Uncertainty of the Diffusion Measurements on Scaffolds for Cell Growth

2011 ◽  
Vol 312-315 ◽  
pp. 770-775 ◽  
Author(s):  
Guido Sassi ◽  
Marco Bernocco ◽  
Mariapaola Sassi
Keyword(s):  
Dynamic Properties ◽  
Fluid Dynamic ◽  
Solid Particles ◽  
Liquid Volume ◽  
Model Parameters ◽  
Diffusivity Measurement ◽  
Fitting Procedures ◽  
Definition Of

The regenerative medicine uses gel and porous solid matrices as scaffolds for the growth of the stem cells in 3D structures. The structural and fluid dynamic properties of the matrices have been recognized to highly affect the behaviour and functions of the cells. The procedures of production and the clinical use of the matrices need a reliable and reproducible characterization of their properties, this means that the concepts of metrology must be applied to the measurement and definition of all the relevant properties. This paper deals with the calculation of uncertainty for diffusivity measurement in solids and the role of uncertainty in designing the measurement. Diffusion of a solute in spherical solid particles dispersed in a limited liquid volume where considered as measurement method for a Ca-alginate polymer. The model sensitivity to the concentration measurements, the model parameters and the fitting procedures have been discussed.

Paradigm Function Morphology: Assumptions and Innovations

2020 ◽  
Author(s):  
Gregory Stump
Keyword(s):  
Inflectional Morphology ◽  
Formal Representation ◽  
The Core ◽  
Recent Innovation ◽  
Morphological Theory ◽  
Per Se ◽  
Fundamental Insight ◽  
Definition Of

Paradigm Function Morphology (PFM) is an evolving approach to modeling morphological systems in a precise and enlightening way. The fundamental insight of PFM is that words have both content and form and that in the context of an appropriately organized lexicon, a language’s morphology deduces a complex word’s form from its content. PFM is therefore a realizational theory: a language’s grammar and lexicon are assumed to provide a precise characterization of a word’s content, from which the language’s morphology then projects the corresponding form. Morphemes per se have no role in this theory; by contrast, paradigms have the essential role of defining the content that is realized by a language’s morphology. At the core of PFM is the notion of a paradigm function, a formal representation of the relation between a word’s content and its form; the definition of a language’s paradigm function is therefore the definition of its inflectional morphology. Recent elaborations of this idea assume a distinction between content paradigms and form paradigms, which makes it possible to account for a fact that is otherwise irreconcilable with current morphological theory—the fact that the set of morphosyntactic properties that determines a word’s syntax and semantics often differs from the set of properties (some of them morphomic) that determines a word’s inflectional form. Another recent innovation is the assumption that affixes and rules of morphology may be complex in the sense that they may be factored into smaller affixes and rules; the evidence favoring this assumption is manifold.

scholarly journals Beyond the Binary: Rethinking Gender Neutrality in Indian Rape Law

2016 ◽  
Vol 11 (2) ◽  
pp. 367-397
Author(s):  
Harshad PATHAK
Keyword(s):  
Human Rights ◽  
Rape Law ◽  
The Common ◽  
Definition Of ◽  
Human Rights Based Approach ◽  
Gender Neutrality ◽  
Gender Specific ◽  
Indian Penal Code

AbstractDespite expanding the definition of rape under the Indian Penal Code to include non-penile-vaginal acts of penetration, the said definition continues to conform to a gender-specific notion of rape, based on a predetermined characterization of the victim-perpetrator framework on the basis of their genders. Herein, I will critique this idea of gender specificity in Indian rape law on the grounds that it reinforces a binary notion of gender, and results in gross underinclusion. Instead, it is more appropriate to adopt a human-rights-based approach in defining the offence of rape, and negate the role of gender in identifying the victims and perpetrators of an act of rape. The argument is pillared on a state’s obligation to not discriminate on the basis of sex, the recognition of transgender rights, and an assessment of the common grounds for opposing gender neutrality in Indian rape law.

scholarly journals VISCOUS FINGERING IN MISCIBLE, IMMISCIBLE AND REACTIVE FLUIDS

2003 ◽  
Vol 17 (01n02) ◽  
pp. 15-20 ◽  
Author(s):  
PATRICK GROSFILS ◽  
JEAN PIERRE BOON
Keyword(s):  
Dynamic Properties ◽  
Static Properties ◽  
Two Fluids ◽  
Experimental Systems ◽  
Reactive Fluids ◽  
Bgk Approximation ◽  
Boltzmann Method ◽  
Effect Of Surface

With the Lattice Boltzmann method (using the BGK approximation) we investigate the dynamics of Hele-Shaw flow under conditions corresponding to various experimental systems. We discuss the onset of the instability (dispersion relation), the static properties (characterization of the interface) and the dynamic properties (growth of the mixing zone) of simulated Hele-Shaw systems. We examine the role of reactive processes (between the two fluids) and we show that they have a sharpening effect on the interface similar to the effect of surface tension.

scholarly journals Role of metformin pregravid preparation patients with prediabetes impaired glucose toletance

2015 ◽  
Vol 64 (3) ◽  
pp. 18-25
Author(s):  
Evgeniy Konstantinovich Komarov ◽  
Tamara Aleksandrovna Pluzhnikova
Keyword(s):  
Low Frequency ◽  
Free Testosterone ◽  
Control Group ◽  
Perinatal Complications ◽  
Insulin Resistence ◽  
Group I ◽  
Definition Of ◽  
High Level

Tasks of investigation were concluded the characterization of insulin resistence (IR) and hormonal features in patients with prediabetes and influence of diet or metformin on the course of pregnancy and perinatal complications. There were examined 61 womans. The OGTT, definition of insulin levels in plasma and index IR were performed in all patiens. OGTT and index IR were normal in 14 womans (control group I). OGTT was normal but index IR was impared in 33 womans (group IR - II). From this group 22 womans were treated with diet (II A group) and 11 womans treated with metformin (IIB group). OGTT and index IR were abnormal in 14 womans (impared OGTT - III group), they were treated with metformin. Dose of metformin was 1500 mg/d, threatment was continueted for 3-4 manths. Conclusion: Used indexes IR basal and two hour after glucose load were significant in definition of normal and decreased insulin sensitivity (IR). Presence of IR is accompanied by high level of free testosterone in blood without impared secretion of ovarian and suprarenal androgens. There was impared sensitivity of endometrium of secretory stage. The frequency of obstetric and perinatal complications in patients receiving diet not differ from patients treated with metformin. There was only a tendercy to low frequency of threatening miscarriages befor 12 weeks of gestations in paitiens receiving metformin. Development of GDM was observed in 13,1 % of patiens only with presence of IR. The use of metformin in pregravidal stage preserved the development of macrosomia in offsprings of patients with prediabetes.

Settling behaviour of particles in Rayleigh-Benard convection

2020 ◽  
Author(s):  
Vojtech Patocka ◽  
Enrico Calzavarini ◽  
Nicola Tosi
Keyword(s):  
Theoretical Model ◽  
Response Time ◽  
Scaling Laws ◽  
Numerical Study ◽  
Fluid Dynamic ◽  
Solid Particles ◽  
Rigid Sphere ◽  
Model Parameters ◽  
Magma Ocean ◽  
Settling Behaviour

<p>Our numerical study evaluates the settling rate of solid particles, suspended in a highly <br>vigorous, finite Prandtl number convection of a bottom heated fluid. We explore a broad <br>range of model parameters, covering particle types appearing in various natural systems, <br>and focus in particular on crystals nucleating during the cooling of a magma ocean. The <br>motion of inertial particles within thermal convection is non-trivial, and under idealized <br>conditions of spherical shaped particles with small Reynolds number it follows the <br>Maxey-Riley equation (Maxey and Riley, 1983). Two scaling laws exist for the settling <br>velocities in such system: for particles with small but finite response time, the Stokes' <br>law is typically applied. For particles with a vanishing response time, a theoretical model <br>was developed by Martin and Nokes (1989), who also validated their prediction with analogue <br>experiments. </p><p>We develop a new theoretical model for the settling velocities. Our approach describes <br>sedimentation of particles as a random process with two key constituents: i) transport <br>from convection cells into slow regions of the flow, and ii) the probability of escaping <br>slow regions if a particle enters them. By quantifying the rates of these two processes, <br>we derive a new equation that bridges the gap between the above mentioned scaling laws. <br>Moreover, we identify four distinct regimes of settling behaviour and analyze the lateral <br>distribution of positions where particles reach the bottom boundary. Finally, we apply our <br>results to the freezing of a magma ocean, making inferences about its equilibrium vs <br>fractional crystallization. The numerical experiments are performed in 2D cartesian geometry <br>using the freely available code CH4 (Calzavarini, 2019).</p><p>References:<br>Maxey, M. R. and Riley, J. J.(1983): Equation of motion for a small rigid sphere in a nonuniform flow. <br>Physics of Fluids, 26(4), 883-889.</p><p>Martin, D and Nokes, R (1989): A fluid-dynamic study of crystal settling in convecting magmas. <br>Journal of Petrology, 30(6), 1471-1500.</p><p>Calzavarini, E (2019): Eulerian–Lagrangian fluid dynamics platform: The ch4-project. Software Impacts, 1, 100002.</p>

scholarly journals PROPERDIN FACTOR D: CHARACTERIZATION OF ITS ACTIVE SITE AND ISOLATION OF THE PRECURSOR FORM

1974 ◽  
Vol 139 (2) ◽  
pp. 355-366 ◽  
Author(s):  
Douglas T. Fearon ◽  
K. Frank Austen ◽  
Shaun Ruddy
Keyword(s):  
Active Site ◽  
Gel Filtration ◽  
Serine Esterase ◽  
Factor B ◽  
Alternate Pathway ◽  
Serine Esterases ◽  
Definition Of ◽  
Chromatographic Isolation

The activity of properdin factor D was measured by the generation of the hemolytically active cellular intermediate, EAC43B(D), bearing the C3b-dependent alternate pathway C3 convertase. Treatment of factor D with DFP prevented formation of EAC43B(D); thus, a serine esterase is essential for the generation of the alternate pathway C3 convertase, a situation analogous to the role of C1 in the formation of the classical C3 convertase, C42. The definition of factor D as a serine esterase prompted a search for its proenzyme form, and resulted in the chromatographic isolation from plasma of a single peak of trypsin-inducible factor D activity, distinct from activated factor D. Analytical gel filtration indicated an apparent mol wt of 25,000. This protein from which trypsin elaborated factor D activity, as assessed by the formation of EAC43B(D), the generation of the CoVF-dependent C3 convertase, and the cleavage of factor B in the presence of C3b, was designated "precursor factor D." The DFP resistance of precursor factor D, and the susceptibility of its trypsin-activated form to inactivation by DFP is analogous to the behavior of other plasma serine esterases, including C1.

Translational science in chronic kidney disease

2017 ◽  
Vol 131 (14) ◽  
pp. 1617-1629 ◽  
Author(s):  
Maria Dolores Sanchez-Niño ◽  
Ana B. Sanz ◽  
Adrian M. Ramos ◽  
Marta Ruiz-Ortega ◽  
Alberto Ortiz
Keyword(s):  
Chronic Kidney Disease ◽  
Kidney Disease ◽  
Translational Research ◽  
Basic Research ◽  
Clinical Development ◽  
Hypertensive Nephropathy ◽  
Recent Advances ◽  
Definition Of

The KDIGO definition of chronic kidney disease (CKD) allowed a more detailed characterization of CKD causes, epidemiology and consequences. The picture that has emerged is worrisome from the point of view of translation. CKD was among the fastest growing causes of death in the past 20 years in age-adjusted terms. The gap between recent advances and the growing worldwide mortality appears to result from sequential roadblocks that limit the flow from basic research to clinical development (translational research type 1, T1), from clinical development to clinical practice (translational research T2) and result in deficient widespread worldwide implementation of already available medical advances (translational research T3). We now review recent advances and novel concepts that have the potential to change the practice of nephrology in order to improve the outcomes of the maximal number of individuals in the shortest possible interval. These include: (i) updating the CKD concept, shifting the emphasis to the identification, risk stratification and care of early CKD and redefining the concept of aging-associated ‘physiological’ decline of renal function; (ii) advances in the characterization of aetiological factors, including challenging the concept of hypertensive nephropathy, the better definition of the genetic contribution to CKD progression, assessing the role of the liquid biopsy in aetiological diagnosis and characterizing the role of drugs that may be applied to the earliest stages of injury, such as SGLT2 inhibitors in diabetic kidney disease (DKD); (iii) embracing the complexity of CKD as a network disease and (iv) exploring ways to optimize implementation of existing knowledge.

Characterization of Thermoplastic Elastomers for Design Efforts

2014 ◽  
Vol 905 ◽  
pp. 161-166
Author(s):  
Zoltan Major ◽  
Matei C. Miron ◽  
Umut D. Cakmak
Keyword(s):  
Experimental Data ◽  
Thermoplastic Elastomer ◽  
Material Model ◽  
Thermoplastic Elastomers ◽  
Failure Behavior ◽  
Model Parameters ◽  
Material Models ◽  
Fitting Procedures ◽  
Relevant Material

Different grades of several thermoplastic elastomer types were selected and are investigated over a wide frequency/time, temperature and loading range in a research project of the authors. Relevant material models are selected for different loading situations and based on these experimental data the material model parameters were determined either directly or by applying fitting procedures. These models along with the proper data were used for modeling the deformation and the failure behavior of typical engineering thermoplastic elastomer components. Furthermore, based on the modeling of various elastomers under different service relevant loading situation several design proposals were formulated.

Second Order Polynomial Model for Fluid Dynamics in High Pressure

2009 ◽  
Author(s):  
Juho-Pekka Karjalainen ◽  
Reijo Karjalainen ◽  
Kalevi Huhtala ◽  
Matti Vilenius
Keyword(s):  
Dynamic Properties ◽  
Fluid Model ◽  
Fluid Dynamic ◽  
Measuring Method ◽  
Second Order ◽  
Model Parameters ◽  
Hydraulic Fluid ◽  
Measurement Results ◽  
Order Polynomial ◽  
Fluid Characteristics

This paper suggests second order polynomials for modeling hydraulic fluid dynamic properties — tangent bulk modulus, density and speed of sound in fluid. Model parameters can be calculated from ISO fluid characteristics data available for every commercial hydraulic fluid. The accuracy of the models is verified with measurements at pressures up to 1500 bar. The measurement results as well as the measuring method are also introduced. Although the models are quite simple, correlation with the measurement results is excellent.

scholarly journals Methodologies for geological-geotechnical characterization of rock masses: role of geomechanical classifications and indexes

2021 ◽  
Vol 942 (1) ◽  
pp. 012025
Author(s):  
C Santa ◽  
I Fernandes ◽  
HI Chaminé
Keyword(s):  
Rock Mass ◽  
Site Investigation ◽  
Classification Systems ◽  
Rock Masses ◽  
Rock Types ◽  
Work Cycle ◽  
Definition Of ◽  
Engineering Projects

Abstract The geological and geotechnical description and evaluation are fundamental in engineering projects and the extractive industry, emphasizing underground environments where the rock mass is subjected to high stresses. In excavating rock masses, the classification systems contribute to parameterizing the rock material and rock mass characteristics. In addition, it is essential to the definition of the support to be applied, which limits are often based on the value of the geomechanical classifications. Therefore, determining the characteristics demands structured techniques to reconcile rigour, accuracy, and efficiency in the execution of the site investigation to obtain reliable data in an integrated action of the work cycle. This study analyses the applicability and feasibility of the Geological Strenght Index (GSI), based on field data collected in different underground projects. Various geological environments and distinct excavation purposes were selected to evaluate the possibility of expanding this version of the GSI to other rock types with the inclusion of the influence of groundwater on this classification.

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