MEASUREMENTS AND CHARACTERIZATIONS OF MECHANICAL PROPERTIES OF HUMAN SKINS

2013 ◽  
Vol 24 ◽  
pp. 1360029
Author(s):  
HAN WOOK SONG ◽  
YON KYU PARK

A skin is an indispensible organ for humans because it contributes to metabolism using its own biochemical functions and protects the human body from external stimuli. Recently, mechanical properties such as a thickness, a friction and an elastic coefficient have been used as a decision index in the skin physiology and in the skin care market due to the increased awareness of wellbeing issues. In addition, the use of mechanical properties is known to have good discrimination ability in the classification of human constitutions, which are used in the field of an alternative medicine. In this study, a system that measures mechanical properties such as a friction and an elastic coefficient is designed. The equipment consists of a load cell type (manufactured by the authors) for the measurements of a friction coefficient, a decompression tube for the measurement of an elastic coefficient. Using the proposed system, the mechanical properties of human skins from different constitutions were compared, and the relative repeatability error for measurements of mechanical properties was determined to be less than 2%. Combining the inspection results of medical doctors in the field of an alternative medicine, we could conclude that the proposed system might be applicable to a quantitative constitutional diagnosis between human constitutions within an acceptable level of uncertainty.

Holzforschung ◽  
2017 ◽  
Vol 71 (12) ◽  
pp. 939-949 ◽  
Author(s):  
Qiwei Li ◽  
Jihong Wu ◽  
Yesheng Wang ◽  
Xiaoming Lian ◽  
Feilong Wu ◽  
...  

AbstractThe genusDalbergiacontains approximately 250 species with many valuable trees being destroyed by targeted and illegal logging. DNA barcoding is a reliable method for the molecular identification of different species and resources conservation. In the present study, the specimen discrimination ability of internal transcribed spacer (ITS),matK,rbcL andpsbA-trnH barcoding were tested onDalbergiasequences, downloaded from the National Center for Biotechnology Information (NCBI), and the combined barcoding ITS+matK+rbcL was used to identify unknown specimens. It was found that ITS+matK+rbcL have good discrimination rates based on the analysis methods best match (BM) and best close match (BCM). These barcodes also have the best performance concerning barcode gap distribution, and are able to discriminate unknown specimens from South-China. Furthermore, it was demonstrated thatD. tamarindifoliaandD. rubiginosaare also relatively close to sister-speciesD. pinnataandD. candenatensiswithin the phylogeneticDalbergiatree. Considering the overall performance of these barcodes, we suggest that the ITS+matK+rbcL region is a suitable barcode for identifyingDalbergiaspecies.


Author(s):  
S Giljean ◽  
M Bigerelle ◽  
K Anselme

This study aims to perform a multiscale analysis of abraded surfaces of 316L austenitic stainless steel and titanium alloys (TiAl6V4) grinded at different paper grades. The authors propose to answer the following question: For a given distribution of silicon carbide grains of the paper, what is the best roughness parameter and at which scale must it be evaluated better to discriminate the effect of the mechanical properties of the materials? Paper grades from 80 to 4000 were used under identical pressure and erosion time. It can be concluded that the values of the amplitude roughness parameters depend on the observation scale. It is outlined that the abrasion process is very reproducible. A statistical analysis is then proposed, first, to define a classification of the relevance of the roughness parameters for each grain size distribution, and second, to determine at which scale the mechanical properties of the bulk are more influenced for all paper grades. Finally, at relevant scales, the Abbott amplitude parameters roughness kernel (RK) is the best parameter to discriminate the paper grade effect. The mean distance between asperities (SM) is the preferred method for determining the wear effect on materials and the linear mean normalizing autocorrelation (AMNLN) is the preferred method for determining the interaction between paper grade and materials.


Filomat ◽  
2020 ◽  
Vol 34 (2) ◽  
pp. 609-614
Author(s):  
Burcu Aydin ◽  
Fusun Yalcin ◽  
Ozge Ozer ◽  
Gurhan Yalcin

Marbles are secondary decomposition products formed by metamorphism of limestone. Effective classification of marble quarries in terms of quality enables the selection of a sustainable production method and safety application. This evaluation is based on physico-mechanical properties of the samples. Obtained results of physico-mechanical properties of the marbles were statistically analyzed using Stata 14 and SPSS 21 software. The marbles indicated mostly normal physical and mechanical properties. A strong inverse relationship exists between Abrasion Value and Knoop Hardness Determination that indicates a significant nonlinear relationship. Samples were distinguished into 3 groups of close similarity and related properties. The estimated value of the parameters is in the 95 % confidence interval. The equation obtained by regression analysis was used for the determination of resistance to abrasion.


2020 ◽  
Author(s):  
Mingjian Bai ◽  
Shilong Wang ◽  
Ruiqing Ma ◽  
Ying Cai ◽  
Yiyan Lu ◽  
...  

Abstract Background Pseudomyxoma peritonei (PMP) is a rare disease, the prognosis of overall survival (OS) is affected by many factors, present study aim to define independent prediction indicators and establish a nomogram for PMP patients.Methods 119 PMP patients received cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) in our center for the first time were included between 01/06/2013 and 22/11/2019 . The log-rank test was used to compare the OS rate among groups, subsequently, variables with P<0.10 were subjected to multivariate Cox model for defining independent prediction indicators. Finally, the nomogram prediction models will be established and for internal validation.Results Multivariate analysis showed Sex, D-Dimer, CA125, CA19-9, PCI, and degree of radical surgery were independently associated with OS in PMP patients. A nomogram was plotted based on the independent predictive factors and undergone internal validation, ROC analysis was performed to calculate discrimination ability of the nomogram, the C-index was 0.880 (95%CI: 0.806- 0.933) and calibration plots showed good performance. Conclusions Six independent prognostic factor for predicting survival in PMP patients were difined, the nomogram has a good discrimination ability for individual risk predition, more researches are needed to verify and improve the prediction model.


Author(s):  
Yoshihiko Hangai ◽  
Kenji Okada ◽  
Yuuki Tanaka ◽  
Tsutomu Matsuura ◽  
Kenji Amagai ◽  
...  

Holzforschung ◽  
2019 ◽  
Vol 73 (6) ◽  
pp. 517-523 ◽  
Author(s):  
Tingting Feng ◽  
Qiwei Li ◽  
Yesheng Wang ◽  
Simin Qiu ◽  
Mengling He ◽  
...  

AbstractAquilariaLam. is an important group of trees that produce agarwood, which is widely used for manufacturing medicine, perfumes and incense. The members of the genusAquilariaare close to being extinct due to illegal harvesting and are now protected in many countries. In this study, five DNA barcodes [internal transcribed spacer (ITS), maturase K (matK),psbA-trnH, ribulose bisphosphate carboxylase (rbcL) andtrnL-trnF] and their combinations were evaluated for the discrimination of the major (16 out of 21) species ofAquilariabased on three criteria: sequence variation, genetic distances and the discrimination ability. In addition, we attempted to determine the phylogenetic relationship betweenAquilariaandGyrinopsspecies using three phylogenetic analysis methods. We observed that the combination barcode ITS+trnL-trnF had a good discrimination ability based on the best match and best close match methods, provided more genetic information, and clearly indicated the comprehensive phylogenetic relationship between mostAquilariaandGyrinopsspecies. Considering the overall performance of these barcodes, the ITS+trnL-trnF is a suitable barcode for the identification ofAquilariaspecies.


2011 ◽  
Vol 462-463 ◽  
pp. 1176-1181
Author(s):  
Shahril Anuar Bahari ◽  
Mansur Ahmad

In this study, the classification of modes of failure, the observation of microscopic failures and the mechanical properties of Semantan bamboo strips were investigated. Specimens were loaded in bending and shear parallel to grain. Specimens were taken from internodes and node parts in bottom, middle and top portions of bamboo culms. From the classification, different modes of failure occurred in different parts of Semantan bamboo culms loaded in bending and shear. From the microscopic observation, the failures occurred in both parenchyma and vascular bundles regions for all classified failure modes from all tests, except for Even Splitting Mode from shear. This mode exhibited failure in parenchyma only, without any failure in vascular bundles regions. The Maximum Stress (σml) values between failure modes for both tests were significantly different. Generally, anatomical behaviour at different culm’s parts had influenced the different modes of failure and microscopic failures of Semantan bamboo strips loaded in bending and shear.


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