Fidelity enhancement by logical qubit encoding

We demonstrate coherent control of two logical qubits encoded in a decoherence free subspace (DFS) of four dipolar-coupled protons in an NMR quantum information processor. A pseudo-pure fiducial state is created in the DFS, and a unitary logical qubit entangling operator evolves the system to a logical Bell state. The four-spin molecule is partially aligned by a liquid crystal solvent, which introduces strong dipolar couplings among the spins. Although the system Hamiltonian is never fully specified, we demonstrate high fidelity control over the logical degrees of freedom. In fact, the DFS encoding leads to higher fidelity control than is available in the full four-spin Hilbert space.Comment: 10 pages, 2 figure

Using error correction to determine the noise model

Quantum error correcting codes have been shown to have the ability of making quantum information resilient against noise. Here we show that we can use quantum error correcting codes as diagnostics to characterise noise. The experiment is based on a three-bit quantum error correcting code carried out on a three-qubit nuclear magnetic resonance (NMR) quantum information processor. Utilizing both engineered and natural noise, the degree of correlations present in the noise affecting a two-qubit subsystem was determined. We measured a correlation factor of c=0.5+/-0.2 using the error correction protocol, and c=0.3+/-0.2 using a standard NMR technique based on coherence pathway selection. Although the error correction method demands precise control, the results demonstrate that the required precision is achievable in the liquid-state NMR setting.Comment: 10 pages, 3 figures. Added discussion section, improved figure

Benchmarking quantum control methods on a 12-qubit system

In this letter, we present an experimental benchmark of operational control methods in quantum information processors extended up to 12 qubits. We implement universal control of this large Hilbert space using two complementary approaches and discuss their accuracy and scalability. Despite decoherence, we were able to reach a 12-coherence state (or 12-qubits pseudo-pure cat state), and decode it into an 11 qubit plus one qutrit labeled observable pseudo-pure state using liquid state nuclear magnetic resonance quantum information processors.Comment: 11 pages, 4 figures, to be published in PR

Practice Settings and Dialectical Behavior Therapy Implementation: A mixed method analysis

Background and Significance: Implementation science is the study of transferring innovation into practice. Guided by The Consolidated Framework for Implementation Research (CFIR), this study analyzes Dialectical Behavior Therapy (DBT) utilization in the real world. Such an inquiry informs DBT-uptake in settings, whereby increasing employment of the current gold standard treatment for suicide, non-suicidal self-injury, and behavioral dysregulation. Methods: Seventy-nine intensively trained DBT clinicians completed an online survey that quantified implementation outcomes and practice-setting variables. Practice setting variables were compared to DBT implementation using bivariate analyses. Twenty sequential semi-structured interviews bolstered quantitative findings while exploring the field of inquiry that could not be quantified. Findings and Limitations: Supervision, team cohesion, team communication, and team climate were significantly correlated with DBT implementation and bolstered by qualitative themes. Four other practice-setting variables were related with moderate significance and little qualitative support, and additional hypotheses were generated. Limitations require consideration of the current research as exploratory. Conclusions: The four variables with the clearest connection to DBT implementation can be characterized as interpersonal variables within practice settings. These findings contribute to the identification of key drivers of successful DBT implementation within settings. Future researchers are advised to develop and test implementation strategies incorporating these findings. Practitioners should be mindful of these variables when implementing DBT

Ontogeny and intervals of development in five reef-associated species of blenny from the northern Gulf of Mexico (Teleostei: Blenniidae)

I examined patterns and timing of ontogeny and relative growth in five species of blenny (Teleostei: Blenniidae) from the northern Gulf of Mexico by assigning a suite of discrete character state scores to ontogenetic events (10 external traits; 218 total specimens). This is the first study to evaluate developmental patterns in reef-associated fishes relative to the timing of metamorphosis and settlement by applying scaling techniques and statistical methods to quantify, differentiate, and select criteria for defining intervals of development across taxa. Blennies settle at a common state of ontogeny and share a common pattern of body and fin/cirrus growth. Three \u27natural\u27 intervals of development (labeled \u27larvae\u27, \u27metamorphs\u27, and \u27settlers\u27) were consistently identified based on scoring and summing character states, and cluster analysis. Shape differences separate larvae from metamorphs, but not metamorphs from recent settlers. The common growth pattern consists of a general deepening of the head and abdomen, a narrowing of the interorbital region, and elongation of the pectoral and pelvic fins. These changes during metamorphosis produce the common shape and basic adult body form at settlement. Differences in shape show little relationship to phylogenetic distance. Estuarine blennies settle at a smaller size but similar state of ontogeny as coastal/shelf species, which suggests the timing, rate, and state of ontogeny at important periods of ecological transition, may influence survival. The smaller size at settlement in estuarine blennies is consistent with natural selection emphasizing rapid ontogeny in species or areas where competition for available habitat or resources is great. Differences in fin and body pigmentation patterns and in the number of teeth between estuarine and coastal/shelf blennies suggest that development reflects adaptive convergence to similar ecological niches and habitats, rather than revealing any evolutionary relationship. In blennies, ontogeny progresses gradually and continuously rather than in a stepwise fashion, as postulated by saltatory theory. Differential growth rates of individual body parts provide a similar conclusion. Variability in the timing and magnitude of ontogeny make recognizing proposed thresholds between \u27steps\u27 difficult, if not impossible. Blennies are not juveniles at settlement as commonly accepted for many other demersal and reef-associated species

Draft genome sequence of the caffeine-degrading methylotroph \u3cem\u3eMethylorubrum populi\u3c/em\u3e Pinkel

A pink-pigmented facultative methylotroph, Methylorubrum populi Pinkel, was isolated from compost by selective enrichment with caffeine (3,5,7-trimethylxanthine) as the sole carbon, nitrogen, and energy source. We report here its high-quality draft genome sequence, assembled in 35 contigs totaling 5,630,907 bp. We identified 5,681 protein-coding sequences, including those putatively involved in caffeine degradation. ABSTRACT A pink-pigmented facultative methylotroph, Methylorubrum populi Pinkel, was isolated from compost by selective enrichment with caffeine (3,5,7-trimethylxanthine) as the sole carbon, nitrogen, and energy source. We report here its high-quality draft genome sequence, assembled in 35 contigs totaling 5,630,907 bp. We identified 5,681 protein-coding sequences, including those putatively involved in caffeine degradation

Robust circadian clocks from coupled protein modification and transcription-translation cycles

The cyanobacterium Synechococcus elongatus uses both a protein phosphorylation cycle and a transcription-translation cycle to generate circadian rhythms that are highly robust against biochemical noise. We use stochastic simulations to analyze how these cycles interact to generate stable rhythms in growing, dividing cells. We find that a protein phosphorylation cycle by itself is robust when protein turnover is low. For high decay or dilution rates (and co mpensating synthesis rate), however, the phosphorylation-based oscillator loses its integrity. Circadian rhythms thus cannot be generated with a phosphorylation cycle alone when the growth rate, and consequently the rate of protein dilution, is high enough; in practice, a purely post-translational clock ceases to function well when the cell doubling time drops below the 24 hour clock period. At higher growth rates, a transcription-translation cycle becomes essential for generating robust circadian rhythms. Interestingly, while a transcription-translation cycle is necessary to sustain a phosphorylation cycle at high growth rates, a phosphorylation cycle can dramatically enhance the robustness of a transcription-translation cycle at lower protein decay or dilution rates. Our analysis thus predicts that both cycles are required to generate robust circadian rhythms over the full range of growth conditions.Comment: main text: 7 pages including 5 figures, supplementary information: 13 pages including 9 figure