Effects of Supplementation of a Pre-workout on Power Maintenance in Lower Body and Upper Body Tasks in Women.

Currently there is a lack of research into how women respond to pre-workout supplementation. The effects of supplements on exercise performance in women, specifically to power, must be performed. This study investigated the effects of supplementation on power production and maintenance during a high-intensity cycle ergometry sprint performance, vertical jump performance, and bench press performance in women. It also investigated the effects of supplementation on power production and the maintenance of upper and lower body tasks in women. A total of 23 females (22.9 ± 3.6 years, 175.6 ± 6.5 cm, 86.9 ± 15.1 kg, 19.1 ± 8.4 body fat percentage (BF%) (mean ± std. dev.)) were familiarized with the testing protocol and maximal bench press performances were attained (49.5 ± 15.4 kg). Utilizing a double-blind crossover design, subjects completed three trials of: Five countermovement vertical jumps, a high-intensity cycle sprint protocol, which consisted of 10 maximal, five second cycle ergometer sprints. Subjects performed a velocity bench press test, utilizing 80% of their predetermined one repetition maximum (1RM) for 10 sets of three repetitions for maximal speed. For 20 min prior to each trial, the subjects ingested, in a randomized order, a pre-workout supplement (Supp), placebo+150 mg caffeine (Caff), or a placebo (PL). Peak power (PP), mean power (MP), and minimum power (MNP) were recorded for each sprint. Maximal velocity from each set was also recorded. Bike sprint and bench press data were normalized to the placebo trial for analysis. Blood lactate (bLa-) was measured immediately prior to each testing session, within 2 min of the completion of the last cycle sprint and following the bench press test. Bike sprint and bench press testing showed no significant differences through the testing sessions, but did significantly decline over test battery (p < 0.05). Vertical jump performance and lactate levels were not significantly different. Supplementation with a pre-workout supplement or placebo with caffeine 20 min prior to participation showed no positive benefits to performance in female participants.

Optimizing the Frequency of Quantum Error Correction.

A common assumption is that one applies a fault-tolerant quantum error correction (FTQEC) after every gate during quantum computing. However, it is known that this is not always optimal, since the FTQEC procedure itself can introduce errors. Here we vary the number of logical gates between FTQEC operations given that a failure of a postselection condition may cause the FTQEC to be skipped. We derive an expression for the logical error rate as a function of the error-correction frequency and find the optimal frequency for the application of the FTQEC. Furthermore, we show that this is relatively insensitive to the postselection failure probability for a large range of such probabilities. We provide an example of the application of the analytic expression to the ⟦7,1,3⟧ Steane code and data derived from a Monte Carlo simulation.

Minimal noise subsystems.

A system subjected to noise contains a decoherence-free subspace or subsystem (DFS) only if the noise possesses an exact symmetry. Here we consider noise models in which a perturbation breaks a symmetry of the noise, so that if S is a DFS under a given noise process it is no longer so under the new perturbed noise process. We ask whether there is a subspace or subsystem that is more robust to the perturbed noise than S. To answer this question we develop a numerical method that allows us to search for subspaces or subsystems that are maximally robust to arbitrary noise processes. We apply this method to a number of examples, and find that a subsystem that is a DFS is often not the subsystem that experiences minimal noise when the symmetry of the noise is broken by a perturbation. We discuss which classes of noise have this property.

Nonperturbative leakage elimination operators and control of a three-level system.

Dynamical decoupling operations have been shown to reduce errors in quantum information processing. Leakage from an encoded subspace to the rest of the system space is a particularly serious problem for which leakage elimination operators (LEOs) were introduced. Here we provide an analysis of nonideal pulses, rather than the well-understood idealization or bang-bang controls. Under realistic conditions, we show that these controls will provide the same protection from errors as idealized controls. Our work indicates that the effectiveness of LEOs depends on the integral of the pulse sequence in the time domain, which has been missing because of the idealization of pulse sequences. Our results are applied to a three-level system for the nitrogen-vacancy centers under an external magnetic field and are illustrated by the fidelity dynamics of LEO sequences, ranging from regular rectangular pulses, random pulses, and even disordered (noisy) pulses.

The relationship between the living arrangements of university students and their identity development.

One of the developmental challenges facing the emerging adult is to live independently of his/her family of origin. Research has shown that the living arrangements of late adolescents/young adults also affect aspects of their personal development. This study examined the relationship between university students' living arrangements, their identity development status, the degree of life difficulties experienced, and the manner in which they coped with their difficulties. In general, it was found that those who did not reside in their parents' home had greater levels of problems but also used more direct, problem-focused coping strategies than did those who resided at home. Individuals residing away from their parents were also more likely to have established an adult identity, whereas those who resided with their parents were more likely to be still in the process of developing an adult identity.

Comprehensive encoding and decoupling solution to problems of decoherence and design in solid-state quantum computing.

Proposals for scalable quantum computing devices suffer not only from decoherence due to the interaction with their environment, but also from severe engineering constraints. Here we introduce a practical solution to these major concerns, addressing solid-state proposals in particular. Decoherence is first reduced by encoding a logical qubit into two qubits, then completely eliminated by an efficient set of decoupling pulse sequences. The same encoding removes the need for single-qubit operations, which pose a difficult design constraint. We further show how the dominant decoherence processes can be identified empirically, in order to optimize the decoupling pulses.

Differences between students' estimated and attained grades in a first-year introductory psychology course as a function of identity development.

Two hundred sixty-eight first-year university students were surveyed about the state of their identity development and their perceptions regarding chances for academic success in an introductory psychology course. In general, it was found that students who had an adult identity had a more accurate assessment of their chances for success in the course and also used more efficient study strategies. Students who had not completely formed an adult identity, however, were more inaccurate in estimates of their final grades and also seemed to use less productive study strategies. It was concluded that those who have formulated an adult identity might have also developed a more complete understanding of both themselves and their situation. Implications of the findings for further research regarding the effects of identity development on university life, as well as the implications for academic intervention programs, are discussed.

Patterns of memory loss in three elderly samples.

Three groups of people ranging in age from 64 to 88 years performed tasks of word generation, paired-associate recall, and free and cued recall. The groups differed in socioeconomic status, verbal intelligence, and apparent levels of daily activity. A fourth group, consisting of young undergraduates, was also tested. Results showed that whereas there were age-related differences in some tests, these age differences were strongly modulated by characteristics of the participants and characteristics of the tasks. The findings are discussed in a contextualist framework.