Through-Drop Imaging of Liquid-Solid Interfaces: From Contact Angle Variations Along the Droplet Perimeter to Mapping of Contact Angles Across a Surface.

When a droplet interacts with a water-repellent surface, its triple-phase contact line typically exhibits varying contact angles, which can vary from point-to-point across the surface. Consequently, measuring the contact angles along the contact line would provide a better representation of the wetting properties of the surface than a single average contact angle. However, an effective method for estimating the local contact angle along the contact line on opaque hydrophobic surfaces is currently lacking. Here we present a method that combines through-drop imaging of the wetting interface during a sliding experiment with Finite Element Modeling of the droplet to estimate contact angle values along the contact line. Using this method, the mean advancing and receding contact angles were measured on four types of hydrophobic samples with contact angles between 99 and 178.9°. The method was further used to produce detailed advancing and receding contact angle maps of surfaces with wetting patterns with an unprecedented resolution of 3 µm.

Monitoramento de vetores do gênero Aedes durante o inverno no município de Barbacena, Minas Gerais, Brasil ­ 2018 / Monitoring of vectors of the genus Aedes during winter in the municipality of Barbacena, Minas Gerais, Brazil ‒ 2018

Objetivo: estimar a oviposição e distribuição espacial de vetores Aedes durante a estação de inverno e correlacionar essas estimativas com dados climáticos do mesmo período. Métodos: estudo de campo conduzido no município de Barbacena-MG, em 2018. O monitoramento, a coleta de ovos e a estimativa de índices estegômicos de vetores Aedes foram obtidos por meio de ovitrampas. Os Índices de Densidade de Ovos (IDO) e de Positividade de Ovitrampas (IPO%) foram estimados conforme estações climáticas e semanas epidemiológicas. A correlação entre parâmetros meteorológicos (temperatura/pluviometria) e índices estegômicos (IDO/IPO) foi determinada pelo coeficiente de Spearman. Resultados: um total de 1.080 ovitrampas, instaladas em 39 bairros, foi analisado durante 10 semanas epidemiológicas, fornecendo um total de 970 ovos. Nas estações de outono, inverno e primavera, foram obtidos, respectivamente, 421, 470 e 70 ovos. Durante o outono, houve variação do IDO entre 14,2 e 34,2. O IPO manteve-se constante em 4,5%. Durante o inverno, houve variação do IDO entre 0,00 e 47,50 e do IPO entre 0,00% e 8,25%. Houve correlação negativa significativa tanto entre aumento da precipitação mensal e diminuição do número de ovos coletados (rho=-0.673) quanto entre aumento da precipitação mensal e diminuição do IPO (rho=-0.612). O valor geral do IDO e do IPO nas 10 semanas foi, respectivamente, 22,04 e 4,17% e, na estação de inverno, foi, respectivamente, 23,50 e 3,73%. Conclusão: os achados corroboram a presença de ovos e vetores do gênero Aedes mesmo em condições climáticas adversas para essas espécies e sustentam ações de manejo sanitário durante todo o ano.

Objective: to estimate oviposition and spatial distribution of Aedes vectors during the winter season and correlate these estimates with climate data from the same period. Methods: field study conducted in the municipality of Barbacena-MG in 2018. Monitoring, egg collection, and estimation of stegomic indices of Aedes were obtained using ovitraps. The Indices of Egg Density (EDI) and Positive Ovitrap (POI%) were estimated according to climatic seasons and epidemiological weeks. The correlation between meteorological parameters (temperature/rainfall) and stegomic indices (EDI/POI) was determined by the Spearman coefficient. Results: a total of 1,080 ovitraps installed in 39 neighborhoods were analyzed during ten (10) epidemiological weeks, providing a total of 970 eggs. In the autumn, winter, and spring seasons, 421, 470, and 70 eggs were obtained, respectively. During the autumn, there was a variation in EDI between 14.2­34.2. The POI remained constant at 4.5%. During the winter, the EDI varied between 0.00­47.50, and the POI varied between 0.00%­8.25%. There was a significant negative correlation, respectively, between an increase in monthly precipitation and a decrease in the number of eggs collected (rho=-0.673) and between an increase in monthly precipitation and a decrease in POI (rho=-0.612). The overall value of EDI and POI in the ten (10) weeks was 22.04 and 4.17%, and in the winter season, they were 23.50 and 3.73%, respectively. Conclusion: the findings corroborate the presence of eggs and vectors of the genus Aedes even in adverse climatic conditions for these species and support health management actions throughout the year.

Through-drop imaging of moving contact lines and contact areas on opaque water-repellent surfaces.

A myriad of natural surfaces such as plant leaves and insect wings can repel water and remain unwetted inspiring scientists and engineers to develop water-repellent surfaces for various applications. Those natural and artificial water-repellent surfaces are typically opaque, containing micro- and nano-roughness, and their wetting properties are determined by the details at the actual liquid-solid interface. However, a generally applicable way to directly observe moving contact lines on opaque water-repellent surfaces is missing. Here, we show that the advancing and receding contact lines and corresponding contact area on micro- and nano-rough water-repellent surfaces can be readily and reproducibly quantified using a transparent droplet probe. Combined with a conventional optical microscope, we quantify the progression of the apparent contact area and apparent contact line irregularity in different types of superhydrophobic silicon nanograss surfaces. Contact angles near 180° can be determined with an uncertainty as low as 0.2°, that a conventional contact angle goniometer cannot distinguish. We also identify the pinning/depinning sequences of a pillared model surface with excellent repeatability and quantify the progression of the apparent contact interface and contact angle of natural plant leaves with irregular surface topography.

Maximizing lymph node dissection from fresh lung cancer specimens.

Evaluation of lymph nodes during lung cancer resection is essential for pathologic staging and adjuvant treatment decisions. We developed a standardized approach for grossing resected lobes and segments to better assign the N1 category to hilar and peripheral lymph nodes. Lung specimens were dissected centrifugally from the bronchial stump, and all lymph nodes at the segmental and subsegmental bifurcations were removed. When combined with mediastinal lymph node dissection, this approach will likely maximize the number of lymph nodes analysed and improve the accuracy of pathologic N descriptor classification.

Impact of Cashew (Anacardium occidentale L.) by-Product on Composition and Metabolic Activity of Human Colonic Microbiota In Vitro Indicates Prebiotic Properties.

Cashew apple by-product (CAB) is an important agro-industrial waste still underutilized, although it has been characterized as source of a variety of nutrients and bioactive compounds. This study evaluated the capability of freeze-dried CAB (FCAB) submitted to a simulated gastrointestinal digestion of inducing changes in relative abundance of distinct microbial groups found as part of human colonic microbiota, as well as in pH and short-chain fatty acid production during a 24-h in vitro fermentation using a pooled human fecal inocula. FCAB increased the relative abundance of Bifidobacterium and Lactobacillus/Enterococcus during colonic fermentation, besides to decrease the relative abundance of Bacteroides/Prevotella, Eubacterium rectale/Clostridium coccoides, and Clostridium histolyticum. FCAB increased the counts of lactic acid bacteria and decreased the counts of Enterobacteriaceae during colonic fermentation. Furthermore, FCAB decreased pH and increased the production of short-chain fatty acids in colonic fermentation media. These effects could be linked to contents of dietary fibers and the presence of fructans and different phenolic compounds found in FCAB. These results showed that FCAB induced positive alterations in composition and metabolic activity of human colonic microbiota in vitro, which indicate prebiotic properties.

The learning curve on uniportal video-assisted thoracic surgery: An analysis of proficiency.

OBJECTIVES: Minimally invasive techniques for lung cancer surgery have revolutionized thoracic surgery, and single-port approaches are becoming increasingly used. We analyzed our experience with uniportal video-assisted thoracoscopic surgery for lobectomy to identify the number of procedures necessary to achieve proficiency according to clinical outcomes. METHODS: We queried our institutional prospective database for all single-port lobectomies in patients with early-stage lung cancer performed by a single surgeon from 2014 to 2017; 274 patients met the inclusion criteria. Using cubic splines, we derived 3 distinct learning phases based on the length of the procedure. Blood loss, additional port insertion, and conversion to thoracotomy were also compared according to these learning phases. RESULTS: The initial phase (procedures 1-60) had the longest procedure times and the most variability in procedure length (158.8 ± 52.2 minutes) compared with the transition phase (procedures 61-140; 145.9 ± 43.8 minutes) and the proficient phase (procedures 141-274; 117.9 ± 32.6 minutes, P < .001). Blood loss (156 mL vs 130.4 mL vs 64.9 mL, P = .003), conversion rate to thoracotomy (11.7% vs 3.8% vs 0.7%, P = .001), and need for a second incision (8.3% vs 5% vs 0.7%, P = .025) were all highest during the initial phase. In a multivariable model, there was a significant interaction between procedure number and learning phase (P = .003), indicating that the effect of each additional procedure on procedure length differed in each phase. CONCLUSIONS: In this analysis, a distinct learning curve for uniportal video-assisted thoracoscopic surgery lobectomy was observed. Procedure time decreased sharply at approximately the 60th procedure, but 80 additional lobectomies were required to master the approach.

Outcomes of Uniportal vs Multiportal Video-Assisted Thoracoscopic Lobectomy.

The optimal number of incisions for video-assisted thoracoscopic surgery (VATS) lobectomy, the standard treatment for early-stage nonsmall cell lung cancer (NSCLC), is still a matter of great debate. To compare single-incision (uniportal) VATS (U-VATS) with traditional multiportal VATS (M-VATS), we retrospectively reviewed the surgical outcomes of a large cohort of patients. Our prospectively maintained institutional database was queried retrospectively. All patients from 2014 to 2017 who underwent VATS lobectomy as the primary procedure for clinical stage I or II NSCLC were identified. A univariate comparison and a propensity-matched analysis incorporating preoperative variables were performed. The incidence of postoperative complications was compared. During the study period, 722 patients underwent VATS lobectomy for early-stage NSCLC, 62% by M-VATS, and 38% by U-VATS. In the univariate analysis, U-VATS performed by an experienced surgeon was associated with decreased intraoperative bleeding and shortened duration of surgery, duration of chest tube drainage, and length of hospital stay as compared with M-VATS (P < 0.001). Mediastinal lymph node dissection and complete resection were accomplished similarly using U-VATS and M-VATS. When the 2 approaches were compared through propensity matching, U-VATS was associated with fewer pneumonias (P = 0.012), as well as decreased intraoperative bleeding (P < 0.001), faster surgery (P < 0.001), shorter duration of chest tube drainage (P = 0.001), and shorter hospital stay (P < 0.001). At our institution, in the hands of an experienced surgeon, U-VATS lobectomy is safe, feasible, and can result in similar short-term outcomes for early-stage NSCLC as compared with M-VATS.

Computed tomography-guided platinum microcoil lung surgery: A cross-sectional study.

OBJECTIVE: The study objective was to provide a 5-year update on our tertiary-level institutional experience with computed tomography-guided platinum microcoil lung surgery. METHODS: A retrospective cross-sectional study was conducted. All patients admitted to the Thoracic Service at Vancouver General Hospital to undergo computed tomography-guided microcoil lung surgery were included. Key primary outcome variables were successful nodule localization and severity of adverse events associated with placement. Secondary outcomes included nodule characteristics on preoperative computed tomography chest and nodule surgical pathology. Continuous variables were reported as mean (± standard deviation), and counts were reported as proportions n (%). RESULTS: A total of 97 lung nodules were resected in 92 patients. Mean age was 65.3 (±10.6) years, and 59 (61%) were female. All 97 nodules (100%) were successfully localized using video-assisted thoracic surgery wedge resection. There were 59 cases (60.8%) of placement-related events noted on computed tomography of the chest. All were minor and self-limited in nature and did not require treatment: pneumothorax 45 (46.4%), lung hematoma 18 (18.6%), dislodgement 4 (4.1%), and hemoptysis 2 (2.1%). Mean nodule diameter was 13.2 mm (±6.7). Density was nonsolid in 27 (27.8%) and semi-solid in 27 (27.8%). There was a single case of positive surgical margin, and 4 (4.1%) went on to completion lobectomy. Non-small lung cancer was identified in 66 nodules. CONCLUSIONS: Computed tomography-guided platinum microcoil lung surgery is safe with a favorable clinical adverse event profile and is suitable for poor-risk patients. The method is efficient, yielding 100% diagnostic localization in our 5-year update. It eliminates the need for thoracotomy and palpation to localize worrisome subpleural tiny nodules. It is ideal for the management of changing nodules concerning for early lung cancer and diagnosis of small indeterminate lung nodules or metastases.

PET-CT has low specificity for mediastinal staging of non-small-cell lung cancer in an endemic area for tuberculosis: a diagnostic test study (LACOG 0114).

BACKGROUND: The present study aims to assess the performance of 18F-FDG PET-CT on mediastinal staging of non-small cell lung cancer (NSCLC) in a location with endemic granulomatous infectious disease. METHODS: Diagnostic test study including patients aged 18 years or older with operable stage I-III NSCLC and indication for a mediastinal lymph node biopsy. All patients underwent a 18F-FDG PET-scan before invasive mediastinal staging, either through mediastinoscopy or thoracotomy, which was considered the gold-standard. Surgeons and pathologists were blinded for scan results. Primary endpoint was to evaluate sensitivity, specificity and positive and negative predictive values of PET-CT with images acquired in the 1st hour of the exam protocol, using predefined cutoffs of maximal SUV, on per-patient basis. RESULTS: Overall, 85 patients with operable NSCLC underwent PET-CT scan followed by invasive mediastinal staging. Mean age was 65 years, 49 patients were male and 68 were white. One patient presented with active tuberculosis and none had HIV infection. Using any SUV_max > 0 as qualitative criteria for positivity, sensitivity and specificity were 0.87 and 0.45, respectively. Nevertheless, even when the highest SUV cut-off was used (SUV_max ≥5), specificity remained low (0.79), with an estimated positive predictive value of 54%. CONCLUSIONS: Our findings are in line with the most recent publications and guidelines, which recommend that PET-CT must not be solely used as a tool to mediastinal staging, even in a region with high burden of tuberculosis. TRIAL REGISTRATION: The LACOG 0114 study was registered at ClinicalTrials.gov , before study initiation, under identifier NCT02664792.

Post esophagectomy diaphragmatic hernia: a case report of a rare cause of acute respiratory distress.

BACKGROUND: Diaphragmatic hernia is frequent among the elderly and is usually associated with mild chronic digestive and respiratory symptoms. CASE PRESENTATION: An elderly post-esophagectomy male patient, in the early postoperative period of cardiac surgery, presented with acute respiratory distress. An emergent surgery was performed to reduce a giant diaphragmatic herniation. CONCLUSIONS: An acute transhiatal herniation can cause serious respiratory impairment; surgical repair should be considered in select patients of cardiac surgery.

Direct measurement of the capillary condensation time of a water nanobridge.

Water menisci wet all sorts of cavities, produce among the most intense forces at the nanoscale and play a role in many physical and chemical processes. The physical properties of these menisci are therefore relevant to understand a multitude of phenomena at the nanoscale where these are involved. Here, using a force feedback microscope, we directly measured the capillary condensation time of a water meniscus, by approaching two surfaces at different speeds and monitoring the relative position of the surfaces at the instant the meniscus is formed.

Extended uniportal video-assisted thoracic surgery for lung cancer: is it feasible?

Since the first description of uniportal video-assisted thoracic surgery (U-VATS) (or single-port) lobectomy, several centers in Asia and Europe rapidly adopted this technique as a standard approach for treatment of early stage non-small cell lung cancer (NSCLC). Despite the controversies regarding feasibility and completeness of resection, thoracic surgeons in high volume centers keep pushing the limits to perform very complex procedures also known as "extended resections" through minimally invasive surgery. Published series and case reports confirm the viability of U-VATS in highly complex surgical cases such as pneumonectomy, chest wall resection and bronchoplasty, which require experience and technical ability to be performed through a 3-6 cm single incision. In this article, the authors would like to present several clinical indications of locally advanced NSCLC and the technical aspects to accomplish an extended resection through U-VATS.

The technique of VATS right pneumonectomy.

Pneumonectomy has higher morbidity and mortality rate than any other anatomic lung resection. It is infrequently performed by VATS and mostly in high volume centers. The handling of central vessels with long instruments across very small incisions instead of palpation is the main cause of surgeon's discomfort and resistance to perform this radical type of resection. Published data on VATS pneumonectomy is still limited and based on case series. Nevertheless, the available series suggest that VATS pneumonectomy is at least equivalent to open pneumonectomy. Through a case presentation illustrated with surgical videos, we aim to describe the main technical features of a uniportal VATS right pneumonectomy for lung cancer. The clinical indications, contraindications, patient's preoperative evaluation and postoperative care will also be discussed.

Anatomic bisegmentectomy for synchronous lung adenocarcinoma.

Modern thoracic surgery requires the ability to manage patients with ground glass opacities (GGO). However, due to the lack of a standardize approach in our institution these cases are discussed in the tumor board. We here present our therapeutic rationale in a case of a patient with multiple GGOs, who underwent an en-bloc anatomic bisegmentectomy as surgical treatment for a synchronous lung adenocarcinoma.

Effect of sliding friction in harmonic oscillators.

Sliding friction is ubiquitous in nature as are harmonic oscillators. However, when treating harmonic oscillators the effect of sliding friction is often neglected. Here, we propose a simple analytical model to include both viscous and sliding friction in common harmonic oscillator equations, allowing to separate these different types of dissipation. To compare this model with experimental data, a nanometric vibration was imposed on a quartz tuning fork, while an atomic force microscope tip was used to disturb its motion. We analyzed tuning fork resonance and 'ring down' experimental curves and for each case calculated the amount of sliding friction and of viscous damping, finding an agreement between the two different experiments and the model proposed.

Uniportal middle lobectomy after a previous right upper lobectomy.

Video-assisted thoracoscopic surgery (VATS) using a 3.5 cm single incision (uniportal) may not only result in better pain control, earlier mobilization and shorter hospital stays, but can also provide safer and clear visualization to perform thoracoscopic dissection during complex surgeries. This is a case of a 55-year-old woman who underwent redo-thoracoscopy through uniportal approach for a middle-lobe lobectomy, after a previous right-upper lobectomy.