Implementing quantum logic gates with GRAPE: principles and practicalities

We briefly describe the use of GRAPE pulses to implement quantum logic gates in NMR quantum computers, and discuss a range of simple extensions to the core technique. We then consider a range of difficulties which can arise in practical implementations of GRAPE sequences, reflecting non-idealities in the experimental systems used.Comment: 15 pages rspublic including 4 figures. This is the original manuscript preprint form which differs slightly from the final accepted version (Phil Trans Roy Soc A in press

pp-regularity of the pp-adic valuation of the Fibonacci sequence

We show that the $p$-adic valuation of the sequence of Fibonacci numbers is a $p$-regular sequence for every prime $p$. For $p \neq 2, 5$, we determine that the rank of this sequence is $\alpha(p) + 1$, where $\alpha(m)$ is the restricted period length of the Fibonacci sequence modulo $m$.Comment: 7 pages; publication versio

Version Control in Online Software Repositories

Software version control repositories provide a uniform and stable interface to manage documents and their version histories. Unfortunately, Open Source systems, for example, CVS, Subversion, and GNU Arch are not well suited to highly collaborative environments and fail to track semantic changes in repositories. We introduce document provenance as our Description Logic framework to track the semantic changes in software repositories and draw interesting results about their historic behaviour using a rule-based inference engine. To support the use of this framework, we have developed our own online collaborative tool, leveraging the fluency of the modern WikiWikiWeb

Version Control in Online Software Repositories

Software version control repositories provide a uniform and stable interface to manage documents and their version histories. Unfortunately, Open Source systems, for example, CVS, Subversion, and GNU Arch are not well suited to highly collaborative environments and fail to track semantic changes in repositories. We introduce document provenance as our Description Logic framework to track the semantic changes in software repositories and draw interesting results about their historic behaviour using a rule-based inference engine. To support the use of this framework, we have developed our own online collaborative tool, leveraging the fluency of the modern WikiWikiWeb

Modality effects in vocabulary acquisition

It is unknown whether modality affects the efficiency with which humans learn novel word forms and their meanings, with previous studies reporting both written and auditory advantages. The current study implements controls whose absence in previous work likely offers explanation for such contradictory findings. In two novel word learning experiments, participants were trained and tested on pseudoword - novel object pairs, with controls on: modality of test, modality of meaning, duration of exposure and transparency of word form. In both experiments word forms were presented in either their written or spoken form, each paired with a pictorial meaning (novel object). Following a 20-minute filler task, participants were tested on their ability to identify the picture-word form pairs on which they were trained. A between subjects design generated four participant groups per experiment 1) written training, written test; 2) written training, spoken test; 3) spoken training, written test; 4) spoken training, spoken test. In Experiment 1 the written stimulus was presented for a time period equal to the duration of the spoken form. Results showed that when the duration of exposure was equal, participants displayed a written training benefit. Given words can be read faster than the time taken for the spoken form to unfold, in Experiment 2 the written form was presented for 300 ms, sufficient time to read the word yet 65% shorter than the duration of the spoken form. No modality effect was observed under these conditions, when exposure to the word form was equivalent. These results demonstrate, at least for proficient readers, that when exposure to the word form is controlled across modalities the efficiency with which word form-meaning associations are learnt does not differ. Our results therefore suggest that, although we typically begin as aural-only word learners, we ultimately converge on developing learning mechanisms that learn equally efficiently from both written and spoken materials

Millipeds from the eastern Dakotas and western Minnesota, USA, with an account of Pseudopolydesmus serratus (Say, 1821) (Polydesmida: Polydesmidae); first published records from six states and the District of Columbia

The diplopod orders Callipodida and Polydesmida, and their respective families Abacionidae and Xystodesmidae, are initially recorded from South Dakota as is Polydesmidae from North Dakota. Other new records of indigenous taxa include Abacion Rafinesque, 1820/A. texense (Loomis, 1937) and Pleuroloma/P. flavipes, both by Rafinesque, 1820, from South Dakota, and Pseudopolydesmus Attems, 1898/P. serratus (Say, 1821) from Alabama, Connecticut, Delaware, New Hampshire, North Dakota, South Carolina, and the District of Columbia. New records of Aniulus garius Chamberlin, 1912, A. (Hakiulus) d. diversifrons (Wood, 1867), and Oriulus venustus (Wood, 1864) (Julida: Parajulidae) are provided for western Minnesota and/or eastern North Dakota. Published records from these states are summarized, and the introduced taxa, Julidae/Cylindroiulus Verhoeff, 1894/C. caeruleocinctus (Wood, 1864) and Paradoxosomatidae/Oxidus Cook, 1911/O. gracilis (C. L. Koch, 1847), are newly recorded from the Dakotas. The distribution of P. serratus, which extends from Maine to South Carolina and the Florida panhandle, west to Texas, and north to Fargo, North Dakota is described and discussed. This distribution exhibits a prominent southeastern lacuna which we hypothesize suggests replacement by younger, more successful species, as postulated for a similar distributional gap in Scytonotus granulatus (Say, 1821)

Upward Influence in Organizations: Test of A Model

A causal model of upward influence in organizations was proposed and tested on a sample of staff nurses and their supervisors in a hospital setting. LISREL results demonstrated that the proposed model fit the data well, and reflected a better fit than several alternative models that were estimated. The contributions and limitations of the present study are discussed, in addition to challenges and directions for future research