A Functional and Lagrangian Formulation of Two-Dimensional Topological Gravity

We reconsider two-dimensional topological gravity in a functional and lagrangian framework. We derive its Slavnov-Taylor identities and discuss its (in)dependence on the background gauge. Correlators of reparamerization invariant observables are shown to be globally defined forms on moduli space. The potential obstruction to their gauge-independence is the non-triviality of the line bundle on moduli space ${\cal L}_x$, whose first Chern-class is associated to the topological invariants of Mumford, Morita and Miller. Based on talks given at the Fubini Fest, Torino, 24-26 February 1994, and at the Workshop on String Theory, Trieste, 20-22 April 1994.Comment: 11 pages, harvmac, CERN-TH-7302/94, GEF-Th-6/199

Syllabic effects in Italian lexical access

Two cross-modal priming experiments tested whether lexical access is constrained by syllabic structure in Italian. Results extend the available Italian data on the processing of stressed syllables showing that syllabic information restricts the set of candidates to those structurally consistent with the intended word (Experiment 1). Lexical access, however, takes place as soon as possible and it is not delayed till the incoming input corresponds to the first syllable of the word. And, the initial activated set includes candidates whose syllabic structure does not match the intended word (Experiment 2). The present data challenge the early hypothesis that in Romance languages syllables are the units for lexical access during spoken word recognition. The implications of the results for our understanding of the role of syllabic information in language processing are discussed

On the Semi-Relative Condition for Closed (TOPOLOGICAL) Strings

We provide a simple lagrangian interpretation of the meaning of the $b_0^-$ semi-relative condition in closed string theory. Namely, we show how the semi-relative condition is equivalent to the requirement that physical operators be cohomology classes of the BRS operators acting on the space of local fields {\it covariant} under world-sheet reparametrizations. States trivial in the absolute BRS cohomology but not in the semi-relative one are explicitly seen to correspond to BRS variations of operators which are not globally defined world-sheet tensors. We derive the covariant expressions for the observables of topological gravity. We use them to prove a formula that equates the expectation value of the gravitational descendant of ghost number 4 to the integral over the moduli space of the Weil-Peterson K\"ahler form.Comment: 10 pages, harvmac, CERN-TH-7084/93, GEF-TH-21/199

Large Deviation Approach to the Randomly Forced Navier-Stokes Equation

The random forced Navier-Stokes equation can be obtained as a variational problem of a proper action. By virtue of incompressibility, the integration over transverse components of the fields allows to cast the action in the form of a large deviation functional. Since the hydrodynamic operator is nonlinear, the functional integral yielding the statistics of fluctuations can be practically computed by linearizing around a physical solution of the hydrodynamic equation. We show that this procedure yields the dimensional scaling predicted by K41 theory at the lowest perturbative order, where the perturbation parameter is the inverse Reynolds number. Moreover, an explicit expression of the prefactor of the scaling law is obtained.Comment: 24 page

A PRELIMINARY FEASIBILITY ANALYSIS ABOUT THE STRUCTURAL HEALTH MONITORING OF RAILWAY CONCRETE SLEEPERS BY ACOUSTIC EMISSION AND DIGITAL IMAGE CORRELATION

Railway concrete sleepers are made out of steel reinforced concrete and are a safety critical component of the railway track. Different kinds of failure are observed during service and this requires a maintenance plan involving non-destructive testing. Nevertheless, shifting from a non-destructive approach to structural health monitoring has shown relevant opportunities to increase in-service reliability and to decrease the costs of maintenance. From this point of view, the present paper describes a preliminary feasibility analysis about the application of acoustic emission for detection of cracks in prestressed concrete sleepers. For the purpose of assessment, obtained results are compared with other methods, such as digital image correlation and visual testing. Encouraging results indicate the possibility to carry out more validating tests in order to get the engineering of a suitably cheap monitoring system for in-service applications

A call to action by the italian mesotherapy society on scientific research

: Mesotherapy (local intradermal therapy, LIT) is a technique used to slowly spread drugs in tissues underlying the site of injection to prolong the pharmacological effect with respect to intramuscular injection. Recommendations for proper medical use of this technique have been made for pain medicine and rehabilitation, chronic venous disease, sport medicine, musculoskeletal disorders, several dermatological conditions, skin ageing, and immune-prophylaxis. Although mesotherapy is considered a valid technique, unresolved questions remain, which should be answered to standardize methodology and dosing regimen as well as to define the right indications in clinical practice. New randomized controlled trials are needed to test single products (dose, frequency of administration, efficacy and safety). Even infiltration of substances for dermo-cosmetic purposes must be guided by safety and efficacy tests before being proposed by mesotherapy. In this article, we put forth a preclinical and clinical research plan and a health technology assessment as a call to action by doctors, researchers and scientific societies to aid national health authorities in considering mesotherapy for prevention, treatment and rehabilitation paths

In-flight performances of the BeppoSAX γ\gamma-Ray Burst Monitor

The Italian-Dutch satellite for X-ray Astronomy BeppoSAX is successfully operating on a 600 km equatorial orbit since May 1996. We present here the in-flight performances of the Gamma Ray Burst Monitor experiment during its first year of operation. The GRBM is the secondary function of the four CsI(Na) slabs primarily operating as an active anticoincidence of the PDS hard X-ray experiment.. It has a geometric area of about 4000 cm2 but, due to its location in the core of the satellite its effective area is dependent on the energy and direction of the impinging photons. A dedicated electronics allows to trigger on cosmic gamma-ray bursts. When the trigger condition is satisfied the light curve of the event is recorded from 8 s before to 98 s after the trigger time, with a maximum time resolution of 0.48 ms, in an energy band of 40-700 keV

Novel compounds targeting the RNA-binding protein HuR : Structure-based design, synthesis and interaction studies

The key role of RNA-binding proteins (RBPs) in regulating post-transcriptional processes and their involvement in several pathologies (i.e., cancer and neurodegeneration) have highlighted their potential as therapeutic targets. In this scenario, Embryonic Lethal Abnormal Vision (ELAV) or Hu proteins and their complexes with target mRNAs have been gaining growing attention. Compounds able to modulate the complex stability could constitute an innovative pharmacological strategy for the treatment of numerous diseases. Nevertheless, medicinal-chemistry efforts aimed at developing such compounds are still at an early stage. As part of our ongoing research in this field, we hereby present the rational design and synthesis of structurally novel HuR ligands, potentially acting as HuR-RNA interferers. The following assessment of the structural features of their interaction with HuR, combining saturation-transfer difference NMR and in silico studies, provides a guide for further research on the development of new effective interfering compounds of the HuR-RNA complex

Morphometric analysis of astrocytes in brainstem respiratory regions

Astrocytes, the most abundant and structurally complex glial cells of the central nervous system, are proposed to play an important role in modulating the activities of neuronal networks, including respiratory rhythm-generating circuits of the preBötzinger complex (preBötC) located in the ventrolateral medulla of the brainstem. However, structural properties of astrocytes residing within different brainstem regions are unknown. In this study astrocytes in the preBötC, an intermediate reticular formation (IRF) region with respiratory-related function, and a region of the nucleus tractus solitarius (NTS) in adult rats were reconstructed and their morphological features were compared. Detailed morphological analysis revealed that preBötC astrocytes are structurally more complex than those residing within the functionally distinct neighboring IRF region, or the NTS, located at the dorsal aspect of the medulla oblongata. Structural analyses of the brainstem microvasculature indicated no significant regional differences in vascular properties. We hypothesize that high morphological complexity of preBötC astrocytes reflects their functional role in providing structural/metabolic support and modulation of the key neuronal circuits essential for breathing, as well as constraints imposed by arrangements of associated neurons and/or other local structural features of the brainstem parenchyma