Türkiye Bilimsel ve Teknolojik Araştırma Kurumu

Vibrational dynamics of folded proteins is studied using a Gaussian model in which the protein is viewed as a network, residues representing the junctions, and the connectivity being established by a single parameter harmonic potential. Application to seven proteins showed that the local packing density plays a major role in determining the vibrational spectrum at time scales of picoseconds. At later times, the secondary structure and tertiary context of each residue comes into play. The vibrational frequencies obey a universal distribution, confirming previous normal mode analyses.

Abstract The Tethysides are a superorogenic complex flanking the Eurasian continent to the south and consisting of the Cimmerides and Alpides , products of Palaeo- and Neo-Tethys respectively. We here review their evolution, mainly on the basis of new maps showing the distribution of sutures, magmatic rocks, certain palaeobiogeographically and palaeoclimatologically significant taxa and facies, and fragments of Pan-African (900–450 Ma) orogenic system forming the basement of many Tethyside blocks. These are supplemented by palaeomagnetic data reported in the literature. A fundamental tenet of this paper is that major sutures which contain ophiolite fragments, represent tectonic sections between continental blocks where oceanic crust has been subducted. Palaeo-Tethys came into existence largely in late Carboniferous time. Coevally, it began to be consumed by both internal and peripheral subduction zones, which continued into the Permian; some of these had been inherited from pre-Tethyan times. In the later Permian, rifting subparallel with the northern margin of Gondwana Land began between the Zagros and Malaysia, separating a Cimmerian continent from N. Gondwana Land, and thus heralding the opening of Neo-Tethys and other smaller oceans that were back-arc basins of Palaeo-Tethys. This rifting possibly also extended farther west into Crete and mainland Greece. However, the North China block, Yangtze block, Huanan block, the eastern moity of the Qangtang block (North Tibet), and Annamia, all originally pieces of the end-Proterozoic-early Palaeozoic Gondwana Land, had already separated from it in pre-late Carboniferous times, possibly during the Devonian. All of these blocks, and the Cimmerian continent, were characterized by Cathaysian floral elements in late Palaeozoic time. Palaeomagnetic and palaeontological data showing the original Gondwana Land affinity of these continental blocks are supplemented by correlating late Proterozoic-early Palaeozoic Pan-African sutures, orogenic belts, and sedimentary basin fragments across Tethyside sutures. Late Permian foraminiferal provinces are related to this palaeogeographical interpretation. By Triassic times, most Cimmeride subduction zones were already in existence. The Cimmerian Continent accelerated its separation from Gondwana Land and—locally in the late Permian—began disintegrating internally along the Waser/Rushan-Pshart/Banggong Co-Nu Jiang/Mandalay ocean. By late Triassic time all of the Chinese blocks—except Lhasa-and Annamia had collided with each other and with Laurasia. The resulting enormous orogenic collage had a ‘soft cushion’ between itself and Laurasia, in the form of the enormous accretionary complex of the Songpan-Ganzi. This connection enabled Laurasian land vertebrates to reach south-east Asia by late Triassic time. In late Triassic to middle Jurassic times, most major Cimmeride collisions were completed. Widespread aridity in Central Asia occurred in late Jurassic time, probably in the rain shadow of the newly formed Cimmeride mountain wall. Neo-Tethyan subduction systems formed along the S. margin of the Cimmerides or within Neo-Tethyan oceanic lithosphere during the Jurassic. Most, if not all, were north- or east-dipping. They continued the northerly migration of the Tethyside blocks. Evolution of the Tethysides influenced the distribution of marine and terrestrial organisms, and affected sea-level changes and patterns of atmospheric circulation during much of the Mesozoic and Cainozoic. It is likely to have reflected the surface expression of a persistent trend in the large-scale convective circulation in the mantle, that continuously transported material northward into the Tethyan domain.

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A brief introduction to the fractional Fourier transform and its properties is given. Its relation to phase-space representations (time- or space-frequency representations) and the concept of fractional Fourier domains are discussed. An overview of applications which have so far received interest are given and some potential application areas remaining to be explored are noted.

In 1970, three laboratories independently made a discovery that, for aromatic fluorophores embedded into different rigid and highly viscous media, the spectroscopic properties do not conform to classical rules. The fluorescence spectra can depend on excitation wavelength, and the excited-state energy transfer, if present, fails at the "red" excitation edge. These red-edge effects were related to the existence of excited-state distribution of fluorophores on their interaction energy with the environment and the slow rate of dielectric relaxation of this environment. In these conditions the site-selection can be provided by variation of the energy of illuminating light quanta, and the behaviour of selected species can be followed as a function of time and other variables. These observations found extensive application in different areas of research: colloid and polymer science, molecular biophysics, photochemistry and photobiology. In particular, they led to the development of very productive methods of studying the dynamics of dielectric relaxations in protein and membranes, using the tryptophan emission and the emission of a variety of probes. These studies were extended to the time domain with the observation of new site-selective effects in emission intensity and anisotropy decays. They stimulated the emergence and development of cryogenic energy-selective and single-molecular techniques that became valuable tools in their own right in chemistry and biophysics research. Site-selection effects were discovered for electron-transfer and proton-transfer reactions if they depended on the dynamics of the environment. This review is focused on the progress in the field of red-edge effects, their applications and prospects.

A single-parameter harmonic Hamiltonian based on local packing density and contact topology is proposed for studying residue fluctuations in native proteins. The internal energy obeys an equipartition law, and free energy changes result from entropy fluctuations only. Frequency--wave-number maps show communication between residues involved in slow and fast modes. Fast modes are strongly localized, resulting from the geometric irregularity of the structure. Comparison with experiments shows that slow and fast modes are associated, respectively, with function and stability. Specifically, domain motions and folding cores of HIV-1 protease are accurately identified.

This is a minor bug-fix release in the 1.0.x series and includes some regression fixes and bug fixes. We recommend that all users upgrade to this version. See the full whatsnew for a list of all the changes. The release will be available on the defaults and conda-forge channels: <pre><code>conda install pandas </code></pre> Or via PyPI: <pre><code>python3 -m pip install --upgrade pandas </code></pre> Please report any issues with the release on the pandas issue tracker.

Purpose The main purpose of this paper is to investigate the direct and interactive effects of organizational support and human capital on the innovative performance of companies. Individual effects of the organizational support dimensions, namely: management support for generating and developing new business ideas, allocation of free time, convenient organizational structures concerning, in particular, decentralization level or decision‐making autonomy, appropriate use of incentives and rewards, and tolerance for trial‐and‐errors or failures in cases of creative undertakings or risky project implementations, are also to be investigated. Design/methodology/approach The study develops and tests a theoretical research model where the organizational support dimensions are the independent variables, innovative performance is the dependent variable, and the human capital has a moderating role in this relationship, via a questionnaire study covering 184 manufacturing firms in Turkey. Findings Among the individual direct effects of the dimensions of organizational support, management support for idea development and tolerance for risk taking are found to exert positive effects on innovative performance. Availability of a performance based reward system and free time have no impact on innovativeness, while work discretion has a negative one. As for the role of human capital (HC), it is found to be an important driver of innovative performance especially when the OS is limited. However, when the levels of both HC and OS are high, innovative performance does not increase any further. Originality/value Two distinct research streams, namely organizational support literature and human capital literature, have already focused on their individual impacts on the innovative performance. However, a combination of these separate streams was not tried before. The paper discusses and investigates what will happen when both positive drivers interact with each other. Moreover, it also investigates how organizational support and human capital are complementary.

This paper describes the design and construction of the MicroBooNE liquid argon time projection chamber and associated systems. MicroBooNE is the first phase of the Short Baseline Neutrino program, located at Fermilab, and will utilize the capabilities of liquid argon detectors to examine a rich assortment of physics topics. In this document details of design specifications, assembly procedures, and acceptance tests are reported.

The levels of phytochemicals (total phenols, proanthocyanidins, gallic acid + gallotannins, ellagic acid + ellagitannins, flavonoids, phenolic acids, stilbenes and phytates), fat-soluble bioactives (lipid, tocols, phytosterols, sphingolipids, carotenoids, chlorophylls and alkyl phenols) as well as natural antioxidants (nutrient and non-nutrient) present in commonly consumed twelve nuts (almond, Brazil nut, cashew, chestnut, hazelnut, heartnut, macadamia, peanut, pecan, pine nut, pistachio and walnut) are compared and reported. Recent studies adding new evidence for the health benefits of nuts are also discussed. Research findings from over 112 references, many of which have been published within last 10 years, have been compiled and reported.

The data in many disciplines such as social networks, Web analysis, etc. is link-based, and the link structure can be exploited for many different data mining tasks. In this article, we consider the problem of temporal link prediction: Given link data for times 1 through T , can we predict the links at time T + 1? If our data has underlying periodic structure, can we predict out even further in time, i.e., links at time T + 2, T + 3, etc.? In this article, we consider bipartite graphs that evolve over time and consider matrix- and tensor-based methods for predicting future links. We present a weight-based method for collapsing multiyear data into a single matrix. We show how the well-known Katz method for link prediction can be extended to bipartite graphs and, moreover, approximated in a scalable way using a truncated singular value decomposition. Using a CANDECOMP/PARAFAC tensor decomposition of the data, we illustrate the usefulness of exploiting the natural three-dimensional structure of temporal link data. Through several numerical experiments, we demonstrate that both matrix- and tensor-based techniques are effective for temporal link prediction despite the inherent difficulty of the problem. Additionally, we show that tensor-based techniques are particularly effective for temporal data with varying periodic patterns.

The development of edible films and coatings has seen remarkable growth in recent decades and is expected to have an important impact on the quality of food products in the coming years. This growth is attributed to the increasing knowledge of edible films and edible coating technology, as well as advances in material science and processing technology. Packaging is used in order to reduce synthetic packaging and can play a role as an eco-friendly biodegradable package or a protective coating on the food surface. A large amount of bio-based polymers have been used in the production of edible films and coatings. Novel sources of edible materials, as well as the novel processing techniques, are a subject of great interest due to their promising potential as innovative food packaging systems. This paper presents the concept and potential for application of new film-forming materials and management of food wastes from the fruit and vegetable industry, which can encounter problems in appropriate disposal. It summarizes the extensive knowledge about the new film-forming materials such as plant residues, flours and gums to show their protective effectiveness and suitability in various types of foods.

Abstract A new family of anthracene core, highly fluorescent emitters is synthesized which include diphenylamine hole transport end groups. Using a very simple one or two layer organic light emitting diode (OLED) structure, devices without outcoupling achieve an external quantum efficiency of 6% and photonic efficiencies of 20 cd/A. The theoretical maximum efficiency of such devices should not exceed 3.55%. Detailed photophysical characterization shows that for these anthracene based emitters 2T 1 ≤T n and so in this special case, triplet fusion can achieve a singlet production yield of 0.5. Indeed, delayed electroluminescence measurements show that triplet fusion contributes 59% of all singlets produced in these devices. This demonstrates that when triplet fusion becomes very efficient, fluorescent OLEDs even with very simple structures can approach an internal singlet production yield close to the theoretical absolute maximum of 62.5% and rival phosphorescent‐based OLEDs with the added advantage of much improved stability.

We use Global Positioning System (GPS) observations and elastic half-space models to estimate the distribution of coseismic and postseismic slip along the Izmit earthquake rupture. Our results indicate that large coseismic slip (reaching 5.7 meters) is confined to the upper 10 kilometers of the crust, correlates with structurally distinct fault segments, and is relatively low near the hypocenter. Continued surface deformation during the first 75 days after the earthquake indicates an aseismic fault slip of as much as 0.43 meters on and below the coseismic rupture. These observations are consistent with a transition from unstable (episodic large earthquakes) to stable (fault creep) sliding at the base of the seismogenic zone.

Background: An important aspect of the &amp;amp;quot;description&amp;amp;quot; of a variable is the shape of its distribution, which tells you the frequency of values from different ranges of the variable. Typically, as most of the statistical tests are based on the normality assumption, a researcher is interested in how well the distribution can be approximated by the normal distribution. Unless there are extreme violations of the normality assumptions, approved statistical tests usually provide accurate results. Although simple descriptive statistics can provide some information relevant to this issue, more precise information can be obtained by performing one of the tests of normality to determine whether the sample comes from a normally distributed population or not. Aim: Lilliefors corrected Kolmogorov-Smirnov, Shapiro-Wilk, D&amp;amp;apos;Agostino Pearson and Jarqua-Bera tests were aimed to be compared in terms of Type I error and power of the tests. Materials and Methods: The simulation was run 1000 times for 23 different sample sizes and for 8 different distributions. Lilliefors corrected Kolmogorov-Smirnov, Shapiro-Wilk, D&amp;amp;apos;Agostino Pearson and Jarqua-Bera tests were compared in terms of Type I error and power of the tests. Results: The most powerful results for normal distributions were given by the Jarqua-Bera and for non-normal distributions by the Shapiro-Wilk test. Conclusions: As it had the lowest Type I error rate, the Jarqua-Bera test was superior for normal and standard normal distributions. For nonnormal distributions, achieving sufficient power at smaller sample sizes, the Shapiro-Wilk was the most powerful.

Excited-state intramolecular proton transfer (ESIPT) in 3-hydroxyflavone dyes allows us to record, in addition to common spectroscopic parameters, the positions of absorption (νabs) and emission (νN*) maxima, two new parameters: the position of the emission maximum of the ESIPT product T* state (νT*) and the intensity ratio of the two emission bands (IN*/IT*). An attempt was made to find a correlation between these parameters and physicochemical characteristics of microenvironment: polarity f(ε), electronic polarizability f(n) and H-bond donor ability. A detailed spectroscopic study of 4′-diethylamino-3-hydroxyflavone in a set of 21 representative solvents demonstrates that the Stokes shift of the N* band (νabs − νN*) correlates strongly with the Lippert function L = f(ε) − f(n), and this correlation does not depend on the effects of intermolecular H-bonding, while the correlation of log(IN*/IT*) with polarity f(ε) can be represented by linear functions that are different for protic and aprotic environments. Cross-correlation analysis of the spectroscopic parameters provides criteria to distinguish specific (H-bonding and other) from universal probe interactions with the environment. We suggest an algorithm, which uses four spectroscopic parameters νabs, νN*, νT* and log(IN*/IT*) to provide a simultaneous estimation of three microenvironment characteristics: f(ε), f(n) and H-bond donor ability. An application of this algorithm in the studies of binary solvent mixtures, reverse micelles and binding sites of proteins demonstrates the power of this approach and suggests a unique possibility to develop a new generation of fluorescence probes and labels in the 3-hydroxyflavone family for studying complex microheterogeneous systems in physical chemistry, colloid chemistry and the biological sciences.

Amines are well-known for their reversible reactions with CO2, which make them ideal for CO2 capture from several gas streams, including flue gas. In this respect, selective CO2 absorption by aqueous alkanolamines is the most mature technology but the process is energy intensive and has also corrosion problems. Both disadvantages can be diminished to a certain extent by chemical adsorption of CO2 selectively. The most important element of the chemical adsorption of CO2 involves the design and development of a suitable adsorbent which consist of a porous support onto which an amine is attached or immobilized. Such an adsorbent is often called as solid amine sorbent. This review covers solid amine-based studies which are developed and published in recent years. First, the review examines several different types of porous support materials, namely, three mesoporous silica (MCM-41, SBA-15 and KIT-6) and two polymeric supports (PMMA and PS) for CO2 adsorption. Emphasis is given to the synthesis, modifications and characterizations -such as BET and PXRD data-of them. Amination of these supports to obtain a solid amine sorbent through impregnation or grafting is reviewed comparatively. Focus is given to the adsorption mechanisms, material characteristics, and synthesis methods which are discussed in detail. Significant amount of original data are also presented which makes this review unique. Finally, relevant CO2 adsorption (or equilibrium) capacity data, and cyclic adsorption/desorption performance and stability of important classes of solid amine sorbents are critically reviewed. These include severa PEI or TEPA impregnated adsorbents and APTES-grafted systems.

Earthquake scarps associated with recent historical events have been found on the floor of the Sea of Marmara, along the North Anatolian Fault (NAF). The MARMARASCARPS cruise using an unmanned submersible (ROV) provides direct observations to study the fine‐scale morphology and geology of those scarps, their distribution, and geometry. The observations are consistent with the diversity of fault mechanisms and the fault segmentation within the north Marmara extensional step‐over, between the strike‐slip Ganos and Izmit faults. Smaller strike‐slip segments and pull‐apart basins alternate within the main step‐over, commonly combining strike‐slip and extension. Rapid sedimentation rates of 1–3 mm/yr appear to compete with normal faulting components of up to 6 mm/yr at the pull‐apart margins. In spite of the fast sedimentation rates the submarine scarps are preserved and accumulate relief. Sets of youthful earthquake scarps extend offshore from the Ganos and Izmit faults on land into the Sea of Marmara. Our observations suggest that they correspond to the submarine ruptures of the 1999 Izmit (Mw 7.4) and the 1912 Ganos (Ms 7.4) earthquakes. While the 1999 rupture ends at the immediate eastern entrance of the extensional Cinarcik Basin, the 1912 rupture appears to have crossed the Ganos restraining bend into the Sea of Marmara floor for 60 km with a right‐lateral slip of 5 m, ending in the Central Basin step‐over. From the Gulf of Saros to Marmara the total 1912 rupture length is probably about 140 km, not 50 km as previously thought. The direct observations of submarine scarps in Marmara are critical to defining barriers that have arrested past earthquakes as well as defining a possible segmentation of the contemporary state of loading. Incorporating the submarine scarp evidence modifies substantially our understanding of the current state of loading along the NAF next to Istanbul. Coulomb stress modeling shows a zone of maximum loading with at least 4–5 m of slip deficit encompassing the strike‐slip segment 70 km long between the Cinarcik and Central Basins. That segment alone would be capable of generating a large‐magnitude earthquake (Mw 7.2). Other segments in Marmara appear less loaded.

Zeolites are crystalline hydrated aluminosilicates with remarkable physical and chemical properties, which include losing and receiving water in a reverse way, adsorbing molecules that act as molecular sieves, and replacing their constituent cations without structural change. The commercial production of natural zeolites has accelerated during the last 50 years. The Structure Commission of the International Zeolite Association recorded more than 200 zeolites, which currently include more than 40 naturally occurring zeolites. Recent findings have supported their role in stored-pest management as inert dust applications, pesticide and fertilizer carriers, soil amendments, animal feed additives, mycotoxin binders and food packaging materials. There are many advantages of inert dust application, including low cost, non-neurotoxic action, low mammalian toxicity and safety for human consumption. The latest consumer trends and government protocols have shifted toward organic origin materials to replace synthetic chemical products. In the present review, we summarize most of the main uses of zeolites in food and agruculture, along with the with specific paradigms that illustrate their important role. © 2017 Society of Chemical Industry.

Abstract Tensor decompositions are higher‐order analogues of matrix decompositions and have proven to be powerful tools for data analysis. In particular, we are interested in the canonical tensor decomposition, otherwise known as CANDECOMP/PARAFAC (CP), which expresses a tensor as the sum of component rank‐one tensors and is used in a multitude of applications such as chemometrics, signal processing, neuroscience and web analysis. The task of computing CP, however, can be difficult. The typical approach is based on alternating least‐squares (ALS) optimization, but it is not accurate in the case of overfactoring. High accuracy can be obtained by using nonlinear least‐squares (NLS) methods; the disadvantage is that NLS methods are much slower than ALS. In this paper, we propose the use of gradient‐based optimization methods. We discuss the mathematical calculation of the derivatives and show that they can be computed efficiently, at the same cost as one iteration of ALS. Computational experiments demonstrate that the gradient‐based optimization methods are more accurate than ALS and faster than NLS in terms of total computation time. Copyright © 2011 John Wiley &amp; Sons, Ltd.