The content of a bacterial consortium found on an electron beam (e-beam) Pt-deposited electrode in a mediator-less microbial fuel cell (MFC) using glucose and glutamate as fuel is reported in this paper. The e-beam Pt-deposited electrode and electrochemically active bacteria (EAB) consortium were developed to improve the mediator-less MFC performance. Denaturing gradient gel electrophoresis (DGGE), restriction fragment length polymorphism (RFLP), and 16S rRNA sequencing were used to identify the EAB consortia. Sequencing results showed that clone ASP-31 was predominant and was similar to Aeromonas hydrophila, an Fe(III)-reducing and EAB. The phylogenetic tree analysis disclosed the presence of gamma-proteobacteria groups such as Aeromonas genus, Enterobacter asburiae, and Klebsiella oxytoca. These results suggest that MFC performance of the e-beam Pt-deposited electrode with Aeromonas genus consortia dominated by A. hydrophila was higher than other MFCs within a short period. With the e-beam Pt-deposited electrode and Aeromonas genus consortia in the mediator-less MFC, it is possible to increase the efficiency of electron transfer between the bacteria and the electrode.

Background: Young oncologists are at particular risk of professional burnout, and this could have a significant impact on their health and care of their patients. The coronavirus disease 2019 (COVID-19) pandemic has forced rapid changes in professionals' jobs and training, with the consequent physical and psychological effects. We aimed to characterize burnout levels and determinants in young oncologists, and the effects of the pandemic on their training and health. Methods: Two online surveys were conducted among oncology residents and young oncology specialists in Spain. The first addressed professional burnout and its determinants before the COVID-19 pandemic, while the second analyzed the impact of the pandemic on health care organization, training, and physical and psychological health in the same population. Results: In total, 243 respondents completed the first survey, and 263 the second; 25.1% reported significant levels of professional burnout. Burnout was more common among medical oncology residents (28.2%), mainly in their second year of training. It was significantly associated with a poor workelife balance, inadequate vacation time, and the burnout score. Nearly three-quarters of respondents (72%) were reassigned to COVID-19 care and 84.3% of residents missed part of their training rotations. Overall, 17.2% of this population reported that they had contracted COVID-19, 37.3% had scores indicating anxiety, and 30.4% moderate to severe depression. Almost a quarter of young oncologists (23.3%) had doubts about their medical vocation. Conclusions: Burnout affects a considerable number of young oncologists. The COVID-19 pandemic has had a profound impact on causes of burnout, making it even more necessary to periodically monitor it to define appropriate detection and prevention strategies.

Abstract:The formation of biofilm-electrodes is crucial for microbial fuel cell current production because optimal performance is often associated with thick biofilms. However, the influence of the electrode structure and morphology on biofilm formation is only beginning to be investigated. This study provides insight on how changing the electrode morphology affects current production of a pure culture of anode-respiring bacteria. Specifically, an analysis of the effects of carbon fiber electrodes with drastically different morphologies on biofilm formation and anode respiration by a pure culture (Shewanella oneidensis MR-1) were examined. Results showed that carbon nanofiber mats had ~10 fold higher current than plain carbon microfiber paper and that the increase was not due to an increase in electrode surface area, conductivity, or the size of the constituent material. Cyclic voltammograms reveal that electron transfer from the carbon nanofiber mats was biofilm-based suggesting that decreasing the diameter of the constituent carbon material from a few microns to a few OPEN ACCESSEnergies 2015, 8 1818 hundred nanometers is beneficial for electricity production solely because the electrode surface creates a more relevant mesh for biofilm formation by Shewanella oneidensis MR-1.

We report a characterization and evaluation of a single-wall carbon nanotube (SWNT) sheet electrode with infused platinum nanoparticles (nPts) as a cathode in a microbial fuel cell. The design is intended to increase electrode efficiency by increasing the surface/volume ratio and the available surface area of a platinum catalyst. The electrode fabrication procedure is an extension of the conventional bucky-paper-like fabrication technique to a two-component system and incorporates nPts throughout the thickness of the sample. The electrodes were characterized via scanning electron microscopy (SEM), Raman spectroscopy, transmission electron microscopy (TEM), and cyclic voltammetry (CV). Our characterizations confirmed the architecture of the electrodes, and the current density from our microbial fuel cell (MFC) increased significantly, approximately an order of magnitude, when an e-beam-evaporated platinum cathode was replaced with this SWNT/nPt sheet electrode. The enhancement of catalytic activity can be associated with the increase of the catalyst surface area in the active cathode layer. Finally, our data suggest that nanoparticles co-deposited into layers of nanotubes can more efficiently catalyze the cathodic reaction than electrode architectures of conventional design.

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in the department of Mechanical Engineering and Materials Science. His research interests are focused in the areas of computational simulation, additive manufacturing techniques and soft tissue biomechanics. He has broad industrial experience in materials processing, mechanical design and constitutive material model development. Dr. Schmidt is active is in the advancement of undergraduate education through the development of innovative active learning methods.

The demand for ultrasensitive and inexpensive biosensors is always strong due to increasing healthcare related concerns. Herein, we developed a simple method to prepare uniform, reliable, high yield, and low-cost two-dimensional (2-D) polyaniline layer for biosensor applications. The 2-D PANI layer's surface morphology led to a 46% increase in surface area compared to a flat 2-D surface. Due to this unique morphology and excellent semiconducting properties, the 2-D PANI layer exhibited ultrasensitive performance with excellent specificity on BNP biomarker detection in fixed Debye length condition, which is comparable to or even higher than 1-D nanostructure biosensors. In further Debye length investigation, we have observed signal changes that are varied from 8 nA to 16 nA with Debye length changes from 0.5 nm to 3.3 nm for constant BNP concentration. This result shows an improvement in device sensitivity over increasing Debye length, which conforms to Debye screening theory. With the high specificity of over 400 fold, the PANI layer was capable of monitoring significantly low BNP levels in human serum, as low as 50 pg/ml. Our findings provide an opportunity for the realization of ultrasensitive and inexpensive biosensors for clinical use.