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1.
Opt Express ; 27(11): 15956-15967, 2019 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-31163784

RESUMO

We introduce a high-performance hyperspectral camera based on the Fourier-transform approach, where the two delayed images are generated by the Translating-Wedge-Based Identical Pulses eNcoding System (TWINS) [Opt. Lett. 37, 3027 (2012)], a common-path birefringent interferometer that combines compactness, intrinsic interferometric delay precision, long-term stability and insensitivity to vibrations. In our imaging system, TWINS is employed as a time-scanning interferometer and generates high-contrast interferograms at the single-pixel level. The camera exhibits high throughput and provides hyperspectral images with spectral background level of -30dB and resolution of 3 THz in the visible spectral range. We show high-quality spectral measurements of absolute reflectance, fluorescence and transmission of artistic objects with various lateral sizes.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 219: 504-508, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31078817

RESUMO

We present a multi-analytical in situ non-invasive study of a series of emblematic paintings by Alessandro Milesi (1856-1945) from the collection of the International Gallery of Modern Art Ca' Pesaro in Venice. Eight paintings dated from 1897 to 1910 were studied with imaging and spectroscopic techniques. White pigments were characterized by a combination of X-ray fluorescence spectroscopy which traced the presence of zinc-based pigments in Milesi's paintings, Raman Spectroscopy, Laser Induced Fluorescence (LIF) Spectroscopy and Time-resolved Luminescence Imaging. Time-resolved analysis of luminescence emissions revealed the nanosecond emission from organic compounds and the slower emission from the luminescent inorganic pigment Zinc Oxide that varied between 1.1 and 1.6 microseconds. In this work, data regarding the distribution of luminescent pigments was acquired with a time-gated imaging detector. Furthermore, differences in emission decay kinetics recorded from different paintings can be ascribed to different paint formulations or origins of the Zinc white in paint.

3.
Spectrochim Acta A Mol Biomol Spectrosc ; 219: 530-538, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31078820

RESUMO

A complementary multi-analytical in-situ approach has been adopted for the investigation of a corpus of ten paintings dating from 1889 and 1940 by the Venetian painter Alessandro Milesi (1856-1945), from the collection of the International Gallery of Modern Art Ca' Pesaro in Venice. Analyses were performed in situ with digital imaging, elemental and spectroscopic analysis. The analysis of pigments and binding media and their possible deterioration patterns were studied with a combination of X-Ray Fluorescence (XRF) Spectroscopy, External Reflection- Fourier Transform Infrared Spectroscopy (ER-FTIR) and Raman Spectroscopy. These analytical methods provide information regarding the evolution of the artist's palette and the painting techniques adopted in painting. Data suggest the widespread detection of zinc carboxylates, with implications for conservation and display.

4.
J Epidemiol Glob Health ; 2(1): 31-8, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23856396

RESUMO

BACKGROUND: A marked geographic variability has been reported in stone disease, partially attributed to the Mean Annual Temperature (MAT), as well as to the seasonal fluctuations of climatic conditions. Accordingly, peaks in Emergency Department (ED) visits for renal colic are commonplace during the summer. MATERIALS AND METHODS: The aim of this study was to assess the influence of day-by-day climate changes on the number of visits as a result of renal colic in the ED (City of Parma, northern Italy, temperate continental climate). A total of 10,802 colic episodes were retrieved from the database during a period of 3286days (January 2002 to December 2010). RESULTS: The analysis of the data confirms a peak of renal colic cases during the summer, especially in July (maximum number of 4.1 cases of renal colic per day), and a winter nadir (minimum number of 2.7 cases of renal colic per day, in February). The linear regression analysis shows a high and significant correlation between the mean number of cases of renal colic per day and both the mean daily temperature (positive association, R=0.93; p<0.0001) and the mean daily humidity (negative association, R=-0.82; p<0.0001). The influence of temperature and humidity on the incidence of renal colic cases varied widely among age groups, the highest incidence seen in patients aged between 30 and 40years, and the lowest seen for those aged <20 and >70years of age. CONCLUSION: The combined data suggest that the hot and dry climate would favor an acceleration of the process of stone formation, which seems more pronounced in the older population.


Assuntos
Clima , Serviço Hospitalar de Emergência/estatística & dados numéricos , Umidade , Cólica Renal/epidemiologia , Cólica Renal/terapia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Estudos de Coortes , Bases de Dados Factuais , Feminino , Hospitais Urbanos , Humanos , Incidência , Itália/epidemiologia , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Cólica Renal/diagnóstico , Estudos Retrospectivos , Medição de Risco , Estações do Ano , Índice de Gravidade de Doença , Adulto Jovem
5.
Appl Spectrosc ; 63(1): 48-56, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19146718

RESUMO

This paper discusses the spectral distortions occurring when time-resolved spectroscopy of diffusive media is performed illuminating with a wide bandpass. It is shown that the spectral region within the bandpass that exhibits the lowest absorption will dominate the resulting time-resolved curve, leading to significant underestimations of absorption as well as distortions in the spectral shape (including shifts in peak positions). Due to the nonlinear behavior of absorption, this effect becomes even more pronounced when including longer and longer photon path lengths. First, a theoretical treatment of the problem is given, and then the distortion is described by time-resolved reflectance simulations and experimental measurements of lipid and water samples. A spectrally constrained data analysis is proposed that takes into account the spectrum of the light injected into the sample, used to overcome the distortion and improve the accuracy of the estimation of chromophore concentrations from absorption spectra. Measurements on a lipid sample show a reduction of the error from 30% to 6%.

6.
Appl Spectrosc ; 62(5): 569-74, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18498699

RESUMO

We have proposed and experimentally demonstrated that picosecond time-resolved optical spectroscopy in the visible/near-infrared (NIR) region (700-1040 nm) is a useful technique for noninvasive characterization of wood. This technique has been demonstrated on both softwood and hardwood samples treated in different ways simulating the aging process suffered by waterlogged woods. In all the cases, alterations of absorption and scattering spectra were observed, revealing changes of chemical and structural composition.


Assuntos
Madeira/química , Vidro , Plásticos , Espectrofotometria Infravermelho/métodos , Análise Espectral/métodos , Fatores de Tempo , Madeira/análise
7.
Phys Rev Lett ; 99(13): 131101, 2007 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-17930572

RESUMO

Theories with an extra spin-two field coupled to gravity admit a massive phase with broken Lorentz symmetry. While the equivalence principle is respected, the Newtonian potentials are in general modified, but they may be protected by a scale symmetry of the coupling term. The gravitational waves phenomenology is quite rich: two gravitons, one massive and one massless, oscillate and propagate with distinct velocities, different from the speed of light. A time of flight difference between gravitons and photons from a common source would provide a clear signal of this theory.

8.
AIDS Patient Care STDS ; 21(11): 833-42, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18240893

RESUMO

The aim of this observational, prospective, nonrandomized study was to assess long-term psychometric outcomes of surgical treatment of HIV-related facial lipoatrophy. Two hundred ninety-nine participants (70.8% male) consecutively attending the Metabolic Clinic of Modena and Reggio Emilia University from November 2005 to July 2006, undergoing surgical interventions for HIV-related facial lipoatrophy were enrolled. Fifty-four (18.1%) underwent facial lipofilling, which consists of the harvesting of a small, intact parcel of fatty tissue with processing that removes the nonviable components and of the transport of fatty parcels through a small cannula to implant the graft in a manner that provides nutrition and anchors the fat to the host tissue. After an initial lipofilling, 24 (8%) needed polylactic acid injections to correct cheek asymmetry, 91 (30.4%) received only polylactic acid infiltrations, and 130 (43.5%) polyacrylamide infiltrations only. Subjective outcome measures were face aesthetic satisfaction, body image perception, depression evaluated by a visual analogue scale (VAS), the Assessment of Body Change and Distress questionnaire (ABCD), and by the Beck Depression Inventory questionnaire, respectively. Objective measure was cheek thickness evaluated by a 7.5-MHz frequency ultrasound probe perpendicular to the skin surface at the nasolabial fold, the corner of the mouth, the zygomatic arch, and centrally between these points in the buccal fat pad area. Both subjective and objective variables were evaluated at baseline and 48 weeks after end of surgical treatment. All 299 participants had significant improvement of the aesthetic satisfaction for the face (VAS from 2.9 +/- 2.1 to 6.2 +/- 2.1, p < 0.0001), of body image satisfaction (ABCD question 7 from 3.8 +/- 1 to 3.1 +/- 1 p < 0.0001 and ABCD question 8 from 70.7 +/- 16.7 to 77.2 +/- 17.2 p < 0.0001), of depression score (Beck score from 11.4 +/- 8.3 to 9.4 +/- 7.8 p = 0.001). Participants experienced a significant augmentation of both cheeks' thickness (right cheek from 4.3 +/- 1.9 mm to 9.5 +/- 3 mm p < 0.0001, left cheek from 4.4 +/- 2 mm to 9.6 +/- 3.1 mm, p < 0.0001). Our data suggest that facial surgery is an important option in the treatment of HIV-related lipoatrophy as an integral part of the management of HIV infection, because of the important and lasting psychological benefits.


Assuntos
Adaptação Psicológica , Tecido Adiposo/transplante , Dermatoses Faciais/cirurgia , Síndrome de Lipodistrofia Associada ao HIV/cirurgia , Satisfação do Paciente , Imagem Corporal , Depressão , Estética , Dermatoses Faciais/diagnóstico por imagem , Dermatoses Faciais/psicologia , Feminino , Síndrome de Lipodistrofia Associada ao HIV/diagnóstico por imagem , Síndrome de Lipodistrofia Associada ao HIV/psicologia , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Observação , Fotografação , Psicometria , Resultado do Tratamento , Ultrassonografia
9.
G Ital Med Lav Ergon ; 28(1 Suppl 1): 22-8, 2006.
Artigo em Italiano | MEDLINE | ID: mdl-19024892

RESUMO

This study sought to investigate some psychological issues related to multiple sclerosis (MS), in particular, the relations existing between illness representations, personality factors and coping strategies and, consequently, the specific coping strategies employed in adjusting emotionally to MS. Sixty-nine MS patients attending the University Polyclinic of Modena were administered the following battery: a questionnaire regarding demographic and illness features, the Illness Perception Questionnaire-Revised (IPQ-R), the Coping Orientations to Problems Experienced Questionnaire (COPE) and Cognitive Behavioural Assessment Hospital Form (CBA-H). Patients' physical disability level was also evaluated using the Expanded Disability Status Scale (EDSS). Results suggest that personality factors and patients' perception of their illness play an important role in activating one or other type of coping strategy. Regarding problem-focused coping strategies, the most significant predictors that emerged from stepwise linear multiple regression analysis were perception of the disease as cyclical (timeline cyclical dimension) and a low score in neuroticism, indicating good emotional stability of the subject. For emotion-centered coping strategies, the regression model identified as best predictors: the belief that chance or bad luck are the most important causes of the illness, perception of the disease as cyclical, extroversion and a cooperative mode of interacting with others, and the presence of interpersonal difficulties. Finally, with regard to disadaptive coping strategies, the best predictors resulting from the analysis were, once again, perception of the disease as cyclical, and interpersonal difficulties.


Assuntos
Esclerose Múltipla/psicologia , Adaptação Psicológica , Adulto , Feminino , Humanos , Masculino , Inquéritos e Questionários
10.
Opt Express ; 13(25): 10075-84, 2005 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-19503220

RESUMO

A system based on a picosecond time-gated image intensifier is proposed for non-contact testing of CMOS circuits. The apparatus allows one to record the temporal evolution of the luminescence emitted during transistor switching as a function of the position inside the chip. The system is characterized by an intrinsic parallelism in the spatial dimensions. This feature is noticeable for studying wide sections of complex circuits, like microprocessors and random access memories, where multiple electrical events occur simultaneously. Experiments on a CMOS inverter chain and on a static memory have been carried out, in order to demonstrate the applicability of a picosecond time-gated imager to circuit analysis.

11.
Phys Rev Lett ; 87(21): 211802, 2001 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-11736331

RESUMO

We point out that, in a spontaneously broken U(1) gauge theory, inclusive processes, whose primary particles are mass eigenstates that do not coincide with the gauge eigenstates, are not free of infrared logarithms. The charge mixing allowed by symmetry breaking and the ensuing Bloch-Nordsieck violation are here analyzed in a few relevant cases and in particular for processes initiated by longitudinal gauge bosons. Of particular interest is the example of weak hypercharge in the standard model where, in addition, left-right mixing effects arise in transversely polarized fermion beams.

12.
Photochem Photobiol ; 72(5): 690-5, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11107856

RESUMO

A fluorescence imaging system was used to monitor the emission of disulfonated aluminum phthalocyanine (AlS2Pc) during the photodynamic therapy (PDT) of murine tumors. Cells of the MS-2 fibrosarcoma were injected in mice in two compartments in order to cause the development of tumors in different host tissues. Two drug doses and two uptake times were considered. Moreover, the fluorescence of the AlS2Pc was excited using two wavelengths on the opposite sides of the absorption peak to detect a possible change in the absorption spectrum of the sensitizer induced by the PDT. In the tumors, the treatment induces a variation of the fluorescence intensity: in some mice a mild photobleaching takes place, in others a fluorescence enhancement occurs. Which effect predominates depends on the experimental conditions, even though a large spread of data was found amongst mice of the same group. In all mice, independently of the drug dose, uptake time or tumor compartment, a marked increase in the fluorescence signal takes place at the borders of the irradiated area. To quantify this effect we evaluated the ratio between the fluorescence intensities in the peritumoral area and in the tumor itself. This ratio increases monotonically during the PDT, showing a different behavior with the two excitation wavelengths. This indicates that the AlS2Pc absorption spectrum shifts toward shorter wavelengths as a result of the irradiation.


Assuntos
Fotoquimioterapia , Sarcoma Experimental/tratamento farmacológico , Animais , Fluorescência , Indóis/uso terapêutico , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos DBA , Compostos Organometálicos/uso terapêutico , Fármacos Fotossensibilizantes/uso terapêutico
13.
Phys Rev Lett ; 84(21): 4810-3, 2000 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-10990804

RESUMO

We point out that, since the colliders' initial states ( e(+)e(-),pp, p&pmacr;,ellipsis) carry a definite non-Abelian flavor, electroweak radiative corrections to inclusive hard cross sections at the TeV scale are affected by peculiar Bloch-Nordsieck violating double logs. We recall the setup of soft cancellation theorems, and we analyze the magnitude of the noncanceling terms in the example of electron-positron annihilation into hadrons.

14.
Opt Lett ; 25(22): 1648-50, 2000 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-18066303

RESUMO

We describe a novel technique for DNA-microarray reading based on time-resolved fluorescence measurements. We used an intensified CCD camera with picosecond resolution to acquire a set of time-delayed fluorescence images from a mutation DNA microarray marked with cyanine 3. We measured the fluorescence lifetimes of the marker and the background separately, and we used this information to calculate the amplitude map of the marker, starting from the time-delayed images. This procedure allowed us to identify hybridized spots that are not visible in fluorescence images acquired with continuous-wave detection.

15.
Phys Rev D Part Fields ; 54(1): 1176-1181, 1996 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-10020584
16.
Phys Rev D Part Fields ; 53(9): 5222-5232, 1996 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-10020518
19.
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