876 research outputs found

    Local and Global Distinguishability in Quantum Interferometry

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    A statistical distinguishability based on relative entropy characterises the fitness of quantum states for phase estimation. This criterion is employed in the context of a Mach-Zehnder interferometer and used to interpolate between two regimes, of local and global phase distinguishability. The scaling of distinguishability in these regimes with photon number is explored for various quantum states. It emerges that local distinguishability is dependent on a discrepancy between quantum and classical rotational energy. Our analysis demonstrates that the Heisenberg limit is the true upper limit for local phase sensitivity. Only the `NOON' states share this bound, but other states exhibit a better trade-off when comparing local and global phase regimes.Comment: 4 pages, in submission, minor revision

    Factors That Influence Medical Student Selection of an Emergency Medicine Residency Program: Implications for Training Programs

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    Objectives:  An understanding of student decision‐making when selecting an emergency medicine (EM) training program is essential for program directors as they enter interview season. To build upon preexisting knowledge, a survey was created to identify and prioritize the factors influencing candidate decision‐making of U.S. medical graduates. Methods:  This was a cross‐sectional, multi‐institutional study that anonymously surveyed U.S. allopathic applicants to EM training programs. It took place in the 3‐week period between the 2011 National Residency Matching Program (NRMP) rank list submission deadline and the announcement of match results. Results:  Of 1,525 invitations to participate, 870 candidates (57%) completed the survey. Overall, 96% of respondents stated that both geographic location and individual program characteristics were important to decision‐making, with approximately equal numbers favoring location when compared to those who favored program characteristics. The most important factors in this regard were preference for a particular geographic location (74.9%, 95% confidence interval [CI] = 72% to 78%) and to be close to spouse, significant other, or family (59.7%, 95% CI = 56% to 63%). Factors pertaining to geographic location tend to be out of the control of the program leadership. The most important program factors include the interview experience (48.9%, 95% CI = 46% to 52%), personal experience with the residents (48.5%, 95% CI = 45% to 52%), and academic reputation (44.9%, 95% CI = 42% to 48%). Unlike location, individual program factors are often either directly or somewhat under the control of the program leadership. Several other factors were ranked as the most important factor a disproportionate number of times, including a rotation in that emergency department (ED), orientation (academic vs. community), and duration of training (3‐year vs. 4‐year programs). For a subset of applicants, these factors had particular importance in overall decision‐making. Conclusions:  The vast majority of applicants to EM residency programs employed a balance of geographic location factors with individual program factors in selecting a residency program. Specific program characteristics represent the greatest opportunity to maximize the success of the immediate interview experience/season, while others provide potential for strategic planning over time. A working knowledge of these results empowers program directors to make informed decisions while providing an appreciation for the limitations in attracting applicants.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/91198/1/ACEM_1323_sm_DataSupplementS1.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/91198/2/j.1553-2712.2012.01323.x.pd

    Decimal Dilemmas: Interpreting and Addressing Misconceptions

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    In this article, a student's misconception of multiplication and division of decials is analyzed and findings are presented from preservice teachers’ interpretation of that misconception. The authors then highlight common decimal misconceptions, outline two strategies for addressing such misconceptions in the classroom, and include final remarks connecting the professional noticing framework with addressing misconceptions in mathematics

    Myogenic cell proliferation and generation of a reversible tumorigenic phenotype are triggered by preirradiation of the recipient site

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    Environmental influences have profound yet reversible effects on the behavior of resident cells. Earlier data have indicated that the amount of muscle formed from implanted myogenic cells is greatly augmented by prior irradiation (18 Gy) of the host mouse muscle. Here we confirm this phenomenon, showing that it varies between host mouse strains. However, it is unclear whether it is due to secretion of proliferative factors or reduction of antiproliferative agents. To investigate this further, we have exploited the observation that the immortal myogenic C2 C12 cell line forms tumors far more rapidly in irradiated than in nonirradiated host muscle. We show that the effect of preirradiation on tumor formation is persistent and dose dependent. However, C2 C12 cells are not irreversibly compelled to form undifferentiated tumor cells by the irradiated muscle environment and are still capable of forming large amounts of muscle when reimplanted into a nonirradiated muscle. In a clonal analysis of this effect, we discovered that C2 C12 cells have a bimodal propensity to form tumors; some clones form no tumors even after extensive periods in irradiated graft sites, whereas others rapidly form extensive tumors. This illustrates the subtle interplay between the phenotype of implanted cells and the factors in the muscle environment

    Mathematical description of bacterial traveling pulses

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    The Keller-Segel system has been widely proposed as a model for bacterial waves driven by chemotactic processes. Current experiments on {\em E. coli} have shown precise structure of traveling pulses. We present here an alternative mathematical description of traveling pulses at a macroscopic scale. This modeling task is complemented with numerical simulations in accordance with the experimental observations. Our model is derived from an accurate kinetic description of the mesoscopic run-and-tumble process performed by bacteria. This model can account for recent experimental observations with {\em E. coli}. Qualitative agreements include the asymmetry of the pulse and transition in the collective behaviour (clustered motion versus dispersion). In addition we can capture quantitatively the main characteristics of the pulse such as the speed and the relative size of tails. This work opens several experimental and theoretical perspectives. Coefficients at the macroscopic level are derived from considerations at the cellular scale. For instance the stiffness of the signal integration process turns out to have a strong effect on collective motion. Furthermore the bottom-up scaling allows to perform preliminary mathematical analysis and write efficient numerical schemes. This model is intended as a predictive tool for the investigation of bacterial collective motion

    Response to comment on 'Amphibian fungal panzootic causes catastrophic and ongoing loss of biodiversity'

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    Lambert et al. question our retrospective and holistic epidemiological assessment of the role of chytridiomycosis in amphibian declines. Their alternative assessment is narrow and provides an incomplete evaluation of evidence. Adopting this approach limits understanding of infectious disease impacts and hampers conservation efforts. We reaffirm that our study provides unambiguous evidence that chytridiomycosis has affected at least 501 amphibian species

    Assessment of low-dose cisplatin as a model of nausea and emesis in beagle dogs, potential for repeated administration

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    Cisplatin is a highly emetogenic cancer chemotherapy agent, which is often used to induce nausea and emesis in animal models. The cytotoxic properties of cisplatin also cause adverse events that negatively impact on animal welfare preventing repeated administration of cisplatin. In this study, we assessed whether a low (subclinical) dose of cisplatin could be utilized as a model of nausea and emesis in the dog while decreasing the severity of adverse events to allow repeated administration. The emetic, nausea-like behavior and potential biomarker response to both the clinical dose (70 mg/m2) and low dose (15 mg/m2) of cisplatin was assessed. Plasma creatinine concentrations and granulocyte counts were used to assess adverse effects on the kidneys and bone marrow, respectively. Nausea-like behavior and emesis was induced by both doses of cisplatin, but the latency to onset was greater in the low-dose group. No significant change in plasma creatinine was detected for either dose groups. Granulocytes were significantly reduced compared with baseline (P = 0.000) following the clinical, but not the low-dose cisplatin group. Tolerability of repeated administration was assessed with 4 administrations of an 18 mg/m2 dose cisplatin. Plasma creatinine did not change significantly. Cumulative effects on the granulocytes occurred, they were significantly decreased (P = 0.03) from baseline at 3 weeks following cisplatin for the 4th administration only. Our results suggest that subclinical doses (15 and 18 mg/m2) of cisplatin induce nausea-like behavior and emesis but have reduced adverse effects compared with the clinical dose allowing for repeated administration in crossover studies

    Statutory Assessment of the class? Supporting the additional needs of the learning context

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    This paper considers issues of funding of support for students facing difficulties in learning, and the role of assessment and labelling within this process. It explores the tensions within this process using a Foucauldian framework, and from the key perspectives of social justice and rights. Drawing on a range of literature it identifies the focus upon the individual within assessment processes around the world, and then considers in detail the strengths and weaknesses of the current form of Statutory Assessment of Special Educational Needs within England. The paper proposes an alternative funding system that resolves shortcomings within the individual approach and the English system. It suggests that a Class Funding Approach could build on a notion of justice for all, reduce the opportunities for wide variations in provision, and minimise the negative impact of current dividing practices
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