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1.
Analyst ; 149(8): 2317-2327, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38466379

RESUMO

We investigate the subsurface composition of turbid materials at the micro scale by means of a portable non-invasive technique, micro-spatially offset Raman spectroscopy (micro-SORS), combined with shifted excitation Raman difference spectroscopy (SERDS). This combination enables the microscale layer analysis and allows to deal effectively with highly fluorescing samples as well as ambient light, all in a form of an in-house portable prototype device optimised for applications in heritage science. The instrument comprises ability to simultaneously collect multiple spectra by means of an optical fibre bundle, thus reducing the dead time and simplifying the ease of deployment of the technique. The performance of the synergy between micro-SORS and 785 nm SERDS dual-wavelength diode laser is demonstrated on a stratified mock-up painting samples including highly fluorescing painted layers. This instrumental approach could be ground-breaking in heritage science, due to the largely unmet need of analysing the molecular composition of subsurface of artworks non-invasively and in situ, and in the presence of fluorescent background and ambient light. Moreover, many other fields are expected to benefit from this technological advancement such as solar energy, forensic and food analytical areas.

2.
Neurol Sci ; 44(12): 4233-4245, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37542547

RESUMO

OBJECTIVE: The scope of this paper is to review the subtypes of transient ischemic attack (TIA) and minor stroke (mS) in which a surgical treatment is needed, discussing the importance and the timing of a multidisciplinary approach, in order to achieve an optimized management and prevent major strokes or other critical complications. MATERIALS AND METHODS: The keywords "transient ischemic attack," "minor stroke," "surgical treatment," "vascular surgery," "heart surgery," "neurosurgery," and "multidisciplinary" were searched using MEDLINE, EMBASE, and Scopus. Relevant search results were discussed by the authors for references inclusion. RESULTS: Notwithstanding that best medical therapy is usually the first choice for the most part of cases, there are specific but recurrent etiologies that must be properly recognized because of a potential surgical approach, even in urgency. In fact, symptomatic carotid stenosis, or particular cases of hemodynamic cerebrovascular events, should be promptly referred to vascular surgeon, since increasing evidences highlighted a benefit from an early artery revascularization. In addition, beyond arrhythmic causes, cardioembolic events due to bacterial endocarditis and atrial myxoma should be quickly diagnosed, possibly in emergency department, because they are a presumptive urgency for heart surgery. In addition to the above-mentioned conditions, in patients suffering from vertebrobasilar TIA or mS, clinicians should keep in mind the Bow Hunter disease, because surgical artery decompression can represent the only suitable treatment in selected cases. CONCLUSIONS: TIA and mS require a multidisciplinary in order to discuss therapeutic options, comparing risks and benefits and determining the best timing for an optimized management.


Assuntos
Estenose das Carótidas , Ataque Isquêmico Transitório , Acidente Vascular Cerebral , Cirurgiões , Humanos , Ataque Isquêmico Transitório/complicações , Ataque Isquêmico Transitório/terapia , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/terapia , Acidente Vascular Cerebral/diagnóstico , Estenose das Carótidas/complicações , Prevenção Secundária , Fatores de Risco
3.
Opt Lett ; 44(19): 4841-4844, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31568456

RESUMO

Light propagating through random media produces characteristic speckle patterns, directly related to the large multitude of scattering events. These complex dynamics remarkably display robustness to perturbation of the incoming light parameters, maintaining correlation in the scattered wavefront. This behavior is known as the optical memory effect. Here we unveil the properties of the nonlinear optical memory effect, which occurs when an optothermal nonlinearity perturbs the random material. The effect is characterized through a series of pump and probe experiments in silica aerogel, in the visible range. This additional degree of freedom further generalizes the memory effect, opening the road to applications based on the nonlinear response of random media.

4.
Phys Rev Lett ; 122(21): 213902, 2019 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-31283311

RESUMO

Quantum and classical physics can be used for mathematical computations that are hard to tackle by conventional electronics. Very recently, optical Ising machines have been demonstrated for computing the minima of spin Hamiltonians, paving the way to new ultrafast hardware for machine learning. However, the proposed systems are either tricky to scale or involve a limited number of spins. We design and experimentally demonstrate a large-scale optical Ising machine based on a simple setup with a spatial light modulator. By encoding the spin variables in a binary phase modulation of the field, we show that light propagation can be tailored to minimize an Ising Hamiltonian with spin couplings set by input amplitude modulation and a feedback scheme. We realize configurations with thousands of spins that settle in the ground state in a low-temperature ferromagneticlike phase with all-to-all and tunable pairwise interactions. Our results open the route to classical and quantum photonic Ising machines that exploit light spatial degrees of freedom for parallel processing of a vast number of spins with programmable couplings.

5.
Br J Dermatol ; 181(3): 512-522, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30693469

RESUMO

BACKGROUND: Recessive dystrophic epidermolysis bullosa (RDEB), Kindler syndrome (KS) and xeroderma pigmentosum complementation group C (XPC) are three cancer-prone genodermatoses whose causal genetic mutations cannot fully explain, on their own, the array of associated phenotypic manifestations. Recent evidence highlights the role of the stromal microenvironment in the pathology of these disorders. OBJECTIVES: To investigate, by means of comparative gene expression analysis, the role played by dermal fibroblasts in the pathogenesis of RDEB, KS and XPC. METHODS: We conducted RNA-Seq analysis, which included a thorough examination of the differentially expressed genes, a functional enrichment analysis and a description of affected signalling circuits. Transcriptomic data were validated at the protein level in cell cultures, serum samples and skin biopsies. RESULTS: Interdisease comparisons against control fibroblasts revealed a unifying signature of 186 differentially expressed genes and four signalling pathways in the three genodermatoses. Remarkably, some of the uncovered expression changes suggest a synthetic fibroblast phenotype characterized by the aberrant expression of extracellular matrix (ECM) proteins. Western blot and immunofluorescence in situ analyses validated the RNA-Seq data. In addition, enzyme-linked immunosorbent assay revealed increased circulating levels of periostin in patients with RDEB. CONCLUSIONS: Our results suggest that the different causal genetic defects converge into common changes in gene expression, possibly due to injury-sensitive events. These, in turn, trigger a cascade of reactions involving abnormal ECM deposition and underexpression of antioxidant enzymes. The elucidated expression signature provides new potential biomarkers and common therapeutic targets in RDEB, XPC and KS. What's already known about this topic? Recessive dystrophic epidermolysis bullosa (RDEB), Kindler syndrome (KS) and xeroderma pigmentosum complementation group C (XPC) are three genodermatoses with high predisposition to cancer development. Although their causal genetic mutations mainly affect epithelia, the dermal microenvironment likely contributes to the physiopathology of these disorders. What does this study add? We disclose a large overlapping transcription profile between XPC, KS and RDEB fibroblasts that points towards an activated phenotype with high matrix-synthetic capacity. This common signature seems to be independent of the primary causal deficiency, but reflects an underlying derangement of the extracellular matrix via transforming growth factor-ß signalling activation and oxidative state imbalance. What is the translational message? This study broadens the current knowledge about the pathology of these diseases and highlights new targets and biomarkers for effective therapeutic intervention. It is suggested that high levels of circulating periostin could represent a potential biomarker in RDEB.


Assuntos
Vesícula/patologia , Epidermólise Bolhosa Distrófica/patologia , Epidermólise Bolhosa/patologia , Matriz Extracelular/patologia , Fibroblastos/patologia , Doenças Periodontais/patologia , Transtornos de Fotossensibilidade/patologia , Pele/patologia , Xeroderma Pigmentoso/patologia , Adolescente , Adulto , Biópsia , Vesícula/genética , Estudos de Casos e Controles , Células Cultivadas , Criança , Pré-Escolar , Epidermólise Bolhosa/genética , Epidermólise Bolhosa Distrófica/genética , Proteínas da Matriz Extracelular/metabolismo , Feminino , Fibrose , Regulação da Expressão Gênica , Voluntários Saudáveis , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Mutação , Doenças Periodontais/genética , Transtornos de Fotossensibilidade/genética , Cultura Primária de Células , RNA-Seq , Pele/citologia , Xeroderma Pigmentoso/genética , Adulto Jovem
6.
Eur J Contracept Reprod Health Care ; 24(3): 227-232, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30958043

RESUMO

Purpose: The aim of this study is to evaluate the health of oocyte donors and explain how they regard their experience in the long-term. Materials and methods: This is a cross-sectional study in a single fertility centre that consists of a telephone interview guided by a semi-structured questionnaire covering several aspects of reproductive health and personal experience. Results: At the time of interview, 84 out of 121 women (69%) had children while 64 (53%) were already mothers at the time of their donation. Of the 38 women achieving a pregnancy after donation, five reported six pregnancy complications. Two out of 121 (2%) women reported being in menopause (aged 41 and 45). Twenty-three women (19%) reported gynaecological issues and eight (7%) reported fertility problems, although only four consulted a specialist. Most of women highlighted positive feelings about their donation (113, 93%) and 155 (97%) would recommend donating. Less than half (53, 44%) mentioned some negative aspects, mainly related to physical discomfort: injections (20,17%), pain (17, 14%), and side effects of ovarian stimulation (10, 8%). Conclusion: The impact of donation on women's life was mostly favourable, with the majority of participants reporting positive aspects and recommending donation, although some negative feelings as physical discomfort also arose. Therefore, more comfortable stimulation protocols could be developed.


Assuntos
Nível de Saúde , Doação de Oócitos/estatística & dados numéricos , Satisfação do Paciente , Adulto , Estudos Transversais , Feminino , Doenças Urogenitais Femininas/epidemiologia , Seguimentos , Humanos , Infertilidade Feminina/epidemiologia , Injeções/efeitos adversos , Pessoa de Meia-Idade , Doação de Oócitos/efeitos adversos , Doação de Oócitos/psicologia , Indução da Ovulação/efeitos adversos , Dor/etiologia , Paridade , Gravidez , Complicações na Gravidez/epidemiologia , Taxa de Gravidez , Espanha/epidemiologia , Inquéritos e Questionários , Fatores de Tempo
7.
J Biol Regul Homeost Agents ; 32(6): 1349-1353, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30574738

RESUMO

Exracellular matrix (ECM) consists of a plethora of proteins and polysaccharides, which aggregate into an organized network connected to the surface of the producing cells. It is structurally and functionally present in all components of tissues and organs and represents the substrate on which cells adhere, migrate, proliferate and differentiate, influencing their survival, shape and function. In response to acute (trauma) or chronic (degenerative) insults, brain ECM modifies its composition and function, actively contributing to "scar forming" gliosis or tissue degeneration/remodelling. Moreover, morphological changes in dendritic spines associated with extracellular matrix remodeling play key roles in rewiring synaptic circuitry pertinent to memory formation. In the present report, we collected the main acquisitions on the functional interplay between ECM alterations and the adenine-/guaninebased purine system with particular regard on how purine compounds and their respective receptors may affect and be affected by changes of the cerebral ECM.


Assuntos
Encéfalo/fisiologia , Sistema Nervoso Central/fisiologia , Matriz Extracelular/fisiologia , Receptores Purinérgicos/fisiologia , Humanos
8.
J Biol Regul Homeost Agents ; 32(3): 449-454, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29921369

RESUMO

The activation of brain nociceptors and neurons may lead to neurogenic inflammation, an event that involves immune cells including mast cells (MCs). Microglia are similar to macrophages and secrete pro-inflammatory IL-1 family members and TNF. TNF is rapidly released (first 10 minutes from MC granules) and is subsequently secreted along with other pro-inflammatory cytokines with a new synthesis after several hours. MC-derived TNF is a very powerful pro-inflammatory cytokine which mediates sensitization of the meningeal nociceptors. Here, we report the involvement of MCs in neuroinflammation, the role of inflammatory cytokine IL-1 family members, and of TNF, as well as the potential inhibition of IL-37.


Assuntos
Mediadores da Inflamação/imunologia , Interleucina-1/imunologia , Mastócitos/imunologia , Humanos , Inflamação/imunologia , Inflamação/patologia , Mastócitos/patologia , Neuroglia/imunologia , Neuroglia/patologia , Neurônios/imunologia , Neurônios/patologia , Nociceptores/imunologia , Nociceptores/patologia
9.
Ann Ig ; 30(3): 229-236, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29670992

RESUMO

BACKGROUND: Hand hygiene is the primary preventive measure against health care-associated infections in terms of cost-effectiveness. In 2005, the WHO proposed the "Global Patient Safety Challenge" campaign, with the aim of reducing the overall incidence of such infections, through multimodal programs and strategies, interactive training tools and standardised methods for monitoring compliance. STUDY DESIGN: On the basis of project "Rimani", sponsored by the Health and Social Care Authority of Emilia-Romagna, the Istituto Ortopedico Gaetano Pini has implemented a project which seeks to increase healthcare staff's compliance with hand hygiene. METHODS: A multidisciplinary working group was created to prepare the project documents. Starting from 5th April 2015, twenty operational units were asked to produce information and training material. On 5th May, during a conference, a committee selected the three best works. The material was distributed on a monthly basis to the various departments. In addition to the training, the specifically trained operators of the Medical Monitoring Department carried out direct hand washing tests, filling out appropriate checklists. Non-compliance relating to the technique recorded in 2014 and 2015 was compared and a statistical analysis was conducted using Student's t-test for paired data. RESULTS: Three tests were carried out in 2014. Ninety-nine cases were monitored and 5 non-compliance cases were reported, concerning the execution of the procedural steps, the running time and closing the tap with one's hands at the end of the wash. In 2015 two tests, involving 30 operational units, were carried out. 60 observations were performed, and no non-conformities emerged concerning the technique. Statistical analysis showed a significant reduction of non-compliances between the 2014 and 2015 P = 0.000). CONCLUSION: The results obtained agree with the main findings in literature. The comparison between the 2014 and 2015 tests shows a trend of improvement in the wash technique. This confirms the effectiveness of a multidisciplinary approach and recognises the active and participatory involvement suggested by the WHO.


Assuntos
Infecção Hospitalar/prevenção & controle , Higiene das Mãos , Desinfecção , Fidelidade a Diretrizes , Desinfecção das Mãos/métodos , Higiene das Mãos/normas , Pessoal de Saúde , Hospitais Especializados , Humanos , Controle de Infecções/métodos , Itália , Ortopedia , Avaliação de Programas e Projetos de Saúde
10.
Ann Ig ; 30(1): 66-70, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29215133

RESUMO

OBJECTIVES: A retrospective study describing syphilis epidemiological and clinical features in patients referring to an infectious diseases centre in Rome, Italy. METHODS: Between January 2011 and December 2015 demographic, behavioral and clinical data were collected from all adult patients attending the Sexually Transmitted Diseases Centre of the Teaching Hospital Umberto I in Rome. RESULTS: Overall 723 patients, 495 males and 228 females, with syphilis infection diagnosis were included. Average age 39.6 ± 13.6 years (median 38) was higher in men than women (41.1 ± 13.6 vs. 36.3 ± 13.1; p<0.001). Patients were from Italy (486 or 67.2%), EU (90 or 12.4%), rest of Europe (38 or 5.3 %), Americas (46 or 6.4%), Africa (36 or 5.0%) and Asia (27 or 3.7%). One-hundred-twenty-three (17.0%) presented primary syphilis, 43 (5.9%) secondary syphilis, 8 (1.1%) tertiary syphilis, 246 (34.0%) serological syphilis, 80 (11.1%) preceding syphilis, 56 (7.7%) gravidic syphilis and 167 (23.1%) came to the Sexually Transmitted Diseases Centre to control a preceding syphilis treatment. Fifty-six (24.6%) women were diagnosed with syphilis during their pregnancies. Among Chinese female patients, those pregnant represented 87.5%. There were 100 subjects (13.8%) simultaneously HIV+ and 623 (86.2%) HIV- patients. HIV co-infection affected more frequently men (RR 5.30; CI 2.62 - 10.72; p<0.001). In males HIV co-infection affected more frequently homosexuals (RR 11.72; CI 6.72 - 20.45; p<0.001). Overall HIV co-infection affected more frequently foreign patients, specially from the Americas (26.1%), Africa (25.7%) and Asia (22.2%). CONCLUSION: A serious problem of "gravidic syphilis" suggests the need for Public Health preventive action. Also an early diagnosis of both syphilis and HIV infection should be reinforced.


Assuntos
Sífilis/diagnóstico , Sífilis/epidemiologia , Adolescente , Adulto , Feminino , Hospitais de Ensino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Cidade de Roma/epidemiologia , Infecções Sexualmente Transmissíveis/diagnóstico , Infecções Sexualmente Transmissíveis/epidemiologia , Fatores de Tempo , Adulto Jovem
11.
J Biol Regul Homeost Agents ; 31(1): 21-28, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28337867

RESUMO

The major aim of this study is to provide a review of the research studies regarding the clinical link between alexithymia and interleukins (IL). We performed a search for the relevant literature by using search terms as "alexithymia" combined with "interleukin or IL". A total of 9 original research studies were identified and included. Alexithymia was found to be prevalent in inflammatory response and associated with inflammatory cytokines. Our review emphasized for the first time the relationships of alexithymia with inflammatory response mediated by IL-1 family members. Therefore, the screening of alexithymic traits and the administration of appropriate psychological and psychotherapeutical interventions should be integral parts of disease management programs. Supplying such interventions will probably help with prevention of the development of the disease and/or its exacerbation by improving the quality of life of alexithymic individuals.


Assuntos
Sintomas Afetivos/imunologia , Inflamação/imunologia , Interleucina-1/imunologia , Mastócitos/imunologia , Sintomas Afetivos/tratamento farmacológico , Sintomas Afetivos/fisiopatologia , Anti-Inflamatórios/uso terapêutico , Encéfalo/efeitos dos fármacos , Encéfalo/imunologia , Encéfalo/fisiopatologia , Regulação da Expressão Gênica , Humanos , Inflamação/tratamento farmacológico , Inflamação/fisiopatologia , Interleucina-1/antagonistas & inibidores , Interleucina-1/genética , Interleucina-33/genética , Interleucina-33/imunologia , Interleucina-6/genética , Interleucina-6/imunologia , Mastócitos/efeitos dos fármacos , Mastócitos/patologia , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/imunologia , Isoformas de Proteínas/antagonistas & inibidores , Isoformas de Proteínas/genética , Isoformas de Proteínas/imunologia , Psicotrópicos/uso terapêutico , Qualidade de Vida , Transdução de Sinais
12.
Oral Dis ; 23(4): 484-491, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28067970

RESUMO

OBJECTIVES: Fourier Transform Infrared microspectroscopy let characterize the macromolecular composition and distribution of tissues and cells, by studying the interaction between infrared radiation and matter. Therefore, we hypothesize to exploit this analytical tool in the analysis of inflamed pulps, to detect the different biochemical features related to various degrees of inflammation. MATERIALS AND METHODS: IR maps of 13 irreversible and 12 hyperplastic pulpitis, together with 10 normal pulps, were acquired, compared with histological findings and submitted to multivariate (HCA, PCA, SIMCA) and statistical (one-way ANOVA) analysis. The fit of convoluted bands let calculate meaningful band area ratios (means ± s.d., P < 0.05). RESULTS: The infrared imaging analysis pin-pointed higher amounts of water and lower quantities of type I collagen in all inflamed pulps. Specific vibrational markers were defined for irreversible pulpitis (Lipids/Total Biomass, PhII/Total Biomass, CH2 /CH3 , and Ty/AII) and hyperplastic ones (OH/Total Biomass, Collagen/Total Biomass, and CH3 Collagen/Total Biomass). CONCLUSION: The study confirmed that FTIR microspectroscopy let discriminate tissues' biological features. The infrared imaging analysis evidenced, in inflamed pulps, alterations in tissues' structure and composition. Changes in lipid metabolism, increasing amounts of tyrosine, and the occurrence of phosphorylative processes were highlighted in irreversible pulpitis, while high amounts of water and low quantities of type I collagen were detected in hyperplastic samples.


Assuntos
Polpa Dentária/metabolismo , Pulpite/diagnóstico , Espectroscopia de Infravermelho com Transformada de Fourier , Adulto , Biomarcadores/metabolismo , Estudos de Casos e Controles , Polpa Dentária/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Pulpite/metabolismo , Pulpite/patologia
13.
Phys Rev Lett ; 117(18): 183902, 2016 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-27834998

RESUMO

We report the direct observation of the onset of turbulence in propagating one-dimensional optical waves. The transition occurs as the disordered hosting material passes from being linear to one with extreme nonlinearity. As the response grows, increased wave interaction causes a modulational unstable quasihomogeneous flow to be superseded by a chaotic and spatially incoherent one. Statistical analysis of high-resolution wave behavior in the turbulent regime unveils the emergence of concomitant rogue waves. The transition, observed in a photorefractive ferroelectric crystal, introduces a new and rich experimental setting for the study of optical wave turbulence and information transport in conditions dominated by large fluctuations and extreme nonlinearity.

14.
Analyst ; 141(3): 731-9, 2016 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-26646435

RESUMO

This article reviews a very recent field of noninvasive analysis of turbid media using micro-scale Spatially Offset Raman Spectroscopy - micro-SORS. The technique combines conventional SORS with microscopy concepts and represents a new imaging modality in Raman microscopy. Micro-SORS facilitates analytical capability for investigating non-destructively the chemical composition of subsurface, micrometer-scale-thick diffusely scattering layers at depths more than an order of magnitude larger than those accessible with the depth resolving power of conventional confocal Raman microscopy. Potential application areas include nondestructive subsurface analysis of painted layers in cultural heritage, characterization of stratified polymer systems, analysis of layered biological samples or forensic analysis. The article discusses the basic principles of the technique, its variants and outlines emerging applications in this rapidly evolving field.


Assuntos
Análise Espectral Raman/métodos , Método de Monte Carlo , Pintura/análise , Papel , Espalhamento de Radiação , Sementes/química , Triticum
15.
J Biol Regul Homeost Agents ; 30(1): 309-14, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27049108

RESUMO

Fourier transform infrared (FTIR) microspectroscopy is considered a useful tool in the biomedical field, for analysing in situ and at cellular level, very small areas of tissues and cells, with minimal sample preparation and without the use of stains or probes. This spectroscopic technique has been successfully applied to analyse biological samples from patients affected by tumoral pathologies, with particular attention to oral cavity lesions. In this study, we describe the application of FTIR microspectroscopy to characterize and discriminate the most recurrent benign and malignant diseases of oral cavity compartment. Infrared maps were acquired on tissues affected by the following pathologies: squamous cell carcinoma, adenoid cystic carcinoma, polymorphous low-grade adenocarcinoma, squamous dysplasia, keratocystic odontogenic tumor, radicular cyst, residual cyst, unicystic ameloblastoma, and ameloblastic fibroma, together with healthy tissue samples (used as control group). The epithelial and connective components of all samples were distinguished and submitted to multivariate analysis. The results were in agreement with histological suggestions.


Assuntos
Neoplasias Bucais/diagnóstico , Boca/patologia , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Ameloblastoma/patologia , Análise por Conglomerados , Tecido Conjuntivo/patologia , Epitélio/patologia , Humanos , Análise Multivariada
16.
Phys Rev Lett ; 114(4): 043901, 2015 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-25679894

RESUMO

We present a unified approach to the theory of multimodal laser cavities including a variable amount of structural disorder. A general mean-field theory is studied for waves in media with variable nonlinearity and randomness. Phase diagrams are reported in terms of optical power, degree of disorder, and degree of nonlinearity, tuning between closed and open cavity scenarios. In the thermodynamic limit of infinitely many modes, the theory predicts four distinct regimes: a continuous wave behavior for low power, a standard mode-locking laser regime for high power and weak disorder, a random laser for high pumped power and large disorder, and a novel intermediate regime of phase locking occurring in the presence of disorder but below the lasing threshold.

17.
Phys Rev Lett ; 115(9): 093901, 2015 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-26371654

RESUMO

Rogue waves are observed as light propagates in the extreme nonlinear regime that occurs when a photorefractive ferroelectric crystal is undergoing a structural phase transition. The transmitted spatial light distribution contains bright localized spots of anomalously large intensity that follow a signature long-tail statistics that disappears as the nonlinearity is weakened. The isolated wave events form as out-of-equilibrium response and disorder enhance the Kerr-saturated nonlinearity at the critical point. Self-similarity associable to the individual observed filaments and numerical simulations of the generalized nonlinear Schrödinger equation suggests that dynamics of soliton fusions and scale invariance can microscopically play an important role in the observed rogue intensities and statistics.

18.
Analyst ; 140(24): 8127-33, 2015 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-26526114

RESUMO

We compare several basic embodiments of a recently proposed and demonstrated micrometer-scale Spatially Offset Raman Spectroscopy (micro-SORS). Micro-SORS is a recently introduced analytical method for noninvasive characterisation of the chemical composition of subsurface, micrometre-scale-thick diffusely scattering layers at depths beyond the reach of conventional confocal Raman microscopy. The technique is applicable, for example, in nondestructive subsurface analysis of highly scattering stratified matrices such as painted layers in cultural heritage or in noninvasive analysis of stratified polymer systems or biological samples. Using Monte Carlo simulations, we analysed two defocusing variants of micro-SORS and a variant involving a full separation of illumination and collection zones on the sample surface. Both the penetration depth into the sample and relative enhancement of sublayer Raman signals were studied as a function of layer thickness and type of technique and their parameters. The model predicts that the most effective method by far is the variant with fully spatially separated illumination and collection zones. On the other hand, the defocusing micro-SORS, where both the laser and Raman collection zones are defocussed and overlapped, yielded the lowest performance although its key benefit lies in its simplicity as the concept can be practiced on existing conventional Raman microscopes without any modifications. A basic experimental verification of the theoretical findings contrasting two extreme modalities, the fully separated micro-SORS variant with the defocusing one, is also presented.


Assuntos
Análise Espectral Raman , Microscopia Confocal , Método de Monte Carlo
19.
Nanotechnology ; 26(36): 365601, 2015 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-26292084

RESUMO

Tungsten oxide nanowires have been synthesized by vacuum annealing in the range 500-710 °C from amorphous-like tungsten films, deposited on a Si(100) substrate by pulsed laser deposition (PLD) in the presence of a He background pressure. The oxygen required for the nanowires formation is already adsorbed in the W matrix before annealing, its amount depending on deposition parameters. Nanowire crystalline phase and stoichiometry depend on annealing temperature, ranging from W18O49-Magneli phase to monoclinic WO3. Sufficiently long annealing induces the formation of micrometer-long nanowires, up to 3.6 µm with an aspect ratio up to 90. Oxide nanowire growth appears to be triggered by the crystallization of the underlying amorphous W film, promoting their synthesis at low temperatures.

20.
Ann Ig ; 27(6): 808-13, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26835795

RESUMO

BACKGROUND: Health-care associated infections (HAIs) represents a phenomenon of central importance all over Europe. Every year 4,5 millions cases are detected in European Union, with 37.000 related deaths. Surgical-site infections (SSIs) are one of the most common HAIs, that are associated with an increased length of stay, re-operation rate, intensive care admissions rate, and higher mortality rate. METHODS: G. Pini Orthopedics Institute implemented in the last two years a multimodal strategy for controlling and preventing HAIs, in particular for SSIs. RESULTS: This paper describes the prevention's strategies adopted for prevention of HAIs, at G. Pini Orthopedic Institute. CONCLUSIONS: Our findings show that application of a multi modal promotion strategy was associated with an improvement in HAI prevention.


Assuntos
Artroplastia/estatística & dados numéricos , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/prevenção & controle , União Europeia/estatística & dados numéricos , Fidelidade a Diretrizes , Ortopedia , Artroplastia/mortalidade , Cuidados Críticos/estatística & dados numéricos , Infecção Hospitalar/mortalidade , Humanos , Incidência , Itália/epidemiologia , Tempo de Internação/estatística & dados numéricos , Admissão do Paciente/estatística & dados numéricos , Vigilância da População , Guias de Prática Clínica como Assunto , Reoperação/estatística & dados numéricos , Medição de Risco , Fatores de Risco , Taxa de Sobrevida , Centros de Traumatologia
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