Airborne virus transmission under different weather conditions.

The COVID19 infection is known to disseminate through droplets ejected by infected individuals during coughing, sneezing, speaking, and breathing. The spread of the infection and hence its menace depend on how the virus-loaded droplets evolve in space and time with changing environmental conditions. In view of this, we investigate the evolution of the droplets within the purview of the Brownian motion of the evaporating droplets in the air with varying weather conditions under the action of gravity. We track the movement of the droplets until either they gravitationally settle on the ground or evaporate to aerosols of size 2 µm or less. Droplets with radii 2 µm or less may continue to diffuse and remain suspended in the air for a long time. The effects of relative humidity and temperature on the evaporation are found to be significant. We note that under strong flowing conditions, droplets travel large distances. It is found that the bigger droplets fall on the ground due to the dominance of gravity over the diffusive force despite the loss of mass due to evaporation. The smaller evaporating droplets may not settle on the ground but remain suspended in the air due to the dominance of the diffusive force. The fate of the intermediate size droplets depends on the weather conditions and plays crucial roles in the spread of the infection. These environment dependent effects indicate that the maintenance of physical separation to evade the virus is not corroborated, making the use of face masks indispensable.

Transmission of airborne virus through sneezed and coughed droplets.

The spread of COVID19 through droplets ejected by infected individuals during sneezing and coughing has been considered a matter of key concern. Therefore, a quantitative understanding of the propagation of droplets containing the virus assumes immense importance. Here, we investigate the evolution of droplets in space and time under varying external conditions of temperature, humidity, and wind flow by using laws of statistical and fluid mechanics. The effects of drag, diffusion, and gravity on droplets of different sizes and ejection velocities have been considered during their motion in air. In still air, we found that bigger droplets traverse a larger distance, but smaller droplets remain suspended in air for a longer time. Therefore, in still air, the horizontal distance that a healthy individual should maintain from an infected one is based on the bigger droplets, but the time interval to be maintained is based on the smaller droplets. We show that in places with wind flow, the lighter droplets travel a larger distance and remain suspended in air for a longer time. Therefore, we conclude that both temporal and geometric distance that a healthy individual should maintain from an infected one is based on the smaller droplets under flowing air, which makes the use of a mask mandatory to prevent the virus. Maintenance of only stationary separation between healthy and infected individuals is not substantiated. The quantitative results obtained here will be useful to devise strategies for preventing the spread of other types of droplets containing microorganisms.

Clinical outcomes and quality of life associated with the use of a biosynthetic mesh for complex ventral hernia repair: analysis of the "Italian Hernia Club" registry.

With the development of newer meshes and approaches to hernia repair, it is currently difficult to evaluate their performances while considering the patients' perspective. The aim of the study was to assess the clinical outcomes and quality of life consequences of abdominal hernia repairs performed in Italy using Phasix and Phasix ST meshes through the analysis of real-world data to support the choice of new generation biosynthetic meshes. An observational, prospective, multicentre study was conducted in 10 Italian clinical centres from May 2015 to February 2018 and in 15 Italian clinical centres from March 2018 to May 2019. The evaluation focused on patients with VHWG grade II-III who underwent primary ventral hernia repair or incisional hernia intervention with a follow-up of at least 18 months. Primary endpoints included complications' rates, and secondary outcomes focused on patient quality of life as measured by the EuroQol questionnaire. Seventy-five patients were analysed. The main complications were: 1.3% infected mesh removal, 4.0% superficial infection requiring procedural intervention, 0% deep/organ infection, 8.0% recurrence, 5.3% reintervention, and 6.7% drained seroma. The mean quality of life utility values ranged from 0.768 (baseline) to 0.967 (36 months). To date, Phasix meshes have proven to be suitable prostheses in preventing recurrence, with promising outcomes in terms of early and late complications and in improving patient quality of life.

Dermoscopic patterns of intradermal naevi.

BACKGROUND: Intradermal naevi represent a benign histopathological variant of common melanocytic naevi. Studies describing dermoscopic criteria of dermal naevi are very limited. OBJECTIVES: To identify dermoscopic features of dermal naevi in order to facilitate differential diagnosis from malignant lesions. METHODS: A 15-year retrospective study was performed to evaluate the dermoscopic characteristics of 202 dermal naevi, histopathologically diagnosed through the analysis of digital dermoscopic images performed with polarised light dermoscopy. For each lesion, vascular pattern, pigment pattern and other dermoscopic clues were evaluated. RESULTS: 147 Unna naevi and 55 Miescher naevi were included in the study. Brown pigment (37.1%) was the pigment pattern most frequently observed in both Unna and Miescher naevi, followed by cobblestone pattern (30.6%) in Unna naevi and white areas (23.6%) and dotted/globule pattern (20%) in Miescher naevi. As regards the vascular patterns, the polymorphic one was the most frequently observed (34.6%). The combination between comma-shaped and arborising vessels was the most common among all naevi. CONCLUSIONS: Our study describes the dermoscopic features of dermal naevi that may help to differentiate them from malignant lesions such as basal cell carcinoma, amelanotic melanoma and Spitz naevi.

Cutaneous melanoma associated with naevi prevalence: A 15-year cross-sectional retrospective study.

BACKGROUND/OBJECTIVES: Melanoma may develop de novo or naevus associated (NAM). The exact prevalence and features of NAM are not fully elucidated. METHODS: A 15-year cross-sectional retrospective study was performed of all melanoma cases diagnosed and treated at the skin cancer centre of the University of Naples Federico II from September 2003 to August 2018. Data collected included patient's age, gender, melanoma anatomic site, Breslow thickness, and histolopathology including melanoma-associated lesion characteristics. RESULTS: A total of 1986 melanomas were included in the study. Based on histolopathogical examination, NAM represented 8.4% (n = 167) with de novo melanoma representing the great majority of the melanomas (91.6%). NAM was significantly more common in younger age compared to de novo melamoma (mean age 48 ± 14.9 vs 54.3 ± 15.9 years, P < 0.001), and more frequently involved the trunk (62.3% vs 51.8% P = 0.01). Mean Breslow thickness was significantly higher in de novo melanoma  compared to NAM (0.97 ± 1.48 mm vs 0.83 ± 0.95, P < 0.001). However, in situ melanoma was more commonly observed in de novo melanoma (n = 640, 35.2%) rather than NAM (n = 41, 24.5%; P < 0.01) whereas invasive melanoma represented 75.5% (n = 126) of NAM and 64.8% (n = 1179) of de novo melanoma, P < 0.01. CONCLUSIONS: NAM represent a small percentage of melanomas (8.4%) compared to de novo melanoma. NAM appeared to be significantly more common in younger age and more frequently involved the trunk, being associated with an overall better prognosis, due to a lower mean Breslow thickness respect to de novo melanoma.

How to Increase Adherence and Compliance in Acne Treatment? A Combined Strategy of SMS and Visual Instruction Leaflet.

INTRODUCTION: Acne is a common skin disease with important psychosocial impact. Often inadequate compliance affects the efficacy of the therapy. Because of emerging use of mobile and electronic health technology, the recent literature evaluated the helpfulness of the tools in medication adherence. The first goal of our study was to evaluate the adherence to therapy with topical adapalene 0.3%/benzoyl peroxide (A-BPO) 2.5% in different groups of patients who received explicative information supported by different strategies. The second goal was to evaluate the patient's quality of life and skin parameters. MATERIALS AND METHODS: We enrolled 126 subjects with mild to severe acne vulgaris. They were randomized into 3 groups of 42 patients each and applied daily topical A-BPO (0.3%, 2.5%) for 12 weeks. The first group (G1) was trained on the gel application by an explicative leaflet. The second group (G2) received the same instructions as group 1 and a daily SMS to remind them of the application of the product. The third group (G3) only received standard instructions. Evaluations were performed at the beginning of treatment (T0) and after 12 weeks (T1): assessment of acne severity using the Investigator's Global Assessment (IGA) Scale for Acne Severity, quality of life by the Cardiff Acne Disability Index (CADI) and the Patient-Doctor Relationship Depth-of-Relationship Scale (PDRDS), skin pH, grade of hydration and adherence to treatment with a 7-day recall calendar were also measured. RESULTS: After 12 weeks of therapy, we observed a reduction in IGA in all groups confirming the clinical efficacy of the product. In the multiple comparison analysis of IGA score reduction, a significant difference was found in G2 versus G1 and G2 versus G3, while the G1 versus G3 comparison was not statistically significant. However, the leaflet group (G1) showed better results compared to the no-leaflet group (G3). Supporting these data, we observed that adherence days correlated positively with the improvement of the single parameters. Moreover, we observed that SMS and leaflet groups had a greater improvement in quality of life evaluated by CADI and PDRDS scores. CONCLUSIONS: According to our data, this experimental setup based on text message service and leaflet service is inexpensive and easy to use. Physicians could consider using these items in their practice to enhance patient adherence and satisfaction as well as treatment outcome.