Entangling unitary gates on distant qubits with ancilla feedback

By using an ancilla qubit as a mediator, two distant qubits can undergo a non-local entangling unitary operation. This is desirable for when attempting to scale up or distribute quantum computation by combining fixed static local sets of qubits with ballistic mediators. Using a model driven by measurements on the ancilla, it is possible to generate a maximally entangling CZ gate while only having access to a less entangling gate between the pair qubits and the ancilla. However this results in a stochastic process of generating control phase rotation gates where the expected time for success does not correlate with the entangling power of the connection gate. We explore how one can use feedback into the preparation and measurement parameters of the ancilla to speed up the expected time to generate a CZ gate between a pair of separated qubits and to leverage stronger coupling strengths for faster times. Surprisingly, by choosing an appropriate strategy, control of a binary discrete parameter achieves comparable speed up to full continuous control of all degrees of freedom of the ancilla.Comment: 8 pages, 11 figure

A minimum control ancilla driven quantum computation scheme with repeat-until-success style gate generation

Some two qubit interactions are singly sufficient for universal quantum computation but not without the use of an ancilla. Recent schemes for universal quantum computation have focused on hybrid physical systems using ancillae. In them, the application of resources is shifted to the ancilla system. We consider which 2-qubit interactions are universal in ancilla schemes where direct connections between main register qubits are forbidden. By the use of ancilla driven operations and repeat-until-success style random gates, a single fixed symmetric gate can be universal be control of the number of repetitions alone

Effects of a saponin fraction extracted from Trigonella foenum-graecum L. and two commercially available saponins on sex ratio and gonad histology of Nile tilapa fry, Oreochromis niloticus (L.)

Over three million tonnes (t) of tilapia, mostly Nile tilapia (Oreochromis niloticus, L.), are produced annually making it the second most abundantly produced freshwater fish (FAO, 2010). Tilapia are mouthbreeders that often produce stunted populations under pond conditions; one means of prevention is to produce all-male fish with the additional advantage that males usually grow faster than females. All-male populations can be achieved by supplementing feed with androgens such as 17-α-Methyltestosterone (MT) during days 10–25 post-hatch (Pandian and Sheela, 1995). However, MT is considered to be carcinogenic (Velazquez and Alter, 2004), and Hulak et al. (2008) also showed that effluents of systems in which carp were fed diets containing MT caused masculinization of female fish. Furthermore, in aquaculture the application of hormones to fish destined for human consumption is prohibited in the European Union under directive 96/22/EC, article 5, which also prohibits import of animal products produced with hormones. Kwon et al. (2000) showed that Fadrozole, a non-steroidal compound, caused masculinization in tilapia by inhibiting aromatase, which is the enzyme responsible for the conversion of endogenous androgens to estrogens. Steinbronn et al. (2004) were able to show that a dose of 2000 ppm Quillaja saponins (Sigma S-2149) inhibited reproduction of tilapia after dietary application for 32 days to first-feeding fry, suggesting saponins as a possible alternative to MT. These secondary plant compounds consist of either a steroid or triterpenoid basic structure (aglycone or sapogenin) plus one or more sugar side chains (Francis et al., 2002a). In a previous experiment a saponin fraction from the soapbark tree (Quillaja saponaria M.) inhibited aromatase in vitro (Golan et al., 2008). The fenugreek plant (Trigonella foenum-graecum L), widely cultivated in the Middle East and Asia, also has a high saponin content. The experiment was therefore conducted to test whether saponin fractions from Q. saponaria and from T. foenum-graecum were able to influence the sex ratio and gonad histology of Nile tilapia

Model comparison for aftershock sequences following the 2005 Kashmir disaster

In an earlier study (Van Lieshout and Stein, in press) we postulated the existence of two major earthquakes in Kashmir instead of a single one, based upon the pattern of aftershocks. In this note we explore this pattern further by fitting several spatial point pattern models. In particular we discuss the Hawkes and the trigger process models for earthquake aftershock sequences following the Kashmir catastrophe in 2005. The minimum contrast method is used for estimation of the parameters. The study shows that the trigger model fits better than the Hawkes model. The most likely number of main shocks is rounded to 2 generating the almost 200 aftershocks, whereas the Hawkes model would estimate a parent process of approximately 18 parents with on average 10 descendants. We conclude that the spatial pattern of aftershocks can best be understood as being generated by the trigger point process model

On the naming of innovation districts

Name plays a fundamental role in defining and differentiating a company within a category. In this paper we identify how the leaders of 7 innovation districts (22@Barcelona, Ann Arbor Spark, EECi, Porto Digital, Ruta N – Medellín, SK-Skolkovo and TusPark) understand the construction of the names of their innovation districts. We take an inductive approach utilizing two types of data: exploring the innovation district directors' understanding through direct semi-structured interviews and analyzing secondary data consisting of website and brochures. We show how innovation district leaders use more than one classification name for their organization and that these names either tend towards a more strategic or institutional posture. We contribute by extending existing naming theory to include innovation districts, a complex organization composed by actors of the Triple Helix. We also contribute by providing managerial guidance to assist in understanding the importance of the role of their organization's name in long-term positioning

DNA choreography: correlating mobility and organization of DNA across different resolutions from loops to chromosomes

The dynamics of DNA in the cell nucleus plays a role in cellular processes and fates but the interplay of DNA mobility with the hierarchical levels of DNA organization is still underexplored. Here, we made use of DNA replication to directly label genomic DNA in an unbiased genome-wide manner. This was followed by live-cell time-lapse microscopy of the labeled DNA combining imaging at different resolutions levels simultaneously and allowing one to trace DNA motion across organization levels within the same cells. Quantification of the labeled DNA segments at different microscopic resolution levels revealed sizes comparable to the ones reported for DNA loops using 3D super-resolution microscopy, topologically associated domains (TAD) using 3D widefield microscopy, and also entire chromosomes. By employing advanced chromatin tracking and image registration, we discovered that DNA exhibited higher mobility at the individual loop level compared to the TAD level and even less at the chromosome level. Additionally, our findings indicate that chromatin movement, regardless of the resolution, slowed down during the S phase of the cell cycle compared to the G1/G2 phases. Furthermore, we found that a fraction of DNA loops and TADs exhibited directed movement with the majority depicting constrained movement. Our data also indicated spatial mobility differences with DNA loops and TADs at the nuclear periphery and the nuclear interior exhibiting lower velocity and radius of gyration than the intermediate locations. On the basis of these insights, we propose that there is a link between DNA mobility and its organizational structure including spatial distribution, which impacts cellular processes

On the equivalence of strong formulations for capacitated multi-level lot sizing problems with setup times

Several mixed integer programming formulations have been proposed for modeling capacitated multi-level lot sizing problems with setup times. These formulations include the so-called facility location formulation, the shortest route formulation, and the inventory and lot sizing formulation with (l,S) inequalities. In this paper, we demonstrate the equivalence of these formulations when the integrality requirement is relaxed for any subset of binary setup decision variables. This equivalence has significant implications for decomposition-based methods since same optimal solution values are obtained no matter which formulation is used. In particular, we discuss the relax-and-fix method, a decomposition-based heuristic used for the efficient solution of hard lot sizing problems. Computational tests allow us to compare the effectiveness of different formulations using benchmark problems. The choice of formulation directly affects the required computational effort, and our results therefore provide guidelines on choosing an effective formulation during the development of heuristic-based solution procedures

Fit and Tipsy? The Interrelationship between Cardiorespiratory Fitness and Alcohol Consumption and Dependence

Purpose To examine whether higher levels of cardiorespiratory fitness are related to increased alcohol consumption and dependence among a large sample of adults attending a preventive medicine clinic.Methods A cross-sectional study of 38,653 apparently healthy patients who visited the Cooper Clinic (Dallas, TX) for preventive medical examinations (1988–2019) and enrolled in the Cooper Center Longitudinal Study. The primary independent variable was cardiorespiratory fitness, based on a maximal treadmill test, and the dependent variables were alcohol consumption and dependence (self-reported). The relations between fitness category (low, moderate, high) and alcohol consumption (low, moderate, heavy) and suggested alcohol dependence (Cut down, Annoyed, Guilty, Eye opener score ≥2) among women and men were estimated via multivariable regression while adjusting for covariates (e.g., age, birth year cohort, marital status, and body mass index).Results Women within the moderate and high fitness categories had 1.58 (95% confidence interval [CI], 1.32–1.91) and 2.14 (95% CI, 1.77–2.58) greater odds of moderate/heavy alcohol consumption, respectively, in comparison to their low fitness counterparts. Similarly, moderate and high fit men had 1.42 (95% CI, 1.30–1.55) and 1.63 (95% CI, 1.49–1.80) times greater odds of moderate-to-heavy alcohol consumption, respectively, in comparison to the low fitness group. In addition, among men who were heavy drinkers (but not women), higher fitness levels were related to lower rates of suggested alcohol dependence. Specifically, these men had 45.7%, 41.7%, and 34.9% proportions of clinically relevant alcohol problems across low, moderate, and high fitness categories (adjusted P for trend &lt;0.001).Conclusions Higher fitness levels are significantly related to greater alcohol consumption among a large cohort of adult patients. Interventions focusing on increasing fitness (via physical activity promotion) might consider concurrently aiming to reduce alcohol consumption.<br/

A linear programming-based method for job shop scheduling

We present a decomposition heuristic for a large class of job shop scheduling problems. This heuristic utilizes information from the linear programming formulation of the associated optimal timing problem to solve subproblems, can be used for any objective function whose associated optimal timing problem can be expressed as a linear program (LP), and is particularly effective for objectives that include a component that is a function of individual operation completion times. Using the proposed heuristic framework, we address job shop scheduling problems with a variety of objectives where intermediate holding costs need to be explicitly considered. In computational testing, we demonstrate the performance of our proposed solution approach