998 resultados para Equivalente de dose individual
Resumo:
Analiza los efectos de El Niño sobre el peso total individual de la sardina y la caballa para lo cual se comparan los datos de una año normal con los obtenidos abordo del BIC
Resumo:
We consider adaptive sequential lossy coding of bounded individual sequences when the performance is measured by the sequentially accumulated mean squared distortion. Theencoder and the decoder are connected via a noiseless channel of capacity $R$ and both are assumed to have zero delay. No probabilistic assumptions are made on how the sequence to be encoded is generated. For any bounded sequence of length $n$, the distortion redundancy is defined as the normalized cumulative distortion of the sequential scheme minus the normalized cumulative distortion of the best scalarquantizer of rate $R$ which is matched to this particular sequence. We demonstrate the existence of a zero-delay sequential scheme which uses common randomization in the encoder and the decoder such that the normalized maximum distortion redundancy converges to zero at a rate $n^{-1/5}\log n$ as the length of the encoded sequence $n$ increases without bound.
Resumo:
This study was designed to explore individual and dyadic coping strategies in the aftermath of a traumatic event. Eighteen persons having experienced a physical assault or a road accident within six to twelve months before the study, and eighteen matched control persons were recruited together with their partners. Each participant and his/her partner filled in several questionnaires on individual and dyadic coping strategies, level of stress and PTSD-symptomatology. Results indicate that participants having experienced a trauma, compared to controls, report a general lack of dyadic coping and, when facing daily hassles, specific decreases in individual coping strategies. These differences are discussed in the context of marital coping processes.
Resumo:
BACKGROUND AND PURPOSE: A pregnant woman was referred for post-operative radiotherapy of a malignant schwannoma in the head and neck region. A best-treatment plan was devised in order to minimize the fetal dose. MATERIAL AND METHODS: The fetal dose resulting from radiological examinations was determined according to international protocols, that resulting from radiotherapy was calculated according to Recommendation 36 of the American Association of Physicists in Medicine (AAPM) Task Group. Pre-treatment dosimetry was performed with an anthropomorphic phantom. Several alternative treatment plans were evaluated. The use of a multileaf collimator (MLC) and a virtual wedge (VW) was compared to cerrobend blocks (CB) and physical wedge (PW). In-vivo dosimetry was performed using a vaginal probe containing thermoluminescent dosimeters (TLD). RESULTS: The total fetal dose resulting from diagnostic and radiotherapy procedures was estimated to be 36 mGy. The technique based on MLC and VW was elected for patient treatment. Measurements for this configuration resulted in afetal dose reduction of 82%. The shielding of the patient's abdomen further reduced the fetal dose by 42%. CONCLUSION: The use of VW and MLC for the treatment of a pregnant woman is highly recommended. Each case should be individually studied with pre-treatment and in-vivo dosimetry.
Resumo:
This paper shows how recently developed regression-based methods for thedecomposition of health inequality can be extended to incorporateindividual heterogeneity in the responses of health to the explanatoryvariables. We illustrate our method with an application to the CanadianNPHS of 1994. Our strategy for the estimation of heterogeneous responsesis based on the quantile regression model. The results suggest that thereis an important degree of heterogeneity in the association of health toexplanatory variables which, in turn, accounts for a substantial percentageof inequality in observed health. A particularly interesting finding isthat the marginal response of health to income is zero for healthyindividuals but positive and significant for unhealthy individuals. Theheterogeneity in the income response reduces both overall health inequalityand income related health inequality.
Resumo:
In this introductory editorial, we provide a brief overview of the history of individual difference research in leadership. We explain the major challenges that trait research faced, and why it was revived primarily because of methodological advancements. Next, we argue that leadership individual difference research is at a cusp of a renaissance. We explain why we are at this cusp and what researchers should do reify the renaissance in terms of theoretical extensions of trait models, the application of robust methodological advancements, and the development of process models linking distal (i.e., traits) predictors to proximal predictors (e.g., behaviors, skills, attitudes), and the latter to leader outcomes. We then summarize the papers we accepted for the special issue, and conclude with an optimistic note for leadership individual difference research.
Resumo:
PURPOSE: The prognostic impact of complete response (CR) achievement in multiple myeloma (MM) has been shown mostly in the context of autologous stem-cell transplantation. Other levels of response have been defined because, even with high-dose therapy, CR is a relatively rare event. The purpose of this study was to analyze the prognostic impact of very good partial response (VGPR) in patients treated with high-dose therapy. PATIENTS AND METHODS: All patients were included in the Intergroupe Francophone du Myelome 99-02 and 99-04 trials and treated with vincristine, doxorubicin, and dexamethasone (VAD) induction therapy followed by double autologous stem-cell transplantation (ASCT). Best post-ASCT response assessment was available for 802 patients. RESULTS: With a median follow-up of 67 months, median event-free survival (EFS) and 5-year EFS were 42 months and 34%, respectively, for 405 patients who achieved at least VGPR after ASCT versus 32 months and 26% in 288 patients who achieved only partial remission (P = .005). Five-year overall survival (OS) was significantly superior in patients achieving at least VGPR (74% v 61% P = .0017). In multivariate analysis, achievement of less than VGPR was an independent factor predicting shorter EFS and OS. Response to VAD had no impact on EFS and OS. The impact of VGPR achievement on EFS and OS was significant in patients with International Staging System stages 2 to 3 and for patients with poor-risk cytogenetics t(4;14) or del(17p). CONCLUSION: In the context of ASCT, achievement of at least VGPR is a simple prognostic factor that has importance in intermediate and high-risk MM and can be informative in more patients than CR.
Resumo:
The concept of authority crosses many social sciences, but there is a lack of common taxonomy and definitions on this topic. The aims of this review are: (1) to define the basic characteristics of the authority relationship, reaching a definition suitable for the different domains of social psychology and social sciences; (2) to bridge the gap between individual and societal levels of explanation concerning the authority relationship, by proposing an interpretation within the framework of social representations. The authority relationship can be conceived as a negotiation of meanings and it is closely linked to shared value orientation and the attribution of meanings negotiated within a society. We assume that the authority relationship is socially constructed and represents both a shared representation of society and a normative principle of social life. A multidisciplinary approach is adopted, crossing definitions and studies provided in sociology, political science, law and social psychology.
Resumo:
Second cancer risk assessment for radiotherapy is controversial due to the large uncertainties of the dose-response relationship. This could be improved by a better assessment of the peripheral doses to healthy organs in future epidemiological studies. In this framework, we developed a simple Monte Carlo (MC) model of the Siemens Primus 6 MV linac for both open and wedged fields that we then validated with dose profiles measured in a water tank up to 30 cm from the central axis. The differences between the measured and calculated doses were comparable to other more complex MC models and never exceeded 50%. We then compared our simple MC model with the peripheral dose profiles of five different linacs with different collimation systems. We found that the peripheral dose between two linacs could differ up to a factor of 9 for small fields (5 × 5 cm(2)) and up to a factor of 10 for wedged fields. Considering that an uncertainty of 50% in dose estimation could be acceptable in the context of risk assessment, the MC model can be used as a generic model for large open fields (≥10 × 10 cm(2)) only. The uncertainties in peripheral doses should be considered in future epidemiological studies when designing the width of the dose bins to stratify the risk as a function of the dose.
Resumo:
Aquest treball fa un repàs a les diferents teories relacionades amb el camp d’estudi de les estratègies d’aprenentatge de segones llengües i respon a preguntes de recerca relacionades amb la freqüència d’ús de les estratègies i la relació amb les diferències individuals. La primera part és una introducció on s’hi plantegen les preguntes de recerca en les quals es basa el treball. La segona part, consisteix en un resum de les teories relacionades amb el tema de les estratègies d’estudi de segones llengües, i una posada en comú d’aquestes per mostrar les dificultats que hi ha per trobar consens en quant a la identificació i classificació de les estratègies. La tercera part, presenta la metodologia utilitzada per a la recollida de dades per tal de contestar les preguntes de recerca. En la quarta part es desenvolupa la recerca duta a terme; i finalment es presenten les conclusions extretes de cada pregunta de recerca plantejada.
Resumo:
Iowa Individual Income Tax Statistical Report 2007
Resumo:
Objective The aim is to analyze and compare individual BMI growth patterns of adults from Switzerland and the U.S. Methods The analyses are based on data from two population representative longitudinal household surveys, one from Switzerland, the other from the U.S. Each data set contains up to four data points for each adult individual. We use multilevel models for growth. Results It can be shown that growth patterns are different in different cohorts in the two countries: there are only small growth differences in the youngest and oldest, but large differences in the middle ages. The individual BMI increase of the middle age Swiss amounts to only half of that in the comparable U.S. individuals. Conclusion Given the much higher BMI level especially in the youngest cohort, this points to severe obesity problems in the U.S. middle aged population in the near future. A positive correlation between individual BMI level and growth may aggravate this fact.
Resumo:
Els alumnes elaboren produccions de qualitat superior quan treballen en parelles que quan ho fan individualment. Sota aquesta màxima, l’estudi demostra que quan els alumnes escriuen textos científics descriptius, justificatius i descriptius-justificatius en parella milloren aspectes relacionats amb determinades habilitats inherents a qualsevol tipus de text, com l’estructuració de la informació i l’adequació del llenguatge al context, i d’altres específiques de textos descriptius i justificatius. És sorprenent constatar que aquesta millora es dóna en tot tipus d’alumnes, tant aquells amb hàbits d’estudi superiors com aquells amb dificultats d’aprenentatge, i que els avantatges d’aquesta metodologia de treball no es circumscriuen tan sols a l’àmbit acadèmic; els alumnes prefereixen treballar en parella perquè els permet compartir punts de vista i ajudar-se mútuament. Per tant, els resultats demostren que complementar les classes de ciències amb el treball en parella possibilita assolir amb més garanties l’aprenentatge significatiu dels nostres alumnes.
Resumo:
The effective dose delivered to the patient was determined, by modeling, for 257 types of examinations covering the different modalities of diagnostic and interventional radiology. The basic operational dosimetric quantities considered were obtained from the parameters of the examinations on the basis of dosimetric models. These models required a precise characterization of each examination. The operational dosimetric quantities were converted into doses to organs and effective doses using appropriate conversion factors. The determination of the collective effective dose to the Swiss population requires a number of corrections to account for the variability of several parameters: sensitivity of the detection system, age, gender, and build of the patient. The use of various dosimetric models is illustrated in this paper for a limited number of examination types covering the different radiological modalities, for which the established typical effective doses are given. With regard to individual doses, the study indicated that the average effective doses per type of examination can be classified into three levels: (a) the weakly irradiating examinations (less than 0.1 mSv), which represent 78% of the examinations and 4% of the collective dose, (b) the moderately irradiating examinations (between 0.1 mSv and 10 mSv), which represent 21% of the examinations and 72% of the collective dose, (c) the strongly irradiating examinations (more than 10 mSv), which represent 1% of the examinations and 24% of the collective dose.