Studies on a Levonorgestrel-Releasing Trade Plastic Device and on a Similar Polyurethane Foam Used as a Levonorgestrel Carrier

2019 ◽  
Vol 56 (3) ◽  
pp. 543-547
Author(s):  
Flavius Olaru ◽  
Dana Stoian ◽  
Delia Berceanu Vaduva ◽  
Alina Corpade ◽  
Florin Birsasteanu ◽  
...  
Keyword(s):  
Skin Irritation ◽  
Oral Route ◽  
Point Of View ◽  
Intrauterine Devices ◽  
Daily Amount ◽  
Pu Foam ◽  
The One ◽  
Structural Point ◽  
Copper Iud

Hormonal Intrauterine Devices (IUD) were developed based on copper IUD with the role to release a daily amount of hormones. From a structural point of view Levonorgestrel-IUD (L-IUD) is a small T-shaped piece of plastic, which contains levonorgestrel. When compared with the oral route of L-IUD administration, it provides some advantages because it releases levonorgestrel directly into the uterus. Our aims were: (1) to compare the thickness of uterine jonctional zone (UJZ) in two groups of patients with and without inserted L-IUD, (2) to evaluate the changes in thickness of UJZ after the insertion of L-IUD in two patients with adenomyosis, and (3) to obtain and to characterize a similar T-shaped polyurethane (PU) foam used as a levonorgestrel delivery system. On the one hand, the results confirm that L-IUD is effective in thinning the UJZ and in the treatment of adenomyosis, while on the other hand, the characterization of the PU materials (Zetasizer measurements, their thermal degradation, UV-Vis spectra and skin irritation tests) revealed that this polymer can be used as a safety and prolonged levonorgestrel carrier.

scholarly journals Crystallographic and structural characterization of heterometallic platinum compounds Part VII. Heterohepta- and heterooctanuclear clusters

2014 ◽  
Vol 13 (1) ◽  
Author(s):  
Milan Melnik ◽  
Peter Mikuš ◽  
Clive E. Holloway
Keyword(s):  
Structural Characterization ◽  
Structural Parameters ◽  
Bond Distance ◽  
Point Of View ◽  
Platinum Compounds ◽  
Metal Atoms ◽  
Platinum Clusters ◽  
Structural Point

AbstractThis review classifies and analyzes over fifty heterohepta- and heterooctanuclear platinum clusters. There are eight types of metal combinations in heteroheptanuclear: Pt6M, Pt5M2, Pt4M3, Pt3M4, Pt2M5, PtM6, Pt3Hg2Ru2 and Pt2Os3Fe2. The seven metal atoms are in a wide variety of arrangements, with the most common being one in which the central M atom (mostly M(I)) is sandwiched by two M3 triangles. Another arrangement often found is an octahedron of M6 atoms asymmetrically capped by an M atom. The shortest Pt-M bond distances (non-transition and transition) are 2.326(1) Å (M = Ga) and 2.537(6) Å (M = Fe). The shortest Pt-Pt bond distance is 2.576(2) Å.In heterooctanuclear platinum clusters there are eight types of metal combinations: Pt6M2, Pt4M4, Pt3Ru5, Pt2M6, PtM7, Pt2W4Ni2, PtAu6Hg and PtAu5Hg2. From a structural point of view, the clusters are complex with bicapped octahedrons of eight metal atoms prevailing. The shortest Pt-M bond distances (non-transition and transition) are 2.651(3) Å (M = Hg) and 2.624(1) Å (M = Os). The shortest Pt-Pt bond distance is 2.622(1) Å. These values are somewhat longer than those in the heteroheptanuclear clusters. Several relationships between the structural parameters were found, and are discussed and compared with the smaller heterometallic platinum clusters

scholarly journals Detection Limits of DLS and UV-Vis Spectroscopy in Characterization of Polydisperse Nanoparticles Colloids

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Emilia Tomaszewska ◽  
Katarzyna Soliwoda ◽  
Kinga Kadziola ◽  
Beata Tkacz-Szczesna ◽  
Grzegorz Celichowski ◽  
...  
Keyword(s):  
Light Scattering ◽  
Dynamic Light Scattering ◽  
Point Of View ◽  
Spectroscopy Analysis ◽  
Force Microscopy ◽  
Atomic Force ◽  
Transmission Electron ◽  
Vis Spectroscopy ◽  
The One

Dynamic light scattering is a method that depends on the interaction of light with particles. This method can be used for measurements of narrow particle size distributions especially in the range of 2–500 nm. Sample polydispersity can distort the results, and we could not see the real populations of particles because big particles presented in the sample can screen smaller ones. Although the theory and mathematical basics of DLS technique are already well known, little has been done to determine its limits experimentally. The size and size distribution of artificially prepared polydisperse silver nanoparticles (NPs) colloids were studied using dynamic light scattering (DLS) and ultraviolet-visible (UV-Vis) spectroscopy. Polydisperse colloids were prepared based on the mixture of chemically synthesized monodisperse colloids well characterized by atomic force microscopy (AFM), transmission electron microscopy (TEM), DLS, and UV-Vis spectroscopy. Analysis of the DLS results obtained for polydisperse colloids reveals that several percent of the volume content of bigger NPs could screen completely the presence of smaller ones. The presented results could be extremely important from nanoparticles metrology point of view and should help to understand experimental data especially for the one who works with DLS and/or UV-Vis only.

scholarly journals Synthesis and Characterization of Some Ester-type Biolubricants of Soiabean Fatty Acids

2017 ◽  
Vol 54 (2) ◽  
pp. 386-389 ◽  
Author(s):  
Sorina Boran ◽  
Sabina Nitu
Keyword(s):  
Fatty Acids ◽  
Point Of View ◽  
Synthesis And Characterization ◽  
Synthetic Ester ◽  
Microwave Reactor ◽  
Tribotechnical Properties ◽  
Physico Chemical ◽  
Hydroxyl Compounds ◽  
Structural Point

Growing demands from industry for the use of eco-friendly lubricants led research towards finding environmentally friendly products with superior lubricating characteristics. Vegetable oils and synthetic ester oils are competitive base oils used to obtain lubricants with good physico-chemical, rheological and tribotechnical properties, biodegradable lubricants without negative environmental impacts. In this study we aimed the synthesis and characterization of bioesters with lubricant properties, using as acid component the soybean oil fatty acids in conjunction with the following hydroxyl compounds n-buthanol (P1) and 1,2-propilenglycole (P2), respectively. These complex esters were synthesized in a microwave reactor in a single stage in the presence of the catalyst at the reflux temperature. Characterization was carried out in the respective of structural point of view and as a lubricant.

Structure et Signification : problème de méthode en sociologie des organisations claustrales

1971 ◽  
Vol 18 (1) ◽  
pp. 27-44 ◽  
Author(s):  
Emile Servais ◽  
Francis Hambye
Keyword(s):  
Cultural Models ◽  
Religious Life ◽  
Point Of View ◽  
Dominant Culture ◽  
Positive Meaning ◽  
Internal Forces ◽  
The Moment ◽  
The One ◽  
High Credibility ◽  
Structural Point

In adopting a structural point of view in order to analyse institutionalized forms of religious life, we were led not only to show the totality or the system from which the different elements take their meaning, but also we had the possibility of comparing organized religious life with other forms of social organizations. Using this method, it becomes possible, on the one hand, to bring to light the latent functions of certain elements of the system ; and on the other hand, to question the credibility of the meanings which are officially attributed to organized religious life. Among the elements which go to make up the meaning of religious life, this study is concerned with the model of authority. In order to describe the tensions which organized religious life is undergoing at the moment, one can separate the various institutions by treating them as systems which are evolving under the single pressure of internal forces. However, if we wish to explain such phenomena, it is indispensable to reinsert the structure which is being studied into a larger cultural setting, the dominant culture of the period. In fact, organized religious life confers a positive meaning on its institutions in taking up again in an unconscious way the cultural models which have been interiorized by the whole of society in a diffused manner, which because of this possess es a high credibility.

Trends in the Analysis of Biopharmaceuticals by HPLC

2020 ◽  
Vol 16 (1) ◽  
pp. 52-58
Author(s):  
Angela Tartaglia ◽  
Marcello Locatelli ◽  
Victoria Samanidou
Keyword(s):  
Living Organism ◽  
Point Of View ◽  
European Medicines Agency ◽  
Low Molecular Weight ◽  
Immune Disorders ◽  
Biological Drugs ◽  
Post Translational Modifications ◽  
Regulatory Guidelines ◽  
Structural Point

Background: Biopharmaceuticals are biological drugs consisting of a complex compound that can be produced by a living organism or derive from it. Biopharmaceuticals are very complicated compounds from structural point of view and for this reason, they cannot be fully characterized in terms of their structure with current analytical methods as it happens instead of low molecular weight chemicals drugs. Introduction: The regulatory guidelines require the characterization of the primary or higher sequence of these molecules and the characterization of any post-translational modifications. The use of biopharmaceuticals has really grown in the last few years: in 2016, the number of biopharmaceuticals approved by the Food and Drug Administration (FDA) and European Medicines Agency (EMA) for use in humans’ diseases was 1357. From 2013 to 2016, 73 of these compounds were approved for the treatment of cancer, inflammation, immune disorders, infections, anemia and cardiovascular diseases. Aim/Conclusion: The aim of the present review is to provide an overview of recent approaches for the characterization of biopharmaceutical products in HPLC that have been presented in the literature in the last years.

scholarly journals Yablo’s Paradox, the Liar, and Referential Contradictions from a Graph Theory Point of View

2021 ◽  
pp. 101-104
Author(s):  
Gustavo Bodanza
Keyword(s):  
Fixed Point ◽  
Graph Theory ◽  
Point Of View ◽  
Graph Theoretic ◽  
Admissible Sets ◽  
Special Cases ◽  
Theory Point ◽  
The One ◽  
The Liar

F -systems are useful digraphs to model sentences that predicate the falsity of other sentences. Paradoxes like the Liar and the one of Yablo can be analyzed with that tool to find graph-theoretic patterns. In this paper we studied this general model consisting of a set of sentences and the binary relation ‘... affirms the falsity of...’ among them. The possible existence of non-referential sentences was also considered. To model the sets of all the sentences that can jointly be valued as true we introduced the notion of conglomerate, the existence of which guarantees the absence of paradox. Conglomerates also enabled us to characterize referential contradictions, i.e., sentences that can only be false under a classical valuation due to the interactions with other sentences in the model. A Kripke-style fixed-point characterization of groundedness was offered, and complete (meaning that every sentence is deemed either true or false) and consistent (meaning that no sentence is deemed true and false) fixed points were put in correspondence with conglomerates. Furthermore, argumentation frameworks are special cases of F -systems. We showed the relation between local conglomerates and admissible sets of arguments and argued about the usefulness of the concept for the argumentation theory.

scholarly journals An Extension of the Concept of Derivative: Its Application to Intertemporal Choice

Mathematics ◽  
2020 ◽  
Vol 8 (5) ◽  
pp. 696
Author(s):  
Salvador Cruz Rambaud ◽  
Blas Torrecillas Jover
Keyword(s):  
Behavioral Finance ◽  
Intertemporal Choice ◽  
Point Of View ◽  
Financial Mathematics ◽  
Economic Problems ◽  
Scientific Disciplines ◽  
The One ◽  
Novel Concept ◽  
Decreasing Impatience

The framework of this paper is the concept of derivative from the point of view of abstract algebra and differential calculus. The objective of this paper is to introduce a novel concept of derivative which arises in certain economic problems, specifically in intertemporal choice when trying to characterize moderately and strongly decreasing impatience. To do this, we have employed the usual tools and magnitudes of financial mathematics with an algebraic nomenclature. The main contribution of this paper is twofold. On the one hand, we have proposed a novel framework and a different approach to the concept of relative derivation which satisfies the so-called generalized Leibniz’s rule. On the other hand, in spite of the fact that this peculiar approach can be applied to other disciplines, we have presented the mathematical characterization of the two main types of decreasing impatience in the ambit of behavioral finance, based on a previous characterization involving the proportional increasing of the variable “time”. Finally, this paper points out other patterns of variation which could be applied in economics and other scientific disciplines.

scholarly journals Development and application of methods to characterize micro semi-finished products and micro components

2018 ◽  
Vol 190 ◽  
pp. 15012
Author(s):  
Bernd Köhler ◽  
Brigitte Clausen ◽  
Hans-Werner Zoch
Keyword(s):  
Mechanical Testing ◽  
Electron Backscatter Diffraction ◽  
Decisive Role ◽  
Point Of View ◽  
X Ray ◽  
Analysis Techniques ◽  
Microhardness Testing ◽  
The One ◽  
Backscatter Diffraction

In the production of semi-finished products for the production of microcomponents and the components themselves, the characterization of their physical properties is of particular importance. Due to the often oligocrystalline character of these semi-finished products and components, it is necessary to use a suitable testing technique for static and dynamic investigations, as the mechanical properties are not transferable from the macroscopic point of view. In addition, the micro semi-finished products and components often show inhomogeneities induced by the manufacturing process. On the one hand, these are directly reflected in the microstructure and on the other hand they have an effect on quantities such as hardness or residual stresses, which play a decisive role in the application. Mechanical testing, conventional metallography, scanning electron microscopy (SEM), electron backscatter diffraction (EBSD), ultra-microhardness testing and X-ray residual stress analysis were used as measuring and analysis techniques suitable for the sub-millimeter range. In the following, the possibilities and limitations of two these methods are illustrated using the example of mechanical testing and EBSD. In this paper several examples for possible characterization techniques are given.

Long-run Tendencies in Foreign Trade: With a Statistical Study of French Trade Structure 1871–1939

1971 ◽  
Vol 31 (4) ◽  
pp. 804-821 ◽  
Author(s):  
Jean Sylvain Weiller
Keyword(s):  
International Trade ◽  
Foreign Trade ◽  
Statistical Study ◽  
Trade Flows ◽  
Point Of View ◽  
The United Kingdom ◽  
Long Run ◽  
Complete Disruption ◽  
The One ◽  
Structural Point

Economists who have studied the evolution of trade transactions between the two world wars have often stressed the existence of an obvious paradox: despite the disturbances brought about by the war period, the territorial changes, the monetary difficulties and the crises, international trade as a whole and particularly from a structural point of view, had a tendency, after a few years of complete disruption, to return to a pre-war pattern of evolution. Trade flows were returning to a distribution very similar to the one prevailing in 1913, and changes were occurring in the same direction as those of the 1896–1913 period. Certain countries endured great difficulties in the readaptation process, especially the United Kingdom, whose “structural crises” have often been cited. But the very changes that were sources of anxiety for English rulers were less a result of the transformation or the acceleration of pre-war tendencies than of their continuity.

Understanding functional illiteracy from a policy, adult education, and cognition point of view: Towards a joint referent framework

2019 ◽  
Vol 30 (2) ◽  
pp. 109-122
Author(s):  
Aleksandar Bulajić ◽  
Miomir Despotović ◽  
Thomas Lachmann
Keyword(s):  
Adult Education ◽  
Operational Definition ◽  
Literacy Skills ◽  
Point Of View ◽  
Industrialized Countries ◽  
Functional Illiteracy ◽  
Scale Levels ◽  
Components Of Reading ◽  
The One ◽  
Definition Of

Abstract. The article discusses the emergence of a functional literacy construct and the rediscovery of illiteracy in industrialized countries during the second half of the 20th century. It offers a short explanation of how the construct evolved over time. In addition, it explores how functional (il)literacy is conceived differently by research discourses of cognitive and neural studies, on the one hand, and by prescriptive and normative international policy documents and adult education, on the other hand. Furthermore, it analyses how literacy skills surveys such as the Level One Study (leo.) or the PIAAC may help to bridge the gap between cognitive and more practical and educational approaches to literacy, the goal being to place the functional illiteracy (FI) construct within its existing scale levels. It also sheds more light on the way in which FI can be perceived in terms of different cognitive processes and underlying components of reading. By building on the previous work of other authors and previous definitions, the article brings together different views of FI and offers a perspective for a needed operational definition of the concept, which would be an appropriate reference point for future educational, political, and scientific utilization.

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