Capacitive bioanodes for electricity storage in Microbial Fuel Cells

Denkend aan het opraken van de fossiele brandstoffen, wordt de noodzaak om naar hernieuwbare alternatieven te kijken alleen maar groter. Zon, wind, water en biomassa zijn al hernieuwbare bronnen die actueel gebruikt worden. Maar voor zonne-, wind- en waterenergie beperkt die discontinue aanwezigheid de verdere ontwikkeling en wordt de noodzaak voor elektriciteitsopslag benadrukt. Een andere technologie voor hernieuwbare elektriciteitsopwekking is de microbiële brandstofcel (MFC). In een MFC worden de organische bestanddelen van het afvalwater rechtstreeks in elektrische energie omgezet. MFCs zijn een opkomende technologie van de afgelopen 10 jaar en vele onderzoekers hebben onderzoek gedaan naar de verbetering van de stroomdichtheid en het vermogen. De continue verwerking van het afvalwater vraagt om opslag van het afvalwater of om opslag van de geproduceerde elektriciteit. Opslag van de elektriciteit kan bewerkstelligd worden door het combineren van een MFC met een condensator

Elephants classify human ethnic groups by odor and garment color

Animals can benefit from classifying predators or other dangers into categories, tailoring their escape strategies to the type and nature of the risk. Studies of alarm vocalizations have revealed various levels of sophistication in classification [1-5]. In many taxa, reactions to danger are inflexible, but some species can learn the level of threat presented by the local population of a predator [6-8] or by specific, recognizable individuals [9-10]. Some species distinguish several species of predator, giving differentiated warning calls and escape reactions; here we explore an animal’s classification of sub-groups within a species. We show that elephants distinguish at least two Kenyan ethnic groups, and can identify them by olfactory and color cues independently. In the Amboseli ecosystem, Kenya, Maasai warriors demonstrate virility by spearing elephants (Loxodonta africana), but Kamba agriculturalists pose little threat. Elephants showed greater fear when they detected the scent of garments previously worn by Maasai than by Kamba men, and reacted aggressively to the color associated with Maasai warriors. Elephants are therefore able to classify members of a single species into sub-groups that pose different degrees of danger

Addition of Bevacizumab to Chemotherapy in Advanced Non-Small Cell Lung Cancer: A Systematic Review and Meta-Analysis

INTRODUCTION: Recently, studies have demonstrated that the addition of bevacizumab to chemotherapy could be associated with better outcomes in patients with advanced non-small cell lung cancer (NSCLC). However, the benefit seems to be dependent on the drugs used in the chemotherapy regimens. This systematic review evaluated the strength of data on efficacy of the addition of bevacizumab to chemotherapy in advanced NSCLC. METHODS: PubMed, EMBASE, and Cochrane databases were searched. Eligible studies were randomized clinical trials (RCTs) that evaluated chemotherapy with or without bevacizumab in patients with advanced NSCLC. The outcomes included overall survival (OS), progression-free survival (PFS), response rate (RR), toxicities and treatment related mortality. Hazard ratios (HR) and odds ratios (OR) were used for the meta-analysis and were expressed with 95% confidence intervals (CI). RESULTS: We included results reported from five RCTs, with a total of 2,252 patients included in the primary analysis, all of them using platinum-based chemotherapy regimens. Compared to chemotherapy alone, the addition of bevacizumab to chemotherapy resulted in a significant longer OS (HR 0.89; 95% CI 0.79 to 0.99; p = 0.04), longer PFS (HR 0.73; 95% CI 0.66 to 0.82; p<0.00001) and higher response rates (OR 2.34; 95% CI 1.89 to 2.89; p<0.00001). We found no heterogeneity between trials, in all comparisons. There was a slight increase in toxicities in bevacizumab group, as well as an increased rate of treatment-related mortality. CONCLUSIONS: The addition of bevacizumab to chemotherapy in patients with advanced NSCLC prolongs OS, PFS and RR. Considering the toxicities added, and the small absolute benefits found, bevacizumab plus platinum-based chemotherapy can be considered an option in selected patients with advanced NSCLC. However, risks and benefits should be discussed with patients before decision making

In situ Biofilm Quantification in Bioelectrochemical Systems by using Optical Coherence Tomography

Detailed studies of microbial growth in bioelectrochemical systems (BESs) are required for their suitable design and operation. Here, we report the use of optical coherence tomography (OCT) as a tool for in situ and noninvasive quantification of biofilm growth on electrodes (bioanodes). An experimental platform is designed and described in which transparent electrodes are used to allow real‐time, 3D biofilm imaging. The accuracy and precision of the developed method is assessed by relating the OCT results to well‐established standards for biofilm quantification (chemical oxygen demand (COD) and total N content) and show high correspondence to these standards. Biofilm thickness observed by OCT ranged between 3 and 90 μm for experimental durations ranging from 1 to 24 days. This translated to growth yields between 38 and 42 mgurn:x-wiley:18645631:media:cssc201800589:cssc201800589-math-0001  gurn:x-wiley:18645631:media:cssc201800589:cssc201800589-math-0002 −1 at an anode potential of −0.35 V versus Ag/AgCl. Time‐lapse observations of an experimental run performed in duplicate show high reproducibility in obtained microbial growth yield by the developed method. As such, we identify OCT as a powerful tool for conducting in‐depth characterizations of microbial growth dynamics in BESs. Additionally, the presented platform allows concomitant application of this method with various optical and electrochemical techniques

Ceramic Microbial Fuel Cells Stack: Power generation in standard and supercapacitive mode

© 2018 The Author(s). In this work, a microbial fuel cell (MFC) stack containing 28 ceramic MFCs was tested in both standard and supercapacitive modes. The MFCs consisted of carbon veil anodes wrapped around the ceramic separator and air-breathing cathodes based on activated carbon catalyst pressed on a stainless steel mesh. The anodes and cathodes were connected in parallel. The electrolytes utilized had different solution conductivities ranging from 2.0 mScm-1 to 40.1 mScm-1, simulating diverse wastewaters. Polarization curves of MFCs showed a general enhancement in performance with the increase of the electrolyte solution conductivity. The maximum stationary power density was 3.2 mW (3.2 Wm-3) at 2.0 mScm-1 that increased to 10.6 mW (10.6 Wm-3) at the highest solution conductivity (40.1 mScm-1). For the first time, MFCs stack with 1 L operating volume was also tested in supercapacitive mode, where full galvanostatic discharges are presented. Also in the latter case, performance once again improved with the increase in solution conductivity. Particularly, the increase in solution conductivity decreased dramatically the ohmic resistance and therefore the time for complete discharge was elongated, with a resultant increase in power. Maximum power achieved varied between 7.6 mW (7.6 Wm-3) at 2.0 mScm-1 and 27.4 mW (27.4 Wm-3) at 40.1 mScm-1

Capacitive bioanodes for electricity storage in Microbial Fuel Cells

Denkend aan het opraken van de fossiele brandstoffen, wordt de noodzaak om naar hernieuwbare alternatieven te kijken alleen maar groter. Zon, wind, water en biomassa zijn al hernieuwbare bronnen die actueel gebruikt worden. Maar voor zonne-, wind- en waterenergie beperkt die discontinue aanwezigheid de verdere ontwikkeling en wordt de noodzaak voor elektriciteitsopslag benadrukt. Een andere technologie voor hernieuwbare elektriciteitsopwekking is de microbiële brandstofcel (MFC). In een MFC worden de organische bestanddelen van het afvalwater rechtstreeks in elektrische energie omgezet. MFCs zijn een opkomende technologie van de afgelopen 10 jaar en vele onderzoekers hebben onderzoek gedaan naar de verbetering van de stroomdichtheid en het vermogen. De continue verwerking van het afvalwater vraagt om opslag van het afvalwater of om opslag van de geproduceerde elektriciteit. Opslag van de elektriciteit kan bewerkstelligd worden door het combineren van een MFC met een condensator