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https://www.readbyqxmd.com/read/28110139/boosting-current-generation-in-microbial-fuel-cells-by-an-order-of-magnitude-by-coating-an-ionic-liquid-polymer-on-carbon-anodes
#1
Lu Yang, Wenfang Deng, Youming Zhang, Yueming Tan, Ming Ma, Qingji Xie
Microbial fuel cells (MFCs) have attracted great attentions due to their great application potentials, but the relatively low power densities of MFCs still hinder their widespread practical applications. Herein, we report that the current generation in MFCs can be boosted by an order of magnitude, simply by coating a hydrophilic and positively charged ionic liquid polymer (ILP) on carbon cloth (CC) or carbon felt (CF). The ILP coating not only can increase the bacterial loading capacity due to the electrostatic interactions between ILP and bacterial cells, but also can improve the mediated extracellular electron transfer between the electrode and the cytochrome proteins on the outer membrane of Shewanella putrefaciens cells...
January 14, 2017: Biosensors & Bioelectronics
https://www.readbyqxmd.com/read/28104812/antibody-secreting-plasma-cells-persist-for-decades-in-human-intestine
#2
Ole J B Landsverk, Omri Snir, Raquel Bartolomé Casado, Lisa Richter, Jeff E Mold, Pedro Réu, Rune Horneland, Vemund Paulsen, Sheraz Yaqub, Einar Martin Aandahl, Ole M Øyen, Hildur Sif Thorarensen, Mehran Salehpour, Göran Possnert, Jonas Frisén, Ludvig M Sollid, Espen S Baekkevold, Frode L Jahnsen
Plasma cells (PCs) produce antibodies that mediate immunity after infection or vaccination. In contrast to PCs in the bone marrow, PCs in the gut have been considered short lived. In this study, we studied PC dynamics in the human small intestine by cell-turnover analysis in organ transplants and by retrospective cell birth dating measuring carbon-14 in genomic DNA. We identified three distinct PC subsets: a CD19(+) PC subset was dynamically exchanged, whereas of two CD19(-) PC subsets, CD45(+) PCs exhibited little and CD45(-) PCs no replacement and had a median age of 11 and 22 yr, respectively...
January 19, 2017: Journal of Experimental Medicine
https://www.readbyqxmd.com/read/28104698/periconceptional-maternal-one-carbon-biomarkers-are-associated-with-embryonic-development-according-to-the-carnegie-stages
#3
F Parisi, M Rousian, A H J Koning, S P Willemsen, I Cetin, R P M Steegers-Theunissen
STUDY QUESTION: Is periconceptional maternal one-carbon (I-C) metabolism associated with embryonic morphological development in non-malformed ongoing pregnancies? SUMMARY ANSWER: Serum vitamin B12, red blood cell (RBC) folate and plasma total homocysteine (tHcy) are associated with embryonic development according to the Carnegie stages. WHAT IS KNOWN ALREADY: Derangements in maternal I-C metabolism affect reproductive and pregnancy outcomes, as well as future health of the offspring...
January 18, 2017: Human Reproduction
https://www.readbyqxmd.com/read/28103017/co2-electroreduction-at-low-overpotential-on-oxide-derived-cu-carbons-fabricated-from-metal-organic-framework
#4
Kun Zhao, Yanming Liu, Xie Quan, Shuo Chen, Hongtao Yu
Electrochemical reduction of CO2 to chemical feedstocks is an attractive solution to prevent CO2 accumulation in atmosphere, but it remains a great challenge to develop the cost-effective catalysts. Herein, we synthesized oxide-derived Cu/carbon (OD Cu/C) catalysts by a facile carbonization of Cu-based MOF (HKUST-1). The resulting materials exhibited highly selective CO2 reduction to alcohol compounds with the total faradic efficiency of 45.2~71.2 % at -0.1 to -0.7 V vs RHE. High-yield methanol and ethanol has been achieved on OD Cu/C-1000 with the production rates of 5...
January 19, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28099004/nickel-mediated-decarbonylation-of-simple-unstrained-ketones-through-the-cleavage-of-carbon%C3%A2-carbon-bonds
#5
Toshifumi Morioka, Akihiro Nishizawa, Takayuki Furukawa, Mamoru Tobisu, Naoto Chatani
Despite advances in methods for the decarbonylation of aldehydes, the decarbonylation of ketones has met with limited success be-cause this process requires the activation of two inert carbon-carbon bonds. All of the decarbonylation reactions of simple unstained ketones reported to date require the addition of a stoichiometric rhodium complex. We report herein the nickel/N-heterocyclic car-bene-mediated decarbonylation of simple diary ketones. This reac-tion shows unique acceleration effects based on the presence of both electron-donating and electron-withdrawing groups...
January 18, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28092812/%C3%AE-14-co2-from-dark-respiration-in-plants-and-its-impact-on-the-estimation-of-atmospheric-fossil-fuel-co2
#6
Xiaohu Xiong, Weijian Zhou, Peng Cheng, Shugang Wu, Zhenchuan Niu, Hua Du, Xuefeng Lu, Yunchong Fu, George S Burr
Radiocarbon ((14)C) has been widely used for quantification of fossil fuel CO2 (CO2ff) in the atmosphere and for ecosystem source partitioning studies. The strength of the technique lies in the intrinsic differences between the (14)C signature of fossil fuels and other sources. In past studies, the (14)C content of CO2 derived from plants has been equated with the (14)C content of the atmosphere. Carbon isotopic fractionation mechanisms vary among plants however, and experimental study on fractionation associated with dark respiration is lacking...
January 13, 2017: Journal of Environmental Radioactivity
https://www.readbyqxmd.com/read/28091885/assessing-the-impact-of-preload-on-pyrite-rich-sediment-and-groundwater-quality
#7
Ohene Karikari-Yeboah, Jonas Addai-Mensah
Pyrite-rich sediments would, invariably, undergo redox reactions which would lead to acidic aqueous environment containing solubilized toxic metal species. When such sediments are subjected to preload, a technique employed by geotechnical engineers to improve the load-bearing capacity of highly compressible formation, transient flow of pore water, accompanied by acidity transfer, would occur as a response. Despite the concomitant environmental and socio-economic significance, to date, there has been limited interdisciplinary research on the underpinning geotechnical engineering and geo-environmental science issues for pyrite-rich sediments under preload...
February 2017: Environmental Monitoring and Assessment
https://www.readbyqxmd.com/read/28091668/effect-of-ammonia-on-chemical-vapour-deposition-and-carbon-nanotube-nucleation-mechanisms
#8
Clothilde A Eveleens, Alister J Page
Chemical vapour deposition (CVD) growth of carbon nanotubes is currently the most viable method for commercial-scale nanotube production. However, controlling the 'chirality', or helicity, of carbon nanotubes during CVD growth remains a challenge. Recent studies have shown that adding chemical 'etchants', such as ammonia and water, to the feedstock gas can alter the diameter and chirality of nanotubes produced with CVD. To date, this strategy for chirality control remains sub-optimal, since we have a poor understanding of how these etchants change the CVD and nucleation mechanisms...
January 16, 2017: Nanoscale
https://www.readbyqxmd.com/read/28091593/economic-development-and-forest-cover-evidence-from-satellite-data
#9
Jesús Crespo Cuaresma, Olha Danylo, Steffen Fritz, Ian McCallum, Michael Obersteiner, Linda See, Brian Walsh
Ongoing deforestation is a pressing, global environmental issue with direct impacts on climate change, carbon emissions, and biodiversity. There is an intuitive link between economic development and overexploitation of natural resources including forests, but this relationship has proven difficult to establish empirically due to both inadequate data and convoluting geo-climactic factors. In this analysis, we use satellite data on forest cover along national borders in order to study the determinants of deforestation differences across countries...
January 16, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28079075/hydroclimate-changes-across-the-amazon-lowlands-over-the-past-45-000-years
#10
Xianfeng Wang, R Lawrence Edwards, Augusto S Auler, Hai Cheng, Xinggong Kong, Yongjin Wang, Francisco W Cruz, Jeffrey A Dorale, Hong-Wei Chiang
Reconstructing the history of tropical hydroclimates has been difficult, particularly for the Amazon basin-one of Earth's major centres of deep atmospheric convection. For example, whether the Amazon basin was substantially drier or remained wet during glacial times has been controversial, largely because most study sites have been located on the periphery of the basin, and because interpretations can be complicated by sediment preservation, uncertainties in chronology, and topographical setting. Here we show that rainfall in the basin responds closely to changes in glacial boundary conditions in terms of temperature and atmospheric concentrations of carbon dioxide...
January 11, 2017: Nature
https://www.readbyqxmd.com/read/28078904/malonyl-coa-pathway-a-promising-route-for-3-hydroxypropionate-biosynthesis
#11
Changshui Liu, Yamei Ding, Mo Xian, Min Liu, Huizhou Liu, Qingjun Ma, Guang Zhao
3-Hydroxypropionate (3HP) is an attractive platform chemical, serving as a precursor to a variety of commodity chemicals like acrylate and acrylamide, as well as a monomer of a biodegradable plastic. To establish a sustainable way to produce these commercially important chemicals and materials, fermentative production of 3HP is widely investigated in recent years. It is reported that 3HP can be produced from several intermediates, such as glycerol, malonyl-CoA, and β-alanine. Among all these biosynthetic routes, the malonyl-CoA pathway has some distinct advantages, including a broad feedstock spectrum, thermodynamic feasibility, and redox neutrality...
January 12, 2017: Critical Reviews in Biotechnology
https://www.readbyqxmd.com/read/28077967/integrated-omics-analyses-reveal-the-details-of-metabolic-adaptation-of-clostridium-thermocellum-to-lignocellulose-derived-growth-inhibitors-released-during-the-deconstruction-of-switchgrass
#12
Suresh Poudel, Richard J Giannone, Miguel Rodriguez, Babu Raman, Madhavi Z Martin, Nancy L Engle, Jonathan R Mielenz, Intawat Nookaew, Steven D Brown, Timothy J Tschaplinski, David Ussery, Robert L Hettich
BACKGROUND: Clostridium thermocellum is capable of solubilizing and converting lignocellulosic biomass into ethanol. Although much of the work-to-date has centered on characterizing this microbe's growth on model cellulosic substrates, such as cellobiose, Avicel, or filter paper, it is vitally important to understand its metabolism on more complex, lignocellulosic substrates to identify relevant industrial bottlenecks that could undermine efficient biofuel production. To this end, we have examined a time course progression of C...
2017: Biotechnology for Biofuels
https://www.readbyqxmd.com/read/28077869/age-extent-and-carbon-storage-of-the-central-congo-basin-peatland-complex
#13
Greta C Dargie, Simon L Lewis, Ian T Lawson, Edward T A Mitchard, Susan E Page, Yannick E Bocko, Suspense A Ifo
Peatlands are carbon-rich ecosystems that cover just three per cent of Earth's land surface, but store one-third of soil carbon. Peat soils are formed by the build-up of partially decomposed organic matter under waterlogged anoxic conditions. Most peat is found in cool climatic regions where unimpeded decomposition is slower, but deposits are also found under some tropical swamp forests. Here we present field measurements from one of the world's most extensive regions of swamp forest, the Cuvette Centrale depression in the central Congo Basin...
January 11, 2017: Nature
https://www.readbyqxmd.com/read/28071823/total-synthesis-of-%C3%A2-strictamine-via-2-3-sigmatropic-stevens-rearrangements
#14
Tanja Gaich, Ruben Eckermann, Michael Breunig
To date, more than 100 congeners of the akuammiline alkaloid family have been isolated. Their signature structural element is a methanoquinolizidine moiety, a cage-like scaffold structurally related to adamantane. The structural variations of the family members originate from oxidative processes that mostly trigger rearrangements of the methanoquinolizidine motif. The family of the akuammiline alkaloids is best represented by strictamine. It bears the least functionalized carbon skeleton of all family members without lacking the signature structural motifs...
January 10, 2017: Chemistry: a European Journal
https://www.readbyqxmd.com/read/28069173/periconceptional-maternal-biomarkers-of-one-carbon%C3%A2-metabolism-and-embryonic-growth-trajectories-the-rotterdam-periconceptional-cohort-predict-study
#15
Francesca Parisi, Melek Rousian, Anton H J Koning, Sten P Willemsen, Irene Cetin, Eric A P Steegers, Régine P M Steegers-Theunissen
OBJECTIVE: To study the associations between the periconceptional maternal biomarkers of one-carbon metabolism and embryonic growth. DESIGN: Prospective, periconceptional hospital-based birth cohort. SETTING: Tertiary medical care center. PATIENT(S): Between 2010 and 2014, 236 women with early singleton ongoing pregnancies that resulted in 139 strictly dated spontaneous pregnancies and 97 pregnancies conceived after assisted reproductive technology...
January 6, 2017: Fertility and Sterility
https://www.readbyqxmd.com/read/28068231/establishing-evidence-based-indications-for-proton-therapy-an-overview-of-current-clinical-trials
#16
Mark V Mishra, Sameer Aggarwal, Soren M Bentzen, Nancy Knight, Minesh P Mehta, William F Regine
PURPOSE: To review and assess ongoing proton beam therapy (PBT) clinical trials and to identify major gaps. METHODS AND MATERIALS: Active PBT clinical trials were identified from clinicaltrials.gov and the World Health Organization International Clinical Trials Platform Registry. Data on clinical trial disease site, age group, projected patient enrollment, expected start and end dates, study type, and funding source were extracted. RESULTS: A total of 122 active PBT clinical trials were identified, with target enrollment of >42,000 patients worldwide...
February 1, 2017: International Journal of Radiation Oncology, Biology, Physics
https://www.readbyqxmd.com/read/28067630/novel-swine-model-of-ricin-induced-acute-respiratory-distress-syndrome
#17
Shahaf Katalan, Reut Falach, Amir Rosner, Michael Goldvaser, Tal Brosh-Nissimov, Ayana Dvir, Avi Mizrachi, Orr Goren, Barak Cohen, Yoav Gal, Anita Sapoznikov, Sharon Ehrlich, Tamar Sabo, Chanoch Kronman
Pulmonary exposure to the plant toxin ricin, leads to respiratory insufficiency and death. To date, in-depth study of the functional disorders ensuing pulmonary intoxication, a prerequisite for establishing a clinically-relevant therapeutic protocol, is hampered by the lack of an appropriate animal model. To this end, we set up the pig, as a large animal model for the comprehensive study of the multifarious clinical manifestations of pulmonary ricinosis.Here we report for the first time, the monitoring of barometric whole body plethysmography for pulmonary function tests in non-anesthetized ricin-intoxicated pigs...
January 6, 2017: Disease Models & Mechanisms
https://www.readbyqxmd.com/read/28067384/nanocaged-platforms-modification-drug-delivery-and-nanotoxicity-opening-synthetic-cages-to-release-the-tiger
#18
REVIEW
Parham Sahandi Zangabad, Mahdi Karimi, Fatemeh Mehdizadeh, Hedieh Malekzad, Alireza Ghasemi, Sajad Bahrami, Hossein Zare, Mohsen Moghoofei, Amin Hekmatmanesh, Michael R Hamblin
Nanocages (NCs) have emerged as a new class of drug-carriers, with a wide range of possibilities in multi-modality medical treatments and theranostics. Nanocages can overcome such limitations as high toxicity caused by anti-cancer chemotherapy or by the nanocarrier itself, due to their unique characteristics. These properties consist of: (1) a high loading-capacity (spacious interior); (2) a porous structure (analogous to openings between the bars of the cage); (3) enabling smart release (a key to unlock the cage); and (4) a low likelihood of unfavorable immune responses (the outside of the cage is safe)...
January 9, 2017: Nanoscale
https://www.readbyqxmd.com/read/28060486/highly-porous-rigid-rod-polyamide-aerogels-with-superior-mechanical-properties-and-unusually-high-thermal-conductivity
#19
Jarrod C Williams, Baochau N Nguyen, Linda McCorkle, Daniel Scheiman, Justin S Griffin, Stephen A Steiner, Mary Ann B Meador
We report here the fabrication of polyamide aerogels composed of poly-p-phenylene-terephthalamide, the same backbone chemistry as DuPont's Kevlar. The all-para-substituted polymers gel without the use of cross-linker and maintain their shape during processing-an improvement over the meta-substituted cross-linked polyamide aerogels reported previously. Solutions containing calcium chloride (CaCl2) and para-phenylenediamine (pPDA) in N-methylpyrrolidinone (NMP) at low temperature are reacted with terephthaloyl chloride (TPC)...
January 18, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28059763/permanent-human-occupation-of-the-central-tibetan-plateau-in-the-early-holocene
#20
M C Meyer, M S Aldenderfer, Z Wang, D L Hoffmann, J A Dahl, D Degering, W R Haas, F Schlütz
Current models of the peopling of the higher-elevation zones of the Tibetan Plateau postulate that permanent occupation could only have been facilitated by an agricultural lifeway at ~3.6 thousand calibrated carbon-14 years before present. Here we report a reanalysis of the chronology of the Chusang site, located on the central Tibetan Plateau at an elevation of ~4270 meters above sea level. The minimum age of the site is fixed at ~7.4 thousand years (thorium-230/uranium dating), with a maximum age between ~8...
January 6, 2017: Science
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