scholarly journals A Review of Validation Methods for the Intracranial Response of FEHM to Blunt Impacts

2020 ◽  
Vol 10 (20) ◽  
pp. 7227
Author(s):  
K. McGill ◽  
F. Teixeira-Dias ◽  
A. Callanan
Keyword(s):  
Experimental Data ◽  
Best Practice ◽  
Human Subjects ◽  
Analytical Techniques ◽  
Head Motion ◽  
Validation Process ◽  
Factors Affecting ◽  
Strain Responses ◽  
Finite Element Head Models ◽  
Point Of Reference

The following is a review of the processes currently employed when validating the intracranial response of Finite Element Head Models (FEHM) against blunt impacts. The authors aim to collate existing validation tools, their applications and findings on their effectiveness to aid researchers in the validation of future FEHM and potential efforts in improving procedures. In this vain, publications providing experimental data on the intracranial pressure, relative brain displacement and brain strain responses to impacts in human subjects are surveyed and key data are summarised. This includes cases that have previously been used in FEHM validation and alternatives with similar potential uses. The processes employed to replicate impact conditions and the resulting head motion are reviewed, as are the analytical techniques used to judge the validity of the models. Finally, publications exploring the validation process and factors affecting it are critically discussed. Reviewing FEHM validation in this way highlights the lack of a single best practice, or an obvious solution to create one using the tools currently available. There is clear scope to improve the validation process of FEHM, and the data available to achieve this. By collecting information from existing publications, it is hoped this review can help guide such developments and provide a point of reference for researchers looking to validate or investigate FEHM in the future, enabling them to make informed choices about the simulation of impacts, how they are generated numerically and the factors considered during output assessment, whilst being aware of potential limitations in the process.

scholarly journals Electrodermal Response in Gaming

2011 ◽  
Vol 2011 ◽  
pp. 1-14 ◽  
Author(s):  
J. Christopher Westland
Keyword(s):  
Computer Games ◽  
Emotional Response ◽  
Human Subjects ◽  
Skin Resistance ◽  
The Body ◽  
Electrodermal Response ◽  
Factors Affecting ◽  
Measuring Devices ◽  
History Of ◽  
Body Resistance

Steady improvements in technologies that measure human emotional response offer new possibilities for making computer games more immersive. This paper reviews the history of designs a particular branch of affective technologies that acquire electrodermal response readings from human subjects. Electrodermal response meters have gone through continual improvements to better measure these nervous responses, but still fall short of the capabilities of today's technology. Electrodermal response traditionally have been labor intensive. Protocols and transcription of subject responses were recorded on separate documents, forcing constant shifts of attention between scripts, electrodermal measuring devices and of observations and subject responses. These problems can be resolved by collecting more information and integrating it in a computer interface that is, by adding relevant sensors in addition to the basic electrodermal resistance reading to untangle (1) body resistance; (2) skin resistance; (3) grip movements; other (4) factors affecting the neural processing for regulation of the body. A device that solves these problems is presented and discussed. It is argued that the electrodermal response datastreams can be enriched through the use of added sensors and a digital acquisition and processing of information, which should further experimentation and use of the technology.

scholarly journals Tensile Testing with Cyclic Strain Holding to Analyze Dynamic Recrystallization of Pure Lead

2014 ◽  
Vol 2014 ◽  
pp. 1-8
Author(s):  
Mayu Muramatsu ◽  
Motomichi Koyama ◽  
Ikumu Watanabe
Keyword(s):  
Dynamic Recrystallization ◽  
Tensile Testing ◽  
Cyclic Strain ◽  
Tensile Tests ◽  
Pure Lead ◽  
Factors Affecting ◽  
Before And After ◽  
Dynamic Recrystallization Behavior ◽  
The Difference ◽  
Strain Responses

We analyzed the dynamic recrystallization of pure lead by tensile testing with cyclic strain holding at room temperature. The specimens were held at an identical strain and subsequently reloaded, providing the strength before and after the strain holding process. The difference in strength enables factors affecting dynamic recrystallization behavior to be analyzed through mechanical testing. For instance, the effects of strain rate on dynamic recrystallization were analyzed by comparing the results obtained from tensile tests with and without strain holding. This experimental technique demonstrated some parts of contribution of elastic strain, dynamic recovery, dynamic recrystallization, and necking to stress-strain responses.

scholarly journals Factors Affecting the Severity of Placental Abruption in Pregnant Vehicle Drivers: Analysis with a Novel Finite Element Model

Healthcare ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 27
Author(s):  
Katsunori Tanaka ◽  
Yasuki Motozawa ◽  
Kentaro Takahashi ◽  
Tetsuo Maki ◽  
Masahito Hitosugi
Keyword(s):  
Finite Element ◽  
Pregnant Woman ◽  
Finite Element Model ◽  
Placental Abruption ◽  
Motor Vehicle ◽  
Human Subjects ◽  
Element Model ◽  
Collision Velocity ◽  
Vehicle Collisions ◽  
Factors Affecting

We clarified factors affecting the severity of placental abruption in motor vehicle collisions by quantitively analyzing the area of placental abruption in a numerical simulation of an unrestrained pregnant vehicle driver at collision velocities of 3 and 6 m/s. For the simulation, we constructed a novel finite element model of a small 30-week pregnant woman, which was validated anthropometrically using computed tomography data and biomechanically using previous examinations of post-mortem human subjects. In the simulation, stress in the elements of the utero–placental interface was computed, and those elements exceeding a failure criterion were considered to be abrupted. It was found that a doubling of the collision velocity increased the area of placental abruption 10-fold, and the abruption area was approximately 20% for a collision velocity of 6 m/s, which is lower than the speed limit for general roads. This result implies that even low-speed vehicle collisions have negative maternal and fetal outcomes owing to placental abruption without a seatbelt restraint. Additionally, contact to the abdomen, 30 mm below the umbilicus, led to a larger placental abruption area than contact at the umbilicus level when the placenta was located at the uterus fundus. The results support that a reduction in the collision speed and seatbelt restraint at a suitable position are important to decrease the placental abruption area and therefore protect a pregnant woman and her fetus in a motor vehicle collision.

scholarly journals Factors affecting removal of bacterial pathogens from healthcare surfaces during dynamic wiping

2018 ◽  
Vol 89 (4) ◽  
pp. 580-589 ◽  
Author(s):  
NWM Edwards ◽  
EL Best ◽  
P Goswami ◽  
MH Wilcox ◽  
SJ Russell
Keyword(s):  
Removal Efficiency ◽  
Surface Density ◽  
Pathogenic Bacteria ◽  
Best Practice ◽  
Regenerated Cellulose ◽  
Extrinsic Factors ◽  
Factors Affecting ◽  
E Coli ◽  
Liquid Removal ◽  
Fabric Surface

Wiping of surfaces contaminated with pathogenic bacteria is a key strategy for combating the transmission of healthcare associated infections. It is essential to understand the extent to which removal of bacteria is modulated by fiber properties, biocidal liquid impregnation and applied hand pressure. The influence of intrinsic and extrinsic factors on the removal efficiencies of pathogenic bacteria was studied. Nonwoven wipes made of either hydrophobic (polypropylene) or hygroscopic (lyocell) fibers were manufactured and dynamic removal efficiency of bacteria studied. The single most important parameter affecting bacterial removal efficiency was impregnation with biocidal liquid ( p < 0.05). For inherently hygroscopic 100% regenerated cellulose (lyocell) wipes impregnated with biocidal liquid, removal of E. coli, S. aureus and E. faecalis improved by increasing the fabric surface density and wiping pressure to their maximal values – 150 g.m–2 and 13.80 kN.m–2, respectively. For inherently hydrophobic 100% polypropylene nonwoven wipes, the same conditions maximized the removal efficiency of S. aureus, but for E. coli and E. faecalis a reduction in the wiping pressure to 4.68 kN.m–2 was required. Best practice involves the use of higher surface density wipes (150 g.m–2) containing regenerated cellulose fibers loaded with liquid biocide, and applied with the greatest possible wiping pressure.

Using Exponential Cubic Splines to Predict Low Temperature Behavior of Elastomeric Materials

1994 ◽  
Author(s):  
Terry E. Shoup ◽  
George R. Fegan
Keyword(s):  
Experimental Data ◽  
Elastic Modulus ◽  
Low Temperatures ◽  
Analytical Techniques ◽  
High Sensitivity ◽  
Considerable Difficulty ◽  
Spline Curves ◽  
Different Types ◽  
Elastomeric Materials ◽  
Energy Absorbing

Abstract Because of their desirable elastic and energy absorbing properties, elastomeric materials have been widely used as shock mounts and pressure seals. The high sensitivity of the elastic modulus of these materials to changes in temperature has been a source of considerable difficulty to the development of robust design methods based on analytical techniques. This paper presents a simple analytical method for predicting the elastic modulus for a group of five different types of elastomers when used at low temperatures. The method is based on the application of exponential cubic spline curves to smooth experimental data. The method is applied to experimental data from the literature to illustrate its usefulness.

Entrepreneurial or Not?

2016 ◽  
pp. 110-133
Author(s):  
Chitra Buckley
Keyword(s):  
Conceptual Framework ◽  
Business Model ◽  
Early Phase ◽  
Best Practice ◽  
Business Models ◽  
Survival Strategies ◽  
Growth Strategies ◽  
Model Concept ◽  
Micro Enterprises ◽  
Point Of Reference

UK fashion micro-enterprises, often founded by creative individuals, need to be entrepreneurially oriented and develop a business model that sustains their growth during the critical early phase. Literature on this phase offers guidance in best practice and survival strategies for the operational challenges that emerge, however the business models that sustain enterprise development and provide the blueprint for growth strategies have not been examined. This chapter explores how micro-enterprises integrate entrepreneurial actions into their business models. By applying literature on best practice in fashion designer businesses and entrepreneurial orientation (EO) to the business model concept, a conceptual framework is developed and serves as a point of reference to analyse the current business models of five micro-enterprises. The study finds that business models in this segment of the fashion sector are asymmetrical and EO emerges in some components of the business model and not others.

scholarly journals Poorly recognized age-related downward deviation of the inguinal ligament

2016 ◽  
Vol 4 ◽  
pp. 205031211667556 ◽  
Author(s):  
Yassir Nawaz ◽  
Mihir Barvalia ◽  
Gurinder Rana ◽  
M Zain Khakwani ◽  
Khizr Azim ◽  
...  
Keyword(s):  
Human Subjects ◽  
A Priori ◽  
Linear Regression Analysis ◽  
Age Groups ◽  
Vascular Complications ◽  
Multiple Linear Regression Analysis ◽  
Inguinal Ligament ◽  
Mean Deviation ◽  
Factors Affecting ◽  
Age Related

Objective: To determine factors affecting actual inguinal ligament course in live human subjects. Introduction and hypothesis: Although the expected inguinal ligament course is supposedly a straight line extending from anterior superior iliac spine to pubic tubercle, the actual inguinal ligament course is frequently depicted a priori by a downward bowing dotted line. There are no studies in a live subject supporting this assumption. We hypothesized this assumption is indeed valid and is related to among other factors a lifelong effect of gravity and lax abdominal musculature on the inguinal ligament course. Methods: We retrospectively reviewed 54 consecutive computed tomography scans of the abdomen and pelvis randomly distributed across all age groups. Actual inguinal ligament course was visualized by reconstructing images using Terracon software. Vertical distance from the lowest point of actual inguinal ligament course to the expected inguinal ligament course was measured. We used multiple linear regression analysis to study the correlation between degree of inguinal ligament deviation and several variables. Results: Actual inguinal ligament course was below the expected inguinal ligament course in 52 of 54 patients. The mean deviation was 8.2 ± 5.9 mm. Advanced age was significantly associated with greater downward bowing of the inguinal ligament (p = 0.001). Conclusion: Actual inguinal ligament course is often well below the expected inguinal ligament course; this downward bowing of the inguinal ligament is especially pronounced with advancing age. Operators need to be mindful as this downward bowing can lead to supra-inguinal sticks causing vascular complications.

scholarly journals Empowering thyroid hormone research in human subjects using OMICs technologies

2018 ◽  
Vol 238 (1) ◽  
pp. R13-R29 ◽  
Author(s):  
Maik Pietzner ◽  
Tim Kacprowski ◽  
Nele Friedrich
Keyword(s):  
Thyroid Hormone ◽  
Thyroid Hormones ◽  
Target Genes ◽  
Human Subjects ◽  
Experimental Studies ◽  
Analytical Techniques ◽  
Population Based ◽  
Whole Body ◽  
Hormone Research ◽  
Whole Body Metabolism

OMICs subsume different physiological layers including the genome, transcriptome, proteome and metabolome. Recent advances in analytical techniques allow for the exhaustive determination of biomolecules in all OMICs levels from less invasive human specimens such as blood and urine. Investigating OMICs in deeply characterized population-based or experimental studies has led to seminal improvement of our understanding of genetic determinants of thyroid function, identified putative thyroid hormone target genes and thyroid hormone-induced shifts in the plasma protein and metabolite content. Consequently, plasma biomolecules have been suggested as surrogates of tissue-specific action of thyroid hormones. This review provides a brief introduction to OMICs in thyroid research with a particular focus on metabolomics studies in humans elucidating the important role of thyroid hormones for whole body metabolism in adults.

BLOOD AMINO ACID STUDIES: IV. SOME FACTORS AFFECTING PLASMA AMINO ACID LEVELS IN HUMAN SUBJECTS

1963 ◽  
Vol 41 (1) ◽  
pp. 191-199 ◽  
Author(s):  
J. M. McLaughlan ◽  
F. J. Noel ◽  
A. B. Morrison ◽  
J. A. Campbell
Keyword(s):  
Amino Acid ◽  
Human Subjects ◽  
Plasma Amino Acid ◽  
Small Samples ◽  
Breakfast Cereal ◽  
Specific Amino Acid ◽  
Factors Affecting ◽  
Practical Procedure ◽  
Plasma Amino Acid Response ◽  
Amino Acid Levels

Free lysine, methionine, threonine, and tryptophan were determined in small samples of blood obtained by finger punch from human subjects. The levels of the four amino acids rose rapidly after the subjects consumed protein as baked halibut; the extent and duration of the increases were roughly proportional to the amount of protein eaten and to the amino acid composition of the protein. The increases of free methionine and threonine in plasma were somewhat less when butter was taken with fish but starch (as potato) or sucrose did not affect the values. Other foods tested at the 19.0-g level of protein included egg, a commercial breakfast cereal, and the same cereal plus milk. In general the increase or decrease of each amino acid tested was related to the amount of that amino acid in the test food. The plasma amino acid (PAA) ratio of Longenecker and Hause was calculated for each food and was useful in evaluating the increase or decrease of each specific amino acid. The present work appears to offer a practical procedure for studying the plasma amino acid response of groups of human subjects to variations in dietary protein.

scholarly journals Engineering Functionalized Chitosan-Based Sorbent Material: Characterization and Sorption of Toxic Elements

2019 ◽  
Vol 9 (23) ◽  
pp. 5138 ◽  
Author(s):  
Adnan Khan ◽  
Nisar Ali ◽  
Muhammad Bilal ◽  
Sumeet Malik ◽  
Syed Badshah ◽  
...  
Keyword(s):  
Experimental Data ◽  
Sorption Isotherms ◽  
Analytical Techniques ◽  
Aqueous Environment ◽  
X Ray Diffraction ◽  
Sorption Data ◽  
Regression Methods ◽  
Sorbent Material ◽  
Lead And Cadmium ◽  
Cadmium And Lead

The present study reports the engineering of functionalized chitosan (CH)-based biosorbent material. Herein, a two-step reaction was performed to chemically modify the CH using 1,4-bis(3-aminopropyl) piperazine to incorporate nitrogen basic centers for cations sorption from the aqueous environment. The resultant functionalized chitosan-based sorbent material was designated as CH-ANP and characterized using various analytical techniques, including elemental analysis, Fourier-transform infrared spectroscopy (FTIR), 13C NMR (in solid-state), X-ray diffraction, and thermal analysis. Then, the newly engineered CH-ANP was employed for the removal of copper, lead, and cadmium in the aqueous medium. Langmuir sorption isotherm analysis revealed that the highest sorption abilities achieved were 2.82, 1.96, and 1.60 mmol g−1 for copper, cadmium, and lead, respectively. Linear and nonlinear regression methods were deployed on the sorption data to study the behavior of the Langmuir, the Freundlich, and the Temkin sorption isotherms. Among the four different forms, the Langmuir isotherm type 1 fit well to the experimental data as compared to the other models. It also showed the lowest values of error, and a higher correlation coefficient than the Freundlich and Temkin models; thus it was the best fit with the experimental data compared to the latter two models. In conclusion, the findings suggest that chemically modified novel materials with enhanced Lewis basic centers are useful and promising candidates for the sorption of various toxic cations in aqueous solution.

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