A validation study to find highly correlated parameters with visual assessment for clinical evaluation of cosmetic anti-cellulite products

Thirteen long tibia (bovine) bones were utilized in vitro to experimentally extract modal frequencies in the cranial-caudal (C-C) and medial–lateral (M–L) planes. Bones were instrumented with four single-axis accelerometers uniformly placed along the length of the bone and hammer impacted at different locations in both planes. Frequency response function (FRF) and complex mode indicator function (CMIF) techniques were used to identify the modal frequencies. CMIF has an advantage of detecting closely spaced modes by excluding misinterpreted peaks. It was found that the difference between the two methods did not exceed 2.98%. CMIF data were more consistent when varying impact location. The effect of bone's geometrical attributes on modal frequencies was statistically scrutinized and highly correlated parameters were identified. Bone length exhibited high correspondence to frequencies (p < 0.05) for practically all modes. Also, four simple equations were developed, relating modes 1 and 2 in the C-C and M-L planes to bone length. To determine the first and second modal shapes, subset of 6 tibia bones was further instrumented. Mode shapes were extracted in the C-C and M-L planes.

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A methodology for the assessment of unit cost drivers for commercial aircraft

The Aeronautical Journal ◽

10.1017/s0001924000001159 ◽

2006 ◽

Vol 110 (1105) ◽

pp. 173-184

Author(s):

N. L. Tirovolis ◽

V. C. Serghides

Keyword(s):

Cost Estimation ◽

Unit Cost ◽

Aircraft Design ◽

Commercial Aircraft ◽

Technical Data ◽

Cost Drivers ◽

Wide Range ◽

Development Approach ◽

Highly Correlated ◽

Correlated Parameters

Abstract Presented in this paper are the prerequisite steps in a methodology for the identification and assessment of unit cost drivers for use in the development of a new design-oriented unit cost estimation methodology for large commercial jet aircraft with minimum seating capacity of 100 passengers. The work presented here focuses on unit cost, which is a significant element of the total aircraft cost and for the initial aircraft design process in particular. The methodology aims to investigate how aircraft design properties could influence cost. Cost estimation relationships, containing a wide range of the most highly correlated parameters, are retrieved from detailed regression analysis conducted on two different aircraft generation categories. Since the methodology is based on actual cost and technical data, it is accurate both in terms of predicting the aircraft unit cost or conducting cost-comparative studies between different aircraft concepts. The emphasis in this paper is mainly on the development approach and parameter assessments, adopted towards the final unit cost estimation methodology.

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Reactions of field pea cultivars to four races of Fusarium oxysporum f. sp. pisi

Canadian Journal of Plant Science ◽

10.4141/p02-048 ◽

2003 ◽

Vol 83 (2) ◽

pp. 377-379 ◽

Cited By ~ 4

Author(s):

S. Neumann and A. G. Xue

Keyword(s):

Fusarium Oxysporum ◽

Fusarium Wilt ◽

Visual Assessment ◽

Shoot Length ◽

Field Pea ◽

Severity Rating ◽

Race 1 ◽

Growth Chambers ◽

Race 2 ◽

Highly Correlated

Reactions of the 117 field pea cultivars available in Canada were evaluated to the four common races (1, 2, 5, and 6) of Fusarium oxysporum Schl. f. sp. pisi (van Hall) Sny. and Hans, the causal agent of fusarium wilt, in growth chambers. Based on the visual assessment of foliar wilt symptoms, 49 cultivars were resistant to at least one of the four races, and the remaining 68 cultivars were susceptible to all four races. Of these resistant cultivars, Ascona and 44 other cultivars were resistant to race 1; Impala to race 2; Aladin to races 1 and 2; and Radley and Princess to races 2, 5, and 6. In an effort to standardize the methodology for screening field pea for resistance to the pathogen, other quantitative parameters including shoot length, vascular discoloration, and shoot and root dry weights were evaluated on selected cultivars. Correlation analysis revealed that foliar wilt symptoms and the reduction in shoot length were highly correlated (r = -0.90, P < 0.01). The result suggests that the reduction in shoot length could be used to supplement the visual severity rating for fusarium wilt in field pea. Key words: Field pea, Pisum sativum, fusarium wilt, Fusarium oxysporum f. sp. pisi, resistance

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NAS-50 and NAS-40: New scales for the assessment of self-control

Polish Psychological Bulletin ◽

10.1515/ppb-2016-0041 ◽

2016 ◽

Vol 47 (3) ◽

pp. 346-355 ◽

Cited By ~ 2

Author(s):

Edward Nęcka ◽

Radosław Wujcik ◽

Jarosław Orzechowski ◽

Aleksandra Gruszka ◽

Beata Janik ◽

...

Keyword(s):

Validation Study ◽

Assessment Tool ◽

Self Control ◽

General Intelligence ◽

Proactive Control ◽

Control Scale ◽

Goal Maintenance ◽

Individual Trait ◽

Self Reports ◽

Highly Correlated

Abstract In this paper, we present a new questionnaire for the assessment of self-control as an individual trait. We describe the process of construction of this assessment tool. We also report the results of relevant validation studies. The questionnaire has two independent versions, one based on self-reports (NAS-50) and another one based on other-reports (NAS-40). The first version consists of five subscales (10 items each), called Initiative and Persistence (IP), Proactive Control (PC), Switching and Flexibility (SF), Inhibition and Adjournment (IA), and Goal Maintenance (GM). Seven samples of participants (N = 934 altogether) took part in the validation study. The second version has not been split into subscales. Both versions obtained satisfactory indices of internal consistency, assessed with Cronbach’s alpha (for NAS- 50 total score a = .861, for the subscales a between .726 and .867; for NAS-40 a = .844). The NAS-50 and NAS-40 scores were highly correlated with other measures of self-control, including Tangney, Baumeister, and Boone’s (2004) self-control scale. They also proved to be entirely independent of general intelligence. In conclusion, both versions can be regarded reliable and valid enough, and therefore suitable for the assessment of trait self-control for research purposes.

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Development and Clinical Validation of CT-Based Regional Centiloid Method for Amyloid PET

10.21203/rs.3.rs-961603/v1 ◽

2021 ◽

Author(s):

Soo-Jong Kim ◽

Hongki Ham ◽

Yu Hyun Park ◽

Yeong Sim Choe ◽

Young Ju Kim ◽

...

Keyword(s):

Validation Study ◽

Neuropsychological Performance ◽

Amyloid Pet ◽

Clinical Validation ◽

Target Region ◽

Posterior Cingulate ◽

Accessible Method ◽

Mri Scans ◽

Highly Correlated ◽

Common Target

Abstract Background: We developed and validated CT-based regional Centiloid. A CT-based regional Centiloid was developed and validated in the present study. Methods: For development ofMRI-based or CT-based regional CLs,the cohort consist of 63 subjects (20 young controls (YC) and18 old controls (OC), and 25 Alzheimer’s disease dementia (ADD)).We used direct comparison of FMM-FBB CL (dcCL) method using MRI and CT images to define a common target region and six regional VOIs including the frontal, temporal, parietal, posterior cingulate, occipital and striatal regions. Global and regional dcCL scales were compared between MRI-based and CT-based methods. For clinical validation, cohortconsisted of 2,245subjects (627 in CN, 933 in MCI, and 685 in ADD). Results: Both MRI-based and CT-based dcCL scales showed that FMM and FBB were highly correlated with each other, globally and regionally (R2 = 0.96~0.99). Both FMM and FBB showed that CT-based regional dcCL scales were highly correlated with MRI-based regional dcCL scales (R2 = 0.97~0.99). Absolute differences in regional CL scales between CT-based and MRI-based methods seemed to be relatively insignificant (p>0.05). In our clinical validation study, the G(-)R(+) and G(+)Str(+) groups predict worse neuropsychological performance than the G(-)R(-) and the G(+)Str(-) groups (p< 0.05) respectively.Conclusions: Our findings suggested that it is feasible to convert FMM or FBB dcSUVR values into the dcCL scales regionally without additional MRI scans, which might in turn become a more easily accessible method for researchers and be applicable to a variety of different conditions.

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The Borderline Syndrome Index: a Validation Study using the Personality Assessment Schedule

The British Journal of Psychiatry ◽

10.1192/bjp.168.1.72 ◽

1996 ◽

Vol 168 (1) ◽

pp. 72-75 ◽

Cited By ~ 10

Author(s):

M. J. Marlowe ◽

K. O'Neill-Byrne ◽

F. Lowe-Ponsford ◽

J. P. Watson

Keyword(s):

Validation Study ◽

Personality Assessment ◽

Case Control ◽

Screening Instrument ◽

Screen Questionnaire ◽

Borderline Syndrome ◽

The Usa ◽

Highly Correlated ◽

The Uk ◽

Symptom Measures

BackgroundThis study examines the validity and screening properties of the Borderline Syndrome Index – BSI (developed in the USA) for categories of the Personality Assessment Schedule – PAS (developed in the UK).MethodPatients were recruited by case control sampling. Chance corrected agreement between instruments and screening properties of the BSI were calculated.ResultsThe BSI proved a moderately sensitive but non-specific screen. Questionnaire scores were highly correlated with symptom measures.ConclusionsThe results do not support the validity of the BSI or its use as a screening instrument. BSI scores may be distorted by current symptoms.

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INVERSION OF TWO‐DIMENSIONAL RESISTIVITY AND INDUCED‐POLARIZATION DATA

Geophysics ◽

10.1190/1.1440854 ◽

1978 ◽

Vol 43 (4) ◽

pp. 788-803 ◽

Cited By ~ 80

Author(s):

W. H. Pelton ◽

L. Rijo ◽

C. M. Swift,

Keyword(s):

Finite Element ◽

Ridge Regression ◽

Data Bank ◽

Induced Polarization ◽

Forward Problem ◽

Data Sets ◽

Two Dimensional ◽

Polarization Data ◽

Highly Correlated ◽

Correlated Parameters

A fast ridge regression inversion technique has been devised for the interpretation of simple two‐dimensional resistivity and induced‐polarization data. The program will determine the rectangular source under a single layer of overburden which best fits the observed data. Several advantages are derived from using the ridge regression method; they include convergence from very poor initial guesses, stability in the presence of high‐frequency geologic noise, readily obtained estimates of parameter statistics, and the ability for simultaneous inversion of multiple data sets. Unfortunately, each ridge regression inversion requires a great many forward problem evaluations; thus in order to achieve speed and reasonable cost, it is essential to reduce the calculation time for the forward problem to an absolute minimum. One method of achieving this is to store in the computer a data bank containing solutions for the entire range of expected parameter combinations. The forward problem then reduces to numerical interpolation between these precalculated data sets. For compilation of the data bank of forward solutions, two main numerical methods were investigated: the finite element and transmission‐surface algorithms. Although these algorithms are conceptually quite different, the resulting matrix equations are very similar. The efficiency of either method depends mainly on the scheme chosen for solving the resultant large system of linear equations. Once the data bank has been created, it is possible to obtain inverse solutions for less cost than the computation of one finite element or transmission‐surface forward problem. Tests on theoretical data and field data show the inversion technique to be reasonably accurate, stable, and fast. The statistics estimated by the inversion program provide additional useful information on the uncertainty in the parameters of the derived model and on high correlations between parameters. The most highly correlated parameters are, as might be anticipated, the resistivity and the width of thin conductive bodies. Two practical methods for carrying out inversion in spite of highly correlated parameters are, preferably, to add extra data sets which provide more information on some of the parameters or, alternatively, to fix some of the parameters at geologically reasonable values and invert to a more restricted model.

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Analysis of the Parametric Correlation in Mathematical Modeling of In Vitro Glioblastoma Evolution Using Copulas

Mathematics ◽

10.3390/math9010027 ◽

2020 ◽

Vol 9 (1) ◽

pp. 27

Author(s):

Jacobo Ayensa-Jiménez ◽

Marina Pérez-Aliacar ◽

Teodora Randelovic ◽

José Antonio Sanz-Herrera ◽

Mohamed H. Doweidar ◽

...

Keyword(s):

Mathematical Models ◽

Added Value ◽

Strong Correlations ◽

Cancer Evolution ◽

High Cell Concentration ◽

Hypoxic Conditions ◽

Highly Correlated ◽

Correlated Parameters

Modeling and simulation are essential tools for better understanding complex biological processes, such as cancer evolution. However, the resulting mathematical models are often highly non-linear and include many parameters, which, in many cases, are difficult to estimate and present strong correlations. Therefore, a proper parametric analysis is mandatory. Following a previous work in which we modeled the in vitro evolution of Glioblastoma Multiforme (GBM) under hypoxic conditions, we analyze and solve here the problem found of parametric correlation. With this aim, we develop a methodology based on copulas to approximate the multidimensional probability density function of the correlated parameters. Once the model is defined, we analyze the experimental setting to optimize the utility of each configuration in terms of gathered information. We prove that experimental configurations with oxygen gradient and high cell concentration have the highest utility when we want to separate correlated effects in our experimental design. We demonstrate that copulas are an adequate tool to analyze highly-correlated multiparametric mathematical models such as those appearing in Biology, with the added value of providing key information for the optimal design of experiments, reducing time and cost in in vivo and in vitro experimental campaigns, like those required in microfluidic models of GBM evolution.

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