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Carbon dating

S Strong, G Liew, M Michaelides
Hereditary retinal diseases are now the leading cause of blindness certification in the working age population (age 16-64 years) in England and Wales, of which retinitis pigmentosa (RP) is the most common disorder. RP may be complicated by cystoid macular oedema (CMO), causing a reduction of central vision. The underlying pathogenesis of RP-associated CMO (RP-CMO) remains uncertain, however, several mechanisms have been proposed, including: (1) breakdown of the blood-retinal barrier, (2) failure (or dysfunction) of the pumping mechanism in the retinal pigment epithelial, (3) Müller cell oedema and dysfunction, (4) antiretinal antibodies and (5) vitreous traction...
December 2, 2016: British Journal of Ophthalmology
Carina Verónica González, María Florencia Jofré, Hernán F Vila, Markus Stoffel, Rubén Bottini, Carla Valeria Giordano
Plants have evolved an array of specific photoreceptors to acclimate to the light environment. By sensing light signals, photoreceptors modulate plant morphology, carbon- and water-physiology, crop yield and quality of harvestable organs, among other responses. Many cultural practices and crop management decisions alter light quantity and quality perceived by plants cultivated in the field. Under full sunlight, phytochromes perceive high red to far red ratios (R:FR; 1.1), whereas overhead or lateral low R:FR (below 1...
2016: PloS One
Emilia Mmbando Raila, David O Anderson
Climate change remains one of the biggest threats to life on earth to date with black carbon (BC) emissions or smoke being the strongest cause after carbon dioxide (CO2). Surprisingly, scientific evidence about black carbon emissions reduction in healthcare settings is sparse. This paper presents new research findings on the reduction of black carbon emissions from an observational study conducted at the UN Peacekeeping Operations (MINUSTAH) in Haiti in 2014. Researchers observed 20 incineration cycles, 30 minutes for each cycle of plastic and cardboard sharps healthcare waste (HCW) containers ranged from 3 to 14...
November 30, 2016: Waste Management & Research
Zhe Sun, Naoya Miyamoto, Sota Sato, Hidetoshi Tokuyama, Hiroyuki Isobe
The invention of corner units was the key factor that allowed the synthesis of cyclo-para-phenylenes with strained curved π-systems. Despite only a few scarce instances of the development of corner units to date, a variety of structural congeners have been synthesized. These preceding corner units commonly possessed directing angles of ≤90°, which enabled the macrocyclization of multiple units, up to six. In this study, we introduce an obtuse-angled corner unit for the synthesis of cyclo-para-phenylene congeners...
November 29, 2016: Chemistry, An Asian Journal
Sophie Jasinski, Alain Lécureuil, Monique Durandet, Patrick Bernard-Moulin, Philippe Guerche
Seed storage compounds are of crucial importance for human diet, feed and industrial uses. In oleo-proteaginous species like rapeseed, seed oil and protein are the qualitative determinants that conferred economic value to the harvested seed. To date, although the biosynthesis pathways of oil and storage protein are rather well-known, the factors that determine how these types of reserves are partitioned in seeds have to be identified. With the aim of implementing a quantitative genetics approach, requiring phenotyping of 100s of plants, our first objective was to establish near-infrared reflectance spectroscopic (NIRS) predictive equations in order to estimate oil, protein, carbon, and nitrogen content in Arabidopsis seed with high-throughput level...
2016: Frontiers in Plant Science
Tatiana N Nanovskaya, Cheryl Oncken, Valentina M Fokina, Richard S Feinn, Shannon M Clark, Holly West, Sunil K Jain, Mahmoud S Ahmed, Gary D V Hankins
BACKGROUND: Bupropion is used to treat depression during pregnancy. However, its usefulness as a smoking cessation aid for pregnant women is not fully known. OBJECTIVE: The objective of the study was to evaluate the preliminary efficacy of bupropion sustained release for smoking cessation during pregnancy. STUDY DESIGN: We conducted a randomized, prospective, double-blind, placebo-controlled, pilot trial. Pregnant women who smoked daily received individualized behavior counseling and were randomly assigned to a 12 week, twice-a-day treatment with 150 mg bupropion sustained release or placebo...
November 25, 2016: American Journal of Obstetrics and Gynecology
Joel B Mason, San Yuan Tang
The consensus of epidemiologic evidence indicates that an abundant intake of foodstuffs rich in folate conveys protection against the development of colorectal cancer, and perhaps some other common cancers as well. Pre-clinical models substantiate that the relationship is a genuinely causal one. Pre-clinical models have also lent mechanistic insights into the biochemical and molecular pathways by which adequate folate exposure conveys these protective effects, although human studies are beginning to establish the relevance of our mechanistic understanding to human cancer biology...
November 24, 2016: Molecular Aspects of Medicine
Su Young Kim, Jun-Won Chung, Dong Kyun Park, Kwang An Kwon, Kyoung Oh Kim, Yoon Jae Kim, Jung Ho Kim
BACKGROUND AND AIMS: Endoscopy is performed with air insufflation and is usually associated with abdominal pain. It is well recognized that carbon dioxide (CO2) is absorbed more quickly into the body than air; however, to date, few studies have investigated the use of CO2 insufflation during consecutive esophagogastroduodenoscopy and colonoscopy (CEC). Thus, this study evaluated the efficacy of CO2 insufflation compared with air insufflation in CEC. METHODS: From March 2014 to April 2016, a total of 215 consecutive patients were randomly assigned to receive CO2 insufflation (CO2 group, n=108) or air insufflation (air group, n=107)...
November 23, 2016: Gastrointestinal Endoscopy
Linda Bauld, Rosemary Hiscock, Fiona Dobbie, Paul Aveyard, Tim Coleman, Jo Leonardi-Bee, Hayden McRobbie, Andy McEwen
The UK is a global leader in stop-smoking support-providing free behavioral support and cessation medication via stop smoking services (SSS) without charge to smokers. This study aimed to explore the client and service characteristics associated with abstinence 52 weeks after quitting. A prospective cohort study of 3057 SSS clients in nine different areas of England who began their quit attempt between March 2012 and March 2013 was conducted. Important determinants of long-term quitting were assessed through quit rates and multivariable logistic regression...
November 24, 2016: International Journal of Environmental Research and Public Health
Qiang-Qiang Ma, Ting Liu, Shujun Li, Jie Zhang, Xuenian Chen, Hairong Guan
Highly efficient catalytic reduction of CO2 with catecholborane has been developed by using bis(phosphinite) pincer ligated palladium thiolate complexes. Turnover frequencies up to 1780 h(-1) have been achieved at room temperature under an atmospheric pressure of CO2. These thiolate complexes represent the most efficient homogeneous catalysts known to date for the reduction of CO2 to methanol under mild conditions.
November 23, 2016: Chemical Communications: Chem Comm
Lisa M Baldini, James U L Baldini, Jim N McElwaine, Amy Benoit Frappier, Yemane Asmerom, Kam-Biu Liu, Keith M Prufer, Harriet E Ridley, Victor Polyak, Douglas J Kennett, Colin G Macpherson, Valorie V Aquino, Jaime Awe, Sebastian F M Breitenbach
Accurately predicting future tropical cyclone risk requires understanding the fundamental controls on tropical cyclone dynamics. Here we present an annually-resolved 450-year reconstruction of western Caribbean tropical cyclone activity developed using a new coupled carbon and oxygen isotope ratio technique in an exceptionally well-dated stalagmite from Belize. Western Caribbean tropical cyclone activity peaked at 1650 A.D., coincident with maximum Little Ice Age cooling, and decreased gradually until the end of the record in 1983...
November 23, 2016: Scientific Reports
Tobias Himmler, Germain Bayon, David Wangner, Frieder Enzmann, Jörn Peckmann, Gerhard Bohrmann
Authigenic carbonate build-ups develop at seafloor methane-seeps, where microbially mediated sulphate-dependent anaerobic oxidation of methane facilitates carbonate precipitation. Despite being valuable recorders of past methane seepage events, their role as archives of atmospheric processes has not been examined. Here we show that cyclic sedimentation pulses related to the Indian monsoon in concert with authigenic precipitation of methane-derived aragonite gave rise to a well-laminated carbonate build-up within the oxygen minimum zone off Pakistan (northern Arabian Sea)...
November 23, 2016: Scientific Reports
Ovais Shafi
BACKGROUND: The AD etiology is yet not properly known. Interactions among environmental factors, multiple susceptibility genes and aging, contribute to AD. This study investigates the factors that play role in causing AD and how changes in cellular pathways contribute to AD. METHODS: PUBMED database, MEDLINE database and Google Scholar were searched with no date restrictions for published articles involving cellular pathways with roles in cancers, cell survival, growth, proliferation, development, aging, and also contributing to Alzheimer's disease...
November 22, 2016: BMC Neurology
James M Wood, Hamed Sanei
Tight-gas and shale-gas systems can undergo significant depressurization during basin uplift and erosion of overburden due primarily to the natural leakage of hydrocarbon fluids. To date, geologic factors governing hydrocarbon leakage from such systems are poorly documented and understood. Here we show, in a study of produced natural gas from 1,907 petroleum wells drilled into a Triassic tight-gas system in western Canada, that hydrocarbon fluid loss is focused along distinct curvilinear pathways controlled by stratigraphic trends with superior matrix permeability and likely also structural trends with enhanced fracture permeability...
November 22, 2016: Nature Communications
Hui-Jun Hu, Qiang Sun, Zhou-Heng Ye, Xue-Jun Sun
Carbon monoxide (CO) has long been considered an environmental pollutant and a poison. Exogenous exposure to amounts of CO beyond the physiologic level of the body can result in a protective or adaptive response. However, as a gasotransmitter, endogenous CO is important for multiple physiologic functions. To date, at least seven distinct methods of delivering CO have been utilized in animal and clinical studies. In this mini-review, we summarize the exogenous CO delivery methods and compare their advantages and disadvantages...
April 2016: Medical Gas Research
E Pons-Branchu, M Roy-Barman, L Jean-Soro, A Guillerme, P Branchu, M Fernandez, E Dumont, E Douville, J L Michelot, A M Phillips
Speleothem-like deposits that develop underground in urban areas are an archive of the environmental impact of anthropic activities that has been little studied so far. In this paper, the sulfate content in shallow groundwater from northern Paris (France) is compared with the sulfur content in two 300-year-old urban carbonate deposits that grew in a historical underground aqueduct. The present-day waters of the aqueduct have very high sulfur and calcium contents, suggesting pollution from gypsum dissolution...
November 17, 2016: Science of the Total Environment
Yugo Shimizu, Hiroyuki Ogata, Susumu Goto
Polyketide synthases (PKSs) catalyze the sequential condensation of simple acetate units to produce a large class of natural products, including pharmacologically valuable compounds. PKSs are classified into three types on the basis of their domain structures; type III PKSs have the simplest domain structure, although their products have various structures and functions. The sequence-function relationship is fundamental for predicting enzyme functions, but it has not been well investigated in type III PKSs to date...
November 14, 2016: Chembiochem: a European Journal of Chemical Biology
Joanna C Carey, Jianwu Tang, Pamela H Templer, Kevin D Kroeger, Thomas W Crowther, Andrew J Burton, Jeffrey S Dukes, Bridget Emmett, Serita D Frey, Mary A Heskel, Lifen Jiang, Megan B Machmuller, Jacqueline Mohan, Anne Marie Panetta, Peter B Reich, Sabine Reinsch, Xin Wang, Steven D Allison, Chris Bamminger, Scott Bridgham, Scott L Collins, Giovanbattista de Dato, William C Eddy, Brian J Enquist, Marc Estiarte, John Harte, Amanda Henderson, Bart R Johnson, Klaus Steenberg Larsen, Yiqi Luo, Sven Marhan, Jerry M Melillo, Josep Peñuelas, Laurel Pfeifer-Meister, Christian Poll, Edward Rastetter, Andrew B Reinmann, Lorien L Reynolds, Inger K Schmidt, Gaius R Shaver, Aaron L Strong, Vidya Suseela, Albert Tietema
The respiratory release of carbon dioxide (CO2) from soil is a major yet poorly understood flux in the global carbon cycle. Climatic warming is hypothesized to increase rates of soil respiration, potentially fueling further increases in global temperatures. However, despite considerable scientific attention in recent decades, the overall response of soil respiration to anticipated climatic warming remains unclear. We synthesize the largest global dataset to date of soil respiration, moisture, and temperature measurements, totaling >3,800 observations representing 27 temperature manipulation studies, spanning nine biomes and over 2 decades of warming...
November 29, 2016: Proceedings of the National Academy of Sciences of the United States of America
Kuang-Kai Liu, Wei-Ru Qiu, Emmanuel Naveen Raj, Huei-Fang Liu, Hou-Syun Huang, Yu-Wei Lin, Chien-Jen Chang, Ting-Hua Chen, Chinpiao Chen, Huan-Cheng Chang, Jenn-Kang Hwang, Jui-I Chao
Selective macroautophagy/autophagy plays a pivotal role in the processing of foreign pathogens and cellular components to maintain homeostasis in human cells. To date, numerous studies have demonstrated the uptake of nanoparticles by cells, but their intracellular processing through selective autophagy remains unclear. Here we show that carbon-based nanodiamonds (NDs) coated with ubiquitin (Ub) bind to autophagy receptors (SQSTM1 [sequestosome 1], OPTN [optineurin], and CALCOCO2/NDP52 [calcium binding and coiled-coil domain 2]) and are then linked to MAP1LC3/LC3 (microtubule associated protein 1 light chain 3) for entry into the selective autophagy pathway...
November 15, 2016: Autophagy
Landon Oakes, Rachel Carter, Cary L Pint
For lithium-sulfur batteries to surpass the energy density of lithium-ion batteries, sulfur-containing cathodes require high sulfur loading (>70 wt%) relative to all inactive components, anchoring sites to prevent polysulfide shuttling, high capacity (>1000 mA h g(-1)), and stable cycling performance. Here we demonstrate a nanomanufacturing route to produce low-density hybrid nanomaterial electrodes that synergize the mechanical and electrical integrity of carbon nanotubes (CNTs) with the chemical defect properties of carbon nanohorns (CNHs) to produce carefully optimized properties for binder-free lithium-sulfur battery cathodes...
November 15, 2016: Nanoscale
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