Enhancing Bio-Electricity Generation Using Novel Model of Ceramic-Separator Microbial Fuel cell with a Laccase-Based Cathode

บทคัดย่อ เยื่อแลกเปลี่ยนโปรตอนเป็นองค์ประกอบสำคัญที่มีอิทธิพลต่อต้นทุนในการเดินระบบ การบำบัดสารปนเปื้อนในน้ำเสียและการผลิตกระแสไฟฟ้าในเทคโนโลยีเซลล์เชื้อเพลิงจุลินทรีย์ จากการศึกษาที่ผ่านมาวัสดุที่มีรูพรุนหลากหลายชนิดถูกนำมาประยุกต์ใช้ รวมถึงแผ่นเซรามิก ในงานวิจัยนี้เซลล์เชื้อเพลิงจุลินทรีย์เซรามิกรูปแบบใหม่ถูกพัฒนาขึ้น โดยใช้ขั้วแคโทดที่ผิวมีจุลินทรีย์แบบใช้อากาศเคลือบอยู่ซึ่งที่ประกอบขึ้นจากการเพาะเลี้ยงเชื้อยีสต์ Galactomyces reessii ที่ผลิตแลคเคสบนวัสดุใยมะพร้าวและวางบนแผ่นตาข่ายสเตนเลส ใช้ผ้าคาร์บอนเป็นขั้วแอโนด และใช้แผ่นเซรามิกที่มีความหนา 0.2 เซนติเมตร เป็นแผ่นกั้นประจุ ใช้น้ำเสียยางพาราที่มีความเข้มข้นซัลเฟตเริ่มต้นที่ 500 มิลลิกรัมต่อลิตร และค่าซีโอดีเริ่มต้นที่ 1,000 มิลลิกรัมต่อลิตร จากการศึกษาพบว่าระบบเซลล์เชื้อเพลิงจุลินทรีย์เซรามิกรูปแบบใหม่ที่พัฒนาขึ้นซึ่งทำการเดินระบบแบบกะ สามารถผลิตความหนาแน่นกำลังไฟฟ้าสูงสุดที่ 310.78±1.94 มิลลิวัตต์ต่อลูกบาศก์เมตร ความหนาแน่นกระแสไฟฟ้าสูงสุดที่ 3,392.09±16.07 มิลลิแอมแปร์ต่อลูกบาศก์เมตร และมีค่าความต้านทานภายในระบบเท่ากับ 330 โอห์ม ระบบนี้สามารถบำบัดซีโอดีได้ที่ร้อยละ 78.70±0.56 และบำบัดสารซัลเฟตที่ร้อยละ 88.85±0.50 ดังนั้นเซลล์เชื้อเพลิงจุลินทรีย์เซรามิกรูปแบบใหม่มีศักยภาพในการพัฒนาเพื่อใช้ในการบำบัดน้ำเสียในระดับอุตสาหกรรม คำสำคัญ: แผ่นกั้นเซรามิก ใยมะพร้าว พลังงานไฟฟ้า แลคเคส เซลล์เชื้อเพลิงจุลินทรีย์ สแตนเลส ซัลเฟต ABSTRACT In microbial fuel cell (MFC), a proton exchange membrane (PEM) is an important part that affects the cost of the operation and the performance in contaminants elimination and electricity  production. Various types of porous materials have been studied as alternatives to ion separators including ceramic. In this work, a novel model of ceramic-separator microbial fuel cell (CMFC) consisted of air-cathode based on coconut coir with laccase producing yeast Galactomyces reessii on stainless steel net, the carbon cloth anode and ceramic plate with 0.2 cm of thickness. The rubber wastewater (initial 500 mg/L sulfate concentration and 1,000 mg/L COD concentration) was used as an anolyte. The maximum power density of 310.78 ± 1.94 mW/m3, the maximum current density of 3,392.09 ± 16.07 mA/m3 and the internal resistance of 330 Ω were obtained for CMFC by laccase-based cathode under batch processing. Moreover, the COD removal of 78.70 ± 0.56% and the sulfate removal of 88.85 ± 0.50% were achieved. Hence, the ceramic-separator microbial fuel cell with a laccase-based cathode are potential candidate for the development of industrial-scale wastewater treatment plants.Keywords: Ceramic-separator, Coconut coir, Electrical energy, Laccase, Microbial fuel cell, Stainless steel, Sulfat

BRCA1 Directs the Repair Pathway to Homologous Recombination by Promoting 53BP1 Dephosphorylation

Summary: BRCA1 promotes homologous recombination (HR) by activating DNA-end resection. By contrast, 53BP1 forms a barrier that inhibits DNA-end resection. Here, we show that BRCA1 promotes DNA-end resection by relieving the 53BP1-dependent barrier. We show that 53BP1 is phosphorylated by ATM in S/G2 phase, promoting RIF1 recruitment, which inhibits resection. 53BP1 is promptly dephosphorylated and RIF1 released, despite remaining unrepaired DNA double-strand breaks (DSBs). When resection is impaired by CtIP/MRE11 endonuclease inhibition, 53BP1 phosphorylation and RIF1 are sustained due to ongoing ATM signaling. BRCA1 depletion also sustains 53BP1 phosphorylation and RIF1 recruitment. We identify the phosphatase PP4C as having a major role in 53BP1 dephosphorylation and RIF1 release. BRCA1 or PP4C depletion impairs 53BP1 repositioning, EXO1 recruitment, and HR progression. 53BP1 or RIF1 depletion restores resection, RAD51 loading, and HR in PP4C-depleted cells. Our findings suggest that BRCA1 promotes PP4C-dependent 53BP1 dephosphorylation and RIF1 release, directing repair toward HR. : Following induction of DNA double-strand break, a pro-end-joining environment is created in G2 by transient 53BP1 phosphorylation and RIF1 recruitment. Here, Isono et al. show that, if timely repair does not ensue, BRCA1 promotes 53BP1 dephosphorylation and RIF1 release, favoring repair by homologous recombination. Keywords: ATM, DNA-end resection, BRCA1, 53BP1, RIF1, PP4C, NHEJ, H

肺非結核性抗酸菌 (MOTT) 合併肺癌

金沢大学医薬保健研究域医学系From January 1997 to June 1999, we performed surgery in 17 patients with mycobacteria other than tuberculosis (MOTT), and 2 patients with lung cancer among them. Both patients had the diagnosis of MOTT by sputa bacterial cultures preoperatively, but no diagnosis of lung cancer. By computed tomography (CT) scanning, lung cancer was suspected in both patients, therefore they were performed video-assisted thoracoscopic resection of the lung. The diagnosis of malignancy was made by intraoperative frozen section of resected tissue, the patients were performed lobectomy with systematic mediiastinal lymph nodes dissection. According to increment of detection of the small peripheral lesion, infectious disease such as MOTT can be detected as small abnormal shadow by CT. However, it is difficult to distinguish malignancy from infectious disease preoperatively. Even if a preoperative diagnosis, of MOTT was made like present cases, diagnostic video-assisted thoracoscopic surgery must be performed, considering that lung cancer could combined with MOTT

Evidence of causality of low body mass index on risk of adolescent idiopathic scoliosis: a Mendelian randomization study

IntroductionAdolescent idiopathic scoliosis (AIS) is a disorder with a three-dimensional spinal deformity and is a common disease affecting 1-5% of adolescents. AIS is also known as a complex disease involved in environmental and genetic factors. A relation between AIS and body mass index (BMI) has been epidemiologically and genetically suggested. However, the causal relationship between AIS and BMI remains to be elucidated.Material and methodsMendelian randomization (MR) analysis was performed using summary statistics from genome-wide association studies (GWASs) of AIS (Japanese cohort, 5,327 cases, 73,884 controls; US cohort: 1,468 cases, 20,158 controls) and BMI (Biobank Japan: 173430 individual; meta-analysis of genetic investigation of anthropometric traits and UK Biobank: 806334 individuals; European Children cohort: 39620 individuals; Population Architecture using Genomics and Epidemiology: 49335 individuals). In MR analyses evaluating the effect of BMI on AIS, the association between BMI and AIS summary statistics was evaluated using the inverse-variance weighted (IVW) method, weighted median method, and Egger regression (MR-Egger) methods in Japanese.ResultsSignificant causality of genetically decreased BMI on risk of AIS was estimated: IVW method (Estimate (beta) [SE] = -0.56 [0.16], p = 1.8 × 10-3), weighted median method (beta = -0.56 [0.18], p = 8.5 × 10-3) and MR-Egger method (beta = -1.50 [0.43], p = 4.7 × 10-3), respectively. Consistent results were also observed when using the US AIS summary statistic in three MR methods; however, no significant causality was observed when evaluating the effect of AIS on BMI.ConclusionsOur Mendelian randomization analysis using large studies of AIS and GWAS for BMI summary statistics revealed that genetic variants contributing to low BMI have a causal effect on the onset of AIS. This result was consistent with those of epidemiological studies and would contribute to the early detection of AIS

Single-Chamber Microbial Fuel Cell with Multiple Plates of Bamboo Charcoal Anode: Performance Evaluation

In this study, three single-chamber microbial fuel cells (MFCs), each having Pt-coated carbon cloth as a cathode and four bamboo charcoal (BC) plates as an anode, were run in a fed-batch mode, individually and in series. Simulated potato-processing wastewater was used as a substrate for supporting the growth of a mixed bacterial culture. The maximum power output increased from 0.386 mW with one MFC to 1.047 mW with three MFCs connected in series. The maximum power density, however, decreased from 576 mW/m2 (normalized to the cathode area) with one MFC to 520 mW/m2 with three MFCs in series. The experimental results showed that power can be increased by connecting the MFCs in series; however, choosing low resistance BC is crucial for increasing power density

Effect of Operational Parameters on Micro Bio Fuel Cell

Microbial fuel cells (MFCs) are devices that generate electricity through oxidation of organic matter using bacteria as catalyst. In an MFC, electrons (e-), protons (H+), and carbon dioxide (CO2) are produced. Protons migrate to the cathode through media (anolyte), and electrons flow from an anode, through a conductive wire, to a cathode where H+, e-, and O2 are combined to form water (H2O). In this project, an air-cathode single chamber MFC was used, which possessed four bamboo charcoal (BC) plates as the anode and the cathode made of Pt-coated carbon felt. The MFC was fed with a diluted potato extract solution as substrate (energy source). Three MFCs were run concurrently to evaluate the effect of the number of the BC plates (anode) and the distance between the cathode and anode on the MFC performance; i.e., generation of voltage (mV), current (mA), power (mW), and power density (mW/m3 of cathode area). Results showed that the electrode distance between the cathode and anode did not affect significantly on the MFC performance, whereas the increase in the number of the BC plates generally increased the power density. The results provided the useful information in the future design of MFC systems

Coupling Microbial Fuel Cell and Hydroponic System for Electricity Generation, Organic Removal, and Nutrient Recovery via Plant Production from Wastewater

The world is predicted to face serious threats from the depletion of non-renewable energy resources, freshwater shortage, and food scarcity. Microbial fuel cells (MFCs) are innovative bio-electrochemical devices capable of directly converting chemical energy into electrical energy using microorganisms as a catalyst. This ability has been explored for generating electricity using wastewater as an energy source, while simultaneously treating wastewater. On the other hand, hydroponics is the cultivation of plants in water without soil. The goal of this study was to develop a novel integrated microbial fuel cell-hydroponic system (MFC-Hyp system) that possesses the ability to concurrently generate electricity while degrading organic pollutants (Chemical oxygen demand, COD) in wastewater, remove and recover nutrients (phosphorus, P and nitrogen, N) from the wastewater, and produce edible plants. The MFC-Hyp system developed in this study produced a power density of 250.7 mW/m2. The power density increased by approximately 19% and the phosphorus recovery increased to 7.5% in the presence of Allium tuberosum compared to 4.9% without the plant (e.g., in the control). The removal efficiencies of nitrate, phosphate, and COD are 32%, 11%, and 80%, respectively. The results indicate that the novel integrated MFC-Hyp system can remove COD from wastewater, generate electricity using wastewater as an energy source, and utilize nutrients for growing plants; however, this system requires further improvement for field implementation

An Overview of Microbial Fuel Cells within Constructed Wetland for Simultaneous Nutrient Removal and Power Generation

Water, energy, and food are indispensable for sustainable economic development. Despite nutrients, especially phosphorus and nitrogen, being essential for plant growth and thus food supplies, those present in wastewater are considered an environmental burden. While microbial fuel cells (MFCs) are receiving much interest, combining wastewater treatment with an MFC has emerged as an option for low-cost wastewater treatment. Among others, a constructed wetland (CW) coupled with an MFC (CW-MFC) has the potential to provide a low carbon footprint and low-energy wastewater treatment, as well as nutrient and energy recovery from wastewater. Findings from this review show that the organic and nutrient removal and power generation by the integrated CW-MFC systems are affected by a number of factors including the organic loading rate, hydraulic retention time, system design, plant species, dissolved oxygen, substrate/media type, influent feeding mode, electrode materials and spacing, and external resistance. This review aims to summarize the current state of the CW-MFC and related technologies with particular emphasis on organic and nutrient removal, as well as on the bioenergy recovery from different wastewaters. Despite the benefits that these technologies can offer, the interactive mechanisms between the CW and MFC in the integrated system are still unclear. Further research is needed to fully understand the CW-MFC and related systems. The results of this work provide not only an overview and insight into existing knowledge but also the future direction of the CW-MFC technologies