Electrostatic model of atomic ordering in complex perovskite alloys

We present a simple ionic model which successfully reproduces the various types of compositional long-range order observed in a large class of complex insulating perovskite alloys. The model assumes that the driving mechanism responsible for the ordering is simply the electrostatic interaction between the different ionic species. A possible new explanation for the anomalous long-range order observed in some Pb relaxor alloys, involving the proposed existence of a small amount of Pb^4+ on the B sublattice, is suggested by an analysis of the model.Comment: 4 pages, two-column style with 1 postscript figure embedded. Uses REVTEX and epsf macros. Also available at http://www.physics.rutgers.edu/~dhv/preprints/index.html#lb_orde

Ab-initio design of perovskite alloys with predetermined properties: The case of Pb(Sc_{0.5} Nb_{0.5})O_{3}

A first-principles derived approach is combined with the inverse Monte Carlo technique to determine the atomic orderings leading to prefixed properties in Pb(Sc_{0.5}Nb_{0.5})O_{3} perovskite alloy. We find that some arrangements between Sc and Nb atoms result in drastic changes with respect to the disordered material, including ground states of new symmetries, large enhancement of electromechanical responses, and considerable shift of the Curie temperature. We discuss the microscopic mechanisms responsible for these unusual effects.Comment: 5 pages with 2 postscript figures embedde

Effect of plant growth regulators on in vitro shoot multiplication of Amygdalus communis L. cv. Yaltsinki

An efficient protocol was established for in vitro shoot multiplication from apical shoot tips derived from mature trees of almond (Amygdalus communis L.) cultivars, Yaltsinki. Explants were cultured on Murashige and Skoog (1962) (MS) medium containing various concentrations of 6-benzyladenin (BA) and kinetin (kin) for shoot multiplication. Shoot multiplication was best achieved from explant on MS medium containing 30 gl-1 sucrose, 7 gl-1 agar and 1.0 mgl-1 BA. This amount of BA (1.0 mgl-1) gave the best multiple shoot formation response with an average of 16.10 shoots per explant. In addition, shoots were cultured on the media containing 1.0 mgl-1 BA and kin combined with three different auxins (0.25 and 0.5 mgl-1 of IAA, IBA and NAA) separately. It was noted that 1.0 mgl-1 BA and kin combinated with NAA had inhibitory effect on new shoot formation and no shoot formation was induced. However, explants cultivated on medium containing 1.0 mgl-1 BA and 0.5 mgl-1 IAA resulted in 11.25 shoots per explant. The effect of four different sucrose concentrations (20, 30, 40, 50 gl-1) on the multiplication of shoots was also investigated. The best shoot multiplication was obtained in MS media containing 30 gl-1 sucrose with an average of 15.40 shoots per explant

The polarizability model for ferroelectricity in perovskite oxides

This article reviews the polarizability model and its applications to ferroelectric perovskite oxides. The motivation for the introduction of the model is discussed and nonlinear oxygen ion polarizability effects and their lattice dynamical implementation outlined. While a large part of this work is dedicated to results obtained within the self-consistent-phonon approximation (SPA), also nonlinear solutions of the model are handled which are of interest to the physics of relaxor ferroelectrics, domain wall motions, incommensurate phase transitions. The main emphasis is to compare the results of the model with experimental data and to predict novel phenomena.Comment: 55 pages, 35 figure

A preliminary study in Wistar rats with enniatin : A contaminated feed

A 28-day repeated dose preliminary assay, using enniatin A naturally contaminated feed through microbial fermentation by a Fusarium tricinctum strain, was carried out employing two months-old female Wistar rats as in vivo experimental model. In order to simulate a physiological test of a toxic compound naturally produced by fungi, five treated animals were fed during twenty-eight days with fermented feed. As control group, five rats were fed with standard feed. At the 28th day, blood samples were collected for biochemical analysis and the gastrointestinal tract, liver and kidneys were removed from each rat for enniatin A detection and quantitation. Digesta were collected from stomach, duodenum, jejunum, ileum and colon. Enniatin A present in organs and in biological fluids was analyzed by liquid chromatography-diode array detector (LC-DAD) and confirmed by LC-mass spectrometry linear ion trap (MS-LIT); also several serum biochemical parameters and a histological analysis of the duodenal tract were performed. No adverse effects were found in any treated rat at the enniatin A concentration (20.91 mg/kg bw/day) tested during the 28-day experiment. Enniatin A quantitation in biological fluids ranged from 1.50 to 9.00 mg/kg, whereas in the gastrointestinal organs the enniatin A concentration ranged from 2.50 to 23.00 mg/kg. The high enniatin A concentration found in jejunum liquid and tissue points to them as an absorption area. Finally, two enniatin A degradation products were identified in duodenum, jejunum and colon content, probably produced by gut microflora

Failure Analysis of a Welded Steel Pipe at Kullar Fault Crossing.

Cheng, Yin/0000-0001-5554-9832; Karamanos, Spyros A./0000-0003-0047-9173The seismic response of a 2200-mm-diameter welded steel pipe at strike slip Kullar fault crossing in Izmit, Kocaeli during 1999 Kocaeli earthquake is investigated. The pipe was crossing the fault-line with an angle of 55 degrees and suffered leaks due to 3.0 m of right lateral movement of fault, which imposed compressive axial strain in the pipe. The backfill material of the trench was native soil which was non-homogenous (soft and stiff clay) with respect to fault line-soft material on the North side, stiff material on the South side. Field observations revealed two major wrinkles with finger width cracks and a minor wrinkle on the soft soil side of the fault. Large plastic strains and local folding were observed at wrinkles due to compressive strains. The case is known as one of the best documented fault crossing examples. The failure behavior of the Thames water pipe during 1999 Kocaeli earthquake is simulated by utilizing a 3D nonlinear continuum FE model. The numerical model considers contact surface at soil pipe interface and performs large deformation analyses of the pipe. The locations of wrinkles as well as axial displacements/rotations demands due to fault rupture are predicted. It is observed that once wrinkle initiates, strain in the pipe away from the wrinkle reduces after initial local buckling and additional shortening of the pipeline tends to accumulate at the wrinkle causing large plastic strains and rotation demands associated with fault rupture, an observation consistent with field observations and 2005 ALA guidelines. (C) 2016 Elsevier Ltd. All rights reserved.Municipality of Kocaeli Water and Sewege Systems (ISU); STREST project (EU-FP7) [603389]; ISUThis research is supported by the General Directorate of Municipality of Kocaeli Water and Sewege Systems (ISU). The methodology used in this paper is an adaptation of the STREST project (EU-FP7 no. 603389) for hydrocarbon pipelines to ISU water transmission pipe. The valuable comments received from Prof. Drs. M. Erdik and S. Akkar of KOERI and support provided by the General Directorate of ISU are gratefully acknowledged

Generate Random Image-Key using Hash Technique

Random image is very useful to be used as a source for clipping randomnesssession keys in cryptography. In this paper a new algorithm is proposed to generaterandom image .The random image is generated by mixing initialization vector withnormal digital image; the mixing process is applied in the same way as HASHtechnique. A special cryptography algorithm for generating random numbers isused to generate initialization vector. This proposed algorithm is capable ofgenerating random image that can meet security requirements of cryptographicalgorithms

Foveated image processing for faster object detection and recognition in embedded systems using deep convolutional neural networks

Object detection and recognition algorithms using deep convolutional neural networks (CNNs) tend to be computationally intensive to implement. This presents a particular challenge for embedded systems, such as mobile robots, where the computational resources tend to be far less than for workstations. As an alternative to standard, uniformly sampled images, we propose the use of foveated image sampling here to reduce the size of images, which are faster to process in a CNN due to the reduced number of convolution operations. We evaluate object detection and recognition on the Microsoft COCO database, using foveated image sampling at different image sizes, ranging from 416×416 to 96×96 pixels, on an embedded GPU – an NVIDIA Jetson TX2 with 256 CUDA cores. The results show that it is possible to achieve a 4× speed-up in frame rates, from 3.59 FPS to 15.24 FPS, using 416×416 and 128×128 pixel images respectively. For foveated sampling, this image size reduction led to just a small decrease in recall performance in the foveal region, to 92.0% of the baseline performance with full-sized images, compared to a significant decrease to 50.1% of baseline recall performance in uniformly sampled images, demonstrating the advantage of foveated sampling

Generate Animated CAPTCHA Based on Visual Cryptography Concept

CAPTCHA is a standard security technology. To date, the most commonly used are various types of visual CAPTCHAs, in which a challenge often appears as an image of distorted text that the user must decipher. The proposed scheme is used visual cryptography encryption protocol to encrypt CAPTCHA image in perfectly secure way, such that only the human visual system can easily decrypt the CAPTCHA image with animated arrangement. Numbers of blurring image process are implemented on the CAPTCHA images, to make this test difficult for current computer systems. The new animated CAPTCHA is more secure than the currentversions and easier for humans to pass

Cesarean section: requested mode of delivery?

Aim: To constitute accurate policies for reducing the cesarean section (C/S) the authors evaluated the attitudes and knowledge of health workers and public population towards the mode of delivery, C/S on demand, and delivery complications in a large population. Materials and Methods: 1,892 female volunteers in reproductive age were enrolled in the study and 589 of them were health workers. Patients were evaluated with questionnaire about their delivery mode and their answers were analyzed. Results: The overall cesarean rate of the study population was 45.4%. This rate were 51.4% and 28.2%, respectively, for the health workers and public group (p < 0.001). Medical indication ratio were 57.7% and 40.1% for the healthcare group and the public population respectively and 20.2% of health workers and 13.9% of the public group had C/S by their preference without any medical indications (p < 0.001). Conclusion: C/S rate is high in Turkey and an action plan is needed to decrease the rate. When a patient's preference towards the mode of the delivery is C/S on demand, obstetricians, in their capacity as patient advocate, should help guide their patient through the sophisticated detailed medical information toward a decision that respects both the patient's attitude and the physician's obligation to optimize the health of both the mother and the newborn