923 resultados para PREFRONTAL GRAY


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Malignant pleural mesothelioma (MPM) is a rare aggressive cancer of the pleura. Asbestos exposure (through inhalation) is the most well established risk factor for mesothelioma. The current standard of care for patients suffering from MPM is a combination of cisplatin and pemetrexed (or alternatively cisplatin and raltitrexed). Most patients, however, die within 24 months of diagnosis. New therapies are therefore urgently required for this disease. Lysine acetyltransferases (KATs) including KAT5 have been linked with the development of cisplatin resistance. This gene may therefore be altered in MPM and could represent a novel candidate target for intervention. Using RT-PCR screening the expression of all known KAT5 variants was found to be markedly increased in malignant tumors compared to benign pleura. When separated according to histological subtype, KAT5 was significantly overexpressed in both the sarcomatoid and biphasic subgroups for all transcript variants. A panel of MPM cell lines including the normal pleural cells LP9 and Met5A was screened for expression of KAT5 variants. Treatment of cells with a small molecule inhibitor of KAT5 (MG-149) caused significant inhibition of cellular proliferation (p<0.0001), induction of apoptosis and was accompanied by significant induction of pro-inflammatory cytokines/chemokines.

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Thoracic malignancies present a considerable global health burden with the incidence and mortality of both lung cancer and malignant pleural mesothelioma (MPM) increasing year on year. Survival rates are poor and treatment options are limited in these cancers. Several epigenetic modifications have been associated with the development of both of these diseases with alterations discriminating between MPM and adenocarcinoma (AC) of the lung. In addition, studies have suggested that epigenetic agents are effective in altering the cellular characteristics of lung and MPM cells in terms of proliferation and migration. Furthermore, it has been demonstrated that epigenetic therapy can alter a pathologically relevant gene expression profile, with one that is more associated with comparative normal tissue. Therefore agents, which target the epi-genomes of lung cancer and MPM, may provide a substantial therapeutic improvement when used in combination with current therapy or indeed benefit when used as a single treatment modality.

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Aims: To evaluate the potential therapeutic utility of histone deacetylase inhibitors (HDACi) in targeting VEGF receptors in non-small-cell lung cancer. Materials & methods: Non-small-cell lung cancer cells were screened for the VEGF receptors at the mRNA and protein levels, while cellular responses to various HDACi were examined. Results: Significant effects on the regulation of the VEGF receptors were observed in response to HDACi. These were associated with decreased secretion of VEGF, decreased cellular proliferation and increased apoptosis which could not be rescued by addition of exogenous recombinant VEGF. Direct remodeling of the VEGFR1 and VEGFR2 promoters was observed. In contrast, HDACi treatments resulted in significant downregulation of the Neuropilin receptors. Conclusion: Epigenetic targeting of the Neuropilin receptors may offer an effective treatment for lung cancer patients in the clinical setting.

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The insulin‑like growth factor 1 receptor (IGF1R) pathway plays an important role in the pathogenesis of non‑small cell lung cancer (NSCLC) and also provides a mechanism of resistance to targeted therapies. IGF1R is therefore an ideal therapeutic target and several inhibitors have entered clinical trials. However, thus far the response to these inhibitors has been poor, highlighting the importance of predictive biomarkers to identify patient cohorts who will benefit from these targeted agents. It is well‑documented that mutations and/or deletions in the epidermal growth factor receptor (EGFR) tyrosine kinase (TK) domain predict sensitivity of NSCLC patients to EGFR TK inhibitors. Single‑nucleotide polymorphisms (SNPs) in the IGF pathway have been associated with disease, including breast and prostate cancer. The aim of the present study was to elucidate whether the IGF1R TK domain harbours SNPs, somatic mutations or deletions in NSCLC patients and correlates the mutation status to patient clinicopathological data and prognosis. Initially 100 NSCLC patients were screened for mutations/deletions in the IGF1R TK domain (exons 16‑21) by sequencing analysis. Following the identification of SNP rs2229765, a further 98 NSCLC patients and 866 healthy disease‑free control patients were genotyped using an SNP assay. The synonymous SNP (rs2229765) was the only aberrant base change identified in the IGF1R TK domain of 100 NSCLC patients initially analysed. SNP rs2229765 was detected in exon 16 and was found to have no significant association between IGF1R expression and survival. The GA genotype was identified in 53.5 and 49.4% of NSCLC patients and control individuals, respectively. No significant difference was found in the genotype (P=0.5487) or allele (P=0.9082) frequencies between the case and control group. The present findings indicate that in contrast to the EGFR TK domain, the IGF1R TK domain is not frequently mutated in NSCLC patients. The synonymous SNP (rs2229765) had no significant association between IGF1R expression and survival in the cohort of NSCLC patients.

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Following market reforms in 1986 Vietnam has transformed from a poor closed economy to a low middle income economy. Like other developing countries, economic growth has placed significant pressure on both infrastructure and environment, particularly the pressure of increasing housing demand, energy consumption, and waste and pollution management. In response to the development challenges and the green movement globally, the government has initiated actions to promote green building to promote more sustainable development. However, green building adoption in Vietnam is still criticised as being slow and lacking governmental support. This paper proposes that promoting green building could solve three inter-connected challenges hindering sustainable development, and provides a comparative review of progress.

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Rather than a single focus on assessing risk and diagnosing deficit, this book recognises that our child protection systems bear down disproportionately on those from disadvantaged and marginalised communities and argues that what is needed is real support and practical assistance for poor and vulnerable parents and children. It uses real-world case examples to illustrate the relevant ethical and practice principles, and ways in which students and practitioners can practise ethically when dealing with complex, multi-faceted issues.

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The problem of constructing space-time (ST) block codes over a fixed, desired signal constellation is considered. In this situation, there is a tradeoff between the transmission rate as measured in constellation symbols per channel use and the transmit diversity gain achieved by the code. The transmit diversity is a measure of the rate of polynomial decay of pairwise error probability of the code with increase in the signal-to-noise ratio (SNR). In the setting of a quasi-static channel model, let n(t) denote the number of transmit antennas and T the block interval. For any n(t) <= T, a unified construction of (n(t) x T) ST codes is provided here, for a class of signal constellations that includes the familiar pulse-amplitude (PAM), quadrature-amplitude (QAM), and 2(K)-ary phase-shift-keying (PSK) modulations as special cases. The construction is optimal as measured by the rate-diversity tradeoff and can achieve any given integer point on the rate-diversity tradeoff curve. An estimate of the coding gain realized is given. Other results presented here include i) an extension of the optimal unified construction to the multiple fading block case, ii) a version of the optimal unified construction in which the underlying binary block codes are replaced by trellis codes, iii) the providing of a linear dispersion form for the underlying binary block codes, iv) a Gray-mapped version of the unified construction, and v) a generalization of construction of the S-ary case corresponding to constellations of size S-K. Items ii) and iii) are aimed at simplifying the decoding of this class of ST codes.

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A detailed study is presented of the expected performance of the ATLAS detector. The reconstruction of tracks, leptons, photons, missing energy and jets is investigated, together with the performance of b-tagging and the trigger. The physics potential for a variety of interesting physics processes, within the Standard Model and beyond, is examined. The study comprises a series of notes based on simulations of the detector and physics processes, with particular emphasis given to the data expected from the first years of operation of the LHC at CERN.

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For active contour modeling (ACM), we propose a novel self-organizing map (SOM)-based approach, called the batch-SOM (BSOM), that attempts to integrate the advantages of SOM- and snake-based ACMs in order to extract the desired contours from images. We employ feature points, in the form of ail edge-map (as obtained from a standard edge-detection operation), to guide the contour (as in the case of SOM-based ACMs) along with the gradient and intensity variations in a local region to ensure that the contour does not "leak" into the object boundary in case of faulty feature points (weak or broken edges). In contrast with the snake-based ACMs, however, we do not use an explicit energy functional (based on gradient or intensity) for controlling the contour movement. We extend the BSOM to handle extraction of contours of multiple objects, by splitting a single contour into as many subcontours as the objects in the image. The BSOM and its extended version are tested on synthetic binary and gray-level images with both single and multiple objects. We also demonstrate the efficacy of the BSOM on images of objects having both convex and nonconvex boundaries. The results demonstrate the superiority of the BSOM over others. Finally, we analyze the limitations of the BSOM.

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Pro gradu -tutkielmassani tarkastelen diasporia ja niihin kohdistuvaa kansainvälistä sääntelyä. Diasporilla tarkoitan valtion rajojen ulkopuolella asuvia ihmisiä, joilla on jokin, esimerkiksi etninen tai kieliside tuohon valtioon. Valtiolla puolestaan voi olla jokin intressi suhteessa diasporaansa. Diasporiin liittyvät kysymykset ovat ajankohtaisia globaalissa maailmassa, jossa ihmisillä on entistä enemmän mahdollisuuksia pitää siteitä yllä useampaan kuin yhteen valtioon. Diasporien ohella kirjallisuudessa puhutaan myös kin-state -problematiikasta, kun viitataan valtioiden harjoittamaan politiikkaan, joka pyrkii vaikuttamaan toisen valtion alueella asuvien tai oleskelevien ihmisten asemaan. Tutkimuksen teoreettinen viitekehys on englantilaisen koulukunnan ajatus kansainvälisestä yhteisöstä ja sille keskeisistä primaari-instituutioista, kuten valtiosuvereniteetti ja kansainvälinen oikeus. Se, miten valtio politiikassaan suhtautuu instituutioihin, kertoo valtion suhteesta kansainväliseen yhteisöön yleensä. Instituutioita voidaan puolestaan tarkastella tiettyjen kapea-alaisempien normien, sekundaari-instituutioiden, valossa. Edellä mainittuna sekundaari-instituutiona esitellään tutkielmassa se kansainvälinen normisto, joka vaikuttaa diasporien asemaan valtioiden välisessä politiikassa. Normisto perustuu Yhdistyneiden kansakuntien, Euroopan neuvoston ja ETYJ:n sopimuksiin ja suosituksiin. Kansainvälisen oikeuden lähtökohta on, ettei valtio voi puuttua diasporakseen katsomiensa ihmisten asemaan toisessa valtiossa edes ääritapauksessa, jossa asuinvaltio epäonnistuu tehtävässään suojella toisen valtion kansalaisia tai vähemmistöjään. Reagointivastuu on kansainvälisellä yhteisöllä – vaikka interventiota ulkomailla olevien kansalaisten suojelemiseksi onkin suoritettu sekä kylmän sodan aikana että sen jälkeen. Interventiot eivät ole diasporapolitiikan ainoa muoto ja monilla valtioilla onkin niin sanottuja diasporalakeja, joiden puitteissa ne voivat vaikuttaa diasporiensa asemaan. Koulutukseen ja kulttuuriin liittyvä tuki on eurooppalaisissa suosituksissa katsottu hyväksyttäväksi, mutta muiden tukimuotojen ulottamista diasporiin tulee harkita ja soveltaa vain erityistapauksissa, jos politiikalla on valtion toimivallan ulkopuolella vaikuttavia seurauksia. Tutkimus näyttää, että diasporakysymysten sääntely on kansainvälisessä yhteisössä vielä osin määrittelemätöntä sekä altista valtioiden tulkinnoille. Esimerkkinä valtioiden tulkinnoista ja niiden harjoittamasta diasporapolitiikasta tarkastellaan Venäjän federaation politiikkaa, sillä Venäjän ulkopolitiikassa esillä pidetty kiinnostus suojella ulkomailla olevia kansalaisia ja maanmiehiä on herättänyt myös kansainvälistä huomiota. Venäjän politiikan tarkastelu luo kontekstin, jossa tutkielman varsinaista kiinnostuksenkohdetta, Suomen venäläisen diasporan asemaa, on mahdollista tarkastella. Tutkimusaineistoa ovat Venäjän johdon lausunnot liittyen viimeaikaisiin Suomen ja Venäjän välisiin nk. lapsikiistoihin. Teoriaohjaava sisällönanalyysi aineistosta esittää, että vaikka vihjeitä politiikassa yleisesti esiintyvästä nk. suojelupuheesta on havaittavissa myös Suomen venäläisen vähemmistön asemaan liittyen, ei Venäjä lapsikiistoissa kuitenkaan suoraan loukannut Suomen suvereniteettia tai kansainvälistä oikeutta. Tiettyjen puhetapojen ja esimerkiksi lapsiasiamies Astahovin toiminnan voidaan kuitenkin tulkita olevan kansainvälisen normiston vastaisia ja siten myös loukkaavan suvereniteettia ja kansainvälisen oikeuden henkeä. Teoreettisen viitekehyksen tehtävä oli ensisijaisesti antaa näkökulmia aineiston tarkasteluun. Venäjän politiikan suhde suvereniteettiin ja kansainväliseen oikeuteen suhteessa tässä tarkasteltuun politiikkakysymykseen kertoo kuitenkin myös Venäjän asemasta kansainvälisen yhteisön jäsenenä. Diasporanormistoon sitoutuminen osoittaa Venäjän sitoutuneen ainakin periaatteellisella tasolla solidaristiseen, yhteisiä normeja jakavaan kansainväliseen yhteisöön – toisaalta Venäjän viime vuosien politiikka kuitenkin osoittaa Venäjän samalla haastavan myös pluralistisille yhteisöille keskeisiä valtiosuvereniteetin ja kansainvälisen oikeuden noudattamisen periaatteita. Tärkeimmät lähteet: Buzan (2004), Brubakers (1995), Hannikainen (2000), Holsti (2004), Gazzini (2005), Gray (2000), Kántor ym. (2004), Sheffer (2003), Shevel (2010 ja 2011), Turner ja Otsuki (2010) ja Zevelev (2001 ja 2008).

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Multisensor recordings are becoming commonplace. When studying functional connectivity between different brain areas using such recordings, one defines regions of interest, and each region of interest is often characterized by a set (block) of time series. Presently, for two such regions, the interdependence is typically computed by estimating the ordinary coherence for each pair of individual time series and then summing or averaging the results over all such pairs of channels (one from block 1 and other from block 2). The aim of this paper is to generalize the concept of coherence so that it can be computed for two blocks of non-overlapping time series. This quantity, called block coherence, is first shown mathematically to have properties similar to that of ordinary coherence, and then applied to analyze local field potential recordings from a monkey performing a visuomotor task. It is found that an increase in block coherence between the channels from V4 region and the channels from prefrontal region in beta band leads to a decrease in response time.

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A comprehensive scheme has been developed for the prediction of radiation from engine exhaust and its incidence on an arbitrarily located sensor. Existing codes have been modified for the simulation of flows inside nozzles and jets. A novel view factor computation scheme has been applied for the determination of the radiosities of the discrete panels of a diffuse and gray nozzle surface. The narrowband model has been used to model the radiation from the gas inside the nozzle and the nonhomogeneous jet. The gas radiation from the nozzle inclusive of nozzle surface radiosities have been used as boundary conditions on the jet radiation. Geometric modeling techniques have been developed to identify and isolate nozzle surface panels and gas columns of the nozzle and jet to determine the radiation signals incident on the sensor. The scheme has been validated for intensity and heat flux predictions, and some useful results of practical importance have been generated to establish its viability for infrared signature analysis of jets.

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Existing approches to digital halftoning of image are based primarily on thresholding. We propose a general framework fot image halftoning whcrc some function uf the output halftone tracks another function of the input gray-tone.This appcoach is shown lo unify most existing algorithms and to provide useful insights. Further, the new intcrpretation allows us to remedy problems in existing aigorithrms such as the error dlffusion, and sohsequently to achieve halftones haavmg superior quality. The proposed method is very general nature is an advantage since it offers a wide choice of three Cilters and a update rule. An intercstmg product of this framework is that equally good, or better, half-tones are possible ro be obtained by thresholding a noise proccess instead of the image itself.

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Learning your αβγ's: The diversity of hydrogen-bonding patterns in backbone-expanded hybrid helices is shown by crystal-structure determination of several oligomeric peptides (see scheme; C=gray; H=white; O=red; N=blue). C 12 helices were observed in the αγ peptide series for n=2-8. In comparison, the αα peptide and αβ peptide sequences show C 10 and mixed C 14/C 15 helices, respectively. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.