Production of Poly(vinylalcohol) Nanoyarns Using a Special Saw-like Collector

This work introduces an electrospinning method for laboratory-scale production of nanofibrous materials from polyvinylalcohol (PVA) nanofibres. A procedure for the subsequent production of twisted yarns from the aligned nanofibrous strand is introduced as well. Both needle and needleless electrospinning variants were employed Mechanical properties of the nanoyarns produced were tested using a VIBRODYN 400 and their morphology was investigated by light and electron microscopy. The work also introduces a simple analysis of the field strength that causes the prevailing unidirectional fiber deposition between neighbouring lamellae of a special saw-like collector The field strength analysis was carried out both analytically and by modelling based on the software COMSOL Multiphysics.MSMT project CARSILA [ME10145]; [GACR: P208/12/0105

Drivers of population structure of the bottlenose dolphin (Tursiops truncatus) in the Eastern Mediterranean Sea

The drivers of population differentiation in oceanic high dispersal organisms, have been crucial for research in evolutionary biology. Adaptation to different environments is commonly invoked as a driver of differentiation in the oceans, in alternative to geographic isolation. In this study, we investigate the population structure and phylogeography of the bottlenose dolphin (Tursiops truncatus) in the Mediterranean Sea, using microsatellite loci and the entire mtDNA control region. By further comparing the Mediterranean populations with the well described Atlantic populations, we addressed the following hypotheses: (1) bottlenose dolphins show population structure within the environmentally complex Eastern Mediterranean Sea; (2) population structure was gained locally or otherwise results from chance distribution of preexisting genetic structure; (3) strong demographic variations within the Mediterranean basin have affected genetic variation sufficiently to bias detected patterns of population structure. Our results suggest that bottlenose dolphin exhibits population structures that correspond well to the main Mediterranean oceanographic basins. Furthermore, we found evidence for fine scale population division within the Adriatic and the Levantine seas. We further describe for the first time, a distinction between populations inhabiting pelagic and coastal regions within the Mediterranean. Phylogeographic analysis suggests that current genetic structure, results mostly from stochastic distribution of Atlantic genetic variation, during a recent postglacial expansion. Comparison with Atlantic mtDNA haplotypes, further suggest the existence of a metapopulation across North Atlantic/Mediterranean, with pelagic regions acting as source for coastal environments

Production of Poly(vinylalcohol) Nanoyarns Using a Special Saw-like Collector

This work introduces an electrospinning method for laboratory-scale production of nanofibrous materials from polyvinylalcohol (PVA) nanofibres. A procedure for the subsequent production of twisted yarns from the aligned nanofibrous strand is introduced as well. Both needle and needleless electrospinning variants were employed. Mechanical properties of the nanoyarns produced were tested using a VIBRODYN 400 and their morphology was investigated by light and electron microscopy. The work also introduces a simple analysis of the field strength that causes the prevailing unidirectional fiber deposition between neighbouring lamellae of a special saw-like collector. The field strength analysis was carried out both analytically and by modelling based on the software COMSOL Multiphysics.Praca przedstawia metodę elektroprzędzenia do produkcji materiałów nanowłóknistych z nanowłókien PVA w skali laboratoryjnej. Przedstawiono również procedurę późniejszego wytwarzania skręconych przędz z połączonych taśm nanowłókien. W badaniach zastosowano elektroprzędzenie filierowe jaki i bezfilierowe. Właściwości mechaniczne wytworzonych przędz badano stosując VIBRODYN 400, ich morfologię badano za pomocą mikroskopii optyczna i elektronowej. Praca przedstawia również prostą analizę natężenia pola, która prowadzi do dominującego jednokierunkowego osadzania się włókien między sąsiadującymi lamelami specjalnego kolektora. Analizę natężenia pola przeprowadzono analitycznie i modelowo stosując program COMSOL Multiphysics

Charge Characterization Of An Electrically Charged Fiber Via Electrostatic Force Microscopy

The charge of a corona charged electret fiber as well as an uncharged glass fiber was characterized via Electrostatic Force Microscopy (EFM). Electrostatic force gradient images were obtained by monitoring the shifts in phase between the oscillations of the biased EFM cantilever and those of a piezoelectric driver. EFM measurements were performed using noncontact scans at a constant tip-sample separation of 75 nm with varied bias voltages applied to the cantilever. A mathematical expression, based on the Coulombic and induced polarization effects, were used to model the EFM phase shifts as a function of the applied tip bias voltages. There was quantitative agreement between the experimental data and the mathematical expression, and the quantitative interpretation for charges on the fiber was made

Acid–Base Polymeric Foams for the Adsorption of Micro-oil Droplets from Industrial Effluents

Separation of toxic organic pollutants from industrial effluents is a great environmental challenge. Herein, an acid–base engineered foam is employed for separation of micro-oil droplets from an aqueous solution. In acidic or basic environments, acid–base polymers acquire surface charge due to protonation or dissociation of surface active functional groups. This property is invoked to adsorb crude oil microdroplets from water using polyester polyurethane (PESPU) foam. The physicochemical surface properties of the foam were characterized using X-ray photoelectron spectroscopy, inverse gas chromatography, electrokinetic analysis, and micro-computed tomography. Using the surface charge of the foam and oil droplets, the solution pH (5.6) for maximum separation efficacy was predicted. This optimal pH was verified through underwater wetting behavior and adsorption experiments. The droplet adsorption onto the foam was governed by physisorption, and the driving forces were attributed to electrostatic attraction and Lifshitz–van der Waals forces. The foam was regenerated and reused multiple times by simple compression. The lowest trace oil content in the retentate was 3.6 mg L^–1, and all oil droplets larger than 140 nm were removed. This work lays the foundation for the development of a new class of engineered foam adsorbents with the potential to revolutionize water treatment technologies

Cotton Fabric Functionalized with a β‑Cyclodextrin Polymer Captures Organic Pollutants from Contaminated Air and Water

Cotton fabric is covalently functionalized with a porous β-cyclodextrin polymer by including the fabric in the polymerization mixture. The resulting functionalized fabric (CD-TFP@cotton) sequesters organic micropollutants, such as bisphenol A, from water with outstanding speed and a capacity 10-fold higher than that of untreated cotton. The functionalized fabric also readily captures volatile organic compounds (VOCs) from the vapor phase more quickly and with a capacity higher than that of untreated cotton as well as three commercially available fabric-based adsorbents. Volatile adsorbed pollutants were fully extracted from CD-TFP@cotton under reduced pressure at room temperature, permitting simple reuse. These properties make cotton functionalized with the cyclodextrin polymer of interest for water purification membranes, odor controlling fabrics, and respirators that control exposure to VOCs. This functionalization approach is scalable, likely to be amenable to other fibrous substrates, and compatible with existing fiber manufacturing techniques

Sonotherapy in the Reduction of Anxiety and Postoperative Pain in Patients With Regional Anesthesia as a Sole Technique: Randomized, Controlled Clinical Trial

OBJECTIVE: To determine if sonotherapy reduces the anxiety level and postoperative pain in adults undergoing outpatient orthopedic surgery under regional anesthesia. METHOD: A randomized, double-blind, placebo-controlled study in 80 adult patients undergoing orthopedic surgery, 40 received intervention with sonotherapy and 40 did not receive it. Pain, anxiety in the preoperative period, immediate postoperative, high, 24 and 48 hours later were measured. Hemodynamic parameters were measured in four moments. RESULTS: No significant differences were found between the two groups in the pain scales neither anxiety. A significant reduction of the systolic blood pressure was observed after the application of sonotherapy and in recovery. There was no difference in other hemodynamic variables such as heart rate, respiratory rate, arterial oxygen saturation or diastolic blood pressure between groups, however, the observed changes in some of them occurred faster in the intervention group. CONCLUSIONS: In adult patients undergoing outpatient orthopaedic surgery under regional anaesthesia, sound therapy is a novel strategy that significantly reduces systolic blood pressure, considered as an indicator of decreased anxiety. However, in our study, no difference could be demonstrated in terms of pain control or the need for additional sedation or analgesia