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1.
Opt Lett ; 46(17): 4312-4315, 2021 Sep 01.
Article in English | MEDLINE | ID: mdl-34470002

ABSTRACT

Time-resolved fluorescence imaging is a key tool in biomedical applications, as it allows to non-invasively obtain functional and structural information. However, the big amount of collected data introduces challenges in both acquisition speed and processing needs. Here, we introduce a novel technique that allows to acquire a giga-voxel 4D hypercube in a fast manner while measuring only 0.03% of the dataset. The system combines two single-pixel cameras and a conventional 2D array detector working in parallel. Data fusion techniques are introduced to combine the individual 2D and 3D projections acquired by each sensor in the final high-resolution 4D hypercube, which can be used to identify different fluorophore species by their spectral and temporal signatures.


Subject(s)
Optical Imaging
2.
Opt Express ; 27(22): 31889-31899, 2019 Oct 28.
Article in English | MEDLINE | ID: mdl-31684412

ABSTRACT

Time-resolved cameras with high temporal resolution (down to ps) enable a huge set of novel applications ranging from biomedicine and environmental science to material and device characterization. In this work, we propose, and experimentally validate, a novel detection scheme for time-resolved imaging based on a compressed sampling approach. The proposed scheme unifies into a single element all the required operations, i.e. space modulation, space integration and time-resolved detection, paving the way to dramatic cost reduction, performance improvement and ease of use.

3.
Phys Rev Lett ; 122(17): 171301, 2019 May 03.
Article in English | MEDLINE | ID: mdl-31107093

ABSTRACT

The combination of multiple observational probes has long been advocated as a powerful technique to constrain cosmological parameters, in particular dark energy. The Dark Energy Survey has measured 207 spectroscopically confirmed type Ia supernova light curves, the baryon acoustic oscillation feature, weak gravitational lensing, and galaxy clustering. Here we present combined results from these probes, deriving constraints on the equation of state, w, of dark energy and its energy density in the Universe. Independently of other experiments, such as those that measure the cosmic microwave background, the probes from this single photometric survey rule out a Universe with no dark energy, finding w=-0.80_{-0.11}^{+0.09}. The geometry is shown to be consistent with a spatially flat Universe, and we obtain a constraint on the baryon density of Ω_{b}=0.069_{-0.012}^{+0.009} that is independent of early Universe measurements. These results demonstrate the potential power of large multiprobe photometric surveys and pave the way for order of magnitude advances in our constraints on properties of dark energy and cosmology over the next decade.

4.
Phys Rev Lett ; 115(5): 051301, 2015 Jul 31.
Article in English | MEDLINE | ID: mdl-26274409

ABSTRACT

We present a mass map reconstructed from weak gravitational lensing shear measurements over 139 deg2 from the Dark Energy Survey science verification data. The mass map probes both luminous and dark matter, thus providing a tool for studying cosmology. We find good agreement between the mass map and the distribution of massive galaxy clusters identified using a red-sequence cluster finder. Potential candidates for superclusters and voids are identified using these maps. We measure the cross-correlation between the mass map and a magnitude-limited foreground galaxy sample and find a detection at the 6.8σ level with 20 arc min smoothing. These measurements are consistent with simulated galaxy catalogs based on N-body simulations from a cold dark matter model with a cosmological constant. This suggests low systematics uncertainties in the map. We summarize our key findings in this Letter; the detailed methodology and tests for systematics are presented in a companion paper.

5.
Opt Express ; 23(7): 8720-30, 2015 Apr 06.
Article in English | MEDLINE | ID: mdl-25968710

ABSTRACT

Optical trapping of silver nanoplatelets obtained with a simple room temperature chemical synthesis technique is reported. Trap spring constants are measured for platelets with different diameters to investigate the size-scaling behaviour. Experimental data are compared with models of optical forces based on the dipole approximation and on electromagnetic scattering within a T-matrix framework. Finally, we discuss applications of these nanoplatelets for surface-enhanced Raman spectroscopy.

6.
Rev Mal Respir ; 28(8): e76-93, 2011 Oct.
Article in English | MEDLINE | ID: mdl-22099417

ABSTRACT

Swallowing disorders (or dysphagia) are common in the elderly and their prevalence is often underestimated. They may result in serious complications including dehydration, malnutrition, airway obstruction, aspiration pneumonia (infectious process) or pneumonitis (chemical injury caused by the inhalation of sterile gastric contents). Moreover the repercussions of dysphagia are not only physical but also emotional and social, leading to depression, altered quality of life, and social isolation. While some changes in swallowing may be a natural result of aging, dysphagia in the elderly is mainly due to central nervous system diseases such as stroke, parkinsonism, dementia, medications, local oral and oesophageal factors. To be effective, management requires a multidisciplinary team approach and a careful assessment of the patient's oropharyngeal anatomy and physiology, medical and nutritional status, cognition, language and behaviour. Clinical evaluation can be completed by a videofluoroscopic study which enables observation of bolus movement and movements of the oral cavity, pharynx and larynx throughout the swallow. The treatment depends on the underlying cause, extent of dysphagia and prognosis. Various categories of treatment are available, including compensatory strategies (postural changes and dietary modification), direct or indirect therapy techniques (swallow manoeuvres, medication and surgical procedures).


Subject(s)
Aged , Deglutition Disorders/complications , Pneumonia/etiology , Respiratory Tract Diseases/etiology , Algorithms , Deglutition Disorders/diagnosis , Deglutition Disorders/epidemiology , Deglutition Disorders/therapy , Drug-Related Side Effects and Adverse Reactions , Humans , Models, Biological , Pneumonia/diagnosis , Pneumonia/epidemiology , Prevalence , Respiratory Tract Diseases/diagnosis , Respiratory Tract Diseases/epidemiology
7.
Anal Bioanal Chem ; 401(6): 1827-37, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21725834

ABSTRACT

Natural organic materials used to prepare pharmaceutical mixtures including ointments and balsams have been characterized by a combined non-destructive spectroscopic analytical approach. Three classes of materials which include vegetable oils (olive, almond and palm tree), gums (Arabic and Tragacanth) and beeswax are considered in this study according to their widespread use reported in ancient recipes. Micro-FTIR, micro-Raman and fluorescence spectroscopies have been applied to fresh and mildly thermally aged samples. Vibrational characterization of these organic compounds is reported together with tabulated frequencies, highlighting all spectral features and changes in spectra which occur following artificial aging. Synchronous fluorescence spectroscopy has been shown to be particularly useful for the assessment of changes in oils after aging; spectral difference between Tragacanth and Arabic gum could be due to variations in origin and processing of raw materials. Analysis of these materials using non-destructive spectroscopic techniques provided important analytical information which could be used to guide further study.


Subject(s)
Balsams/chemistry , Ointments/chemistry , Spectrometry, Fluorescence/methods , Spectroscopy, Fourier Transform Infrared/methods , Spectrum Analysis, Raman/methods , Technology, Pharmaceutical/history , Gum Arabic/analysis , History, Ancient , Plant Oils/analysis , Waxes/analysis
8.
Bull Soc Pathol Exot ; 104(2): 125-34, 2011 May.
Article in French | MEDLINE | ID: mdl-21451954

ABSTRACT

A new H1N1 virus originating from swine recently emerged as the first influenza pandemic of the 21st century. On July 3, 2009, this new influenza A(H1N1) virus (S-OIV) of swine origins was identified in Réunion Island, a French overseas department located in the southern hemisphere. The present study describes the characteristics of the epidemic from July 3 to September 30, 2009. Among the 479 patients included in our study (236 males, 37.3 ± 19.0 years), 255 (53.2%) were reported to have comorbidities or risk factors (RF) for complications. Complications occurred in 160 patients (33.4%). The most common complications were bronchial hyperreactivity (52.7%), pneumonia (32.1%), and decompensation caused by comorbidity (17.9%). 111 patients (23.2%) required hospitalization. Patients aged 65 and over, accounted for 11.9% of all patients, 32.4% of hospitalized patients and 22.5% of complicated S-OIV infections. Regardless of age, comorbidity and/or RF were reported in 80.0% of complicated S-OIV infections and 91.0% of hospitalized patients. Recommendations for surveillance, prevention and policy for persons with RF, particularly respiratory disease, are justified. However, the absence of risk factors did not prevent the occurrence of complications, present in 14.3% of the cases.


Subject(s)
Emergency Service, Hospital/statistics & numerical data , Epidemics , Influenza A Virus, H1N1 Subtype , Influenza, Human/epidemiology , Adolescent , Adult , Aged , Aged, 80 and over , Antiviral Agents/therapeutic use , Bronchial Spasm/etiology , Comorbidity , Female , Hospitalization/statistics & numerical data , Humans , Influenza, Human/complications , Influenza, Human/drug therapy , Influenza, Human/virology , Male , Middle Aged , Oseltamivir/therapeutic use , Reunion/epidemiology , Risk Factors , Time Factors , Young Adult
9.
Minerva Cardioangiol ; 59(6): 569-80, 2011 Dec.
Article in English | MEDLINE | ID: mdl-19946255

ABSTRACT

Coronary flow reserve is a useful physiologic parameter providing information on coronary stenoses severity. To date, the gold standard to evaluate coronary flow reserve consists of fractional flow reserve (FFR) measurement, assessed with a pressure-wire. The FFR has a high lesion specificity, due to insensitivity to patient hemodynamic status and to coronary microvascular resistance; it shows low inter- and intraindividual variability and a well-defined, bound cut-off range values (0.75-0.80). Several reports confirmed that FFR has high reproducibility and feasibility in patients with either single- or multi-vessel coronary artery disease, or with both stable and instable coronary artery disease and that is significantly associated with patient outcome. More recently, the FFR has been used as a sensitive marker of successful percutaneous coronary intervention, since postprocedural FFR value strongly predicts patients event-free survival rate after angioplasty. Moreover, it has been demonstrated that abnormal FFR ratios can be also associated with diffused atherosclerotic coronary artery disease in the absence of unique angiographically detectable stenoses requiring revascularization. There are strong evidences supporting that the FFR provides crucial functional information that could be related with morphological endovascular ultrasound findings, with the possibility to achieve same information in a cheaper, easier and more available manner. This review will focus on the current available literature regarding coronary flow reserve quantification and its clinical validation, suggesting and highlighting its current and future clinical applications.


Subject(s)
Coronary Artery Disease/physiopathology , Coronary Stenosis/physiopathology , Fractional Flow Reserve, Myocardial , Angioplasty, Balloon, Coronary , Coronary Artery Disease/diagnosis , Coronary Artery Disease/therapy , Coronary Circulation , Coronary Stenosis/diagnosis , Coronary Stenosis/therapy , Feasibility Studies , Humans , Mathematical Computing , Reproducibility of Results , Severity of Illness Index
10.
An Sist Sanit Navar ; 33(2): 155-65, 2010.
Article in Spanish | MEDLINE | ID: mdl-20927142

ABSTRACT

BACKGROUND: The objective of this paper is to evaluate body composition and energy expenditure in women with excess body weight. METHODS: There was a non-randomized, cross-sectional study with 40 women, [26 with excess weight (G1) and 14 eutrophic (G2)]. The following evaluations were made: dietetic, anthropometric and body composition (electrical bioimpedance), physical activity (three-dimensional accelerometer) and energy expenditure, basal and resting (indirect calorimetry). RESULTS: The energy intake and physical activity did not differ between groups. The parameters of body composition were higher in G1, except total body water. There was a relationship between energy expenditure and body composition. The lean mass was the biggest determinant of energy expenditure. There was no difference in metabolic parameters between groups, but lower nutrient oxidation and increased metabolic efficiency in G1 was suggested. CONCLUSION: Excess weight was associated with body composition and energy expenditure changes that justify the accumulation of body fat.


Subject(s)
Body Composition , Energy Metabolism , Overweight/metabolism , Adult , Cross-Sectional Studies , Female , Humans
11.
Nutr Hosp ; 25(4): 622-9, 2010.
Article in Spanish | MEDLINE | ID: mdl-20694299

ABSTRACT

INTRODUCTION: The peroxisome proliferator-activated receptor gamma 2 (PPARgamma2) is an adipogenic transcription factor that influences in insulin resistance (IR) in the presence of agonists such as polyunsaturated fatty acids (PUFA). OBJECTIVE: Evaluate the influence of dietary fat in glicidic metabolism in morbidly obese women with Pro12Pro genotype in the gene PPARgamma2. METHODS: Were selected 25 women with genotype Pro12Pro. The fat intake was estimated by food records, being used for the division of groups, GA (until 30% of the total energy expenditure (TEE)) and GB (greater than 30% of the TEE). Biochemical and anthropometric evaluations were conducted in fasting, following the test meal high in n-6 PUFA and postprandial biochemical evaluations. IR and insulin sensitivity (IS) were assessed by HOMA-IR (Homeostasis Model Assessment) and QUICKI (Quantitative Insulin Sensitivity Check Index), respectively. RESULTS AND DISCUSSION: GA presented normal HOMAIR and QUICKI. GB presented higher body mass index (BMI), HOMA-IR, saturated fatty acids (SFA) and monounsaturated (MUFA) intake higher, compared with GA (p < 0.05). In GA, the MUFA intake was negatively correlated with HOMA-IR, fasting glucose and insulin, and positively with QUICKI. The fat and SFA intake contributed to the increase in body mass and IR. However, MUFA intake may have reduced the impact of high fat diet in glicidic metabolism. It is suggested that obese women with Pro12Pro genotype in the PPARgamma2 gene avoid high fat and SFA diets, prioritizing MUFA for controlling obesity and improving the IS.


Subject(s)
Blood Glucose/genetics , Blood Glucose/metabolism , Dietary Fats , Insulin Resistance/genetics , Obesity/genetics , Obesity/metabolism , PPAR gamma/genetics , Adult , Female , Genotype , Humans
12.
Nutr. hosp ; 25(4): 622-629, jul.-ago. 2010. tab, ilus
Article in Spanish | IBECS | ID: ibc-95509

ABSTRACT

Introducción: El receptor activado por proliferadores de peroxisomas (PPARγ2) es un factor de transcripción adipogénico que influye en la resistencia a la insulina (RI) en la presencia de agonistas como los ácidos grasos poliinsaturados (AGPI). Objetivo: Evaluar la influencia de la grasa de la dieta en el metabolismo glucídico de mujeres con obesidad mórbida y con el genotipo Pro12Pro en el gen PPARγ2. Métodos: Fueron seleccionadas 25 mujeres con genotipo Pro12Pro. La ingesta habitual de lípidos fue estimada por registros alimentarios, siendo utilizada para la división de los grupos, GA (hasta un 30% del valor energético total (VET)) y GB (por encima de un 30% del VET). Fueron realizadas evaluaciones bioquímicas y antropométricas en ayuno, siguiendo la comida test rica en AGPI n-6 y los análisis bioquímicos postprandiales en GA y GB. La RI y la sensibilidad a la insulina (SI) fueron evaluadas por HOMA-IR (Homeostasis Model Assessment) y QUICKI (Quantitative Insulin Sensitivity Check Index), respectivamente. Resultados y discusión: GA presentó HOMA-IR y QUICKI normales. GB presentó el índice de masa corporal (IMC), HOMA-IR, ingesta de ácidos grasos saturados (AGS) y monoinsaturados (AGMI) superiores a GA (p < 0,05). En GB, los AGMI se correlacionaron negativamente con HOMA-IR, glucosa e insulina en ayuno, y positivamente con QUICKI. Los lípidios totales y AGS contribuyeron al aumento de la masa corporal y RI. Sin embargo, los AGMI parecen reducir el impacto de la dieta hiperlipídica en el metabolismo glucídico. Se propone que mujeres obesas con el genotipo Pro12Pro en el gen PPARγ2 eviten dietas ricas en lípidos y AGS, priorizando AGMI para el control de la obesidad y mejora de la SI (AU)


Introduction: The peroxisome proliferator-activated receptor gamma 2 (PPARγ2) is an adipogenic transcription factor that influences in insulin resistance (IR) in the presence of agonists such as polyunsaturated fatty acids (PUFA). Objective: Evaluate the influence of dietary fat in glicidic metabolism in morbidly obese women with Pro12Pro genotype in the gene PPARγ2. Methods: Were selected 25 women with genotype Pro12Pro. The fat intake was estimated by food records, being used for the division of groups, GA (until 30% of the total energy expenditure (TEE)) and GB (greater than 30% of the TEE). Biochemical and anthropometric evaluations were conducted in fasting, following the test meal high in n-6 PUFA and postprandial biochemical evaluations. IR and insulin sensitivity (IS) were assessed by HOMA-IR (Homeostasis Model Assessment) and QUICKI (Quantitative Insulin Sensitivity Check Index), respectively. Results and discussion: GA presented normal HOMAIR and QUICKI. GB presented higher body mass index (BMI), HOMA-IR, saturated fatty acids (SFA) and monounsaturated (MUFA) intake higher, compared with GA (p < 0.05). In GA, the MUFA intake was negatively correlated with HOMA-IR, fasting glucose and insulin, and positively with QUICKI. The fat and SFA intake contributed to the increase in body mass and IR. However, MUFA intake may have reduced the impact of high fat diet in glicidic metabolism. It is suggested that obese women with Pro12Pro genotype in the PPARγ2 gene avoid high fat and SFA diets, prioritizing MUFA for controlling obesity and improving the IS (AU)


Subject(s)
Humans , Female , Dietary Fats/metabolism , Obesity, Morbid/metabolism , PPAR gamma/genetics , Carbohydrate Metabolism , Genotype , Insulin Resistance
13.
Minerva Cardioangiol ; 58(1): 147-52, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20145601

ABSTRACT

The authors report, for the first time, immediate and mid-term outcome of early antiplatelet therapy discontinuation followed by uneventful non-cardiac surgery and endovascular aortic repair, few days after successful deployment of an endothelial progenitor cell capturing coronary stent, in three consecutive patients.


Subject(s)
Coronary Vessels , Endothelial Cells , Preoperative Care , Stem Cells , Stents , Aged , Humans , Male , Middle Aged , Platelet Aggregation Inhibitors/administration & dosage , Time Factors
14.
Rev Mal Respir ; 26(6): 587-605, 2009 Jun.
Article in French | MEDLINE | ID: mdl-19623104

ABSTRACT

Swallowing disorders (or dysphagia) are common in the elderly and their prevalence is often underestimated. They may result in serious complications including dehydration, malnutrition, airway obstruction, aspiration pneumonia (infectious process) or pneumonitis (chemical injury caused by the inhalation of sterile gastric contents). Moreover the repercussions of dysphagia are not only physical but also emotional and social, leading to depression, altered quality of life, and social isolation. While some changes in swallowing may be a natural result of aging, dysphagia in the elderly is mainly due to central nervous system diseases such as stroke, parkinsonism, dementia, medications, local oral and oesophageal factors. To be effective, management requires a multidisciplinary team approach and a careful assessment of the patient's oropharyngeal anatomy and physiology, medical and nutritional status, cognition, language and behaviour. Clinical evaluation can be completed by a videofluoroscopic study which enables observation of bolus movement and movements of the oral cavity, pharynx and larynx throughout the swallow. The treatment depends on the underlying cause, extent of dysphagia and prognosis. Various categories of treatment are available, including compensatory strategies (postural changes and dietary modification), direct or indirect therapy techniques (swallow manoeuvres, medication and surgical procedures).


Subject(s)
Deglutition Disorders/complications , Pneumonia, Aspiration/etiology , Respiratory Tract Infections/prevention & control , Aged , Anti-Bacterial Agents/therapeutic use , Deglutition Disorders/diagnosis , Deglutition Disorders/etiology , Deglutition Disorders/therapy , Fluoroscopy , Humans , Pneumonia, Aspiration/epidemiology , Pneumonia, Aspiration/therapy , Respiratory Tract Infections/etiology
15.
Nanotechnology ; 20(24): 245606, 2009 Jun 17.
Article in English | MEDLINE | ID: mdl-19471080

ABSTRACT

An effective method for the production of surface enhanced Raman scattering (SERS) active substrates is presented. Nanostructured silver thin films are pulsed laser deposited in an argon atmosphere. The films consist of arrays of nanoparticles whose size is controlled by the Ar pressure. The surface morphology of the films can be tuned by the laser pulse number. Nanoparticle size is calculated by a phenomenological model taking into account the dynamics of the laser generated silver plasma. The SERS activity of the films is investigated by Raman scattering of adsorbed rhodamine 6G at different concentrations.


Subject(s)
Crystallization/methods , Lasers , Nanostructures/chemistry , Nanostructures/ultrastructure , Nanotechnology/methods , Silver/chemistry , Spectrum Analysis, Raman/methods , Macromolecular Substances/chemistry , Materials Testing , Molecular Conformation , Particle Size , Surface Properties
16.
Appl Spectrosc ; 62(5): 569-74, 2008 May.
Article in English | MEDLINE | ID: mdl-18498699

ABSTRACT

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.


Subject(s)
Wood/chemistry , Glass , Plastics , Spectrophotometry, Infrared/methods , Spectrum Analysis/methods , Time Factors , Wood/analysis
18.
Opt Express ; 14(5): 1888-98, 2006 Mar 06.
Article in English | MEDLINE | ID: mdl-19503518

ABSTRACT

We have devised and experimentally validated, on tissue-simulating phantoms and in vivo, a time-resolved spectral fitting analysis for direct assessment of chromophore concentrations and scattering parameters. Experimental data have been acquired with a time-resolved broadband system based on supercontinuum light generated in a photonic crystal fiber and a 32 channel Time Correlated Single Photon Counting system. The novel method is more robust than conventional techniques, especially at low signal-to-noise ratio.

19.
Opt Express ; 13(25): 10075-84, 2005 Dec 12.
Article in English | MEDLINE | ID: mdl-19503220

ABSTRACT

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.

20.
J Photochem Photobiol B ; 60(2-3): 73-8, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11470561

ABSTRACT

Time-resolved reflectance spectroscopy was performed on tumor-bearing mice, administered with disulphonated aluminum phthalocyanine (AlS(2)Pc, 5 mg/kg body weight), before, during and after photodynamic therapy. This allowed us to evaluate the absorption spectrum of AlS(2)Pc in vivo from 610 to 700 nm, and to investigate how the therapeutic irradiation affects it. Two tumor locations (intraderma on the back and intramuscular in the leg), and two uptake times (3 and 12 h) were considered. As already observed previously, the absorption spectrum of AlS(2)Pc in vivo is centered at 680-685 nm. The irradiation causes a blue-shift of the measured line shape, more or less marked depending on the experimental conditions. A reduction in absorption is also often observed upon illumination with therapeutic light doses.


Subject(s)
Fibrosarcoma/drug therapy , Indoles/pharmacokinetics , Organometallic Compounds/pharmacokinetics , Photochemotherapy , Radiation-Sensitizing Agents/pharmacokinetics , Absorption/radiation effects , Animals , Cytosol/metabolism , Disease Models, Animal , Fibrosarcoma/virology , Indoles/therapeutic use , Lysosomes/metabolism , Mice , Organometallic Compounds/therapeutic use , Radiation-Sensitizing Agents/therapeutic use , Spectrophotometry
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