769 research outputs found
Octonic Electrodynamics
In this paper we present eight-component values "octons", generating
associative noncommutative algebra. It is shown that the electromagnetic field
in a vacuum can be described by a generalized octonic equation, which leads
both to the wave equations for potentials and fields and to the system of
Maxwell's equations. The octonic algebra allows one to perform compact combined
calculations simultaneously with scalars, vectors, pseudoscalars and
pseudovectors. Examples of such calculations are demonstrated by deriving the
relations for energy, momentum and Lorentz invariants of the electromagnetic
field. The generalized octonic equation for electromagnetic field in a matter
is formulated.Comment: 12 pages, 1 figur
GINA - A Polarized Neutron Reflectometer at the Budapest Neutron Centre
The setup, capabilities and operation parameters of the neutron reflectometer
GINA, the recently installed "Grazing Incidence Neutron Apparatus" at the
Budapest Neutron Centre, are introduced. GINA, a dance-floor-type,
constant-energy, angle-dispersive reflectometer is equipped with a 2D
position-sensitive detector to study specular and off-specular scattering.
Wavelength options between 3.2 and 5.7 {\AA} are available for unpolarized and
polarized neutrons. Spin polarization and analysis are achieved by magnetized
transmission supermirrors and radio-frequency adiabatic spin flippers. As a
result of vertical focusing by the five-element (pyrolytic graphite)
monochromator the reflected intensity from a 20x20 mm sample has doubled. GINA
is dedicated to studies of magnetic films and heterostructures, but unpolarized
options for non-magnetic films, membranes and other surfaces are also provided.
Shortly after its startup, reflectivity values as low as 3x10-5 have been
measured on the instrument. The facility is now open for the international user
community, but its development is continuing mainly to establish new sample
environment options, the spin analysis of off-specularly scattered radiation
and further decrease of the background
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Forward and backward recall: Different visuospatial processes when you know whatâs coming
In an immediate memory task, when participants are asked to recall list items in reverse order, benchmark memory phenomena found with more typical forward recall are not consistently reproduced. These inconsistencies have been attributed to the greater involvement of visuospatial representations in backward than in forward recall at the point of retrieval. In the present study, we tested this hypothesis with a dual-task paradigm in which manual-spatial tapping and dynamic visual noise were used as the interfering tasks. The interference task was performed during list presentation or at recall. In the first four experiments, recall direction was only communicated at the point of recall. In Experiments 1 and 2, fewer words were recalled with manual tapping than in the control condition. However, the detrimental effect of manual tapping did not vary as a function of recall direction or processing stage. In Experiment 3, dynamic visual noise did not influence recall performance. In Experiment 4, articulatory suppression was performed on all trials and manual tapping was added on half of them. As in the first two experiments, manual tapping disputed forward and backward recall to the same extent. In Experiment 5, recall direction was known before list presentation. As predicted by the visuospatial hypothesis, when manual tapping was performed during recall, its detrimental effect was limited to backward recall. Overall, results can be explained by calling upon a modified version of the visuospatial hypothesis
The first joint ESGAR/ ESPR consensus statement on the technical performance of cross-sectional small bowel and colonic imaging
Objectives: To develop guidelines describing a standardised approach to patient preparation and acquisition protocols for magnetic resonance imaging (MRI), computed tomography (CT) and ultrasound (US) of the small bowel and colon, with an emphasis on imaging inflammatory bowel disease. Methods: An expert consensus committee of 13 members from the European Society of Gastrointestinal and Abdominal Radiology (ESGAR) and European Society of Paediatric Radiology (ESPR) undertook a six-stage modified Delphi process, including a detailed literature review, to create a series of consensus statements concerning patient preparation, imaging hardware and image acquisition protocols. Results: One hundred and fifty-seven statements were scored for agreement by the panel of which 129 statements (82 %) achieved immediate consensus with a further 19 (12 %) achieving consensus after appropriate modification. Nine (6 %) statements were rejected as consensus could not be reached. Conclusions: These expert consensus recommendations can be used to help guide cross-sectional radiological practice for imaging the small bowel and colon. Key points: âą Cross-sectional imaging is increasingly used to evaluate the bowel âą Image quality is paramount to achieving high diagnostic accuracy âą Guidelines concerning patient preparation and image acquisition protocols are provided
Person-Centred Therapists Call on SCoPEd Partners to Offer PSA-Backed Membership Home for those Opposed to Framework
A group of prominent practitioners, writers, trainers and academics from the Person-Centred community in the UK, along with two organisations, have published an open letter calling on the SCoPEd organisations to provide a professional home on their PSA-backed registers for members who do not wish to be aligned with SCoPEdâs divisive and hierarchical framework
Les dĂ©bats entre Ătat, Ăglise catholique et Ăglises rĂ©formĂ©es autour de lâĂ©dit de tolĂ©rance de 1787
Un siĂšcle aprĂšs lâĂ©dit de Fontainebleau de 1685 qui rĂ©voque lâĂ©dit de Nantes, et Ă la suite de nombreux dĂ©bats, Louis XVI accorde en novembre 1787 aux non-catholiques du royaume, protestants et juifs, un Ă©dit que lâon appelle couramment lâĂ©dit de tolĂ©rance ou lâĂ©dit de Breteuil, du nom du secrĂ©taire dâĂtat qui a participĂ© Ă sa rĂ©daction. Ce texte ne donne en aucune façon une quelconque libertĂ© de culte aux non-catholiques, mais uniquement un Ă©tat civil. En effet, dĂ©sormais, ils peuvent faire enregistrer les naissances, mariages et dĂ©cĂšs de leurs communautĂ©s, rĂ©habiliter les unions illĂ©gales contractĂ©es avant lâĂ©dit et faire lĂ©gitimer les enfants nĂ©s de ces unions auprĂšs dâun juge ou dâun curĂ©, ce dernier nâayant aucun rĂŽle religieux mais devenant seulement un officier dâĂ©tat civil .
Depuis la fin du XVIIe siĂšcle, les protestants français, car ce sont principalement eux qui sont concernĂ©s par cette loi, refusent la plupart du temps de faire cĂ©lĂ©brer leur union par un curĂ©, se contentant de la signature dâun contrat notariĂ© et de la bĂ©nĂ©diction Ă©ventuelle dâun pasteur du DĂ©sert, comme ils renoncent Ă©galement Ă faire baptiser les enfants nĂ©s de ces unions et Ă demander une sĂ©pulture au curĂ© dans le cimetiĂšre catholique ; ces comportements, variables selon les provinces, se trouvent confortĂ©es par le synode national du DĂ©sert de 1744 qui exhorte les rĂ©formĂ©s Ă nâaccepter aucune compromission avec la confession adverse . Ainsi, tout au long du siĂšcle des LumiĂšres, une partie de la population française vit sans Ă©tat civil. Ce ne sont pas les mesures rĂ©pressives prises contre les rĂ©formĂ©s, que ce soit les nombreuses lois, les enfermements, les enlĂšvements dâenfants, les procĂšs contre les cadavres ou les campagnes de rebaptisations des enfants rĂ©formĂ©s, sur le modĂšle des dragonnades des annĂ©es 1680, qui changent la situation .
Ă partir du milieu du XVIIIe siĂšcle un dĂ©bat tripartite sâinstaure entre lâĂtat, les Ăglises rĂ©formĂ©es et lâĂglise catholique, chacun avec ses propositions, avant mĂȘme lâaffaire Calas qui Ă©clate en 1761, et les nĂ©gociations aboutissent Ă un accord en 1787 entre lâĂtat et les Ăglises rĂ©formĂ©es, contre lâavis de lâĂglise catholique. Lâobjectif de cette communication est dâune part dâessayer de comprendre lâĂ©volution de la position de lâĂtat Ă lâĂ©gard des protestants, alors que les persĂ©cutions sont nombreuses jusquâau dĂ©but des annĂ©es 1760, mais aussi dâĂ©tudier les arguments des trois partenaires pour obtenir une solution en sâintĂ©ressant Ă des Ă©crits publiĂ©s durant cette pĂ©riode , principalement des pamphlets et des mĂ©moires. Je mâappuierai pour comprendre les trois points de vue sur un texte publiĂ© anonymement en 1788 et intitulĂ© ConfĂ©rence entre le frĂšre Pancrace, Capucin, le docteur Hoth-Man, ministre protestant, & M. Robino, avocat au Parlement de Paris
Observer agreement for small bowel ultrasound in Crohn's disease: results from the METRIC trial
PURPOSE: To prospectively evaluate interobserver agreement for small bowel ultrasound (SBUS) in newly diagnosed and relapsing Crohn's disease. METHODS: A subset of patients recruited to a prospective trial comparing the diagnostic accuracy of MR enterography and SBUS underwent a second SBUS performed by one of a pool of six practitioners, who recorded the presence, activity and location of small bowel and colonic disease. Detailed segmental mural and extra-mural observations were also scored. Interobserver variability was expressed as percentage agreement with a construct reference standard, split by patient cohort, grouping disease as present or absent. Prevalence adjusted bias adjusted kappa (PABAK), and simple percentage agreement between practitioners, irrespective of the reference standard, were calculated. RESULTS: Thirty-eight patients (11 new diagnosis, 27 relapse) were recruited from two sites. Overall percentage agreement for small bowel disease presence against the consensus reference was 82% (52-95% (95%CI)), kappa coefficient (Îș) 0.64, (substantial agreement) for new diagnosis and 81%, Îș 0.63 (substantial agreement) for the relapsing cohort. Agreement for colonic disease presence was 64%, Îș 0.27 (fair agreement) in new diagnosis and 78%,Îș 0.56 (moderate agreement) in the relapsing cohort. Simple agreement between practitioners was 84% and 87% for small bowel and colonic disease presence respectively. Practitioners agreed on small bowel disease activity in 24/27 (89%) where both identified disease. Kappa agreement for detailed mural observations ranged from Îș 0.00 to 1.00. CONCLUSION: There is substantial practitioner agreement for small bowel disease presence in newly diagnosed and relapsing CD patients, supporting wider dissemination of enteric US
IntAct:intra-operative fluorescence angiography to prevent anastomotic leak in rectal cancer surgery: a randomized controlled trial
Aim
Anastomotic leak (AL) is a major complication of rectal cancer surgery. Despite advances in surgical practice, the rates of AL have remained static, at around 10â15%. The aetiology of AL is multifactorial, but one of the most crucial risk factors, which is mostly under the control of the surgeon, is blood supply to the anastomosis. The MRC/NIHR IntAct study will determine whether assessment of anastomotic perfusion using a fluorescent dye (indocyanine green) and nearâinfrared laparoscopy can minimize the rate of AL leak compared with conventional whiteâlight laparoscopy. Two mechanistic subâstudies will explore the role of the rectal microbiome in AL and the predictive value of CT angiography/perfusion studies.
Method
IntAct is a prospective, unblinded, parallelâgroup, multicentre, European, randomized controlled trial comparing surgery with intraâoperative fluorescence angiography (IFA) against standard care (surgery with no IFA). The primary endâpoint is rate of clinical AL at 90 days following surgery. Secondary endâpoints include all AL (clinical and radiological), change in planned anastomosis, complications and reâinterventions, use of stoma, costâeffectiveness of the intervention and quality of life. Patients should have a diagnosis of adenocarcinoma of the rectum suitable for potentially curative surgery by anterior resection. Over 3 years, 880 patients from 25 European centres will be recruited and followed up for 90 days.
Discussion
IntAct will rigorously evaluate the use of IFA in rectal cancer surgery and explore the role of the microbiome in AL and the predictive value of preoperative CT angiography/perfusion scanning
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