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We investigate the late-time Richtmyer–Meshkov instability (RMI) growth of sinuous perturbations on an air/sulphur hexafluoride interface (Atwood number,
$A \sim 0.67$
) subjected to a Mach 1.2 planar shock wave at Los Alamos National Laboratory's vertical shock tube facility. Interface perturbations are established using a novel membraneless technique where cross-flowing air and SF
separated by an oscillating splitter plate create a perturbed density interface. The interface formed has multi-modal features and residual small perturbations, however, a dominant mode is still noticeable. The late-time perturbation growths scale with
initial conditions (where
is the wavenumber and
is the initial amplitude of the dominant mode) as measured at the pre-shock interface. Past nonlinear models based on potential-flow theory, heuristic/interpolation approaches, Padé approximants and numerical simulations are evaluated against present experimental results. Accounting for an explicit
dependence in Sadot et al.'s (Phys. Rev. Lett., vol. 80, issue 8, 1998, pp. 1654–1657) model, we propose an empirical rational function that captures the asymptotic behaviour of perturbation growth for a broad range of initial conditions (
$0.30 \leq ka_0 \leq 0.86$
). The onset of mixing transition and its initial condition dependence are investigated with respect to the minimum state criterion (
$Re = 1.6 \times 10^5$
) for unsteady flows by Zhou (Phys. Plasmas, vol. 14, 2007, 082701). Earlier mixing transitions for higher
initial conditions are noted from local and global Reynolds number estimates which are corroborated by the existence of an inertial sub-range and formation of mixing regions indicating the physical significance of the minimum state criterion in RMI flows. The transition is accompanied by the increasing teapot-like appearance of joint probability density functions of
(invariants of the reduced velocity gradient tensor), establishing the technique as a useful tool for turbulence detection in two-dimensional diagnostics.
OBJECTIVES/GOALS: The goal of this project was to a) evaluate the first five years of Miami CTSI’s Pilot Translational and Clinical Studies Program using outcome measures that quantify research productivity augmented by the CTSA Common Metrics; and b) use the results to shape future program management. METHODS/STUDY POPULATION: Pilot Program applicant and awardee demographic data were collected during the first 5-year cycle of the Miami CTSI grant. Projects were categorized into the translation spectrum based on type of research using published guidelines. Research productivity from funded pilot projects were tracked annually using internal institutional grant award databases and external databases such as PubMed and NIH Reporter. CTSA Common Metrics were tracked using the Results Based Accountability framework. Relative Citation Ratio (RCR), NIH percentile and translation impact of pilot project publications were determined using the iCite tool (NIH Office of Portfolio Analysis). RESULTS/ANTICIPATED RESULTS: The Miami CTSI’s Pilot Award Program demonstrated notable success in its first five years. Of the twenty-two projects that were funded during that time period, 45% led to follow-on funding for a total of $17.2M—a strong return on investment of 15:1. Further, 77% of awardees had at least one publication. A total of four patents and 43 publications resulted directly from the funded projects. The mean RCR for all publications was 2.7, weighted RCR was 99.87, and nine papers were been cited by clinical documents. Overall, 63% of the projects were classified as T1/T2 (pre-clinical/clinical research) and 37% as T3/T4 (post-clinical translational research/public health). DISCUSSION/SIGNIFICANCE OF IMPACT: Miami CTSI’s Pilot Award Program demonstrated success in scholarly output, follow on funding, and scientific impact. These results will serve as benchmarks going forward and will allow the CTSI to leverage program strengths in collaborating with other institutional internal award mechanisms.
Capturing service users’ perspectives can highlight additional and different concerns to those of clinicians, but there are no up to date, self-report psychometrically sound measures of side effects of antipsychotic medications.
To develop a psychometrically sound measure to identify antipsychotic side effects important to service users, the Maudsley Side Effects (MSE) measure.
An initial item bank was subjected to a Delphi exercise (n = 9) with psychiatrists and pharmacists, followed by service user focus groups and expert panels (n = 15) to determine item relevance and language. Feasibility and comprehensive psychometric properties were established in two samples (N43 and N50). We investigated whether we could predict the three most important side effects for individuals from their frequency, severity and life impact.
MSE is a 53-item measure with good reliability and validity. Poorer mental and physical health, but not psychotic symptoms, was related to side-effect burden. Seventy-nine percent of items were chosen as one of the three most important effects. Severity, impact and distress only predicted ‘putting on weight’ which was more distressing, more severe and had more life impact in those for whom it was most important.
MSE is a self-report questionnaire that identifies reliably the side-effect burden as experienced by patients. Identifying key side effects important to patients can act as a starting point for joint decision making on the type and the dose of medication.
We studied the effect of a cross-conjugated bridging group (χC) on charge-transfer in a push-pull chromophore system. The hyperpolarizability of such molecules was found to be comparable to that of a fully π-conjugated molecule (πC) with the same donor and acceptor. The cross-conjugated moiety was then applied as a pendant to a fully π-conjugated chromophore containing a tricyanopyrroline acceptor (TCP). The addition of a χC moiety did not alter the intrinsic hyperpolarizability and provides an avenue for extending and aiding πC systems. The molecules were examined by X-ray diffraction (XRD), hyper-Raleigh scattering (HRS) and UV-visible (UV-vis) spectroscopy. Experimental results were compared with the predictions of density functional theory (DFT). Cross-conjugated molecules have comparable β values, relative to πC molecules, due to reduced spatial overlap between the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO). Thus, the χC architecture could facilitate independent modification of donor and acceptor strengths while minimizing unfavorable effects on electronic transitions and dipole moments.
The use of organic nonlinear optical (ONLO) materials in electro-optic (EO) modulators requires that the active molecular components (chromophores) be acentrically oriented. The fundamental molecular constituents are in a condensed, glassy phase. Molecular orientation in such systems is typically achieved by applying a DC poling field to the glassy material. We are developing efficient coarse-grained classical Monte Carlo (MC) methods to simulate the order of such systems. The most challenging aspects of these simulations are convergence to an experimentally relevant equilibrium ensemble and verification of simulation accuracy. We use a variety of molecular descriptions and a variety of MC methods to achieve proper order in the shortest number of computational cycles possible. Herein, we illustrate a few examples of the types of calculations and compare with experimental results with representative amorphous organic materials, including electro-optic chromophores.
Injurious pecking is a serious concern for commercial turkey production and
welfare. The behaviour is thought to represent re-directed ground foraging, but
the development and causes are poorly understood with little supporting
literature. In the initial development of the behaviour, early lighting regimes
and social facilitation may play contributing roles. Other factors such as the
availability of foraging material, diet composition, stocking densities, and
group dynamics may also affect levels of injurious pecking. Given that
commercial turkeys are group-housed, alternative breeding techniques, like group
selection based on social effects, might successfully reduce moralities from
pecking without detracting selection pressure from economic traits. However, to
better suit their behavioural needs, any genetic attempts to adapt turkeys to
perform less injurious pecking should be done in combination with environmental
and dietary improvements.
In November 2009, we initiated a multistate investigation of Salmonella Montevideo infections with pulsed-field gel electrophoresis pattern JIXX01.0011. We identified 272 cases in 44 states with illness onset dates ranging from 1 July 2009 to 14 April 2010. To help generate hypotheses, warehouse store membership card information was collected to identify products consumed by cases. These records identified 19 ill persons who purchased company A salami products before onset of illness. A case-control study was conducted. Ready-to-eat salami consumption was significantly associated with illness (matched odds ratio 8·5, 95% confidence interval 2·1–75·9). The outbreak strain was isolated from company A salami products from an environmental sample from one manufacturing plant, and sealed containers of black and red pepper at the facility. This outbreak illustrates the importance of using membership card information to assist in identifying suspect vehicles, the potential for spices to contaminate ready-to-eat products, and preventing raw ingredient contamination of these products.
In the study of materials at extreme pressures and temperatures, there is an enduring need to extend the range of experiments to previously inaccessible regimes. To accomplish this, improvements in diagnostics for in situ material characterization at extremes must proceed in parallel with techniques used to generate extreme states. Simultaneously, there is a need to study material phenomena – e.g. phase transformations and chemical reactions triggered by the application of extreme conditions – on their natural timescales. Here we report on recent developments in the application of ultrafast laser spectroscopic techniques to high-pressure hightemperature experiments on materials confined in a diamond-anvil cell. Using a bright broadband source coupled to ultrafast detection to discriminate signal from high thermal and fluorescent backgrounds, we conducted broadband optical spectroscopy up to 60 GPa and 1560 K. By coupling the broadband source to a monochromatic pulse, nonlinear Coherent Anti- Stokes Raman Spectroscopy (CARS) with high signal brightness was achieved. Optical absorption data in hot compressed O2 and CARS data in N2 at extreme pressures are reported.
Extracorporeal cardiopulmonary resuscitation may be defined as the use of extracorporeal membrane oxygenation for the support of patients who do not respond to conventional cardiopulmonary resuscitation. Data from national and international paediatric databases indicate that the use of extracorporeal cardiopulmonary resuscitation is increasing. Guidelines from the American Heart Association suggest that any patient with refractory cardiopulmonary resuscitation and potentially reversible causes of cardiac arrest is a candidate for extracorporeal cardiopulmonary resuscitation. One possible framework for selection of patients for extracorporeal cardiopulmonary resuscitation includes dividing patients on the basis of favourable or unfavourable characteristics. Favourable characteristics include cardiac disease, witnessed event in the intensive care unit, ability to deliver effective cardiopulmonary resuscitation, active patient monitoring present, favourable arterial blood gases, and early institution of extracorporeal membrane oxygenation. Unfavourable characteristics potentially include non-cardiac disease, an unwitnessed cardiac arrest, ineffective cardiopulmonary resuscitation, and severely acidotic arterial blood gases. Considering the significant resources and cost involved in the use of extracorporeal cardiopulmonary resuscitation, its use needs to be critically examined to improve outcomes, assess neurological recovery and quality of life, and help identify populations and other factors that may help guide in the selection of patients for successful extracorporeal cardiopulmonary resuscitation.
The use of extracorporeal membrane oxygenation in infants and children with cardiac disease who develop refractory cardiogenic shock, cyanosis, or cardiac arrest is increasing. Early mortality in children with cardiac disease who require extracorporeal membrane oxygenation remains an important issue, as only 40% of cannulated patients survive to discharge from the hospital. However, it is encouraging that 90% children who are discharged alive from the hospital after extracorporeal membrane oxygenation are still alive at intermediate-term follow-up. Surviving patients are at risk for long-term dysfunction of multiple organ systems related to their underlying cardiac disease, non-cardiac comorbidities, treatment-related complications, and exposure to extracorporeal membrane oxygenation. Among the most important acute complications related to support with extracorporeal membrane oxygenation is injury to the central nervous system, which may contribute to adverse neurodevelopmental outcomes. All of these factors, in turn, influence quality of life. Many survivors remain medically complex related to their underlying cardiac disease, comorbidities, and sequelae of complications acquired over their lifetime. Neurological morbidity clearly plays an important role in approximately one-third of survivors, with significant deficits in approximately 10%. The limited data about quality of life data that are available for survivors of cardiac extracorporeal membrane oxygenation suggests that approximately 15–30% of survivors have at least moderately decreased quality of life. Overall, published data support the ongoing use of support with extracorporeal membrane oxygenation in children with acute cardiac failure, most of whom would die without it. However, programmatic efforts to improve the selection of patients and the preservation of the function of end organs during extracorporeal membrane oxygenation are clearly needed in order to improve long-term outcomes.
We have chosen the name of GYES, one of the mythological giants with one hundred arms,
offspring of Gaia and Uranus, for our instrument study of a multifibre spectrograph for
the prime focus of the Canada-France-Hawaii Telescope. Such an instrument could provide an
excellent ground-based complement for the Gaia mission and a northern complement to the
HERMES project on the AAT. The CFHT is well known for providing a stable prime focus
environment, with a large field of view, which has hosted several imaging instruments, but
has never hosted a multifibre spectrograph. Building upon the experience gained at GÉPI
with FLAMES-Giraffe and X-Shooter, we are investigating the feasibility of a high
multiplex spectrograph (about 500 fibres) over a field of view one degree in diameter. We
are investigating an instrument with resolution in the range 15 000 to 30 000, which
should provide accurate chemical abundances for stars down to 16th magnitude and radial
velocities, accurate to 1 km s-1 for fainter stars. The study is led by
GÉPI-Observatoire de Paris with a contribution from Oxford for the study of the
positioner. The financing for the study comes from INSU CSAA and Observatoire de Paris.
The conceptual study will be delivered to CFHT for review by October 1st 2010.
Fasciolosis, caused by trematodes of the genus Fasciola, is an emerging disease of humans. One of the highest levels of human fasciolosis hepatica is found amongst the indigenous Aymaran people of the Northern Bolivian Altiplano. A meta-analysis of epidemiological surveys from 38 communities in the region demonstrates that fasciolosis has been endemic in the region since at least 1984 and is a zoonosis of rural communities. Human and bovine fasciolosis is associated with the communities lying in the plain from Lake Titicaca to La Paz, predominantly in the Los Andes province. In Los Andes incidences of up to 67% of population cohorts were found, and prevalence is age-related with the highest infection rate in children aged 8–11 years.
Fasciola hepatica secretes proteolytic enzymes and other molecules that are essential for host penetration and migration. This mixture may include enzymes required for the degradation of supramucosal gels, which defend epithelial surfaces against pathogen entry. These contain hydrated mucins that are heavily glycosylated. Excretory-secretory products (ES) from F. hepatica were examined for a range of glycosidase activities, using synthetic 4-methylumbelliferyl glycosides as substrates. The ES product contained at least 8 different glycosidase activities, the most abundant of which were β-N-acetylhexosaminidase, β-galactosidase and β-glucosidase. Alpha-fucosidase, β-glucuronidase, α-galactosidase, α-mannosidase and neuraminidase were also present. β-N-acetylhexosaminidase and β-galactosidase were present in multiple isoforms (at least 4), whereas β-glucosidase appeared to exist as one isoenzyme with a pI <3·8. All three enzymes had acidic pH optima (4·5–5·0). Ovine small intestinal mucin was degraded by ES at pH 4·5 or 7·0, with or without active cathepsin L, the major protease found in F. hepatica ES. The ability of F. hepatica ES to degrade mucin in the presence or absence of active cathepsin L suggests that cathepsin L is not essential for mucin degradation. The abundance of β-galactosidase and β-hexosaminidase in ES supports a role for these enzymes in mucin degradation.
A family of nonlinear optical chromophores has been synthesized containing novel donor systems based on functionalized guanidines. Chromophores utilizing these donor systems display superior transparency and stability properties. The unusual and highly desirable characteristics of these chromophores make them very promising candidates for electro-optic applications. Systematic study of the molecular hyperpolarizabilities and bulk electro-optic properties of polymers containing these chromophores is being used to guide optimization of these systems.
To eliminate the interface reaction problems between ferroelectric and semiconductor in MFS (metal-ferroelectric-semiconductor) as well as ferroelectric and insulator in MFIS (metal-ferroelectric-insulator-semiconductor) structures, a gate layer sandwich of the MFMIS (metal-ferroelectric-metal-insulator-semiconductor) is proposed. This structure consists of Pt-SBT-Pt-ZrO2-SiO2-Si stacks. In the MFMIS structure the MIS capacitor is separated from the ferroelectric MFM capacitor through a metal as a floating gate. Therefore, the MIS capacitor with SiO2 and ZrO2 as an insulator with excellent interface properties can be used and MFM acts as an ideal ferroelectric capacitor. As MFMIS is a series combination of MFM and MIS capacitors, it behaves as a voltage divider. The gate voltage is divided according to the capacitance ratio of the MIS and MFM structures. Since the fabricated devices have access to the floating gate, characteristics of the MFM and MIS capacitors can be determined independently to compare the characteristics of the MFMIS structure as a single capacitor. The ferroelectric can be programmed in one direction and the field effect due to that can be analyzed. The MFMIS structures showed significant memory window due to the polarization of ferroelectric thin films but the retention time was short. The short retention time was due to the depolarization field being larger than coercive field of the ferroelectric thin film.
In order to achieve the near-ferroelectric order desired in organic electro-optic (EO) chromophore systems, a pseudo-discotic chromophore is under investigation. Calculations suggest head-to-tail inter-chromophore dipole-dipole interactions should drive chromophores with an appropriate aspect ratio into ferroelectric columns similar to those seen in discotic liquid crystals (DLCs). Therefore, the liquid crystalline properties of these chromophores are being examined by differential scanning calorimetery (DSC), polarized optical microscopy (POM), and X-ray diffraction (XRD). Furthermore, the effect of this discotic behavior on the order and EO properties of the system are being examined both dynamically by second harmonic generation (SHG) and statically by attenuated total reflection (ATR). Additionally, these chromophores are being incorporated into waveguide-based photonic devices.
Previous research in organic electro-optics has shown dramatic increases in the hyperpolarizablity of NLO chromophores. However, this large microscopic activity has not been translated to the macroscopic domain. The polymeric electro-optic (E-O) materials continue to lack the high noncentrosymmetric order of the poled chromophores within the matrix necessary for high E-O response (r33). This deficiency of order represents one major obstacle that must be overcome before E-O device commercialization can be achieved. This lack of order is partially due to the large dipole moments of high μβ chromophores, which cause the chromophores to align in a centrosymmetric fashion through intermolecular electrostatic interactions. However, quantum calculations show that when the aspect ratio between the width and length of the chromophore system is adjusted to be greater than 1.4:1 by adding bulky side groups around the center of the chromophore, it would prevent side on pairing of the chromophores. This would cause a decrease in the large areas of centrosymmetric aggregation and thus allow for easier poling of the system. Here we report the synthesis of a nanoscale NLO architecture in which dendritic moieties have been incorporated around the center of the chromophore to give a three dimensional structure in order to achieve the 1.4:1 aspect ratio and maximize the macroscopic order of the system.