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Distinct Models (distinct + models)

Distribution by Scientific Domains

Medical Sciences	33%
Business, Economics, Finance and Accounting	33%

Selected Abstracts

Decision Makers as Statisticians: Diversity, Ambiguity, and Learning

ECONOMETRICA, Issue 5 2009
Nabil I. Al-Najjar
I study individuals who use frequentist models to draw uniform inferences from independent and identically distributed data. The main contribution of this paper is to show that distinct models may be consistent with empirical evidence, even in the limit when data increases without bound. Decision makers may then hold different beliefs and interpret their environment differently even though they know each other's model and base their inferences on the same evidence. The behavior modeled here is that of rational individuals confronting an environment in which learning is hard, rather than individuals beset by cognitive limitations or behavioral biases. [source]

Analysis and selection criteria of BSIM4 flicker noise simulation models

INTERNATIONAL JOURNAL OF CIRCUIT THEORY AND APPLICATIONS, Issue 7 2008
T. Noulis
Abstract CMOS transistors' noise performance is mainly dominated by flicker (1/f) noise. BSIM4.X MOSFET simulation model develops two distinct models, SPICE-Flicker and BSIM-Flicker, to calculate flicker noise. In this paper, these two models are analytically examined and compared to noise measurements, using an NMOS and a PMOS device fabricated in 0.6µm process by Austria Mikro Systeme (AMS). MOSFET 1/f noise measurements and the respective simulations were obtained under various bias conditions, as to study which flicker noise model is the optimum in each operating region. Measurement temperature was constant at 295,K. Comparisons suggest that in an NMOS transistor operating in the triode or saturation region, BSIM-Flicker model is accurate and therefore preferable. In a PMOS transistor, the most suitable model to describe its 1/f noise performance in the linear regime is also BSIM-Flicker, whereas SPICE-Flicker is more preferable in saturation. In NMOS transistors, the selected model provides a great accurate description of flicker noise, contrary to PMOS transistors, where simulation models appear to be quite unreliable and need further improvement. Copyright © 2007 John Wiley & Sons, Ltd. [source]

Relationship between legitimation, competition and organizational death: current state of the art

INTERNATIONAL JOURNAL OF MANAGEMENT REVIEWS, Issue 1 2004
Manuel Núñez Nickel
There is agreement among ecology researchers that the concepts of legitimation and competition are partly responsible for organizational selection. Finding adequate measures to represent these concepts, however, has been elusive and has been the main obstacle to the development of this stream of investigation. On the basis of the germinal density dependence model, we identify two lines of research, which have generated seven distinct models. This survey shows that there has been a general tendency to use only three variables to measure legitimation and competition, which are often measured together. However, we argue that fruitful results have emerged when efforts have been made to separate both concepts and that there is some potential in using new measures (mass or concentration) which have so far only found limited application in the field of population demography. These findings, together with the inconclusive results of this stream of research, allow us to identify the existing gaps in the literature and comment on directions for future research. [source]

Stem cell therapy of the liver, Fusion or fiction?

LIVER TRANSPLANTATION, Issue 4 2004
Marc H. Dahlke
Various stem cell populations have been described in distinct models of liver regeneration. This review provides an overview of these different stem cell populations aimed at unifying diverse views of liver stem cell biology. Embryonic stem cells, hemopoietic stem cells, mesenchymal stem cells, liver-derived hepatic stem cells, bone marrow,derived hepatic stem cells, and mature hepatocytes (as cells with stemlike properties) are considered separately. In so doing, we seek to clarify the nomenclature of putative liver stem cell types. Experiments that address the question of cellular fusion versus transdifferentiation as explanations for observed liver regeneration are highlighted. This review concludes with a series of open questions that should be addressed in the context of clinical liver disease before attempts at human therapeutic interventions. (Liver Transpl 2004;10:471,479.) [source]

Prevalence and etiology of acquired anemia in Medieval York, England

AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 2 2005
Amy Sullivan
Abstract This paper presents three distinct models for the development of acquired anemia: iron-deficiency anemia produced by the inadequate intake and/or absorption of iron, the anemia of chronic disease (ACD) caused by the body's natural iron-withholding defense against microbial invaders, and megaloblastic anemia caused by insufficient intake and/or absorption of vitamin B12 or folic acid. These etiological models are used to interpret the distribution and etiology of anemia among adult individuals interred at the Medieval Gilbertine Priory of St. Andrew, Fishergate, York (n = 147). This bioarchaeological analysis uncovered not only a strong relationship between decreasing status and increasing prevalence of anemia for both men and women, but also identified clear sex-based differences at this site. Within the high-status group, blood and iron loss as a result of rampant parasitism likely produced an environment ripe for the development of iron-deficiency anemia, while the parasitic consumption of vitamin B12 may have caused occasional cases of megaloblastic anemia. As status decreases, the interpretation of anemia becomes more complex, with megaloblastic anemia and ACD emerging as viable, potentially heavy contributors to the anemia experiences of low-status people at St. Andrew's. Apart from status effects, women (especially young women) are disproportionately affected by anemia when compared to men within their own status group and, on average, are also more likely to have experienced anemia than their male peers from other status groups. This suggests that high iron-demand reproductive functions helped to make iron-deficiency anemia a chronic condition in many women's lives irrespective of their status affiliation. Am J Phys Anthropol, 2005. © 2005 Wiley-Liss, Inc. [source]

Consequential Apoptosis in the Cerebellum Following Injury to the Developing Rat Forebrain

BRAIN PATHOLOGY, Issue 3 2006
Deanna L. Taylor
In focal brain lesions, alterations in blood flow and cerebral metabolism can be detected in brain areas remote from the primary injury. The cellular consequences of this phenomenon, originally termed diaschisis, are not fully understood. Here, we report that in two distinct models of forebrain injury, neuronal death in the cerebellum, a site distant to the primary injury, results as consequence of neuronal loss in the forebrain. Fourteen-day-old rats were subjected to unilateral forebrain injury, achieved by either hypoxia-ischemia (right carotid artery ligation and hypoxia) or direct needle injury to brain tissue. At defined times after injury, the presence of apoptosis was investigated by cell morphology, in situ end labeling, electron microscopy and poly-ADP-ribose polymerase (PARP) cleavage. Injury to the rat forebrain following hypoxia-ischemia increased apoptosis in the internal granular and Purkinje cell layers of the cerebellum, a site distant to that of the primary injury. The number of apoptotic cells in the cerebellum was significantly related to cell death in the hippocampus. Similarly, direct needle injury to the forebrain resulted in extensive apoptotic cell death in the cerebellum. These results emphasize the intimate relationship between defined neuronal populations in relatively distant brain areas and suggest a cellular basis for diaschisis. [source]