73 research outputs found
The ‘Blueprint’ framework for career management skills: a critical exploration
This article examines the Blueprint framework for career management skills as it has been revealed across sequential implementations in the USA, Canada and Australia. It is argued that despite its lack of an empirical basis, the framework forms a useful and innovative means through which career theory, practice and policy can be connected. The framework comprises both core elements (learning areas, learning model and levels) and contextual elements (resources, community of practice, service delivery approach and policy connection). Each of these elements is explored
Theory of Fast Quantum Control of Exciton Dynamics in Semiconductor Quantum Dots
Optical techniques for the quantum control of the dynamics of multiexciton
states in a semiconductor quantum dot are explored in theory. Composite
bichromatic phase-locked pulses are shown to reduce the time of elementary
quantum operations on excitons and biexcitons by an order of magnitude or more.
Analytic and numerical methods of designing the pulse sequences are
investigated. Fidelity of the operation is used to gauge its quality. A
modified Quantum Fourier Transform algorithm is constructed with only Rabi
rotations and is shown to reduce the number of operations. Application of the
designed pulses to the algorithm is tested by a numerical simulation.Comment: 11 pages,5 figure
Coherent control using adaptive learning algorithms
We have constructed an automated learning apparatus to control quantum
systems. By directing intense shaped ultrafast laser pulses into a variety of
samples and using a measurement of the system as a feedback signal, we are able
to reshape the laser pulses to direct the system into a desired state. The
feedback signal is the input to an adaptive learning algorithm. This algorithm
programs a computer-controlled, acousto-optic modulator pulse shaper. The
learning algorithm generates new shaped laser pulses based on the success of
previous pulses in achieving a predetermined goal.Comment: 19 pages (including 14 figures), REVTeX 3.1, updated conten
Quantitative profiling of the full APOBEC3 mRNA repertoire in lymphocytes and tissues: implications for HIV-1 restriction
The human APOBEC3 proteins are DNA cytidine deaminases that impede the replication of many different transposons and viruses. The genes that encode APOBEC3A, APOBEC3B, APOBEC3C, APOBEC3D, APOBEC3F, APOBEC3G and APOBEC3H were generated through relatively recent recombination events. The resulting high degree of inter-relatedness has complicated the development of specific quantitative PCR assays for these genes despite considerable interest in understanding their expression profiles. Here, we describe a set of quantitative PCR assays that specifically measures the mRNA levels of each APOBEC3 gene. The specificity and sensitivity of each assay was validated using a full matrix of APOBEC3 cDNA templates. The assays were used to quantify the APOBEC3 repertoire in multiple human T-cell lines, bulk leukocytes and leukocyte subsets, and 20 different human tissues. The data demonstrate that multiple APOBEC3 genes are expressed constitutively in most types of cells and tissues, and that distinct APOBEC3 genes are induced upon T-cell activation and interferon treatment. These data help define the APOBEC3 repertoire relevant to HIV-1 restriction in T cells, and they suggest a general model in which multiple APOBEC3 proteins function together to provide a constitutive barrier to foreign genetic elements, which can be fortified by transcriptional induction
Identification of competing ultrafast all-optical switching mechanisms in Si woodpile photonic crystals
We present a systematic study of ultrafast all-optical switching of Si
photonic band gap woodpile crystals using broadband tunable nondegenerate
pump-probe spectroscopy. At pump-probe coincidence, we investigate the behavior
the differential reflectivity at the blue edge of the stopband for a wide range
of pump- and probe frequencies. Both dispersive and absorptive features are
observed from the probe spectra at coincidence. As the pump frequency is tuned
through half the electronic bandgap of Si, the magnitude of both these features
increases. For the first time we unambiguously identify this dispersive effect
with the electronic Kerr effect in photonic crystals, and attribute the the
absorptive features to nondegenerate two photon absorption. The dispersive and
absorptive nonlinear coefficients are extracted, and are found to agree well
with literature. Finally, we propose a nondegenerate figure of merit (NFOM),
which defines the quality of switching for all nondegenerate optical switching
processes.Comment: Accepted by JOSA
Spintronics: Fundamentals and applications
Spintronics, or spin electronics, involves the study of active control and
manipulation of spin degrees of freedom in solid-state systems. This article
reviews the current status of this subject, including both recent advances and
well-established results. The primary focus is on the basic physical principles
underlying the generation of carrier spin polarization, spin dynamics, and
spin-polarized transport in semiconductors and metals. Spin transport differs
from charge transport in that spin is a nonconserved quantity in solids due to
spin-orbit and hyperfine coupling. The authors discuss in detail spin
decoherence mechanisms in metals and semiconductors. Various theories of spin
injection and spin-polarized transport are applied to hybrid structures
relevant to spin-based devices and fundamental studies of materials properties.
Experimental work is reviewed with the emphasis on projected applications, in
which external electric and magnetic fields and illumination by light will be
used to control spin and charge dynamics to create new functionalities not
feasible or ineffective with conventional electronics.Comment: invited review, 36 figures, 900+ references; minor stylistic changes
from the published versio
HMG-CoAR expression in male breast cancer: relationship with hormone receptors, Hippo transducers and survival outcomes
Male breast cancer (MBC) is a rare hormone-driven disease often associated with obesity. HMG-CoAR is the central enzyme of the mevalonate pathway, a molecular route deputed to produce cholesterol and steroid-based hormones. HMG-CoAR regulates the oncogenic Hippo transducers TAZ/YAP whose expression was previously associated with shorter survival in MBC. 225 MBC samples were immunostained for HMG-CoAR and 124 were considered eligible for exploring its relationship with hormone receptors (ER, PgR, AR), Hippo transducers and survival outcomes. HMG-CoAR was positively associated with the expression of hormone receptors (ER, PgR, AR) and Hippo transducers. Overall survival was longer in patients with HMG-CoAR-positive tumors compared with their negative counterparts (p = 0.031). Five- and 10-year survival outcomes were better in patients whose tumors expressed HMG-CoAR (p = 0.044 and p = 0.043). Uni- and multivariate analyses for 10-year survival suggested that HMG-CoAR expression is a protective factor (HR 0.50, 95% CI: 0.25–0.99, p = 0.048 and HR 0.53, 95% CI: 0.26–1.07, p = 0.078). Results were confirmed in a sensitivity analysis by excluding uncommon histotypes (multivariate Cox: HR 0.45, 95% CI: 0.21–0.97, p = 0.043). A positive relationship emerged between HMG-CoAR, hormone receptors and TAZ/YAP, suggesting a connection between the mevalonate pathway, the hormonal milieu and Hippo in MBC. Moreover, HMG-CoAR expression may be a favorable prognostic indicator
Resources for sports engineering education
This paper serves as a resource guide for Sports Engineering educators. The paper covers key topics in Sports Engineering, including ball impact, friction, safety and materials. A variety of resource types are presented to reflect modern methods of learning and searching for information, including textbooks, research and review papers, websites and videos. The field could benefit from more resources specifically designated for teaching Sports Engineering, particularly textbooks
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