805 resultados para MP3 (Audio coding standard)
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Recent experiments have established that information can be encoded in the spike times of neurons relative to the phase of a background oscillation in the local field potential—a phenomenon referred to as “phase-of-firing coding” (PoFC). These firing phase preferences could result from combining an oscillation in the input current with a stimulus-dependent static component that would produce the variations in preferred phase, but it remains unclear whether these phases are an epiphenomenon or really affect neuronal interactions—only then could they have a functional role. Here we show that PoFC has a major impact on downstream learning and decoding with the now well established spike timing-dependent plasticity (STDP). To be precise, we demonstrate with simulations how a single neuron equipped with STDP robustly detects a pattern of input currents automatically encoded in the phases of a subset of its afferents, and repeating at random intervals. Remarkably, learning is possible even when only a small fraction of the afferents (~10%) exhibits PoFC. The ability of STDP to detect repeating patterns had been noted before in continuous activity, but it turns out that oscillations greatly facilitate learning. A benchmark with more conventional rate-based codes demonstrates the superiority of oscillations and PoFC for both STDP-based learning and the speed of decoding: the oscillation partially formats the input spike times, so that they mainly depend on the current input currents, and can be efficiently learned by STDP and then recognized in just one oscillation cycle. This suggests a major functional role for oscillatory brain activity that has been widely reported experimentally.
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INTRODUCTION: Intrauterine Growth Restriction (IUGR) is a multifactorial disease defined by an inability of the fetus to reach its growth potential. IUGR not only increases the risk of neonatal mortality/morbidity, but also the risk of metabolic syndrome during adulthood. Certain placental proteins have been shown to be implicated in IUGR development, such as proteins from the GH/IGF axis and angiogenesis/apoptosis processes. METHODS: Twelve patients with term IUGR pregnancy (birth weight < 10th percentile) and 12 CTRLs were included. mRNA was extracted from the fetal part of the placenta and submitted to a subtraction method (Clontech PCR-Select cDNA Subtraction). RESULTS: One candidate gene identified was the long non-coding RNA NEAT1 (nuclear paraspeckle assembly transcript 1). NEAT1 is the core component of a subnuclear structure called paraspeckle. This structure is responsible for the retention of hyperedited mRNAs in the nucleus. Overall, NEAT1 mRNA expression was 4.14 (±1.16)-fold increased in IUGR vs. CTRL placentas (P = 0.009). NEAT1 was exclusively localized in the nuclei of the villous trophoblasts and was expressed in more nuclei and with greater intensity in IUGR placentas than in CTRLs. PSPC1, one of the three main proteins of the paraspeckle, co-localized with NEAT1 in the villous trophoblasts. The expression of NEAT1_2 mRNA, the long isoform of NEAT1, was only modestly increased in IUGR vs. CTRL placentas. DISCUSSION/CONCLUSION: The increase in NEAT1 and its co-localization with PSPC1 suggests an increase in paraspeckles in IUGR villous trophoblasts. This could lead to an increased retention of important mRNAs in villous trophoblasts nuclei. Given that the villous trophoblasts are crucial for the barrier function of the placenta, this could in part explain placental dysfunction in idiopathic IUGR fetuses.
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BACKGROUND: The outcome of diffuse large B-cell lymphoma has been substantially improved by the addition of the anti-CD20 monoclonal antibody rituximab to chemotherapy regimens. We aimed to assess, in patients aged 18-59 years, the potential survival benefit provided by a dose-intensive immunochemotherapy regimen plus rituximab compared with standard treatment plus rituximab. METHODS: We did an open-label randomised trial comparing dose-intensive rituximab, doxorubicin, cyclophosphamide, vindesine, bleomycin, and prednisone (R-ACVBP) with subsequent consolidation versus standard rituximab, doxorubicin, cyclophosphamide, vincristine, and prednisone (R-CHOP). Random assignment was done with a computer-assisted randomisation-allocation sequence with a block size of four. Patients were aged 18-59 years with untreated diffuse large B-cell lymphoma and an age-adjusted international prognostic index equal to 1. Our primary endpoint was event-free survival. Our analyses of efficacy and safety were of the intention-to-treat population. This study is registered with ClinicalTrials.gov, number NCT00140595. FINDINGS: One patient withdrew consent before treatment and 54 did not complete treatment. After a median follow-up of 44 months, our 3-year estimate of event-free survival was 81% (95% CI 75-86) in the R-ACVBP group and 67% (59-73) in the R-CHOP group (hazard ratio [HR] 0·56, 95% CI 0·38-0·83; p=0·0035). 3-year estimates of progression-free survival (87% [95% CI, 81-91] vs 73% [66-79]; HR 0·48 [0·30-0·76]; p=0·0015) and overall survival (92% [87-95] vs 84% [77-89]; HR 0·44 [0·28-0·81]; p=0·0071) were also increased in the R-ACVBP group. 82 (42%) of 196 patients in the R-ACVBP group experienced a serious adverse event compared with 28 (15%) of 183 in the R-CHOP group. Grade 3-4 haematological toxic effects were more common in the R-ACVBP group, with a higher proportion of patients experiencing a febrile neutropenic episode (38% [75 of 196] vs 9% [16 of 183]). INTERPRETATION: Compared with standard R-CHOP, intensified immunochemotherapy with R-ACVBP significantly improves survival of patients aged 18-59 years with diffuse large B-cell lymphoma with low-intermediate risk according to the International Prognostic Index. Haematological toxic effects of the intensive regimen were raised but manageable. FUNDING: Groupe d'Etudes des Lymphomes de l'Adulte and Amgen.
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American English exhibits a great dialectal diversity, easily perceived in lexicon; so that questions are raised about which regionalisms are part of the mythical SAE and which are not. A small sample of regionalisms is checked against three standard dictionaries in order to determine the role regionalisms play in SAE.
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When certain control parameters of nervous cell models are varied, complex bifurcation structures develop in which the dynamical behaviors available appear classified in blocks, according to criteria of dynamical likelihood. This block structured dynamics may be a clue to understand how activated neurons encode information by firing spike trains of their action potentials.
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PURPOSE: To evaluate the safety and efficacy of an intravitreal fluocinolone acetonide (FA) implant compared with standard therapy in subjects with noninfectious posterior uveitis (NIPU). DESIGN: Randomized, controlled, phase 2b/3, open-label, multicenter superiority trial. PARTICIPANTS: Subjects with unilateral or bilateral NIPU. METHODS: One hundred forty subjects received either a 0.59-mg FA intravitreal implant (n = 66) or standard of care (SOC; n = 74) with either systemic prednisolone or equivalent corticosteroid as monotherapy (> or =0.2 mg/kg daily) or, if judged necessary by the investigator, combination therapy with an immunosuppressive agent plus a lower dose of prednisolone or equivalent corticosteroid (> or =0.1 mg/kg daily). MAIN OUTCOME MEASURES: Time to first recurrence of uveitis. RESULTS: Eyes that received the FA intravitreal implant experienced delayed onset of observed recurrence of uveitis (P<0.01) and a lower rate of recurrence of uveitis (18.2% vs. 63.5%; P< or =0.01) compared with SOC study eyes. Adverse events frequently observed in implanted eyes included elevated intraocular pressure (IOP) requiring IOP-lowering surgery (occurring in 21.2% of implanted eyes) and cataracts requiring extraction (occurring in 87.8% of phakic implanted eyes). No treatment-related nonocular adverse events were observed in the implant group, whereas such events occurred in 25.7% of subjects in the SOC group. CONCLUSIONS: The FA intravitreal implant provided better control of inflammation in patients with uveitis compared with systemic therapy. Intraocular pressure and lens clarity of implanted eyes need close monitoring in patients receiving the FA intravitreal implant.
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Many audio watermarking schemes divide the audio signal into several blocks such that part of the watermark is embedded into each of them. One of the key issues in these block-oriented watermarking schemes is to preserve the synchronisation, i.e. to recover the exact position of each block in the mark recovery process. In this paper, a novel time domain synchronisation technique is presented together with a new blind watermarking scheme which works in the Discrete Fourier Transform (DFT or FFT) domain. The combined scheme provides excellent imperceptibility results whilst achieving robustness against typical attacks. Furthermore, the execution of the scheme is fast enough to be used in real-time applications. The excellent transparency of the embedding algorithm makes it particularly useful for professional applications, such as the embedding of monitoring information in broadcast signals. The scheme is also compared with some recent results of the literature.
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Tutkielman tavoitteena on rakentaa toimiva ympäristöjärjestelmä Thermo Fisher Scientific Oy:lle. Tutkimuksen tarkoituksena on myös löytää kahdelle täysin erilaiselle toiminnalle yhtenäinen ympäristöjärjestelmä, jonka avulla pystytään ottamaan huomioon molempien toimipaikkojen hieman erilaiset vaatimukset. Lisäksi tavoitteena on muodostaa ympäristöjärjestelmälle oma organisaatio, jonka avulla ympäristöjärjestelmän integrointi yrityksen prosesseihin voidaan suorittaa sujuvasti. Aluksi tutkimusongelmaa lähestytään teoreettisesta näkökulmasta,jossa tarkastellaan ympäristöjärjestelmän historiaa, rakennetta, etuja sekä ISO 14001–standardin rakennetta ja sen etenemistä ympäristöjärjestelmän rakentamisen yhteydessä aina kolmannen osapuolen sertifiointiin asti. Empiria osa alkaa alustavalla ympäristökatselmuksella, jossa selvitetään ympäristöasioiden hoidon nykytaso ja luodaan pohja koko ympäristöjärjestelmän luomiselle, jonka vankimpana perustana on ympäristöpolitiikka. Johdon hyväksymä ympäristöpolitiikka varmistaa johdon sitoutumisen järjestelmään. Ympäristöjärjestelmän toimintarakenteen muodostaminen kahdelle erilaiselle toiminnalle onnistui tutkimuksessa kiitettävästi. Se miten ympäristöjärjestelmä toimii todellisuudessa, tullaan näkemään käytännön kokemuksien yhteydessä.
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Cooperative transmission can be seen as a "virtual" MIMO system, where themultiple transmit antennas are in fact implemented distributed by the antennas both at the source and the relay terminal. Depending on the system design, diversity/multiplexing gainsare achievable. This design involves the definition of the type of retransmission (incrementalredundancy, repetition coding), the design of the distributed space-time codes, the errorcorrecting scheme, the operation of the relay (decode&forward or amplify&forward) and thenumber of antennas at each terminal. Proposed schemes are evaluated in different conditionsin combination with forward error correcting codes (FEC), both for linear and near-optimum(sphere decoder) receivers, for its possible implementation in downlink high speed packetservices of cellular networks. Results show the benefits of coded cooperation over directtransmission in terms of increased throughput. It is shown that multiplexing gains areobserved even if the mobile station features a single antenna, provided that cell wide reuse of the relay radio resource is possible.
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BACKGROUND: Medication adherence has been identified as an important factor for clinical success. Twenty-four Swiss community pharmacists participated in the implementation of an adherence support programme for patients with hypertension, diabetes mellitus and/or dyslipidemia. The programme combined tailored consultations with patients about medication taking (expected at an average of one intervention per month) and the delivery of each drug in an electronic monitoring system (MEMS6?). OBJECTIVE: To explore pharmacists' perceptions and experiences with implementation of the medication adherence programme and to clarify why only seven patients were enrolled in total. SETTING: Community pharmacies in French-speaking Switzerland. METHOD: Individual in-depth interviews were audio-recorded, with 20 of the pharmacists who participated in the adherence programme. These were transcribed verbatim, coded and thematically analysed. Process quality was ensured by using an audit trail detailing the development of codes and themes; furthermore, each step in the coding and analysis was verified by a second, experienced qualitative researcher. MAIN OUTCOME MEASURE: Community pharmacists' experiences and perceptions of the determining factors influencing the implementation of the adherence programme. RESULTS: Four major barriers were identified: (1) poor communication with patients resulting in insufficient promotion of the programme; (2) insufficient collaboration with physicians; (3) difficulty in integrating the programme into pharmacy organisation; and (4) insufficient pharmacist motivation. This was related to the remuneration perceived as insufficient and to the absence of clear strategic thinking about the pharmacist position in the health care system. One major facilitator of the programme's implementation was pre-existing collaboration with physicians. CONCLUSION: A wide range of barriers was identified. The implementation of medication adherence programmes in Swiss community pharmacies would benefit from an extended training aimed at developing communication and change management skills. Individualised onsite support addressing relevant barriers would also be necessary throughout the implementation process.
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Toiminnanohjausjärjestelmän implementointi ja sen mukanaan tuomat muutokset tuotekustannuslaskentaan asettavat haasteita yritykselle. Metallitoimialalla toimivassa yrityksessä on havaittu samat haasteet implementoitaessa SAP R/3 toiminnanohjausjärjestelmää ja sen tuotekustannuslaskentatoiminnallisuutta. SAP R/3 tuotekustannuslogiikka tarvitsee tietoa järjestelmän ulkopuolelta, minkä huomioimatta jättäminen vaikuttaa suoraan laskentatarkkuuteen. Diplomityössä kehitetään sekä standardoitu prosessi että laskentajärjestelmä, joiden avulla pystytään laskemaan tarvittavat niin toimintokustannukset eri teräspalvelukeskuksen kuormituspisteille kuin kustannustenvyörytysarvot. Lasketut arvot muodostavat tarvittavat tekijät SAP R/3 tuotekustannuslaskennan master dataan. Tavoitteena on edesauttaa läpinäkyvän kustannustiedon muodostumista. Diplomityö pohjautuu ns. vesiputousmalliin (SDLC). Ensin tunnistetaan reunaehdot ympäristöstä, jossa tuotekustannuslaskenta toteutetaan. Tämä asettaa joustamattomia komponentteja kehitettävälle laskentajärjestelmälle. Joustavat komponentit sen sijaan antavat vapautta laskentajärjestelmälle. Yhdistämällä joustamattomat ja joustavat komponentit saavutetaan järjestelmä, jolla voidaan täydentää SAP R/3 tuotekustannuslaskennan puutteellisuutta.
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INTRODUCTION: A significant proportion of prematurely born children encounter behavioral difficulties, such as attention deficit or hyperactivity, which could be due to executive function disorders. AIMS: To examine whether the standard neurodevelopmental assessment offered to premature children in Switzerland recognizes executive function disorders. METHODS: The study population consisted of 49 children born before 29 weeks of gestation who were examined between 5 and 6 years of age with a standard assessment, with additional items to assess executive functioning. Children with severe neurodevelopmental impairment were excluded (mental retardation, cerebral palsy, autism). Standard assessment consisted in the Kaufman Assessment Battery for Children (K-ABC), which comprises three subscales: sequential processes (analysis of sequential information), simultaneous processes (global analysis of visual information), and composite mental processes (CMP) (result of the other two scales), as well as a behavioral evaluation using the standardized Strengths and Difficulties Questionnaire (SDQ). Executive functioning was assessed with tasks evaluating visual attention, divided attention, and digit memory as well as with a specialized questionnaire, the Behavior Rating Index of Executive Functions (BRIEF), which evaluates several aspects of executive function (regulation, attention, flexibility, working memory, etc). RESULTS: Children were divided according to their results on the three K-ABC scales (< or>85), and the different neuropsychological tasks assessing executive function were compared between the groups. The CMP did not differentiate children with executive difficulties, whereas a score<85 on the sequential processes was significantly associated with worse visual and divided attention. There was a strong correlation between the SDQ and the BRIEF questionnaires. For both questionnaires, children receiving psychotherapy had significantly higher results. Children who presented behavioral problems assessed with the SDQ presented significantly higher scores on the BRIEF. CONCLUSION: A detailed analysis of the standard neurodevelopmental assessment allows the identification of executive function disorders in premature children. Children who performed below 85 on the sequential processes of the K-ABC had significantly more attentional difficulties on the neuropsychological tasks and therefore have to be recognized and carefully followed. Emotional regulation had a strong correlation with behavioral difficulties, which were suitably assessed with the SDQ, recognized by the families, and treated.
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AIM: Heart disease is recognized as a consequence of dysregulation of cardiac gene regulatory networks. Previously, unappreciated components of such networks are the long non-coding RNAs (lncRNAs). Their roles in the heart remain to be elucidated. Thus, this study aimed to systematically characterize the cardiac long non-coding transcriptome post-myocardial infarction and to elucidate their potential roles in cardiac homoeostasis. METHODS AND RESULTS: We annotated the mouse transcriptome after myocardial infarction via RNA sequencing and ab initio transcript reconstruction, and integrated genome-wide approaches to associate specific lncRNAs with developmental processes and physiological parameters. Expression of specific lncRNAs strongly correlated with defined parameters of cardiac dimensions and function. Using chromatin maps to infer lncRNA function, we identified many with potential roles in cardiogenesis and pathological remodelling. The vast majority was associated with active cardiac-specific enhancers. Importantly, oligonucleotide-mediated knockdown implicated novel lncRNAs in controlling expression of key regulatory proteins involved in cardiogenesis. Finally, we identified hundreds of human orthologues and demonstrate that particular candidates were differentially modulated in human heart disease. CONCLUSION: These findings reveal hundreds of novel heart-specific lncRNAs with unique regulatory and functional characteristics relevant to maladaptive remodelling, cardiac function and possibly cardiac regeneration. This new class of molecules represents potential therapeutic targets for cardiac disease. Furthermore, their exquisite correlation with cardiac physiology renders them attractive candidate biomarkers to be used in the clinic.