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https://www.readbyqxmd.com/read/28922871/divergence-of-the-venom-exogene-repertoire-in-two-sister-species-of-turriconus
#1
Qing Li, Neda Barghi, Aiping Lu, Alexander E Fedosov, Pradip K Bandyopadhyay, Arturo O Lluisma, Gisela P Concepcion, Mark Yandell, Baldomero M Olivera, Helena Safavi-Hemami
The genus Conus comprises approximately 700 species of venomous marine cone snails that are highly efficient predators of worms, snails, and fish. In evolutionary terms, cone snails are relatively young with the earliest fossil records occurring in the Lower Eocene, 55 Ma. The rapid radiation of cone snail species has been accompanied by remarkably high rates of toxin diversification. To shed light on the molecular mechanisms that accompany speciation, we investigated the toxin repertoire of two sister species, Conus andremenezi and Conus praecellens, that were until recently considered a single variable species...
September 1, 2017: Genome Biology and Evolution
https://www.readbyqxmd.com/read/28922368/a-tree-of-life-based-on-ninety-eight-expressed-genes-conserved-across-diverse-eukaryotic-species
#2
Pawan Kumar Jayaswal, Vivek Dogra, Asheesh Shanker, Tilak Raj Sharma, Nagendra Kumar Singh
Rapid advances in DNA sequencing technologies have resulted in the accumulation of large data sets in the public domain, facilitating comparative studies to provide novel insights into the evolution of life. Phylogenetic studies across the eukaryotic taxa have been reported but on the basis of a limited number of genes. Here we present a genome-wide analysis across different plant, fungal, protist, and animal species, with reference to the 36,002 expressed genes of the rice genome. Our analysis revealed 9831 genes unique to rice and 98 genes conserved across all 49 eukaryotic species analysed...
2017: PloS One
https://www.readbyqxmd.com/read/28921909/first-natural-endocranial-cast-of-a-fossil-snake-cretaceous-of-patagonia-argentina
#3
Laura N Triviño, Adriana M Albino, María T Dozo, Jorge D Williams
In this study, we describe a natural endocranial cast included in a partially preserved medium-sized skull of the Upper Cretaceous South American snake Dinilysia patagonica. The endocast is composed of sedimentary filling of the cranial cavity in which the posterior brain, the vessels, the cranial nerves, and the inner ear surrounded by delicate semicircular canals, are represented. It is simple in form, with little differentiation between the three main areas (Forebrain, Midbrain and Hindbrain), and without flexures...
September 16, 2017: Anatomical Record: Advances in Integrative Anatomy and Evolutionary Biology
https://www.readbyqxmd.com/read/28921699/morphological-determinants-of-carrier-frequency-signal-in-katydids-orthoptera-a-comparative-analysis-using-biophysical-evidence
#4
Fernando Montealegre-Z, Jessica Ogden, Thorin Jonsson, Carl D Soulsbury
Male katydids produce mating calls by stridulation using specialized structures on the forewings. The right wing (RW) bears a scraper connected to a drum-like cell known as the mirror and a left wing (LW) that overlaps the RW and bears a serrated vein on the ventral side, the stridulatory file. Sound is generated with the scraper sweeping across the file, producing vibrations that are amplified by the mirror. Using this sound generator, katydids exploit a range of song carrier frequencies (CF) unsurpassed by any other insect group, with species singing as low as 600 Hz and others as high as 150 kHz...
September 16, 2017: Journal of Evolutionary Biology
https://www.readbyqxmd.com/read/28920759/spatial-distribution-of-polycyclic-aromatic-hydrocarbon-and-polychlorinated-biphenyl-sources-in-the-nakdong-river-estuary-south-korea
#5
Jun H Lee, Han J Woo, Kap S Jeong, Jeong W Kang, Jae U Choi, Eun J Jeong, Kap S Park, Dong H Lee
Our research team investigated the elemental composition and the presence of various toxic organic compounds, such as polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs), in estuary surface sediments to trace the spatial distribution of the sources of pollution deposited in Nakdong River, Busan, South Korea. The spatial patterns of elemental composition and toxic organic compounds were determined from the measurements of total organic carbon (TOC), total nitrogen, total sulfur, PAHs, and PCBs...
September 18, 2017: Journal of Environmental Science and Health. Part A, Toxic/hazardous Substances & Environmental Engineering
https://www.readbyqxmd.com/read/28917702/hominin-track-assemblages-from-okote-member-deposits-near-ileret-kenya-and-their-implications-for-understanding-fossil-hominin-paleobiology-at-1-5%C3%A2-ma
#6
Kevin G Hatala, Neil T Roach, Kelly R Ostrofsky, Roshna E Wunderlich, Heather L Dingwall, Brian A Villmoare, David J Green, David R Braun, John W K Harris, Anna K Behrensmeyer, Brian G Richmond
Tracks can provide unique, direct records of behaviors of fossil organisms moving across their landscapes millions of years ago. While track discoveries have been rare in the human fossil record, over the last decade our team has uncovered multiple sediment surfaces within the Okote Member of the Koobi Fora Formation near Ileret, Kenya that contain large assemblages of ∼1.5 Ma fossil hominin tracks. Here, we provide detailed information on the context and nature of each of these discoveries, and we outline the specific data that are preserved on the Ileret hominin track surfaces...
September 13, 2017: Journal of Human Evolution
https://www.readbyqxmd.com/read/28917701/paleoecological-insights-from-fossil-freshwater-mollusks-of-the-kanapoi-formation-omo-turkana-basin-kenya
#7
Bert Van Bocxlaer
The Early Pliocene Kanapoi Formation of the Omo-Turkana Basin consists of two fluvial/deltaic sedimentary sequences with an intermediate lacustrine sequence that was deposited in Paleolake Lonyumun, the earliest large lake in the basin. Overall, the geology and vertebrate paleontology of the Kanapoi Formation are well studied, but its freshwater mollusks, despite being a major component of the benthic ecosystem, have not been subjected to in-depth study. Here I present the first treatment of these mollusks, which have been retrieved mainly from the lacustrine but also from the upper fluvial sediments, with a focus on paleoecological implications...
September 13, 2017: Journal of Human Evolution
https://www.readbyqxmd.com/read/28916787/late-permian-wood-borings-reveal-an-intricate-network-of-ecological-relationships
#8
Zhuo Feng, Jun Wang, Ronny Rößler, Adam Ślipiński, Conrad Labandeira
Beetles are the most diverse group of macroscopic organisms since the mid-Mesozoic. Much of beetle speciosity is attributable to myriad life habits, particularly diverse-feeding strategies involving interactions with plant substrates, such as wood. However, the life habits and early evolution of wood-boring beetles remain shrouded in mystery from a limited fossil record. Here we report new material from the upper Permian (Changhsingian Stage, ca. 254-252 million-years ago) of China documenting a microcosm of ecological associations involving a polyphagan wood-borer consuming cambial and wood tissues of the conifer Ningxiaites specialis...
September 15, 2017: Nature Communications
https://www.readbyqxmd.com/read/28915458/physical-water-scarcity-metrics-for-monitoring-progress-towards-sdg-target-6-4-an-evaluation-of-indicator-6-4-2-level-of-water-stress
#9
REVIEW
D Vanham, A Y Hoekstra, Y Wada, F Bouraoui, A de Roo, M M Mekonnen, W J van de Bund, O Batelaan, P Pavelic, W G M Bastiaanssen, M Kummu, J Rockström, J Liu, B Bisselink, P Ronco, A Pistocchi, G Bidoglio
Target 6.4 of the recently adopted Sustainable Development Goals (SDGs) deals with the reduction of water scarcity. To monitor progress towards this target, two indicators are used: Indicator 6.4.1 measuring water use efficiency and 6.4.2 measuring the level of water stress (WS). This paper aims to identify whether the currently proposed indicator 6.4.2 considers the different elements that need to be accounted for in a WS indicator. WS indicators compare water use with water availability. We identify seven essential elements: 1) both gross and net water abstraction (or withdrawal) provide important information to understand WS; 2) WS indicators need to incorporate environmental flow requirements (EFR); 3) temporal and 4) spatial disaggregation is required in a WS assessment; 5) both renewable surface water and groundwater resources, including their interaction, need to be accounted for as renewable water availability; 6) alternative available water resources need to be accounted for as well, like fossil groundwater and desalinated water; 7) WS indicators need to account for water storage in reservoirs, water recycling and managed aquifer recharge...
September 12, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28913907/primate-diversification-inferred-from-phylogenies-and-fossils
#10
James P Herrera
Biodiversity arises from the balance between speciation and extinction. Fossils record the origins and disappearance of organisms, and the branching patterns of molecular phylogenies allow estimation of speciation and extinction rates, but the patterns of diversification are frequently incongruent between these two data sources. I tested two hypotheses about the diversification of primates based on ∼600 fossil species and 90% complete phylogenies of living species: 1) diversification rates increased through time; 2) a significant extinction event occurred in the Oligocene...
September 14, 2017: Evolution; International Journal of Organic Evolution
https://www.readbyqxmd.com/read/28913758/a-review-of-hydrogen-production-by-photosynthetic-organisms-using-whole-cell-and-cell-free-systems
#11
Baker A Martin, Paul D Frymier
Molecular hydrogen is a promising currency in the future energy economy due to the uncertain availability of finite fossil fuel resources and environmental effects from their combustion. It also has important uses in the production of fertilizers and platform chemicals as well as in upgrading conventional fuels. Conventional methods for producing molecular hydrogen from natural gas produce carbon dioxide and use a finite resource as feedstock. However, these issues can be overcome by using light energy from the Sun combined with microorganisms and their molecular machinery capable of photosynthesis...
September 14, 2017: Applied Biochemistry and Biotechnology
https://www.readbyqxmd.com/read/28913637/chemical-characterization-and-identification-of-pinaceae-pollen-by-infrared-microspectroscopy
#12
Boris Zimmermann
FTIR microspectroscopy, in combination with spectral averaging procedure, enables precise analysis of pollen grains for chemical characterization and identification studies of fresh and fossilised pollen in botany, ecology and palaeosciences. Infrared microspectroscopy (µFTIR) of Pinaceae pollen can provide valuable information on plant phenology, ecophysiology and paleoecology, but measurements are challenging, resulting in unreproducible spectra. The comparative analysis of µFTIR spectra belonging to morphologically different Pinaceae pollen, namely bisaccate Pinus and monosaccate Tsuga pollen, was conducted...
September 14, 2017: Planta
https://www.readbyqxmd.com/read/28912431/phylogeography-of-the-sand-dollar-genus-encope-implications-regarding-the-central-american-isthmus-and-rates-of-molecular-evolution
#13
Simon E Coppard, H A Lessios
Vicariant events have been widely used to calibrate rates of molecular evolution, the completion of the Central American Isthmus more extensively than any other. Recent studies have claimed that rather than the generally accepted date of ~3 million years ago (Ma), the Isthmus was effectively complete by the middle Miocene, 13 Ma. We present a fossil calibrated phylogeny of the new world sand dollar genus Encope, based on one nuclear and four mitochondrial genes, calibrated with fossils at multiple nodes. Present day distributions of Encope are likely the result of multiple range contractions and extinction events...
September 14, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28911664/smog-induces-oxidative-stress-and-microbiota-disruption
#14
REVIEW
Tit-Yee Wong
Smog is created through the interactions between pollutants in the air, fog, and sunlight. Air pollutants, such as carbon monoxide, heavy metals, nitrogen oxides, ozone, sulfur dioxide, volatile organic vapors, and particulate matters, can induce oxidative stress in human directly or indirectly through the formation of reactive oxygen species. The outermost boundary of human skin and mucous layers are covered by a complex network of human-associated microbes. The relation between these microbial communities and their human host are mostly mutualistic...
April 2017: Journal of Food and Drug Analysis
https://www.readbyqxmd.com/read/28910743/is-scena-a-good-approach-for-side-stream-integrated-treatment-from-an-environmental-and-economic-point-of-view
#15
Stefano Longo, Nicola Frison, Daniele Renzi, Francesco Fatone, Almudena Hospido
The environmental and economic benefits and burdens of including the first Short Cut Enhanced Nutrient Abatement (SCENA) into a real municipal wastewater treatment plant were evaluated using life cycle assessment (LCA) and life cycle cost (LCC). The implications of accomplishing nitrogen (N) removal and phosphorus (P) recovery via nitrite in the side stream were assessed taking into account the actual effluent quality improvement, the changes in the electricity and chemical consumption, N2O, CO2 and CH4 emissions and the effects of land application of biosolids, among others...
September 6, 2017: Water Research
https://www.readbyqxmd.com/read/28905262/non-sterile-fermentations-for-the-economical-biochemical-conversion-of-renewable-feedstocks
#16
REVIEW
Zhu Chen, Caixia Wan
Heavy reliance on petroleum-based products drives continuous exploitation of fossil fuels, and results in serious environmental and climate problems. To address such an issue, there is a shift from petroleum sources to renewable ones. Biochemical conversion via fermentation is a primary platform for converting renewable sources to biofuels and bulk chemicals. In order to provide cost-competitive alternatives, it is imperative to develop efficient, cost-saving, and robust fermentation processes. Non-sterile fermentation offers several benefits compared to sterile fermentation, including elimination of sterility, reduced maintenance requirements, relatively simple bioreactor design, and simplified operation...
September 13, 2017: Biotechnology Letters
https://www.readbyqxmd.com/read/28904786/phylogenetic-position-and-age-of-lake-baikal-candonids-crustacea-ostracoda-inferred-from-multigene-sequence-analyzes-and-molecular-dating
#17
Ivana Karanovic, Tatiana Ya Sitnikova
With 104 endemic species family Candonidae is one of the most diverse crustacean groups in Lake Baikal, yet their phylogenetic relationships and position in the family have not been addressed so far. Here, we study the phylogenetic position of Baikal candonids within the family and their evolutionary history using molecular markers for the first time since their original description. We choose 10 Baikal and 28 species from around the world, and three ribosomal RNA-s (18S, 28S, and 16S), and analyze individual and concatenated datasets using Bayesian Inference in MrBayes and BEAST...
September 2017: Ecology and Evolution
https://www.readbyqxmd.com/read/28904785/genomic-timetree-and-historical-biogeography-of-caribbean-island-ameiva-lizards-pholidoscelis-teiidae
#18
Derek B Tucker, Stephen Blair Hedges, Guarino R Colli, Robert Alexander Pyron, Jack W Sites
The phylogenetic relationships and biogeographic history of Caribbean island ameivas (Pholidoscelis) are not well-known because of incomplete sampling, conflicting datasets, and poor support for many clades. Here, we use phylogenomic and mitochondrial DNA datasets to reconstruct a well-supported phylogeny and assess historical colonization patterns in the group. We obtained sequence data from 316 nuclear loci and one mitochondrial marker for 16 of 19 extant species of the Caribbean endemic genus Pholidoscelis...
September 2017: Ecology and Evolution
https://www.readbyqxmd.com/read/28902894/what-determines-sclerobiont-colonization-on-marine-mollusk-shells
#19
Vanessa Ochi Agostini, Matias do Nascimento Ritter, Alexandre José Macedo, Erik Muxagata, Fernando Erthal
Empty mollusk shells may act as colonization surfaces for sclerobionts depending on the physical, chemical, and biological attributes of the shells. However, the main factors that can affect the establishment of an organism on hard substrates and the colonization patterns on modern and time-averaged shells remain unclear. Using experimental and field approaches, we compared sclerobiont (i.e., bacteria and invertebrate) colonization patterns on the exposed shells (internal and external sides) of three bivalve species (Anadara brasiliana, Mactra isabelleana, and Amarilladesma mactroides) with different external shell textures...
2017: PloS One
https://www.readbyqxmd.com/read/28901023/mosasaurs-and-snakes-have-a-periodontal-ligament-timing-and-extent-of-calcification-not-tissue-complexity-determines-tooth-attachment-mode-in%C3%A2-reptiles
#20
Aaron R H LeBlanc, Denis O Lamoureux, Michael W Caldwell
Squamates present a unique challenge to our understanding of dental evolution in amniotes because they are the only extant tooth-bearing group for which a ligamentous tooth attachment is considered to be absent. This has led to the assumption that mammals and crocodilians have convergently evolved a ligamentous tooth attachment, composed of root cementum, periodontal ligament, and alveolar bone, whereas squamates are thought to possess a single bone of attachment tissue that fuses teeth to the jaws. The identity and homology of tooth attachment tissues between squamates, crocodilians, and mammals have thus been a focal point of debate for decades...
September 12, 2017: Journal of Anatomy
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