Optical black hole lasers

Using numerical simulations we show how to realise an optical black hole laser, i.e. an amplifier formed by travelling refractive index perturbations arranged so as to trap light between a white and a black hole horizon. The simulations highlight the main features of these lasers: the growth inside the cavity of positive and negative frequency modes accompanied by a weaker emission of modes that occurs in periodic bursts corresponding to the cavity round trips of the trapped modes. We then highlight a new regime in which the trapped mode spectra broaden until the zero-frequency points on the dispersion curve are reached. Amplification at the horizon is highest for zero-frequencies, therefore leading to a strong modification of the structure of the trapped light. For sufficiently long propagation times, lasing ensues only at the zero-frequency modes.Comment: accepted for publication in Classical and Quantum Gravit

La generalización del sistema foral

En España existen dos modelos de financiación autonómica; el sistema común y el sistema foral. Éste último, por como se ha definido el Cupo, genera más recursos per cápita que el sistema común y además da mayor capacidad para modificar algunos impuestos. En este trabajo, se analizará si las comunidades autónomas de régimen común resultarían beneficiadas o no con el sistema foral con los datos del año 2011. Para ello se calculan los recursos que tendría cada Comunidad Autónoma de régimen común si tuviera el sistema foral. Esto es, si recaudara todos los impuestos que actualmente recauda el Estado y pagara un Cupo. Estos recursos se comparan con los que obtiene ahora cada Comunidad Autónoma con el sistema común. Los resultados demuestran que las comunidades autónomas más ricas se beneficiarían con el sistema foral, mientras que las pobres saldrían perjudicadas. [ES

Improving Adherence to Daily Weight Orders on an Inpatient Pediatric Unit

Background: Weight is a crucial metric in the optimal care of pediatric patients in the inpatient setting. A patient’s weight is not only necessary for appropriate medication dosing, but is also often an indicator of fluid and nutritional status. As such, having a documented weight is integral to clinical decision making, and failure to obtain daily weight measurements when needed can result in delays in treatment and discharge plans. The importance of daily weight monitoring as well as the challenges surrounding good adherence to daily weight orders has long been recognized. There is currently no formal standardized process for obtaining daily weights on our inpatient pediatric unit, resulting in suboptimal adherence to daily weight orders. Methods: Our primary outcome measure is adherence to daily weight orders on our inpatient unit of Kravis Children’s Hospital 5th Floor, measured as the percentage of all patient-days for which a weight is recorded when there is an active daily weight order in the EMR. Baseline data was established through retrospective chart review of patients admitted to the unit prior to intervention. With the use of process mapping, we created interventions to standardize the method for obtaining weight measurements, to be implemented through standard PDSA cycles; our first intervention established an official time for weight measurements. Biweekly chart audits of all admitted patients were performed to monitor adherence to weight orders as well as identify further opportunities for improvement. We aim to implement 4 adjustments to our current weight measurement process, including further interventions aimed at weight ordering practices, nursing and PCA workflow, as well as continued education and reinforcement for staff. Results: We hypothesize that our intervention will increase adherence to daily weight orders through standardizing and streamlining the workflow to record daily weights. Preliminary baseline data showed that pre-intervention adherence to daily weight orders on Kravis Children’s Hospital 5th Floor was 73.8%. After our first PDSA cycle, preliminary data suggests improved adherence of 79%. There were also days when weights were obtained in the absence of a daily weight order, as well as days when a daily weight order was missing inappropriately. A balancing measure is to determine whether improved adherence to daily weight orders has any unintended or detrimental effects, such as decreased adherence to other types of weight orders at different frequencies (i.e. biweekly). Conclusions: Current adherence to daily weight orders on Kravis Children’s Hospital 5th Floor is inconsistent. Interventions that standardize the process of obtaining weight measurements in accordance with daily weight orders aims to improve adherence. Further directions may include investigating whether improved adherence to daily weight orders results in more clinically appropriate management, as well as identifying needs in standardizing weight ordering practices to only request measurements at frequencies appropriate for the admission diagnosis or clinical situation; minimizing clinically inappropriate daily weight orders may improve daily weight order adherence

Synthesis and characterization of H5decapa and related ligands

Radiopharmaceuticals have provided a great breakthrough in tumor imaging and treatment, and the continued exploration in the field is required to make their use widespread. This vast potential lies in the variety of the radioisotopes, due to the different emission profiles and half-lives, and it is the chemist’s job to harness these isotopes into functional pharmaceuticals. Bifunctional chelators (BFC), that incorporate a radiometal into a ligand scaffold that is functionalized to target a specific biological site, provide a mode to access many of these isotopes: α, β-, or auger electron emitters for therapy, β+ emitters for positron emission tomography (PET) imaging, and γ emitting isotopes for single photon emission computed tomography (SPECT) imaging. The first requirement of a BFC is the thermodynamic stability and kinetically inert complex it forms with the isotope, especially in vivo. The Orvig group has discovered the promise of the ligands H₂dedpa for ⁶⁷/⁶⁸Ga and H₄octapa for ¹¹¹In, and has thus led to the idea of expanding this scaffold for larger radioisotopes. An improved synthetic scheme for H₅decapa, a decadentate ligand, allowed for thermodynamic testing and radiolabeling experiments to be performed with ⁸⁹/⁹⁰Y, ¹⁷⁷Lu and ⁸⁹Zr. H₅decapa showed promising serum stability over 5 days with ¹⁷⁷Lu, and was able to quantitatively bind ⁸⁹Zr after 30 minutes at room temperature. A bifunctional version of H₅decapa was synthesised, coupling para-nitroethylbenzene to the central nitrogen, for future conjugation to biomolecules. As well, preliminary investigation into creating a version of H₅decapa with hydroxamate groups catered to binding Zr⁴⁺ was undertaken.Science, Faculty ofChemistry, Department ofGraduat

The Role of CASK in Neuronal Morphogenesis and Brain Size in Drosophila: A Genetic Model of Human Intellectual Disability with Microcephaly

CASK is a highly conserved gene with major roles in brain development and function. CASK encodes a multi-domain synaptic protein that interacts with numerous binding partners in at least three different subcellular regions. CASK is a member of the MAGUK protein family, defined by its carboxy-terminal end, which includes a guanylate kinase, PDZ and SH3 protein-interaction domains. CASK amino-terminal end, in turn, contains the CaMKinase-like domain, known as a pseudokinase. Highly expressed in neurons, CASK is localized to both pre- and post-synaptic zones, as well as to the nucleus. Mutations in human CASK cause X-linked intellectual disability (ID). There is a phenotypic spectrum of brain-development disorders caused by CASK mutations, that has been divided in two diagnostic categories. Microcephaly with pontine-cerebellar hypoplasia is the most severe, whereas FG syndrome-4 or X-linked ID with or without nystagmus cause the milder phenotype. Both of these phenotypes are accompanied by short stature. Because the CASK-mutant phenotypes in humans, I hypothesized that CASK is essential for neuronal morphogenesis. Therefore, I studied the role of Drosophila CASK in neuronal differentiation and brain development. I used the Drosophila CASK mutation, ∆18, an imprecise-excision allele that eliminates the full-length CASK protein, and the corresponding precise-excision control, Ex33. I examined neuronal morphogenesis in vitro by using primary cultures prepared from the whole CNS of wandering third instar larvae. Morphological parameters of neurite-arbor size and shape were quantified using NeuronMetricsTM software for semi-automated image analysis. CNS neurons lacking full-length CASK grew small arbors in vitro with an altered shape. This phenotype, called “bushy” combines small size (reduced length, higher-order branches, and area) with increased branch density. In addition, I found that CASK has a semi-dominant phenotype, by introducing a transgene with a WT copy of CASK the bushy phenotype was improved. To investigate whether CASK controls brain size, I studied brain morphology of Δ18 homozygous flies by histological examination of serial sections of osmium-stained, plastic-embedded pharate-adult heads. The volumes of brain and head were estimated using Olympus cellSens software. Brain and head estimated total volumes were significantly reduced in Δ18 homozygotes. Reduction in both brain and head indicates that flies have both microencephaly and microcephaly. In addition, I analyzed body size by measuring the pupal case length as a proxy for adult body size. CASK mutants have reduced body size. The small brain and reduced head found in Drosophila CASK mutants provide evidence that this is a good genetic model that parallels the CASK phenotypes in humans. In conclusion, these data suggest that the “small-brain” phenotype, associated with CASK-mutations in flies and microcephaly in children, results from decreased neuronal size and defective formation of dendritic arbors and axonal projections, rather than to a reduced number of neurons. These data strengthen the use of the Drosophila as a genetic model organism for modeling human developmental brain disorders. It would be reasonable to adapt the insights gained to develop new strategies in the field of human medicine, and its special significance regarding human CASK mutations. For instance, by performing a screen for drugs that can normalize disrupted neurons due to CASK disease-causing mutations, potential treatment strategies could be discovered.Release after 08/27/201

Optical black hole lasers

Using numerical simulations we show how to realize an optical black hole laser, i.e. an amplifier formed by travelling refractive index perturbations arranged so as to trap light between a white and a black hole horizons. The simulations highlight the main features of these lasers: the growth inside the cavity of positive and negative frequency modes accompanied by a weaker emission of modes that occurs in periodic bursts corresponding to the cavity round trips of the trapped modes. We then highlight a new regime in which the trapped mode spectra broaden until the zero-frequency points on the dispersion curve are reached. Amplification at the horizon is highest for zero-frequencies, therefore leading to a strong modification of the structure of the trapped light. For sufficiently long propagation times, lasing ensues only at the zero-frequency modes

A survey on dogs with valvular disease flying to Japan for operation

Abstract In small-breed dogs, myxomatous mitral valve disease (MMVD) is a common disease which may lead to chronic heart failure. Mitral valve repair is an optimal surgical treatment that is currently available in limited veterinary facilities globally because it requires a special surgery team and specific devices. Therefore, some dogs must travel overseas to undergo this surgery. However, a question arises regarding the safety of dogs when traveling by air with a heart disease. We aimed to evaluate the effect of flight journey on dogs with mitral valve disease, including survival rates, symptoms during the trip, laboratory test results, and operational outcomes. All dogs stayed near the owner in the cabin during the flight. The survival rate after the flight was 97.5% in 80 dogs. The surgical survival rates (96.0% and 94.3%) and hospitalization periods (7 days and 7 days) were similar between overseas and domestic dogs. This report shows that taking air flights in the cabin may not have a significant effect on dogs with MMVD, on the premise that their overall conditions are stable under cardiac medication