2,997 research outputs found

    Two-tape finite automata with quantum and classical states

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    {\it Two-way finite automata with quantum and classical states} (2QCFA) were introduced by Ambainis and Watrous, and {\it two-way two-tape deterministic finite automata} (2TFA) were introduced by Rabin and Scott. In this paper we study 2TFA and propose a new computing model called {\it two-way two-tape finite automata with quantum and classical states} (2TQCFA). First, we give efficient 2TFA algorithms for recognizing languages which can be recognized by 2QCFA. Second, we give efficient 2TQCFA algorithms to recognize several languages whose status vis-a-vis 2QCFA have been posed as open questions, such as Lsquare={anbn2nN}L_{square}=\{a^{n}b^{n^{2}}\mid n\in \mathbf{N}\}. Third, we show that {anbnknN}\{a^{n}b^{n^{k}}\mid n\in \mathbf{N}\} can be recognized by {\it (k+1)(k+1)-tape deterministic finite automata} ((k+1)(k+1)TFA). Finally, we introduce {\it kk-tape automata with quantum and classical states} (kkTQCFA) and prove that {anbnknN}\{a^{n}b^{n^{k}}\mid n\in \mathbf{N}\} can be recognized by kkTQCFA.Comment: 25 page

    Chalcogenide phase change materials for nanoscale switching

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    Since the demonstration of threshold switching in chalcogenide alloys over forty five years ago, phase change materials have been extensively investigated for switching and data storage applications. Phase change switching is based on the reversible change between crystalline and amorphous states of a material and in many chalcogenides this change of state takes place in nanoseconds

    Smooth free involution of HCP3H{\Bbb C}P^3 and Smith conjecture for imbeddings of S3S^3 in S6S^6

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    This paper establishes an equivalence between existence of free involutions on HCP3H{\Bbb C}P^3 and existence of involutions on S6S^6 with fixed point set an imbedded S3S^3, then a family of counterexamples of the Smith conjecture for imbeddings of S3S^3 in S6S^6 are given by known result on HCP3H{\Bbb C}P^3. In addition, this paper also shows that every smooth homotopy complex projective 3-space admits no orientation preserving smooth free involution, which answers an open problem [Pe]. Moreover, the study of existence problem for smooth orientation preserving involutions on HCP3H{\Bbb C}P^3 is completed.Comment: 10 pages, final versio

    Crystal Structure, Infrared Spectra, and Microwave Dielectric Properties of Temperature-Stable Zircon-Type (Y,Bi)VO<inf>4</inf> Solid-Solution Ceramics

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    A series of (Bi 1-x Y x )VO 4 (0.4 ≤ x ≤ 1.0) ceramics were synthesized using the traditional solid-state reaction method. In the composition range of 0.4 ≤ x ≤ 1.0, a zircon-type solid solution was formed between 900 and 1550 °C. Combined with our previous work (scheelite monoclinic and zircon-type phases coexist in the range of x < 0.40), a pseudobinary phase diagram of BiVO 4 -YVO 4 is presented. As x decreased from 1.0 to 0.40, the microwave permittivity (ϵ r ) of (Bi 1-x Y x )VO 4 ceramics increased linearly from 11.03 to 30.9, coincident with an increase in the temperature coefficient of resonant frequency (TCF) from -61.3 to +103 ppm/°C. Excellent microwave dielectric properties were obtained for (Bi 0.3 Y 0.7 )VO 4 sintered at 1025 °C and (Bi 0.2 Y 0.8 )VO 4 sintered at 1075 °C with ϵ r ∼ 19.35, microwave quality factor (Qf) ∼ 25 760 GHz, and TCF ∼ +17.8 ppm/°C and ϵ r ∼ 16.3, Qf ∼ 31 100 GHz, and TCF ∼ -11.9 ppm/°C, respectively. Raman spectra, Shannon's additive rule, a classical oscillator model, and far-infrared spectra were employed to study the structure-property relations in detail. All evidence supported the premise that Bi-based vibrations dominate the dielectric permittivity in the microwave region

    Genome-wide association study of peripheral neuropathy with D-drug-containing regimens in AIDS Clinical Trials Group protocol 384.

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    Stavudine (d4T) was, until recently, one of the most widely prescribed antiretroviral drugs worldwide. While there has been a major shift away from d4T use in resource-limited countries, a large number of patients have previously received (or continue to receive) d4T, and many have developed peripheral neuropathy. The identification of genetic predictors of increased risk might suggest novel therapeutic targets for such patients. In AIDS Clinical Trials Group protocol 384, antiretroviral-naïve patients were randomized to d4T/didanosine (ddI)- or zidovudine/lamivudine-containing regimens. Data from d4T/ddI recipients were analyzed for genome-wide associations (approximately 1 million genetic loci) with new onset distal sensory peripheral neuropathy. Analyses involved 254 patients (49 % White, 34 % Black, 17 % Hispanic), comprising 90 peripheral neuropathy cases (32 grade 1, 35 grade 2, 23 grade 3) and 164 controls. After correcting for multiple comparisons, no polymorphism was consistently associated with neuropathy among all patients, among White, Black, and Hispanic patients analyzed separately, both in genome-wide analyses (threshold, P &lt; 5.0 × 10(-8)) and focused on 46 neuropathy-associated genes (threshold, P &lt; 3.5 × 10(-5)). In the latter analyses, the lowest P values were in KIF1A among Whites (rs10199388, P = 8.4 × 10(-4)), in LITAF among Blacks (rs13333308, P = 6.0 × 10(-6)), and in NEFL among Hispanics (rs17763685, P = 5.6 × 10(-6)). Susceptibility to d4T/ddI-associated neuropathy is not explained by a single genetic variant with a marked effect

    Analysis of Fracture Behavior of Thin Polycrystalline Diamond Films

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    The effect of the substrate temperature and CH₄ concentrations on the fracture behavior of thin polycrystalline diamond films was systematically investigated by X-ray diffraction and scanning electron microscopy. The results show that the fracture behavior of thin polycrystalline diamond films synthesized by direct current plasma jet chemical vapor deposition is closely related to the substrate temperature and CH₄ concentrations. A high substrate temperature, due to difference in the thermal expansion coefficients of the substrate and the diamond film, causes thin polycrystalline diamond films to generate high residual stresses, which usually exceed fracture strength of thin diamond film and even that of diamond. The fracture toughness is found to drop with the increasing ratio of CH₄ concentration. In case of high CH₄ concentrations, various defects and impurities, such as cracks, microscopic holes, graphite, and amorphous carbon were observed in the films. Thus, the substrate temperature and CH₄ concentrations should be strictly controlled within an appropriate range.С помощью рентгеновской дифракции и сканирующей электронной микроскопии исследовано влияние температуры подложки и показателя концентрации CH₄ на поведение тонких поликристаллических алмазных пленок при разрушении. Показано, что поведение при разрушении тонких поликристаллических алмазных пленок, синтезированных химическим осаждением покрытия с помощью плазменной струи при постоянном токе, зависит от температуры подложки и показателя концентрации CH₄. Большая температура подложки приводит к возникновению высоких остаточных напряжений в тонких поликристаллических алмазных пленках вследствие различных значений коэффициента теплового расширения подложки и алмазной пленки, которые, как правило, оказываются выше значений сопротивления разрушению тонкой алмазной пленки и алмаза. Обнаружено, что вязкость разрушения уменьшается с увеличением показателя концентрации CH₄. По достижении высоких показателей концентрации CH₄ в тонких пленках образуются такие дефекты и примеси, как трещины, микроскопические отверстия, углерод в форме графита и аморфный углерод. Температуру подложки и показатель концентрации CH₄ необходимо контролировать в надлежащем диапазоне.За допомогою рентгенівської дифракції і скануючої електронної мікроскопії досліджено вплив температури підкладки і показника концентрації CH₄ на поведінку тонких полікристалічних алмазних плівок під час руйнування. Показано, що поведінка при руйнуванні тонких полікристалічних алмазних плівок, синтезованих хімічним осадженням покриття за допомогою плазмового струменя на основі постійного струму, залежить від температури підкладки і показника концентрації CH₄. Велика температура підкладки призводить до виникнення в тонких полікристалічних алмазних плівках високих залишкових напружень внаслідок різних значень коефіцієнта теплового розширення підкладки й алмазної плівки, які, як правило, вищі за значення опору руйнуванню тонкої алмазної плівки й алмаза. Виявлено, що в’язкість руйнування зменшується зі збільшенням показника концентрації CH₄. Після досягнення високих показників концентрації CH₄ у тонких плівках мають місце такі дефекти і домішки, як тріщини, макроскопічні отвори, вуглець у формі графіту і аморфний вуглець. Температуру підкладки і показник концентрації потрібно контролювати в необхідних межах

    Polarization of AGN in UV Spectral Range

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    We present the review of some new problems in cosmology and physics of stars in connection with future launching of WSO. We discuss three problems. UV observations of distant z > 6 quasars allow to obtain information on the soft < 1 KeV X-ray radiation of the accretion disk around a supermassive black hole because of its cosmological redshift. Really the region of X-ray radiation is insufficiently investigated because of high galactic absorption. In a result one will get important information on the reionization zone of the Universe. Astronomers from ESO revealed the effect of alignment of electric vectors of polarized QSOs. One of the probable mechanism of such alignment is the conversion of QSO radiation into low mass pseudoscalar particles (axions) in the extragalactic magnetic field. These boson like particles have been predicted by new SUSY particle physics theory. Since the probability of such conversion is increasing namely in UV spectral range one can expect the strong correlation between UV spectral energy distribution of QSO radiation and polarimetric data in the optical range. In the stellar physics one of the interesting problems is the origin of the X-ray sources with super Eddington luminosities. The results of UV observations of these X-ray sources will allow to find the origin of these sources as accreting intermediate mass black holes.Comment: 6 pages, 3 figure

    The Five Factor Model of personality and evaluation of drug consumption risk

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    The problem of evaluating an individual's risk of drug consumption and misuse is highly important. An online survey methodology was employed to collect data including Big Five personality traits (NEO-FFI-R), impulsivity (BIS-11), sensation seeking (ImpSS), and demographic information. The data set contained information on the consumption of 18 central nervous system psychoactive drugs. Correlation analysis demonstrated the existence of groups of drugs with strongly correlated consumption patterns. Three correlation pleiades were identified, named by the central drug in the pleiade: ecstasy, heroin, and benzodiazepines pleiades. An exhaustive search was performed to select the most effective subset of input features and data mining methods to classify users and non-users for each drug and pleiad. A number of classification methods were employed (decision tree, random forest, kk-nearest neighbors, linear discriminant analysis, Gaussian mixture, probability density function estimation, logistic regression and na{\"i}ve Bayes) and the most effective classifier was selected for each drug. The quality of classification was surprisingly high with sensitivity and specificity (evaluated by leave-one-out cross-validation) being greater than 70\% for almost all classification tasks. The best results with sensitivity and specificity being greater than 75\% were achieved for cannabis, crack, ecstasy, legal highs, LSD, and volatile substance abuse (VSA).Comment: Significantly extended report with 67 pages, 27 tables, 21 figure

    Protecting Quantum Information with Entanglement and Noisy Optical Modes

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    We incorporate active and passive quantum error-correcting techniques to protect a set of optical information modes of a continuous-variable quantum information system. Our method uses ancilla modes, entangled modes, and gauge modes (modes in a mixed state) to help correct errors on a set of information modes. A linear-optical encoding circuit consisting of offline squeezers, passive optical devices, feedforward control, conditional modulation, and homodyne measurements performs the encoding. The result is that we extend the entanglement-assisted operator stabilizer formalism for discrete variables to continuous-variable quantum information processing.Comment: 7 pages, 1 figur

    Supranutritional supplementation of vitamin E influences mitochondrial proteome profile of post-mortem longissimus lumborum from feedlot heifers

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    Supplementation of vitamin E improves beef colour stability by minimizing lipid oxidation-induced myoglobin oxidation. Mitochondria affect myoglobin redox stability, and dietary vitamin E influences mitochondrial functionality in skeletal muscles. Nonetheless, the influence of vitamin E on the mitochondrial proteome of beef skeletal muscles has yet to be  investigated. Therefore, the objective of this study was to examine the effect of dietary vitamin E on mitochondrial proteome of post-mortem beef longissimus lumborum (LL) muscle. Beef LL muscle samples (24 hours post-mortem) were obtained from the carcasses of nine (n = 9) vitamin E-fed (VITE) (1000 IU vitamin E for 89 days) and nine (n = 9) control (CONT) (diet without supplemental vitamin E) heifers. The mitochondrial proteome was analysed using two-dimensional gel electrophoresis and mass spectrometry, and nine differentially abundant spots were identified. All the differentially abundant spots were over-abundant in CONT, and the proteins were electron transport chain enzymes (NADH dehydrogenase iron-sulphur protein 8, NADH dehydrogenase flavoprotein 2, and cytochrome c oxidase subunit 5B), metabolic enzymes (succinate-CoA ligase (ADP-forming) subunit beta; dihydrolipoyllysine-residue succinyltransferase component of 2-oxoglutarate dehydrogenase complex; pyruvate dehydrogenase protein X component), and enzymes involved in ATP regeneration (creatine kinase S-type). The low abundance of these proteins in VITE may decrease mitochondrial activity, resulting in low oxidative activity. These findings suggest that the strong antioxidant activity of vitamin E leads to less expression of mitochondrial oxidative enzymes in beef skeletal muscles.Keywords: Beef colour, lipid oxidation, mitochondrial enzyme
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