43,186 research outputs found
Distributed implementation of standard oracle operators
The standard oracle operator corresponding to a function f is a unitary
operator that computes this function coherently, i.e. it maintains
superpositions. This operator acts on a bipartite system, where the subsystems
are the input and output registers. In distributed quantum computation, these
subsystems may be spatially separated, in which case we will be interested in
its classical and entangling capacities. For an arbitrary function f, we show
that the unidirectional classical and entangling capacities of this operator
are log_{2}(n_{f}) bits/ebits, where n_{f} is the number of different values
this function can take. An optimal procedure for bidirectional classical
communication with a standard oracle operator corresponding to a permutation on
Z_{M} is given. The bidirectional classical capacity of such an operator is
found to be 2log_{2}(M) bits. The proofs of these capacities are facilitated by
an optimal distributed protocol for the implementation of an arbitrary standard
oracle operator.Comment: 4.4 pages, Revtex 4. Submitted to Physical Review Letter
The importance of psychological well-being in organisational settings: moving beyond the pleasure principle
In contrast to the emphasis on affective states as components of Subjective Well-Being (SWB), the Psychological Well-Being (PWB) approach considers the role of personal resources, such as mastery and efficacy beliefs, a sense of autonomy, positive relatedness with others, and self acceptance. This study of 679 high-school teachers was based on the Organisational Health Research Framework and compared the contribution of PWB, personality and organisational climate to the prediction of SWB and
organisational well-being. PWB was identified as a significant predictor of SWB even after controlling for
demographic characteristics, organisational climate and personality variables with 46% of the variance in PA and 47% of the variance in NA explained. In addition, PWB contributed uniquely to the prediction of school morale and school distress with the overall set of predictors accounting for 69% of the variance in school morale and 66% of the variance in school distress. Individual interventions which promote PWB components would appear to be a most important avenue by which to improve employee SWB, while organisational interventions that focus on improving the organisational climate should have greater impact on organisational well-bein
Understanding the differential benefits of training for the unemployed
[Abstract]: This study examined the connection between background variables (such as length of unemployment and number of previous training courses), contextual variables (perceptions of training climate), dispositional variables (positive affect and negative affect), and psychological outcomes for unemployed trainees who attended either a five week occupational skills training program (control group) or the same five week program with an additional two day intervention before the start of the program (treatment group). The trainees in both the treatment and control conditions were found to reduce their levels of psychological distress over the course of a five-week training program. Trainees in the treatment condition who started with the lowest levels of general self-efficacy and the highest levels of psychological distress showed the greatest improvements at time 2 (T2). The measures of length of unemployment, number of previous training courses, and the perceptions of the training climate (with one exception) did not account for any unique variance in either of the well-being measures at time 3 (T3). Positive and negative affect (PA and NA respectively) accounted for 30% of the variance in initial levels of general self-efficacy and 43% of the variance in initial levels of psychological distress. However, PA and NA measured at T1 did not account for any unique variance in the T3 levels of general self-efficacy and psychological distress, after the initial levels of each of the variables were controlled. It was concluded that components of dispositional affect are the main influence on how individuals perceive stimuli in the environment and subsequently regulate their emotional response
The influence of acute variable resistance loading on subsequent free-weight maximal squat performance
Elastic bands attached to a loaded barbell during a squat exercise create a variable resistance (VR), thus changing the mechanical loading and stress placed through the musculoskeletal system. Preconditioning the neuromuscular system using near-maximal or maximal voluntary contractions (MVC) can induce a phenomenon known as post-activation potentiation (PAP) to enhance performance to ‘supramaximal’ levels. However, the potentiating effects of VR on subsequent free-weight resistance (FWR) squat performance have not been examined. Thus, the aim of the present study was to examine the influence of VR exercise using elastic bands on subsequent FWR squat performance. Sixteen recreationally active men (age = 26.0 ± 7.8 yr, height = 1.7 ± 0.2 m, mass 82.6 ± 12.7 kg) experienced in squatting (>3yr) volunteered for the study after giving written informed consent; ethical approval was granted from the University of Northampton. Subjects’ 1-RM were determined then on two subsequent days either a 3-RM FWR (control) or a 3-RM VR (experimental) squat exercise was performed at 85% 1-RM (35% of the load generated from band tension in the VR condition). Five minutes later, motion analysis recorded knee joint kinematics during a subsequent FWR 1-RM squat, with vastus medialis, vastus lateralis, rectus femoris and semitendinosus electromyograms (EMG) simultaneously recorded. Paired t-tests were used to determine significance, accepted at p0.05) or EMG amplitude (5.9%; p>0.05) occurred. No subjects increased 1-RM in the FWR condition, however 13 of 16 (81%) increased 1-RM by ~10% following VR. Preconditioning the neuromuscular system using VR significantly increased 1-RM without changes in knee extensor muscle activity or knee flexion angle, however eccentric and concentric velocities were reduced. Thus, VR can potentiate the neuromuscular system to enhance subsequent maximal lifting performance. The lack of change in EMG suggests that changes in muscle activity were small or non-existent, which may be explained by force-velocity effects (slower movement = larger forces). Alternatively a greater activation of hip musculature (not measured in the present study) may allow a greater total lower limb force to be developed. Regardless, as 1-RM increased greater lower-limb loading occurred, thus VR potentiated the neuromuscular system and could enhance training stimuli
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Number of Pages: 6Integrative BiologyGeological Science
Personal effectiveness training for unemployed people: where to now?
Unemployment remains a major social problem in Australia. Successive governments have attempted to address the problem, in part, by funding occupational skills based training programs for the unemployed. This paper reviews the general area of occupational skills/personal effectiveness training for unemployed people, and reports on outcomes for individuals attending 'typical' courses in Australia. Also reported, are outcomes for unemployed people who attended specially devised training, based on the cognitive behavioural (e.g., Beck, 1976) and learned optimism (Seligman, 1990) intervention approaches, that was aimed at improving well-being, confidence and coping abilities.
Variables assessed include individual well-being (e.g., psychological distress), confidence (e.g., self-efficacy), attitude-to-work (e.g., work-commitment); training climate; and labour market outcomes such as return-to-work. More positive outcomes were identified for unemployed people attending the specially devised programs. The authors argue that training targeted at unemployed people must be based on sound theoretical principles to produce measurable long-term benefits. Future applications of personal development programs are discussed in relation to occupational skills based training and as stand-alone
programs
The influence of 6 weeks of maximal eccentric plantarflexor training on muscle-tendon mechanics
Resistance training can influence muscle-tendon properties including strength, flexibility, stretch tolerance and muscle-tendon stiffness; however the specific influence of eccentric-only training is unknown. Therefore, the aims of the present study were to examine the effects of a 6-week maximal eccentric resistance training programme on isometric plantarflexor moment (MVC), dorsiflexion range of motion (ROM), stretch tolerance (peak passive moment), muscle and tendon stiffness and running economy. Thirteen recreationally active men (age = 20.0 ± 0.9 yr, mass = 75.9 ± 8.5 kg, height = 1.8 ± 0.1 m) volunteered for the study after giving written informed consent; ethical approval was granted from the University of Northampton. Training was performed twice weekly for six weeks and consisted of 5 sets of 12 repetitions of 3-s maximal eccentric contractions at 10°•s-1 from 20° plantarflexion to 10° dorsiflexion. Maximal isometric plantarflexor moment, dorsiflexion ROM, stretch tolerance, and muscle, tendon and muscle-tendon unit (MTU) stiffness were measured using isokinetic dynamometry, real-time ultrasound and 3D motion analyses before and after the training. Running economy (VO2) was determined at a running speed equating to 70%VO2max using online gas analysis. Repeated measures t-tests were used to determine significant differences between pre- and post-training data, significance accepted at p0.05). Analysis of ultrasound data revealed a significant decrease in muscle stiffness (20.6%; p0.05). While the training-induced increase in plantarflexor strength was expected, the substantial increases in ROM, stretch tolerance and tendon stiffness, and the reduction in passive muscle stiffness, were important and novel findings. Interestingly, when measured during passive stretch, MTU stiffness remained unchanged while tendon stiffness increased and muscle stiffness decreased. These disparate findings have clear implications for testing methodologies, and indicate that imaging techniques must be utilised in order to examine the effects of interventions on specific tissues. As the training clearly enhanced the capacity of the muscle to tolerate both tissue loading and deformation, which are commonly associated with muscle strain injury, these data have clear implications for both muscular performance and injury risk
Alternative splicing of human prostaglandin G/H synthase mRNA and evidence of differential regulation of the resulting transcripts by transforming growth factor beta 1, interleukin 1 beta, and tumor necrosis factor alpha.
Prostaglandin G/H synthase (PGG/HS) is the rate-limiting enzyme in the conversion of arachidonic acid to prostaglandins and thromboxanes. We screened a human lung fibroblast cDNA library with an ovine PGG/HS cDNA and isolated a 2.3-kilobase clone (HCO-T9). Sequence analysis of this clone showed that (a) it contained the entire translated region of PGG/HS and (b) it displayed an in-frame splicing of the last 111 base pairs encoded by exon 9, which resulted in the elimination of the N-glycosylation site at residue 409. Polymerase chain reaction amplification with specific oligonucleotides of reverse-transcribed mRNA from diverse human tissues and cultured cells yielded 400- and 300-base pair fragments that corresponded, respectively, to the intact and spliced transcripts. The expression of these two transcripts in cultured human lung fibroblasts was differentially regulated by serum, transforming growth factor beta 1, interleukin 1 beta, tumor necrosis factor alpha, and phorbol 12-myristate 13-acetate, as each of these conditions stimulated preferentially the expression of the unspliced transcripts. The elimination of one of the four N-glycosylation sites by the alternative splicing of exon 9 and the differential regulation of this process by relevant cytokines and growth factors may represent a mechanism for the regulation of PGG/HS enzymatic activity under physiological or pathological conditions
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