The following is the abstract of the article discussed in the subsequent letter:

2004 ◽  
Vol 97 (6) ◽  
pp. 2395-2397 ◽  
Author(s):  
Jeffrey H. Silber
Keyword(s):  
Normal Population ◽  
Wall Stress ◽  
Z Score ◽  
Fiber Stress ◽  
Lv Mass ◽  
Wide Range ◽  
Z Scores ◽  
The Difference ◽  
Range Of Values ◽  
Valvar Aortic Stenosis

Wall stress, although commonly used as an index of afterload, fails to take into account forces generated within the wall of the left ventricle (LV) that oppose systolic fiber shortening. Wall stress may, therefore, misrepresent fiber stress, the force resisting fiber shortening, particularly in the presence of an abnormal LV thickness-to-dimension ratio ( h/ D). M-mode LV echocardiograms were obtained from 207 patients with a wide range of values for LV mass and/or h/ D. Diagnoses were valvar aortic stenosis, coarctation repair, anthracycline treated, and severe aortic and/or mitral regurgitation. End-systolic wall stress (WSes) and fiber stress (FSes) were expressed as age-corrected Z scores relative to a normal population. The difference between WSes and FSes was extreme when h/ D was elevated or reduced [WSes Z score − FSes Z score = 0.14 × ( h/ D)−1.47 − 2.13; r = 0.78, P < 0.001], with WSes underestimating FSes when h/ D was increased and overestimating FSes when h/ D was decreased. Analyses of myocardial mechanics based on wall stress have limited validity in patients with abnormal ventricular geometry.

Wall stress misrepresents afterload in children and young adults with abnormal left ventricular geometry

2002 ◽  
Vol 92 (3) ◽  
pp. 1053-1057 ◽  
Author(s):  
Thomas L. Gentles ◽  
Steven D. Colan
Keyword(s):  
Normal Population ◽  
Wall Stress ◽  
Left Ventricular ◽  
Left Ventricular Geometry ◽  
Z Score ◽  
Fiber Stress ◽  
Ventricular Geometry ◽  
Wide Range ◽  
Z Scores ◽  
The Difference

Wall stress, although commonly used as an index of afterload, fails to take into account forces generated within the wall of the left ventricle (LV) that oppose systolic fiber shortening. Wall stress may, therefore, misrepresent fiber stress, the force resisting fiber shortening, particularly in the presence of an abnormal LV thickness-to-dimension ratio ( h/ D). M-mode LV echocardiograms were obtained from 207 patients with a wide range of values for LV mass and/or h/ D. Diagnoses were valvar aortic stenosis, coarctation repair, anthracycline treated, and severe aortic and/or mitral regurgitation. End-systolic wall stress (WSes) and fiber stress (FSes) were expressed as age-corrected Z scores relative to a normal population. The difference between WSes and FSes was extreme when h/ D was elevated or reduced [WSes Z score − FSes Z score = 0.14 × ( h/ D)−1.47 − 2.13; r = 0.78, P < 0.001], with WSes underestimating FSes when h/ D was increased and overestimating FSes when h/ D was decreased. Analyses of myocardial mechanics based on wall stress have limited validity in patients with abnormal ventricular geometry.

scholarly journals The Mystery of the Z-Score

Aorta ◽  
2016 ◽  
Vol 04 (04) ◽  
pp. 124-130 ◽  
Author(s):  
Alexander Curtis ◽  
Tanya Smith ◽  
Bulat Ziganshin ◽  
John Elefteriades
Keyword(s):  
Thoracic Aorta ◽  
Normal Population ◽  
Pediatric Population ◽  
Treatment Strategies ◽  
Z Score ◽  
Web Based ◽  
Geographical Regions ◽  
Z Scores ◽  
American Society ◽  
Size Limits

AbstractReliable methods for measuring the thoracic aorta are critical for determining treatment strategies in aneurysmal disease. Z-scores are a pragmatic alternative to raw diameter sizes commonly used in adult medicine. They are particularly valuable in the pediatric population, who undergo rapid changes in physical development. The advantage of the Z-score is its inclusion of body surface area (BSA) in determining whether an aorta is within normal size limits. Therefore, Z-scores allow us to determine whether true pathology exists, which can be challenging in growing children. In addition, Z-scores allow for thoughtful interpretation of aortic size in different genders, ethnicities, and geographical regions. Despite the advantages of using Z-scores, there are limitations. These include intra- and inter-observer bias, measurement error, and variations between alternative Z-score nomograms and BSA equations. Furthermore, it is unclear how Z-scores change in the normal population over time, which is essential when interpreting serial values. Guidelines for measuring aortic parameters have been developed by the American Society of Echocardiography Pediatric and Congenital Heart Disease Council, which may reduce measurement bias when calculating Z-scores for the aortic root. In addition, web-based Z-score calculators have been developed to aid in efficient Z-score calculations. Despite these advances, clinicians must be mindful of the limitations of Z-scores, especially when used to demonstrate beneficial treatment effect. This review looks to unravel the mystery of the Z-score, with a focus on the thoracic aorta. Here, we will discuss how Z-scores are calculated and the limitations of their use.

scholarly journals ARCHETYPE AND LOGOS OF FURNACE AND FIREPLACE

2019 ◽  
Vol 10 (2) ◽  
pp. 353-372
Author(s):  
Svetlana V. Gerasimova
Keyword(s):  
Human Behavior ◽  
World Culture ◽  
Semiotic System ◽  
Wide Range ◽  
Close Relationship ◽  
The Difference ◽  
Range Of Values ◽  
New Time

The article is literary in nature: the example of the furnace shows the difference between the logos and the archetype, as well as the principles of modifying the logos into an archetype. The aim of the work is to systematize a wide range of values of the archetypal symbol of the furnace, finding the sacred logos to which they ascend. The article is written on the material of ancient mythology and literature of the New Time: the archetypical images, related to the archetype of the furnace, such as the affected heel, fire, serpent, are analyzed - their relevance to world culture and literature, related to their repeatability and stability, is proved. So it is concluded that there is a close relationship between all the elements of the semiotic system: as a result of the disappearance of one of the furnaces, the archetype of the furnace, from everyday culture, the attitude and principles of human behavior changed, which radically affected the course of history.

scholarly journals Preferential preservation of visuospatial memory over verbal memory in the Old Order Amish

2021 ◽  
Author(s):  
Michael B. Prough ◽  
Laura J. Caywood ◽  
Jason E. Clouse ◽  
Sharlene D. Herington ◽  
Susan H. Slifer ◽  
...  
Keyword(s):  
Verbal Memory ◽  
Memory Loss ◽  
Cognitive Status ◽  
Visuospatial Memory ◽  
Z Score ◽  
Delayed Recall ◽  
Old Order Amish ◽  
Old Order ◽  
Z Scores ◽  
The Difference

Background: While studying cognition in the Old Order Amish (OOA), we have observed strong performance on the constructional praxis delayed recall (CPDR) as compared to other cognitive tests, independent of overall cognitive status. This may indicate a preferential preservation of visuospatial memory in this population. Here, we investigate this by comparing the CPDR to the word list delayed recall (WLDR) within the OOA, as well as by comparing these results to a non-Amish cohort. Method: 420 OOA individuals in Indiana/Ohio age 66-95 who had complete data for the CPDR and WLDR were included. From the non-Amish CERAD cohort, 401 individuals age 60-96 with the same tests were included. For both cohorts, education-adjusted Z-scores were calculated for the CPDR and WLDR. The difference between the CPDR Z-score and the WLDR Z-score was calculated as a measure of the preservation of visuospatial memory over verbal memory. T-tests were first used to compare the tests within both cohorts and then stratified by case/control status. Linear regression was then used to investigate the effects of age, sex, cognitive status, and cohort on the Z-scores and difference between Z-scores. Additional t-tests and regressions were then performed to further investigate the effect of sex and its interaction with cohort. Result: We found a significantly better performance on CPDR over WLDR in every cognitive status group in the OOA, but not in all groups of the CERAD cohort. After controlling for age, sex, and cognitive status, this preferential preservation remains significantly higher in the Amish, with being in the Amish cohort increasing the difference between Z-scores by an average of 0.615 units when compared to being in the CERAD cohort. When adjusting for age, sex, cognitive status, and cohort, the interaction between cohort and sex is significant, with the Amish males exhibiting a greater difference between Z-scores compared to other groups, with a significant interaction value of 0.676. Discussion: Overall, these findings suggest that the OOA preferentially preserve visuospatial memory over verbal memory, regardless of cognitive status. This effect is particularly strong in OOA males. In summary, this study gives additional evidence that the Amish exhibit unique patterns of memory loss and aging, with a preferential preservation of visuospatial memory over verbal memory. Additional studies are needed to further explain this phenomenon.

Neurocognitive outcomes of head and neck chemoradiotherapy: A pilot study

2009 ◽  
Vol 27 (15_suppl) ◽  
pp. 6068-6068
Author(s):  
H. K. Gan ◽  
L. J. Bernstein ◽  
J. Brown ◽  
J. Ringash ◽  
M. Vakilha ◽  
...  
Keyword(s):  
Head And Neck ◽  
Normative Data ◽  
Affective State ◽  
Z Score ◽  
Curative Intent ◽  
Z Scores ◽  
The Difference ◽  
Mean Time ◽  
Univariate Analyses

6068 Background: Evidence suggests cancer-related treatments affect cognition. To our knowledge, no studies have systematically investigated cognitive impairment in head and neck cancer (HNC) patients (pts). We assessed ten relapse-free HNC pts after curative-intent radiotherapy (RT), half of whom received cisplatin (Cp). Methods: Pts completed a 2-hr battery of tests/questionnaires assessing objective cognitive function (CF), subjective CF, quality of life and affect. Objective measures of CF were transformed to Z-scores (mean=0, standard deviation=1) using age normative data. A negative value for the Difference Score (DS=Z-score minus IQ score) in each tested domain indicates cognitive deterioration as IQ is a pre-morbid estimate of pts’ CF. A Global Deficit Score (GDS) was obtained by averaging the DS of all tested CF domains. Results: Pt demographics were: M:F=8:2; mean age=58 yrs(range 47–66); mean smoking pack yrs=15(0–45); mean drinks/week=7(0–25); mean IQ Z-score=+1.2(-1.0 to +2.0), mean school yrs=15 (6–18) and mean time post treatment=20 mo(9–41). All pts completed the battery within 2 hr. Nine participants appeared to have impaired CF based on negative DS and GDS scores ( Table 1 ). Exploratory univariate analyses showed trends that higher RT dose and Cp use were associated with increased impairment but cytokines, anemia, hormonal status and affective state were not. Conclusions: This feasibility study suggests cancer-related treatment affects cognition in HNC survivors. A longitudinal study is underway. [Table: see text] No significant financial relationships to disclose.

Comparative Effects of High-Tech Visual Scene Displays and Low-Tech Isolated Picture Symbols on Engagement From Students With Multiple Disabilities

2019 ◽  
Vol 50 (4) ◽  
pp. 693-702 ◽  
Author(s):  
Christine Holyfield ◽  
Sydney Brooks ◽  
Allison Schluterman
Keyword(s):  
Language Learning ◽  
Augmentative And Alternative Communication ◽  
Visual Analysis ◽  
Multiple Disabilities ◽  
Visual Scene ◽  
Future Research ◽  
High Tech ◽  
Single Subject ◽  
Wide Range ◽  
The Difference

Purpose Augmentative and alternative communication (AAC) is an intervention approach that can promote communication and language in children with multiple disabilities who are beginning communicators. While a wide range of AAC technologies are available, little is known about the comparative effects of specific technology options. Given that engagement can be low for beginning communicators with multiple disabilities, the current study provides initial information about the comparative effects of 2 AAC technology options—high-tech visual scene displays (VSDs) and low-tech isolated picture symbols—on engagement. Method Three elementary-age beginning communicators with multiple disabilities participated. The study used a single-subject, alternating treatment design with each technology serving as a condition. Participants interacted with their school speech-language pathologists using each of the 2 technologies across 5 sessions in a block randomized order. Results According to visual analysis and nonoverlap of all pairs calculations, all 3 participants demonstrated more engagement with the high-tech VSDs than the low-tech isolated picture symbols as measured by their seconds of gaze toward each technology option. Despite the difference in engagement observed, there was no clear difference across the 2 conditions in engagement toward the communication partner or use of the AAC. Conclusions Clinicians can consider measuring engagement when evaluating AAC technology options for children with multiple disabilities and should consider evaluating high-tech VSDs as 1 technology option for them. Future research must explore the extent to which differences in engagement to particular AAC technologies result in differences in communication and language learning over time as might be expected.

COMBINATORIAL POLYNOMIALLY COMPUTABLE CHARACTERISTICS OF SUBSTITUTIONS AND THEIR PROPERTIES

2020 ◽  
Vol 7 (2) ◽  
pp. 34-41
Author(s):  
VLADIMIR NIKONOV ◽  
◽  
ANTON ZOBOV ◽  
Keyword(s):  
Mathematical Expectation ◽  
Point Of View ◽  
Small Range ◽  
Computational Point ◽  
Wide Range ◽  
Bijective Function ◽  
The Difference ◽  
Element Base ◽  
Selection Of

The construction and selection of a suitable bijective function, that is, substitution, is now becoming an important applied task, particularly for building block encryption systems. Many articles have suggested using different approaches to determining the quality of substitution, but most of them are highly computationally complex. The solution of this problem will significantly expand the range of methods for constructing and analyzing scheme in information protection systems. The purpose of research is to find easily measurable characteristics of substitutions, allowing to evaluate their quality, and also measures of the proximity of a particular substitutions to a random one, or its distance from it. For this purpose, several characteristics were proposed in this work: difference and polynomial, and their mathematical expectation was found, as well as variance for the difference characteristic. This allows us to make a conclusion about its quality by comparing the result of calculating the characteristic for a particular substitution with the calculated mathematical expectation. From a computational point of view, the thesises of the article are of exceptional interest due to the simplicity of the algorithm for quantifying the quality of bijective function substitutions. By its nature, the operation of calculating the difference characteristic carries out a simple summation of integer terms in a fixed and small range. Such an operation, both in the modern and in the prospective element base, is embedded in the logic of a wide range of functional elements, especially when implementing computational actions in the optical range, or on other carriers related to the field of nanotechnology.

Generalized Heterodyne Configurations for Photo-induced Force Microscopy

2019 ◽  
Author(s):  
Le Wang ◽  
Devon Jakob ◽  
Haomin Wang ◽  
Alexis Apostolos ◽  
Marcos M. Pires ◽  
...  
Keyword(s):  
Spatial Resolution ◽  
Repetition Rate ◽  
Modulation Frequency ◽  
High Harmonic ◽  
Chemical Imaging ◽  
Heterodyne Detection ◽  
Force Microscopy ◽  
Wide Range ◽  
The Difference ◽  
Afm Cantilever

<div>Infrared chemical microscopy through mechanical probing of light-matter interactions by atomic force microscopy (AFM) bypasses the diffraction limit. One increasingly popular technique is photo-induced force microscopy (PiFM), which utilizes the mechanical heterodyne signal detection between cantilever mechanical resonant oscillations and the photo induced force from light-matter interaction. So far, photo induced force microscopy has been operated in only one heterodyne configuration. In this article, we generalize heterodyne configurations of photoinduced force microscopy by introducing two new schemes: harmonic heterodyne detection and sequential heterodyne detection. In harmonic heterodyne detection, the laser repetition rate matches integer fractions of the difference between the two mechanical resonant modes of the AFM cantilever. The high harmonic of the beating from the photothermal expansion mixes with the AFM cantilever oscillation to provide PiFM signal. In sequential heterodyne detection, the combination of the repetition rate of laser pulses and polarization modulation frequency matches the difference between two AFM mechanical modes, leading to detectable PiFM signals. These two generalized heterodyne configurations for photo induced force microscopy deliver new avenues for chemical imaging and broadband spectroscopy at ~10 nm spatial resolution. They are suitable for a wide range of heterogeneous materials across various disciplines: from structured polymer film, polaritonic boron nitride materials, to isolated bacterial peptidoglycan cell walls. The generalized heterodyne configurations introduce flexibility for the implementation of PiFM and related tapping mode AFM-IR, and provide possibilities for additional modulation channel in PiFM for targeted signal extraction with nanoscale spatial resolution.</div>

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