337 research outputs found
Critical slowing down near the multiferroic phase transition in MnWO
By using broadband dielectric spectroscopy in the radiofrequency and
microwave range we studied the magnetoelectric dynamics in the multiferroic
chiral antiferromagnet MnWO. Above the multiferroic phase transition at
K we observe a critical slowing down of the corresponding
magnetoelectric fluctuations resembling the soft-mode behavior in canonical
ferroelectrics. This electric field driven excitation carries much less
spectral weight than ordinary phonon modes. Also the critical slowing down of
this mode scales with an exponent larger than one which is expected for
magnetic second order phase transition scenarios. Therefore the investigated
dynamics have to be interpreted as the softening of an electrically active
magnetic excitation, an electromagnon.Comment: 5 pages, 4 figures, appendi
Remote terminal system evaluation
An Earth Resources Data Processing System was developed to evaluate the system for training, technology transfer, and data processing. In addition to the five sites included in this project two other sites were connected to the system under separate agreements. The experience of these two sites is discussed. The results of the remote terminal project are documented in seven reports: one from each of the five project sites, Purdue University, and an overview report summarizing the other six reports
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Low-level waste feed staging plan
The `Preliminary Low-Level Waste Feed Staging Plan` was updated to reflect the latest requirement in the Tank Waste Remediation Privatization Request for Proposals (RFP) and amendments. The updated plan develops the sequence and transfer schedule for retrieval of DST supernate by the management and integration contractor and delivery of the staged supernate to the private low-activity waste contractors for treatment. Two DSTs are allocated as intermediate staging tanks. A transfer system conflict analysis provides part of the basis for determining transfer system upgrade requirements to support both low-activity and high-level waste feed delivery. The intermediate staging tank architecture and retrieval system equipment are provided as a planning basis until design requirements documents are prepared. The actions needed to successfully implement the plan are identified. These include resolution of safety issues and changes to the feed envelope limits, minimum order quantities, and desired batch sizes
Rapidly progressive dementia with thalamic degeneration and peculiar cortical prion protein immunoreactivity, but absence of proteinase K resistant PrP: a new disease entity?
BACKGROUND: Human prion diseases are a group of rare fatal neurodegenerative conditions with well-developed clinical and neuropathological diagnostic criteria. Recent observations have expanded the spectrum of prion diseases beyond the classically recognized forms. RESULTS: In the present study we report six patients with a novel, apparently sporadic disease characterised by thalamic degeneration and rapidly progressive dementia (duration of illness 2-12 months; age at death: 55-81 years). Light and electron microscopic immunostaining for the prion protein (PrP) revealed a peculiar intraneuritic distribution in neocortical regions. Proteinase K resistant PrP (PrPres) was undetectable by Western blotting in frontal cortex from the three cases with frozen tissue, even after enrichment for PrPres by centrifugation or by phosphotungstic acid precipitation. Conformation-dependent immunoassay analysis using a range of PK digestion conditions (and no PK digestion) produced only very limited evidence of meaningful D-N (denatured/native) values, indicative of the presence of disease-associated PrP (PrPSc) in these cases, when the results were compared with appropriate negative control groups. CONCLUSIONS: Our observation expands the spectrum of conditions associated with rapidly progressive dementia and may have implications for the understanding of the pathogenesis of prion diseases
Quasimolecular electronic structure of the spin-liquid candidate Ba3InIr2O9
The mixed-valent iridate Ba3InIr2O9 has been discussed as a promising candidate for quantum spin-liquid behavior. The compound exhibits Ir4.5+ ions in face-sharing IrO6 octahedra forming Ir2O9 dimers with three t2g holes per dimer. Our results establish Ba3InIr2O9 as a cluster Mott insulator. Strong intradimer hopping delocalizes the three t2g holes in quasimolecular dimer states while interdimer charge fluctuations are suppressed by Coulomb repulsion. The magnetism of Ba3InIr2O9 emerges from spin-orbit entangled quasimolecular moments with yet unexplored interactions, opening up a new route to unconventional magnetic properties of 5d compounds. Using single-crystal x-ray diffraction we find the monoclinic space group C2/c already at room temperature. Dielectric spectroscopy shows insulating behavior. Resonant inelastic x-ray scattering reveals a rich excitation spectrum below 1.5 eV with a sinusoidal dynamical structure factor that unambiguously demonstrates the quasimolecular character of the electronic states. Below 0.3 eV, we observe a series of excitations. According to exact diagonalization calculations, such low-energy excitations reflect the proximity of Ba3InIr2O9 to a hopping-induced phase transition based on the condensation of a quasimolecular spin-orbit exciton. The dimer ground state roughly hosts two holes in a bonding j=12 orbital and the third hole in a bonding j=32 orbital
Risk Factors for Prognosis in Patients With Severely Decreased GFR
Introduction: Patients with chronic kidney disease (CKD) and estimated glomerular filtration rate (eGFR) < 30 ml/min per 1.73 m 2 (corresponding to CKD stage G4+) comprise a minority of the overall CKD population but have the highest risk for adverse outcomes. Many CKD G4+ patients are older with multiple comorbidities, which may distort associations between risk factors and clinical outcomes. Methods: We undertook a meta-analysis of risk factors for kidney failure treated with kidney replacement therapy (KRT), cardiovascular disease (CVD) events, and death in participants with CKD G4+ from 28 cohorts (n = 185,024) across the world who were part of the CKD Prognosis Consortium. Results: In the fully adjusted meta-analysis, risk factors associated with KRT were time-varying CVD, male sex, black race, diabetes, lower eGFR, and higher albuminuria and systolic blood pressure. Age was associated with a lower risk of KRT (adjusted hazard ratio: 0.74; 95% confidence interval: 0.69–0.80) overall, and also in the subgroup of individuals younger than 65 years. The risk factors for CVD events included male sex, history of CVD, diabetes, lower eGFR, higher albuminuria, and the onset of KRT. Systolic blood pressure showed a U-shaped association with CVD events. Risk factors for mortality were similar to those for CVD events but also included smoking. Most risk factors had qualitatively consistent associations across cohorts. Conclusion: Traditional CVD risk factors are of prognostic value in individuals with an eGFR < 30 ml/min per 1.73 m 2, although the risk estimates vary for kidney and CVD outcomes. These results should encourage interventional studies on correcting risk factors in this high-risk population
Relational considerations in the use of influence tactics.
It is proposed that the existing relationship between the influencing agent and the target of influence plays a central role in the choice of using hard and soft influence tactics. In a field study, 3 key aspects of the relation between agent and target were examined. and the results generally supported our hypotheses. First, the more unfairly people felt they were treated, the more often they wielded influence, especially using harder influence tactics. Second. the better the influencing agent liked the target. the relatively less often he or she used hard tactics. Finally, the more the influencing agent felt dependent upon the target, the fewer influence tactics, both hard and soft, were used. The discussion focuses on both the practical and theoretical implications of these findings
A first assessment of the impact of the extreme 2018 summer drought on Central European forests
In 2018, Central Europe experienced one of the most severe and long-lasting summer drought and heat wave ever recorded. Before 2018, the 2003 millennial drought was often invoked as the example of a “hotter drought”, and was classified as the most severe event in Europe for the last 500 years. First insights now confirm that the 2018 drought event was climatically more extreme and had a greater impact on forest ecosystems of Austria, Germany and Switzerland than the 2003 drought. Across this region, mean growing season air temperature from April to October was more than 3.3°C above the long-term average, and 1.2°C warmer than in 2003. Here, we present a first impact assessment of the severe 2018 summer drought and heatwave on Central European forests. In response to the 2018 event, most ecologically and economically important tree species in temperate forests of Austria, Germany and Switzerland showed severe signs of drought stress. These symptoms included exceptionally low foliar water potentials crossing the threshold for xylem hydraulic failure in many species and observations of widespread leaf discoloration and premature leaf shedding. As a result of the extreme drought stress, the 2018 event caused unprecedented drought-induced tree mortality in many species throughout the region. Moreover, unexpectedly strong drought-legacy effects were detected in 2019. This implies that the physiological recovery of trees was impaired after the 2018 drought event, leaving them highly vulnerable to secondary drought impacts such as insect or fungal pathogen attacks. As a consequence, mortality of trees triggered by the 2018 events is likely to continue for several years. Our assessment indicates that many common temperate European forest tree species are more vulnerable to extreme summer drought and heat waves than previously thought. As drought and heat events are likely to occur more frequently with the progression of climate change, temperate European forests might approach the point for a substantial ecological and economic transition. Our assessment also highlights the urgent need for a pan-European ground-based monitoring network suited to track individual tree mortality, supported by remote sensing products with high spatial and temporal resolution to track, analyse and forecast these transitions
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Factors affecting the motivation of healthcare professionals providing care to Emiratis with type 2 diabetes
OBJECTIVE: We aimed to identify facilitators of and barriers to healthcare professionals' motivation in a diabetes centre in the United Arab Emirates (UAE).
DESIGN: A qualitative research approach was employed using semistructured interviews to assess perception of and attitudes regarding healthcare professionals' motivation in providing good quality diabetes care.
SETTING: A diabetes centre located in Abu-Dhabi, UAE.
PARTICIPANTS: Healthcare professionals including specialist physicians, dieticians, podiatrists, health educators and nurses were recruited through purposive sampling.
MAIN OUTCOME MEASURES: After data collection, the audiotaped interviews were transcribed verbatim and subjected to content analysis.
RESULTS: Nine semistructured interviews were conducted with healthcare professionals of various professional backgrounds. Important facilitators and barriers related to patient, professional, organization and cultural factors were identified. Barriers that related to heavy workload, disjointed care, lack of patient compliance and awareness, and cultural beliefs and attitudes about diabetes were common. Key facilitators included the patient's role in achieving therapeutic outcomes as well as compliance, cooperation and communication.
CONCLUSION: This qualitative study provides some unique insights about factors affecting healthcare professionals' motivation in providing good quality care. To improve the motivation of healthcare professionals in the management of diabetes and therefore the quality of diabetes care, several steps are needed. Importantly, the role of primary care should be reinforced and strengthened regarding the management of type 2 diabetes mellitus, privacy of the consultation time should be highly protected and regulated, and awareness of the Emirate culture and its impact on health should be disseminated to the healthcare professionals providing care to Emirates with diabetes. Also, greater emphasis should be placed on educating Emiratis with diabetes on, and involving them in, the management of their condition
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