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Measuring temperature in complex two-phase flows is crucial for understanding the dynamics of heat and mass transfer. In this Letter, we introduce a novel, to the best of our knowledge, optical approach based on the combination of two-photon laser-induced fluorescence (2p-LIF) imaging and two-color laser-induced fluorescence (2CLIF) for instantaneous temperature mapping of complex liquid media. Using Kiton Red (KR) and Rhodamine 560 (R560), a temperature sensitivity of 1.54 % / ∘ C has been achieved over a range of 17-60°C. The monitoring of two-dimensional transient temperature dynamics in the heating and degassing of water shows the efficiency of the 2p-2CLIF. This new approach contributes to the toolkit of optical temperature measurement techniques, providing a robust solution for studying transient scattering media and high-speed two-phase flows.

Treating severe dermal disruptions often presents significant challenges. Recent advancements have explored biological cell sprays as a promising treatment, but their success hinges on efficient cell delivery and complete wound coverage. This requires a good spray distribution with a small droplet size, high particle number, and ample surface coverage. The type of nozzle used with the spray device can impact these parameters. To evaluate the influence of different nozzles on spray characteristics, we compared air-assisted and unassisted nozzles. The unassisted nozzle displayed small particle size, high particle number, good overall coverage, high cell viability, preserved cell metabolic activity, and low cytotoxicity. Air-assisted nozzles did not perform well regarding cell viability and metabolic activity. Flow visualization analysis comparing two different unassisted nozzles using high-speed imaging (100 kHz frame rate) revealed a tulip-shaped spray pattern, indicating optimal spray distribution. High-speed imaging showed differences between the unassisted nozzles. One unassisted nozzle displayed a bi-modal distribution of the droplet diameter while the other unassisted nozzle displayed a mono-modal distribution. These findings demonstrate the critical role of nozzle selection in successful cell delivery. A high-quality, certified nozzle manufactured for human application omits the need for an air-assisted nozzle and provides a simple system to use with similar or better performance characteristics than those of an air-assisted system.

Previous research has shown that the polarization ratio technique allows the characterization of the surface mean diameter, D 21 , of droplets forming dilute sprays. However, its application to optically dense sprays has posed significant challenges due to the presence of multiple light scattering. Additionally, errors in measurement can arise from the angular dependence of the signal. In this Letter, we present a novel, to the best of our knowledge, method that addresses these challenges. Our approach combines the use of a telecentric objective with structured laser illumination, to both optimize light detection and suppress the unwanted intensity from multiple scattering. This approach enables the utilization of the polarization ratio technique for measuring the droplet size of challenging atomizing sprays. The method offers a promising solution for accurate and comprehensive spray characterization. It is applied, here, to a hollow-cone water spray running at 30, 50, and 70 bar injection pressure, reaching an optical depth up to three.

To control the evolution of a pandemic such as COVID-19, knowing the conditions under which the pathogen is being transmitted represents a critical issue, especially when implementing protection strategies such as social distancing and wearing face masks. For viruses and bacteria that spread via airborne and/or droplet pathways, this requires understanding how saliva droplets evolve over time after their expulsion by speaking or coughing. Within this context, the transition from saliva droplets to solid residues, due to water evaporation, is studied here both experimentally, considering the saliva from 5 men and 5 women, and via numerical modeling to accurately predict the dynamics of this process. The model assumes saliva to be a binary water/salt mixture and is validated against experimental results using saliva droplets that are suspended in an ultrasound levitator. We demonstrate that droplets with an initial diameter smaller than 21 μm will produce a solid residue that would be considered an aerosol of <5 μm diameter in less than 2 s (for any relative humidity less than 80% and/or any temperature greater than 20°C). Finally, the model developed here accounts for the influence of the saliva composition, relative humidity and ambient temperature on droplet drying. Thus, the travel distance prior to becoming a solid residue can be deduced. We found that saliva droplets of initial size below 80 μm, which corresponds to the vast majority of speech and cough droplets, will become solid residues prior to touching the ground when expelled from a height of 160 cm., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

Purpose: Women's sexual health and wellbeing with cervical or vaginal cancer may be largely affected by complications from external beam radiotherapy (EBRT) and utero-vaginal brachytherapy (BT), of which vaginal stenosis is the main complication. The objective of this study was to assess the impact of support by a nurse sexologist on sexuality, vaginal side-effects, and the quality of clinical follow-up in patients treated with brachytherapy for cervical or vaginal cancer., Methods: We performed a retrospective study of the sexuality of women treated for cervical or vaginal cancer. Data from patients with cervical or vaginal cancer who underwent brachytherapy between 2013 and 2017 were collected at Institut Universitaire de Cancer de Toulouse-Oncopôle (IUCT-Oncopôle). Patients were divided into two groups: group A (intervention group) received support from a nurse sexologist and group B (control group) did not. The chi-square test and a logistic multivariate model were used for data analysis., Results: A total of 156 patients were included in this study, including 57.7% who were followed by a nurse sexologist. We observed low compliance in using vaginal dilators after brachytherapy and/or radiotherapy over time regardless of the group, and patients' sexual activity was inadequately addressed. Information regarding the resumption of sexuality 2 months after treatment was missing in 1.1% of patients in group A and in 36.4% of patients in group B. Multivariate analysis showed that patients in group A had a lower risk of developing vaginal stenosis with OR crude = 0.5 (95% CI = 0.25-0.92) and OR adj . = 0.5 (95% CI = 0.26-1.09) compared with those in group B., Conclusion: This retrospective study highlights the lack of information collected by physicians during follow-up concerning the sexuality of patients with cervical or vaginal cancer treated by EBRT and BT. The support offered by nurse sexologists in improving patients' sexual activity and reducing their physical side-effects such as vaginal stenosis is likely to be beneficial. A prospective study is currently being conducted to validate the present findings.

Schizophrenia is a debilitating disease that usually begins in young adulthood, at a time when a person would usually make the transition to independent living, but it can occur at any age. The symptoms and behaviour associated with psychosis and schizophrenia have a distressing impact on the individual, and the family. The course of schizophrenia varies considerably. Although most patients will recover, some will have persisting difficulties or remain vulnerable to future episodes. Therefore, stabilisation of patients in acute phases and avoidance of relapse are major objectives of management throughout the course of this disease. The purpose of this article is to clarify the stabilisation, to study the contributing factors and strategies to implement to achieve stability, through a literature review and key guidelines. Thus, the patient is stabilised when productive symptoms and behavioural problems have decreased. So, the stable phase represents a prolonged period of treatment and rehabilitation during which symptoms are under adequate control and the focus is on improving functioning and recovery. Important predictive criteria of stabilisation include: positive symptoms, the number of previous relapses, cooperation with the patient and family, good adherence to treatment and the use of long acting injectable second-generation antipsychotics. After an acute relapse, the careful organization of the discharge and the development of a proposed ambulatory care in tailored care structures will help consolidate stabilisation and obtain remission. Accepting the idea of continuing treatment is a complex decision in which the psychiatrist plays a central role beside patients and their families. The course of integrated actions on modifiable risk factors such as psychosocial support, addictive comorbidities, identification of prodromes, active information for the therapeutic education of patients and families and access to care will also be supported. This would improve the functional abilities of patients, their social adaptation and particularly their quality of life., (Copyright © 2014 L’Encéphale, Paris. Published by Elsevier Masson SAS. All rights reserved.)