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1.
PLoS One ; 18(6): e0287513, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37352316

RESUMO

The study of the electroencephalogram signals recorded from subjects during an experience is a way to understand the brain processes that underlie their physical and emotional involvement. Such signals have the form of time series, and their analysis could benefit from applying techniques that are specific to this kind of data. Neuroaesthetics, as defined by Zeki in 1999, is the scientific approach to the study of aesthetic perceptions of art, music, or any other experience that can give rise to aesthetic judgments, such as liking or disliking a painting. Starting from a proprietary dataset of 248 trials from 16 subjects exposed to art paintings, using a real ecological context, this paper analyses the application of a novel symbolic machine learning technique, specifically designed to extract information from unstructured data and to express it in form of logical rules. Our purpose is to extract qualitative and quantitative logical rules, to relate the voltage at specific frequencies and in specific electrodes, and that, within the limits of the experiment, may help to understand the brain process that drives liking or disliking experiences in human subjects.


Assuntos
Beleza , Emoções , Humanos , Encéfalo , Estética , Julgamento
3.
Phys Rev Lett ; 126(17): 173903, 2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33988397

RESUMO

Frequency combs have become a prominent research area in optics. Of particular interest as integrated comb technology are chip-scale sources, such as semiconductor lasers and microresonators, which consist of resonators embedding a nonlinear medium either with or without population inversion. Such active and passive cavities were so far treated distinctly. Here we propose a formal unification by introducing a general equation that describes both types of cavities. The equation also captures the physics of a hybrid device-a semiconductor ring laser with an external optical drive-in which we show the existence of temporal solitons, previously identified only in microresonators, thanks to symmetry breaking and self-localization phenomena typical of spatially extended dissipative systems.

4.
Int J Tuberc Lung Dis ; 24(2): 196-201, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-32127104

RESUMO

SETTING: QuantiFERON TB assay (QFT) is used to screen tuberculosis (TB) infection, but it cannot distinguish active TB from latent TB infection (LTBI).OBJECTIVE: To evaluate the quantitative expression of the high-affinity FCgamma receptor I (CD64) on neutrophils (NE) and monocytes (MO) in peripheral blood using flow cytometry, measured in antibody binding capacity (ABC) units as a predictive biomarker of TB.DESIGN: Fifty-two patients were enrolled (45 QFT-positive and 7 QFT-indeterminate). Cultures and molecular analyses were performed.RESULTS: Of the 45 QFT-positive patients, 29 were culture-positive (active TB) and 16 were negative (LTBI). The median NE CD64 ABC and MO CD64 ABC expression was significantly higher (P < 0.001) in culture-positive patients. The NE CD64 and MO CD64 area under the receiver operating characteristic curve values were respectively 0.948 (95%CI 0.838-0.992) and 0.989 (0.901-1.000). By setting the cut-off NE CD64 value at >2400 ABC or MO CD64 value >25 800 the assay sensitivity increased to 95.5% with 100% specificity and 100% positive predictive value. In the QFT-indeterminate group, five culture-positive cases had NE CD64 >2400 ABC or MO CD64 value >25 800; two culture-negative cases had lower values.CONCLUSION: The CD64 quantitative expression on peripheral blood cells may be used as a predictive biomarker for active TB.


Assuntos
Tuberculose Latente , Tuberculose , Biomarcadores , Humanos , Monócitos , Neutrófilos , Receptores de IgG , Teste Tuberculínico , Tuberculose/diagnóstico
5.
Opt Express ; 27(21): 30233-30248, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31684273

RESUMO

We investigate parametric down-conversion in a hexagonally poled nonlinear photonic crystal, pumped by a dual pump with a transverse modulation that matches the periodicity of the χ (2) nonlinear grating. A peculiar feature of this resonant configuration is that the two pumps simultaneously generate photon pairs over an entire branch of modes, via quasi-phase matching with both fundamental vectors of the reciprocal lattice of the nonlinearity. The parametric gain of these modes depends thus coherently on the sum of the two pump amplitudes and can be controlled by varying their relative intensities and phases. We find that a significant enhancement of the source conversion efficiency, comparable to that of one-dimensionally poled crystals, can be achieved by a dual symmetric pump. We also show how the four-mode coupling arising among shared modes at resonance can be tailored by changing the dual pump parameters.

7.
Adv Exp Med Biol ; 977: 155-161, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28685440

RESUMO

Aging is associated with changes in biological functions, such as reduced cardiovascular responses to stressful tasks. However, less is known about the influence of age on the reactivity of the prefrontal cortex (PFC) to acute stressors. Therefore, this study aimed to investigate the effects of a computerized-controlled stress task on the PFC and autonomic system activity in a sample of older and younger adults. We recruited a total of 55 healthy, right-handed persons (26 older adults with mean age 69.5, SD 5.8 years; and 29 younger adults with mean age 23.8, SD 3.3 years); groups were balanced for sex. Tasks included a control and an experimental condition: during both tasks individuals had to solve simple mental arithmetic problems. For the experimental condition, all participants were faced with a time limit that induced significant stress. Physiological indexes were collected continuously during the entire procedure using a 2-channel near infrared spectroscopy (NIRS) and an ECG monitoring system. Repeated measures ANOVA were used to assess changes in hemoglobin concentrations, and changes in both heart rate and performance outcomes. NIRS, ECG and performance data showed a significant interaction between the group and condition. Post-hoc analyses evidenced a significant increase in heart rate and Oxy-Hb concentration in the bilateral PFC between the control and experimental condition only in the younger group. Post-hoc analyses of behavioral data showed lower percentages of correct responses and higher response times in the older group. In summary, these results suggested that cardiovascular and cortical reactivity to stress tasks are a function of age. Older individuals seem to be characterized by blunted physiological reactivity, suggestive of impaired adaptive responses to acute stressors. Therefore, future studies should investigate the underlying physiological mechanisms of prefrontal and cardiovascular changes related to aging.


Assuntos
Envelhecimento/psicologia , Frequência Cardíaca/fisiologia , Tempo de Reação/fisiologia , Estresse Psicológico/fisiopatologia , Estresse Psicológico/psicologia , Adulto , Idoso , Envelhecimento/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Córtex Pré-Frontal/fisiologia , Distribuição Aleatória , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Adulto Jovem
8.
Occup Med (Lond) ; 67(1): 64-67, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27694373

RESUMO

BACKGROUND: Mixed cryoglobulinemia (MC) is a rare multisystem disease whose aetiopathogenesis is not completely understood. Hepatitis C virus (HCV) infection may have a causative role, and genetic and/or environmental factors may also contribute. AIMS: To investigate the presence and possible role of environmental agents in MC. METHODS: We recruited 30 HCV-infected MC patients with different clinical manifestations and a control group of 30 healthy, sex-/age-matched volunteers. We collected serum samples from each patient and incubated at 4°C for 7 days to obtain cryoprecipitate samples. We used environmental scanning electron microscopy (ESEM) and energy dispersive X-ray spectroscopy microanalysis to verify the presence of microparticles (MPs) and nanoparticles (NPs) in serum and cryoprecipitate samples. We evaluated environmental exposure using a medical and occupational history questionnaire for each subject. RESULTS: MC patients had a significantly higher risk of occupational exposure (OR 5.6; 95% CI 1.84-17.50) than controls. ESEM evaluation revealed a significantly higher concentration, expressed as number of positive spots (NS), of serum inorganic particles in MC patients compared with controls (mean NS 18, SD = 16 versus NS 5.4, SD = 5.1; P < 0.05). Cryoprecipitate samples of MC patients showed high concentrations of inorganic particles (mean NS 49, SD = 19). We found a strong correlation between NS and cryocrit (i.e. percentage of cryoprecipitate/total serum after centrifugation at 4°C) levels (P < 0.001). CONCLUSIONS: In addition to HCV infection, MPs and NPs might play an important role in the aetiopathogenesis of MC.


Assuntos
Crioglobulinemia/fisiopatologia , Nanopartículas/análise , Fatores de Virulência/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Crioglobulinemia/sangue , Crioglobulinemia/diagnóstico , Feminino , Hepacivirus/patogenicidade , Hepatite C/sangue , Hepatite C/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade
9.
Leuk Res ; 50: 50-56, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27669365

RESUMO

The increase in the incidence of acute myeloid leukemia (AML) may suggest a possible environmental etiology. PM2.5 was declared by IARC a Class I carcinogen. No report has focused on particulate environmental pollution together with AML. The study investigated the presence and composition of particulate matter in blood with a Scanning Electron Microscope coupled with an Energy Dispersive Spectroscope, a sensor capable of identifying the composition of foreign bodies. 38 peripheral blood samples, 19 AML cases and 19 healthy controls, were analyzed. A significant overload of particulate matter-derived nanoparticles linked or aggregated to blood components was found in AML patients, while almost absent in matched healthy controls. Two-tailed Student's t-test, MANOVA and Principal Component Analysis indicated that the total numbers of aggregates and particles were statistically different between cases and controls (MANOVA, P<0.001 and P=0.009 respectively). The particles detected showed to contain highly-reactive, non-biocompatible and non-biodegradable metals; in particular, micro- and nano-sized particles grouped in organic/inorganic clusters, with statistically higher frequency of a subgroup of elements in AML samples. The demonstration, for the first time, of an overload of nanoparticles linked to blood components in AML patients could be the basis for a possible, novel pathogenetic mechanism for AML development.


Assuntos
Poluentes Ambientais/efeitos adversos , Leucemia Mieloide Aguda/etiologia , Nanopartículas/efeitos adversos , Análise Química do Sangue , Estudos de Casos e Controles , Poluentes Ambientais/sangue , Feminino , Humanos , Leucemia Mieloide Aguda/epidemiologia , Masculino , Metais/sangue , Nanopartículas/análise
10.
Environ Toxicol ; 31(5): 509-19, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-25358123

RESUMO

Metal-based nanoparticles (NPs), are currently used in many application fields including consumer products, pharmaceuticals, and biomedical treatments. In spite to their wide applications, an in-depth study of their potential toxic effects is still lacking. The aim of the present research was to investigate the potential initiator or promoter-like activity of different metallic NPs such as gold, iron, cobalt, and cerium using the Balb/3T3 two-stage transformation assay. The results indicated that all the selected metallic NPs, except for cobalt, when used as initiators did not induce any transformation in Balb/3T3 cell line. Moreover, Au and Fe3 O4 NPs, when used in place of the tumor promoter treatment TPA, increased significantly the number of Foci/dish as compared to the MCA treatment alone. The number of Foci/dish was 2.6 for Au NPs and 2.13 for Fe3 O4 ones, similar to those obtained by the positive control treatment (MCA + TPA), whereas 1.27 for MCA treatment alone. On the contrary, CeO2 NPs did not show any difference in the number of Foci/dish, as compared to MCA alone, but it decreased the number of foci by 65% in comparison to the positive control (MCA + TPA). As expected, cobalt NPs showed an increased cytotoxicity and only a few surviving cells were found at the time of analysis showing a number of Foci/dish of 0.13. For the first time, our data clearly showed that Au and Fe3 O4 NPs act as promoters in the two stage transformational assay, suggesting the importance to fully investigate the NPs carcinogenic potential with different models.


Assuntos
Carcinógenos/toxicidade , Transformação Celular Neoplásica/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Células 3T3 , Animais , Carcinógenos/química , Sobrevivência Celular/efeitos dos fármacos , Cério/química , Óxido Ferroso-Férrico/química , Ouro/química , Nanopartículas Metálicas/química , Metilcolantreno/toxicidade , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica , Acetato de Tetradecanoilforbol/toxicidade
11.
J Inorg Biochem ; 150: 9-17, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26047528

RESUMO

Acylhydrazones are very versatile ligands and their coordination properties can be easily tuned, giving rise to metal complexes with different nuclearities. In the last few years, we have been looking for new pharmacophores able to coordinate simultaneously two metal ions, because many enzymes have two metal ions in the active site and their coordination can be a successful strategy to inhibit the activity of the metalloenzyme. As a part of this ongoing research, we synthesized the acylhydrazone H2L and its complexes with Mg(II), Mn(II), Co(II), Ni(II), Cu(II) and Zn(II). Their characterization, both in solution--also by means of potentiometric studies--and in the solid state, evidenced the ability of the o-vanillin hydrazone scaffold to give rise to different types of metal complexes, depending on the metal and the reaction conditions. Furthermore, we evaluated both the free ligand and its metal complexes in in vitro studies against a panel of diverse DNA- and RNA-viruses. In particular, the Mg(II), Mn(II), Ni(II) and Zn(II) complexes had EC50 values in the low micromolar range, with a pronounced activity against vaccinia virus.


Assuntos
Antivirais/farmacologia , Quelantes/farmacologia , Complexos de Coordenação/farmacologia , Hidrazonas/farmacologia , Salicilamidas/farmacologia , Animais , Antivirais/síntese química , Antivirais/química , Quelantes/síntese química , Quelantes/química , Chlorocebus aethiops , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Cristalografia por Raios X , Vírus de DNA/efeitos dos fármacos , Cães , Células HeLa , Humanos , Hidrazonas/síntese química , Hidrazonas/química , Ligantes , Magnésio/química , Metais Pesados/química , Potenciometria , Vírus de RNA/efeitos dos fármacos , Salicilamidas/síntese química , Salicilamidas/química , Células Vero
12.
J R Army Med Corps ; 161(2): 153-5, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25428137

RESUMO

A 38-year-old non-commissioned officer was certified unfit for military duty several months before his death. The forensic autopsy revealed a severe bone marrow aplasia and a pulmonary angioinvasive aspergillosis. Moreover, the presence of inorganic foreign particles in the pulmonary macrophages and intestinal endothelia was observed. The microanalysis implemented on these last selected specimens revealed the presence of silica particles microimpregnated by lanthanides and steel. The patient's acquired immunodeficiency appears comparable with that of Iraqi civilians suffering from Gulf War illness. This is the first report in the literature of the presence of intestinal endothelia engulfed by foreign war particulates; the silica particles may have entered the intestinal endothelia via the blood stream or by ingestion of impregnated fruit and vegetable foodstuffs. This finding provides new perspectives in the assessment of war-associated diseases and includes electron probe microanalysis among the new techniques of military and forensic medicine.


Assuntos
Síndromes de Imunodeficiência/diagnóstico , Síndrome do Golfo Pérsico/diagnóstico , Adulto , Autopsia , Medula Óssea/patologia , Síndrome de Fadiga Crônica/diagnóstico , Humanos , Masculino , Militares
13.
Ann Ig ; 26(4): 367-79, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25001126

RESUMO

BACKGROUND: Evidence on pain management highlights the importance of a multidisciplinary approach in order to achieve optimal therapeutic results. Such programs can be guaranteed by the Centers for Pain Management (CPMs), in which multidisciplinary teams are able to provide advanced and specialized activities for the assessment, diagnosis and treatment of chronic benign pain. To date, information related to healthcare supply and the organizational structure of these centers in Italy is incomplete. The aim of this paper was to provide an overview of the healthcare network of the CPMs in the Lazio region. METHODS: A descriptive survey was conducted in all the 37 CPMs existing in the Lazio region in 2011 of which 28 participated. RESULTS: CPMs were located either in Universities or in public or private hospital facilities. They included a clinic, a Day Hospital service, Day surgery and day-beds. CPMs were managed by anaesthesiologists who, in most instances, did not work in a multidisciplinary team. The number of other health professionals available, such as nurses, psychologists and physiotherapists, was limited. CPMs mainly provided drug therapy, Complementary Alternative Medicine (CAM) and complex interventional treatments. The median waiting time was 30 days. The clinics were not homogeneously distributed in the region with a higher concentration in Rome (56%), followed by other provinces of the Lazio region (26%) and the province of Rome (18%). Clearly, Rome was the city which offered the greatest range of healthcare services and the highest number of consultations with patients, which significantly differed from those of the other areas (χ²=19.6 p<0.01). CONCLUSIONS: In 2011, the availability of CPMs was not equally distributed throughout the territory, and there was an over-utilization of the facilities in Rome and an under-utilization in the provincial areas. Moreover, this study showed a lack of a multi-professional approach to chronic pain management.


Assuntos
Clínicas de Dor/organização & administração , Humanos , Itália
14.
Braz J Biol ; 74(3 Suppl 1): S64-9, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25627367

RESUMO

The Brazilian cerrado presents strong climate seasonality. During the dry season, plants may be exposed to stressful situations, such as a soil surface water deficit, that stimulate their chemical defenses. However, the seasonality effect on the production of allelopathic compounds of cerrado plant species is poorly understood. In this study, the phytotoxic activities of common native cerrado plants were evaluated during rainy and dry seasons. Crude leaves extracts (10% concentration: weight/volume, with dry leaves and distilled water) from eleven species were tested on lettuce and sesame germination. The negative effects on germination percentages, rates and informational entropies of the target species were higher when submitted to plant extracts from the dry season, where the germination rate was the most sensible parameter. The higher sensibility of lettuce and the germination rate parameter showed this difference. Only two exceptions had higher effects for rainy season extracts; one species showed higher negative effects on germination informational entropy of lettuce and another species on the germination rate of sesame. Thus, increases in the allelopathic activity were seen in the majority of the studied cerrado plant species during the dry season. These distinct responses to stressful situations in a complex environment such as the Brazilian cerrado may support the establishment and survival of some species.


Assuntos
Alelopatia/fisiologia , Estações do Ano , Árvores/fisiologia , Brasil , Árvores/classificação
15.
Dermatology ; 227(1): 55-61, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24008289

RESUMO

BACKGROUND: The last melanoma staging system of the 2009 American Joint Committee on Cancer takes into account, for stage IV disease, the serum levels of lactate dehydrogenase (LDH) and the site of distant metastases. OBJECTIVE: Our aim was to compare the significance of metastatic volume, as evaluated at the time of stage IV melanoma diagnosis, with other clinical predictors of prognosis. METHODS: We conducted a retrospective multicentric study. To establish which variables were statistically correlated both with death and survival time, contingency tables were evaluated. The overall survival curves were compared using the Kaplan-Meier method. RESULTS: Metastatic volume and number of affected organs were statistically related to death. In detail, patients with a metastatic volume >15 cm(3) had a worse prognosis than those with a volume lower than this value (survival probability at 60 months: 6.8 vs. 40.9%, respectively). The Kaplan-Meier method confirmed that survival time was significantly related to the site(s) of metastases, to elevated LDH serum levels and to melanoma stage according to the latest system. CONCLUSION: Our results suggest that metastatic volume may be considered as a useful prognostic factor for survival among melanoma patients.


Assuntos
Melanoma/patologia , Melanoma/secundário , Neoplasias Cutâneas/patologia , Carga Tumoral , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Estimativa de Kaplan-Meier , L-Lactato Desidrogenase/sangue , Masculino , Melanoma/sangue , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Curva ROC , Estudos Retrospectivos , Neoplasias Cutâneas/sangue , Taxa de Sobrevida
16.
Phys Rev Lett ; 110(8): 083901, 2013 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-23473147

RESUMO

In this Letter we present experimental results concerning the retrieval of images of absorbing objects immersed in turbid media via differential ghost imaging (DGI) in a backscattering configuration. The method has been applied, for the first time to our knowledge, to the imaging of thin black objects located inside a turbid solution in proximity of its surface. We show that it recovers images with a contrast better than standard noncorrelated direct imaging, but equivalent to noncorrelated diffusive imaging. A simple theoretical model capable of describing the basic optics of DGI in turbid media is proposed.

17.
Ig Sanita Pubbl ; 68(5): 677-96, 2012.
Artigo em Italiano | MEDLINE | ID: mdl-23223318

RESUMO

Law no. 38 of 2010 introduces for the first time protection for access to Palliative Care and Pain Management. It was interesting to evaluate the level of knowledge among health care workers at the Policlinico Tor Vergata, procedures relating to such access through the administration of a questionnaire. The questionnaire divided into a general part and the two sections (A and B) The general part concerns the health operator respect to age, gender, profession, and his role within the operating unit of the hospital. The section A and B, is to understand if the operator knows Palliative Care, and Pain Therapy, as he became aware of the two arguments, and if they have been addressed during the university courses he attended. The analysis of the data examined show a general confusion distributed evenly among all professionals. Is greater knowledge of pain therapy compared to Palliative Care.


Assuntos
Acessibilidade aos Serviços de Saúde/legislação & jurisprudência , Manejo da Dor , Cuidados Paliativos/organização & administração , Recursos Humanos em Hospital/psicologia , Adulto , Atitude do Pessoal de Saúde , Fundações , Hospitais Universitários , Humanos , Itália , Conhecimento , Corpo Clínico Hospitalar/psicologia , Recursos Humanos de Enfermagem Hospitalar/psicologia , Cuidados Paliativos/legislação & jurisprudência , Direitos do Paciente/legislação & jurisprudência , Estudantes de Enfermagem/psicologia , Inquéritos e Questionários
18.
Phys Rev Lett ; 108(25): 253904, 2012 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-23004604

RESUMO

We demonstrate the ultranarrow temporal correlation (6 fs full width half maximum) of twin beams generated by parametric down-conversion by using its reverse process, i.e., sum-frequency generation. The result relies on an achromatic imaging of a huge bandwidth of twin beams and on a careful control of their spatial degrees of freedom. The detrimental effects of spatial filtering and imperfect imaging are shown, along with the theoretical model used to describe the results.

20.
Phys Rev Lett ; 109(24): 243901, 2012 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-23368318

RESUMO

This work presents the experimental observation of the nonfactorable near-field spatiotemporal correlation of ultrabroadband twin beams generated by parametric down-conversion, in an interferometric-type experiment using sum frequency generation, where both the temporal and the spatial degrees of freedom of parametric down-conversion light are controlled with high resolution. The revealed correlation is skewed in space-time in accordance with the X structure predicted by the theory.

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