

Coal in the Ferron Sandstone Member of the Mancos Shale of Cretaceous age has traditionally been mined by underground techniques in the Emery Coal Field in the southern end of Castle Valley in east-central Utah. However, approximately 99 million tons are recoverable by surface mining. Ground water in the Ferron is the sole source of supply for the town of Emery, but the aquifer is essentially untapped outside the Emery area.The Ferron Sandstone Member crops out along the eastern edge of Castle Valley and generally dips 2 ? to 10 ? to the northwest. Sandstones in the Ferron are enclosed between relatively impermeable shale in the Tununk and Blue Gate Members of the Mancos Shale. Along the outcrop, the Ferron ranges in thickness from about 80 feet in the northern part of Castle Valley to 850 feet in the southern part. The Ferron also generally thickens in the subsurface downdip from the outcrop. Records from wells and test holes indicate that the full thickness of the Ferron is saturated with water in most areas downdip from the outcrop area.Tests in the Emery area indicate that transmissivity of the Ferron sandstone aquifer ranges from about 200 to 700 feet squared per day where the Ferron is fully saturated. Aquifer transmissivity is greatest near the Paradise Valley-Joes Valley fault system where permeability has been increased by fracturing. Storage coefficient ranges from about 10 .6 to 10 -3 where the Ferron sandstone aquifer is confined and probably averages 5 x 10-2 where it is unconfined.

Hamilton's equations for a fluid membrane

Energy Technology Data Exchange (ETDEWEB)

Capovilla, R [Departamento de Fisica, Centro de Investigacion y de Estudios Avanzados, Apdo. Postal 14-740, 07000 Mexico, DF (Mexico); Guven, J [Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, Apdo. Postal 70-543, 04510 Mexico, DF (Mexico); Rojas, E [Facultad de Fisica e Inteligencia Artificial, Universidad Veracruzana, 91000 Xalapa, Veracruz (Mexico)

2005-10-14

Consider a homogeneous fluid membrane described by the Helfrich-Canham energy, quadratic in the mean curvature of the membrane surface. The shape equation that determines equilibrium configurations is fourth order in derivatives and cubic in the mean curvature. We introduce a Hamiltonian formulation of this equation which dismantles it into a set of coupled first-order equations. This involves interpreting the Helfrich-Canham energy as an action; equilibrium surfaces are generated by the evolution of space curves. Two features complicate the implementation of a Hamiltonian framework. (i) The action involves second derivatives. This requires treating the velocity as a phase-space variable and the introduction of its conjugate momentum. The canonical Hamiltonian is constructed on this phase space. (ii) The action possesses a local symmetry-reparametrization invariance. The two labels we use to parametrize points on the surface are themselves physically irrelevant. This symmetry implies primary constraints, one for each label, that need to be implemented within the Hamiltonian. The two Lagrange multipliers associated with these constraints are identified as the components of the acceleration tangential to the surface. The conservation of the primary constraints implies two secondary constraints, fixing the tangential components of the momentum conjugate to the position. Hamilton's equations are derived and the appropriate initial conditions on the phase-space variables are identified. Finally, it is shown how the shape equation can be reconstructed from these equations.

Radionuclide Basics: Technetium-99

Science.gov (United States)

Technetium-99 (chemical symbol Tc-99) is a silver-gray, radioactive metal. It occurs naturally in very small amounts in the earth's crust, but is primarily man-made. Technetium-99m is a short-lived form of Tc-99 that is used as a medical diagnostic tool.

99Mo-99mTc generator - study of their performance and quality

International Nuclear Information System (INIS)

Acar, M.E.D.

1987-01-01

In this work the performance of the 99 Mo - 99m Tc generators produced at IPEN-CNEN/SP as well as the quality of the eluted solutions were analysed. The following parameters were studied: elution efficiency, chemical radiochemical, radionuclidic and microbiological purities and pH of the eluates. The 99m Tc yield ranged from 84,7 to 98,5%. The radioactivity due to the pertechnetate ion in the studied solutions was higher than 97,5%. The aluminium content in eluates, determined by spectrophotometry, was lower than 2,5 μg/ml and the pH of the solutions between 4,5 and 5,1. Radioactive impurities of the order of 10 -3 KBq 99 Mc/MBq 99m Tc and 10 -5 KBq 131 I/MBq 99m Tc were found in the eluates at the time of elution. Other γ emitting radioactive impurities were order of 10 -3 KBq/MBq 99m Tc. The eluates were sterile and pyrogen-free. From the results obtained in this work one can state that the IPEN-TEC generator is a reliable source of good quality 99m Tc-pertechnetate. (author) [pt

Research report 1980

International Nuclear Information System (INIS)

1981-01-01

This research report for 1980 of the Department of Nuclear Science and Technology of the Royal Naval College, Greenwich contains sections covering work on nuclear marine technology, space-borne instrumentation and computing. Conferences and seminars held and also attended by members of staff are given. Publications are listed. (U.K.)

The thermal regime in the resurgent dome of Long Valley Caldera, California: Inferences from precision temperature logs in deep wells

Science.gov (United States)

Hurwitz, S.; Farrar, C.D.; Williams, C.F.

2010-01-01

Long Valley Caldera in eastern California formed 0.76Ma ago in a cataclysmic eruption that resulted in the deposition of 600km3 of Bishop Tuff. The total current heat flow from the caldera floor is estimated to be ~290MW, and a geothermal power plant in Casa Diablo on the flanks of the resurgent dome (RD) generates ~40MWe. The RD in the center of the caldera was uplifted by ~80cm between 1980 and 1999 and was explained by most models as a response to magma intrusion into the shallow crust. This unrest has led to extensive research on geothermal resources and volcanic hazards in the caldera. Here we present results from precise, high-resolution, temperature-depth profiles in five deep boreholes (327-1,158m) on the RD to assess its thermal state, and more specifically 1) to provide bounds on the advective heat transport as a guide for future geothermal exploration, 2) to provide constraints on the occurrence of magma at shallow crustal depths, and 3) to provide a baseline for future transient thermal phenomena in response to large earthquakes, volcanic activity, or geothermal production. The temperature profiles display substantial non-linearity within each profile and variability between the different profiles. All profiles display significant temperature reversals with depth and temperature gradients <50??C/km at their bottom. The maximum temperature in the individual boreholes ranges between 124.7??C and 129.5??C and bottom hole temperatures range between 99.4??C and 129.5??C. The high-temperature units in the three Fumarole Valley boreholes are at the approximate same elevation as the high-temperature unit in borehole M-1 in Casa Diablo indicating lateral or sub-lateral hydrothermal flow through the resurgent dome. Small differences in temperature between measurements in consecutive years in three of the wells suggest slow cooling of the shallow hydrothermal flow system. By matching theoretical curves to segments of the measured temperature profiles, we calculate

99Mo production by 100Mo(n,2n)99Mo using accelerator neutrons

International Nuclear Information System (INIS)

Sato, Nozomi; Kawabata, Masako; Nagai, Yasuki; Hashimoto, Kazuyuki; Hatsukawa, Yuichi; Saeki, Hideya; Motoishi, Shoji; Kin, Tadahiro; Konno, Chikara; Ochiai, Kentaro; Takakura, Kosuke; Minato, Futoshi; Iwamoto, Osamu; Iwamoto, Nobuyuki; Hashimoto, Shintaro

2013-01-01

We proposed a new route to produce a medical radioisotope 99 Mo by the 100 Mo(n,2n) 99 Mo reaction using accelerator neutrons. A high-quality 99 Mo with a minimum level of radioactive waste can be obtained by the proposed reaction. The decay product of 99 Mo, 99m Tc, is separated from 99 Mo by the sublimation method. The proposed route could bring a major breakthrough in the solution of ensuring a constant and reliable supply of 99 Mo. (author)

"Peintre de Sa Majesté Britannique". Franz Adolph of Freenthal and his portrait of Maximilian Hamilton, Prince-Bishop of Olomouc

Directory of Open Access Journals (Sweden)

Suchánek, Pavel

2012-09-01

Full Text Available This essay examines the portrait of Maximilian von Hamilton (1714-1776, the last Prince-Bishop of Olomouc/Olmütz, painted between 1769 and 1772 by Franz Adolph of Freenthal (1721-1773, a former painter to the British royal court. The study focuses in turn on three visual motifs in Hamilton's portrait: the rhetorical gestures of the sitter, his attire and the way he is depicted, and the form of presentation and the function of the painting in the ceremonial space of the princely residence. In examining each of these motifs, account is taken of the specific visual conventions applied in this genre, and of the contemporary rules of visual rhetoric. By referencing the classical motif of modesty and moderation from antiquity, Adolph underlined the importance of the ideal of antiquity and with it "natural" speech and behaviour. He attempted to express the spirit of antiquity by comparing contemporary clothing and rhetorical gestures to those of the orators or other public figures of antiquity. In a similar way to contemporary British painters, he thus referenced models taken from antiquity, with the aim of evoking a noble past and representing the ideal of the virtue of antiquity.

Valley-polarized quantum transport generated by gauge fields in graphene

DEFF Research Database (Denmark)

Settnes, Mikkel; Garcia, Jose H; Roche, Stephan

2017-01-01

We report on the possibility to simultaneously generate in graphene a bulk valley-polarized dissipative transport and a quantum valley Hall effect by combining strain-induced gauge fields and real magnetic fields. Such unique phenomenon results from a ‘resonance/anti-resonance’ effect driven by t...... Kubo transport methods combined with a valley projection scheme to access valley-dependent conductivities and show that the results are robust against disorder....

Quality control studies of 99Mo used in 99Mo/99mTc generators produced at IPEN/CNEN-SP, Brazil

International Nuclear Information System (INIS)

Said, Daphne S.; Brambilla, Tania P.; Matsuda, Margareth M.N.; Osso Junior, Joao A.

2015-01-01

99m Tc is the most used radionuclide in nuclear medicine. In Brazil, the 99 Mo/ 99m Tc generators are produced exclusively by the Center of Radiopharmacy at IPEN-CNEN/SP, by importing 99 Mo from different suppliers. 99 Mo (t 1/2 = 66 h) is a fission product of 235 U, therefore, it can be accompanied by several radioisotopes that are highly prejudicial for human health, demanding a strict quality control of this product for generators safe use. The European Pharmacopoeia established some parameters and limits that evaluate the quality of the solution of sodium [ 99 Mo]molybdate, that is used as raw material for generator's production. The European Pharmacopoeia also recommends some analytical methods to perform these evaluations, however, it has been observed difficulties on the implementation of these methods by the generator's producers. These difficulties are probably related to the lack of practicability of the proposed methods and the extensive list of utilized reagents. In this work some procedures of the European Pharmacopoeia's quality control method for 99 Mo were evaluated. Different types of solid phase exchanger cartridges were tested for retention of 99 Mo in 3 different conditions. Cartridges that presented percentages of retention higher than 90% were also tested for separation of 99 Mo from possible contaminants (Ru e Te). The results shown that solid phase exchanger cartridges that presented percentages of retention of Mo higher than 90% also presented significant percentages of retention of Ru and Te. An alternative method for separation of 99 Mo from 131 I (other contaminant) are also proposed. (author)

Electrical control of the anomalous valley Hall effect in antiferrovalley bilayers

Science.gov (United States)

Tong, Wen-Yi; Duan, Chun-Gang

2017-08-01

In analogy to all-electric spintronics, all-electric valleytronics, i.e., valley manipulation via electric means, becomes an exciting new frontier as it may bring revolutions in the field of data storage with ultra-high speed and ultra-low power consumption. The existence of the anomalous valley Hall effect in ferrovalley materials demonstrates the possibility of electrical detection for valley polarization. However, in previously proposed valley-polarized monolayers, the anomalous valley Hall effect is controlled by external magnetic fields. Here, through elaborate structural design, we propose the antiferrovally bilayer as an ideal candidate for realizing all-electric valleytronic devices. Using the minimal k.p model, we show that the energy degeneracy between valley indexes in such system can be lifted by electric approaches. Subsequently, the anomalous valley Hall effect strongly depends on the electric field as well. Taking the bilayer VSe2 as an example, all-electric tuning and detecting of anomalous valley Hall effect is confirmed by density-functional theory calculations, indicating that the valley information in such antiferrovalley bilayer can be reversed by an electric field perpendicular to the plane of the system and easily probed through the sign of the Hall voltage.

49 CFR 1242.33 - Other expenses and casualties and insurance (accounts XX-17-99, XX-18-99, XX-19-99, 50-17-00, 50...

Science.gov (United States)

2010-10-01

... (accounts XX-17-99, XX-18-99, XX-19-99, 50-17-00, 50-18-00, and 50-19-00). 1242.33 Section 1242.33....33 Other expenses and casualties and insurance (accounts XX-17-99, XX-18-99, XX-19-99, 50-17-00, 50... separation of administrative—other (account XX-19-06). Operating Expenses—Equipment locomotives ...

Superfund Record of Decision (EPA Region 9): North Hollywood/Burbank Well Field Area 1, San Fernando Valley Site, California (first remedial action), September 1987. Final report

Energy Technology Data Exchange (ETDEWEB)

1987-09-24

The North Hollywood - Burbank Well Field (NHBWF) is located within the San Fernando Valley Ground Water basin, which can provide drinking water for approximately 500,000 people residing in the San Fernando Valley and Los Angeles. In 1980 TCE and PCE were discovered in 25% of DWP's wells. In July 1981, DWP and the Southern California Association of Governments began a two-year study funded by EPA. The study revealed the occurrence of ground-water contamination plume patterns that are spreading toward the southeast. The primary contaminant of concern to the ground-water is TCE with PCE and other VOCs present. The selected remedial action for the site is ground-water pump and treatment using aeration and granular-activated-carbon - air-filtering units, with discharge to the DWP Pumping Station for chlorination and distribution. Spent carbon will be removed and replaced with fresh carbon, with the spent carbon scheduled either for disposal or regeneration. The estimated capital cost for this remedial action is $2,192,895 with present worth OandM of $2,284,105.

Outbreak of salmonellosis associated with consumption of pulled pork at a church festival - Hamilton County, Ohio, 2010.

Science.gov (United States)

2014-01-03

On June 18, 2010, Hamilton County Public Health (HCPH), a local health department in Ohio, began receiving reports of gastrointestinal illness from persons who attended a church festival held during June 11-13 in a suburban community of Hamilton County. HCPH investigated and confirmed the existence of a foodborne outbreak associated with consumption of pulled pork prepared in a private home and sold at the church festival. Sixty-four attendees with gastroenteritis were identified. Salmonella enterica serotype Typhimurium (Salmonella Typhimurium) was found in stool specimens from three patients; no other pathogen was found. Because the outbreak was identified after the church festival had concluded, the environmental investigation was limited to interviews of food handlers. The primary public health interventions consisted of 1) active surveillance for additional cases of salmonellosis associated with the festival, 2) consultation with the festival organizers and food vendors to ensure the pork product was not resold or consumed elsewhere, 3) education of the festival organizers and food vendors about relevant public health regulations and food safety practices, 4) traceback of the implicated product to the retailer in Indiana, and 5) notification of the Indiana State Department of Health. The results of the investigation call attention to the public health implications of unregulated food service at events such as church festivals, which generally are exempt from public health inspection and licensure in Ohio. Food sold in such environments might place populations at risk for foodborne illness.

Annual Report 1980

International Nuclear Information System (INIS)

1982-01-01

The advances in the execution of the Argentine Nuclear Program, performed by CNEA during 1980, are reported. The information is grouped in six sections: Nuclear Power Plants, Supplies to Nuclear Power Plants, Radioisotopes and Radiations, Research and Development, Radiological Protection and Nuclear Safety, and Infrastructure and General Aspects. (M.E.L.) [es

Well-spread sequences and edge-labellings with constant Hamilton-weight

Directory of Open Access Journals (Sweden)

P. Mark Kayll

2004-12-01

Full Text Available A sequence (a i of integers is well-spread if the sums a i +a j, for iHamilton cycle has the same length; we prove that 2n 2-O(n 3/2<Λ(n<2n 2 +O(n 61/40.

Trends and geographic inequalities in the prevalence of Down syndrome in Europe, 1980-1999.

Science.gov (United States)

Dolk, H; Loane, M; Garne, E; De Walle, H; Queisser-Luft, A; De Vigan, C; Addor, M C; Gener, B; Haeusler, M; Jordan, H; Tucker, D; Stoll, C; Feijoo, M; Lillis, D; Bianchi, F

2005-11-01

EUROCAT is a network of population-based registries for the epidemiologic surveillance of congenital anomalies covering approximately one quarter of births in the European Union. Down syndrome constitutes approximately 8% of cases of registered congenital anomaly in Europe, with over 7000 affected pregnancies in the 15 current member states of the European Union each year. In this paper, we aim to examine trends in the live birth prevalence of Down syndrome in Europe in the light of trends in maternal age and in prenatal diagnosis. Descriptive analysis of data from 24 EUROCAT registries, covering 8.3 million births 1980-99. Cases include live births, stillbirths and terminations of pregnancy following prenatal diagnosis. Since 1980, the proportion of births to mothers of 35 years of age and over has risen quite dramatically from 8 to 14% for the European Union as a whole, with steeper rises in some regions. By 1995-1999, the proportion of "older" mothers varied between regions from 10% to 25%, and the total prevalence (including terminations of pregnancy) of Down syndrome varied from 1 to 3 per 1000 births. Some European regions have shown a more than twofold increase in total prevalence of Down syndrome since 1980. The proportion of cases of Down syndrome which were prenatally diagnosed followed by termination of pregnancy in 1995-1999 varied from 0% in the three regions of Ireland and Malta where termination of pregnancy is illegal, to less than 50% in 14 further regions, to 77% in Paris. The extent to which terminations of pregnancy were concen trated among older mothers varied between regions. The live birth prevalence has since 1980 increasingly diverged from the rising total prevalence, in some areas remaining approximately stable, in others decreasing over time. The rise in average maternal age in Europe has brought with it an increase in the number of pregnancies affected by Down syndrome. The widespread practice of prenatal screening and termination of

Titan's fluvial valleys: Morphology, distribution, and spectral properties

Science.gov (United States)

Langhans, M.H.; Jaumann, R.; Stephan, K.; Brown, R.H.; Buratti, B.J.; Clark, R.N.; Baines, K.H.; Nicholson, P.D.; Lorenz, R.D.; Soderblom, L.A.; Soderblom, J.M.; Sotin, Christophe; Barnes, J.W.; Nelson, R.

2012-01-01

Titan's fluvial channels have been investigated based on data obtained by the Synthetic Aperture Radar (SAR) instrument and the Visible and Infrared Mapping Spectrometer (VIMS) onboard the Cassini spacecraft. In this paper, a database of fluvial features is created based on radar-SAR data aiming to unveil the distribution and the morphologic and spectral characteristics of valleys on Titan on a global scale. It will also study the spatial relations between fluvial valleys and Titan's geologic units and spectral surface units which have become accessible thanks to Cassini-VIMS data. Several distinct morphologic types of fluvial valleys can be discerned by SAR-images. Dendritic valley networks appear to have much in common with terrestrial dendritic systems owing to a hierarchical and tree-shaped arrangement of the tributaries which is indicative of an origin from precipitation. Dry valleys constitute another class of valleys resembling terrestrial wadis, an indication of episodic and strong flow events. Other valley types, such as putative canyons, cannot be correlated with rainfall based on their morphology alone, since it cannot be ruled out that they may have originated from volcanic/tectonic action or groundwater sapping. Highly developed and complex fluvial networks with channel lengths of up to 1200 km and widths of up to 10 km are concentrated only at a few locations whereas single valleys are scattered over all latitudes. Fluvial valleys are frequently found in mountainous areas. Some terrains, such as equatorial dune fields and undifferentiated plains at mid-latitudes, are almost entirely free of valleys. Spectrally, fluvial terrains are often characterized by a high reflectance in each of Titan's atmospheric windows, as most of them are located on Titan's bright 'continents'. Nevertheless, valleys are spatially associated with a surface unit appearing blue due to its higher reflection at 1.3??m in a VIMS false color RGB composite with R: 1.59/1.27??m, G: 2

Energy Balance of the Santa Catarina State - Series 1980 -1996

International Nuclear Information System (INIS)

1997-01-01

This energy balance of the Santa Catarina State presents the following main topics that can be outstanding: economic aspects; supply and demand of energy by source 1980-1996; energy consumption by sector 1980/1996; energy interchange; and balance of the transformation centers 1980/1996

Groundwater quality in Coachella Valley, California

Science.gov (United States)

Dawson, Barbara J. Milby; Belitz, Kenneth

2012-01-01

Groundwater provides more than 40 percent of California’s drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project of the GAMA Program provides a comprehensive assessment of the State’s groundwater quality and increases public access to groundwater-quality information. Coachella Valley is one of the study areas being evaluated. The Coachella study area is approximately 820 square miles (2,124 square kilometers) and includes the Coachella Valley groundwater basin (California Department of Water Resources, 2003). Coachella Valley has an arid climate, with average annual rainfall of about 6 inches (15 centimeters). The runoff from the surrounding mountains drains to rivers that flow east and south out of the study area to the Salton Sea. Land use in the study area is approximately 67 percent (%) natural, 21% agricultural, and 12% urban. The primary natural land cover is shrubland. The largest urban areas are the cities of Indio and Palm Springs (2010 populations of 76,000 and 44,000, respectively). Groundwater in this basin is used for public and domestic water supply and for irrigation. The main water-bearing units are gravel, sand, silt, and clay derived from surrounding mountains. The primary aquifers in Coachella Valley are defined as those parts of the aquifers corresponding to the perforated intervals of wells listed in the California Department of Public Health database. Public-supply wells in Coachella Valley are completed to depths between 490 and 900 feet (149 to 274 meters), consist of solid casing from the land surface to a depth of 260 to 510 feet (79 to 155 meters), and are screened or perforated below the solid casing. Recharge to the groundwater system is primarily runoff from the surrounding mountains, and by direct infiltration of irrigation. The primary sources of discharge are pumping wells, evapotranspiration, and underflow to

Homogeneous SLOWPOKE reactors for Mo-99/Tc-99m production in North America

Energy Technology Data Exchange (ETDEWEB)

Hilborn, J.W., E-mail: hilbovanw@sympatico.ca [Deep River, Ontario (Canada); Bonin, H.W. [Royal Military College of Canada, Kingston, Ontario (Canada)

2014-07-01

The 15 month shutdown of NRU in 2009 - 2010 caused an overall isotope shortage of approximately 30%; and in North America, the annual Tc-99m demand decreased from an estimated 20 million unit doses to about 15 million unit doses. Mo-99/Tc-99m is produced from HEU targets, irradiated in NRU for 11 days, and after chemical removal of uranium it is shipped to Nordion in Kanata, Ontario. Nordion further purifies the material and sends it to Lantheus Medical Imaging in the USA for manufacture of Mo-99 generators, which are then distributed to hundreds of hospital radiopharmacies throughout North America. One other American company, Covidien, manufactures and distributes Mo-99 generators like Lantheus, but they import bulk Mo-99 from Europe or South Africa. At the hospitals, Tc-99m is chemically extracted daily from the Mo-99 generators and loaded into syringes for immediate clinical use. Fortuitously, the 66 hour half-life of Mo-99 allows the replenishment of Tc-99m in the generator over a growth period of about 20 hours; and a generator can be 'milked' daily for up to two weeks. A more efficient model is the direct production and distribution of Tc-99m unit doses to regional hospitals from 10 'industrial' radiopharmacies located at existing licensed reactor sites in North America. A 20 kW homogeneous SLOWPOKE reactor at each site would deliver 15 litres of irradiated uranyl sulphate fuel solution daily to industrial-scale hot cells for extraction of Mo-99, which would be incorporated in large Mo-99/Tc-99m generators for extraction of Tc-99m five days a week; and the Low Enriched Uranium (LEU) would be recycled. Each automated hot-cell facility would be designed to load up to 7,000 Tc-99m syringes daily, for courier delivery to all of the Nuclear Medicine hospitals within a 3 hour average range by road transport. Typically, the delivered doses would be in the range 10 to 30 mCi. Assuming an average unit dose of 25 mCi at the hospital and 5 x 52

Vivid valleys, pallid peaks? Hypsometric variations and rural–urban land change in the Central Peruvian Andes

Science.gov (United States)

Haller, Andreas

2012-01-01

What happens to the land cover within the hinterland's altitudinal belts while Central Andean cities are undergoing globalization and urban restructuring? What conclusions can be drawn about changes in human land use? By incorporating a regional altitudinal zonation model, direct field observations and GIS analyses of remotely sensed long term data, the present study examines these questions using the example of Huancayo Metropolitano – an emerging Peruvian mountain city of 420,000 inhabitants, situated at 3260 m asl in the Mantaro Valley. The study's results indicate that rapid urban growth during the late 1980s and early 1990s was followed by the agricultural intensification and peri-urban condominization at the valley floor (quechua) – since the beginning of Peru's neoliberal era. Moreover, regarding the adjoining steep slopes (suni) and subsequent grassland ecosystems (puna), the research output presents land cover change trajectories that clearly show an expansion of human land use, such as reforestation for wood production and range burning for livestock grazing, even at high altitudes – despite rural–urban migration trends and contrary to several results of extra-Andean studies. Consequently, rural–urban planners and policy makers are challenged to focus on the manifold impacts of globalization on human land use – at all altitudinal belts of the Andean city's hinterland: toward sustainable mountain development that bridges the social and physical gaps – from the bottom up. PMID:23564987

99Mo production for using in the nuclear medicine in 99mTc generators

International Nuclear Information System (INIS)

Kurenkov, N.V.; Chuvilin, D.Yu.

1999-01-01

The review of methods and advanced technologies for obtaining 99 Mo in nuclear reactors is presented. The 99 Mo isotope is used for preparing the 99m Tc generators, widely applied in nuclear medicine. The reactor method for obtaining 99 Mo is based on the 98 Mo(n, γ) 99 Mo radiation capture reaction and 235 U fission reaction under the effect of the 235 U (n, f) 99 Mo reaction. The results of studies on obtaining 99 Mo on the charged particles accelerators, mainly, on the proton beam and under the effect of photonuclear reaction is also described. The data on the 99 Mo real consumption and forecast for its application in different regions of the world from 1994 up to 2006 are presented [ru

Development of 99mTc extraction techniques from 99Mo by (n,γ) reaction

International Nuclear Information System (INIS)

Kimura, Akihiro; Hori, Naohiko; Tsuchiya, Kunihiko; Ishihara, Masahiro; Yamabayashi, Hisamichi; Tanase, Masakazu; Fujisaki, Saburo; Sato, Yuichi

2010-11-01

Investigation of production method of 99 Mo by (n, γ) reaction, where the processing is relatively simple and generating less amount of radioactive waste, is conducted in the Neutron Irradiation and Testing Reactor Center. The 99 Mo is adsorbed to highly efficient adsorbent PZC after neutron irradiation and 99m Tc is eluted. However, radioactivity concentration of the 99m Tc solution obtained from PZC column loaded with 99 Mo derived by (n, γ) method is lower than that obtained from alumina column with 99 Mo by (n, f) method due to extremely low specific activity of (n, f) 99 Mo. Therefore, it is necessary to develop technique for increasing the amount of 99 Mo and the 99m Tc solution of high radioactivity concentration (minimum: 1Ci/ cm 3 ). In this study, the preliminary fabrication tests using high density MoO 3 pellets were carried out to increase the production of 99 Mo. The method of concentrating 99m Tc solution through solvent extraction with MEK was investigated and a device for this concentration process was also developed. In the preliminary tests of the MoO 3 pellets, the pellets having high density were successfully fabricated by the SPS method. Additionally, it was ascertained that the pellets can be dissolved with 6M-NaOH solution completely. The test for 99 Mo adsorption followed by 99m Tc elution using PZC was carried out. As the result, amount of Mo adsorbed to 1g-PZC was about 250mg, and 99m Tc yield was about 80%. In the concentration test using Re solution instead of 99m Tc solution, it was ascertained that the concentration efficiency is higher than 80% of the theoretical value. A concentration device for 99m Tc solution could be realized based on the method employed in the present experiments. The outcomes of development of 99m Tc extraction techniques from 99 Mo by (n,γ) reaction was reviewed in this paper, and the contents were presented in the 3rd International Symposium on Material Test Reactors. (author)

14 CFR 99.1 - Applicability.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Applicability. 99.1 Section 99.1... AND GENERAL OPERATING RULES SECURITY CONTROL OF AIR TRAFFIC General § 99.1 Applicability. (a) This... Identification Zone (ADIZ) designated in subpart B. (b) Except for §§ 99.7, 99.13, and 99.15 this subpart does...

Twenty-fourth annual report 1980

International Nuclear Information System (INIS)

1981-01-01

In this report progress for 1980 is reported on the following: nuclear materials; nuclear power; application of radioisotopes and radiation; health and safety; fundamental studies undertaken in the fields of nuclear physics, plasma physics, theoretical physics, radiation chemistry, research on liquid metals and molten salts, solid-state physics and the medical and biological sciences. The supporting activities of the research reactor, electronic engineering, waste treatment and disposal, analytical services, engineering services and computing services are discussed. The activities of the external relations division and licensing division are also discussed. The report contains a bibliography of publications published by staff members and bursars of the Atomic Energy Board during 1980

Use of 99mTc from a commercial 99Mo/9mTc generator as yield tracer for the determination of 99Tc at low levels

DEFF Research Database (Denmark)

Hou, Xiaolin; Jensen, Mikael; Nielsen, Sven Poul

2007-01-01

The concentrations of Tc-99 and impurity radionuclides in the Tc-99m tracer solution obtained from a commercial Mo-99/Tc-99m generator were measured by gamma spectrometry and liquid scintillation counting. Mo-99 and Ru-103 were found in the Tc-99m eluate. A simple separation using two extra alumina...... cartridges was investigated to purify the eluate to obtain a suitable Tc-99m tracer with low Tc-99 concentration. The activity ratio of Tc-99/Tc-99m in the prepared Tc-99m solution is lower than 15 x 10(-9), which is higher than the theoretical ratio of less than 10 x 10(-9). The possible reason is discussed....... The Tc-99 in the 20 kBq spiked Tc-99m tracer was found to be less than 0.3mBq, which is lower than the detection limit of the radiometric method used for environmental samples. The purified Tc-99m eluate is used as yield tracer for the determination of low levels of Tc-99 in environmental samples. (c...

Preparation of a gel of zirconium molybdate for use in the generators of 99 Mo - 99m Tc prepared with 99 Mo produced by the 98 Mo(n,γ)99 Mo reaction

International Nuclear Information System (INIS)

Osso Junior, Joao A.; Lima, Ana Lucia V.P.; Silva, Nestor C. da; Nieto, Renata C.; Velosa, Adriana C. de

1998-01-01

IPEN develops a project concerning the preparation of a gel of Zirconium Molybdate for use in the generators of 99 Mo- 99m Tc . 99m Tc is the most used radioisotope in nuclear medicine diagnosis procedures and nowadays the generators are being prepared with imported 99 Mo, produced by 235 U fission. The production of 99 Mo by the 98 Mo(n, γ) 99 Mo reaction is now possible because of the power upgrade of IPEN's IEA-R1 reactor, from 2 to 5 MW. This work describes the preparation method of Zirconium Molybdate gel that will be used in the 99 Mo- 99m Tc generators. The gel is prepared by the chemical reaction between Mo, in Mo O 3 form, and Zr, in Zr O Cl 2 .8H 2 O form. After the reaction, the gel is filtered, dried and cracked with saline solution. The product is then loaded into glass columns for use as 99m Tc generator. The results showed the good quality of the gel prepared at laboratory level and of the generators evaluated. (author)

Historic Settlement in the Upper Tombigbee Valley.

Science.gov (United States)

1981-02-28

Building Characteristics in Southern Virginia." Ph.D. dissertation, Rutgers University, 1968. Hamilton, Charles G. " Lyric Monroe: A County Anthology...in the American Old West." In . reen. ed .. Essays in Scotch-Irish Historv. London: RoutIedze and Ve, in Piul. 1)h9. Evans, W.A. "Gaines Trace in...555-70. Weaver, David C. ed. Essays on the Human Geography of the Southeastern States. In West Georgia Studies in the Social Sciences. Vol. 16 (1977

DDT poisoning of big brown bats, Eptesicus fuscus, in Hamilton, Montana.

Science.gov (United States)

Buchweitz, John P; Carson, Keri; Rebolloso, Sarah; Lehner, Andreas

2018-06-01

Dichlorodiphenyltrichloroethane (DDT) is an insecticidal organochlorine pesticide with; known potential for neurotoxic effects in wildlife. The United States Environmental Protection Agency (US EPA) registration for this pesticide has been cancelled and there are currently no federally active products that contain this ingredient in the U.S. We present a case of a colony of big brown bats (E. Fuscus) found dead in the attic roost of an administrative building; in the city of Hamilton, Montana from unknown cause. DDT and its metabolites; dichlorodiphenyldichloroethylene (DDE) and dichlorodiphenyldichloroethane (DDD) were detected in bat tissues by gas chromatography/mass spectrometry (GC-MS) and quantified by gas chromatography tandem quadrupole mass spectrometry (GC-MS/MS). Concentrations of 4081 ppm DDT and 890 ppm DDE wet weight were found in the brain of one bat and are the highest reported concentrations in such a mortality event to date. This case emphasizes the importance of testing wildlife mortalities against a comprehensive panel of toxicologic agents including persistent organic pollutants in the absence of other more common disease threats. Copyright © 2018 Elsevier Ltd. All rights reserved.

Preparation of i.v. 99mTc radiopharmaceuticals from spent moly 99Mo

International Nuclear Information System (INIS)

Noronha, O.P.D.

1998-01-01

Full text: Expiry dating is an important quality assurance precept in (radio) pharmacy. There are occasions when for the sake of patient service one may be forced to continue using an over aged source of 99 Mo to generate 99m Tc beyond 7d, especially when there is short/no supply of 99 Mo, (In the early days the expiry date was 3 d or 3 extractions, whichever one was earlier). With the passage of time a few physico-chemical changes (apart from decay) do occur in the 99 Mo/ 99m Tc milieu. The cocktail also begins to contain traces of carried over MEK which is subjected to strong β-, γ irradiation. These impurity (in trace amounts) is soluble in MEK and even, to an extent, in aqueous media. Furthermore, the concentrated impurity tends to seemingly increase in the bulk 99m TcO 4 - since one is compelled to leach TcO 4 - in lower volume of saline. On many occasions we have been constrained to extend the use of 99 Mo beyond 7 - 14 d. Adequate activities were obtained by pooling the previous week's lot of 99 Mo with the current over aged lot. On a few occasions over the past 26 years we have used 99 Mo much beyond 14 d and 2 - 3 occasions for 26 - 28 d (i.e. >10 t 1 /2 of 99 Mo). On each of these occasions the purity of 99m TcO- 4 was ascertained by pharmacopoeial procedures. It was found that despite depleting activities, the purity was not compromised and the trace impurities, even if present, did not cause any interference. We have profitably utilised the bulk TcO- 4 to formulate a variety of i.v. dosage forms of 99m Tc radiodiagnostics. The following strategy was adopted for the patient services - the agents requiring larger activity levels/patients dose were made available in the earlier period, the other during the latter half. It is concluded that pure 99m TcO- 4 can be obtained over the entire useful life-period of 99 Mo, even > 10t l/2

EPA Region 1 - Map Layers for Valley ID Tool (Hosted Feature Service)

Science.gov (United States)

The Valley Service Feature Layer hosts spatial data for EPA Region 1's Valley Identification Tool. These layers contain attribute information added by EPA R1 GIS Center to help identify populated valleys:- Fac_2011NEI: Pollution sources selected from the National Emissions Inventory (EPA, 2011).- NE_Towns_PopValleys: New England Town polygons (courtesy USGS), with Population in Valleys and Population Density in Valleys calculated by EPA R1 GIS, from 2010 US Census blocks. - VT_E911: Vermont residences (courtesy VT Center for Geographic Information E-911).

Valley photonic crystals for control of spin and topology

Energy Technology Data Exchange (ETDEWEB)

Dong, Jian-Wen; Chen, Xiao-Dong; Zhu, Hanyu; Wang, Yuan; Zhang, Xiang

2016-11-28

Photonic crystals offer unprecedented opportunity for light manipulation and applications in optical communication and sensing1,2,3,4. Exploration of topology in photonic crystals and metamaterials with non-zero gauge field has inspired a number of intriguing optical phenomena such as one-way transport and Weyl points5,6,7,8,9,10. Recently, a new degree of freedom, valley, has been demonstrated in two-dimensional materials11,12,13,14,15. Here, we propose a concept of valley photonic crystals with electromagnetic duality symmetry but broken inversion symmetry. We observe photonic valley Hall effect originating from valley-dependent spin-split bulk bands, even in topologically trivial photonic crystals. Valley–spin locking behaviour results in selective net spin flow inside bulk valley photonic crystals. We also show the independent control of valley and topology in a single system that has been long pursued in electronic systems, resulting in topologically-protected flat edge states. Valley photonic crystals not only offer a route towards the observation of non-trivial states, but also open the way for device applications in integrated photonics and information processing using spin-dependent transportation.

A comparative study of 99Tcm-tetrofosmin and 99Tcm-MIBI myocardial imaging

International Nuclear Information System (INIS)

Zhao Kui; Chen Peng; Zhang Furong; Shen Wenhua

2001-01-01

Objective: To evaluate the value of 99 Tc m -tetrofosmin myocardial imaging for detecting coronary artery disease. Methods: Twenty-seven patients underwent 99 Tc m -tetrofosmin SPECT, twenty-six patients underwent 99 Tc m -MIBI SPECT; coronary angiography was performed on patients included in both groups (≥50% luminal diameter stenosis was considered significant coronary stenosis). Results: 99 Tc m -tetrofosmin produced high quality myocardial images from 30 min to several hours postinjection, the outlines of myocardial perfusion images provided by 99 Tc m -tetrofosmin imaging were clearly discernible. One-day exercise/rest 99 Tc m -tetrofosmin myocardial perfusion imaging was feasible and had a high sensitivity for detection of coronary artery disease. Sensitivities of 99 Tc m -tetrofosmin SPECT and 99 Tc m -MIBI SPECT for detecting coronary artery disease were 90% and 94%, respectively. The 95% confidence limits of both sensitivities were 68.65% - 98.77% and 72.33% - 99.86%, respectively; the positive predictive values of both imaging agents were 90.0% and 89.5%, respectively, the 95% confidence limits of those were 68.38% - 98.77% and 72.33% - 99.86% respectively; the positive predictive values of both imaging agents were 90.0% and 89.5%, respectively, the 95% confidence limits of those were 68.38% - 98.77% and 66.38% - 98.70%, respectively; efficiencies of both imaging agents were 85.2% and 88.5%, respectively. The 95% confidence limits of both efficiencies were 65.81% - 95.78% and 69.44 - 98.70%, respectively. The specificity for both imaging agents was 71% and 75%. There was no significant difference among above results (P > 0.05). No ECG abnormalities were found following the injection of 99 Tc m -tetrofosmin SPECT. There were no drug-related effects on blood pressure, heart rate and body temperature. This experiment failed to provide the negative predictive value of the myocardial perfusion imaging with 99 Tc m -tetrofosmin because that few patients with

Precipitation and runoff simulations of select perennial and ephemeral watersheds in the middle Carson River basin, Eagle, Dayton, and Churchill Valleys, west-central Nevada

Science.gov (United States)

Jeton, Anne E.; Maurer, Douglas K.

2011-01-01

The effect that land use may have on streamflow in the Carson River, and ultimately its impact on downstream users can be evaluated by simulating precipitation-runoff processes and estimating groundwater inflow in the middle Carson River in west-central Nevada. To address these concerns, the U.S. Geological Survey, in cooperation with the Bureau of Reclamation, began a study in 2008 to evaluate groundwater flow in the Carson River basin extending from Eagle Valley to Churchill Valley, called the middle Carson River basin in this report. This report documents the development and calibration of 12 watershed models and presents model results and the estimated mean annual water budgets for the modeled watersheds. This part of the larger middle Carson River study will provide estimates of runoff tributary to the Carson River and the potential for groundwater inflow (defined here as that component of recharge derived from percolation of excess water from the soil zone to the groundwater reservoir). The model used for the study was the U.S. Geological Survey's Precipitation-Runoff Modeling System, a physically based, distributed-parameter model designed to simulate precipitation and snowmelt runoff as well as snowpack accumulation and snowmelt processes. Models were developed for 2 perennial watersheds in Eagle Valley having gaged daily mean runoff, Ash Canyon Creek and Clear Creek, and for 10 ephemeral watersheds in the Dayton Valley and Churchill Valley hydrologic areas. Model calibration was constrained by daily mean runoff for the 2 perennial watersheds and for the 10 ephemeral watersheds by limited indirect runoff estimates and by mean annual runoff estimates derived from empirical methods. The models were further constrained by limited climate data adjusted for altitude differences using annual precipitation volumes estimated in a previous study. The calibration periods were water years 1980-2007 for Ash Canyon Creek, and water years 1991-2007 for Clear Creek. To

{sup 99m}Tc-MDP scintigraphy of femoral head necrosis following femoral neck fracture

Energy Technology Data Exchange (ETDEWEB)

Lee, Soon Jin; Lee, Jun Hyung; Kim, Eun Kyung; Lee, Sun Wha; Kim, Soon Yong [Kyung Hee University School of Medicine, Seoul (Korea, Republic of)

1985-02-15

Secondary ischemic necrosis of femoral head due to loss of blood supply following to femoral neck fracture is well known. The regional distribution of bone-seeking radiopharmaceuricals in the skeleton can depend on a number of factors, but bone blood flow is a major physiological determinant of regional skeletal uptake of Tc-99m polyphosphate and bone imaging may thus be used for the evaluation of vascularity of the femoral head. The authors made a comparative study of scintigraphic findings and operative findings of 28 cases of femoral neck fracture treated at Kyung Hee University Hospital from April 1980 to May 1984. The results were as follows: 1. In 16 cases of proven avascular necorsis of femoral head, scintigraphy showed absent or decreased activity in 14 cases (87.5%), while radiography showed increased density in 10 cases (62.5%). 2. In 12 cases of proven vital femoral head, scintigraphy showed increased activity in 9 cases (75%) and radiography showed decreased density in 9 cases (75%). 3. 99mTc-MDP scintigraphy was an excellent and useful method for assessing bone vitality of femoral head.

Synthesis and characterization of zirconium molybdates of 99 Mo/99m Tc generators

International Nuclear Information System (INIS)

Contreras R, A.; Monroy G, F.; Diaz A, L.V.

2002-01-01

The zirconium molybdates are gels which are used as cation exchangers in the production of 99 Mo/ 99m Tc generators. The synthesis method and the characterization of these gels by thermogravimetry, infrared spectroscopy and X-ray diffraction is presented with the purpose of finding which the factors are that influence in the efficiency of the 99m Tc production. The results show that the quantity of molecular water contained in gel, is possibly the cause of variations of the efficiencies of the 99 Mo/ 99m Tc generator. (Author)

Breathing Valley Fever

Centers for Disease Control (CDC) Podcasts

2014-02-04

Dr. Duc Vugia, chief of the Infectious Diseases Branch in the California Department of Public Health, discusses Valley Fever.  Created: 2/4/2014 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 2/5/2014.

Solutions to estimation problems for scalar hamilton-jacobi equations using linear programming

KAUST Repository

Claudel, Christian G.; Chamoin, Timothee; Bayen, Alexandre M.

2014-01-01

This brief presents new convex formulations for solving estimation problems in systems modeled by scalar Hamilton-Jacobi (HJ) equations. Using a semi-analytic formula, we show that the constraints resulting from a HJ equation are convex, and can be written as a set of linear inequalities. We use this fact to pose various (and seemingly unrelated) estimation problems related to traffic flow-engineering as a set of linear programs. In particular, we solve data assimilation and data reconciliation problems for estimating the state of a system when the model and measurement constraints are incompatible. We also solve traffic estimation problems, such as travel time estimation or density estimation. For all these problems, a numerical implementation is performed using experimental data from the Mobile Century experiment. In the context of reproducible research, the code and data used to compute the results presented in this brief have been posted online and are accessible to regenerate the results. © 2013 IEEE.

Groundwater-flow and land-subsidence model of Antelope Valley, California

Science.gov (United States)

Siade, Adam J.; Nishikawa, Tracy; Rewis, Diane L.; Martin, Peter; Phillips, Steven P.

2014-01-01

Antelope Valley, California, is a topographically closed basin in the western part of the Mojave Desert, about 50 miles northeast of Los Angeles. The Antelope Valley groundwater basin is about 940 square miles and is separated from the northern part of Antelope Valley by faults and low-lying hills. Prior to 1972, groundwater provided more than 90 percent of the total water supply in the valley; since 1972, it has provided between 50 and 90 percent. Most groundwater pumping in the valley occurs in the Antelope Valley groundwater basin, which includes the rapidly growing cities of Lancaster and Palmdale. Groundwater-level declines of more than 270 feet in some parts of the groundwater basin have resulted in an increase in pumping lifts, reduced well efficiency, and land subsidence of more than 6 feet in some areas. Future urban growth and limits on the supply of imported water may increase reliance on groundwater.

Enhanced valley splitting in monolayer WSe2 due to magnetic exchange field.

Science.gov (United States)

Zhao, Chuan; Norden, Tenzin; Zhang, Peiyao; Zhao, Puqin; Cheng, Yingchun; Sun, Fan; Parry, James P; Taheri, Payam; Wang, Jieqiong; Yang, Yihang; Scrace, Thomas; Kang, Kaifei; Yang, Sen; Miao, Guo-Xing; Sabirianov, Renat; Kioseoglou, George; Huang, Wei; Petrou, Athos; Zeng, Hao

2017-08-01

Exploiting the valley degree of freedom to store and manipulate information provides a novel paradigm for future electronics. A monolayer transition-metal dichalcogenide (TMDC) with a broken inversion symmetry possesses two degenerate yet inequivalent valleys, which offers unique opportunities for valley control through the helicity of light. Lifting the valley degeneracy by Zeeman splitting has been demonstrated recently, which may enable valley control by a magnetic field. However, the realized valley splitting is modest (∼0.2 meV T -1 ). Here we show greatly enhanced valley spitting in monolayer WSe 2 , utilizing the interfacial magnetic exchange field (MEF) from a ferromagnetic EuS substrate. A valley splitting of 2.5 meV is demonstrated at 1 T by magnetoreflectance measurements and corresponds to an effective exchange field of ∼12 T. Moreover, the splitting follows the magnetization of EuS, a hallmark of the MEF. Utilizing the MEF of a magnetic insulator can induce magnetic order and valley and spin polarization in TMDCs, which may enable valleytronic and quantum-computing applications.

Quaternary glaciation of the Tashkurgan Valley, Southeast Pamir

Science.gov (United States)

Owen, Lewis A.; Chen, Jie; Hedrick, Kathyrn A.; Caffee, Marc W.; Robinson, Alexander C.; Schoenbohm, Lindsay M.; Yuan, Zhaode; Li, Wenqiao; Imrecke, Daniel B.; Liu, Jinfeng

2012-07-01

The Quaternary glacial history of Tashkurgan valley, in the transition between the Pamir and Karakoram, in Xinjiang Province, China was examined using remote sensing, field mapping, geomorphic analysis of landforms and sediments, and 10Be terrestrial cosmogenic nuclide dating. Moraines were assigned to four glacial stages: 1) the Dabudaer glacial stage that dates to the penultimate glacial cycle and/or earlier, and may represent one or more glaciations; 2) the Tashkurgan glacial stage that dates to early last glacial, most likely Marine Oxygen Isotope Stage (MIS) 4; 3) the Hangdi glacial stage that dates to MIS 2, possibly early MIS 2; and 4) the Kuzigun glacial stage that dates to the MIS 2, possibly the global Last Glacial Maximum, and is younger than the Hangdi glacial stage. Younger moraines and rock glaciers are present at the heads of tributary valleys; but these were inaccessible because they are located close to politically sensitive borders with Pakistan, Afghanistan and Tajikistan. Glaciers during the Dabudaer glacial stage advanced into the central part of the Tashkurgan valley. During the Tashkurgan glacial stages, glaciers advanced several kilometers beyond the mouths of the tributary valleys into the Tashkurgan valley. Glaciers during the Hangdi and Kuzigun glacial stages advanced just beyond the mouths of the tributary valleys. Glaciation in this part of the Himalayan-Tibetan orogen is likely strongly controlled by northern hemisphere climate oscillations, although a monsoonal influence on glaciation cannot be ruled out entirely.

Synthesis and characterization of zirconium molybdates of {sup 99} Mo/{sup 99m} Tc generators; Sintesis y caracterizacion de molibdatos de zirconio de generadores {sup 99} Mo/{sup 99m} Tc

Energy Technology Data Exchange (ETDEWEB)

Contreras R, A.; Monroy G, F.; Diaz A, L.V. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

2002-07-01

The zirconium molybdates are gels which are used as cation exchangers in the production of {sup 99} Mo/{sup 99m} Tc generators. The synthesis method and the characterization of these gels by thermogravimetry, infrared spectroscopy and X-ray diffraction is presented with the purpose of finding which the factors are that influence in the efficiency of the {sup 99m} Tc production. The results show that the quantity of molecular water contained in gel, is possibly the cause of variations of the efficiencies of the {sup 99} Mo/{sup 99m} Tc generator. (Author)

Potential hydrologic characterization wells in Amargosa Valley

International Nuclear Information System (INIS)

Lyles, B.; Mihevc, T.

1994-09-01

More than 500 domestic, agricultural, and monitoring wells were identified in the Amargosa Valley. From this list, 80 wells were identified as potential hydrologic characterization wells, in support of the US Department of Energy (DOE) Underground Test Area/Remedial Investigation and Feasibility Study (UGTA/RIFS). Previous hydrogeologic studies have shown that groundwater flow in the basin is complex and that aquifers may have little lateral continuity. Wells located more than 10 km or so from the Nevada Test Site (NTS) boundary may yield data that are difficult to correlate to sources from the NTS. Also, monitoring well locations should be chosen within the guidelines of a hydrologic conceptual model and monitoring plan. Since these do not exist at this time, recompletion recommendations will be restricted to wells relatively close (approximately 20 km) to the NTS boundary. Recompletion recommendations were made for two abandoned agricultural irrigation wells near the town of Amargosa Valley (previously Lathrop Wells), for two abandoned wildcat oil wells about 10 km southwest of Amargosa Valley, and for Test Well 5 (TW-5), about 10 km east of Amargosa Valley

Evaluation of the absorbed dose to the kidneys due to Tc99m (DTPA) / Tc99m (Mag3) and Tc99m (Dmsa)

International Nuclear Information System (INIS)

Vasquez A, M.; Murillo C, F.; Castillo D, C.; Rocha J, J.; Sifuentes D, Y.; Sanchez S, P.; Idrogo C, J.; Marquez P, F.

2015-10-01

The absorbed dose in the kidneys of adult patients has been assessed using the biokinetics of radiopharmaceuticals containing Tc 99m (DTPA) / Tc 99m (Mag3) or Tc 99m (Dmsa).The absorbed dose was calculated using the formalism MIRD and the Cristy-Eckerman representation for the kidneys. The absorbed dose to the kidneys due to Tc 99m (DTPA) / Tc 99m (Mag3), are given by 0.00466 mGy.MBq -1 / 0.00339 mGy.MBq -1 . Approximately 21.2% of the absorbed dose is due to the bladder (content) and the remaining tissue, included in biokinetics of Tc 99m (DTPA) / Tc 99m (Mag3). The absorbed dose to the kidneys due to Tc 99m (Dmsa) is 0.17881 mGy.MBq -1 . Here, 1.7% of the absorbed dose is due to the bladder, spleen, liver and the remaining tissue, included in biokinetics of Tc 99m (Dmsa). (Author)

Trace Formulae of Characteristic Polynomial and Cayley-Hamilton's Theorem, and Applications to Chiral Perturbation Theory and General Relativity

International Nuclear Information System (INIS)

Zhang Honghao; Yan Wenbin; Li Xuesong

2008-01-01

By using combinatorics, we give a new proof for the recurrence relations of the characteristic polynomial coefficients, and we further obtain an explicit expression for the generic term of the coefficient sequence, which yields the trace formulae of the Cayley-Hamilton's theorem with all coefficients explicitly given. This implies a byproduct, a complete expression for the determinant of any finite-dimensional matrix in terms of the traces of its successive powers. And we discuss some of their applications to chiral perturbation theory and general relativity

MX Siting Investigation. Gravity Survey - Sevier Desert Valley, Utah.

Science.gov (United States)

1981-01-24

Cheyenne, Wyoming. DMAHTC reduces the data to Simple Bouguer Anomaly (see Section A1.4, Appendix Al.0). The Defense Mapping Agency Aerospace Center...Desert Valley, Utah ......... 2 2 Topographic Setting - Sevier Desert Valley, Utah . 3 LIST OF DRAWINGS Drawing Number 1 Complete Bouguer Anomaly...gravity stations were distributed throughout the valley at an approxi- mate interval of 1.4 miles (2.3 km). Drawing 1 is a Complete Bouguer Anomaly

Separation of sup(99m)Tc from 99Mo through a hydrous zirconium oxide column

International Nuclear Information System (INIS)

Mengatti, J.

1980-01-01

The preparation of 99 Mo-,sup(99m)Tc generator based on the adsorption of 99 Mo on hydrous zirconium oxide column, employing the in exchange technique, is described. The adsorption of 99 Mo on hydrous zirconium oxide (HZO) and the separation of sup(99m)Tc, generated by the decay of 99 Mo with saline solution, are analised. The sup(99m)Tc separation yield, pH of the eluted solution, aspect of the elution curve and the adsorption of 99 Mo on hydrous zirconium oxide calcined at 800 0 C are studied. The chemical and radioactive purities of the final product are analysed and the variation of the elution yield for successive elutions is studied. (Author) [pt

Sutter Buttes-the lone volcano in California's Great Valley

Science.gov (United States)

Hausback, Brain P.; Muffler, L.J. Patrick; Clynne, Michael A.

2011-01-01

The volcanic spires of the Sutter Buttes tower 2,000 feet above the farms and fields of California's Great Valley, just 50 miles north-northwest of Sacramento and 11 miles northwest of Yuba City. The only volcano within the valley, the Buttes consist of a central core of volcanic domes surrounded by a large apron of fragmental volcanic debris. Eruptions at the Sutter Buttes occurred in early Pleistocene time, 1.6 to 1.4 million years ago. The Sutter Buttes are not part of the Cascade Range of volcanoes to the north, but instead are related to the volcanoes in the Coast Ranges to the west in the vicinity of Clear Lake, Napa Valley, and Sonoma Valley.

Gravity and magnetic data of Midway Valley, southwest Nevada

International Nuclear Information System (INIS)

Ponce, D.A.; Langenheim, V.E.; Sikora, R.F.

1993-01-01

Detailed gravity and ground magnetic data collected along five traverses across Midway Valley on the eastern flank of Yucca Mountain in southwest Nevada are described. These data were collected as part of an effort to evaluate faulting in the vicinity of proposed surface facilities for a potential nuclear waste repository at Yucca Mountain. Geophysical data show that Midway Valley is bounded by large gravity and magnetic anomalies associated with the Bow Ridge and Paintbrush Canyon faults, on the west side of Exile Hill and on the west flank of Fran Ridge, respectively. In addition, Midway Valley itself is characterized by a number of small-amplitude anomalies that probably reflect small-scale faulting beneath Midway Valley

Annual report, 1980

International Nuclear Information System (INIS)

1980-12-01

This report covers the period between Nov. 1, 1979 and Nov. 1, 1980. Work was carried out in the fields of pure and applied nuclear physics, atomic physics, and radiobiology. Thirty-four projects belonging to Laval researchers and twelve run by external users are under way. Thirty research subjects pursued during the year are described, and a list of publications is included

27 CFR 9.208 - Snake River Valley.

Science.gov (United States)

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Snake River Valley. 9.208... Snake River Valley. (a) Name. The name of the viticultural area described in this section is “Snake River Valley”. For purposes of part 4 of this chapter, “Snake River Valley” is a term of viticultural...

Subglacial tunnel valleys in the Alpine foreland: an example from Bern, Switzerland

International Nuclear Information System (INIS)

Duerst Stucki, M.; Reber, R.; Schlunegger, F.

2010-01-01

The morphology of the Alpine and adjacent landscapes is directly related to glacial erosion and associated sediment transport. Here we report the effects of glacio-hydrologic erosion on bedrock topography in the Swiss Plateau. Specifically, we identify the presence of subsurface valleys beneath the city of Bern and discuss their genesis. Stratigraphic investigations of more than 4'000 borehole data within a 430 km 2 -large area reveal the presence of a network of >200 m-deep and 1'000 m-wide valleys. They are flat floored with steep sided walls and are filled by Quaternary glacial deposits. The central valley beneath Bern is straight and oriented towards the NNW, with valley flanks more than 20 o steep. The valley bottom has an irregular undulating profile along the thalweg, with differences between sills and hollows higher than 50-100 m over a reach of 4 km length. Approximately 500 m high bedrock highlands flank the valley network. The highlands are dissected by up to 80 m-deep and 500 m-broad hanging valleys that currently drain away from the axis of the main valley. We interpret the valleys beneath the city of Bern to be a tunnel valley network which originated from subglacial erosion by melt water. The highland valleys served as proglacial meltwater paths and are hanging with respect to the trunk system, indicating that these incipient highland systems as well as the main gorge beneath Bern formed by glacial melt water under pressure. (authors)

Gate-tunable valley-spin filtering in silicene with magnetic barrier

Energy Technology Data Exchange (ETDEWEB)

Wu, X. Q., E-mail: xianqiangzhe@126.com [National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing 210093 (China); Meng, H. [School of Physics and Telecommunication Engineering, Shanxi University of Technology, Hanzhong 723001 (China)

2015-05-28

We theoretically study the valley- and spin-resolved scattering through magnetic barrier in a one layer thick silicene, using the mode-matching method for the Dirac equation. We show that the spin-valley filtering effect can be achieved and can also be tuned completely through both a top and bottom gate. Moreover, when reversing the sign of the staggered potential, we find the direction of the valley polarization is switched while the direction of spin polarization is unchanged. These results can provide some meaningful information to design valley valve residing on silicene.

Studies of techniques for the post-elution concentration of 99mTc obtained from gel type 99Mo/99mTc generators

International Nuclear Information System (INIS)

Suzuki, Katia Noriko

2009-01-01

On average 80% of the radiopharmaceuticals used in Nuclear Medicine are labeled with 99 mTc due to its physical properties and easy attainment through of 99 Mo/ 99 mTc generators. The Directory of Radiopharmacy (DIRF) of IPEN-CNEN/SP developed a gel type chromatographic generator of MoZr with 99 Mo produced by 98 Mo(n,γ) 99 Mo reaction that occurs at the IEA-R1 Nuclear Reactor. The gel is composed of zirconium molybdate with elution volume of 12 mL with an activity of 11100 MBq (300 mCi) producing a radioactive concentration of 925 MBq (25 mCi)/mL. The fission generator gives a higher radioactive concentration around 1850 MBq (50 mCi)/mL. The aim of this work is to study a system of post-elution concentration of 99 mTc for the attainment of a high enough radioactive concentration to meet the demands of the market, with a proved quality. Two types of systems of post-elution concentration were developed: the single and the tandem. The most appropriate system for the gel generator of 99 Mo/ 99 mTc, being at the same time sterile and vacuum automated, was the tandem system using Dionex 2.5 cc/QMA cartridges. The gel generator is eluted with 10 mL of solution of 0.1% NaCl and the pertechnetate anion is retained in the QMA cartridge and further eluted with 4 mL of saline. The process takes no more than 30 minutes. The elution efficiency of the system of concentration was 90 %. At the beginning of 2009 a global crisis in the supply of 99 Mo took place making it necessary the development of alternative technologies for the production of 99 Mo/ 99 mTc generators using fission produced 99 Mo and the development of an appropriate method to extend the useful life of this generator. The results of this study showed that the same system developed for the post- concentration of the gel generator can be employed for the fission generator, using the tandem system, giving a concentration factor of 3 for the elution of 99 mTc. (author)

National Energy Balance - 1980

International Nuclear Information System (INIS)

Anon.

1980-01-01

The energy fluxes of several primary and secondary energy sources, since the production to the final consumption in the main economic sectors, are presented. The forecasting of uranium concentrate consumption and production is made for six years - 1980 to 1985. (E.G.) [pt

Michigan forest statistics, 1980.

Science.gov (United States)

Gerhard K. Raile; W. Brad Smith

1983-01-01

The fourth inventory of the timber resource of Michigan shows a 7% decline in commercial forest area and a 27% gain in growing-stock volume between 1966 and 1980. Highlights and statistics are presented on area, volume, growth, mortality, removals, utilization, and biomass.

The preparation of {sup 99m}Tc from {sup 99}Mo-{sup 99m}Tc using Poly-Zirconium Compound (PZC)

Energy Technology Data Exchange (ETDEWEB)

Laohawilai, S [Isotope Production Div., Office of Atomic Energy for Peace (Thailand)

1998-10-01

The process of for providing the {sup 99m}Tc-gel generator followed the protocol that received from Department of Radioisotopes, Tokai Research Establishment, JAERI. Sodium molybdate (molybdenum-99), pH 7 with concentration 20 mg/ml and activity nearly 1 mCi/ml was added into the adsorbent (PZC). The total activity of {sup 99}Mo was about 10 mCi and the heating time was varied from 3-18 hours at 70degC. The properties of the gel were studied for elution profile and elution efficiency. The molybdenum breakthrough in sodium pertechnetate (technetium-99m) was also performed. (author)

VALDRIFT 1.0: A valley atmospheric dispersion model with deposition

Energy Technology Data Exchange (ETDEWEB)

Allwine, K.J.; Bian, X.; Whiteman, C.D.

1995-05-01

VALDRIFT version 1.0 is an atmospheric transport and diffusion model for use in well-defined mountain valleys. It is designed to determine the extent of ddft from aedal pesticide spraying activities, but can also be applied to estimate the transport and diffusion of various air pollutants in valleys. The model is phenomenological -- that is, the dominant meteorological processes goveming the behavior of the valley atmosphere are formulated explicitly in the model, albeit in a highly parameterized fashion. The key meteorological processes treated are: (1) nonsteady and nonhomogeneous along-valley winds and turbulent diffusivities, (2) convective boundary layer growth, (3) inversion descent, (4) noctumal temperature inversion breakup, and (5) subsidence. The model is applicable under relatively cloud-free, undisturbed synoptic conditions and is configured to operate through one diumal cycle for a single valley. The inputs required are the valley topographical characteristics, pesticide release rate as a function of time and space, along-valley wind speed as a function of time and space, temperature inversion characteristics at sunrise, and sensible heat flux as a function of time following sunrise. Default values are provided for certain inputs in the absence of detailed observations. The outputs are three-dimensional air concentration and ground-level deposition fields as a function of time.

Valley-selective optical Stark effect probed by Kerr rotation

Science.gov (United States)

LaMountain, Trevor; Bergeron, Hadallia; Balla, Itamar; Stanev, Teodor K.; Hersam, Mark C.; Stern, Nathaniel P.

2018-01-01

The ability to monitor and control distinct states is at the heart of emerging quantum technologies. The valley pseudospin in transition metal dichalcogenide (TMDC) monolayers is a promising degree of freedom for such control, with the optical Stark effect allowing for valley-selective manipulation of energy levels in WS2 and WSe2 using ultrafast optical pulses. Despite these advances, understanding of valley-sensitive optical Stark shifts in TMDCs has been limited by reflectance-based detection methods where the signal is small and prone to background effects. More sensitive polarization-based spectroscopy is required to better probe ultrafast Stark shifts for all-optical manipulation of valley energy levels. Here, we show time-resolved Kerr rotation to be a more sensitive probe of the valley-selective optical Stark effect in monolayer TMDCs. Compared to the established time-resolved reflectance methods, Kerr rotation is less sensitive to background effects. Kerr rotation provides a fivefold improvement in the signal-to-noise ratio of the Stark effect optical signal and a more precise estimate of the energy shift. This increased sensitivity allows for observation of an optical Stark shift in monolayer MoS2 that exhibits both valley and energy selectivity, demonstrating the promise of this method for investigating this effect in other layered materials and heterostructures.

Accelerator and Fusion Research Division annual report, fiscal year 1980, October 1979-September 1980

International Nuclear Information System (INIS)

1981-03-01

Research during October 1979 to September 1980 is summarized. Areas covered include: accelerator operations; positron-electron project; stochastic beam cooling; high-field superconducting magnets; accelerator theory; neutral beam sources; and heavy ion fusion

A comparative study of 99Tcm-MDP, 99Tcm(V)-DMSA and 99Tcm-Citrate in diagnosis of bone malignant tumors and bone/joint infections

International Nuclear Information System (INIS)

Wu Zhaozhong; Wu Boyi; Lin Wei; Wei Xueli; Wu Hengfu; Fan Ziwen; Ouyang Zhi; Wu Changwei; Yuan Gewen

2003-01-01

The purpose of this study was to assess the diagnostic value of scans with 99 Tc m (V)-dimercaptosuccinic acid (DMSA) to localize bone metastases and to evaluate the capability to diagnose bone/joint infections with scans using 99 Tc m -Citrate. Eighteen patients referred to bone metastases and eighteen patients referred to bone and joint infection were studied. In all patients, a bone scan of 99 Tc m -MDP was obtained initially. Subsequently, comparative scans with 99 Tc m (V)-DMSA and 99 Tc m -Citrate were conducted successively. Pathologic finding and/or microbiological finding, X-ray CT and/or MRI, and/or clinical follow-up (until symptoms disappeared) were considered to be proof of the presence of bone metastases and bone/joint infection. All of the eighteen patients with diagnosed bone metastases and of the eighteen patients with diagnosed bone and joint infection had positive 99 Tc m -MDP scintigraphy. The fifteen patients with diagnosed bone metastases and the fifteen patients with diagnosed bone/joint infection had increased 99 Tc m (V) -DMSA accumulation at certain areas matched with those shown in 99 Tc m -MDP scans, and only one patient with diagnosed bone metastases and the fifteen patients with diagnosed bone and joint infection had increased 99 Tc m -Citrate accumulation at certain areas matched with those shown in 99 Tc m -MDP scans. 99 Tc m -MDP scans show 64 bone lesions in the bone metastases while 49 lesions by the 99 Tc m (V)-DMSA scans and only one lesion by the 99 Tc m -Citrate scans respectively. And 99 Tc m -MDP scans show 22 bone lesions in the bone and joint infection while 17 lesions by the 99 Tc m (V)-DMSA imaging and 16 lesions by the 99 Tc m -Citrate imaging respectively. For bone metastases diagnosis, the sensitivity of 99 Tc m (V)-DMSA imaging and 99 Tc m -Citrate imaging were 76.56% and 1.56%, respectively, and the specificity were only 22.73% and 27.27%, respectively. For bone and joint infection diagnosis, the sensitivity of two

Generator of 99m Tc with MnO2 as support of 99 Mo

International Nuclear Information System (INIS)

Granados C, F.; Serrano G, J.

2002-01-01

The generator of 99m Tc with MnO 2 as support of 99 Mo was studied. By mean of static experiments the retention of 99 Mo in MnO 2 in function of the stirring time and of the p H value of the solution of 99 Mo. It was found that the 99 Mo presents 100% of retention in MnO 2 in the rank of p H 3-11 and the balance was reached before of 10 minutes. In dynamic conditions the retention of 99 Mo in MnO 2 at p H=5 was also higher: 99.72%. The generated 99m Tc can be separated from 99 Mo, adsorbed in MnO 2 packed in the column, using distilled water at p H=5 or NaCl solution at 0.9%. With saline solution the elution yields were greater than 80% and only an aliquot of 5 ml was necessary for obtaining this yield. The better results were obtained when the column was packed with 1 g of MnO 2 . The water and the saline solution were passed through of the column with a flux of 1.25 ml/min. (Author)

Four newly recorded species of Dryopteridaceae from Kashmir valley, India

Directory of Open Access Journals (Sweden)

SHAKOOR AHMAD MIR

2014-04-01

Full Text Available Mir SA, Mishra AK, Reshi ZA, Sharma MP. 2014. Four newly recorded species of Dryopteridaceae from Kashmir valley, India. Biodiversitas 15: 6-11. Habitat diversity, elevation, cloud cover, rainfall, seasonal and temperature variations have created many ideal sites for the luxuriant growth of pteridophytes in the Kashmir valley, yet all the regions of the valley have not been surveyed. In Kashmir valley the family Dryopteridaceae is represented by 31 species. During the recent extensive field surveys of Shopian district four more species viz., Dryopteris caroli-hopei Fraser-Jenkins, Dryopteris blanfordii subsp. nigrosquamosa (Ching Fraser-Jenkins, Dryopteris pulvinulifera (Bedd. Kuntze and Polystichum Nepalense (Spreng C. Chr. have been recorded for the first time from the valley. The taxonomic description, synonyms, distribution and photographs of each species are given in this article.

Preliminary estimates of spatially distributed net infiltration and recharge for the Death Valley region, Nevada-California

International Nuclear Information System (INIS)

Hevesi, J.A.; Flint, A.L.; Flint, L.E.

2002-01-01

A three-dimensional ground-water flow model has been developed to evaluate the Death Valley regional flow system, which includes ground water beneath the Nevada Test Site. Estimates of spatially distributed net infiltration and recharge are needed to define upper boundary conditions. This study presents a preliminary application of a conceptual and numerical model of net infiltration. The model was developed in studies at Yucca Mountain, Nevada, which is located in the approximate center of the Death Valley ground-water flow system. The conceptual model describes the effects of precipitation, runoff, evapotranspiration, and redistribution of water in the shallow unsaturated zone on predicted rates of net infiltration; precipitation and soil depth are the two most significant variables. The conceptual model was tested using a preliminary numerical model based on energy- and water-balance calculations. Daily precipitation for 1980 through 1995, averaging 202 millimeters per year over the 39,556 square kilometers area of the ground-water flow model, was input to the numerical model to simulate net infiltration ranging from zero for a soil thickness greater than 6 meters to over 350 millimeters per year for thin soils at high elevations in the Spring Mountains overlying permeable bedrock. Estimated average net infiltration over the entire ground-water flow model domain is 7.8 millimeters per year. To evaluate the application of the net-infiltration model developed on a local scale at Yucca Mountain, to net-infiltration estimates representing the magnitude and distribution of recharge on a regional scale, the net-infiltration results were compared with recharge estimates obtained using empirical methods. Comparison of model results with previous estimates of basinwide recharge suggests that the net-infiltration estimates obtained using this model may overestimate recharge because of uncertainty in modeled precipitation, bedrock permeability, and soil properties for

JENDL dosimetry file 99 (JENDL/D-99)

International Nuclear Information System (INIS)

Kobayashi, Katsuhei; Iwasaki, Shin

2002-01-01

The JENDL Dosimetry File 99 (JENDL/D-99), which is a revised version of the JENDL Dosimetry File 91 (JENDL/D-91), has been compiled and released for the determination of neutron flux and energy spectra. This work was undertaken to remove the inconsistency between the cross sections and their covariances in JENDL/D-91 since the covariances were mainly taken from IRDF-85 although the cross sections were based on JENDL-3. Dosimetry cross sections have been evaluated for 67 reactions on 47 nuclides together with covariances. The cross sections for 34 major reactions and their covariances were simultaneously generated, and the remaining 33 reaction data were mainly taken from JENDL/D-91. Latest measurements were taken into account in the evaluation. The resultant evaluated data are given in the neutron energy region below 20 MeV in both of point-wise and group-wise files in the ENDF-6 format. In order to confirm the reliability of the evaluated data, several integral tests have been carried out: comparisons with average cross sections measured in fission neutron fields, fast/thermal reactor spectra, DT neutron fields and Li(d,n) neutron fields. It was found from the comparisons that the cross sections calculated from JENDL/D-99 are generally in good agreement with the measured data. The contents of JENDL/D-99 and the results of the integral tests are described in this report. All of the dosimetry cross sections are shown in a graphical form in the Appendix. (author)

Status of {sup 99}Mo-{sup 99m}Tc production development by (n, {gamma}) reaction

Energy Technology Data Exchange (ETDEWEB)

Tsuchiya, Kunihiko; Kaminaga, Masanori; Ishihara, Masahiro; Kawamura, Hiroshi [Japan Atomic Energy Agency, Oarai Research and Development Center, Oarai, Ibaraki (Japan); Mutalib, Abdul [National Nuclear Energy Agency of Indonesia (BATAN), Tangerang (Indonesia); Chakrov, Petr [Institute of Nuclear Physics, National Nuclear Center of Republic of Kazakhstan (INP-NNC-RK), Almaty (Kazakhstan)

2012-03-15

Technetium-99m ({sup 99m}Tc) is one of the most commonly used radioisotopes in the field of nuclear medicine. As one of effective uses of the JMTR, JAEA has a plan to produce {sup 99}Mo by (n, {gamma}) method, a parent nuclide of {sup 99m}Tc. JAEA has performed R and D on production method of {sup 99}Mo-{sup 99m}Tc in JMTR cooperating with foreign organizations and relevant Japanese enterprises under the cooperation programs. In this paper, present status of R and D for production of {sup 99}Mo-{sup 99m}Tc in JMTR under international cooperation is introduced and constructions of the irradiation and PIE facilities at the JMTR site are also described. (author)

99mTc-EDTA and 99mTc-DTPA complexes as hydrological tracers

International Nuclear Information System (INIS)

Dominguez, J.; Borroto, J.; Nazco, J.; Perez, E.; Gamboa, R.; Cruz, J.

2002-01-01

The [ 99m Tc-DTPA] 2- and [ 99m Tc-EDTA] 1- were evaluated as radiotracers for short time hydrological studies. Their complex stability after labelling with 9.25 GBq of 99m Tc, the behaviour against pH variations, from 5 to 9, in simulated solutions and in natural river waters and the sorption of these compounds on the river sediments, were tested in laboratory experiments. Finally field double tracing experiments were carried out for each of labelling complexes and Rhodamine WT. From recovery calculations not losses of the 99m Tc activity were observed. The shape of the RTD curves of the [ 99m Tc-DTPA] 2- and [ 99m Tc-EDTA] 1 were quite similar to the Rhodamine Wt ones. May be concluded that both complexes behaved conservatively on the studied environmental conditions. (author)

Ventilation potential during the emissions survey in Toluca Valley, Mexico

Science.gov (United States)

Ruiz Angulo, A.; Peralta, O.; Jurado, O. E.; Ortinez, A.; Grutter de la Mora, M.; Rivera, C.; Gutierrez, W.; Gonzalez, E.

2017-12-01

During the late-spring early-summer measurements of emissions and pollutants were carried out during a survey campaign at four different locations within the Toluca Valley. The current emissions inventory typically estimates the generation of pollutants based on pre-estimated values representing an entire sector function of their activities. However, those factors are not always based direct measurements. The emissions from the Toluca Valley are rather large and they could affect the air quality of Mexico City Valley. The air masses interchange between those two valleys is not very well understood; however, based on the measurements obtained during the 3 months campaign we looked carefully at the daily variability of the wind finding a clear signal for mountain-valley breeze. The ventilation coefficient is estimated and the correlations with the concentrations at the 4 locations and in a far away station in Mexico City are addressed in this work. Finally, we discuss the implication of the ventilation capacity in air quality for the system of Valleys that include Mexico City.

Optimization of the 99m Tc generator with hydrotalcite as support of 99 Mo

International Nuclear Information System (INIS)

Aranda O, N.

2004-01-01

In the last years, in the laboratories of the National Institute of Nuclear Investigations (ININ) its have been investigating to the hydrotalcite like a material of support of the 99 Mo with the purpose of developing a new technetium generator. During the development of the investigations it has been demonstrated that when putting in contact to the HTC with an aqueous solution that contains anions of any type, the HTC re hydrate and the structure is regenerated to laminate of the hydrotalcite. If the present anions in the solution are molybdate anions (MoO 4 2- ), these anions passed to be part of the structure of the hydrotalcite (HT-MoO 4 ). These anions can contain, in turn, 99 Mo in their composition ( 99 MoO 4 2- ) and equally they can pass to be part of the structure of the hydrotalcite forming the HT- 99 MoO 4 . When the HT- 99 MoO 4 is packed in a column, the 99m Tc that it takes place when decaying the 99 Mo radioactively can separate the column using aqueous solution of NaCl. This way, in previous studies (Serrano, 2000) it was found that the aqueous solution of NaCl to 0.5% it is the but appropriate for elutriate at the 99m Tc from the column the yield of the elution of the 99m Tc was since high (98%) in the first elution, and the radionuclide contamination caused by the presence of 99 Mo in the eluate it was low ( 4 2- for gram of HTC). These facts, standing out the high capacity of the HTC to retain molybdate ions, they drove from a direct way to investigate the optimization of the generator of 99m Tc, with hydrotalcite like support of the 99 Mo, using 99 Mo of low specific activity. This finishes radioactive material it can be obtained by the irradiation of the 98 Mo (in the chemical form of MoO 3 or (NH 4 ) 2 MoO 4 ), with a flow of thermal neutrons in the nuclear reactor TRIGA Mark lll that one has in the Nuclear Center N abor Carrillo Flores . The technetium generators with alumina like support of the 99 Mo use 99 Mo of high specific activity

Fitness-valley crossing with generalized parent-offspring transmission.

Science.gov (United States)

Osmond, Matthew M; Otto, Sarah P

2015-11-01

Simple and ubiquitous gene interactions create rugged fitness landscapes composed of coadapted gene complexes separated by "valleys" of low fitness. Crossing such fitness valleys allows a population to escape suboptimal local fitness peaks to become better adapted. This is the premise of Sewall Wright's shifting balance process. Here we generalize the theory of fitness-valley crossing in the two-locus, bi-allelic case by allowing bias in parent-offspring transmission. This generalization extends the existing mathematical framework to genetic systems with segregation distortion and uniparental inheritance. Our results are also flexible enough to provide insight into shifts between alternate stable states in cultural systems with "transmission valleys". Using a semi-deterministic analysis and a stochastic diffusion approximation, we focus on the limiting step in valley crossing: the first appearance of the genotype on the new fitness peak whose lineage will eventually fix. We then apply our results to specific cases of segregation distortion, uniparental inheritance, and cultural transmission. Segregation distortion favouring mutant alleles facilitates crossing most when recombination and mutation are rare, i.e., scenarios where crossing is otherwise unlikely. Interactions with more mutable genes (e.g., uniparental inherited cytoplasmic elements) substantially reduce crossing times. Despite component traits being passed on poorly in the previous cultural background, small advantages in the transmission of a new combination of cultural traits can greatly facilitate a cultural transition. While peak shifts are unlikely under many of the common assumptions of population genetic theory, relaxing some of these assumptions can promote fitness-valley crossing. Copyright © 2015 Elsevier Inc. All rights reserved.

Evaluation of 99Mo/99mTc generator experiment using PZC material and irradiated natural molybdenum

International Nuclear Information System (INIS)

Khongpetch, P.; Chingjit, S.; Dangprasert, M.; Rangsawai, W.; Virawat, N.

2006-01-01

Technetium-99m ( 99m Tc) is the most widely used radioisotope in nuclear medicine, accounting for more than 80% of all diagnostic nuclear medicine procedure. 99m Tc is almost exclusively produced from the decay of its parent molybdenum-99 ( 99 Mo). The present sources of 99 Mo are research reactors by using the (n, γ) nuclear reaction with natural molybdenum, resulting in inexpensive but low specific activity 99 Mo, or by neutron-induced fission of uranium-235, which result in expensive but high specific activity 99 Mo. The technology requirement for processing of 99 Mo from the (n, γ) 'activation method' is rather simple, and is within the reach of most developing countries operating research reactors. In the fission method' the technological and infrastructure requirements are some complex, and possibly can be sustained only by countries with advanced nuclear technology. To overcome these difficulties, Japan Atomic Energy Research Institute (JAERI) and KAKEN company have developed alternative technology for 99 Mo/ 99m Tc generator by using a molybdenum absorbent called Poly Zirconium compound (PZC) and irradiated natural molybdenum. The paper describes experiments for evaluation the performance of PZC as a column packing material for 99 Mo/ 99m Tc generator from (n, γ) 99 Mo. (author)

Subglacial tunnel valleys in the Alpine foreland: an example from Bern, Switzerland

Energy Technology Data Exchange (ETDEWEB)

Duerst Stucki, M.; Reber, R.; Schlunegger, F.

2010-12-15

The morphology of the Alpine and adjacent landscapes is directly related to glacial erosion and associated sediment transport. Here we report the effects of glacio-hydrologic erosion on bedrock topography in the Swiss Plateau. Specifically, we identify the presence of subsurface valleys beneath the city of Bern and discuss their genesis. Stratigraphic investigations of more than 4'000 borehole data within a 430 km{sup 2}-large area reveal the presence of a network of >200 m-deep and 1'000 m-wide valleys. They are flat floored with steep sided walls and are filled by Quaternary glacial deposits. The central valley beneath Bern is straight and oriented towards the NNW, with valley flanks more than 20 {sup o} steep. The valley bottom has an irregular undulating profile along the thalweg, with differences between sills and hollows higher than 50-100 m over a reach of 4 km length. Approximately 500 m high bedrock highlands flank the valley network. The highlands are dissected by up to 80 m-deep and 500 m-broad hanging valleys that currently drain away from the axis of the main valley. We interpret the valleys beneath the city of Bern to be a tunnel valley network which originated from subglacial erosion by melt water. The highland valleys served as proglacial meltwater paths and are hanging with respect to the trunk system, indicating that these incipient highland systems as well as the main gorge beneath Bern formed by glacial melt water under pressure. (authors)

Ozone Laminae and Their Entrainment Into a Valley Boundary Layer, as Observed From a Mountaintop Monitoring Station, Ozonesondes, and Aircraft Over California's San Joaquin Valley

Science.gov (United States)

Faloona, I. C.; Conley, S. A.; Caputi, D.; Trousdell, J.; Chiao, S.; Eiserloh, A. J., Jr.; Clark, J.; Iraci, L. T.; Yates, E. L.; Marrero, J. E.; Ryoo, J. M.; McNamara, M. E.

2016-12-01

The San Joaquin Valley of California is wide ( 75 km) and long ( 400 km), and is situated under strong atmospheric subsidence due, in part, to the proximity of the midlatitude anticyclone of the Pacific High. The capping effect of this subsidence is especially prominent during the warm season when ground level ozone is a serious air quality concern across the region. While relatively clean marine boundary layer air is primarily funneled into the valley below the strong subsidence inversion at significant gaps in the upwind Coast Range mountains, airflow aloft also spills over these barriers and mixes into the valley from above. Because this transmountain flow occurs under the influence of synoptic subsidence it tends to present discrete, laminar sheets of differing air composition above the valley boundary layer. Meanwhile, although the boundary layers tend to remain shallow due to the prevailing subsidence, orographic and anabatic venting of valley boundary layer air around the basin whips up a complex admixture of regional air masses into a "buffer layer" just above the boundary layer (zi) and below the lower free troposphere. We present scalar data of widely varying lifetimes including ozone, methane, NOx, and thermodynamic observations from upwind and within the San Joaquin Valley to better explain this layering and its subsequent erosion into the valley boundary layer via entrainment. Data collected at a mountaintop monitoring station on Chews Ridge in the Coast Range, by coastal ozonesondes, and aircraft are analyzed to document the dynamic layering processes around the complex terrain surrounding the valley. Particular emphasis will be made on observational methods whereby distal ozone can be distinguished from the regional ozone to better understand the influence of exogenous sources on air quality in the valley.

Geomorphological hazards in Swat valley, Pakistan

International Nuclear Information System (INIS)

Usman, A.

1999-01-01

This study attempts to describe, interpret and analyze, in depth, the varied geomorphological hazards and their impacts prevailing in the swat valley locate in the northern hilly and mountainous regions of Pakistan. The hills and mountains re zones of high geomorphological activity with rapid rates of weathering, active tectonic activities, abundant precipitation, rapid runoff and heavy sediment transport. Due to the varied topography, lithology, steep slope, erodible soil, heavy winter snowfall and intensive rainfall in the spring and summer seasons, several kinds of geomorphological hazards, such as geomorphic gravitational hazards, Fluvial hazards, Glacial hazards, Geo tectonic hazards, are occurring frequently in swat valley. Amongst them, geomorphic gravitational hazards, such as rock fall rock slide, debris slide mud flow avalanches, are major hazards in mountains and hills while fluvial hazards and sedimentation are mainly confined to the alluvial plain and lowlands of the valley. The Getechtonic hazards, on the other hand, have wide spread distribution in the valley the magnitude and occurrence of each king of hazard is thus, varied according to intensity of process and physical geographic environment. This paper discusses the type distribution and damage due to the various geomorphological hazards and their reduction treatments. The study would to be of particular importance and interest to both natural and social scientists, as well as planner, environmentalists and decision-makers for successful developmental interventions in the region. (author)

Determination of Tc-99 in radioactive wastes; Determinacion de Tc-99 en desechos radiactivos

Energy Technology Data Exchange (ETDEWEB)

Rivera S, A. A.

2015-07-01

Tc-99 is a fission product and one of the most important radionuclides from the view point of safety assessment for the disposal of radioactive waste because of its long half-life (2.1 x 10{sup 5} years) and high mobility in soil-water systems, if this is released into the environment in significant quantities can concentrate on plants and animals. Tc-99 is a pure beta emitter with a maximum energy of 292 KeV, so their quantification imposes destructive methods to be analyzed by liquid scintillation. Therefore the quantification of Tc-99 in ion exchange resins requires of the mineralization of these and separation of Tc-99 of other radioisotopes present in the resin. Therefore the object of this thesis is to develop a quantification method of Tc-99 content in spent exchange resins. So in order to track the behavior of technetium during digestion exchange resins and radiochemical separation, given its high volatility, in this work the {sup 99m}Tc is used. To determine the degree of mineralization of the resins, an analysis was performed by chromatography. Subsequently the method used to determine the percentage of {sup 99m}Tc aerosolized during mineralization of resin is described. After the method for the radiochemical separation of {sup 99m}Tc is presented by liquid-liquid extraction using crown ether as extractant; for this testing was performed by varying the molarity of the extractant, the ratio of solvent extractant, type of digestion of the resin and the presence of Sr-85, in order to study the behavior of {sup 99m}Tc in the presence of this radioisotope. Finally, a track beta spectra of a sample of {sup 99m}Tc eluted from a generator {sup 99}Mo/{sup 99m}Tc function of time was performed. (Author)

A new Proposal to Mexico Valley Zonification

Science.gov (United States)

Flores-Estrella, H. C.; Yussim, S.; Lomnitz, C.

2004-12-01

The effects of the Michoacan earthquake (19th September, 1985, Mw 8.1) in Mexico City caused a significant change in the political, social and scientific history, as it was considered the worst seismic disaster ever lived in Mexico. Since then, numerous efforts have been made to understand and determine the parameters that caused the special features registered. One of these efforts had began on 1960 with the work by Marsal and Masari, who published the Mexico Valley seismological and geotechnical zonification (1969), based on gravimetric and shallow borehole data. In this work, we present a revision of the studies that proposed the zonification, a description of the valley geology, and basing on it we propose a new zonification for Mexico Valley.

The value of the hepatobiliaric function scintigraphy with Tc-99m-DAIDA for post-operative biliary tract function diagnosis

International Nuclear Information System (INIS)

Ast, G.

1982-01-01

The goal of this work was the examination of the value of biliary tract scintigraphy with 99m Tc DAIDA for post-operative supervision after biliary tract operations. The subjects were made up of 22 patients, who between 1969 and 1980 had undergone a choledochus revision with the insertion of a T drainage. In all cases with cholestase-specific laboratory findings the intra- and extrahepatic biliary tracts were expanded and in 71% of the cases were combined with an organically dependent drainage retardation which was scintigraphically proven. The proof of an organically dependent drainage retardation in scintigraphy coincided almost always with expanded biliary paths and in almost half the cases with blockage-specific changes in the laboratory values. Conclusion: By patients with operations on the biliary tracts the indication for biliary tract scintigraphy with 99m Tc DAIDA is always given, if with cholestase- oder liver-specifically changed laboratory values no concretions using sonography or preliminary radiographs could be proven. (TRV) [de

Technetium-99 levels in pertechnetate solutions from (n,γ) and (n,f) molybdenum-99 generators

International Nuclear Information System (INIS)

Moore, P.W.

1983-04-01

There is increasing evidence that, in some radiopharmaceutical kits, Tc-99 has an adverse effect on the imaging and labelling performance of Tc-99m. For example, labelling efficiency with red blood cells can be affected when 99/99m ratios exceed about 4:1. The 99/99m ratio in a target is about 13.5:1 after a seven-day irradiation in a nuclear reactor. The ratio increases slightly during the time needed for processing. With the chromatographic generators used in hospitals, up to 90 hours may elapse between the final wash stage of manufacture and the first elution, during which time, 99/99m ratios can increase to about 90:1. If elution efficiencies are high and the time between elutions is between 12 and 24 hours, ratios in the generator, hence in the eluates, may actually increase with each elution. In the case of ready-to-inject pertechnetate solutions, the critical time at which 99/99m ratios increase rapidly is the time between elution and use. If production conditions are poor, ratios may increase to more than 600:1 by the time of use. With better conditions and production schedules Tc-99 levels at the time of use are comparable to those from chromatographic generators

Hybrid spin and valley quantum computing with singlet-triplet qubits.

Science.gov (United States)

Rohling, Niklas; Russ, Maximilian; Burkard, Guido

2014-10-24

The valley degree of freedom in the electronic band structure of silicon, graphene, and other materials is often considered to be an obstacle for quantum computing (QC) based on electron spins in quantum dots. Here we show that control over the valley state opens new possibilities for quantum information processing. Combining qubits encoded in the singlet-triplet subspace of spin and valley states allows for universal QC using a universal two-qubit gate directly provided by the exchange interaction. We show how spin and valley qubits can be separated in order to allow for single-qubit rotations.

Summary of recent research in Long Valley Caldera, California

Science.gov (United States)

Sorey, M.L.; McConnell, V.S.; Roeloffs, E.

2003-01-01

Since 1978, volcanic unrest in the form of earthquakes and ground deformation has persisted in the Long Valley caldera and adjacent parts of the Sierra Nevada. The papers in this special volume focus on periods of accelerated seismicity and deformation in 1980, 1983, 1989-1990, and 1997-1998 to delineate relations between geologic, tectonic, and hydrologic processes. The results distinguish between earthquake sequences that result from relaxation of existing stress accumulation through brittle failure and those in which brittle failure is driven by active intrusion. They also indicate that in addition to a relatively shallow (7-10-km) source beneath the resurgent dome, there exists a deeper (???15-km) source beneath the south moat. Analysis of microgravimety and deformation data indicates that the composition of the shallower source may involve a combination of silicic magma and hydrothermal fluid. Pressure and temperature fluctuations in wells have accompanied periods of crustal unrest, and additional pressure and temperature changes accompanying ongoing geothermal power production have resulted in land subsidence. The completion in 1998 of a 3000-m-deep drill hole on the resurgent dome has provided useful information on present and past periods of circulation of water at temperatures of 100-200??C within the crystalline basement rocks that underlie the post-caldera volcanics. The well is now being converted to a permanent geophysical monitoring station. ?? 2003 Elsevier B.V. All rights reserved.

Scintigraphic findings on 99mTc-MDP, 99mTc-sestamibi and 99mTc-HMPAO images in Gaucher's disease

International Nuclear Information System (INIS)

Mariani, G.; Molea, N.; La Civita, L.; Porciello, G.; Lazzeri, E.; Ferri, C.

1996-01-01

We report here on the use of the lipophilic cationic complex technetium-99m sestamibi ( 99m Tc-MIBI), employed as an indicator of increased cellular density and metabolic activity, to evaluate Gaucher cell infiltrates in the bone marrow; 99m Tc-hexametazime ( 99m Tc-HMPAO) was also employed, as a pure indicator of lipidic infiltration in the bone marrow. A 67-year-old patient with known type 1 Gaucher's disease presented with a painful left hip and knee and difficulty in gait subsequent to traumatic fracture of the left femoral neck that had required implant of a fixation screw-plaque. Bone scan with 99m Tc-methylene diphosphonate revealed reduced uptake at the distal metaphyseal-epiphyseal femoral region. In addition, whole-body maps and spot-view acquisitions of the thighs and legs were recorded at both 30 min and 2.5 h after the injection of 99m Tc-MIBI: the scintigraphic pattern clearly showed increased uptake at several sites involved by Gaucher deposits in the bone marrow (both knees, with variable intensity in different areas), matching the bone changes detected by conventional x-ray. The target to non-target ratios slowly decreased with time, from an average value of 2.25 in the early scan to an average value of 2 in the delayed scan. The lipid-soluble agent 99m Tc-HMPAO exhibited a superimposable scintigraphic pattern of accumulation at the involved sites, though with lower target to non-target ratios (1.27-1.48). The results obtained in this patient suggest a potential role of 99m Tc-MIBI in the scintigraphic evaluation of Gaucher's lipid deposits in the bone marrow. If the results are confirmed in other patients, this radiopharmaceutical would offer clear advantages over 133 Xe because of its wider availability and greater practicality (i.v. administration of 99m Tc-MIBI versus inhalation of 133 Xe, and use of a single gamma camera instead of two as with 133 Xe). (orig.). With 3 figs

Localization diagnosis of hyperfunctional parathyroid gland using 99Tcm-MIBI and 99TcmO4- imaging

International Nuclear Information System (INIS)

Zhang Fenru; Deng Huixing; Duan Xiaoyi; Xue Jianjun; Gao Rui

2010-01-01

Objective: To study the localization diagnosis value of nuclide imaging by 99 Tc m -MIBI double phase parathyroid combined with 99 Tc m O 4 - thyroid imaging in patients with hyperparathyroidism (HPT). Methods: Patients with primary HPT were 36 cases. Control groups were 10 cases with thyroid disease. Early phase imaging was performed in 15 minute after injecting imaging agent 99 Tc m -MIBI. Delay phase imaging was performed in 2 hours. 36 HPT patients and 10 cases control groups were also performed 99 Tc m O 4 - thyroid imaging 24 hours later. The two kinds of imaging were compared with each other, were analyzed, and were underwent imaging subtracted by eyes and imaging results judgment. Results: In 36 cases of HPT patients, 34 cases showed positive result imaging with 99 Tc m -MIBI/ 99 Tc m O 4 - imaging. 2 cases showed false negative result. Positive rate was 94.44 % with 99 Tc m -MIBI/ 99 Tc m O 4 - imaging. The positive result imaging showed abnormal increased uptake of 99 Tc m -MIBI. In 36 cases of HPT patients, 12 cases showed positive result with single 99 Tc m -MIBI imaging. 4 cases showed false negative imaging. 20 cases showed ambiguous positive results. Positive rate was 88.89% (55.56% was ambiguous positive results) with single 99 Tc m -MIBI imaging. In 10 cases control groups, 3 cases showed false positive results with single 99 Tc m -MIBI imaging. 1 case showed ambiguous false positive results. No case showed false positive result with 99 Tc m -MIBI/ 99 Tc m O 4 - imaging. Conclusion: 99 Tc m -MIBI parathyroid double phase imaging combined with 99 Tc m O 4 - thyroid imaging have important value for diagnoses and localization of hyperparathyroidism. 99 Tc m -MIBI/ 99 Tc m O 4 - imaging have higher positive rate and higher specificity than single 99 Tc m -MIBI imaging for diagnoses and localization of hyperfunction parathyroid gland. (authors)

Bibliography of Technical Publications and Papers, October 1979 - September 1980

Science.gov (United States)

1980-11-01

technological procedures affecting quality of radappertized chicken rolls. Institute of Food Technolo- gists, New Orleans, LA, 9-11 June 1980. 93...temperature survey of ginger beef pot roast production at a Central Food Preparation Facility. J. Food Prot., 43(4): 292-294 (1980). 180. REESE, E. T...low-dose irradiated chicken skins. Interagency Botulism Research Coordinating Coummittee, Milford, CT, 8-9 October 1980. 207. CALLO, B. Protoplast

Joint annual report 1980

International Nuclear Information System (INIS)

Hohmuth, K.

1981-05-01

Results of research work carried out at the ZfK Rossendorf in 1980 are presented in individual summaries covering the following topics: nuclear reactions, nuclear spectroscopy, nuclear theory, applied methods of nuclear physics, accelerators, nuclear electronics and methods, and computer codes. A list of publications is included

Graphene valley pseudospin filter using an extended line defect

Science.gov (United States)

Gunlycke, Daniel; White, Carter

2011-03-01

Although graphene exhibits excellent electron and thermal transport properties, it does not have an intrinsic band gap, required to use graphene as a replacement material for silicon and other semiconductors in conventional electronics. The band structure of graphene with its two cones near the Fermi level, however, offers opportunities to develop non-traditional applications. One such avenue is to exploit the valley degeneracy in graphene to develop valleytronics. A central component in valleytronics is the valley filter, just as the spin filter is central in spintronics. Herein, we present a two-dimensional valley filter based on scattering of electrons and holes off a recently observed extended line defect [Nat. Nanotech.5, 326 (2010)] within graphene. The transmission probability depends strongly on the valley pseudospin and the angle of incidence of the incident quasiparticles. Quasiparticles arriving at the line defect at a high angle of incidence lead to a valley polarization of the transmitted beam that is near 100 percent. This work was supported by ONR, directly and through NRL.

Hydrological responses to channelization and the formation of valley plugs and shoals

Science.gov (United States)

Pierce, Aaron R.; King, Sammy L.

2017-01-01

Rehabilitation of floodplain systems focuses on restoring interactions between the fluvial system and floodplain, however, there is a paucity of information on the effects of valley plugs and shoals on floodplain hydrological processes. We investigated hydrologic regimes in floodplains at three valley plug sites, two shoal sites, and three unchannelized sites. Valley plug sites had altered surface and sub-surface hydrology relative to unchannelized sites, while only sub-surface hydrology was affected at shoal sites. Some of the changes were unexpected, such as reduced flood duration and flood depth in floodplains associated with valley plugs. Our results emphasize the variability associated with hydrologic processes around valley plugs and our rudimentary understanding of the effects associated with these geomorphic features. Water table levels were lower at valley plug sites compared to unchannelized sites, however, valley plug sites had a greater proportion of days when water table inundation was above mean root collar depth than both shoal and unchannelized sites as a result of lower root collar depths and higher deposition rates. This study has provided evidence that valley plugs can affect both surface and sub-surface hydrology in different ways than previously thought and illustrates the variability in hydrological responses to valley plug formation.

1980/1981 activities report

International Nuclear Information System (INIS)

1982-03-01

The National Uranium Resource Evaluation (NURE) had as its major goal the development of reliable, timely, and comprehensive estimates of the uranium resources of the United States. Geologic, geochemical, geophysical, and other data were acquired which contributed to assessment of the distribution and magnitude of these uranium resources, as well as to determination of areas favorable for the occurrence of uranium and to establishment of potential resource estimates. The data-collection phase of the NURE program ended September 30, 1980. The NURE program was organized around six major activity elements: Quadrangle Evaluation, Data Acquisition, Resource Assessment, Geologic Studies, Technology Applications, and Mineral Economics. This fifth activities report presents summary results on work performed during the period 1980/1981 in each of these element areas, together with appendices that cite individual project data and resulting reports. By the end of 1981, evaluation of an additional 28 quadrangles had been completed, bringing to 163 the total number covered by the NURE program

Optimization of the {sup 99m} Tc generator with hydrotalcite as support of {sup 99} Mo; Optimizacion del generador de {sup 99m} Tc con hidrotalcita como soporte del {sup 99} Mo

Energy Technology Data Exchange (ETDEWEB)

Aranda O, N

2004-07-01

In the last years, in the laboratories of the National Institute of Nuclear Investigations (ININ) its have been investigating to the hydrotalcite like a material of support of the {sup 99} Mo with the purpose of developing a new technetium generator. During the development of the investigations it has been demonstrated that when putting in contact to the HTC with an aqueous solution that contains anions of any type, the HTC re hydrate and the structure is regenerated to laminate of the hydrotalcite. If the present anions in the solution are molybdate anions (MoO{sub 4}{sup 2-}), these anions passed to be part of the structure of the hydrotalcite (HT-MoO{sub 4}). These anions can contain, in turn, {sup 99} Mo in their composition ({sup 99}MoO{sub 4}{sup 2-}) and equally they can pass to be part of the structure of the hydrotalcite forming the HT-{sup 99}MoO{sub 4}. When the HT-{sup 99}MoO{sub 4} is packed in a column, the {sup 99m}Tc that it takes place when decaying the {sup 99}Mo radioactively can separate the column using aqueous solution of NaCl. This way, in previous studies (Serrano, 2000) it was found that the aqueous solution of NaCl to 0.5% it is the but appropriate for elutriate at the {sup 99m}Tc from the column the yield of the elution of the {sup 99m}Tc was since high (98%) in the first elution, and the radionuclide contamination caused by the presence of {sup 99}Mo in the eluate it was low (<0.01%). In this investigation it was also found that the HTC has a high capacity to retain molybdate ions (255.1 mg of ions MoO{sub 4}{sup 2-} for gram of HTC). These facts, standing out the high capacity of the HTC to retain molybdate ions, they drove from a direct way to investigate the optimization of the generator of {sup 99m}Tc, with hydrotalcite like support of the {sup 99}Mo, using {sup 99}Mo of low specific activity. This finishes radioactive material it can be obtained by the irradiation of the {sup 98}Mo (in the chemical form of MoO{sub 3} or (NH{sub 4

Evaluation of the absorbed dose to the kidneys due to Tc{sup 99m} (DTPA) / Tc{sup 99m} (Mag3) and Tc{sup 99m} (Dmsa); Evaluacion de la dosis absorbida en los rinones debido al Tc{sup 99m} (DTPA) / Tc{sup 99m} (MAG3) y Tc{sup 99m} (DMSA)

Energy Technology Data Exchange (ETDEWEB)

Vasquez A, M.; Murillo C, F.; Castillo D, C.; Rocha J, J.; Sifuentes D, Y.; Sanchez S, P. [Universidad Nacional de Trujillo, Av. Juan Pablo II s/n, Trujillo (Peru); Idrogo C, J.; Marquez P, F., E-mail: marvva@hotmail.com [Instituto Nacional de Enfermedades Neoplasicas, Av. Angamos 2520, Lima (Peru)

2015-10-15

The absorbed dose in the kidneys of adult patients has been assessed using the biokinetics of radiopharmaceuticals containing Tc{sup 99m} (DTPA) / Tc{sup 99m} (Mag3) or Tc{sup 99m} (Dmsa).The absorbed dose was calculated using the formalism MIRD and the Cristy-Eckerman representation for the kidneys. The absorbed dose to the kidneys due to Tc{sup 99m} (DTPA) / Tc{sup 99m} (Mag3), are given by 0.00466 mGy.MBq{sup -1} / 0.00339 mGy.MBq{sup -1}. Approximately 21.2% of the absorbed dose is due to the bladder (content) and the remaining tissue, included in biokinetics of Tc{sup 99m} (DTPA) / Tc{sup 99m} (Mag3). The absorbed dose to the kidneys due to Tc{sup 99m} (Dmsa) is 0.17881 mGy.MBq{sup -1}. Here, 1.7% of the absorbed dose is due to the bladder, spleen, liver and the remaining tissue, included in biokinetics of Tc{sup 99m} (Dmsa). (Author)

Rechargeable sup(99)MO/sup(99m)TC generator system

International Nuclear Information System (INIS)

Thornton, A.K.; Cerone, F.E.

1980-01-01

A rechargeable radioisotope generator system is described in which the transfer of the parent isotope, molybdenum 99, can be affected safely and easily. Part of the system consists of a shielded shipping vial for the parent isotope. The generator consists of an alumina column upon which molybdenum 99 may be adsorbed and from which technetium 99m may be eluted. The generator is shipped as a cold package to the user and is charged as needed. A transfer mechanism is incorporated in the shipping shield, which allows the septum of the vial to be pierced and the contents to be transferred to the generator essentially automatically. (LL)

The California Valley grassland

Science.gov (United States)

Keeley, J.E.; Schoenherr, Allan A.

1990-01-01

Grasslands are distributed throughout California from Oregon to Baja California Norte and from the coast to the desert (Brown 1982) (Figure 1). This review will focus on the dominant formation in cismontane California, a community referred to as Valley Grassland (Munz 1959). Today, Valley Grassland is dominated by non-native annual grasses in genera such as Avena (wild oat), Bromus (brome grass), and Hordeum (barley), and is often referred to as the California annual grassland. On localized sites, native perennial bunchgrasses such as Stipa pultra (purple needle grass) may dominate and such sites are interpreted to be remnants of the pristine valley grassland. In northwestern California a floristically distinct formation of the Valley Grassland, known as Coast Prairie (Munz 1959) or Northern Coastal Grassland (Holland and Keil 1989) is recognized. The dominant grasses include many native perennial bunchgrasses in genera such as Agrostis, Calamagrostis, Danthonia, Deschampsia, Festuca, Koeleria and Poa (Heady et al. 1977). Non-native annuals do not dominate, but on some sites non-native perennials like Anthoxanthum odoratum may colonize the native grassland (Foin and Hektner 1986). Elevationally, California's grasslands extend from sea level to at leas 1500 m. The upper boundary is vague because montane grassland formations are commonly referred to as meadows; a community which Munz (1959) does not recognize. Holland and Keil (1989) describe the montane meadow as an azonal community; that is, a community restricted not so much to a particular climatic zone but rather controlled by substrate characteristics. They consider poor soil-drainage an over-riding factor in the development of montane meadows and, in contrast to grasslands, meadows often remain green through the summer drought. Floristically, meadows are composed of graminoids; Cyperaceae, Juncaceae, and rhizomatous grasses such as Agropyron (wheat grass). Some bunchgrasses, such as Muhlenbergia rigens, are

Mathematical methods in the solution of the the Hamilton-Darwin and the Takagi-Taupin equations

International Nuclear Information System (INIS)

Werner, S.A.; Berliner, R.R.; Arif, M.; Missouri Univ., Columbia

1986-01-01

The diffraction of neutrons by a single crystal is intrinsically a multiple scattering problem. For an ideally imperfect mosaic crystal the Hamilton-Darwin transfer equations describe the coupling of the incident and diffracted beams; whereas, for a perfect crystal one must use the dynamical theory of diffraction, which can be recast in the form of two coupled partial differential equations commonly referred to as the Takagi-Taupin equations. From a mathematical point of view these two problems are equivalent, although the physical manifestations of the solutions are quite different. For the occasion of Professor Shull's seventieth birthday celebration, we bring together in this paper some of the mathematical techniques which we have found useful in elucidating the subtleties of the Bragg diffraction of neutron by crystals. (orig.)

Renewed inflation of Long Valley Caldera, California (2011 to 2014)

Science.gov (United States)

Montgomery-Brown, Emily; Wicks, Chuck; Cervelli, Peter F.; Langbein, John O.; Svarc, Jerry L.; Shelly, David R.; Hill, David P.; Lisowski, Michael

2015-01-01

Slow inflation began at Long Valley Caldera in late 2011, coinciding with renewed swarm seismicity. Ongoing deformation is concentrated within the caldera. We analyze this deformation using a combination of GPS and InSAR (TerraSAR-X) data processed with a persistent scatterer technique. The extension rate of the dome-crossing baseline during this episode (CA99 to KRAC) is 1 cm/yr, similar to past inflation episodes (1990–1995 and 2002–2003), and about a tenth of the peak rate observed during the 1997 unrest. The current deformation is well modeled by the inflation of a prolate spheroidal magma reservoir ∼7 km beneath the resurgent dome, with a volume change of ∼6 × 106 m3/yr from 2011.7 through the end of 2014. The current data cannot resolve a second source, which was required to model the 1997 episode. This source appears to be in the same region as previous inflation episodes, suggesting a persistent reservoir.

The preparation and biodistribution of a new 99Tcm-nitrito complex 99TcmN-MIBI

International Nuclear Information System (INIS)

Zhang Xianzhong; Wang Xuebin; Zhang Junbo

1997-01-01

The technetium-99m nitrito intermediate is synthesized by using SnCl 2 ·2H 2 O as reductant, and the complex 99 Tc m N-MIBI is obtained through ligand exchange reaction. The labelling yield of 99 Tc m N-MIBI is over 95% by TLC. The conditions of preparing 99 Tc m N-MIBI are optimized. Results of stability and partition coefficient of 99 Tc m N-MIBI indicate that the complex is lipophilic and stable over 10 h at room temperature. The biodistribution of 99 Tc m N-MIBI in mice shows high myocardium uptake, and rather rapid clearance. For 5-min post-injection the heart-to-blood, heart-to-lung and heart-to-liver ratios are 3.18, 1.72 and 1.42, respectively. The new complex may be suitable for instant myocardial imaging. 99 Tc m N-MIBI has significant different biodistribution characteristics from 99 Tc m -MIBI. Based on these promising properties, 99 Tc m N-MIBI should be a new potential myocardial perfusion imaging agent

Radioactive waste control at the reprocessing facility in fiscal 1980

International Nuclear Information System (INIS)

1982-01-01

At the fuel reprocessing facility of the Power Reactor and Nuclear Fuel Development Corporation (PNC), the release of radioactive gaseous and liquid wastes are controlled so as not to exceed the specific levels. Concentrated low and high level liquid wastes, sludge, etc. are contained in storage tanks. Low and high level solid wastes are stored in appropriate containers. In fiscal 1980 (April to March), the release of gaseous and liquid wastes was below the specific levels (as in the previous years). Based on the report made by PNC in accordance with the law concerning the regulation of reactors, etc., the following data are presented in tables: the released quantity of radioactive gaseous and liquid wastes in fiscal 1980, the cumulative stored quantity of radioactive liquid wastes up to fiscal 1980; the cumulative stored quantity of radioactive solid wastes up to fiscal 1980 and the quantity of the same stored in fiscal 1980. (J.P.N.)

Groundwater quality in the Antelope Valley, California

Science.gov (United States)

Dawson, Barbara J. Milby; Belitz, Kenneth

2012-01-01

Groundwater provides more than 40 percent of California’s drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project of the GAMA Program provides a comprehensive assessment of the State’s groundwater quality and increases public access to groundwater-quality information. Antelope Valley is one of the study areas being evaluated. The Antelope study area is approximately 1,600 square miles (4,144 square kilometers) and includes the Antelope Valley groundwater basin (California Department of Water Resources, 2003). Antelope Valley has an arid climate and is part of the Mojave Desert. Average annual rainfall is about 6 inches (15 centimeters). The study area has internal drainage, with runoff from the surrounding mountains draining towards dry lakebeds in the lower parts of the valley. Land use in the study area is approximately 68 percent (%) natural (mostly shrubland and grassland), 24% agricultural, and 8% urban. The primary crops are pasture and hay. The largest urban areas are the cities of Palmdale and Lancaster (2010 populations of 152,000 and 156,000, respectively). Groundwater in this basin is used for public and domestic water supply and for irrigation. The main water-bearing units are gravel, sand, silt, and clay derived from surrounding mountains. The primary aquifers in Antelope Valley are defined as those parts of the aquifers corresponding to the perforated intervals of wells listed in the California Department of Public Health database. Public-supply wells in Antelope Valley are completed to depths between 360 and 700 feet (110 to 213 meters), consist of solid casing from the land surface to a depth of 180 to 350 feet (55 to 107 meters), and are screened or perforated below the solid casing. Recharge to the groundwater system is primarily runoff from the surrounding mountains, and by direct infiltration of irrigation and sewer and septic

Environmental radioactivity in the Faroes in 1980

International Nuclear Information System (INIS)

Aarkrog, A.; Lippert, J.; Dahlgaard, H.

1981-07-01

Measurements of fallout radioactivity in the Faroes in 1980 are presented. Strontium-90 (and 137 Cs in most cases) was determined in regularly collected samples of precipitation, grass, milk, fish, sea water, bread and drinking water. In addition, analyses were made of spot samples of lamb, sea birds, potatoes, sea plants, vegetables, eggs, and human bone. Estimates are given of the mean contents of 90 Sr and 137 Cs in human diet in the Faroes in 1980. (author)

The use of 99Mo/99mTc generators in the analysis of low levels of 99Tc in environmental samples by radiochemical methods

International Nuclear Information System (INIS)

Dowdall, M.; Selnaes, Oe.G.; Lind, B.; Gwynn, J.P.

2010-01-01

The analysis of low levels of 99 Tc in environmental samples presents special challenges, particularly with respect to the selection of an appropriate and practicable chemical yield tracer. Of all the tracers available, 99m Tc eluted from 99 Mo/ 99m Tc generators appears to be the most practicable in terms of availability, ease of use and cost. These factors have led to an increase in the use of such generators for the provision of 99m Tc as yield tracer for 99 Tc. For the analysis of low levels ( 3 or kg) of 99 Tc in environmental samples, consideration must be given to the radiochemical purity of the tracer solution with respect to contamination with both 99 Tc and other radionuclides. Due to the variable nature of the extent of the interference from tracer solution to tracer solution, it is unwise to try and establish a correction factor for any single generator. The only practical solution to the problem therefore is to run a 'blank' sample with each batch of samples drawn from a single tracer solution. (LN)

The Health Valley: Global Entrepreneurial Dynamics.

Science.gov (United States)

Dubuis, Benoit

2014-12-01

In the space of a decade, the Lake Geneva region has become the Health Valley, a world-class laboratory for discovering and developing healthcare of the future. Through visionary individuals and thanks to exceptional infrastructure this region has become one of the most dynamic in the field of innovation, including leading scientific research and exceptional actors for the commercialization of academic innovation to industrial applications that will improve the lives of patients and their families. Here follows the chronicle of a spectacular expansion into the Health Valley.

Solar energy innovation and Silicon Valley

Science.gov (United States)

Kammen, Daniel M.

2015-03-01

The growth of the U. S. and global solar energy industry depends on a strong relationship between science and engineering innovation, manufacturing, and cycles of policy design and advancement. The mixture of the academic and industrial engine of innovation that is Silicon Valley, and the strong suite of environmental policies for which California is a leader work together to both drive the solar energy industry, and keep Silicon Valley competitive as China, Europe and other area of solar energy strength continue to build their clean energy sectors.

Diversification in the Supply Chain of (99)Mo Ensures a Future for (99m)Tc.

Science.gov (United States)

Cutler, Cathy S; Schwarz, Sally W

2014-07-01

The uncertain availability of (99m)Tc has become a concern for nuclear medicine departments across the globe. An issue for the United States is that currently it is dependent on a supply of (99m)Tc (from (99)Mo) that is derived solely by production outside the United States. Since the United States uses half the world's (99)Mo production, the U.S. (99)Mo supply chain would be greatly enhanced if a producer were located within the United States. The fragility of the old (99)Mo supply chain is being addressed as new facilities are constructed and new processes are developed to produce (99)Mo without highly enriched uranium. The conversion to low-enriched uranium is necessary to minimize the potential misuse of highly enriched uranium in the world for nonpeaceful means. New production facilities, new methods for the production of (99)Mo, and a new generator elution system for the supply of (99m)Tc are currently being pursued. The progress made in all these areas will be discussed, as they all highlight the need to embrace diversity to ensure that we have a robust and reliable supply of (99m)Tc in the future. © 2014 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

Fault structure and kinematics of the Long Valley Caldera region, California, revealed by high-accuracy earthquake hypocenters and focal mechanism stress inversions

Science.gov (United States)

Prejean, Stephanie; Ellsworth, William L.; Zoback, Mark; Waldhauser, Felix

2002-01-01

We have determined high-resolution hypocenters for 45,000+ earthquakes that occurred between 1980 and 2000 in the Long Valley caldera area using a double-difference earthquake location algorithm and routinely determined arrival times. The locations reveal numerous discrete fault planes in the southern caldera and adjacent Sierra Nevada block (SNB). Intracaldera faults include a series of east/west-striking right-lateral strike-slip faults beneath the caldera's south moat and a series of more northerly striking strike-slip/normal faults beneath the caldera's resurgent dome. Seismicity in the SNB south of the caldera is confined to a crustal block bounded on the west by an east-dipping oblique normal fault and on the east by the Hilton Creek fault. Two NE-striking left-lateral strike-slip faults are responsible for most seismicity within this block. To understand better the stresses driving seismicity, we performed stress inversions using focal mechanisms with 50 or more first motions. This analysis reveals that the least principal stress direction systematically rotates across the studied region, from NE to SW in the caldera's south moat to WNW-ESE in Round Valley, 25 km to the SE. Because WNW-ESE extension is characteristic of the western boundary of the Basin and Range province, caldera area stresses appear to be locally perturbed. This stress perturbation does not seem to result from magma chamber inflation but may be related to the significant (???20 km) left step in the locus of extension along the Sierra Nevada/Basin and Range province boundary. This implies that regional-scale tectonic processes are driving seismic deformation in the Long Valley caldera.

99mTc gel generators based on zirconium molybdate-99Mo: III: Influence of preparatory conditions of zirconium molybdate-99Mo gel on generator performance

International Nuclear Information System (INIS)

Saraswathy, P.; Sarkar, S.K.; Arjun, G.; Ramamoorthy, N.; Nandy, S.K.

2004-01-01

The effect of subtle variations on zirconium molybdate- 99 Mo gel preparatory conditions, such as stoichiometry of reactants, pH of gel formation, conditioning of gel granules etc., prior to elution were investigated primarily to arrive at the conditions resulting in high 99m Tc release and minimal 99 Mo breakthrough upon elution with normal saline. Zirconium molybdate- 99 Mo gels were prepared by reacting solutions of Zr and Mo in mole ratios of 0.75-1.5. Both water and normal saline were used for gel disintegration, and the release of 99m Tc and 99 Mo from gel columns into eluates was compared. Sharper elution profile of 99m Tc, but with significantly higher 99 Mo breakthrough (5-8 times), was obtained when water alone was used for disintegration and elution, in comparison to when saline was used. Gels exhibiting optimum characteristics were found to be formed at a pH of 4-5 by reacting [Zr]: [Mo] in the mole ratio of 1.25: 1 and after drying, the product was dispersed into granules by disintegration with normal saline. 99m Tc elution efficiency was found to be ∝ 75% and 99 Mo breakthrough ∝ 0.05%. The elution profile was sharp when a 6 g gel column coupled to a 2 g acidic alumina column (to trap 99 Mo) was eluted with 6-9 ml normal saline. Generators containing upto 23 GBq 99 Mo were prepared, eluted extensively without changing the alumina column and found to provide pertechnetate of good quality, commensurate with hospital radiopharmacy requirements. (orig.)

29 CFR 99.400 - Responsibilities.

Science.gov (United States)

2010-07-01

... 29 Labor 1 2010-07-01 2010-07-01 true Responsibilities. 99.400 Section 99.400 Labor Office of the... Pass-through Entities § 99.400 Responsibilities. (a) Cognizant agency for audit responsibilities... the report submission due date required by § 99.320(a). The cognizant agency for audit may grant...

Activity report 1980

International Nuclear Information System (INIS)

Drent, W.; Delande, E.

1981-07-01

The EUROCHEMIC Company's activity report for fiscal year 1980 covers the following topics: administrative and commercial matters; personnel; cleaning and decontamination works in the reprocessing plant; operation of the bituminization facility; active treatment of the spent solvent in the Eurowatt facility; operation of the waste sorting and shredding unit, preparing the plutonium contaminated solid wastes for conditioning and recovery of plutonium; radiation protection and library and documentation. (AF)

Annual report 1980

International Nuclear Information System (INIS)

1980-12-01

In this annual report a survey is given about the research programs of the named institute during 1980. The research concerns experiments with synchrotron radiation, hyperfine structure studies, experiments with the DORIS and PETRA storage rings, and experiments at the CERN accelerators. Furthermore the development of instruments in this institute is described. In addition a list of publications, contributions to conferences, and theses of this institute is given. (HSI)

Cyclotron Production of Technetium-99m

Science.gov (United States)

Gagnon, Katherine M.

Technetium-99m (99mTc) has emerged as the most widely used radionuclide in medicine and is currently obtained from a 99Mo/ 99mTc generator system. At present, there are only a handful of ageing reactors worldwide capable of producing large quantities of the parent isotope, 99Mo, and owing to the ever growing shutdown periods for maintenance and repair of these ageing reactors, the reliable supply 99mTc has been compromised in recent years. With an interest in alternative strategies for producing this key medical isotope, this thesis focuses on several technical challenges related to the direct cyclotron production of 99mTc via the 100Mo(p,2n)99mTc reaction. In addition to evaluating the 100Mo(p,2n)99mTc and 100Mo(p,x)99Mo reactions, this work presented the first experimental evaluation of the 100Mo(p,2n) 99gTc excitation function in the range of 8-18 MeV. Thick target calculations suggested that large quantities of cyclotron-produced 99mTc may be possible. For example, a 6 hr irradiation at 500 μA with an energy window of 18→10 MeV is expected to yield 1.15 TBq of 99mTc. The level of coproduced 99gTc contaminant was found to be on par with the current 99Mo/99mTc generator standard eluted with a 24 hr frequency. Highly enriched 100Mo was required as the target material for 99mTc production and a process for recycling of this expensive material is presented. An 87% recovery yield is reported, including metallic target preparation, irradiation, 99mTc extraction, molybdate isolation, and finally hydrogen reduction to the metal. Further improvements are expected with additional optimization experiments. A method for forming structurally stable metallic molybdenum targets has also been developed. These targets are capable of withstanding more than a kilowatt of beam power and the reliable production and extraction of Curie quantities of 99mTc has been demonstrated. With the end-goal of using the cyclotron-produced 99mTc clinically, the quality of the cyclotron

Comparison of 99Tcm(V)-DMSA and 99Tcm-MIBI scintigraphy in medullary thyroid carcinoma

International Nuclear Information System (INIS)

Deng Bo; Xiao Huan; Chen Xiaofeng; Chen Huaming

2004-01-01

SPECT scintigraphy is used in 62 patients with medullary thyroid carcinoma (MTC), which are divided into two groups: 32 patients by 99 Tc m (V)-DMSA and 30 patients by 99 Tc m -MIBI. The qualitative analysis and half quantitative analysis are performed to the early and delayed images. Comparing the results with two groups, there is no difference in the masculine rate of MTC primary focus, but the results of 99 Tc m (V)-DMSA scintigraphy is obviously larger than 99 Tc m -MIBI by half quantitative analysis. The results show that the 99 Tc m (V)-DMSA scintigraphy is more predominant than the 99 Tc m -(V)-DMSA scintigraphy may be superior to 99 Tc m -MIBI in MTC primary focus and metastasis focus before surging for MTC patients. (authors)

Biogeochemical studies of wintering waterfowl in the Imperial and Sacramento Valleys

Energy Technology Data Exchange (ETDEWEB)

Koranda, J.J.; Stuart, M.; Thompson, S.; Conrado, C.

1979-10-01

Trace and major elemental composition were determined in the organs of wintering waterfowl in the Imperial and Sacramento Valleys of California, and in soils, sediments, and agricultural fertilizer that constitute the various sources of elements in the waterfowl. These data provide a biogeochemical baseline for waterfowl populations wintering in an area being developed for geothermal power. This baseline in the Imperial Valley is affected by soil and sediment composition, agricultural effluents in irrigation and stream water, and spent shot deposited by hunters in waterfowl habitats. The waterfowl acquire a set of trace elements from these sources and concentrations increase in their organs over the wintering period. Nickel, arsenic, selenium, bromine, and lead are the primary elements acquired from soil sources, agricultural effluents, and spent shot in the Imperial Valley. The assessment of effects from geothermal effluents on waterfowl populations in complex because there are large influxes of materials into the Imperial Valley ecosystem that contain trace elements, i.e., irrigation water, phosphatic fertilizers, pesticides, and lead shot. Multiple sources exist for many elements prominent in the expected geothermal effluents. The relationships between the two California valleys, the Imperial and Sacramento, are apparent in the trace element concentrations in the organs of waterfowl obtained in those two valleys. Arsenic is absent in the waterfowl organs obtained in the Sacramento Valley and relatively common in the Imperial Valley waterfowl. The effect of any release of geothermal effluent in the Imperial Valley waterfowl habitats will be difficult to describe because of the complexity of the biogeochemical baseline and the multiple sources of trace and major elements in the ecosystem.

Generator of {sup 99m} Tc with MnO{sub 2} as support of {sup 99} Mo; Generador de {sup 99m} Tc con MnO{sub 2} como soporte del {sup 99}Mo

Energy Technology Data Exchange (ETDEWEB)

Granados C, F.; Serrano G, J. [Departamento de Quimica, Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

2002-07-01

The generator of {sup 99m} Tc with MnO{sub 2} as support of {sup 99} Mo was studied. By mean of static experiments the retention of {sup 99} Mo in MnO{sub 2} in function of the stirring time and of the p H value of the solution of {sup 99} Mo. It was found that the {sup 99} Mo presents 100% of retention in MnO{sub 2} in the rank of p H 3-11 and the balance was reached before of 10 minutes. In dynamic conditions the retention of {sup 99} Mo in MnO{sub 2} at p H=5 was also higher: 99.72%. The generated {sup 99m} Tc can be separated from {sup 99} Mo, adsorbed in MnO{sub 2} packed in the column, using distilled water at p H=5 or NaCl solution at 0.9%. With saline solution the elution yields were greater than 80% and only an aliquot of 5 ml was necessary for obtaining this yield. The better results were obtained when the column was packed with 1 g of MnO{sub 2}. The water and the saline solution were passed through of the column with a flux of 1.25 ml/min. (Author)

Goldstone-Apple Valley Radio Telescope System Theory of Operation

Science.gov (United States)

Stephan, George R.

1997-01-01

The purpose of this learning module is to enable learners to describe how the Goldstone-Apple Valley Radio Telescope (GAVRT) system functions in support of Apple Valley Science and Technology Center's (AVSTC) client schools' radio astronomy activities.

Summary of the engineering assessment of inactive uranium mill tailings: Monument Valley site, Monument Valley, Arizona

International Nuclear Information System (INIS)

1981-10-01

Ford, Bacon and Davis Utah Inc. has reevaluated the Monument Valley site in order to revise the March 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Monument Valley, Arizona. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposures of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 1.1 million tons of tailings at the Monument Valley site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation also are factors. The four alternative actions presented in this engineering assessment range from millsite decontamination with the addition of 3 m of stabilization cover material to removal of the tailings to remote disposal sites and decontamination of the tailings site. Cost estimates for the four options range from about $6,600,000 for stabilization in-place, to about $15,900,000 for disposal at a distance of about 15 mi. Three principal alternatives for reprocessing the Monument Valley tailings were examined: heap leaching, treatment at an existing mill; and reprocessing at a new conventional mill constructed for tailings reprocessing. The cost of the uranium recovered would be more than $500/lb of U 3 O 8 by heap leach or conventional plant processes. The spot market price for uranium was $25/lb early in 1981. Therefore, reprocessing the tailings for uranium recovery is economically unattractive

Study of the elution 99Mo-99mTc generators produced at IPEN-CNEN/SP

International Nuclear Information System (INIS)

Lopes, Paula Regina Corain; Osso Junior, Joao Alberto

2007-01-01

Over the last years 99m Tc has become a very important asset in modern nuclear medicine, due to the emission of gamma ray of optimal energy (140 keV) and a suitable half-life (6.04 h). A further attribute of 99m Tc is its formation from the decay of 99 Mo and the availability from 99 Mo- 99m Tc generator systems. The most common and practical generator types consist of a chromatographic column packed with aluminium oxide, onto which the highly purified fission product 99 Mo (imported from Canada) is adsorbed in the form of molybdate. 99m Tc is further eluted with saline solution. The objective of this work is to study the performance and the elution profile of 99m Tc from high activity generators in order to decrease molybdenum and aluminium concentration. The experiments involved the use of paper filters and Sep Pak columns and also the changing in the time interval between elutions. 99 Mo breakthrough was measured using a dose calibrator and aluminium by UV-Vis spectrophotometry. The best results were achieved using a Sep Pak column containing neutral aluminium oxide. (author)

99mTc-Tetrofosmin scintimammography in suspected breast cancer patients: comparison with 99mTc-MIBI

International Nuclear Information System (INIS)

Kim, Seong Jang; Kim, In Ju; Kim, Yong Ki; Bae, Young Tae

2000-01-01

The aim of this study was to investigate the diagnostic role of 99m Tc-Tetrofosmin in detection of breast cancer and compared with that of 99m Tc-MIBI. Forty-eight patients with a clinically palpable mass or abnormal mammographic or ultrasonographic findings had 99m Tc-MIBI and 99m Tc-Tetrofosmin scintimammographies after intravenous injection of 925 MBq of radiopharmaceuticals. The scintimammographs were correlated with histopathologic findings. Thirty-three patients were diagnosed with breast cancer and 15 patients with benign breast diseases. The numbers of true positive, true negative, false positive, and false negative cases of 99m Tc-MIBI scintimammography were 29, 10, 5, and 4 respectively. The sensitivity, specificity, positive predictive value, and negative predictive value of 99m Tc-MIBI scintimammographies were 87.8%, 66.7%, 85.3%, and 71.4% respectively. The numbers of true positive, true negative, false positive, and false negative cases of 99m Tc-Tetrofosmin were 31, 10, 5, and 2 respectively. The sensitivity, specificity, positive predictive value, negative predictive value of 99m Tc-Tetrofosmin were 93.9%, 66.7%, 86.1%, and 73.3% respectively. One patient was false negative in both 99m Tc-Tetrofosmin scintimammographies and its size was 0.5cm. 99m Tc-Tetrofosmin and 99m Tc-MIBI were non-invasive and useful in detection of breast cancer and 99m Tc-Tetrofosmin was comparable to the 99m Tc-MIBI in detection of primary breast cancer.=20

29 CFR 99.105 - Definitions.

Science.gov (United States)

2010-07-01

... 29 Labor 1 2010-07-01 2010-07-01 true Definitions. 99.105 Section 99.105 Labor Office of the Secretary of Labor AUDITS OF STATES, LOCAL GOVERNMENTS, AND NON-PROFIT ORGANIZATIONS General § 99.105 Definitions. Audit finding means deficiencies which the auditor is required by § 99.510(a) to report in the...

Completion of the South Alligator Valley remediation, Northern Territory, Australia - -16198

International Nuclear Information System (INIS)

Waggitt, Peter; Fawcett, Mike

2009-01-01

13 uranium mines operated in the South Alligator Valley of Australia's Northern Territory between 1953 and 1963. At the end of operations the mines, and associated infrastructure, were simply abandoned. As this activity preceded environmental legislation by about 15 years there was neither any obligation, nor attempt, at remediation. In the 1980's it was decided that the whole area should become an extension of the adjacent World Heritage, Kakadu National Park. As a result the Commonwealth Government made an inventory of the abandoned mines and associated facilities in 1986. This established the size and scope of the liability and formed the framework for a possible future remediation project. The initial program for the reduction of physical and radiological hazards at each of the identified sites was formulated in 1989 and the works took place from 1990 to 1992. But even at this time, as throughout much of the valley's history, little attention was being paid to the long term aspirations of traditional land owners. The traditional Aboriginal owners, the Gunlom Land Trust, were granted freehold Native Title to the area in 1996. They immediately leased the land back to the Commonwealth Government so it would remain a part of Kakadu National Park, but under joint management. One condition of the lease required that all evidence of former mining activity be remediated by 2015. The consultation, and subsequent planning processes, for a final remediation program began in 1997. A plan was agreed in 2003 and, after funding was granted in 2005, works implementation commenced in 2007. An earlier paper described the planning and consultation stages, experience involving the cleaning up of remnant uranium mill tailings and other mining residues; and the successful implementation of the initial remediation works. This paper deals with the final planning and design processes to complete the remediation programme, which is due to occur in 2009. The issues of final containment

Preparation of clinical-scale 99Mo/99mTc column generator using neutron activated low specific activity 99Mo and nanocrystalline γ-Al2O3 as column matrix.

Science.gov (United States)

Chakravarty, Rubel; Ram, Ramu; Dash, Ashutosh; Pillai, M R A

2012-10-01

Preparation of clinical-scale (99)Mo/(99m)Tc generator using (n,γ) activated low specific activity (99)Mo and nanocrystalline γ-Al(2)O(3) as a high capacity sorbent matrix is attempted. Nanocrystalline γ-Al(2)O(3) was synthesized by 'solid state mechanochemical' reaction of aluminum nitrate with ammonium bicarbonate. Experimental parameters were optimized to effectively separate (99m)Tc from (99)Mo using this sorbent as the column matrix. The performance features of a 13 GBq (350 mCi) (99)Mo/(99m)Tc generator using this sorbent and (99)Mo produced by (n,γ) route having specific activity 12.9-18.5 GBq/g were evaluated for 10 days. The sorbent possessed the requisite selectivity for (99)Mo and demonstrated a maximum sorption capacity of 200 ± 5mg Mo/g, which is ~10 times higher than that of ordinary acidic alumina. The overall yield of (99m)Tc was >80%, with radionuclidic purity >99.99% and radiochemical purity >99%. The yield of (99m)Tc varied from 7.8 to 2.1 GBq in the eluate for the six days of operation of the generator. The radioactive concentration of (99m)Tc eluted was adequate for the formulation of radiopharmaceuticals. The performance of the generator remained consistent over an extended period of 10 days. The eluted (99m)Tc was suitable for the formulation of (99m)Tc-DMSA and (99m)Tc-EC resulting in high radiolabeling yields (>98%). The effectiveness of γ-Al(2)O(3) as a new generation sorbent in the development of clinically useful (99)Mo/(99m)Tc generator using low specific activity (99)Mo and yielding (99m)Tc with adequate radioactive concentration and high purity suitable for formulation of radiopharmaceuticals is demonstrated. Copyright © 2012 Elsevier Inc. All rights reserved.

Topographic evolution of Yosemite Valley from Low Temperature Thermochronology

Science.gov (United States)

Tripathy-Lang, A.; Shuster, D. L.; Cuffey, K. M.; Fox, M.

2014-12-01

In this contribution, we interrogate the timing of km-scale topography development in the region around Yosemite Valley, California. Our goal is to determine when this spectacular glacial valley was carved, and how this might help address controversy surrounding the topographic evolution of the Sierra Nevada. At the scale of the range, two rival hypotheses are each supported by different datasets. Low-temperature thermochronology supports the idea that the range has been high-standing since the Cretaceous, whereas geomorphic evidence suggests that much of the elevation of the Sierra Nevada was attained during the Pliocene. Recent work by McPhillips and Brandon (2012) suggests instead that both ideas are valid, with the range losing much elevation during the Cenozoic, but regaining it during Miocene surface uplift.At the local scale, the classic study of Matthes (1930) determined that most of Yosemite Valley was excavated by the Sherwin-age glaciation that ended ~1 Ma. The consensus view is in agreement, although some argue that nearby comparable valleys comparable were carved long ago (e.g., House et al., 1998). If the Quaternary and younger glaciations were responsible for the bulk of the valley's >1 km depth, we might expect apatite (U-Th)/He ages at the valley floor to be histories at these locations, these data constrain patterns of valley topography development through time. We also supplement these data with zircon 4He/3He thermochronometry, which is a newly developed method that provides information on continuous cooling paths through ~120-220 °C. We will present both the apatite and zircon 4He/3He data and, in conjunction with thermo-kinematic modeling, discuss the ability and limitations of these data to test models of Sierra Nevada topography development through time. Matthes (1930) USGS Professional Paper House et al. (1998) Nature McPhillips and Brandon (2012) American Journal of Science

Optimal decentralized valley-filling charging strategy for electric vehicles

International Nuclear Information System (INIS)

Zhang, Kangkang; Xu, Liangfei; Ouyang, Minggao; Wang, Hewu; Lu, Languang; Li, Jianqiu; Li, Zhe

2014-01-01

Highlights: • An implementable charging strategy is developed for electric vehicles connected to a grid. • A two-dimensional pricing scheme is proposed to coordinate charging behaviors. • The strategy effectively works in decentralized way but achieves the systematic valley filling. • The strategy allows device-level charging autonomy, and does not require a bidirectional communication/control network. • The strategy can self-correct when confronted with adverse factors. - Abstract: Uncoordinated charging load of electric vehicles (EVs) increases the peak load of the power grid, thereby increasing the cost of electricity generation. The valley-filling charging scenario offers a cheaper alternative. This study proposes a novel decentralized valley-filling charging strategy, in which a day-ahead pricing scheme is designed by solving a minimum-cost optimization problem. The pricing scheme can be broadcasted to EV owners, and the individual charging behaviors can be indirectly coordinated. EV owners respond to the pricing scheme by autonomously optimizing their individual charge patterns. This device-level response induces a valley-filling effect in the grid at the system level. The proposed strategy offers three advantages: coordination (by the valley-filling effect), practicality (no requirement for a bidirectional communication/control network between the grid and EV owners), and autonomy (user control of EV charge patterns). The proposed strategy is validated in simulations of typical scenarios in Beijing, China. According to the results, the strategy (1) effectively achieves the valley-filling charging effect at 28% less generation cost than the uncoordinated charging strategy, (2) is robust to several potential affecters of the valley-filling effect, such as (system-level) inaccurate parameter estimation and (device-level) response capability and willingness (which cause less than 2% deviation in the minimal generation cost), and (3) is compatible with

Quality control studies of {sup 99}Mo used in {sup 99}Mo/{sup 99m}Tc generators produced at IPEN/CNEN-SP, Brazil

Energy Technology Data Exchange (ETDEWEB)

Said, Daphne S.; Brambilla, Tania P.; Matsuda, Margareth M.N.; Osso Junior, Joao A., E-mail: daphnesaid@usp.br, E-mail: taniabrambilla@yahoo.com.br, E-mail: mmatsuda@ipen.br, E-mail: jaosso@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2015-07-01

{sup 99m}Tc is the most used radionuclide in nuclear medicine. In Brazil, the {sup 99}Mo/{sup 99m}Tc generators are produced exclusively by the Center of Radiopharmacy at IPEN-CNEN/SP, by importing {sup 99}Mo from different suppliers. {sup 99}Mo (t{sub 1/2} = 66 h) is a fission product of {sup 235}U, therefore, it can be accompanied by several radioisotopes that are highly prejudicial for human health, demanding a strict quality control of this product for generators safe use. The European Pharmacopoeia established some parameters and limits that evaluate the quality of the solution of sodium [{sup 99}Mo]molybdate, that is used as raw material for generator's production. The European Pharmacopoeia also recommends some analytical methods to perform these evaluations, however, it has been observed difficulties on the implementation of these methods by the generator's producers. These difficulties are probably related to the lack of practicability of the proposed methods and the extensive list of utilized reagents. In this work some procedures of the European Pharmacopoeia's quality control method for {sup 99}Mo were evaluated. Different types of solid phase exchanger cartridges were tested for retention of {sup 99}Mo in 3 different conditions. Cartridges that presented percentages of retention higher than 90% were also tested for separation of {sup 99}Mo from possible contaminants (Ru e Te). The results shown that solid phase exchanger cartridges that presented percentages of retention of Mo higher than 90% also presented significant percentages of retention of Ru and Te. An alternative method for separation of {sup 99}Mo from {sup 131}I (other contaminant) are also proposed. (author)

Valley-controlled propagation of pseudospin states in bulk metacrystal waveguides

Science.gov (United States)

Chen, Xiao-Dong; Deng, Wei-Min; Lu, Jin-Cheng; Dong, Jian-Wen

2018-05-01

Light manipulations such as spin-direction locking propagation, robust transport, quantum teleportation, and reconfigurable electromagnetic pathways have been investigated at the boundaries of photonic systems. Recently by breaking Dirac cones in time-reversal-invariant photonic crystals, valley-pseudospin coupled edge states have been employed to realize selective propagation of light. Here, we realize the controllable propagation of pseudospin states in three-dimensional bulk metacrystal waveguides by valley degree of freedom. Reconfigurable photonic valley Hall effect is achieved for frequency-direction locking propagation in such a way that the propagation path can be tunable precisely by scanning the working frequency. A complete transition diagram is illustrated on the valley-dependent pseudospin states of Dirac-cone-absent photonic bands. A photonic blocker is proposed by cascading two inversion asymmetric metacrystal waveguides in which pseudospin-direction locking propagation exists. In addition, valley-dependent pseudospin bands are also discussed in a realistic metamaterials sample. These results show an alternative way toward molding the pseudospin flow in photonic systems.

Valley-symmetric quasi-1D transport in ballistic graphene

Science.gov (United States)

Lee, Hu-Jong

We present our recent studies on gate-defined valley-symmetric one-dimensional (1D) carrier guiding in ballistic monolayer graphene and valley-symmetry-protected topological 1D transport in ballistic bilayer graphene. Successful carrier guiding was realized in ballistic monolayer graphene even in the absence of a band gap by inducing a high distinction ( more than two orders of magnitude) in the carrier density between the region of a quasi-1D channel and the rest of the top-gated regions. Conductance of a channel shows quantized values in units of 4e2/ h, suggesting that the valley symmetry is preserved. For the latter, the topological 1D conduction was realized between two closely arranged insulating regions with inverted band gaps, induced under a pair of split dual gating with polarities opposite to each other. The maximum conductance along the boundary channel showed 4e2/ h, again with the preserved valley symmetry. The 1D topological carrier guiding demonstrated in this study affords a promising route to robust valleytronic applications and sophisticated valley-associated functionalities based on 2D materials. This work was funded by the National Research Foundation of Korea.

Polyfluoroalkyl substance exposure in the Mid-Ohio River Valley, 1991–2012

International Nuclear Information System (INIS)

Herrick, Robert L.; Buckholz, Jeanette; Biro, Frank M.; Calafat, Antonia M.; Ye, Xiaoyun; Xie, Changchun; Pinney, Susan M.

2017-01-01

Background: Industrial discharges of perfluorooctanoic acid (PFOA) to the Ohio River, contaminating water systems near Parkersburg, WV, were previously associated with nearby residents' serum PFOA concentrations above US general population medians. Ohio River PFOA concentrations downstream are elevated, suggesting Mid-Ohio River Valley residents are exposed through drinking water. Objectives: Quantify PFOA and 10 other per- and polyfluoroalkyl substances (PFAS) in Mid-Ohio River Valley resident sera collected between 1991 and 2013 and determine whether the Ohio River and Ohio River Aquifer are exposure sources. Methods: We measured eleven PFAS in 1608 sera from 931 participants. Serum PFOA concentration and water source associations were assessed using linear mixed-effects models. We estimated between-sample serum PFOA using one-compartment pharmacokinetics for participants with multiple samples. Results: In serum samples collected as early as 1991, PFOA (median = 7.6 ng/mL) was detected in 99.9% of sera; 47% had concentrations greater than US population 95th percentiles. Five other PFAS were detected in greater than 82% of samples; median other PFAS concentrations were similar to the US general population. Serum PFOA was significantly associated with water source, sampling year, age at sampling, tap water consumption, pregnancy, gravidity and breastfeeding. Serum PFOA was 40–60% lower with granular activated carbon (GAC) use. Repeated measurements and pharmacokinetics suggest serum PFOA peaked 2000–2006 for participants using water without GAC treatment; where GAC was used, serum PFOA concentrations decreased from 1991 to 2012. Conclusions: Mid-Ohio River Valley residents appear to have PFOA, but not other PFAS, serum concentrations above US population levels. Drinking water from the Ohio River and Ohio River Aquifer, primarily contaminated by industrial discharges 209–666 km upstream, is likely the primary exposure source. GAC treatment of drinking

A {sup 99m}Tc Generator using PZC for (n,{gamma}) {sup 99}Mo

Energy Technology Data Exchange (ETDEWEB)

Adang, H G; Mutalib, A; Suparman, I; Hamid,; Purwadi, B; Pancoko, M; Setiowati, S; Yulianti, V; Robertus, D H [Radioisotope Production Center, National Atomic Energy Agency Kawasan PUSPIPTEK, Serpong (Indonesia)

1998-10-01

The high performance adsorbent Poly Zirconium Compound (PZC) was produced by Department of Radioisotope, Japan Atomic Energy Research Institute. This compound was developed as an adsorbent for natural Mo (n,{gamma}) {sup 99}Mo-{sup 99m}Tc Generator. In the present paper, we report the performance of the PZC for a {sup 99m}Tc Generator which was focused on the yield, on elution profile and {sup 99}Mo breakthrough. (author)

Geohydrology and Water Quality of the Valley-Fill Aquifer System in the Upper Sixmile Creek and West Branch Owego Creek Valleys in the Town of Caroline, Tompkins County, New York

Science.gov (United States)

Miller, Todd S.

2009-01-01

In 2002, the U.S. Geological Survey, in cooperation with the Town of Caroline and Tompkins County Planning Department, began a study of the valley-fill aquifer system in upper Sixmile Creek and headwaters of West Branch Owego Creek valleys in the Town of Caroline, NY. The purpose of the study is to provide geohydrologic data to county and town planners as they develop a strategy to manage and protect their water resources. The first aquifer reach investigated in this series is in the Town of Caroline and includes the upper Sixmile Creek valley and part of West Branch Owego Creek valley. The portions of the valley-fill aquifer system that are comprised of saturated coarse-grained sediments including medium to coarse sand and sandy gravel form the major aquifers. Confined sand and gravel units form the major aquifers in the western and central portions of the upper Sixmile Creek valley, and an unconfined sand and gravel unit forms the major aquifer in the eastern portion of the upper Sixmile Creek valley and in the headwaters of the West Branch Owego Creek valley. The valley-fill deposits are thinnest near the edges of the valley where they pinch out along the till-mantled bedrock valley walls. The thickness of the valley fill in the deepest part of the valley, at the western end of the study area, is about 100 feet (ft); the thickness is greater than 165 ft on top of the Valley Heads Moraine in the central part of the valley. An estimated 750 people live over and rely on groundwater from the valley-fill aquifers in upper Sixmile Creek and West Branch Owego Creek valleys. Most groundwater withdrawn from the valley-fill aquifers is pumped from wells with open-ended 6-inch diameter casings; the remaining withdrawals are from shallow dug wells or cisterns that collect groundwater that discharges to springs (especially in the Brooktondale area). The valley-fill aquifers are the sources of water for about 200 households, several apartment complexes, two mobile home parks

Targeting osteomyelitis with complete [99mTc]besilesomab and fragmented [99mTc]sulesomab antibodies: kinetic evaluations

International Nuclear Information System (INIS)

GRATZ, Stefan; KEMKE, Bendix; KEIZE, Patrik; KAMPEN, Wim U.; LUSTER, Markus; HÖFFKEN, Helmut

2016-01-01

The aim of this retrospective study was to compare the targeting of “pure” osteomyelitis (i.e., without surrounding soft tissue infection) by directly 99mTc-labelled complete immunoglobulin G (IgG) monoclonal antibody (MAb) ([99mTc]besilesomab) and by directly 99mTc-labelled fragment antigen-binding (FAb) MAb ([99mTc]sulesomab) in relation to their kinetic fate. A total of 73 patients with “pure” osteomyelitis were examined with [99mTc]besilesomab, (Scintimun®, IBA/CIS bio international, Saclay, France; N.=38) and [99mTc]sulesomab (LeukoScan®, Immunomedics Inc., Morris Plains, NJ, USA; N.=35). Kinetic data were deduced from whole-body and single-photon emission computed tomographic scans, performed 10 minutes to 24 hour p.i. (region-of-interest technique [ROI]). In targeting “pure” osteomyelitis, sensitivities at 1-4 hours were found to be higher for [99mTc]sulesomab (44% and 80% for [99mTc]besilesomab and [99mTc]sulesomab, respectively) but at significantly lower target/background (T/B) ratios than with [99mTc]besilesomab (1.8±0.3 versus 1.4±0.5 for [99mTc]besilesomab and [99mTc]sulesomab respectively; P<0.01). With [99mTc]besilesomab, there was a continuous osteomyelitis uptake over 24 hours, whereas with [99mTc]sulesomab, the maximal uptake occurred mostly within 1-4 hours, with subsequent clearance being slower for antigen-bound activity than for nonspecific background. Hence, diagnosis was possible mostly after 4h with [99mTc]sulesomab but often not before 24 hours with [99mTc]besilesomab, the later increasing significantly (P<0.01) in sensitivity (87% and 84% for [99mTc]besilesomab and [99mTc]sulesomab, respectively). These results show that the higher sensitivity of [99mTc]sulesomab in osteomyelitis targeting at earlier p.i. times does not rely on an increased antibody uptake but on a more rapid clearance of nonspecific background activity due to faster metabolism and excretion. Intact [99mTc]besilesomab show a slow, continuous uptake

Valley-dependent spin-orbit torques in two-dimensional hexagonal crystals

KAUST Repository

Li, Hang; Wang, Xuhui; Manchon, Aurelien

2016-01-01

We study spin-orbit torques in two-dimensional hexagonal crystals such as graphene, silicene, germanene, and stanene. The torque possesses two components, a fieldlike term due to inverse spin galvanic effect and an antidamping torque originating from Berry curvature in mixed spin-k space. In the presence of staggered potential and exchange field, the valley degeneracy can be lifted and we obtain a valley-dependent Berry curvature, leading to a tunable antidamping torque by controlling the valley degree of freedom. The valley imbalance can be as high as 100% by tuning the bias voltage or magnetization angle. These findings open new venues for the development of current-driven spin-orbit torques by structural design.

Valley-dependent spin-orbit torques in two-dimensional hexagonal crystals

KAUST Repository

Li, Hang

2016-01-11

We study spin-orbit torques in two-dimensional hexagonal crystals such as graphene, silicene, germanene, and stanene. The torque possesses two components, a fieldlike term due to inverse spin galvanic effect and an antidamping torque originating from Berry curvature in mixed spin-k space. In the presence of staggered potential and exchange field, the valley degeneracy can be lifted and we obtain a valley-dependent Berry curvature, leading to a tunable antidamping torque by controlling the valley degree of freedom. The valley imbalance can be as high as 100% by tuning the bias voltage or magnetization angle. These findings open new venues for the development of current-driven spin-orbit torques by structural design.

Archive of Census Related Products (ACRP): 1980 SAS Transport Files

Data.gov (United States)

National Aeronautics and Space Administration — The 1980 SAS Transport Files portion of the Archive of Census Related Products (ACRP) contains housing and population demographics from the 1980 Summary Tape File...

Progress report, 1980

International Nuclear Information System (INIS)

1980-01-01

The operation and development of facilities in the Foster Radiation Laboratory and the research carried out from November 1979 to October 1980 are summarized. The upgrading process for the synchrocyclotron is continuing. The main research activities are the studies of nuclear properties far from beta stability, complex nuclear reactions, the nuclear fission mechanism, and positron emission tomography. A mini-cyclotron is being installed at the Montreal Neurological Institute. Lists of personnel and publications are included

Physics research 1980

International Nuclear Information System (INIS)

1980-01-01

Research programmes at Oxford University are given for the year 1980 of the Clarendon Laboratory, Nuclear Physics Laboratory, Theoretical Physics Department and the Atmospheric Physics Department, together with provisional research programmes in Astrophysics, Metallurgy and the Science of Materials, and Archaeology and the History of Art. Items of interest to physicists are also included from Engineering Science, Geology and Mineralogy, Laboratory of Molecular Biophysics, Physical Chemistry Laboratory and the Chemical Crystallography Laboratory. (U.K.)

Annual Report 1980

International Nuclear Information System (INIS)

1981-01-01

The activities of the laboratory during 1980 are presented in a series of reports. Research has been performed with the tandem accelerator into nuclear structure, heavy-ion reactions and the systematics of transient fields and with the 3MV accelerator into capture reactions and precision calibration of gamma-ray energies. Further details are given of advances in thermal neutron capture, shell-model calculations, statistical methods, ultra sensitive mass spectrometry and radionuclides in medicine. (C.F.)

Annual report 1980

International Nuclear Information System (INIS)

The activities of the Nuclear Sciences Institute are reviewed for the year 1980 in the following fields of interest: the Grenoble cyclotron and the construction of the post-accelerator, numerical calculus, data handling, experimental methods, then in experimental physics: nuclear spectroscopy, giant resonances, reaction processes, weak interactions, intermediate energy experiments; in theoretical physics: nuclear structure, nuclear reactions, three-body problem, hypernuclear spectroscopy, various activities as medical applications and archeometry are reviewed [fr

Method of producing molybdenum-99

Science.gov (United States)

Pitcher, Eric John

2013-05-28

Method of producing molybdenum-99, comprising accelerating ions by means of an accelerator; directing the ions onto a metal target so as to generate neutrons having an energy of greater than 10 MeV; directing the neutrons through a converter material comprising techentium-99 to produce a mixture comprising molybdenum-99; and, chemically extracting the molybdenum-99 from the mixture.

West Valley Demonstration Project, West Valley, New York: Annual report

International Nuclear Information System (INIS)

1989-01-01

Under the West Valley Demonstration Project Act, Public Law 96-368, liquid high-level radioactive waste stored at the Western New York Nuclear Services Center, West Valley, New York, that resulted from spent nuclear fuel reprocessing operations conducted between 1966 and 1972, is to be solidified in borosilicate glass and transported to a federal repository for geologic disposal. A major milestone was reached in May 1988 when the Project began reducing the volume of the liquid high-level waste. By the end of 1988, approximately 15 percent of the initial inventory had been processed into two waste streams. The decontaminated low-level liquid waste is being solidified in cement. The high-level waste stream is being stored in an underground tank pending its incorporation into borosilicate glass. Four tests of the waste glass melter system were completed. These tests confirmed equipment operability, control system reliability, and provided samples of waste glass for durability testing. In mid-1988, the Department validated an integrated cost and schedule plan for activities required to complete the production of the waste borosilicate glass. Design of the radioactive Vitrification Facility continued

99mTc-MIBI, 99mTc-tetrofosmin and 99mTc-Q12 in vitro and in vivo

International Nuclear Information System (INIS)

Bernard, Bert F.; Krenning, Eric P.; Breeman, Wout A. P.; Ensing, Geert; Benjamins, Harry; Bakker, Willem H.; Visser, Theo J.; Jong, Marion de

1998-01-01

The aim of this study was to compare uptake of 99m Tc-MIBI, 99m Tc-tetrofosmin and 99m Tc-Q12 in vitro and biodistribution in vivo in rats. In vitro, uptake decreased in the order MIBI→tetrofosmin→Q12. Uptake of MIBI and tetrofosmin, but not of Q12, in cultured tumor cells was dependent on the plasma membrane and mitochondrial potential. In vivo, heart uptake of all three compounds was high and stable. Tumor uptake decreased in the order MIBI→Q12→tetrofosmin and the tumor/blood ratio in the order MIBI→tetrofosmin→Q12

Ole Bjørn Kraft 1893-1980

DEFF Research Database (Denmark)

Skov, Christian Houlberg

2010-01-01

Ole Bjørn Kraft (1893-1980) var en central konservativ politiker i årene før og efter anden verdenskrig. Han markerede sig som udpræget idépolitiker og opnåede ad flere omgange at blive minister.......Ole Bjørn Kraft (1893-1980) var en central konservativ politiker i årene før og efter anden verdenskrig. Han markerede sig som udpræget idépolitiker og opnåede ad flere omgange at blive minister....

Greenhouse effect of trace gases, 1970-1980

Science.gov (United States)

Lacis, A.; Hansen, J.; Lee, P.; Lebedeff, S.; Mitchell, T.

1981-01-01

Increased abundances were measured for several trace atmospheric gases in the decade 1970-1980. The equilibrium greenhouse warming for the measured increments of CH4, chlorofluorocarbons and N2O is between 50% and 100% of the equilibrium warming for the measured increase of atmospheric CO2 during the same 10 years. The combined warming of CO2 and trace gases should exceed natural global temperature variability in the 1980's and cause the global mean temperature to rise above the maximum of the late 1930's.

Comparison of relative renal function measured with either 99m Tc-DTPA or 99m Tc-EC dynamic scintigraphies with that measured with 99m Tc-DMSA static scintigraphy

Energy Technology Data Exchange (ETDEWEB)

Domingues, F.C.; Fujikawa, G.Y.; Decker, H.; Alonso, G.; Pereira, J.C.; Duarte, P.S. [Centro de Diagnostico Fleury, Sao Paulo, SP (Brazil). Secao de Medicina Nuclear; Sao Paulo Univ. (USP), SP (Brazil). Escola de Saude Publica. Dept. de Epidemiologia]. E-mail: paulo.duarte@fleury.com.br

2006-07-15

Objective: The aim of this study was to compare the renal function measured with either {sup 99m}Tc-DTPA or {sup 99m}Tc-EC dynamic scintigraphies with that measured using {sup 99m}Tc-DMSA static scintigraphy. Methods: the values of relative renal function measured in 111 renal dynamic scintigraphies performed either with {sup 99m}Tc-DTPA (55 studies) or with {sup 99m}Tc-EC (56 studies) were compared with the relative function measured using {sup 99m}Tc-DMSA static scintigraphy performed within a 1-month period. The comparisons were performed using Wilcoxon signed rank test. The number of {sup 99m}Tc-DTPA and {sup 99m}Tc-EC studies that presented relative renal function different by more than 5% from that measured with {sup 99m}Tc-DMSA, using chi square test were also compared. Results: the relative renal function measured with {sup 99m}Tc-EC is not statistically different from that measured with {sup 99m}Tc-DMSA (p = 0.97). The relative renal function measured with {sup 99m}Tc-DTPA was statistically different from that measured using {sup 99m}Tc-DMSA, but with a borderline statistical significance (p = 0.05). The number of studies with relative renal function different by more than 5% from that measured with {sup 99m}Tc-DMSA is higher for the {sup 99m}Tc-DTPA scintigraphy (p 0.04) than for {sup 99m}Tc-EC. Conclusion: the relative renal function measured with {sup 99m}Tc-EC dynamic scintigraphy is comparable with that measured with {sup 99m}Tc-DMSA static scintigraphy, while the relative renal function measured with {sup 99m}Tc-DTPA dynamic scintigraphy presents a significant statistical difference from that measured with {sup 99m}Tc-DMSA static scintigraphy. (author)

Comparison of relative renal function measured with either 99m Tc-DTPA or 99m Tc-EC dynamic scintigraphies with that measured with 99m Tc-DMSA static scintigraphy

International Nuclear Information System (INIS)

Domingues, F.C.; Fujikawa, G.Y.; Decker, H.; Alonso, G.; Pereira, J.C.; Duarte, P.S.; Sao Paulo Univ.

2006-01-01

Objective: The aim of this study was to compare the renal function measured with either 99m Tc-DTPA or 99m Tc-EC dynamic scintigraphies with that measured using 99m Tc-DMSA static scintigraphy. Methods: the values of relative renal function measured in 111 renal dynamic scintigraphies performed either with 99m Tc-DTPA (55 studies) or with 99m Tc-EC (56 studies) were compared with the relative function measured using 99m Tc-DMSA static scintigraphy performed within a 1-month period. The comparisons were performed using Wilcoxon signed rank test. The number of 99m Tc-DTPA and 99m Tc-EC studies that presented relative renal function different by more than 5% from that measured with 99m Tc-DMSA, using chi square test were also compared. Results: the relative renal function measured with 99m Tc-EC is not statistically different from that measured with 99m Tc-DMSA (p = 0.97). The relative renal function measured with 99m Tc-DTPA was statistically different from that measured using 99m Tc-DMSA, but with a borderline statistical significance (p = 0.05). The number of studies with relative renal function different by more than 5% from that measured with 99m Tc-DMSA is higher for the 99m Tc-DTPA scintigraphy (p 0.04) than for 99m Tc-EC. Conclusion: the relative renal function measured with 99m Tc-EC dynamic scintigraphy is comparable with that measured with 99m Tc-DMSA static scintigraphy, while the relative renal function measured with 99m Tc-DTPA dynamic scintigraphy presents a significant statistical difference from that measured with 99m Tc-DMSA static scintigraphy. (author)

In-house cyclotron production of high-purity Tc-99m and Tc-99m radiopharmaceuticals.

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Martini, Petra; Boschi, Alessandra; Cicoria, Gianfranco; Zagni, Federico; Corazza, Andrea; Uccelli, Licia; Pasquali, Micòl; Pupillo, Gaia; Marengo, Mario; Loriggiola, Massimo; Skliarova, Hanna; Mou, Liliana; Cisternino, Sara; Carturan, Sara; Melendez-Alafort, Laura; Uzunov, Nikolay M; Bello, Michele; Alvarez, Carlos Rossi; Esposito, Juan; Duatti, Adriano

2018-05-30

In the last years, the technology for producing the important medical radionuclide technetium-99m by cyclotrons has become sufficiently mature to justify its introduction as an alternative source of the starting precursor [ 99m Tc][TcO 4 ] - ubiquitously employed for the production of 99m Tc-radiopharmaceuticals in hospitals. These technologies make use almost exclusively of the nuclear reaction 100 Mo(p,2n) 99m Tc that allows direct production of Tc-99m. In this study, it is conjectured that this alternative production route will not replace the current supply chain based on the distribution of 99 Mo/ 99m Tc generators, but could become a convenient emergency source of Tc-99m only for in-house hospitals equipped with a conventional, low-energy, medical cyclotron. On this ground, an outline of the essential steps that should be implemented for setting up a hospital radiopharmacy aimed at the occasional production of Tc-99m by a small cyclotron is discussed. These include (1) target production, (2) irradiation conditions, (3) separation/purification procedures, (4) terminal sterilization, (5) quality control, and (6) Mo-100 recovery. To address these issues, a comprehensive technology for cyclotron-production of Tc-99m, developed at the Legnaro National Laboratories of the Italian National Institute of Nuclear Physics (LNL-INFN), will be used as a reference example. Copyright © 2018 Elsevier Ltd. All rights reserved.

Evaluation of '99Mo presence in eluates of 99mTc used in nuclear medicine

International Nuclear Information System (INIS)

Ribeiro, Bianca da Silva

2010-01-01

Tc-99m is used for diagnostic imaging in nuclear medicine through SPECT technique. It is obtained by the elution of 99 Mo/ 99m Tc generators. During the elution process 99 Mo can be extracted becoming a radionuclidic impurity. One of the quality parameters of the eluate is the radionuclidic purity, MBT (molybdenum break through), defined as the ratio between 99 Mo and 99m Tc activities in the eluate. The North-American and European pharmacopoeias restrict the 99 Mo content, respectively, in 0.015 e 0.1% and, according to the International Atomic Energy Agency (IAEA), the activity ratio at the moment of administration of the radiopharmaceutical to the patient, should not exceed 0.015%. In Brazil, the control of such parameter is not obliged in official regulations. Thus, the objective of this work is to evaluate the occurrence of 99 Mo in 99m Tc eluates. It was initially optimized a methodology to determine the activity of 99 Mo in eluate samples. Efficiency curves were obtained for a NaI (Tl) 8'' x 4'' scintillation detector installed at the In Vivo Monitoring Laboratory (LABMIV-IRD). The methodology has been validated through the measurement of a 99 Mo standard liquid source calibrated at the National Metrology Laboratory for Ionizing Radiation (LNMRI-IRD). The samples analyzed in this work were gently supplied by 5 Nuclear Medicine Clinics located in the city of Rio de Janeiro. The activities of 99 mTc and 99 Mo in those samples have been measured respectively at the clinics and at the LABMIV. By applying a standardized methodology, the ration between the activities were calculated. The results show that 147 out of 174 samples presented 99 Mo activities above the minimum detectable activity of the technique. On the other hand, only 2 out of 147 samples surpassed the MBT limit suggested by the IAEA and have been detected in samples eluted from generators of 750 mCi. In one of the samples, eluted from a generator of 1000 mCi, the calculated MBT value was very close

A novel electrochemical technique for the production of clinical grade 99mTc using (n, γ)99Mo

International Nuclear Information System (INIS)

Chakravarty, Rubel; Dash, Ashutosh; Venkatesh, Meera

2010-01-01

Introduction: In order to meet the growing demand for 99m Tc and to reduce the reliance on fission-produced 99 Mo, an electrochemical pathway for accessing 99m Tc through the (n, γ) 99 Mo was explored as a back-up measure and to supplement 99m Tc supply for radiopharmaceuticals application. Methods: 99m Tc from an equilibrium mixture of 99 Mo/ 99m Tc was selectively deposited on a platinum cathode in an electrochemical cell by applying optimal voltage and stripped back again into the 0.9% saline solution. The radiochemical and radionuclidic purity of the product were determined using standard techniques. 99m Tc thus obtained was used for labeling standard ligands such as dimercaptosuccinic acid (DMSA) and ethylene dicysteine (EC), to ascertain the usability. Results: Selective deposition of 99m Tc on the platinum electrode was achieved at a potential of 5 V over a period of 1 h in NaOH electrobath. The overall yield of 99m Tc was >90%, with >99.99% radionuclidic purity and >99% radiochemical purity. The performance of the generator remained consistent over a period of 10 days. The compatibility of the product in the preparation of 99m Tc-labeled formulations such as 99m Tc-DMSA and 99m Tc-EC was found to be satisfactory in terms of high labeling yields (>98%). Conclusion: A novel and attractive method has been developed to obtain highly concentrated 99m Tc, without using fission-produced 99 Mo.

7 CFR 1980.445 - Periodic financial statements and audits.

Science.gov (United States)

2010-01-01

... 7 Agriculture 14 2010-01-01 2009-01-01 true Periodic financial statements and audits. 1980.445... Program § 1980.445 Periodic financial statements and audits. All borrowers will be required to submit periodic financial statements to the lender. Lenders must forward copies of the financial statements and...

Separation of sup(99m)Tc from 99MoO3

International Nuclear Information System (INIS)

Tomicic, M.

1977-07-01

At the present time sup(99m)Tc is widely used in nuclear medicine and its uses are increasing. It can be produced by various methods, and of those most frequently used today two have special features making them particularly applicable to the large-scale production of instant sup(99m)Tc - these are solvent extraction with methyl-ethyl-ketone and the sublimation methods. This report presents a bibliographic review of these methods, their main perfomance parameters, and experience obtained from the development and operation of a sublimation generator. Separation of sup(99m)Tc from irradiated MoO 3 was carried out with high yields (75-95%) after multiple repetition of the separation process with molybdenum trioxide heated for half an hour at a maximum temperature of 850-890 deg C in an air flow. The activity ratio of molybdenum in the separated sup(99m)Tc was of the order of 4 x 10 -5 . (author)

Medicinal plants of Usherai valley, Dir, NWFP, Pakistan

International Nuclear Information System (INIS)

Hazarat, A.; Shah, J.; Ahmad, S.; Nasir, M.; Jan, A.K.; Skindar

2010-01-01

This research is based on the results of an ethno-botanical research conducted in Usherai Valley. The main objective was to enlist the wealth of medicinal plants. In total 50 species, belonging to 32 families of wild herbs, shrubs and trees were found to be used as medicinal plants by the inhabitants in the valley. (author)

AIR POLLUTION FEATURES OF THE VALLEY-BASED TOWNS IN HUNGARY

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Z. UTASI

2016-03-01

Full Text Available There are 30 valley-based towns with >10,000 inhabitants in Hungary, filled by 1.023 million people i.e. 10 % of the population. Two criteria are used to define the valley-based town. They are: (i Vertical difference between the lowest point in the town and the highest one around it should be >100 m. At the same time, (ii the same difference on the opposite side should be >50 m. Air pollution data by the National Air Pollution Observation Network are used. Five contaminants were selected and analysed for 2007, 2010 and 2013. Due to a sharp reduction in the network, we could find data for a small part of the valley-based towns. Control towns with equal air-quality observations and similar cumulative number of inhabitants were also selected. The contaminants and the number of the settlements are: NO2 manual (14 valley-based vs. 2x14 control, NO2 automatic (8 vs. 8, SO2 automatic (7 vs. 2x6, PM10 automatic (8 vs. 2x7 and PM10 deposition manual (6 vs. 8. Average values, as well as high concentration episodes (>98%thresholds are equally analysed and evaluated. The main conclusion is that there are so big differences between the years both in absolute values and relative sequence of valley-based and control groups that the analysed there years is not enough to make any final conclusion. For step-over frequencies, however valley-based towns have some advantage, possibly due to the valley-hill wind system.

Annual report 1980-1981

International Nuclear Information System (INIS)

Wilson, H.W.

1982-01-01

A review of the year 1980-1981 at the Scottish Universities Research and Reactor Centre. On the reactor side the new Ortec data acquisition and analysis system plus a new high efficiency, low background Ge detector system delivered during 1980-81 greatly increased the efficiency of radioactive measurements, the new detector alone providing a tenfold decrease in data processing time. A wide range of applications of radiochemistry in geology, medicine, biology, chemical reactions, industrial applications and other fields benefited from this. Two new mass spectrometers were installed in the Isotope Geology Unit. One (a VG Isomass 54E) for solid source samples, especially samarium, rubidium and strontium and the other (VG Micromass ''Siamese'' VG903) for stable isotope geochemistry studies of carbon, oxygen and hydrogen. Former office accommodation was converted for very low level environmental measurements. The projects and analyses undertaken are listed under the sections, Reactor related activities (physics, radiochemistry, health physics and nuclear medicine, computing and engineering), Isotope geology (solid source group, potassium argon laboratory, stable isotope geochemistry laboratory, uranium series geochronology) and NERC radiocarbon laboratory. (U.K.)

Debris Flow Occurrence and Sediment Persistence, Upper Colorado River Valley, CO.

Science.gov (United States)

Grimsley, K J; Rathburn, S L; Friedman, J M; Mangano, J F

2016-07-01

Debris flow magnitudes and frequencies are compared across the Upper Colorado River valley to assess influences on debris flow occurrence and to evaluate valley geometry effects on sediment persistence. Dendrochronology, field mapping, and aerial photographic analysis are used to evaluate whether a 19th century earthen, water-conveyance ditch has altered the regime of debris flow occurrence in the Colorado River headwaters. Identifying any shifts in disturbance processes or changes in magnitudes and frequencies of occurrence is fundamental to establishing the historical range of variability (HRV) at the site. We found no substantial difference in frequency of debris flows cataloged at eleven sites of deposition between the east (8) and west (11) sides of the Colorado River valley over the last century, but four of the five largest debris flows originated on the west side of the valley in association with the earthen ditch, while the fifth is on a steep hillslope of hydrothermally altered rock on the east side. These results suggest that the ditch has altered the regime of debris flow activity in the Colorado River headwaters as compared to HRV by increasing the frequency of debris flows large enough to reach the Colorado River valley. Valley confinement is a dominant control on response to debris flows, influencing volumes of aggradation and persistence of debris flow deposits. Large, frequent debris flows, exceeding HRV, create persistent effects due to valley geometry and geomorphic setting conducive to sediment storage that are easily delineated by valley confinement ratios which are useful to land managers.

Influence of the electrolyte in the fixation of {sup 99} Mo in hydroxyapatite as matrix of the {sup 99} Mo/ {sup 99m} Tc generator; Influencia del electrolito en la fijacion de {sup 99} Mo en hidroxiapatita coma matriz del generador {sup 99} Mo/ {sup 99m} Tc

Energy Technology Data Exchange (ETDEWEB)

Vazquez G, S.; Badillo A, V.E. [UAZ, Zacatecas (Mexico); Monroy G, F. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)]. e-mail: s_vazgro@hotmail.com

2005-07-01

The more used isotope at the moment in the services of nuclear medicine in the world is the technetium-99m. The {sup 99m} Tc emitts gamma rays of 141 keV and it semi disintegration period is of six hours, given it short half life, to produce it is necessary to order generators that are systems that allow to separate periodically at the {sup 99m}Tc of the {sup 99} Mo by means of chromatographic techniques. In this work it is sought to evaluate the use of the hydroxyapatite, to separate molybdates {sup 99} MoO{sub 4}{sup 2} of pertechnetates {sup 99m}TcO{sub 4}{sup -} and to be able to determine if it is feasible their use for to build generators of {sup 99m} Tc. With this purpose preliminary tests to know the likeness of the hydroxyapatite for the molybdates in function of the pH value, in different solutions were carried out: one of NaCl 0.9%, NaCl 2% and CaCl{sub 2} 0.01 M. The obtained results in a NaCl 0.9% solution and at to 2% to different pH values of the solution, shows that the fixation of the molybdate ions (MoO{sub 4}{sup -2}) it is worthless to basic pH values of (9-11), as long as in solution of CaCI{sub 2} 0.01 M show a considerable retention of molybdate ions. (Author)

International Centre for Theoretical Physics. Scientific activities in 1980

International Nuclear Information System (INIS)

1981-09-01

The Centre's scientific programme for 1980 falling under five main fields, i.e. Physics and Energy, Physics and Technology, Physics and Frontiers of Knowledge, Applicable Mathematics and Planning Models, and Physics of the Environment and of Natural Resources, is briefly discussed. Participation in the research and training-for-research activities of the ICTP during 1980 and the stable resources for the period 1970 to 1981 are shown in tables. A detailed ''post-spectus'' of the seminars, meetings, and courses which the centre organized in 1980 is given. A list of titles of the preprints and internal reports produced during the year is also given for each area of activity

Space-age Europe, 1957-1980

Science.gov (United States)

Mcdougall, W. A.

1985-01-01

European space related research and development from the launch of Sputnik in 1957 to 1980 in discussed. The political response to Sputnik is analyzed in the context of cold war. The development of the European Space Agency is traced.

32 CFR 99.3 - General definitions.

Science.gov (United States)