Digital contact-tracing in France: uptake by COVID-19 risk factor and by exposure risk.

BACKGROUND: Few studies have investigated the influence of COVID-19 conspiracy theories on digital contact-tracing adoption and the differentiated uptake of digital contact-tracing by COVID-19 risk factor and by exposure risk. METHODS: Using a cross-sectional survey conducted in France in November 2020 (N = 1042), we investigate the factors associated with the use of the French 'TousAntiCovid' contact-tracing application. Our independent variables of interest include COVID-19 and 'TousAntiCovid' perceptions, trust in the government, time and risk preferences and the level of adherence to COVID-19 conspiracy theories. We conduct regression analyses by COVID-19 risk factor and exposure groups. RESULTS: Among the full sample, a negative association is found between the propensity to believe in COVID-19 conspiracy theories and the use of 'TousAntiCovid'. French respondents at risk of severe COVID-19 form are more likely to use 'TousAntiCovid'. No difference in uptake is found by exposure group. Group analyses indicate that the factors associated with the uptake of digital contact-tracing differ by COVID-19 risk factor and exposure risk. CONCLUSION: Governmental communication to fight COVID-19 misinformation and to stress out the utility and data safety of 'TousAntiCovid' should be reinforced. Targeted communication campaigns should be conducted among low adoption groups and key groups in COVID-19 transmission.

Factors associated with COVID-19 vaccination intentions and attitudes in France.

OBJECTIVES: The objective of the study is to investigate the factors associated with COVID-19 vaccination intentions and attitudes in France. STUDY DESIGN: An online cross-sectional study was conducted among a representative sample of the French population between November 20th and 23rd 2020 (N = 1146). METHODS: Factors associated with the intention to get vaccinated and with COVID-19 vaccine attitudes were estimated using ordered logistic and multinomial logistic regressions, respectively. Independent variables of interest include COVID-19 and vaccine perceptions, trust, endorsement of COVID-19 conspiracy theories and time/risk preferences. RESULTS: Only 30.5% of our respondents would agree to get vaccinated against COVID-19 during the first semester of 2021 while 31.1% declare being unsure of their vaccination intentions. COVID-19 risk perceptions are associated with vaccination intentions and attitudes. Individual and collective benefits of the vaccine and the concerns over its safety are strongly associated with COVID-19 vaccination intentions and attitudes. Vaccine acceptors are more willing to take risks in the health domain compared with vaccine hesitant respondents which indicates that the COVID-19 vaccine is perceived as a greater health risk than the COVID-19 itself by some respondents. We also find a positive association between future preference and the willingness to get vaccinated. CONCLUSION: Awareness campaigns should be conducted to enhance vaccination uptake among vaccine hesitant individuals. These campaigns could highlight the positive benefit-risk balance of the COVID-19 vaccines or the short-term benefits of vaccination and should reinsure the public on the safety of the COVID-19 vaccines.

Attitudes and opinions on quarantine and support for a contact-tracing application in France during the COVID-19 outbreak.

OBJECTIVES: We aim to identify the factors associated with support and compliance with general quarantine and with the acceptability and potential use of a contact-tracing mobile phone application among French respondents. STUDY DESIGN: We conducted a cross-sectional study between April 16th and May 7th 2020 using online questionnaires. METHODS: The sample was reweighted to be representative of the French population by age and sex, region and education level. Ordered logistic, logistic and negative binomial regressions were used to estimate the factors associated with quarantine support, with the opinion on quarantine extension, with the number and type of trips outside the quarantine home and with the acceptability and potential use of a contact-tracing application. RESULTS: After reweighting, full data for regression analyses were available for 1849 respondents. Attitudes and opinions regarding quarantine are correlated with the perceived COVID-19 threat, the perceived benefits of quarantine, trust in the government, well-being during quarantine and risk preferences. Trust in the government, perceived individual health consequences in case of COVID-19 infection and time preferences are associated with the willingness to use a contact-tracing application. CONCLUSIONS: Our analysis indicates that prevention campaigns that stress the individual risk in case of infection or the benefits of quarantine could foster compliance to quarantine protocols. Remote psychological support might also promote quarantine adherence among individuals most distressed by the quarantine. Moreover, public communications should focus on restoring trust among the population as trust is strongly correlated with the willingness to use a contact-tracing application.

Compressive three-dimensional super-resolution microscopy with speckle-saturated fluorescence excitation.

Nonlinear structured illumination microscopy (nSIM) is an effective approach for super-resolution wide-field fluorescence microscopy with a theoretically unlimited resolution. In nSIM, carefully designed, highly-contrasted illumination patterns are combined with the saturation of an optical transition to enable sub-diffraction imaging. While the technique proved useful for two-dimensional imaging, extending it to three-dimensions is challenging due to the fading of organic fluorophores under intense cycling conditions. Here, we present a compressed sensing approach that allows 3D sub-diffraction nSIM of cultured cells by saturating fluorescence excitation. Exploiting the natural orthogonality of speckles at different axial planes, 3D probing of the sample is achieved by a single two-dimensional scan. Fluorescence contrast under saturated excitation is ensured by the inherent high density of intensity minima associated with optical vortices in polarized speckle patterns. Compressed speckle microscopy is thus a simple approach that enables 3D super-resolved nSIM imaging with potentially considerably reduced acquisition time and photobleaching.

Rationale for 24-hour management of dry eye disease: A review.

The symptom severity of patients with dry eye disease (DED) varies over a 24-hour period. It is typically worse upon waking than later in the morning and deteriorates towards the evening. Substantial differences in the characteristics and physical properties of the tear film, such as levels of inflammation, pH, osmolarity, volume and stability, also exist between night (sleeping) and day (waking), and over the course of the day itself. Data on diurnal variation in symptom severity and tear film characteristics have been reviewed to recommend a management strategy that supports the various needs of patients with DED over a full 24-hour period. Treatment strategies for DED must be matched to the variations in the severity of DED and to the environments that eyes are subjected to over a 24-hour period. While artificial tears are used to moisturise the ocular surface and reduce damage to the corneal epithelium during the day, gels are used at night-time; they are more viscous and have a longer ocular surface retention time than artificial tears. Several combinations of these products are currently available in tandem to support the 24-hour variation in tear film characteristics. The present review of published literature provides evidence that the approach of the daytime use of artificial tears to protect the eye from aggravating environmental factors in combination with the night-time use of gels to relieve more severe symptomatology. This, in turn, should provide optimal 'around-the-clock' DED management.

Evaluation of the effects on conjunctival tissues of Optive eyedrops over one month usage.

The objective was to compare the effect on conjunctival tissues of the repeated use, over a one-month period, of Optive compared to Hylocomod eyedrops by a population of dry eye sufferers. The rationale for the study was that among dry eye sufferers who attend eye care practices for symptomatic relief, a large number present with conjunctival anomalies evidenced by tissue staining and that conjunctival recovery is essential to their successful long term management. The hypothesis tested was that the decrease in conjunctival staining with Optive is at least as good, and possibly greater, than that with Hylocomod. The cohort population was made up of 47 subjects (11 male and 26 female) aged 42+/-16 years with at least mild dry eye symptoms and conjunctival and/or corneal staining. The population included contact lens wearers (n=26) and non-wearers (n=21). The subjects were randomly allocated to use one of the two study products; they were instructed to use the products as often as needed but at least three times a day. Conjunctival staining was rated on forced choice scales and measured objectively using digital photographs and image analysis. The findings showed that, whereas the staining at the start of the investigation was similar (p=0.318-0.664), staining after one month of use was significantly less with Optive than Hylocomod (p=0.028-0.002). The results demonstrated that the regular use of Optive over one month was significantly superior to Hylocomod in improving conjunctival status by producing a greater reduction in the staining of dry eye sufferers.

Optical trapping and spectral analysis of aerosols with a supercontiuum laser source.

We report on the optical trapping of water droplets with a supercontinuum laser source. Droplet size is determined by observing the spectrum of the on-axis backscattered light. In contrast to to monochromatic trapping, the broad spectrum of the supercontinuum covers several resonances of the first excited Mie coefficients. A minimum value of Q approximately 0.16 for the trapping efficiency is estimated.

Field enhancement in a chain of optically bound dipoles.

A one-dimensional array of dipoles, optically trapped and bound in a fringe, is considered. The coupling with the incident field is studied as a function of the number of interacting dipoles. This coupling exhibits an enhancement which collapses when the chain is too long. Two possibilities are explored to keep enhancement: shrinking the coherence and spatially phase modulating the trapping light.

[Ewing's tumor]. / La tumeur d'Ewing.

Ewing's tumor (ET) is a malignant bone tumor occurring in children and young adults. ET affects mainly bones of the central axis, and almost always involves soft tissue infiltration. The discovery of a unique genetic alteration, which is a reciprocal translocation most frequently resulting in the fusion of the EWS gene situated on chromosome 22 with the FLI-1 gene on chromosome 11, currently places ET among neuroectodermal tumors. Moreover, this translocation is a tumor-specific genetic marker at the basis of defining ET today and is used as a diagnostic and potentially prognostic tool complementary to imaging and histopathological work-up. Since the 1970 s, important progress has been made in the clinical management of ET patients. Multiagent chemotherapy in association with local treatment (surgery and/or radiation) has clearly improved outcome. The introduction of systemic treatment was justified by the frequent sub-clinical diffusion of apparently localized ET. Intensified therapeutic strategies have for the first time cured some metastatic ET patients, but at the cost of major side effects. Treatment is currently adapted as a result of a better definition of prognostic factors as well as a better assessment of its adverse effects. Improvement in global patient care and increased management of specific acute complications associated with ET (often interwoven with iatrogeneous effects) represent an important step towards improving the quality of life for ET patients as well as preventing long term complications. In the light of present studies, the majority of surviving adults today describe their health and quality of life as good. ET is a fascinating example of the progress made not only in the diagnostic and therapeutic approach to cancer but also in the comprehension of the mechanisms behind carcinogenesis, and consequently reflects the revolution of medicine over the last century.

The relationship between self-esteem and psychiatric disorders in adolescents.

OBJECTIVE: To examine the relationship between self-esteem and psychiatric disorders in adolescents. METHODS: Seventy-six adolescents (mean age: 16.02 years; range: 12-20) treated in an inpatient unit and presenting with DSM-IV psychotic disorder, depressive disorder, anxious disorder, anorexia nervosa, personality disorder, or conduct disorder were compared with a control group of 119 adolescents drawn from a normal population. All the subjects were assessed with the French translation of the Coopersmith self-esteem inventory (SEI). RESULTS: Self-esteem was significantly higher in the control than in the clinical population (P = 0.0001). Female patients showed significantly lower SEI scores than male patients. Self-esteem increased significantly after 12 weeks in patients with a first psychotic episode who responded successfully to antipsychotic drug treatment. In the clinical group, a history of suicide attempts and sexual abuse was associated with significantly lower SEI scores. Lack of boy- or girlfriend, dropping out of school, and social withdrawal were also associated with lower self-esteem. CONCLUSION: The presence of a psychiatric disorder in adolescents is associated with decreased self-esteem. This decrease in self-esteem varies according to the psychiatric disorder. Appropriate treatment can enhance self-esteem in adolescent patients.

Influence of contact lens material surface characteristics and replacement frequency on protein and lipid deposition.

The aim of the study was to quantify the influence of both contact lens material and replacement frequency on protein and lipid deposition. The following hypotheses were tested: (1) both protein and lipid interaction with contact lenses are material-dependent, and (2) the key factors are the material ionicity for the protein deposition and the material chemical composition for the lipid deposition. Three high water content contact lens materials were tested: netrafilcon A (FDA group II, Gentle Touch), etafilcon A (FDA group IV, Acuvue), and vifilcon A (FDA group IV, Focus). Contact lens spoilation was analyzed using ultraviolet spectroscopy and fluorescence spectrophotometry. The results showed that (1) significantly more proteins were deposited on the ionic materials than on the nonionic materials, and that among the ionic materials, the higher the ionicity, the higher the level of protein deposition; (2) there were significantly more surface proteins on the ionic materials after 3 months than after 1 month of wear, but no difference over time was demonstrated for the nonionic materials; and (3) significantly more lipids were deposited onto the surface of vifilcon A than etafilcon A or netrafilcon A, and the presence of vinylpyrrolidone in the vifilcon A formulation was thought to be the cause of increased deposition. The protein and lipid interactions with contact lenses were found to be material- and time-dependent. Protein attraction was found to be related to the material ionicity. The presence of vinylpyrrolidone was a key factor in the attraction of lipids.

Preocular tear film characteristics of nonwearers and soft contact lens wearers.

The aims of the current investigation were to: (1) characterize (structure, volume, and stability) the preocular tear film of contact lens wearers and nonwearers and (2) test for any difference between contact lens wearers and nonwearers and between symptomatic and asymptomatic subjects. The tear film structure and stability were tested using the Tearscope in conjunction with the biomicroscope observation system. The tear prism height, which is indicative of the tear volume, was measured with the slitlamp. The study was carried out on 239 subjects (478 eyes) who attended our clinic for contact lens fitting. Of these, 184 were habitual daily soft contact lens wearers who had not been wearing contact lenses for at least 24 h; the other 55 were noncontact lens wearers. The results obtained showed that: (1) the stability of the tear film was correlated for two eyes of the same subject; (2) the structure, volume, and stability of the preocular tear film were similar for both groups; (3) no difference in tear film stability was found between asymptomatic and symptomatic contact lens wearers, but a significant difference was found between asymptomatic and symptomatic noncontact tact wearers; and (4) the stability of the tear film was influenced by the nature of the lipid layer present at the surface of the aqueous layer; the greatest stability was achieved when the lipid layer was thick and homogeneous (amorphous pattern).

Effect of material ionicity on the performance of daily disposable contact lenses.

The surface of hydrophilic contact lenses is intrinsically hydrophobic. Biocompatibility requires the contact lens surface to be coated with a lipoproteinic biofilm produced by the ocular secretion. For daily disposable modality of wear it is essential that biocompatibility, clinically represented by good in vivo wettability and subjective acceptance, is achieved as quickly as possible following insertion, as the process needs to be repeated daily. It has been hypothesised that non-ionic materials will not achieve biocompatibility as rapidly as ionic materials owing to the latter's ability to attract high levels of adsorbed proteins. The current investigation was a double-masked crossover study that evaluated, over 1 week of wear, a new non-ionic material (Nelfilcon A) and a current ionic material (Etafilcon A) under daily disposable modality. The results obtained showed that overall, both contact lens materials achieved good in vivo tear stability over the first 30 min of wear and good subjective acceptance that remained stable over the period of wear. The results obtained demonstrate that a non-ionic material can achieve rapid biocompatibility and subjective acceptance in a similar manner to an ionic material.

Objective measurement of contact lens-induced conjunctival redness.

Ocular redness is the principal clinical sign of any inflammatory response affecting the anterior segment of the eye. The aims of the current investigation were: (1) to develop an objective method to quantify the severity and geographic distribution of redness, (2) to validate that technique by determining its precision and compare its finding to clinical rating, and (3) to apply this technique to evaluating the diurnal variation in ocular redness associated with daily and extended soft contact lens wear. The objective capture and analysis technique involved the following steps: (1) direct image formation on the CCD array of a high resolution, high sensitivity 3/4 inch Cohu camera via a Nikon Macrolens and (2) capture and image analysis with a PC-based dedicated transputer. The key steps were: filtering to accurately locate the limbus and electronic sectioning with differential intensity color analysis at fixed intervals away from the limbus. The technique gave a direct measurement of the number and size of the vessels present. The result obtained lead to the following conclusions: (1) the digitization and analysis of video recordings of the bulbar conjunctiva provide a precise measurement of the level of conjunctival redness, (2) subjective rating of low level of conjunctival redness, using an overall nine increment clinical scale, did not relate closely to the objective measurement of conjunctival redness, (3) for non-contact lens wearers, redness in the evening was similar to redness measured upon waking, and greater than redness 2 h postwaking. In contrast, in daily soft contact lens wearers, redness was maximal in the evening and greater than before insertion or during wear in the morning. In extended soft contact lens wearers, redness was maximal upon waking when it was greater than in the evening, and (4) digitization and analysis video recordings of the redness response of the bulbar conjunctiva are sufficiently sensitive clinical research tools to monitor diurnal variation of the inflammatory response of the anterior segment of the eye.

[Foreigners and naturalized French citizens: a slow social diversification (1982-1990)]. / Etrangers et francais par acquisition, une lente diversification sociale (1982-1990).

"Two decades of economic recession have brought about profound transformations in the social structure of France's working population. In this article we focused on an analysis of socioprofessional statistics from the censuses of 1982 and 1990 (the first ones to use the new terminology) as means of understanding the role and status in these developments of populations produced by immigration. The social gap between working people of foreign origin and the birthright French remains quite considerable. Nevertheless, despite the economic situation, the social homogeneity of the minority population seems to be fading. Although the great majority of working people from a foreign background are still employed in low-echelon industrial and service jobs, there is a tendency for this homogeneity to blur slightly." (SUMMARY IN ENG AND SPA)