Black paints covered with multidielectrics: light absorbers.

Black paints are commonly used to provide broadband light absorbers in high-precision optics. We show how multidielectric coatings improve the performances of these absorbers. The coated rough paints still exhibit a quasi-lambertian diffuse reflection, but this scattering pattern can be reduced by several orders of magnitude, which strongly enhances absorption. Predictions are based on an exact electromagnetic theory of light scattering from arbitrary rough multilayers. Results are also compared to useful approximate theories.

Anti-scattering effect analyzed with an exact theory of light scattering from rough multilayers.

First-order theories of light scattering previously revealed the existence of anti-scattering effects in optical multilayers. Here we present an exact electromagnetic theory that is able to complete the scattering analysis when first-order scattering is cancelled. The theory is valid for arbitrary rough multilayers.

A web-based multidomain lifestyle intervention with connected devices for older adults: research protocol of the eMIND pilot randomized controlled trial.

BACKGROUND: Multidomain interventions composed of nutritional counseling, exercise and cognitive trainings have shown encouraging results as effective preventive strategies delaying age-related declines. However, these interventions are time- and resource-consuming. The use of Information and Communication Technologies (ICT) might facilitate the translation from research into real-world practice and reach a massive number of people. AIM: This article describes the protocol of the eMIND study, a randomized controlled trial (RCT) using a web-based multidomain intervention for older adults. METHODS: One hundred and twenty older adults (≥ 65 years), with a spontaneous memory complaint, will be randomly assigned to a six-month web-based multidomain (nutritional counseling, physical and cognitive trainings) intervention group with a connected accelerometer (number of steps, energy expenditure), or to a control group with access to general information on healthy aging plus the accelerometer, but no access to the multidomain intervention. The main outcome is the feasibility/acceptability of the web-based intervention. Secondary clinical outcomes include: cognitive functions, physical performance, nutritional status and cost-effectiveness. RESULTS: We expect a high amount of adherers (ie, > 75% compliance to the protocol) to reflect the feasibility. Acceptability, assessed through interviews, should allow us to understand motivators and barriers to this ICT intervention. We also expect to provide data on its effects on various clinical outcomes and efficiency. CONCLUSION AND DISCUSSION: The eMIND study will provide crucial information to help developing a future and larger web-based multidomain lifestyle RCT, which should facilitate the translation of this ICT intervention from the research world into real-life clinical practice for the healthcare of older adults.

Speckle intensity statistics for chromatic scattering media under partially polarized illumination.

Intensity contrast in a fully developed speckle pattern resulting from the elastic scattering of a partially polarized light from a strongly scattering medium is theoretically and numerically studied. Simple expressions are derived when the illumination bandwidth is much smaller or larger than the chromatic length of the scattering medium.

Enpolarization and depolarization of light scattered from chromatic complex media.

Influence of the variations of the scattering properties of a disordered medium with respect to frequency on the polarization of scattered light is investigated. We focus on the strongly scattering regime with the sum of random phasors scattering model that is extended to chromatic media and made frequency-sensitive. It is numerically shown how the scattered polarization depends on the incident polarization and the incident light bandwidth to scattering coefficients chromatic length ratio. Under the presented approach, both phenomena of depolarization and enpolarization of light appear unified.

Accurate metrology of polarization curves measured at the speckle size of visible light scattering.

An optical procedure is presented to measure at the speckle size and with high accuracy, the polarization degree of patterns scattered by disordered media. Whole mappings of polarization ratio, polarimetric phase and polarization degree are pointed out. Scattered clouds are emphasized on the Poincaré sphere, and are completed by probability density functions of the polarization degree. A special care is attributed to the accuracy of data. The set-up provides additional signatures of scattering media.

Polarization analysis of speckle field below its transverse correlation width : application to surface and bulk scattering.

An experimental method for accurate polarimetric characterization of speckle field below its transverse correlation width is proposed. Using a polarimetric analyzer, the speckle field under investigation is probed by a set of polarimetric projections describing the full Poincaré sphere surface. Spatial polarimetric variations of the speckle field are thus observed with an accuracy of 1% for each Stokes parameter. Moreover, all the experimental data can be guaranteed by a validity criterion. Using white paper sheet and rough metal samples, the method exhibits strong potential to analyze and differentiate speckle fields generated by bulk and surface scattering.

Polycystic liver in the adult (PLA) in Spain: analysis of a structured survey analyzing the experience and attitude of gastroenterologists in Spain.

BACKGROUND: Polycystic liver in the adult (PLA) is a rare disease characterized by chronic liver enlargement. OBJECTIVE: To analyse gastroenterologists´ involvement in, experience with, and attitude toward diagnosing, monitoring, andtreating patients with PLA in Spain. METHODS: Each of seven study coordinators contacted 15 specialists in their geographic area about participating in the study via an online structured survey. RESULTS: Of the 105 clinics contacted, 88 completed the questionnaire, with a mean of 3 patients being followed per practice, although 6 clinics were following more than 20 patients with PLA. Patients were being followed mainly by the Department of Hepatology (81 %) and/or the Department of Gastroenterology (33 %). The majority of patients were diagnosed (98 %) and monitored (97 %) using liver ultrasound. When diagnosed, 76 % of patients were under 50 years of age, females predominating.The primary treatment objective for the patients was symptomatic management. Pharmacotherapy was prescribed by 28 % of physicians: Somatostatin analogues, primarily, followed by mTOR inhibitors. One-third of the clinics indicated that they had patients who had undergone liver transplant and/or surgery. CONCLUSIONS: Ultrasound is the diagnosing and monitoring method of choice. Among the clinics using pharmacotherapy for symptomatic management, somatostatin analogues were the drugs of choice. These clinics´ infrequent use of invasive procedures suggests that they perceive the various invasive techniques as not very effective.

Pediatric conjunctival melanoma: A comprehensive case report and literature review.

Purpose: This case report aims to present a rare instance of conjunctival melanoma in a 5-year-old patient and contribute to the limited body of knowledge on pediatric conjunctival melanoma. The purpose is to understand the characteristics, diagnosis, and management of this uncommon malignancy in young individuals. Observations: The case describes a 5-year-old female with a progressively growing pigmented conjunctival lesion. The lesion was observed to be located on the temporal conjunctiva of the right eye and displayed distinctive features, including feeder vessels. Imaging revealed specific dimensions of the lesion and ruled out deeper invasions. Histopathological examination revealed architectural and cytologic atypia, positive immunohistochemical staining for HMB-45, and a Ki67 proliferation index of 20 %, confirming the diagnosis of conjunctival melanoma. Conclusions: Conjunctival melanoma, an uncommon malignancy even more so in pediatric patients, typically presents with pigmented growths and feeder vessels. This case underscores the need for thorough diagnosis and early intervention, as conjunctival melanoma can lead to devastating outcomes. The rarity of such cases limits our understanding of their etiology and progression. This case contributes to the literature on pediatric conjunctival melanoma and reinforces the importance of vigilance in detecting and managing ocular pigmented lesions in children.

Mapping the coherence time of far-field speckle scattered by disordered media.

The polarization and temporal coherence properties of light are altered by scattering events. In this paper, we follow a far-field approach, modelizing the scattering from disordered media with the scattering matrix formalism. The degree of polarization and coherence time of the scattered light are expressed with respect to the characteristics of the incident field.

Light enpolarization by disordered media under partial polarized illumination: the role of cross-scattering coefficients.

We show how disordered media allow to increase the local degree of polarization (DOP) of an arbitrary (partial) polarized incident beam. The role of cross-scattering coefficients is emphasized, together with the probability density functions (PDF) of the scattering DOP. The average DOP of scattering is calculated versus the incident illumination DOP.

Nanometric resolution with far-field optical profilometry.

We show experimentally that a resolution far beyond that of conventional far-field optical profilometers can be reached with optical diffraction tomography. This result is obtained in the presence of multiple scattering when using an adapted inverse scattering algorithm for profile reconstruction. This new profilometry technique, whose resolution can be compared to that of atomic microscopes, also gives access to the permittivity of the surface.

Cortico-juxtacortical involvement increases risk of epileptic seizures in multiple sclerosis.

OBJECTIVES: Previous studies have reported an increased risk for epileptic seizures in multiple sclerosis (MS) patients. However, data on the pathogenesis of seizures remain inconclusive. The aim of our study is to evaluate prevalence, clinical and paraclinical features of epileptic attacks in our MS cohort and to search MS-specific risk factors for epileptic seizures. MATERIALS AND METHODS: In this cohort of 428 MS patients, 13 patients were identified with epileptic seizures occurring at any point during the course of MS including at MS onset. As a control group, we selected 26 MS patients without seizures and matched for gender, age and date of MS onset. We compared demographic features and clinic-radiological findings between the both groups. RESULTS: Thirteen patients (3%) were identified as having epileptic attacks. Ten patients (77%) experienced focal seizures, half of whom had confirmed secondary generalization. We did not find an association between seizures and disease course. Most patients had a single or few (2-5) seizures. MS patients with seizures had a significantly higher number of cortical and juxtacortical lesions on T2-weighted/fluid attenuation inversion recovery magnetic resonance imaging than control group [OR = 2.6 CI95% (1.0-6.5); P = 0.047]. CONCLUSIONS: Our findings support a credible role of cortical and juxtacortical involvement in the development of epileptic seizures in MS.

Membrane proteins in four acts: function precedes structure determination.

Studies on four membrane protein systems, which combine information derived from crystal structures and biophysical studies have emphasized, as a precursor to crystallization, demonstration of functional activity. These assays have relied on sensitive spectrophotometric, electrophysiological, and microbiological assays of activity to select purification procedures that lead to functional complexes and with greater likelihood to successful crystallization: (I), Hetero-oligomeric proteins involved in electron transport/proton translocation. (1) Crystal structures of the eight subunit hetero-oligomeric trans-membrane dimeric cytochrome b(6)f complex were obtained from cyanobacteria using a protocol that allowed an analysis of the structure and function of internal lipids at specific intra-membrane, intra-protein sites. Proteolysis and monomerization that inactivated the complex and prevented crystallization was minimized through the use of filamentous cyanobacterial strains that seem to have a different set of membrane-active proteases. (2) An NADPH-quinone oxido-reductase isolated from cyanobacteria contains an expanded set of 17 monotopic and polytopic hetero-subunits. (II) ß-Barrel outer membrane proteins (OMPs). High resolution structures of the vitamin B(12) binding protein, BtuB, solved in meso and in surfo, provide the best example of the differences in such structures that were anticipated in the first application of the lipid cubic phase to membrane proteins [1]. A structure of the complex of BtuB with the colicin E3 and E2 receptor binding domain established a "fishing pole" model for outer membrane receptor function in cellular import of nuclease colicins. (III) A modified faster purification procedure contributed to significantly improved resolution (1.83Å) of the universal porin, OmpF, the first membrane protein for which meaningful 3D crystals have been obtained [2]. A crystal structure of the N-terminal translocation domain of colicin E3 complexed to OmpF established the role of OmpF as an import channel for colicin nuclease cytotoxins. (IV) α-Synuclein, associated with the etiology of Parkinson's Disease, is an example of a protein, which is soluble and disordered in solution, but which can assume an ordered predominantly α-helical conformation upon binding to membranes. When subjected in its membrane-bound form to a trans-membrane electrical potential, α-synuclein can form voltage-gated ion channels. Summary of methods to assay functions/activities: (i) sensitive spectrophotometric assay to measure electron transfer activities; (ii) hydrophobic chromatography to deplete lipids, allowing reconstitution with specific lipids for studies on lipid-protein interactions; (iii) microbiological screen to assay high affinity binding of colicin receptor domains to Escherichia coli outer membrane receptors; (iv) electrophysiology/channel analysis (a) to select channel-occluding ligands for co-crystallization with ion channels of OmpF, and (b) to provide a unique description of voltage-gated ion channels of α-synuclein.

Full polarization optical profilometry.

Optical digital tomographic microscopy can be used for profilometry. The profile of the surface can be estimated from measurements of the complex diffracted far field obtained when the sample is illuminated successively under various incidences. Outside the validity domain of perturbative theories of diffraction, the profile is determined by using an iterative inverse wave scattering numerical method. In this paper we show that, for perfectly conducting surfaces, the two fundamental polarization cases involve different distances of interaction in the multiple scattering phenomenon. The use of both polarization cases in the inversion process leads to a considerable improvement of the lateral resolution. Robustness to noise is also discussed.

Enpolarization of light by scattering media.

The polarization of a coherent depolarized incident light beam passing through a scattering medium is investigated at the speckle scale. The polarization of the scattered far field at each direction and the probability density function of the degree of polarization are calculated and show an excellent agreement with experimental data. It is demonstrated that complex media may confer high degree of local polarization (0.75 DOP average) to the incident unpolarized light.

Full wave optical profilometry.

We show that tomographic diffractive microscopy can be used for profilometry applications with high transverse resolution. We present an iterative reconstruction procedure, based on a rigorous wave scattering model, that permits us to retrieve the profile of rough metallic interfaces from the complex scattered field. The transversal resolution is subwavelength, and can even fall below the classical resolution limit if the profile is rough enough for multiple interactions to occur. Large profiles, with tens of wavelength size, can be investigated.

The Rhizopur process ten years on: a green solution for sewage treatment in small communities.

Ten years ago the Rhizopur process was conceived in order to treat sewage from small towns. Since 1999 when the first Rhizopuru plant was commissioned, the number of facilities has been growing steadily and today there are more than fifty Rhizopur'" facilities in France. This process combines three existing technologies, i.e. biofilm, infiltration/percolation and mineralisation in constructed wetlands, to conduct both wastewater and sludge treatment in a very cost-effective fashion. A trickling filter or a rotating biological contactor is combined with constructed wetlands to produce a high quality effluent, i.e. BOD5 <20 mg/I, COD<100 mg/I and TSS < 30 mg/I, and to achieve high removal efficiencies, i.e. BOD5 removal >90%, COD removal >80% and TSS removal >90%. Nitrification can also be achieved by increasing the size of the trickling filter. Part of the success of this process has been its modularity and compactness that have resulted in its easiness for extension, as well as its capacity to blend with the environment. The characteristics of this process make of it an appropriate solution for sewage treatment in the developing countries. The objective of this work is to give an overview of the performance and features of this process according to the operational experience gained during the last 10 years.

A Web-Based Multidomain Lifestyle Intervention for Older Adults: The eMIND Randomized Controlled Trial.

Importance/Objective: To describe the feasibility and acceptability of a 6-month web-based multidomain lifestyle training intervention for community-dwelling older people and to test the effects of the intervention on both function- and lifestyle-related outcomes. DESIGN: 6-month, parallel-group, randomized controlled trial (RCT). SETTING: Toulouse area, South-West, France. PARTICIPANTS: Community-dwelling men and women, ≥ 65 years-old, presenting subjective memory complaint, without dementia. INTERVENTION: The web-based multidomain intervention group (MIG) received a tablet to access the multidomain platform and a wrist-worn accelerometer measuring step counts; the control group (CG) received only the wrist-worn accelerometer. The multidomain platform was composed of nutritional advices, personalized exercise training, and cognitive training. Main outcomes and measures: Feasibility, defined as the proportion of people connecting to ≥75% of the prescribed sessions, and acceptability, investigated through content analysis from recorded semi-structured interviews. Secondary outcomes included clinical (eg, cognitive function, mobility, health-related quality of life (HRQOL)) and lifestyle (eg, step count, food intake) measurements. RESULTS: Among the 120 subjects (74.2 ±5.6 years-old; 57.5% women), 109 completed the study (n=54, MIG; n=55, CG). 58 MIG subjects connected to the multidomain platform at least once; among them, adherers of ≥75% of sessions varied across multidomain components: 37 people (63.8% of 58 participants) for cognitive training, 35 (60.3%) for nutrition, and three (5.2%) for exercise; these three persons adhered to all multidomain components. Participants considered study procedures and multidomain content in a positive way; the most cited weaknesses were related to exercise: too easy, repetitive, and slow progression. Compared to controls, the intervention had a positive effect on HRQOL; no significant effects were observed across the other clinical and lifestyle outcomes. CONCLUSIONS AND RELEVANCE: Providing multidomain lifestyle training through a web-platform is feasible and well-accepted, but the training should be challenging enough and adequately progress according to participants' capabilities to increase adherence. Recommendations for a larger on-line multidomain lifestyle training RCT are provided.