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The design of an Ambient Assisted Living (AAL) aims to create better living conditions for the elderly, especially those who choose to live in their own houses, as long as possible. To this objective, AAL systems must mainly monitor the health status of the elderly through the analysis of data gathered via technologies based on sensor devices. Sensors networks produce collections of data of fine-grained nature, regarding general information such as device name, data type, data value, timestamp, but also specific one. The data analysis, due to its granularity and heterogeneity, makes very difficult to infer a clear overall view of the status of the elderly, it demands automatic tools for selecting meaningful data and mapping them in a common conceptual schema. In the last decade, ontologies became widely used tool to describe application domains and to enrich data with its meaning. In this paper, we propose an ontology-based methodology to perform semantic queries on a data repository, where records originated from networks of heterogeneous sources are stored. A semantic query is a pattern matching process that supports the recognition of specific temporal sequences of events that can be extracted from fine-grained data. In our framework a domain ontology are exploited at different levels of abstraction and the reasoning techniques are used to pre-process data for the final temporal analysis. The proposed approach is a deliverable of the ongoing AALISABETH project funded by Region Marche Government; while the software component is integrated into the AALISABETH framework.

We propose a mechanism which produces periodic variations of the degree of predictability in dynamical systems. It is shown that even in the absence of noise when the control parameter changes periodically in time, below and above the threshold for the onset of chaos, stochastic resonance effects appears. As a result one has an alternation of chaotic and regular, i.e. predictable, evolutions in an almost periodic way, so that the Lyapunov exponent is positive but some time correlations do not decay., 9 Pages + 3 Figures, RevTeX 3.0, sub. J. Phys. A

The energy of a finite system thermally connected to a thermal reservoir may fluctuate, while the temperature is a constant representing a thermodynamic property of the reservoir. The finite system can also be used as a thermometer for the reservoir. From such a perspective, the temperature has an uncertainty, which can be treated within the framework of estimation theory. We review the main results of this theory and clarify some controversial issues regarding temperature fluctuations. We also offer a simple example of a thermometer with a small number of particles. We discuss the relevance of the total observation time, which must be much longer than the decorrelation time. © 2011 American Association of Physics Teachers.

This report deals with 3 cases of internal auditory canal metastasis, an extremely rare lesion, few cases having been reported in the international literature. Since pre-operative diagnosis is fundamental in the planning of a correct therapeutic strategy, it is important that the neurotologist be aware of the possibility of their occurrence in this particular area. Metastasis can occur unilaterally as well as bilaterally; the latter being the case in 1 of the patients described herein. Correct pre-operative diagnosis is particularly difficult in patients in whom the primary tumour has not been detected at the time of identification of the lesion in the internal auditory canal. The only characteristic, specific of metastasis, is the presence of multifocal cerebral lesions. However, these were detected in only 1 of the present cases. On the contrary, in cases of a single metastasis, both magnetic resonance imaging and computed tomography usually fail to show any distinctive feature when compared to the most common tumours of the internal auditory canal (vestibular schwannomas and meningiomas). Bilateral metastases can also be misdiagnosed as neurofibromatosis type 2. Clinical data that should alert the clinician are: rapidly progressive sensorineural hearing loss, followed by onset of progressive facial nerve weakness. Radiotherapy and/or chemotherapy are the two main treatment modalities, while surgical removal is reserved for selected cases of a single metastasis. Albeit, due to the paucity of specific radiological and clinical characteristics, surgical removal is often necessary to reach the correct diagnosis, as occurred in 2 of the present patients.

High resolution computed tomography (CT) is presently the most accurate technique to study the temporal bone. Nevertheless, there is no general agreement about its usefulness in pre-operative evaluation of chronic otitis media. Indeed, if we rule out some exceptions, CT is not fundamental for diagnosis which can often be obtained through an accurate otomicroscopy. The Otology Group in Piacenza applies the following absolute indications for pre-operative CT in chronic otitis media: 1) difficult otomicroscopy evaluation; 2) suspected petrous bone cholesteatoma; 3) dubious diagnosis; 4) suspect of malformations; 5) review of cases that had previously undergone mastoidectomy; 6) suspected intracranial complications and/or meningoencephalic herniation (in this case also a magnetic resonance imaging must be performed). With the exception of these specific conditions, pre-operative CT is useless in cases of simple chronic otitis. However, when a cholesteatoma is suspected, CT can provide the surgeon, particularly when inexperienced, useful, but not indispensable, informations. Pre-operative knowledge of these informations can allow a more accurate evaluation of the case, with a better planning of the surgical procedure, in order to ensure a more specific informed consent. Finally, the Authors point out the fact that surgeon must be able to interpret by his own the CT data to have a real advantage by this examination.

The translabyrinthine approach has long been, and in some centers is still, considered inadequate for the removal of large acoustic neuromas (AN). Over the years, with experience, the original technique has been modified, extending the approach to what is now called the enlarged translabyrinthine (ET) approach. Applying these modifications, between April 1987 and February 2000, the Gruppo Otologico in Piacenza, Italy removed 132 ANs, 3 cm or larger, from the cerebello-pontine angle. These tumors accounted for 25.9% of the 510 cases of AN to undergo surgery during that period. Of the 132 cases only one patient died and the percentage of complications was very low, generally lower than analogous series published in the literature. Such complications were progressively reduced in time, leading to a significant reduction in the length of post-operative hospitalization: on the average the 8.8 days were reduced to 5.7 in the last 43 cases. Ipsilateral preoperative hearing, inevitably sacrificed using the ET approach, was already significantly compromised in more than 65% of the cases. On the basis of the present data, it can be asserted that tumor diameter does not in any way preclude the use of the ET approach in AN surgery, rather the reduced morbility and shorter post-operative hospitalization make it the approach of choice for large ANs.

Generally the main objective of acoustic neurinoma (AN) surgery is to totally remove the tumor associated with minimum morbidity. Nevertheless, in some cases residual tumor fragments are intentionally or accidentally left in place. These residues can lead to new growth. The present study provides a retrospective analysis of 14 cases of residual AN have undergone surgery at the Otology Group in Piacenza from 1987 to 1999. All these patients had previously undergone at least one retrosigmoidal exeresis although only one had been performed at the Otology Group. All patients except 1 were affected by anacusia at the time of surgery. The list of post-operative deficits included 2 hemipareses, 3 irreversible facial paralysis with consequent corneal opacity in 2 cases, 1 dysmetria and 1 paralysis of the abducent nerve. The patients had also undergone the following additional treatments: 1 emergency revision to drain a cerebellar hematoma, 3 ventricle-peritoneal derivations, 1 double application of stereotactic radiotherapy and 2 surgical procedures for facial plasty. Ten cases underwent the revision surgery at the Otologic Group using a translabyrinthine approach and 4 using a transcochlear approach. Tumor removal was deemed complete in all cases. The sole post-operative complications were a subcutaneous hematoma at the point where abdominal fat was removed and a temporary paralysis of the abducent nerve. Post-operative hospitalization was an average of 6.9 days. Analysis of the results showed that AN must be operated at selected centers in order to reduce the post-operative neurological deficit and the percentage of residual tumor. It also indicated that the retrosigmoid approach has a higher risk of accidentally leaving tumor residues than the other approaches. Finally, in the presence of a residual AN, the translabyrinthine approach offers the greatest advantages.

The objective of this study was to validate measures taken to reduce the number of cerebrospinal fluid (CSF) leaks after removal of vestibular schwannomas to 0.This study was a retrospective case review.The study was conducted at an otology/neurotology tertiary referral center (Gruppo Otologico, Piacenza, Italy).Three hundred thirty-one vestibular schwannoma patients were studied.The enlarged translabyrinthine approach (TLA) was used in all cases, with a number of modifications in the last 200 patients. It was extended in 22 patients with blind sac closure of the external meatus, removal of the posterior bony canal wall, and obliteration of the Eustachian tube and middle ear.Whether patients had a leak through the wound, the nose (rhinoliquorrhea), or the ear (otoliquorrhea) was assessed.In an early group, the percentage of CSF leaks was 6.9%. On the basis of the evaluated causes, as time went by, technical modifications evolved. They consisted of 1) the total conservation of the fascioperiosteal flap, 2) obliteration of all petrosal cells possibly communicating with the middle ear, 3) removing the incus in a correct way, 4) closing the attic with periosteum, 5) obliterating the surgical cavity, leaving strips of abdominal fat with their medial ends inside the cerebellopontine angle, 6) suturing the musculo-periosteal layer in a correct way, and 7) fixing the skin flap to the underlying surface. The application of these modifications resulted in a total absence of CSF leaks in 200 consecutive patients thereafter. Also, no cases of meningitis were encountered.To our knowledge, this is the first series of 200 consecutive vestibular schwannoma patients operated by means of the enlarged TLA without a single CSF leak. When the appropriate measures are taken, the number of CSF leaks after removing tumors through the enlarged TLA must and can be reduced to 0.

Intratemporal carotid artery aneurysms are rare lesions, with only 54 cases reported in the literature. Their most common symptoms are pulsatile tinnitus, hearing loss and signs of Eustachian tube obstruction. In case of aneurysm rupture, bleeding may be so profuse as to require emergency legation of the common carotid in the neck. Arteriography is the diagnostic gold standard for this disorder. Successful treatment usually involves selective aneurysm embolization or carotid closure with detachable balloons. The authors report a new case of intratemporal carotid artery aneurysm previously treated with selective embolization. To avoid the risk of aneurysm recanalization and/or infection through the external auditory canal, middle ear obliteration and blind-sac closure of the external canal were performed in this case.

Since the abrupt drop in the mortality rate as a result of the introduction of microsurgical dissection techniques in the treatment of acoustic neuromas, surgeons have concentrated their efforts on preserving hearing and facial nerve function. In the translabyrinthine approach, identification of the facial nerve at the fundus of the internal auditory canal is an important step for subsequent dissection. However, the identification techniques available to date carry with them some potential risk of facial nerve injury when performed by inexperienced surgeons. In addition, they are time-consuming procedures. The authors present an alternative method for identification of the facial nerve at the fundus of the internal auditory canal during the translabyrinthine approach. The superior ampullary nerve is interrupted at the superior cribrosa area where it is not in intimate relationship with the facial nerve. Medial reflection of the superior ampullary nerve and the superior vestibular nerve facilitates identification of the facial nerve and preparation of a vestibulo-facial dissection plane.

Simultaneous occurrence of a vestibular schwannoma and a glomus tympanicum tumor has been reported only once in the international literature. The authors present a second case: a 72-year-old woman having a glomus tympanicum tumor and an ipsilateral lesion confined to the internal auditory canal, radiologically diagnosed as an acoustic neuroma. Due to the patient's age, symptoms, hearing threshold and the small size of both tumors the decision was made not to perform surgery. The patient will be regularly followed-up through computerized tomography and magnetic resonance imaging.

Cerebrospinal fluid (CSF) leak is one of the most dangerous complications that can arise in cases of acoustic neuroma removal. It increases the risk of meningitis, requires longer postoperative recovery and often requires revision surgery. A retrospective analysis was performed on all cases of acoustic neuromas which had undergone translabyrinthine surgery at the Gruppo Otologico, Piacenza, Italy, between April 1987 and December 1997, in the aim of finding the causes of postoperative CSF leaks. The causes found were high pneumatization of the temporal bone and improper execution of some surgical steps. The technique has presently been modified on the basis of the experience gained from cases of CSF leaks. By scrupulously applying these modifications, from July 1994 to December 1997, a total of 160 patients were consecutively treated using the translabyrinthine approach without a single case of postoperative CSF leak. Routine use of this modified technique can and must lower the percentage of CSF leaks after a translabyrinthine surgery to nearly 0%.

Thanks to ongoing development in microsurgical techniques to treat the skull base some clivus lesions, considered inoperable until a few years ago, can now be removed with relatively low mortality and morbidity. The approaches available for the treatment of lesions in this anatomical area can be broken down into anterior and lateral. The latter offer the surgeon several important advantages such as better control over the main vascular structures and the possibility of opening the intradural space without coming into communication with the pharynx. By virtue of their extreme versatility, the lateral approaches may be used in combination in a single operation or can be performed as staged procedures. Each of the lateral routes, however, has its own advantages and drawbacks. These are presented during a brief description of each technique. The main factor in selection of approach is the anatomical limits of the approach itself. Generally speaking, the largest surgical field is offered by the most destructive approaches. Although they do cause such deficits as unilateral hearing loss, these approaches permit greatly improved control over the vital structures. Nevertheless, when such deficits exist prior to surgery, the morbidity of such approaches is negligible. The histological nature of the disease, the variable relationships with the dura, the main neurovascular structures and other factors should all be considered when deciding how to manage each case. The surgeon must, however, have the range of skills required to perform the diversity of approaches to the lateral skull base so as to provide the patient with the best possible care.

The Bondy technique is a particular radical, yet conservative, treatment where the intact tympanic-ossicular system is preserved during the operation. This technique was initially introduced by Gustave Bondy in 1910 and has been used at the authors' center since December 1983 with a few modifications. In the twelve years from December 1983 to December 1995 69 cases (66 patients) were treated with this technique: 5.6% of all chronic cholesteatomatose otitis surgically treated during that period. The following indications were applied: purely epitymapnic cholesteatoma, average transmission gap equal to or lower than 25 dB and intact bone chain. During the follow-up no signs of recurrent cholestatoma were found. The average post-operative transmission gap was greater than 25 dB in only 5 of the 54 cases with at least one year of follow-up. When used in selected cases, the modified Bondy technique can be considered an excellent option in the treatment of epitympanic cholesteatoma, making it possible to maintain the good pre-operative hearing without requiring a second operation.

We describe the statistical behavior of anisotropic crystalline membranes. In particular we give the phase diagram and critical exponents for phantom membranes and discuss the generalization to self-avoiding membranes., Comment: LATTICE98(surfaces) 5 pages, 4 Postscript figures

We discuss how to characterize the behavior of a chaotic dynamical system depending on a parameter that varies periodically in time. In particular, we study the predictability time, the correlations and the mean responses, by defining a local--in--time version of these quantities. In systems where the time scale related to the time periodic variation of the parameter is much larger than the ``internal'' time scale, one has that the local quantities strongly depend on the phase of the cycle. In this case, the standard global quantities can give misleading information., 15 pages, Revtex 2.0, 8 figures, included. All files packed with uufiles

We present 44 cases of congenital cholesteatoma of the middle ear. Twenty-one patients had a cholesteatoma located in the posterosuperior mesotympanum. This finding was in complete contrast to the commonly reported anterosuperior location, seen in only 2 cases in our study. The remaining 21 patients had a cholesteatoma involving either the entire mesotympanum and/or epitympanum. The posteriorly located congenital cholesteatoma might represent a completely different entity and originate from epithelial cell debris trapped in the posterior mesotympanum during development of the temporal bone. All but one patient were treated with a closed tympanoplasty. Eight patients underwent single stage surgery. A preplanned second stage procedure was performed in 33 patients, while 3 are presently awaiting the second stage. Residual disease was seen in 19 patients (57%) who had undergone second stage surgery. No patient has had recurrent disease this far. Thirty-eight patients (85%) had a preoperative air bone gap of 30 dB or more. Of the 33 patients evaluated for hearing results, 16 (48%) had a postoperative gap within 10 dB.

A one-dimensional chain of sporadic maps with asymmetric nearest neighbour couplings is numerically studied. It is shown that in the region of strong asymmetry the system becomes spatially fully synchronized, even in the thermodinamic limit, while the Lyapunov exponent is zero. For weak asymmetry the synchronization is no more complete, and the Lyapunov exponent becomes positive. In addition one has a clear relation between temporal and spatial chaos, {\it i.e.}: a positive effective Lyapunov exponent corresponds to a lack of synchronization and {\it vice versa}, 9 pages + 3 figures (postscript appended uuencoded tar), IOP style (appended uuencoded compress)

Middle ear reconstruction using the closed technique for the purpose of rehabilitating radical cavities includes all the surgical steps necessary to perform a combined approach tympanoplasty, both with respect to eradication of the disease and to reconstruction. The only point of difference is the total reconstruction of the posterior wall, which moreover constitutes the essential step. At present we perform posterior wall reconstruction by means of a coastal cartilage allograft, inserted into two grooves in the bone and firmly stabilized by fibrin glue. The operation, in 90% of cases, is performed in more than one stage.

We study the long time behaviour of the transient before the collapse on the periodic attractors of a discrete deterministic asymmetric neural networks model. The system has a finite number of possible states so it is not possible to use the term chaos in the usual sense of sensitive dependence on the initial condition. Nevertheless, at varying the asymmetry parameter, $k$, one observes a transition from ordered motion (i.e. short transients and short periods on the attractors) to a ``complex'' temporal behaviour. This transition takes place for the same value $k_{\rm c}$ at which one has a change for the mean transient length from a power law in the size of the system ($N$) to an exponential law in $N$. The ``complex'' behaviour during the transient shows strong analogies with the chaotic behaviour: decay of temporal correlations, positive Shannon entropy, non-constant Renyi entropies of different orders. Moreover the transition is very similar to that one for the intermittent transition in chaotic systems: scaling law for the Shannon entropy and strong fluctuations of the ``effective Shannon entropy'' along the transient, for $k > k_{\rm c}$., 18 pages + 6 figures, TeX dialect: Plain TeX + IOP macros (included)

The psychiatric observations of female adepts and nuns of Christian monastic congregations, seen as in- or outpatients of a mental hospital of an order, are reported, mainly focussing on schizophrenic and schizophreniform psychoses and severe personality disorders. The patient statistics and sketches of psychopathology and the dynamics of the disorders are presented. The selection process for adepts for the monastic profession and the need for education of the responsible leaders in psychological, psychotherapeutic and psychiatric issues are considered.

In this letter we study chaotic dynamical properties of an asymmetrically coupled one-dimensional chain of maps. We discuss the existence of coherent regions in terms of the presence of defects along the chain. We find out that temporal chaos is instantaneously localized around one single defect and that the tangent vector jumps from one defect to another in an apparently random way. We quantitatively measure the localization properties by defining an entropy-like function in the space of tangent vectors., Comment: 9 pages + 4 figures TeX dialect: Plain TeX + IOP macros (included)

We discuss how the spatial intermittency of energy dissipation in 3D fully developed turbulence affects the small-scale statistics of passive scalars. We relate the passive-scalar behaviour to the diffusion properties of particle pairs in turbulent fluids. We thus find the intermittency correction to the -5/3 Obukhov-Corrsin law for the power spectrum of a passive scalar at wavenumber k where molecular diffusion and viscosity play a negligible role (inertial convective subrange). This correction is positive at difference with the negative correction to the -5/3 Kolmogorov law for the energy spectrum. We finally show that the structure functions of passive scalars have scaling exponents linear in the moment order, even in the framework of multifractal models.

Granular cell tumor of the larynx is a rare benign lesion. The Authors present a literature survey and report a case observed in the E.N.T. Institute of Parma University. The patient was a 22 year-old woman, smoker, whose right vocal cord was affected. Hoarseness represented the only symptom. The tumor was removed by the microsurgical method and histologically examined.

Solving the Langevin equation, describing the approach to equilibrium of two gauge systems at different temperature, numerically, we are able to measure plaquette-plaquette correlation functions at distances 0, 1, 2, 3, 4 on an 8 4 lattice. We estimate the glueball mass to be (2.72 ± 0.20)√ σ .

We study the convection of magnetic fields in the presence of Lagrangian chaos, i.e. when nearby fluid elements diverge exponentially in time. We show that the magnetic field is of a multifractal nature as a consequence of the spatial fluctuations in the exponential growth of the field. We provide numerical and theoretical evidence that the magnetic fields can concentrate in small domains of a fluid with weak Lagrangian chaos. Moreover, these properties are relevant also for the study of the case of small but nonzero magnetic diffusivity.

We extract the lowest glueball mass by studying a suitable response function of an SU(3) pure lattice gauge theory. Our estimate is mg = (305±55) ΛL. We do not find finite size effects at β=6.0 for lattice sizes from 53 × 10 to 73 × 10.

The transition region of Z 2 lattice gauge theory is investigated by inverting the strong coupling series of the average plaquette energy E P ( J ). We find a clear evidence for a first-order transition and the existence of a metastable phase. In the U(1) case we confirm a second-order phase transition even if there is a little discrepancy on the critical point position as indicated by Monte Carlo simulations.

We present the results of a Monte Carlo simulation for a lattice action improved a la Symanzik. The results seem to give a faster approach of the lattice physics to its continuum limit.

We present a new method for calculating block renormalized couplings by Monte Carlo renormalization group. This method has several advantages with respect to the existing ones and can be applied for any value of the coupling constants. A preliminary numerical study of the 2-dimensional O(3) non linear σ-model is also presented.

We have computed the first non-universal term of the β function for the non-linear σ model regularized on a lattice. This fixes the leading analytic corrections to the universal scaling behaviour near the UV fixed point T = 0. The corrections turn out to be too small to explain the deviations from the renormalization group behaviour observed in Monte Carlo simulations.

A recent Monte Carlo simulation showing a sharp peak versus β in the specific heat for an SU(2) lattice gauge theory is compared with the high temperature expansion. An interpretation based on complex β-plane singularities is proposed.

Using a Monte Carlo method to measure the correlation functions of different quantities, the mass spectrum of the glue-ball is investigated for an SU(2) gauge model in an 8 4 lattice.

The environment of membrane-bound proteins has been investigated by measuring the fluorescence of intrinsic tryptophans in intact bovine heart mitochondria, in lipid-depleted mitochondria, and in reconstituted mitochondria. Lipid depletion induces a strong decrease of fluorescence intensity, probably as the result of extraction of peripheral proteins by the solvents used. Comparison of lipid-depleted and lipid-reconstituted mitochondria shows a higher fluorescence in the lipid-depleted membranes; in an Arrhenius plot the fluorescence intensity shows two breaks in the lipid-depleted membranes, but no break in the reconstituted ones. Butanol has little effect on fluorescence intensity of intact mitochondria. The results are compatible with a constant lipid environment of integral proteins which is not modified by either temperature or organic solvents.

We have studied lymphocyte membrane from 7 patients with Duchenne Muscular Dystrophy (DMD) and 8 normal controls using fluorescence polarization of 1,6-diphenyl-hexatriene (DPH). The microviscosity of lymphocytes membrane is significatively higher in DMD patients than in normal controls. Our results support the hypothesis of a generalized membrane defect in Duchenne Muscular Dystrophy.