Basic Structural Differences Research Articles

Surface-Confined Metal–Organic Precursors Comprising Naphthalene-Like Derivatives with Differently Distributed Halogen Substituents: A Monte Carlo Model

The on-surface synthesis of organic polymers has been recently recognized as a useful method to create low-dimensional covalently bonded structures with tailorable topology and functions. In this work, the Monte Carlo simulation method was used to study the metal–organic precursors of covalent polymers formed in the Ullmann-type coupling reaction of halogenated naphthalene derivatives. To this purpose, a coarse-grained model was proposed in which the monomers, represented by a pair of interconnected segments, and two-coordinate metal atoms (one segment) were adsorbed on a triangular lattice-mimicking (111) catalytically active crystalline surface. Different distributions of halogen atoms in the naphthalene molecules were modeled using the directional interactions assigned to these units, sustaining the resulting metal–tecton reversible links. Depending on the halogen content and distribution, the simulations predicted the creation of diverse supramolecular connections such as linear and cyclic aggregates and other more complex forms. Moreover, in the case of prochiral monomers, the calculations demonstrated basic structural differences between the enantiopure and racemic assemblies in which chiral separation or mixing was observed. The obtained results can be helpful in directing the surface-assisted polymerization reactions toward organic structures with predefined size, shape, symmetry, and connectivity.

Comprehensive Review on Main Topologies of Impedance Source Inverter Used in Electric Vehicle Applications

Power electronics play a fundamental role for electric transportation, renewable energy conversion and many other industrial applications. They have the ability to help achieve high efficiency and performance in power systems. However, traditional inverters such as voltage source and current source inverters present some limitations. Consequently, many research efforts have been focused on developing new power electronics converters suitable for many applications. Compared with the conventional two-stage inverter, Z-source inverter (ZSI) is a single-stage converter with lower design cost and high efficiency. It is a power electronics circuit of which the function is to convert DC input voltage to a symmetrical AC output voltage of desired magnitude and frequency. Recently, ZSIs have been widely used as a replacement for conventional two-stage inverters in the distributed generation systems. Several modifications have been carried out on ZSI to improve its performance and efficiency. This paper reviews the-state-of-art impedance source inverter main topologies and points out their applications for multisource electric vehicles. A concise review of main existing topologies is presented. The basic structural differences, advantages and limitations of each topology are illustrated. From this state-of-the-art review of impedance source inverters, the embedded quasi-Z-source inverter presents one of the promising architectures which can be used in multisource electric vehicles, with better performance and reliability. The utilization of this new topology will open the door to several development axes, with great impact on electric vehicles (EVs).

Impact of mechanical vibrations introduced by up blasting on the structure and hardness of welds on P235GH steel during MAG welding process

This article discusses the effects of surfacing with the introduction of mechanical vibrations into the material using shot blasting. It does not require a rigid attachment of the vibrating system to the base material, and vibrations are introduced as a result of supplying energy of collision of the shot with the parent material. The effect of introducing mechanical vibrations through shot blasting during welding of P235GH steel on the structure and hardness of obtained structures was described. Comparative results of tests revealing the basic differences in the structural structure and hardness of reached welds without shot blasting and with its participation were presented. As a result of the conducted research, differences in the structural structure of the welds were shown and it was shown that shot blasting is an effective and alternative method of introducing mechanical vibrations supporting welding processes.

Quantum process tomography via optimal design of experiments

Quantum process tomography --- a primitive in many quantum information processing tasks --- can be cast within the framework of the theory of design of experiment (DoE), a branch of classical statistics that deals with the relationship between inputs and outputs of an experimental setup. Such a link potentially gives access to the many ideas of the rich subject of classical DoE for use in quantum problems. The classical techniques from DoE cannot, however, be directly applied to the quantum process tomography due to the basic structural differences between the classical and quantum estimation problems. Here, we properly formulate quantum process tomography as a DoE problem, and examine several examples to illustrate the link and the methods. In particular, we discuss the common issue of nuisance parameters, and point out interesting features in the quantum problem absent in the usual classical setting.

Extraction of Useful Information Content From Noisy Signals Based on Structural Affinity of Clustered TFDs’ Coefficients

This paper proposes an automatic method for extraction of useful information content from time-frequency distributions of nonstationary signals heavily corrupted by additive noise. The proposed method, which does not require prior knowledge of the signal, initially performs a one-dimensional clustering of the time-frequency distribution aimed at segmenting it into a fixed number of classes. This procedure points out basic structural differences of noise and signal components (i.e., useful information) in the time-frequency plane. In fact, noise presents a flat spectrum with large time-frequency supports, while signal components are narrow energy ridges. The time-frequency supports are estimated for each of the obtained classes and used as input for an algorithm aimed at discriminating “noise” affine classes, containing mainly non-zero coefficients located outside the components time-frequency supports, from “useful information” affine classes, containing mainly coefficients inside time-frequency supports of the signal components. Simulations show the superiority of the proposed algorithm, mainly in terms of error rate reduction of classified time-frequency coefficients, compared to hard amplitude thresholding methods, as well as to a recently proposed method for information content extraction based on adaptive thresholding, which is also outperformed in terms of computational complexity and execution time (by up to 43 and 28 times, respectively).

Ein Diskurs zur Übersetzbarkeit der lyrischen Dichtung im Hinblick auf Rückerts Idee der Weltliteratur

There are many strategies and methods for translating texts of various genres. There are also strategies that are particularly useful for the translation of scientific Texts. When it comes to the translation of literary texts however there are plenty of thoughts, strategies, and methods that are proposed and which provoke a huge disagreement in this area. There is, particularly, a disagreement with regard to the translation of lyric poetry. Many critics and translation theorists agree that in the translation of lyric poetry (and generally in translation of literature texts) one should transfer, on the one hand, the style and the creative power of the author of the source language to the target language and, on the other hand, should meet the expectations of readers of the target language. They differ however over which strategy or method should be used in order to achieve this goal. When considering the translation of literature texts, and particularly the translation of lyric poetry, the spirit of the author and all existent relationships between form and contents should be transferred in the translation, since they have a close relationship with the spirit of the source language and thought of the author. The possibility of achieving this is however somewhat dubious because of the basic structural differences between the source language and the target language; and also because of those differences that may be between the content of the two mentioned languages. The following paper is based on the explanation of Rueckert’s idea of “world literature”, which is related to his thought about the transfer of the spirit of literature of the source language and the transfer of both form and contents. The paper seeks to answers this question: regarding the differences in the relationships of form and contents between the source language, Persian, and the German language, how can the spirit and content of Hafiz' lyrics be best transferred to the target language. It examines the structural and content differences between the Persian and German Languages and it illustrates the strategies and methods Rueckert uses to transfer the spirit and content of the poems of Hafiz to the German language.

The effects of feeding mixed tocopherol oil on whole-blood respiratory burst and neutrophil immunometabolic-related gene expression in lactating dairy cows

The 4 major tocopherol isoforms differ in their biochemical reactivity and cellular effects due to basic chemical structural differences. Alpha-tocopherol has been well studied regarding effects on bovine polymorphonuclear leukocyte (PMN) function and its involvement in respiratory burst. However, no studies to date have identified the effects of supplementing a mixed tocopherol oil (Tmix) particularly enriched in non-α tocopherol isoforms (i.e., γ- and δ-isoforms) on fundamental immunometabolic changes in dairy cows. Therefore, the objectives of this study were to determine whether short-term feeding of vegetable oil-derived Tmix alters specific biomarkers of metabolism, whole-blood leukocyte populations, respiratory burst, immunometabolic-related gene expression of PMN, or gene expression of isolated PMN when challenged with lipopolysaccharides (LPS). Clinically healthy multiparous lactating Holstein cows (n = 12; 179 ± 17 d in milk, 40.65 ± 3.68 kg of milk yield) were fed Tmix (620 g/d) for 7 consecutive days. Jugular blood (EDTA anticoagulant) was collected from all cows on d 0 before treatment initiation and again on d 7 after Tmix feeding. Total stimulated respiratory burst activity (RBA) and leukocyte populations were assessed in whole blood, and tocopherol isoform concentrations, metabolites, and hormones were measured in plasma. For gene expression analysis, isolated PMN from cows before and after Tmix feeding were incubated with LPS at a final concentration of either 0.0 or 1.5 µg/mL. Feeding of Tmix for 7 d increased the concentrations of α- and γ-tocopherol. The Tmix did not alter plasma insulin but decreased cholesterol. The Tmix did not alter whole-blood RBA or the leukocyte populations. The LPS challenge increased the expression of proinflammatory genes TNFA and IL6. However, Tmix treatment did not alter the patterns of LPS-affected expression of genes (e.g., TNFA, ITGB2, PPARA, and RXRA) associated with the immune or metabolic response. In conclusion, short-term feeding of Tmix may have no negative effect on animal health as Tmix increased α- and γ-tocopherol concentrations in blood and did not impair whole-blood RBA or alter leukocyte populations. The data provide further support that the α- and γ-tocopherol isoforms do not interfere with normal immune or metabolic function.

Ein Diskurs zur Übersetzbarkeit der lyrischen Dichtung im Hinblick auf Rückerts Idee der Weltliteratur

Abstract There are many strategies and methods for translating texts of various genres. There are also strategies that are particularly useful for the translation of scientific Texts. When it comes to the translation of literary texts however there are plenty of thoughts, strategies, and methods that are proposed and which provoke a huge disagreement in this area. There is, particularly, a disagreement with regard to the translation of lyric poetry. Many critics and translation theorists agree that in the translation of lyric poetry (and generally in translation of literature texts) one should transfer, on the one hand, the style and the creative power of the author of the source language to the target language and, on the other hand, should meet the expectations of readers of the target language. They differ however over which strategy or method should be used in order to achieve this goal. When considering the translation of literature texts, and particularly the translation of lyric poetry, the spirit of the author and all existent relationships between form and contents should be transferred in the translation, since they have a close relationship with the spirit of the source language and thought of the author. The possibility of achieving this is however somewhat dubious because of the basic structural differences between the source language and the target language; and also because of those differences that may be between the content of the two mentioned languages. The following paper is based on the explanation of Rueckert’s idea of “world literature”, which is related to his thought about the transfer of the spirit of literature of the source language and the transfer of both form and contents. The paper seeks to answers this question: regarding the differences in the relationships of form and contents between the source language, Persian, and the German language, how can the spirit and content of Hafiz' lyrics be best transferred to the target language. It examines the structural and content differences between the Persian and German Languages and it illustrates the strategies and methods Rueckert uses to transfer the spirit and content of the poems of Hafiz to the German language.

A local entropy-based algorithm for information content extraction from time–frequency distributions of noisy signals

In this paper, an automatic adaptive method for identification and separation of the useful information content, from the background noise of time–frequency distributions (TFD) of multicomponent nonstationary signals, is presented. The method is based on an initial segmentation of the TFD information content by the K-means clustering algorithm, that partitions the initial data set in order to obtain K classes containing elements with similar amplitudes. It is shown that the local Rényi entropy (LRE) can accurately distinguish classes containing noise from classes with the useful information content, as a consequence of their basic structural differences in the time–frequency plane. Simulations are run to compare the performance of the proposed adaptive algorithm for blind separation of useful information from background noise (i.e. blind amplitude threshold) and non-adaptive (hard) amplitude TFD threshold procedures. Simulation results indicate that the proposed method performs better or closely to the best of five blindly chosen hard thresholds. The limitation of efficient hard-thresholding is the need of previous knowledge of the signal's structure and SNR or visual evaluation.

Όψεις των επαγγελματικών συνταξιοδοτικών συστημάτων στην Ευρώπη: μια βιβλιογραφική επισκόπηση

<p>Public pension systems face due to<br />demographic changes signifi cant challenges<br />that lead to reforms and to the need to reexamine<br />of the basic priorities and policy<br />instruments in relation to pensions. One of<br />the most important aspects of reforms has<br />been the development and strengthening of<br />occupational pension funds. Besides their<br />basic characteristics, occupational pension<br />funds present basic structural differences<br />between EU countries. The present article<br />seeks to highlight these differences and the<br />basic characteristics in a variety of member<br />states.</p>

Single source single-commodity stochastic network design

Stochastics affects the optimal design of a network. This paper examines the single-source single-commodity stochastic network design problem. We characterize the optimal designs under demand uncertainty and compare with the deterministic counterparts to outline the basic structural differences. We do this partly as a basis for developing better algorithms than are available today, partly to simply understand what constitutes robust network designs.

Conformational Changes in the Selectivity Filter of the Open-State KcsA Channel: An Energy Minimization Study

Potassium channels switch between closed and open conformations and selectively conduct K + ions. There are at least two gates. The TM2 bundle at the intracellular site is the primary gate of KcsA, and rearrangements at the selectivity filter (SF) act as the second gate. The SF blocks ion flow via an inactivation process similar to C-type inactivation of voltage-gated K + channels. We recently generated the open-state conformation of the KcsA channel. We found no major, possibly inactivating, structural changes in the SF associated with this massive inner-pore rearrangement, which suggests that the gates might act independently. Here we energy-minimize the open state of wild-type and mutant KcsA, validating in silico structures of energy-minimized SFs by comparison with crystallographic structures, and use these data to gain insight into how mutation, ion depletion, and K + to Na + substitution influence SF conformation. Both E71 or D80 protonations/mutations and the presence/absence of protein-buried water molecule(s) modify the H-bonding network stabilizing the P-loops, spawning numerous SF conformations. We find that the inactivated state corresponds to conformations with a partially unoccupied or an entirely empty SF. These structures, involving modifications in all four P-loops, are stabilized by H-bonds between amide H and carbonyl O atoms from adjacent P-loops, which block ion passage. The inner portions of the P-loops are more rigid than the outer parts. Changes are localized to the outer binding sites, with innermost site S4 persisting in the inactivated state. Strong binding by Na + locally contracts the SF around Na +, releasing ligands that do not participate in Na + coordination, and occluding the permeation pathway. K + selectivity primarily appears to arise from the inability of the SF to completely dehydrate Na + ions due to basic structural differences between liquid water and the “quasi-liquid” SF matrix.

Ultrastructures and strain comparison of under-glycosylated scrapie prion fibrils

Prions, composed primarily of misfolded, often fibrillar, polymers of prion protein, have poorly understood structures. Heavy surface glycosylation may obscure visualization of their fibrillar cores, so we purified severely under-glycosylated prion protein fibrils from scrapie-infected transgenic mice expressing anchorless prion protein. Using electron and atomic force microscopy, we obtained dimensions and morphological information about prion protein core protofilaments which variably intertwined to form scrapie fibrils. Occasional isolated protofilaments were observed, suggesting that the lateral association of protofilaments is neither essential nor invariant in prion protein polymerization. Strain comparisons suggested basic structural differences; ME7 and 22L fibrils contained thinner protofilaments, 22L fibrils preferred left-handed twists, and 22L fibril periodicities averaged 106nm per half-turn, compared with 64 and 66nm for RML and ME7 fibrils, respectively. The strains displayed overlapping fibril morphologies, providing evidence that prion fibril morphology is influenced, but not dictated, by strain-dependent differences in protofilament structure. These measurements of the amyloid core of scrapie fibrils should aid development of models of prion structure and strain determination.

THE ROLE OF –(s)I IN TURKISH INDEFINITE NOMINAL COMPOUNDS

This paper intends to clarify the distinction between the third person possessive suffix -(s)I attached to nouns to indicate possession and the compound marker, CM, (s)I used to construct lexicalized nominal compounds by stating their basic semantic and structural differences. To demonstrate the lexicalizing effect of the CM attached to nominal compounds, fifty native Turkish speakers irrespective of age, gender, and educational background were administered a questionnaire. In this questionnaire some nominal compounds, either the head or the modifier parts of which were imparted as blanks, were given to these subjects and they were asked to fill in the blanks with appropriate words. The aim was to find out whether some nominal compounds were more lexicalized than others. The analysis revealed that –(s)I in nominal compounds functions as a compounding marker rather than indicating possession and it has the effect of lexicalizing these compound structures

Changes in the landscape structure of the Nagara River Basin, central Japan

A watershed is a structural and functional unit of a landscape consisting of various environments and sustaining a certain biodiversity. Conservation of watershed environments is important at both the regional and the national level. As a basis for conservation management, sufficient information about landscape structure should be provided for the whole terrestrial area of a watershed. In the present study, we reconstructed the former landscape structure and elucidated the changes in land use patterns during a period of about 80 years after 1900 (late Meiji era) in the Nagara River Basin, central Japan. We used three sets of maps for the analyses: old and modern topographical maps made in 1909, 1971 and 1992 by the Geographical Agency. Each map (ca. 18 km×22 km) was divided into 400 (20×20) grid cells, according to latitude and longitude. The dimension of each grid cell was about 1 km 2 ( 0.9 km×1.1 km). In each grid cell, all land-cover types were inventoried and the most dominant one was determined to be the dominant land-cover. The relative dominance (RD), frequency (FQ) and similarity index (SI) were calculated for analyses. The relative dominance of broad-leaved forest decreased, whereas those of conifer forest and residential areas increased throughout the whole study area during the 80-year period. However, regional differences in landscape change were found. In the upriver area, the relative dominance of broad-leaved forest decreased, while that of conifer forest increased. In the mid-river area, the relative dominance of conifer forest decreased, while that of broad-leaved forest increased. In the present study, we revealed the basic regional differences in landscape structure and their changes in the Nagara River Basin. Land use history with reference to socio-economics should be considered as an important factor affecting the present landscape structure.

NMR Study of Micelles Formed by Monoalkylphosphoryl Nucleosides

An NMR investigation of aqueous micelles obtained from surfactants bearing a nucleotide head attached to a linear hexadecyl hydrocarbon chain is presented. In particular, hexadecylphosphoryl-adenosine (C16-AMP) and hexadecylphosphoryl-uridine (C16-UMP) are studied by a combination of 1H-NMR techniques such as NOESY, ROESY, and spin-lattice relaxation times. Both the intramolecular (i.e., within one surfactant monomer) and the intermolecular interactions (i.e., between neighboring surfactant molecules) are investigated. Relaxation measurements show that different groups of the surfactant molecule have distinct dynamic properties, the internal mobility decreases starting from the head group towards the Me terminal, while protons belonging to the base (which should be exposed to water) enjoy considerable freedom. The large upfield shift of the resonance of the terminal Me groups is evidence of a collective property of the micelle, an effect that, to the best of our knowledge, has not been reported so far. The micelles are studied both in water and salt solution, and the noticeable difference between the two cases is interpreted as a salt-induced stiffening effect. By mixing C16-AMP with C16-UMP, mixed micelles are obtained, i.e., micelles that contain both surfactant monomers in each aggregate; our analysis shows that a significant interaction between the two complementary aromatic bases is present. All these results allow us to draw a picture of the surfactant in the micelle in which the plane of the aromatic ring lies parallel to the surface of the micelle and towards the aqueous medium. There are no basic structural differences between C16-AMP and C16-UMP micelles or C16-AMP/C16-UMP mixed micelles.

Sonoanatomie des Schultergelenks im Wachstumsalter

It is the aim of this investigation to describe the normal ultrasonographical appearance of the glenohumeral joint in childhood. Ultrasound investigation was performed in 20 healthy children aged between 6 weeks and 19 years (median: 6 years) using 12 MHz linear probes. A dynamic examination of both shoulders was carried out. Probe positions according to standard planes were used, and attention was paid to visualise the growth regions. Ultrasound images of the periarticular soft tissue in children do not differ markedly from those in adults. However, there are basic structural differences of the epiphyseal and apophyseal regions. In the newborn period the proximal humeral epiphysis mainly consists of cartilage and changes to the adult shape after the appearance of three secondary ossification centers and growth plates. Interestingly, the chondral buds of the acromion or coracoid process offer additional imaging facilities for ultrasound examination in children. Ultrasound examination of the glenohumeral joint in children offers a more precise evaluation when compared to adults, due to the presence of additional ultrasonographical "windows" and depiction of parts of the humeral epiphysis. This imaging technique is well tolerated by children.

Science and humanities: across two cultures and into science studies.

C.P. Snow's articulation of a two-culture divide rested on a particular view of science that has been elaborated and superseded by interdisciplinary science studies. Thus, comparisons of the 'science wars' of recent years to the Snow-Leavis controversy fail to recognize basic structural differences between the two sets of debates. In this article, I present these differences and offer some views of what has changed in the intervening years.

Biophysical Characteristics of Healthy Skin and Nonlesional Skin in Atopic Dermatitis: Short-Term Effects of Ultraviolet A and B Irradiation

The present study was designed to evaluate basic differences in surface structure and viscoelastic properties of nonatopic versus atopic skin and facultative acute changes following ultraviolet irradiation. Therefore, biophysical measurements by means of profilometry and cutometry were carried out on sun-protected unaffected gluteal skin areas in both groups before and 24 h after single UVA and UVB irradiations. The results indicate that the clinically unaffected skin of patients with atopic eczema differs from normal skin in terms of increased roughness parameters, but not concerning depth of furrows or viscoelastic properties (viscosity and biological elasticity, cutometrically calculated). Single UVA irradiation with 50 J/cm² induced neither measurable changes in the skin’s surface structure nor in its viscoelastic properties in both groups after 24 h. However, irradiation with a single erythemogenic dose of 1 MED UVB was followed by a short-term significant increase in the depths of furrows and decrease in biological elasticity in normal and atopic skin, accompanied by an increase in viscosity in normal skin.

A comparative laser Raman study on TB4A, TB7A and TB10A

The basic structural differences between three thermotropic liquid crystals TB4A, TB7A and TB10A have been interpreted by analysing their Raman spectra. Three spectral regions, 925-1025, 1275-1475 and 1525-1650 cm-1, have been chosen in this context to incorporate their structural dissimilarity. The induced planarity of the backbone, as an effect of increasing chain length, has been studied by observing the changes in the respective Raman spectra of the three compounds. A tentative assignment of all the modes observed in the region 400-1700cm-1 is made in this context. The molecular conformations of the three compounds have been predicted in their solution states, and are compared with the molecular environment that exists in their liquid crystalline states. Structural disorder at the solid-SmG transition is discussed and the changes are incorporated systematically.