keyword
MENU ▼
Read by QxMD icon Read
search

Paleo

keyword
https://www.readbyqxmd.com/read/28431380/recent-aspects-of-uranium-toxicology-in-medical-geology
#1
REVIEW
Geir Bjørklund, Olav Albert Christophersen, Salvatore Chirumbolo, Olle Selinus, Jan Aaseth
Uranium (U) is a chemo-toxic, radiotoxic and even a carcinogenic element. Due to its radioactivity, the effects of U on humans health have been extensively investigated. Prolonged U exposure may cause kidney disease and cancer. The geological distribution of U radionuclides is still a great concern for human health. Uranium in groundwater, frequently used as drinking water, and general environmental pollution with U raise concerns about the potential public health problem in several areas of Asia. The particular paleo-geological hallmark of India and other Southern Asiatic regions enhances the risk of U pollution in rural and urban communities...
April 18, 2017: Environmental Research
https://www.readbyqxmd.com/read/28431209/drug-delivery-systems-based-on-hydroxyethyl-starch
#2
Constantinos M Paleos, Zili Sideratou, Dimitris Tsiourvas
Τhe advantageous biological properties of hydroxyethyl starch (HES) triggered research interest towards design and synthesis of Drug Delivery Systems (DDSs) based on this polysaccharide. Convenient reaction schemes, including one-step reactions, led to the synthesis of HES conjugates with selected anticancer molecules or therapeutic proteins. Nanocapsules and hydrogels based on HES were also prepared and studied as prospective drug delivery systems. Formulations originating from these drug conjugates and also from nanocapsules and hydrogels loaded with drugs were characterized, highlighting on the extension of their half-life in plasma which is a critical property as far as their efficacy is concerned...
April 21, 2017: Bioconjugate Chemistry
https://www.readbyqxmd.com/read/28424397/-spatial-cognition-and-episodic-memory-formation-in-the-limbic-cortex
#3
Yasushi Kobayashi
The limbic lobe defined by Broca is a cortical region with highly diverse structure and functions, and comprises the paleo-, archi-, and neocortices as well as their transitional zones. In the limbic lobe, Brodmann designated areas 27, 28, 34, 35, and 36 adjacent to the hippocampus, and areas 23, 24, 25, 26, 29, 30, 31, 32, and 33 around the corpus callosum. In the current literature, areas 27 and 28 correspond to the presubiculum and entorhinal cortex, respectively. Area 34 represents the cortico-medial part of the amygdaloid complex...
April 2017: Brain and Nerve, Shinkei Kenkyū No Shinpo
https://www.readbyqxmd.com/read/28369914/the-%C3%AE-18-o-and-%C3%AE-2-h-of-water-in-the-leaf-growth-and-differentiation-zone-of-grasses-is-close-to-source-water-in-both-humid-and-dry-atmospheres
#4
Hai Tao Liu, Rudi Schäufele, Xiao Ying Gong, Hans Schnyder
The oxygen and hydrogen isotope composition of water in the leaf growth-and-differentiation zone, LGDZ, (δ(18) OLGDZ , δ(2) HLGDZ ) of grasses influences the isotopic composition of leaf cellulose (oxygen) and wax (hydrogen) - important for understanding (paleo)environmental and physiological information contained in these biological archives - but is presently unknown. This work determined δ(18) OLGDZ and δ(2) HLGDZ , (18) O- and (2) H-enrichment of LGDZ (∆(18) OLGDZ and ∆(2) HLGDZ ), and the (18) O- and (2) H-enrichment of leaf blade water (∆(18) OLW, ∆(2) HLW ) in two C3 and three C4 grasses grown at high and low vapor pressure deficit (VPD)...
April 3, 2017: New Phytologist
https://www.readbyqxmd.com/read/28366202/human-predatory-behavior-and-the-social-implications-of-communal-hunting-based-on-evidence-from-the-td10-2-bison-bone-bed-at-gran-dolina-atapuerca-spain
#5
Antonio Rodríguez-Hidalgo, Palmira Saladié, Andreu Ollé, Juan Luis Arsuaga, José María Bermúdez de Castro, Eudald Carbonell
Zooarcheological research is an important tool in reconstructing subsistence, as well as for inferring relevant aspects regarding social behavior in the past. The organization of hunting parties, forms of predation (number and rate of animals slaughtered), and the technology used (tactics and tools) must be taken into account in the identification and classification of hunting methods in prehistory. The archeological recognition of communal hunting reflects an interest in evolutionary terms and their inherent implications for anticipatory capacities, social complexity, and the development of cognitive tools, such as articulated language...
April 2017: Journal of Human Evolution
https://www.readbyqxmd.com/read/28281650/a-high-resolution-history-of-the-south-american-monsoon-from-last-glacial-maximum-to-the-holocene
#6
Valdir F Novello, Francisco W Cruz, Mathias Vuille, Nicolás M Stríkis, R Lawrence Edwards, Hai Cheng, Suellyn Emerick, Marcos S de Paula, Xianglei Li, Eline de S Barreto, Ivo Karmann, Roberto V Santos
The exact extent, by which the hydrologic cycle in the Neotropics was affected by external forcing during the last deglaciation, remains poorly understood. Here we present a new paleo-rainfall reconstruction based on high-resolution speleothem δ(18)O records from the core region of the South American Monsoon System (SAMS), documenting the changing hydrological conditions over tropical South America (SA), in particular during abrupt millennial-scale events. This new record provides the best-resolved and most accurately constrained geochronology of any proxy from South America for this time period, spanning from the Last Glacial Maximum (LGM) to the mid-Holocene...
March 10, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28261543/efficient-implementation-of-a-local-tomography-reconstruction-algorithm
#7
Pierre Paleo, Alessandro Mirone
We propose an efficient implementation of an interior tomography reconstruction method based on a known subregion. This method iteratively refines a reconstruction, aiming at reducing the local tomography artifacts. To cope with the ever increasing data volumes, this method is highly optimized on two aspects: firstly, the problem is reformulated to reduce the number of variables, and secondly, the operators involved in the optimization algorithms are efficiently implemented. Results show that [Formula: see text] slices can be processed in tens of seconds, while being beyond the reach of equivalent exact local tomography method...
2017: Advanced Structural and Chemical Imaging
https://www.readbyqxmd.com/read/28256409/-the-emergence-of-obstetrical-mechanism-from-lucy-to-homo-sapiens
#8
P Frémondière, L Thollon, F Marchal
The evolutionary history of modern birth mechanism is now a renewed interest in obstetrical papers. The purpose of this work is to review the literature in paleo-obstetrical field. Our analysis focuses on paleo-obstetrical hypothesis, from 1960 to the present day, based on the reconstruction of fossil pelvis. Indeed, these pelvic reconstructions usually provide an opportunity to make an obstetrical assumption in our ancestors. In this analysis, we show that modern birth mechanism takes place during the emergence of our genus 2 million years ago...
February 27, 2017: Gynecologie, Obstetrique, Fertilite & Senologie
https://www.readbyqxmd.com/read/28231621/the-biogeography-of-tropical-reef-fishes-endemism-and-provinciality-through-time
#9
Peter F Cowman, Valeriano Parravicini, Michel Kulbicki, Sergio R Floeter
The largest marine biodiversity hotspot straddles the Indian and Pacific Oceans, driven by taxa associated with tropical coral reefs. Centred on the Indo-Australian Archipelago (IAA), this biodiversity hotspot forms the 'bullseye' of a steep gradient in species richness from this centre to the periphery of the vast Indo-Pacific region. Complex patterns of endemism, wide-ranging species and assemblage differences have obscured our understanding of the genesis of this biodiversity pattern and its maintenance across two-thirds of the world's oceans...
February 23, 2017: Biological Reviews of the Cambridge Philosophical Society
https://www.readbyqxmd.com/read/28220301/evidence-that-higher-co2-increases-tree-growth-sensitivity-to-temperature-a-comparison-of-modern-and-paleo-oaks
#10
Steven L Voelker, Michael C Stambaugh, J Renée Brooks, Frederick C Meinzer, Barbara Lachenbruch, Richard P Guyette
To test tree growth sensitivity to temperature under different ambient CO2 concentrations, we determined stem radial growth rates as they relate to variation in temperature during the last deglacial period, and compare these to modern tree growth rates as they relate to spatial variation in temperature across the modern species distributional range. Paleo oaks were sampled from Northern Missouri, USA and compared to a pollen-based, high-resolution paleo temperature reconstruction from Northern Illinois, USA...
April 2017: Oecologia
https://www.readbyqxmd.com/read/28214513/molecular-dynamics-simulation-study-of-the-effect-of-glycerol-dialkyl-glycerol-tetraether-hydroxylation-on-membrane-thermostability
#11
Carme Huguet, Susanne Fietz, Antoni Rosell-Melé, Xavier Daura, Lionel Costenaro
Archaeal tetraether membrane lipids span the whole membrane width and present two C40 isoprenoid chains bound by two glycerol groups (or one glycerol and calditol). These lipids confer stability and maintain the membrane fluidity in mesophile to extremophile environments, making them very attractive for biotechnological applications. The isoprenoid lipid composition in archaeal membranes varies with temperature, which has placed these lipids in the focus of paleo-climatological studies for over a decade. Non-hydroxylated isoprenoid archaeal lipids are typically used as paleo-thermometry proxies, but recently identified hydroxylated (OH) derivatives have also been proposed as temperature proxies...
February 16, 2017: Biochimica et Biophysica Acta
https://www.readbyqxmd.com/read/28212707/astrobiological-implications-of-dim-light-phototrophy-in-deep-sea-red-clays
#12
Anindita Das, Tanya Singh, P A LokaBharathi, Prashant K Dhakephalkar, Sweta Mallik, Pranav R Kshirsagar, N H Khadge, B Nagender Nath, Satadru Bhattacharya, Aditya Kumar Dagar, Prabhjot Kaur, Dwijesh Ray, Anil D Shukla, Christabelle E G Fernandes, Sheryl O Fernandes, Tresa Remya A Thomas, Mamatha S S, Babu Shashikant Mourya, Ram Murti Meena
Red clays of Central Indian Basin (CIB) under influence of trace of Rodriguez Triple Junction exhibited chemoautotrophy, low temperature hydrothermal alterations and photoautotrophic potential. Seamount flank TVBC-08, hosting such signatures revealed dominance of aerobic anoxygenic phototroph Erythrobacter, with 93% of total 454 pyrosequencing tags. Subsequently, enrichments for both aerobic (Erythrobacter) and anaerobic anoxygenic phototrophs (green and purple sulphur bacteria) under red and white LED light illumination, with average irradiance 30...
February 2017: Life Sciences in Space Research
https://www.readbyqxmd.com/read/28192962/experimental-confirmation-of-isotope-fractionation-in-thiomolybdates-using-ion-chromatographic-separation-and-detection-by-multicollector-icpms
#13
Carolin F Kerl, Regina Lohmayer, Elvira Bura-Nakić, Derek Vance, Britta Planer-Friedrich
Molybdenum (98)Mo/(95)Mo isotope ratios are a sediment paleo proxy for the redox state of the ancient ocean. Under sulfidic conditions, no fractionation between seawater and sediment should be observed if molybdate (MoO4(2-)) is quantitatively transformed to tetrathiomolybdate (MoS4(2-)) and precipitated. However, quantum mechanical calculations previously suggested that incomplete sulfidation could be associated with substantial fractionation. To experimentally confirm isotope fractionation in thiomolybdates, a new approach for determination of isotope ratios of individual thiomolybdate species was developed that uses chromatography (HPLC-UV) to separate individual thiomolybdates, collecting each peak and analyzing isotope ratios with multicollector inductively coupled plasma mass spectrometry (MC-ICPMS)...
February 15, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28192471/the-abundance-and-diversity-of-arbuscular-mycorrhizal-fungi-are-linked-to-the-soil-chemistry-of-screes-and-to-slope-in-the-alpic-paleo-endemic-berardia-subacaulis
#14
Gabriele Casazza, Erica Lumini, Enrico Ercole, Francesco Dovana, Maria Guerrina, Annamaria Arnulfo, Luigi Minuto, Anna Fusconi, Marco Mucciarelli
Berardia subacaulis Vill. is a monospecific genus that is endemic to the South-western Alps, where it grows on alpine screes, which are extreme habitats characterized by soil disturbance and limiting growth conditions. Root colonization by arbuscular mycorrhizal fungi (AMF) is presumably of great importance in these environments, because of its positive effect on plant nutrition and stress tolerance, as well as on structuring the soil. However, there is currently a lack of information on this topic. In this paper, we tested which soil characteristics and biotic factors could contribute to determining the abundance and community composition of AMF in the roots of B...
2017: PloS One
https://www.readbyqxmd.com/read/28187385/paleo-environmental-record-of-polycyclic-aromatic-hydrocarbons-and-polychlorobiphenyls-at-the-peripheral-site-gv7-in-victoria-land-east-antarctica
#15
Stefania Giannarelli, Alessio Ceccarini, Chiara Tiribilli, Rachele Spreafico, Sandro Francesconi, Roger Fuoco
In this paper we investigated the presence of Polycyclic Aromatic Hydrocarbons and Polychlorobiphenyls in a 50-m deep snow/firn core collected at the peripheral site GV7 in East Antarctica during the 2013-2014 XXIX Italian expedition. The concentration depth profile was obtained on the basis of the total concentration of fourteen PAHs and seven PCBs individually determined by gas chromatography triple quadrupole mass spectrometry. Both classes of pollutants showed synchronized concentration vs time profile throughout the whole period of time covered by the snow/firn core (1892-2012)...
May 2017: Chemosphere
https://www.readbyqxmd.com/read/28168029/geographical-differentiation-of-the-euchiloglanis-fish-complex-teleostei-siluriformes-in-the-hengduan-mountain-region-china-phylogeographic-evidence-of-altered-drainage-patterns
#16
Yanping Li, Arne Ludwig, Zuogang Peng
The uplift of the Tibetan Plateau caused significant ecogeographical changes that had a major impact on the exchange and isolation of regional fauna and flora. Furthermore, Pleistocene glacial oscillations were linked to temporal large-scale landmass and drainage system reconfigurations near the Hengduan Mountain Region and might have facilitated speciation and promoted biodiversity in southwestern China. However, strong biotic evidence supporting this role is lacking. Here, we use the Euchiloglanis fish species complex as a model to demonstrate the compound effects of the Tibetan Plateau uplift and Pleistocene glacial oscillations on species formation in this region...
February 2017: Ecology and Evolution
https://www.readbyqxmd.com/read/28064314/-gene-pool-of-siberian-tatars-five-ways-of-origin-for-five-subethnic-groups
#17
A T Agdzhoyan, E V Balanovska, A D Padyukova, D O Dolinina, M A Kuznetsova, V V Zaporozhchenko, R A Skhalyakho, S M Koshel, M K Zhabagin, Y M Yusupov, Kh Kh Mustafin, M V Ulyanova, Z A Tychinskih, M B Lavryashina, O P Balanovsky
Siberian Tatars form the largest Turkic-speaking ethnic group in Western Siberia. The group has a complex hierarchical system of ethnographically diverse populations. Five subethnic groups of Tobol-Irtysh Siberian Tatars (N = 388 samples) have been analyzed for 50 informative Y-chromosomal SNPs. The subethnic groups have been found to be extremely genetically diverse (FST = 21%), so the Siberian Tatars form one of the strongly differentiated ethnic gene pools in Siberia and Central Asia. Every method employed in our studies indicates that different subethnic groups formed in different ways...
November 2016: Molekuliarnaia Biologiia
https://www.readbyqxmd.com/read/28009565/a-practical-local-tomography-reconstruction-algorithm-based-on-a-known-sub-region
#18
Pierre Paleo, Michel Desvignes, Alessandro Mirone
A new method to reconstruct data acquired in a local tomography setup is proposed. This method uses an initial reconstruction and refines it by correcting the low-frequency artifacts, known as the cupping effect. A basis of Gaussian functions is used to correct the initial reconstruction. The coefficients of this basis are found by optimizing iteratively a fidelity term under the constraint of a known sub-region. Using a coarse basis reduces the degrees of freedom of the problem while actually correcting the cupping effect...
January 1, 2017: Journal of Synchrotron Radiation
https://www.readbyqxmd.com/read/28008083/infidelity-in-the-outback-climate-signal-recorded-in-%C3%AE-18o-of-leaf-but-not-branch-cellulose-of-eucalypts-across-an-australian-aridity-gradient
#19
Alexander W Cheesman, Lucas A Cernusak
The isotopic composition of leaf water in terrestrial plants is highly dependent upon a plant's environment. This isotopic signature can become integrated into organic molecules, allowing the isotopic composition of biomarkers such as cellulose to be used as sensitive paleo and climatic proxies. However, the mechanisms by which cellulose isotopic composition reflect environmental conditions are complex, and may vary between leaf and woody tissues. To date few empirical tests have been made on the relative roles of leaf-water enrichment and source water on the isotopic composition of leaf and wood cellulose within the same plant...
December 21, 2016: Tree Physiology
https://www.readbyqxmd.com/read/27997756/evidence-of-molybdenum-association-with-particulate-organic-matter-under-sulfidic-conditions
#20
T W Dahl, A Chappaz, J Hoek, C J McKenzie, S Svane, D E Canfield
The geochemical behavior of molybdenum (Mo) in the oceans is closely linked to the presence of sulfide species in anoxic environments, where Fe availability may play a key role in the Mo scavenging. Here, we show that Mo(VI) is reduced in the presence of particulate organic matter (represented by sulfate-reducing bacteria). Molybdenum was immobilized at the surface of both living cells and dead/lysed cells, but not in cell-free control experiments. Experiments were carried out at four different Mo concentrations (0...
December 20, 2016: Geobiology
keyword
keyword
7570
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"