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Inositol and its derivates are catching interest in metabolism since taking part in several physiological processes, including endocrine modulation. Through several mechanisms mostly mediated by insulin signaling, these compounds regulate the activities of several hormones and are essential in oocytes maturation. It is interesting to point out the contribution of an inositol deficiency in the development of several diseases, mainly in the metabolic and endocrine setting. Inositols derive from both diet and endogenous production; among causes of inositol deficiency reduced dietary intake, increased catabolism and/or excretion, decreased biosynthesis, inhibition of gut and cellular uptake and altered microbiota could be considered. Mounting direct and indirect evidence suggests that the two main isoforms (Myo-inositol-inositol, D-chiro-inositol) are implied in glycemic and lipidic metabolism and supplementation yield a beneficial effect on these parameters without hazards for health. Moreover, they have a role in polycystic ovary syndrome, acting as insulin-sensitizing agents and free radical scavengers, helping to regulate metabolism and promoting ovulation. The aim of this narrative review is to discuss the role of inositols in metabolic function disorders paying attention to whether these compounds could be efficacious and safe as a therapeutic agent with a focus on dietary intake and the role of gut microbiota.

Aim. To evaluate clinical characteristics and perinatal outcomes in a heterogeneous population of Caucasians born in Italy and High Migration Pressure Countries (HMPC) women with GDM living in Piedmont, North Italy. Methods. We retrospectively analyzed data from 586 women referring to our unit (2015–2020). Epidemiological (age and country of origin) and clinical-metabolic features (height, weight, family history of DM, parity, previous history of GDM, OGTT results, and GDM treatment) were collected. The database of certificates of care at delivery was consulted in relation to neonatal/maternal complications (rates of caesarean sections, APGAR score, fetal malformations, and neonatal anthropometry). Results. 43.2% of women came from HMPC; they were younger p

Abstract Metal nanoclusters featuring tunable luminescence and high biocompatibility are receiving attention as fluorescent markers for cellular imaging. The recently discovered ability of gold clusters to scavenge cytotoxic reactive oxygen species (ROS) from the intracellular environment extends their applicability to biomedical theranostics and provides a novel platform for realizing multifunctional luminescent probes with engineered anti-cytotoxic activity for applications in bio-diagnostics and conceivably cellular therapy. This goal could be achieved by using clusters of strongly reactive metals such as silver, provided that strategies are found to enhance their luminescence while simultaneously enabling direct interaction between the metal atoms and the chemical surroundings. In this work, we demonstrate a synergic approach for realizing multifunctional metal clusters combining enhanced luminescence with strong and lasting ROS scavenging activity, based on the fabrication and in situ protection of Ag nanoclusters with a supramolecular mantle of thiolated-Au atoms (Ag/Au-t). Confocal imaging and viability measurements highlight the biocompatibility of Ag/Au-t and their suitability as fluorescent bio-markers. ROS concentration tests reveal the remarkable scavenging activity of Ag-based clusters. Proliferation tests of cells in artificially stressed culture conditions point out their prolonged anti-cytotoxic effect with respect to gold systems, ensuring positive cell proliferation rates even for long incubation time.

By means of time- and angle-resolved photoelectron spectroscopy, we give evidence of a remarkable reduction of the Fermi velocity of out-of-equilibrium Dirac bands in the quasi-two-dimensional semimetal BaNiS_{2}. This effect is accompanied by a nonrigid shift of the bands at the center of the Brillouin zone. Analytical and first-principles calculations indicate that this band renormalization is ascribed to a change in nonlocal electron correlations driven by a photoinduced enhancement of screening properties. Our results are explained by a scaling relation between inverse screening length and electronic temperature that is of general relevance for the description of out-of-equilibrium dynamics and screening effects in all layered Dirac materials.

This article presents the scientific rationale for an ambitious ICDP drilling project to continuously sample Late Cretaceous to modern sediment in four different sedimentary basins that transect the equatorial Amazon of Brazil, from the Andean foreland to the Atlantic Ocean. The goals of this project are to document the evolution of plant biodiversity in the Amazon forests and to relate biotic diversification to changes in the physical environment, including climate, tectonism, and the surface landscape. These goals require long sedimentary records from each of the major sedimentary basins across the heart of the Brazilian Amazon, which can only be obtained by drilling because of the scarcity of Cenozoic outcrops. The proposed drilling will provide the first long, nearly continuous regional records of the Cenozoic history of the forests, their plant diversity, and the associated changes in climate and environment. It also will address fundamental questions about landscape evolution, including the history of Andean uplift and erosion as recorded in Andean foreland basins and the development of west-to-east hydrologic continuity between the Andes, the Amazon lowlands, and the equatorial Atlantic. Because many modern rivers of the Amazon basin flow along the major axes of the old sedimentary basins, we plan to locate drill sites on the margin of large rivers and to access the targeted drill sites by navigation along these rivers.

The control of the electron spin by external means is a key issue for spintronic devices. Using spin- and angle-resolved photoemission spectroscopy (SARPES) with three-dimensional spin detection, we demonstrate operando electrostatic spin manipulation in ferroelectric α-GeTe and multiferroic Ge_{1−x}Mn_{x}Te. We demonstrate for the first time electrostatic spin manipulation in Rashba semiconductors due to ferroelectric polarization reversal. Additionally, we are also able to follow the switching pathway in detail. In multiferroic Ge_{1−x}Mn_{x}Te operando SARPES reveals switching of the perpendicular spin component due to electric-field-induced magnetization reversal. This provides firm evidence of magnetoelectric coupling which opens up functionality with a multitude of spin-switching paths in which the magnetic and electric order parameters are coupled through ferroelastic relaxation paths. This work thus provides a new type of magnetoelectric switching intertwined with Rashba-Zeeman splitting in a multiferroic system.

The basic equations used to study the fluid diffusion in porous media have been set by Fick and Darcy in the mid of the XIXth century but some data on the flow of fluids in rocks exhibit properties which may not be interpreted with the classical theory of propagation of pressure and fluids in porous media (Bell and Nur, 1978; Roeloffs, 1988). Concerning the fluids and the flow, some fluids carry solid particles which may obstruct some of the pores diminishing their size or even closing them, some others may chemically and physically react with the medium enlarging the pores; so permeability changes during time and the flow occurs as if the medium had a memory. In this paper we show with experimental data that the permeability of sand layers may decrease due to rearrangement of the grains and consequent compaction, as already shown qualitatively by Elias and Hajash (1992). We also provide a memory model for diffusion of fluids in porous media which fits well the flux rate observed in five laboratory experiments of diffusion of water in sand. Finally we show that the flux rate variations observed during the experiments are compatible with the compaction of sand, due to the amount of fluid which went through the grains locally, and therefore with the reduction of porosity.

Abstract Background BRCA1:c.5017_5019del (p.His1673del) is a founder variant relatively frequent in Northern Italy. Despite previous suggestion of pathogenicity, variant classification in public databases is still conflicting, needing additional evidence. Methods Maximum likelihood penetrance of breast/ovarian and other cancer types was estimated using full pedigree data from 53 informative Italian families. The effect of the variant on BRCA1‐ABRAXAS1 interaction was assessed using a GFP‐fragment reassembly‐based PPI assay. Results were combined with additional data from multiple sources to classify the variant according to ACMG/AMP classification rules specified for BRCA1/2. Results Variant‐carriers displayed increased risk for ovarian cancer (HR = 33.0, 95% CI = 7.0–155.0; cumulative risk at age 70 = 27.6%, 95% CI = 12.6–40.0%) but not for breast cancer (HR = 0.7, 95% CI = 0.2–2.2). An increased risk of uterine cancer (HR = 8.0, 95% CI = 1.03–61.6) emerged, warranting further evaluation. Likelihood‐ratio in favor of pathogenicity was 98898642.82 under assumption of standard BRCA1 breast and ovarian penetrance, and 104240832.84 after excluding breast cancer diagnoses (based on penetrance results). Functional analysis demonstrated that the variant abrogates the BRCA1‐ABRAXAS1 binding, supporting the PS3 code assignment within the ACMG/AMP rule‐based model. Collectively, these findings allowed to classify the variant as pathogenic. Conclusion Pathogenicity of BRCA1:c.5017_5019del(p.His1673del) has been confirmed; however, breast cancer risk in Italian families is not increased, unlike in families from other countries and in carriers of most BRCA1 pathogenic variants. The knowledge of atypical risk profiles for this and other variants will pave the way for personalized management based on specific genotype.

Distributed order fractional differential equations (Caputo, 1995, 2001; Bagley and Torvik, 2000a,b) were fi rst used in the time domain; they are here considered in the space domain and introduced in the constitutive equation of diffusion. The solution of the classic problems are obtained, with closed form formulae. In general, the Green functions act as low pass fi lters in the frequency domain. The major difference with the case when a single space fractional derivative is present in the constitutive equations of diffusion (Caputo and Plastino, 2002) is that the solutions found here are potentially more fl exible to represent more complex media (Caputo, 2001a). The difference between the space memory medium and that with the time memory is that the former is more fl exible to represent local phenomena while the latter is more fl exible to represent variations in space. Concerning the boundary value problem, the difference with the solution of the classic diffusion medium, in the case when a constant boundary pressure is assigned and in the medium the pressure is initially nil, is that one also needs to assign the fi rst order space derivative at the boundary.

The dielectric parameter, in the generalised Debye form, of all studied substances (Cole and Cole, 1941) contains a rational power of the imaginary frequency which implies that the index of refraction is a multivalued function of the frequency; the same property, concerning the stress strain relation, also applies to anelastic media (Bagley and Torvik, 1983a,b). The multivalued index of refraction implies then that the free modes of dielectric and anelastic media are split into a number of modes which depend on the exponent of the imaginary frequency. In order to estimate if it is possible to observe this splitting, this note computes the parameters appearing in the generalised Debye form of the dielectric parameters of many substances and also the complex anelastic parameter of an anelastic medium. The analysis of the data indicates that, depending on the accuracy of the experimental data, with few exceptions, the splitting is observable.

We present and test in detail with synthetic data a method which may be used to retrieve the parameters describing the induced polarization properties of media which fit the generally accepted frequency dependent formula of Cole and Cole (1941) (CC model). We use time domain data and rigorous formulae obtained from the exact solution of the problem found in a previous note (Caputo, 1996). The observed data considered here are the theoretical responses of the medium to box inputs of given duration in media defined with different parameters; however, as is usually done, only the discharge data are used (Patella >F2F1

Since the dispersion and attenuation properties of dielectric and anelastic media, in the frequency domain, are expressed by similar formulae, as shown experimentally by Cole and Cole (1941) and Bagley and Torvik (1983, 1986) respectively, we note that the same properties may be represented in the time domain by means of an equation of the same form; this is obtained by introducing derivatives of fractional order into the system functions of the media. The Laplace Transforms (LT) of such system functions contain fractional powers of the imaginary frequency and are, therefore, multivalued functions defined in the Riemann Sheets (RS) of the function. We determine the response of the medium (dielectric o anelastic) to a generic signal summing the time domain representation due to the branches of the solutions in the RSs of the LT. It is found that, if the initial conditions are equal in all the RSs, the solution is a sum of two exponentials with complex exponents, if the initial conditions are different in some of the RSs, then a transient for each of those RSs is added to the exponentials. In all cases a monochromatic wave is split into a set of waves with the same frequency and slightly different wavelengths which interfere and disperse. As a consequence a monochromatic electromagnetic wave with frequency around 1 MHz in water has a relevant dispersion and beats generating a tunnel effect. In the atmosphere of the Earth the dispersion of a monochromatic wave with frequency around 1 GHz, like those used in tracking artificial satellites, has a negligible effect on the accuracy of the determination of the position of the satellites and the positioning of the bench marks on the Earth. We also find the split eigenfunctions of the free modes of infinite plates and shells made of dielectric and anelastic media.

The scope of this note is to study a model of induced polarization which fits the usually accepted frequency dependent formula of Cole and Cole, but is more general and allows the time domain observations to retrieve the parameters describing the induced polarization phenomena of the medium. By introducing the memory mechanisms, represented by derivatives of fractional order, in the relation between the electric flux density and the electric field and considering the fractional order differential equation which follows, I solve it with mathematically rigorous and closed formulae and compute the responses to a step function, a box, a set of positive boxes and a set of alternating positive and negative boxes. I also introduce a method which retrieves the parameters describing the medium when comparing the theoretical curves with the observed ones. The responses to these signals also allow to estimate the temporary alteration of the medium when repeated positive (negative) signals are input; the response increases (decreases) in amplitude when the signals are all positive (negative), it decreases when the signals are alternatively positive and negative in agreement with the known attitude of the medium to induced polarization.

Since 1987 multichannel instrumentation has been recording electromagnetic and seismoacoustic emissions in the Amare cave (Gran Sasso í L'Aquila). Equipment detecting RMC (Principality of Monaco) longwave broadcasting (216 kHz) has been operating in the same place. Data collected during this period have pointed out two different phenomena called «quiet» and «perturbed» that characterize the normal behaviour of the cave. On 25 August 1992 an earthquake with M = 3.9 occurred in the Gran Sasso area and on 4 June 1993 an earthquake with M = 4.3 occurred in Umbria, 100 km to north of the Amare cave. Before these earthquakes, electromagnetic, seismoacoustic, and RMC data showed anomalies. Here we present the observed phenomenology and discuss the possibility that the anomalies can be considered precursors of the earthquakes.

The modern constitutive equations of the rheology of analeptic media and of the polarization in dielectric media are discussed in the time and frequency domains. It is seen that the most appropriate form of the constitutive equations of these media is based on the convolution of the stress and strain, and of the electric field and induction respectively, with appropriate functions representing the memory of the medium to previous stress or induction. The most successful memory forma]ism in representing the observed phenomena is that of the derivative of fractional order which allows a variety of problems to be solved by means of the Laplace Trans- form. The consequent index of refraction, generally, is a set valued function which implies that a monochromatic wave generated in the medium is split into a set of waves with the same frequency but different wavelength which interfere and have a quasi periodically varying amplitude. The eigenfunctions of these media, associated to the ordinarily used principal values of the index of retraction, are split and so are the tree modes. The fatigue of anelastic media is studied using the new constitutive equations containing fractional derivatives; a phenomenological method is introduced to compute the number of cycles which gives fatigue for a strain or stress with given amplitude and frequency. The number of cycles which may cause fatigue is proportional to the amplitude and frequency of the applied strain or stress, or inversely proportional to the rate of stress or strain. A criterion is also established to see whether an applied cyclic stress or strain may cause fatigue. This criterion is tested with experimental data on steel and rocks verifying that, in general, it is consistent with the data although thc data are not always in the linear range. It is tentatively seen that fatigue docs not seem one of the causes of the release of the elastic energy stored in the Earth.

In this paper we model the geometry of a seismic source as a dislocation occurring on an elemental flat fault in an arbitrary direction with respect to the fault plane. This implies the use of a fourth parameter in addition to the three usual ones describing a simple double couple mechanism. We applied the radiation pattern obtained from the theory to a computer code written for the inversion of the observation data (amplitudes and polarities of the first onsets recorded by a network of stations). It allows the determination of the fault mechanism gener- alized in the above mentioned way. The computer code was verified on synthetic data and then applied to real data recorded by the seismic network operated by the Ente Nazionale per l'Energia Elettrica (ENEL), monitoring the geothermal field of Larderello. The experimental data show that for some events the source mechanism exhibits a significant dipolar component. However, due to the high standard deviation of the amplitude data, F-test applied to the results of the analysis shows that only for two events the confidence level for the general- ized model exceeds 90%.

n 1990, some instrumentation was set up in the Amare cave (southern slope of the Gran Sasso chain, L'Aquila) in order to pick up electric signals ranging from 0.3 to 300 kHz, magnetic signals from 0.3 to 30 kHz and seismoacoustic signals by means of three geophones with natural frequencies of 0.3 kHz, 25 kHz and 150 kHz. Data are recorded every ten minutes on a solid state memory. The analysis of the data allows us to establish the existence of electromagnetic fields of distant origin connected with broadcastings and with tropical lightning activity and the discontinuous presence of local electric and magnetic signals, coupled with seismoacoustic ones, connected with weather events. A qualitative explanation of these near fields is given.

El análisis estadístico de caídas de esfuerzo, p, de 5 grupos de temblores en California y México confirma que la distribución de densidad de p es proporcional a p-l+α(α

With different approximate methods are estimated thevalues of the area of the fault, of the dislocation, of the stress drop and ofthe seismic moment of the Friuli earthquake of May 6th, 1976. Some considerationsfollow on the possibility to forecast the earthquake and on itsrelation to the subsequent event of September 11th.

The estimation of seismic risk is made for three types of objects in the central Italy, considering three kinds of models: 1) - A(2I,g): the intensity of the Poisson's flow of earthquakes, M being the magnitude, g the liypocentre. 2) - I(g,g,M): giving the distribution on the surface for a single earthquake (g,M), g being the epicentre. 3) - x(g,I): giving the effect x of the shakings of intensity / , g being the position of the object. For actual decision-making additional computations may be necessary in order to estimate how our results are influenced by the errors in these models. However practical decision can be made on the basis of these data, because the experience shows that normally results are exagerated.

The dispersion of the phase velocities of the surface Rayleighwaves on the path between the station pair Torino-L'Aquila in theApennines has been observed with long period seismic stations for twinearthquakes.The inversion was provided by the "Hedgehog" program of non-linearinversion analysis.The interpretation supports the notion that in the Apennines low-velocitymaterial in the mantle is found within a few km of the Moho and maylie immediately below the Moho; however the alternative model of a highvelocitylid and very low-velocity channel cannot be completely rejected.

A method is described that makes possible the identification of the independent seismic units of a given area (Caputo and Postpischl, 1973 b). The seismic information is treated as a bidimensional signal disturbed by a certain background noise. The filtering of this noise makes it possible to delineate the seismic areas objectively. An indirect check on the method was made by estimating with respect to the various regions identified the a and /J parameters of the law Ny = a e~Py which gives the number of earthquakes with magnitude (intensity) greater than or equal to y.

RIASSUNTO - 11 modello proposto da Caputo per la statistica dei parametridei terremoti in una zona sismica viene confrontato con i dati disponibili perla California. Tali dati provengono dal lavoro di Thatcher e Hanks e da quellidi Tucker e Brune. In essi sono riportate le serie di parametri M,M0 , l e / posservati sperimentalmente. Per entrambe le serie di parametri vengono calcolatele distribuzioni statistiche e i risultali sono confrontati fra loro per mezzo dellerelazioni imposte dalla teoria. I risultati, compatibilmente con le incertezzesperimentali e la scarsezza dei campioni adoperati, sembrano confermare lateoria e permettono di valutare la distribuzione per i parametri delle faglie chedanno origine ai terremoti nella California.

In recent years theoretical seismology lias introducedsome formulae relating the magnitude and the seismic moment of earthquakesto the size of the fault and the stress drop which generated theearthquake.In the present paper we introduce a model for the statistics of theearthquakes based on these formulae. The model gives formulae whichshow internal consistency and are also confirmed by observations.For intermediate magnitudes the formulae reproduce also the trendof linearity of the statistics of magnitude and moment observed in all theseismic regions of the world. This linear trend changes into a curve withincreasing slope for large magnitudes and moment.When a catalogue of the magnitudes and/or the seismic moment ofthe earthquakes of a seismic region is available, the model allows to estimatethe maximum magnitude possible in the region.

We present a study of a group of long period waves excited by theearthquakes of Friuli (Italy) in 1976 and recorded between longitudinaland transverse body waves by Long-period seismographs at epicentraldistances up to about 3 000 Km. The spectral analysis has permitted usto determine periods of the main phases which make up the wave group.In regard to the longer period phase, which appears first in the recordings,the velocity obtained by the dromochrones equals 8.4 Km/s. The groupvelocity is instead 7.4 Km/s. Such phases have been considered as beinglongitudinal channel waves in the astenosphere. Such hypothesis explainsthe inconsistencies which had appeared in previous studies on channelwaves in the astenosphere.

Under the hypothesis of hydrostatic equilibrium the planets of the solar system are represented on the plane (J"2, w2 a?/MG) (J2 = second term of the gravitational potential, w = rotation rate of the planet, a — equatorial radius, M — mass of the planet, G = gravitational constant). Since the points representing the planets lie on a straight line it is possible to obtain informations on the giration moment and the moment of inertia of Uranus and Pluto.

SUMMARY - Most of strong earthquakes in Italy seem to be preceded byanomalous swarms of weaker shocks. Similiar precursor was described byProzoroff and al (1972) for Central Asia. Most often the swarms occur nearthe same lineament, as the strong earthquake which follow them.

This paper is a contribution to t h e study of the problemof subsidence in the Po delta and in t h e Venetian lagoon. We have comparedt h e d a t a supplied by tide gauges in Trieste, Venice and Porto Corsini (Fig. 1)during t h e period 1896-1966, and in Genoa in t h e period 1894-1966. Althoughd a t a were recorded in slightly different periods, these periods are sufficientlyoverlapping to allow for a significant statistical comparison. We note t h a t themovement of t h e annual mean sea level in Genoa and Trieste is greatly differentf r om t h a t of Porto Corsini and Venice and, in order to separate the componentdue to eustatic effect f r om any possible movement of the coast, we calculatet h e polynomial coefficients, t h a t best fit t h e real movements. Approximatingpolinomials are of first degree for Genoa and Trieste and of seconddegree for Porto Corsini and Venice. We have evaluate the coefficients ofcrosscorrelation firstly on original d a t a and then subtracting f r om original d a tathe best fit polinomials. The correlation is very significant and the trend issimilar in Trieste and Genoa. The power spectrum analysis with the directFourier's method show long periods wich are shared by tide gauges. Weconclude estimating 1,35 mm/year the increase of the mean sea level for t heeustatic effect in the Mediterranean 3,9 mm/year the subsidence in PortoCorsini and 1,4 mm/year the subsidence in Venice.

The decay of the amplitude of the free modes of theEarth is a potential source of information on the mechanism of dissipationof the elastic energy of the Earth.However there are serious difficulties in the interpretation of the decay;they are caused by several facts. One is the limited length of the significantpart of the record which prohibits to identify the splitting of all the modescaused by the Earth rotation and also to follow the pattern in its rotation;another reason is the coupling between modes, caused by the inhomogenitiesand the flattening of the Earth, which can transfer energy from one modeto another. The results available are therefore very few and of poor accuracy.In order to seek new information on the mechanism of dissipation ofthe elastic energy we solve a generalized form of the equation of elastodynamicin which we have introduced some unspecified operators to representthe dissipation of the elastic energy. By confronting these operators withthe observations we would hope to find informations on the mechanismof dissipation. Unfortunately the laws of variation of Q with frequency,found by various authors who were using different observations, are not inagreement and are very uncertain. Therefore we can only estimate theaverage values of the parameters of the supposed mechanisms of dissipation.We analyze also the dissipation of energy due to viscous frictions atthe core mantle boundary. This dissipation would be negligible even forviscosities of the core up to 1010 poise

Ve (Ievelop Oll e(lIlation of statc for the atulII based Olithe elasticity formalism whirh cxtendR, (he vali(lit.y uf the Thomils-IIllodel to pressures of geoph:rsical illterest. The model is (')le('kcd withsho('k Waves (lata, with the Bireh-~rurnaghan f'qllations und \"ith the Earth's('onl e(juation of sta(.e.

We computed the values of flattening / of the equipotentialellipsoid of the Earth's field and of coefficients of the normal gravity,according to the Earth's parameters adopted by the International Unionof Geodesy and Geophysics at its General Assembly of 1967 taking intoaccount the mass of atmosphere and using the closed formulae of the Pizzetti-Somigliana theory that appear in: M. Caputo " The Gravity Field ofthe Earth from classical and modern Methods", Academic Press, 1967.

Laboratory experiments and field observations indicatethat tlie Q of many non ferromagnetic inorganic solids is almost frequencyindependent in the range 10' to 10~2 cps; although no single substance hasbeen investigated over the entire frequency spectrum. One of the purposesof this investigation is to find the analytic expression of a linear dissipativemechanism whose Q is almost frequency independent over large frequencyranges. This will be obtained by introducing fractional derivatives in thestress strain relation.Since the aim of this research is to also contribute to elucidating thedissipating mechanism in the earth free modes, we shall treat the cases ofdissipation in the free purely torsional modes of a shell and the purelyradial vibration of a solid sphere.The theory is checked with the new values determined for the Q ofthe spheroidal free modes of the earth in the range between 10 and 5 minutesintegrated with the Q of the Railegh waves in the range between 5 and 0.6minutes.Another check of the theory is made with the experimental valuesof the Q of the longitudinal waves in an alluminimi rod, in the range between10-5 and 10-3 seconds.In both clicks the theory represents the observed phenomena verysatisfactory.

Qucst.a riccrca è un t.entatiyo di spicgart' l'esistenzaaelle righe usservat.e nello spettro delle oseillazioni libere (Iella 'l'erra llUnident.ifica bili cun righc preyi~t.e per i mOt1elli più attendibili.Prima si stUilia il eomport.ament.u nun lineare degli strument.i dimisura e la loro intt'razione (~ol fenumeno; e si vede che quest.a illteraziullenon potrebbe causare le righe anomale ma, al più un aliargalllellt.o dellerighe osservate. Pui si st.uùiano i fenomeni non lineari nel easo delle oscil·laziuni pU!"alllellt.e rallirui e si vede che per determinare i paramet ri ela.~t.i(·iche (~ar atterizzallo il eompurt.alllellt.u ILOIL lilleare ùel campo, Rono neeessariemolte più informazioni ehe per i parametri lilleari; si suggeriscc inoltrc ilImetodo per il calcolo di questi paramet ri eli ÌlLfilLe si lliscut.e la possibilitàdi osservare quest.i Ienomelli nelle oscillazioni libere della Terra.