922 resultados para Radio coverage
Resumo:
Cognitive radio networks sense spectrum occupancyand manage themselves to operate in unused bands without disturbing licensed users. Spectrum sensing is more accurate if jointly performed by several reliable nodes. Even though cooperative sensing is an active area of research, the secureauthentication of local sensing reports remains unsolved, thus empowering false results. This paper presents a distributed protocol based on digital signatures and hash functions, and ananalysis of its security features. The system allows determining a final sensing decision from multiple sources in a quick and secure way.
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The impact of curative radiotherapy depends mainly on the total dose delivered homogenously in the targeted volume. Nevertheless, the dose delivery is limited by the tolerated dose of the surrounding healthy tissues. Two different side effects (acute and late) can occur during and after radiotherapy. Of particular interest are the radiation-induced sequelae due to their irreversibility and the potential impact on daily quality of life. In a population treated in one center with the same technique, it appears that individual radiosensitivity clearly exists. In the hypothesis that genetic is involved in this area of research, lymphocytes seem to be the tissue of choice due to easy accessibility. Recently, low percentage of CD4 and CD8 lymphocyte apoptosis were shown to be correlated with high grade of sequelae. In addition, recent data suggest that patients with severe radiation-induced late side effects possess four or more SNP in candidate genes (ATM, SOD2, TGFB1, XRCC1 et XRCC3) and low radiation-induced CD8 lymphocyte apoptosis in vitro.
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The objective of this master's thesis is to evaluate the optimum performance of sixsectored hexagonal layout of WCDMA (UMTS) network and analyze the performance at the optimum point. The maximum coverage and the maximum capacity are the main concern of service providers and it is always a challenging task for them to achieve economically. Because the optimum configuration of a network corresponds to a configuration which minimizes the number of sites required to provide a target service probability in the planning area which in turn reduces the deployment cost. The optimum performance means the maximum cell area and themaximum cell capacity the network can provide at the maximum antenna height satisfying the target service probability. Hexagon layout has been proven as the best layout for the cell deployment. In this thesis work, two different configurations using six-sectored sites have been considered for the performance comparison. In first configuration, each antenna is directed towards each corner of hexagon, whereas in second configurationeach antenna is directed towards each side of hexagon. The net difference in the configurations is the 30 degree rotation of antenna direction. The only indoor users in a flat and smooth semi-urban environment area have been considered for the simulation purpose where the traffic distribution is 100 Erl/km2 with 12.2 kbps speech service having maximum mobile speed of 3 km/hr. The simulation results indicate that a similar performance can be achieved in both the configurations, that is, a maximum of 947 m cellrange at antenna height of 49.5 m can be achieved when the antennas are directed towards the corner of hexagon, whereas 943.3 m cell range atantenna height of 54 m can be achieved when the antennas are directed towards the side of hexagon. However, from the interference point of view the first configuration provides better results. The simulation results also show that the network is coverage limited in both the uplink and downlink direction at the optimum point.
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The mass media are assigned an important role in political campaigns on popular votes. This article asks how the press communicates political issues to citizens during referendum campaigns, and whether some minimal criteria for successful public deliberation are met. The press coverage of all 24 ballot votes on welfare state issues from 1995 to 2004 in Switzerland is examined, distinguishing seven criteria to judge how news coverage compares to idealized notions of the media's role in the democratic process: coverage intensity, time for public deliberation, balance in media coverage, source independence and inclusiveness, substantive coverage, and spatial homogeneity. The results of our quantitative analysis suggest that the press does fulfil these normative requirements to a reasonable extent and that fears about biased or deceitful media treatment of ballot issues are not well-founded. However, some potential for optimizing the coverage of referendum campaigns by the Swiss press does exist
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OBJECTIVE: To investigate the determinants and the 4-year evolution of the forgoing of healthcare for economic reasons in Switzerland. METHOD: Population-based survey (2007-2010) of a representative sample aged 35-74years in the Canton of Geneva, Switzerland. Healthcare forgone, socioeconomic and insurance status, marital status, and presence of dependent children were assessed using standardized methods. RESULTS: A total of 2601 subjects were included in the analyses. Of the subjects, 13.8% (358/2601) reported having forgone healthcare for economic reasons, with the percentage varying from 3.7% in the group with a monthly income ≥13,000CHF (1CHF≈1$) to 30.9% in the group with a monthly income <3000CHF. In subjects with a monthly income <3000CHF, the percentage who had forgone healthcare increased from 22.5% in 2007/8 to 34.7% in 2010 (P trend=0.2). Forgoing healthcare for economic reasons was associated with lower income, female gender, smoking status, lower job position, having dependent children, being divorced and single, paying a higher deductible, and receiving a premium subsidy. CONCLUSION: In a Swiss region with universal health insurance coverage, the reported prevalence of forgoing healthcare for economic reasons was high and greatly dependent on socioeconomic factors. Our data suggested an increasing trend among participants with the lowest income.
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Kiristyville markkinoille on aina tuotava jotain uutta tarjottavaa ja SDH-kortti on yksi sellainen tuote jonka Nokia Networks julkistaa osaksi uutta Nokia Flexihub Nodea. Tavoitteena on suunnitella VC-12kanavoitu STM-1 kortti yhdistämään ylemmän tason tietoliikenneverkko suuren kapasiteetin radioon. Ennen kuin markkinoilla on valmis tuote, on sen takana valtaisa määrä työtä. Erilaisia dokumentteja on pitänyt tuottaa ja sopimuksia tehdä. Esimerkiksi vaatimusmäärittelyt on oltava selvät, jotta tiedetään mitä tuotteelta halutaan. Tätä ennen on kuitenkin pitänyt ymmärtää miten SDHtoimii ja miten otsikkotavuja käsitellään. Myös erilaiset piirivalinnat aiheuttavat miettimistä, sillä markkinoilla on runsaasti valmiita piirejä SDH signaalinkäsittelyyn. Varma tiedonsiirto on tärkeää puhelinoperaattorille ja siksi joudutaan miettimään varmennuksia ja niiden toteuttamista. Myös synkronointi on tärkeä osa SDH järjestelmää ja sen toteuttaminen hyvin on tärkeää. Hälytykset on otettava huomioon ja mietittävä, miten niiden käsittely saadaan hoidettua järkevästi, ilman että mikään järjestelmän osa ruuhkautuu kohtuuttomasti. Tässä Diplomityössä on tutustuttu SDH-järjestelmään, otsikkotavujen käsittelyyn ja vaatimusmäärittelyihin.
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Burn care and research have significantly improved over the past years. However, insurance coverage of such treatments does not reflect the improvements in this multi-disciplinary field. Government insurance policies in first world countries renown for burn care treatment, such as Switzerland and the United States, have not adapted to the complexity and longitudinal nature of burn care. Using case studies from both countries, we have analyzed both the institutional and policy approach to pediatric burn treatment coverage. Subsequently, by presenting the Shriners burn care model, we offer a policy recommendation to both the Swiss and the American governments to better their present legislation and infrastructure on pediatric burn coverage.
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Marked differences in the tumor uptake of a 125I-labeled monoclonal antibody (MAb) directed against carcinoembryonic antigen (CEA) were observed in 4 serially transplanted human colorectal carcinomas in nude mice. A comparative study showed that elevated values of measurable tumor vascular parameters, such as permeability, blood flow and blood volume, correlated better with high MAb tumor uptake than the concentration of target antigen in the tumor. In an attempt to modify the vascular parameters and to determine if this could increase antibody uptake by the tumor, rhTNF alpha (TNF) was injected i.t. or i.v. and antibody localization experiments were performed immediately thereafter. Results showed that the permeability of the tumor vessels increased 8 to 10 fold 1 hr after i.t. injection of TNF as compared to control tumors injected with saline. Tumor uptake of 125I-labeled anti-CEA MAb, was 3 times higher 2 hr after i.v. injection and still 27% higher 22 hr later, as compared to results from controls. Intravenous injection of TNF simultaneously with the 125I-labeled anti-CEA MAb also resulted in a 2-fold increase in tumor uptake 4 hr after injection, but the increase was no longer significant 24 hr after injection. Interestingly after i.v. injection of TNF, the MAb concentration in the blood and other normal tissues, such as liver, kidneys, lungs and heart was decreased, resulting in significantly higher ratios of tumor to normal tissue. Taken together the results demonstrate that injection of TNF can increase tumor vascular permeability and improve radio-antibody uptake. This raises the possibility of increasing the radiation dose delivered by antibody to the tumor in the course of radioimmunotherapy.
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Résumé: La qualité de l'implantation d'une prothèse totale du genou est un facteur essentiel déterminant le résultat clinique à long terme. L'alignement postopératoire des membres inférieurs est considéré comme le facteur influençant le plus la survie à long terme d'une arthroplastie du genou. Au vu du haut degré de corrélation entre les complications post-opératoires et les malpositionnements prothétiques, les chirurgiens ont tenté de développer durant ces deux dernières décennies des instruments chirurgicaux améliorant la précision d'implantation. Depuis le début des années 90, de nouvelles instrumentations assistées par ordinateur ont été proposées. Actuellement, en chirurgie prothétique du genou, la plus utilisée de ces techniques est le système de navigation OrthoPilot® qui permet, grâce à une station de navigation et des émetteurs infrarouges, de contrôler en continu pendant l'opération, l'axe mécanique du membre inférieur et de vérifier la précision des coupes osseuses. Le but de cette étude de cohorte appareillée rétrospective est de comparer les résultats clinique et radiologiques de deux collectifs de patients (32 patients dans chaque groupe) comparables (âge, sexe, BMI, degré d'arthrose, recul postopératoire), opérés avec le même type de prothèse (prothèse à glissement tricompartimental postérieurement stabilisée), soit avec le système de navigation Orthopilot®, soit à l'aide de l'instrumentation ancillaire mécanique classique. Les résultats obtenus montrent que la technique chirurgicale supportée par le système de navigation Orthopilot® est fiable et aisément reproductible. Par rapport à l'instrumentation manuelle, l'instrumentation assistée améliore significativement la précision de pose du composant tibial dans le plan frontal. Cependant entre des mains expérimentées, la technique d'alignement mécanique classique, plus simple, reste performante (coût modique, temps opératoire plus court et sans risque de défaillance technique).
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Tämä diplomityö tarkastelee TETRA-verkon soveltuvuutta turvallisuusviranomaisille tarkoitettuun telemetriasovellukseen, jossa erilaiset mittausdatat ja hälytystiedot kulkevat verkon yli SDS-viestiliikenteenä. Diplomityön tarkoituksena on tehdä kaksi sulautettua ohjelmistoa sekä yksi PCohjelmisto, joita käytetään rakennettavassa demolaitteistossa. Lisäksi selvitetään TETRA-verkon toimivuus ja rajoitukset sovelluksessa eri olosuhteissa ja eri kuormitustilanteissa. Diplomityön teoriaosassa käydään läpi työn määrittely ja ohjelmistonkehitysprosessin läpivienti eri osa-alueilla. Loppuosassa kuvataan tehdyt ohjelmistot erikseen ja yhdessä suunnittelusta toteutukseen, sekä lopullisen järjestelmän testaus.
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Data from studies in the United States suggest that young people engaging in health-compromising behaviors have lower access to health care. Using data from a Swiss national survey we tested the hypothesis that in a country with universal insurance coverage, adolescents engaging in health-compromising behaviors access primary care to the same extent as those who do not engage in these behaviors.
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Personal results are presented to illustrate the development of immunoscintigraphy for the detection of cancer over the last 12 years, from the early experimental results in nude mice grafted with human colon carcinoma to the most modern form of immunoscintigraphy applied to patients, using I123 labeled Fab fragments from monoclonal anti-CEA antibodies detected by single photon emission computerized tomography (SPECT). The first generation of immunoscintigraphy used I131 labeled, immunoadsorbent purified, polyclonal anti-CEA antibodies and planar scintigraphy, as the detection system. The second generation used I131 labeled monoclonal anti-CEA antibodies and SPECT, while the third generation employed I123 labeled fragments of monoclonal antibodies and SPECT. The improvement in the precision of tumor images with the most recent forms of immunoscintigraphy is obvious. However, we think the usefulness of immunoscintigraphy for routine cancer management has not yet been entirely demonstrated. Further prospective trials are still necessary to determine the precise clinical role of immunoscintigraphy. A case report is presented on a patient with two liver metastases from a sigmoid carcinoma, who received through the hepatic artery a therapeutic dose (100 mCi) of I131 coupled to 40 mg of a mixture of two high affinity anti-CEA monoclonal antibodies. Excellent localisation in the metastases of the I131 labeled antibodies was demonstrated by SPECT and the treatment was well tolerated. The irradiation dose to the tumor, however, was too low at 4300 rads (with 1075 rads to the normal liver and 88 rads to the bone marrow), and no evidence of tumor regression was obtained. Different approaches for increasing the irradiation dose delivered to the tumor by the antibodies are considered.
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Résumé La iododeoxyuridine (IdUrd), une fois marqué au 123I ou au 125I, est un agent potentiel pour des thérapies par rayonnements Auger. Cependant, des limitations restreignent son incorporation dans l'ADN. Afin d'augmenter celle-ci, différents groupes ont étudié la fluorodeoxyuridine (FdUrd), qui favorise l'incorporation d'analogue de la thymidine, sans toutefois parvenir à une toxicité associé plus importante. Dans notre approche, 3 lignées cellulaires de glioblastomes humains et une lignée de cancer ovarien ont été utilisées. Nous avons observé, 16 à 24 h après un court pré-traitement à la FdUrd, un fort pourcentage de cellules s'accumulant en phase S. Plus qu'une accumulation, c'était une synchronisation des cellules, celles-ci restant capables d'incorporer la radio-IdIrd et repartant dans le cycle cellulaire. De plus, ces cellules accumulées après un pré-traitement à la FdUrd étaient plus radio-sensibles. Après le même intervalle de 16 à 24 h suivant la FdUrd, les 4 lignées cellulaires ont incorporé des taux plus élevés de radio-IdUrd que sans ce prétraitement. Une corrélation temporelle entre l'accumulation des cellules en phase S et la forte incorporation de radio-IdUrd a ainsi été révélée 16 à 24 h après pré-traitement à la FdUrd. Les expériences de traitement par rayonnements Auger sur les cellules accumulées en phase S ont montré une augmentation significative de l'efficacité thérapeutique de 125I-IdUrd comparé aux cellules non prétraitées à la FdUrd. Une première estimation a permis de déterminer que 100 désintégrations de 125I par cellules étant nécessaires afin d'atteindre l'efficacité thérapeutique. De plus, p53 semble jouer un rôle dans l'induction directe de mort cellulaire après des traitements par rayonnements Auger, comme indiqué par les mesures par FACS d'apoptose et de nécrose 24 et 48 h après le traitement. Concernant les expériences in vivo, nous avons observé une incorporation marquée de la radio-IdUrd dans l'ADN après un pré-traitement à la FdUrd dans un model de carcinomatose ovarienne péritonéale. Une augmentation encore plus importante a été observée après injection intra-tumorale dans des transplants sous-cutanés de glioblastomes sur des souris nues. Ces modèles pourraient être utilisés pour de plus amples études de diffusion de radio-IdUrd et de thérapie par rayonnement Auger. En conclusion, ce travail montre une première application réussie de la FdUrd afin d'accroître l'efficacité de la radio-IdUrd par traitements aux rayonnements Auger. La synchronisation des cellules en phase S combinée avec la forte incorporation de radio-IdUrd dans l'ADN différées après un pré-traitement à la FdUrd ont montré le gain thérapeutique attendu in vitro. De plus, des études in vivo sont tout indiquées après les observations encourageantes d'incorporation de radio-IdUrd dans les models de transplants sous-cutanés de glioblastomes et de tumeurs péritonéales ovariennes. Summary Iododeoxyuridine (IdUrd), labelled with 123I or 125I, could be a potential Auger radiation therapy agent. However, limitations restrict its DNA incorporation in proliferating cells. Therefore, fluorodeoxyuridine (FdUrd), which favours incorporation of thymidine analogues, has been studied by different groups in order to increase radio-IdUrd DNA incorporation, however therapeutic efficacy increase could not be reached. In our approach, 3 human glioblastoma cell lines with different p53 expression and one ovarian cancer line were pre-treated with various FdUrd conditions. We observed a high percentage of cells accumulating in early S phase 16 to 24 h after a short and non-toxic FdUrd pre-treatment. More than an accumulation, this was a synchronization, cells remaining able to incorporate radio-IdUrd and re-entering the cell cycle. Furthermore, the S phase accumulated cells post FdUrd pre-treatment were more radiosensitive. After the same delay of 16 to 24 h post FdUrd pre-treatment, the 4 cell lines were incorporating higher rates of radio-IdUrd compared with untreated cells. A time correlation between S phase accumulation and high radio-IdUrd incorporation was therefore revealed 16 to 24 h post FdUrd pre-treatment. Auger radiation treatment experiments performed on S phase enriched cells showed a significant increase of killing efficacy of 125I-IdUrd compared with cells not pre-treated with FdUrd. A first estimation indicates further that about 100 125I decays were required to reach killing in the targeted cells. Moreover, p53 might play a role on the direct induction of cell death pathways after Auger radiation treatments, as indicated by differential apoptosis and necrosis induction measured by FACS 24 and 48 h after treatment initiation. Concerning in vivo results, we observed a marked DNA incorporation increase of radio-IdUrd after FdUrd pre-treatment in peritoneal carcinomatosis in SCID mice. Even higher incorporation increase was observed after intra-tumoural injection of radio-IdUrd in subcutaneous glioblastoma transplants in nude mice. These tumour models might be further useful for diffusion of radio-IdUrd and Auger radiation therapy studies. In conclusion, these data show a first successful application of thymidine synthesis inhibition able to increase the efficacy of radio-IdUrd Auger radiation treatment. The S phase synchronization combined with a high percentage DNA incorporation of radio-IdUrd delayed post FdUrd pre-treatment provided the expected therapeutic gain in vitro. Further in vivo studies are indicated after the observations of encouraging radio-IdUrd uptake experiments in glioblastoma subcutaneous xenografts and in an ovarian peritoneal carcinomatosis model.