scholarly journals Amputee socks: Sock thickness changes with normal use

2015 ◽  
Vol 40 (3) ◽  
pp. 329-335 ◽  
Author(s):  
John C Cagle ◽  
Krittika J D’Silva ◽  
Brian J Hafner ◽  
Daniel S Harrison ◽  
Joan E Sanders
Keyword(s):  
Standard Deviation ◽  
Direct Measurement ◽  
Study Design ◽  
Clinical Relevance ◽  
Weight Bearing ◽  
Mean Difference ◽  
Initial Thickness ◽  
Reduced Volume ◽  
The Mean ◽  
Over Time

Background: Prosthetic socks are expected to decrease in thickness and have reduced volume accommodation with normal use. It is unknown, however, to what degree they reduce in thickness over time. Objective: The goal of this study was to determine a correlation between the age of a prosthetic sock (defined as the out-of-package time) and the resulting change in thickness under standardized weight-bearing and non-weight-bearing conditions. Study design: Experimental, mechanical assessment. Methods: Used prosthetic socks were donated by donors with transtibial amputation. Sock thickness was measured on a custom instrument under conditions representative of normal use. Stress-thickness response was compared to that of equivalent new socks to quantify the effects of use on sock performance. Results: Sock thickness changed non-linearly over time. On average, socks were 75% ± 17% of their initial thickness after 1 month, while socks older than 1 month were 72% ± 18% of their initial thickness. The elasticity of socks did not change with age. Conclusion: The volume accommodation provided by used socks cannot be reliably predicted by ply or age. Direct measurement of total sock thickness may provide meaningful insight to quantify prosthetic users’ socket fit and guide volume accommodation recommendations. Clinical relevance The mean difference in thickness between 3-ply and 5-ply used socks was equal to the standard deviation of each ply group (0.3mm). Therefore, it is possible that a 3-ply sock worn for as a little as 1 month could have a greater thickness than a 5-ply sock worn for a month.

Testing the Theory in Latin America

2020 ◽  
pp. 121-148
Author(s):  
Nicole Baerg
Keyword(s):  
Latin America ◽  
Standard Deviation ◽  
Developed Countries ◽  
Inflation Expectations ◽  
Theoretical Argument ◽  
Instrumental Variable Analysis ◽  
Economic Output ◽  
Information Precision ◽  
The Mean ◽  
Over Time

This chapter moves from studying developed countries to a sample of countries in Latin America over time. The chapter presents evidence that an increase in the information environment, in terms of its level of precision, exerts an attenuating and significant effect on the mean and standard deviation of forecasters’ inflation expectations, ultimately lowering inflation outcomes. The finding is robust to the inclusion of policy credibility, persistence in inflation, economic output, and month and country effects. When conducting instrumental variable analysis, similarly signed results hold. The main results imply that an increase in information precision helps to lower aggregate levels of inflation and that the channel that this works through is by lowering the weight of prior expectations, as predicted by the theoretical argument. Importantly, the results persist even when considering a sample of countries with relatively variable inflation outcomes and less established (and therefore less credible) economic institutions.

scholarly journals Validity of self-reported weight: a study of urban brazilian adults

1993 ◽  
Vol 27 (4) ◽  
pp. 271-276 ◽  
Author(s):  
Maria I. Schmidt ◽  
Bruce B. Duncan ◽  
Mário Tavares ◽  
Carísi A. Polanczyk ◽  
Lúcia Pellanda ◽  
...  
Keyword(s):  
Body Mass Index ◽  
Standard Deviation ◽  
Body Mass ◽  
Mean Difference ◽  
Obesity Prevalence ◽  
Porto Alegre ◽  
Measured Weight ◽  
Prevalence Of Obesity ◽  
The Mean

In order to evaluate the validity of self-reported weight for use in obesity prevalence surveys, self-reported weight was compared to measured weight for 659 adults living in the Porto Alegre county, RS Brazil in 1986-87, both weights being obtained by a technician in the individual's home on the same visit. The mean difference between self-reported and measured weight was small (-0.06 +/- 3.16 kg; mean +/- standard deviation), and the correlation between reported and measured weight was high (r=0.97). Sixty-two percent of participants reported their weight with an error of < 2 kg, 87% with an error of < 4 kg, and 95% with an error of < 6 kg. Underweight individuals overestimated their weight, while obese individuals underestimated theirs (p<0.05). Men tended to overestimate their weight and women underestimate theirs, this difference between sexes being statistically significant (p=0.04). The overall prevalence of underweight (body mass index < 20) by reported weight was 11%, by measured weight 13%; the overall prevalence of obesity (body mass index > 30) by reported weight was 10%, by measured weight 11%. Thus, the validity of reported weight is acceptable for surveys of the prevalence of ponderosity in similar settings.

The Effects of Lifting Frequency on the Dynamics of Lifting

1995 ◽  
Vol 39 (10) ◽  
pp. 650-654 ◽  
Author(s):  
Gary A. Mirka ◽  
Daniel P. Kelaher
Keyword(s):  
Standard Deviation ◽  
Linear Increase ◽  
Time Dependent ◽  
Lumbar Region ◽  
Non Linear ◽  
Trends Over Time ◽  
The Mean ◽  
Over Time

The goal of this study was to quantify the effects of different lifting frequencies (3, 6 and 9 lifts/minute) at different lifting heights (30 and 60 cm) on the kinematics of the lumbar region. Each of these lifting tasks was performed for twenty minutes. The time dependent traces of the both the mean and standard deviation of sagittal acceleration showed subject dependent trends over time. Averaged across time, the results of this study reveal that there is a non-linear increase in the sagittal acceleration with greater frequency of lifting.

scholarly journals The Effectiveness of Mix Impact Aerobic Gymnastics Exercises With SKJ 2000 On Improvement of Physical Freshness

2021 ◽  
Vol 12 (03) ◽  
pp. 39-44
Author(s):  
Anik Maryani ◽  
Fahmy Fachrezzy ◽  
Ramdan Pelana
Keyword(s):  
Standard Deviation ◽  
Physical Fitness ◽  
Aerobic Exercise ◽  
Standard Error ◽  
Exercise Group ◽  
Mean Value ◽  
Mean Difference ◽  
Final Test ◽  
The Mean ◽  
The Difference

This study aims to determine the effectiveness of the effect of aerobic mix impact and SKJ 2000 version (core exercise) to improve physical fitness in female students. The research was conducted at SMEA YASMA Sudirman Cijantung for 8 weeks with 24 meetings. The method used is an experimental method with a pre and post-test design. The sampling technique was random sampling from a total of 40 grade 1 students and 30 samples were taken. The data collection technique used was a physical fitness test using the Indonesian Physical Fitness Test (TKJI). Hypothesis testing uses the t-test at the significant level (α) 0.05. The results showed that the difference between the mean value of the initial test (x) and the final test (y) in the mixed impact aerobic exercise group was obtained = -6.47; the value of the standard deviation of the difference = 1,2; the standard error value of the mean difference = 0.32; and the value becomes = -20,2. The initial test (x) and the final test (y) in the 2000 version of the Physical Fitness exercise obtained the difference in the mean value is = -5; the value of the standard deviation of the difference = 1.1; the standard error value of the mean difference = 0.29; and the value becomes = -17.24. The final test of the mixed impact aerobic exercise group (x) and the final test of the aerobic exercise group (y) version 2000, obtained the mean value of the variable x = 19.33; variable value y = 17; the standard deviation value x = 1.48; standard deviation of the variable y = 2.31; standard error variable x = 0.4; standard error for the variable y = 0.62; standard error for the mean difference between x and variable = 0.74; Hypothesis test results obtained t observation = 3.15, at 28 degrees of freedom and a significant level (α) 0.05, the value of t table = 2.048 is obtained. The conclusion of the study is that the effect of mix impact aerobic exercise is more effective in improving physical fitness compared to those using the 2000 version of the fitness gymnastics version of aerobic exercise.

Linear regression and correlation

2017 ◽  
Author(s):  
Andrew Gelman ◽  
Deborah Nolan
Keyword(s):  
Standard Deviation ◽  
Linear Regression ◽  
Regression Line ◽  
World Population ◽  
Regression To The Mean ◽  
Straight Line ◽  
The Mean ◽  
Line Fitting ◽  
Single Predictor ◽  
Over Time

This chapter addresses the descriptive treatment of linear regression with a single predictor: straight-line fitting, interpretation of the regression line and standard deviation, the confusing phenomenon of “regression to the mean,” correlation, and conducting regressions on the computer. These concepts are illustrated with student discussions and activities. Many examples are of the sort commonly found in statistics textbooks, but the focus here is on how to work the examples into student-participation activities rather than simply examples to be read or shown on the blackboard. Topics include the following relationships: height and income, height and hand span, world population over time, and exam scores.

Effect of Infrared Analyzer Homogenization Efficiency on Repeatability of Uncorrected Fat A and Fat B Signals

1994 ◽  
Vol 77 (5) ◽  
pp. 1217-1223 ◽  
Author(s):  
Erika B Smith ◽  
David M Barbano ◽  
Joanna M Lynch ◽  
J Richard Fleming
Keyword(s):  
Standard Deviation ◽  
Light Scattering ◽  
Raw Milk ◽  
Mean Difference ◽  
Sample Standard Deviation ◽  
The Mean ◽  
Infrared Analyzer

Abstract Poor repeatability by infrared milk analyzers may be caused by inefficient homogenization as a result of light scattering and the Christiansen effect. The objectives of this study were to identify instruments with good and poor homogenization efficiency and to determine if a difference exists in repeatability performance between instruments with good vs poor homogenization efficiency. Unhomo-genized and homogenized portions of the same milk were tested 20 times consecutively on 22 instruments. An instrument was considered to have poor homogenization efficiency if the mean difference in the uncorrected signal between unhomo-genized and homogenized portions of the same milk was ≥1.43% of the fat test (i.e., ≥0.05% at 3.5% fat). Instruments were evaluated for repeatability by calculating the sample standard deviation and the range of the latter 19 uncorrected readings for un-homogenized and homogenized milks. When repeatability was evaluated as a function of homogenization efficiency, there was a significant (p = 0.001) correlation between poor homogenization efficiency and poor repeatability when testing unho-mogenized milk but not when testing homogenized milk. Improved homogenizer performance within infrared milk analyzers is needed to improve the repeatability of raw milk testing.

Redefining the Neck: A Retrospective Review Utilizing Hyoid Suspension

2018 ◽  
Vol 35 (4) ◽  
pp. 198-204
Author(s):  
Sami A. Nizam ◽  
Rhys Branman
Keyword(s):  
Standard Deviation ◽  
Statistical Significance ◽  
Biomechanical Testing ◽  
Retrospective Chart Review ◽  
Mean Difference ◽  
Control Group ◽  
P Value ◽  
Hyoid Suspension ◽  
The Mean ◽  
Experimental Group

Neck contouring is one of the most frequent reasons patients seek cervicofacial rhytidectomy. But what makes for aesthetically pleasing youthful neck? Ellenbogen and Karlin described 5 criteria in their 1980 landmark publication, including having a cervicomental angle between 105° and 120° and a visible subhyoid depression. Recent advances in neck anatomy have revealed the existence of ligamentous like structures attaching the skin and platysma to the hyoid. These have been termed the hyoplatysmal ligament (HPL) and cervicomental suspensory angle ligament by different authors. This study was undertaken to determine whether surgically reestablishing the above structures utilizing a hyoid suspension technique resulted in statistically significant changes in cervicomental contour. A retrospective chart review was performed from January 2014 to present. After December 2016, the second author began utilizing a hyoid suspension technique where the inter- and subplatysmal fat was resected and the HPL was reestablished surgically (hyoid suspension). Cases before this date served as controls if a similar neck manipulation was performed without reestablishing the HPL. In total, 104 charts were queried, of which, 21 charts fit inclusion criteria to serve as controls and 20 as the experimental group. Before and after profile pictures were then compared for differences in cervicomental angle utilizing commercially available imaging software (Canfield Mirror, Parsippany, New Jersey). An unpaired Student t test was then performed to determine whether this 2 groups differed significantly utilizing a P value of .05 to denote statistical significance. The mean difference between pre- and postoperative cervicomental angle for the control group was 17.38° with a standard deviation of 8.05°. The mean difference between pre and postoperative cervicomental angle for the experimental group was 28.75° with a standard deviation of 15.52°. The resulting 11.37° difference in cervicomental angle between the 2 groups was found to be statistically significant with a P value of .0051. Our cosmetic surgical and anatomical knowledge continues to progress. Brant first described a ligamentous structure that attaches the platysma to the hyoid. Through biomechanical testing, he noted this ligament to be one of the weakest in the face and neck. Thereafter, in 2016 Yousif et al and Le Lourn separately described similar procedures to attach the platysma to the hyoid, in effect reestablishing this ligament. Utilizing one simple surgical maneuver, the hyoid suspension reestablishes the HPL. This surgically creates an acute cervicomental angle, resulting in less platysmal displacement postoperatively, with virtually no addition to surgical time or morbidity.

scholarly journals Glenohumeral Rotational Range of Motion in Collegiate Overhead-Throwing Athletes During an Athletic Season

2009 ◽  
Vol 44 (6) ◽  
pp. 611-616 ◽  
Author(s):  
Priscilla M. Dwelly ◽  
Brady L. Tripp ◽  
Patricia A. Tripp ◽  
Lindsey E. Eberman ◽  
Steven Gorin
Keyword(s):  
Range Of Motion ◽  
Internal Rotation ◽  
Ncaa Division I ◽  
Mean Difference ◽  
Division I ◽  
Shoulder Injuries ◽  
The Mean ◽  
Overhead Throwing ◽  
Division Ii ◽  
Over Time

Abstract Context: Repetitive throwing at high velocities leads to altered range of motion (ROM) in the dominant shoulder compared with the nondominant shoulder in overhead-throwing athletes. Loss of glenohumeral internal rotation (IR), or glenohumeral internal-rotation deficit (GIRD), is associated with shoulder injuries. Therefore, GIRD should be evaluated during the clinical examination of the thrower's shoulder. Objective: To assess glenohumeral ROM in competitive baseball and softball athletes at 3 intervals over the course of an athletic season in order to (1) examine changes in ROM over time and (2) monitor the prevalence of GIRD. Design: Observational, repeated-measures study. Setting: Collegiate athletic training room. Patients or Other Participants: Forty-eight healthy National Collegiate Athletic Association (NCAA) Division I or Division II athletes (age  =  19 ± 1 years, height  =  174 ± 14 cm, mass  =  77.8 ± 18.1 kg; 19 softball, 29 baseball players). Main Outcome Measure(s): We measured glenohumeral IR, external rotation (ER), total arc (ER + IR), and GIRD at 3 times: prefall, prespring, and postspring. We calculated GIRD in 2 ways: as the difference in IR between dominant and nondominant shoulders and as the percentage of the total arc. Results: In the dominant shoulder, ER increased during the season (F2,96  =  17.433, P &lt; .001), but IR remained the same (F2,96  =  1.839, P  =  .17). The total arc in the dominant shoulder increased between time intervals (F2,96  =  14.030, P &lt; .001); the mean difference between prefall and postspring measurements was 9.694° (P &lt; .001), and the mean difference between prefall and postspring measurements was 10.990° (P &lt; .001). In the nondominant shoulder, ER increased over the season (F2,96  =  23.395, P &lt; .001), but IR did not change over the season (F2,96  =  0.087, P  =  .90). The total arc in the nondominant shoulder increased between prefall and prespring measurements and between prefall and postspring measurements (F2,96  =  18.552, P &lt; .001). No changes were noted in GIRD over time. However, more athletes with GIRD were identified with the GIRD (IR difference) calculation in prefall (n  =  6) than in prespring (n  =  1) and postspring (n  =  4) (Cochran Q  =  5.2, P  =  .07). In addition, more athletes with GIRD were identified with the GIRD (% total arc) calculation in postspring (n  =  6) than in prefall (n  =  5) or prespring (n  =  4) (Cochran Q  =  2.6, P  =  .27). Conclusions: Healthy NCAA Division I and Division II athletes did not display changes in glenohumeral IR over an athletic season. However, they gained in ER and total arc during the season in both shoulders. Future researchers should investigate changes over multiple seasons. The 2 methods of calculating GIRD identified different athletes as having GIRD, indicating that additional investigation is warranted to determine the clinical benefits of each method.

scholarly journals Improved information about the vertical location and extent of cloud layers from POLDER3 measurements in the oxygen A band

2013 ◽  
Vol 6 (2) ◽  
pp. 2533-2581 ◽  
Author(s):  
M. Desmons ◽  
N. Ferlay ◽  
F. Parol ◽  
L. Mcharek ◽  
C. Vanbauce
Keyword(s):  
Standard Deviation ◽  
Oxygen Pressure ◽  
Optical Thickness ◽  
Mean Difference ◽  
Vertical Extent ◽  
Satellite Platform ◽  
Cloud Optical Thickness ◽  
The Mean ◽  
The Difference ◽  
The One

Abstract. This paper describes new advances in the exploitation of oxygen A band measurements from POLDER3 sensor aboard PARASOL, satellite platform within the A-Train. These developments result from a better account of the dependence of POLDER oxygen parameters to cloud optical thickness τ and to the scene's geometrical conditions, but also and more importantly from the finer understanding of the sensitivity of these parameters to cloud vertical extent. This sensitivity is made possible thanks to the multidirectional character of POLDER measurements. In the case of monolayer clouds that represent most of cloudy conditions, new oxygen parameters are obtained and calibrated from POLDER3 data colocalized with the measurements of the two active sensors of the A-Train, CALIOP/CALIPSO and CPR/CloudSat. From a parameterization that is (μs, τ) dependent, with μs the cosine of the solar zenith angle, a cloud top oxygen pressure (CTOP) and a cloud middle oxygen pressure (CMOP) are obtained which are estimates of actual cloud top and middle pressures. The performance of CTOP and CMOP are presented for the most numerous ISCCP cases in 2008. The coefficient of the correlation between CMOP and the actual cloud middle pressure is 0.81 for cirrostratus, 0.79 for stratocumulus, 0.75 for deep convective clouds. The coefficient of the correlation between CTOP and the actual cloud top pressure is 0.75, 0.73, and 0.79 for the same cloud types respectively. The score obtained by CTOP, defined as the confidence in the retrieval for a particular range of infered value and for a given error, is higher than the one of MODIS CTP. For liquid and ice clouds, the score reaches 50 and 70% respectively for bin value of CTP superior in numbers and accepted errors of 30 and 50 hPa. From the difference between CTOP and CMOP, a first estimate of the cloud vertical extent H is possible. Then, the correlation between the angular standard deviation of POLDER oxygen pressure σPO2 and the cloud vertical extent is described in detail in the case of liquid clouds. The correlation is shown to be spatially and temporally robust, excepted for clouds above land during winter months. The study of the correlation's dependence to cloud optical thickness and to the scene's geometrical conditions leads to parameterizations which provide a second way for retrieving H for this type of clouds. For liquid water clouds above ocean in 2008, the mean difference between the actual cloud vertical extent and the one retrieved from σPO2 (from the pressure difference) is 5 m (−12 m). The standard deviation of the mean difference is close to 1000 m for the two methods. The score of 50% confidence for the retrieval of H corresponds to an error of 20 and 40% for ice and liquid clouds respectively over ocean. These promising results need to be validated outside of the CALIPSO/CloudSat track.

scholarly journals PEMBERDAYAAN SISWA SEBAGAI KADER KESEHATAN DALAM PROGRAM EDUKASI KESEHATAN REPRODUKSI REMAJA DI SMP SWASTA MEDAN

2018 ◽  
Vol 3 (2) ◽  
pp. 27
Author(s):  
Nur Asnah Sitohang ◽  
Diah Lestari Nasution ◽  
Cut Adeya Adella
Keyword(s):  
High School ◽  
Sexual Behavior ◽  
Standard Deviation ◽  
Reproductive Health ◽  
Risky Sexual Behavior ◽  
Student Attitudes ◽  
Junior High ◽  
Mean Difference ◽  
The Mean ◽  
Adolescent Reproductive Health

Adolescent reproductive and sexuality health in Indonesia is still low, this can be seen from the many cases of pregnancy out of wedlock, violence during courtship and abortion with high-risk drugs. The understanding of adolescents about reproductive health is the provision of adolescents in healthy and responsible behavior. But not all teenagers get information about reproductive health. This limitation of knowledge and understanding can bring teenagers towards risky behavior. This is a lack of information about sexuality and reproduction. Cadres health has a big role in realizing the optimal level of community health. Community service is carried out in two (2) junior high schools, namely Dharma Pancasila Private Junior High School (260 students and 21 cadres trained) and Al-Fhatiyan Private Middle School Medan (199 students and cadres trained by 16 students). The method used is by: 1. counseling with material on adolescent reproductive health; 2. cadre training; 3. Cadre mentoring. Evaluation of program success: pre test and post test cadres and student participants. Based on the results of the questionnaires distributed to students, the majority of data was 13 years old (47.5%), male sex (54%), high school parents education (62%) and entrepreneurial work (96.6%). The results of the dependent test obtained data, average knowledge before health education 26.23 and after health education39.58. The mean difference is 13,349 and the standard deviation is 3,911 and 95% CI 13,707-12,990. Based on the results of statistical tests obtained P = 0.001, it can be concluded that there is an influence of adolescent reproductive health cadres on student knowledge. For attitudes obtained data on average attitudes before counseling 27.57 and after counseling 39.58. The mean difference is 13,349 and the standard deviation is 3,802 and 95% CI 12,362 - 11,664. P value = 0.001 it can be concluded that there is an influence of adolescent reproductive health cadres on student attitudes. This PKM activity is useful in increasing knowledge and attitudes towards adolescent reproductive health. With increased knowledge of the behavior of adolescents to risky sexual behavior, and if the attitudes of adolescents towards sexual behavior are good, it is expected that sexually well and adolescents are expected to be responsible for their reproductive healthKeywords: cadres, education, health, reproduction, adolescents

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