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Parasitological examination of a stranded hawksbill turtle (Eretmochelys imbricata) from Pacific coast of Costa Rica revealed the presence of a rich digenean fauna including Carettacola stunkardi (Spi- rorchiidae), Enodiotrema reductum (Plagiorchiidae), Cricocephalus albus, Adenogaster serialis, Epi- bathra crassa, Pleurogonius lobatus, P. trigonocephalus, P. linearis, and Pyelosomum posterorchis (Pronocephalidae). All helminths except C. albus and P. lobatus represent new geographical records for Costa Rica. Carettacola stunkardi is reported for first time in an Eastern Pacific hawksbill turtle and its pathological changes are here described. Histologically, nodular lesions on the serosal sur- face of intestine revealed a mixed infiltrate of heterophils, lymphocytes, and histiocytes within necrotic debris. Granulomas with spirorchiid eggs were observed El examen parasitológico de una tortuga carey (Eretmochelys imbricata) varada en la costa del Pacífico de Costa Rica reveló la presencia de una rica fauna digénica que incluye Carettacola stunkardi (Spi- rorchiidae), Enodiotrema reductum (Plagiorchiidae), Cricocephalus albus, Adenogaster serialis, Epi- bathra crassa, Pleurogonius lobatus, P. trigonocephalus, P. linearis y Pyelosomum posterorchis (Pronocephalidae). Todos los helmintos, excepto C. albus y P. lobatus, representan nuevos registros geográficos para Costa Rica. Carettacola stunkardi se reporta por primera vez en una tortuga carey del Pacífico Oriental y se describen aquí sus cambios patológicos. Histológicamente, las lesiones nodulares en la cara serosa de la serosa del intestino revelaron un infiltrado mixto de heterófilos, linfocitos e histiocitos dentro de restos necróticos. Se observaron granulomas con huevos de espirilo Escuela de Medicina Veterinaria

This paper proposes a torque controller for dynamic visual servoing taking into account the time delay resulting from the image processing and the frame rate of the camera. The method identifies the sources of intrinsic instability and reacts to their destabilizing effect using the passivity criteria. The behavior of the proposed controller is evaluated in a simulation study for the scenario of approaching the grasping frame on a moving target satellite by a 7-DoF manipulator mounted on a free-floating base as part of an on-orbit servicing manoeuvre. The results show the increase in performance while maintaining stability.

Several biological organisms, from some sea shells to butterflies, exhibit sophisticated optical systems, which have been developed during the evolution of each species. The diatoms are microscopic algae enclosed between two valves of hydrated amorphous silica. These intricate structures, called frustules, show quite symmetric patterns of micrometric and nanometric pores. Their strong similarity with man-made objects suggests to exploit the optical properties of the frustules in light guiding and optical transducing. We have found very interesting results, both from the experimental and numerical points of view. Several biological organisms, from some sea shells to butterflies, exhibit sophisticated optical systems, which have been developed during the evolution of each species. The diatoms are microscopic algae enclosed between two valves of hydrated amorphous silica. These intricate structures, called frustules, show quite symmetric patterns of micrometric and nanometric pores. Their strong similarity with man-made objects suggests to exploit the optical properties of the frustules in light guiding and optical transducing. We have found very interesting results, both from the experimental and numerical points of view. © 2008 Elsevier Ltd. All rights reserved.

Diatoms are monocellular micro-algae provided with external valves, the frustules, made of amorphous hydrated silica. Frustules present patterns of regular arrays of holes, the areolae, characterized by sub-micrometric dimensions. Frustules from centric diatoms are characterized by a radial disposition of areolae and exhibit several optical properties, such as photoluminescence, lens-like behavior and, in general, photonic-crystal-like behavior as long as confinement of electromagnetic field is concerned. In particular, intrinsic photoluminescence from frustules is strongly influenced by the surrounding atmosphere: on exposure to gases, the induced luminescence changes both in the optical intensity and peaks positions. To give specificity against a target analyte, a key feature for an optical sensor, a biomolecular probe, which naturally recognizes its ligand, can be covalently linked to the diatom surface. We explored the photoluminescence emission properties of frustules of Coscinodiscus wailesii centric species, characterized by a diameter of about 100-200 μm, on exposure to different vapours and in presence of specific bioprobes interacting with target analytes. Very high sensitivities have been observed due to the characteristic morphology of diatoms shells. Particular attention has been devoted to the emission properties of single frustules. Diatoms are monocellular micro-algae provided with external valves, the frustules, made of amorphous hydrated silica. Frustules present patterns of regular arrays of holes, the areolae, characterized by sub-micrometric dimensions. Frustules from centric diatoms are characterized by a radial disposition of areolae and exhibit several optical properties, such as photoluminescence, lens-like behavior and, in general, photonic-crystal-like behavior as long as confinement of electromagnetic field is concerned. In particular, intrinsic photoluminescence from frustules is strongly influenced by the surrounding atmosphere: on exposure to gases, the induced luminescence changes both in the optical intensity and peaks positions. To give specificity against a target analyte, a key feature for an optical sensor, a biomolecular probe, which naturally recognizes its ligand, can be covalently linked to the diatom surface.We explored the photoluminescence emission properties of frustules of Coscinodiscus wailesii centric species, characterized by a diameter of about 100-200 mu m, on exposure to different vapours and in presence of specific bioprobes interacting with target analytes. Very high sensitivities have been observed due to the characteristic morphology of diatoms shells. Particular attention has been devoted to the emission properties of single frustules.

Mechanical properties of concrete can consistently affect the seismic performance of RC buildings. A proper determination of the concrete strength is therefore essential for a reliable modeling of the structure. The current European Technical Code, Eurocode 8, provides a criterion for the strength assumption related to the knowledge level of the structure, which does not take into account the variability of the strength. If the concrete strength is affected by a large variability, the conventional value suggested by Eurocode 8 can be not conservative, since it does not consider the increase in the demand due to a not homogeneous strength distribution and the reduced capacity of the weaker members. In this paper the concrete strength variability is investigated as a source of in-plan and in-elevation irregularity. The effects of the strength variability on the seismic response and performance are evaluated on a case study, that is a 4-storeys 3D framed building. The seismic response of the case study has been represented by performing a nonlinear static analysis, while the seismic performance has been measured in terms of chord rotation. Results obtained from the analysis have been compared with the Eurocode 8 previsions.

The correct estimation of the compressive concrete strength plays a key role in the evaluation of the structural performance of existing RC buildings. Both Italian (NTC 2008) and European (EC8) Standards define different levels of knowledge according to the number of tests carried out on a building. They indicate a reduced value to assume in the analysis, defined as the mean value of the compressive strength, divided by a confidence factor. However, such a procedure completely neglects the dispersion of the test data, as represented by the high values of the coefficient of variation. Instead, this aspect is treated by FEMA 356 where a limit to the coefficient of variation was introduced. In this paper, with reference to a significant number of existing buildings located in Tuscany, the coefficient of variation (cov) of concrete strength is evaluated and the frequency of high cov values is determined. The dispersion of compressive strength, obtained by SonReb method, using correlation curves calibrated ad hoc on single building, shows that increasing the number of data for each building the coefficient of variation does not necessary decrease. Moreover, the strength value considered by EC8 in the analysis for a single building, i.e. the mean value of compressive strength, is often not conservative, while the approach provided by FEMA 356 is safer since it dependent on the cov itself.

It is known that a properly arranged distribution of nanoholes on a metallic slab is able to produce, in far field conditions, light confinement at sub-diffraction and even sub-wavelength scale. The same effect can also be implemented by the use of Optical Eigenmode (OEi) technique. In this case, a spatial light modulator (SLM) encodes phase and amplitudes of N probe beams whose interference is able to lead to sub-wavelength confinement of light focused by an objective. The OEi technique has been already used in a wide range of applications, such as photoporation, confocal imaging, and coherent control of plasmonic nanoantennas. Here, we describe the application of OEi technique to a single valve of a marine diatom. Diatoms are ubiquitous monocellular algae provided with an external cell wall, the frustule, made of hydrated porous silica which play an active role in efficient light collection and confinement for photosynthesis. Every frustule is made of two valves interconnected by a lateral girdle band. We show that, applying OEi illumination to a single diatom valve, we can achieve unprecedented sub-diffractive focusing for the transmitted light.

We present the application of a preconditioned nonlinear conjugate gradients (PC-NLCG) optimizer to a common-image-point (CIP) seismic tomography. The new solver operates in our simultaneous joint inversion (SJI) framework, automatically being available for any possible single-domain inversion or SJI configuration with other seismic or non-seismic datasets. In all the tests we carried out the new PC-NLCG has always outperformed the standard NLCG. We show an example of performance improvement using data from a CIP tomography case.

Evolution shows that photonic structures are a constituent part of many animals and flora. These elements produce structural color and are useful in predator-prey interactions between animals and in the exploitation of light for photosynthetic organisms. In particular, diatoms have evolved patterned hydrated silica external valves able to confine light with extraordinary efficiency. Their evolution was probably guided by the necessity to survive in harsh conditions of sunlight deprivation. Here, we exploit such diatom valves, in conjunction with structured illumination, to realize a biological super-resolving lens to achieve sub-diffractive focusing in the far field. More precisely, we consider a single diatom valve of Arachnoidiscus genus which shows symmetries and fine features. By characterizing and using the transmission properties of this valve using the optical eigenmode technique, we are able to confine light to a tiny spot with unprecedented precision in terms of resolution limit ratio, corresponding in this case to 0.21λ/NA.

In this paper, an advanced model for predicting behaviour of RC beams, including effects of material nonlinearity and tension stiffening, has been adopted in order to investigate how randomness in mechanical weldable steel properties affects the estimate of the available rotational capacity. The mechanical properties characterising steel behaviour which are assumed to be random are: strain at the peak stress (Agt), yield stress (fsy) and the ratio of the peak stress (fsu) to the yield one (hardening ratio fsu/fsy).

Liposomes are lipid vesicles largely investigated in the past 30 years as pharmaceutical carriers. In the development of new liposome-based formulations, the study of liposome surface properties remains a crucial step. For this purpose, microscopy techniques can provide useful information, although each such technique suffers from some limitations. Here, we have used cold field emission gun-scanning electron microscopy (cFEG-SEM) to acquire detailed images of liposome surface. In particular, we observed PEGylated and non-PEGylated liposomes in different size ranges. In the case of nanosized liposomes (mean diameter about 200 nm), a morphological evaluation of the whole preparation was obtained. On the other hand, in the case of giant liposomes (mean diameter about 2 μm), it was possible to observe the different surface ultrastructures of the two formulations. In particular, a regular and only slightly wrinkled surface was observed in the case of non-PEGylated liposomes, while a very irregular surface ultrastructure was visible in the case of PEGylated liposomes. This study shows, for the first time, the potential of cFEG-SEM as a new and powerful tool to obtain information on liposome morphology and, at least in the case of giant liposomes, on ultrastructure of the liposome surface. © 2008 Elsevier B.V. All rights reserved.

Biosilicified nanostructured microshells from the marine diatom Coscinodiscus wailesii have been properly functionalised to bind a molecular probe which specifically recognises a target analyte. The chemical modification process has been characterised by Fourier transformed infrared spectroscopy. Fluorescence measurements demonstrate that the antibodies we used, even if linked to the amorphous silica surface of C. wailesii microshells, still efficiently recognise their antigens. These low cost and largely available natural materials can be thus used as transducers elements for optical biosensors or as targeting microcapsules for drug delivery

The seismic response of single storey asymmetric structures modelled as two-degree-of-freedom elastic-perfectly plastic oscillators and designed using the design eccentricity formula of the present Uniform Building Code (UBC) torsional provisions, which first appeared in the 1988 edition, is compared with designs based on the earlier UBC 1979. Changes in the total strength requirement and its distribution among the resisting elements are examined, and the effects of these changes on the ductility demand of three-and five-element systems are evaluated. Jt is shown that for two levels of the strength reduction factor R (= 4;1) the ductility demands predicted for systems designed according to the UBC 79 provisions are in most cases similar to those for UBC 88 systems, with the exception of torsionally flexible systems - mainly mass eccentric and, to a much lesser extent, stiffness eccentric systems. In view of the relative complexity of the UBC 88 provisions, a modification of the simpler UBC 79 ones is proposed which results in the UBC 79 torsionally flexible systems behaving in a similar and often better manner than their UBC 88 counterparts.

Near-surface characterization is an important part of seismic data processing, especially for land data. Conventional approaches rely on refracted waves and use of inversion techniques to estimate compression-wave velocity models from the first-break traveltimes. However, in a complex geologic setting in the shallow part of the subsurface, velocity inversions and hidden layers may reduce the reliability of the refraction solution, even with high-quality first breaks. Surface-wave inversion techniques provide shear-wave velocity models that can be integrated in the near-surface characterization workflow. The VP and VS models inferred from first-break traveltimes and Rayleigh waves have several synergies. Their integration can provide an effective solution for challenging geological situations. A robust way of integrating the two methods is simultaneous joint inversion: within this inversion scheme, the two measurements, together with some geological and/or petrophysical relationships linking the subsurface properties, are used in the computation of a unique cost function, which is to be minimized. The solution of the inverse problem results in a multiproperty model fitting data of both measurements and the linking relationship. Different portions of the model are resolved by the interacting contributions of complementary measurements. A field example from Kuwait is discussed to demonstrate the method.

This paper explores the influence of spectrum-matched and amplitude-scaled ground motions on the development of fragility functions for structures. The quantification of the influence of these two types of ensembles on ground motions in predicting demands of structural and nonstructural systems is addressed. Moreover, the paper investigates the sensitivity of number of accelerograms in the ensembles, which produces consistent results in the nonlinear analyses. A multidegree-of-freedom (MDOF) inelastic shear-type building is used in the evaluations. The median and the dispersion of different types of damage measures are evaluated at each story and the effect of different levels of nonlinearity is investigated. Fragility functions are developed for structural and nonstructural components using the maxi- mum likelihood method from the response generated with the selected ground motions. The sufficient number of ground motions necessary in the estimation of the response parameters and on the evaluation of the fragility functions is presented herein. DOI: 10.1061/(ASCE)ST.1943- 541X.0000115. © 2011 American Society of Civil Engineers. CE Database subject headings: Damage; Nonlinear analysis; Simulation; Earthquakes; Inelasticity. Author keywords: Damage; Fragility functions; Intensity measure; Nonlinear analysis; Record selection; Uniform hazard spectrum; Spec- trum matching; Stationary simulation; Synthetic earthquakes; Acceleration scaling; Accelerograms matching; Inelastic demand.

Fin dalle prime descrizioni cliniche risalenti alla fine del XIX secolo, nei pazienti affetti da SM viene segnalata la possibile presenza di sintomi psichiatrici accanto ai deficit motori, sensitivi e sensoriali. Tuttavia, mentre dall’insieme degli studi presenti in letteratura emerge come frequente l’associazione tra i sintomi somatici della SM e i disturbi dell’umore, in particolare la depressione, risultano invece molto meno studiate le alterazioni della percezione, la disorganizzazione del pensiero e i disturbi comportamentali.

The characterization of partially coherent light transmission by micrometer sized valves of marine diatoms is an interesting optical challenge and, from the biological point of view, is of outmost relevance in order to understand evolution mechanisms of such organisms. In the present work, we have studied the transmission of light coming from a monochromator through single valves of Coscinodiscus wailesii diatoms. Incoming light is confined by the regular pore pattern of the diatom surface into a spot of few microns, its dimensions depending on wavelength. The effect is ascribed to the superposition of wavefronts diffracted by the pores' edges. Numerical simulations help to demonstrate how this effect is not present in the ultraviolet region of the light spectrum, showing one of the possible evolutionary advantages represented by the regular pores patterns of the valves. © 2010 Optical Society of America.

Valves of Coscinodiscus wailesii diatoms, monocellular micro-algae characterized by a diameter between 100 and 200 μm, show regular pores patterns which confine light in a spot of few μm2. This effect can be ascribed to the superposition of diffracted wave fronts coming from the pores on the valve surface. We studied the transmission of partially coherent light, at different wavelengths, through single valves of Coscinodiscus wailesii diatoms. The spatial distribution of transmitted light strongly depends on the wavelength of the incident radiation. Numerical simulations help to demonstrate how this effect is not present in the ultraviolet region of the light spectrum, showing one of the possible evolutionary advantages represented by the regular pores patterns of the valves. Valves of Coscinodiscus wailesii diatoms, monocellular micro-algae characterized by a diameter between 100 and 200 mu m, show regular pores patterns which confine light in a spot of few mu m(2). This effect can be ascribed to the superposition of diffracted wave fronts coming from the pores on the valve surface. We studied the transmission of partially coherent light, at different wavelengths, through single valves of Coscinodiscus wailesii diatoms. The spatial distribution of transmitted light strongly depends on the wavelength of the incident radiation. Numerical simulations help to demonstrate how this effect is not present in the ultraviolet region of the light spectrum, showing one of the possible evolutionary advantages represented by the regular pores patterns of the valves.

This paper illustrates an advanced process for integration: 3D simultaneous joint inversion (SJI) of seismic, electromagnetic, and gravity data to better define the base salt in the Green Canyon-Garden Banks-Keathley Canyon-Walker Ridge areas. SJI enhances the ambition of improving the existing velocity models for prestack depth migrations and the consistency of seismic and non-seismic representations of the subsurface in complex salt geometries. We produced a new structural framework with renewed interpretations of the allochthonous and autochthonous salt, providing new tools for interpretation of the complex salt, reducing inversion uncertainties, and most importantly, defining a new strategy for subsalt interpretation, thereby enhancing the role of non-seismic methods as supporting complex seismic depth imaging.

Amoebic liver abscess (ALA) is the most common extraintestinal complication of colonic amebiasis. In recent decades its incidence in developed European countries has significantly increased because of travel and immigration of individuals from highly endemic areas. We report our 29-year experience in echo-guided percutaneous needle/catheter drainage (EPND/EPCD) of ALA.From May 1979 to November 2007, 68 ALA corresponding to 56 patients were diagnosed at our Department. All patients were treated with a metronidazole plus EPND/EPCD approach.The majority of the cases did not need more than two echo-guided punctures. Two patients, both male immigrants (HIV-negative), had unmodified lesions after two EPNDs: catheter drainage was performed. A quick worsening of their clinical conditions and onset of neurological symptoms occurred; in both patients, computed tomography (CT) revealed a brain abscess. Intravenous medical therapy was started, but both died 4 and 3 days, respectively, after the onset of neurological symptoms (overall mortality rate: 3.57%).The unfavorable outcome of two cases is a rare example of failure of percutaneous therapy of ALA. Mortality is a possible event even in a non-endemic area such as Italy. More observational data are needed to confirm the possibility of a new epidemiological trend.

O Estado de São Paulo é o principal produtor de uvas de mesa do país, sendo a Niágara Rosada (Vitis Labrusca) a cultivar predominante. Para se oferecer produtos de qualidade ao mercado, os produtores necessitam determinar, periodicamente, o estado de maturação das uvas, sendo o teor de sólidos solúveis (tss), a principal variável avaliada. Para essa determinação, utiliza-se a amostragem dos frutos na área cultivada. O presente trabalho discute, assim, os métodos de amostragem estratificado e aleatório simples, e o tamanho adequado da amostra de baga individual, para avaliar o estado de maturação da uva Niágara Rosada, com base no teor de sólidos solúveis. O tamanh o adequado da amostra de b ag a individual foi encontrado para os dois métodos de amostrag em, separadamente, utilizando-se os métodos da Máxima Curvatura Modificado e Curva da Variância. Os métodos de amostrag em foram comparados utilizando-se uma análise univariada para dados com medidas repetidas, através dos procedimentos GLM e MIX ED do SAS. F oram utilizados dois procedimentos, para q ue se produz isse resultados confiáveis. Os tamanhos mínimos de amostras de baga individual req ueridos, para os métodos estratificado e aleatório simples foram aproximadamente 3 0 e 2 7 bagas por área, respectivamente. Os métodos de amostrag em estudados apresentaram diferença signicativa, e o método aleatório simples apresentou grande variação máxima e mínima por planta, devendo assim, ser evitado para esse tipo de estudo. Made available in DSpace on 2019-11-02T00:36:28Z (GMT). No. of bitstreams: 1 119052009p.501518.pdf: 7197993 bytes, checksum: 9677f3ec8090bb1b0f8b9c686dc4493f (MD5) Previous issue date: 2009

In 11 children (mean age 44.2 months) with symptoms suggesting upper intestinal dysfunction (nonulcer dyspepsia), in nine children (mean age 27.3 months) with gastroesophageal reflux (GER) disease, and in seven controls (mean age 20.4 months) we investigated fasting [for 3 hr or until two migrating motor complexes (MMC) were observed] and fed (90 min) antroduodenal motility by means of perfused catheter system; furthermore, we measured both gastric emptying of a radiolabeled milk formula and fasting duodenogastric reflux during manometry by assessing bile salt concentration in gastric aspirates. No structural abnormalities of gastrointestinal tract and organic disorders were detected in the patients. In a high proportion of both groups of patients we found manometric abnormalities of interdigestive and fed motor patterns that were not seen in the controls: absence of antral phase III of MMC; significant decrease of antral and/or duodenal motor activity during fasting and/or fed periods; abnormal propagation or configuration of MMC phase III that was significantly shorter than in controls; bursts of sustained fasting and/or fed phasic duodenal activity, frequently uncoordinated with adjacent gut segments. When compared to controls, the mean intragastric concentration of bile salts during all MMC phases and the mean 1-hr percent gastric activity of the radiolabeled milk were significantly higher in the two groups of patients. We conclude that in a high proportion of children with nonulcer dyspepsia and of children with GER disease, gastrointestinal manometry may reveal significant irregularities of antral and duodenal motility, which are associated with increased duodenogastric reflux and delayed gastric emptying.

In recent years, the moment-rotation response of double angle shear connections has been examined in depth. However, the response of these connections to applied axial force has not been studied so extensively. This paper presents two models of the behavior of double angle shear connections subjected to axial load, which are based on the physical behavior of test specimens that were subjected to axial force until failure. The proposed models, which map design characteristics of double angle connections into actual behavior, yielded good correlation with the experimental results.

Diatoms are monocellular micro-algae provided with external valves, the frustules, made of amorphous hydrated silica. Frustules present patterns of regular arrays of holes, the areolae, characterized by sub-micrometric dimensions. In particular, frustules from centric diatoms are characterized by a radial disposition of areolae and exhibit several optical properties, such as photoluminescence variations in presence of organic vapors and photonic-crystal-like behaviour as long as propagation of electromagnetic field is concerned. We have studied the transmission of coherent light, at different wavelengths, through single frustules of Coscinodiscus Walesii diatoms, a centric species characterized by a diameter of about 150 μm. The frustules showed the ability to focalize the light in a spot of a few μm2, the focal length depending on the wavelength of the incident radiation. This focusing effect takes place at the centre of the frustule, where no areolae are present and, as it is confirmed by numerical simulations, it is probably due to coherent superposition of unfocused wave fronts coming from the surrounding areolae. Diatoms-based micro-lenses could be used in the production of lensed optical fibers without modifying the glass core and, in general, they could be exploited with success in most of the optical micro-arrays. Diatoms are monocellular micro-algae provided with external valves, the frustules, made of amorphous hydrated silica. Frustules present patterns of regular arrays of holes, the areolae, characterized by sub-micrometric dimensions. In particular, frustules from centric diatoms are characterized by a radial disposition of areolae and exhibit several optical properties, such as photoluminescence variations in presence of organic vapors and photonic-crystal-like behaviour as long as propagation of electromagnetic field is concerned. We have studied the transmission of coherent light, at different wavelengths, through single frustules of Coscinodiscus Walesii diatoms, a centric species characterized by a diameter of about 150 urn. The frustules showed the ability to focalize the light in a spot of a few μm2, the focal length depending on the wavelength of the incident radiation. This focusing effect takes place at the centre of the frustule, where no areolae are present and, as it is confirmed by numerical simulations, it is probably due to coherent superposition of unfocused wave fronts coming from the surrounding areolae. Diatoms-based micro-lenses could be used in the production of lensed optical fibers without modifying the glass core and, in general, they could be exploited with success in most of the optical micro-arrays.

The Authors present a rare case of voluminous retroperitoneal tumor in a 41 years old woman. CT scan showed a solid abdominal expansive mass, with compression and displacement of the left lobe of the liver, spleen, stomach, pancreas, and left kidney. The patient underwent surgery for excision of a giant retroperitoneal mass. Surgery was uneventful. The patients recovered well. Histology showed a mixed liposarcoma and angiosarcoma with high grade of malignancy and positivity for vimentin, factor VIII, CD34, CD31 and negativity for S-100, CD68, AMS, AML. The prognosis of these tumours is closely related to local recurrence, histological type, size and radical surgery. A low-grade malignancy tumor, small sized and completely resected leads to a good prognosis. Radiation therapy and chemotherapy do not seem to have a strong influence on the prognosis. An aggressive surgical approach is the first choice for the treatment of such tumors. The resection of adjacent organs may be required for radical surgery.

Marine diatoms are microscopic algae living in aquatic environment; their skeleton, made of amorphous silica, possesses a complex geometrical structure that presents holes on different length scales in a fractal-like fashion, achieving a high surface-to-volume ratio and making them good candidates for gas detecting purposes. Indeed, different gas species can influence diatoms' photoluminescence emission according to their different polarizing abilities. In particular, to exploit marine diatoms as optical nitrogen dioxide sensors and in order to get a better insight on the nature of the photoluminescence quenching process induced by the gas molecules, continuous-wave and time-resolved photoluminescence studies have been carried out, showing that nitrogen dioxide affects only the photoluminescence yield without altering the dynamics of the recombination process. (C) 2007 Elsevier B.V. All rights reserved.

Biosilicified nanostructured microshells from the marine diatom Coscinodiscus wailesii have been properly functionalised to bind a molecular probe which specifically recognises a target analyte. The chemical modification process has been characterised by Fourier transformed infrared spectroscopy. Fluorescence measurements demonstrate that the antibodies we used, even if linked to the amorphous silica surface of C. wailesii microshells, still efficiently recognise their antigens. These low cost and largely available natural materials can be thus used as transducers elements for optical biosensors or as targeting microcapsules for drug delivery. © 2007 Acta Materialia Inc.

C004 Pre-Stack Depth Imaging Via Simultaneous Joint Inversion of Seismic Gravity and Magnetotelluric Data M. De Stefano (Geosystem SRL) & D. Colombo* (Geosystem SRL) SUMMARY The problem of velocity model building for depth-imaging applications (i.e. Pre-Stack Depth Migration) is approached from the point of view of simultaneous Joint Inversion of multiple geophysical domains. For this purpose a general formulation of the joint inversion problem is provided which integrates geological constraints within a data-driven procedure. The method is then applied to synthetic (long offset) seismic data where seismic travel-time residuals (first-break and post-migration Common Image Gather residuals) are jointly inverted with

Rapporto campagna oceanografica a bordo M/N ITALICA

It is well known by far that biological organisms could exhibit sophisticated optical system, which compete or overcame the top technology products available. The diatoms are microscopic algae enclosed in intricate amorphous silica cells, called frustules. In this work the optical reflectivity data, infrared spectroscopy, scanning electron microscopy and photoluminescence (PL) characterizations are presented for silica shells of Coscinodiscus wailesii, which is a centric diatom characterized from a diameter that varies in the range between 100 and 500 μm. Preliminary results suggest that the Coscinodiscus wailesii can be used as photonic material and sensor transducer. It is well known by far that biological organisms could exhibit sophisticated optical system, which compete or overcame the top technology products available. The diatoms are microscopic algae enclosed in intricate amorphous silica cells, called frustules. In this work the optical reflectivity data, infrared spectroscopy, scanning electron microscopy and photoluminescence (PL) characterizations are presented for silica shells of Coscinodiscus wailesii, which is a centric diatom characterized from a diameter that varies in the range between 100 and 500 μm. Preliminary results suggest that the Coscinodiscus wailesii can be used as photonic material and sensor transducer.

We consider Pisciarelli (Campi Flegrei, Italy) as a model site for investigating the factors which influence the distribution of microalgae in hydrothermal environments. This hydrothermal system is liquid-dominant with very low pH values both in water and in the soil; spring water has a temperature of up to 92°C. At Pisciarelli, chemico-physical conditions are extremely variable in different sites, seasons and years. Five ecological stations were identified on the basis of temperature, pH and fluid vents conditions. Different algal communities have been observed according to their adaptability to these controlling factors. Cyanidiales were found to be largely diffused in the entire area, proving very successful at adapting to environmental changes. Chlamydomonas sp. and Pinnularia sp. were scattered in at least three of the five ecological stations. Some green acid-tolerant algae, such as Pseudococcomyxa simplex and Chlorella protothecoldes var. acidicola, were strongly influenced by temperature and pH fluctuations and mainly limited to one station. Dunaliella acidophila is confined to a narrow area, being able to live exclusively in restricted pH and temperature ranges. In some sampling sites the peculiar chemico-physical conditions together with silica oversaturation cause the formation of a thick silica crust around cell walls. Generally, algae could act as a nucleation site for neoforming minerals, offering in some cases an ideal substrate for the formation of a thick silica crust on their surface We consider Pisciarelli (Campi Flegrei, Italy) as a model site for investigating the factors which influence the distribution of microalgae in hydrothermal environments. This hydrothermal system is liquid-dominant with very low pH values both in water and in the soil; spring water has a temperature of up to 92°C. At Pisciarelli, chemico-physical conditions are extremely variable in different sites, seasons and years. Five ecological stations were identified on the basis of temperature, pH and fluid vents conditions. Different algal communities have been observed according to their adaptability to these controlling factors. Cyanidiales were found to be largely diffused in the entire area, proving very successful at adapting to environmental changes. Chlamydomonas sp. and Pinnularia sp. were scattered in at least three of the five ecological stations. Some green acid-tolerant algae, such as Pseudococcomyxa simplex and Chlorella protothecoldes var. acidicola, were strongly influenced by temperature and pH fluctuations and mainly limited to one station. Dunaliella acidophila is confined to a narrow area, being able to live exclusively in restricted pH and temperature ranges. In some sampling sites the peculiar chemico-physical conditions together with silica oversaturation cause the formation of a thick silica crust around cell walls. Generally, algae could act as a nucleation site for neoforming minerals, offering in some cases an ideal substrate for the formation of a thick silica crust on their surface.