scholarly journals On the Classification of Colored Textures From a Texture-Ranking Experiment: Observers Ability of Discrimination Quantification

2020 ◽  
Vol 10 (1) ◽  
pp. 1
Author(s):  
Amadou Sawadogo ◽  
Dominique Lafon ◽  
Simplice Dossou-Gbété
Keyword(s):  
Test Procedure ◽  
Physical Method ◽  
Ratio Test ◽  
Visual Contrast ◽  
Physical Scale ◽  
Texture Type ◽  
Discrimination Parameter ◽  
Post Hoc ◽  
Horizontal Grating

This paper is devoted to the construction of Fechnerian scales on a physical dimension of investigated colored textures. For this purpose, we considered the extension of the Mallows-Bradley-Terry model for the analysis of the data collected from a contrast-sorting experiment. A likelihood ratio test procedure was proposed in order to choose between the two following hypotheses: discrimination and non-discrimination between the investigated stimuli. In addition, post-hoc analyzes allowed us to find out which of the stimuli differ from the others. Our findings indicate that the subjective attribute of visual contrast appears to be a psycho physical scale that maps to the physical scale corresponding to the Michelson contrast. Mainly, the estimates of the model index of discrimination parameter of the stimuli show that the ability of the observers to discriminate between the textures according to the visual contrast varies with respect to the color ranges and the textures types. According to the luminance contrasts ability of discrimination, the Isotropic texture type is the best, followed by the Random-dots texture type, then by the Horizontal grating type and the Vertical grating type is the least. The Fechnerian scales on the physical dimension of the Michelson contrast of the colored textures depend on the chromaticness of the colored textures phases and the texture types. The psycho physical method of identification would be the best when determining the related thresholds.

scholarly journals Pain in emergency units: correlation with risk classification categories

2018 ◽  
Vol 26 (0) ◽  
Author(s):  
Wandressa Letícia Viveiros ◽  
Meiry Fernanda Pinto Okuno ◽  
Cássia Regina Vancini Campanharo ◽  
Maria Carolina Barbosa Teixeira Lopes ◽  
Gabriella Novelli Oliveira ◽  
...  
Keyword(s):  
Signs And Symptoms ◽  
Medical Specialty ◽  
Cross Sectional Study ◽  
Risk Classification ◽  
Moderate Intensity ◽  
Ratio Test ◽  
Intense Pain ◽  
Cross Sectional ◽  
Mild Pain

ABSTRACT Objectives: to correlate risk classification categories with the level of pain of patients in an emergency service. Method: cross-sectional study carried out in the Risk Classification of 611 patients. The variables studied were: age, gender, comorbidities, complaint duration, medical specialty, signs and symptoms, outcome, color attributed in the risk classification of and degree of pain. We used Analysis of Variance, a Chi-Square test and a Likelihood Ratio test. Results: the average age was 42.1 years (17.8); 59.9% were women; the green (58.9%) and yellow (22.7%) risk classification prevailed and hypertension (18.3%) was the most common Comorbidity. The most frequent pain intensity was moderate (25.9%). In the red category, patients presented a higher percentage of absence of pain; in the blue, mild pain; and in the green, yellow and orange categories, there was a greater percentage of intense pain (p < 0.0001). Conclusion: among the patients who presented pain, the majority reported moderate intensity. Regarding risk categories, most patients in the red category did not report pain. Those who were classified as green, yellow and orange, reported mostly intense pain. On the other hand, patients in the blue category reported predominantly mild pain.

333. HETEROGENEITY OF GENE EXPRESSION IN BOVINE SMALL FOLLICLES

2010 ◽  
Vol 22 (9) ◽  
pp. 133
Author(s):  
N. Hatzirodos ◽  
H. F. Irving-Rodgers ◽  
R. J. Rodgers
Keyword(s):  
Granulosa Cells ◽  
Bovine Genome ◽  
Rna Isolation ◽  
Lh Receptor ◽  
False Discovery ◽  
Expression Of Genes ◽  
Post Hoc ◽  
Gene Frequency Distribution ◽  
Small Follicle

Small antral follicles <5 mm in bovine ovaries undergo one of two fates: further growth and selection to become the dominant follicle for ovulation, or atresia. Atresia can occur before, during or after selection. As follicle grow past >5 mm there is upregulation in expression of focimatrix genes and later upregulation of the LH receptor and steroidogenic enzymes, especially aromatase, in the granulosa cells. For follicles at sizes >5 mm entering atresia the granulosa cells are the first in the follicle to die. Thus expression of genes in granulosa cells is critical to the fate of the follicle. To examine granulosa cells of small follicles we collected bovine ovaries and dissected follicles, removed part of the follicle wall for subsequent classification of health or atresia, and harvested the remaining granulosa cells for RNA isolation. Follicles examined included small follicles (<5 mm), both healthy (n = 10) and atretic (n =5), and healthy large follicles (>10 mm, n = 4). RNA was hybridized to Affymetrix GeneChip Bovine Genome Arrays and the results were analysed using Partek Genomics Suite software. The number of genes which were 2 fold differentially regulated between large and small follicles by Benjamini Hochberg post hoc test (False Discovery Rate, P < 0.05) was 2408 and between healthy and atretic small follicles was 4931. The coefficient of variation (CV; SD/mean × 100) for the expression level of each gene for each group was calculated. A gene frequency distribution indicated greater heterogeneity in expression levels in small follicles in comparison to large follicles. Furthermore, the greatest variability in genes in small follicles includes those that are either up or down regulated due to atresia or growth. We therefore conclude that variability in small follicles is a consequence of alternative fates that small follicle can undergo.

scholarly journals Group Tests for High-dimensional Failure Time Data with the Additive Hazards Models

2017 ◽  
Vol 13 (1) ◽  
Author(s):  
Dandan Jiang ◽  
Jianguo Sun
Keyword(s):  
Failure Time ◽  
Numerical Study ◽  
Test Procedure ◽  
High Dimensional ◽  
Ratio Test ◽  
Time Data ◽  
Genetic Studies ◽  
Additive Hazards ◽  
Hazards Model ◽  
Or Genes

AbstractStatistical analysis of high-dimensional data has been attracting more and more attention due to the abundance of such data in various fields such as genetic studies or genomics and the existence of many interesting topics. Among them, one is the identification of a gene or genes that have significant effects on the occurrence of or are significantly related to a certain disease. In this paper, we will discuss such a problem that can be formulated as a group test or testing a group of variables or coefficients when one faces right-censored failure time response variable. For the problem, we develop a corrected variance reduced partial profiling (CVRPP) linear regression model and a likelihood ratio test procedure when the failure time of interest follows the additive hazards model. The numerical study suggests that the proposed method works well in practical situations and gives better performance than the existing one. An illustrative example is provided.

scholarly journals Action Thresholds for Summer Fungicide Sprays and Sequential Classification of Apple Scab Incidence

Plant Disease ◽  
2009 ◽  
Vol 93 (5) ◽  
pp. 490-498 ◽  
Author(s):  
Odile Carisse ◽  
Catherine Meloche ◽  
Guy Boivin ◽  
Tristan Jobin
Keyword(s):  
Decision Making ◽  
Monte Carlo ◽  
Monte Carlo Simulations ◽  
Sequential Sampling ◽  
Apple Scab ◽  
Parameter Estimates ◽  
Ratio Test ◽  
Sample Number ◽  
Action Thresholds

The objectives of this study were to establish scab incidence thresholds at which summer fungicide sprays should be initiated and to develop sequential sampling for classification plans to facilitate decision making. The relationship between proportion of scabbed leaves per shoot and percent scabbed fruits at harvest was established based on data collected in both experimental and commercial orchards. Action threshold at which fungicide spray program should be initiated in order to maintain fruit scab at harvest below 2% was established at 0.006 scabbed leaves per shoot; hence incidence thresholds of 0.005 and 0.01 scabbed leaves per shoot were evaluated. Sequential sampling for classification procedures (SSCP), using the Wald's sequential probability ratio test (SPRT), were developed based on a beta-binomial distribution and using parameter estimates of the binary power law. Monte Carlo simulations were used to establish the probability of classifying mean scab incidence as less than the action thresholds (pth = 0.005 and pth = 0.01). Operating characteristic (OC) and average sample number (ASN) curves were established for eight combinations of stop lines and error levels (α and β). Based on the results of the Monte Carlo simulations, four sets of stop lines (two for each pth threshold) were selected for further evaluation. Bootstrap simulations of 50 data sets indicated that both the OC and ASN curves for each of the four pairs of stop lines were similar to OC and ASN values determined by Monte Carlo simulation. When validated with data not used to construct the models, the SSCPs provided the appropriate classification in 98 and 95% of the simulations for the pth = 0.005 and pth = 0.01 (α = 0.05 and β = 0.10), respectively. The sequential sampling plans developed in this study should allow for rapid and accurate classification of the incidence of apple scab on leaves, and aid in sampling for summer scab management decision making.

scholarly journals Determination of the Sensitivity and Thixotropic Effects of Clay Soil for Selected Sites in Diwaniya City - Iraq

2020 ◽  
Vol 55 (2) ◽  
Author(s):  
Abdul-Kareem H. Al-Rubaiee ◽  
Rand S. Al Salami
Keyword(s):  
Clay Soil ◽  
Experimental Tests ◽  
Test Methods ◽  
Ratio Test ◽  
Strength Ratio ◽  
Special Test ◽  
Liquidity Index ◽  
Low Sensitivity

This paper is conducted to determine the sensitivity and thixotropic effects of clay soil for selected sites in Diwaniya city which are: (Dawr Aldubbat, Al-Zawra square, 14 Ramadan square, Al'iiskan Alaqadim and Military square). The main aim of this investigation is to study the sensitivity and thixotropy of clay soil, and determination and classification of soils to (Insensitive), (slightly to very sensitive) and (slightly to extra quick)) relying on special test methods in sensitivity and thixotropic phenomena. The experimental tests that were done including geotechnical, chemical and mineralogical tests to natural soils and special tests were for the identification and classification of sensitivity of soils. The results of sensitivity of soils test displayed low to medium for all the types of the soils in the study area. The results of the thixotropic strength ratio test showed a small increase in thixotropic strength ratio values with time. The results of Atterberg limits test indicated that increasing the proportion of the clay causes an increase in the plasticity index of the soil. While the results of the liquidity index varied from 0.24 to 0.70, which reflects the low sensitivity of the clay soil in the study area.

scholarly journals Immune response to vaccines is maintained in patients treated with dimethyl fumarate

2017 ◽  
Vol 5 (1) ◽  
pp. e409 ◽  
Author(s):  
Christian von Hehn ◽  
Jonathan Howard ◽  
Shifang Liu ◽  
Ven Meka ◽  
Joe Pultz ◽  
...  
Keyword(s):  
Immune Response ◽  
T Cell ◽  
Humoral Response ◽  
Dimethyl Fumarate ◽  
Open Label ◽  
Relapsing Remitting ◽  
Pneumococcal Serotype ◽  
Post Hoc ◽  
Serum Igg Levels

Objectives:To investigate the immune response to vaccinations in patients with relapsing forms of MS treated with delayed-release dimethyl fumarate (DMF) vs nonpegylated interferon (IFN).Methods:In this open-label, multicenter study, patients received 3 vaccinations: (1) tetanus-diphtheria toxoid (Td) to test T-cell–dependent recall response, (2) pneumococcal vaccine polyvalent to test T-cell–independent humoral response, and (3) meningococcal (groups A, C, W-135, and Y) oligosaccharide CRM197 conjugate to test T-cell–dependent neoantigen response. Eligible patients were aged 18–55 years, diagnosed with relapsing-remitting MS (RRMS), and either treated for ≥6 months with an approved dose of DMF or for ≥3 months with an approved dose of nonpegylated IFN. Primary end point was the proportion of patients with ≥2-fold rise in antitetanus serum IgG levels from prevaccination to 4 weeks after vaccination.Results:Seventy-one patients (DMF treated, 38; IFN treated, 33) were enrolled. The mean age was 45.3 years (range 27–55); 86% were women. Responder rates (≥2-fold rise) to Td vaccination were comparable between DMF- and IFN-treated groups (68% vs 73%). Responder rates (≥2-fold rise) were also similar between DMF- and IFN-treated groups for diphtheria antitoxoid (58% vs 61%), pneumococcal serotype 3 (66% vs 79%), pneumococcal serotype 8 (95% vs 88%), and meningococcal serogroup C (53% vs 53%), all p > 0.05. In a post hoc analysis, no meaningful differences were observed between groups in the proportion of responders when stratified by age category or lymphocyte count.Conclusions:DMF-treated patients mount an immune response to recall, neoantigens, and T-cell–independent antigens, which was comparable with that of IFN-treated patients and provided adequate seroprotection.ClinicalTrials.gov identifier:NCT02097849.Classification of evidence:This study provides Class II evidence that patients with RRMS treated with DMF respond to vaccinations comparably with IFN-treated patients.

Morphological separation of aphid species Cryptomyzus leonuri Bozhko, 1961 and Cryptomyzus alboapicalis (Theobald, 1916) (Hemiptera: Sternorrhyncha: Aphididae)

Biologia ◽  
2012 ◽  
Vol 67 (5) ◽  
Author(s):  
Jekaterina Bašilova ◽  
Rimantas Rakauskas
Keyword(s):  
A Priori ◽  
Morphological Characters ◽  
Aphid Species ◽  
Stepwise Discriminant Analysis ◽  
Morphological Identification ◽  
Correct Identification ◽  
Forward Stepwise ◽  
Leonurus Cardiaca ◽  
Post Hoc

AbstractAphids of the species Cryptomyzus alboapicalis (Theobald, 1916) and Cryptomyzus leonuri Bozhko, 1961 are very similar morphologically, although exploit different host plants (Lamium album and Leonurus cardiaca, respectively). Morphological characters proposed for the separation of this species couple in the identification key to European Cryptomyzus species appeared to be of little discriminatory power when applied to apterous viviparous females from clonal lineages, whilst alate viviparous females of C. leonuri were not included in the key at all. The aim of this study was to find reliable morphological characters and their combinations for the separation of apterous and alate viviparous females of C. alboapicalis and C. leonuri. Forward stepwise discriminant analysis based on characters without statistically significant (P < 0.05) correlation (|r| ≥ 0.50) with body length resulted in canonical functions enabling correct classification of 95–100% of specimens from clonal lineages involved in the analysis with a priori specified group membership. The post hoc classification gave 95–100% correct identification of individuals from clonal and 85–100% from field-collected samples. The discriminative values of single morphological characters and canonical functions are discussed and modified key for the morphological identification of C. alboapicalis and C. leonuri apterous and alate viviparous females is suggested.

scholarly journals Abnormal Adaptation of Visual Contrast Sensitivity In Multiple Sclerosis Patients

1981 ◽  
Vol 8 (3) ◽  
pp. 227-234 ◽  
Author(s):  
J. Raymond ◽  
D. Regan ◽  
T.J. Murray
Keyword(s):  
Multiple Sclerosis ◽  
Contrast Sensitivity ◽  
Test Procedure ◽  
Acute Stage ◽  
Visual Contrast ◽  
Contrast Adaptation ◽  
Spatial Frequencies ◽  
Permanent Loss ◽  
Multiple Sclerosis Patients ◽  
Visual Contrast Sensitivity

SUMMARY:Some multiple sclerosis patients with 20/20 acuity complain of poor vision. In a previous report we accounted for this in our patient group by showing that multiple sclerosis had caused a depression of contrast sensitivity while sparing visual acuity. In this study we investigated whether some of this measured depression might be due to abnormally rapid or severe adaptation during the test procedure rather than a true permanent loss. Our finding was opposite to this supposition: adaptation was abnormally slight and/ or slow.Depressed contrast sensitivity was not well correlated with abnormal adaptation to contrast. In patients whose contrast sensitivity losses were restricted to a band of spatial frequencies, we found no evidence that abnormalities of contrast adaptation were restricted to this same spatial frequency band. Further evidence of dissociation between abnormal contrast sensitivity and abnormal contrast adaptation is that some patients with normal contrast sensitivity showed abnormally small adaptation.Our finding of abnormally slow or abnormally small contrast adaptation in MS patients seems to conflict with Enoch et al’s (1978) report of abnormally great adaptation after inspecting a bright stimulus. This apparent disagreement may be due to their use of prior dark adaptation, very bright adapting stimuli and patients in the acute stage of retrobulbar neuritis.

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