2,888 research outputs found
Resonant inelastic x-ray scattering study of charge excitations in La2CuO4
We report a resonant inelastic x-ray scattering study of the dispersion
relations of charge transfer excitations in insulating LaCuO. These
data reveal two peaks, both of which show two-dimensional characteristics. The
lowest energy excitation has a gap energy of eV at the zone center,
and a dispersion of eV. The spectral weight of this mode becomes
dramatically smaller around (, ). The second peak shows a smaller
dispersion ( eV) with a zone-center energy of eV. We argue
that these are both highly dispersive exciton modes damped by the presence of
the electron-hole continuum.Comment: 5 pages, 3 figure
Pembuatan dan Uji Efektivitas Chess Of Chemistry (Coc)sebagai Upaya Peningkatan Minat, Prestasi dan Kecepatan Berpikir Siswa dalam Pokok Bahasan Stoikiometri
Pembelajaran dibidang Kimia seringkali dianggap sulit bagi pelajar maupun mahasiswa terutama untuk bidang perhitungan kimia dan deskripsi objek yang dipelajari di kimia yang cenderung abstrak, kendala ini mesti dicari solusinya agar bidang kimia yang punya peranan penting di kehidupan dapat dipelajari dengan baik oleh pelajar ataupun mahasiswa, sehingga Sumber Daya Manusia (SDM) yang memahami kimia akan dapat termanfaatkan dengan baik demi kemajuan bangsa. Penelitian ini bertujuan untuk mengetahui pengaruh dan efektivitas Chess of Chemistry (COC) sebagai Media Pembelajaran terhadap pembelajaran siswa pada pokok bahasan Stoikiometri khususnya dan perhitungan kimia pada umumnya, penelitian ini berjenis eksperimen (Experiment Research) yang melibatkan 2 kelas yang mengambil perwakilan dari kelas-kelas IPA yang dipilih berdasarkan homogenitas sebagai sampel. Populasi dari penelitian ini adalah pelajar bidang IPA SMAN 8 Kota Bengkulu, pengujian efektivitas dari COC ini dilakukan dengan membandingkan rata-rata nilai dan kecepatan berpikir menggunakan tes yang singkat(dalam rentang waktu yang sempit), antara kelas yang menggunakan Chess of Chemistry (COC) dalam pembelajaran dan yang tidak, dengan membandingkan nilai rata-rata tes, waktu dan nilai rata-rata tes sebelumnya serta membandingkan nilai rata-rata kelas yang menggunakan COC dan kelas yang menggunakan metode konvensional, kesimpulan efektivitas positif diambil, jika nilai rata-rata kelas dengan metode menggunakan Chess of Chemistry (COC) > dari kelas yang menggunakan metode tanpa media Chess of Chemistry (COC)
The measurement of aircraft performance and stability and control after flight through natural icing conditions
The effects of airframe icing on the performance and stability and control of a twin-engine commuter-class aircraft were measured by the NASA Lewis Research Center. This work consisted of clear air tests with artificial ice shapes attached to the horizontal tail, and natural icing flight tests in measured icing clouds. The clear air tests employed static longitudinal flight test methods to determine degradation in stability margins for four simulated ice shapes. The natural icing flight tests employed a data acquisition system, which was provided under contract to NASA by Kohlman Systems Research Incorporated. This system used a performance modeling method and modified maximum likelihood estimation (MMLE) technique to determine aircraft performance degradation and stability and control. Flight test results with artificial ice shapes showed that longitudinal, stick-fixed, static margins are reduced on the order of 5 percent with flaps up. Natural icing tests with the KSR system corroborated these results and showed degradation in the elevator control derivatives on the order of 8 to 16 percent depending on wing flap configuration. Performance analyses showed the individual contributions of major airframe components to the overall degration in lift and drag
Tailoring teleportation to the quantum alphabet
We introduce a refinement of the standard continuous variable teleportation
measurement and displacement strategies. This refinement makes use of prior
knowledge about the target state and the partial information carried by the
classical channel when entanglement is non-maximal. This gives an improvement
in the output quality of the protocol. The strategies we introduce could be
used in current continuous variable teleportation experiments.Comment: 16 pages, 6 figures, RevTeX, made changes as recommended by referee,
other minor textual corrections, resubmitted to Phys. Rev.
The vertebrate fauna of the Upper Permian of Niger—III, morphology and ontogeny of the hindlimb of Moradisaurus grandis (Reptilia, Captorhinidae)
We describe hindlimb elements of the large captorhinid Moradisaurus grandis (Reptilia: Captorhinidae) recently collected from the Upper Permian Moradi Formation of north-central Niger. This description is based primarily on an associated partial skeleton comprising a hemimandible, vertebral column, and partial left and nearly complete right hindlimb. Additionally, we report on a well-preserved, articulated, and essentially complete juvenile pes that provides important information on the ontogeny of the captorhinid tarsus. The hindlimb of Moradisaurus is stout and more massively built than in any other known captorhinid. The femur displays several features interpreted as adaptations to the demands of large body size, and the tibia and fibula have short, wide shafts and hypertrophied condyles and epicondyles. The astragalus is very derived, possessing two accessory ossifications and a relatively horizontal tibial articulation, indicating that the tibia was held more vertically than in other captorhinids. The calcaneum is co-ossified with distal tarsal five. The juvenile pes indicates that the captorhinid centrale arose from the fusion of two ossification centers, and that the captorhinid astragalus arose from the fusion of at least three ossification centers
Crystal growth of ice Ih by revapor-deposition and diffusion suppression of monomolecular water in a polymer solid: spectroscopic observation of phase transition of water sorbed into solid polystyrene.
Monomolecular water in a solid polymer, which has no effective hydrogen bonding sites, was revealed by temperature-variable Fourier transform infrared spectroscopy to be condensable and crystallizable. Ice Ih formed in the polymer matrix was grown by vapor deposition and was reduced by sublimation. Moreover, rapid cooling induced crystal growth by vapor deposition during heating (revapor-deposition). These results indicate the requirement of a change in the generally accepted understanding of the thermal responses of water in a polymer matrix and give rise to a problem for general interpretation of the category of water in a polymer matrix based on calorimetrical analysis at very low water contents
Evaluating clinical utility of subgingival and salivary endotoxin activity levels as periodontal biomarkers.
OBJECTIVES: The use of periodontal biomarkers for identification and monitoring of unique patient populations could foster better stratification of at-risk groups, increase access to treatment for those most in need, facilitate preventive measures and improve personalised care plans. The aim of this study was to examine the diagnostic and prognostic utility of oral lipopolysaccharides as bacterially-derived periodontal biomarkers. METHODS: Periodontal parameters were recorded, and saliva and subgingival plaque samples were collected at the beginning of the study from periodontally healthy volunteers and periodontitis patients, and three months after completion of conventional periodontal treatment in the periodontitis group. Endotoxin activity in the samples was measured using the recombinant factor C assay. Associations between clinical periodontal parameters and subgingival and salivary endotoxin activities were analysed using a multivariate regression model, while the ROC curve was applied to estimate the sensitivity, specificity and c-statistics for salivary and subgingival endotoxin activities as diagnostic biomarkers for periodontitis. RESULTS: Significant correlations were found between subgingival endotoxin activities, probing pocket depth and periodontal diagnosis, which were independent from patients' age, gender and smoking status. In addition, subgingival endotoxin levels had high specificity and sensitivity in detecting periodontal health and disease (0.91 and 0.85 respectively). Salivary endotoxin activity was positively associated with periodontal diagnosis, mean probing pocket depth, percentages of sites over 4 mm and full mouth bleeding score. However, it was inferior in discriminating patients with stable periodontium from those with periodontitis (sensitivity = 0.69, specificity = 0.61) compared to subgingival endotoxin activity. CONCLUSIONS: Subgingival endotoxin activity has good diagnostic and prognostic values as a site-specific periodontal biomarker and is not influenced by the patient's age, gender or smoking status. In contrast, salivary endotoxin activity, as a patient-level biomarker, is dependent on patient's age, has poorer diagnostic and prognostic capability, but shows good correlations with disease susceptibility and both its extent and severity
Demographic and psychological predictors of community pharmacists’ cancer-related conversations with patients: a cross-sectional analysis and survey study
BACKGROUND:
There is increasing interest in the role of community pharmacy in the early diagnosis and prevention of cancer. This study set out to examine how often community pharmacists (CPs) encourage patients to spot or respond to potential signs and symptoms of cancer, and how often they help people to make an informed decision about taking part in bowel cancer screening.
METHODS:
Data from 400 UK CPs, who completed the 2018 Cancer Research UK Healthcare Professional Tracker survey, were analysed. The primary outcomes were: ‘how often CPs encourage patients to spot or respond to potential signs and symptoms of cancer’ and ‘how often CPs encourage eligible people to make an informed decision to participate in bowel cancer screening’. Associations between behaviours and demographic and psychological variables (Capability, Opportunity and Motivation) were assessed using multivariate logistic regression.
RESULTS:
Most (n = 331, 82.8%) CPs reported occasionally, frequently or always encouraging patients to spot or respond to potential signs and symptoms of cancer, while only half (n = 203, 50.8%) reported occasionally, frequently or always helping people make an informed decision to participate in bowel cancer screening. Female sex (aOR: 3.20, 95%CI: 1.51, 6.81; p < 0.01) and increased Opportunity (aOR: 1.72, 95%CIs: 1.12, 2.64; p < 0.05) and Motivation (aOR: 1.76, 95%CIs: 1.37, 2.27; p < 0.001) were associated with encouraging patients to spot or respond to potential signs and symptoms of cancer; all three psychological variables were associated with helping people to make an informed decision to participate in bowel cancer screening (Capability: aOR: 1.39, 95%CIs: 1.26, 1.52, p < 0.001; Opportunity: aOR: 1.44, 95%CIs: 1.11, 1.87; p < 0.01; Motivation: aOR: 1.45, 95%CIs: 1.05, 2.00; p < 0.05).
CONCLUSIONS:
Most CPs encourage patients to spot or respond to potential cancer symptoms, while only half help them make an informed decision to participate in bowel cancer screening. A multifaceted approach, targeting multiple COM-B components, is required to change these behaviours
Toward the use of temporary tattoo electrodes for impedancemetric respiration monitoring and other electrophysiological recordings on skin
The development of dry, ultra-conformable and unperceivable temporary tattoo electrodes (TTEs), based on the ink-jet printing of poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) on top of commercially available temporary tattoo paper, has gained increasing attention as a new and promising technology for electrophysiological recordings on skin. In this work, we present a TTEs epidermal sensor for real time monitoring of respiration through transthoracic impedance measurements, exploiting a new design, based on the application of soft screen printed Ag ink and magnetic interlink, that guarantees a repositionable, long-term stable and robust interconnection of TTEs with external “docking” devices. The efficiency of the TTE and the proposed interconnection strategy under stretching (up to 10%) and over time (up to 96 h) has been verified on a dedicated experimental setup and on humans, fulfilling the proposed specific application of transthoracic impedance measurements. The proposed approach makes this technology suitable for large-scale production and suitable not only for the specific use case presented, but also for real time monitoring of different bio-electric signals, as demonstrated through specific proof of concept demonstrators
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