485 research outputs found
Aeroacoustic Measurements of the Bell 699 Rotor on the Tiltrotor Test Rig in the National Full-Scale Aerodynamics Complex 40- by 80-Foot Wind Tunnel
The Tiltrotor Test Rig (TTR) with the Bell 699 Rotor was tested in the National Full-Scale Aerodynamics Complex (NFAC) 40- by 80-Foot Wind Tunnel from 2017 to 2018. The primary goal of the test was to understand the operational capabilities of the TTR while also acquiring research data, including acoustic data. A data quality study revealed that the NFAC 40- by 80-Foot Wind Tunnel is an adequate acoustic environment to test the Bell 699 Rotor for helicopter, conversion, and airplane configurations. Representative acoustic data are presented, and selected acoustic data and corresponding test conditions are included
Application of Resonance Perturbation Theory to Dynamics of Magnetization in Spin Systems Interacting with Local and Collective Bosonic Reservoirs
We apply our recently developed resonance perturbation theory to describe the
dynamics of magnetization in paramagnetic spin systems interacting
simultaneously with local and collective bosonic environments. We derive
explicit expressions for the evolution of the reduced density matrix elements.
This allows us to calculate explicitly the dynamics of the macroscopic
magnetization, including characteristic relaxation and dephasing time-scales.
We demonstrate that collective effects (i) do not influence the character of
the relaxation processes but merely renormalize the relaxation times, and (ii)
significantly modify the dephasing times, leading in some cases to a
complicated (time inhomogeneous) dynamics of the transverse magnetization,
governed by an effective time-dependent magnetic field
Low Dose Focused Ultrasound Induces Enhanced Tumor Accumulation of Natural Killer Cells
Natural killer (NK) cells play a vital antitumor role as part of the innate immune system. Efficacy of adoptive transfer of NK cells depends on their ability to recognize and target tumors. We investigated whether low dose focused ultrasound with microbubbles (ldbFUS) could facilitate the targeting and accumulation of NK cells in a mouse xenograft of human colorectal adenocarcinoma (carcinoembryonic antigen (CEA)-expressing LS-174T implanted in NOD.Cg-Prkdc^(scid)Il2rg^(tm1Wjl)/SzJ (NSG) mice) in the presence of an anti-CEA immunocytokine (ICK), hT84.66/M5A-IL-2 (M5A-IL-2). Human NK cells were labeled with an FDA-approved ultra-small superparamagnetic iron oxide particle, ferumoxytol. Simultaneous with the intravenous injection of microbubbles, focused ultrasound was applied to the tumor. In vivo longitudinal magnetic resonance imaging (MRI) identified enhanced accumulation of NK cells in the ensonified tumor, which was validated by endpoint histology. Significant accumulation of NK cells was observed up to 24 hrs at the tumor site when ensonified with 0.50 MPa peak acoustic pressure ldbFUS, whereas tumors treated with at 0.25 MPa showed no detectable NK cell accumulation. These clinically translatable results show that ldbFUS of the tumor mass can potentiate tumor homing of NK cells that can be evaluated non-invasively using MRI
The European Centre for Disease Prevention and Control (ECDC) pilot point prevalence survey of healthcare-associated infections and antimicrobial use
A standardised methodology for a combined point prevalence survey (PPS) on healthcare-associated infections (HAIs) and antimicrobial use in European acute care hospitals developed by the European Centre for Disease Prevention and Control was piloted across Europe. Variables were collected at national, hospital and patient level in 66 hospitals from 23 countries. A patient-based and a unit-based protocol were available. Feasibility was assessed via national and hospital questionnaires. Of 19,888 surveyed patients, 7.1% had an HAI and 34.6% were receiving at least one antimicrobial agent. Prevalence results were highest in intensive care units, with 28.1% patients with HAI, and 61.4% patients with antimicrobial use. Pneumonia and other lower respiratory tract infections (2.0% of patients; 95% confidence interval (CI): 1.8-2.2%) represented the most common type (25.7%) of HAI. Surgical prophylaxis was the indication for 17.3% of used antimicrobials and exceeded one day in 60.7% of cases. Risk factors in the patient-based protocol were provided for 98% or more of the included patients and all were independently associated with both presence of HAI and receiving an antimicrobial agent. The patient-based protocol required more work than the unit-based protocol, but allowed collecting detailed data and analysis of risk factors for HAI and antimicrobial use.peer-reviewe
Antimicrobial use in European acute care hospitals: results from the second point prevalence survey (PPS) of healthcare-associated infections and antimicrobial use, 2016 to 2017
Antimicrobial agents used to treat infections are life-saving. Overuse may result in more frequent adverse effects and emergence of multidrug-resistant microorganisms. In 2016-17, we performed the second point-prevalence survey (PPS) of healthcare-associated infections (HAIs) and antimicrobial use in European acute care hospitals. We included 1,209 hospitals and 310,755 patients in 28 of 31 European Union/European Economic Area (EU/EEA) countries. The weighted prevalence of antimicrobial use in the EU/EEA was 30.5% (95% CI: 29.2-31.9%). The most common indication for prescribing antimicrobials was treatment of a community-acquired infection, followed by treatment of HAI and surgical prophylaxis. Over half (54.2%) of antimicrobials for surgical prophylaxis were prescribed for more than 1 day. The most common infections treated by antimicrobials were respiratory tract infections and the most commonly prescribed antimicrobial agents were penicillins with beta-lactamase inhibitors. There was wide variation of patients on antimicrobials, in the selection of antimicrobial agents and in antimicrobial stewardship resources and activities across the participating countries. The results of the PPS provide detailed information on antimicrobial use in European acute care hospitals, enable comparisons between countries and hospitals, and highlight key areas for national and European action that will support efforts towards prudent use of antimicrobials
School, Community and Clinical Psychology Training and Working together in the Interdisciplinary School Mental Health Field
The Impact of Parent Empowerment in Children’s Mental Health Services on Parenting Stress
Emotional and behavioral (EB) problems in children are associated with increased perceptions of strain in parenting. Among children receiving services, parenting stress has been linked to initiating services for their children, and may strain the relationship between parent and child. In contrast, parental engagement and empowerment in services is an important quality indicator for positive treatment outcomes. However, no known studies have examined the association between parent empowerment in their child’s services and their perceptions of stress related to parenting a child with significant mental health needs. Further, no studies have explored whether empowerment moderates the relationship between the child’s symptoms and parental perceptions of stress. The current study examined the impact of child EB problems and parent empowerment on parenting stress. Among a sample of 525 parents of children receiving school-based services for disruptive behavior disorders, child EB problems significantly predicted parenting stress. Parent empowerment also correlated with lower parenting stress, as hypothesized. Although parent empowerment was not found to moderate the relationship between child symptomatology and parenting stress, the relationship between parent empowerment and parenting stress differed based on child gender and age. Parent empowerment was associated with lower parenting stress more for parents of females and younger children than for parents of males and older children
Taking nature into lab: biomineralization by heavy metal-resistant streptomycetes in soil
Biomineralization by heavy metal-resistant streptomycetes was tested to evaluate the potential influence on metal mobilities in soil. Thus, we designed an experiment adopting conditions from classical laboratory methods to natural conditions prevailing in metal-rich soils with media spiked with heavy metals, soil agar, and nutrientenriched or unamended soil incubated with the bacteria. As a result, all strains were able to form struvite minerals (MgNH4PO4 6H2O) on tryptic soy broth (TSB)-media supplemented with AlCl3, MnCl2 and CuSO4, as well as on soil agar. Some strains additionally formed struvite on nutrient-enriched contaminated and control soil, as well as on metal contaminated soil without addition of media components. In contrast, switzerite (Mn3(PO4)2 7H2O) was exclusively formed on minimal media spiked with MnCl2 by four heavy metal-resistant strains, and on nutrient-enriched control soil by one strain. Hydrated nickel hydrogen phosphate was only crystallized on complex media supplemented with NiSO4 by most strains. Thus, mineralization is a dominant property of streptomycetes, with different processes likely to occur under laboratory conditions and sub-natural to natural conditions. This new understanding might have implications for our understanding of biological metal resistance mechanisms. We assume that biogeochemical cycles, nutrient storage and metal resistance might be affected by formation and re-solubilization of minerals like struvite in soil at microscale
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