Electrospun Nanofibers of Immiscible Blends Containing a Fluorescence Dye: Direct Investigation of Polymer Domains

2020 ◽  
Vol 2 (11) ◽  
pp. 4647-4657
Author(s):  
Juliana Priscila Dreyer ◽  
Idejan Padilha Gross ◽  
Ismael Casagrande Bellettini ◽  
Vanderlei Gageiro Machado
Keyword(s):  
Electrospun Nanofibers ◽  
Immiscible Blends ◽  
Fluorescence Dye ◽  
Direct Investigation

The Time Course of the Aversive Conflict Signal

2015 ◽  
Vol 62 (1) ◽  
pp. 30-39 ◽  
Author(s):  
Julia Fritz ◽  
Gesine Dreisbach
Keyword(s):  
Time Course ◽  
Strong Support ◽  
Short Soas ◽  
Priming Effects ◽  
Presentation Time ◽  
Psychological Evidence ◽  
Study Participants ◽  
Direct Investigation

The idea that conflicts are aversive signals recently has gained strong support by both physiological as well as psychological evidence. However, the time course of the aversive signal has not been subject to direct investigation. In the present study, participants had to judge the valence of neutral German words after being primed with conflict or non-conflict Stroop stimuli in three experiments with varying SOA (200 ms, 400 ms, 800 ms) and varying prime presentation time. Conflict priming effects (i.e., increased frequencies of negative judgments after conflict as compared to non-conflict primes) were found for SOAs of 200 ms and 400 ms, but absent (or even reversed) with a SOA of 800 ms. These results imply that the aversiveness of conflicts is evaluated automatically with short SOAs, but is actively counteracted with prolonged prime presentation.

A Review on Electrospun Nanofibers-based Electrochemical Sensor

2015 ◽  
Vol 11 (6) ◽  
pp. 710-721 ◽  
Author(s):  
Lili Li ◽  
Pui Mun Lee ◽  
Guocheng Yang ◽  
Erjia Liu
Keyword(s):  
Electrochemical Sensor ◽  
Electrospun Nanofibers

Formulation, Characterization and In vitro Cytotoxicity of 5-Fluorouracil Loaded Polymeric Electrospun Nanofibers for the Treatment of Skin Cancer

2019 ◽  
Vol 13 (2) ◽  
pp. 114-128 ◽  
Author(s):  
Gayatri Patel ◽  
Bindu K.N. Yadav
Keyword(s):  
Skin Cancer ◽  
Basal Cell Carcinoma ◽  
Cell Viability ◽  
Cell Carcinoma ◽  
Basal Cell ◽  
Fiber Diameter ◽  
Electrospun Nanofibers ◽  
In Vitro Cytotoxicity ◽  
Fractional Factorial

Background: The purpose of this study was to formulate, characterize and conduct in vitro cytotoxicity of 5-fluorouracil loaded polymeric electrospun nanofibers for the treatment of skin cancer. The patents on electrospun nanofibers (US9393216B2), (US14146252), (WO2015003155A1) etc. helped in the selection of polymers and method for the preparation of nanofibers. Methods: In the present study, the fabrication of nanofibers was done using a blend of chitosan with polyvinyl alcohol and processed using the electrospinning technique. 5-fluorouracil with known chemotherapeutic potential in the treatment of skin cancer was used as a drug carrier. 24-1 fractional factorial screening design was employed to study the effect of independent variables like the concentration of the polymeric solution, applied voltage (kV), distance (cm), flow rate (ml / hr) on dependent variables like % entrapment efficiency and fiber diameter. Results: Scanning electron microscopy was used to characterize fiber diameter and morphology. Results showed that the fiber diameter of all batches was found in the range of 100-200 nm. The optimized batch results showed the fiber diameter of 162.7 nm with uniform fibers. The tensile strength obtained was 190±37 Mpa. Further in vitro and ex vivo drug release profile suggested a controlled release mechanism for an extended period of 24 hr. The 5-fluorouracil loaded electrospun nanofibers were found to decrease cell viability up to ≥50% over 24 hr, with the number of cells dropping by ~ 10% over 48 hr. As the cell viability was affected by the release of 5-fluorouracil, we believe that electrospun nanofibers are a promising drug delivery system for the treatment of Basal Cell Carcinoma (BCC) skin cancer. Conclusion: These results demonstrate the possibility of delivering 5-Fluorouracil loaded electrospun nanofiber to skin with enhanced encapsulation efficiency indicating the effectiveness of the formulation for the treatment of basal cell carcinoma type of skin cancer.

Electrospun nanofibers prepared using polystyrene (PS) with polymeric additives for the determination of nicotine in cigarette mainstream smoke

2014 ◽  
Vol 6 (14) ◽  
pp. 5120-5126 ◽  
Author(s):  
Zhifeng Guo ◽  
Xiaoyang Wu ◽  
Jingjing Dong ◽  
Hiudan Su ◽  
Ru Cai
Keyword(s):  
Solid Phase Extraction ◽  
Extraction Efficiency ◽  
Solid Phase ◽  
Electrospun Nanofibers ◽  
Phase Extraction ◽  
Mainstream Smoke ◽  
Polymeric Additives ◽  
Cigarette Mainstream Smoke

The objective of this paper is to use electrospun nanofibers as the adsorbents in solid phase extraction (SPE) to improve the extraction efficiency.

scholarly journals Focused Patterning of Electrospun Nanofibers Using a Dielectric Guide Structure

Polymers ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1505
Author(s):  
Byeongjun Lee ◽  
Younghyeon Song ◽  
Chan Park ◽  
Jungmin Kim ◽  
Jeongbeom Kang ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Finite Elements ◽  
Electric Field ◽  
Electrospun Nanofibers ◽  
Electrospun Fibers ◽  
Continuous Line ◽  
Key Factors ◽  
Key Technology ◽  
Vertical Electric Field ◽  
Dielectric Guide

The patterning of electrospun fibers is a key technology applicable to various fields. This study reports a novel focused patterning method for electrospun nanofibers that uses a cylindrical dielectric guide. The finite elements method (FEM) was used to analyze the electric field focusing phenomenon and ground its explanation in established theory. The horizontal and vertical electric field strengths in the simulation are shown to be key factors in determining the spatial distribution of nanofibers. The experimental results demonstrate a relationship between the size of the cylindrical dielectric guide and that of the electrospun area accumulated in the collector. By concentrating the electric field, we were able to fabricate a pattern of less than 6 mm. The demonstration of continuous line and square patterning shows that the electrospun area can be well controlled. This novel patterning method can be used in a variety of applications, such as sensors, biomedical devices, batteries, and composites.

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