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Sample records for magnetisk resonans billeddannelse

  1. Magnetisk resonans billeddannelse af dissemineret sklerose

    DEFF Research Database (Denmark)

    Christiansen, A P; Wanscher, B; Larsson, H B

    1994-01-01

    Gadolinium-DTPA, it is possible to distinguish a newly developed plaque from an older one. Therefore, MRI has become an important examination in therapeutic trials. Just now, MRI with Gadolinium-DTPA is being used to evaluate the efficacy of plasmapheresis and immunoglobulin treatment in a joint study...

  2. Praeoperativ funktionel magnetisk resonans-billeddannelse hos patienter med hjernetumor

    DEFF Research Database (Denmark)

    Laustsen, Søren Ravn; Meulengracht Sørensen, Preben; Fründ, Torben

    2010-01-01

    MRI plus a three-month postoperative assessment. A total of 14 patients complied with these requirements (six men and eight women, the mean age was 39 years). fMRI raw data was collected using a three tesla magnetic resonance scanner (Signa HDx R14M5, GE Healthcare). The distance from the tumour margin...

  3. Praeoperativ funktionel magnetisk resonans-billeddannelse hos patienter med hjernetumor

    DEFF Research Database (Denmark)

    Laustsen, Søren Ravn; Sørensen, Preben; Fründ, Torben

    2010-01-01

    deficits by means of a standardised method for measurement of distance. A second purpose was to investigate the influence of preoperative fMRI on the neurosurgical decision-making process. MATERIAL AND METHODS: Retrospective study of 25 patients. The inclusion criteria were surgery or biopsy after f...... to fMRI activation was measured using GE-reformat version 4.2 after raw data had been postprocessed using GE BrainwavePA version 1.3.08130. The neurosurgeons valuation of fMRI in the preoperative decision-making process was obtained using a standard questionnaire. RESULTS: There was a trend......%) and when deciding the extent of the surgical approach (83%). CONCLUSION: The standardised method for measurement of distance between tumour margin and fMRI activity can contribute to the preoperative risk assessment in patients with brain tumours....

  4. Praeoperativ funktionel magnetisk resonans-billeddannelse hos patienter med hjernetumor

    DEFF Research Database (Denmark)

    Laustsen, Søren Ravn; Meulengracht Sørensen, Preben; Fründ, Torben

    2010-01-01

    deficits by means of a standardised method for measurement of distance. A second purpose was to investigate the influence of preoperative fMRI on the neurosurgical decision-making process. MATERIAL AND METHODS: Retrospective study of 25 patients. The inclusion criteria were surgery or biopsy after f...... to fMRI activation was measured using GE-reformat version 4.2 after raw data had been postprocessed using GE BrainwavePA version 1.3.08130. The neurosurgeons valuation of fMRI in the preoperative decision-making process was obtained using a standard questionnaire. RESULTS: There was a trend...... (50%) and when deciding the extent of the surgical approach (83%). CONCLUSION: The standardised method for measurement of distance between tumour margin and fMRI activity can contribute to the preoperative risk assessment in patients with brain tumours....

  5. Præoperativ funktionel magnetisk resonans-billeddannelse hos patienter med hjernetumor

    DEFF Research Database (Denmark)

    Laustsen, Søren Ravn; Sørensen, Preben; Fründ, Torben

    2010-01-01

    MRI plus a three-month postoperative assessment. A total of 14 patients complied with these requirements (six men and eight women, the mean age was 39 years). fMRI raw data was collected using a three tesla magnetic resonance scanner (Signa HDx R14M5, GE Healthcare). The distance from the tumour margin...

  6. Præoperativ funktionel magnetisk resonans-billeddannelse hos patienter med hjernetumor

    DEFF Research Database (Denmark)

    Laustsen, Søren Ravn; Sørensen, Preben; Fründ, Torben;

    2010-01-01

    MRI plus a three-month postoperative assessment. A total of 14 patients complied with these requirements (six men and eight women, the mean age was 39 years). fMRI raw data was collected using a three tesla magnetic resonance scanner (Signa HDx R14M5, GE Healthcare). The distance from the tumour margin...

  7. Helkrops magnetisk resonans-angiografi

    DEFF Research Database (Denmark)

    Nielsen, Y.W.; Moller, J.M.; Thomsen, Henrik S.

    2008-01-01

    Whole-body magnetic resonance angiography (WB-MRA) is a new approach for diagnosing atherosclerosis. Through utilisation of fast whole-body MRI systems, the arterial system, excluding the intracranial and coronary arteries, can be investigated in one examination. WB-MRA has the potential of repla...... of replacing conventional catheter-based angiography in the diagnostic workup of patients with atherosclerotic disease. Developments in MRI contrast agents and MRI systems may further improve WB-MRA Udgivelsesdato: 2008/8/18......Whole-body magnetic resonance angiography (WB-MRA) is a new approach for diagnosing atherosclerosis. Through utilisation of fast whole-body MRI systems, the arterial system, excluding the intracranial and coronary arteries, can be investigated in one examination. WB-MRA has the potential...

  8. Magnetisk resonans-skanning af det kvindelige baekken

    DEFF Research Database (Denmark)

    Marinovskij, Edward; Kazlauskaite, Ramune; Dueholm, Margit;

    2008-01-01

    The use of magnetic resonance (MR) imaging of the female pelvis has expanded considerably over the past decade. We here review important indications, including congenital anomalies, benign and malignant diseases and special emphasis is given to the diagnostic value and possible limitations of MR...

  9. Anaestesimonitorering ved magnetisk resonans undersøgelser

    DEFF Research Database (Denmark)

    Garde, K; Sørensen, M B; Boelt, P

    1992-01-01

    render possible investigation of unconscious or anaesthetized patients in scanners with magnetic fields of over 1.5 Tesla. The medical technical difficulties involved are mentioned and the solutions which are employed in the Danish scientific Centre for Magnetic Resonance in Hvidovre Hospital...

  10. Magnetisk resonans-skanning til praeoperativ stadieinddeling af cancer recti

    DEFF Research Database (Denmark)

    Mortensen, Line Aas; Leffers, Anne-Mette; Holck, Susanne;

    2009-01-01

    INTRODUCTION: The treatment of rectum cancer depends on the tumour stage, and until 2005 treatment included preoperative radiation therapy for the T3 and T4 cancer stages. An exact preoperative assessment of the cancer stage is therefore essential. In Denmark rectal Magnetic Resonance Imaging (MRI......% of the cancers were understaged (15% of T3 tumours, 67% of T4 tumours). The selection of patients for preoperative radiation therapy had a sensitivity and specificity of 83% and 48%, respectively. CONCLUSION: The overall accuracy of 58% indicates that MR imaging in the early learning phases was not an optimal...

  11. Maling af myokardieperfusion med magnetisk resonans-skanning

    DEFF Research Database (Denmark)

    Henriksen, O.M.; Fritz-Hansen, T.; Jensen, L.T.;

    2008-01-01

    Cardiac magnetic resonance imaging (MRI) has evolved rapidly. Recent developments have made non-invasive quantitative myocardial perfusion measurements possible. MRI is particularly attractive due to its high spatial resolution and because it does not involve ionising radiation. This paper review...... myocardial perfusion imaging with MR contrast agents: methods, validation and experiences from clinical studies. Unresolved issues still restrict the use of these techniques to research although clinical applications are within reach Udgivelsesdato: 2008/12/8......Cardiac magnetic resonance imaging (MRI) has evolved rapidly. Recent developments have made non-invasive quantitative myocardial perfusion measurements possible. MRI is particularly attractive due to its high spatial resolution and because it does not involve ionising radiation. This paper reviews...

  12. Magnetisk resonans-imaging (MRI)-styret fokuseret ultralyd

    DEFF Research Database (Denmark)

    Salomir, Rares; Hokland, S.; Pedersen, M.

    2005-01-01

    demonstrated with this unique technology, and based on these experiments the combination of focussed ultrasound and MRI thermometry holds promise for future oncological diagnostics and treatment. In this paper we review some of the recent methodological developments as well as experimental and first clinical...

  13. Magnetisk resonans og multipel sklerose. II. Nye diagnostiske metoder

    DEFF Research Database (Denmark)

    Mathiesen, Henrik Kahr; Langkilde, Annika Reynberg; Larsson, Henrik B W

    2002-01-01

    Conventional magnetic resonance imaging (MRI) techniques have proved important in the diagnosis and in the follow-up in clinical trials of patients with multiple sclerosis (MS). However, these techniques have low specificity for the pathological changes in the MS lesions, and the correlation...

  14. Magnetisk resonans og multipel sklerose. I. Konventionelle diagnostiske metoder

    DEFF Research Database (Denmark)

    Mathiesen, Henrik Kahr; Langkilde, Annika Reynberg; Larsson, Henrik B W

    2002-01-01

    Conventional magnetic resonance imaging (MRI) is still the standard technique in the diagnosis and follow-up of patients with multiple sclerosis (MS), despite low pathological specificity and poor correlation to the disability. The results of T2- and T1-weighted imaging with and without contrast...

  15. Sikkerhed af magnetisk resonans-skanning hos patienter med pacemaker og implanterbar defibrillator

    DEFF Research Database (Denmark)

    Al-Sabagh, Kifah Hekmat; Christensen, Britta Ege; Thøgersen, Anna Margrethe;

    2010-01-01

    INTRODUCTION: The presence of a cardiac implantable device is ICD considered an absolute contraindication to magnetic resonance imaging (MRI). The purpose of this study was to evaluate the safety of performing MRI in patients with cardiac pacemakers and ICDs that had a compelling clinical need...

  16. Magnetisk resonans sondering i grundvattenprospektering, med tillämpningar i Laos och Sverige

    OpenAIRE

    2011-01-01

    Water is essential for all life on the planet, sustaining and ensuring the earth’s ecosystem. Groundwater from a global perspective provides about 50 % of the potable water, 40 % of the industrial water and 20 % of the irrigation water. For drinking water, deep groundwater has many advantages compared to surface water and shallow groundwater, since it demands little or no treatment and the access is secured against temporary droughts. However, drilling wells for deep groundwater is expensive ...

  17. Julestemningens cerebrale repræsentation – et tværkulturelt, funktionelt magnetisk resonans-studie

    DEFF Research Database (Denmark)

    Amin, Faisal Mohammad; Lindberg, Ulrich; Raghava, Jayachandra Mitta

    2012-01-01

    INTRODUCTION: Functional magnetic resonance imaging has been used to detect specific cognitive functions of the human brain. To our knowledge, no attempt has yet been made to localize the Christmas spirit using this technique. MATERIAL AND METHODS: We used a 3 tesla MR scanner and a visual...... associated stimulation comprising frontal, parieto-occipital and subcortical areas. In the control group we found a small response limited to visual association areas. DISCUSSION: Christmas-associated cerebral activation comprises a network involving areas of sensory, motor and emotional processing....... The applied method is appropriate for the detection of Christmas-related areas of the brain but the results of the study should be verified in a larger sample size....

  18. Magnetisk resonans-arteriografi i perifer karkirurgi. En ny og ikke-invasiv metode til visualisering af arterier

    DEFF Research Database (Denmark)

    Eiberg, Jonas P; Lundorf, Erik; Thomsen, Carsten;

    2002-01-01

    and pose fewer problems. The sensitivity and specificity of TOF-MRA are 93% (range 64-100%) and 88% (range 57-100%) respectively, and that of CE-MRA 96% (range 71-100%) and 96% (63-100%), respectively, with conventional arteriography as the gold standard. Some studies report an incidence of run-off vessels...

  19. Magnetic resonance tomography of the heart; Magnetisk resonanstomografi av hjertet

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Hans-Joergen

    2000-07-01

    Magnetic resonance imaging is a rarely performed procedure in cardiac disease, mainly due to easily available alternative techniques, especially echocardiography. MR imaging may, however, provide unique anatomical and functional information and represents a valuable supplement to the alternative invasive and non-invasive modalities. Clinical indications for MR imaging of the heart include congenital heart disease, acute and chronic ischaemic hart disease, valvular hear disease, cardiomyopathy, right ventricular dysplasia, pericardial disease and cardiac tumours. In the near future, MR imaging may provide a complete ''non-stop'' evaluation of cardiac disease.

  20. Multiple tarmperforationer efter indtagelse af magnetisk legetøj

    DEFF Research Database (Denmark)

    Carlsen, Charlotte Green; Floyd, Andrea K; Lundhus, Eskild

    2007-01-01

    Ingestion of small foreign bodies is common in children, and usually does not cause any harm to the gastrointestinal tract. But ingestion of multiple magnets can be hazardous because of the strong attraction of the magnets through the bowel wall, which may lead to bowel wall necrosis...

  1. Musik og billeddannelse (GIM med PTSD-ramte flygtninge: Introduktion til tre single case-studier

    Directory of Open Access Journals (Sweden)

    Bolette Daniels Beck

    2016-12-01

    Full Text Available Mange flygtninge kommer fra kulturer med helt andre forestillinger og begreber om årsager til og forventninger om behandling af psykisk lidelse end man almindeligvis anvender i psykiatrien. F.eks. er psykisk lidelse i mange mellemøstlige kulturer forbundet med skam, og udtrykkes måske derfor snarere i form af fysisk smerte. For at et behandlingsforløb skal lykkes, er der behov for kulturel sensitivitet hos behandleren, når der skal samarbejdes med tolken, skabes et møde på tværs af kulturer samt etableres en fælles forståelse af behandlingens formål og proces.

  2. Molekylaer billeddannelse med positronemissionstomografi og single photon emission computer tomography. Status og perspektiver

    DEFF Research Database (Denmark)

    Kjaer, Andreas

    2005-01-01

    Molecular imaging allows for the study of molecular and cellular events in the living intact organism. The nuclear medicine methodologies of PET and SPECT possess several advantages which make them especially suited for molecular imaging. In particular, the possibility of a quick transfer of meth...

  3. Resonanant enhancement of molecular excitation intensity in inelastic electron scattering spectrum owing to interaction with plasmons in metallic nanoshell

    CERN Document Server

    Goliney, I Yu

    2014-01-01

    A quantum-mechanical model to calculate the electron energy-loss spectra (EELS) for the system of a closely located metallic nanoshell and a molecule has been developed. At the resonance between the molecular excitation and plasmon modes in the nanoshell, which can be provided by a proper choice of the ratio of the inner and outer nanoshell radii, the cross-section of inelastic electron scattering at the molecular excitation energy is shown to grow significantly, because the molecular transition borrows the oscillator strength from a plasmon. The enhancement of the inelastic electron scattering by the molecule makes it possible to observe molecular transitions with an electron microscope. The dependences of the EEL spectra on the relative arrangement of the molecule and the nanoshell, the ratio between the inner and outer nanoshell radii, and the scattering angle are plotted and analyzed.

  4. Resonanant enhancement of molecular excitation intensity in inelastic electron scattering spectrum owing to interaction with plasmons in metallic nanoshell

    OpenAIRE

    Goliney, I. Yu.; Onykienko, Ye. V.

    2014-01-01

    A quantum-mechanical model to calculate the electron energy-loss spectra (EELS) for the system of a closely located metallic nanoshell and a molecule has been developed. At the resonance between the molecular excitation and plasmon modes in the nanoshell, which can be provided by a proper choice of the ratio of the inner and outer nanoshell radii, the cross-section of inelastic electron scattering at the molecular excitation energy is shown to grow significantly, because the molecular transit...

  5. Dynamical Coupled-Channel Model of pi-N scattering in te W < 2 GeV Nucleon Resonane Region

    Energy Technology Data Exchange (ETDEWEB)

    Lee, T S.H.; Julia-diaz, B; Matsuyama, A; Sato, T

    2007-12-01

    As a first step to analyze the electromagnetic meson production reactions in the nucleon resonance region, the parameters of the hadronic interactions of a dynamical coupled-channel model, developed in {\\it Physics Reports 439, 193 (2007)}, are determined by fitting the empirical $\\pi N$ elastic scattering amplitudes of SAID up to 2 GeV. The channels included in the calculations are $\\pi N$, $\\eta N$ and $\\pi\\pi N$ which has $\\pi\\Delta$, $\\rho N$, and $\\sigma N$ resonant components. The non-resonant meson-baryon interactions of the model are derived from a set of Lagrangians by using a unitary transformation method. One or two bare excited nucleon states in each of $S$, $P$, $D$, and $F$ partial waves are included to generate the resonant amplitudes in the fits. The predicted total cross sections of $\\pi N$ reactions and $\\pi N\\rightarrow \\eta N$ reactions are in good agreement with the data. Applications of the constructed model in analyzing the electromagnetic meson production data as well as the future developments are discussed.

  6. Planar Hall Sensor for Influenza Immunoassay

    DEFF Research Database (Denmark)

    Ejsing, Louise Wellendorph

    2006-01-01

    følsomt kan detektere magnetiske nanokugler. Indledende biodetektionsforsøg rettet mod detektion af influenza-virus blev udført i samarbejde med Statens Serum-Institut. Det blev demonstreret, at sensorerne har et stort potentiale til biodetektion men også at den uspecifikke binding af magnetiske kugler...

  7. Musiklytning og indre billeder

    DEFF Research Database (Denmark)

    Bonde, Lars Ole; Pedersen, Inge Nygaard

    2012-01-01

    Kan lytning og indre billeddannelse til udvalgt klassisk musik være en effektiv gruppeterapiform for ambulante psykiatriske patienter? Med henblik på at besvare dette spørgsmål deltog 12 ambulante patienter i årene 2008-10 i 9 gruppeforløb (2-4 deltagere per gruppe; enkeltpersoner kunne deltage i...

  8. Dansk sekretær i DAC

    DEFF Research Database (Denmark)

    Andersen, Jens Enevold Thaulov

    2007-01-01

    Ved den første Europæiske kongres for kemi i Budapest sidste år, var analytisk kemi officielt kun repræsenteret gennem emnet analytisk kemi med billeddannelse. Deltagerantallet til den analytisk-kemiske del var meget begrænset, og langt under det forventede niveau. I år blev den 14. kongres i ana...

  9. Fleksibel undervisningsmodel for røntgenfysik på modul 2

    DEFF Research Database (Denmark)

    Vernegreen, Susanne; Outzen, Claus Bjørn

    2013-01-01

    Faget radiografisk billeddannelse (RB) introduceres med 36 timers røntgenfysik. De studerende har meget forskellige forudsætninger i denne disciplin. Det faglige niveau i fysik spænder fra A-G. Der er derfor behov for et tiltag, der kan imødekomme denne udfordring Differentieret undervisning genn...

  10. Diffusion-weighted magnetic resonance imaging - a new instrument in the diagnosis of Creutzfeldt-Jacob's disease; Diffusjonsvektet magnetisk resonanstomografi - nytt i diagnostikken av Creutzfeldt-Jakobs sykdom

    Energy Technology Data Exchange (ETDEWEB)

    Romi, Fredrik; Smivoll, Alf Inge; Moerk, Sverre; Tysnes, Ole-Bjoern

    2000-07-01

    Creutzfeldt-Jacob's disease (CID) is characterised by rapidly progressive dementia, ataxia, myoclonus and several other neurological deficits. It generally affects older adults and occurs in sporadic, genetic and iatrogenic forms. Death occurs usually within one year after onset of the disease. The diagnosis is based on clinical criteria, neuro physiological and radiological findings and confirmed by post mortal histopathology. During the last two years several cases of CID have been reported with diffusion-weighted magnetic resonance imaging (MR) abnormalities represented by increased signal intensity indicating reduced diffusion in basal ganglia and/or cortex cerebric. These abnormalities seem to be characteristic of CID. We report a case of CID in a 54 year old woman who developed vertigo, nystagmus, ataxia, myoclonus and dementia over a period of eight months. Diffusion-weighted magnetic resonance imaging showed increased signal intensity in corpus striatum and gyrus conguli. The diagnosis was post mortally confirmed with histopathology. (Author) 7 figs., 15 refs.

  11. Advances in high-gradient magnetic fishing for bioprocessing

    OpenAIRE

    Goncalves Gomes, Claudia Sofia; Hobley, Timothy John

    2006-01-01

    “High-gradient magnetic fishing” (HGMF) er en metode til processering af fødestrømme med biologiske molekyler. HGMF integrerer brugen af superparamagnetiske adsorbenter med separation og processering med høj-gradient magnetisk separation (HGMS) i et magnetisk filter. Adsorbenterne er uporøse og meget små, hvilket tilsikrer en stor specifik bindingsoverflade. Siden sin begyndelse i 2001, har forskning indenfor HGMF fokuseret på undersøgelse af teknikkens basale principper og udbredelse af dens...

  12. Active magnetic regenerator refrigeration with rotary multi-bed technology

    OpenAIRE

    2016-01-01

    Magnetisk køling er en spirende køleteknologi med potentielle fordele frem for konventionel kompressor-baseret køling, med høj effektivitet som den vigtigste. I denne afhandling præsenteres eksperimentel og teoretisk forskning angående mulighederne for at realisere dette potentiale med aktive magnetiske regenerator (AMR) prototyper. Udgangspunktet er konstruktionen af og eksperimenter med en roterende multibed prototype ved Danmarks Tekniske Universitet. Lovende resultater blev opnåede med de...

  13. The utilization of BSA-modified chip on the investigation of ligand ...

    African Journals Online (AJOL)

    Administrator

    2009-12-15

    Dec 15, 2009 ... ... (NSB) of proteins. Key words: Surface plasmon resonance, bovine serum albumin, glutathione, ... the potential application of surface plasmon resonan- .... Schematic diagram of surface modification of BSA biochip with GSH.

  14. The magnetic properties of antiferromagnetic nanoparticles: NiO and -Fe2O3

    DEFF Research Database (Denmark)

    Bahl, Christian Robert Haffenden

    2006-01-01

    Nikkel oxid (NiO) og hematit -Fe2O3) er begge antiferromagneter med magnetiske egenskaber på nanoskala, som er forskellige fra dem i større krystaller. Med hovedvægt på nanopartikler af NiO og sammenligninger med nanopartikler af hematit studeres disse magnetiske egenskaber med en række...... egenskaber. Nanopartiklerne af NiO vises at være pladeformede med (111) planer som flader, en tykkelse på omkring 2.3 nm og en diameter på omkring 13 nm. Den magnetiske struktur er magen til den i større krystaller, med spinene holdt i (111) planerne. Målinger af spindynamikken afslører en værdi af den...... morter med hånden. Nanopartikler af antiferromagnetiske materialer vil have et ukompenseret magnetisk moment, der opstår ved endelige partikelstørrelser på grund af overskydende spin på det ene undergitter. Dette ukompenserede moment kvantiseres i NiO nanopartiklerne og findes at være uafhængigt af...

  15. Nanoparticles of antiferromagnetic materials

    DEFF Research Database (Denmark)

    Madsen, Daniel Esmarch

    2008-01-01

    I denne Ph.D. afhandling studeres forskellige egenskaber ved antiferromagnetiske nanopartikler. I en ideel antiferromagnet er spinnene orienteret således at der ikke er et resulterende magnetisk moment. I nanopartikler af antiferromagnetiske materialer er denne kompensation på grund af forskellig...

  16. Magnetisme i LDH og produktene etter dekomposisjon

    OpenAIRE

    Glesne, Erik

    2015-01-01

    Oppgaven omfatter studier av strukturelle og magnetiske egenskaper til materialer med lagdelt struktur i klassen lagdelte dobbelthydroksider (LDH). LDHer er lagdelte leirematerialer der det sitter vann og ladningsbalanserende anioner mellom lagene. Mange ulike kombinasjoner kationer med ulik ladning kan danne lagene, og LDHer har derfor en rekke interessante potensielle bruksområder. Dette omfatter blant annet multifunksjonelle nanokompositter med både polymerer og andre lagdelte strukturer i...

  17. Advances in high-gradient magnetic fishing for bioprocessing

    DEFF Research Database (Denmark)

    Goncalves Gomes, Claudia Sofia

    2006-01-01

    “High-gradient magnetic fishing” (HGMF) er en metode til processering af fødestrømme med biologiske molekyler. HGMF integrerer brugen af superparamagnetiske adsorbenter med separation og processering med høj-gradient magnetisk separation (HGMS) i et magnetisk filter. Adsorbenterne er uporøse og...... meget små, hvilket tilsikrer en stor specifik bindingsoverflade. Siden sin begyndelse i 2001, har forskning indenfor HGMF fokuseret på undersøgelse af teknikkens basale principper og udbredelse af dens anvendelighed til direkte produktfangst - med det langsigtede mål at udvikle et egentligt redskab til...... afhandling har været at undersøge, hvorledes HGMF kan anvendes til direkte fangst af højværdi produkter i fødestrømme ved høje koncentrationer, og hvorvidt HGMF kan udbredes til brug ved andre bioprocesseringsopgaver end direkte fangst, samt at besvare fundamentale spørgsmål om, hvorledes magnetiske...

  18. Ingestible capsule for remote controlled release of a substance

    DEFF Research Database (Denmark)

    2014-01-01

    The application relates to an ingestible capsule (102) for delivery of a substance e.g. a pharmaceutical drug, to a human or animal. The ingestible capsule comprises a capsule wall structure (202) forming a substantially sealed reservoir or lumen holding the substance (204). An electrical resonan...

  19. Interactions between Barley a-Amylases, Substrates, Inhibitors and Regulatory Proteins

    DEFF Research Database (Denmark)

    Hachem, Maher Abou; Bozonnet, Sophie; Willemoës, Martin

    2006-01-01

    Barley a-amylase binds sugars at two sites on the enzyme surface in addition to the active site. Crystallography and site-directed mutagenesis highlight the importance of aromatic residues at these surface sites as demonstrated by Kd values determined for ß-cyclodextrin by surface plasmon resonan...

  20. Changes in cerebral activations during movement execution and imagery after parietal cortex TMS interleaved with 3T MRI

    NARCIS (Netherlands)

    de Vries, Paulien M.; de Jong, Bauke M.; Bohning, Daryl E.; Walker, John A.; George, Mark S.; Leenders, Klaus L.

    2009-01-01

    The left parietal cortex contributes to goal-directed hand movement. In this study, we targeted this region with transcranial magnetic stimulation (TMS) to assess the effects on a wider distributed circuitry related to motor control. Ten healthy subjects underwent 3 Tesla functional magnetic resonan

  1. Development of a fluorine-free chemical solution deposition route for rare-earth cuprate superconducting tapes and its application to reel-to-reel processing

    OpenAIRE

    Tang, Xiao; Grivel, Jean-Claude

    2013-01-01

    Grundet nul modstand og ingen elektrisk energitab under el transmission, vil applikationen af superledere kunne levere en betydelig fordel, særligt taget den hurtige udvikling i betragtning på bekostning af høje energipriser. For operation ved flydende kvælstof temperatur, har REBCO visse fordele i at kunne bibeholde en høj strømningsdensitet under et stærkt magnetisk felt, således har REBCO højtemperatur superledere højt potentiale inden for højfelts tekniske applikationer.Sammenlignet med P...

  2. Controlling Interacting Systems in Noisy Environments

    Science.gov (United States)

    2010-10-06

    ratios of the partial work variance to mean partial work for fluctuations about periodic attractors of a resonantly modulated Duffing oscillator , as...resonan ly modulated Duffing oscillator , as functions of the reduced squared modulation amplitude β. The curves 1 and 2 refer to large- and small...modulated oscillator Authors: D. Ryvkine and M. I. Dykman, Source: Phys. Rev. E 74, 061118 (2006) Disease extinction in the presence of non-Gaussian

  3. Negative refraction by a virtual photonic lattice

    OpenAIRE

    Budko, Neil V.; Raghunathan, Shreyas B.

    2008-01-01

    Research on photonics and metamaterials constantly challenges our intuitive understanding of the behaviour of light. In recent years we have seen negative refraction, focusing of light by a flat slab, a ``perfect'' prism, and an ``invisibility cloak'' [1-6]. It is generally understood that the cause of this unusual behaviour is the strong (anomalous) dispersion, i.e., dependence of the material properties on the frequency of light. Dispersion can be either due to a natural microscopic resonan...

  4. Mesoporous Silica Nanoparticles with Co-Condensed Gadolinium Chelates for Multimodal Imaging

    OpenAIRE

    Wenbin Lin; Joseph Della Rocca; Kathryn M. L. Taylor-Pashow

    2011-01-01

    Several mesoporous silica nanoparticle (MSN) contrast agents have been synthesized using a co-condensation method to incorporate two different Gd3+ complexes at very high loadings (15.5–28.8 wt %). These MSN contrast agents, with an MCM-41 type pore structure, were characterized using a variety of methods including SEM and TEM, nitrogen adsorption measurements, thermogravimetric analysis (TGA), direct current plasma (DCP) spectroscopy, and powder X-ray diffraction (PXRD). The magnetic resonan...

  5. Utilidad de la resonancia magnética testicular con espectroscopía en el análisis cuantitativo de la infertilidad

    OpenAIRE

    Baleato González, Sandra

    2012-01-01

    PURPOSE: To determine the role of MRI and MR spectroscopy (MRSI) in the diagnosis of infertility. To stablish normal values of the metabolites involved in the spermatogenesis (choline, creatine, and lipids) and to quantify the infertility and describe their causes by combining these values. MATERIAL AND METHODS: This study included 27 consecutive patients attending the urologist 24 with fertility problems and 3 healthy patients. A total of 50 testes were evaluated at 1.5T magnetic resonan...

  6. Scaling-up ultrasound standing wave enhanced sedimentation filters

    OpenAIRE

    Prest, Jeff E.; Treves Brown, Bernard J.; Fielden, Peter R.; Wilkinson, Stephen J.; Hawkes, Jeremy J.

    2015-01-01

    Particle concentration and filtration is a key stage in a wide range of processing industries and also one that can be present challenges for high throughput, continuous operation. Here we demonstrate some features which increase the efficiency of ultrasound enhanced sedimentation and could enable the technology the potential to be scaled up. In this work, 20 mm piezoelectric plates were used to drive 100 mm high chambers formed from single structural elements. The coherent structural resonan...

  7. Investigation of the Optical, Electronic, and Structural Properties of Fiber Optic Glasses

    Science.gov (United States)

    1993-06-01

    concentration measured by electron paramagnetic resonan, e) and Nd ( calibration curve using dope fractioning) as standards. The photoluminescent intensity of...phonon peak position at 13 3 3.30 cm- and FWHM of 3.00 cmŕ .For calibration and comparison. we had peoroand high msolution RS measurement (bandpass - M...DC 20375-500 $achslFreeman Associates, Landover, MD 20785-539% :-.nivmt ofIlinosUrbana-Campaign. Urbana. EL 61301 ABSTRACT Photolumi’nescence specto

  8. Resonances in the System of Pi+Pi- -- Mesons from the Reaction np->npPi+Pi- at Pn=5.20GeV/c: Search, Results of Direct Observations, Interpretation

    OpenAIRE

    Troyan, Yu. A.; Plekhanov, E. B.; Pechenov, V. N.; Troyan, A. Yu.; Beljaev, A. V.; Jerusalimov, A. P.; Aracelian, S. G.

    2004-01-01

    Ten resonances were found in the mass spectrum of pi+pi- -system from the reaction np->nppi+pi- in np-interactions at Pn=5.20 GeV/c in the 1-m HBC of LHE JINR by using the criterion cos(teta)[c.m.c.] p>0. Such effects were not found in pi-pi0 - combinations from the reaction np->pppi-pi0. Therefore, it is necessary to attribute the value of isotopic spin I = 0 to the resonances found in the mass spectrum of the pi+pi- -system. The spin was estimated for the most statistically provided resonan...

  9. Optical Sensors based on Raman Effects

    DEFF Research Database (Denmark)

    Jernshøj, Kit Drescher

    Formålet med denne afhandling er at give en systematisk og uddybende videnskabelig diskussion af molekylær Raman spredning, som kan danne grundlag for udviklingen af molekylespecifikke optiske sensorer til on-site, ikke-destruktiv måling. Afhandlingen falder i tre dele, to teoriafsnit, hvor første...... del omhandler den tilgangelige molekylære information ved overfladeforstærket resonans Raman spredning (SERRS), samt hvordan adgangen til denne information kan optimeres. Anden del omhandler, hvordan det molekylære informationsindhold kan forøges ved at kombinere polariserede Raman og resonans Raman...... målinger på frie molekyler med multivariat analyse. I tredje og sidste del, som er et eksperimentelt afsnit, præsenteres og diskuteres overfladeforstærkede Raman målinger (SERS) på tre udvalgte pesticider. Afhandlingen indledes med en diskussion af teorien bag SERRS med speciel fokus på den molekylære...

  10. Internal resonances in periodically modulated long Josephson junctions

    DEFF Research Database (Denmark)

    Larsen, Britt Hvolbæk; Mygind, Jesper; Ustinov, Alexey V.

    1995-01-01

    Current-voltage (I-V) characteristics of long Josephson junctions with a periodic lattice of localized inhomogeneities are studied. The interaction between the moving fluxons and the inhomogeneities causes resonant steps in the IV-curve. Some of these steps are due to a synchronization to resonan...... into account the interaction between the resonance in the sub-junction and the magnetic flux density waves excited in the whole junction is given....... Fiske modes in the sub-junctions formed between the inhomogeneities. The voltage positions of the resonant steps oscillate as function of the applied magnetic field with a period corresponding to the inclusion of one magnetic flux quantum, Φ0=h/2e, per sub-junction. A qualitative explanation that takes...

  11. Transient Regional Osteoporosis of the Hip: Case Report - Case Report

    Directory of Open Access Journals (Sweden)

    İlknur Aktaş

    2006-12-01

    Full Text Available Transient regional osteoporosis of the hip (TOH is an uncommon cause of hip pain. It affects mostly healthy middle-aged men, and women in the third trimester of pregnancy. The aetiology is unknown. Differential diagnosis includes avascular necrosis, stress fracture, septic arthritis, malignancy, soft-tissue injury, osteoarthrosis and radiculopathy. Due to its association with bone marrow oedema, TOH is a pathology in which magnetic resonans imaging is extremely important in differential diagnosis. In this paper, a male patient with complaint of hip pain and difficulty in walking, which was diagnosed as TOH was presented by reviewing current literature. (Osteoporoz Dünyasından 2006;12:87-90

  12. Cervical brucellar spondylodiscitis mimicking a cervical disc herniation with epidural abscess: a case report

    Directory of Open Access Journals (Sweden)

    Ahmet Aslan

    2014-05-01

    Full Text Available Brucellosis can show many clinical manifestations according to the affected sites of the body, and is usually diagnosed with osteoarticular symptoms. We present a patient with cervical brucellar spondylodiscitis and epidural abscess who presented with severe neck and left upper extremity pain and was referred to our hospital for surgery because of cervical disc herniation. The patient didn’t undergo surgery and was cured with 6 months of medical therapy. Duration of the medical therapy was assessed by magnetic resonans imaging (MRI studies. In endemic regions, brucellar spondylodiscitis should be included in differential diagnoses for patients who have cervical pain with or without neurological deficits. Patients should be attentively questioned concerning occupation, settlement place, subfebril fever, consumption of raw milk or dairy products, travel to endemic regions or past brucellosis history in the family. MRI is an important imaging modality in the diagnosis and response to medical treatment in brucellar spondylodiscitis.

  13. Observation of snake resonances at Relativistic Heavy Ion Collider

    Science.gov (United States)

    Bai, M.; Ahrens, L.; Alekseev, I. G.; Alessi, J.; Courant, E.; Drees, A.; Fischer, W.; Gardner, C.; Gill, R.; Glenn, J.; Huang, H.; Litvinenko, V.; Luccio, A.; Luo, Y.; Pilat, F.; MacKay, W. W.; Makdisi, Y.; Marusic, A.; Minty, M.; Montag, C.; Ptitsyn, V.; Roser, T.; Svirida, D.; Satogata, T.; Tepikian, S.; Trbojevic, D.; Tsoupas, N.; Zelenski, A.; Zeno, K.; Zhang, S. Y.

    2011-05-01

    The Siberian snakes are powerful tools in preserving polarization in high energy accelerators has been demonstrated at the Brookhaven Relativistic Heavy Ion Collider (RHIC). Equipped with two full Siberian snakes in each ring, polarization is preserved during acceleration from injection to 100 GeV. However, the Siberian snakes also introduce a new set of depolarization resonances, i.e. snake resonances as first discoverd by Lee and Tepikian [1]. The intrinsic spin resonances above 100 GeV are about a factor of two stronger than those below 100 GeV which raises the challenge to preserve the polarization up to 250 GeV. In 2009, polarized protons collided for the first time at the RHIC design store energy of 250 GeV. This paper presents the experimental measurements of snake resonances at RHIC. The plan for avoiding these resonanances is also presented.

  14. [Vitex Agnus Castus in the treatment of hyperprolactinemia and menstrual disorders - a case report].

    Science.gov (United States)

    Męczekalski, Błażej; Czyżyk, Adam

    2015-07-01

    We describe a patient with mild hyperprolactinemia and menstrual disorders (oligomenorrhea). She presented relative hypoestrogenism in laboratory tests. Magnetic resonans excluded the presence of pituitary adenoma. Because patient developed a bromocriptine intolerance, the Vitex Agnus Castus (VAC) extract has been introduced. The VAC therapy was effective, with symptoms relief and improvement of hormonal tests. The VAC medicines are indicated for the treatment of premenstrual syndrome (PMS), mastalgia, menstrual disorders and mild hyperprolactinemia. The mechanism of action is not fully understood, but it is related to dopaniergic activity of diterpenes and castacin in VAC. The randomized clinical trials revealed efficacy of VAC extract in the treatmet of hyperprolactinemia, menstrual disorders, PMS and mastalgia. Good tolerability, lack of serious side-effects and drug interactions are the advantages of the VAC preparations.

  15. Offshore 2010. Final report; Offshore 2010. Sluttrapport

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    An overview of the accomplishments of the various projects that have received support from the Norwegian Research Council's program 'Offshore 2010'. The following projects are presented, some have English and some Norwegian project names: 'Critical parameters influencing inhibitor performance in multiphase flow', 'Development of the drilling optimization simulator (DDS) and a totally integrated drilling optimization system', 'Produksjonsoptimalisering og automatisk styring av broenner og roerledninger (PETRONICS)', 'Termisk isolerte undervannsroer for sikring av broenntransport over store avstander', 'Utvikling av magnetisk frekvensformer for styring av store subsea pumper paa havdyp ned mot 4000 meter', 'Flerfase stroemningsmaaler for permanent nedihulls installasjon', 'Hastighetsmaaling i flerfase stroemning ved passiv akustikk', 'Oil/water seperation offshore: optimized flow- and seperation behavior', 'Stroemningshastighet', 'A rock mechanics based reservoir simulation', 'MultiTool fase 2 - et flerbruksverktoey for nedihulls applikasjoner', 'Utvikling av undervanns olje-i-vann monitor for kontinuerlig maaling av lave oljekonsentrasjoner basert paa TR-LIFS', 'Subsea multipath ultrasonic liquid flow meter', 'Fluid characterization at elevated pressures and temperatures (Flucha II)'. The two main goals for the research program are 1. The development of new technology and competency in the field of downhole- and subsea processing and multiphase transportation, and 2. Innovation and commercialisation in small and medium sized companies (less than 100 employees). Some details on the financing and results are included (ml)

  16. LHC vector resonance searches in the $t\\bar{t} Z$ final state

    CERN Document Server

    Backović, Mihailo; Jain, Bithika; Lee, Seung J

    2016-01-01

    LHC searches for BSM resonances in $l^+ l^-, \\, jj, \\, t\\bar{t}, \\gamma \\gamma$ and $VV$ final states have so far not resulted in discovery of new physics. Current results set lower limits on mass scales of new physics resonances well into the $\\mathcal{O}(1)$ TeV range, assuming that the new resonance decays dominantly to a pair of Standard Model particles. While the SM pair searches are a vital probe of possible new physics, it is important to re-examine the scope of new physics scenarios probed with such final states. Scenarios where new resonances decay dominantly to final states other than SM pairs, even though well theoretically motivated, lie beyond the scope of SM pair searches. In this paper we argue that LHC searches for (vector) resonances beyond two particle final states would be useful complementary probes of new physics scenarios. As an example, we consider a class of composite Higgs models, and identify specific model parameter points where the color singlet, electrically neutral vector resonan...

  17. Influence of information flow in the formation of economic cycles

    CERN Document Server

    Miskiewicz, J; Miskiewicz, Janusz; Ausloos, Marcel

    2005-01-01

    A microscopic approach to macroeconomic features is intended. A model for macroeconomic behavior based on the Ausloos-Clippe-Pekalski model is built and investigated. The influence of a discrete time information transfer is investigated. The formation of economic cycles is observed as a function of the time of information delay. Three regions of delay time are recognized: short $t_d \\in (2 IS, 4 IS)$ (IS - iteration steps) - the system evolves toward a unique stable equilibrium state, medium $t_d =5 IS $ or $t_d =6 IS $, the system undergoes oscillations: stable concentration cycles appear in the system. For long information flow delay times, $t_d \\geq 7$, the systems may crash for most initial concentrations. However, even in the case of long delay time the crash time may be long enough to allow observation of the system evolution and to introduce an appropriate strategy in order to avoid the collapse of the e.g. company concentration. In the long time delay it is also possible to observe an "economy resonan...

  18. The $Z \\to \\mu^{+}\\mu^{-}$ decay channel in the CMS experiment at LHC: from cross-section measurement with the 2010 7 TeV collision dataset to offline machine luminosity monitor

    CERN Document Server

    De Gruttola, Michele; Sciacca, Crisostomo

    2010-01-01

    This thesis has been possible thank to a bourse from Italian Minister of Education, MIUR. During the phd program I had the opportunity to take part actively to the CMS experiments at CERN: many aspects of the chain to take and analyze the data have been studied. Indeed, in the first year of the phd program a tool to store and retrieve the CMS condition data in the CMS databases has been developed. A web monitor tool has been also deployed to trace and check the correctness of the transactions. Instead, in the second and third year of the phd program the decay of the Z boson in two muons has been analyzed. The CMS detector, which took 7 TeV collision data for the entire 2010 at CERN, is designed to provide precise measurements of TeV proton-proton collisions at the Large Hadron Collider. The measurements of the cross section of the Z boson production at LHC provides a first test of the Standard Model in a new energy domain and may reveal exotic physics processes. Moreover, the properties of the Z boson resonan...

  19. Interkulturelt ungdomsarbeid i spennet mellom gamle og nye forestillinger

    Directory of Open Access Journals (Sweden)

    Kristin Beate Vasbø

    2014-11-01

    Full Text Available Artikkelen beskriver betydningen av forestillinger om kulturelle fellesskap og kulturelle forskjeller når unge møtes på internasjonale ungdomsutvekslinger, og hva det innebærer for det interkulturelle læringsutbyttet når tematisering av nettopp disse forestillingene er så godt som fraværende innenfor de pedagogiske rammene. Analysen er basert på en etnografisk studie av en norsk ungdomsgruppe før, under og etter en internasjonal ungdomsutveksling i Brasil. Studiens funn viser at ungdommen selv fremsto som både representanter og produsenter av en transkulturell kulturforståelse, mens de voksenstyrte pedagogiske rammene var forankret i et utdatert og tradisjonelt kulturbegrep. Disse kulturperspektivene representerer motstridende fortolkninger av hva som konstituerer forskjell og likhet. Analysen viser at manglende tematisering av forskjeller medførte enten at ungdommene skapte stereotypier av seg selv og «de andre», eller at reelle og erfarte ulikheter mellom ungdomsgruppene ble utvisket av deres opplevelse av å dele en lang rekke globale ungdomskulturelle uttrykk. For å nå målsettingen om å styrke de unges interkulturelle læringsutbytte må interkulturelt ungdomsarbeid ta utgangspunkt i en transkulturell kulturforståelse som gir resonans i de unges hverdagserfaringer.

  20. Plutino 15810 (1994 JR1), an accidental quasi-satellite of Pluto

    CERN Document Server

    Marcos, C de la Fuente

    2012-01-01

    In the solar system, quasi-satellites move in a 1:1 mean motion resonance going around their host body like a retrograde satellite but their mutual separation is well beyond the Hill radius and the trajectory is not closed as they orbit the Sun not the host body. So far, minor bodies temporarily trapped in the quasi-satellite dynamical state have been identified around Venus, Earth, the dwarf planet (1) Ceres, the large asteroid (4) Vesta, Jupiter, Saturn and Neptune. Using computer simulations, Tiscareno and Malhotra have predicted the existence of a small but significant population of minor bodies moving in a 1:1 mean motion resonance with Pluto. Here we show using N-body calculations that the Plutino 15810 (1994 JR1) is currently an accidental quasi-satellite of Pluto and it will remain as such for nearly 350,000 yr. By accidental we mean that the quasi-satellite phase is triggered (or terminated) not by a direct gravitational influence in the form of a discrete close encounter but as a result of a resonan...

  1. Dipole response in 208Pb within a self-consistent multiphonon approach

    CERN Document Server

    Knapp, F; Vesely, P; Andreozzi, F; De Gregorio, G; Porrino, A

    2015-01-01

    Background: The electric dipole strength detected around the particle threshold and commonly associated to the pygmy dipole resonance offers a unique information on neutron skin and symmetry energy, and is of astrophysical interest. The nature of such a resonance is still under debate. Purpose: We intend to describe the giant and pygmy resonances in 208 Pb by enhancing their fragmentation with respect to the random-phase approximation. Method: We adopt the equation of motion phonon method to perform a fully self-consistent calculation in a space spanned by one-phonon and two-phonon basis states using an optimized chiral two-body potential. A phenomenological density dependent term, derived from a contact three-body force, is added in order to get single-particle spectra more realistic than the ones obtained by using the chiral potential only. The calculation takes into full account the Pauli principle and is free of spurious center of mass admixtures. Results: We obtain a fair description of the giant resonan...

  2. Segmentation and Labelling of Human Spine MR Images Using Fuzzy Clustering

    Directory of Open Access Journals (Sweden)

    Jiyo.S.Athertya

    2016-04-01

    Full Text Available Computerized medical image segmentation is a challe nging area because of poor resolution and weak contrast. The predominantly used conventio nal clustering techniques and the thresholding methods suffer from limitations owing to their heavy dependence on user interactions. Uncertainties prevalent in an image c annot be captured by these techniques. The performance further deteriorates when the images ar e corrupted by noise, outliers and other artifacts. The objective of this paper is to develo p an effective robust fuzzy C- means clustering for segmenting vertebral body from magnetic resonan ce images. The motivation for this work is that spine appearance, shape and geometry measureme nts are necessary for abnormality detection and thus proper localisation and labellin g will enhance the diagnostic output of a physician. The method is compared with Otsu thresho lding and K-means clustering to illustrate the robustness. The reference standard for validation was the annot ated images from the radiologist, and the Dice coefficient and Hausdorff distance measures were used to evaluate the segmentation.

  3. Study of the Xi(1620) and Xi(1690) resonances in Xi_c -> pi^+ MB decays

    CERN Document Server

    Miyahara, Kenta; Oka, Makoto; Nieves, Juan; Oset, Eulogio

    2016-01-01

    Nonleptonic weak decays of Xi_c into pi^+ and a meson (M)-baryon (B) final state, MB, are analyzed from the viewpoint of probing S=-2 baryon resonances, i.e. Xi(1620) and Xi(1690), which spin-parity and other properties are not well known. We argue that the weak decay of Xi_c is dominated by a single quark-line diagram, preferred by the Cabibbo-Kobayashi-Maskawa coefficient, color recombination factor, the diquark correlation, and the kinematical condition. The decay process has an advantage of being free from meson resonances in the pi^+M invariant mass distribution. The invariant mass distribution of the meson-baryon final state is calculated with three different chiral unitary approaches, assuming that the Xi(1620) and Xi(1690) resonances have J^P=1/2^-. It is found that a clear peak for the Xi(1690) is seen in the piXi and KbarLambda spectra. We also suggest that the ratios of the piXi, KbarLambda and KbarSigma final states are useful to distinguish whether the peak is originated from the Xi(1690) resonan...

  4. El lenguaje de las cosas desconocidas: tríptico de la cuestión

    Directory of Open Access Journals (Sweden)

    Juan Sebastián Ballén Rodríguez

    2015-01-01

    Full Text Available En la historia de la antropología filosófica ninguna otra cuestión ha dimensionado el carácter problemático y paradójico que se desprende de la cuestión acerca de lo que significa ser hombre. Las líneas de fuga que aquí se proponen, son lecturas comple - mentarias a las formuladas por la tradición metafísica (Aristó - teles, Santo Tomás y Heidegger, estructuralista (Levi-Strauss y Foucault y cultural (Protágoras de Abdera y Nietzsche. Se ins - cribe en la tradición de la filosofía trascendental, pero acentuan - do el énfasis en una obra poco explorada desde una mirada an - tropológica, y la cual parte originariamente de una preocupación estética. La tercera crítica kantiana es el “caldo de cultivo” sobre el cual se proyectarán las bases de un apuesta teórica que he denominado antropología simbólica , propuesta cuya caja de resonan - cia evocará la tradición de la Antropología filosófica. Introducción a una Filosofía de la cultura (1944 del neokantiano Ernst Cassirer, y desde Latinoamérica, en una perspectiva actual, con las investigaciones adelantadas por el filósofo mexicano Mauricio Beuchot, particularmente su provocadora propuesta de una hermenéutica analógica, y que en este primer estudio será valorada a partir de un libro diciente y profundo titulado Hermenéutica, analogía y símbolo (2004.

  5. A practical MRI technique for detecting Abdominal Aorta Aneurism and Peripheral Arterial Disease

    Directory of Open Access Journals (Sweden)

    Aykut Aktas

    2014-12-01

    Full Text Available Aim: Peripheral Arterial Disease(PAD and abdominal aorta aneurysm(AAA are frequent problems in geriatric population. In DSA, CTA or MRA techniques contrast agents has to be used for diagnosis that can be nephrotoxic for elderly patients. Magnetic resonans imaging (MRI is the most powerful, non-ionising radiological diagnostic tool that has the highest soft tissue contrast resolution. The aim of our study was to investigate the effectivity of MRI by the means of detecting the AAA and PAD in comparison with DSA. Material and Method: After getting ethical commitee approvel and informed consent, we have performed Balanced turbo field echo(B-TFE MRI technique without contrast agent in 1.5 Tesla MRI device before DSA examination. The luminal diameters of renal arteries, infrarenal abdominal aorta, iliac and femoral arteries was measured by using Philips DICOM Viewer R2.2 application. The intraclass corelation coefficient and reliability used to check if the techniques could be used for each other and the t-test was used to measure the differences between them. Results: There has been a high relationship between B-TFE and DSA in detecting the pathologies of larger arteries like aorta. In the case of small arterial pathologies, there is relatively lower relationship between BTFE and DSA. Discussion: For the diagnosis of AAA and PAD, DSA is the gold standart technique but it is invasive and patients have radiation exposure. In the follow up of geriatric patients with larger arterial pathologies B-TFE can be used instead of contrast enhanced MRA and invasive DSA.

  6. 改进的基于安全距离的车辆跟驰模型%Improved Safe Distance Car-following Model

    Institute of Scientific and Technical Information of China (English)

    杨达; 蒲云; 祝俪菱; 杨飞; Ran Bin

    2013-01-01

    Gipps' model,the well-known safe distance car-following model,has a strict restriction on the car-following behavior,that is,the following vehicle has to maintain the exact safe distance with the leading vehicle to avoid accident.However,this restriction is not consistent with the reality.Owning to this reson,an enhanced safe distance car-following model was proposed first,and then evaluated by comparing with Gipps' model.Furthermore,simulations were conducted to analyze the characteristics of the new model.The results of evaluation and simulation illustrate that the proposed model has more accurate prediction result than Gipps' model,and can reproduce the stable flow and shockwave that are very common in real traffic flow.In addition,the enhanced model can stabilize traffic flow.%由于经典的基于安全距离的车辆跟驰模型Gipps模型要求车辆行驶时恰好与前车保持安全距离,这是一个对车辆跟驰行为过分严格的约束,不符合实际情况,根据实际情况提出车辆跟驰距离是有关安全距离和前后车相对速度的函数,并据此建立了改进的基于安全距离的车辆跟驰模型.NGSIM数据经过处理后被用来标定Gipps 模型和改进后的模型,在标定结果的基础上对模型进行了统计意义上和仿真预测能力上的模型评价.结果显示:改进后的基于安全距离的车辆跟驰模型比Gipps模型有更高的仿真精确,可以再现出宏观交通中的稳定交通流和冲击波等常见的交通现象,并且改进模型在一定程度上使交通流变得更加稳定.

  7. COMPUTATIONAL INVESTIGATION ON CSF FLOW ANALYSIS IN THE THIRD VENTRICLE AND AQUEDUCT OF SYLVIUS

    Directory of Open Access Journals (Sweden)

    Edi Azali Hadzri

    2011-12-01

    Full Text Available In this study, a three dimensional (3D model of the third ventricle and aqueduct of Sylvius derived from MRI scans was constructed by using Computational Fluid Dynamics (CFD modeling. Cerebrospinal fluid(CSF can be modeled as a Newtonian Fluid and its flow through the region of interest (ROI was visualized using Engineering Fluid Dynamics (EFD.The constructed ROI was regarded as rigid walled and only steady state flow was able to be defined due to the limitations of current software. Different flow rate was simulated at the Foramen of Monro and a small stenosis was modeled at the middle of the aqueduct of Sylvius at a fixed location. This was made corresponding to normal patients with variation of CSF flow rate physiologically and abnormal patients with tumor causing obstruction to or within the aqueduct of Sylvius, respectively. Due to the small dimensions of the ROI geometry, gravity and complex external gravity that acted upon it was considered to be neglected. The results show as the flow rate increase, the pressure drop of CSF in the ROI proportionally increased. For normal CSF flow rate, the presence of stenosis in the aqueduct demonstrates a significant increased pressure drop.ABSTRAK-Dalam kajian ini, model tiga dimensi (3D untuk ventrikel ketiga dan akueduk Sylvius, yang terhasil daripada pengimejan resonans magnetik telah dikonstruksi menggunakan Permodelan Perkomputeran Dinamik Bendalir (Computational Fluid Dynamics (CFD. Cecair serebrospinal (Cerebrospinal fluid (CSF dimodelkan sebagai bendalir Newtonan dan alirannya melalui kawasan kepentingan (region of interest (ROI digambarkan menggunakan Dinamik Bendalir Kejuruteraan (Engineering Fluid Dynamics (EFD. Kawasan kepentingan yang dikonstruksi dianggap sebagai dinding tegar dan hanya aliran keadaan tunak yang dapat ditakrifkan berdasarkan pengehadan perisian komputer terkini. Kadar aliran yang berbeza disimulasikan di foramen monro dan laluan stenosis yang kecil dimodelkan di tengah

  8. Yağ dokusu İçeren Nadir Bir Stafne Kemik Kavitesi Olgusu

    Directory of Open Access Journals (Sweden)

    Erman Şenel

    2012-07-01

    Full Text Available

    Stafne bone cavities are firstly reported by Stafne in the angle of mandibles in1942. These cavities are usually located at the lingual side in the area between the mandibular first molar and the mandibular angle, and are not considered rare. They are usually unilateral and casually diagnosed during routine radiographic examination. One of their primary radiological diagnostic features is the characteristic location below the mandibular canal. Because of the diagnostic mixtures between the Stafne bone cavities and other radiolucent lesions, detailed visualization procedures are essential. The Dental Computerized Tomography (DCT scan is suggested as the most suitable noninvasive diagnostic and follow-up modality for this bony configuration in the posterior mandible. Magnetic Resonans Imagenes (MRI findings give detailed information to the surgeons about the content of the these cavities.  In this paper, we present a rare case of Stafne Bone Cavity which has fatty content. Its differential diagnosis was carried out with DCT and MRI.

    Keywords: Stafne bone cavity, adipose tissue, dental computerized tomography, MRI.

     

    ÖZET

    Stafne kemik kavitesi, 1942 yılında ilk defa Stafne tarafından mandibula angulusunda rapor edilmiştir. Bu kaviteler genellikle mandibula angulusu ve mandibuler birinci molar arasında lingualde lokalizedirler ve nadir oldukları düşünülmez. Genelikle tek taraflı ve rutin radyografik muayene sırasında tesadüfen teşhis edilirler. Radyolojik teşhiste primer özelliklerinden biri de mandibuler kanalın altında karakteristik lokasyonlarıdır. Stafne Kemik Kavitesi ve diğer lezyonların teşhis açısından neden olacağı karışıklardan dolayı detaylı görüntülemeler çok önemlidir. Dental Bilgisayarlı Tomografi (DBT mandibula posteriorundaki bu kemik konfigürasyonlarının teşhis ve takibinde en uygun noninvaziv metod olarak

  9. SILICON COMPATIBLE ACOUSTIC WAVE RESONATORS: DESIGN, FABRICATION AND PERFORMANCE

    Directory of Open Access Journals (Sweden)

    Aliza Aini Md Ralib

    2014-12-01

    -unsur diskret kerana keupayaan untuk mengintegrasikan dengan litar yang disertakan itu. Integrasi ini membawa kepada peningkatan prestasi, fungsi yang lebih baik dengan pengurangan kos pada pengeluaran jumlah yang besar. Oleh itu, Karya ini mengkaji silikon resonator akustik yang serasi, yang bersepadu dengan muka litar untuk membolehkan integrasi yang lengkap. Resonator gelombang akustik yang digunakan adalah gelombang permukaan akustik ( SAW dan gelombang akustik pukal ( BAW resonator . Kriteria penting untuk menilai prestasi resonator seperti faktor kualiti, frekuensi resonans dan kehilangan sisipan juga digariskan dalam setiap kerja sebelumnya. Pemilihan bahan piezoelektrik yang sesuai adalah penting untuk memastikan pekali gandingan elektromekanik yang mencukupi dihasilkan untuk mengurangkan kehilangan sisipan. Lapisan tambahan pasif SiO2   yang bertindak sebagai bahan rendah sisipan dipercayai meningkatkan faktor kualiti dan kestabilan suhu reka bentuk. Teknik integrasi juga dipengaruhi oleh proses fabrikasi dan pembungkusan. Struktur tanpa pembungkusan menggunakan AlN sebagai lapisan pengasingan tambahan itu dicadangkan untuk melindungi peranti SAW dari persekitaran untuk kebolehpercayaan yang tinggi. Banyak lagi kemajuan perlu dilakukan dalam pengecilan silikon serasi resonator gelombang akustik untuk merealisasikan sistem cip transceiver tunggal.KEYWORDS: RF-MEMS; piezoelectric; resonator; surface acoustic wave (SAW;bulk acoustic wave (BAW; FBAR

  10. SOUND TRANSMISSION LOSS OF A DOUBLE-LEAF SOLID-MICROPERFORATED PARTITION UNDER NORMAL INCIDENCE OF ACOUSTIC LOADING

    Directory of Open Access Journals (Sweden)

    Ahmad Yusuf Ismail

    2011-12-01

    (sound transmission loss (TL oleh satu panel padu yang digandingkan dengan satu panel bertebuk mikro. Kaedah ini menghasilkan satu sekatan lembar kembar yang sememangnya dikenali sebagai struktur ringan penebat bunyi di dalam kenderaan dan bangunan. Model matematik diterbitkan untuk TL tersebut dengan menjalankan pengujaan akustik yang tuju normal. Keputusan menunjukkan bahawa prestasi meningkat dengan ketara pada frekuensi yang susah semasa resonans jisim-udara-jisim berlaku di dalam sekatan padu lembar kembar  lazim. Ini penting terutamanya untuk sumber bunyi yang pradominan pada frekuensi rendah. Ia juga boleh dikawal dengan menalakan saiz dan jumlah lubang serta luang udara di antara panel-panel  tersebut.