WorldWideScience
1

First assessment of low- to medium-temperature geothermal reserves in 20 Mexican states; Primera estimacion de las reservas geotermicas de temperatura intermedia a baja en veinte estados de Mexico  

Energy Technology Data Exchange (ETDEWEB)

A first, partial, assessment is included of the low- to medium-temperature geothermal reserves in 20 Mexican States and their aggregate value. The assessment covers about 29.16% of the identified geothermal-surface manifestations in the public database. For reserve assessments, we use the volumetric method, supplemented with Montecarlo simulations and statistics, to quantify inherent uncertainties. Our estimations are presented on a state-by-state basis. We estimate the aggregated reserves of the 20 states as between 7.7 x 1016 and 8.6 x 1016 kJ, with 90% confidence. The most likely reservoir temperatures range between 60-180 degrees Celsius, with a mean of 111 degrees Celsius. Such massive amounts of recoverable energy-and the associated temperatures-are potentially important for the economic development of nearby localities and the nation. [Spanish] En este trabajo se hace una primera estimacion, parcial, de las reservas geotermicas de temperatura intermedia a ...

2009-07-15

2

Proposal to neutralize acid fluids from wells in the Los Humeros, Pue., geothermal field; Propuesta para la neutralizacion de fluidos acidos provenientes de pozos del campo geotermico de Los Humeros, Pue.  

Energy Technology Data Exchange (ETDEWEB)

Neutralizing an acidic fluid consists of adding a sodium hydroxide solution to neutralize the H group of acids, therefore increasing the pH. The injection of sodium hydroxide has to be continuous and at a proper depth inside the well to protect against the corrosion of casing and surface equipment. Neutralization is a common practice used in geothermal fields, such as at The Geysers in the US and Miravalles in Costa Rica-places where aggressive fluids cause problems for extracting and using geothermal fluids commercially. A zone surrounding wells H-4, H-16 and H-29 in the northern section of the Los Humeros, Pue., geothermal field, known as the Colapso Central, has shown evidence of aggressively acidic fluids. Several wells drilled in the area had to be repaired, thus plugging and isolating the deepest production zones. Well H-43 was drilled two years ago in the northern zone of the field, and even though it is not located in the aggressive-fluid zone, the well presents mineralogical ...

2009-07-15

3

VASCULARIZATION INHIBITOR  

J-STORE (Japan)

Full Text Available

2008-01-25

4

CERN se plantea adelantar asueto para reiniciar experimento en abril  

CERN Document Server

CERN se plantea adelantar asueto para reiniciar experimento en abril

2008-01-01

6

Excretion of para-aminohippurate in the isolated perfused rat kidney: net secretion and net reabsorption.  

UK PubMed Central (United Kingdom)

1. The excretion of para-aminohippurate (PAH) in the isolated perfused rat kidney was examined over a wide range of perfusate PAH concentrations (15 microM to 6 mM). PAH excretion increased steadily...Full Text Available

1988-03-01

7

Increased endothelial and vascular smooth muscle cell adhesion on nanostructured titanium and CoCrMo  

UK PubMed Central (United Kingdom)

In the body, vascular cells continuously interact with tissues that possess nanostructured surface features due to the presence of proteins (such as collagen and elastin) embedded in the vascular wall....Full Text Available

2006-03-01

8

Fabrication and in vitro deployment of a laser-activated shape memory polymer vascular stent  

UK PubMed Central (United Kingdom)

BackgroundVascular stents are small tubular scaffolds used in the treatment of arterial stenosis (narrowing of the vessel). Most vascular stents are metallic and are deployed either...Full Text Available

9

Astrocyte-Derived Vascular Endothelial Growth Factor Stabilizes Vessels in the Developing Retinal Vasculature  

UK PubMed Central (United Kingdom)

Vascular endothelial growth factor (VEGF) plays a critical role in normal development as well as retinal vasculature disease. During retinal vascularization, VEGF is most strongly expressed by not yet...Full Text Available

10

Vascular Effects of Photodynamic and Pulsed Dye Laser Therapy Protocols  

UK PubMed Central (United Kingdom)

Background and ObjectivePulsed dye laser (PDL) treatment of cutaneous vascular lesions is associated with variable and unpredictable efficacy. Thus, alternative treatment...Full Text Available

2008-11-01

11

Fractal parameters and vascular networks: facts & artifacts  

UK PubMed Central (United Kingdom)

BackgroundSeveral fractal and non-fractal parameters have been considered for the quantitative assessment of the vascular architecture, using a variety of test specimens and of computational...Full Text Available

15

Reticulate eruptions. Part 1: Vascular networks and physiology  

British Library Electronic Table of Contents (United Kingdom)

Abstract Reticulate pattern is one of the most important dermatological signs of a pathological process involving the superficial vascular networks. Vascular malformations, such as cutis marmorata congenita telangiectasia and benign forms of livedo reticularis, and sinister conditions, such as meningococcal meningitis or Sneddon's syndrome, can all present with a reticulate pattern. The clinical presentation and morphology is determined by the nature and extent of the underlying pathology and the involvement of a particular vascular network. This review has been divided into four instalments. In the present paper, we discuss the anatomy and physiology of the complex network of vascular structures that support the function of the skin and subcutis.

2011-01-01

16

Conversion of ortho-para H2O isomers in water and a jump in erythrocyte fluidity through a microcapillary at a temperature of 36.6?0.3?C  

British Library Electronic Table of Contents (United Kingdom)

A mechanism is proposed for the previously observed [1] jump in erythrocyte fluidity through a microcapillary 1.3 ?m in diameter at a temperature of 36.6?0.3?C. Our interpretation is based on the experimental evidence both for existence of ortho and para H2O isomers in water and on spin-selective interaction of proteins with para H2O isomers as hydration shells of biomolecules are being formed [2]. It is important that the formation of hydration shells of proteins and DNA in aqueous solutions is accompanied by an increase in the Brillouin shift to 0.4 cm?1 (?0.25 cm?1 in water), which points to the formation of icelike structures. We believe that the coincidence of the translational energy kT of the Brownian motion and the energy of the rotational quanta for the 313?202 transition of para ...

2009-01-01

17

Vascular ATP-sensitive potassium channels are over-expressed and partially regulated by nitric oxide in experimental septic shock  

British Library Electronic Table of Contents (United Kingdom)

Purpose To study the activation and expression of vascular (aorta and small mesenteric arteries) potassium channels during septic shock with or without modulation of the NO pathway. Methods Septic shock was induced in rats by peritonitis. Selective inhibitors of vascular KATP (PNU-37883A) or BKCa [iberiotoxin (IbTX)] channels were used to demonstrate their involvement in vascular hyporeactivity. Vascular response to phenylephrine was measured on aorta and small mesenteric arteries mounted on a wire myograph. Vascular expression of potassium channels was studied by PCR and Western blot, in the presence or absence of 1400W, an inducible NO synthase (iNOS) inhibitor. Aortic activation of the transcriptional factor nuclear factor-kappaB (NF-?B) was assessed by electrophoretic mobility shift as...

2011-01-01

18

Vascular Access Procedures (Central Catheters)  

Science.gov (United States)

... the major types of vascular access catheters: A peripherally inserted central catheter (PICC) is a long catheter that extends ... the procedure performed? A midline catheter and some peripherally inserted central catheter (PICC) lines may be inserted at your ...

19

Tumor vascular permeability factor stimulates endothelial cell growth and angiogenesis.  

UK PubMed Central (United Kingdom)

Vascular permeability factor (VPF) is an Mr 40-kD protein that has been purified from the conditioned medium of guinea pig line 10 tumor cells grown in vitro, and increases fluid permeability from blood...Full Text Available

1989-11-01

20

The association of circulating inflammatory markers with recurrent vascular events after stroke: a prospective cohort study  

UK PubMed Central (United Kingdom)

BackgroundInflammatory markers may be associated with recurrent vascular events after stroke. We aimed to: (1) determine the association between interleukin-6, C-reactive...Full Text Available

2011-01-01

21

Targeted gene transfection from microbubbles into vascular smooth muscle cells using focused, ultrasound-mediated delivery  

UK PubMed Central (United Kingdom)

We investigate a method for gene delivery to vascular smooth muscle cells using ultrasound triggered delivery of plasmid DNA from electrostatically coupled cationic microbubbles. Microbubbles...Full Text Available

2010-09-01

22

Role of Cytokinin and Auxin in Shaping Root Architecture: Regulating Vascular Differentiation, Lateral Root Initiation, Root Apical Dominance and Root Gravitropism  

UK PubMed Central (United Kingdom)

• Background and Aims Development and architecture of plant roots are regulated by phytohormones. Cytokinin (CK), synthesized in the root cap, promotes cytokinesis, vascular...Full Text Available

2006-05-01

23

Review: Interventional radiology in peripheral vascular disease  

UK PubMed Central (United Kingdom)

Peripheral vascular diseases (PVD) are referred to as diseases affecting the blood vessels other than the heart and the brain. Interventional endovascular treatment whenever feasible has become the...Full Text Available

2008-05-01

24

Retinal Fundus Image Registration via Vascular Structure Graph Matching  

UK PubMed Central (United Kingdom)

Motivated by the observation that a retinal fundus image may contain some unique geometric structures within its vascular trees which can be utilized for feature matching, in this paper, we proposed...Full Text Available

2010-01-01

25

Radiation modification of vascular prostheses  

International Nuclear Information System (INIS)

The radiation method has been employed for the modification of the surface of vascular prostheses by means of acrylamide. As a result of the treatment, the tightness of the prosthesis walls was improved as well as an increase of surface hydrophilicity. Upon autoclaving, stable binding of polyacrylamide to prostheses is achieved. (author).

26

Poikiloderma atrophicans vasculare as a pointer to reticulosis of the skin  

UK PubMed Central (United Kingdom)

A case of reticulosis of the skin (mycosis fungoides) terminating in reticulum cell sarcoma is described where the features of poikiloderma atrophicans vasculare had been present for 40 years. The...Full Text Available

1975-07-01

27

Patency rate and complications of polytetrafluoroethylene grafts compared with polyurethane grafts for hemodialysis access  

UK PubMed Central (United Kingdom)

BackgroundThe survival of hemodialysis patients requiring dialysis depends on the long-term functioning and patency of the vascular access. Prosthetic vascular grafts are inevitably...Full Text Available

2010-10-01

28

Non-Invasive Stem Cell Therapy in a Rat Model for Retinal Degeneration and Vascular Pathology  

UK PubMed Central (United Kingdom)

BackgroundRetinitis pigmentosa (RP) is characterized by progressive night blindness, visual field loss, altered vascular permeability and loss of central vision. Currently there...Full Text Available

29

Impairment and recovery of left motor function in patients with right hemiplegia.  

UK PubMed Central (United Kingdom)

OBJECTIVE: To assess the motor function of the left, supposedly unaffected, limbs of patients with an acute right vascular hemiplegia. METHODS: Fifteen patients with an acute vascular right hemiplegia...Full Text Available

1997-01-01

30

Supersymmetric para boson-fermion oscillator systems and their spectra  

Energy Technology Data Exchange (ETDEWEB)

In this paper para boson-fermion supersymmetry is exemplified in simple oscillator systems. The parasupercharge satisfies the ordinary supersymmetry algebra. The parabosonic and parafermionic oscillators do not commute and the energy spectra are non-trivial for even the one level system. The authors calculate the partition functions and compare with those for the non-supersymmetric systems.

1991-07-20

31

Silver nanoparticles inhibit VEGF-and IL-1?-induced vascular permeability via Src dependent pathway in porcine retinal endothelial cells  

UK PubMed Central (United Kingdom)

The aim of this study is to determine the effects of silver nanoparticles (Ag-NP) on vascular endothelial growth factor (VEGF)-and interleukin-1 beta (IL-1β)-induced vascular permeability, and...Full Text Available

32

Evaluation of peripheral vascular disease by intravenous digital subtraction angiography with the Fuji computed radiography (FCR) system  

Energy Technology Data Exchange (ETDEWEB)

Intravenous digital subtraction angiography using Fuji computed radiography system (FCR-DSA) was used to evaluate 57 preoperative patients with clinical manifestations of peripheral vascular disease of lower extremity. With its high contrast resolution and good special resolution, image of FCR-DSA could offer optimal information of vascular abnormality in lower extremity distal to midfoot for the diagnosis and the choice of management.

1987-03-01

33

Evaluation of peripheral vascular disease by intravenous digital subtraction angiography with the Fuji computed radiography (FCR) system  

International Nuclear Information System (INIS)

Intravenous digital subtraction angiography using Fuji computed radiography system (FCR-DSA) was used to evaluate 57 preoperative patients with clinical manifestations of peripheral vascular disease of lower extremity. With its high contrast resolution and good special resolution, image of FCR-DSA could offer optimal information of vascular abnormality in lower extremity distal to midfoot for the diagnosis and the choice of management. (orig.).

1987-01-01

34

Economic evaluation of geothermal projects; Evaluacion economica de proyectos geotermicos  

Energy Technology Data Exchange (ETDEWEB)

Fundamentals of economic evaluation of projects to produce electricity using geothermal energy are described. Steps to obtain the basic data used to calculate the present value and the internal rate of return are described. Finally, a criterion to make an economical evaluation to take the best investment selection is shown, applied to a geothermal project in the Los Azufres, field Michoacan, Mexico. [Espanol] En este articulo se describen los diferentes topicos que se desarrollan para llevar a cabo la evaluacion economica de un proyecto para generar electricidad, desde la recopilacion de datos hasta la obtencion de los indices necesarios para la toma de decisiones, y su aplicacion a un proyecto geotermoelectrico situado en el campo de Los Azufres, Michoacan, Mexico.

1995-01-01

35

Prognostic value of dynamic MRI in assessing post-traumatic femoral head vascularity  

Energy Technology Data Exchange (ETDEWEB)

The vascular status of femoral heads in the post-traumatic period of intracapsular femoral neck fracture (ICFNF) remains uncertain until the patient actually develops avascular necrosis (AVN). Several methods for predicting the viability of femoral head have been reported, that are not effective or widely used because of unreliability, potential complications, and technical difficulties. The present study involved the use of Dynamic MRI (DMRI) in assessing femoral head vascularity to predict AVN. The role of DMRI was studied prospectively in 30 patients with 31 ICFNF. Fractures were divided in to three types (Type A, B, or C) based on the femoral head vascularity shown by dynamic curve patterns on MRI evaluation. Type A was preserved vascularity, Type B was some decrease in vascularity but still viable while Type C was significantly reduced vascularity. These ...

2009-06-15

36

Un telescopio hecho de polvo lunar - Ciencia - Ciencia @ NASA  

Science.gov (United States)

13 Oct 2010 ... Cuando la resina se endureci?, Chen la coloc? en una c?mara de vac?o para depositar una delgada capa de aluminio reflector sobre la ...

37

Role of TRAIL and the pro-apoptotic Bcl-2 homolog Bim in acetaminophen-induced liver damage  

UK PubMed Central (United Kingdom)

Acetaminophen (N-acetyl-para-aminophenol (APAP), paracetamol) is a commonly used analgesic and antipyretic agent. Although considered safe at therapeutic doses, accidental or intentional...Full Text Available

2011-06-01

39

NASA - Informe De la Misi?n STS-126  

Science.gov (United States)

17 Nov 2008 ... El Analizador de Carbono Org?nico Total ser? usado para probar muestras que vendr?n del nuevo sistema de Recobre de Agua. ...

40

NASA - COLABORACI?N INNOVATIVA REVOLUCIONAR? LA SUPERCOMPUTACION ...  

Science.gov (United States)

3 Ago 2004 ... Siguiendo las recomendaciones de la OSTP, una parte del nuevo sistema estar? disponible en la base general para asegurar que toda la ...

41

I. Cyclopeptide Alkaloids; II. Phycocyanobilipeptides.  

Science.gov (United States)

Several examples of the 14-membered, para-bridged ring system of the cyclopeptide alkaloids have been synthesized via an active ester cyclization. The yield of monomeric cyclopeptide varied from 1 to 33% and was affected by the amino acid substitution pat...

1979-01-01

42

Greenversations » Invasive species  

Science.gov (United States)

(hidróxido de calcio o cal hidratada) como un plaguicida en un programa de cuarentena para controlar la especie invasora, el coquí. Hawai está preocupada de que estos...

2011-10-07

43

Greenversations » 2009 » January  

Science.gov (United States)

(hidróxido de calcio o cal hidratada) como un plaguicida en un programa de cuarentena para controlar la especie invasora, el coquí. Hawai está preocupada de que estos...

2011-10-07

44

Bait Insecticides and Hot Water Drenches Against the Little Fire Ant, Wasmannia auropunctata (Hymenoptera: Formicidae), ...  

Science.gov (United States)

... no individualmente sería un protocolo suficiente para la cuarentena contra la pequeña hormiga de fuego en plantas ... ...

45

A method for the optimal design of networks of drinking water distribution; Un metodo para el diseno optimo de redes de distribucion de agua potable  

Energy Technology Data Exchange (ETDEWEB)

A method to select, among several commercial diameter options, the most economic combination of pipeline networks is presented. These networks comply with the discharge conditions in the pipes and pressure in the knots. It is applied a static method for the hydraulics analysis of the Engineering Institute of the Universidad Nacional Autonoma de Mexico (UNAM) and an optimization technique to reduce the number of calculations. [Spanish] Se presenta un metodo para seleccionar, de entre varias opciones de diametros comerciales, la combinacion que forma la red de tuberias mas economica que satisface las condiciones de gasto en los tubos y de presion en los nudos de la misma. Para el analisis hidraulico se emplea un metodo estatico del Instituto de Ingenieria de la Universidad Nacional Autonoma de Mexico (UNAM) y se aplica una tecnica de optimacion para reducir el numero de calculos y alcanzar la solucion.

1998-12-01

46

NMR at earth's magnetic field using para-hydrogen induced polarization  

British Library Electronic Table of Contents (United Kingdom)

A method to achieve NMR of dilute samples in the earth's magnetic field by applying para-hydrogen induced polarization is presented. Maximum achievable polarization enhancements were calculated by numerically simulating the experiment and compared to the experimental results and to the thermal equilibrium in the earth's magnetic field. Simultaneous 19F and 1H NMR detection on a sub-milliliter sample of a fluorinated alkyne at millimolar concentration (1018 nuclear spins) was realized with just one single scan. A highly resolved spectrum with a signal/noise ratio higher than 50:1 was obtained without using an auxiliary magnet or any form of radio frequency shielding.

2011-01-01

47

First occurrence of Alcaeorrhynchus grandis (Dallas) (Hemiptera: Pentatomidae) preying on defoliating caterpillars of oil palm in the state of Para, Brazil  

International Nuclear Information System (INIS)

The oil palm Elaeis guineensis is usually attacked by pests, particularly, defoliating caterpillars. Between 2004 and 2006 a stinkbug predator (Asopinae) was registered preying on caterpillars of Brassolis sophorae L., Opsiphanes invirae Hubner (Lepidoptera: Nymphalidae) and Sibine spp. (Lepidoptera: Limacodidae), reducing their populations in commercial oil palm plantations in the State of Para, Brazil. Specimens of the natural enemy were collected, mounted, and identified as Alcaeorrhynchus grandis (Dallas) (Hemiptera: Pentatomidae), corresponding to the first report of the occurrence of this stinkbug attacking defoliating caterpillars of oil palm in Brazil. (author)

2004-01-01

48

Electrochemical behavior of nickel in nitric acid and its corrosion inhibition using some thiosemicarbazone derivatives  

British Library Electronic Table of Contents (United Kingdom)

The adsorption and corrosion inhibition behavior of three selected thiosemicarbazone derivatives, namely 3-pyridinecarboxaldehyde thiosemicarbazone (META), isonicotinaldehyde thiosemicarbazone (PARA) and 2-pyridinecarboxaldehyde thiosemicarbazone (ORTHO) at the nickel surface were studied electrochemically by Tafel and impedance methods and computationally by carrying out Monte Carlo searches of configurational space on nickel/thiosemicarbazone derivative system. Electrochemical measurements showed that the inhibition efficiency of these compounds increased with increase in their concentration. The recorded inhibition efficiencies of the three tested thiosemicarbazone increase in the order: META>PARA>ORTHO. Polarization studies showed that these compounds act as mixed-type inhibitors for n...

2010-01-01

49

Determination of eigenvalues of real symmetric para-p diagonal matrices  

International Nuclear Information System (INIS)

A methods is presented for an accurate numerical determination of eigenvalues of real symmetric para-p diagonal matrices. The method takes advantage of the band structure to break up the matrix into p x p blocks and performing algebraic operations including inversions on these blocks only, no matter what the size of the matrix is. The eigenvalues are determined independently one at a time. Thus any error in the determination of one eigenvalue does not affect the other eigenvalues. The method is ideally suited for the Schroedinger eigenvalue problem of the anharmonic potentials. (author).

50

[Special cases of vascular injuries by war projectiles].  

Science.gov (United States)

The author resumes what is actually known about the behaviour of war projectiles in the target (wound ballistics). This is function of their nature, their velocity, their air trajectory. The difference between lesions due to slow moving bullets and these due to projectiles with a high kinetic energy is outlined. The last ones create, through the temporary cavitation effect, lesions at distance from the residual visible tract, particularly in the vascular conduits. The therapeutic conclusions, which derive from those ballistic behaviours, are briefly described in matter of repair of vascular war injuries [Acta chir. belg., 1982, 82, 457-461]. PMID:7148288

51

The vascular pattern and viability of microvascularized rib grafts based on periosteal circulation--an experimental study  

Energy Technology Data Exchange (ETDEWEB)

Previous reports have stressed the importance of the nutrient blood supply in rib grafts transferred by microvascular anastomoses. In the present experimental study, we have demonstrated that a rib graft transferred by microvascular anastomoses based on periosteal vessels can survive; vascular clearing studies demonstrated that the vascularity of these grafts extends not only into the cortex but the medulla as well. The relative facility of harvesting these grafts (compared with those based on nutrient vessels) should make them the favored choice. Technetium bone scintigraphy proved accurate in the assessment of both vascular pattern and microanastomotic patency. Tetracycline labeling did not correlate well with the patency of a rib graft's pedicle blood supply.

1984-11-01

53

Spatiotemporal Evolution of the fMRI Response to Ultrashort Stimuli  

UK PubMed Central (United Kingdom)

The specificity of the hemodynamic response function (HRF) is determined spatially by the vascular architecture and temporally by the evolution of hemodynamic changes. The stimulus duration...Full Text Available

2011-01-26

54

Pulmonary Vasodilator Responses to Nitroprusside and Nitroglycerin in the Dog  

UK PubMed Central (United Kingdom)

The objective of this study was to determine the direct actions of nitroprusside and nitroglycerin on the pulmonary vascular bed in the intactchest dog. These widely used nitrogen oxide-containing vasodilator...Full Text Available

1981-03-01

56

Aphakic macular oedema following prosthetic lens implantation.  

UK PubMed Central (United Kingdom)

Fluorescein angiography of the iris was performed on patients with plastic lens implants with cystoid oedema of the macula, and the nature of the vascular changes was compared with controls provided...Full Text Available

1977-05-01

57

A Summary Risk Score for the Prediction of Alzheimer Disease in Elderly Persons  

UK PubMed Central (United Kingdom)

ObjectiveTo develop a simple summary risk score for the prediction of Alzheimer disease in elderly persons based on their vascular risk profiles.DesignFull Text Available

2010-07-01

58

Neuropilin-1/GIPC1 Signaling Regulates ?5?1 Integrin Traffic and Function in Endothelial Cells  

UK PubMed Central (United Kingdom)

Neuropilin 1 (Nrp1) is a coreceptor for vascular endothelial growth factor A165 (VEGF-A165, VEGF-A164 in mice) and semaphorin 3A (SEMA3A). Nevertheless, Nrp1 null embryos display vascular...Full Text Available

2009-01-01

59

Circulation, bone scans, and tetracycline labeling in microvascularized and vascular bundle implanted rib grafts  

Energy Technology Data Exchange (ETDEWEB)

The circulation in microvascularized rib grafts has been compared with that in conventional rib grafts and in those augmented by a direct vascular bundle implantation into the bone grafts. A new experimental model has been designed to correlate vascular perfusion, bone scan patterns, tetracycline labeling, and histological findings in these bone grafts. Posterior microvascularized rib grafts were found to have a circulatory pattern identical to that of the normal rib. Failed microvascularized rib grafts were revascularized more slowly than conventional rib grafts. Vascular bundles implanted into rib grafts remained patent and increased the rate of revascularization. The stripping or preservation of periosteum had no observable effects on the rate or pattern of conventional rib graft revascularization. The circulation in rib grafts was accurately reflected in technetium 99 bone scans, as was the patency of the anastomoses of ...

1984-11-01

60

Decay behaviors of H{sub 2}{sup -} anions in solid parahydrogen. Effect of nuclear spins on chemical reactions  

Energy Technology Data Exchange (ETDEWEB)

Decay processes of H{sub 2}{sup -} anions in {gamma}-rays-irradiated solid parahydrogen were studied by using ESR spectrometer. The following interesting results were obtained. First, the initial amount of ortho-H{sub 2}{sup -} anions in the {gamma}-irradiated solid parahydrogen was three times as large as those of para-H{sub 2}{sup -} anions. Second, the amount of para-H{sub 2}{sup -} anions decreases faster than that of ortho-H{sub 2}{sup -} anions upon storage of the irradiated samples at 4.2 K. Third, the decay rate of H{sub 2}{sup -} anions is accelerated by the addition of D{sub 2} molecules. Forth, H{sub 2}{sup -} anions at 2.2 K decay faster than at 4.2 K. According to the parity conservation rule in a homonuclear diatomic molecule, the energy of ortho-H{sub 2}{sup -} anions at the ground state is lower than that of para-H{sub 2}{sup -} anions, whereas that of ortho-H{sub 2} molecules is higher than that of ...

1996-11-01

61

Vascular complications following 1500 consecutive living and cadaveric donor renal transplantations: A single center study  

International Nuclear Information System (INIS)

The aim of this study was to document vascular complications that occurred following cadaveric and living donor kidney transplants in order to assess the overall incidence of these complications at our center as well as to identify possible risk factors. In a retrospective cohort study, 1500 consecutive renal transplant recipients who received a living or cadaveric donor kidney between December 1988 and July 2006 were evaluated. The study was performed at the Nemazee Hospital, Shiraz, Iran. The assessment of the anatomy and number of renal arteries as well as the incidence of vascular complications was made by color doppler ultrasonography, angiography, and/or surgical exploration. Clinically apparent vascular complications were seen in 8.86% of all study patients (n = 133) with the most frequent being hemorrhage (n = 91; 6.1%) followed by allograft renal artery stenosis (n = 26; 1.7%), renal artery thrombosis (n = 9; ...

62

Assessment of arterial tumor vascularity in small hepatocellular carcinoma. Comparison between color Doppler ultrasonography and radiographic imagings with contrast medium: dynamic CT, angiography, and CT hepatic arteriography  

Energy Technology Data Exchange (ETDEWEB)

Hepatocellular carcinoma (HCC) is characterized by tumor vascularization from the hepatic artery. The objective of our work was to compare color Doppler ultrasonography (CDU), including power Doppler ultrasonography (PDU) with radiographic imagings with contrast medium in regard to the detection of the arterial tumor vascularity of small hepatocellular carcinomas (HCC). We examined 42 small HCC lesions 2 cm or less in diameter in 37 patients for arterial tumor vascularity by conventional CDU, PDU, dynamic computed tomography (dCT), digital subtraction angiography (DSA), and CT hepatic arteriography (CTA). Color images were detected in 25 (59.5%) and 28 (66.7%) of the 42 lesions with conventional CDU and PDU, respectively, and tumor vascularity was detected in 26 (61.9%) by dCT, 23 (54.8%) by DSA, and 29 (69.0%) by CTA. Tumor vascularity could be detected in 51.9% by PDU and CTA, ...

2000-10-01

63

Using of Itaipu hydroelectric power plant-Brazil-electric power surplus for ammonia synthesis in nitrogen fertilizers production; Utilizacao da energia junto a Usina Hidreletrica de Itaipu para a sintese de amonia para fertilizantes nitrogenados  

Energy Technology Data Exchange (ETDEWEB)

Secondary energy can be described as a surplus of electrical energy in a hydropower because the lower demand of energy in some period of the day and the excess of water in the reservoir during the rainy periods. This study proposes the using of the excess of energy at Itaipu Bi nacional for electrolytically hydrogen production and ammonia for nitrogenous fertilizers. Ammonia is a raw material for nitrogenous fertilizers synthesis and produced using hydrogen and nitrogen from the atmosphere. This paper determines the minimal cost of hydrogen production and the capacity of hydrogen production, with this data and according the ammonia market for nitrogenous fertilizers in the Centre/South region was estimated the better capacity of ammonia production for one plant near Itaipu. The process of ammonia production using energy excess is the most environmental acceptable. (author)

2000-07-01

64

Quantization of the Lie algebra so(2n+1) and of the Lie superalgebra osp(1/2n) with preoscillator generators  

CERN Document Server

The Lie algebra so(2n+1) and the Lie superalgebra osp(1/2n) are quantized in terms of 3n generators, called preoscillator generators. Apart from n "Cartan" elements the preoscillator generators are deformed para-Fermi operators in the case of so(2n+1) and deformed para-Bose operators in the case of osp(1/2n). The corresponding deformed universal enveloping algebras U_q[so(2n+1)] and U_q[osp(1/2n)] are the same as those defined in terms of Chevalley operators. The name "preoscillator" is to indicate that in a certain representation these operators reduce to the known deformed Fermi and Bose operators.

1994-01-01

65

Alkylation of anisole with 1-hexene and 1-hexanol over zeolite H-beta  

British Library Electronic Table of Contents (United Kingdom)

An examination of the kinetics of the alkylation of anisole with 1-hexene and 1-hexanol to produce alkylates over zeolite H-beta is presented. Anisole alkylation is found to occur by a set of parallel reactions when hexene is used as the alkylating agent. When hexyl alcohol is the alkylating agent, the reaction follows a multi-step parallel-series mechanism to form monoalkylates and dihexylether. With 1-hexene, a group of isomeric alkylates, viz., ortho-2-hexyl anisole (2-OHA), ortho-3-hexyl anisole (3-OHA), para-2-hexyl anisole (2-PHA), and para-3-hexyl anisole (3-PHA) was obtained. With hexanol, the olefin (hexene) and dihexyl ether were obtained additionally. The influence of process parameters like temperature, catalyst quantity, and alkylating agent on reaction behavior is reported.

2011-01-01

66

Mechanical stability of the diamond-like carbon film on nitinol vascular stents under cyclic loading  

Energy Technology Data Exchange (ETDEWEB)

The mechanical stability of diamond-like carbon (DLC) films coated on nitinol vascular stents was investigated under cyclic loading condition by employing a stent crimping system. DLC films were coated on the vascular stent of a three dimensional structure by using a hybrid ion beam system with rotating jig. The cracking or delamination of the DLC coating occurred dominantly near the hinge connecting the V-shaped segments of the stent where the maximum strain was induced by a cyclic loading of contraction and extension. However the failures were significantly suppressed as the amorphous Si (a-Si) buffer layer thickness increased. Interfacial adhesion strength was estimated from the spalled crack size in the DLC coating for various values of the a-Si buffer layer thickness.

2008-12-01

67

Diesel exhaust inhalation induces heat shock protein 70 expression in vivo  

British Library Electronic Table of Contents (United Kingdom)

Exposure to urban air pollution is an independent risk factor for increased cardiovascular diseases. Heat shock protein 70 (HSP70) has been implicated in the pathogenesis of vascular dysfunction and cardiovascular diseases. This study has been designed to determine whether inhalation of urban air induces HSP70 expression in the lung and blood as well as the association of HSP70 and air pollution-induced vascular dysfunction. Apolipoprotein E (Apo-E) deficient mice were exposed to diesel exhaust (DE) either acutely (3 days, 200 or 400 g/m3 for 6 h/day) or chronically (7 weeks, 200 or 400 g/m3 for 6 h/day). HSP70 was measured in the lung using immunohistochemistry, and in the plasma by ELISA. Abdominal aorta rings were used to determine vascular functional responses. Chronic DE-exposure incr...

2011-01-01

68

Clinical Evaluation of the Zilver Vascular Stent for Symptomatic Iliac Artery Disease  

British Library Electronic Table of Contents (United Kingdom)

PurposeTo evaluate the safety and effectiveness of the Zilver vascular stent in the treatment of de novo or restenotic lesions in the external and common iliac arteries.Materials and MethodsRegardless of the results of an initial percutaneous transluminal angioplasty (PTA), 151 consecutive patients were implanted with Zilver vascular stents (Cook, Bloomington, Ind) in up to two stenotic (?10 cm) or occluded (?5 cm) atherosclerotic lesions of the external or common iliac arteries. The primary endpoint was the rate of major adverse events within 9 months after the procedure. Major adverse events were defined as death, myocardial infarction, target lesion revascularization, and limb loss. Secondary endpoints included acute procedural success, 30-day clinical success, 9-month pat...

2008-01-01

69

var gene transcription and PfEMP1 expression in the rosetting and cytoadhesive Plasmodium falciparum clone FCR3S1.2  

UK PubMed Central (United Kingdom)

BackgroundThe pathogenicity of Plasmodium falciparum is in part due to the ability of the parasitized red blood cell (pRBC) to adhere to intra-vascular host cell...Full Text Available

70

Vascular plants of the Hanford Site  

Energy Technology Data Exchange (ETDEWEB)

An updated listing of the vascular plants of the Hanford Site is provided, along with discussions of how humans may interact with local plants and have influenced the regional flora. Based on examinations of herbarium collections at the Westinghouse Hanford Company, Pacific Northwest Laboratory, Washington State University, and Brigham Young University, 590 vascular plant species have been identified on or near the Hanford Site. This is more than twice the number of species on previously published lists of Hanford Site vascular plants. A review of the plant species that are currently listed as endangered, threatened, sensitive, or otherwise of concern to the Washington State Natural Heritage Program and the Federal Fish and Wildlife Service is included. Color photographs of selected species are included to aid identification. Lists are provided of the Hanford Site plant species that could be used as food and medicinal ...

1992-07-01

71

Transport into retina measured by short vascular perfusion in the rat.  

UK PubMed Central (United Kingdom)

1. The short duration cerebrovascular perfusion method for measuring permeability of the blood-brain barrier has been adapted to measuring transport into the retina. 2. The method has been characterized...Full Text Available

1993-10-01

72

Transmural distribution of extracellular purines in isolated guinea pig heart.  

UK PubMed Central (United Kingdom)

The purine adenosine appears to be involved in regulation of coronary vascular tone. Little is known concerning the levels and distribution of adenosine and related purines in the extracellular fluid...Full Text Available

1991-01-15

73

Subcellular Localization of Expansin mRNA in Xylem Cells12  

UK PubMed Central (United Kingdom)

Terminal differentiation of many vascular cells involves cell wall changes. Cells first elongate their primary wall, then lay down a lignified secondary wall, which is often followed by digestion of...Full Text Available

2000-06-01

74

Study of Stent Deployment Mechanics Using a High-Resolution X-ray Imaging Detector  

UK PubMed Central (United Kingdom)

To treat or prevent some of the 795,000 annual strokes in the U.S., self-expanding endo-vascular stents deployed under fluoroscopic image guidance are often used. Neuro-interventionalists need...Full Text Available

2011-03-01

75

Soluble Epoxide Hydrolase as a Therapeutic Target for Cardiovascular Diseases  

UK PubMed Central (United Kingdom)

PrefaceCardiovascular effects of epoxyeicosatrienoic acids (EETs) include vasodilation, vascular smooth muscle cell anti-migratory actions, and anti-inflammatory actions. These...Full Text Available

2009-10-01

76

Scalp Angiosarcoma Remission with Bevacizumab and Radiotherapy without Surgery: A Case Report and Review of the Literature  

UK PubMed Central (United Kingdom)

Angiosarcoma (AS) is a rare and aggressive vascular neoplasm with very poor prognosis. Patients with extensive cutaneous AS who are not surgical candidates have very limited options since there is no...Full Text Available

2011-01-01

77

Role of microRNA-23b in flow-regulation of Rb phosphorylation and endothelial cell growth  

UK PubMed Central (United Kingdom)

MicroRNAs (miRs) can regulate many cellular functions, but their roles in regulating responses of vascular endothelial cells (ECs) to mechanical stimuli remain unexplored. We hypothesize that the physiological...Full Text Available

2010-02-16

78

Recent US Patterns and Predictors of Prevalent Diabetes among Acute Myocardial Infarction Patients  

UK PubMed Central (United Kingdom)

Background. Diabetes mellitus (DM) confers high vascular risk and is a growing national epidemic. We assessed clinical characteristics and prevalence of diagnosed DM among patients...Full Text Available

79

Prognostic Significance of Peritumoral Lymphatic Vessel Density and Vascular Endothelial Growth Factor Receptor 3 in Invasive Squamous Cell Cervical Cancer  

UK PubMed Central (United Kingdom)

Cervical cancer is known to metastasize primarily by the lymphatic system. Dissemination through lymphatic vessels represents an early step in regional tumor progression, and the presence of lymphatic...Full Text Available

80

Plasminogen-125I responses in dogs to a single injection of urokinase and typhoid vaccine and to vascular injury  

UK PubMed Central (United Kingdom)

In vivo plasminogen responses to various stimuli were studied. Plasminogen-125I was prepared and used first for metabolic studies of plasminogen in control dogs. The average results were:...Full Text Available

1972-06-01

81

Physiologic Responses to Infrarenal Aortic Cross-Clamping during Laparoscopic or Conventional Vascular Surgery in Experimental Animal Model: Comparative Study  

UK PubMed Central (United Kingdom)

The aim of this study was to compare the hemodynamic and ventilatory effects of prolonged infrarenal aortic cross-clamping in pigs undergoing either laparotomy or laparoscopy. 18 pigs were used for...Full Text Available

2008-01-01

82

Lower extremity vascular stenting for a post-traumatic pseudoaneurysm in a young trauma patient  

UK PubMed Central (United Kingdom)

Endovascular treatment of post-traumatic pseudoaneurysms has become a viable, less invasive option when compared to open repair. Due to the relative youth of this technology, studies have yet to be...Full Text Available

2011-04-01

83

Increased NO bioavailability in aging male rats by genistein and exercise training: using 4, 5-diaminofluorescein diacetate  

UK PubMed Central (United Kingdom)

BackgroundSeveral kinds of anti-oxidants have drawn a lot of intension for their benefits on vascular protection. In addition, it has been demonstrated that exercise training could...Full Text Available

84

Identification of two homologs of the Kaposi's sarcoma-associated herpesvirus (human herpesvirus 8) in retroperitoneal fibromatosis of different macaque species.  

UK PubMed Central (United Kingdom)

Simian retroperitoneal fibromatosis (RF) is a vascular fibroproliferative neoplasm which has many morphological and histological similarities to human Kaposi's sarcoma (KS). Like epidemic KS in AIDS...Full Text Available

1997-05-01

85

Identification of circulating neuropilin-1 and dose-dependent elevation following anti-neuropilin-1 antibody administration  

UK PubMed Central (United Kingdom)

Neuropilin-1 (NRP1) acts as a co-receptor for class 3 semaphorins and vascular endothelial growth factor and is an attractive angiogenesis target for cancer therapy. In addition to the transmembrane...Full Text Available

2009-07-01

86

Genetic and cellular evidence of vascular inflammation in neurofibromin-deficient mice and humans  

UK PubMed Central (United Kingdom)

Neurofibromatosis type 1 (NF1) results from mutations in the NF1 tumor suppressor gene, which encodes the protein neurofibromin. NF1 patients display diverse clinical manifestations,...Full Text Available

2010-03-01

87

Exploring the impact of a decision support intervention on vascular access decisions in chronic hemodialysis patients: study protocol  

UK PubMed Central (United Kingdom)

BackgroundIn patients with Stage 5 Chronic Kidney Disease who require renal replacement therapy a major decision concerns modality choice. However, many patients defer the decision...Full Text Available

88

Evaluation of Multiplexed Fluorescent Microsphere Immunoassay for Detection of Autoantibodies to Nuclear Antigens  

UK PubMed Central (United Kingdom)

Antibodies to extractable nuclear antigens (ENA) are found in a variety of collagen vascular diseases. Determining the individual specificities of these antibodies is extremely useful in establishing...Full Text Available

2004-11-01

89

Enhancing Process and Data Collection Efficiency of Peripherally Inserted Central Catheter Insertion for Justification of an Intravenous Access Program.  

Science.gov (United States)

This purpose of this paper is to describe the optimizing Peripherally Inserted Central Catheter (PICC) insertion, revising data collection strategies, estimating workloads, and calculating the financial savings generated by the vascular access nurse (VAN)...

2004-01-01

90

Effects of old age on vascular complexity and dispersion of the hepatic sinusoidal network  

UK PubMed Central (United Kingdom)

ObjectivesIn old age, there are marked changes in both the structure of the liver sinusoidal endothelial cell and liver perfusion. The objective of this study was...Full Text Available

2008-04-01

91

Dynamic NMR effects in breast cancer dynamic-contrast-enhanced MRI  

UK PubMed Central (United Kingdom)

The passage of a vascular-injected paramagnetic contrast reagent (CR) bolus through a region-of-interest affects tissue 1H2O relaxation and thus MR image intensity. For longitudinal...Full Text Available

2008-11-18

92

Divergent Regulation of Angiopoietin-1 and -2, Tie-2, and Thrombospondin-1 Expression by Estrogen in the Baboon Endometrium  

UK PubMed Central (United Kingdom)

SUMMARYEstrogen has an important role in the reconstruction of a new vascular network in the endometrium during each menstrual cycle; however, the underlying mechanisms...Full Text Available

2010-05-01

93

Comparative study of the osseointegration of dental implants after different bone augmentation techniques: vascularized femur flap, non-vascularized femur graft and mandibular bone graft  

British Library Electronic Table of Contents (United Kingdom)

Abstract Objectives: The purpose of this study was to evaluate the osseointegration of the dental implants placed into the mandible augmented with different techniques in pigs. Material and methods: Four adult domestic pigs were used. Horizontal augmentation of the mandible was performed in animals by using vascularized femur flap (VFF), non-vascularized femur graft (NVFG) and monocortical mandibular block graft (MG). After 5 months of healing 10 dental implants were placed into each augmented site. The pigs were sacrificed after 3 months of healing. Undecalcified sections were prepared for histomorphometric analysis. Results: Mean bone-implant contact (BIC) values for implants placed into MG, NVFG and VFF were 57.38 11.97%, 76.5 7.88%, 76.53 8.15%, respectively. The BIC values of NVFG and...

2011-01-01

94

Characterization of Cytokinin and Adenine Transport in Arabidopsis Cell Cultures1[OA  

UK PubMed Central (United Kingdom)

Cytokinins are distributed through the vascular system and trigger responses of target cells via receptor-mediated signal transduction. Perception and transduction of the signal can occur at the plasma...Full Text Available

2008-12-01

95

Antioxidant Treatment Alters Peripheral Vascular Dysfunction Induced by Postnatal Glucocorticoid Therapy in Rats  

UK PubMed Central (United Kingdom)

BackgroundPostnatal glucocorticoid therapy in premature infants diminishes chronic lung disease, but it also increases the risk of hypertension in adulthood. Since glucocorticoid...Full Text Available

96

A new VCAN/versican splice acceptor site mutation in a French Wagner family associated with vascular and inflammatory ocular features  

UK PubMed Central (United Kingdom)

PurposeTo detail the highly variable ocular phenotypes of a French family affected with an autosomal dominantly inherited vitreoretinopathy and to identify the disease gene.MethodsSixteen...Full Text Available

97

A Case Report of a Patient with Hereditary Hemorrhagic Telangiectasia Treated Successively with Thalidomide and Bevacizumab  

UK PubMed Central (United Kingdom)

Hereditary hemorrhagic telangiectasia is characterized by mucocutaneous and visceral telangiectasia and involves several organs with vascular malformations. It is an autosomal dominant disease and is...Full Text Available

98

USIMINAS experience on the fabrication of work cylinders for the tandem cold mill; Fabricacao de cilindros de trabalho para o laminador continuo a frio: a experiencia da USIMINAS  

Energy Technology Data Exchange (ETDEWEB)

A description is given of the principal steps involved in `USIMINAS` work roll manufacturing project for its tandem cold mill. The service performance of these rolls was found to be similar to that rolls supplied by traditional manufacturers. (author). 5 refs., 5 figs., 3 tabs.

1991-12-31

99

Steel microstructure engineering for large diameter tubes; Engenharia de microestrutura de acos para tubos de grande diametro  

Energy Technology Data Exchange (ETDEWEB)

High and ultra-high strength steels for pipelines are produced by properly handling the steel microstructure. The metallurgical principles involved in the microstructure control are presented, with emphasis on TMCP processing, that comprises conventional controlled rolling followed by accelerated cooling. (author)

2008-05-15

100

Some aspects for structure selection; Algunas consideraciones para seleccionar una estructura  

Energy Technology Data Exchange (ETDEWEB)

This paper shows some considerations about the cost of wood, steel and cement support pillars in rural power distribution systems. The life span, mechanical properties, cost estimation and general durability of each type of pillar was evaluated, aiming a better selection of the desired one. 6 figs., 8 tabs., 4 refs.

1986-12-31

101

Monitoring drinking water networks by data telemanagement; Telegestion de datos para control de redes de agua potable  

Energy Technology Data Exchange (ETDEWEB)

The WIT telemanagement system simply, reliably and efficient by makes available to us in real time processed, ordered and managed data. Such information has been used to optimise the performance of the drinking water distribution networks on a number of housing estates. This has led to major saving in consumption and on equipment maintenance, thereby improving customer service and obtaining a more rational use of piped water. (Author)

1997-04-01

102

La falta de financiacion publica hipoteca el futuro del acelerador de protones valenciano. La Universidad de Valencia tiene avanzado el diseno de este dispositivo de alta tecnologia  

CERN Multimedia

"La Universidad de Valencia tiene avanzado el diseno de un acelerador lineal de protones, cuya culminacion depende del compromiso del Consell en sufragar la plantilla que necesitaria el centro para estar operativo" (1 page).

2002-01-01

103

Folate fortification of rice by metabolic engineering  

British Library Electronic Table of Contents (United Kingdom)

Rice, the world's major staple crop, is a poor source of essential micronutrients, including folates (vitamin B9). We report folate biofortification of rice seeds achieved by overexpressing two Arabidopsis thaliana genes of the pterin and para-aminobenzoate branches of the folate biosynthetic pathway from a single locus. We obtained a maximal enhancement as high as 100 times above wild type, with 100 g of polished raw grains containing up to four times the adult daily folate requirement.

2007-01-01

104

Cyclopeptide alkaloids. Synthesis of the ring system and its ion affinity  

International Nuclear Information System (INIS)

Several examples of the 14-membered, para-bridged ring system of the cyclopeptide alkaloids have been synthesized via an active ester cyclization. The yield of monomeric cyclopeptide varied from 1 to 33% and was affected by the amino acid substitution pattern and amide conformation of the linear peptide precursors. Both the synthetic models and a naturally occurring cyclopeptide alkaloid, ceanothine B, bind monovalent (Li"+) and divalent (Ca"2"+, Mg"2"+) cations. 4 figures, 1 table.

105

Air pollution abatement 1981. Luftreinhaltung '81. Entwicklung - Stand - Tendenzen. Materialien zum Zweiten Immissionsschutzbericht der Bundesregierung an den Deutschen Bundestag nach Para. 61 Bundes-Immissionsschutzgesetz  

Energy Technology Data Exchange (ETDEWEB)

The development of emmissions, the measures planned and carried out and the present state of research in the Federal Republic of Germany into air pollution effects and abatement technology is reported. Possible starting points and solutions for air pollution abatement measures are explored within the legal framework.

1981-01-01

106

Vascular injuries in intestinal obstruction. The role of computed tomography; Complicazioni vascolari nelle occlusioni intestinali: ruolo della tomografia computerizzata  

Energy Technology Data Exchange (ETDEWEB)

The paper investigates computerized tomography capabilities in showing vascular complications secondary to intestinal obstruction and for assessing the site and cause of obstruction. [Italian] Scopo del lavoro e' lo studio dell'uso della tomografia computerizzata nel riconoscimento di complicanze vascolari secondarie ad occlusione intestinale e della presenza, della natura e della sede dell'ostacolo alla canalizzazione intestinale.

1999-09-01

107

To study the role of dynamic magnetic resonance imaging in assessing the femoral head vascularity in intracapsular femoral neck fractures  

Energy Technology Data Exchange (ETDEWEB)

Intracapsular femoral neck fractures remain unsolved fractures even after improvement in techniques of diagnosis and internal fixation. Individuals who sustain displaced femoral neck fractures are at high risk of developing avascular necrosis and non-union. Although several methods for predicting the viability of femoral head have been reported, they are not effective or widely used because of unreliability, potential complications and technical difficulties. Dynamic MRI was introduced in the recent past as a simple, non-invasive technique to predict the femoral head viability after the femoral neck fractures. In this study role of dynamic MRI was studied in 30 patients with 31 intracapsular femoral neck fractures. Fractures were divided in to three types according to dynamic curve patterns on MRI evaluation and were followed up for 6 months to 2 years to observe the final outcome. Sensitivity, Specificity and the Accuracy of dynamic MRI in predicting vascularity ...

2010-09-15

108

To study the role of dynamic magnetic resonance imaging in assessing the femoral head vascularity in intracapsular femoral neck fractures  

International Nuclear Information System (INIS)

Intracapsular femoral neck fractures remain unsolved fractures even after improvement in techniques of diagnosis and internal fixation. Individuals who sustain displaced femoral neck fractures are at high risk of developing avascular necrosis and non-union. Although several methods for predicting the viability of femoral head have been reported, they are not effective or widely used because of unreliability, potential complications and technical difficulties. Dynamic MRI was introduced in the recent past as a simple, non-invasive technique to predict the femoral head viability after the femoral neck fractures. In this study role of dynamic MRI was studied in 30 patients with 31 intracapsular femoral neck fractures. Fractures were divided in to three types according to dynamic curve patterns on MRI evaluation and were followed up for 6 months to 2 years to observe the final outcome. Sensitivity, Specificity and the Accuracy of dynamic MRI in predicting vascularity ...

2010-09-01

109

Softwood forest thinning as a biomass source for ethanol production: A feasibility study for California  

Energy Technology Data Exchange (ETDEWEB)

A plan has been put forth to strategically thin northern California forests to reduce fire danger and improve forest health. The resulting biomass residue, instead of being open burned, can be converted into ethanol that can be used as a fuel oxygenate or an octane enhancer. Economic potential for a biomass-to-ethanol facility using this softwood biomass was evaluated for two cases: Stand-alone and co-located. The co-located case refers to a specific site with an existing biomass power facility owned by Wheelabrator Environmental Systems Inc. near Martell, California. A two-stage dilute acid hydrolysis process is used for the production of ethanol from softwoods, and the residual lignin is used to generate steam and electricity. For a plant processing 800 dry tonnes per day of feedstock, the co-located case is an economically attractive concept. Total estimated capital investment is approximately $ 70 million for the co-located case. The resulting internal rate of return is about 24% ...

2000-07-01

110

Hemodynamic characteristics of early stage hepatocellular carcinoma; In vivo evaluation with vascular imagings  

Energy Technology Data Exchange (ETDEWEB)

Hemodynamic characteristics were studied by using in vivo vascular imaging techniques in 17 resected early stage hepatocellular carcinoma (e-HCC) by comparing them with 49 resected advanced HCCs (ad-HCC) less than 3 cm in diameter. In this study, e-HCC was defined as the nodule being uniformly composed of well-differentiated HCC or adenomatous hyperplastic nodule containing well-differentiated HCC foci within the nodule. In vivo vascular imaging techniques are as follows; US angiography with intraarterial CO{sub 2} microbubbles were performed to assess the tumor arterial vascularity, and CT during arterial portography (CTAP) was performed to assess the portal perfusion within the nodule. Of 17 e-HCC nodules 5 were hypervascular, 5 were isovascular, 4 were hypovascular, and 3 were vascular spot in hypovascular pattern in contrast to 49 ad-HCC nodules, 43 of which were hypervascular and 6 were ...

1992-04-01

111

Heat transfer equipment performance diagnosis of auxiliary systems in electric power stations; Diagnostico de comportamiento de equipo de transferencia de calor de sistemas auxiliares de centrales termoelectricas  

Energy Technology Data Exchange (ETDEWEB)

In this article the methodology followed to diagnose the performance of the equipment where heat is transferred from the feed water, condensate and circulation water systems in fossil power plants (FPP). The data collection is made with the unit in normal operation, using local instrumentation without taking the equipment out of service for its installation. The equipment diagnosis is made through the analysis of the collected data in actual operation and the design data; for this purpose a thermal balance of the interested systems is performed to obtain all the conditions an operation data. Later on the performance indicative parameters (PIP) of actual operation and design are calculated and compared one against the other. Such a comparison reveals the performance deterioration and the possible equipment faults. The data obtained and the supplementary information are stored in a data base whose objective is that Comision Federal de Electricidad has on hand a prompt access to them in ...

1990-12-31

112

Study for application of multi fuel technology in the Brazilian automobilistic market; Estudo para aplicacao da tecnologia multi combustivel no mercado automobilistico brasileiro  

Energy Technology Data Exchange (ETDEWEB)

The objective of this work is a study for the application of a new technology that will be used in the engine management system in the vehicle; where the final consumer can opt for the inquiry performance or seeking an economy for the fuel consumption depending on its daily use and of the prices offered in the gas stations. Flexible Fuel is a technology in development for the automobile market that mixes the use of two fuels (gasoline and ethanol) and their mixtures in the internal combustion engine. (author)

2006-07-01

113

SIRIO: Computer system for the follow up and the optimum planning of short time exploitation of a hydroelectric system; SIRIO: sistema informatico para el seguimiento y la programacion optima de la explotacion a corto plazo de un sistema hidroelectrico  

Energy Technology Data Exchange (ETDEWEB)

Sirio is a computerized application to manage the hydroelectric system in a short time. This management is implemented as a real time tool in the Control Department. SIRIO has many modules, independent and integrated to operate and perform the data acquisition, optimization, planning simulation and planning optimization. This article presents the SIRIO System and its applications to the Iberdrola system in Tajo river.

1994-12-31

114

Project scheduling with resources constraints: application in the equipment production for the oil industry; Scheduling de projetos com restricao de recursos: aplicacao na producao de equipamentos para a industria de petroleo  

Energy Technology Data Exchange (ETDEWEB)

One of the essential steps in the main scope Project Management is the Time Management made by the planning and control of the project schedule. In this work is presented the resource constrained scheduling problem beyond its mathematical formulation and a review of papers about this issue. In sequence is presented a practical example of this model considering a simplified model of an engineering project schedule of oil production equipment. The results obtained with the model application are shown and the conclusions about the work with resource constrained scheduling problems. (author)

2008-07-01

115

Methodology for fabrication of hydraulics mini turbines with composite materials; Metodologia para a fabricacao de mini turbinas hidraulicas com materiais compostos  

Energy Technology Data Exchange (ETDEWEB)

This paper presents the description of methodological procedure specially developed for manufacturing mini turbines. This procedure is used in the design of a Francis type mini turbine with 12.5 kW. The housing volute and the suction tube of this equipment are manufactured with using composed material based on glass fiber and its distributor system is manufactured with stainless steel and brass. At the end it is presented an estimate cost of design / manufacturing of such equipment and a comparison with other equipment in the market.

2009-07-01

116

Method to generate the first design of the reload pattern to be used with the Presto-B code in the simulation of the CNLV U-1 reactor; Metodo para generar el primer diseno del patron de recarga a ser utilizado con el codigo Presto-B, en la simulacion del reactor de la CNLV U-1  

Energy Technology Data Exchange (ETDEWEB)

This guide is applied for the reload pattern's formation for mirror symmetry of a core room and in accordance with the Control Cell core technique (of the english Control Cell Core - CCC) for the PRESTO-B code. (Author)

1992-08-15

117

Kevlar, the 'universal fiber'. Properties and applications in industry, sports and recreation. Kevlar - die 'Alleskoenner-Faser'. Eigenschaften und Anwendung in Industrie, Sport und Freizeit  

Energy Technology Data Exchange (ETDEWEB)

This article gives a survey of the history, properties and applications of 'Kevlar' aramide fibers. For example, the 'Kevlar' para-aramide fiber is used in compound materials in ship-, aircraft- and vehicle construction. 'Kevlar' is used as a replacement for asbestos, for example in brakes, clutches and seals or as rubber reinforcement (tyres, conveyor belts, hoses). The aramide fibers also offer manufacturers of ropes, hawsers and cables a near ideal range of properties. (MM).

1988-12-01

118

Development of a synchronous key to controlled energization of three-phase transformers; Desenvolvimento de uma chave sincrona para energizacao controlada de transformadores trifasicos  

Energy Technology Data Exchange (ETDEWEB)

This work describes the development of a synchronous key based on micro controller to the switching of three-phase power transformers, which makes possible the achievement of tests to register the inrush current, and the previous establishment of the instantaneous values of the voltage firstly applied to different phases of the energy process. This key is a value tool to the development electric power system projects and to the teaching and researching activities at the laboratory related to transitory phenomena and electric system protection.

2009-07-01

119

The diagnosis of inflammatory muscular and vascular conditions using MRT with STIR sequences  

International Nuclear Information System (INIS)

The role of MRT in the prebiopsy diagnosis of muscular and vascular inflammatory conditions was evaluated prospectively and an optimal method of examination was investigated. 92 patients with a suspected diagnosis of myositis (60 cases) or vasculitis (32 cases) were examined, in each case two extremities were studied using transverse T_1 and T_2 weighted SE sequences and double echo STIR sequences on a 0.5 Tesla (56 patients) or 1.5 Tesla magnet (36 patients; T5/S15 Gyroscan, Philips). The site of the biopsy depended on the MRT findings. In 41 patients the suspected diagnosis was confirmed histologically, in two patients an infective myositis was diagnosed on clinical grounds despite negative histology. MRT demonstrated muscle oedema in 86% of patients. There were negative findings after immuno-suppressive therapy (two patients), in focal myositis (3 out of 4 patients) and in one of 7 patients with untreated vasculitis. Amongst 49 patients in whom the suspected ...

120

Endoluminal vascular prostheses; Endoluminale Gefaessprothesen  

Energy Technology Data Exchange (ETDEWEB)

Endoluminal vascular prostheses that can be implanted by percutaneous routes represent the most recent development in vascular interventional radiology. Various commercially available types of prosthesis are presented and the construction principles and applications are described. At present secure indications for the implantation of endoluminal prostheses are limited to the elimination of aneurysms and arteriovenous fistulae of the large vessels near the trunk in sections that do not cross a joint. The wide use in peripheral occlusive diseases cannot yet be recommended because confirmed data are not available. (orig.) [German] Endoluminale Gefaessprothesen, die perkutan implantierbar sind, stellen die juengste Entwicklung in der vaskulaeren interventionellen Radiologie dar. Verschiedene kommerziell erhaeltliche Prothesentypen werden vorgestellt, ihr Konstruktionsprinzip und ihre Applikation erlaeutert. Die gesicherten Indikationen zur ...

2000-06-01

121

Supramolecular selectivity of [60]-fullerene among equivalently photoactive porphyrins  

International Nuclear Information System (INIS)

The photophysical investigation of different para-substituted tetraphenylporphyrins (TP), viz., meso-tetra(4'-hydroxyphenyl)-21H-23H-porphyrin(1),meso-tetrakis (4'-hex-5-enyloxyphenyl)-21H-23H-porphyrin(2), meso-tetrakis(4'-oct-7-enyloxyphenyl)-21H-23H-porphyrin(3) and meso-tetrakis(4'-undecyloxyphenyl)-21H-23H-porphyrin (4) revealed that except for quantum yield (#phi#) the para-substitution has little effect on any other photophysical properties like lifetime, excitation, emission wavelength, etc. The host-guest type interactions of these tetraarylporphyrins (TP 1-4), with [60]-fullerene (F) have been studied with "1H NMR and fluorescence spectrometric techniques in carbon tetrachloride medium. Fluorescence studies revealed that the Q band of the TPs was sufficiently quenched upon addition of F. All the fullerene/porphyrin systems were found to produce stable complexes with 1:1 stoichiometry. Binding constants (K) of all the ...

2010-10-01

122

Qualitative aspects in the projects that are developed in the Instituto de Investigaciones Electricas; Aspectos cualitativos en los proyectos que se desarrollan en el Instituto de Investigaciones Electricas  

Energy Technology Data Exchange (ETDEWEB)

The globalization of markets has generated more options of purchase of all type of goods and services, these options have generated opportunities and threats for all the companies and have looked for the satisfaction of the client as a strategy to remain or incursion into the global market. The Instituto de Investigaciones Electricas (IIE) is not the exception and therefore it looks for the identification of the qualitative aspects and to systematize its application in the projects that executes by means of the implantation of a system of quality assurance based on the series of ISO 9000 Standards. Some examples are described to identify the qualitative aspects of the projects that are developed in the Institute. [Spanish] La globalizacion de los mercados ha generado mas opciones de compra de todo tipo de bienes y servicios, dichas opciones han generado oportunidades y amenazas para todas las empresas y se ha buscado satisfacer al cliente como estrategia ...

1999-07-01

123

Resource Management plan for the Oak Ridge Reservation. Volume 28, Wetlands on the Oak Ridge Reservation  

Energy Technology Data Exchange (ETDEWEB)

A survey of wetlands on the Oak Ridge Reservation (ORR) was conducted in 1990. Wetlands occurring on ORR were identified using National Wetlands Inventory (NWI) maps and field surveys. More than 120 sites were visited and 90 wetlands were identified. Wetland types on ORR included emergent communities in shallow embayments on reservoirs, emergent and aquatic communities in ponds, forested wetland on low ground along major creeks, and wet meadows and marshes associated with streams and seeps. Vascular plant species occurring on sites visited were inventoried, and 57 species were added to the checklist of vascular plants on ORR. Three species listed as rare in Tennessee were discovered on ORR during the wetlands survey. The survey provided an intensive ground truth of the wetlands identified by NWI and offered an indication of wetlands that the NWI remote sensing techniques did not detect.

1991-12-01

124

Resource Management plan for the Oak Ridge Reservation  

Energy Technology Data Exchange (ETDEWEB)

A survey of wetlands on the Oak Ridge Reservation (ORR) was conducted in 1990. Wetlands occurring on ORR were identified using National Wetlands Inventory (NWI) maps and field surveys. More than 120 sites were visited and 90 wetlands were identified. Wetland types on ORR included emergent communities in shallow embayments on reservoirs, emergent and aquatic communities in ponds, forested wetland on low ground along major creeks, and wet meadows and marshes associated with streams and seeps. Vascular plant species occurring on sites visited were inventoried, and 57 species were added to the checklist of vascular plants on ORR. Three species listed as rare in Tennessee were discovered on ORR during the wetlands survey. The survey provided an intensive ground truth of the wetlands identified by NWI and offered an indication of wetlands that the NWI remote sensing techniques did not detect.

1991-12-01

125

Locally invasive lymphangiosarcoma in a young domestic shorthair  

British Library Electronic Table of Contents (United Kingdom)

A 2-year-old, female spayed, domestic shorthair cat presented to the University of Missouri-Veterinary Medical Teaching Hospital (UMC-VMTH) with an approximately 11-month history of fluid-draining pockets along her ventral thorax and axillae. The skin in these regions was erythematous, and multiple areas drained a serous to serosanguinous fluid. Fluid-filled, nodules formed along the ventrum, but these nodules disappeared as fluid drained spontaneously. Histologic assessment of skin biopsies revealed areas of vascular proliferation extending along the deep margin of the section and rare instances of invasion into the superficial dermis. These vascular channels were devoid of cells, lined by variably pleomorphic endothelial cells which had a low mitotic index. Based on the mild to moderate ...

2011-01-01

126

Excessive bleeding in the floor of the mouth after endosseus implant placement: a report of two cases  

British Library Electronic Table of Contents (United Kingdom)

Placement of dental implants in the interforaminal region of the edentulous mandible is considered a safe and routine surgical procedure. Hemorrhage in the floor of the mouth has been reported as a rare, potentially life-threatening complication related to the placement of implants in this region. In this case report the authors present an immediate and a delayed case of massive bleeding in the floor of the mouth after implant placement. This highly vascularized region is vulnerable and bleeding can be induced easily by instrumentation, causing a vascular trauma, usually by perforation of lingual periostium. In almost all cases the expanding hematoma formation starts during surgery. The effect of the vasoconstrictive agent in the local anesthesic combined with an injury of the lingual arte...

2010-01-01

127

Vascular filtration function in galactose-fed versus diabetic rats: The role of polyol pathway activity  

Energy Technology Data Exchange (ETDEWEB)

These studies were undertaken to assess the effects of increased galactose (v increased glucose) metabolism via the polyol pathway on vascular filtration function in the kidneys, eyes, nerves, and aorta. Quantitative radiolabeled tracer techniques were used to assess glomerular filtration rate (GFR) and regional tissue vascular clearance of plasma 131I-bovine serum albumin (BSA) in five groups of male Sprague-Dawley rats: nondiabetic controls, streptozotocin-diabetic rats, nondiabetic rats fed a 50% galactose diet, diabetic rats treated with sorbinil (an aldose reductase inhibitor), and galactose-fed rats treated with sorbinil. Sorbinil was added to the diet to provide a daily dose of approximately .2 mmol/kg body weight. After 2 months of diabetes or galactose ingestion, albumin clearance was increased twofold to fourfold in the eye (anterior uvea, choroid, and retina), sciatic nerve, aorta, and kidney; GFR was increased approximately twofold ...

1990-07-01

128

True aneurysm originating from the costocervical trunk: surgical excision for recurrence after successful proximal coil embolization.  

Science.gov (United States)

A rare, true aneurysm of a branch of the right subclavian artery is described. Transcatheter coil embolization of the feeder artery was successful in obliterating blood flow into the aneurysm and the mass reduced in size. However, the aneurysm reenlarged over the next week of follow-up due to development and enlargement of the collateral vascular network. Extirpation of the aneurysm was performed. Histopathological examination revealed a true aneurysm. PMID:11833847

2002-01-01

129

Transbrachial arterial digital subtraction angiography  

International Nuclear Information System (INIS)

27 cases including 7 outpatients, underwent intraarterial DSA using 4-F nylon catheter, by transbrachial arterial approach. Much of DSAs were performed in Fuji Computed Radiography (FCR), which has high spatial resolution. In all cases, image quality satisfied clinical demands. No major complication occured in this series. Transbrachial arterial digital subtraction angiography is excellent and safe method for screening of vascular disease. (author).

1985-01-01

130

Systemic combinatorial peptide selection yields a non-canonical iron-mimicry mechanism for targeting tumors in a mouse model of human glioblastoma  

UK PubMed Central (United Kingdom)

The management of CNS tumors is limited by the blood-brain barrier (BBB), a vascular interface that restricts the passage of most molecules from the blood into the brain. Here we show that phage particles...Full Text Available

2011-01-04

131

Practical approach to the loss of smell  

Energy Technology Data Exchange (ETDEWEB)

Loss of the sense of smell can be easily confirmed in any physician's office by having the patient try to identify various odors. The etiology of anosmia can be extremely varied, including nasopharyngeal disorders such as rhinitis and tumors; neurologic conditions such as head trauma, neoplasms, vascular lesions and infections of the central nervous system; viral infections; familial and congenital disorders; drugs; industrial exposure; endocrine diseases, and several other disorders. The prognosis of anosmia is guarded, and its treatment depends on the etiology.

1982-09-01

132

Natriuretic peptides in vascular physiology and pathology.  

Science.gov (United States)

Four major natriuretic peptides have been isolated: atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), C-type natriuretic peptide (CNP), and Dendroaspis-type natriuretic peptide (DNP). Natriuretic peptides play an important role in the regulation of cardiovascular homeostasis maintaining blood pressure and extracellular fluid volume. The classical endocrine effects of natriuretic peptides to modulate fluid and electrolyte balance and vascular smooth muscle tone are complemented by autocrine and paracrine actions that include regulation of coronary blood flow and, therefore, myocardial perfusion; modulation of proliferative responses during myocardial and vascular remodeling; and cytoprotective anti-ischemic effects. The actions of natriuretic peptides are mediated by the specific binding of these peptides to three cell surface receptors: type A natriuretic peptide receptor (NPR-A), type B natriuretic peptide receptor (NPR-B), ...

2008-01-01

133

Locked nucleic acid modified DNA enzymes targeting early growth response-1 inhibit human vascular smooth muscle cell growth  

UK PubMed Central (United Kingdom)

Smooth muscle cell (SMC) proliferation and migration are key processes that occur in the pathogenesis of atherosclerosis and post-angioplasty restenosis. In the present study, we designed locked nucleic...Full Text Available

2004-01-01

134

Hypoxia down-regulates sFlt-1 (sVEGFR-1) expression in human microvascular endothelial cells by a mechanism involving mRNA alternative processing  

UK PubMed Central (United Kingdom)

sFlt-1 (soluble Flt-1) potently inhibits angiogenesis by binding extracellularly to VEGF (vascular endothelial growth factor). In the present paper, we report that hypoxia down-regulates sFlt-1 expression...Full Text Available

2011-06-01

135

Distinct Roles of Nox1 and Nox4 in Basal and Angiotensin II-Stimulated Superoxide and Hydrogen Peroxide Production  

UK PubMed Central (United Kingdom)

NADPH oxidases are major sources of superoxide (O2) and hydrogen peroxide (H2O2) in vascular cells. Production of these reactive oxygen species...Full Text Available

2008-11-01

136

Correct diagnosis of vascular encasement and longitudinal extension of hilar cholangiocarcinoma by four-channel multidetector-row computed tomography  

International Nuclear Information System (INIS)

Accurate diagnosis of local invasion of hilar cholangiocarcinomas is challenging due to their small size and the anatomic complexity of the hepatic hilar region. On the other hand, the correct diagnosis of local invasion is essential for assuring the possibility of curative surgery. The purpose of this study was to evaluate the feasibility of four-channel multidetector-row computed tomography (MDCT) in the assessment of vascular and bile duct involvement, by which we could obtain useful information for the surgical management of hilar cholangiocarcinoma. The subjects were 18 patients for whom the extent of tumor invasion was surgically and pathologically confirmed. All patients underwent preoperative multiphasic CT scanning by MDCT. Arterial and portal dominant phases were acquired using a detector configuration of 1.25 mm x 4 mm, and both axial and multiplanar reconstructed images were interpreted. Longitudinal extension was evaluated up to second-order branches. ...

2009-01-01

137

Beta-estradiol attenuates hypoxic pulmonary hypertension by stabilizing the expression of p27kip1 in rats  

UK PubMed Central (United Kingdom)

BackgroundPulmonary vascular structure remodeling (PVSR) is a hallmark of pulmonary hypertension. P27kip1, one of critical cyclin-dependent kinase inhibitors, has been...Full Text Available

2010-01-01

138

An activated renin-angiotensin system maintains normal blood pressure in aryl hydrocarbon receptor heterozygous mice but not in null mice  

UK PubMed Central (United Kingdom)

It has been postulated that fetal vascular abnormalities in aryl hydrocarbon receptor null (ahr−/−) mice may alter cardiovascular homeostasis in adulthood....Full Text Available

2010-07-15

139

?2 integrins are required for skin homing of primed T cells but not for priming naive T cells  

UK PubMed Central (United Kingdom)

β2 integrins are of critical importance for leukocyte extravasation through vascular endothelia and for T cell activation. To elucidate the role of β2 integrins...Full Text Available

2002-01-15

140

?1A/B-Knockout mice explain the native ?1D-adrenoceptor's role in vasoconstriction and show that its location is independent of the other ?1-subtypes  

UK PubMed Central (United Kingdom)

Background and purpose:Theoretically, three α1-adrenoceptor subtypes can interact at the signalling level to alter vascular contraction or at the molecular level...Full Text Available

2009-12-01

141

Validation of a new software version for monitoring of the core of the Unit 2 of the Laguna Verde power plant with ARTS; Validacion de una nueva version del software para monitoreo del nucleo de la Unidad 2 de la Central Laguna Verde con ARTS  

Energy Technology Data Exchange (ETDEWEB)

In this work it is intended a methodology to validate a new version of the software used for monitoring the reactor core, which requires of the evaluation of the thermal limits settled down in the Operation Technical Specifications, for the Unit 2 of Laguna Verde with ARTS (improvements to the APRMs, Rod Block Monitor and Technical specifications). According to the proposed methodology, those are shown differences found in the thermal limits determined with the new versions and previous of the core monitoring software. Author)

2005-07-01

142

Use of sodium aluminate in waste water treatment plants: wishes of saving money and innovating; Uso del aluminato sodico en las EDAR: una propuesta para innovar y economizar costes de explotacion  

Energy Technology Data Exchange (ETDEWEB)

Most waste water treatment plants have processes to remove nutrients in order to avoid eutrophication in water receiving bodies. Regarding phosphorus removal. the most common option is chemical precipitation with ferric or aluminical precipitation with ferric or aluminium salts. We show here the successful experience carried out by the WWTP of Blanes and the company Safloc. A method ato remove phosphorus from waste water was developed by adding sodium aluminate. The use of this compound has turned out to be a sustainable way for this purpose in terms of costs, reliability and minimization of sludge production. (Author)

2006-07-01

143

Sensors to detect CO based in SnO. Sensores para detectar CO basados en SnO  

Energy Technology Data Exchange (ETDEWEB)

The development of solid state chemical sensors, and more specifically of gas sensors, is carried out with great strength in the present time since the environmental pollution and the security in work and domestic ambient are problems of great interest and social impact. The main fields of application, are: automobile, domestic sensors, control of industrial process, bio medicine, environment. These chemical sensors are experimenting a great advance because of the advantages they offer, as low cost, simple operation, possibility of measure continuous and ''In situ'' and small size, in contrast with analytical techniques that need complex instrumentation and large size equipments. In the present work, a sensor for CO detecting concentrations as low as 50 p.p.m., is studied showing great interest since this gas is highly toxic even to such a low concentration. (Author)

1993-01-01

144

Project of the new measurement system for energy invoicing - Itaipu Hydroelectric Central; Proyecto del nuevo sistema de medicion de energia para facturacion de la Central Hidroelectrica de Itaipu  

Energy Technology Data Exchange (ETDEWEB)

Itaipu Binacional has taken a decision of executing a technological updating for the energy measurement system through the substitution of the current system by other one equipped with digital devices. The main reasons for that were the following: a) The equipment in operation were of an outdated generation b) The accuracy class of the existing equipment was of 0.5%, but the tendency for invoicing measurements was to install meters with accuracy class of 0.2% in the enterprises c) The requirements of ONS/MAE, in Brazil, which establishes the minimum requisites to be attended by invoicing measurement systems.

2001-07-01

145

Preparation and dosimetry of radiotherapeutic particles for arthropaties; Preparacion y dosimetria de particulas radioterapeuticas para artropatias  

Energy Technology Data Exchange (ETDEWEB)

It was developed a new formulation of macro aggregates of Samarium 153 ({sup 153} Sm-MH) for the arthropaties treatment. The radio pharmaceutic was prepared by reaction of Samarium 153 chloride (SmCl{sub 3}) in aqueous environment with sodium boron hydride in NaOH 0.5 N. The microscopic analysis shown that the particles have an average size of 4% m (range 1-14 {mu} m). The velocity of sedimentation was 0.008 cm/min with high stability in vitro in human serum. The biological studies in healthy rabbits, shown that the complex is retained inside the articulation still eight days after of the administration of the radiopharmaceutical. Likewise, it is presented the data of absorbed dose in the different target organs, which was determined by thermoluminescent dosimetry (TLD) through the use of a REMCAL phantom (radiation equivalent manikin calibration). (Author)

1999-07-01

146

Optimized sizing model for renewable energy systems in rural areas; Modelo de dimensionamento otimizado para sistemas energeticos renovaveis em ambiente rurais  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this research was to develop a methodology for sizing integrated renewable energy systems, useful for rural areas, using simulation and optimization tools developed in MATLAB 6.0. The sizing model produces a system with minimum cost and high reliability level, based on the concept of loss of power supply probability (LPSP) for consecutive hours. An optimization model is presented and three different sizing scenarios are calculated and compared, showing flexibility in the elaboration of different project conceptions. The obtained results show a complete sizing of the energy conversion devices and a long-term cost evaluation. (author)

2005-05-15

147

New High-Pressure Excitations in Parahydrogen  

Energy Technology Data Exchange (ETDEWEB)

Raman and infrared spectroscopy of para-H{sub 2} to pressures in excess of 200GPa and to 8K using new ultrapure synthetic diamond anvils reveals numerous new vibrational excitations in the three high-pressure phases. Highly resolved Raman-active librons indicate differences in orientational ordering between phasesII and III, including evidence for changes within phaseII. The librons in phaseIII are strongly pressure dependent and reflect a substantial increase in ordering with pressure. Multiple vibrons in all three phases (I, II, and III) are observed. The results place new bounds on predicted crystal structures and dynamics of the dense molecular solid. {copyright} {ital 1997} {ital The American Physical Society}

1998-01-01

148

Implantation of an electronic system for real time neutron graphic images acquisition at the IPEN/CNEN Argonaut reactor; Implantacao de um sistema eletronico para aquisicao de imagens neutrongraficas em tempo real no reator Argonauta do IEN/CNEN  

Energy Technology Data Exchange (ETDEWEB)

The aim of this work is the implantation and characterization of a neutron radiography system that uses an electronic device for attainment of images in real time, for its implementation in the nuclear research reactor Argonauta at IEN/CNEN (Nuclear Engineering Institute of the Brazilian Nuclear Energy Commission). The Electronic Imaging System in Real Time is composed by a scintillator screen for neutron, a video camera (CCD), a digital plate and a computer with specific computational programs for digital processing of the images. The System in installed real time is apt to carry through neutron radiography inspections of static and dynamic events of several types of samples. (author)

2004-04-15

149

Fusion of protoplasts with irradiated micro protoplasts as a tool for radiation hybrid panel in citrus;Fusao de protoplastos com microprotoplastos irradiados como ferramenta para painel hibrido de radiacao em citros  

Energy Technology Data Exchange (ETDEWEB)

The objective of this work was to combine asymmetric somatic hybridization (donor-recipient fusion or gamma fusion) to microprotoplast-mediated chromosome transfer, as a tool to be used for chromosome mapping in Citrus. Swinglea glutinosa micro protoplasts were irradiated either with 50, 70, 100 or 200 gamma rays and fused to cv. Ruby Red grapefruit or Murcott tangor protoplasts. Cell colonies were successfully formed and AFLP analyses confirmed presence of S. glutinosa in both 'Murcott' tangor and 'Ruby Red' grapefruit genomes. (author)

2009-12-15

150

Evolutionary implications of morphogenesis and molecular patterning of the blind gut in the planarian Schmidtea polychroa  

British Library Electronic Table of Contents (United Kingdom)

The formation of a through-gut was a key innovation in the evolution of metazoans. There is still controversy regarding the origin of the anus and how it may have been either gained or lost during evolution in different bilaterian taxa. Thus, the study of groups with a blind gut is of great importance for understanding the evolution of this organ system. Here, we describe the morphogenesis and molecular patterning of the blind gut in the sexual triclad Schmidtea polychroa. We identify and analyze the expression of goosecoid, commonly associated with the foregut, and the GATA, ParaHox and T-box genes, members of which commonly are associated with gut regionalization. We show that GATA456a is expressed in the blind gut of triclads, while GATA456b is localized in dorsal parenchymal cells. Goo...

2011-01-01

151

Applicator reconstruction and applicator shifts in 3D MR-based PDR brachytherapy of cervical cancer  

British Library Electronic Table of Contents (United Kingdom)

Purpose To evaluate the methods of applicator reconstruction in 3D MR-based planning for brachytherapy of cervical cancer, and to investigate applicator shifts and changes in DVH parameters during PDR treatment. Methods For each application MR scans with applicator in situ were made: three T2-weighted (4.5mm slices) Turbo Spin Echo (TSE) scans and a balanced Steady State Free Precession scan (1.5mm). Three observers tested two applicator reconstruction methods: (A) directly on the bSSFP scan and (B) on a resampled combination of the three T2-weighted scans. For 10 patients MR imaging was repeated on the second day of each PDR fraction to determine applicator shifts and changes in DVH parameters. Results For both applicator reconstruction methods the interobserver variation for the DVH para...

2009-01-01

152

Acid pre-hydrolysis of biomass as a preparation process for its utilization as thermoelectric power plants fuel; Pre-hidrolise acida da biomassa como preparacao de combustivel para termoeletrica  

Energy Technology Data Exchange (ETDEWEB)

It is described a process of production of celulignin from biomass through acid pre-hydrolysis in continuous reactor made of advanced materials such as niobium, titanium and monel. The celulignin is a fuel of 28.50 MJ/kg of heating power. The utilization of this technology together with eucalyptus reforestation by vegetative propagation and high efficiency thermoelectric plant (triple cycle of steam turbine, gas turbine and MHD electrical generation) allow electric power production with competitive cost when compared to hydroelectric power. (author). 1 ref. 5 figs., 2 tabs

1990-12-31

153

A measurement of the parity-violating gamma-ray asymmetry in the neutron-proton capture  

Energy Technology Data Exchange (ETDEWEB)

The {rvec n} + p {yields} d + {gamma} experiment under construction at LANSCE studies the weak interaction between neutrons and protons. The experiments will measure the directional dependence of the parity-violating {gamma}-ray asymmetry, A{sub {gamma}}, in the polarized cold neutron capture by para-hydrogen. The goal is to measure A{sub {gamma}} with uncertainty of 0.5 x 10{sup -8}, 10% of its predicted value. A{sub {gamma}} primarily isolates the {Delta}I = 1 component of the hadronic weak interaction and thus will determine the long-range weak pion-nucleon coupling constant H{sub {pi}}{sup 1}. The experiment is carefully designed for the LANSCE pulsed spallation neutron source to achieve the proposed statistical precision and to control systematic errors. We discuss the experiment and its status.

2002-01-01

154

Stent-assisted recanalization of atherosclerotic intracranial stenosis  

International Nuclear Information System (INIS)

Intracranial atherosclerosis is a major cause of ischemic stroke, and depending on the studied population, it accounts for 8%-15% of all strokes that are due to cerebral atherosclerosis. The prognosis of patients with symptomatic intracranial stenoses seems to depend on the location and extent of intracranial atherosclerosis. Currently, the primary treatment in intracranial atherosclerosis is the control of vascular risk factors such as hypertension, diabetes, hypercholesterolemia, and smoking. Secondary prevention with antiplatelet therapy has been shown to reduce the risk of subsequent vascular events in patients who have suffered a recent ischemic stroke or transient ischemic attack (TIA). Unfortunately, a significant number of patients with intracranial atherosclerosis continue to suffer from repeated strokes or TIA despite maximal medical treatment. Although endovascular revascularization for symptomatic intracranial stenoses remains at ...

2006-09-01

155

Relaxant effects of hexosamines on isolated small human placental arteries  

DEFF Research Database (Denmark)

Wharton's jelly contains large amounts of hyaluronic acid, and glucosamine is an important constituent of this macromolecule. In order to evaluate the placental vascular effects of this aminosugar, small chorionic and stem villous arteries were dissected from placental specimens obtained at normal term vaginal deliveries (n = 15). Ring preparations were mounted in organ baths, and isometric wall tensions were measured. Glucosamine and its epimer galactosamine (5 X 10(-4) to 10(-2) M) produced marked relaxation of contractions induced by PGF2 alpha (10(-5) M) in both chorionic and stem villous arteries. The effect was unchanged after pretreatment with atropin, propranolol and indomethacin. The relaxant effect of the neutral sugar mannose was less pronounced compared with that of the hexosamines. Total tissue concentrations of placental hexosamines have been reported within the range needed to produce placental vascular relaxation in the present ...

1987-01-01

156

MR imaging and MR cholangiopancreatography in the preoperative evaluation of hilar cholangiocarcinoma: correlation with surgical and pathologic findings  

International Nuclear Information System (INIS)

The primary aim was to evaluate delayed contrast-enhanced MRI in depicting perineural spread of hilar cholangiocarcinoma (CCC) and consequently to determine the capability of MRI/MRCP for staging CCC. Fifteen patients that underwent MRI/MRCP and surgical treatment were retrospectively included. Two radiologists evaluated MR images to assess delayed periductal enhancement, extent of bile duct stenosis, liver parenchymal and vascular involvement and presence of liver atrophy. An agreement between delayed enhancement of the bile duct walls and perineural neoplastic spread showed a very good correlation factor (0.93). The overall accuracy in detecting biliary neoplastic invasion was higher for delayed T1-weighted images (93.3%) than for the MRCP images (80%), and T1-delayed image increased the MR accuracy in assessing the neoplastic resectability (p < 0.05). MRI correctly predicted vascular involvement in 73% and liver involvement in 80% of the ...

2008-10-01

157

Computed tomography (CT) in renal trauma  

International Nuclear Information System (INIS)

CT scans were performed on 25 patients suspected of sustaining ranal trauma. The utility of CT in both detecting renal damage and appraising the gravity of injuries was assessed. Nowadays, in fact, nephrectomy or reserved for lesions devastanting the kidney parenchyma or rupturing the renal pedicle; so it is very important to identyfy both the purposes of a better planned therapeutic approach. CT does both, being more accurate than urography in the detection of renal fractures, intra or extraparenchymal hematomas and contrast media extravasation. Urography very often shows aspecific lesion patterns and sometimes it is also falsely negative. In the present series CT was more reliable than angiography itself, particulary in the diagnosis of extra-renal hematic collections, contrast media extravasation and injuries to the other abdominal organs. Although CT may arouse the suspicion of and sometimes correctly diagnose vascular lesions, such as renal infarction, ...

1987-01-01

158

Blunt renal trauma in children: healing of renal injuries and recommendations for imaging follow-up  

International Nuclear Information System (INIS)

Initial CT grading of renal injury was correlated with the frequency of complications and the time course of healing in 35 children. All renal contusions (grade 1, 8) and small parenchymal lacerations (grade 2, 8) healed without complications. All lacerations extending to the collecting system (grade 3, 9) resulted in mild to severe loss of renal function with progressive healing over 4 months. One of four segmental infarcts (grade 4 A), and five of six vascular pedicle injuries (grade 4 B) resulted in severe loss of renal function. Complications, including urinoma (2), sepsis (1), hydronephrosis (1), and persistent hypertension (2), were limited to grade 3 and 4 injuries. Our results suggest that mild renal injuries do not require follow-up imaging. Major renal lacerations and vascular pedicle injuries, however, often result in loss of renal function and should be followed up closely due to the risk of delayed complications. Follow-up ...

159

Bevacizumab as a treatment option for radiation-induced cerebral necrosis  

International Nuclear Information System (INIS)

Radiation necrosis of normal CNS tissue represents one of the main risk factors of brain irradiation, occurring more frequently and earlier at higher total doses and higher doses per fraction. At present, it is believed that the necrosis results due to increasing capillary permeability caused by cytokine release leading to extracellular edema. This process is sustained by endothelial dysfunction, tissue hypoxia, and subsequent necrosis. Consequently, blocking the vascular endothelial growth factor (VEGF) at an early stage could be an option to reduce the development of radiation necrosis by decreasing the vascular permeability. This might help to reverse the pathological mechanisms, improve the symptoms and prevent further progression. A patient with radiation-induced necrosis was treated with an anti-VEGF antibody (bevacizumab), in whom neurologic signs and symptoms improved in accordance with a decrease in T1-weighted fluid-attenuated ...

2011-02-01

160

Benzyl carbamyl analogue of lignocaine: vasodepressor mechanism of action.  

Science.gov (United States)

1. The benzyl carbamyl analogue of lignocaine [2-(diethylaminoacetamido)-3-carbamyl-4-methyl-5-benzylpyrrole] at an intravenous dose of 4 mg/kg caused a blood pressure decrease of 54 mmHg. 2. A greater hypotensive effect was observed in hypertensive compared to normotensive animals. Anaesthesia magnified the vasodepressor effect in both groups. 3. The analogue did not possess centrally-mediated effects on blood pressure but exerted its hypotensive effect via a peripheral mechanism. 4. The analogue produced a relaxant effect on intestinal and vascular smooth muscle while exerting minimal effects on muscarinic, sympathetic, or ganglionic nicotinic receptors. 5. The analogue exhibited less cardiac depressant action on left ventricular rate (dp/dt) and force of contraction than lignocaine. 6. Lethal effects for the analogue were first observed at 16 mg/kg following intravenous administration and at 500 mg/kg following intraperitoneal administration. 7. In conclusion, ...

161

Angiogenic cytokines and growth factors in systemic sclerosis.  

Science.gov (United States)

Systemic sclerosis is an autoimmune connective tissue disorder characterized by a widespread microangiopathy, autoimmunity and fibrosis of the skin and of various internal organs. Microangiopathy is characterized by a reduced capillary density and an irregular chaotic architecture that lead to chronic tissue hypoxia. Despite the hypoxic conditions, there is no evidence for a sufficient compensative angiogenesis in SSc. Furthermore, vasculogenesis is also impaired. An imbalance between angiogenic and angiostatic factors might explain the pathogenetic mechanisms of SSc vasculopathy. As far as angiogenic factors are concerned, within the most important are vascular endothelial growth factor (VEGF) and its receptors, platelet derived growth factor (PDGF), transforming growth factor beta (TGF-?), fibroblast growth factor -2 (FGF-2), angiopoietin 1 (Ang-1), stromal cell-derived factor 1 (SDF-1/CXCL12), endothelin-1 (ET-1), monocyte chemoattractant protein -1 (MCP-1), ...

2011-04-28

162

cap alpha. -2 adrenergic receptor: a radiohistochemical study  

Energy Technology Data Exchange (ETDEWEB)

..cap alpha..-2 adrenergic agents have been shown to influence blood pressure, heart rate and other physiological and behavioral functions through interactions with adrenergic pathways within the central nervous system. Pharmacologically relevant ..cap alpha..-1 adrenergic receptors were biochemically characterized and radiohistochemically analyzed in intact tissue sections of the rat and human central nervous system. The anatomical distribution of the ..cap alpha..-2 receptors, labeled with the agonist (/sup 3/H)para-aminoclonidine, verified the concept that ..cap alpha..-2 receptors are closely associated with adrenergic nerve terminals and that ..cap alpha..-2 agents can influence autonomic and endocrine function through an action in the central nervous system. Since ..cap alpha..-2 agonists can influence sympathetic outflow, ..cap alpha..-2 binding sites were closely analyzed in the intermediolateral cell column of the thoracic spinal cord. The transport of ...

1984-01-01

163

A Liquid Parahydrogen Target for the Measurement of a Parity-violating Gamma Asymmetry in Polarized Neutron Capture on Protons  

Energy Technology Data Exchange (ETDEWEB)

A 16 l liquid parahydrogen target has been developed for a measurement of the parity-violating {gamma}-asymmetry in the capture of polarized cold neutrons on protons in the {rvec n} + p {yields} d + {gamma} reaction by the NPDGamma collaboration. The target system was carefully designed to meet the stringent requirements on systematic effects for the experiment and also to satisfy hydrogen safety requirements. The target was designed to preserve the neutron polarization during neutron scattering on liquid hydrogen (LH{sub 2}), optimize the statistical sensitivity to the {rvec n} + p {yields} d + {gamma} reaction, minimize backgrounds coming from neutron interaction with the beam windows of the target cryostat, minimize LH{sub 2} density fluctuations which can introduce extra noise in the gamma asymmetry signal, and control systematic effects. The target incorporates two mechanical refrigerators, two ortho-para convertors, an aluminum cryostat, an aluminum target ...

2010-05-01

164

The role of interventional radiology in management of patients with end-stage renal disease  

Energy Technology Data Exchange (ETDEWEB)

The aim of the paper is to review the role of interventional radiology in the management of hemodialysis vascular access and complications in renal transplantation. The evaluation of patients with hemodialysis vascular access is complex. It includes the radiology/ultrasound (US) evaluation of the peripheral veins of the upper extremities with venous mapping and the evaluation of the central vein prior to the access placement and radiological detection and treatment of the stenosis and thrombosis in misfunctional dialysis fistulas. Preoperative screening enables the identification of a suitable vessel to create a hemodynamically-sound dialysis fistula. Clinical and radiological detection of the hemodynamically significant stenosis or occlusion demands fistulography and endovascular treatment. Endovascular prophylactic dilatation of stenosis greater than 50% with associated clinical abnormalities such as flow-rate reduction is warranted to ...

2003-05-01

165

Probable role of trace elements of some medicinal plants in cardio-vascular diseases  

International Nuclear Information System (INIS)

A number of herbal drugs are used in the Unani (Greco-Arab) System of Medicine for cardiovascular diseases. The herbs were analyzed by flame AAS and ICP-AES to determine if their therapeutic actions can be associated with the elements present in them. Cadmium, cobalt, chromium, copper, iron, potassium, magnesium, manganese, sodium, nickel, phosphorus, lead and zinc were some of the elements which play various roles in cardiovascular affections. An effort was made to correlate the role of these elements in cardiac diseases. (Auth.). 2 tabs., 32 refs.

166

Posttraumatic tibia valga: a case demonstrating asymmetric activity at the proximal growth plate on technetium bone scan  

Energy Technology Data Exchange (ETDEWEB)

Posttraumatic tibia valga is a well-recognized complication following fracture of the upper tibial metaphysis in young children. We present a case of a child who developed a valgus deformity following fracture of the proximal tibia and fibula in which quantitative bone scintigraphy at 5 months after injury demonstrated increased uptake at the proximal tibial growth plate with proportionally greater uptake on the medial side. This finding suggests that the valgus deformity in this patient was due to a relative increase in vascularity and consequent overgrowth of the medial portion of the proximal tibial physis.

1987-07-01

167

Posttraumatic tibia valga: a case demonstrating asymmetric activity at the proximal growth plate on technetium bone scan  

International Nuclear Information System (INIS)

Posttraumatic tibia valga is a well-recognized complication following fracture of the upper tibial metaphysis in young children. We present a case of a child who developed a valgus deformity following fracture of the proximal tibia and fibula in which quantitative bone scintigraphy at 5 months after injury demonstrated increased uptake at the proximal tibial growth plate with proportionally greater uptake on the medial side. This finding suggests that the valgus deformity in this patient was due to a relative increase in vascularity and consequent overgrowth of the medial portion of the proximal tibial physis.

168

Avascular necrosis associated with nailing of femoral neck fracture  

Energy Technology Data Exchange (ETDEWEB)

Two patients with femoral neck fractures, one displaced and one undisplaced, are presented. Preoperative intravital staining with tetracycline and Tc-MDP scintimetry both showed intact femoral head circulation while Tc-MDP-scintimetry 1 week after operation showed pronounced circulatory deficiency. Sr/sup 85/-scintimetry performed at the same time was inconclusive. Segmental collapse was observed radiographically, 8 and 12 months postoperatively. The major vascular injury resulting in avascularity most probably occured during the procedure of osteosynthesis, and Tc-MDP-scintimetry was found suitable for early postoperative recognition of avascular necrosis in both fractures.

1983-01-01

169

Avascular necrosis associated with nailing of femoral neck fracture  

International Nuclear Information System (INIS)

Two patients with femoral neck fractures, one displaced and one undisplaced, are presented. Preoperative intravital staining with tetracycline and Tc-MDP scintimetry both showed intact femoral head circulation while Tc-MDP-scintimetry 1 week after operation showed pronounced circulatory deficiency. SR"8"5-scintimetry performed at the same time was inconclusive. Segmental collapse was observed radiographically, 8 and 12 months postoperatively. The major vascular injury resulting in avascularity most probably occured during the procedure of osteosynthesis, and Tc-MDP-scintimetry was found suitable for early postoperative recognition of avascular necrosis in both fractures. (author).

170

Pioglitazone does not affect vascular or inflammatory responses after endotoxemia in humans.  

Science.gov (United States)

PPARgamma agonists have been proposed to exert more than metabolic benefits, particularly by anti-inflammatory mechanisms. We hypothesized that pioglitazone might modulate inflammatory and vascular responses to lipopolysaccharide (LPS). In a placebo-controlled parallel-group study in 18 healthy male subjects, the E. coli endotoxin model of inflammation (20 IU/kg i. v.) was employed to test the effect of 60 mg pioglitazone over nine days on inflammatory cytokines. Macrovascular function and microvascular blood flow were assessed by brachial artery ultrasound and retinal blood flow parameters, respectively. Pioglitazone increased brachial artery diameter by 5.6% but had no effect on other outcome parameters under resting conditions. LPS increased cytokine levels to peak concentrations of 91.3+/-22.5 ng/ml (IL-6), 261.4+/-60.0 ng/ml (TNFalpha), and 524.5+/-15.3 ng/ml (VCAM-1). The endotoxin caused microvascular vasodilation and increased retinal white blood cell flux, ...

2008-05-21

171

Patterns of proliferation related to vasculature in human head-and-neck carcinomas before and after transplantation in nude mice  

International Nuclear Information System (INIS)

Purpose: The predictive potential of tumor cell kinetic parameters may be improved when they are studied in relation to other microenvironmental parameters. The purpose of this investigation was to quantitatively categorize human tumor samples according to proliferation patterns. Second, it was examined whether these characteristics are retained after xenotransplantation. Methods and Materials: Fifty tumor samples from head-and-neck cancer patients were immunohistochemically stained for Ki-67 and vessels. Also, parts of the samples were transplanted into nude mice. Tumors were categorized according to previously described patterns of proliferation. Vascular and proliferation patterns were analyzed using an image processing system. Results: The 50 tumors were categorized into four patterns of proliferation by visual assessment: marginal (6), intermediate (10), random (21), and mixed (12). One tumor could not be classified. These patterns were quantified by ...

2001-12-01

172

Update on erectile dysfunction treatment for aging men  

British Library Electronic Table of Contents (United Kingdom)

Resumen Estudios epidemiologicos recientes, muestran claramnete la incidencia de la disfuncion erectil con la edad. Por lo tanto, los profesionales sanitarios que se ocupan de las personas de edad avanzada, deberian preparar cuidadosamente el diagnostico y el abordaje de la disfuncion erectil. Es innegable que la introduccion de los inhibidores de la fosfodisterasa tipo 5 (PDE5Is) ha revolucionado el tratamiento de la disfuncion erectil. Los clinicos deberian conocer el potencial de los efectos adversos asociados con el uso de PDE5Is cuando se aconseja a los pacientes. Otras terapias suplementarias y de segunda/tercera linea para la disfuncion erectil, que incluyen las inyecciones intracavernosas, la aplicacion transuretral de medicacion, la testosterona, los sistemas de vacion peneano, la...

2008-01-01

173

Type tests to the automatic thermoluminescent dosimetry system acquired by the CPHR for personal dosimetry; Pruebas tipo al sistema de dosimetria termoluminiscente automatico adquirido por el CPHR para dosimetria personal  

Energy Technology Data Exchange (ETDEWEB)

The CPHR individual monitoring service acquired an automatic RADOS TLD system to improve its capacities to satisfy the increasing needs of their national customers. The TLD system consists of: two automatic TLD reader, model DOSACUS, a TLD irradiator and personal dosimeters card including slide and holders. The dosimeters were composed by this personal dosimeters card and LiF:Mg,Cu,P (model GR-200) detectors. These readers provide to detectors a constant temperature readout cycle using hot nitrogen gas. In order to evaluate the performance characteristics of the system, different performance tests recommended by the IEC 1066 standard were carried out. Important dosimetric characteristics evaluated were batch homogeneity, reproducibility, detection threshold, energy dependence, residual signal and fading. The results of the tests showed good performance characteristics of the system. (Author)

2006-07-01

174

The importance of the treatment of the unsafe acts for the prevention of accidents in petrochemical industry; A importancia do tratamento dos atos inseguros para a prevencao de acidentes na industria petroquimica  

Energy Technology Data Exchange (ETDEWEB)

Due to the fact that, the workers' behavior is characterized by its complexity and diversity, this issue has been seen as a great 'black box' in discussions regarding the Management Systems of SHE. Associated with this issue other arises: How conscious people? How to engage them with the process? How to improve the risk control? How to motivate the prevention? Most of these responses are discussed in the Social and Human Sciences for many years. However, it is necessary to closer the technical-operational knowledge and the human aspects, applying in the organizations' daily work, to make the working environment more safe. The purpose of this study, therefore, is examining the possibility of reducing accidents through the identification and treatment of deviations (unsafe acts and unsafe conditions), cause the whole accident, be it serious or not, begins with a small deviation. It was used as a reference tool, the Behavior audit and it is based on ...

2008-07-01

175

The Muhlbauer method for pipeline risk management in onshore environment; O metodo de Muhlbauer para gerenciamento de risco em linhas de dutos em ambiente 'onshore'  

Energy Technology Data Exchange (ETDEWEB)

There are several methods for the risk assessment and risk management applied to pipelines, among them the Muhlbauer's Method. W. Kent Muhlbauer is an internationally recognized authority on pipeline risk management. He made a detailed identification about 300 distinct conditions that influence the risk assessment in pipelines and he proposed a score system that is known as method of Muhlbauer. The purpose of this model is to evaluate the public exposure to the risk and identify ways for management that risk in fact. The assessment is made by the attribution of quantitative values to the several items that influences in the pipeline risk. This paper approaches the Muhlbauer's basic model for risk assessment and management in pipelines. In the beginning, the basic model for risk assessment is presented, and methodology for pipelines in onshore environment is detailed. After, presents major items in risk assessment and this relative score. Finally, present the ...

2008-07-01

176

Systematic review and gamma radiosensitivity of medicinal plants: development of protocol for quality control; Revisao sistematica e radiossensitividade gama de plantas medicinais: desenvolvimento de protocolo para controle de qualidade  

Energy Technology Data Exchange (ETDEWEB)

The present study discusses the contribution of the adoption of more rigorous and objective criteria to the selection and analysis of information sources, leading to more scientific rigour when registering phytotherapic drugs. To this end, it is herein proposed the adoption of a previously tested and acknowledged methodology, namely the Systematic Revision, as a standard for phytotherapic drug analyses. In order to show differences brought about by the Systematic Revision during the registration procedures of phytotherapic drugs, the case of the Maytenus ilicifolia (known popularly in Brazil as 'espinheira-santa') is presented. As it is well known, the use of ionizing radiation is expanding, especially in medicine and pharmacy. Therefore, gamma radiation was applied to the microbiological quality control of phytotherapic matrices. Results indicated a positive contribution of Systematic Revision to the registration procedures of phytotherapic drugs, as well as the ...

2006-07-01

177

Reversible downregulation of endocrine and germinative testicular function (hormonal castration) in the dog with the GnRH-Agonist Azagly-Nafarelin as a removable implant "Gonazon"; a preclinical trial  

British Library Electronic Table of Contents (United Kingdom)

Downregulation of anterior pituitary GnRH-receptors by application of a slow release GnRH-implant offers an effective and reversible alternative to surgical castration of the male dog. Aim of the present study was to test the efficacy and the underlying mechanisms of a new non-biodegradable controlled-release device implant (Gonazon, Intervet, containing 18.5mg of the GnRH-agonist Azagly-Nafarelin). Eight male beagle dogs were implanted s.c. at the para-umbilical region. In four dogs implant removal was after 180 days (group 1), in the other four dogs after 365 days (group 2). Eleven weeks after implantation availability of LH was reduced (p<0.0001) by 70%. After an initial increase lasting for about 4 days, testosterone (T) and estradiol (E2) concentrations decreased (p<0.0001) to basal l...

2009-01-01

178

Produced water treatment using polymeric resins; Resinas polimericas para tratamento da agua produzida  

Energy Technology Data Exchange (ETDEWEB)

The treatment and disposal of oily waters from oil production and refining processes represent an important technological pass for attendance of the ambient legislation and to the politics of the Cia of search of the environmental excellence. The reuse or reinjection of the co-produced water has been considered an interesting strategical alternative, however, the water quality requirement for these processes demands a pretreatment step, considering the exit effluent from primary and secondary treatment processes currently used. This work presents resulted of the polymeric resin development for tertiary treatment of oily waters with low oil and grasses content and fine solids, including the dissolved fraction. These resins can adsorb, in reversible form, organic components. Its high adsorption capacity is determined by the polarity, superficial area, range of porosity and a wide distribution of particle size and pore. Another important characteristic is the possibility of its use in ...

2008-07-01

179

Problems of waste disposal in the handling of natural radioactive material not subject to authorisation  

International Nuclear Information System (INIS)

With the exception of some minerals, the specific activity of natural radioactive material is below 370 Bq/g, their handling thus not being subject to authorization or the duty of reporting according to section 4 para. 2 of the Radiological Protection Ordinance. Moreover, there is required no handling license for prospecting, mining and processing of radioactive minerals; they are subject to the procedures for the plans of operation of the mining laws of the Federal States. License-free handling of natural radioactive material may result in the production of radioactive waste, the disposal of which must be authorized according to sect. 47 of the Radiological Protection Ordinance if the specific activity exceeds the free amounts of column 4 in Table IV of Appendix IV by a factor of 10"-"4/g. This inconsistency is discussed by means of the following examples: (1) fly ash and slag from coal power plants, (2) flue dust from sintering plants, (3) red mud from aluminium ...

1980-05-01

180

New technology for the emulsification of petroleum residuals in water; Nueva tecnologia para la emulsificacion de residuales del petroleo en agua  

Energy Technology Data Exchange (ETDEWEB)

It turns out of interest to Comision Federal de Electricidad and Petroleos Mexicanos to reduce costs of fuel oil, reducing the viscosity of the residues petroleum of high vacuum distillation emulsifying these with water. The parameters that define the characteristics of the emulsions are mainly the relation of their components, viscosity, size and drop distribution and its stability. The experimental work began producing emulsions in form of lots, using samples of approximately 500 milliliters of vacuum residue. In this first stage, at different concentrations, were examined eight different surfactants, as well as combinations among them, also seven different stabilizers were used. With these tests it has been managed to identify the concentrations, as well as the most adequate relations of surfactants and stabilizers for the production of emulsions of vacuum residues in water. The size and drop distribution has been determined by means of an optical LEICA microscope, model DMLS, that ...

2001-07-01

181

Models comparative study for heat storage in fixed beds; Estudo comparativo de modelos para armazenamento de calor em leitos fixos  

Energy Technology Data Exchange (ETDEWEB)

This work presents comparative results of a numerical investigation of four possible models for the prediction of thermal performance of fixed bed storage units and their thermal design. These models includes Schumann's model, the radial dispersion model, a model that include both axial heat conduction in the fluid phase and admits thermal gradient in the solids particles and finally a two dimensional single phase model. For each of these models a computer code was written and tested to evaluate the computing time of same data and analyze any other computational problems. The tests of thermal performance included particle size, porosity, particle material, flow rate, inlet temperature and heat losses form tank walls and extremities. Dynamics behaviour of the storage units due to transient variation in either flow rate or inlet temperature was also investigated. The results presented include temperature gradients, pressure drop and heat storage. The results obtained are very ...

1991-07-01

182

Methodology to evaluate the energy associated to the industrial solid wastes: application in a metropolitan region of Campinas, Sao Paulo state, Brazil; Metodologia para avaliacao da energia associada ao residuo solido industrial: aplicacao a regiao metropolitada de Campinas  

Energy Technology Data Exchange (ETDEWEB)

The aim of this work is to the application of a methodology to evaluate the energy associated to the industrial solid wastes in the metropolitan region of Campinas. The methodological route proposed is: the characterization of the research area and the production/management of the industrial solid wastes; the energetic classification and the qualitative/quantitative research of the energy associated to the industrial solid wastes; and, the valuation of the applicability of the energetic utilization mechanisms proposed to the region. This methodology when applied at the Campinas metropolitan region proved to be valid and it resulted in a synthetically presentation of the social and environmental reality of the industrial sector and the destination of the wastes, as well as it indicated the potentialities related to the energetic utilization of the industrial solid waste in the region. With the obtained results it was shown the importance of the the production and the destination of the ...

2004-07-01

183

Humidity extraction and biomass chemical composition of the elephant-grass cultivated for energetic purposes; Extracao da umidade e composicao quimica da biomassa de capim-elefante cultivado para fins energeticos  

Energy Technology Data Exchange (ETDEWEB)

The experiment was conducted at the laboratory of Experimental Station of Instituto Agronomico de Campinas, in Piracicaba, SP, BR. The elephant-grass (Penissetum purpureum Schum) cv Guacu, with 6 months of development was chopped in a forage chopper regulated to cut biomass in pieces of 5 mm. 500 grams of chopped biomass was pressed in a hydraulic presser regulated for 60, 120, 180, 240 and 300 kg/cm{sup 2}. For the pressure of 60, 120, 180 and 240 kg/cm{sup 2} the presser was used in manual module, while, for the pressure of 300 kg/cm{sup 2} it was operated in the automatic module. The experiment was executed in randomized block design with 4 repetitions. When the pressure of 300 kg/cm{sup 2} was used it was extracted 21.78 % of the moisture of biomass, while the nitrogen percentage was little altered by press. (author)

2002-07-01

184

Explosion confinement system for exploitations by sublevels; Sistema de Confinamiento de Explosiones para Explotaciones por Subniveles  

Energy Technology Data Exchange (ETDEWEB)

The objective of this project was to develop a explosion suppression system capable to confine and extinguish gas explosions of the type produced in sub level caving faces when blasting to the coal pillar. Existing systems, such as triggered barriers, were considered not to be valid because of size, weight, cost, and other operational constraints. The research activities have been focused in the development of a mixed water/air spray system that should be manually activated some second before blasting. Two prototypes have been developed and tested, the first one using nozzle operating at the standard ranges of pressure that are normally available in underground coal mines, and a second one based in high-pressure nozzles. In this case, bottles containing a pressurized air/water mixtures are required. The works carried out included theoretical studies, hydraulic nozzles characterization, and modelling of the explosion phenomena using the AutoReaGas code. Besides, extensive testing of the ...

1999-11-01

185

Evaluation of red mud as pozzolanic material in replacement of cement for production of mortars; Avaliacao da lama vermelha como material pozolanico em substituicao ao cimento para producao de argamassas  

Energy Technology Data Exchange (ETDEWEB)

Red mud is a by-product of the alkaline extraction of aluminum from the bauxite and represents a renewed environmental problem due the significant annual throughput by the plants. In the present work, the pozzolanic properties of Brazilian red mud fired at 600, 700, 800 and 900 deg C were investigated by monitoring lime consumption using DTA analysis and Brazilian standard methodology NBR 5772 (1992). Products and kinetics of hydration were determined in cement pastes produced with 5 and 15% red mud using x-ray diffraction and DTA analysis. Compressive strength and capillary absorption tests were realized on mortars constituted by 5, 10 and 15% red mud in replacement of cement. When calcined at 600 deg C, the red mud develops good pozzolanic properties, and the compressive strength of mortars produced with this waste meet values in accordance with regulatory standard. These results shown than red mud can be used, in partial replacement of cement, as new construction material to produce ...

2010-07-01

186

Development of polymeric coatings for submerse flexible lines; Desenvolvimento de revestimentos polimericos para linhas flexiveis submersas  

Energy Technology Data Exchange (ETDEWEB)

The major objective of this work is to seek for new solutions that can lead to significant lifetime improvement of submerse lines which experience severe wear processes on the polymeric layer coating used for protection of the touch down point (TDP) region. Four different materials were selected as possible candidates for the coating layer of this critical region. They are commercially available and posses well known processing technologies. The materials are two polymers: nylon 66 and polyacetal; and two composites: nylon 66 reinforced with 13 or 33% glass fiber. Stress-strain behavior was evaluated using two deformation rates in order to characterize the viscoelastic behavior proper of polymeric materials. It was observed that increasing the amount of glass fiber in the matrix leads to a stronger material and a consequent decrease of elongation to break. Additionally, abrasion tests were carried out using a Taber equipment in three distinct conditions. Results indicate that nylon was ...

2003-07-01

187

Development of a new tool for predicting water quality. Verification on a stretch of the river Ebro; Desarrollo de una nueva herramienta para la prediccion de la calidad del agua. Verificacion en un tramo del rio Ebro  

Energy Technology Data Exchange (ETDEWEB)

The Water Frame work Directive (December 2000) proposes integrated water management in regard to both quality and quality. A mathematical model has therefore been produced at the CEIT and EPTISA research centre, in collaboration with the Ebro Hydrographic. Confederation (CHE), to predict water quality and thus begin integrated management of it in the river basins. A description is given of the characteristics of the simulation tool. The hydraulic model is based on the numerical (weighted, four-point implicit) resolution of the complete Saint Venant equations. The quality model is based on the IWA River Water Quality Model Number 1 which has clear advantages (consistency, mass balance and easy integration with the biological models of the waste water treatment plants and the collector networks compared to traditional models. The experimental validation, which includes calibration in wintertime of the hydraulic and quality models most representative coefficients was assessed on the basis ...

2004-07-01

188

Development of DP (Dynamic Positioning) to pull-in sub sea pipelines; Utilizacao de barcos de manuseio de ancoras operando com DP (Dynamic Positioning) para arraste de dutos submarinos  

Energy Technology Data Exchange (ETDEWEB)

Sub sea pipeline construction at oil and gas fields, with high concentration of on-bottom facilities, becomes more difficult when mooring operations and pipeline approach to a congested platform have to be performed. One method that has often been applied in Brazil is the so-called 'DP (Dynamic Positioning) pull-in', where PETROBRAS owned pipelay Barge, BGL-1, is moored away from the congested area, while a DP anchor handler pulls the rigid pipeline from BGL-1 to a target near the platform. The method was conceived to avoid mooring operations near the congested platforms as well as to minimize risks due to the pipeline initiation process. Inside the congested area the initiation with aid of a 'dead-man' anchor on the sea bottom, which would be a more conventional solution, becomes impossible in most cases. This paper will discuss the engineering work required to perform the 'DP pull-in' as well as show the operational steps, from ...

2004-07-01

189

Construction of a homogeneous phantom for radiographic image standardization; Construcao de um fantoma homogeneo para padronizacao de imagens radiograficas  

Energy Technology Data Exchange (ETDEWEB)

The principle of radiodiagnosis consists in the fact the X-ray beam is attenuated at different degrees by distinct tissues. For this reason, the anatomical structures have distinct radiological opacities, that produce the radiographic image. The progresses in radiology are related to the development if new radiographic image formation systems that enable an amplification in the quality, with low dose and/or risk to the patient. The objective of this work is the sensitometric valuation of a screen-film combination, that is still the most used, for the standardization, of radiographic images. Thinking about this, were constructed homogeneous phantoms of the chest, skull and pelvis, for the calibration of X-ray beams, with the purpose of obtaining radiographic images of good quality, basing in the routine of a radiodiagnosis service and in the scientific knowledge. Questions were approached about the choice of the suitable equipment, that allow the obtention of k Vp and m As combinations, ...

1996-12-31

190

Characterization of acai seeds as a feedstock for electricity generation via gasification; Caracterizacao do caroco de acai como insumo para geracao de eletricidade via gaseificacao  

Energy Technology Data Exchange (ETDEWEB)

This work presents an overview of the characterization physical-chemistry and energy of the aca pit used as input in process of generation of electricity through gasification. Acai pits analyses were accomplished with relationship to the acai pit drying, energy content, proximate and ultimate analyses, size, TGA experiments, bulk density. It was observed that the acai pit can be used as bioenergy but, it presents a low energy content (16,36 MJ/kg) in relationship that of the ' typical' biomass (21 MJ/kg ) and this is not due to the ash content that is very low (1,15%), but yes, the only composition that resembles each other more the Carbohydrates than to the typical composition of the usual biomass. The average diameter of 10 pits chosen at random was 9.5 mm. The acai pits have an angle of repose of {approx}20 degrees, making them ideal for feeding into gasification and combustion processes. (author)

2008-07-01

191

Calibration methods of plane-parallel ionization chambers used in electron dosimetry; Metodos de calibracao de camaras de ionizacao de placas paralelas para dosimetria de feixes de eletrons  

Energy Technology Data Exchange (ETDEWEB)

The use of linear accelerators in radiotherapy is of great importance in Medicine, and according to international recommendations the electron beam dosimetry has to be performed using plane-parallel ionization chambers, previously calibrated in standard gamma radiation fields at accredited laboratories. In this work, calibration methods of plane-parallel ionization chambers used in dosimetry procedures of high energy electron beams of clinical accelerators were presented, tested and intercompared. The experiments were carried out using gamma radiation beams of {sup 60} Co at the Calibration Laboratory of Clinical Dosemeters at IPEN and electron beams od 4 to 16 MeV at the Radiotherapy Department of Hospital Israelita Albert Einstein, Sao Paulo. A method was chosen to be established at IPEN. Proposals of the calibration procedure, calibration certificate and data sheets are presented. (author)

1999-07-01

192

An efficient method for 3-D pre stack migration in time reverse-time depth by using finite difference method; Um metodo eficiente para migracao pre-empilhamento 3-D em profundidade reversa no tempo pelo metodo das diferencas finitas  

Energy Technology Data Exchange (ETDEWEB)

Much of the current technology on 3D-prestack depth migration is based on the Kirchhoff method and the traveltime information needed for this purpose is obtained by the ray-theory approximation. The main motivation driving these options is to reduce computations but it can also have an adverse effect on the quality of results. Experience with real data indicates that the corresponding poststack data migrated by the reverse-time method often yields superior results. Considerable computational efficiency can be obtained by employing nonuniform coarse grid spacing during the reverse-time migration. We followed this strategy for developing a parallel scheme for doing 3D- prestack depth migration. However, we worked only on a small subset of shot gathers whose determined by the Quasi-Monte Carlo method. The results were indistinguishable from those obtained by using a much larger population of uniformly spaced shot gathers. We present examples of migration of 3-D data. (author)

1997-07-01

193

A decision support system to dynamic management of the scheduling workover rigs for onshore Potiguar Basin; Um sistema de apoio a decisao para o gerenciamento dinamico das sondas de producao terrestre da Bacia Potiguar  

Energy Technology Data Exchange (ETDEWEB)

The onshore Potiguar basin has nowadays around 5.000 artificial lifting petroleum wells, distributed into 80 fields located on the states of Rio Grande do Norte and Ceara, representing approximately 8% of the national oil production. For that, well maintenance service, realized by Workover Rigs, is essential to preserve the oil productivity of the reservoirs on these fields. However, as the number of rigs is lower than to the number of wells needing maintenance, the task of administrating the management of such equipment according to the demand created by the wells, generates an optimization problem. The decision for a rig intervention on a well depends on parameters such as flow rate, depth, wasted time on intervention, distance from the rig to the next well, type of operation, rig capacity, environmental risks, etc. The objective of this paper is to present an interactive Computational System for Support Decision to the optimized management of the wells attended by the rig fleet. ...

2004-07-01

194

[Pulmonary vascular manifestations in hereditary hemorrhagic telangiectasia].  

Science.gov (United States)

Hereditary hemorrhagic telangiectasia (Osler-Rendu-Weber disease) is a genetic disorder with autosomal dominance, variable penetrance, and an estimated prevalence of 1/10,000 inhabitants in France. Diagnosis is based on clinical criteria including epistaxis, telangiectasia, visceral manifestations, and familial occurrence. Pulmonary arteriovenous malformations, present in 15-33% of patients, are its primary visceral complications. The disease may be revealed by infectious and ischemic neurological manifestations due to paradoxical embolism. The high frequency of neurologic complications even in asymptomatic patients justifies systematic screening for pulmonary arteriovenous malformations. Treatment of these malformations is based on percutaneous transcatheter coil embolization of the feeding artery. Pulmonary arterial hypertension is rare in this disease. It may be due to systemic arteriovenous shunting in the liver, which increases cardiac output, or be similar to idiopathic pulmonary ...

2005-11-01

195

Xylem traits mediate a trade-off between resistance to freeze-thaw-induced embolism and photosynthetic capacity in overwintering evergreens  

British Library Electronic Table of Contents (United Kingdom)

Summary - Hydraulic traits were studied in temperate, woody evergreens in a high-elevation heath community to test for trade-offs between the delivery of water to canopies at rates sufficient to sustain photosynthesis and protection against disruption to vascular transport caused by freeze-thaw-induced embolism. - Freeze-thaw-induced loss in hydraulic conductivity was studied in relation to xylem anatomy, leaf- and sapwood-specific hydraulic conductivity and gas exchange characteristics of leaves. - We found evidence that a trade-off between xylem transport capacity and safety from freeze-thaw-induced embolism affects photosynthetic activity in overwintering evergreens. The mean hydraulically weighted xylem vessel diameter and sapwood-specific conductivity correlated with susceptibility to...

2011-01-01

196

Treatment of hepatocellular carcinoma (HCC) with radiolabeled Lipiodol: a preliminary report  

Energy Technology Data Exchange (ETDEWEB)

Fatty acid esters such as Lipiodol or Ethiodol are known to selectively localize in vascular hepatocellular carcinomas (HCC), following intraarterial hepatic administration. Lipiodol was labeled with radioactive /sup 131/I and administered in 47 patients with HCC for both imaging and therapy. The short term preliminary results suggest radiolabeled Lipiodol is effective in eliminating ascites, shrinking the tumor by a high internal radiation dose, and in improving symptomatology of these tumors. In the future, /sup 90/Y, which is a stronger pure beta-emitter (maximum beta energy of 2.27 MeV, a half life of 64 h, and a maximum penetration or beta range of 11mm), than /sup 131/I will be used for more effective treatment of HCC.

1987-12-01

197

The segmental gastrocnemius muscles' flap: A cadaveric study  

British Library Electronic Table of Contents (United Kingdom)

The aim of this study was to evaluate the feasibility of splitting each head of the gastrocnemius muscle into two segments. This prospective study was conducted on 35 fresh cadavers with injection of radio-opaque contrast material in the popliteal artery. Seventy medial gastrocnemius and 70 lateral gastrocnemius muscle specimens were obtained. Gastrocnemius intramuscular arterial anatomy was analysed by using the digital X-ray technique. The most common vascular pattern found in this study was both bellies supplied by individual sural arteries, which shows distal bifurcation. The medial sural artery always showed bifurcation in the medial gastrocnemius muscle in both lower limbs, whereas this bifurcation of the lateral sural artery was present in only 87% cases and 13% of cases showed a si...

2011-01-01

198

Somatic and genetic radiation exposure of the patient in digital subtraction angiography (DSA)  

International Nuclear Information System (INIS)

The somatic and genetic radiation exposure of patients undergoing Digital Subtraction Angiography (DSA) and traditional Film Arteriography (FA) of cranial, cervical, thoracic and abdominal vascular territories are compared. The radiation doses absorbed within the critical organs - red bone marrow, lung, thyroid gland and female breast - and in the gonads were measured using an anthropomorphic Alderson phantom. A Somatic Dose Index was calculated in order to estimate the somatic radiation risk. The somatic radiation exposure depends upon the location of the critical organs with respect to the entrance site of the x-ray beam, and can be reduced by an appropriate choice of the angiographic projection. Under this condition, the radiation exposure of the patient during DSA can be lower than during FA. For renal DSA an a.p. projection, the use of an abdominal compression device and careful caudal shielding of the field are advocated. (orig.).

1986-01-01

199

Small heat shock protein 20 (HspB6) in cardiac hypertrophy and failure  

British Library Electronic Table of Contents (United Kingdom)

Hsp20, referred to as HspB6, is constitutively expressed in various tissues. Specifically, HspB6 is most highly expressed in different types of muscle including vascular, airway, colonic, bladder, and uterine smooth muscle; cardiac muscle; and skeletal muscle. It can be phosphorylated at Ser-16 by both cAMP- and cGMP-dependent protein kinases (PKA/PKG). Recently, Hsp20 and its phosphorylation have been implicated in multiple physiological and pathophysiological processes including smooth muscle relaxation, platelet aggregation, exercise training, myocardial infarction, atherosclerosis, insulin resistance and Alzheimer's disease. In the heart, key advances have been made in elucidating the significance of Hsp20 in contractile function and cardioprotection over the last decade. This mini-rev...

2011-01-01

200

Serum gamma-glutamyltransferase is associated with arterial stiffness in healthy individuals  

British Library Electronic Table of Contents (United Kingdom)

Summary Objective- Gamma-glutamyltransferase (GGT) has been reported to be useful in predicting cardiovascular disease. Arterial stiffness measured by brachial-ankle pulse wave velocity (baPWV) is not only a marker of vascular damage but a significant predictor of cardiovascular events. Gender difference has been reported in the association between GGT and baPWV. We assessed, therefore, the association between GGT and baPWV in a large population and determined whether there was gender difference. Design- This cross-sectional study was conducted at the Asan Medical Centre, Seoul, Republic of Korea. Subjects and measurements- Serum GGT, baPWV and conventional risk factors were measured in 10 988 apparently healthy subjects (7248 men, 3740 women) who participated in a routine health screening...

2011-01-01

201

Role of cerebrospinal fluid pressure in the pathogenesis of glaucoma  

British Library Electronic Table of Contents (United Kingdom)

Abstract. The pathogenesis of normal (intraocular) pressure glaucoma has remained unclear so far. As hospital-based studies showed an association of normal-pressure glaucoma with low systemic blood pressure, particularly at night, and with vasospastic symptoms, it has been hypothesized that a vascular factor may play a primary role in the pathogenesis of normal-pressure glaucoma. That assumption may, however, be contradicted by the morphology of the optic nerve head. Eyes with normal-pressure glaucoma and glaucomatous eyes with high-intraocular pressure can show a strikingly similar appearance of the optic nerve head, including a loss of neuroretinal rim, a deepening of the optic cup, and an enlargement of parapapillary atrophy. These features, however, are not found in any (other) vascula...

2011-01-01

202

Residual limb osteomyelitis: A case series from a national prosthetic centre  

British Library Electronic Table of Contents (United Kingdom)

Purpose. To examine the impact of residual limb osteomyelitis (RLO) on the rehabilitation of lower limb amputees. Method. Retrospective review of the casenotes of patients with RLO. Information sought included details of amputation, clinical features of investigations for and management of RLO and its effect on rehabilitation. Results. There were seven transfemoral and three transtibial amputees. Indications for amputation were vascular disease in nine cases, trauma in one. In each case, delayed wound healing or residual limb pain prompted radiological, hematological and microbiological investigations. Average time between amputation and diagnosis was 187 days. One patient died before treatment commenced. Two transtibial amputees were treated with intravenous antibiotics while rehabilitati...

2009-01-01

203

Radiation-induced large intracranial vessel occlusive vasculopathy.  

Science.gov (United States)

Two patients who developed large intracranial vessel occlusion after standard radiation therapy for brain tumor are described. This form of vascular occlusion is usually seen in patients who have previously been treated by radiotherapy for intracranial tumor who then develop a relatively acute change in neurologic status. Histology of the lesion mimics accelerated focal arteriosclerosis. The clinical and radiographic manifestations of one case were highly atypical. The vasculopathy became evident shortly after termination of radiation therapy for a fourth ventricular ependymoma, and the angiographic picture stimulated a diffuse arteritis. The second patient was more typical, with clinical symptoms developing 12 years after radiation therapy for an oligodendroglioma. Occlusion of a proximal vessel that had been included in the radiation port was demonstrated radiographically and confirmed by pathologic examination. The clinical, angiographic, and histologic features ...

1980-01-01

204

Radiation-induced large intracranial vessel occlusive vasculopathy  

Energy Technology Data Exchange (ETDEWEB)

Two patients who developed large intracranial vessel occlusion after standard radiation therapy for brain tumor are described. This form of vascular occlusion is usually seen in patients who have previously been treated by radiotherapy for intracranial tumor who then develop a relatively acute change in neurologic status. Histology of the lesion mimics accelerated focal arteriosclerosis. The clinical and radiographic manifestations of one case were highly atypical. The vasculopathy became evident shortly after termination of radiation therapy for a fourth ventricular ependymoma, and the angiographic picture stimulated a diffuse arteritis. The second patient was more typical, with clinical symptoms developing 12 years after radiation therapy for an oligodendroglioma. Occlusion of a proximal vessel that had been included in the radiation port was demonstrated radiographically and confirmed by pathologic examination. The clinical, angiographic, and histologic features ...

1980-01-01

205

Pigpen, a nuclear coiled body component protein, is involved in angiogenesis  

British Library Electronic Table of Contents (United Kingdom)

We previously reported that puromycin-insensitive leucyl-specific aminopeptidase (PILSAP) is required for vascular endothelial growth factor (VEGF)- and basic fibroblast growth factor (bFGF)-induced angiogenesis and for endothelial differentiation from embryonic stem (ES) cells via the aminopeptidase activity of PILSAP. In this study, we searched for molecules that function during angiogenesis with PILSAP. We performed proteome analysis of nuclear extracts from embryoid bodies (EBs) made from ES cells transfected with mutant PILSAP lacking aminopeptidase activity and mock EBs. We identified pigpen, a 67-kDa nuclear coiled body component protein. Immunoprecipitation and western blotting demonstrated the binding of PILSAP and pigpen in endothelial cells (ECs), and this interaction was enhanc...

2010-01-01

206

Outcome of peripherally inserted central venous catheters in surgical and medical neonates  

British Library Electronic Table of Contents (United Kingdom)

Background/Purpose: Peripherally inserted central venous catheters (PICCs) are commonly used for neonatal vascular access. The aim of this study was to look at PICC line complication rates and possible predictors of PICC infection in a neonatal intensive care unit. Method: This was a prospective study of 226 neonates who had PICCs on our neonatal intensive care unit between January 2006 and June 2009. Complete data was available on 218 neonates who had 294 PICC lines. Criteria for catheter-related sepsis was positive blood cultures (peripheral/central) and/or a positive catheter tip culture after removal in the presence of a clinical suspicion of line sepsis. Results: Of 218 neonates, 132 (169 lines) were medical, and 86 (125 lines) were surgical. Our PICC line infection rate was 17 infect...

2011-01-01

207

Multidetector Computed Tomography in the Preoperative Workup of Hilar Cholangiocarcinoma  

International Nuclear Information System (INIS)

Hilar cholangiocarcinoma is associated with a dismal prognosis; however, curative resection may offer a chance of cure. Various factors should be considered in the surgical planning for curative resection. These factors include extent of bile duct involvement, relationship between portal vein and tumor involvement, diffuse hepato duodenal ligament infiltration, vascular invasion, lymph node metastasis, peritoneal seeding, and hepatic volume. Using high-quality volume data from multidetector-row computed tomography (MDCT) and adequate postprocessing images, radiologists can provide various types of information, imperative for curative resection of a hilar cholangiocarcinoma. This review illustrates the role of MDCT in the preoperative workup of hilar cholangiocarcinoma.

2009-10-01

208

Intermediate-conductance calcium-activated potassium channels participate in neurovascular coupling  

British Library Electronic Table of Contents (United Kingdom)

BACKGROUND AND PURPOSE Controlling vascular tone involves K+ efflux through endothelial cell small- and intermediate-conductance calcium-activated potassium channels (KCa2.3 and KCa3.1, respectively). We investigated the expression of these channels in astrocytes and the possibility that, by a similar mechanism, they might contribute to neurovascular coupling. EXPERIMENTAL APPROACH Transgenic mice expressing enhanced green fluorescent protein (eGFP) in astrocytes were used to assess KCa2.3 and KCa3.1 expression by immunohistochemistry and RT-PCR. KCa currents in eGFP-positive astrocytes were determined in situ using whole-cell patch clamp electrophysiology. The contribution of KCa3.1 to neurovascular coupling was investigated in pharmacological experiments using electrical field stimulatio...

2011-01-01

209

In vivo chicken model for peripheral intravascular human fibrin clot detection  

Energy Technology Data Exchange (ETDEWEB)

A chicken model was prepared that provides a simple and economical method of evaluating the use of fibrin-specific monoclonal antibody 64C5 in the detection of peripheral vascular thrombi. Human fibrin was clotted in segments of a chicken's femoral artery and vein prior to intravenous injection of radioiodinated antibody 64C5. After a 3-hr perfusion time, the thrombosed and contralateral control segments of the vessels were excised and counted for radioactivity. The radiolabeled 64C5 uptake ratio of the thrombosed segment to the control segment was 5.4 +/- 1.2 (p less than 0.007) in the femoral artery, and 3.8 +/- 1.1 (p less than 0.02) in the femoral vein. This in vivo chicken model may also find application in studies of targeting agents for human fibrin.

1988-08-01

210

In vitro and in vivo evaluation of [{sup 123}I]-VEGF{sub 165} as a potential tumor marker  

Energy Technology Data Exchange (ETDEWEB)

One of the research challenges in oncology is to develop new biochemical methods for noninvasive tumor therapy evaluation to determine whether the chemotherapeutics is effective. Vascular endothelial growth factor (VEGF) was labeled with radioiodine and evaluated in vitro as well as in vivo, using A2058, a melanoma cell line overexpressing VEGFR-1 and -2. Saturation binding analysis with [{sup 125}I]-VEGF resulted in a K {sub d} of 0.1 nM. Internalization assays indicate the preserved ligand induced internalization and metabolization of the tracer. Biodistribution studies with [{sup 123}I]-VEGF in wild type and A2058 tumor-bearing athymic mice showed low background activity and a tumor to reference tissue ratio of maximum 6.12. These results suggest that [{sup 123}I]-VEGF is a potentially suitable tracer for tumor therapy evaluation.

2005-07-01

211

Forkhead box protein P1 as a downstream target of transforming growth factor-b induces collagen synthesis and correlates with a more stable plaque phenotype  

British Library Electronic Table of Contents (United Kingdom)

Objective: Atherosclerosis is an inflammatory disease, modulated by plaque stabilizing and de-stabilizing cell populations such as infiltrating monocytes and vascular smooth muscle cells (vSMCs). Transcription factors regulating proliferation and differentiation of atherosclerosis relevant cell types are of interest in this context. The forkhead box transcription factor FoxP1 modulates monocyte differentiation. We studied FoxP1 expression in atherosclerotic tissue, correlated FoxP1 expression with plaque characteristics and identified associations between FoxP1 and plaque proteins. Methods: 116 Atherosclerotic plaques from carotid endarterectomy samples were histologically classified (fibrous, fibroatheromatous, atheromatous) and subjected to semi-quantitative protein analysis. Macrophage,...

2011-01-01

212

Efficient elimination of sweetpotato little leaf phytoplasma from sweetpotato by cryotherapy of shoot tips  

British Library Electronic Table of Contents (United Kingdom)

Shoot tips with 3-4 leaf primordia were excised from in vitro-grown sweetpotato plants (Ipomoea batatas) infected with little leaf phytoplasma (Candidatus Phytoplasma aurantifolia) and subjected to cryotherapy. All plants regenerated from the cryo-treated shoot tips were free of phytoplasma, whereas shoot tip culture or dehydration of shoot tips without subsequent cryotherapy resulted in phytoplasma-free plants at a frequency of only 7-10%. Histological and ultrastructural studies with light and transmission electron microscopy, respectively, indicated that cryotherapy was lethal to all cells except those in the apical dome of the meristem and the two youngest leaf primordia. These surviving parts of the shoot tip contained vascular tissue and sieve elements, but electron microscopy showed...

2008-01-01

213

Effect of postharvest water deficit stress on gene expression in heads of broccoli (Brassica oleracea var. italica)  

British Library Electronic Table of Contents (United Kingdom)

Harvested plant organs such as heads of broccoli (Brassica oleracea L. var. italica) experience a range of stresses that can lead to premature reduction in quality and eventual senescence. Understanding plant responses to stress may open up novel opportunities to extend postharvest life. One of the first stresses experienced by harvested organs is likely to be water deficit stress since severance of the vascular system halts the normal flux of water into the tissue. For broccoli branchlets with their cut ends held in water, transcriptome analysis based on hybridization of broccoli floret mRNA to a heterologous Arabidopsis microarray revealed that the transcript abundance of 431 genes reliably changed within 48h of harvest. Of these, transcripts of 146 genes increased and 34 genes decreased...

2011-01-01

214

Effect of Tong Luo Jiu Nao on Ab-degrading enzymes in AD rat brains  

British Library Electronic Table of Contents (United Kingdom)

Ethnopharmacological relevance: Tong Luo Jiu Nao (TLJN) is a modern Chinese formula based on Traditional Chinese Medicine theory that has been used to treat ischemic cerebral stroke and vascular dementia. TLJN belongs to the ethnopharmacological family of medicines. In this study, we investigated the mechanism of the TLJN effect on Alzheimer's disease (AD). Aim of the study: To investigate the effect of TLJN on b-amyloid-degrading enzymes and learning and memory in the AD rat brain. Materials and methods: AD rats whose disease was induced by Ab25-35 injection into the bilateral hippocampus CA1 region were subjected to intragastric administration of various preparations. The experimental animals were healthy male Sprague-Dawley rats which were randomly divided into normal, sham, model, TLJN...

2011-01-01

215

Comparison of skeletal and bone marrow radionuclide scintimetry of femoral neck fracture  

Energy Technology Data Exchange (ETDEWEB)

Twenty-six patients with late complications following femoral neck fracture were examined with both skeletal and bone marrow radionuclide scintimetry. There was no correlation between the methods with respect to the quantitative assessment of femoral head vascularity based on different uptake ratios comparing the fractured and the intact side. Skeletal scintimetry always had good image quality and permitted reliable differentation between nonunion of the fracture and late segmental collapse, in contrast to bone marrow scintimetry which gave poor image quality. Skeletal scintimetry thus seems superior to bone marrow scintimetry for assessment and differential diagnosis of late complications following femoral neck fracture. It is emphasized that the physiological mechanisms for radionuclide uptake must be taken into account when comparing scintimetric studies using different tracers.

1984-01-01

216

Comparison of skeletal and bone marrow radionuclide scintimetry of femoral neck fracture  

International Nuclear Information System (INIS)

Twenty-six patients with late complications following femoral neck fracture were examined with both skeletal and bone marrow radionuclide scintimetry. There was no correlation between the methods with respect to the quantitative assessment of femoral head vascularity based on different uptake ratios comparing the fractured and the intact side. Skeletal scintimetry always had good image quality and permitted reliable differentation between nonunion of the fracture and late segmental collapse, in contrast to bone marrow scintimetry which gave poor image quality. Skeletal scintimetry thus seems superior to bone marrow scintimetry for assessment and differential diagnosis of late complications following femoral neck fracture. It is emphasized that the physiological mechanisms for radionuclide uptake must be taken into account when comparing scintimetric studies using different tracers. (author).

217

CF findings of bowel infarction in 56 surgical patients, 5 of whom with reversible ischemia  

International Nuclear Information System (INIS)

Bowel infarction is a rare and typical condition of the elderly; despite improvements in diagnostic imaging and vascular surgery, bowel infarction remains a major cause of acute abdomen, with mortality rates ranging 70-80%. Diagnosis on often late because clinical sings, laboratory data and radiologic findings are a specific. The authors investigated radiographic and particular CT patterns of intestinal infraction in 56 patients submitted to surgery within 12 hours of admission. We also report the CT findings of 5 of these patients who had reversible mesenteric ischemia. CT is more sensitive than radiography and does not exhibit the limitations of angiography (i.e., invasiveness, radiation exposure an complex organization. Therefore CT can presently be considered the method of choice in patients with suspected bowel infarction.

1999-04-01

218

Bilateral brachial pull-through technique for stenting in a patient with stenosis of the vertebral artery origin: technical case report  

International Nuclear Information System (INIS)

Stenting for stenosis of the proximal vertebral artery (VA) is commonly performed via a femoral approach. However, iliofemoral occlusive disease such as arteriosclerosis obliterans sometimes prevents safe transfemoral access. In certain situations where both femoral access and ipsilateral brachial access are difficult because of a concomitant vascular diseases or particular anatomic setting, a contralateral brachial approach using the brachiobrachial pull-through technique may allow efficient and accurate stenting. A case of VA origin symptomatic stenosis successfully treated with stenting using the new pull-through technique from the contralateral brachial artery to the brachial artery on the affected side is described. (orig.)

2007-10-01

219

A method of stereotaxic localization adopted for conventional and digital radiography  

International Nuclear Information System (INIS)

A method for the determination of stereotaxic coordinates in radiography, e.g. angiography, pneumoencephalography or digital vascular radiography, is described. A special localization frame containing radiopaque structures and scales defines a diagnostic coordinate system. This frame is fixed to the X-ray-table prior to the radiographic procedure and two projections are obtained at arbitrary angles to each other. The focus-film distances do not have to be fixed. The target coordinates are then determined either by a simple graphical procedure or with the use of a digitizing x-y-table, by a computer. With the computer method the films are placed on the digitizing table and the target and a few reference points are marked using a cursor. From the relative positions the computer calculates the coordinates. With the special head fixation system, coordinates of structures visualized in radiographic examinations can be transferred to various therapeutic or diagnostic ...

1986-01-01

220

The application of 64 multidetector CT angiography in the evaluation of carotid stenosis and follow-up of carotid endarterectomy and percutaneous transluminal stenting  

International Nuclear Information System (INIS)

Objective: To evaluate the diagnostic value of 64 multidetector-row CT angiography for internal carotid artery (ICA) stenosis and the application in the follow-up of carotid endarterectomy and percutaneous transluminal stenting. Methods: Forty transient ischemic attack (TIA) patients with interpretable CTA and DSA of the cervical carotid arteries were selected from May 2005 to December 2005. This yielded a total of 80 vessels. The CTA curved planar reformations (CPR) and DSA images referenced to the distal cervical internal carotid were graded by two senior neuroradiologists blindly, according to the North American Symptomatic Carotid Endarterectomy Trial (NASCET) guidelines. The paired-t test was used to verify the statistical significant difference between pre-operating and post-operating of carotid endarterectomy or percutaneous transluminal stenting in measuring the vascular diameter and area of cross section using CTA. Results: When the 70% stenosis was used ...

2006-09-01

221

Short-term inhibition of ADP-induced platelet aggregation by clopidogrel ameliorates radiation-induced toxicity in rat small intestine.  

Science.gov (United States)

Endothelial dysfunction and increased platelet aggregation may be involved in the pathogenesis of normal tissue radiation toxicity. This study assessed clopidogrel, an inhibitor of ADP-induced platelet aggregation, as a modulator of intestinal radiation injury (radiation enteropathy). Rat small intestine was exposed to 21 Gy X-radiation. Clopidogrel (20 mg/kg/day) or vehicle was administered from 2 days before to 10 days after irradiation. Structural radiation injury, neutrophil infiltration, smooth muscle cell proliferation, collagen content, and TGF-beta1 expression were assessed 2 weeks (early phase) and 26 weeks (delayed phase) after irradiation, using quantitative histology and immunohistochemistry, morphometry, and real-time fluorogenic probe RT-PCR. Irradiated intestine exhibited significant histopathologic injury, reduced mucosal surface area, vascular sclerosis, intestinal wall fibrosis, increased collagen content, and increased TGF-beta1 expression. ...

2002-01-01

222

Rapid inhibition of vasoconstriction in renal afferent arterioles by aldosterone  

DEFF Research Database (Denmark)

Aldosterone has been suggested to elicit vessel contraction via a nongenomic mechanism. We tested this proposal in microdissected, perfused rabbit renal afferent arterioles. Aldosterone had no effect on internal diameter in concentrations from 10(-10) to 10(-5) mol/L, but aldosterone abolished the ability of 100 mmol/L KCl to induce vascular contraction. The inhibitory effect of aldosterone was observed from 1 pmol/L. The inhibitory effect was significant after 5 minutes and maximal after 20 minutes and was fully reversible. Actinomycin D (10(-6) mol/L) prolonged the effect of aldosterone. The effect was abolished by the mineralocorticoid receptor antagonist spironolactone (10(-7) mol/L) but not by the glucocorticoid receptor antagonist mifepristone (10(-6) mol/L). The K+-mediated increase of intracellular calcium concentration in afferent arterioles was not affected by aldosterone. Mineralocorticoid receptor was detected by reverse transcription-polymerase chain ...

2003-01-01

223

Proteomic Profiling of Mesenchymal Stem Cell Responses to Mechanical Strain and TGF-B1  

Energy Technology Data Exchange (ETDEWEB)

Mesenchymal stem cells (MSCs) are a potential source of smooth muscle cells (SMCs) for constructing tissue-engineered vascular grafts. However, the details of how specific combinations of vascular microenvironmental factors regulate MSCs are not well understood. Previous studies have suggested that both mechanical stimulation with uniaxial cyclic strain and chemical stimulation with transforming growth factor {beta}1 (TGF-{beta}1) can induce smooth muscle markers in MSCs. In this study, we investigated the combined effects of uniaxial cyclic strain and TGF-{beta}1 stimulation on MSCs. By using a proteomic analysis, we found differential regulation of several proteins and genes, such as the up-regulation of TGF-{beta}1-induced protein ig-h3 (BGH3) protein levels by TGF-{beta}1 and up-regulation of calponin 3 protein level by cyclic strain. At the gene expression level, BGH3 was induced by TGF-{beta}1, but calponin 3 was not significantly ...

2009-10-12

224

Patterns of vascular invasion of intrahepatic peripheral cholangiocarcinoma examined with angiography and angiographic CT  

International Nuclear Information System (INIS)

To evaluate the radiological patterns of vascular invasion in peripheral cholangiocarcinomas. Hepatic arteriography and portography in 20 cases with cholangiocarcinoma including 12 cases with angiographic CT were retrospectively analyzed. The arteriography showed no arterioportal shunt, hypertrophy of tumor vessel, or tumor staining extending to central portion of the mass in all cases. However, doughnut shaped peripheral tumor staining was seen until late hepatogram phase in 12 cases and compensatory hyperperfusion around the mass was seen in six cases (eight cases if include arterial CT). Encasement of tumor vessel was seen in 12 cases, and hypertrophy of feeding vessel in nine cases. On portography, the filling defect on segmental portal branch could be demonstrated only in 11 cases. Shape of the portal defect was tapered narrowing in six cases, abrupt narrowing in two cases but intraluminal nodular filling defect was not seen. Remaining three cases were ...

1995-01-01

225

Intestinal circulation during inhalation anesthesia  

Energy Technology Data Exchange (ETDEWEB)

This study was designed to evaluate the influence of inhalational agents on the intestinal circulation in an isolated loop preparation. Sixty dogs were studied, using three intestinal segments from each dog. Selected intestinal segments were pumped with aortic blood at a constant pressure of 100 mmHg. A mixture of /sub 86/Rb and 9-microns spheres labeled with /sup 141/Ce was injected into the arterial cannula supplying the intestinal loop, while mesenteric venous blood was collected for activity counting. A very strong and significant correlation was found between rubidium clearance and microsphere entrapment (r = 0.97, P less than 0.0001). Nitrous oxide anesthesia was accompanied by a higher vascular resistance (VR), lower flow (F), rubidium clearance (Cl-Rb), and microspheres entrapment (Cl-Sph) than pentobarbital anesthesia, indicating that the vascular bed in the intestinal segment was constricted and flow (total and nutritive) decreased. ...

1985-04-01

226

Intestinal circulation during inhalation anesthesia  

International Nuclear Information System (INIS)

This study was designed to evaluate the influence of inhalational agents on the intestinal circulation in an isolated loop preparation. Sixty dogs were studied, using three intestinal segments from each dog. Selected intestinal segments were pumped with aortic blood at a constant pressure of 100 mmHg. A mixture of _8_6Rb and 9-microns spheres labeled with "1"4"1Ce was injected into the arterial cannula supplying the intestinal loop, while mesenteric venous blood was collected for activity counting. A very strong and significant correlation was found between rubidium clearance and microsphere entrapment (r = 0.97, P less than 0.0001). Nitrous oxide anesthesia was accompanied by a higher vascular resistance (VR), lower flow (F), rubidium clearance (Cl-Rb), and microspheres entrapment (Cl-Sph) than pentobarbital anesthesia, indicating that the vascular bed in the intestinal segment was constricted and flow (total and nutritive) decreased. ...

227

Importance of the planning activities, cutting, handling and analysis of the nuclei of oil well drilling; Importancia de las actividades de planificacion, corte, manejo y analisis de los nucleos de perforacion de pozos petroleros  

Energy Technology Data Exchange (ETDEWEB)

In the geologic formation where the oil deposits are located, diverse types of rocks perform functions as structural elements, storage containers for hydrocarbon water and calorific energy, as well as impermeable barriers and transport means of the energy and the fluids. Among the most important properties that are used to describe these functions are the porosity, the permeability, the compressibility of the pores volume, the formation resistivity factor, the saturation exponent, the velocity of acoustic waves P and S, the relative permeability, the capillary pressures, the elastic constants and other mechanical properties, the thermal expansion, coefficient, the thermal conductivity, the thermal diffusivity and the specific heat. The execution of an ample variety of activities related to the stages of exploration, location, evaluation and development of the oil deposits, depends strongly on having a good knowledge of the magnitude and the spatial variability of these properties. The ...

2007-07-01

228

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

Energy Technology Data Exchange (ETDEWEB)

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 ...

1985-02-15

229

[Natriuretic peptides--relevance in intensive care].  

Science.gov (United States)

The family of natriuretic peptides consists of the atria natriuretic peptide (ANP), the cerebral natriuretic peptide (BNP), the type C natriuretic peptide (CNP) and the peptide isolated from the dendroaspis snakes' poison (DNP), whose presence in humans has not been confirmed. The physiological function of ANP is in the control of arterial blood pressure by regulation of systemic vascular resistance of blood vessels. BNP is produced as one of the factors in the acute response to inflammatory tissue damage, mainly in coronary vessels. Increased serum concentrations of natriuretic peptides have been found in stress situations, such as trauma or major surgery, systemic hypotension, and in intrinsic myocardial dysfunction. High concentrations of natriuretic peptides were observed in severe sepsis, septic shock and in multiple organ failure, probably due to increased secretion by mediators of the inflammatory process.The highest concentrations of ANP and BNP were found ...

230

Treatment of proliferative haemangiomas with the 585 nm pulsed dye laser.  

Science.gov (United States)

Haemangiomas usually develop within the first few weeks of life, most regressing spontaneously before the age of 7 years. Some may ulcerate or compromise a vital function, in which case systemic corticosteroids, surgery or radiotherapy may be helpful. All of these treatment modalities are associated with significant morbidity. Treatment with the 585 nm flashlamp pulsed dye laser is safe and effective in the management of superficial vascular malformations. We report seven patients, under 12 months of age, who presented with proliferative haemangiomas, causing functional impairment. Ulcerated lesions were present in four patients. The patients were treated with the 585 nm pulsed dye laser (fluences 7.0-9.25 J/cm2), at intervals of 4-8 weeks. All of the lesions showed a significant reduction in size, together with improvement in the colour and integrity of the overlying skin. Treatment with the 585 nm pulsed dye laser should be considered in the management of infants ...

1996-04-01

231

The treatment of chronic pain by epidural spinal cord stimulation--a 15 year follow up; present status.  

Science.gov (United States)

Pain is necessary for survival but chronic pain is disabling and causes significant health and economic problems. This study provides an understanding of the future for spinal cord stimulation. Stimulation by means of chronically implanted electrodes, was carried out in 200 patients with pain of varied benign organic etiology. In 177 of them, pain was confined to the failed back syndrome. Most patients were referred by a Pain Management Service. 226 epidural implants were used: 80 unipolar, 59 Resume, 12 bipolar, and 75 quadripolar. Patients were followed for periods of 6 months to 12 years, with a mean follow-up of 44 months. 84 patients (42%) were able to control their pain by stimulation alone, 22 patients (11%) needed occasional analgesic supplements along with their stimulation program. Pain secondary to failed back syndrome, multiple sclerosis, peripheral vascular disease, sympathetic dystrophy and diabetic neuropathy responded favorably. Pain due to cauda ...

1997-06-01

232

The neuroimmune-endocrine axis: pathophysiological implications for the central nervous system cytokines and hypothalamus-pituitary-adrenal hormone dynamics  

Scientific Electronic Library Online (English)

Abstract in english Cytokines are molecules that were initially discovered in the immune system as mediators of communication between various types of immune cells. However, it soon became evident that cytokines exert profound effects on key functions of the central nervous system, such as food intake, fever, neuroendocrine regulation, long-term potentiation, and behavior. In the 80's and 90's our group and others discovered that the genes encoding various cytokines and their receptors are e (more) xpressed in vascular, glial, and neuronal structures of the adult brain. Most cytokines act through cell surface receptors that have one transmembrane domain and which transduce a signal through the JAK/STAT pathway. Of particular physiological and pathophysiological relevance is the fact that cytokines are potent regulators of hypothalamic neuropeptidergic systems that maintain neuroendocrine homeostasis and which regulate the body's response to stress. The mechanisms ...

2000-10-01

233

The angiogram sign in pulmonary atelectasis studied with helical Computed Tomography. Incidence and value; Il segno dell'angiogramma nelle atelettasie polmonari studiate con Tomografia Computerizzata spirale. Incidenza e validita' semeiologica  

Energy Technology Data Exchange (ETDEWEB)

In this issue it has been investigated the yield of Helical CT in the study of lung vessels, the incidence of the angiogram sign and its actual value. July 1997 to December 1998, were studied 30 cases of pulmonary collapse of different origin. It was found 15 cases of passive collapse (10 from pleural effusion, 2 from diaphragmatic compression, 2 from traumatic pneumothorax, and 1 from isthmic aortic aneurysm), 12 cases of obstructive collapse (9 from bronchogenic carcinoma, 1 from mucoid obstruction, 1 from ilar lymphadenopathy, and 1 from mediastinal cancer), 2 cases of adhesive collapse and 1 case of round atelectasis. All the examinations were performed with the Helical technique during nonionic iodinated contrast agent injection (bolus, 300-350 mg/mL); it was used an automatic injector set at 2-3 mL/s. It was studied the images for the angiogram sign, that is hyperdense bands, usually longer than 2 cm, through the collapsed lung, which correspond to normal pulmonary ...

1999-12-01

234

The SPIRIT V Study:A Clinical Evaluation of the XIENCE V Everolimus-Eluting Coronary Stent System in the Treatment of Patients With De Novo Coronary Artery Lesions  

British Library Electronic Table of Contents (United Kingdom)

ObjectivesThe SPIRIT V (A Clinical Evaluation of the XIENCE V Everolimus-Eluting Coronary Stent System in the Treatment of Patients With De Novo Coronary Artery Lesions) study is a post-market surveillance experience of the XIENCE V (Abbott Vascular, Santa Clara, California) everolimus-eluting stent (EES) in patients with higher-risk coronary anatomy. BackgroundPrevious pre-approval studies have shown the safety and efficacy of EES in highly selected groups of patients. MethodsThe SPIRIT V trial is a prospective, open label, single arm, multicenter study. Two thousand seven hundred patients with multiple de novo coronary artery lesions suitable for treatment with a planned maximum of 4 EES were enrolled at 93 centers in Europe, Asia Pacific, Canada, and South Africa. Lesions had a referenc...

2011-01-01

235

Selective absorption of ultraviolet laser energy by human atherosclerotic plaque treated with tetracycline  

Energy Technology Data Exchange (ETDEWEB)

Tetracycline is an antibiotic that absorbs ultraviolet light at 355 nm and preferentially binds to atherosclerotic plaque both in vitro and in vivo. Tetracycline-treated human cadaveric aorta was compared with untreated aorta using several techniques: absorptive spectrophotometry; and tissue uptake of radiolabeled tetracycline, which showed 4-fold greater uptake by atheroma than by normal vessel. In addition, intravenous tetracycline administered to patients undergoing vascular surgery demonstrated characteristic fluorescence in surgically excised diseased arteries. Because of tetracycline's unique properties, the authors exposed tetracycline-treated and untreated aorta to ultraviolet laser radiation at a wavelength of 355 nm. They found enhanced ablation of tetracycline-treated atheroma compared with untreated atheroma. The plaque ablation caused by ultraviolet laser radiation was twice as extensive in tetracycline-treated vs nontreated plaque. This study ...

1985-05-01

236

Salicylate Treatment Improves Age-Associated Vascular Endothelial Dysfunction: Potential Role of Nuclear Factor kB and Forkhead Box O Phosphorylation  

British Library Electronic Table of Contents (United Kingdom)

We hypothesized that I kappa B kinase (IKK)-mediated nuclear factor kappa B and forkhead BoxO3a phosphorylation will be associated with age-related endothelial dysfunction. Endothelium-dependent dilation and aortic protein expression/phosphorylation were determined in young and old male B6D2F1 mice and old mice treated with the IKK inhibitor, salicylate. IKK activation was greater in old mice and was associated with greater nitrotyrosine and cytokines. Endothelium-dependent dilation, nitric oxide (NO), and endothelial NO synthase phosphorylation were lower in old mice. Endothelium-dependent dilation and NO bioavailability were restored by a superoxide dismutase mimetic. Nuclear factor kappa B and forkhead BoxO3a phosphorylation were greater in old and were associated with increased express...

2011-01-01

237

Retrieval of intravascular foreign bodies with goose neck snare  

Energy Technology Data Exchange (ETDEWEB)

Purpose: to evaluate the efficacy and advantages of the snare systems in the retrieval of foreign bodies from vascular system. Materials and methods: the snare technique has been used for intravascular foreign body retrieval. We performed percutaneous extraction of intravascular foreign bodies using combination multipurpose catheters and a nitinol snare loop. In this report, we evaluated the patients who had performed endovascular device reposition or foreign body retrieval from 1998 to 2001. Results: foreign body retrieval was performed in 15 patients. The foreign bodies consisted of seven fractured port catheters, one sheath fragment, one embolization coil, four wire fragments, one pace-maker transducer and one dislocated endovascular stent. In no case were surgical procedures required, and no complications were encountered. Conclusion: the snare technique is a useful and a safe method as an alternative procedure to surgery. This technique is highly effective ...

2004-03-01

238

Repair of the radiation induced rectovaginal fistulas without or with interposition of the bulbocavernosus muscle (Martius procedure)  

Energy Technology Data Exchange (ETDEWEB)

Two local repair procedures, one without (9) and the other with (14) a bulbocavernosus muscle graft were performed on 20 patients with a radiation induced rectovaginal fistula. Four patients had two procedures successively. The initial success rate of both procedures was 7/9 and 14/14 respectively. Though the initial result of the bulbocavernosus graft was obviously better, in many of the local repair procedures, subclinical radiation damage progressed, resulting in recurrence of rectovaginal fistula (5), rectovesical fistula (4), pararectal abscess (2) etc. After a mean follow up of around 10 years, the success rate of fistula repair decreased to 5/9 and 13/14 and only 2/9 and 6/14 finally remained without a colostomy. A local repair operation should be restricted to carefully selected cases. The musculus gracilis is proposed as a better vascular graft. If the general condition of the patient does not allow more aggressive reconstructive procedures, fistula repair ...

1988-04-01

239

Reconstructive surgery for the complications of pelvic irradiation  

Energy Technology Data Exchange (ETDEWEB)

Severe damage to the pelvic viscera is a complication of irradiation therapy that, unfortunately, cannot always be avoided. Resulting rectal and rectocolonic strictures, rectovaginal fistulas, and shortening and stenosis of the vagina present very difficult problems that frequently require a colostomy for relief and may permanently impair sexual function. The authors present a new approach to correction of these unfortunate lesions based on the use of proximal nonirradiated colon which serves as a vascular pedicle graft to correct the defect without a complicated and massive resection. Twenty-two such operations have been done with 19 satisfactory to excellent results and two total failures (one death from small bowel complications). All patterns and combinations of irradiation injury have been found amenable to this technique of repair. These have included both web and linear strictures with and without fistulas. In half of the patients, it was possible to make ...

1984-02-01

240

Radiant{trademark} Liquid Radioisotope Intravascular Radiation Therapy System  

Energy Technology Data Exchange (ETDEWEB)

RADIANT{trademark} is manufactured by United States Surgical Corporation, Vascular Therapies Division, (formerly Progressive Angioplasty Systems). The system comprises a liquid {beta}-radiation source, a shielded isolation/transfer device (ISAT), modified over-the-wire or rapid exchange delivery balloons, and accessory kits. The liquid {beta}-source is Rhenium-188 in the form of sodium perrhenate (NaReO{sub 4}), Rhenium-188 is primarily a {beta}-emitter with a physical half-life of 17.0 hours. The maximum energy of the {beta}-particles is 2.1 MeV. The source is produced daily in the nuclear pharmacy hot lab by eluting a Tungsten-188/Rhenium-188 generator manufactured by Oak Ridge National Laboratory (ORNL). Using anion exchange columns and Millipore filters the effluent is concentrated to approximately 100 mCi/ml, calibrated, and loaded into the (ISAT) which is subsequently transported to the cardiac catheterization laboratory. The delivery catheters are modified ...

1998-01-16

241

Partitioning and transport of the translocates mannitol and sucrose in the light and dark in celery (Apium Graveolens L. )  

Energy Technology Data Exchange (ETDEWEB)

Sucrose and mannitol are major photosynthetic products and translocates in celery. Assimilate partitioning and transport were studied by pulse-labeling leaves with /sup 14/CO/sub 2/ followed by different length chases in ambient air. After a 2 h chase in the light there was more /sup 14/C in sucrose than mannitol in source leaves and their petioles. In contrast after a 2 h dark chase leaves contained more /sup 14/C in mannitol than sucrose but petioles had more /sup 14/C in sucrose than mannitol. After a 15 h chase (6 h light; 9 h dark) labeled sucrose was higher in source petiole vascular bundles than in adjacent parenchyma tissue but label in glucose and fructose was higher in the parenchyma tissue. After the 15 h chase most of the /sup 14/C remaining in developing sink leaves and their petioles was in mannitol. Although in the light mannitol:sucrose ratios are the same in leaf and petiole tissues, in the dark sucrose is initially the major translocate with ...

1987-04-01

242

Natriuretic peptides in the pathophysiology of congestive heart failure.  

Science.gov (United States)

A hallmark of congestive heart failure (CHF) is the activation of the cardiac endocrine system, in particular atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP). The natriuretic peptides are a group of structurally similar but genetically distinct peptides that have diverse actions in cardiovascular, renal, and endocrine homeostasis. ANP and BNP are of myocardial cell origin and C-type natriuretic peptide (CNP) is of endothelial origin. ANP and BNP bind to the natriuretic peptide-A receptor (NPR-A), which, via 3',5'-cyclic guanosine monophosphate (cGMP), mediates natriuresis, vasodilatation, renin inhibition, antimitogenesis, and lusitropic properties. CNP lacks natriuretic actions but possesses vasodilating and growth inhibiting actions via the guanylyl cyclase-linked natriuretic peptide-B receptor. All three peptides are cleared by the natriuretic peptide-C receptor and degraded by the ectoenzyme neutral endopeptidase 24.11, both of which are widely expressed in ...

2000-05-01

243

Methodological study of hemodynamic analysis of lung mass by contrast enhanced dynamic CT  

Energy Technology Data Exchange (ETDEWEB)

We investigated a method of analyzing the hemodynamics of the lung mass by contrast enhanced dynamic computed tomography (dynamic CT) to determine the difference in vascular supply between the pulmonary artery and bronchial artery using an experimental model. Our experimental model consisted of two injectors connected to two tubes, representing the pulmonary artery and bronchial artery, which were further connected to a chamber representing the lung mass. Following infusion of contrast medium into each tube with some delay time, dynamic CT scans were performed to obtain time density curves of the two tubes and the chamber. Using the time-density curve of contrast passage, flow rates from the two tubes into the chamber were calculated by the curve fitting method. Calculated values correlated well with the adopted flow rates of fluid from the injectors (r=0.893) in the experiment. The results indicate our method of individually measuring flow rates of dual-input ...

1996-06-01

244

Methodological study of hemodynamic analysis of lung mass by contrast enhanced dynamic CT  

International Nuclear Information System (INIS)

We investigated a method of analyzing the hemodynamics of the lung mass by contrast enhanced dynamic computed tomography (dynamic CT) to determine the difference in vascular supply between the pulmonary artery and bronchial artery using an experimental model. Our experimental model consisted of two injectors connected to two tubes, representing the pulmonary artery and bronchial artery, which were further connected to a chamber representing the lung mass. Following infusion of contrast medium into each tube with some delay time, dynamic CT scans were performed to obtain time density curves of the two tubes and the chamber. Using the time-density curve of contrast passage, flow rates from the two tubes into the chamber were calculated by the curve fitting method. Calculated values correlated well with the adopted flow rates of fluid from the injectors (r=0.893) in the experiment. The results indicate our method of individually measuring flow rates of dual-input ...

245

Lipiodol-CT in the detection of tumor persistence in hepatocellular carcinoma treated with percutaneous ethanol injection  

Energy Technology Data Exchange (ETDEWEB)

Our purpose was to investigate the usefulness of Lipiodol-CT for detection of residual viable neoplastic tissue in hepatocellular carcinoma (HCC) lesions treated by means of percutaneous ethanol injection (PEI). An emulsion of 5 to 20 ml iodized oil and 50 to 70 mg doxorubicin hydrochloride was intraarterially injected in 18 patients with 25 HCC lesions treated by means of PEI one to 24 months before. At CT performed 3 to 5 weeks after injection, retention of Lipiodol was observed in 9 of 13 tumors that still contained viable neoplastic tissue and in 2 of 12 tumors proven to have undergone complete necrosis after PEI. The sensitivity and specificity of Lipiodol-CT were 69.2% and 83.3%, respectively. Thus, Lipiodol-CT seems to have limited diagnostic value after PEI, probably as a consequence of the alcohol-induced vascular damage, accounting for both false-negative and false-positive results. (orig.).

1994-07-01

246

Laparoscopic diagnosis and treatment of nonpalpable testis  

Scientific Electronic Library Online (English)

Abstract in english INTRODUCTION: Treatment of the cryptorchid testicle is justified due to the increased risk of infertility and malignancy as well as the risk of testicular trauma and psychological stigma on patients and their parents. Approximately 20% of cryptorchid testicles are nonpalpable. In these cases, the videolaparoscopic technique is a useful alternative method for diagnosis and treatment. MATERIALS AND METHODS: We present data concerning 90 patients submitted to diagnostic lapa (more) roscopy for impalpable testicles. Forty-six patients (51.1%) had intra-abdominal gonads. In 25 testicles of 19 patients, we performed a two stage laparoscopic Fowler-Stephens orchiopexy. The other 27 patients underwent primary laparoscopic orchiopexy, in a total of 29 testicles. RESULTS: We obtained an overall 88% success rate with the 2 stage Fowler-Stephens approach and only 33% rate success using one stage Fowler-Stephens surgery with primary vascular ligature. There ...

2008-06-01

247

Investigation of cardio-vascular reflex in atomic bomb survivors, (2)  

Energy Technology Data Exchange (ETDEWEB)

Electrographic R-R interval variation was examined in a total of 915 A-bomb survivors exposed at {<=}2,000 m from the hypocenter (the {<=} 2,000 m group) and a total of 1,162 A-bomb survivors exposed at >3,000 m or entered the city after the A-bombing (the >3,000 m group). Coefficient of variation (CV) for R-R interval variation on ECG tended to be decreased with advancing age in the >3,000 m group, irrespective of sex. Especially for men in this group, CV values were significantly lower for the age group of 45 to 54 years than the groups of 65 to 74 years and 75 to 84 years. Similar tendency was observed for CV values at deep breath. Decreased CV values tended to be associated with a decrease in glucose tolerance in both men and women of the >3,000 m group. In comparing the aforementioned CV values with those in the {<=}2,000 m group, there was no significant difference between the groups. R-R interval variation on ECG was found independent of exposure condition, ...

1990-11-01

248

Influence of manufacturing methods on the homogeneity and properties of nitinol tubular stents  

Energy Technology Data Exchange (ETDEWEB)

Nitinol has found growing applications in vascular stents, with the recent introduction on the market of a number of new nitinol tubular devices for coronary and peripheral usage. These stents can be produced either through the expansion of a pattern cut on a small tube (pre-cut) or by cutting the deployed design on a tube of a larger size (pre-expanded). The aim of the study was to analyze the differences of properties induced by the two manufacturing methods. For this purpose, differential scanning calorimetry (DSC) measurements were performed on various specimens from the two types of stents. A first set of measurements shows that pre-expanded stents exhibit usual A<->R<->M transformations whereas multi-stage transformations occur for pre-cut stents. Two types of DSC specimens were then prepared for each stent, corresponding to the straight sections and the curved parts of the stent. It is shown that the pre-cut stents exhibit less ...

2001-11-01

249

Infected nonunion of the long bones.  

Science.gov (United States)

BACKGROUND: Although definitions vary, infected nonunion has been defined as a state of failure of union and persistence of infection at the fracture site for 6 to 8 months.>). Infected nonunions of the supracondylar region of the femur are uncommon and are mostly due to a severe open fracture with extensive comminution and segmental bone loss or after internal fixation of a comminuted closed fracture. Associated factors include exposed bone devoid of vascularized periosteal coverage for more than 6 weeks, purulent discharge, a positive bacteriological culture from the depth of the wound, and histologic evidence of necrotic bone containing empty lacunae. Soft-tissue loss with multiple sinuses, osteomyelitis, osteopenia, complex deformities with limb-length inequality, stiffness of the adjacent joint, polybacterial multidrug-resistant infection, and smoking all complicate treatment and recovery. Although uncommon in incidence, infected nonunions of the long bones ...

2007-08-01

250

In vitro corrosion, cytotoxicity and hemocompatibility of bulk nanocrystalline pure iron  

International Nuclear Information System (INIS)

Bulk nanocrystalline pure iron rods were fabricated by the equal channel angular pressure (ECAP) technique up to eight passes. The microstructure and grain size distribution, natural immersion and electrochemical corrosion in simulated body fluid, cellular responses and hemocompatibility were investigated in this study. The results indicate that nanocrystalline pure iron after severe plastic deformation (SPD) would sustain durable span duration and exhibit much stronger corrosion resistance than that of the microcrystalline pure iron. The interaction of different cell lines reveals that the nanocrystalline pure iron stimulates better proliferation of fibroblast cells and preferable promotion of endothelialization, while inhibits effectively the viability of vascular smooth muscle cells (VSMCs). The burst of red cells and adhesion of the platelets were also substantially suppressed on contact with the nanocrystalline pure iron in blood circulation. A clear ...

2010-12-01

251

Hepatobiliary scintigraphy in current pediatric practice  

Energy Technology Data Exchange (ETDEWEB)

Hepatobiliary scintigraphy is the only non-invasive technique providing real-time assessment of hepatocytes function and bile progression from the liver to the intestine; for this reason it is of great importance in the study of jaundice and many other disorders of the liver and the biliary tract in children. Ultrasonography is the initial method of evaluating the intra- and extrahepatic bile ducts dilatation: the differential diagnosis between biliary atresia and neonatal hepatitis cannot however be done without hepatobiliary scintigraphy. Cystic fibrosis patients also require hepatobiliary scintigraphy; liver and biliary tract disease can really occur independently of the underlying disease severity and the presence of steatorrhoea. Hepatobiliary imaging in children who have undergone liver transplantation is of major importance; it can assess vascularity, parenchymal function biliary drainage, possible presence of a bile leak and obstruction; it has very good ...

1998-06-01

252

Free-electron laser beam  

International Nuclear Information System (INIS)

The principle and history of free-electron laser (FEL), first evidenced in 1977, the relationship between FEL wavelength and output power, the high-power FEL driven by the superconducting linac, the X-ray FEL by the linac, and the medical use are described. FEL is the vacuum oscillator tube and essentially composed from the high-energy linac, undulator and light-resonator. It utilizes free electrons in the vacuum to generate the beam with wavelength ranging from microwave to gamma ray. The first high-power FEL developed in Japanese Atomic Energy Research Institute (JAERI) is based on the development of superconducting linac for oscillating the highest power beam. In the medical field, applications to excise brain tumors (in US) and to reconstruct experimentally blood vessels in the pig heart (in Gunma University) by lasing and laser coagulator are in progress with examinations to remove intra-vascular cholesterol mass by irradiation of 5.7#mu#m FEL beam. Cancer ...

2003-06-01

253

Effects of chronic treatment with honokiol in spontaneously hypertensive rats.  

Science.gov (United States)

The present study was performed to evaluate the antihypertensive effects of honokiol in vivo in spontaneously hypertensive rats (SHR). The effects of honokiol were investigated by determination of the blood pressure, vascular reactivity, oxidative parameters, and histologic change in the aorta. Long-term administration of honokiol (400 mg/kg/d) to SHR decreased systolic blood pressure significantly. Honokiol (200, 400 mg/kg/d) enhanced the aortic relaxation in response to acetylcholine after 49-d treatment, but had no significant effects on the relaxation to sodium nitroprusside. The oral administration of honokiol significantly increased the plasma level of NO(2(-))/NO(3(-)), but decreased the level of malondialdehyde in liver of SHR compared with the control vehicle. In addition, SHR administered honokiol showed significant reductions in the elastin bands and media thickness in the aorta. These results suggest that chronic treatment with honokiol exerts an ...

2010-01-01

254

Critical loads for vegetation. Definition, use and limits. Charges critiques pour la vegetation  

Energy Technology Data Exchange (ETDEWEB)

Vegetation is a key compartment of ecosystems. It contains a large part of the biodiversity at the species level. For the evaluation of critical loads, we have to separate different receptors: lower plants (algae, fungi, lichens and mosses) and vascular plants. Trees must be distinguished due to their economic value. We analyze the different changes that pollution produces on vegetation: the state of health of individuals, changes in the biology and genetics at the population level, changes in the biodiversity or the specific composition at the community level. Calculation of critical loads is based on observational or experimental studies, in more or less controlled environments. However, they cannot yet be obtained through models of vegetation changes. Some results have been acquired at the European level, mainly for critical loads for nitrogen, but these results have come mostly from Northern Europe. Moreover, only heathlands and acidic forests have been studied ...

1993-06-01

255

Cognitive performance correlates with cerebrovascular impairments in multi-infarct dementia  

International Nuclear Information System (INIS)

Cerebral blood flow (CBF) was measured by the "1"3"3Xe inhalation method in patients with multi-infarct dementia (MID, N = 26), Alzheimer's dementia (AD, N = 19), and among age-matched, neurologically normal, healthy volunteers (N = 26). Cognitive performance was assessed in all subjects using the Cognitive Capacity Screening Examination (CCSE). Cerebral vasomotor responses were calculated from differences in values of mean hemispheric gray matter blood flow (Delta CBF) measured during inhalation of 100% oxygen (hyperoxia) compared with CBF measured while breathing room air. Significant correlations were found between CCSE performance and vasomotor responsiveness in patients with MID (P less than .01), but not in patients with AD or in neurologically normal volunteers. Loss of vasomotor responsiveness is an indicator of cerebrovascular disease with rigidity and/or loss of reactivity of cerebral vessels, which impairs cerebrovascular responses to situational demands and predisposes to ...

256

Closed loop obstructions of the small bowel: role of Computed Tomography  

International Nuclear Information System (INIS)

Small bowel obstructions can be distinguished into more simple and closed loop obstructions. The latter is a more severe condition which is often complicated by strangulation with vascular impairment, edema and intramural and mesenteric hemorrhage. Consequent arterial insufficiency rapidly leads to ischemia, infarction and necrosis. The radiologist plays a role in the early recognition of the closed loop obstruction and of any sign of strangulation. The role of CT in the diagnosis and workup of patients with suspected intestinal occlusion has been analyzed in the literature with reported 63% sensitivity, 78% specificity and 66% accuracy. CT is also capable of revealing the causes of occlusion in 73-95% of cases. The above CT signs allow to identify closed loop obstruction and also small bowel strangulation, thus supplying a valuable contribution to diagnosis and accurate preoperative evaluation. The conclusion is that CT can accurately demonstrate the presence of ...

1999-01-01

257

Aliskiren reduces vascular pathology in diabetic retinopathy and oxygen-induced retinopathy in the transgenic (mRen-2)27 rat  

British Library Electronic Table of Contents (United Kingdom)

Aim/hypothesis We examined whether the renin inhibitor, aliskiren, provides similar or greater protection than ACE inhibition from non-proliferative diabetic retinopathy and from the proliferative neoangiogenesis of oxygen-induced retinopathy. Methods Transgenic (mRen-2)27 rats, which overexpress mouse renin and angiotensin in extra-renal tissues, were studied. For diabetic studies, non-diabetic, diabetic (streptozotocin, 55?mg/kg), diabetic + aliskiren (10?mg?kg?1?day?1, pump), or diabetic + lisinopril (10?mg?kg?1?day?1, drinking water) rats were evaluated over 16?weeks. For oxygen-induced retinopathy studies, rats were exposed to 80% oxygen (22?h/day) from postnatal days?0 to 11, and then room air from postnatal days?12 to 18. Aliskiren (10 or 30?mg?kg?1?day?1, pump) or lisinopril (10?mg...

2011-01-01

258

Aggressive Ewing's sarcoma appearing as a cold lesion on bone scan  

International Nuclear Information System (INIS)

Ewing's sarcoma classically presents as a hot spot on bone scan as a result of increased vascularity of the tumor and new bone formation. Purpose We report and analyze an uncommon pattern of a 'cold' lesion in Ewing's sarcoma on bone scan and its pathophysiologic significance. Case report A 15-year-old boy complaining of thigh pain. CT scan evoked Ewing's sarcoma or osteitis. MRI evoked chronic osteitis. Scintigraphy showed a fairly intense and heterogeneous uptake on the femoral lesion and no abnormal uptake elsewhere. Biopsy showed none pathologic pattern. Three months later, a second biopsy concluded to Ewing's sarcoma. Bone scan showed a larger lesion with peripheral intense uptake centered by enlarged 'cold' area in the left femoral diaphysis and no evident bone metastasis. The patient underwent chemotherapy and surgery. Three months later, bone scan showed extensive skeletal metastasis. Conclusion Ewing's sarcoma appears usually as an intense lesion on bone ...

2009-10-01

259

A kinetic and microautoradiographic study of sup 14 C-sucrose translocation into developing wheat grains  

Energy Technology Data Exchange (ETDEWEB)

The kinetics of {sup 14}C-photosynthate import by developing wheat grains was followed after pulse-labeling the flag leaf with {sup 14}CO{sub 2}. Samples were collected from four successive points along the transport pathway to and within the grain: exuding aphid stylets on the peduncle, exuding grain pedicels, the grain crease tissues, and the liquid contents of the endosperm cavity. In addition, microautoradiographs were prepared of the grain crease tissues during movement of the {sup 14}C pulse into the grain. At all times, sucrose accounted for 93 to 97% of the total {sup 14}C present at all four sampling sites. The main features of the {sup 14}C kinetics could be accounted for by a simple compartmental model consisting of sucrose pools in series. Microautoradiographs of the crease tissues showed fairly uniform labeling of vascular parenchyma at all times, with a sharp gradient in labeling across the chalaza to the nucellus. Thus the principal resistance to ...

1991-05-01

260

A habitat template approach to green building surfaces  

Energy Technology Data Exchange (ETDEWEB)

The use of entire plant communities of native species is gaining interest in the green roof industry. Plant communities must be matched with environmental conditions that mimic conditions in their original habitats. Urban built environments do not differ significantly from the rocky outcrops with poor, shallow soil that many plants colonize. This paper provided details of an experiment investigating the impact of plant community structure and species diversity on living roof performance. The aim of the experiment was to determine the impact of species diversity on precipitation interception, nutrient retention, temporal biomass constancy and roof temperature constancy. The diversity treatment included separate monocultures of 8 species in the community, randomly determined mixtures of 4 species, and a mixture of all 8. Functional groups included mosses, liverworts, colonial algae and a mycorrhizal inoculum. In a second experiment, between 1 and 4 of the functional groups were added to ...

2005-07-01

261

A Polyhydroxybutyrate Biodegradable Stent: Preliminary Experience in the Rabbit  

International Nuclear Information System (INIS)

Purpose: The lifelong persistence of foreign bodies within the arteries may contribute to restenosis. Thus,biodegradable devices might decrease recurrence rates. Methods: Eleven polyhydroxybutyrate biodegradable stents and 13 tantalum stents were implanted into the iliac arteries of New Zealand white rabbits for up to 30 weeks. After killing the animals,the specimens were harvested, fixed in formalin, processed in paraffin,and stained. Results: Polyhydroxybutyrate instigated intense inflammatory and proliferative reactions with an increase in collagen (2.4- to 8-fold vs native segments), thrombosis and in-stentlumen narrowing (375.5-606.6 mm vs 655.6 #+-# 268.8 mm in native segments). The elastic membranes were destroyed in all specimens. The tantalum stents increased the in-stent lumen progressively (769.7 #+-# 366.6 mm vs 1309.9 #+-# 695.3 mm),penetrated the external elastic membrane, and increased mural collagen content (6- to 8.6-fold vs native segments). Neither restenoses nor ...

2002-03-01

262

Use of sting-response techniques for simulate diagnostics in human esophagus; Uso de tecnicas estimulo-respuesta para simular diagnosticos en esofago humano  

Energy Technology Data Exchange (ETDEWEB)

In this work a study of simulation of the gamma graphic studies that are carried out in human esophagus in the Dept. of Nuclear Medicine of the 'Celestino Hernandez Robau Hospital of Santa Clara is presented. For the investigation tubular reactors were used and sting-response techniques with radioactive tracer of Technetium 99 metastable to a concentration of 1 mCi and several flows were applied. The distribution curves of residences times were obtained, those that respond to an equation of the type: Y = A + B exp (- exp((x-C)/D)) - ((x-C/D)+1). They were also carried out, optimizations studies of the doses of the radioactive to give to the patients from 1 mCi (that is the one used in studies) up to 0,5 mCi, and the influences on the obtained distributions of residence time were analyzed. It was confirmed the possibility to lower the doses with clear information of the signal. It was also carried out a simulation of the attenuation of the radiations that takes place in the ...

2003-07-01

263

Use of coal as fuel for chemical-looping combustion with Ni-based oxygen carrier  

Energy Technology Data Exchange (ETDEWEB)

Chemical-looping combustion is an indirect combustion technology with inherent separation of the greenhouse gas CO{sub 2}. The feasibility of using NiO as an oxygen carrier during chemical-looping combustion of coal has been investigated experimentally at 800-960{degree}C in the present work. The experiments were carried out in a fluidized bed, where the steam acted as the gasification-fluidization medium. Coal gasification and the reaction of oxygen carrier with the water gas take place simultaneously in the reactor. The oxygen carrier particles exhibit high reactivity above 900{degree}C, and the dry basis concentration of CO{sub 2} in the exit gas of the reactor is nearly 95%. The flue gas composition as a function of the reactor temperature and cyclic reduction number is discussed. At 800-960{degree}C, the dry basis concentration of CO{sub 2} in the flue gas presents a monotonously increasing trend, whereas the dry basis concentration of CO, H{sub 2}, and CH{sub 4} decreases ...

2008-12-15

264

The two means method for the attenuation coefficient determination of archaeological ceramics from the North of Parana; Metodo dos dois meios para a determinacao do coeficiente de atenuacao de ceramicas arqueologicas do norte do Parana  

Energy Technology Data Exchange (ETDEWEB)

This work reports an alternative methodology for the linear attenuation coefficient determination ({mu} {rho}) of irregular form samples, in such a way that is not necessary to consider the sample thickness. With this methodology, indigenous archaeological ceramics fragments from the region of Londrina, north of Parana, were studied. These ceramics fragments belong to the Kaingaing and Tupiguarani traditions. The equation for the {mu} {rho} determination employing the two mean method was obtained and it was used for {mu} {rho} determination by the gamma ray beam attenuation if immersed ceramics, by turns, in two different means with known linear attenuation coefficient. By the other side, {mu} theoretical value was determined with the XCOM computer code. This code uses as input the ceramics chemistry composition and provides an energy versus mass attenuation coefficient table. In order to validate the two mean method validation, five ceramics samples of thickness 1.15 cm and 1.87 cm ...

1997-12-31

265

Subsidence monitoring in the Cerro Prieto geothermal field, B.C., Mexico; Monitoreo de la subsidencia en el campo geotermico de Cerro Prieto, B.C., Mexico  

Energy Technology Data Exchange (ETDEWEB)

Since 1977, precise leveling surveys have been carried out to determine whether there have been vertical terrain displacements and the subsidence speed rate in the Cerro Prieto Geothermal field area. The elevation contours for each leveling show since 1962 that there was a basin that involves the geothermal field. The differences in the last three levelings show a generalized subsidence between Cerro Prieto (BN 10049) and Imperial faults (BN CD-14). [Spanish] A partir de 1977 se realizan trabajos de nivelacion de precision, con el fin de conocer si existen desplazamientos verticales del terreno y cual es la velocidad de subsidencia que existe en el area del Campo Geotermico de Cerro Prieto. Las configuraciones de cotas para cada uno de los anos nivelados, muestran que desde 1962 existe una cuenca que incluye al campo geotermico; la diferencia de cotas obtenidas en las tres ultimas nivelaciones, indican una subsidencia generalizada entre la Falla Cerro Prieto (BN ...

1999-04-01

266

Self-construction of a solar water heater; Calentador solar de agua de auto-construccion  

Energy Technology Data Exchange (ETDEWEB)

In this work a flat receiver of self construction is shown with relatively low cost and easy manufacture, but with a thermal efficiency superior to 40% for applications at temperatures less than 60 degrees Celsius, that allows satisfying international standards in this respect. The heater has been matter of study in open courses distributed in the Universidad Autonoma de la Ciudad de Mexico (UACM) oriented to that the participants construct their own system, in addition to its installation and tests. The obtained results have been excellent. The massive use of efficient solar receivers of self-construction can truly help to the decreasing of the gas discharges of greenhouse effect. [Spanish] En este trabajo se presenta un captador plano de auto construccion con relativamente bajo costo y facil manufactura, pero con un rendimiento termico superior a 40% para aplicaciones a temperatura menos de 60 grados centigrados que le permite satisfacer estandares ...

2009-07-01

267

Occupational exposure to benzene: a prevention program for employees and contractors; PPEOB - Programa de Prevencao a Exposicao Ocupacional ao Benzeno para Empregados Proprios e Contratados  

Energy Technology Data Exchange (ETDEWEB)

PETROBRAS/TRANSPETRO Pipelines and Terminals has 500 regular employees and 5.064 out sourced workers in its Southeast Division. The out sourced employees work through 125 contracts involving a wide range of activities such as maintenance, operational, pipeline launching , engineering, administrative and auxiliary services. Among these workers, 200 people are subjected to benzene occupational exposure, which might be present in the products we transport in our pipelines. Benzene is recognized as a carcinogen according to ACGIH and Brazilian Ministry of Labour regulation NR- 15. Exposure to benzene in an uncontrolled way, be it chronic or sharp, may affect the worker's health such as: hematological alterations, neoplasys, neurobehavior alterations. Our program PPEOB (acronym in Portuguese for benzene occupational exposure prevention program) involved the work force and fosters health by anticipation, recognition, evaluation and control of the situations that may result in ...

2004-07-01

268

Methodology for sizing, energy analysis and selection of equipment for a biomass gasifier to drive an internal combustion engine; Metodologia de dimensionamento, analise energetica e selecao de equipamentos de um gaseificador de biomassa para o acionamento de um motor de combustao interna  

Energy Technology Data Exchange (ETDEWEB)

Alter both oil crisis, of 1973 and 1979, a bad effect of the elevated costs and continuously increment of the oil prices was noted, for this reason, the interest for renewable energies sources widely available in developing countries was increased. All over the world, governments have formulated main objectives for energies savings and search for friendly technologies, taking into account the effects related with the environment. The imminent scarcity of fossil fuels has made humanity the rational use of primary energies, as a result of these; new plants with improved technology have been conceived taking into account energy savings and efficiency improvement. In this context, biomass gasification technologies are important, since they consist in techniques of parallel production of electricity and heat from just one fuel. This work consists in the development of a gasifier down draft of 100 kW for an internal combustion engine, which includes its sizing process and its energy ...

2006-07-01

269

Energy generation for sustainable development with innovation technology and utilization of biomass residue; Geracao de energia para o desenvolvimento rural sustentavel com inovacao tecnologica de aproveitamento de biomassa residual  

Energy Technology Data Exchange (ETDEWEB)

In the present work, the introduction of alternative energy of biogas in agricultural communities for the sustainable development was studied through exploitation of residual biomass and also getting as by-product the biological fertilizer. A fast composting of the domestic residue with the organic was made possible where part of this residue after processing was taken together with effluent to the biodigestor. The bibliographical research on the processes of generation of biogas, about composting and the equipment for processing had been carried through. The projects Engineering with the use of computational tools had been developed with the Software Super Pro 4,9 Design and ORC GPEC 2004 by our research group. Five case studies had been elaborated, where different scenes related with our innovation, that uses of the residue for the composting together with domestic effluent for digestion. Several economic parameters were obtained and our work proved the viability about the use of ...

2004-07-01

270

Development of bioenergy technology for rural micro mills production of milk, ice and bio fertilizer; Desenvolvimento de tecnologia de bioenergia rural para micro usinas de producao de leite, gelo e bio fertilizante  

Energy Technology Data Exchange (ETDEWEB)

The generation of thermal energy is the great importance for the agribusiness of dairy industry to conservation the quality of milk, taking into account that the electricity is the main source currently used for the thermal energy input. The small agribusiness dairy industry currently practiced in Brazil faces several problems related to the cost of electricity and the distance of rural properties of networks of power. In the current scenario of Brazilian dairy production, there is need for the generation of cold for the milk cooling, and also the heat for the production of hot water around 50 deg C to 60 deg C and also for cleaning of equipment used for milk production and processing. The main objective of this study is the modeling and simulation of integrated recovery process of solid waste, effluents and bioconversion. The specific project objectives are: comparison study of options and technological routes of low cost material for power generation using conventional and innovative ...

2008-07-01

271

Decay of H{sub 2}{sup -} anions in solid parahydrogen by quantum tunneling: observations of electron bubbles  

Energy Technology Data Exchange (ETDEWEB)

Decay mechanism of H{sub 2}{sup -} anions produced by {gamma}-ray or X-ray radiolysis of solid para-H{sub 2} (p-H{sub 2}) has been studied using high-resolution ESR spectroscopy in the temperature range between 2.7-6.6 K. The results can be summarized as follows; First, the decay rate constant of the H{sub 2}{sup -} anion is not proportional to initial yields of reactive species such as H radical and cation but proportional to concentrations of HD and D{sub 2} impurities in p-H{sub 2}. Second, ESR spectra assigned as electron bubbles were observed in solid p-H{sub 2} containing large amount of HD or D{sub 2} (11 mol %), while they were not observed in pure solid p-H{sub 2}. Third, the decay rate constant of the H{sub 2}{sup -} anion increases with the decrease in temperature between 2.7-5 K, while it decreases with the decrease between 5-6.6 K. Fourth, the decay of the H{sub 2}{sup -} anion is suppressed by addition of ortho-H{sub 2} (o-H{sub 2}) impurity. The ...

1998-02-01

272

Ophidian envenomation strategies and the role of purines.  

Science.gov (United States)

Snake envenomation employs three well integrated strategies: prey immobilization via hypotension, prey immobilization via paralysis, and prey digestion. Purines (adenosine, guanosine and inosine) evidently play a central role in the envenomation strategies of most advanced snakes. Purines constitute the perfect multifunctional toxins, participating simultaneously in all three envenomation strategies. Because they are endogenous regulatory compounds in all vertebrates, it is impossible for any prey organism to develop resistance to them. Purine generation from endogenous precursors in the prey explains the presence of many hitherto unexplained enzyme activities in snake venoms: 5'-nucleotidase, endonucleases (including ribonuclease), phosphodiesterase, ATPase, ADPase, phosphomonoesterase, and NADase. Phospholipases A(2), cytotoxins, myotoxins, and heparinase also participate in purine liberation, in addition to their better known functions. Adenosine contributes to prey immobilization ...

2002-04-01

273

Nodular fasciitis: correlation of MRI findings and histopathology  

Energy Technology Data Exchange (ETDEWEB)

Objective: To compare the histopathology of nodular fasciitis (NF) with the magnetic resonance imaging (MRI) findings in order to evaluate the basis of the MR signal characteristics. Design and patients: Ten patients with NF, nine females and 1 male, with an age ranging from 13 to 58 years (mean 26.8 years) were studied. MRI findings, available in all 10 patients, were compared with the histopathology in nine patients, and an area-to-area comparative study of the whole specimen section histopathology and MRI was performed in two patients. Results: On the basis of an excisional biopsy or resection specimen, the nine lesions were classified into myxoid (n=4), cellular (n=3) and fibrous (n=2) subtypes. Four myxoid lesions with a subcutaneous location showed a homogeneous SI comparable with muscle on T1-weighted images, high SI on T2-weighted images, and had homogeneous enhancement. One cellular lesion presented with homogeneous, slightly higher SI than muscle on T1-weighted images and ...

2002-03-01

274

Computed tomography of the mediastinal lesion  

Energy Technology Data Exchange (ETDEWEB)

Authors retrospectively analyzed the CT findings of mediastinal lesions in surgically or clinically confirmed 37 cases at Kosin Medical College during recent 4 years from September 1979 to August 1983. 1. Among 37 caes, malignant lymphoma were 7 cases, thymoma and vascular lesion or anomaly were 5 cases respectively, benign teratoma and tuberculous mediastinal lymphadenitis and neurogenic tumor were 4 cases respectively, pericardial cyst were 2 cases, bronchogenic cyst, non-specific cyst, pancreatic pseudocyst, mesothelioma, Bochdalek hernia was 1 case respectively. 2. The sex ratio between male and female was about 1 : 1 and the majority of the patients with malignant lymphoma and teratoma was under 20 years old. 3. CT findings of the each mediastinal lesion. 1) Primary mediastinal malignant lymphoma. (1) A large, matted, continuous and midline-crossing mass was observed in the superior and the anterior mediastinums in all cases. (2) In 3 cases, irregular lower ...

1984-09-15

275

Voltage and reactive power control by means of static compensators of vars in electric power systems; Control de voltaje y potencia reactiva mediante compensadores estaticos de Vars en sistemas electricos de potencia  

Energy Technology Data Exchange (ETDEWEB)

In this thesis a study is made of the of voltage characteristics and reactive power control in the transmission network of the Electric Power Systems (EPS) with static compensators of VARs (SCVs). The necessity of voltage and reactive power control and the application of SCVs as a solution means for three representative operation stages of the EPS, considering balanced operation conditions and fundamental frequency is analyzed: Operation in the presence of incremental voltage changes, quasi-stationary operation or steady state and behavior at the occurrence of big disturbances. The application of SCVs to systems of integral transmission is in general a closed loop control system, reason why the analysis of the interaction of the system EPS-SCV is considered as an essential part of the voltage and reactive power control study. Firstly, the response analysis of the control loop is made for incremental voltage changes, representing the power system by means of its equivalent of Thevenin ...

1987-07-01

276

Proposal of procedures to prevent errors in radiotherapy based in learned lessons of accidental expositions; Proposta de procedimentos para evitar erros em radioterapia baseados em licoes aprendidas de exposicoes acidentais  

Energy Technology Data Exchange (ETDEWEB)

In order to consider some procedures to prevent errors in radiotherapy based in learned lessons of accidental expositions and in accordance with information contained in international reports elaborated by International Atomic Energy Agency (IAEA) and of the data base availability by the European group Radiation Oncology Safety Information System (ROSIS) on the events, a research of the occurred errors was performed. For the evaluation of the incidents a data base based in the ROSIS and added plus a parameter was created 'type of error'. All the stored data make possible the evaluation of the 839 incidents in terms of frequency of the type of error, the process of detention, the number of reached patients and the degree of severity. Of the 50 types of found errors, the type of error more frequently was 'incorrect treatment coordinate', confirmed with the data of literature and representing 28,96 por cent of the total of the incidents. The results ...

2007-07-01

277

Mechanodynamical analysis of nickel-titanium alloys for orthodontics application; Analise mecanodinamica de ligas de niquel-titanio para aplicacao ortodontica  

Energy Technology Data Exchange (ETDEWEB)

Nickel-titanium alloys may coexist in more than one crystalline structure. There is a high temperature phase, austenite, and a low temperature phase, martensite. The metallurgical basis for the superelasticity and the shape memory effect relies in the ability of these alloys to transform easily from one phase to another. There are three essential factors for the orthodontist to understand nickel-titanium alloys behaviour: stress; deflection; and temperature. These three factors are related to each other by the stress-deflection, stress-temperature and deflection-temperature diagrams. This work was undertaken with the objective to analyse commercial nickel-titanium alloys for orthodontics application, using the dynamical mechanical analyser - DMA. Four NiTi 0,017 X 0,025'' archwires were studied. The archwires were Copper NiTi 35 deg C (Ormco), Neo Sentalloy F200 (GAC), Nitinol Superelastic (Unitek) and NiTi (GAC). The different mechanodynamical properties such as ...

2002-07-01

278

Very low-dose hyper-radiosensitivity: impact for radiotherapy of micrometastases; Hyperradiosensibilite aux tres faibles doses: impact en radiotherapie des micrometastases  

Energy Technology Data Exchange (ETDEWEB)

Radio-biologists have pointed out a novel radiobiological phenomenon observed in many tumor and normal cell lines: hyper-radiosensitivity to very low-dose (H.R.S.) followed by induced radioresistance (I.R.R.) after a threshold dose of 0.1-0.3 Gy that depends on the cell line. Radioresistance at high dose (i.e. higher than 0.5 Gy) and metastatic potential of tumor cells are likely major factors of failure in radiotherapy. A careful review of literature suggests that: 1) radiotherapy does not increase the metastatic potential of tumor cells; 2) radioresistance at high dose and metastatic potential are not related. However, inside a given tumor cell line, highly metastatic clones may elicit more cells showing H.R.S; or are more radiosensitive at high dose than poorly metastatic ones. Recent data obtained from molecular techniques (comet and immunofluorescence assays) applied to single cells irradiated at very low radiation doses (1-100 mGy) suggest that DNA single-strand breaks (S.S.B.) ...

2007-09-15

279

Transcription regulation of the vegf gene by the BMP/Smad pathway in the angioblast of zebrafish embryos  

Science.gov (United States)

Vascular endothelial growth factor (VEGF) is a mitogen that is critically involved in vasculogenesis, angiogenesis, and hematopoiesis. However, what and how transcription factors participate in the regulation of vegf gene expression are not fully understood. Here we report the cloning and sequencing of the zebrafish vegf promoter which revealed that the promoter contains a number of bone morphogenetic protein (BMP)-activated Smad binding elements (SBE), implicating Smad1 and Smad5 in the regulation of BMP-induced expression of vegf. Electrophoretic mobility shift assays of adding recombinant Smad proteins to the SBE-containing DNA oligonucleotides that represent portions of zebrafish vegf promoter resulted in mobility shift of the oligonucleotides. These changes demonstrate potential interactions between Smad1/5 and the vegf promoter. Reporter activity assays using the wild-type or SBE-deleted vegf promoters to drive the luciferase reporter gene expression revealed ...

2005-04-01

280

The mechanism of metal nanoparticle formation in plants: limits on accumulation  

Energy Technology Data Exchange (ETDEWEB)

Metal nanoparticles have many potential technological applications. Biological routes to the synthesis of these particles have been proposed including production by vascular plants, known as phytoextraction. While many studies have looked at metal uptake by plants, particularly with regard to phytoremediation and hyperaccumulation, few have distinguished between metal deposition and metal salt accumulation. This work describes the uptake of AgNO{sub 3}, Na{sub 3}Ag(S{sub 2}O{sub 3}){sub 2}, and Ag(NH{sub 3}){sub 2}NO{sub 3} solutions by hydroponically grown Brassica juncea and the quantitative measurement of the conversion of these salts to silver metal nanoparticles. Using X-ray absorption near edge spectroscopy (XANES) to determine the metal speciation within the plants, combined with atomic absorption spectroscopy (AAS) for total Ag, the quantity of reduction of Ag{sup I} to Ag{sup 0} is reported. Transmission electron microscopy (TEM) showed Ag particles of ...

2009-08-15

281

The influence of different SPECT reconstruction algorithms on cardiac ischemia with the use artificial neural networks  

International Nuclear Information System (INIS)

The aim of the study was the attempt to evaluate the influence of two different methods of cardiac perfusion SPECT reconstruction (FBP and ITW) on clinical efficacy in diagnosing the coronary artery disease as well as the cardiac ischemia detection in three areas of heart vascularized by main coronary arteries: LAD, LCX and RCA with the use of artificial neural networks (ANN). The study was performed retrospectively with the use of the diagnostic image records as well as clinical dataset of 43 patients. Myocardial perfusion stress/rest SPECT study and X-ray coronarography data were evaluated for each patient. The results of coronary angiography were considered the reference method. The cardiac SPECT data were reconstructed using the two different methods: filtered backprojection (FBP) and iterative Wallis method (ITW). The local perfusion deficits denominated in stress and rest study in three main vessel cardiac segments were the main input values for the ANN. The ...

282

The effect of elevated carbon dioxide on a Sierra-Nevadan dominant species: Pinus ponderosa  

Energy Technology Data Exchange (ETDEWEB)

The impact of increasing atmospheric C0{sub 2} has not been fully evaluated on western coniferous forest species. Two year old seedlings of Pinusponderosa were grown in environmentally controlled chambers under increased C0{sub 2} conditions for 6 months. These trees exhibit morphological, physiological, and biochemical alterations when compared to our controls. Analysis of whole plant biomass distribution has shown no significant effect to the root to shoot ratios, however needles subjected to elevated C0{sub 2} exhibited an increased overall specific needle mass and a decreased total needle area. Morphological changes at the needle level included decreased mesophyll to vascular tissue 91 ratio and variations in starch storage in chloroplasts. The elevated CO{sub 2} increased internal CO{sub 2} concentrations and assimilation of carbon. Biochemical assays revealed that ribulose-bisphosphate carboxylase specific activities increased on per unit area basis with ...

1995-01-01

283

Regional spinal cord blood flow during local cooling  

Energy Technology Data Exchange (ETDEWEB)

We used the tissue distribution of ({sup 14}C)butanol to quantitate regional blood flow in the spinal cord (RSCBF) of pentobarbital-anesthetized, normothermic rats in which segmental local cooling pentobarbital-anesthetized, normothermic rats in which segmental local cooling of the spinal cord (to 25-28{degrees}C) at vertebral levels C4-C6 (n = 6) or T13-L1 (n = 6) was induced. Thirty minutes later, blood flow measurements were made at seven levels of the spinal cord and in the sciatic nerve trunks and biceps femoris muscles. Sham-cooled rats served as controls (n = 12). In control rats, RSCBF varied between 41.5 +/- 2.4 and 65.1 +/- 3.2 ml.min-1.100 g-1. Local cooling of the C4-C6 cord segment reduced RSCBF by 32%, from 65.1 +/- 3.2 to 44.4 +/- 3.5 ml.min-1.100 g-1 (P less than 0.01). Tissue vascular resistance (R) in the cooled C4-C6 segment was elevated versus control. There were no other changes in RSCBF at the other cord levels or in the cauda equina. ...

1990-06-01

284

Quantitative bone scintigraphy. A study in patients with prostatic carcinoma  

International Nuclear Information System (INIS)

Quantitative bone scintigraphy was performed in patients with prostatic carcinoma before orchiectomy as well as two weeks, two and six months after operation. The count rate was recorded as serial gamma camera images over the lower thoracic and all lumbar vertebrae from 1 to 240 min and at 24 h after injection of "9"9"Tc"m-MDP. In almost all abnormal vertebrae an increased count rate was observed within one hour after injection. Most of the vertebrae which were considered normal at 4 h after injection, but had an increased 24h/4h ratio developed into abnormal vertebrae later in the study. The patients with normal bone scintigrams showed no change in "9"9Tc"m-MDP uptake during the study. The reproducibility of quantitative bone scintigraphy was found to be #+-# 7% (1 SD). In response to therapy, most of the patients with abnormal bone scintigrams showed an increase in count rate two weeks after operation followed by a decrease to the pre-operative level after two months and a further ...

1985-06-02

285

Percutaneous intervention in the menagement of insufficient native arteriovenous hemodialysis fistulae  

Energy Technology Data Exchange (ETDEWEB)

To determine the effectiveness and patency of percutaneous intervention in insufficient native arteriovenous hemodialysis fistulae (AVFs). Between March 1997 and September 2001, 67 cases of insufficient native AVFs resulted from central vein lesion, PTA was performed in 48 cases, and thrombolytic therapy with or without PTA in 11. In eight of the cases, in which central vein stenosis had led to the insufficency, percutaneous transluminal angioplasty (PTA) was performed, and in three of the eight, a stent was inserted. Angiography findings and complications, as well as success and patency rates in the non-thrombosis and thrombosis group, were evaluated; the central vein lesion group was analysed separately. Among 84 lesions observed at angiography, three were 54 cases of stenosis, 17 of occlusion, and 13 of combined thrombosis. The lesions were located in a proximal vein (n=51), distal vein (n=14), artery (n=6), and at the site of anastomosis (n=13). In the central vein lesion group ...

2002-11-01

286

Molecular targeted treatment and radiation therapy for rectal cancer  

Energy Technology Data Exchange (ETDEWEB)

Background: EGFR (epidermal growth factor receptor) and VEGF (vascular endothelial growth factor) inhibitors confer clinical benefit in metastatic colorectal cancer when combined with chemotherapy. An emerging strategy to improve outcomes in rectal cancer is to integrate biologically active, targeted agents as triple therapy into chemoradiation protocols. Material and methods: cetuximab and bevacizumab have now been incorporated into phase I-II studies of preoperative chemoradiation therapy (CRT) for rectal cancer. The rationale of these combinations, early efficacy and toxicity data, and possible molecular predictors for tumor response are reviewed. Computerized bibliographic searches of Pubmed were supplemented with hand searches of reference lists and abstracts of ASCO and ASTRO meetings. Results: the combination of cetuximab and CRT can be safely applied without dose compromises of the respective treatment components. Disappointingly low rates of pathologic ...

2009-06-15

287

Magnetic resonance imaging of stents. Quantitative in vitro examination at 3 Tesla; Magnetresonanztomographie von Stents. Quantitative MR-Untersuchungen in vitro bei 3 Tesla  

Energy Technology Data Exchange (ETDEWEB)

The aim of this study was to qualitatively and quantitatively study MR artifacts of various stents on the basis of in vitro experiments. We were particularly interested whether sequence type and orientation of the stent with respect to the static magnetic field influences the artifact. We examined 18 stents of different material (nitinol, stainless steel, cobalt alloy), different design of the stent meshes (AccuLink, OmniLink, DynaLink, Xact, Protoge, Wallstent Monorail), different diameter (5-10 mm) and different length (18-58 mm) with a turbo spin echo (TSE), a 2D-fast low angle shot (FLASH) and a 3D-FLASH sequence. The MR images were examined qualitatively with respect to possible artifacts. Furthermore we examined the MR data quantitatively: The contrast-noise-ratio (CNR) was determined both within the stent and outside (within the tube); based on these values we calculated the transparency factor P, furthermore we calculated the apparent vascular lumen within ...

2009-07-01

288

Large intracranial vessel occlusive vasculopathy after radiation therapy in children: clinical features and usefulness of magnetic resonance imaging  

International Nuclear Information System (INIS)

Purpose: To assess the relationship between large intracranial vessel occlusive vasculopathy (vasculopathy) and radiation therapy, and to clarify the clinical efficacy of magnetic resonance (MR) imaging in the diagnosis and screening of the vasculopathy. Methods and Materials: We retrospectively evaluated the medical records and serial MR images for 32 pediatric patients, in whom radiation therapy had been given to fields including the circle of Willis and major cerebral arteries. All children had periodically undergone follow-up neurologic assessment and MR imaging examinations at Kanagawa Children's Medical Center for more than one year after radiation therapy (range 1.3-14 years). Patients who had not remained free of tumor progression up to the time of final evaluation were excluded. Results: Vasculopathy developed in 6 of 32 patients 2-13 years after radiation therapy. Three of them presented with transient ischemic attacks (TIA) and the other three showed infarctions without ...

1997-05-01

289

Kinetic analysis of transport and opioid receptor binding of ( sup 3 H)(-)-cyclofoxy in rat brain in vivo: Implications for human studies  

Energy Technology Data Exchange (ETDEWEB)

(3H)Cyclofoxy (CF: 17-cyclopropylmethyl-3,14-dihydroxy-4,5-alpha-epoxy-6-beta-fluoromorp hinan) is an opioid antagonist with affinity to both mu and kappa subtypes that was synthesized for quantitative evaluation of opioid receptor binding in vivo. Two sets of experiments in rats were analyzed. The first involved determining the metabolite-corrected blood concentration and tissue distribution of CF in brain 1 to 60 min after i.v. bolus injection. The second involved measuring brain washout for 15 to 120 s following intracarotid artery injection of CF. A physiologically based model and a classical compartmental pharmacokinetic model were compared. The models included different assumptions for transport across the blood-brain barrier (BBB); estimates of nonspecific tissue binding and specific binding to a single opiate receptor site were found to be essentially the same with both models. The nonspecific binding equilibrium constant varied modestly in different brain structures (Keq = ...

1991-03-01

290

Hilar cholangiocarcinoma: MR correlation with surgical and histological findings  

International Nuclear Information System (INIS)

Aim: To evaluate magnetic resonance cholangiography (MRC) with high-resolution dynamic gadolinium-enhanced magnetic resonance imaging (MRI) in determining the imaging features of hilar cholangiocarcinoma that relate to tumour extent and influence resectability. Materials and methods: Twenty-six patients that underwent resection were reviewed. Tumour location and extent, lobar atrophy, the degree of portal vein and hepatic artery involvement were recorded. The findings were correlated with surgical and histopathological findings. Results: Biliary assessment was concordant in 14 and discordant in eight of 14 stented and four of 12 non-stented patients. In 63/82 veins and 43/74 arteries results were fully concordant. The mean sensitivity, specificity, positive and negative predictive values (PPV, NPV) in predicting involvement of the main portal vein (MPV) at surgery were 83.3, 100, 100, and 92.5%; of the left main branch of the portal vein (LPV) were 100, 91.6, 93.3, and 100%; and of the ...

2010-10-01

291

Extracellular Protein Disulfide Isomerase Regulates Feedback Activation of Platelet Thrombin Generation Via Modulation of Coagulation Factor Binding.  

Science.gov (United States)

Background: Protein disulfide isomerase (PDI) controls platelet integrin function, tissue-factor (TF) activation, and concentrates at fibrin and thrombus formation sites of vascular injury. Objective: We investigated involvement of surface thiol isomerases and especially PDI, in thrombin-mediated thrombin amplification on human platelets. Methods/Results: Using a new developed thrombin-dependent platelet thrombin generation assay we observed that the feedback activation of thrombin generation on the platelet surface does not depend on TF, as anti-TF antibodies inhibiting TF-induced thrombin formation in platelet-depleted plasma had no effect compared to vehicle-treated controls. Feedback activation of thrombin generation in the presence of platelets was significantly diminished by membrane impermeant thiol blockers or by the thiol isomerase-inhibitors bacitracin and anti-PDI antibody RL90, respectively. Platelet thrombin formation depends on binding of coagulation ...

2011-09-19

292

Evaluation of the compressive mechanical properties of endoluminal metal stents.  

Science.gov (United States)

The mechanical properties of metal stents are important parameters in the consideration of stent design, matched to resist arterial recoil and vascular spasm. The purpose of this study was to develop a system for a standardized quantitative evaluation of the mechanical characteristics of various coronary stents. Several types of stents were compressed by external hydrostatic pressure. The stent diameter was assessed by placing a pair of small ultrasonic sono-crystals on the stent. From pressure-strain diagrams the ultimate strength and radial stiffness for each stent were determined. For all stents, except the MICRO-II and the Wiktor stent, the diameter decreased homogeneously until an ultimate compressive strength was exceeded, causing an abrupt collapse. Expanded to 3 mm, the mechanical behavior of the beStent, the Crown and the Palmaz-Schatz stent (PS153-series) were comparable. The spiral articulated Palmaz-Schatz stent showed twice the strength (1.26 atm) of ...

1998-06-01

293

Endovascular treatment of intrahepatic inferior vena cava obstruction from malignant hepatocellular tumor thrombus utilizing Luminexx self-expanding nitinol stents  

Energy Technology Data Exchange (ETDEWEB)

Inferior vena cava (IVC) obstruction is a well-described clinical entity. Most IVC obstructions from malignant neoplasms are a direct result of tumor compression [Oviedo J, Cerda S. Vascular invasion by hepatocellular carcinoma. Arch Pathol Lab Med 2001;125: 454-5; Furui S, Sawada S, et al. Gianturco stent placement in malignant caval obstruction: analysis of factors for predicting the outcome. Radiology 1995;195:147-52; Fletcher WS, Lakin PC, et al. Results of treatment of inferior vena cava syndrome with expandable metallic stents. Arch Surg 1998;133:935-8]. The symptoms of IVC obstruction include progressive ascites, scrotal edema and lower body edema. These constellations of symptoms are described as IVC syndrome and are devastating to a patient with end-stage cancer. We describe a palliative therapy utilizing Luminexx nitinol self-expanding stents to treat intracaval hepatoma thrombus obstructing the IVC. The procedure is rapidly performed, technically ...

2008-05-15

294

Data of spleen-scintiscanning after splenectomy  

International Nuclear Information System (INIS)

In 65 adult rabbits of both sexes (2.5 to 6 kg) the following salvaging procedures were performed after simulated trauma: (1) Continuous suture line; (2) closure with fibrin sealant after temporary clamping; (3) hemisplenectomy with omental wrap; (4) suture fixation of fragments and slices of spleen tissue to the peritoneum; (5) suture fixation of spleen fragments to the omentum; (6) extraperitoneal subcutaneous transposition of spleen cubes. In addition, the likelihood of spontaneous splenosis was examined in a preliminary study involving 5 animals by introducing unattached spleen meal and fragments. Scanning was repeated 4 to 12 weeks postoperatively. The functional competence of minor parenchymal islands was also investigated with well counter measurements of organ and muscle tissue homogenates. Spontaneous splenosis after abdominal injuries was not found to be the rule. Salvaging procedures at the natural vascular hilus by sutures, fibrin sealant and ...

295

Correlation of angiogenesis with "1"8F-FMT and "1"8F-FDG uptake in non-small cell lung cancer  

International Nuclear Information System (INIS)

L-[3-"1"8F]-#alpha#-methyltyrosine ("1"8F-FMT) is an amino-acid tracer for positron-emission tomography (PET). We have conducted a clinicopathologic study to elucidate the correlation of angiogenesis with "1"8F-FMT and 2-["1"8F]-fluoro-2-deoxy-D-glucose ("1"8F-FDG) uptake in patients with non-small cell lung cancer (NSCLC). Thirty-seven NSCLC patients were enrolled in this study, and two PET studies with "1"8F-FMT and "1"8F-FDG were performed. Uptake of PET tracers was evaluated with standardized uptake value. Vascular endothelial growth factor (VEGF), CD31, CD34, L-type amino acid transporter 1 (LAT1) and Ki-67 labeling index of the resected tumors were analyzed by immunohistochemical staining, and correlated with the clinicopathologic variables and the uptake of PET tracers. The median VEGF rate was 45% (range, 10-78%). High expression was seen in 30 patients (81%, 30/37). VEGF expression was statistically associated with progressively growing microvessel count. ...

2009-04-01

296

CF findings of bowel infarction in 56 surgical patients, 5 of whom with reversible ischemia; Aspetti alla tomografia computerizzata dell'infarto intestinale. 56 pazienti sottoposti a interventi chirurgico di cui 5 con ischemia mesenterica reversibile.  

Energy Technology Data Exchange (ETDEWEB)

Bowel infarction is a rare and typical condition of the elderly; despite improvements in diagnostic imaging and vascular surgery, bowel infarction remains a major cause of acute abdomen, with mortality rates ranging 70-80%. Diagnosis on often late because clinical signs, laboratory data and radiologic findings are a specific. The authors investigated radiographic and particular CT patterns of intestinal infraction in 56 patients submitted to surgery within 12 hours of admission. We also report the CT findings of 5 of these patients who had reversible mesenteric ischemia. CT is more sensitive than radiography and does not exhibit the limitations of angiography (i.e., invasiveness, radiation exposure and complex organization). Therefore CT can presently be considered the method of choice in patients with suspected bowel infarction. [Italian] L'infarto intestinale rappresenta una malattia rara e tipica del soggeto anziano; nonostante il notevole ...

1999-04-01

297

Basic fibroblast growth factor binds to subendothelial extracellular matrix and is released by heparitinase and heparin-like molecules  

Energy Technology Data Exchange (ETDEWEB)

Basic fibroblast growth factor (bFGF) exhibits specific binding to the extracellular matrix (ECM) produced by cultured endothelial cells. Binding was saturable as a function both of time and of concentration of {sup 125}I-bFGF. Scatchard analysis of FGF binding revealed the presence of about 1.5 x 10{sup 12} binding sites/mm{sup 2} ECM with an apparent k{sub D} of 610 nM. FGF binds to heparan sulfate (HS) in ECM as evidenced by (i) inhibition of binding in the presence of heparin or HS at 0.1-1 {mu}g/mL, but not by chondroitin sulfate, keratan sulfate, or hyaluronic acid at 10 {mu}g/mL, (ii) lack of binding to ECM pretreated with heparitinase, but not with chondroitinase ABC, and (iii) rapid release of up to 90% of ECM-bound FGF by exposure to heparin, HS, or heparitinase, but not to chondroitin sulfate, keratan sulfate, hyaluronic acid, or chondroitinase ABC. Oligosaccharides derived from depolymerized heparin, and as small as the tetrasaccharide, released the ECM-bound FGF, but there ...

1989-02-21

298

The technical-economic potential of thermal energy saving in hospitals; El potencial tecnico-economico de ahorro de energia termica en hospitales  

Energy Technology Data Exchange (ETDEWEB)

The hospitals are important consumers of energy. At the General Hospital of Zone (HGZ) N of the IMSS in Aguscalientes (HGZ N . IMSS Ags.), the diesel oil is the main fuel that is used to satisfy the requirements of thermal energy of the hospital. According to the data collected by this author, this fuel represented in 2001, 75% of its total energy consumption and the 67.9% of its total costs in energy that ascended to $396.131 (December 2001 Dollars) Since this last amount represents an important percentage of the total expenses of the hospital (29.367 million dollars) it is important to determine the technical-economic possibilities of thermal energy saving of the hospital. The HGZ N 1 IMSS Ags. is located in a ampler conglomerate where the IMSS units are located, such as, the regional laundry, the sport unit, the center of social security, the familiar medicine unit N 1 and the hospital. Nevertheless departing from the installation of the electrical systems and the provision of steam ...

2001-07-01

299

Incidence of Central Vein Stenosis and Occlusion Following Upper Extremity PICC and Port Placement  

Science.gov (United States)

The purpose of this study was to determine the incidence of central vein stenosis and occlusion following upper extremity placement of peripherally inserted central venous catheters(PICCs) and venous ports. One hundred fifty-four patients who underwent venography of the ipsilateral central veins prior to initial and subsequent venous access device insertion were retrospectively identified. All follow-up venograms were interpreted at the time of catheter placement by one interventional radiologist over a 5-year period and compared to the findings on initial venography. For patients with central vein abnormalities, hospital and home infusion service records and radiology reports were reviewed to determine catheter dwelltime and potential alternative etiologies of central vein stenosis or occlusion. The effect of catheter caliber and dwell time on development of central vein abnormalities was evaluated. Venography performed prior to initial catheter placement showed that 150 patients had ...

2003-04-15

300

Geochemical and petrographic properties of some Spitsbergen coals and dispersed organic matter  

Energy Technology Data Exchange (ETDEWEB)

This paper presents the characteristics of selected parameters of organic matter of the Tertiary coal samples and organic matter of Carboniferous rock samples from the Spitsbergen. The coal samples were taken from Central Coal Basin (the Longyearbyen region) and from the Forlandsundet Basin (Oscar II Land, the Kaffioyra region). Samples of dispersed organic matter were collected from Suffolk Pynten and Sergeijevfjellet area in Sorkapp Land. The optical properties of coal samples are different from properties of dispersed organic matter. Macerals of vitrinite group dominate in all of the samples. The average content of vitrinite group macerals is much lower in dipersed organic matter samples than it is in coals. The average content of liptinite group macerals is a little lower, and inertinite group macerals is much higher. The average content of mineral matter is higher in organic matter samples than in coal samples. The average value of vitrinite reflectance and standard deviation of ...

2004-02-20

301

Neutron beam experiments using nuclear research reactors: honoring the retirement of professor Bernard W. Wehring -I. 6. Neutronics Analyses for Beamline Upgrades to the High Flux Isotope Reactor  

International Nuclear Information System (INIS)

The High Flux Isotope Reactor (HFIR) located at Oak Ridge National Laboratory is one of the world's most powerful research reactors. In 1996, one year after the demise of the Advanced Neutron Source Project, the U.S. Department of Energy embarked on an aggressive program to upgrade the neutron scattering facilities at the HFIR. These upgrades, which are now in progress, include the installation of larger beam tubes, a high-performance hydrogen cold source, and additional neutron guides and neutron scattering instruments. An extensive analysis effort was performed over the past 4 yr to support the design of the modified beamlines and new user facilities and to assess the impact of the upgrades on the integrity of the existing reactor system. The results of three of these analyses are summarized here. Specifically, results are presented for analyses related to the design of the new cold neutron source (CNS), the assessment of beam tube changes on the anticipated pressure vessel lifetime, ...

2001-06-17

302

Geological evolution of the center-southern portion of the Guyana shield based on the geochemical, geochronological and isotopic studies of paleoproterozoic granitoids from southeastern Roraima, Brazil; Evolucao geologica da porcao centro-sul do escudo das Guianas com base no estudo geoquimico, geocronologico e isotopico dos granitoides paleoproterozoicos do sudeste de Roraima, Brasil  

Energy Technology Data Exchange (ETDEWEB)

This study focuses the granitoids of center-southern portion of Guyana Shield, southeastern Roraima, Brazil. The region is characterized by two tectonic-stratigraphic domains, named as Central Guyana (GCD) and Uatuma-Anaua (UAD) and located probably in the limits of geochronological provinces (e.g. Ventuari-Tapajos or Tapajos-Parima, Central Amazonian and Maroni-Itacaiunas or Transamazon). The aim this doctoral thesis is to provide new petrological and lithostratigraphic constraints on the granitoid rocks and contribute to a better understanding of the origin and geo dynamic evolution of Guyana Shield. The GCD is only locally studied near to the UAD boundary, and new geological data and two single zircon Pb-evaporation ages in mylonitic biotite granodiorite (1.89 Ga) and foliated hastingsite-biotite granite (1.72 Ga) are presented. These ages of the protholiths contrast with the lithostratigraphic picture in the other areas of Cd (1.96-1.93 Ga). Regional mapping, petrography, ...

2006-07-01

303

Fifteen years of seismic monitoring at the Las Tres Virgenes, BCS, geothermal field; Quince anos de monitoreo sismico en el campo geotermico de Las Tres Virgenes, BCS  

Energy Technology Data Exchange (ETDEWEB)

Seismic monitoring at the Las Tres Virgenes, BCS, geothermal field started in 1992 with an analog station of vertical components detecting a large number of earthquakes of varying magnitudes. In February 1993, a seismic network was installed, composed of six digital stations DR-2000-with S-6000 and S-5000 sensors and three registration channels (N-S, E-W and vertical). This was the basis for the development of a program to correct arrival-time data for P and S waves due to instrument drift. From January to April 1994 and May to August 1995, based on the 170 seismic events recorded, a velocity model was proposed. From December 1995 to July 1996, seismic data were processed and interpreted, and zones of occurrence were determined for events according to magnitude and the predominant noise in the field. From September 2003 to December 2004, 10 seismic stations (permanent and temporary) were installed and monitored and it was concluded the most active fault system was El Volcan. From ...

2009-07-15

304

Poly-lactic-acid coating of endovascular stents: preliminary results in canine experimental av-fistulae  

Energy Technology Data Exchange (ETDEWEB)

Poly-Lactic-Acid (PLA) was evaluated for coating of vascular endoprotheses in the treatment of experimental arterio-venous-fistulae (AVF). Bilateral carotid-external jugular AVF were created in 5 adult dogs. 7 PLA coated nitinol stents were placed via a transfemoral approach covering 5 AVF. The contralateral AVF remained untreated. Angiography was performed immediately after stent placement, at weeks 1 and 3 and at months 3, 6 and 9. All grafts were removed and underwent histologic examination. In 2 cases the occlusion of the AVF was successful, while misplacement occurred in 3 cases. Occlusion of the parent vessel was disclosed in 3 cases. Histologic examination revealed a mild inflammatory reaction with the presence of macrophages. There was no foreign-body reaction or fragmentation of the arterial vessel wall. PLA, which is a well-known biodegradable material, showed a good mid-term biocompatibility. Elastic mismatch of the non-elastic coating and the ...

2001-02-01

305

Multiphasic helical CT of hepatocellular carcinoma. Evaluation after chemoembolization; Tomografia Computerizzata spirale multifasica dell'epatocarcinoma. Valutazione dopo chemioembolizzazione  

Energy Technology Data Exchange (ETDEWEB)

The main purpose of this work is to report the personal experience with addition of contrast-enhanced multiphase helical CT to unenhanced CT (Lipiodol CT) in the evaluation of patients with hepatocellular carcinoma treated with chemoembolization and to analyze the present role of oily agent CT. It has been retrospectively reviewed the examinations of 42 consecutive patients submitted to global chemoembolization over a 2-year period. CT was performed 18-30 days after the treatment. The Lipiodol CT study was carried out with volume acquisitions. It has been considered as nodules all well-defined areas with dense oily agent uptake; uptake itself was classified as: 0=absent, I=lower than 10% of the tumor volume; II=lower than 50%, III=50%, IV=homogeneous. Contrast-enhanced helical CT was performed with the 2-phase technique in 28 patients and with the 3-phase technique in 14; it has been considered as nodules all well-defined and relatively homogeneous areas with hyper attenuation in the ...

2000-06-01

306

Computed Tomography of the diabetic kidney; La Tomografia Computerizzata nello studio del rene diabetico  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this work is to investigate whether any morphometric or densitometric are detectable in the kidneys of type 2 diabetic patients. 40 diabetic patients were examined and of 20 non-diabetics (the control group) were submitted to triphasic helical CT for different abdominal conditions. The type 2 diabetic patients were 23 men and 17 women, mean age 62 years, while the nondiabetic controls were 12 men and 8 women, mean age 58 years. All the CT images were analyzed using the Multiplanar Reconstruction (MPR) software. It was evaluated morphometric features, such as the presence of parenchymal or vascular calcifications, axial and coronal renal diameters, coronal renal area, and cortico medullary ratio, and densitometric and functional features, such as unenhanced renal density, cortical and medullary density in the arterial phase, parenchymal density in the nephrographic phase, and contrast elimination. It was also compared the results in the subgroups of ...

2000-02-01

307

CT and MRI characteristica of tumours of the temporal bone and the cerebello-pontine angle; CT und MRT tumoroeser Veraenderungen des Schlaefenbeins  

Energy Technology Data Exchange (ETDEWEB)

Tumours lesions of the temporal bone and of the cerebello-pontine angle are rare.This tumours can be separated into benign and malignant lesions. In this paper the CT and MRI characteristica of tumours of the temporal bone and the cerebello-pontane angle will be demonstrated. High resolution CT (HRCT) as usually performed in the axial plane are using a high resolution bone window level setting, coronal planes are the reconstructed from the axial data set or will be obtained directly. With the MRI FLAIR sequence in the axial plane the whole brain will be scanned either to depict or exclude a tumour invasion into the brain. After this,T2-weighted fast spin echo sequences or fatsuppressed inversion recovery sequences in high resolution technique in the axial plane will be obtained from the temporal bone and axial T1-weighted spinecho sequences before and after the intravenous application of contrast material will be obtained of this region. Finally T1-weighted spinecho sequences in high ...

2003-03-01