903 research outputs found
Low temperature superlattice in monoclinic PZT
TEM has shown that the strongly piezoelectric material Pb(Zr0.52Ti0.48)O3
separates into two phases at low temperatures. The majority phase is the
monoclinic phase previously found by x-ray diffraction. The minority phase,
with a nanoscale coherence length, is a slightly distorted variant of the first
resulting from the anti-phase rotation of the oxygen octahedra about [111].
This work clears up a recent controversy about the origin of superlattice peaks
in these materials, and supports recent theoretical results predicting the
coexistence of ferroelectric and rotational instabilities.Comment: REVTeX4, 4 eps figures embedded. JPG version of figs. 2&4 is also
include
Modeling of association effects in mixtures of carboxylic acids with associating and non-associating components
http://apps.isiknowledge.com/full_record.do?product=UA&search_mode=GeneralSearch&qid=6&SID=V21Di6PajaHLPoM3@AJ&page=1&doc=1&colname=WOSThe group contribution with association equation of state GCA-EOS has been applied to calculate thermodynamic properties of
pure compounds and mixtures of carboxylic acids with paraffins, alcohols, water and gases, at low and high pressures. Two associating groups, OH and COOH, were defined. Self- and cross-association in
these mixtures were quantified through two parallel COOH/COOH and OH/OH associations. The validity of this approach is supported by an excellent representation of pure compound properties (vapor pressures and compressibility factors) and phase equilibria in mixtures of (associating + inert) and (associating + associating) components at low and high pressures
The extended gca-eos model for mixtures of fatty oils and derivatives
The Group Contribution Equation of State GC-EOS has been satisfactory applied
to the modeling of high-pressure phase equilibria of supercritical gases (CO2, propane, ethane, dimethylether) with pure triglycerides and natural vegetable oils. The GC-EOS model size-related parameter, i.e. the critical hard sphere diameter, of the high molecular weight compounds were determined by fitting infinite dilution activity coefficients of n-alkanes
in these heavy compounds. In this way the GC-EOS model was able to correlate
and predict vapor-liquid (VLE) and liquid-liquid (LLE) equilibria of these mixtures, using a unique set of parameters, in good agreement with experimental data. In this work the application of the model is extended to mixtures containing fatty oil derivatives, such as fatty acids, fatty acids esters, mono - and diglycerides. The associating effects between molecules are described using an upgraded version of the model, the Group Contribution Associating - EOS. Satisfactory correlation and prediction of experimental VLE, LLE and ginfinite data in binary and ternary mixtures of these products with supercritical gases are
obtained
Angular momentum effects in weak gravitational fields
It is shown that, contrary to what is normally expected, it is possible to
have angular momentum effects on the geometry of space time at the laboratory
scale, much bigger than the purely Newtonian effects. This is due to the fact
that the ratio between the angular momentum of a body and its mass, expressed
as a length, is easily greater than the mass itself, again expressed as a
length.Comment: LATEX, 8 page
Intraventricular liponeurocytoma: The role of surgery and adjuvant therapy
Background: After a series of case reports, in the WHO classification of 2007, liponeurocytomas were reclassified as grade II tumors and confirmed in the last WHO classification of 2016. We describe a rare case of intraventricular location of liponeurocytoma with review of the literature and propose the management of these rare lesions. Methods: We reviewed the pertinent english literature and extracted 9 articles to discuss 12 cases of intraventricular liponeurocytoma. We reported demographics and clinical data cases including our case. Results: Patients mean age is 37years. There is a male prevalence. All 12 patients underwent surgical treatment. A total tumor resection was obtained in 66,6%. There is one mortality reported due to intraventricular hemorrhage. In 4 cases K67/MIB-1 resulted 3% after subtotal removal. Keywords: Liponeurocytoma, Fourth ventricle, Ki-67 index, Neurocytom
Incorporation of an Interprofessional Palliative Care-Ethics Experience Into a Required Critical Care Acting Internship.
Introduction: The literature documents inadequate palliative medicine training in undergraduate and graduate medical education. As the population lives longer, many people will experience multiple chronic illnesses and the associated symptom burden. All physicians involved in clinical care of patients need to be equipped with the knowledge, attitudes, and skills necessary to provide palliative care, yet most physicians do not feel adequately prepared. We designed a curriculum to provide a meaningful palliative care-ethics (PCE) clinical experience to prepare senior medical students for future practice regardless of specialty choice.
Methods: The Zucker School of Medicine at Hofstra/Northwell integrated a PCE experience into the required 4-week acting internship in critical care (AICC). Students met weekly with an interprofessional faculty member and presented clinical cases focusing on communication and/or bioethical challenges. Faculty facilitators ensured that the presentations integrated discussion of communication skills. During the final session, students shared written reflections. Students were invited to complete a satisfaction survey postrotation and 1 year after graduation.
Results: The curriculum was evaluated positively by the graduating classes of 2015 (
Discussion: It is feasible to incorporate an interprofessional PCE experience into a required AICC. Students indicated a better understanding of palliative care and, at 1 year postgraduation, reported feeling comfortable caring for patients with serious illness
Découverte de vertébrés aquatiques présumés paléocènes dans les Andes septentrionales de Bolivie (Rio Suches, synclinorium de Putina)
Parmi les vertébrés aquatiques nouvellement découverts au nord du lac Titicaca (Bolivie) sont reconnus le téléostéen #Brychaetus$ et un crocodile dyrosauridé, fournissant la présomption d'un âge paléocène de la formation fossilifère. L'interprétation structurale de cette donnée chronologique est discutée (Résumé d'auteur
Moving forward in GME reform: a 4 + 1 model of resident ambulatory training
Traditional ambulatory training models have limitations in important domains, including opportunities for residents to learn, fragmentation of care delivery experience, and satisfaction with ambulatory experiences. New models of ambulatory training are needed. To compare the impact of a traditional ambulatory training model with a templated 4 + 1 model. A large university-based internal medicine residency using three different training sites: a patient-centered medical home, a hospital-based ambulatory clinic, and community private practices. Residents, faculty, and administrative staff. Development of a templated 4 + 1 model of residency where trainees do not attend to inpatient and outpatient responsibilities simultaneously. A mixed-methods analysis of survey and nominal group data measuring three primary outcomes: 1) Perception of learning opportunities and quality of faculty teaching; 2) Reported fragmentation of care delivery experience; 3) Satisfaction with ambulatory experiences. Self-reported empanelment was a secondary outcome. Residents\u27 learning opportunities increased (p = 0.007) but quality of faculty teaching was unchanged. Participants reported less fragmentation in the care residents provide patients in the inpatient and outpatient setting (p \u3c 0.0001). Satisfaction with ambulatory training improved (p \u3c 0.0001). Self-reported empanelment also increased (p \u3c 0.0001). Results held true for residents, faculty, and staff at all three ambulatory training sites (p \u3c 0.0001). A 4 + 1 model increased resident time in ambulatory continuity clinic, enhanced learning opportunities, reduced fragmentation of care residents provide, and improved satisfaction with ambulatory experiences. More studies of similar models are needed to evaluate effects on additional trainee and patient outcomes. (C) Society of General Internal Medicine 201
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