36 results
Incompressible active phases at an interface. Part 1. Formulation and axisymmetric odd flows
- Leroy L. Jia, William T.M. Irvine, Michael J. Shelley
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- Journal:
- Journal of Fluid Mechanics / Volume 951 / 25 November 2022
- Published online by Cambridge University Press:
- 08 November 2022, A36
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Inspired by the recent realization of a two-dimensional (2-D) chiral fluid as an active monolayer droplet moving atop a 3-D Stokesian fluid, we formulate mathematically its free-boundary dynamics. The surface droplet is described as a general 2-D linear, incompressible and isotropic fluid, having a viscous shear stress, an active chiral driving stress and a Hall stress allowed by the lack of time-reversal symmetry. The droplet interacts with itself through its driven internal mechanics and by driving flows in the underlying 3-D Stokes phase. We pose the dynamics as the solution to a singular integral–differential equation, over the droplet surface, using the mapping from surface stress to surface velocity for the 3-D Stokes equations. Specializing to the case of axisymmetric droplets, exact representations for the chiral surface flow are given in terms of solutions to a singular integral equation, solved using both analytical and numerical techniques. For a disc-shaped monolayer, we additionally employ a semi-analytical solution that hinges on an orthogonal basis of Bessel functions and allows for efficient computation of the monolayer velocity field, which ranges from a nearly solid-body rotation to a unidirectional edge current, depending on the subphase depth and the Saffman–Delbrück length. Except in the near-wall limit, these solutions have divergent surface shear stresses at droplet boundaries, a signature of systems with codimension-one domains embedded in a 3-D medium. We further investigate the effect of a Hall viscosity, which couples radial and transverse surface velocity components, on the dynamics of a closing cavity. Hall stresses are seen to drive inward radial motion, even in the absence of edge tension.
The role of monolayer viscosity in Langmuir film hole closure dynamics
- Leroy L. Jia, Michael J. Shelley
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- Journal:
- Journal of Fluid Mechanics / Volume 948 / 10 October 2022
- Published online by Cambridge University Press:
- 02 September 2022, A1
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We re-examine the model proposed by Alexander et al. (Phys. Fluids, vol. 18, 2006, 062103) for the closing of a circular hole in a molecularly thin incompressible Langmuir film situated on a Stokesian subfluid. For simplicity their model assumes that the surface phase is inviscid which leads to the result that the cavity area decreases at a constant rate determined by the ratio of edge tension to subfluid viscosity. We reformulate the problem, allowing for a regularising monolayer viscosity. The viscosity-dependent corrections to the hole dynamics are analysed and found to be non-trivial, even when the monolayer viscosity is small; these corrections may explain the departure of experimental data from the theoretical prediction when the hole radius becomes comparable to the Saffman–Delbrück length. Through fitting, under these relaxed assumptions, we find the edge tension could be as much as six times larger ($\sim$4.0 pN) than reported previously.
No More Nations Within Nations: Indigenous Sovereignty after the End of Treaty-Making in 1871
- Joel T. Helfrich, Michael Leroy Oberg, Alaina E. Roberts, Julie L. Reed, Kevin Bruyneel
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- Journal:
- The Journal of the Gilded Age and Progressive Era / Volume 20 / Issue 2 / April 2021
- Published online by Cambridge University Press:
- 22 April 2021, pp. 325-329
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- April 2021
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Pilot study of a combined genomic and epidemiologic surveillance program for hospital-acquired multidrug-resistant pathogens across multiple hospital networks in Australia
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- Norelle L. Sherry, Robyn S. Lee, Claire L. Gorrie, Jason C. Kwong, Rhonda L. Stuart, Tony M. Korman, Caroline Marshall, Charlie Higgs, Hiu Tat Chan, Maryza Graham, Paul D.R. Johnson, Marcel J. Leroi, Caroline Reed, Michael J. Richards, Monica A. Slavin, Leon J. Worth, Benjamin P. Howden, M. Lindsay Grayson
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- Journal:
- Infection Control & Hospital Epidemiology / Volume 42 / Issue 5 / May 2021
- Published online by Cambridge University Press:
- 26 November 2020, pp. 573-581
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- May 2021
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Objectives:
To conduct a pilot study implementing combined genomic and epidemiologic surveillance for hospital-acquired multidrug-resistant organisms (MDROs) to predict transmission between patients and to estimate the local burden of MDRO transmission.
Design:Pilot prospective multicenter surveillance study.
Setting:The study was conducted in 8 university hospitals (2,800 beds total) in Melbourne, Australia (population 4.8 million), including 4 acute-care, 1 specialist cancer care, and 3 subacute-care hospitals.
Methods:All clinical and screening isolates from hospital inpatients (April 24 to June 18, 2017) were collected for 6 MDROs: vanA VRE, MRSA, ESBL Escherichia coli (ESBL-Ec) and Klebsiella pneumoniae (ESBL-Kp), and carbapenem-resistant Pseudomonas aeruginosa (CRPa) and Acinetobacter baumannii (CRAb). Isolates were analyzed and reported as routine by hospital laboratories, underwent whole-genome sequencing at the central laboratory, and were analyzed using open-source bioinformatic tools. MDRO burden and transmission were assessed using combined genomic and epidemiologic data.
Results:In total, 408 isolates were collected from 358 patients; 47.5% were screening isolates. ESBL-Ec was most common (52.5%), then MRSA (21.6%), vanA VRE (15.7%), and ESBL-Kp (7.6%). Most MDROs (88.3%) were isolated from patients with recent healthcare exposure.
Combining genomics and epidemiology identified that at least 27.1% of MDROs were likely acquired in a hospital; most of these transmission events would not have been detected without genomics. The highest proportion of transmission occurred with vanA VRE (88.4% of patients).
Conclusions:Genomic and epidemiologic data from multiple institutions can feasibly be combined prospectively, providing substantial insights into the burden and distribution of MDROs, including in-hospital transmission. This analysis enables infection control teams to target interventions more effectively.
Codium-like taxa from the Silurian of North America: morphology, taxonomy, paleoecology, and phylogenetic affinity
- Steven T. LoDuca, Anthony L. Swinehart, Matthew A. LeRoy, Denis K. Tetreault, Shawn Steckenfinger
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- Journal:
- Journal of Paleontology / Volume 95 / Issue 2 / March 2021
- Published online by Cambridge University Press:
- 29 October 2020, pp. 207-235
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A 1901 report by the Smithsonian Custodian of Paleozoic Plants noted that the nonbiomineralized taxa Buthotrephis divaricata White, 1901, B. newlini White, 1901, and B. lesquereuxi Grote and Pitt, 1876, from the upper Silurian of the Great Lakes area, shared key characteristics in common with the extant green macroalga Codium. A detailed reexamination of these Codium-like taxa and similar forms from the lower Silurian of Ontario, New York, and Michigan, including newly collected material of Thalassocystis striata Taggart and Parker, 1976, aided by scanning electron microscopy and stable carbon isotope analysis, provides new data in support of an algal affinity. Crucially, as with Codium, the originally cylindrical axes of all of these taxa consist of a complex internal array of tubes divided into distinct medullary and cortical regions, the medullary tubes being arranged in a manner similar to those of living Pseudocodium. In view of these findings, the three study taxa originally assigned to Buthotrephis, together with Chondrites verus Ruedemann, 1925, are transferred to the new algal taxon Inocladus new genus, thereby establishing Inocladus lesquereuxi new combination, Inocladus newlini new comb., Inocladus divaricata new comb., and Inocladus verus new comb. Morphological and paleoecological data point to a phylogenetic affinity for Inocladus n. gen. and Thalassocystis within the Codium-bearing green algal order Bryopsidales, but perhaps nested within an extinct lineage. Collectively, this material fits within a large-scale pattern of major macroalgal morphological diversification initiated in concert with the Great Ordovician Biodiversification Event and apparently driven by a marked escalation in grazing pressure.
UUID: http://zoobank.org/97c5c737-b291-41a2-aceb-f398cac9537a
How do we improve adolescent diet and physical activity in India and sub-Saharan Africa? Findings from the Transforming Adolescent Lives through Nutrition (TALENT) consortium
- ME Barker, P Hardy-Johnson, S Weller, A Haileamalak, L Jarju, J Jesson, GV Krishnaveni, K Kumaran, V Leroy, SE Moore, SA Norris, S Patil, SA Sahariah, K Ward, CS Yajnik, CHD Fall
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- Journal:
- Public Health Nutrition / Volume 24 / Issue 16 / November 2021
- Published online by Cambridge University Press:
- 28 October 2020, pp. 5309-5317
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Objective:
Adolescent diet, physical activity and nutritional status are generally known to be sub-optimal. This is an introduction to a special issue of papers devoted to exploring factors affecting diet and physical activity in adolescents, including food insecure and vulnerable groups.
SettingEight settings including urban, peri-urban and rural across sites from five different low- and middle-income countries.
Design:Focus groups with adolescents and caregivers carried out by trained researchers.
Results:Our results show that adolescents, even in poor settings, know about healthy diet and lifestyles. They want to have energy, feel happy, look good and live longer, but their desire for autonomy, a need to ‘belong’ in their peer group, plus vulnerability to marketing exploiting their aspirations, leads them to make unhealthy choices. They describe significant gender, culture and context-specific barriers. For example, urban adolescents had easy access to energy dense, unhealthy foods bought outside the home, whereas junk foods were only beginning to permeate rural sites. Among adolescents in Indian sites, pressure to excel in exams meant that academic studies were squeezing out physical activity time.
Conclusions:Interventions to improve adolescents’ diets and physical activity levels must therefore address structural and environmental issues and influences in their homes and schools, since it is clear that their food and activity choices are the product of an interacting complex of factors. In the next phase of work, the Transforming Adolescent Lives through Nutrition consortium will employ groups of adolescents, caregivers and local stakeholders in each site to develop interventions to improve adolescent nutritional status.
Optimizing Scarce Resource Allocation During COVID-19: Rapid Creation of a Regional Health-Care Coalition and Triage Teams in San Diego County, California
- Asha Devereaux, Holly Yang, Gilbert Seda, Viji Sankar, Ryan C. Maves, Navaz Karanjia, John Scott Parrish, Christy Rosenberg, Paula Goodman-Crews, Lynette Cederquist, Frederick M. Burkle, Jr., Jennifer Tuteur, Chiara Leroy, Kristi L. Koenig
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- Journal:
- Disaster Medicine and Public Health Preparedness / Volume 16 / Issue 1 / February 2022
- Published online by Cambridge University Press:
- 10 September 2020, pp. 321-327
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Successful management of an event where health-care needs exceed regional health-care capacity requires coordinated strategies for scarce resource allocation. Publications for rapid development, training, and coordination of regional hospital triage teams to manage the allocation of scarce resources during coronavirus disease 2019 (COVID-19) are lacking. Over a period of 3 weeks, over 100 clinicians, ethicists, leaders, and public health authorities convened virtually to achieve consensus on how best to save the most lives possible and share resources. This is referred to as population-based crisis management. The rapid regionalization of 22 acute care hospitals across 4500 square miles in the midst of a pandemic with a shifting regulatory landscape was challenging, but overcome by mutual trust, transparency, and confidence in the public health authority. Because many cities are facing COVID-19 surges, we share a process for successful rapid formation of health-care care coalitions, Crisis Standard of Care, and training of Triage Teams. Incorporation of continuous process improvement and methods for communication is essential for successful implementation. Use of our regional health-care coalition communications, incident command system, and the crisis care committee helped mitigate crisis care in the San Diego and Imperial County region as COVID-19 cases surged and scarce resource collaborative decisions were required.
Imaging Usual Addictions: Tobacco, Canabis and Alcohol
- C. Leroy, S. Chanraud, E. Artiges, C. Martelli, A. Cachia, J. Andoh, N. Kostogianni, Y. Berlin, M. Reynaud, H.J. Aubin, C. Trichard, J.-L. Martinot
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- Journal:
- European Psychiatry / Volume 24 / Issue S1 / January 2009
- Published online by Cambridge University Press:
- 16 April 2020, 24-E174
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Background:
Brain models of drug addiction are being tackled in humans, using PET and MRI.
Results:1. Whereas tobacco and cannabis do not interact directly with dopamine sites, positron emission tomography detected lower availability in sites regulating the catecholamines homeostasis, notably in dopamine transporter sites in striatal and in extrastriatal regions. This further supports repeated and long term substance use progress towards an adaptative diminished basal dopamine level that would contribute to the switch to an addicted brain.
2. Alcohol: abnormalities in brain macro- and micro- structure were searched in detoxified alcohol-dependents with preserved psychosocial functioning:
- Brain function (fMRI): fronto-cerebellar overactivation detected during an auditory language task in alcohol-dependents may reflect the compensatory effort required for patients to maintain the same level of performance as controls.
- Brain macrostructure (MRI). Widespread lower white matter volumes, and lower grey matter volumes in the frontal lobe, insula, hippocampus, thalami and cerebellum, were detected. Poorer neuropsychological performance correlated with smaller grey matter volumes in these regions and with lower white matter volume in the brainstem.
- Brain microstructure (DTI): tractography of white matter fiber bundles revealed that brainstem bundles alteration may contribute to cognitive flexibility impairment. Regression analyses showed memory scores were related to brain microstructure in parahippocampal areas, frontal cortex, and left temporal cortex. This suggest diffusion imaging (DTI) is a useful probe to early alcohol-induced brain alterations.
Conclusion:While indices of dopamine down-regulation are consistency detected in several drug addictions, even “socially-adapted” alcohol dependence may induce change in brain structure.
Psychol Med. 1998 28:1039-48.
Neuropsychopharmacology. 2007 32:429-38.
IEEE Trans Med Imaging. 2007 26:553-65
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Neuropsychopharmacology (Chanraud S et al., 2008 Jul 9. [Epub ahead of print]).
J Clin Psychopharmacol (Leroy C et al, in press).
Imaging treatment changes in chronic patients and confounding factors
- J.-L. Martinot, E. Artiges, C. Leroy, M.-L. Paillère Martinot, S. Mana, L. Karila, A. Galinowski, R. De Beaurepaire, C. Trichard
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- European Psychiatry / Volume 26 / Issue S2 / March 2011
- Published online by Cambridge University Press:
- 16 April 2020, p. 2154
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1/In juvenile patients, a cross-sectional ALE meta-analysis of both brain structure and function regional deviations in 270 articles allowed to cluster the diagnosed disorders into three sets with respectively marked affective, cognitive, and psychomotor phenomenology. The group with affective phenomenology was characterized by abnormalities of the frontal-limbic regions; the group with “cognition deficits” (incl. schizophrenia) mainly related to cortex abnormalities; and the psychomotor condition was associated with abnormalities in the basal ganglia. Therefore, early regional brain abnormalities might interact with the analysis of subsequent treatments effects in MR studies of brain structure and function of chronic mental disorders. 2/In chronic patients, brain imaging studies of antipsychotic drugs using dopamine receptor radioligands &PET scanner have consistently demonstrated the prevalence of their dose-dependent action in basal ganglia. This information has led to theoretical windows for optimal drug dosage. Recent measures of the dopamine transporter in chronic antipsychotic treatment, or in chronic use of drugs of addiction (e.g. tobacco, cannabis) suggest opposite changes of the adioligand uptake in both conditions. Therefore, control for the associated confounding addictions is required for in vivo analysis of antipsychotic action on the dopamine regulation in cortex and subcortical regions. 3/In treatment-resistant patients, MR & PET imaging studies have detected deviations of both brain structure and function, therefore suggesting biomarker of treatment response. 4/Conclusion: stage of illness, addictions, multimodal imaging, should be considered as covariates for brain imaging determinations of treatment effects in patients with chronic mental disorders.
Hepatitis C subtype distribution in chronically infected patients with mild liver fibrosis in France: the GEMHEP study
- T. Semenova, B. Nemoz, V. Thibault, G. Lagathu, G. Duverlie, E. Brochot, P. Trimoulet, C. Payan, S. Vallet, C. Henquell, S. Chevaliez, M. Bouvier-Alias, S. Maylin, A-M. Roque-Afonso, L. Izquierdo, F. Lunel-Fabiani, P. Marcellin, P. Morand, V. Leroy, S. Larrat
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- Journal:
- Epidemiology & Infection / Volume 147 / 2019
- Published online by Cambridge University Press:
- 10 July 2019, e234
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Treatment options for Hepatitis C infection have greatly improved with direct-acting antiviral (DAA) combinations achieving high cure rates. Nevertheless, the cost of this treatment is still high and access to treatment in many countries has been preferentially reserved for patients with more severe fibrosis (F3 and F4). In this French nationwide study, we investigated the epidemiological characteristics and genotype distribution of hepatitis C virus (HCV) in treatment-naive patients with METAVIR fibrosis stages between F0 and F2 in order to identify patient profiles that became eligible for unrestricted treatment in a second period. Between 2015 and 2016 we collected data from nine French university hospitals on a total of 584 HCV positive patients with absent, mild or moderate liver fibrosis. The most represented genotypes were genotype 1b (159/584; 27.2%), followed by genotype 1a (150/584; 25.7%); genotype 3 (87/584: 14.9%); genotype 4 (80/584; 13.7%). Among genotype 4: 4a was predominantly encountered with 22 patients (27.5% of genotype 4). Genotypes 1b and 1a are currently the most frequent virus types present in treatment-naive patients with mild fibrosis in France. They can be readily cured using the available DAA. Nevertheless, non-a/non-d genotype 4 is also frequent in this population and clinical data on the efficacy of DAA on these subtypes is missing. The GEMHEP is the French group for study and evaluation of viral hepatitis on a national scale. Data collection on epidemiological and molecular aspects of viral hepatitis is performed on a regular basis in all main French teaching hospitals and serves as a basis for surveillance of these infections. Analysis and trends are regularly published on behalf of the GEMHEP group. Data collection was performed retrospectively over the 2015–2016 period, covering nine main university hospitals in France. A total of 584 hepatitis C positive patients were included in this study. Genotyping of the circulating viruses showed a high prevalence of genotypes 1b and 1a in our population. The epidemiology of hepatitis C is slowly changing in France, particularly as a consequence of the rise of ‘non-a non-d’ genotype 4 viruses mainly originating from African populations. More data concerning treatment efficacy of these genotypes is needed in order to guide clinical care.
Device for Collecting Uncontaminated Soil Samples in Plastic Tubing
- Oscar E. Schubert, LeRoy P. Stevens, Freddie L. Alt
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- Weed Science / Volume 31 / Issue 3 / May 1983
- Published online by Cambridge University Press:
- 12 June 2017, pp. 401-403
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A three-piece soil-sampling device was constructed to collect soil cores in polyvinyl chloride tubing to a depth of 92 cm with no or minimum contamination. The device with tube is driven into the soil with a hydraulic post-driver and removed with a chain attached to the bucket of a front-end loader on a tractor. Various depths can be sampled for analysis by cutting off proportionate sections of the tubing containing the soil core. This procedure is more rapid and poses less chance of contamination than by taking progressively deeper soil samples.
On the Variation of Gas Depletion Time
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- D. Utomo, L. Blitz, A. Bolatto, T. Wong, A. Leroy, S. Vogel, EDGE-CALIFA Collaboration
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- Journal:
- Proceedings of the International Astronomical Union / Volume 11 / Issue S315 / August 2015
- Published online by Cambridge University Press:
- 12 September 2016, pp. 258-261
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- August 2015
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We present an updated status of the EDGE project, which is a survey of 125 local galaxies in the 12CO(1−0) and 13CO(1−0) lines. We combine the molecular data of the EDGE survey with the stellar and ionized gas maps of the CALIFA survey to give a comprehensive view of the dependence of the star formation efficiency, or equivalently, the molecular gas depletion time, on various local environments, such as the stellar surface density, metallicity, and radius from the galaxy center. This study will provide insight into the parameters that drive the star formation efficiency in galaxies at z ~ 0.
Fossil avian eggs from the Palaeogene of southern France: new size estimates and a possible taxonomic identification of the egg-layer
- D. ANGST, E. BUFFETAUT, C. LÉCUYER, R. AMIOT, F. SMEKTALA, S. GINER, A. MÉCHIN, P. MÉCHIN, A. AMOROS, L. LEROY, M. GUIOMAR, H. TONG, A. MARTINEZ
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- Journal:
- Geological Magazine / Volume 152 / Issue 1 / January 2015
- Published online by Cambridge University Press:
- 24 April 2014, pp. 70-79
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Eggshell fragments attributed to large birds have been known from the Palaeogene of southern France for half a century, but reconstructing their original dimensions and identifying the birds that laid the eggs has been fraught with difficulties. On the basis of numerous newly collected specimens and using geometrical calculations, the original size of the thick-shelled eggs is reconstructed, showing that they were slightly larger than ostrich eggs, with a greatest length of 17.8 cm and a mean diameter of 12.0 cm in transversal section. The estimated volume is 1330.4 cm3. The fossil eggs from southern France are thus among the largest known avian eggs, being only surpassed by Aepyornis and some moas. Estimated egg mass is about 1.4 kg. On the basis of egg mass, the body mass of the parent bird is estimated at between 135.4 kg and 156.4 kg, assuming that the hatchlings were precocial. These calculations are in good agreement with the dimensions and mass estimates for the Palaeogene giant bird Gastornis, a probable anseriform, which lived in Europe at the time the eggs were laid. Other large Early Tertiary birds from Europe (Remiornis, Palaeotis) are too small to have laid these eggs. In all likelihood, the large eggs from the Palaeogene of southern France were laid by gastornithid birds.
Effects of parity and periconceptional metabolic state of Holstein–Friesian dams on the glucose metabolism and conformation in their newborn calves
- P. Bossaert, E. Fransen, A. Langbeen, M. Stalpaert, I. Vandenbroeck, P. E. Bols, J. L. Leroy
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The metabolic state of pregnant mammals influences the offspring’s development and risk of metabolic disease in postnatal life. The metabolic state in a lactating dairy cow differs immensely from that in a non-lactating heifer around the time of conception, but consequences for their calves are poorly understood. The hypothesis of this study was that differences in metabolic state between non-lactating heifers and lactating cows during early pregnancy would affect insulin-dependent glucose metabolism and development in their neonatal calves. Using a mixed linear model, concentrations of glucose, IGF-I and non-esterified fatty acids (NEFAs) were compared between 13 non-lactating heifers and 16 high-yielding dairy cows in repeated blood samples obtained during the 1st month after successful insemination. Calves born from these dams were weighed and measured at birth, and subjected to intravenous glucose and insulin challenges between 7 and 14 days of age. Eight estimators of insulin-dependent glucose metabolism were determined: glucose and insulin peak concentration, area under the curve and elimination rate after glucose challenge, glucose reduction rate after insulin challenge, and quantitative insulin sensitivity check index. Effects of dam parity and calf sex on the metabolic and developmental traits were analysed in a two-way ANOVA. Compared with heifers, cows displayed lower glucose and IGF-I and higher NEFA concentrations during the 1st month after conception. However, these differences did not affect developmental traits and glucose homeostasis in their calves: birth weight, withers height, heart girth, and responses to glucose and insulin challenges in the calves were unaffected by their dam’s parity. In conclusion, differences in the metabolic state of heifers and cows during early gestation under field conditions could not be related to their offspring’s development and glucose homeostasis.
An Updated View of Giant Molecular Clouds, Gas Flows and Star Formation in M51 with PAWS
- S. E. Meidt, E. Schinnerer, A. Hughes, D. Colombo, J. Pety, S. Garcia-Burillo, A. Leroy, C. L. Dobbs, K. F. Schuster, C. Kramer, G. Dumas, T. Thompson
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- Journal:
- Proceedings of the International Astronomical Union / Volume 8 / Issue S292 / August 2012
- Published online by Cambridge University Press:
- 21 March 2013, pp. 139-142
- Print publication:
- August 2012
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We present an overview of the latest results from the PdBI Arcsecond Whirlpool Survey (PAWS, PI: E. Schinnerer), which has mapped CO(1-0) emission in the nearby grand-design spiral galaxy M51 at 40pc resolution. Our data are sensitive to GMCs above 105 M⊙, allowing the construction of the largest GMC catalog to date – containing over 1500 objects – using the CPROPS algorithm (Rosolowsky & Leroy 2006). In the inner disk of M51, the properties of the CO emission show significant variation that can be linked to the dynamical environment in which the molecular gas is located. We find that dynamically distinct regions host clouds with different properties and exhibit different GMC mass spectra, as well as distinct patterns of star formation. To understand how this sensitivity to environment emerges, we consider the role of pressure on GMC stabilization (including shear and star formation feedback-driven turbulence). We suggest that, in the presence of significant external pressure, streaming motions driven by the spiral arm can act to reduce the surface pressure on clouds. The resulting stabilization impacts the global pattern of star formation and can account for the observed non-monotonic radial dependence of the gas depletion time. Our findings have implications for the observed scatter in the standard GMC relations and extragalactic star formation laws.
Resistance and 1/f noise between circular contacts on conductive thin films
- C. Liang, L. K.J. Vandamme, G. Leroy, J. Gest
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- Journal:
- The European Physical Journal - Applied Physics / Volume 53 / Issue 3 / March 2011
- Published online by Cambridge University Press:
- 22 February 2011, 30301
- Print publication:
- March 2011
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There is a need to characterize the quality of contacts and the noise properties of new materials deposited or grown as thin films. Poor contacts are interface dominated. Perfect contacts have a negligible interface contribution and there is only a resistance and noise contribution from outside the contact region. The presence of current crowding enhances the resistance and noise contribution. Such contacts are called constriction dominated contacts. The conductive film is characterized by its sheet resistance and normalized conductance fluctuations for a unit surface. The resistance and noise is studied between two circular top electrodes of the same diameter on the conductive. To distinguish between perfect and poor contacts and to characterize the thin film in case of good contacts, we need a set of contacts with different diameters. Models for perfect and poor contacts are investigated. The scaling of resistance and noise with contact radius r is for interface dominated poor contacts: Ri$\propto$ 1/r2 and SRi$\propto$ 1/r6. In contrast, perfect contacts with contact diameter (2r) much smaller than the distance between the centers (2b) show: Rc$\propto$ ln(b/r) and SRc$\propto$ 1/r2. From the resistance and noise measurements between constriction dominated perfect contacts, the sheet resistance and normalized noise of the thin film are calculated.
Collaboration between Civilian and Military Healthcare Professionals: A Better Way for Planning, Preparing, and Responding to All Hazard Domestic Events
- LeRoy A. Marklund, Adrienne M. Graham, Patricia G. Morton, Charles G. Hurst, Ivette Motola, Donald W. Robinson, Vivian A. Kelley, Kimberly J. Elenberg, Michael F. Russler, Daniel E. Boehm, Jr, Dawn M. Higgins, Patrick E. McAndrew, Hope M. Williamson, Rodney D. Atwood, Kermit D. Huebner, Angel A. Brotons, Geoffrey T. Miller, Laukton Y. Rimpel, Larry L. Harris, Manuel Santiago, LeRoy Cantrell
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- Journal:
- Prehospital and Disaster Medicine / Volume 25 / Issue 5 / October 2010
- Published online by Cambridge University Press:
- 28 June 2012, pp. 399-412
- Print publication:
- October 2010
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Collaboration is used by the US National Security Council as a means to integrate inter-federal government agencies during planning and execution of common goals towards unified, national security. The concept of collaboration has benefits in the healthcare system by building trust, sharing resources, and reducing costs. The current terrorist threats have made collaborative medical training between military and civilian agencies crucial.
This review summarizes the long and rich history of collaboration between civilians and the military in various countries and provides support for the continuation and improvement of collaborative efforts. Through collaboration, advances in the treatment of injuries have been realized, deaths have been reduced, and significant strides in the betterment of the Emergency Medical System have been achieved. This review promotes collaborative medical training between military and civilian medical professionals and provides recommendations for the future based on medical collaboration.
Contributors
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- By Rose Teteki Abbey, K. C. Abraham, David Tuesday Adamo, LeRoy H. Aden, Efrain Agosto, Victor Aguilan, Gillian T. W. Ahlgren, Charanjit Kaur AjitSingh, Dorothy B E A Akoto, Giuseppe Alberigo, Daniel E. Albrecht, Ruth Albrecht, Daniel O. Aleshire, Urs Altermatt, Anand Amaladass, Michael Amaladoss, James N. Amanze, Lesley G. Anderson, Thomas C. Anderson, Victor Anderson, Hope S. Antone, María Pilar Aquino, Paula Arai, Victorio Araya Guillén, S. Wesley Ariarajah, Ellen T. Armour, Brett Gregory Armstrong, Atsuhiro Asano, Naim Stifan Ateek, Mahmoud Ayoub, John Alembillah Azumah, Mercedes L. García Bachmann, Irena Backus, J. Wayne Baker, Mieke Bal, Lewis V. Baldwin, William Barbieri, António Barbosa da Silva, David Basinger, Bolaji Olukemi Bateye, Oswald Bayer, Daniel H. Bays, Rosalie Beck, Nancy Elizabeth Bedford, Guy-Thomas Bedouelle, Chorbishop Seely Beggiani, Wolfgang Behringer, Christopher M. Bellitto, Byard Bennett, Harold V. Bennett, Teresa Berger, Miguel A. Bernad, Henley Bernard, Alan E. Bernstein, Jon L. Berquist, Johannes Beutler, Ana María Bidegain, Matthew P. Binkewicz, Jennifer Bird, Joseph Blenkinsopp, Dmytro Bondarenko, Paulo Bonfatti, Riet en Pim Bons-Storm, Jessica A. Boon, Marcus J. Borg, Mark Bosco, Peter C. Bouteneff, François Bovon, William D. Bowman, Paul S. Boyer, David Brakke, Richard E. Brantley, Marcus Braybrooke, Ian Breward, Ênio José da Costa Brito, Jewel Spears Brooker, Johannes Brosseder, Nicholas Canfield Read Brown, Robert F. Brown, Pamela K. Brubaker, Walter Brueggemann, Bishop Colin O. Buchanan, Stanley M. Burgess, Amy Nelson Burnett, J. Patout Burns, David B. Burrell, David Buttrick, James P. Byrd, Lavinia Byrne, Gerado Caetano, Marcos Caldas, Alkiviadis Calivas, William J. Callahan, Salvatore Calomino, Euan K. Cameron, William S. Campbell, Marcelo Ayres Camurça, Daniel F. Caner, Paul E. Capetz, Carlos F. Cardoza-Orlandi, Patrick W. Carey, Barbara Carvill, Hal Cauthron, Subhadra Mitra Channa, Mark D. Chapman, James H. Charlesworth, Kenneth R. Chase, Chen Zemin, Luciano Chianeque, Philip Chia Phin Yin, Francisca H. Chimhanda, Daniel Chiquete, John T. Chirban, Soobin Choi, Robert Choquette, Mita Choudhury, Gerald Christianson, John Chryssavgis, Sejong Chun, Esther Chung-Kim, Charles M. A. Clark, Elizabeth A. Clark, Sathianathan Clarke, Fred Cloud, John B. Cobb, W. Owen Cole, John A Coleman, John J. Collins, Sylvia Collins-Mayo, Paul K. Conkin, Beth A. Conklin, Sean Connolly, Demetrios J. Constantelos, Michael A. Conway, Paula M. Cooey, Austin Cooper, Michael L. Cooper-White, Pamela Cooper-White, L. William Countryman, Sérgio Coutinho, Pamela Couture, Shannon Craigo-Snell, James L. Crenshaw, David Crowner, Humberto Horacio Cucchetti, Lawrence S. Cunningham, Elizabeth Mason Currier, Emmanuel Cutrone, Mary L. Daniel, David D. Daniels, Robert Darden, Rolf Darge, Isaiah Dau, Jeffry C. Davis, Jane Dawson, Valentin Dedji, John W. de Gruchy, Paul DeHart, Wendy J. Deichmann Edwards, Miguel A. De La Torre, George E. Demacopoulos, Thomas de Mayo, Leah DeVun, Beatriz de Vasconcellos Dias, Dennis C. Dickerson, John M. Dillon, Luis Miguel Donatello, Igor Dorfmann-Lazarev, Susanna Drake, Jonathan A. Draper, N. Dreher Martin, Otto Dreydoppel, Angelyn Dries, A. J. Droge, Francis X. D'Sa, Marilyn Dunn, Nicole Wilkinson Duran, Rifaat Ebied, Mark J. Edwards, William H. Edwards, Leonard H. Ehrlich, Nancy L. Eiesland, Martin Elbel, J. Harold Ellens, Stephen Ellingson, Marvin M. Ellison, Robert Ellsberg, Jean Bethke Elshtain, Eldon Jay Epp, Peter C. Erb, Tassilo Erhardt, Maria Erling, Noel Leo Erskine, Gillian R. Evans, Virginia Fabella, Michael A. Fahey, Edward Farley, Margaret A. Farley, Wendy Farley, Robert Fastiggi, Seena Fazel, Duncan S. Ferguson, Helwar Figueroa, Paul Corby Finney, Kyriaki Karidoyanes FitzGerald, Thomas E. FitzGerald, John R. Fitzmier, Marie Therese Flanagan, Sabina Flanagan, Claude Flipo, Ronald B. Flowers, Carole Fontaine, David Ford, Mary Ford, Stephanie A. Ford, Jim Forest, William Franke, Robert M. Franklin, Ruth Franzén, Edward H. Friedman, Samuel Frouisou, Lorelei F. Fuchs, Jojo M. Fung, Inger Furseth, Richard R. Gaillardetz, Brandon Gallaher, China Galland, Mark Galli, Ismael García, Tharscisse Gatwa, Jean-Marie Gaudeul, Luis María Gavilanes del Castillo, Pavel L. Gavrilyuk, Volney P. Gay, Metropolitan Athanasios Geevargis, Kondothra M. George, Mary Gerhart, Simon Gikandi, Maurice Gilbert, Michael J. Gillgannon, Verónica Giménez Beliveau, Terryl Givens, Beth Glazier-McDonald, Philip Gleason, Menghun Goh, Brian Golding, Bishop Hilario M. Gomez, Michelle A. Gonzalez, Donald K. Gorrell, Roy Gottfried, Tamara Grdzelidze, Joel B. Green, Niels Henrik Gregersen, Cristina Grenholm, Herbert Griffiths, Eric W. Gritsch, Erich S. Gruen, Christoffer H. Grundmann, Paul H. Gundani, Jon P. Gunnemann, Petre Guran, Vidar L. Haanes, Jeremiah M. Hackett, Getatchew Haile, Douglas John Hall, Nicholas Hammond, Daphne Hampson, Jehu J. Hanciles, Barry Hankins, Jennifer Haraguchi, Stanley S. Harakas, Anthony John Harding, Conrad L. Harkins, J. William Harmless, Marjory Harper, Amir Harrak, Joel F. Harrington, Mark W. Harris, Susan Ashbrook Harvey, Van A. Harvey, R. Chris Hassel, Jione Havea, Daniel Hawk, Diana L. Hayes, Leslie Hayes, Priscilla Hayner, S. Mark Heim, Simo Heininen, Richard P. Heitzenrater, Eila Helander, David Hempton, Scott H. Hendrix, Jan-Olav Henriksen, Gina Hens-Piazza, Carter Heyward, Nicholas J. Higham, David Hilliard, Norman A. Hjelm, Peter C. Hodgson, Arthur Holder, M. Jan Holton, Dwight N. Hopkins, Ronnie Po-chia Hsia, Po-Ho Huang, James Hudnut-Beumler, Jennifer S. Hughes, Leonard M. Hummel, Mary E. Hunt, Laennec Hurbon, Mark Hutchinson, Susan E. Hylen, Mary Beth Ingham, H. Larry Ingle, Dale T. Irvin, Jon Isaak, Paul John Isaak, Ada María Isasi-Díaz, Hans Raun Iversen, Margaret C. Jacob, Arthur James, Maria Jansdotter-Samuelsson, David Jasper, Werner G. Jeanrond, Renée Jeffery, David Lyle Jeffrey, Theodore W. Jennings, David H. Jensen, Robin Margaret Jensen, David Jobling, Dale A. Johnson, Elizabeth A. Johnson, Maxwell E. Johnson, Sarah Johnson, Mark D. Johnston, F. Stanley Jones, James William Jones, John R. Jones, Alissa Jones Nelson, Inge Jonsson, Jan Joosten, Elizabeth Judd, Mulambya Peggy Kabonde, Robert Kaggwa, Sylvester Kahakwa, Isaac Kalimi, Ogbu U. Kalu, Eunice Kamaara, Wayne C. Kannaday, Musimbi Kanyoro, Veli-Matti Kärkkäinen, Frank Kaufmann, Léon Nguapitshi Kayongo, Richard Kearney, Alice A. Keefe, Ralph Keen, Catherine Keller, Anthony J. Kelly, Karen Kennelly, Kathi Lynn Kern, Fergus Kerr, Edward Kessler, George Kilcourse, Heup Young Kim, Kim Sung-Hae, Kim Yong-Bock, Kim Yung Suk, Richard King, Thomas M. King, Robert M. Kingdon, Ross Kinsler, Hans G. Kippenberg, Cheryl A. 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Yee, Viktor Yelensky, Yeo Khiok-Khng, Gustav K. K. Yeung, Angela Yiu, Amos Yong, Yong Ting Jin, You Bin, Youhanna Nessim Youssef, Eliana Yunes, Robert Michael Zaller, Valarie H. Ziegler, Barbara Brown Zikmund, Joyce Ann Zimmerman, Aurora Zlotnik, Zhuo Xinping
- Edited by Daniel Patte, Vanderbilt University, Tennessee
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- The Cambridge Dictionary of Christianity
- Published online:
- 05 August 2012
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- 20 September 2010, pp xi-xliv
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The consequences of metabolic changes in high-yielding dairy cows on oocyte and embryo quality*
- J. L. M. R. Leroy, A. Van Soom, G. Opsomer, P. E. J. Bols
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Unsatisfactory reproductive performance in dairy cows, such as reduced conception rates, in addition to an increased incidence of early embryonic mortality, is reported worldwide and has been associated with a period of negative energy balance (NEB) early post partum. Typically, NEB is associated with biochemical changes such as high non-esterified fatty acid (NEFA), high β-hydroxybutyrate (β-OHB) and low glucose concentrations. The concentrations of these and other metabolites in the follicular fluid (FF) of high-yielding dairy cows during NEB were determined and extensively analyzed, and then were replicated in in vitro maturation models to investigate their effect on oocyte quality. The results showed that typical metabolic changes during NEB are well reflected in the FF of the dominant follicle. However, the oocyte seems to be relatively isolated from extremely elevated NEFA or very low glucose concentrations in the blood. Nevertheless, the in vitro maturation models revealed that NEB-associated high NEFA and low glucose levels in the FF are indeed toxic to the oocyte, resulting in deficient oocyte maturation and developmental competence. Induced apoptosis and necrosis in the cumulus cells was particularly obvious. Furthermore, maturation in saturated free fatty acid-rich media had a carry-over effect on embryo quality, leading to reduced cryotolerance of day 7 embryos. Only β-OHB showed an additive toxic effect in moderately hypoglycemic maturation conditions. These in vitro maturation models, based on in vivo observations, suggest that a period of NEB may hamper the fertility of high-yielding dairy cows through increased NEFA and decreased glucose concentrations in the FF directly affecting oocyte quality. In addition to oocyte quality, these results also demonstrate that embryo quality is reduced following an NEB episode. This important observation may be linked to the typical diet provided to stimulate milk yield, or to physiological adaptations sustaining the high milk production. Research into this phenomenon is ongoing.
Early results from the SAGE-SMC Spitzer legacy
- Karl D. Gordon, M. Meixner, R. D. Blum, W. Reach, B. A. Whitney, J. Harris, R. Indebetouw, A. D. Bolatto, J.-P. Bernard, M. Sewilo, B. L. Babler, M. Block, C. Bot, S. Bracker, L. Carlson, E. Churchwell, G. C. Clayton, M. Cohen, C. W. Engelbracht, Y. Fukui, V. Gorjian, S. Hony, J. L. Hora, F. Israel, A. Kawamura, A. K. Leroy, A. Li, S. Madden, A. R. Marble, F. Markwick-Kemper, M. Meade, K. A. Misselt, A. Mizuno, N. Mizuno, E. Muller, J. M. Oliveira, K. Olsen, T. Onishi, R. Paladini, D. Paradis, S. Points, T. Robitaille, D. Rubin, K. M. Sandstrom, S. Sato, H. Shibai, J. D. Simon, L. J. Smith, S. Srinivasan, A. G. G. M. Tielens, U. P. Vijh, S. van Dyk, J. Th. van Loon, K. Volk, D. Zaritsky
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- Journal:
- Proceedings of the International Astronomical Union / Volume 4 / Issue S256 / July 2008
- Published online by Cambridge University Press:
- 01 July 2008, pp. 184-188
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- July 2008
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Early results from the SAGE-SMC (Surveying the Agents of Galaxy Evolution in the tidally-disrupted, low-metallicity Small Magellanic Cloud) Spitzer legacy program are presented. These early results concentrate on the SAGE-SMC MIPS observations of the SMC Tail region. This region is the high H i column density portion of the Magellanic Bridge adjacent to the SMC Wing. We detect infrared dust emission and measure the gas-to-dust ratio in the SMC Tail and find it similar to that of the SMC Body. In addition, we find two embedded cluster regions that are resolved into multiple sources at all MIPS wavelengths.