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https://www.readbyqxmd.com/read/28738521/ginkgo-biloba-exocarp-extracts-induces-autophagy-in-lewis-lung-cancer-cells-involving-ampk-mtor-p70s6k-signaling-pathway
#1
Chenjie Cao, Dongdong Han, Ya Su, Yu Ge, Huasheng Chen, Aihua Xu
OBJECTIVES: Ginkgo biloba L. is called a living fossil plant, and could be used for the treatment of cancer thousands of years ago in China. The extracts prepared from the Ginkgo biloba exocarp (Ginkgo biloba exocarp extracts, GBEE) has a significant anti-cancer effect. Autophagy plays an important role in the occurrence and development of cancer as programmed cell death (PCD) type II. Thus it would be interesting to study the effects and mechanisms of GBEE inducing autophagy in Lewis lung cancer (LLC) cells...
July 19, 2017: Biomedicine & Pharmacotherapy, Biomédecine & Pharmacothérapie
https://www.readbyqxmd.com/read/28736808/comparative-cranial-ontogeny-of-tapirus-mammalia-perissodactyla-tapiridae
#2
S Rocio Moyano, Norberto P Giannini
Skull morphology in tapirs is particularly interesting due to the presence of a proboscis with important trophic, sensory and behavioral functions. Several studies have dealt with tapir skull osteology but chiefly in a comparative framework between fossil and recent species of tapirs. Only one study examined an aspect of cranial ontogeny, development of the sagittal crest (Holbrook. J Zool Soc Lond 2002; 256; 215). Our goal is to describe in detail the morphological changes that occur during the postnatal ontogeny of the skull in two representative tapir species, Tapirus terrestris and Tapirus indicus, and to explore possible functional consequences of their developmental trajectories...
July 24, 2017: Journal of Anatomy
https://www.readbyqxmd.com/read/28734289/perspective-photocatalytic-reduction-of-co2-to-solar-fuels-over-semiconductors
#3
Chao Peng, Glenn Reid, Haifeng Wang, P Hu
Increasing emissions of carbon dioxide and the depletion of finite fossil fuels have led to many concerns about global warming and energy crises. Consequently, a sustainable and alternative method, photocatalytic CO2 reduction to chemical fuels has received considerable attention. This perspective highlights recent knowledge and the main challenges in CO2 photoreduction primarily from the theoretical field. The fundamental understanding of CO2 adsorption and reaction mechanism at an atomic level is fully addressed, and the relevant effects dominating the process of CO2 photoreduction are also elucidated...
July 21, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/28733989/detecting-ancient-co-dispersals-and-host-shifts-by-double-dating-of-host-and-parasite-phylogenies-application-in-proctophyllodid-feather-mites-associated-with-passerine-birds
#4
Pavel B Klimov, Sergey V Mironov, Barry M OConnor
Inferring co-phylogeographic events requires matching the timing of these events on both host and symbiont (e.g., parasites) phylogenies because divergences of hosts and their symbionts may not temporally coincide, and host switches may occur. We investigate a large radiation of birds (Passeriformes) and their permanent symbionts, the proctophyllodid feather mites (117 species from 116 bird species; 6 genes, 11,468 nt aligned) using two time-calibration strategies for mites: fossils only and host phylogeography only...
July 22, 2017: Evolution; International Journal of Organic Evolution
https://www.readbyqxmd.com/read/28732402/characteristics-of-black-carbon-in-snow-from-laohugou-no-12-glacier-on-the-northern-tibetan-plateau
#5
Yulan Zhang, Shichang Kang, Chaoliu Li, Tanguang Gao, Zhiyuan Cong, Michael Sprenger, Yajun Liu, Xiaofei Li, Junming Guo, Mika Sillanpää, Kun Wang, Jizu Chen, Yang Li, Shiwei Sun
Black carbon (BC) emitted from the incomplete combustion of biomass and fossil fuel impacts the climate system, cryospheric change, and human health. This study documents black carbon deposition in snow from a benchmark glacier on the northern Tibetan Plateau. Significant seasonality of BC concentrations indicates different input or post-depositional processes. BC particles deposited in snow had a mass volume median diameter slightly larger than that of black carbon particles typically found in the atmosphere...
July 17, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28731829/pattern-and-process-in-the-comparative-study-of-convergent-evolution
#6
D Luke Mahler, Marjorie G Weber, Catherine E Wagner, Travis Ingram
Understanding processes that have shaped broad-scale biodiversity patterns is a fundamental goal in evolutionary biology. The development of phylogenetic comparative methods has yielded a tool kit for analyzing contemporary patterns by explicitly modeling processes of change in the past, providing neontologists tools for asking questions previously accessible only for select taxa via the fossil record or laboratory experimentation. The comparative approach, however, differs operationally from alternative approaches to studying convergence in that, for studies of only extant species, convergence must be inferred using evolutionary process models rather than being directly measured...
August 2017: American Naturalist
https://www.readbyqxmd.com/read/28731827/convergence-consilience-and-the-evolution-of-temperate-deciduous-forests
#7
Erika J Edwards, David S Chatelet, Bo-Chang Chen, Jin Yao Ong, Shuichiro Tagane, Hironobu Kanemitsu, Kazuki Tagawa, Kentaro Teramoto, Brian Park, Kuo-Fang Chung, Jer-Ming Hu, Tetsukazu Yahara, Michael J Donoghue
The deciduous habit of northern temperate trees and shrubs provides one of the most obvious examples of convergent evolution, but how did it evolve? Hypotheses based on the fossil record posit that deciduousness evolved first in response to drought or darkness and preadapted certain lineages as cold climates spread. An alternative is that evergreens first established in freezing environments and later evolved the deciduous habit. We monitored phenological patterns of 20 species of Viburnum spanning tropical, lucidophyllous (subtropical montane and warm temperate), and cool temperate Asian forests...
August 2017: American Naturalist
https://www.readbyqxmd.com/read/28731295/biogeochemistry-of-lead-its-release-to-the-environment-and-chemical-speciation
#8
Jay T Cullen, Jason McAlister
Lead (Pb) is a metal that is not essential for life processes and proves acutely toxic to most organisms. Compared to other metals Pb is rather immobile in the environment but still its biogeochemical cycling is greatly perturbed by human activities. In this review we present a summary of information describing the physical and chemical properties of Pb, its distribution in crustal materials, and the processes, both natural and anthropogenic, that contribute to the metal's mobilization in the biosphere. The relatively high volatility of Pb metal, low melting point, its large ionic radius, and its chemical speciation in aquatic systems contributes to its redistribution by anthropogenic and natural processes...
April 10, 2017: Metal Ions in Life Sciences
https://www.readbyqxmd.com/read/28730654/extensive-wildfires-climate-change-and-an-abrupt-state-change-in-subalpine-ribbon-forests-colorado
#9
W John Calder, Bryan Shuman
Ecosystems may shift abruptly when the effects of climate change and disturbance interact, and landscapes with regularly patterned vegetation may be especially vulnerable to abrupt shifts. Here we use a fossil pollen record from a regularly patterned ribbon forest (alternating bands of forests and meadows) in Colorado to examine whether past changes in wildfire and climate produced abrupt vegetation shifts. Comparing the percentages of conifer pollen with sedimentary δ(18) O data (interpreted as an indicator of temperature or snow accumulation) indicates a first-order linear relationship between vegetation composition and climate change with no detectable lags over the past 2500 years (r = 0...
July 21, 2017: Ecology
https://www.readbyqxmd.com/read/28728789/evaluation-of-the-environmental-sustainability-of-different-waste-to-energy-plant-configurations
#10
Lidia Lombardi, Ennio A Carnevale
Residual municipal solid waste (MSW) has an average lower heating value higher than 10GJ/Mg in the EU, and can be recovered in modern Waste-to-Energy (WtE) plants, producing combined heat and power (CHP) and reaching high levels of energy recovery. CHP is pinpointed as the best technique for energy recovery from waste. However, in some cases, heat recovery is not technically feasible - due to the absence of a thermal user (industrial plant or district heating) in the vicinity of the WtE plant - and power production remains the sole possibility...
July 17, 2017: Waste Management
https://www.readbyqxmd.com/read/28726748/effect-of-air-pollution-on-menstrual-cycle-length-a-prognostic-factor-of-women-s-reproductive-health
#11
Anna Merklinger-Gruchala, Grazyna Jasienska, Maria Kapiszewska
Air pollution can influence women's reproductive health, specifically menstrual cycle characteristics, oocyte quality, and risk of miscarriage. The aim of the study was to assess whether air pollution can affect the length of the overall menstrual cycle and the length of its phases (follicular and luteal). Municipal ecological monitoring data was used to assess the air pollution exposure during the monitored menstrual cycle of each of 133 woman of reproductive age. Principal component analyses were used to group pollutants (PM10, SO₂, CO, and NOx) to represent a source-related mixture...
July 20, 2017: International Journal of Environmental Research and Public Health
https://www.readbyqxmd.com/read/28726706/cost-assessment-of-different-routes-for-phosphorus-recovery-from-wastewater-using-data-from-pilot-and-production-plants
#12
A Nättorp, K Remmen, C Remy
Phosphorus (P) recovery from wastewater has considerable potential to supplement limited fossil P reserves. Reliable cost data are essential for investor and policymaker decisions. In this study, investment and operational costs for nine P recovery processes were calculated from the investor's perspective, taking into account all relevant side effects on the sludge treatment or the wastewater treatment plant. The assessment was based on pilot and full-scale data which were thoroughly consolidated and standardized with technical and cost data from the German wastewater-sludge treatment train to enable direct comparison...
July 2017: Water Science and Technology: a Journal of the International Association on Water Pollution Research
https://www.readbyqxmd.com/read/28725265/two-bifunctional-enzymes-from-the-marine-protist-thraustochytrium-roseum-biochemical-characterization-of-wax-ester-synthase-acyl-coa-diacylglycerol-acyltransferase-activity-catalyzing-wax-ester-and-triacylglycerol-synthesis
#13
Nannan Zhang, Zejing Mao, Ling Luo, Xia Wan, Fenghong Huang, Yangmin Gong
BACKGROUND: Triacylglycerols (TAGs) and wax esters (WEs) are important neutral lipids which serve as energy reservoir in some plants and microorganisms. In recent years, these biologically produced neutral lipids have been regarded as potential alternative energy sources for biofuel production because of the increased interest on developing renewable and environmentally benign alternatives for fossil fuels. In bacteria, the final step in TAG and WE biosynthetic pathway is catalyzed by wax ester synthase/acyl coenzyme A (acyl-CoA):diacylglycerol acyltransferase (WS/DGAT)...
2017: Biotechnology for Biofuels
https://www.readbyqxmd.com/read/28725090/european-economies-in-terms-of-energy-dependence
#14
Anna Bluszcz
The sustainable development and energy security are currently the priority challenges for the European Union countries. The sustainable and stable development of European economies is closely dependent on the stable access to energy resources. The constant increase of the demand for electricity requires long-term planning of the common European policy. The aim of the article is to analyse the fuel and energy resources situation of the member states with regard to their energy balances and with the determination of their import dependence in relation to fossil fuels, such as: coal, oil and natural gas...
2017: Quality & Quantity
https://www.readbyqxmd.com/read/28724887/first-ornithomimid-theropoda-ornithomimosauria-from-the-upper-cretaceous-djadokhta-formation-of-t%C3%A3-gr%C3%A3-giin-shiree-mongolia
#15
Chinzorig Tsogtbaatar, Yoshitsugu Kobayashi, Tsogtbaatar Khishigjav, Philip J Currie, Mahito Watabe, Barsbold Rinchen
The Upper Cretaceous Djadokhta Formation has been intensively surveyed for its fossil vertebrate fauna for nearly a century. Amongst other theropods, dromaeosaurids and parvicursorines are common in the formation, but ornithomimosaurs are extremely rare. A new ornithomimosaur material was discovered from the Djadokhta Formation, represented by eolian deposits, of the Tögrögiin Shiree locality, Mongolia. This is only the third ornithomimosaur specimen reported from this formation, and includes the astragalus, the calcaneum, the third distal tarsal, and a complete pes...
July 19, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28724627/using-step-width-to-compare-locomotor-biomechanics-between-extinct-non-avian-theropod-dinosaurs-and-modern-obligate-bipeds
#16
P J Bishop, C J Clemente, R E Weems, D F Graham, L P Lamas, J R Hutchinson, J Rubenson, R S Wilson, S A Hocknull, R S Barrett, D G Lloyd
How extinct, non-avian theropod dinosaurs locomoted is a subject of considerable interest, as is the manner in which it evolved on the line leading to birds. Fossil footprints provide the most direct evidence for answering these questions. In this study, step width-the mediolateral (transverse) distance between successive footfalls-was investigated with respect to speed (stride length) in non-avian theropod trackways of Late Triassic age. Comparable kinematic data were also collected for humans and 11 species of ground-dwelling birds...
July 2017: Journal of the Royal Society, Interface
https://www.readbyqxmd.com/read/28723937/electricity-system-based-on-100-renewable-energy-for-india-and-saarc
#17
Ashish Gulagi, Piyush Choudhary, Dmitrii Bogdanov, Christian Breyer
The developing region of SAARC (South Asian Association for Regional Cooperation) is home to a large number of people living below the poverty line. In future, providing affordable, universally accessible, reliable, low to zero carbon electricity in this region will be the main aim. A cost optimal 100% renewable energy system is simulated for SAARC for the year 2030 on an hourly resolved basis. The region was divided into 16 sub-regions and three different scenarios were set up based on the level of high voltage direct current (HVDC) grid connections...
2017: PloS One
https://www.readbyqxmd.com/read/28723895/visible-light-driven-methane-formation-from-co2-with-a-molecular-iron-catalyst
#18
Heng Rao, Luciana C Schmidt, Julien Bonin, Marc Robert
Converting CO2 into fuel or chemical feedstock compounds could in principle reduce fossil fuel consumption and climate-changing CO2 emissions. One strategy aims for electrochemical conversions powered by electricity from renewable sources, but photochemical approaches driven by sunlight are also conceivable. A considerable challenge in both approaches is the development of efficient and selective catalysts, ideally based on cheap and Earth-abundant elements rather than expensive precious metals. Of the molecular photo- and electrocatalysts reported, only a few catalysts are stable and selective for CO2 reduction; moreover, these catalysts produce primarily CO or HCOOH, and catalysts capable of generating even low to moderate yields of highly reduced hydrocarbons remain rare...
July 17, 2017: Nature
https://www.readbyqxmd.com/read/28722407/quantum-chemical-study-of-ch3-o2-combustion-reaction-system-catalytic-effects-of-additional-co2-molecule
#19
Artëm E Masunov, Elizabeth Wait, Subith S Vasu
The supercritical carbon dioxide diluent is used to control the temperature and to increase the efficiency in oxycombustion fossil fuel energy technology. It may affect the rates of combustion by altering mechanisms of chemical reactions, compared to the ones at low CO2 concentrations. Here, we investigate potential energy surfaces of the four elementary reactions in the CH3 + O2 reactive system in the presence of one CO2 molecule. In the case of reaction CH3 + O2 → CH2O + OH (R1 channel), van der Waals (vdW) complex formation stabilizes the transition state and reduces the activation barrier by ∼2...
July 19, 2017: Journal of Physical Chemistry. A
https://www.readbyqxmd.com/read/28721557/the-mystery-of-a-missing-bone-revealing-the-orbitosphenoid-in-basal-epicynodontia-cynodontia-therapsida-through-computed-tomography
#20
Julien Benoit, Sandra C Jasinoski, Vincent Fernandez, Fernando Abdala
The basal non-mammaliaform cynodonts from the late Permian (Lopingian) and Early Triassic are a major source of information for the understanding of the evolutionary origin of mammals. Detailed knowledge of their anatomy is critical for understanding the phylogenetic transition toward mammalness and the paleobiological reconstruction of mammalian precursors. Using micro-computed tomography (μCT), we describe the internal morphology of the interorbital region that includes the rarely fossilized orbitosphenoid elements in four basal cynodonts...
August 2017: Die Naturwissenschaften
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