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https://www.readbyqxmd.com/read/28100792/evolutionary-history-of-the-asian-horned-frogs-megophryinae-integrative-approaches-to-timetree-dating-in-the-absence-of-a-fossil-record
#1
Stephen Mahony, Nicole M Foley, S D Biju, Emma C Teeling
Molecular dating studies typically need fossils to calibrate the analyses. Unfortunately, the fossil record is extremely poor or presently non-existent for many species groups, rendering such dating analysis difficult. One such group is the Asian horned frogs (Megophryinae). Sampling all generic nomina, we combined a novel ∼5kb dataset composed of four nuclear and three mitochondrial gene fragments to produce a robust phylogeny, with an extensive external morphological study to produce a working taxonomy for the group...
January 18, 2017: Molecular Biology and Evolution
https://www.readbyqxmd.com/read/28100708/the-origin-of-floral-organ-identity-quartets
#2
Philip Ruelens, Zhicheng Zhang, Hilda van Mourik, Steven Maere, Kerstin Kaufmann, Koen Geuten
The origin of flowers has puzzled plant biologists ever since Darwin referred to their sudden appearance in the fossil record as an abominable mystery. Flowers are considered to be an assembly of protective, attractive and reproductive male and female leaf-like organs. Their origin cannot be understood by a morphological comparison to gymnosperms, their closest relatives, which develop separate male or female cones. Despite these morphological differences, gymnosperms and angiosperms possess a similar genetic toolbox consisting of phylogenetically related MADS-domain proteins...
January 18, 2017: Plant Cell
https://www.readbyqxmd.com/read/28097072/aggregations-and-parental-care-in-the-early-triassic-basal-cynodonts-galesaurus-planiceps-and-thrinaxodon-liorhinus
#3
Sandra C Jasinoski, Fernando Abdala
Non-mammaliaform cynodonts gave rise to mammals but the reproductive biology of this extinct group is still poorly known. Two exceptional fossils of Galesaurus planiceps and Thrinaxodon liorhinus, consisting of juveniles closely associated with an adult, were briefly described more than 50 years ago as examples of parental care in non-mammaliaform cynodonts. However, these two Early Triassic fossils have largely been excluded from recent discussions of parental care in the fossil record. Here we re-analyse these fossils in the context of an extensive survey of other aggregations found in these two basal cynodont taxa...
2017: PeerJ
https://www.readbyqxmd.com/read/28094155/sustainable-options-for-the-utilization-of-solid-residues-from-wine-production
#4
Nansen Zhang, Andrew Hoadley, Jim Patel, Seng Lim, Chao'en Li
The efficient use of solid organic waste materials is an issue of particular importance for the wine industry. This paper focuses on the valorization of grape marc, the major component of winery organic waste (60-70%). Two methods were designed and compared: combustion to generate electricity, and the pyrolysis for the production of bio-char, bio-oil, and bio-gas. Each of these processes was analysed to determine their economic and environmental viability. The flow-sheeting software, ASPEN PLUS, was used to model the two cases...
January 13, 2017: Waste Management
https://www.readbyqxmd.com/read/28094004/the-vertebrae-and-ribs-of-homo-naledi
#5
Scott A Williams, Daniel García-Martínez, Markus Bastir, Marc R Meyer, Shahed Nalla, John Hawks, Peter Schmid, Steven E Churchill, Lee R Berger
Hominin evolution featured shifts from a trunk shape suitable for climbing and housing a large gut to a trunk adapted to bipedalism and higher quality diets. Our knowledge regarding the tempo, mode, and context in which these derived traits evolved has been limited, based largely on a small-bodied Australopithecus partial skeleton (A.L. 288-1; "Lucy") and a juvenile Homo erectus skeleton (KNM-WT 15000; "Turkana Boy"). Two recent discoveries, of a large-bodied Australopithecus afarensis (KSD-VP-1/1) and two Australopithecus sediba partial skeletons (MH1 and MH2), have added to our understanding of thorax evolution; however, little is known about thorax morphology in early Homo...
January 13, 2017: Journal of Human Evolution
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/28091679/sustainability-of-renewable-fuel-infrastructure-a-screening-lca-case-study-of-anticorrosive-graphene-oxide-epoxy-liners-in-steel-tanks-for-the-storage-of-biodiesel-and-its-blends
#7
Govinda Chilkoor, Venkata K K Upadhyayula, Venkataramana Gadhamshetty, Nikhil Koratkar, Mats Tysklind
Biodiesel is a widely used fuel that meets the renewable fuel standards developed under the Energy Policy Act of 2005. However, biodiesel is known to pose a series of abiotic and biotic corrosion risks to storage tanks. A typical practice (incumbent system) used to protect the tanks from these risks include (i) coating the interior surface of the tank with a solvent-free epoxy (SFE) liner, and (ii) adding a biocide to the tank. Herein, we present a screening-level life-cycle assessment study to compare the environmental performance of a graphene oxide (GO)-epoxy (GOE) liner with the incumbent system...
January 16, 2017: Environmental Science. Processes & Impacts
https://www.readbyqxmd.com/read/28091552/dual-sources-of-water-overprinting-on-the-low-zircon-%C3%AE-18-o-metamorphic-country-rocks-disequilibrium-constrained-through-inverse-modelling-of-partial-reequilibration
#8
Chun-Sheng Wei, Zi-Fu Zhao
Since water is only composed of oxygen and hydrogen, δ(18)O and δ(2)H values are thus utilized to trace the origin of water(s) and quantify the water-rock interactions. While Triassic high pressure (HP) and ultrahigh pressure (UHP) metamorphic rocks across the Dabie-Sulu orogen in central-eastern China have been well documented, postcollisional magmatism driven hydrothermal systems are little known. Here we show that two sources of externally derived water interactions were revealed by oxygen isotopes for the gneissic country rocks intruded by the early Cretaceous postcollisional granitoids...
January 16, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28089793/eggshell-palaeogenomics-palaeognath-evolutionary-history-revealed-through-ancient-nuclear-and-mitochondrial-dna-from-madagascan-elephant-bird-aepyornis-sp-eggshell
#9
Alicia Grealy, Matthew Phillips, Gifford Miller, M Thomas P Gilbert, Jean-Marie Rouillard, David Lambert, Michael Bunce, James Haile
Palaeognaths, the sister group of all other living birds (neognaths), were once considered to be vicariant relics from the breakup of the Gondwanan supercontinent. However, recent molecular studies instead argue for dispersal of volant ancestors across marine barriers. Resolving this debate hinges upon accurately reconstructing their evolutionary relationships and dating their divergences, which often relies on phylogenetic information from extinct relatives and nuclear genomes. Mitogenomes from the extinct elephant birds of Madagascar have helped inform the palaeognath phylogeny; however, nuclear information has remained unavailable...
January 9, 2017: Molecular Phylogenetics and Evolution
https://www.readbyqxmd.com/read/28089203/carbon-footprint-and-energy-use-of-food-waste-management-options-for-fresh-fruit-and-vegetables-from-supermarkets
#10
Mattias Eriksson, Johanna Spångberg
Food waste is a problem with economic, environmental and social implications, making it both important and complex. Previous studies have addressed food waste management options at the less prioritised end of the waste hierarchy, but information on more prioritised levels is also needed when selecting the best available waste management options. Investigating the global warming potential and primary energy use of different waste management options offers a limited perspective, but is still important for validating impacts from the waste hierarchy in a local context...
January 11, 2017: Waste Management
https://www.readbyqxmd.com/read/28089136/recent-insights-into-biohydrogen-production-by-microalgae-from-biophotolysis-to-dark-fermentation
#11
REVIEW
Dillirani Nagarajan, Duu-Jong Lee, Akihiko Kondo, Jo-Shu Chang
One of the best options to alleviate the problems associated with global warming and climate change is to reduce burning of fossil fuels and search for new alternative energy resources. In case of biodiesel and bioethanol production, the choice of feedstock and the process design influences the GHG emissions and appropriate methods need to be adapted. Hydrogen is a zero-carbon and energy dense alternative energy carrier with clean burning properties and biohydrogen production by microalgae can reduce production associated GHG emissions to a great extent...
December 30, 2016: Bioresource Technology
https://www.readbyqxmd.com/read/28081508/historical-variation-in-black-carbon-deposition-and-sources-to-northern-china-sediments
#12
Wenxue Xu, Fu Wang, Jiwei Li, Lizhu Tian, Xingyu Jiang, Jilong Yang, Bing Chen
Black carbon (BC) in fine particulate matter (PM2.5) is an important air pollutant in a large area of China. We have reconstructed a 100-year-long history of BC deposition based on analyses of sediment samples in the coastal area of the Northern China Plain (NCP). During 1900-2010, the sedimentary BC concentrations at three cores increased from 0.2 to 1.3, from 0.2 to 2.3, and from 0.2 to 1.9 mg g(-1), and the ranges for the BC deposition fluxes were 0.1-4.7, 0.1-8.2, 0.2-7.4 g m(-2) a(-1), suggesting the increase of ten times from the pre-industrial era...
January 2, 2017: Chemosphere
https://www.readbyqxmd.com/read/28081386/effects-of-biodiesel-made-from-swine-and-chicken-fat-residues-on-co-co2-and-nox-emissions
#13
Vivian Feddern, Anildo Cunha Junior, Marina C De Prá, Marcio L Busi da Silva, Rodrigo da S Nicoloso, Martha M Higarashi, Arlei Coldebella, Paulo G de Abreu
Implications Emissions from motor vehicles can contribute considerably to the levels of greenhouse gases in the atmosphere. The use of biodiesel to replace or augment diesel can not only decrease our dependency on fossil fuels but also help decrease air pollution. Thus, different sources of feedstocks are constantly being explored for affordable biodiesel production. However, the amount of CO, CO2 and/or NOx emissions can vary largely depending on type of feedstock used to produce biodiesel. In this work we demonstrated animal fat feasibility in replacing petrodiesel with less impact regarding greenhouse gas emissions than other sources...
January 12, 2017: Journal of the Air & Waste Management Association
https://www.readbyqxmd.com/read/28079191/enhanced-radiation-tolerant-oxide-dispersion-strengthened-steel-and-its-microstructure-evolution-under-helium-implantation-and-heavy-ion-irradiation
#14
Chenyang Lu, Zheng Lu, Xu Wang, Rui Xie, Zhengyuan Li, Michael Higgins, Chunming Liu, Fei Gao, Lumin Wang
The world eagerly needs cleanly-generated electricity in the future. Fusion reactor is one of the most ideal energy resources to defeat the environmental degradation caused by the consumption of traditional fossil energy. To meet the design requirements of fusion reactor, the development of the structural materials which can sustain the elevated temperature, high helium concentration and extreme radiation environments is the biggest challenge for the entire material society. Oxide dispersion strengthened steel is one of the most popular candidate materials for the first wall/blanket applications in fusion reactor...
January 12, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28078735/manganese-catalyzed-multicomponent-synthesis-of-pyrimidines-from-alcohols-and-amidines
#15
Nicklas Deibl, Rhett Kempe
The development of catalytic reactions for synthesizing different compounds from alcohols to save fossil carbon feedstock and reduce CO2 emissions is of high importance. Replacing rare noble metals with abundantly available 3d metals is equally important. We report a manganese-complex-catalyzed multicomponent synthesis of pyrimidines from amidines and up to three alcohols. Our reaction proceeds through condensation and dehydrogenation steps, permitting selective C-C and C-N bond formations. β-Alkylation reactions are used to multiply alkylate secondary alcohols with two different primary alcohols to synthesize fully substituted pyrimidines in a one-pot process...
January 12, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/28078400/characterization-of-four-endophytic-fungi-as-potential-consolidated-bioprocessing-hosts-for-conversion-of-lignocellulose-into-advanced-biofuels
#16
Weihua Wu, Ryan W Davis, Mary Bao Tran-Gyamfi, Alan Kuo, Kurt LaButti, Sirma Mihaltcheva, Hope Hundley, Mansi Chovatia, Erika Lindquist, Kerrie Barry, Igor V Grigoriev, Bernard Henrissat, John M Gladden
Recently, several endophytic fungi have been demonstrated to produce volatile organic compounds (VOCs) with properties similar to fossil fuels, called "mycodiesel," while growing on lignocellulosic plant and agricultural residues. The fact that endophytes are plant symbionts suggests that some may be able to produce lignocellulolytic enzymes, making them capable of both deconstructing lignocellulose and converting it into mycodiesel, two properties that indicate that these strains may be useful consolidated bioprocessing (CBP) hosts for the biofuel production...
January 12, 2017: Applied Microbiology and Biotechnology
https://www.readbyqxmd.com/read/28077930/before-the-freeze-otoliths-from-the-eocene-of-seymour-island-antarctica-reveal-dominance-of-gadiform-fishes-teleostei
#17
Werner Schwarzhans, Thomas Mörs, Andrea Engelbrecht, Marcelo Reguero, Jürgen Kriwet
The first record of fossil teleostean otoliths from Antarctica is reported. The fossils were obtained from late Early Eocene shell beds of the La Meseta Formation, Seymour Island that represent the last temperate marine climate phase in Antarctica prior to the onset of cooling and subsequent glaciation during the late Eocene. A total of 17 otolith-based teleost taxa are recognized, with 10 being identifiable to species level containing nine new species and one new genus: Argentina antarctica sp. nov., Diaphus? marambionis sp...
2017: Journal of Systematic Palaeontology
https://www.readbyqxmd.com/read/28077871/hyoliths-are-palaeozoic-lophophorates
#18
Joseph Moysiuk, Martin R Smith, Jean-Bernard Caron
Hyoliths are abundant and globally distributed 'shelly' fossils that appear early in the Cambrian period and can be found throughout the 280 million year span of Palaeozoic strata. The ecological and evolutionary importance of this group has remained unresolved, largely because of their poorly constrained soft anatomy and idiosyncratic scleritome, which comprises an operculum, a conical shell and, in some taxa, a pair of lateral spines (helens). Since their first description over 175 years ago, hyoliths have most often been regarded as incertae sedis, related to molluscs or assigned to their own phylum...
January 19, 2017: Nature
https://www.readbyqxmd.com/read/28077210/spatial-temporal-and-multi-media-variations-of-polycyclic-aromatic-hydrocarbons-in-a-highly-urbanized-river-from-south-china
#19
Di Zhang, Jun-Jian Wang, Hong-Gang Ni, Hui Zeng
Comprehensive studies on polycyclic aromatic hydrocarbons (PAHs) within an urban river are urgently needed to carry out strategies to limit their contamination and dispersal. Here, we analyzed 16 PAH occurrences in water, suspended particulate matter (SPM), and sediment monthly for a year in the Maozhou River mainstream (Shenzhen, South China). Monthly rainfall positively correlated with both total PAH concentrations in filtered water (water PAHs) and SPM. Sediment PAH concentration increased from the river source to estuary...
January 8, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28076427/biting-midges-diptera-ceratopogonidae-from-cambay-amber-indicate-that-the-eocene-fauna-of-the-indian-subcontinent-was-not-isolated
#20
Frauke Stebner, Ryszard Szadziewski, Hukam Singh, Simon Gunkel, Jes Rust
India's unique and highly diverse biota combined with its unique geodynamical history has generated significant interest in the patterns and processes that have shaped the current distribution of India's flora and fauna and their biogeographical relationships. Fifty four million year old Cambay amber from northwestern India provides the opportunity to address questions relating to endemism and biogeographic history by studying fossil insects. Within the present study seven extant and three fossil genera of biting midges are recorded from Cambay amber and five new species are described: Eohelea indica Stebner & Szadziewski n...
2017: PloS One
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