102,167 research outputs found
Interhemispheric transfer of voluntary motor commands in man
No full textThe lack of callosal fibres between homotopic areas of the hand in the
sensorimotor cortex in man and its possible functional correlates were
investigated in normal adult subjects by comparing simple reaction times (RTs) of
voluntary movements triggered by a somaesthetic stimulus to the same or opposite
side of the body. An air jet was delivered to the skin of distal (index finger)
or proximal (shoulder) ipsi- or contralateral zones, and triggered voluntary
extension of the index finger or flexion of the forearm. The RT was measured from
the arrival of the stimulus to the skin to the onset of the surface EMG of the
muscle extensor indicis proprius or biceps brachii. The RTs of the contralateral
finger movements triggered by either proximal or distal skin stimuli were
significantly longer than the RTs of the corresponding ipsilateral movements
(mean difference 11.72 and 15.10 msec respectively). When the task was flexion of
the forearm, the differences in RTs between contra- and ipsilateral movements
were instead compatible with a transcallosal transfer (mean difference about 2
msec in both cases). It is concluded that transcallosal connections between hand
sensorimotor areas are conceivably absent also in man. Furthermore, the delay in
contralateral distal performance appears to be due to a lack of transfer of the
command through the motor areas, rather than to a lack of transfer of the
triggering cutaneous afferent information to the performing hemisphere
Poincaré duality isomorphisms in tensor categories
No full textIf for a vector space V of dimension g over a characteristic zero field we denote by Lambda V-i its alternating powers, and by V-v its linear dual, then there are natural Poincare isomorphisms:
Lambda V-i(v )congruent to Lambda Vg-i.
We describe an analogous result for objects in rigid pseudo-abelian Q-linear ACU tensor categorie
Experiences from the accident of Seveso
No full textPreliminary data of the effects of the Seveso accident (Italy) are describe
The impact of local regulations on land use planning for seveso sites: SMEs perspective
No full textAccording to the Piedmont Seveso laws, it is compulsory for the Municipalities with a Seveso plant within their territory the drafting of a Technical Document called RIR - Rischio di Incidente Rilevante (Major Risk Accident). The document requires first of all a detailed investigation concerning all the potential dangerous enterprises settled in the district: obviously the Seveso plants, but also all the typologies of production that involve high temperature/high pressure, or employment of radiations and carcinogenic substances. Furthermore, the Municipalities have a to identify another category of plants, which is not specified in the national laws: The "Subthreshold" plants, which hold an amount of hazardous substances equal to 20% of the thresholds fixed by the Decree no. 334/1999 to be identified as a Seveso plant. The process for the identification of non-Seveso plants is based on questionnaires sent to the enterprises: it can be very difficult both for the Municipalities and the companies, because they frequently aren't accustomed to the prescriptions and terms of the Seveso laws. Furthermore, after this step, the Municipalities could require another effort to the plant managers, concerning the adoption of measures for the environmental protection, as prescribed in the Provincial Guidelines. The present paper analyses the Piedmont Seveso laws from an industrial point of view, in order to highlight the difficulties that the application of the Land Use Planning local regulations could find in a complex and multifaceted world of SMEs in a period of economic depression
Physical security barriers and protection distances for seveso sites
No full textSeveso III Directive (2012/18/EU) requires operators to demonstrate that they have identified major accident hazards and scenarios, and that they have implemented adequate actions to prevent such accidents. Safety reports issued under the Seveso Directive specifically address accident scenarios caused by technical or human failures. Scenarios caused by intentional acts are usually not considered, even if they have a wide potential to harm the workers and the exposed population in the vicinity of Seveso sites. The present contribution focuses on the characterization of physical security-related scenarios in the framework of safety and security management of Seveso sites, identified taking advantages of the potential synergies between safety and security studies. The role of physical security barriers is explored. Finally, the use of protection distances from critical and vulnerable units is presented to support the selection of the barriers. Copyright © 2019, AIDIC Servizi S.r.l
RECIPROCITY LAWS FOR BALANCED DIAGONAL CLASSES
No full textThis article constructs a 3-variable balanced diagonal class kappa(f, g, h) in the cohomology of the Galois representation associated to a self-dual triple (f, g, h) of p-adic Hida families. Its first main result (Theorem A of Section 1.1) establishes an explicit reciprocity law relating kappa(f, g, h) to the unbalanced Garrett-Rankin p-adic L-function attached to (f, g, h). The class kappa(f, g, h) arises from the p-adic interpolation of diagonal classes in the Bloch-Kato Selmer groups of the specializations of (f, g, h) at balanced triples of classical weights. As a consequence, the value of kappa(f, g, h) at a specialization (f, g, h) of (f, g, h) at an unbalanced triple of classical weights is a p-adic limit of crystalline classes. Our second main result (Theorem B of Section 1.2) shows that the obstruction to the crystallinity of an appropriate derivative of kappa(f, g, h) at (f, g, h) is encoded in the central critical value of the complex L-function of f circle times g circle times h
Donne e scienza: a che punto siamo?
No full textLe donne sono in numero maggiore tra gli iscritti all’università, tra i laureati e in molti paesi anche tra i dottori di ricerca, ma laureate e specializzate entrano con più difficoltà degli uomini nel mondo del lavoro e soprattutto accedono di meno alle professioni legate alla ricerca. Questo capitolo intende presentare un’analisi secondaria dei dati e delle informazioni più rilevanti e più recenti, provenienti dalle più autorevoli fonti nazionali e internazionali, utili per comprendere lo stato dei rapporti di genere nel mondo della scienza in Italia e in Europa
Estimation of general Hamiltonian parameters via controlled energy measurements
No full textThe quantum Cramér-Rao theorem states that the quantum Fisher information bounds the best achievable precision in the estimation of a quantum parameter ξ. This is true, however, under the assumption that the measurement employed to extract information on ξ is regular, i.e., neither its sample space nor its positive-operator valued elements depend on the (true) value of the parameter. A better performance may be achieved by relaxing this assumption. In the case of a general Hamiltonian parameter, i.e., when the parameter enters the system's Hamiltonian in a nonlinear way (making the energy eigenstates and eigenvalues ξ dependent), a family of nonregular measurements, referred to as controlled energy measurements, is naturally available. We perform an analytic optimization of their performance, which enables us to compare the optimal controlled energy measurement with the optimal Braunstein-Caves measurement based on the symmetric logarithmic derivative. As the former may outperform the latter, the ultimate quantum bounds for general Hamiltonian parameters are different than those for phase (shift) parameters. We also discuss in detail a realistic implementation of controlled energy measurements based on the quantum phase estimation algorithm and work out a variety of examples to illustrate our results
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