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The current density distribution in HTS tapes for power transmission applications plays a key role for the determination of the conductor dissipation both in normal and in overload conditions, as occurring for example during transmission lines faults. We have tested the response of Ag/Bi2223 tapes in dc and ac self field transport current in order to determine the repartition of current between the superconducting material and the silver sheath, in particular in the high current range. The experimental results are compared with the results of a numerical calculation model able to determine the tapes self-field current density distribution both above and below Ic. The same model is also used to calculate the tape's AC losses. The results are compared with the measured values.

Bi-2223 silver sheathed tapes are currently used in prototypes of HTSC power devices, where they generally carry an electrical AC current and are exposed to an alternating magnetic field that may have different orientation with respect to the tape. In this work, the authors describe the experimental set-up for measuring AC losses of HTSC tapes due to the simultaneous presence of AC current and AC magnetic field. The experimental results have been compared and contrasted with a numerical model purposely developed for the evaluation of current distribution and AC loss in HTSC tapes.

Candidate inert matrix materials for actinide transmutation (MgAl 2 O 4 , CeO 2 ) or immobilization (ZrSiO 4 ) containing 241 Am were characterized. The currently most considered material, ZrO 2 , was produced, with La 2 O 3 as stand-in for Am, and with and without simulated fission products to investigate burnup effects. The oxygen potential was measured using an EMF cell. The accumulation of radiation damage due to Am decay was investigated by periodically measuring lattice parameters and hardness. Sequential leaching tests in deionized water, aimed at correlating the leaching behaviour of Am and of the matrix with radiation damage, showed significant release of Am and of some matrix components.

The DC and AC behaviour of Ag-sheathed Bi 2 Sr 2 Ca 2 Cu 3 O x (BSCCO-2223) tapes, arranged in a z-stack configuration, are investigated. The number of tapes in the stack can be varied, from one (single tape) to four, as well as the inter-tape separation. Tapes are isolated and connected in series to ensure a uniform current distribution among the tapes. The critical currents and the average AC losses per tape as a function of the transport current are measured. By increasing the number of tapes or/and reducing the separation between them, the critical current of each tape is decreased while the average losses are increased. Tapes in a stack are found to be electromagnetically coupled, the degree of this coupling being dependent on the separation among them. Theoretical models are provided to explain the experimental results.

Drawing on recent empirical work, this philosophical paper explores some possible contributions of emotion to self-deception. Three hypotheses are considered: (1) the anxiety reduction hypothesis: the function of self-deception is to reduce present anxiety; (2) the solo emotion hypothesis: emotions sometimes contribute to instances of self-deception that have no desires among their significant causes; (3) the direct emotion hypothesis: emotions sometimes contribute directly to self-deception, in the sense that they make contributions that, at the time, are neither made by desires nor causally mediated by desires. It is argued that (1) is false and that (3) is defensible and more defensible than (2).

In the present study we investigated the role of two isoforms of protein kinase C in the mitogenic signal of epidermal growth factor (EGF) in primary culture of chick embryo hepatocytes. The down-regulation of PKCalpha by long-term exposure to phorbol myristate acetate (PMA) provoked a reduced mitogenic response to EGF while the down-regulation of PKCepsilon with oligonucleotide antisense had no effect on the stimulation of DNA synthesis, assayed as thymidine incorporation. EGF enhanced H3 diacylglycerol (DAG) production by cells preincubated with H3myristic acid, but did not increase the production of inositol 1-4-5-trisphosphate (IP3). EGF produced an increase in the release of arachidonic acid and prostaglandin E2 (PGE2) in the extracellular medium. The increase was blocked by specific inhibitors (quinacrine and AACOCF3) of phospholipase A2 (PLA2) and was inhibited by down-regulation of PKCalpha, demostrating that this isoform is involved in arachidonic acid production. DAG and arachidonic acid produced an additional effect on thymidine incorporation. The treatment with PLA2 inhibitors, which block the increase in arachidonic acid, decreased the effect of EGF on DNA synthesis. These results suggest that in chick embryo hepatocytes PKCalpha is the main isoform involved in EGF-induced DNA synthesis. Its rapid activation is dependent on DAG production and induces an increased production of arachidonic acid and prostaglandin which are involved in the mitogenic activity.

Dans le cadre de la psychologie de la prise de decision, l'A. montre que la decision d'agir consiste en la performance d'une action mentale, mais qu'elle laisse entiere la question de la formation de l'intention. L'A. interroge le mode d'acquisition de l'intention au meme titre que celui de la croyance ou du desir.

Dans le cadre du debat sur les notions d'intention et d'action intentionnelle, l'A. mesure la validite de l'argument simple de la circularite (unadorned circularity argument) concernant la possibilite d'une explication de l'intention en termes d'attitude executive envers un plan defini comme le contenu representationnel de l'intention.

The Campi Flegrei caldera (Italy) has been the site of intense seismic activity over the past decades. This area is densely populated and includes important towns such as Napoli with historical sites and supporting many industries. For the proper use and management of the region, the evaluation of the dynamic properties of near-surface rocks is necessary. The volcanological pattern has been reconstructed from the lithostratigraphies of several drillings. The most interesting and widespread pyroclastic products are the pozzolana deposit (soil) and the Neapolitan Yellow Tuff (rock). Both pozzolana and tuff products are covered by recent eluvial and coastal sandy deposits and younger volcanic products (

In instances of "twisted" self-deception, people deceive themselves into believing things that they do not want to be true. In this, twisted self-deception differs markedly from the "straight" variety that has dominated the philosophical and psychological literature on self-deception. Drawing partly upon empirical literature, I develop a trio of approaches to explaining twisted self-deception: a motivation-centered approach; an emotion-centered approach; and a hybrid approach featuring both motivation and emotion. My aim is to display our resources for exploring and explaining twisted self-deception and to show that promising approaches are consistent with a plausible position on straight self-deception.

This paper raises a pair of objections to the novel libertarian position advanced in Robert Kane's recent book, The Significance of Free Will.The first objection's target is a central element in Kane's intriguing response to what he calls the “Intelligibility” and “Existence” questions about free will. It is argued that this response is undermined by considerations of luck.The second objection is directed at a portion of Kane's answer to what he calls “The Significance Question” about free will: “Why do we, or should we, want to possess a free will that is incompatible with determinism? Is it a kind of freedom ‘worth wanting’... and, if so, why?” A desire for “objective worth” has a featured role in his answer. However, a compatibilist can have that desire.

My topic lies on conceptual terrain that is quite familiar to philosophers. For others, a bit of background may be in order. In light of what has filtered down from quantum mechanics, few philosophers today believe that the universe is causally deterministic (or “deterministic,” for short). That is, to use Peter van Inwagen's succinct definition of “determinism,” few philosophers believe that “there is at any instant exactly one physically possible future.” Even so, partly for obvious historical reasons, philosophers continue to argue about whether free will and moral responsibility are compatible with determinism. Compatibilists argue for compatibility, and incompatibilists argue against it. Some incompatibilists maintain that free will and moral responsibility are illusions. But most are libertarians, libertarianism being the conjunction of incompatibilism and the thesis that at least some human beings are possessed of free will and moral responsibility.

Autonomous Agents addresses the related topics of self-control and individual autonomy. "Self-control" is defined as the opposite of akrasia-weakness of will. The study of self-control seeks to understand the concept of its own terms, followed by an examination of its bearing on one's actions, beliefs, emotions, and personal values. It goes on to consider how a proper understanding of self-control and its manifestations can shed light on personal autonomy and autonomous behaviour. Perspicuous, objective, and incisive throughout, Alfred Mele makes a convincing case for the value of individual autonomy.

Can the existence of motivationally biased beliefs plausibly be explained without appealing to actions that are aimed at producing or protecting these beliefs? Drawing upon some recent work on everyday hypothesis testing, I argue for an affirmative answer. Some theorists have been too quick to insist that motivated belief must involve, or typically does involve, our trying to bring it about that we acquire or retain the belief, or our trying to make it easier for ourselves to believe a preferred proposition—and too quick to conclude that such exercises of agency are involved in specific instances of the phenomenon. There are alternative ways to accommodate the data, and it is far from clear that the “agency view” accommodates them better.

L'A. defend la these selon laquelle la refutation semi-compatibiliste du scepticisme et la critique de l'incompatibilisme developpes par J. Fischer dans son ouvrage intitule «The metaphysics of free will» sous-estime les ressources de la pensee libertaire concernant le debat sur le determinisme causal, la volonte libre et la responsabilite morale. Examinant les contre-exemples de Frankfurt invalidant le principe des possibilites alternatives, l'A. defend la these du libertarisme faible en matiere de determinisme et mesure les consequences d'une telle position au regard du libertarisme fort

Recent technological developments in manufacturing high-temperature superconductor (HTSC) tapes have improved their mechanical and electrical performances considerably. Now, a near future when HTSC cables will become a reality can finally be forecast. This brings about the need for work in the field of quality control and diagnostics of HTSC tapes. A new methodology for the analysis of the behaviour of tapes aged under different kinds of mechanical stresses is presented in this paper. The methodology is based on a probabilistic approach, where the two-parameter Weibull function is used to fit the cumulative and density probability distributions obtained from experimental V-I characteristics by numerical-analytical differentiation. Experimental results relevant to both long-term (aging) and short-term tests performed on 2223-BSCCO tapes are presented and discussed. It is shown that the time behaviour of Weibull function parameters provides useful information on the level of aging and on the kind of damage occurring to the tapes. In particular, the comparison between the results obtained from long-term and short-term tests, as well as from different types of mechanical stresses, points out that the shape of probability distributions constitutes a valuable diagnostic tool to distinguish between local or overall degradation and helps in identifying damage location.

A new approach to the dynamical evolution of a waveguide laser is presented which goes beyond the usual Maxwell-Bloch (MB) equations in that it takes fully into account the phase of the matter quantum field that describes the atomic systems. As an experimental check of its effectiveness, we analyze in its light a recent set of experiments on the effects of a "dephasing" of the electromagnetic laser field that find no explanation within the MB equations but, on the contrary, are in very good agreement with its expectations.

Improved measuring procedures and interpretation efforts have shown that the critical state model is fully applicable for describing the behaviour of HTS tapes for power applications. By this means, we could consistently analyse magnetic and transport measurements and study possible inhomogeneities and geometrical peculiarities in BSCCO-2223 tapes. Examples of such an analysis are given in this contribution. Losses in multistrand conductors require a more complex modellization and further development of the experimental procedures; the results of a.c. transport measurements on a 13 m long, multilayer, prototype conductor sample are also discussed here.

A longitudinal study was conducted to assess the value of quantitative ultrasound (QUS) measurement in predicting the risk of fracture and to evaluate how QUS parameters change with ageing and the climacteric. A group of 211 female subjects underwent assessment by QUS at the distal metaphysis of the first phalanx of the last four fingers of the hand on two occasions 3 years apart. The subjects were selected from outpatients attending the orthopaedic clinic, provided they were not affected by metabolic disease or under treatment with drugs known to interfere with bone metabolism. In vivo the coefficient of variation and the standardized coefficient of variation of the QUS device were respectively 0.5% and 3.5%. The correlation between the values of the amplitude-dependent speed of sound (AD-SoS) in the two measurements was r = 0.92. In 77.3% of the subjects during the observation period we recorded a reduction in AD-SoS. During the study 22 fractures were observed in peripheral sites, 8 of which were associated with 'low-energy trauma'. By multiple logistic regression analysis we found that the relative risk of fracture for a 1 SD reduction in AD-SoS was 1.5 (95% CI 1.1-1.7) (p < 0.03). The percentage of low-energy fractures significantly increased among those subjects with an AD-SoS value lower than 1850 m/s (T-score < -3.5) at the first examination (p

Specimens of 2223-BSCCO tapes were subjected to mechanical degradation, measuring, after and before degradation, the voltage-current (V-I) characteristic. The two-parameter Weibull function was used to fit the cumulative and density probability distributions (obtained fromV-I data by numerical-analytical differentiation). It is shown that Weibull-function parameter values are sensitive to weak points generated in the tapes by mechanical stress, thus providing clear evidence of the presence of defects. In particular, attention is focused to the answer of diagnostic procedures resorting to the Weibull distribution to weak points which can be encountered in a HTSC tape typically used for high-voltage cables. These defects can arise due to aging or be already present in the new tape, thus the proposed procedure has both diagnostic and quality control features.

AC losses in the transport regime were measured in Ag-sheathed (Bi,Pb)/sub 2/Sr/sub 2/Ca/sub 2/Cu/sub 3/O/sub x/ (Ag/2223) tapes at 77 K in the frequency range 35-180 Hz. The samples were multifilamentary, prepared by OPIT (oxide powder in tube) technique, and "concentric" prepared by the wire-in-tube technique, and they had different superconducting core geometries. Measured losses were confirmed to be hysteretic in nature in the examined frequency range. The experimental results are compared with the prediction of the elliptical and thin strip Norris model.

Specimens of 2223-BSCCO tapes were subjected to mechanical aging, with their voltage-current (V-I) characteristic measured at different aging times. Two types of mechanical stresses were applied: cyclic (vibration) and static. Probability distributions were obtained from V-I data by numerical-analytical differentiation, and the Weibull function was used to fit the cumulative and density probability distributions thus obtained. It is shown that the time behavior of the parameters of the Weibull functions thus obtained provides useful information on the level and kind of degradation.

AC losses in two multifilamentary BiSrCaCuO-2223/Ag tapes differing in number of filaments were determined by transport and magnetic measurements. In the latter, the AC field was directed perpendicularly to the wide side of the tape and the model of a superconducting strip was used in the calculations. Comparison of the experimental data with theoretical models confirmed that when the tape carries a transport AC current, strong electromagnetic coupling between filaments leads to non-uniform distribution of current among the individual filaments. On the contrary, the results of magnetic measurements were consistently explained only if we supposed a negligible electromagnetic coupling between filaments. This effect could explain the commonly observed discrepancy between AC transport and magnetic loss measurements. By taking this effect into account, the apparent lack of consistency in the Jc value of the superconductor derived from transport and magnetic experiments disappears.

This response addresses seven main issues: (1) alleged evidence that in some instances of self-deception an individual simultaneously possesses “contradictory beliefs”; (2) whether garden-variety self-deception is intentional; (3) whether conditions that I claimed to be conceptually sufficient for self-deception are so; (4) significant similarities and differences between self-deception and interpersonal deception; (5) how instances of self-deception are to be explained, and the roles of motivation in explaining them; (6) differences among various kinds of self- deception; (7) whether a proper conception of self-deception implies that definitive ascriptions of self-deception to individuals are impossible.

In the framework of Quantum Field Theory we propose a novel approach to the theory of bosonic simple liquids, formulated in terms of a scalar, complex quantum field, the wave-field Ψ(x,t). The problem is treated in a mean-field approximation, diagonalizing the quadratic part of the Hamiltonian à la Bogoliubov and calculating in a perturbative scheme the one-loop correction to the self-energy function. We derive the dispersion relation and the dynamic and static structure factors of the liquid 4 He , obtaining results that are successfully compared with experimental data.

L'A. mesure la possibilite de l'action akratique, c'est-a-dire de l'action intentionnelle contraire a ce que l'agent juge de meilleur a faire, rejetee par Socrate dans le «Protagoras» de Platon (352b-358d). Examinant les concepts de jugement influence par la motivation et de maitrise de soi, l'A. montre que l'agent akratique socratique, face a la tentation, change d'etat d'esprit en ce qui concerne ce qu'il y a de meilleur a faire

What role, if any, can moral theory properly play in the project of constructing a theory of motivation? Answering this question is a task for a book, not an article. This article addresses a piece of the puzzle. I will develop a problem for the conjunction of two theses in moral philosophy that jointly imply that moral agents are possessed of motivational attitudes of a certain kind-and, hence, that we ourselves are possessed of such attitudes, on the attractive assumption that we are moral agents. The first thesis is cognitivism about first-person moral ought beliefs-the thesis that such beliefs are attitudes with truthvalued content, and that not all such beliefs are doomed to be false, as they would be if an "error theory" about them were true.' The second thesis is a robust internalism about first-person moral ought beliefs-the thesis that, necessarily, any belief that one (oneself) ought, morally, to A constitutes motivation to A. I will argue that the combination of moral cognitivism and this robust internalism places our moral agency at serious risk, and I will extend the argument to a less demanding brand of internalist moral cognitivism.2 I will not

Rejetant les arguments utilitaristes en faveur de l'application des notions d'intention et d'intentionnalite dans le domaine de la responsabilite morale, l'A. mesure le role conceptuel de l'intention et de l'action intentionnelle dans les schemes explicatifs de la philosophie de l'esprit, ainsi que dans les schemes evaluatifs de la philosophie morale

L'A. defend la these selon laquelle il existe des raisons speciales qui motivent l'intention d'un acte et qui ne sont pas celles qui motivent l'acte lui-meme. Ces raisons speciales qui motivent l'intention d'un acte peuvent jouer un role deliberatif dans la formation de l'intention de cet acte

Benjamin Libet contends both that “the brain ‘decides’ to initiate or, at least, prepare to initiate [certain actions] before there is any reportable subjective awareness that such a decision has taken place” and that “If the ‘act now’ process is initiated unconsciously, then conscious free will is not doing it.” Elsewhere, I have argued that the claims I just reported are not justified by the data Libet and others offer in support of them. Here I review some of the problems one encounters in attempting to move from Libet’s data to his conclusions.

This article examines the work of two figures in fields whose work has had a significant impact on recent free-will debates, neuroscientist Benjamin Libet and psychologist Daniel Wegner. Libet's groundbreaking experimental studies on human subjects relating brain activities to the appearance or production of conscious experience, volition, and willed action have been much discussed by philosophers and scientists over the past few decades and have influenced subsequent scientific research on these subjects. The second half of the article deals with the arguments of psychologist Daniel Wegner, whose book, The Illusion of Conscious Will, has had a significant impact on free-will debates since its publication. Wegner argues that our experience of conscious control over our willed actions is an illusion. Wegner appeals in part to the Libet experiments and other neuroscientifc experiments on voluntary action.