Hybrid solid state qubits: the powerful role of electron spins

We review progress on the use of electron spins to store and process quantum information, with particular focus on the ability of the electron spin to interact with multiple quantum degrees of freedom. We examine the benefits of hybrid quantum bits (qubits) in the solid state that are based on coupling electron spins to nuclear spin, electron charge, optical photons, and superconducting qubits. These benefits include the coherent storage of qubits for times exceeding seconds, fast qubit manipulation, single qubit measurement, and scalable methods for entangling spatially separated matter-based qubits. In this way, the key strengths of different physical qubit implementations are brought together, laying the foundation for practical solid-state quantum technologies.Comment: 54 pages, 7 figure

Regenerating Rat Liver: Correlations Between Estrogen Receptor Localization and Deoxyribonucleic Acid Synthesis

Estrogen receptor activity was quantitated in the cytosol and nucleus of normal rat liver and in regenerating rat liver at several time intervals after 75% hepatectomy. Cytosolic estradiol binding in regenerating liver decreases at 12, 24, and 48 h after hepatectomy and at 48 h is 30% of that in normal rat liver. Nuclear estrogen binding 48 h after surgery is elevated fivefold over normal values. No alterations in affinity of the receptor for estrogen have been observed. Specificity studies indicate that the estrogen receptors from both normal and regenerating liver were similar and are highly specific for estrogens. These changes in cellular distribution of receptors parallel increases in nuclear deoxyribonucleic acid synthesis and mitotic indices in the liver. © 1984, American Gastroenterological Association. All rights reserved

Estrogen Binding Protein Activity in Morris Hepatoma 7777 Compared With Normal Rat Liver

Estrogen binding protein activities were determined in the cytosol from adult male Buffalo rat liver and Morris hepatoma 7777. Estrogen receptors were prepared using the protamine sulfate precipitation technique of Chamness. The ability of various unlabeled steroids competing with [3H]estradiol was examined to establish the binding specificity. Estradiol binding in Morris hepatoma 7777 cytosol was greatly decreased compared with that present in hepatic cytosol prepared from normal rat liver. The receptor concentration expressed as femtomoles per milligram of cytoplasmic protein was 31.1 ± 2.9 SD for normal rat liver and 0.41 ± 0.88 SD for the hepatoma. Gel filtration chromatography revealed the presence of an estrogen binder in hepatoma cytosol which was not present in either normal liver or in the protamine sulfate precipitates of hepatoma cytosol. The molecular weight, binding specificity, and precipitation of this protein by specific antiserum suggests that it is α-fetoprotein. © 1984, American Gastroenterological Association. All rights reserved

Characterization of cortex and white matter injury in a mild hypoxic-ischemic neonatal rat mode by diffusion tensor MR imaging

Animal Studies: Diffusion & Perfusion - Poster presentationWe evaluated hypoxic-ischemic (HI) induced cortex and white matter (WM) damage in a mild HI neonatal rat model at 24h post HI by diffusion tensor MR imaging (DTI) and correlated the DTI indices with histological evaluations. Results showed that significantly decreased FA and ¦Ë// reflected HI induced astrogliosis in the injured cortex, whereas significantly decreased FA with increased ¦Ë¡Í indicated dysmyelination in the WM. Our results demonstrated that early mild HI induced cortex and WM damage could be reflected by DTI indices and these may be potentially useful biomarkers to non-invasively monitor mild HI induced neonatal brain damage.published_or_final_versionThe 17th Scientific Meeting & Exhibition of the International Society of Magnetic Resonance in Medicine (ISMRM), Honolulu, HI., 18-24 April 2009. In Proceedings of ISMRM 17th Scientific Meeting & Exhibition, 2009, p. 359

Relativistic scattering of a fast spinning neutron star by a massive black hole

The orbital dynamics of fast spinning neutron stars encountering a massive bh with unbounded orbits are investigated using the quadratic-in-spin mpd formulation. We consider the motion of the spinning neutron stars with astrophysically relevant speed in the gravity field of the BH. For such slow-speed scattering, the hyperbolic orbits followed by these neutron stars all have near the e = 1 eccentricity, and have distinct properties compared with those of e ≫ 1. We have found that compared with geodesic motion, the spin-orbit and spin-spin coupling will lead to a variation of scattering angles at spatial infinity, and this variation is more prominent for slow-speed scattering than fast-speed scattering. Such a variation leads to an observable difference in pulse-arrival-time within a few hours of observation, and up to a few days or months for larger BH masses or longer spinning periods. Such a relativistic pulsar-BH system also emits a burst of gravitational waves (GWs) in the sensitivity band of LISA, and for optimal settings, can be seen up to 100 Mpc away. A radio follow up of such a GW burst with SKA or FAST will allow for measuring the orbital parameters with high accuracy and testing the predictions of gr

Response of Laser-Induced Thermal Lens Effect at Solid Surface

Recently Kuo et al. [1,2] and Satio et al.[3] presented the surface-thermal lens (STL) technique, this novel photothermal deformation technique has attracted great attention because it is a highly sensitive, noncontact and nondestructive measurement[4–6]. In this technique, a modulated pump beam is focused on the sample surface to produce the surface deformation and a cw probe beam is incident at the deformation region. Differing from the conventional photothermal deformation techniques, the spot size of the probe beam at the sample surface is much larger than the pump beam one. Then the probe beam reflected from the surface produces a diffraction pattern at the detection plane. More recently, STL technique has been successfully applied to study the temperature dependence of the thermal conductivity of semiconductor materials[5], weak absorption of optical thin films[6] and characterization of the solid materials[7,8]. However, the mechanism of STL phenomena has not been completely understood. Most theoretical models took no account of the influence of the air-thermal lens (ATL), although some experiment showed that the air significantly affected the detected diffraction pattern[2]. In addition, it is necessary to characterize frequency responses of signals because the response is used to determine the thermal property of the solid materials[5]

Metabolism of 2-Chloro-4-Nitrophenol in a Gram Negative Bacterium, Burkholderia sp. RKJ 800

A 2-Chloro-4-nitrophenol (2C4NP) degrading bacterial strain designated as RKJ 800 was isolated from a pesticide contaminated site of India by enrichment method and utilized 2C4NP as sole source of carbon and energy. The stoichiometric amounts of nitrite and chloride ions were detected during the degradation of 2C4NP. On the basis of thin layer chromatography, high performance liquid chromatography and gas chromatography-mass spectrometry, chlorohydroquinone (CHQ) and hydroquinone (HQ) were identified as major metabolites of the degradation pathway of 2C4NP. Manganese dependent HQ dioxygenase activity was observed in the crude extract of 2C4NP induced cells of the strain RKJ 800 that suggested the cleavage of the HQ to γ-hydroxymuconic semialdehyde. On the basis of the 16S rRNA gene sequencing, strain RKJ 800 was identified as a member of genus Burkholderia. Our studies clearly showed that Burkholderia sp. RKJ 800 degraded 2-chloro-4-nitrophenol via hydroquinone pathway. The pathway identified in a gram negative bacterium, Burkholderia sp. strain RKJ 800 was differed from previously reported 2C4NP degradation pathway in another gram-negative Burkholderia sp. SJ98. This is the first report of the formation of CHQ and HQ in the degradation of 2C4NP by any gram-negative bacteria. Laboratory-scale soil microcosm studies showed that strain RKJ 800 is a suitable candidate for bioremediation of 2C4NP contaminated sites

Solving kk-means on High-dimensional Big Data

In recent years, there have been major efforts to develop data stream algorithms that process inputs in one pass over the data with little memory requirement. For the $k$-means problem, this has led to the development of several $(1+\varepsilon)$-approximations (under the assumption that $k$ is a constant), but also to the design of algorithms that are extremely fast in practice and compute solutions of high accuracy. However, when not only the length of the stream is high but also the dimensionality of the input points, then current methods reach their limits. We propose two algorithms, piecy and piecy-mr that are based on the recently developed data stream algorithm BICO that can process high dimensional data in one pass and output a solution of high quality. While piecy is suited for high dimensional data with a medium number of points, piecy-mr is meant for high dimensional data that comes in a very long stream. We provide an extensive experimental study to evaluate piecy and piecy-mr that shows the strength of the new algorithms.Comment: 23 pages, 9 figures, published at the 14th International Symposium on Experimental Algorithms - SEA 201

Phase transformation behaviour of porous NiTi alloys fabricated by capsule-free hot isostatic pressing

Differential scanning calorimetry (DSC) was used to characterize the phase transformation behaviour of porous Ni50Ti50 alloys fabricated by capsule-free hot isostatic pressing (CF-HIP) with different cold compaction pressures. Experimental results reveal that a multi-stage martensitic transformation (MST) exists in the sintered porous NiTi alloys on cooling while the reverse transformation upon heating is either a single or two-stage phase transformation. The DSC thermal analysis indicates that the cold compaction pressure has great effect on the subsequent transformation temperatures. Generally, the phase transformation temperatures of porous NiTi alloys with lower cold compaction pressure are higher than those compacted with higher pressure. With increase in the annealing time, the transformation temperatures increase quickly when the cold compaction pressure was 150MPa. On the other hand, the transformation temperatures change only slightly when the cold compaction pressure was varied from 300MPa to 400MPa. These phenomena can be attributed to the combined effect of larger plastic deformation with higher dislocations density produced by cold compaction and the precipitation of the second phase in the porous NiTi alloys.published_or_final_versio

Corrosion products and mechanism on NiTi shape memory alloy in physiological environment

Despite many investigations on the corrosion behavior of NiTi shape memory alloys (SMAs) in various simulated physiological solutions by electrochemical measurements, few have reported detailed information on the corrosion products. In the present study, the structure and composition of the corrosion products on NiTi SMAs immersed in a 0.9% NaCl physiological solution are systematically investigated by scanning electron microscopy (SEM), x-ray energy dispersion spectroscopy (EDS), and x-ray photoelectron spectroscopy (XPS). It is found that attack by Cl - results in nickel being released into the solution and decrease in the local nickel concentration at the pitting sites. The remaining Ti reacts with dissolved oxygen from the solution to form titanium oxides. After longterm immersion, the corrosion product layer expands over the entire surface and XPS reveals that the layer is composed of TiO 2, Ti 2O3, and TiO with relatively depleted Ni. The growth rate of the corrosion product layer decreases with immersion time, and the corrosion product layer is believed to impede further corrosion and improve the biocompatibility of NiTi alloy in a physiological environment. It is found that the release rate of nickel is related to the surface structure of the corrosion product layer and immersion time. A corrosion mechanism is proposed to explain the observed results. © 2010 Materials Research Society.published_or_final_versio