Manifold algorithmic errors in quantum computers with static internal imperfections

The inevitable existence of static internal imperfections and residual interactions in some quantum computer architectures result in internal decoherence, dissipation, and destructive unitary shifts of active algorithms. By exact numerical simulations we determine the relative importance and origin of these errors for a Josephson charge qubit quantum computer. In particular we determine that the dynamics of a CNOT gate interacting with its idle neighboring qubits via native residual coupling behaves much like a perturbed kicked top in the exponential decay regime, where fidelity decay is only weakly dependent on perturbation strength. This means that retroactive removal of gate errors (whether unitary or non-unitary) may not be possible, and that effective error correction schemes must operate concurrently with the implementation of subcomponents of the gate

Exact norm-conserving stochastic time-dependent Hartree-Fock

We derive an exact single-body decomposition of the time-dependent Schroedinger equation for N pairwise-interacting fermions. Each fermion obeys a stochastic time-dependent norm-preserving wave equation. As a first test of the method we calculate the low energy spectrum of Helium. An extension of the method to bosons is outlined.Comment: 21 pages, 3 figures, LaTeX fil

Probing Synergy between Two Catalytic Strategies in the Glycoside Hydrolase O-GlcNAcase Using Multiple Linear Free Energy Relationships

Human O-GlcNAcase plays an important role in regulating the post-translational modification of serine and threonine residues with β-O-linked N-acetylglucosamine monosaccharide unit (O-GlcNAc). The mechanism of O-GlcNAcase involves nucleophilic participation of the 2-acetamido group of the substrate to displace a glycosidically linked leaving group. The tolerance of this enzyme for variation in substrate structure has enabled us to characterize O-GlcNAcase transition states using several series of substrates to generate multiple simultaneous free-energy relationships. Patterns revealing changes in mechanism, transition state, and rate-determining step upon concomitant variation of both nucleophilic strength and leaving group abilities are observed. The observed changes in mechanism reflect the roles played by the enzymic general acid and the catalytic nucleophile. Significantly, these results illustrate how the enzyme synergistically harnesses both modes of catalysis; a feature that eludes many small molecule models of catalysis. These studies also suggest the kinetic significance of an oxocarbenium ion intermediate in the O-GlcNAcase-catalyzed hydrolysis of glucosaminides, probing the limits of what may be learned using nonatomistic investigations of enzymic transition-state structure and offering general insights into how the superfamily of retaining glycoside hydrolases act as efficient catalysts

Effect of grafting on iron uptake of farold 40, ohf 333 and ohf 87 pear rootstocks from the soil

WOS:000598218900001The response of cultivars to iron (Fe) deficiency and the effects of cultivars on Fe-nutrition of rootstocks was investigated through Active-Fe content of the leaf. Leaf samples were taken from the mid-sections of the nursery trees and they were subjected to Active-Fe and Total–Fe analyses. There were significant differences in Fe-nutrition of ungrafted rootstocks, but differences were not observed when the rootstocks were grafted pear cultivars cv. ‘Deveci’ and ‘Santa Maria.’ On the other hand, significant differences were observed between the cultivars when they were grafted on different rootstocks. The effect of cultivar on Fe-nutrition of the rootstock was also found to be significant. According to the ungrafted rootstock, cultivars except ‘Deveci’ grafted on Old Home x Farmingdale (OHxF) 333 (OHF 333) decreased the Fe-nutrition of the rootstock. The combination of OHF 333 x ‘Deveci’ was quite different and it significantly improved the Fe-uptake of the rootstock. It should be taken into consideration cultivar-induced and/or rootstock x cultivar combinations-induced differences under chlorosis-induced conditions at the new pear orchard establishment. © 2020 Taylor & Francis Group, LLC

Graft-compatibility of rootpac rootstocks with nectarine and peach cultivars

Interspecific hybrids or clones from different Prunus species can be used as rootstocks for peaches. Recently, the Rootpac rootstocks have been released and begun to be used for peaches. Therefore, grafting aptitude and their compatibility with peach and nectarine cultivars should be examined. The aim of this study is to determine the graft-compatibility performance of different clonal Rootpac rootstocks with peach and nectarine cultivars. Graft unions of peaches and nectarines on Rootpac rootstocks were monitored at the Fruit Research Institute in Eğirdir, Isparta, Turkey. The peach cultivars 'Monroe', 'Royal Glory', 'Q'Henry', 'Vista Rich', 'Cresthaven' and the nectarine cultivar 'Venus' were T-budded on Rootpac-R, Rootpac-90, Rootpac-70, Rootpac-40 and Rootpac-20. The graft samples were evaluated with a microscope at 1, 4 and 12 months after budding. Cambial differentiation occurred after a callus bridge was formed between the two parts of the graft. The graft union and development was observed to be successful. Consequently, no evidence for histological incompatibility was found. In addition, no incompatibility visual symptoms (drying, chlorosis on the leaves, premature death of the trees, marked difference in the growth rate or vigor of scion and stock, over growth at, above or below the graft union, etc.) were observed until the third vegetative season of the budded trees. © 2020 International Society for Horticultural Science. All rights reserved.We would like to thank TAGEM (General Directorate of Agricultural Research and Policies) and Agromillora Seedling Production and Marketing Company for their support for this project

Rootpac anaçlarına aşılı badem, erik ve kayısı çeşitlerinin aşı kaynaşma durumları

The aim of this study was to obtain a basic information about the graft union formation in relation with growth characteristics between ‘Rootpac’ rootstocks and almond, plum and apricot varieties. In this trial, ‘Rootpac-R’, ‘Rootpac-90’, ‘Rootpac-70’, ‘Rootpac-40’, ‘Rootpac-20’ rootstocks and ‘Nonpareil’, ‘Ferragnes’ almond, ‘Aprikoz’, ‘Hacıhaliloğlu’ apricot and ‘Black Diamond’, ‘Papaz’ plum cultivars were used as plant materials. 1, 4 and 12 months after T budding, graft samples were evaluated microscopically and macroscopically. Transverse sections (20-45 µ) were cut by rotary microtome. At transverse sections that taken from 4 and 12 months after grafting were observed forming of callus in all combinations from scion and rootstocks, being broken of necrotic layer as different densities and occurring of cambial differentiations and cambial continuity between scion and rootstock were established. However, tissue development differences were observed in the combinations of ‘Aprikoz’ and ‘Hacıhaliloğlu’ apricots grafted on ‘Rootpac-R’, ‘Black Diamond’ plum grafted on ‘Rootpac-40’, and ‘Black Diamond’ plum, ‘Papaz’ plum, ‘Aprikoz’ and ‘Hacıhaliloğlu’ apricots grafted on ‘Rootpac-20’.Bu çalışma, Rootpac anaçlarının badem, erik ve kayısı çeşitleri ile aşı kaynaşma durumlarını hakkında kısa sürede temel bir bilgi edinebilmek amacı ile yapılmıştır. Bu araştırmada bitki materyali olarak ‘Rootpac-R’, ‘Rootpac-90’, ‘Rootpac-70’, ‘Rootpac-40’, ‘Rootpac-20’ anaçları ve ‘Nonpareil’, ‘Ferragnes’ badem, ‘Aprikoz’, ‘Hacıhaliloğlu’ kayısı ve ‘Black Diamond’ ve ‘Papaz’ erik çeşitleri kullanılmıştır. T göz aşısı yöntemi ile oluşturulan kombinasyonlardan alınan 1, 4 ve 12 ay sonra aşı örnekleri mikroskobik ve makroskopik olarak değerlendirilmiştir. Enine kesitler (20-45 μ) rotary mikrotom ile kesilmiş ve enine kesitlerde aşılamadan 4 ve 12 ay sonra alınan, kalem ve anaçtan elde edilen tüm kombinasyonlarda kallus oluştuğu, farklı yoğunluklardaki nekrotik tabakaların kırıldığı ve kalem ile anaç arasında kambiyal farklılığın ve kambiyal sürekliliğin sağlandığı gözlenmiştir. Bununla birlikte, ‘Rootpac-R’ üzerine aşılanmış ‘Aprikoz’ ve ‘Hacıhalioğlu’ kayısı çeşitlerinin, ‘Rootpac-40’ üzerine aşılanmış ‘Black Diamond’ çeşidinin, ‘Rootpac-20’ üzerine aşılanmış ‘Papaz’ erik, ‘Aprikoz’ ve ‘Hacıhaliloğlu’ kayısı çeşitlerinin oluşturduğu kombinasyonlarda doku gelişiminde farklılıklar gözlenmiştir.We would like to thank to TAGEM (General Directorate of Agricultural Research and Policies) and Agromillora Seedling Production and Marketing Company through their support for this project