Coalescence of surface bubbles: The crucial role of motion-induced dynamic adsorption layer.

The formation of motion-induced dynamic adsorption layers of surfactants at the surface of rising bubbles is a widely accepted phenomenon. Although their existence and formation kinetics have been theoretically postulated and confirmed in many experimental reports, the investigations primarily remain qualitative in nature. In this paper we present results that, to the best of our knowledge, provide a first quantitative proof of the influence of the dynamic adsorption layer on drainage dynamics of a single foam film formed under dynamic conditions. This is achieved by measuring the drainage dynamics of single foam films, formed by air bubbles of millimetric size colliding against the interface between n-octanol solutions and air. This was repeated for a total of five different surfactant concentrations and two different liquid column heights. All three steps preceding foam film rupture, namely the rising, bouncing and drainage steps, were sequentially examined. In particular, the morphology of the single film formed during the drainage step was analyzed considering the rising and bouncing history of the bubble. It was found that, depending on the motion-induced state of adsorption layer at the bubble surface during the rising and the bouncing steps, single foam film drainage dynamics can be spectacularly different. Using Direct Numerical Simulations (DNS), it was revealed that surfactant redistribution can occur at the bubble surface as a result of the bouncing dynamics (approach-bounce cycles), strongly affecting the interfacial mobility, and leading to slower rates of foam film drainage. Since the bouncing amplitude directly depends on the rising velocity, which correlates in turn with the adsorption layer of surfactants at the bubble surface during the rising step, it is demonstrated that the lifetime of surface bubbles should intimately be related to the history of their formation.

Silver Is Not Equal to Silver: Synthesis and Evaluation of Silver Nanoparticles with Low Biological Activity, and Their Incorporation into C12Alanine-Based Hydrogel.

A new type of silver nanoparticles (AgNPs) was prepared and comprehensively studied. Scanning electron microscopy (SEM) and dynamic light scattering (DLS) analyses indicated that 24 nm AgNPs with narrow size distribution were obtained while Z-potential confirms their good stability. The composites of the obtained AgNPs with nontoxic-nature-inspired hydrogel were formed upon cooling of the aqueous solution AgNPs and C12Ala. The thermal gravimetric analysis (TGA) and the differential scanning calorimetry (DSC) do not show significant shifts in the characteristic temperature peaks for pure and silver-enriched gels, which indicates that AgNPs do not strongly interact with C12Ala fibers, which was also confirmed by SEM. Both AgNPs alone and in the assembly with the gelator C12Ala were almost biologically passive against bacteria, fungus, cancer, and nontumor human cells, as well as zebra-fish embryos. These studies proved that the new inactive AgNPs-doped hydrogels have potential for the application in therapy as drug delivery media.

Synthesis and Characterization of Size- and Charge-Tunable Silver Nanoparticles for Selective Anticancer and Antibacterial Treatment.

Advances in the research of nanoparticles (NPs) with controlled charge and size are driven by their potential application in the development of novel technologies and innovative therapeutics. This work reports the synthesis, characterization, and comprehensive biological evaluation of AgNPs functionalized by N,N,N-trimethyl-(11-mercaptoundecyl) ammonium chloride (TMA) and trisodium citrate (TSC). The prepared AgNPs were well characterized in terms of their morphological, spectroscopic and functional properties and biological activities. The implementation of several complementary techniques allowed not only the estimation of the average particle size (from 3 to 40 nm depending on the synthesis procedure used) but also the confirmation of the crystalline nature of the NPs and their round shape. To prove the usefulness of these materials in biological systems, cellular uptake and cytotoxicity in microbial and mammalian cells were determined. Positively charged 10 nm Ag@TMA2 revealed antimicrobial activity against Gram-negative bacteria with a minimum inhibitory concentration (MIC) value of 0.17 µg/mL and complete eradication of Escherichia coli (7 logs) for Ag@TMA2 at a concentration of 0.50 µg/mL, whereas negatively charged 10 nm Ag@TSC1 was effective against Gram-positive bacteria (MIC = 0.05 µg/mL), leading to inactivation of Staphylococcus aureus at relatively low concentrations. In addition, the largest 40 nm Ag@TSC2 was shown to exhibit pronounced anticancer activity against murine colon carcinoma (CT26) and murine mammary gland carcinoma (4T1) cells cultured as 2D and 3D tumor models and reduced toxicity against human HaCaT keratinocytes. Among the possible mechanisms of AgNPs are their ability to generate reactive oxygen species, which was further evaluated in vitro and correlates well with cellular accumulation and overall activity of AgNPs. Furthermore, we confirmed the anticancer efficacy of the most potent Ag@TSC2 in hiPSC-derived colonic organoids and demonstrated that the NPs are biocompatible and applicable in vivo. A pilot study in BALB/c mice evidenced that the treatment with Ag@TSC2 resulted in temporary (>60 days) remission of CT26 tumors.

Tips for Effective Implementation of Virtual Reality Exposure Therapy in Phobias-A Systematic Review.

Background: The high incidence of phobias and the limited accessibility of psychotherapy are the reasons for the search for alternative treatments that increase the availability of effective treatment. The use of virtual reality (VR) technology is an option with the potential to overcome the barriers in obtaining an effective treatment. VR exposure therapy (VRET) is based on a very similar rationale for in vivo exposure therapy. The study aimed to answer the question of how to perform exposure therapy in a virtual reality environment so that it is effective. Methods: A systematic review of the literature, using PRISMA guidelines, was performed. After analysis of 362 records, 11 research papers on agoraphobia, 28 papers on social phobia and 10 about specific phobias were selected for this review. Results: VRET in agoraphobia and social phobia is effective when performed from 8 to 12 sessions, on average once a week for at least 15 min. In turn, the treatment of specific phobias is effective even in the form of one longer session, lasting 45-180 min. Head mounted displays are an effective technology for VRET. Increasing the frequency of sessions and adding drug therapy may shorten the overall treatment duration. The effectiveness of VRET in phobias is greater without concomitant psychiatric comorbidity and on the condition of inducing and maintaining in the patient an experience of immersion in the VR environment. Long-term studies show a sustained effect of VRET in the treatment of phobias. Conclusion: A large number of studies on in VR exposure therapy in phobias allows for the formulation of some recommendations on how to perform VRET, enabling the effective treatment. The review also indicates the directions of further VRET research in the treatment of phobias.

The Effect of Smartphone-Based Cognitive Training on the Functional/Cognitive Markers of Schizophrenia: A One-Year Randomized Study.

BACKGROUND: Cognitive impairment is associated with long-term disability that results in the deterioration of both the social and professional status of individuals with schizophrenia. The impact of antipsychotic therapy on cognitive function is insufficient. Cognitive training is therefore proposed as a tool for cognitive rehabilitation in schizophrenia. In this study we investigated the effect of self-administered cognitive training using a smartphone-based application on the cognitive function of paranoid schizophrenia patients focusing on response time, correct answer rate, incorrect answer rate, and fatigability to check, if these functions can be functional markers of successful cognitive-smartphone rehabilitation. METHODS: 1-year multicenter, open-label randomized study was conducted on 290 patients in a state of symptomatic remission. 191 patients were equipped with the full version of the application and conducted cognitive training twice a week. Reference group (n = 99) was provided with a version of the application having only limited functionality, testing the cognitive performance of patients every 6 months. RESULTS: Statistically significant improvement was observed in both the rate of correct answers (by 4.8%, p = 0.0001), and cognitive fatigability (by 2.9%, p = 0.0001) in the study group, along with a slight improvement in the rate of incorrect answers (by 0.9%, p = 0.15). In contrast, the reference group, who performed cognitive training every 6 months, demonstrated no significant changes in any cognitive activities. CONCLUSIONS: Cognitive trainings facilitated by a smartphone-based application, performed regularly for a longer period of time are feasible and may have the potential to improve the cognitive functioning of individuals with schizophrenia. Correct answers and cognitive fatigability have potential to be functional markers of successful smartphone-based psychiatric rehabilitations in schizophrenia patients.

A telemedicine platform to improve clinical parameters in paranoid schizophrenia patients: Results of a one-year randomized study.

OBJECTIVE: The study objective was to test a smartphone-based MONEO platform designed to improve the clinical condition of paranoid schizophrenia patients. Telemedicine treatment is considered to be as effective as traditional treatment in outpatient clinics. METHOD: A total of 290 patients with paranoid schizophrenia in the symptomatic remission state were recruited to this 12-month multicenter, open-label randomized trial. A study group (n = 191) received a smartphone with the MONEO platform installed. Patients conducted cognitive training twice a week. Patients' mental state was assessed every month via teleconference. A placebo group (n = 99) received a platform with functionality limited to monthly teleconsultation and performing cognitive training every 6 months. The clinical status was measured using the Positive and Negative Syndrome Scale (PANSS), Calgary, and Clinical Global Impression-Severity (CGI-S) clinical scales. RESULTS: After 12 months, a significant reduction of symptoms was observed in the study group, as assessed using the Calgary (36%, P < 0.01) and PANSS (8.6%, P < 0.05) scales. Symptom reduction of 23.6% was also observed in the placebo group (P < 0.05, Calgary scale). In the study group, depression, positive symptoms, excitement, general psychopathology and disorganization subscales decreased significantly, while in the placebo group, only the depression subscale decreased. The greatest improvement of 11.2% (study group, P < 0.05), vs 16.2% (placebo group, P < 0.05), was observed for the depression subscale. CONCLUSION: The MONEO platform was demonstrated to positively influence the clinical condition of individuals with paranoid schizophrenia. A lack of negative consequences associated with usage of the device was also reported.

Clinical characteristics and thromboembolic risk of atrial fibrillation patients with and without congestive heart failure. Results from the CRATF study.

Congestive heart failure (CHF) and atrial fibrillation (AF) frequently coexist and are associated with increased risk of cardiovascular events.To compare baseline characteristics, comorbidities and pharmacotherapy in AF patients with concomitant CHF to those without CHF.The study included 3506 real-life AF patients with (37.1%) and without CHF - participants of the multicentre, retrospective MultiCenter expeRience in AFib patients Treated with OAC (CRAFT) trial (NCT02987062).All patients were treated with non-vitamin K antagonist oral anticoagulants (NOAC) or vitamin K antagonists (VKA). The frequency of NOAC among patients with and without CHF was 45.6% and 43.2%, respectively (P = .17). Patients with CHF were older (73.3 vs 64.7 years, P <.001), less likely to be women (37.4% vs 42%, P = .007), had higher CHA2DS2-VASc score (3.8 ±â€Š1.7 vs 2.6 ±â€Š1.8, P <.001), more often had permanent AF (53.0% vs 13.4%, P <.001), chronic obstructive pulmonary disease (16.7% vs 4.9%, P <.001), coronary artery disease (64.3% vs 29.8%, P <.001), peripheral vascular disease (65.3% vs 31.4%, P <.001), chronic kidney disease (43.1% vs 10.0%, P <.001), liver fibrosis (5.7% vs 2.6%, P <.001), neoplasm (9.6% vs 7.3%, P = .05), history of composite of stroke, transient ischemic attack or systemic embolization (16.2% vs 10.7%, P <.001), pacemaker (27.4% vs 22.1%, P = .004), implantable cardioverter-defibrillator (22.7% vs 0.8%, P <.001) or transaortic valve implantation (4.0% vs 0.8%, P <.001), cardiac resynchronization therapy (8.7% vs 0.3%, P <.001), composite of kidney transplantation, hemodialysis or creatinine level > 2.26 mg/dL (3.6% vs 0.8%, P <.001) and had less often hypertension (69.4% vs 72.5%, P = .05).Patients with AF and CHF had a higher thromboembolic risk and had more concomitant diseases.

Study design and rationale for biomedical shirt-based electrocardiography monitoring in relevant clinical situations: ECG-shirt study.

BACKGROUND: Today, the main challenge for researchers is to develop new technologies which may help to improve the diagnoses of cardiovascular disease (CVD), thereby reducing healthcare costs and improving the quality of life for patients. This study aims to show the utility of biomedical shirt-based electrocardiography (ECG) monitoring of patients with CVD in different clinical situations using the Nuubo® ECG (nECG) system. METHODS: An investigator-initiated, multicenter, prospective observational study was carried out in a cardiology (adult and pediatric) and cardiac rehabilitation wards. ECG monitoring was used with the biomedical shirt in the following four independent groups of patients: 1) 30 patients after pulmonary vein isolation (PVI), 2) 30 cardiac resynchronization therapy (CRT) recipients, 3) 120 patients during cardiac rehabilitation after myocardial infarction, and 4) 40 pediatric patients with supraventricular tachycardia (SVT) before electrophysiology study. Approval for all study groups was obtained from the institutional review board. The biomedical shirt captures the electrocardiographic signal via textile electrodes integrated into a garment. The software allows the visualization and analysis of data such as ECG, heart rate, arrhythmia detecting algorithm and relative position of the body is captured by an electronic device. DISCUSSION: The major advantages of the nECG system are continuous ECG monitoring during daily activities, high quality of ECG recordings, as well as assurance of a proper adherence due to adequate comfort while wearing the shirt. There are only a few studies that have examined wearable systems, especially in pediatric populations. TRIAL REGISTRATION: This study is registered in ClinicalTrials.gov: Identifier NCT03068169. (Cardiol J 2018; 25, 1: 52-59).