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Carbon dating

I Stefani, M A Asnaghi, J J Cooper-White, S Mantero
Cardiovascular diseases represent a major global health burden, with high rates of mortality and morbidity. Autologous grafts are commonly used to replace damaged or failing blood vessels, however such approaches are hampered by the scarcity of suitable graft tissue, donor site morbidity and poor long-term stability. Tissue engineering has been investigated as a means by which exogenous vessel grafts can be produced, with varying levels of success to date, a result of mismatched mechanical properties of these vessel substitutes and inadequate ex vivo vessel tissue genesis...
October 24, 2016: Journal of Tissue Engineering and Regenerative Medicine
Hala Attia, Nouf Al-Rasheed, Raeesa Mohamad, Nawal Al-Rasheed, Maha Al-Amin
BACKGROUND: Hepatic fibrosis and its end point; cirrhosis, are the major cause of liver failure and death in patients with chronic liver disease. Therefore, the need for an effective treatment is evident. This study was designed to assess the potential effects of aqueous extract of date fruits, either flesh (DFE) or pits (DPE), on oxidative DNA damage and liver inflammation induced by carbon tetrachloride (CCl4) and whether they are related to inhibition of nuclear factor-κB pathway...
October 24, 2016: BMC Complementary and Alternative Medicine
Yoonbae Oh, Cheonho Park, Do Hyoung Kim, Hojin Shin, Yu Min Kang, Mark DeWaele, Jeyeon Lee, Hoon-Ki Min, Charles D Blaha, Kevin Bennet, In Young Kim, Kendall H Lee, Dong Pyo Jang
Dopamine (DA) modulates central neuronal activity through both phasic (second to second) and tonic (minutes to hours) terminal release. Conventional fast-scan cyclic voltammetry (FSCV), in combination with carbon fiber microelectrodes, has been used to measure phasic DA release in vivo by adopting a background subtraction procedure to remove background capacitive currents. However, to-date, measuring tonic changes in DA concentrations using conventional FSCV has been difficult because background capacitive currents are inherently unstable over long recording periods...
October 24, 2016: Analytical Chemistry
Anna Juras, Maciej Chyleński, Marta Krenz-Niedbała, Helena Malmström, Edvard Ehler, Łukasz Pospieszny, Sylwia Łukasik, Józef Bednarczyk, Janusz Piontek, Mattias Jakobsson, Miroslawa Dabert
We applied an interdisciplinary approach to investigate kinship patterns and funerary practices during the middle Neolithic. Genetic studies, radiocarbon dating, and taphonomic analyses were used to examine two grave clusters from Krusza Zamkowa, Poland. To reconstruct kinship and determine biological sex, we extracted DNA from bones and teeth, analyzed mitochondrial genomes and nuclear SNPs using the HID-Ion AmpliSeq™ Identity panel generated on Illumina and Ion Torrent platforms, respectively. We further dated the material (AMS (14)C) and to exclude aquatic radiocarbon reservoir effects, measures of carbon and nitrogen stable isotopes for diet reconstruction were used...
October 14, 2016: Forensic Science International. Genetics
Yadvinder Malhi, Cécile A J Girardin, Gregory R Goldsmith, Christopher E Doughty, Norma Salinas, Daniel B Metcalfe, Walter Huaraca Huasco, Javier E Silva-Espejo, Jhon Del Aguilla-Pasquell, Filio Farfán Amézquita, Luiz E O C Aragão, Rossella Guerrieri, Françoise Yoko Ishida, Nur H A Bahar, William Farfan-Rios, Oliver L Phillips, Patrick Meir, Miles Silman
Why do forest productivity and biomass decline with elevation? To address this question, research to date generally has focused on correlative approaches describing changes in woody growth and biomass with elevation. We present a novel, mechanistic approach to this question by quantifying the autotrophic carbon budget in 16 forest plots along a 3300 m elevation transect in Peru. Low growth rates at high elevations appear primarily driven by low gross primary productivity (GPP), with little shift in either carbon use efficiency (CUE) or allocation of net primary productivity (NPP) between wood, fine roots and canopy...
October 21, 2016: New Phytologist
Gyu Ri Hong, Sun Sook Lee, Yejin Jo, Min Jun Choi, Yun Chan Kang, Beyong-Hwan Ryu, Kwun Bum Chung, Youngmin Choi, Sunho Jeong
The solution-processable oxide semiconductors have gained the paramount attention with a possibility of forming cost-effectively semiconducting channel layers with moderate field-effect mobility for the application to thin-film transistors (TFTs). To date, a variety of compositional oxide material and post-annealing techniques have been demonstrated based on a spin-coating method, well-suited for a small-sized device fabrication along with a significant material loss in a large-area process. In this study, we report, for the first time report, a simple bar-coating process of soluble metal oxide semiconductors, consuming the 0...
October 20, 2016: ACS Applied Materials & Interfaces
Zhan Liang, Leslie A Hoffman, Mehdi Nouraie, Daniel J Kass, Michael P Donahoe, Kevin F Gibson, Melissa I Saul, Kathleen O Lindell
BACKGROUND: Palliative care has been recommended as a means to assist patients with idiopathic pulmonary fibrosis (IPF) in managing symptom burden and advanced care planning. Timing of referral is important because although most patients display a gradually progressive course, a minority experience acute deterioration, an outcome associated with high mortality. AIM: To describe characteristics of IPF patients referred to a specialty lung disease center over a 10-year period who experienced acute deterioration and subsequent intensive care unit (ICU) admission, including frequency and timing of referral to palliative care...
October 18, 2016: Journal of Palliative Medicine
Feng Hu, Hongchao Yang, Changhong Wang, Yejun Zhang, Huan Lu, Qiangbin Wang
Rational design of cost-effective, nonprecious metal-based catalysts with desirable oxygen reduction reaction (ORR) performance is extremely important for future fuel cell commercialization, etc. Herein, a new type of ORR catalyst of Co-N-doped mesoporous carbon hollow sphere (Co-N-mC) was developed by pyrolysis from elaborately fabricated polystyrene@polydopamine-Co precursors. The obtained catalysts with active Co sites distributed in highly graphitized mesoporous N-doped carbon hollow spheres exhibited outstanding ORR activity with an onset potential of 0...
October 18, 2016: Small
M'hamed Seklaoui, Abdelhak Boutaleb, Hanafi Benali, Fadila Alligui, Walter Prochaska
To date, there have been few detailed studies regarding the impact of mining and metallogenic activities on solid fractions in the Azzaba mercurial district (northeast Algeria) despite its importance and global similarity with large Hg mines. To assess the degree, distribution, and sources of pollution, a physical inventory of apparent pollution was developed, and several samples of mining waste, process waste, sediment, and soil were collected on regional and local scales to determine the concentration of Hg and other metals according to their existing mineralogical association...
November 2016: Environmental Monitoring and Assessment
Julie M Proudfoot, Anne E Barden, Kevin D Croft, Jean-M Galano, Thierry Durand, Valerie Bultel-Ponce, Martin Giera, Trevor A Mori
Low HDL cholesterol (HDL-C) is a risk factor for coronary artery disease (CAD). However, interventions that raise HDL-C have failed to reduce cardiovascular events. We previously reported that HDL is the main carrier of plasma F2-isoprostanes (F2-IsoPs) that are markers of oxidative stress formed upon oxidation of arachidonic acid. F2-IsoPs are predominantly associated with phospholipids. However, there is evidence that F2-IsoPs in the liver of rats treated with carbon tetrachloride associate with the neutral lipids...
October 17, 2016: Free Radical Research
Zhaohui Xiao, Xiaobing Huang, Lei Xu, Dafeng Yan, Jia Huo, Shuangyin Wang
The development of efficient, stable and cost-effective electrocatalysts for the oxygen evolution reaction (OER) is the key for water splitting. Carbon-based nanomaterials have found significant applications as metal-free OER electrocatalysts. In this study, for the first time, edge-selectively phosphorus-doped graphene (G-P) was synthesised for OER electrocatalysts. The G-P catalyst reached a current density of 10 mA cm(-2) at a small overpotential of 330 mV for the OER with a Tafel slope as low as 62 mV dec(-1), which is superior to most of the carbon-based electrocatalysts reported to date...
October 17, 2016: Chemical Communications: Chem Comm
Jeong Wook Lee, Jongho Yi, Tae Yong Kim, Sol Choi, Jung Ho Ahn, Hyohak Song, Moon-Hee Lee, Sang Yup Lee
Succinic acid (SA) is a four carbon dicarboxylic acid of great industrial interest that can be produced by microbial fermentation. Here we report development of a high-yield homo-SA producing Mannheimia succiniciproducens strain by metabolic engineering. The PALFK strain (ldhA(-), pta(-), ackA(-), fruA(-)) was developed based on optimization of carbon flux towards SA production while minimizing byproducts formation through the integrated application of in silico genome-scale metabolic flux analysis, omics analyses, and reconstruction of central carbon metabolism...
October 13, 2016: Metabolic Engineering
Qiang Zheng, Yanting Liu, Christian Jeanthon, Rui Zhang, Wenxin Lin, Jicheng Yao, Nianzhi Jiao
: Aerobic anoxygenic phototrophic bacteria (AAPB) are thought to be important players in oceanic carbon and energy cycling in the euphotic zone of the ocean. The genus Citromicrobium, widely found in oligotrophic oceans, is a member of marine alphaproteobacterial AAPB. Nine Citromicrobium strains isolated from the South China Sea, the Mediterranean Sea or the tropical South Atlantic were found to harbor identical 16S rRNA sequences. The sequencing of their genomes revealed high synteny in major regions...
October 7, 2016: Applied and Environmental Microbiology
Sigrun Reumann, Piotr Lisik
To date, less than 150 proteins have been located to plant peroxisomes, indicating that unbiased large-scale approaches such as experimental proteome research are required to uncover the remaining yet unknown metabolic functions of this organelle as well as its regulatory mechanisms and membrane proteins. For experimental proteome research, Arabidopsis thaliana is the model plant of choice and an isolation methodology that obtains peroxisomes of sufficient yield and high purity is vital for research on this organelle...
2017: Methods in Molecular Biology
Leah D McGurn, Maryam Moazami-Goudarzi, Sean A White, Tannu Suwal, Beant Brar, Jason Q Tang, George S Espie, Matthew S Kimber
CcaA is a b-carbonic anhydrase that is a component of the carboxysomes of a subset of b-cyanobacteria. This protein, which has a characteristic C-terminal extension of unknown function, is recruited to the carboxysome via interactions with CcmM, which is itself a γ-carbonic anhydrase homolog with enzymatic activity in many, but not all cyanobacteria. We have determined the structure of CcaA from Synechocystis sp. PCC 6803 at 1.45 Å. In contrast to the dimer of dimers organization of most bacterial β-carbonic anhydrases, or the loose dimer-of-dimers-of-dimers organization found in the plant enzymes, CcaA shows a well-packed trimer-of-dimers organization...
October 11, 2016: Biochemical Journal
Tingting Xu, Lixin Chen, Zhanhu Guo, Tingli Ma
Perovskite solar cells (PSCs) have gained tremendous research interest in recent several years. To date the power conversion efficiency (PCE) of PSCs has been increased from 3.8% to over 22.1%, showing that they have a promising future as a renewable energy resource to compete with conventional silicon solar cells. However, a crucial challenge of PSCs currently is that perovskite materials and PSCs have limitations of easy degradation and inferior long-term stabilities, thus hampering their future commercial applications...
October 5, 2016: Physical Chemistry Chemical Physics: PCCP
R G Yousuf, J B Winterburn
Poly-3-hydroxybutrate (PHB) is a biodegradable polymer synthesised via bacterial fermentation as a means of storing carbon and energy under unbalanced growth conditions. The production cost of petroleum-based plastics is currently lower than that for biopolymers, and the carbon source is the most significant contributor to biopolymer production cost. A feasibility study to assess the suitability of using a date seed derived media as an alternative for PHB production under various stress conditions was investigated...
September 29, 2016: Bioresource Technology
Zhazira Yesbergenova-Cuny, Sylvie Dinant, Marie-Laure Martin-Magniette, Isabelle Quilleré, Patrick Armengaud, Priscilla Monfalet, Peter J Lea, Bertrand Hirel
Using a metabolomic approach, we have quantified the metabolite composition of the phloem sap exudate of seventeen European and American lines of maize that had been previously classified into five main groups on the basis of molecular marker polymorphisms. In addition to sucrose, glutamate and aspartate, which are abundant in the phloem sap of many plant species, large quantities of aconitate and alanine were also found in the phloem sap exudates of maize. Genetic variability of the phloem sap composition was observed in the different maize lines, although there was no obvious relationship between the phloem sap composition and the five previously classified groups...
November 2016: Plant Science: An International Journal of Experimental Plant Biology
Juan Ma, Ruibin Li, Guangbo Qu, Huiyu Liu, Bing Yan, Tian Xia, Yajun Liu, Sijin Liu
Carbon nanotubes (CNTs) have promising applications in a wide range of biomedical fields, including imaging, drug/gene delivery and other therapeutics; however, the biosafety concerns of CNTs should be addressed. To date, many reports have documented the toxicological effects on the cells, tissue or organs that are in direct contact with the tubes; however, there is limited evidence to unravel the secondary toxicity upon CNT treatment. Moreover, more effort is needed to gain a definitive understanding of the adverse outcome pathway (AOP) for CNTs, and a pragmatic framework for risk assessment has not been established yet...
September 29, 2016: Nanoscale
Emily Meineke, Elsa Youngsteadt, Robert R Dunn, Steven D Frank
A substantial amount of global carbon is stored in mature trees. However, no experiments to date test how warming affects mature tree carbon storage. Using a unique, citywide, factorial experiment, we investigated how warming and insect herbivory affected physiological function and carbon sequestration (carbon stored per year) of mature trees. Urban warming increased herbivorous arthropod abundance on trees, but these herbivores had negligible effects on tree carbon sequestration. Instead, urban warming was associated with an estimated 12% loss of carbon sequestration, in part because photosynthesis was reduced at hotter sites...
October 12, 2016: Proceedings. Biological Sciences
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