Discrete phase-space structure of nn-qubit mutually unbiased bases

We work out the phase-space structure for a system of $n$ qubits. We replace the field of real numbers that label the axes of the continuous phase space by the finite field \Gal{2^n} and investigate the geometrical structures compatible with the notion of unbiasedness. These consist of bundles of discrete curves intersecting only at the origin and satisfying certain additional properties. We provide a simple classification of such curves and study in detail the four- and eight-dimensional cases, analyzing also the effect of local transformations. In this way, we provide a comprehensive phase-space approach to the construction of mutually unbiased bases for $n$ qubits.Comment: Title changed. Improved version. Accepted for publication in Annals of Physic

Unpolarized states and hidden polarization

We capitalize on a multipolar expansion of the polarisation density matrix, in which multipoles appear as successive moments of the Stokes variables. When all the multipoles up to a given order $K$ vanish, we can properly say that the state is $K$th-order unpolarized, as it lacks of polarization information to that order. First-order unpolarized states coincide with the corresponding classical ones, whereas unpolarized to any order tally with the quantum notion of fully invariant states. In between these two extreme cases, there is a rich variety of situations that are explored here. The existence of \textit{hidden} polarisation emerges in a natural way in this context.Comment: 7 pages, 3 eps-color figures. Submitted to PRA. Comments welcome

Interactive Statistical Computing For Undergraduate Liberal Arts Education

St. Olaf College at Northfield, Minnesota, has an Interactive Statistical Analysis System for classroom research usage. SODAS (St. Olaf Data Analysis System) operates on a Minicomputer Time Sharing System (DEC PDP / 1140 has 15 terminals, 64K of core, and 3 disks). SODAS is used extensively by students for study of statistics, course projects, and research. In addition, it is used for faculty research . This system has increased student interest by involving them in realistic problems. In addition, student sophistication in problem solving has increased. The paper discusses the system design, the philosophy of interactive computing, and the pedagogical applications in an undergraduate curriculum

The relationship between mental toughness and cognitive control: evidence from the item-method directed forgetting task

Previous research by the authors found that mental toughness, as measured by the Mental Toughness Questionnaire 48 (MTQ48; Clough, P.J., Earle, K., & Sewell, D. [2002]. Mental toughness: the concept and its measurement. In I. Cockerill (Ed.), Solutions in sport psychology [pp. 32–43]. London: Thomson Publishing), was significantly associated with performance on the list-method directed forgetting task. The current study extends this finding to the item-method directed forgetting task in which the instruction to Remember or Forget is given after each item in the study list. A significant positive association was found between the correct recognition of Remember words and the emotional control subscale of the MTQ48. No significant associations were observed with other measures of mental toughness or personality. The findings are discussed in terms of the relationship between mental toughness and cognitive control

Direct measurements of DOCO isomers in the kinetics of OD+CO

Quantitative and mechanistically-detailed kinetics of the reaction of hydroxyl radical (OH) with carbon monoxide (CO) have been a longstanding goal of contemporary chemical kinetics. This fundamental prototype reaction plays an important role in atmospheric and combustion chemistry, motivating studies for accurate determination of the reaction rate coefficient and its pressure and temperature dependence at thermal reaction conditions. This intricate dependence can be traced directly to details of the underlying dynamics (formation, isomerization, and dissociation) involving the reactive intermediates cis- and trans-HOCO, which can only be observed transiently. Using time-resolved frequency comb spectroscopy, comprehensive mechanistic elucidation of the kinetics of the isotopic analogue deuteroxyl radical (OD) with CO has been realized. By monitoring the concentrations of reactants, intermediates, and products in real-time, the branching and isomerization kinetics and absolute yields of all species in the OD+CO reaction are quantified as a function of pressure and collision partner.Comment: 19 pages, 4 figure

Mechanism of Disease:Recessive ADAMTSL4 Mutations and Craniosynostosis with Ectopia Lentis

Craniosynostosis, the premature fusion of the calvarial bones, has numerous etiologies. Among them, several involve mutations in genes related to the TGFb signaling pathway, a critical molecular mediator of human development. These TGFb pathway-associated craniosynostosis syndromes include Loeys-Dietz syndrome (LDS) and Shprintzen-Goldberg syndrome (SGS). LDS and SGS have many similarities common to fibrillinopathies, specifically Marfan syndrome (MFS), which is caused by mutations in FBN1. Historically discriminating features of MFS from LDS and SGS are (1) the presence of ectopia lentis (the subluxation/dislocation of the ocular lens) and (2) the absence of craniosynostosis. Curiously, several instances of a seemingly novel syndrome involving only craniosynostosis and ectopia lentis have recently been reported to be caused by recessive mutations in ADAMTSL4, a poorly characterized gene as of yet. Here, we report on two new cases of craniosynostosis with ectopia lentis, each harboring recessive mutations in ADAMTSL4. We also discuss a proposed mechanism for the relationship between ADAMTSL4, FBN1, and TGFb pathway-related syndromes.</p

Trinity University\u27s Summer Bridge Program: Navigating the Changing Demographics in Higher Education

Our article is divided into five sections. First, our study explores the demographic, economic, and cultural changes influencing higher education. We also explain the tangible and intangible benefits of a college education for first-generation, underrepresented students (FGUS). Second, we provide a brief discussion of the history of Trinity University and our Summer Bridge program. Third, our study describes our Summer Bridge program. Fourth, the data we collected examines how our Summer Bridge students’ grades and retention rates compare to our other first-year students. And, fifth, our article concludes with a discussion of future directions for our Summer Bridge program and how it may apply to other higher educational institutions. In particular, we offer recommendations for other student affairs professionals who also will be experiencing an increase in first-generation, underrepresented students

Short-term order and item retention

This paper evaluates two hypotheses: (a) that transposition errors made in the recall of letter strings occur as a by-product of acoustic confusion errors and do not represent the loss of order information, and (b) that order and item information are independently retained in short-term memory. An experiment was conducted in which four-consonant strings containing exactly zero or two acoustically confusable items were recalled in order after retention intervals of 3, 8, or 18 intervening digits, all characters being successively presented at a rate of 400 msec per item and read aloud by the subject. An analysis of errors in relation to intra- and extrastimulus sources of acoustic confusion, retention interval, and serial position produced results that refute hypothesis (a) and support hypothesis (b). The implications of the present results for an adequate theory of the short-term retention of ordered strings are indicated.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/22414/1/0000864.pd

Implied Filtering Densities on Volatility's Hidden State

We formulate and analyze an inverse problem using derivatives prices to obtain an implied filtering density on volatility's hidden state. Stochastic volatility is the unobserved state in a hidden Markov model (HMM) and can be tracked using Bayesian filtering. However, derivative data can be considered as conditional expectations that are already observed in the market, and which can be used as input to an inverse problem whose solution is an implied conditional density on volatility. Our analysis relies on a specification of the martingale change of measure, which we refer to as \textit{separability}. This specification has a multiplicative component that behaves like a risk premium on volatility uncertainty in the market. When applied to SPX options data, the estimated model and implied densities produce variance-swap rates that are consistent with the VIX volatility index. The implied densities are relatively stable over time and pick up some of the monthly effects that occur due to the options' expiration, indicating that the volatility-uncertainty premium could experience cyclic effects due to the maturity date of the options

Adolescents, Adults and Rewards: Comparing Motivational Neurocircuitry Recruitment Using fMRI

Background: Adolescent risk-taking, including behaviors resulting in injury or death, has been attributed in part to maturational differences in mesolimbic incentive-motivational neurocircuitry, including ostensible oversensitivity of the nucleus accumbens (NAcc) to rewards. Methodology/Principal Findings: To test whether adolescents showed increased NAcc activation by cues for rewards, or by delivery of rewards, we scanned 24 adolescents (age 12–17) and 24 adults age (22–42) with functional magnetic resonance imaging while they performed a monetary incentive delay (MID) task. The MID task was configured to temporally disentangle potential reward or potential loss anticipation-related brain signal from reward or loss notification-related signal. Subjects saw cues signaling opportunities to win or avoid losing $0,$.50, or $5 for responding quickly to a subsequent target. Subjects then viewed feedback of their trial success after a variable interval from cue presentation of between 6 to17 s. Adolescents showed reduced NAcc recruitment by reward-predictive cues compared to adult controls in a linear contrast with non-incentive cues, and in a volume-of-interest analysis of signal change in the NAcc. In contrast, adolescents showed little difference in striatal and frontocortical responsiveness to reward deliveries compared to adults. Conclusions/Significance: In light of divergent developmental difference findings between neuroimaging incentive paradigms (as well as at different stages within the same task), these data suggest that maturational differences i