Criteria For Stopping Research Articles

Some unusual results on extrapolation methods

This paper is devoted to properties of sequence transformations and the corresponding recursive algorithms for their implementation, which were never considered before. We first give necessary conditions that are satisfied if the transformed sequence converges faster than the initial one. These conditions can be used for deciding if a method is worth to be used. They also serve as the basis for defining criteria for stopping the acceleration algorithm when the best possible precision is obtained. Then, prescribing the transformed sequence, we show how to obtain the initial sequence which produces it via the transformation or via its recursive algorithm. These results show that almost any behavior is possible for the transformed sequence. A similar problem about Pade-type approximants is studied.

Estimation of a ground motion model for induced events by Fahlman's Cascade Correlation Neural Network

In this paper, a ground motion model (GMM) estimation by Fahlman's Cascade Correlation Neural Network is proposed. We start with a linearised regression estimator and improve the GMM for the Legnica-Głogów Copper District in Poland by adding levels with nonlinear neurons. This gradually leads to the creation of a deep Artificial Neural Network GMM. The paper focuses on the selection of criteria for stopping the development of the network, including minimising the prediction risk, which is defined as the estimation of the quality of the GMM in future observations. Therefore, the solution presented here only applies to the simplest case, which considers only magnitude and distance.

МНОГОФУНКЦИОНАЛЬНАЯ ОПТИМИЗАЦИЯ ПРИ КОМПЕНСАЦИИ РЕАКТИВНОЙ МОЩНОСТИ

Актуальность. В настоящее время в России создается интеллектуальная энергосистема с активно­-адаптивной сетью – ИЭС ААС (за рубежом – Smart Grid). Базовым кластером архитектуры Smart Grid являются FACTS-устройства, сложность проектирования которых заключается в многокритериальности задачи. Оптимизация реактивной мощности представляет собой подзадачу оптимального потока мощности, в ходе решения которой определяется правильная настройка переменных реактивной мощности, таких как величины: напряжения, положений ступеней трансформаторов и характеристик устройств компенсации реактивной мощности. Решение задач оптимизации реактивной мощности, которые не являются линейными и дискретными, при использовании традиционных методов оптимизации сопровождается определенными трудностями, связанными с обработкой данных разного характера. Поэтому в настоящее время ведется поиск адекватного способа многообъектной обработки данных, например, с помощью алгоритма эволюционной оптимизации. Целью исследования является разработка математического метода поиска оптимального решения из всего множества возможных решений, которое было бы лучше других хотя бы для одной из поставленных целей. При этом модель должна выполнять расчет потока мощности на основной и гармонической частоте для конкретного режима, при большом количестве ограничений. Методы. Моделирование для внедрения устройств FACTS было выполнено в программе DYCSE. Использовался алгоритм случайного поиска, который является модификацией метода интеграции переменных. Он позволяет решать проблемы сходимости при применении к очень большому массиву данных. В качестве примера и основы для разработки обсуждаемого метода был принят метод расчета и результаты исследования Jos? Arzola Ruiz. В данном исследовании оптимизации используется целевая функция метода Чебышева, позволяющая уменьшить взвешенное расстояние от расчетного до желаемого значения каждого индикатора, включенного в целевую функцию. Естественно, что популяция с высоким уровнем исходных данных представляет лучшее решение задачи и при определенных условиях может представлять даже единственно оптимальное решение. Из первоначального поколения потенциальных решений для процесса, который является повторяющимся, вычислялись новые поколения решений, каждый раз с лучшими характеристиками, наиболее близкими к оптимальному решению задачи. Критерии остановки расчета представляли собой смешанное условие – разницу между худшим и лучшим решениями. Каждый эксперимент выполнялся с начальной популяцией, которая имела случайный характер. Исследования показали, что при заданном диапазоне изменения любого параметра, применяемого для решения поставленной задачи компенсации реактивной мощности в электрических сетях, достаточно количество сочетаний ограничить 7 % от всех возможных его значений. В результате реализации алгоритма получается множество решений с минимальными значениями целевой функции. В ходе расчета задача эксперта заключается в выборе рабочего варианта. Результаты. Применение эволюционных методов в оптимизации позволяет одновременно рассматривать несколько независимых решений, создавая набор так называемых оптимально эффективных решений, или решений Pareto, которые удовлетворяют целям исследования. Во всех экспериментах были получены эффективные решения при оценке численности популяции около 10 % от всех возможных решений. Полученные решения можно считать эффективными в сравнении с расчетами, которые можно было бы произвести при наличии абсолютно всех необходимых исходных данных и выполненных полномасштабных вычислений. Выводы. Для достижения энергоэффективности в промышленных сетях требуются новые методы оптимизации, позволяющие улучшить технико-экономические показатели сетей. Использование метода Чебышева позволяет уменьшить взвешенное расстояние от расчетного до желаемого значения каждого индикатора, включенного в целевую функцию. Теоретические расчеты прошли апробацию в ходе практических исследований. Доказано, что для значений, близких к 10 % от спектра всех возможных решений, можно получить решения, которые удовлетворяют требованиям поиска эффективных решений. Разработанный алгоритм значительно сокращает время вычислений при гарантии сходимости результатов и совпадает с рекомендациями, предложенными Arzola.

Autologous Blood Patch Injection versus Hydrogel Plug in CT-guided Lung Biopsy: A Prospective Randomized Trial.

Purpose To compare the effect of autologous blood patch injection (ABPI) with that of a hydrogel plug on the rate of pneumothorax at CT-guided percutaneous lung biopsy. Materials and Methods In this prospective randomized controlled trial ( https://ClinicalTrials.gov , NCT02224924), a noninferiority design was used for ABPI, with a 10% noninferiority margin when compared with the hydrogel plug, with the primary outcome of pneumothorax rate within 2 hours of biopsy. A type I error rate of 0.05 and 90% power were specified with a target study population of 552 participants (276 in each arm). From October 2014 to February 2017, all potential study participants referred for CT-guided lung biopsy (n = 2052) were assessed for enrollment. Results The data safety monitoring board recommended the trial be closed to accrual after an interim analysis met prespecified criteria for early stopping based on noninferiority. The final study group consisted of 453 participants who were randomly assigned to the ABPI (n = 226) or hydrogel plug (n = 227) arms. Of these, 407 underwent lung biopsy. Pneumothorax rates within 2 hours of biopsy were 21% (42 of 199) and 29% (60 of 208); chest tube rates were 9% (18 of 199) and 13% (27 of 208); and delayed pneumothorax rates within 2 weeks after biopsy were 1.4% (three of 199) and 1.5% (three of 208) in the ABPI and hydrogel plug arms, respectively. Conclusion Autologous blood patch injection is noninferior to a hydrogel plug regarding the rate of pneumothorax after CT-guided percutaneous lung biopsy. © RSNA, 2018 Online supplemental material is available for this article.

Variable criteria sequential stopping rule: Validity and power with repeated measures ANOVA, multiple correlation, MANOVA and relation to Chi-square distribution.

The variable criteria sequential stopping rule (vcSSR) is an efficient way to add sample size to planned ANOVA tests while holding the observed rate of Type I errors, αo, constant. The only difference from regular null hypothesis testing is that criteria for stopping the experiment are obtained from a table based on the desired power, rate of Type I errors, and beginning sample size. The vcSSR was developed using between-subjects ANOVAs, but it should work with p values from any type of F test. In the present study, the αo remained constant at the nominal level when using the previously published table of criteria with repeated measures designs with various numbers of treatments per subject, Type I error rates, values of ρ, and four different sample size models. New power curves allow researchers to select the optimal sample size model for a repeated measures experiment. The criteria held αo constant either when used with a multiple correlation that varied the sample size model and the number of predictor variables, or when used with MANOVA with multiple groups and two levels of a within-subject variable at various levels of ρ. Although not recommended for use with χ2 tests such as the Friedman rank ANOVA test, the vcSSR produces predictable results based on the relation between F and χ2. Together, the data confirm the view that the vcSSR can be used to control Type I errors during sequential sampling with any t- or F-statistic rather than being restricted to certain ANOVA designs.

Reservoir Simulator Runtime Enhancement Based ona PosterioriError Estimation Techniques

In this work, we show how the a posteriori error estimation techniques proposed in [Di Pietro et al. (2014) Computers & Mathematics with Applications 68 , 2331-2347] can be efficiently employed to improve the performance of a compositional reservoir simulator dedicated to Enhanced Oil Recovery (EOR) processes. This a posteriori error estimate allows to propose an adaptive mesh refinement algorithm leading to significant gain in terms of the number of cells in mesh compared to a fine mesh resolution, and to formulate criteria for stopping the iterative algebraic solver and the iterative linearization solver without any loss of precision. The emphasis of this paper is on the computational cost of the error estimators. We introduce an efficient computation using a practical simplified formula that can be easily implemented in a reservoir simulation code. Numerical results for a real-life reservoir engineering example in three dimensions show that we obtain a significant gain in CPU times without affecting the accuracy of the oil production forecast.

Optimize heat conduction problem using level set method with a weighting based velocity constructing scheme

This paper is devoted to develop an efficient computational procedure for the level set-based topological design of heat conducting fields. Firstly, the level set model with a distance-suppression scheme (generalized Hamilton–Jacobi equation) is used to implicitly represent boundary of heat conductive material so that the periodical re-initialization can be avoided. Secondly, after demonstrating that the finite element thermal analysis takes the major portion of the total computational time, we present a weighting based velocity constructing method inspired from the conjugate gradient method to avoid performing finite element thermal analysis for solving the generalized Hamilton–Jacobi equation. Thirdly, a velocity renewing procedure and criteria for stopping the weighting method are developed for insuring the stability and a quick convergence. Finally, two dimensional topology optimization results of heat conduction problem under both single and multiple load cases are presented to demonstrate the validity of the proposed method.

A randomised controlled trial to assess the clinical effectiveness and cost-effectiveness of alternative treatments to Inhibit VEGF in Age-related choroidal Neovascularisation (IVAN).

Bevacizumab (Avastin®, Roche), which is used in cancer therapy, is the 'parent' molecule from which ranibizumab (Lucentis®, Novartis) was derived for the treatment of neovascular age-related macular degeneration (nAMD). There were reports in the literature on the effectiveness of bevacizumab in treating nAMD, but no trials. The cost per dose of bevacizumab is about 5-10% that of ranibizumab. This trial was a head-to-head comparison of these two drugs. To compare the clinical effectiveness and cost-effectiveness of ranibizumab and bevacizumab, and two treatment regimens, for nAMD. Multicentre, factorial randomised controlled trial with within-trial cost-utility and cost-minimisation analyses from the perspective of the UK NHS. Participants, health professionals and researchers were masked to allocation of drug but not regimen. Computer-generated random allocations to combinations of ranibizumab or bevacizumab, and continuous or discontinuous regimen, were stratified by centre, blocked and concealed. Twenty-three ophthalmology departments in NHS hospitals. Patients ≥ 50 years old with active nAMD in the study eye with best corrected distance visual acuity (BCVA) ≥ 25 letters measured on a Early Treatment of Diabetic Retinopathy Study (ETDRS) chart. Previous treatment for nAMD, long-standing disease, lesion diameter > 6000 µm, thick blood at the fovea and any other confounding ocular disease were exclusion criteria. One eye per participant was studied; the fellow eye was treated according to usual care, if required. Ranibizumab and bevacizumab were procured commercially. Doses were ranibizumab 0.5 mg or bevacizumab 1.25 mg. The repackaged bevacizumab was quality assured. All participants were treated at visits 0, 1 and 2. Participants randomised to the continuous regimen were treated monthly thereafter. Participants randomised to the discontinuous regimen were not retreated after visit 2 unless pre-specified criteria for active disease were met. If retreatment was needed, monthly injections over 3 months were mandated. The primary outcome was BCVA. The non-inferiority margin was 3.5 letters. Secondary outcomes were contrast sensitivity; near visual acuity; reading index; neovascular lesion morphology; generic and disease-specific patient-reported outcomes, including macular disease-specific quality of life; survival free from treatment failure; resource use; quality-adjusted life-years (QALYs); and development of new geographic atrophy (GA) (outcome added during the trial). Results are reported for the study eye, except for patient-reported outcomes. Between 27 March 2008 and 15 October 2010, 610 participants were allocated and treated (314 ranibizumab, 296 bevacizumab; at 3 months, 305 continuous, 300 discontinuous). After 2 years, bevacizumab was neither non-inferior nor inferior to ranibizumab [-1.37 letters, 95% confidence interval (CI) -3.75 to +1.01 letters] and discontinuous treatment was neither non-inferior nor inferior to continuous treatment (-1.63 letters, 95% CI -4.01 to +0.75 letters). Lesion thickness at the fovea was similar by drug [geometric mean ratio (GMR) 0.96, 95% CI 0.90 to 1.03; p = 0.24] but 9% less with continuous treatment (GMR 0.91, 95% CI 0.85 to 0.97; p = 0.004). Odds of developing new GA during the trial were similar by drug [odds ratio (OR) 0.87, 95% CI 0.61 to 1.25; p = 0.46] but significantly higher with continuous treatment (OR 1.47, 95% CI 1.03 to 2.11; p = 0.033). Safety outcomes did not differ by drug but mortality was lower with continuous treatment (OR 0.47, 95% CI 0.22 to 1.03; p = 0.05). Continuous ranibizumab cost £3.5M per QALY compared with continuous bevacizumab; continuous bevacizumab cost £30,220 per QALY compared with discontinuous bevacizumab. These results were robust in sensitivity analyses. Ranibizumab and bevacizumab have similar efficacy. Discontinuing treatment and restarting when required results in slightly worse efficacy. Safety was worse with discontinuous treatment, although new GA developed more often with continuous treatment. Ranibizumab is not cost-effective, although it remains uncertain whether or not continuous bevacizumab is cost-effective compared with discontinuous bevacizumab at £20,000 per QALY threshold. Future studies should focus on the ocular safety of the two drugs, further optimisation of treatment regimens and criteria for stopping treatment. Current Controlled Trials ISRCTN92166560. This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 19, No. 78. See the NIHR Journals Library website for further project information.

Choosing the optimal number of generations in the genetic algorithms with binary-real solutions coding

This work is devoted to the problem of choosing the optimal stopping criterion in the transition from the binary coding to the real number coding in genetic algorithms with binary-real representation of solutions in the chromosomes. The main criteria for stopping the modern genetic algorithms based on the phenotype or genotype of individuals are considered. Their advantages and disadvantages are presented. The main purpose of research is to develop a new intermediate stopping criterion of genetic algorithm with binary-real coding. The developed criteria based on the fact that the values of best chromosomes change within a certain low threshold for some generations. New intermediate stopping criterion allows the efficient spending computing resources using genetic algorithms with binary-real coding. A comparative efficiency analysis of the new stopping criterion of the transition from one type of coding to another in the optimization of complex multi-extremal function is conducted. Efficiency analysis allowed forming recommendations for the selection of the threshold values in the calculation of a new stopping criterion. The same analysis showed inefficient use of population convergence criterion as an intermediate stopping criterion. The advantages of the new criterion above the criteria based on the fact that the value of the best chromosomes is constantly for several generations are presented.

CORRELATION OF ARTIFICIAL NEURAL NETWORK CLASSIFICATION AND NFRS ATTRIBUTE FILTERING ALGORITHM FOR PCOS DATA

Mostly 5 to 15% of the women in the stage of reproduction face the disease called Polycystic Ovarian Syndrome (PCOS) which is the multifaceted, heterogeneous and complex. The long term consequences diseases like endometrial hyperplasia, type 2 diabetes mellitus and coronary disease are caused by the polycystic ovaries, chronic anovulation and hyperandrogenism are characterized with the resistance of insulin and the hypertension, abdominal obesity and dyslipidemia and hyperinsulinemia are called as Metabolic syndrome (frequent metabolic traits) The above cause the common disease called Anovulatory infertility. Computer based information along with advanced Data mining techniques are used for appropriate results. Classification is a classic data mining task, with roots in machine learning. Naive Bayesian, Artificial Neural Network, Decision Tree, Support Vector Machines are the classification tasks in the data mining. Feature selection methods involve generation of the subset, evaluation of each subset, criteria for stopping the search and validation procedures. The characteristics of the search method used are important with respect to the time efficiency of the feature selection methods. PCA (Principle Component Analysis), Information gain Subset Evaluation, Fuzzy rough set evaluation, Correlation based Feature Selection (CFS) are some of the feature selection techniques, greedy first search, ranker etc are the search algorithms that are used in the feature selection. In this paper, a new algorithm which is based on Fuzzy neural subset evaluation and artificial neural network is proposed which reduces the task of classification and feature selection separately. This algorithm combines the neural fuzzy rough subset evaluation and artificial neural network together for the better performance than doing the tasks separately.

Under-reporting and Poor Adherence to Monitoring Guidelines for Severe Cases of Isoniazid Hepatotoxicity

Isoniazid is a leading cause of liver injury but it is not clear how many cases are reported or how many clinicians and patients adhere to American Thoracic Society (ATS) guidelines. We collected data on cases of isoniazid hepatotoxicity and assessed adherence to ATS guidelines and reports to the Centers for Disease Control's (CDC) isoniazid severe adverse events program. We analyzed Drug-Induced Liver Injury Network (DILIN) cases considered definite, highly likely, or probable for isoniazid injury from 2004 through 2013. We assessed the delays in isoniazid discontinuance according to ATS criteria and hepatotoxicity severity by Severity Index Score. We checked reporting to the CDC by matching cases based on age, latency, indication, reporting period, and comorbidities. Isoniazid was the second most commonly reported agent in the DILIN, with 69 cases; 60 of these met inclusion criteria. The median age of cases was 49 years (range, 4-68 y), 70% were female, 97% had latent tuberculosis, and 62% were hospitalized. Patients took a median of 9 days to stop taking isoniazid (range, 0-99 days). Thirty-three cases (55%) continued taking isoniazid for more than 7 days after the ATS criteria for stopping were met. Twenty-four cases (40%) continued isoniazid for more than 14 days after meeting criteria for stopping. A delay in stopping was associated with more severe injury (P < .05). Of 13 patients who died or underwent liver transplantation, 9 (70%) continued taking isoniazid for more than 7 days after meeting criteria for stopping. Only 1 of 25 cases of isoniazid hepatotoxicity eligible for reporting to the CDC was reported. Poor adherence to ATS guidelines is common in cases of hepatotoxicity and is associated with more severe outcomes including hospitalization, death, and liver transplantation. Isoniazid continues to be a leading cause of DILI in the United States, and its hepatotoxicity is under-reported significantly.

Osteonecrosis of the Jaw After Bisphosphonates Treatment in Patients with Multiple Myeloma.

Background:Bone lytic lesion in Multiple myeloma are the most commonly presented symptoms which require treatment with bisphosphonates (BPs). BPs are providing supportive care, reducing the rate of skeletal morbidity but evidently not abolishing it, the criteria for stopping their administration have to be different from those used for classic antineoplastic drugs, and they should not be stopped when metastatic bone disease is progressing. Osteonecrosis of the jaw (ONJ) has been associated recently with the use of BPs.Aim:The aim of these study is to evaluate the incidence of ONJ in patients with MM treated with mixed biphosphonates.Patients and methods:We analyzed total 296 myeloma patients (150 male and 146 female). Mostly effected age group with 58,1% is age more than 60 years up to 88 years, diagnosed in our institution in the period 2005-2015. We used intravenous or oral forms of biphosphonates such as pamidronate, ibandronate, clodronate and zolendronic acid. The patients were evaluated for ONJ.Results:The incidence of ONJ in our group of patients treated with Bps was 4,6% from our group of 260 patients 87,8% received BPs therapy and patients which haven’t received BPs 12,2%. From this group, 95,4% (248) didn’t show ONJ, and 4,6% (12) showed ONJ. The period of this treatment with BPs is an important risk factor for development of ONJ, average duration of BPs therapy in patients which show adverse effects is 26.8±13.7 months, from the total number of 12 patients that developed ONJ adverse effects, we have 8 patients which received treatment with Zolendronic acid and the remaining 4 patients which were treated with other BPs combinations without Zolendronic acid.Conclusions:All patients treated for MM must continue with the therapy with Zolendronic acid and Pamidronate, each patient must be individually treated according to his response of the treatment (dose, frequency and duration of therapy).

A posteriori error estimates, stopping criteria, and adaptivity for multiphase compositional Darcy flows in porous media

In this paper we derive a posteriori error estimates for the compositional model of multiphase Darcy flow in porous media, consisting of a system of strongly coupled nonlinear unsteady partial differential and algebraic equations. We show how to control the dual norm of the residual augmented by a nonconformity evaluation term by fully computable estimators. We then decompose the estimators into the space, time, linearization, and algebraic error components. This allows to formulate criteria for stopping the iterative algebraic solver and the iterative linearization solver when the corresponding error components do not affect significantly the overall error. Moreover, the spatial and temporal error components can be balanced by time step and space mesh adaptation. Our analysis applies to a broad class of standard numerical methods, and is independent of the linearization and of the iterative algebraic solvers employed. We exemplify it for the two-point finite volume method with fully implicit Euler time stepping, the Newton linearization, and the GMRes algebraic solver. Numerical results on two real-life reservoir engineering examples confirm that significant computational gains can be achieved thanks to our adaptive stopping criteria, already on fixed meshes, without any noticeable loss of precision.

COMPARING DIFFERENT STOPPING CRITERIA FOR FUZZY DECISION TREE INDUCTION THROUGH IDFID3

Fuzzy Decision Tree (FDT) classifiers combine decision trees with approximate reasoning offered by fuzzy representation to deal with language and measurement uncertainties. When a FDT induction algorithm utilizes stopping criteria for early stopping of the tree's growth, threshold values of stopping criteria will control the number of nodes. Finding a proper threshold value for a stopping criterion is one of the greatest challenges to be faced in FDT induction. In this paper, we propose a new method named Iterative Deepening Fuzzy ID3 (IDFID3) for FDT induction that has the ability of controlling the tree’s growth via dynamically setting the threshold value of stopping criterion in an iterative procedure. The final FDT induced by IDFID3 and the one obtained by common FID3 are the same when the numbers of nodes of induced FDTs are equal, but our main intention for introducing IDFID3 is the comparison of different stopping criteria through this algorithm. Therefore, a new stopping criterion named Normalized Maximum fuzzy information Gain multiplied by Number of Instances (NMGNI) is proposed and IDFID3 is used for comparing it against the other stopping criteria. Generally speaking, this paper presents a method to compare different stopping criteria independent of their threshold values utilizing IDFID3. The comparison results show that FDTs induced by the proposed stopping criterion in most situations are superior to the others and number of instances stopping criterion performs better than fuzzy information gain stopping criterion in terms of complexity (i.e. number of nodes) and classification accuracy. Also, both tree depth and fuzzy information gain stopping criteria, outperform fuzzy entropy, accuracy and number of instances in terms of mean depth of generated FDTs.

Compressive Strength of Confined Concrete in CCFST Columns

Article history: Received: 17 August 2012 Accepted: 19 May 2013 This paper presents a new model for predicting the compressive strength of steel-confined concrete on circular concrete filled steel tube (CCFST) stub columns under axial loading condition based on Artificial Neural Networks (ANNs) using a wide range of experimental investigations. Based on the previous theoretical and experimental studies the input variables considered in developing the ANNs model are outer diameter of column, compressive strength of unconfined concrete, length of column, wall thickness and tensile yield stress of steel tube. After the learning step, the neural network can be extracted the relationships between the input variables and output parameter. The criteria for stopping the training of the networks are Regression values and Mean Square Error. After constructing networks with constant input neurons but with different number of hiddenlayer neurons, the best network was selected. The neural network results are compared with the existing models which showed the results are in good agreement with experiments.

Level Set Segmentation of Breast Masses in Contrast-Enhanced Dedicated Breast CT and Evaluation of Stopping Criteria

Dedicated breast CT (bCT) produces high-resolution 3D tomographic images of the breast, fully resolving fibroglandular tissue structures within the breast and allowing for breast lesion detection and assessment in 3D. In order to enable quantitative analysis, such as volumetrics, automated lesion segmentation on bCT is highly desirable. In addition, accurate output from CAD (computer-aided detection/diagnosis) methods depends on sufficient segmentation of lesions. Thus, in this study, we present a 3D lesion segmentation method for breast masses in contrast-enhanced bCT images. The segmentation algorithm follows a two-step approach. First, 3D radial-gradient index segmentation is used to obtain a crude initial contour, which is then refined by a 3D level set-based active contour algorithm. The data set included contrast-enhanced bCT images from 33 patients containing 38 masses (25 malignant, 13 benign). The mass centers served as input to the algorithm. In this study, three criteria for stopping the contour evolution were compared, based on (1) the change of region volume, (2) the average intensity in the segmented region increase at each iteration, and (3) the rate of change of the average intensity inside and outside the segmented region. Lesion segmentation was evaluated by computing the overlap ratio between computer segmentations and manually drawn lesion outlines. For each lesion, the overlap ratio was averaged across coronal, sagittal, and axial planes. The average overlap ratios for the three stopping criteria ranged from 0.66 to 0.68 (dice coefficient of 0.80 to 0.81), indicating that the proposed segmentation procedure is promising for use in quantitative dedicated bCT analyses.

Interim safety and efficacy analysis of a phase II, randomized study of GVAX pancreas and CRS-207 immunotherapy in patients with metastatic pancreatic cancer.

4040^ Background: GVAX is composed of GM-CSF-secreting allogeneic pancreas cancer cell lines and administered with low-dose cyclophosphamide (CY) to inhibit regulatory T cells. In prior studies, GVAX induced mesothelin-specific T cell responses that correlated with survival. CRS-207 is a live-attenuated Listeria monocytogenes engineered to express human mesothelin. CRS-207 stimulates potent innate and adaptive immunity and has shown synergy with GVAX in mouse tumor models. Anecdotal survival benefit was observed in the CRS-207 phase I study in patients who received prior GVAX. Methods: Patients were enrolled with metastatic pancreatic ductal adenocarcinoma (PDA) who received or refused ≥ 1 prior chemotherapy, had ECOG ≤ 1 and adequate organ function. Patients were randomized 2:1 to receive 2 doses of CY/GVAX followed by 4 doses of CRS-207 (Arm A) or 6 doses of CY/GVAX (Arm B) every 3 weeks. Clinically stable patients were offered additional 20-week courses. The primary endpoint was comparison of OS between treatment arms. Secondary endpoints were to evaluate safety, clinical and immune responses. Results: 90 patients were treated (Arm A: 61, Arm B: 29). As of Jan 2013, 27 patients completed 1 course (A: 24, B: 3) and 17 patients (A: 15, B: 2) initiated a 2nd course. Median age was 63. Median number of prior regimens was 3. No treatment-related serious adverse events (SAEs) or unexpected toxicities were observed. The most frequent Grade (G) 3/4 related toxicities were fever, lymphopenia, hypophosphatemia, elevated liver enzymes, and fatigue following CRS-207 in &lt;5% of subjects. Of 51 patients evaluated post-treatment, 34% had stable disease in Arm A vs. 19% in Arm B. OS for all patients treated was 6 months in Arm A vs. 3.4 months in Arm B (two-sided, p=0.0114). Conclusions: Combined CY/GVAX pancreas and CRS-207 was generally well-tolerated with no treatment-related SAEs or unexpected G3/4 toxicities. The significant difference in OS between treatment arms met the criteria for early stopping. This indicates that the combination immunotherapy may extend OS for metastatic PDA patients with minimal toxicity and should continue to be developed as an effective therapy. Clinical trial information: NCT01417000.

1161 Quandry Over the Use of Antifungal Prophylaxis in Preterm Infants: Survey of Current Practice in the United Kingdom

IntroductionProphylactic anti fungal use reduces the incidence of colonisation and invasive fungal infection in premature neonates. We surveyed the current regimens for the use of antifungal prophylaxis in the tertiary...

Distribution of Feeding Styles after Pyloromyotomy among Pediatric Surgical Training Programs in North America

The feeding regimen employed after pyloromyotomy for pyloric stenosis continues to be a topic of debate and has yet to be evaluated in a prospective, randomized trial. To understand the spectrum of current feeding schedules being utilized in the various training programs, we queried the program directors or representatives about their feeding schedules. Through the use of multiple electronic communication resources, we surveyed 47 pediatric training programs in the United States and Canada about their postpyloromyotomy feeding schedules. Questions included time to first feed, how the schedule is advanced, and criteria for stopping feeds and discharge. Responses were received from 34 of the 47 institutions. Six programs had variable times of delay before instituting feeding whether ad libitum (ad lib) or protocol. The average time of delay was 4.3 hours. Six programs reported both ad lib feed and protocol feeding regiments. Twelve institutions used ad lib feeding regiments. Eight started feeding without delay. Twenty-six programs including our institution currently employ a protocol-based feeding regiment. Of these programs, seven begin the protocol without delay. Despite retrospective evidence in support of ad lib feeds after pyloromyotomy, the majority of teaching institutions employs protocols for the postpyloromyotomy feeding schedule. There is clearly a role for a prospective, randomized trial to compare ad lib to schedule feeding.

Distribution of Feeding Styles After Pyloromyotomy Among Pediatric Surgical Training Programs in North America

Introduction Thefeeding regimenemployedafter pyloromyotomy for pyloric stenosis continues to be a topic of debate and has yet to be evaluated in a prospective, randomized trial. To understand the spectrum of current feeding schedules being utilized in the various training programs, we queried the program directors or representatives about their feeding schedules. Methods Through the use of multiple electronic communication resources, we surveyed 47 pediatric training programs in the United States and Canada about their postpyloromyotomy feeding schedules. Questions included time to first feed, how the schedule is advanced, and criteria for stopping feeds and discharge. Results Reponses were received from 34 of the 47 institutions. Six programs had variable times ofdelay before instituting feeding whether ad libitum (ad lib) or protocol. The average time of delay was 4.3 hours. Six programs reported both ad lib feed and protocol feeding regiments. Twelve institutions used ad lib feeding regiments. Eight started feeding without delay. Twenty-six programs including our institution currently employ a protocol-based feeding regiment. Of these programs, seven begin the protocol without delay. Conclusions Despite retrospective evidence in support of ad lib feeds after pyloro- myotomy, the majority of teaching institutions employs protocols for the postpylor- omyotomy feeding schedule. There is clearly a role for a prospective, randomized trial to compare ad lib to schedule feeding.