24 research outputs found
Roots and (re)sources of value (in)definiteness versus contextuality. A contribution to the Pitowsky Volume in memory of Itamar Pitowsky (1950--2010)
In Itamar Pitowsky's reading of the Gleason and the Kochen-Specker theorems,
in particular, his Logical Indeterminacy Principle, the emphasis is on the
value indefiniteness of observables which are not within the preparation
context. This is in stark contrast to the prevalent term {\em contextuality}
used by many researchers in informal, heuristic yet omni-realistic and
potentially misleading ways. This paper discusses both concepts and argues in
favor of value indefiniteness in all but a continuum of contexts intertwining
in the vector representing a single pure (prepared) state. Even more
restrictively, and inspired by operationalism but not justified by Pitowsky's
Logical Indeterminacy Principle or similar, one could identify with a "quantum
state" a single quantum context -- aka the respective maximal observable, or,
in terms of its spectral decomposition, the associated orthonormal basis - from
the continuum of intertwining context, as per the associated maximal observable
actually or implicitly measured.Comment: 11 pages, revised and polished, discussion on joint probabilities of
observables in different contexts adde
Significance testing as perverse probabilistic reasoning
Truth claims in the medical literature rely heavily on statistical significance testing. Unfortunately, most physicians misunderstand the underlying probabilistic logic of significance tests and consequently often misinterpret their results. This near-universal misunderstanding is highlighted by means of a simple quiz which we administered to 246 physicians at two major academic hospitals, on which the proportion of incorrect responses exceeded 90%. A solid understanding of the fundamental concepts of probability theory is becoming essential to the rational interpretation of medical information. This essay provides a technically sound review of these concepts that is accessible to a medical audience. We also briefly review the debate in the cognitive sciences regarding physicians' aptitude for probabilistic inference
Estudo epidemiolĂłgico das fraturas mandibulares em hospital pĂșblico da cidade de SĂŁo Paulo
OBJETIVO: Analisar a frequĂȘncia epidemiolĂłgica de fraturas mandibulares correlacionando gĂȘnero, faixa etĂĄria, fatores etiolĂłgicos, localização anatĂŽmica, e tipos de traços de fratura. MĂTODOS: Estudo retrospectivo nos prontuĂĄrios de 883 pacientes portadores de fraturas faciais, atendidos no Pronto Socorro do Hospital Geral de Vila Penteado, pelo Serviço de Cirurgia e Traumatologia Buco Maxilo Facial (SĂŁo Paulo - Brasil), num perĂodo de trĂȘs anos (janeiro de 2004 a dezembro de 2006). RESULTADOS: Dos 883 pacientes avaliados, 270 apresentaram fraturas mandibulares (30,5 %). O gĂȘnero masculino foi o mais acometido (76,7%) na faixa etĂĄria de 20 a 29 anos (33,0%), o fator etiolĂłgico de maior freqĂŒĂȘncia foi acidente com veĂculos automotores (35,2%), o corpo da mandĂbula foi a localização anatĂŽmica mais atingida (47,4%) e os traços Ășnicos prevaleceram (76,7%). CONCLUSĂO: As fraturas, em sua maioria, foram simples (traço Ășnico), localizadas em corpo mandibular, e destacadas no sexo masculino, na faixa etĂĄria de 20 a 29 anos, alĂ©m do que o fator etiolĂłgico mais comum foi acidente com veĂculos automotores
Fratura de mandĂbula: anĂĄlise de 293 pacientes tratados no Hospital de ClĂnicas da Universidade Federal de UberlĂąndia Mandibular fracture: analysis of 293 patients treated in the Hospital of Clinics, Federal University of UberlĂąndia
A fratura de mandĂbula ocupa o segundo lugar entre as fraturas dos ossos da face, tendo havido aumento significativo de casos nos Ășltimos anos. A nĂŁo-identificação e o tratamento inadequado podem levar Ă deformidade estĂ©tica ou funcional permanente. OBJETIVO: Avaliar os casos submetidos Ă redução de fratura de mandĂbula no Hospital de ClĂnicas da Universidade Federal de UberlĂąndia, entre janeiro de 1974 e dezembro de 2002. FORMA DE ESTUDO: coorte historica. PACIENTES E MĂTODO: Duzentos e noventa e trĂȘs pacientes foram submetidos Ă redução de fratura de mandĂbula e retrospectivamente foram avaliados segundo fatores relacionados a: paciente, trauma, quadro clĂnico e tratamento cirĂșrgico. RESULTADOS: Houve uma clara tendĂȘncia de aumento do nĂșmero de fraturas de mandĂbula ao longo dos anos. Houve um predomĂnio no sexo masculino (4:1), com pico de ocorrĂȘncia entre 20 a 29 anos. As principais causas de fratura da mandĂbula neste estudo foram acidentes de trĂąnsito e violĂȘncia, perfazendo juntas 72,4%. Cento e trinta e cinco pacientes apresentavam fratura Ășnica. Os sĂtios mais acometidos foram, em ordem decrescente, sĂnfise, cĂŽndilo, Ăąngulo, corpo, ramo e processo coronĂłide. Foram realizadas redução incruenta (28), cruenta (213) e associação das duas (11 pacientes), sendo que 56,8% dos pacientes foram tratados nos primeiros 3 dias e 50,4% recebeu a alta hospitalar atĂ© o primeiro pĂłs-operatĂłrio. Cerca de 10% dos pacientes apresentaram complicaçÔes, sendo osteomielite a mais freqĂŒente. CONCLUSĂO: A incidĂȘncia de fraturas de mandĂbula foi marcadamente maior no sexo masculino, durante a terceira dĂ©cada de vida. A causa mais comum foi o acidente de trĂąnsito e as regiĂ”es mais atingidas foram sĂnfise e cĂŽndilo. As fraturas isoladas de mandĂbula ocorreram em mais de metade dos casos. A maioria dos pacientes foi tratada nos primeiros trĂȘs dias e recebeu alta atĂ© o primeiro pĂłs-operatĂłrio. A redução cruenta foi tratamento mais comumente empregado. A complicação mais freqĂŒente foi a osteomielite.<br>Mandibular fracture is the second most common facial fracture and there has been a significant increase in number of cases in the last years. Misidentification and inadequate treatment can take to permanent aesthetic or functional deformity. AIM: Evaluate cases of mandibular fracture reduction in the Hospital of Clinics of the Federal University of UberlĂąndia, from January of 1974 to December of 2002. STUDY DESIGN: historical cohort. PATIENT AND METHOD: Two hundred and ninety-three cases of reduction of mandibular fractures were retrospectively analyzed according to factors related to: patient, trauma, signs and symptoms, and surgical treatment. RESULTS: There has been a clear tendency of increase of the number of mandibular fractures along the years. There was higher prevalence in male (4:1), with occurrence peak between 20 to 29 years old. The principal causes of fracture in this study were traffic accidents and violence, representing 72.4%. One hundred and thirty-five patients presented only one fracture. The most injured sites were, in decreasing order, symphysis, condyle, angle, body, ramus, and coronoid. We performed closed reduction (28), open reduction (213) and association of the two (11 patients); 56.8% of the patients were treated within the first 3 days; and, 50.4% were discharged from the hospital until the first postoperative day. About 10% of the patients presented complications, being osteomyelitis the most frequent one. CONCLUSION: The incidence of mandibular fractures was remarkably larger in the male sex, during the third decade of life. The most common cause was traffic accident, and symphysis and condyle were the most injured sites. Isolated fractures occurred in over half of the cases. Most of the patients were treated in the first three days and were discharged until the first postoperative visit. Closed reduction was the treatment most commonly employed. The most frequent complication was osteomyelitis
Mandibular fractures: a comparative analysis between young and adult patients in the southeast region of Turkey
OBJECTIVE: The purpose of this study was to review and compare the differences between mandibular fractures in young and adult patients. MATERIAL AND METHODS: Patients treated at the Oral and Maxillofacial Department of Dicle University during a five-year period between 2000 and 2005 were retrospectively evaluated with respect to age groups, gender, etiology, localization and type of fractures, treatment methods and complications. RESULTS: 532 patients were included in the study, 370 (70%) males and 162 (30%) females, with a total of 744 mandibular fractures. The mean age of young patients was 10, with a male-female ratio of 2:1. The mean age of adult patients was 28, with a male-female ratio of 3:1. The most common causes of injury were falls (65%) in young patients and traffic accidents (38%) in adults. The most common fracture sites were the symphysis (35%) and condyle (36%) in young patients, and the symphysis in adults (36%). Mandibular fractures were generally treated by arch bar and maxillomandibular fixation in both young (67%) and adult (39%) patients, and 43% of the adult patients were treated by open reduction and internal fixation. CONCLUSION: There was a similar gender, monthly and type of treatment distribution in both young and adult patients in the southeast region of Turkey. However, there were differences regarding age, etiology and fracture site. These findings between young and adult patients are broadly similar to those from other studies. Analysis of small differences may be an important factor in assessing educational and socioeconomic environments