2,685 research outputs found
Doctor Mario: How Video Games Are Being Used as Medicine
The video game industry has become the largest media industry in the world, dwarfing even the movie and music industries. As such, video games are very present in the consciousness of American citizens. This makes them attractive to areas such as the field of medicine, which is always researching new and more effective ways to administer treatments to patients. This thesis examines all the research surrounding the use of video games as medicine, whether it be to treat a mental illness, physical ailment, or just for cognitive training, in an effort to determine if video games are effective as a treatment modality and determine the ideal way to introduce them into the field of medicine. Through an extensive literature review, this thesis determined that video games are, in fact, effective as treatments for various medical issues. Through an examination of the types of video games used in these studies, it was discovered that commercially-available video games are more common, as they are more attractive to doctors and researchers, offering an already existing, nearly endless pool of potential treatments. It was also concluded that the best way to introduce video games to medicine is by using them as a supplement to normal therapies and treatments, rather than as a standalone treatment
Circadian Rhythmic Localization of tPA and PAI-1 in the SCN 2.2 Cell Culture May Provide Evidence for Determining the Mechanism of Gating Photic Phase Shifts
Mammalian circadian rhythms are controlled by a central pacemaker located in the suprachiasmatic nucleus (SCN) of the brain. The SCN exhibits endogenous rhythms in neuronal activity and entrains to external stimuli, particularly light. Interestingly, phase shifts in response to light only occur at night and the mechanisms gating phase shifting are not well characterized. Our lab demonstrated that the extracellular protease, tissue-type plasminogen activator (tPA) and its inhibitor, plasminogen activator inhibitor (PAI-1), help gate phase shifting. Total tPA and PAI-1 expression are rhythmic in mouse SCN. These proteins mediate different functions depending on their exact subcellular localization. Therefore, knowing where they are located within the SCN will clarify their actions with respect to SCN clock phase regulation. The immortalized rat SCN2.2 cell culture exhibits rhythms in protein expression in vitro that mirror those found in vivo and can be separated into cellular, extracellular matrix, and media fractions. Here, we investigate tPA and PAI-1 expression using western blotting in the cellular fraction of the SCN2.2 line over a 36-hr timecourse. Preliminary results suggest a rhythm of PAI-1 levels inside the cell with peak expression in the early subjective night. Future studies are aimed toward elucidating the subcellular localization and temporal expression patterns of these proteins in the SCN
Line junction in a quantum Hall system with two filling fractions
We present a microscopic model for a line junction formed by counter or
co-propagating single mode quantum Hall edges corresponding to different
filling factors. The ends of the line junction can be described by two possible
current splitting matrices which are dictated by the conditions of both lack of
dissipation and the existence of a linear relation between the bosonic fields.
Tunneling between the two edges of the line junction then leads to a
microscopic understanding of a phenomenological description of line junctions
introduced some time ago. The effect of density-density interactions between
the two edges is considered, and renormalization group ideas are used to study
how the tunneling parameter changes with the length scale. This leads to a
power law variation of the conductance of the line junction with the
temperature. Depending on the strength of the interactions the line junction
can exhibit two quite different behaviors. Our results can be tested in bent
quantum Hall systems fabricated recently.Comment: 9 pages including 4 figure
Fluctuation-Driven Molecular Transport in an Asymmetric Membrane Channel
Channel proteins, that selectively conduct molecules across cell membranes,
often exhibit an asymmetric structure. By means of a stochastic model, we argue
that channel asymmetry in the presence of non-equilibrium fluctuations, fueled
by the cell's metabolism as observed recently, can dramatically influence the
transport through such channels by a ratchet-like mechanism. For an
aquaglyceroporin that conducts water and glycerol we show that a previously
determined asymmetric glycerol potential leads to enhanced inward transport of
glycerol, but for unfavorably high glycerol concentrations also to enhanced
outward transport that protects a cell against poisoning.Comment: REVTeX4, 4 pages, 3 figures; Accepted for publication in Phys. Rev.
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Real-time observations of single bacteriophage λ DNA ejections in vitro
The physical, chemical, and structural features of bacteriophage genome release have been the subject of much recent attention. Many theoretical and experimental studies have centered on the internal forces driving the ejection process. Recently, Mangenot et al. [Mangenot S, Hochrein M, Rädler J, Letellier L (2005) Curr Biol 15:430–435.] reported fluorescence microscopy of phage T5 ejections, which proceeded stepwise between DNA nicks, reaching a translocation speed of 75 kbp/s or higher. It is still unknown how high the speed actually is. This paper reports real-time measurements of ejection from phage {lambda}, revealing how the speed depends on key physical parameters such as genome length and ionic state of the buffer. Except for a pause before DNA is finally released, the entire 48.5-kbp genome is translocated in {approx}1.5 s without interruption, reaching a speed of 60 kbp/s. The process gives insights particularly into the effects of two parameters: a shorter genome length results in lower speed but a shorter total time, and the presence of divalent magnesium ions (replacing sodium) reduces the pressure, increasing ejection time to 8–11 s. Pressure caused by DNA–DNA interactions within the head affects the initiation of ejection, but the close packing is also the dominant source of friction: more tightly packed phages initiate ejection earlier, but with a lower initial speed. The details of ejection revealed in this study are probably generic features of DNA translocation in bacteriophages and have implications for the dynamics of DNA in other biological systems
Dynamics of Nucleation in the Ising Model
Reactive pathways to nucleation in a three-dimensional Ising model at 60% of
the critical temperature are studied using transition path sampling of single
spin flip Monte Carlo dynamics. Analysis of the transition state ensemble (TSE)
indicates that the critical nuclei are rough and anisotropic. The TSE,
projected onto the free energy surface characterized by cluster size, N, and
surface area, S, indicates the significance of other variables in addition to
these two traditional reaction coordinates for nucleation. The transmission
coefficient along N is ~ 0.35, and this reduction of the transmission
coefficient from unity is explained in terms of the stochastic nature of the
dynamic model.Comment: In press at the Journal of Physical Chemistry B, 7 pages, 8 figure
Aluminum arsenide cleaved-edge overgrown quantum wires
We report conductance measurements in quantum wires made of aluminum
arsenide, a heavy-mass, multi-valley one-dimensional (1D) system. Zero-bias
conductance steps are observed as the electron density in the wire is lowered,
with additional steps observable upon applying a finite dc bias. We attribute
these steps to depopulation of successive 1D subbands. The quantum conductance
is substantially reduced with respect to the anticipated value for a spin- and
valley-degenerate 1D system. This reduction is consistent with
disorder-induced, intra-wire backscattering which suppresses the transmission
of 1D modes. Calculations are presented to demonstrate the role of strain in
the 1D states of this cleaved-edge structure.Comment: Submitted to Applied Physics Letter
Mainstreaming ecosystem science in spatial planning practice : exploiting a hybrid opportunity space
This paper develops a framework for improved mainstreaming of ecosystem science in policy and decision-making within a spatial planning context. Ecosystem science is advanced as a collective umbrella to capture a body of work and approaches rooted in social-ecological systems thinking, spawning a distinctive ecosystem terminology: ecosystem approach, ecosystem services, ecosystem services framework and natural capital. The interface between spatial planning and ecosystem science is explored as a theoretical opportunity space to improve mainstreaming processes adapting Rogers’ (2003) diffusion model. We introduce the twin concepts of hooks (linking ecosystem science to a key policy or legislative term, duty or priority that relate to a particular user group) and ‘bridges’ (linking ecosystem science to a term, concept or policy priority that is used and readily understood across multiple groups and publics) as translational mechanisms in transdisciplinary mainstreaming settings. We argue that ecosystem science can be embedded into the existing work priorities and vocabularies of spatial planning practice using these hooks and bridges. The resultant framework for mainstreaming is then tested, drawing on research funded as part of the UK National Ecosystem Assessment Follow-On programme (2012-2014), within 4 case studies; each reflecting different capacities, capabilities, opportunities and barriers. The results reveal the importance of leadership, political buy in, willingness to experiment outside established comfort zones and social learning as core drivers supporting mainstreaming processes. Whilst there are still significant challenges in mainstreaming in spatial planning settings, the identification and use of hooks and bridges collectively, enables traction to be gained for further advances; moving beyond the status quo to generate additionality and potential behaviour change within different modes of mainstreaming practice. This pragmatic approach has global application to help improve the way nature is respected and taken account of in planning systems nationally and globally
Classical-to-stochastic Coulomb blockade cross-over in aluminum arsenide wires
We report low-temperature differential conductance measurements in aluminum
arsenide cleaved-edge overgrown quantum wires in the pinch-off regime. At zero
source-drain bias we observe Coulomb blockade conductance resonances that
become vanishingly small as the temperature is lowered below . We
show that this behavior can be interpreted as a classical-to-stochastic Coulomb
blockade cross-over in a series of asymmetric quantum dots, and offer a
quantitative analysis of the temperature-dependence of the resonances
lineshape. The conductance behavior at large source-drain bias is suggestive of
the charge density wave conduction expected for a chain of quantum dots.Comment: version 2: new figure 4, refined discussio
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