bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparison of Munsell® color chart assessments with primary schoolchildren's self‐reported skin color
Authors: Wright C. Y. , Reeder A. I. , Gray A. R. , Hammond V. A. 
Published: March 2015

BackgroundSkin color is related to human health outcomes, including the risks of skin cancer and vitamin D insufficiency. Self‐perceptions of skin color may influence health behaviours, including the adoption of practices protective against harmful solar ultraviolet radiation levels. Misperception of personal risk may have negative health implications. The aim of this study is to determine whether Munsell® color chart assessments align with child self‐reported skin color.MethodsTwo‐trained investigators, with assessed color acuity, visually classified student inner upper arm constitutive skin color. The Munsell® classifications obtained were converted to Individual Typology Angle (ITA) values and respective Del Bino skin color categories after spectrocolorimeter measurements based on published values/data. As part of a written questionnaire on sun protection knowledge, attitudes, and behaviours, self‐completed in class time, students classified their end of winter skin color. Student self‐reports were compared with the ITA‐based Del Bino classifications. A total of 477 New Zealand primary students attending 27 randomly selected schools from five geographic regions. The main measures were self‐reported skin color and visually observed skin color.ResultsA monotonic association was observed between the distribution of spectrophotometer ITA scores obtained for Munsell® tiles and child self‐reports of skin color, providing some evidence for the validity of self‐report among New Zealand primary school children, although the lighter colored ITA defined groups were most numerous in this study sample. Statistically significant differences in ITA scores were found by ethnicity, self‐reported skin color, and geographic residence (P < 0.001). Certain Munsell® color tiles were frequently selected as providing a best match to skin color.ConclusionAssessment using Munsell® color charts was simple, inexpensive, and practical for field use and acceptable to children. The results suggest that this method may prove useful for making comparisons with other studies using visual tools to assess skin color. Alignment between the ITA distribution derived from the Munsell® assessment and child skin color self‐reports could probably be improved, particularly with the addition of another ‘light’/’white’ color category in the self‐report instrument.
Near infrared and skin impedance spectroscopy – a possible support in the diagnostic process of skin tumours in primary health care
Authors: Hägerlind E. , Falk M. , Löfstedt T. , Lindholm‐Sethson B. , Bodén I. 
Published: March 2015

Background/purposeThe global incidence of skin cancer has increased drastically in recent decades, especially in Australia and Northern Europe. Early detection is crucial for good prognosis and high survival rates. In general, primary care physicians have considerably lower sensitivity and specificity rates for detection of skin cancer, compared to dermatologists. A probable main reason for this is that current diagnostic tools are subjective in nature, and therefore diagnostic skills highly depend on experience. Illustratively, in Sweden, approximately 155 500 benign skin lesions are excised unnecessarily every year. An objective instrument, added to the clinical examination, might improve the diagnostic accuracy, and thus promote earlier detection of malignant skin tumours, as well as reduce medical costs associated with unnecessary biopsies and excisions. The general aim of this study was to investigate the usefulness of the combination of near infrared (NIR) and skin impedance spectroscopy as a supportive tool in the diagnosis and evaluation of skin tumours in primary health care.MethodsNear infrared and skin impedance data were collected by performing measurements on suspect malignant, premalignant and benign tumours in the skin of patients seeking primary health care for skin tumour evaluation. The obtained data were analysed using multivariate analysis and compared with the diagnosis received by the conventional diagnostic process.ResultsThe observed sensitivity and specificity rates were both 100%, when discriminating malignant and premalignant skin tumours from benign skin tumours, and the observed sensitivity and specificity for separating malignant skin tumours from premalignant and benign skin tumours were also 100%, respectively.ConclusionThe results of this study indicate that the NIR and skin impedance spectroscopy may be a useful supportive tool for the general practitioner in the diagnosis and evaluation of skin tumours in primary health care, as a complement to the visual assessment.
Deranged sodium to sudden death
Authors: Clancy Colleen E. , Chen‐Izu Ye , Bers Donald M. , Belardinelli Luiz , Boyden Penelope A. , Csernoch Laszlo , Despa Sanda , Fermini Bernard , Hool Livia C. , Izu Leighton , Kass Robert S. , Lederer W. Jonathan , Louch William E. , Maack Christoph , Matiazzi Alicia , Qu Zhilin , Rajamani Sridharan , Rippinger Crystal M. , Sejersted Ole M. , O'Rourke Brian , Weiss James N. , Varró András , Zaza Antonio 
Published: March 2015

AbstractIn February 2014, a group of scientists convened as part of the University of California Davis Cardiovascular Symposium to bring together experimental and mathematical modelling perspectives and discuss points of consensus and controversy on the topic of sodium in the heart. This paper summarizes the topics of presentation and discussion from the symposium, with a focus on the role of aberrant sodium channels and abnormal sodium homeostasis in cardiac arrhythmias and pharmacotherapy from the subcellular scale to the whole heart. Two following papers focus on Na+ channel structure, function and regulation, and Na+/Ca2+ exchange and Na+/K+ ATPase. The UC Davis Cardiovascular Symposium is a biannual event that aims to bring together leading experts in subfields of cardiovascular biomedicine to focus on topics of importance to the field. The focus on Na+ in the 2014 symposium stemmed from the multitude of recent studies that point to the importance of maintaining Na+ homeostasis in the heart, as disruption of homeostatic processes are increasingly identified in cardiac disease states. Understanding how disruption in cardiac Na+‐based processes leads to derangement in multiple cardiac components at the level of the cell and to then connect these perturbations to emergent behaviour in the heart to cause disease is a critical area of research. The ubiquity of disruption of Na+ channels and Na+ homeostasis in cardiac disorders of excitability and mechanics emphasizes the importance of a fundamental understanding of the associated mechanisms and disease processes to ultimately reveal new targets for human therapy.
Research Articles in Peer-Reviewed Journals from Past BIOMATH conferences
Authors: Ivanov Tihomir 
Published: March 2015

The В past biomathematical conferences in Sofia (Biomath-1995, Destobio-1997, MMSC-2009, Biomath-2011, Biomath-2012, Biomath-2013, Biomath-2014) resulted in a total number of 179 original research journal articles, as follows: 4 articles in J.UCS, 34 articles in Mathematical Biosciences, 59 articles in В Computers & Mathematics with Applications, 12 articles in Serdica Journal of Computing, В 14 articles in B&BE and 56 articles in journal BIOMATH. A list of titles of these articles follows.
Contact Mechanics Model of Lateral Resurfacing Elbow With Inclusion of Rough Surfaces
Authors: Hodaei Mohammad , Farhang Kambiz 
Published: March 2015

The study of joint contact mechanics to better understanding of all processes leading to cartilage degradation is very necessary. Elbow replacement will be the only option if both inner and outer components of the elbow have severe arthritis, or usually rheumatoid arthritis. It may also be recommended if there is osteoarthritis which makes the elbow stiff and painful, or a severe fracture of the elbow. Recently the operation known as Lateral resurfacing elbow replacement has been developed and introduced in hospitals. This operation has been designed for those people whose disease in the elbow involves mainly the outer compartment of the joint. The components are made from the metal and polyethylene and are fixed to the bones. An improper design of implants can lead to toxicity for patients caused by excessive amount of metal debris.
The purpose of this paper is to investigate the effect of roughness in Lateral resurfacing elbow implants. This paper develops a contact model to treat the interaction of the new surfaces fixed to the top of radius and humeral. The contact model describes the interaction of implant rough surfaces including both elastic and plastic deformations. In the model, surfaces are investigated as macroscopically conforming semi-spheres containing micron-scale roughness. The derived equations relate contact force on the implant and the minimum mean surface separation of the rough surfaces. Based on the distribution of asperity heights, the force is expressed using statistical integral function of asperity heights over the possible region of interaction of the roughness of the implant surfaces. Closed-form approximate equation relating contact force and minimum separation is used to obtain energy loss per cycle in a load-unload sequence applied to the implant.
Computer Simulation and Modelling of Passive Humidification Device Cavity for Intensive Care Patient Medical Applications
Authors: Shafik Mahmoud , Lechevretel Anne 
Published: March 2015

This paper presents the research that has been undertaken into the passive humidification device cavity airflow structures and patterns. This was aiming to improve the device airflow, Heat and Moisture Exchange (HME) materials performance, for a greater patient care. However the objectives were to assist in understanding the optimal cavity structural geometries, generating improved airflow patterns over target HME material structures and consequently leading to improved heat and moisture exchange properties.
Airflow studies of the device have been undertaken using the Computational Fluid Dynamics (CFD) interface of the ANSYS. The CFD package enables analysis of fluid flow and heat transfer. This paper presents the results of the CFD simulations carried out on different passive humidification device cavity designs and materials arrangements. An optimised design leading to enhanced airflow structures and patterns, heat and moisture properties of the device is also presented in this paper.
Analysis of Performances of a Semi-Active Suspension Implemented on a Landing Gear
Authors: Ocaña Marta I. , Novillo Eva , Morante Esteban , Chamorro Eduardo 
Published: March 2015

Semi-active suspensions are able to adapt their behavior to the specific necessities of each operation phase of the vehicle. Their application in the aerospace industry is very attractive, specifically in landing gear actuators. However, according to Ref. [1], no examples of commercial use of this technology in this industry are reported in recent reviews of the state of the art.
In this paper, the real capabilities of a magneto-rheological semi-active suspension implemented on an UAV nose landing gear designed and manufactured by CESA are introduced by the analysis of the performances obtained by test when it is submitted to quasi-static and dynamic working conditions.
Transient Two-Phase Effects in an Aeroengine Bearing Chamber Scavenge Test Rig
Authors: Chandra Budi , Simmons Kathy 
Published: March 2015

Aeroengine bearing chambers typically contain bearings, seals, shafts and static parts. Oil is introduced for lubrication and cooling and this creates a two phase flow environment that may contain droplets, mist, film, ligaments, froth or foam and liquid pools. Efficient and effective liquid removal from a bearing chamber is a functional requirement and in recent years the University of Nottingham Technology Centre in Gas Turbine Transmission Systems has been conducting an experimental and computational research program one strand of which is investigating bearing chamber off-take flows. Initial investigations focussed on a chamber where there was a relatively deep pocket for oil collection below the chamber [1, 2]. In more recent studies Chandra et al have investigated a shallower geometry [3]. In both sets of studies, chamber residence volume and wall film thickness data have been obtained for a range of shaft speeds, scavenge ratios and liquid supply rates. Two methods of introducing liquid to the chamber have been used: a film generator that puts liquid directly onto the chamber wall and a droplet inlet system that distributes droplets from the rotating shaft.
During some of the previous investigations, visual data relating to the two phase flow in the outlet pipe immediately below the chamber was gathered together with data from pressure transducers one located in this pipe and one on the chamber itself. It has been observed that for some parameter combinations the chamber flow is gravity dominated whereas for others (typically at higher shaft speeds) the flow is shear dominated. During transition between regimes a pressure spike on the pipe pressure transducer is observed and this may be linked to a change in two phase flow regime within the outlet pipe. A study by Baker et al [4] on transient effects in gas-liquid separation has shown pressure spikes during transitions to new equilibrium conditions for two-phase pipe flow where the gas flow rate is suddenly increased.
In this paper outlet visualisation, chamber visualisation and pressure data are combined and conclusions are drawn relating to the parameters controlling whether shear or gravity dominate. The effect of the chamber flow regime on the outlet flow regime is assessed and presented. An implication of the analysis is that during transitional conditions a bearing chamber may contain a different quantity of liquid than in steady state conditions.
Research on Self-Loosening Mechanism of Bolted Joints Under Transversal Vibration
Authors: Wang Wei , Wang Qingli , Zheng Shuai , Liu Xiaowei , Liu Haiping 
Published: March 2015

Bolted joints are widely used in the auto industry, energy field and Construction, and so on. Due to the wide use of the bolted joints, the degradation of bolts has significant effect on the performance of a whole machine. Under transversal vibration, the self-loosening of bolted joints, which is the biggest form of failure ranked only second to fatigue failure [1], will happen, due to the cyclic shear load. This paper is to study the mechanism of bolted joints’ self-loosening.
Aiming at analyzing the self-loosening mechanism of bolted joints under vibration, a three dimensional FEA model of bolted joints, which had taken thread into consideration, was built with the application of APDL, and the preload was applied on the bolted joints by dropping temperature, then FEA transient analysis of the bolted joints under transverse cyclic excitation was conducted. Effect of transverse cyclic excitation’s amplitude, initial preload, thread and bearing friction coefficients, the joints’ surface friction coefficient, the thread pitch and the hole clearance on self-loosening was investigated. The results show that the complete thread slip occurs prior to the complete bearing surface slip under transverse vibration; the smaller amplitude, the smaller thread pitch and the smaller hole clearance is, and the greater initial preload, thread and bearing friction coefficients are, the more difficult self-loosening is to happen; the joints’ surface friction coefficient has little relationship with self-loosening, however, the larger joints’ surface friction coefficient makes the needed shearing force, which induces the transversal vibration, larger. These are of great significance for understanding of fasteners’ self-loosening and designing of bolted joints’ anti-loosening.
Dynamic Interaction Between Rotor and Axially-Magnetized Passive Magnetic Bearing Considering Magnetic Eccentricity
Authors: Enemark Søren , Santos Ilmar F. 
Published: March 2015

Passive magnetic bearings are known due to the excellent characteristics in terms of friction and no requirement of additional energy sources to work. However, passive magnetic bearings do not provide damping, are not stable and, depending on their design, may also introduce magnetic eccentricity. Such magnetic eccentricities are generated by discrepancies in magnet fabrication. In this framework the main focus of the work is the theoretical as well as experimental investigation of the non-linear dynamics of a rotor-bearing system with strong emphasis on the magnetic eccentricities and non-linear stiffness.
In this investigation passive magnetic bearings using axially-aligned neodymium cylinder magnets are investigated. The cylinder magnets are axially magnetised for rotor as well as bearings. Compared to bearings with radial magnetisation, the magnetic stiffness of axially-aligned bearings is considerably lower, nevertheless they allow for asymmetric stiffness mounting, and it could be beneficial for rotor stabilization.
A theoretical model is proposed to describe the non-linear rotor-bearing dynamics. It takes into account non-linear behaviour of the magnetic forces and their interaction with a multi-body system composed of rigid rotor and flexible foundation. The magnetic eccentricities of the shaft magnets are modelled using the distances (amplitudes) and directions (phase angles) between the shaft axis and the centre of the magnetic fields generated. A perturbation method, i.e. harmonic balancing, is used in order to evaluate the frequency response of the non-linear system.
The experimental validation of the model is carried out using a dedicated rotor-bearing system set-up. The test set-up consists of a vertical rigid shaft and disc supported by two passive magnetic bearings using axially-aligned neodymium cylinder magnets. The magnetic bearing housings are flexibly supported, allowing horizontal motions. The housings are connected to each other by means of elastic beams. The shaft is free in one end and coupled to a DC motor on the other by means of a flexible coupling. On the free end a disc is attached where imbalances and gyroscopic effect can be generated.
Comparison between theory and experiment shows high level of resemblance, which validates the theoretical model and the explanations for the quasi-static and dynamic responses. The magnetic eccentricities and mass imbalance effects are clearly detected and distinguished.
Experimental Assessment of Emitted Dose From Valved Holding Chamber Devices
Authors: Oliveira Ricardo F. , Silva Manuel V. , Machado Ana V. , Oliveira Manuel , Cabral-Marques Helena Maria , Teixeira Senhorinha F. , Teixeira José Carlos 
Published: March 2015

Due to the increasing worldwide incidence of asthma, a growing usage of inhalation devices has been observed. Some of the pressurized Metered Dose Inhalers (pMDI) limitations have been overcome by the introduction of newly and improved Valved Holding Chambers (VHC), resulting in good patient acceptance.
The efficiency is assessed by the VHC Emitted Dose (ED), i.e. the amount of drug available to the patient.
Using the pMDI salbutamol sulfate formulation (Ventolin® HFA-134a) as the test drug, several VHC devices were assessed. These latest were grouped by material characteristics: dissipative (OptiChamber Diamond®, AeroChamber Plus®, Vortex®, A2A Spacer®), non-dissipative (SpaceChamber Plus®, Compact SpaceChamber Plus®, Volumatic®) and stainless steel (Nebuchamber®).
The pMDI + VHC were assembled to a filter housing, which comprises an induction port with similar USP Throat dimensions, and connected to a vacuum pump (calibrated at 15, 26 and 40 L/min). Using UV-Vis Spectrophotometry equipment at 244 nm, it was possible to determine its concentration for later mass calculation. For all the VHC devices tested, the total mass recovery percentage was between 85% and 120%.
At 26 L/min, the Vortex® VHC has shown the highest ED (47.3 ± 1.8 %).
The ED may not be dependent on the volume of the VHC. Although, further analysis of the results suggests the existence of a linear correlation between the ED and the VHC body length.
SpaceChamber Plus® results show an increase of the ED and, subsequently, a decrease in VHC deposition fraction, with the increase of airflow.
Anterior Spinal Cord Contusion on Porcine Model
Authors: Cliche Francis , Mac-Thiong Jean-Marc , Petit Yvan 
Published: March 2015

Animal models are commonly used to study spinal cord injuries (SCI). These models aim to better understand the traumatic behaviour of the spinal cord in vivo. However, experimental SCI models usually simulate a posterior contusion of the spinal cord on small animals, which do not reproduce completely the SCI mechanisms in humans.
The objectives of the study are: 1) to develop an experimental anterior contusion of the spinal cord on porcine models, and 2) to compare biomechanical differences between ventral and dorsal approaches.
A total of 6 specimens were tested in vivo with a drop weight bench test. Impacts were produced at T10 with 5mm diameter impactor of 50g and dropped from a height of 100mm. Compression time was set to 5min for 4 specimens (2 ventral, 2 dorsal) and 60min for 1 ventral and 1 dorsal. The outcome measures were the compression displacement, blood pressure, heart rate and macroscopic inspection of the spinal cord.
This is the first study proposing an animal model of anterior SCI. Preliminary results suggest that there is a biomechanical difference between ventral and dorsal contusion approaches. A new bench test especially designed for ventral contusion will allow additional tests analyzing more variables, such as the motor evoked potentials and arterial blood flow.
Nonlinear Normal Modes and the LuGre Friction Model Parameter Identification
Authors: Hadji Abdallah , Mureithi Njuki 
Published: March 2015

A Hybrid friction model has recently been developed by Azizian and Mureithi [1] to simulate the general friction behavior between surfaces in contact. However, identification of the model parameters remains an unresolved problem.
To identify the parameters of the friction model, the following quantities are required: contact forces (friction and impact forces), the slip velocity and displacement in the contact region. Direct measurement of these quantities is difficult. In the present work, a beam clamped at one end and simply supported with the consideration of friction effect at the other is used as a mechanical amplifier of the friction effects at the microscopic level. Using this simplified approach, the contact forces, the sliding velocity and the displacement can be indirectly obtained by measuring the beam vibration response. A new method based on nonlinear modal analysis to calculate the contact forces is developed in the present work. The method is based on the modal superposition principle and Fourier series expansion.
For the harmonic balance method, two approaches were tested. The approach based on sub-harmonic forms gave the best results.
Signal reconstruction made it possible to accurately identify the parameters of the hybrid friction model with a multiple step approach.