983 resultados para Local phase quantization


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Trench maintenance problems are caused by improper backfill placement and construction procedures. This report is part of a multiphase research project that aims to improve long-term performance of utility cut restoration trenches. The goal of this research is to improve pavement patch life and reduce maintenance of the repaired areas. The objectives were to use field-testing data, laboratory-testing data, and long-term monitoring (elevation survey and falling weight deflectometer testing) to suggest and modify recommendations from Phase I and to identify the principles of trench subsurface settlement and load distribution in utility cut restoration areas by using instrumented trenches. The objectives were accomplished by monitoring local agency utility construction from Phase I, constructing and monitoring the recommended trenches from Phase I, and instrumenting trenches to monitor changes in temperature, pressure, moisture content, and settlement as a function of time to determine the influences of seasonal changes on the utility cut performance.

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A prior project, HR-388, (which was entitled "Total Cost of Transportation analysis of road and highway issues"), explored the use of a total economic cost basis for evaluation of road based transportation issues. It was conducted as a proof-of-concept effort between 1996 and 2002, with the final report presented in May 2002. TR-477 rebuilt the analytical model using current data, then performed general, system level, county level, and road segment level analyses. The results are presented herein and will be distributed to all county engineers for information and local use.

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Three pavement design software packages were compared with regards to how they were different in determining design input parameters and their influences on the pavement thickness. StreetPave designs the concrete pavement thickness based on the PCA method and the equivalent asphalt pavement thickness. The WinPAS software performs both concrete and asphalt pavements following the AASHTO 1993 design method. The APAI software designs asphalt pavements based on pre-mechanistic/empirical AASHTO methodology. First, the following four critical design input parameters were identified: traffic, subgrade strength, reliability, and design life. The sensitivity analysis of these four design input parameters were performed using three pavement design software packages to identify which input parameters require the most attention during pavement design. Based on the current pavement design procedures and sensitivity analysis results, a prototype pavement design and sensitivity analysis (PD&SA) software package was developed to retrieve the pavement thickness design value for a given condition and allow a user to perform a pavement design sensitivity analysis. The prototype PD&SA software is a computer program that stores pavement design results in database that is designed for the user to input design data from the variety of design programs and query design results for given conditions. The prototype Pavement Design and Sensitivity Analysis (PA&SA) software package was developed to demonstrate the concept of retrieving the pavement design results from the database for a design sensitivity analysis. This final report does not include the prototype software which will be validated and tested during the next phase.

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Mixture materials, mix design, and pavement construction are not isolated steps in the concrete paving process. Each affects the other in ways that determine overall pavement quality and long-term performance. However, equipment and procedures commonly used to test concrete materials and concrete pavements have not changed in decades, leaving gaps in our ability to understand and control the factors that determine concrete durability. The concrete paving community needs tests that will adequately characterize the materials, predict interactions, and monitor the properties of the concrete. The overall objectives of this study are (1) to evaluate conventional and new methods for testing concrete and concrete materials to prevent material and construction problems that could lead to premature concrete pavement distress and (2) to examine and refine a suite of tests that can accurately evaluate concrete pavement properties. The project included three phases. In Phase I, the research team contacted each of 16 participating states to gather information about concrete and concrete material tests. A preliminary suite of tests to ensure long-term pavement performance was developed. The tests were selected to provide useful and easy-to-interpret results that can be performed reasonably and routinely in terms of time, expertise, training, and cost. The tests examine concrete pavement properties in five focal areas critical to the long life and durability of concrete pavements: (1) workability, (2) strength development, (3) air system, (4) permeability, and (5) shrinkage. The tests were relevant at three stages in the concrete paving process: mix design, preconstruction verification, and construction quality control. In Phase II, the research team conducted field testing in each participating state to evaluate the preliminary suite of tests and demonstrate the testing technologies and procedures using local materials. A Mobile Concrete Research Lab was designed and equipped to facilitate the demonstrations. This report documents the results of the 16 state projects. Phase III refined and finalized lab and field tests based on state project test data. The results of the overall project are detailed herein. The final suite of tests is detailed in the accompanying testing guide.

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This report describes the first phase in a project to develop an electronic reference library (ERL) to help Iowa transportation officials efficiently access information in critical and heavily used documents. These documents include Standard Specifications for Bridge and Highway Construction (hereinafter called Standard Specifications), design manuals, standard drawings, the Construction Manual, and Material Instruction Memoranda (hereinafter called Material IMs). Additional items that could be included to enhance the ERL include phone books, letting dates, Internet links, computer programs distributed by the Iowa Department of Transportation (DOT), and local specifications, such as the Urban Standard Specifications of Public Improvements. All cross-references should be hyper linked, and a search engine should be provided. Revisions noted in the General Supplemental Specifications (hereinafter called the Supplemental Specifications) should be incorporated into the text of the Standard Specifications. The Standard Specifications should refer to related sections of other documents, and there should be reciprocal hyper links in those other documents. These features would speed research on critical issues and save staff time. A master plan and a pilot version were both developed in this first phase of the ERL.

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The aim was to investigate the efficacy of neoadjuvant docetaxel-cisplatin and identify prognostic factors for outcome in locally advanced stage IIIA (pN2 by mediastinoscopy) non-small-cell lung cancer (NSCLC) patients. In all, 75 patients (from 90 enrolled) underwent tumour resection after three 3-week cycles of docetaxel 85 mg m-2 (day 1) plus cisplatin 40 or 50 mg m-2 (days 1 and 2). Therapy was well tolerated (overall grade 3 toxicity occurred in 48% patients; no grade 4 nonhaematological toxicity was reported), with no observed late toxicities. Median overall survival (OS) and event-free survival (EFS) times were 35 and 15 months, respectively, in the 75 patients who underwent surgery; corresponding figures for all 90 patients enrolled were 28 and 12 months. At 3 years after initiating trial therapy, 27 out of 75 patients (36%) were alive and tumour free. At 5-year follow-up, 60 and 65% of patients had local relapse and distant metastases, respectively. The most common sites of distant metastases were the lung (24%) and brain (17%). Factors associated with OS, EFS and risk of local relapse and distant metastases were complete tumour resection and chemotherapy activity (clinical response, pathologic response, mediastinal downstaging). Neoadjuvant docetaxel-cisplatin was effective and tolerable in stage IIIA pN2 NSCLC, with chemotherapy contributing significantly to outcomes.

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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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PURPOSE: Recurrent head and neck cancer is associated to a poor survival prognosis. A high toxicity rate is demonstrated when surgery and/or radiotherapy and/or chemotherapy are combined. Furthermore, the duration of treatment is often not ethically compatible with the expected survival (median survival<1year). Normal tissues tolerance limits the use of reirradiation and stereotactic body radiotherapy (SBRT) could offer precise irradiation while sparing healthy tissues. After completion of a feasibility study, results of a multicentric study (Lille, Nancy & Nice) using SBRT with cetuximab are reported. The aim of the study was to deliver non toxic short course SBRT (2weeks) in order to get the same local control as the one demonstrated with longer protocols. METHODS AND MATERIALS: Patients with inoperable recurrent, or new primary tumor in a previously irradiated area, were included (WHO<3). Reirradiation (RT) dose was 36Gy in six fractions of 6Gy to the 85% isodose line covering 95% of the PTV with 5 injections of concomitant cetuximab (CT). All patients had previous radiotherapy, 85% had previous surgery and 48% previous chemotherapy. RESULTS: Between 11/2007 and 08/2010, 60 were included (46 men and 14 women), 56 received CT+RT, 3 were not treated and 1 received only CT. Median age was 60 (42-87)) and all 56 patients had squamous carcinoma and received concomitant cetuximab. Mean time between previous radiotherapy and the start of SBRT was 38months. Cutaneous toxicity was observed for 41 patients. There was one toxic death from hemorrhage and denutrition. Median follow-up was 11.4months. At 3months, response rate was 58.4% (95% CI: 43.2-72.4%) and disease control rate was 91.7% (95% CI: 80.0-97.7%). The one-year OS rate was 47.5% (95% CI: 30.8-62.4). CONCLUSION: These results suggest that short SBRT with cetuximab is an effective salvage treatment with good response rate in this poor prognosis population with previously irradiated HNC. Treatment is feasible and, with appropriate care to limiting critical structure, acute toxicities are acceptable. This combination may be the reference treatment is this population.

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Access management involves balancing the dual roles that roadways must play - through travel and access to property and economic activity. When these roles are not in proper balance, the result is a roadway system that functions sub-optimally. Arterial routes that have a too high driveway density and provide overly extensive access to property have high crash rates and begin to suffer in terms of traffic operations. Such routes become congested, delays increase, and mean travel speeds decline. The Iowa access management research and awareness project has had four distinct phases. Phase I involved a detailed review of the extensive national access management literature so lessons learned elsewhere could be applied in Iowa. In Phase II original case study research was conducted in Iowa. Phase III of the project concentrated on outreach and education about access management. Phase IV of the Iowa access management project extended the work conducted during Phases II and III. The main work products for Phase IV were as follows: 1) three additional before and after case studies, illustrating the impacts of various access management treatments on traffic safety, traffic operations, and business vitality; 2) an access management handbook aimed primarily at local governments in Iowa; 3) a modular access management toolkit with brief descriptions of various access management treatments and considerations; and 4) an extensive outreach plan aimed at getting the results of Phases I through IV of the project out to diverse audiences in Iowa and elsewhere.

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In this paper we propose a method for computing JPEG quantization matrices for a given mean square error or PSNR. Then, we employ our method to compute JPEG standard progressive operation mode definition scripts using a quantization approach. Therefore, it is no longer necessary to use a trial and error procedure to obtain a desired PSNR and/or definition script, reducing cost. Firstly, we establish a relationship between a Laplacian source and its uniform quantization error. We apply this model to the coefficients obtained in the discrete cosine transform stage of the JPEG standard. Then, an image may be compressed using the JPEG standard under a global MSE (or PSNR) constraint and a set of local constraints determined by the JPEG standard and visual criteria. Secondly, we study the JPEG standard progressive operation mode from a quantization based approach. A relationship between the measured image quality at a given stage of the coding process and a quantization matrix is found. Thus, the definition script construction problem can be reduced to a quantization problem. Simulations show that our method generates better quantization matrices than the classical method based on scaling the JPEG default quantization matrix. The estimation of PSNR has usually an error smaller than 1 dB. This figure decreases for high PSNR values. Definition scripts may be generated avoiding an excessive number of stages and removing small stages that do not contribute during the decoding process with a noticeable image quality improvement.

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The questions studied in this thesis are centered around the moment operators of a quantum observable, the latter being represented by a normalized positive operator measure. The moment operators of an observable are physically relevant, in the sense that these operators give, as averages, the moments of the outcome statistics for the measurement of the observable. The main questions under consideration in this work arise from the fact that, unlike a projection valued observable of the von Neumann formulation, a general positive operator measure cannot be characterized by its first moment operator. The possibility of characterizing certain observables by also involving higher moment operators is investigated and utilized in three different cases: a characterization of projection valued measures among all the observables is given, a quantization scheme for unbounded classical variables using translation covariant phase space operator measures is presented, and, finally, a mathematically rigorous description is obtained for the measurements of rotated quadratures and phase space observables via the high amplitude limit in the balanced homodyne and eight-port homodyne detectors, respectively. In addition, the structure of the covariant phase space operator measures, which is essential for the above quantization, is analyzed in detail in the context of a (not necessarily unimodular) locally compact group as the phase space.

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Thereis now growing evidencethatthe hippocampus generatestheta rhythmsthat can phase biasfast neural oscillationsinthe neocortex, allowing coordination of widespread fast oscillatory populations outside limbic areas. A recent magnetoencephalographic study showed that maintenance of configural-relational scene information in a delayed match-to-sample (DMS) task was associated with replay of that information during the delay period. The periodicity of the replay was coordinated by the phase of the ongoing theta rhythm, and the degree of theta coordination during the delay period was positively correlated with DMS performance. Here, we reanalyzed these data to investigate which brain regions were involved in generating the theta oscillations that coordinated the periodic replay of configural- relational information. We used a beamformer algorithm to produce estimates of regional theta rhythms and constructed volumetric images of the phase-locking between the local theta cycle and the instances of replay (in the 13- 80 Hz band). We found that individual differences in DMS performancefor configural-relational associations were relatedtothe degree of phase coupling of instances of cortical reactivations to theta oscillations generated in the right posterior hippocampus and the right inferior frontal gyrus. This demonstrates that the timing of memory reactivations in humans is biased toward hippocampal theta phase

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BACKGROUND: One of the standard options in the treatment of stage IIIA/N2 non-small-cell lung cancer is neoadjuvant chemotherapy and surgery. We did a randomised trial to investigate whether the addition of neoadjuvant radiotherapy improves outcomes. METHODS: We enrolled patients in 23 centres in Switzerland, Germany and Serbia. Eligible patients had pathologically proven, stage IIIA/N2 non-small-cell lung cancer and were randomly assigned to treatment groups in a 1:1 ratio. Those in the chemoradiotherapy group received three cycles of neoadjuvant chemotherapy (100 mg/m(2) cisplatin and 85 mg/m(2) docetaxel) followed by radiotherapy with 44 Gy in 22 fractions over 3 weeks, and those in the control group received neoadjuvant chemotherapy alone. All patients were scheduled to undergo surgery. Randomisation was stratified by centre, mediastinal bulk (less than 5 cm vs 5 cm or more), and weight loss (5% or more vs less than 5% in the previous 6 months). The primary endpoint was event-free survival. Analyses were done by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00030771. FINDINGS: From 2001 to 2012, 232 patients were enrolled, of whom 117 were allocated to the chemoradiotherapy group and 115 to the chemotherapy group. Median event-free survival was similar in the two groups at 12·8 months (95% CI 9·7-22·9) in the chemoradiotherapy group and 11·6 months (8·4-15·2) in the chemotherapy group (p=0·67). Median overall survival was 37·1 months (95% CI 22·6-50·0) with radiotherapy, compared with 26·2 months (19·9-52·1) in the control group. Chemotherapy-related toxic effects were reported in most patients, but 91% of patients completed three cycles of chemotherapy. Radiotherapy-induced grade 3 dysphagia was seen in seven (7%) patients. Three patients died in the control group within 30 days after surgery. INTERPRETATION: Radiotherapy did not add any benefit to induction chemotherapy followed by surgery. We suggest that one definitive local treatment modality combined with neoadjuvant chemotherapy is adequate to treat resectable stage IIIA/N2 non-small-cell lung cancer. FUNDING: Swiss State Secretariat for Education, Research and Innovation (SERI), Swiss Cancer League, and Sanofi.

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Aim: We have previously documented the feasibility of neoadjuvant chemotherapy and EPP in a multicenter trial of MPM (Weder, Ann Oncol 18: 1196, 2007). The objectives of the trimodality trial SAKK17/04 (NCT00334594) were to evaluate the time to loco-regional relapse with or without high dose hemithoracic radiotherapy in a prospective multicenter randomized phase II trial in patients with R0 and R1 resection after neoadjuvant chemotherapy and EPP. Methods: Eligible patients had pathologically confirmed MPM, surgically resectable TNM stage (T1-3 N0-2 M0), PS0-1, ages 18-70 years. Part 1 had a phase II design, and included neoadjuvant chemotherapy with 3 cycles of cisplatin and pemetrexed, followed by restaging and EPP. The primary endpoint of part 1 was complete macroscopic resection (R0-1). Part 2 randomized consenting patients with R0-1 resection into two parallel phase II arms (control arm A and radiotherapy arm B). The primary endpoint for part 2 was loco-regional relapse-free survival (RFS). To detect a 1 year increase with 80% power and 10% alpha, 37 patients were needed for arm B. Secondary endpoints included operability, tolerability of chemotherapy and radiotherapy, survival, and translational research Results: Because accrual of part 2 was slower than planned, the trial was stopped in 2013. Overall, 153 patients entered the trial, of whom 125 underwent surgery and 99 had a complete macroscopic resection (primary endpoint part 1). Of the later patients, 54 could be randomized 1:1 into each arm. Reasons for non-randomization included patient refusal in 24 and ineligibility or protocol deviations in 21. Of the 27 patients randomized to hemithoracic radiotherapy, 25 completed the treatment as planned. For part 1 the median RFS was 8.8 (95%CI: 7.3-10.7) and median OS was 15.0 (95% CI: 12.1-19.3) months. For part 2 the median local RFS for group A was 7.6 (95%CI: 5.5-10.7) and for group B 9.4 (95%CI: 6.5-11.9) months (primary endpoint part 2), while the overall RFS and OS for group A were 5.7 (95%CI: 3.5-8.8) and 16.9 (95%CI: 10.7-23.6) months and for group B 7.6 (95% CI:5.2-10.6) and 14.9 (95%CI: 7.0-17.6) months. Conclusions: This study did not reach the primary endpoint which was defined as one-year increase in loco-regional relapse-free survival and thus does not support the routine use of hemithoracic RT after neoadjuvant chemotherapy and EPP. Disclosure: All authors have declared no conflicts of interest.

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Aim: One standard option in the treatment of stage IIIA/N2 NSCLC is neoadjuvant chemotherapy followed by surgery. We investigated in a randomized trial whether the addition of neoadjuvant radiotherapy would improve the outcome. Here we present the final results of this study. Methods: Patients (pts.) with pathologically proven, resectable stage IIIA/N2 NSCLC, performance status 0-1, and adequate organ function were randomized 1:1 to chemoradiation (CRT) with 3 cycles of neoadjuvant chemotherapy (cisplatin 100 mg/m2 and docetaxel 85 mg/m2 d1, q3weeks) followed by accelerated concomitant boost radiotherapy (RT) with 44 Gy in 22 fractions in 3 weeks, or neoadjuvant chemotherapy alone (CT), with subsequent surgery for all pts. The primary endpoint was event-free survival (EFS). Results: 232 pts. were randomized in 23 centers, the median follow-up was 53 months. Two thirds were men, median age was 60 years (range 37-76). Histology was squamous cell in 33%, adenocarcinoma in 43%. Response rate to CRT was 61% vs. 44% with CT. 85% of all pts. underwent surgery, 30-day postoperative mortality was 1%. The rate of complete resection was 91% (CRT) vs. 81% (CT) and the pathological complete remission (pCR) rate was 16% vs. 12%. The median EFS was 13.1 months (95% CI 9.9 - 23.5) for the CRT group vs. 11.8 months (95% CI 8.4 - 15.2) in the CT arm (p 0.665). The median overall survival (OS) with CRT was 37.1 months (95% CI 22.6 -50), with CT 26.1 months ( 95% CI 26.1 - 52.1, p 0.938). The local failure rate was 23% in both arms. In the CT arm 12 pts. were given postoperative radiotherapy (PORT) for R1 resection, 6 pts. received PORT in violation of the protocol. Pts. with a pCR, mediastinal downstaging to ypN0/1 and complete resection had a better outcome. Toxicity of chemotherapy was substantial, especially febrile neutropenia was common, whereas RT was well tolerated. Conclusions: This is the first completed phase III trial to evaluate the role of induction chemoradiotherapy and surgery, in comparison to neoadjuvant CT alone followed by surgery. RT was active, it increased response, complete resection and pCR rates. However, this failed to translate into an improvement of local control, EFS or OS. Notably, surgery after induction treatment was safe, including pneumonectomy. The overall survival rates of our neoadjuvant regimen are very encouraging, especially for a multicenter setting. Disclosure: M. Pless: Advisory Board for Sanofi; R. Cathomas: Advisory Board Sanofi D.C. Betticher: Advisory Board Sanofi. All other authors have declared no conflicts of interest.