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Observational constraints on atmospheric and oceanic cross-equatorial heat transports: revisiting the precipitation asymmetry problem in climate models
Satellite based top-of-atmosphere (TOA) and surface radiation budget observations are combined with mass corrected vertically integrated atmospheric energy divergence and tendency from reanalysis to infer the regional distribution of the TOA, atmospheric and surface energy budget terms over the globe. Hemispheric contrasts in the energy budget terms are used to determine the radiative and combined sensible and latent heat contributions to the cross-equatorial heat transports in the atmosphere (AHT_EQ) and ocean (OHT_EQ). The contrast in net atmospheric radiation implies an AHT_EQ from the northern hemisphere (NH) to the southern hemisphere (SH) (0.75 PW), while the hemispheric difference in sensible and latent heat implies an AHT_EQ in the opposite direction (0.51 PW), resulting in a net NH to SH AHT_EQ (0.24 PW). At the surface, the hemispheric contrast in the radiative component (0.95 PW) dominates, implying a 0.44 PW SH to NH OHT_EQ. Coupled model intercomparison project phase 5 (CMIP5) models with excessive net downward surface radiation and surface-to-atmosphere sensible and latent heat transport in the SH relative to the NH exhibit anomalous northward AHT_EQ and overestimate SH tropical precipitation. The hemispheric bias in net surface radiative flux is due to too much longwave surface radiative cooling in the NH tropics in both clear and all-sky conditions and excessive shortwave surface radiation in the SH subtropics and extratropics due to an underestimation in reflection by clouds
Exoplanets and SETI
The discovery of exoplanets has both focused and expanded the search for
extraterrestrial intelligence. The consideration of Earth as an exoplanet, the
knowledge of the orbital parameters of individual exoplanets, and our new
understanding of the prevalence of exoplanets throughout the galaxy have all
altered the search strategies of communication SETI efforts, by inspiring new
"Schelling points" (i.e. optimal search strategies for beacons). Future efforts
to characterize individual planets photometrically and spectroscopically, with
imaging and via transit, will also allow for searches for a variety of
technosignatures on their surfaces, in their atmospheres, and in orbit around
them. In the near-term, searches for new planetary systems might even turn up
free-floating megastructures.Comment: 9 page invited review. v2 adds some references and v3 has other minor
additions and modification
Role of supplemental foods and habitat structural complexity in persistence and coexistence of generalist predatory mites
Variation in the strength of intraguild predation (IGP) may be related to habitat structural complexity and to additional resources outside the narrow predator-prey relationship. We studied the food web interactions on grape, which involves two generalist predatory mites. We evaluated the effects of grape powdery mildew (GPM) as supplemental food, and habitat structural complexity provided by domatia. Our findings suggest that structural and nutritional diversity/complexity promote predatory mite abundance and can help to maintain the beneficial mites - plants association. The effect of these factors on coexistence between predators is influenced by the supplemental food quality and relative differences in body size of interacting species
A cluster randomized controlled trial of a clinical pathway for hospital treatment of heart failure: study design and population
<p>Abstract</p> <p>Background</p> <p>The hospital treatment of heart failure frequently does not follow published guidelines, potentially contributing to the high morbidity, mortality and economic cost of this disorder. Consequently the development of clinical pathways has the potential to reduce the current variability in care, enhance guideline adherence, and improve outcomes for patients. Despite enthusiasm and diffusion, the widespread acceptance of clinical pathways remain questionable because very little prospective controlled data demonstrated their effectiveness. The Experimental Prospective Study on the Effectiveness and Efficiency of the Implementation of Clinical Pathways was designed in order to conduct a rigorous evaluation of clinical pathways in hospital treatment of acute heart failure. The primary objective of the trial was to evaluate the effectiveness of the implementation of clinical pathways for hospital treatment of heart failure in Italian hospitals.</p> <p>Methods/design</p> <p>Two-arm, cluster-randomized trial. 14 community hospitals were randomized either to arm 1 (clinical pathway: appropriate use of practice guidelines and supplies of drugs and ancillary services, new organization and procedures, patient education, etc.) or to arm 2 (no intervention, usual care). 424 patients sample (212 in each group), 80% of power at the 5% significance level (two-sided). The primary outcome measure is in-hospital mortality. We will also analyze the impact of the clinical pathways comparing the length and the appropriateness of the stay, the rate of unscheduled readmissions, the customers' satisfaction and the costs treating the patients with the pathways and with the current practice along all the observation period. The quality of the care will be assessed by monitoring the use of diagnostic and therapeutic procedures during hospital stay and by measuring key quality indicators at discharge.</p> <p>Discussion</p> <p>This paper examines the design of the evaluation of a complex intervention. Since clinical pathways are made up of various interconnecting parts we have chosen the cluster-randomized controlled trial because is widely accepted as the most reliable method of determining effectiveness when measuring cost-effectiveness in real practice.</p> <p>Trial Registration</p> <p>ClinicalTrials.gov ID [NCT00519038]</p
Remote Electrical Stimulation by Means of Implanted Rectifiers
Miniaturization of active implantable medical devices is currently compromised by the available means for electrically powering them. Most common energy supply techniques for implants β batteries and inductive couplers β comprise bulky parts which, in most cases, are significantly larger than the circuitry they feed. Here, for overcoming such miniaturization bottleneck in the case of implants for electrical stimulation, it is proposed to make those implants act as rectifiers of high frequency bursts supplied by remote electrodes. In this way, low frequency currents will be generated locally around the implant and these low frequency currents will perform stimulation of excitable tissues whereas the high frequency currents will cause only innocuous heating. The present study numerically demonstrates that low frequency currents capable of stimulation can be produced by a miniature device behaving as a diode when high frequency currents, neither capable of thermal damage nor of stimulation, flow through the tissue where the device is implanted. Moreover, experimental evidence is provided by an in vivo proof of concept model consisting of an anesthetized earthworm in which a commercial diode was implanted. With currently available microelectronic techniques, very thin stimulation capsules (diameter <500 Β΅m) deliverable by injection are easily conceivable
Inferring stabilizing mutations from protein phylogenies : application to influenza hemagglutinin
One selection pressure shaping sequence evolution is the requirement that a protein fold with sufficient stability to perform its biological functions. We present a conceptual framework that explains how this requirement causes the probability that a particular amino acid mutation is fixed during evolution to depend on its effect on protein stability. We mathematically formalize this framework to develop a Bayesian approach for inferring the stability effects of individual mutations from homologous protein sequences of known phylogeny. This approach is able to predict published experimentally measured mutational stability effects (ΞΞG values) with an accuracy that exceeds both a state-of-the-art physicochemical modeling program and the sequence-based consensus approach. As a further test, we use our phylogenetic inference approach to predict stabilizing mutations to influenza hemagglutinin. We introduce these mutations into a temperature-sensitive influenza virus with a defect in its hemagglutinin gene and experimentally demonstrate that some of the mutations allow the virus to grow at higher temperatures. Our work therefore describes a powerful new approach for predicting stabilizing mutations that can be successfully applied even to large, complex proteins such as hemagglutinin. This approach also makes a mathematical link between phylogenetics and experimentally measurable protein properties, potentially paving the way for more accurate analyses of molecular evolution
Unusual association of alveolar rhabdomyosarcoma with pancreatic metastasis: emerging role of PET-CT in tumor staging
Pancreatic metastases in childhood cancer have been rarely reported in the radiology literature although ample evidence exists in pathology reports for its occurrence in patients with alveolar rhabdomyosarcomas (RMS).
Assess the occurrence of pancreatic metastases in alveolar rhabdomyosarcomas, increase awareness of this association and reassess current staging protocols.
Three major oncology centers reviewed their records and imaging examinations. Patientsβ history and demographics, primary tumor site and histology, presence of tumor recurrence, and presence and location of other metastases were reviewed.
Pancreatic metastases occurred in eight patients with alveolar RMS. Four of these presented at diagnosis and four with disease recurrence. In recurrent disease, the duration between the diagnosis of the primary tumor and pancreatic metastases varied from 8Β months to 6Β years (meanβΒ±βSD: 2.38βΒ±β2.49Β years). In all patients who received PET scans, pancreatic metastases showed a marked FDG-uptake, but had variable detectability with CT. Pancreatic metastases were not associated with certain primary tumor locations or presence of other metastases, mandating an evaluation of the pancreas in all cases of alveolar rhabdomyosarcomas.
Radiologists should be sensitized and actively evaluate the pancreas in patients with alveolar RMS. Optimizing CT and PET-CT protocols may increase the diagnostic yield
Immunogenicity and Cross-Reactivity of 2009β2010 Inactivated Seasonal Influenza Vaccine in US Adults and Elderly
The campaign of 2009β2010 Northern Hemisphere seasonal vaccination was concurrent with the 2009 H1N1 pandemic. Using a hemagglutination inhibition (HAI) assay, we evaluated the immunogenicity and cross-reactivity of 2009β2010 inactivated trivalent influenza vaccine (TIV) in US adult and elderly populations. Vaccination of TIV resulted in a robust boost on the antibody response of all subjects to seasonal A/Brisbane/59/2007 (H1N1) and A/Uruguay/716/2007 (H3N2) with over 70% of recipients reaching a seroprotective titer of 40. B/Brisbane/60/2008 was the least immunogenic among the three seasonal vaccine strains with <30% of TIV recipients reaching a seroprotective titer of 40. TIV vaccination also induced a moderate boost on the pandemic specific antibody responses. Twenty-four percent of adults and 36% of elderly reached a seroprotective HAI titer of 40 or more against pandemic A/South Carolina/18/2009 (H1N1) after receiving TIV compared to 4% and 7% at the beginning of vaccination, respectively. In addition, 22% of adults and 34% of elderly showed an increase of 4-fold or more in A/South Carolina/18/2009 specific HAI titers after TIV vaccination. The pandemic specific cross-reactive antibodies strongly correlated with the post-vaccination HAI titers against the seasonal H3N2 vaccine strain in all subjects
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