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Popular Notion (popular + notion)
Selected AbstractsNMR and the uncertainty principle: How to and how not to interpret homogeneous line broadening and pulse nonselectivity.CONCEPTS IN MAGNETIC RESONANCE, Issue 5 2008IV. (Un?)certainty Abstract Following the treatments presented in Parts I, II, and III, I herein address the popular notion that the frequency of a monochromatic RF pulse as well as that of a monochromatic FID is "in effect" uncertain due to the (Heisenberg) Uncertainty Principle, which also manifests itself in the fact that the FT-spectrum of these temporal entities is spread over a nonzero frequency band. I will show that the frequency spread should not be interpreted as "in effect" meaning a range of physical driving RF fields in the former, and "spin frequencies" in the latter case. The fact that a shorter pulse or a more quickly decaying FID has a wider FT-spectrum is in fact solely due to the Fourier Uncertainty Principle, which is a less well known and easily misunderstood concept. A proper understanding of the Fourier Uncertainty Principle tells us that the FT-spectrum of a monochromatic pulse is not "broad" because of any "uncertainty" in the RF frequency, but because the spectrum profile carries all of the pulse's features (frequency, phase, amplitude, length, temporal location) coded into the complex amplitudes of the FT-spectrum's constituent eternal basis harmonic waves. A monochromatic RF pulse's capability to excite nonresonant magnetizations is in fact a purely classical off-resonance effect that has nothing to do with "uncertainty". Analogously, "Lorentzian lineshape" means exactly the same thing physically as "exponential decay," and all inferences as to the physical reasons for that decay must be based on independent assumptions or observations. © 2008 Wiley Periodicals, Inc. Concepts Magn Reson Part A 32A: 373,404, 2008. [source] NMR and the uncertainty principle: How to and how not to interpret homogeneous line broadening and pulse nonselectivity.CONCEPTS IN MAGNETIC RESONANCE, Issue 4 2008Abstract Following the treatments presented in Parts I and II, I herein discuss in more detail the popular notion that the frequency of a monochromatic RF pulse as well as that of a monochromatic FID is "in effect" uncertain due to the (Heisenberg) Uncertainty Principle, which also manifests itself in the fact that the FT-spectrum of these temporal entities is spread over a nonzero frequency band. In Part III, I continue my preliminary review of some further fundamental concepts, such as the Heisenberg and Fourier Uncertainty Principles, that are needed to understand whether or not the NMR linewidth and the RF excitation bandwidth have anything to do with "uncertainty". The article then culminates in re-addressing our Two NMR Problems in a more conscientious frame of mind by using a more refined formalism. The correct interpretation of these problems will be discussed in Part IV. © 2008 Wiley Periodicals, Inc. Concepts Magn Reson Part A 32A: 302,325, 2008. [source] Actualism and the Fascist Historic ImaginaryHISTORY AND THEORY, Issue 2 2003Claudio Fogu This essay argues that, just like liberalism and communism, fascist ideology was based on a specific philosophy of history articulated by Giovanni Gentile in the aftermath of World War I. Gentile's actualist notion that history "belongs to the present" articulated an immanent vision of the relationship between historical agency, representation, and consciousness against all transcendental conceptions of history. I define this vision as historic (as opposed to "historical") because it translated the popular notion of historic eventfulness into the idea of the reciprocal immanence of the historical and the historiographical act. I further show that the actualist philosophy of history was historically resonant with the Italian experience of the Great War and was culturally modernist. I insist, however, that the actualist catastrophe of the histori(ographi)cal act was also genealogically connected to the Latin-Catholic rhetorical signification of "presence" that had sustained the development of Italian visual culture for centuries. Accordingly, I argue that the fascist translation of actualism into a historic imaginary was at the root of Italian fascism's appeal to both masses and intellectuals. Fascism presented itself as a historic agent that not only "made history," but also made it present to mass consciousness. In fact, I conclude by suggesting that the fascist success in institutionalizing a proper mode of historic representation in the 1920s, and a full-blown historic culture in the 1930s, may have also constituted a fundamental laboratory for the formation of posthistoric(al) imaginaries. [source] Staff gender ratio and aggression in a forensic psychiatric hospitalINTERNATIONAL JOURNAL OF MENTAL HEALTH NURSING, Issue 2 2006Michael Daffern ABSTRACT:, Gender balance in acute psychiatric inpatient units remains a contentious issue. In terms of maintaining staff and patient safety, ,balance' is often considered by ensuring there are ,sufficient' male nurses present on each shift. In an ongoing programme of research into aggression, the authors investigated reported incidents of patient aggression and examined the gender ratio on each shift over a 6-month period. Contrary to the popular notion that a particular gender ratio might have some relationship with the likelihood of aggressive incidents, there was no statistically significant difference in the proportion of male staff working on the shifts when there was an aggressive incident compared with the shifts when there was no aggressive incident. Further, when an incident did occur, the severity of the incident bore no relationship with the proportion of male staff working on the shift. Nor did the gender of the shift leader have an impact on the decision to seclude the patient or the likelihood of completing an incident form following an aggressive incident. Staff confidence in managing aggression may be influenced by the presence of male staff. Further, aspects of prevention and management may be influenced by staff gender. However, results suggest there is no evidence that the frequency or severity of aggression is influenced by staff gender ratio. [source] Family therapy by default: developing useful fall-back positions for therapistsJOURNAL OF FAMILY THERAPY, Issue 3 2006Sigurd Reimers This article looks at some of the effects on practitioners of the increasing complexity and variety of ideas within the family therapy field. In adopting the currently popular notion of ,default position' from information technology, I argue that therapists can easily feel that their work has a random quality to it. I examine how our own default positions can be based on force of habit, a quest for novelty or the effects of stress. Some suggestions are offered for how we can more accurately go about choosing ideas that will be of help to the families with which we work and to ourselves. [source] | |||||||||||||