scholarly journals A pareto ensemble based spectral clustering framework

2020 ◽  
Author(s):  
Juanjuan Luo ◽  
Huadong Ma ◽  
Dongqing Zhou
Keyword(s):  
Phase I ◽  
Phase Ii ◽  
Spectral Clustering ◽  
Clustering Algorithms ◽  
Divide And Conquer ◽  
Nonzero Entry ◽  
Similarity Matrix ◽  
Diversity Preservation ◽  
Two Phases ◽  
Matrix Construction

Abstract Similarity matrix has a significant effect on the performance of the spectral clustering, and how to determine the neighborhood in the similarity matrix effectively is one of its main difficulties. In this paper, a “divide and conquer” strategy is proposed to model the similarity matrix construction task by adopting Multiobjective evolutionary algorithm (MOEA). The whole procedure is divided into two phases, phase I aims to determine the nonzero entries of the similarity matrix, and Phase II aims to determine the value of the nonzero entries of the similarity matrix. In phase I, the main contribution is that we model the task as a biobjective dynamic optimization problem, which optimizes the diversity and the similarity at the same time. It makes each individual determine one nonzero entry for each sample, and the encoding length decreases to O(N) in contrast with the non-ensemble multiobjective spectral clustering. In addition, a specific initialization operator and diversity preservation strategy are proposed during this phase. In phase II, three ensemble strategies are designed to determine the value of the nonzero value of the similarity matrix. Furthermore, this Pareto ensemble framework is extended to semi-supervised clustering by transforming the semi-supervised information to constraints. In contrast with the previous multiobjective evolutionary-based spectral clustering algorithms, the proposed Pareto ensemble-based framework makes a balance between time cost and the clustering accuracy, which is demonstrated in the experiments section.

scholarly journals Spectral Clustering in Heterogeneous Information Networks

2019 ◽  
Vol 33 ◽  
pp. 4221-4228 ◽  
Author(s):  
Xiang Li ◽  
Ben Kao ◽  
Zhaochun Ren ◽  
Dawei Yin
Keyword(s):  
Spectral Clustering ◽  
Optimization Problem ◽  
Clustering Algorithms ◽  
Similarity Matrix ◽  
Heterogeneous Information ◽  
Heterogeneous Information Networks ◽  
Clustering Quality ◽  
Different Types ◽  
Meta Path ◽  
Matrix Construction

A heterogeneous information network (HIN) is one whose objects are of different types and links between objects could model different object relations. We study how spectral clustering can be effectively applied to HINs. In particular, we focus on how meta-path relations are used to construct an effective similarity matrix based on which spectral clustering is done. We formulate the similarity matrix construction as an optimization problem and propose the SClump algorithm for solving the problem. We conduct extensive experiments comparing SClump with other state-of-the-art clustering algorithms on HINs. Our results show that SClump outperforms the competitors over a range of datasets w.r.t. different clustering quality measures.

scholarly journals COVID-19 and radiation oncology: the experience of a two-phase plan within a single institution in central Italy

2020 ◽  
Vol 15 (1) ◽  
Author(s):  
Luciana Caravatta ◽  
Consuelo Rosa ◽  
Maria Bernadette Di Sciascio ◽  
Andrea Tavella Scaringi ◽  
Angelo Di Pilla ◽  
...  
Keyword(s):  
Phase I ◽  
Phase Ii ◽  
Central Italy ◽  
Significant Risk ◽  
Tumor Board ◽  
Radiotherapy Planning ◽  
Two Phase ◽  
Hospital Environments ◽  
Two Phases

Abstract Background COVID-19 in Italy has led to the need to reorganize hospital protocols with a significant risk of interruption to cancer treatment programs. In this report, we will focus on a management model covering the two phases of the COVID-19 emergency, namely lockdown-phase I and post-lockdown-phase II. Methods The following steps were taken in the two phases: workload during visits and radiotherapy planning, use of dedicated routes, measures for triage areas, management of suspected and positive COVID-19 cases, personal protective equipment, hospital environments and intra-institutional meetings and tumor board management. Due to the guidelines set out by the Ministry of Health, oncological follow-up visits were interrupted during the lockdown-phase I; consequently, we set about contacting patients by telephone, with laboratory and instrumental exams being viewed via telematics. During the post-lockdown-phase II, the oncological follow-up clinic reopened, with two shifts operating daily. Results By comparing our radiotherapy activity from March 9 to May 4 2019 with the same period in 2020 during full phase I of the COVID-19 emergency, similar results were achieved. First radiotherapy visits, Simulation Computed Tomography and Linear Accelerator treatments amounted to 123, 137 and 151 in 2019 compared with 121, 135 and 170 in 2020 respectively. There were no cases of COVID-19 positivity recorded either in patients or in healthcare professionals, who were all negative to the swab tests performed. Conclusion During both phases of the COVID-19 emergency, the planned model used in our own experience guaranteed both continuity in radiotherapy treatments whilst neither reducing workload nor interrupting treatment and, as such, it ensured the safety of cancer patients, hospital environments and staff.

scholarly journals Involvement of NO in Antinociception of NSAIDS in Murine Formalin Hind Paw Assay

Drug Research ◽  
2020 ◽  
Vol 70 (04) ◽  
pp. 145-150 ◽  
Author(s):  
Viviana Noriega ◽  
Hugo F. Miranda ◽  
Juan Carlos Prieto ◽  
Ramón Sotomayor-Zárate ◽  
Fernando Sierralta
Keyword(s):  
Phase I ◽  
Phase Ii ◽  
Dose Response ◽  
Rank Order ◽  
Linear Regression Analysis ◽  
Second Phase ◽  
Response Curves ◽  
Before And After ◽  
Two Phases ◽  
Phase Phase

AbstractThere are different animal models to evaluate pain among them the formalin hind paw assay which is widely used since some of its events appear to be similar to the clinical pain of humans. The assay in which a dilute solution of formalin is injected into the dorsal hindpaw of a murine produces two ‘phases’ of pain behavior separated by a inactive period. The early phase (Phase I) is probably due to direct activation of nociceptors and the second phase (Phase II) is due to ongoing inflammatory input and central sensitization. Mice were used to determine the potency antinociceptive of piroxicam (1,3,10,and 30 mg/kg), parecoxib (0.3, 1,3,10 and 30 mg/kg), dexketoprofen (3,10,30 and 100 mg/kg) and ketoprofen (3,10,30 and 100 mg/kg). Dose-response for each NSAIDs were created before and after 5 mg/kg of L-NAME i.p. or 5 mg/kg i.p. of 7-nitroindazole. A least-squares linear regression analysis of the log dose–response curves allowed the calculation of the dose that produced 50% of antinociception (ED50) for each drug. The ED50 demonstrated the following rank order of potency, in the phase I: piroxicam > dexketoprofen > ketoprofen > parecoxib and in the phase II: piroxicam > ketoprofen > parecoxib > dexketoprofen. Pretreatment of the mice with L-NAME or 7-nitroindazol induced a significant increase of the analgesic power of the NSAIDs, with a significant reduction of the ED50. It is suggested that NO may be involved in both phases of the trial, which means that nitric oxide regulates the bioactivity of NSAIDs.

Identifying Criteria for Continuous Evaluation of Software Engineers for Reward and Recognition

2016 ◽  
Vol 7 (4) ◽  
pp. 61-78 ◽  
Author(s):  
Sreejith S. S. ◽  
Muthu Mathirajan
Keyword(s):  
Phase I ◽  
Phase Ii ◽  
Employee Performance ◽  
Exploratory Research ◽  
Structured Interviews ◽  
Continuous Evaluation ◽  
Software Engineers ◽  
Two Phases ◽  
R Process ◽  
Reward And Recognition

Reward and Recognition (R&R) should be given to employees in a timely manner, based on continuous evaluation of their performance. Success of an R&R process lies in clear and well defined criteria for continuous evaluation of employee performance. Often such criteria are decided by the organization with no input from the employees. The purpose of this paper is to use qualitative research methods to explore and identify the criteria to be used for continuous employee performance evaluation for R&R in Information Technology organizations, from the perspectives of software engineers (SEs) and project managers (PMs). Exploratory research was conducted in two phases. In Phase I, unstructured interviews are used to elicit information from 7 SEs. Caselets are prepared based on these interviews and 19 criteria are identified. In Phase II, the criteria identified in Phase I are confirmed using content analysis of semi-structured interviews, conducted on relatively larger group of SEs (in stage 1) and PMs (in stage 2). Additionally, 12 criteria are also identified in Phase II. Collectively 31 criteria are identified. The proposed criteria set is expected to comprehensively cover the SE performance on a continuous basis in various dimensions to award R&R.

Assessing Hospital Disaster Readiness Over Time at the US Department of Veterans Affairs

2016 ◽  
Vol 32 (1) ◽  
pp. 46-57 ◽  
Author(s):  
Claudia Der-Martirosian ◽  
Tiffany A. Radcliff ◽  
Alicia R. Gable ◽  
Deborah Riopelle ◽  
Farhad A. Hagigi ◽  
...  
Keyword(s):  
Phase I ◽  
Emergency Management ◽  
Phase Ii ◽  
Veterans Affairs ◽  
Assessment Tools ◽  
Department Of Veterans Affairs ◽  
The Us ◽  
Two Phases ◽  
Hospital Readiness ◽  
Over Time

AbstractIntroductionThere have been numerous initiatives by government and private organizations to help hospitals become better prepared for major disasters and public health emergencies. This study reports on efforts by the US Department of Veterans Affairs (VA), Veterans Health Administration, Office of Emergency Management’s (OEM) Comprehensive Emergency Management Program (CEMP) to assess the readiness of VA Medical Centers (VAMCs) across the nation.Hypothesis/ProblemThis study conducts descriptive analyses of preparedness assessments of VAMCs and examines change in hospital readiness over time.MethodsTo assess change, quantitative analyses of data from two phases of preparedness assessments (Phase I: 2008-2010; Phase II: 2011-2013) at 137 VAMCs were conducted using 61 unique capabilities assessed during the two phases. The initial five-point Likert-like scale used to rate each capability was collapsed into a dichotomous variable: “not-developed=0” versus “developed=1.” To describe changes in preparedness over time, four new categories were created from the Phase I and Phase II dichotomous variables: (1) rated developed in both phases; (2) rated not-developed in Phase I but rated developed in Phase II; (3) rated not-developed in both phases; and (4) rated developed in Phase I but rated not- developed in Phase II.ResultsFrom a total of 61 unique emergency preparedness capabilities, 33 items achieved the desired outcome – they were rated either “developed in both phases” or “became developed” in Phase II for at least 80% of VAMCs. For 14 items, 70%-80% of VAMCs achieved the desired outcome. The remaining 14 items were identified as “low-performing” capabilities, defined as less than 70% of VAMCs achieved the desired outcome.Conclusion:Measuring emergency management capabilities is a necessary first step to improving those capabilities. Furthermore, assessing hospital readiness over time and creating robust hospital readiness assessment tools can help hospitals make informed decisions regarding allocation of resources to ensure patient safety, provide timely access to high-quality patient care, and identify best practices in emergency management during and after disasters. Moreover, with some minor modifications, this comprehensive, all-hazards-based, hospital preparedness assessment tool could be adapted for use beyond the VA.Der-MartirosianC, RadcliffTA, GableAR, RiopelleD, HagigiFA, BrewsterP, DobalianA. Assessing hospital disaster readiness over time at the US Department of Veterans Affairs. Prehsop Disaster Med. 2017;32(1):46–57.

Enhanced muscle glucose metabolism after exercise in the rat: the two phases

1984 ◽  
Vol 246 (6) ◽  
pp. E471-E475 ◽  
Author(s):  
L. P. Garetto ◽  
E. A. Richter ◽  
M. N. Goodman ◽  
N. B. Ruderman
Keyword(s):  
Insulin Sensitivity ◽  
Glucose Metabolism ◽  
Phase I ◽  
Phase Ii ◽  
Muscle Glycogen ◽  
Glucose Utilization ◽  
Glycogen Synthesis ◽  
Moderate Intensity ◽  
Base Line ◽  
Two Phases

Thirty minutes after a treadmill run, glucose utilization and glycogen synthesis in perfused rat skeletal muscle are enhanced due to an increase in insulin sensitivity (Richter et al., J. Clin. Invest. 69: 785-793, 1982). The exercise used in these studies was of moderate intensity, and muscle glycogen was substantially repleted at the time (30 min postexercise) that glucose metabolism was examined. When rats were run at twice the previous rate (36 m/min), muscle glycogen was still substantially diminished 30 min after the run. At this time the previously noted increase in insulin sensitivity was still observed in perfused muscle; however, glucose utilization was also increased in the absence of added insulin (1.5 vs. 4.2 mumol X g-1 X h-1). In contrast 2.5 h after the run, muscle glycogen had returned to near preexercise values, and only the insulin-induced increase in glucose utilization was evident. The data suggest that the restoration of muscle glycogen after exercise occurs in two phases. In phase I, muscle glycogen is depleted and insulin-stimulated glucose utilization and glucose utilization in the absence of added insulin may both be enhanced. In phase II glycogen levels have returned to near base-line values and only the increase in insulin sensitivity persists. It is proposed that phase I corresponds to the period of rapid glycogen repletion that immediately follows exercise and phase II to the period of supercompensation.

Texture Image Segmentation Using Affinity Propagation and Spectral Clustering

2015 ◽  
Vol 29 (05) ◽  
pp. 1555009 ◽  
Author(s):  
Hui Du ◽  
Yuping Wang ◽  
Xiaopan Dong
Keyword(s):  
Image Segmentation ◽  
Spectral Clustering ◽  
Clustering Algorithm ◽  
Clustering Algorithms ◽  
Computational Cost ◽  
Affinity Propagation ◽  
Texture Image ◽  
Texture Image Segmentation ◽  
Two Phases ◽  
Representative Points

Clustering is a popular and effective method for image segmentation. However, existing cluster methods often suffer the following problems: (1) Need a huge space and a lot of computation when the input data are large. (2) Need to assign some parameters (e.g. number of clusters) in advance which will affect the clustering results greatly. To save the space and computation, reduce the sensitivity of the parameters, and improve the effectiveness and efficiency of the clustering algorithms, we construct a new clustering algorithm for image segmentation. The new algorithm consists of two phases: coarsening clustering and exact clustering. First, we use Affinity Propagation (AP) algorithm for coarsening. Specifically, in order to save the space and computational cost, we only compute the similarity between each point and its t nearest neighbors, and get a condensed similarity matrix (with only t columns, where t << N and N is the number of data points). Second, to further improve the efficiency and effectiveness of the proposed algorithm, the Self-tuning Spectral Clustering (SSC) is used to the resulted points (the representative points gotten in the first phase) to do the exact clustering. As a result, the proposed algorithm can quickly and precisely realize the clustering for texture image segmentation. The experimental results show that the proposed algorithm is more efficient than the compared algorithms FCM, K-means and SOM.

scholarly journals Deqi Sensation in Placebo Acupuncture: A Crossover Study on Chinese Medicine Students

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Zhao-hui Liang ◽  
Chang-cai Xie ◽  
Zi-ping Li ◽  
Xiao-ping Zhu ◽  
Ai-ping Lu ◽  
...  
Keyword(s):  
Chinese Medicine ◽  
Phase I ◽  
Phase Ii ◽  
Clinical Trial Registry ◽  
Placebo Acupuncture ◽  
Real Acupuncture ◽  
Group A ◽  
The Difference ◽  
Two Phases ◽  
Group B

Objective. To evaluate the similarity of deqi sensation of real and noninvasive placebo acupuncture in healthy people with knowledge of Chinese medicine.Methods. In a crossover design, volunteers recruited from Chinese medicine college students were randomized to two groups to receive two phases of intervention with a one-week washout interval. In Group A, the participants were firstly treated by real acupuncture and then by sham needle, and the treatment sequence was reversed in Group B. VAS for pain intensity and deqi sensation was evaluated as outcomes.Results. Sixty-three volunteers were recruited and 60 were included and finished the study. In Group A, VAS was higher in Phase I than in Phase II (P=0.017). Only treatment methods were selected as factor to VAS difference (P=0.046) in ANOVA test. More positive deqi was reported in Group A in Phase I when treated by real acupuncture (P=0.039), but the difference was not significant in Phase II (P=0.301).Conclusion. The noninvasive placebo acupuncture device can effetely simulate the deqi sensation as real acupuncture, but it is less likely to evoke the active effect of deqi in real practice. This trial is registered with Chinese Clinical Trial Registry:ChiCTR-ORC-09000505.

The discrepancy between plasma 11-deoxycortisol and ACTH concentrations in a single dose metyrapone test in normal men

1982 ◽  
Vol 101 (1) ◽  
pp. 62-65
Author(s):  
Michihiro Matsuki ◽  
Seikoh Nishida ◽  
Masaharu Horino ◽  
Atsuko Tenku ◽  
Hideki Oyama
Keyword(s):  
Single Dose ◽  
Phase I ◽  
Phase Ii ◽  
Cortisol Level ◽  
Pre Treatment ◽  
Two Phases ◽  
Normal Men

Abstract. A single dose metyrapone test (MTP test) was carried out on 6 normal men by administering 1.0 g of metyrapone at 08.00–09.00 h with and without dexamethasone (DXM-MTP test) pre-treatment. Plasma 11-deoxycortisol, pregnenolone, ACTH and cortisol were measured before administration of the drug, and at hourly intervals for 6 h. In the MTP test, 11-deoxycortisol increased significantly at 1 h with a peak at 5 h, whereas significant increases in pregnenolone and ACTH were not seen until 3 h. There was a definite decrease in the cortisol level at 1 h with the lowest level measured at 2 h. Thus, a time discrepancy between plasma 11-deoxycortisol and ACTH concentrations was observed. The increase in 11-deoxycortisol after metyrapone should be divided into two phases: the increase in phase II (after 3 h) is due to the pituitary ACTH reserve, and that in phase I (the first 2 h) is due to some mechanism other than the pituitary ACTH reserve. The increased amount of 11-deoxycortisol in phase II (218.1 nmol) occupied 60.5% of the total increased amount in phases I and II(360.6 nmol). The cortisol/(cortisol +11-deoxycortisol) ratio reached its lowest point 3 h after metyrapone treatment. This might be due to the initiation of an additional surge in 11-deoxycortisol by the ACTH reserve at 3 h.

The Phase II Urokinase-Streptokinase Pulmonary Embolism Trial

1975 ◽  
Vol 33 (03) ◽  
pp. 464-476 ◽  
Author(s):  
Arthur A Sasahara ◽  
William R Bell ◽  
Toby L Simon ◽  
James M Stengle ◽  
Sol Sherry
Keyword(s):  
Pulmonary Embolism ◽  
Phase I ◽  
Phase Ii ◽  
Randomized Study ◽  
The United States ◽  
Pulmonary Angiography ◽  
Group 12 ◽  
Two Phases ◽  
Comparative Results ◽  
Lung Scanning

SummaryThe controlled clinical trials of thrombolytic agents in the United States have been carried out in two phases, under the auspices of the National Heart and Lung Institute. Phase I was devoted to the comparison of 12-hour Urokinase (12h–UK) followed by heparin (H) with heparin alone in patients with acute pulmonary embolism (Walsh et al. 1969). The results showed that patients treated with UK had more rapid and greater resolution of pulmonary thromboemboli in the first twenty-four hours of therapy than patients treated with H alone, as assessed by serial pulmonary angiography, hemodynamics and lung scanning (The Urokinase Pulmonary Embolism Trial, 1970, 1973 ; Hyers et al. 1970). Because of the relatively small size of the Trial and the low mortality of treated pulmonary embolism, mortality differences were not sought - nor was one found. Although there was early difference in amount of clot resolution, patients treated with H alone showed similar improvement by two weeks.The Phase II Urokinase-Streptokinase Pulmonary Embolism Trial (USPET) was begun to assess the comparative results of UK and Streptokinase (SK) therapy. Because of favorable results obtained with SK in other countries, it was deemed necessary to make this comparison (Browse and James, 1964 ; Hirsh et al. 1968 ; Miller et al. 1969, 1971 ; Chesterman et al. 1969). A third group, 12-hour UK, was added to relate this study (24-hour UK and SK) with the Phase I results which employed only a 12-hour infusion of UK. This Phase II Trial represents the first controlled, randomized study of UK and SK in thromboembolic disorders.

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