Sample records for earth history stasis
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Cell evolution and Earth history: stasis and revolution.
Cavalier-Smith, Thomas
2006-06-29
This synthesis has three main parts. The first discusses the overall tree of life and nature of the last common ancestor (cenancestor). I emphasize key steps in cellular evolution important for ordering and timing the major evolutionary innovations in the history of the biosphere, explaining especially the origins of the eukaryote cell and of bacterial flagella and cell envelope novelties. Second, I map the tree onto the fossil record and discuss dates of key events and their biogeochemical impact. Finally, I present a broad synthesis, discussing evidence for a three-phase history of life. The first phase began perhaps ca 3.5 Gyr ago, when the origin of cells and anoxic photosynthesis generated the arguably most primitive prokaryote phylum, Chlorobacteria (= Chloroflexi), the first negibacteria with cells bounded by two acyl ester phospholipid membranes. After this 'chlorobacterial age' of benthic anaerobic evolution protected from UV radiation by mineral grains, two momentous quantum evolutionary episodes of cellular innovation and microbial radiation dramatically transformed the Earth's surface: the glycobacterial revolution initiated an oxygenic 'age of cyanobacteria' and, as the ozone layer grew, the rise of plankton; immensely later, probably as recently as ca 0.9 Gyr ago, the neomuran revolution ushered in the 'age of eukaryotes', Archaebacteria (arguably the youngest bacterial phylum), and morphological complexity. Diversification of glycobacteria ca 2.8 Gyr ago, predominantly inhabiting stratified benthic mats, I suggest caused serial depletion of 13C by ribulose 1,5-bis-phosphate caboxylase/oxygenase (Rubisco) to yield ultralight late Archaean organic carbon formerly attributed to methanogenesis plus methanotrophy. The late origin of archaebacterial methanogenesis ca 720 Myr ago perhaps triggered snowball Earth episodes by slight global warming increasing weathering and reducing CO2 levels, to yield runaway cooling; the origin of anaerobic methane
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EarthN: A new Earth System Nitrogen Model
Johnson, Benjamin W.; Goldblatt, Colin
2018-01-01
The amount of nitrogen in the atmosphere, oceans, crust, and mantle have important ramifications for Earth's biologic and geologic history. Despite this importance, the history and cycling of nitrogen in the Earth system is poorly constrained over time. For example, various models and proxies contrastingly support atmospheric mass stasis, net outgassing, or net ingassing over time. In addition, the amount available to and processing of nitrogen by organisms is intricately linked with and prov...
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One hundred miles of lives: The Stasi files as a people's history of East Germany
Andrews, Molly
1998-01-01
The article explores a guiding assumption about oral history or "people's history": that it empowers "the people" simply because they are at the center of it. It provides the context of the Ministerium fur Staatsicherheit the "MfS" or "Stasi" files which were gathered by the communist government of Eastern Germany during the cold war. The author observes that although these files represent one of the most extensive examples which exist of a real people's history they are also a people's histo...
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EarthN: A new Earth System Nitrogen Model
Goldblatt, Colin; Johnson, Benjamin
2018-01-01
The amount of nitrogen in the atmosphere, oceans, crust, and mantle have important ramifications for Earth’s biologic and geologic history. Despite this importance, the history and cycling of nitrogen in the Earth system is poorly constrained over time. For example, various models and proxies contrastingly support atmospheric mass stasis, net outgassing, or net ingassing over time. In addition, the amount available to and processing of nitrogen by organisms is intricately linked with and prov...
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DEFF Research Database (Denmark)
Lange, Carsten Hjort
2017-01-01
David Armitage’s new monograph Civil Wars: A History in Ideas (2017) will undoubtedly long remain a standard reference work. It presents readers with a vision of civil war as part of the longue durée. The argument might be further strengthened, however, if a more inclusive Greco-Roman approach...... to ancient civil war is accepted. This essay focuses on stasis vs. bellum civile, the origins of the concept of civil war, the approach of later Roman writers (such as Appian and Cassius Dio) to the concepts of stasis and bellum civile, and, finally, the question of what makes a civil war a civil war....... Whatever concepts were used, the Romans were not the first to experience internal war as a civil war—that is, a war between the citizens of a polity....
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... ulcers; Ulcers - venous; Venous ulcer; Venous insufficiency - stasis dermatitis; Vein - stasis dermatitis ... veins. Some people with venous insufficiency develop stasis dermatitis. Blood pools in the veins of the lower ...
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Effects of Blood-cooling and Stasis-removing Formula on Hemorheology in Rats with Acute Blood Stasis
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Songyi Ning
2013-06-01
Full Text Available Objective: To investigate the effects of blood-cooling and stasis-removing formula on hemorheology in rats with acute blood stasis induced by mutifactor stimuli. Methods: The selected SD rats orally took blood-cooling and stasis-removing granule for six days, then the model of acute blood stasis was prepared on the fifth day by injection of epinephrine combined with ice-water bath. The variations of blood-cooling and stasis-removing granule on hemorheology were detected. Results: The high-dose group of blood-cooling and stasis-removing formula can decrease plasma viscosity in rats with acute blood stasis, and obviously reduce the blood viscosity under the condition of shear rates (200s-1, 30s-1, 5s-1, 1s-1 (P < 0.01, P < 0.05. The middle-dose group can decrease the blood viscosity under the condition of shear rate (30s-1 (P < 0.05. Conclusion: Blood-cooling and stasis-removing formula can improve abnormal hemorheology in rats with acute blood stasis.
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Korean Studies on Blood Stasis: An Overview
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Bongki Park
2015-01-01
Full Text Available Blood stasis is one of the important pathological concepts in Korean medicine. We analyzed the Korean studies concerning blood stasis. We searched for articles in eight electronic databases from their inception to September, 2014. We included reviews, clinical studies, and preclinical studies that had studied blood stasis and excluded articles in which blood stasis was not mentioned or in which the original authors had not explained blood stasis. Of 211 total included studies, 19 were reviews, 52 were clinical studies, and 140 were preclinical articles. “Stagnant blood within the body” was the most frequently mentioned phrase of the traditional concept of blood stasis. Traumatic injury was the most frequently studied disease/condition in the clinical studies. In the preclinical studies, coagulopathy was studied most frequently, followed by hyperviscosity, hyperlipidemia, inflammation, neoplasm, ischemic brain injury, and atherosclerosis. Hyeolbuchukeo-tang and Angelicae Gigantis Radix were the most frequent formula and single herb, respectively, used in the blood stasis researches. The results showed that blood stasis was mainly recognized as disorder of circulation and many studies showed the effectiveness of activating blood circulating herbs for diseases and pathologies such as traumatic injury or coagulopathy. Further studies are needed in the pathologic mechanisms and various diseases of blood stasis.
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Stasis, Charging the Space of Change
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Sarah Riviere
2017-02-01
Full Text Available This article fossicks through the fragments of historical understandings of the word stasis in ancient Greece – where stasis, in its extreme state, involved conflictual hostilities between kindred parties, often termed ‘civil war’ today. Through a series of readings of ancient Greek texts on topics ranging from pathology to literature and politics, stasis is revealed as a powerfully charged state of located dynamic exchange that operates through a precise temporal and spatial performance. This article teases out relevant aspects of the state of stasis – its high levels of spatial engagement, its inevitable resolution into energetic productivity, its precise restraint, its demand for full participation, and its role in the integration of change – all of which were acknowledged as part of the enactment and resolution of a stasis at that time. The intention of this article is to resurrect a more nuanced understanding of the state of stasis that can enrich current concepts of the dynamic in architectural and urban discourse. This understanding of stasis also poses new questions for the future design of spaces that can accommodate charged kindred engagement: lively spaces where contest becomes opportunity, and located spaces of kindred understanding that promise productive reconciliation as the common aim of all the parties involved.
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Cyclic approximation to stasis
Directory of Open Access Journals (Sweden)
Stewart D. Johnson
2009-06-01
Full Text Available Neighborhoods of points in $mathbb{R}^n$ where a positive linear combination of $C^1$ vector fields sum to zero contain, generically, cyclic trajectories that switch between the vector fields. Such points are called stasis points, and the approximating switching cycle can be chosen so that the timing of the switches exactly matches the positive linear weighting. In the case of two vector fields, the stasis points form one-dimensional $C^1$ manifolds containing nearby families of two-cycles. The generic case of two flows in $mathbb{R}^3$ can be diffeomorphed to a standard form with cubic curves as trajectories.
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[Discussion of acupuncture for diabetic peripheral neuropathy based on blood stasis theory].
Zhong, Huan; Guo, Anlin; Wang, Houlian; She, Chang; Liu, Mi; Liu, Mailan; Zhang, Wei; Chang, Xiaorong
2017-02-12
Based on the understanding of TCM and western medicine on diabetes mellitus (DM) and diabetic peripheral neuropathy (DPN), the relationship between DPN pathogenesis and blood stasis of TCM is discussed from the perspective of modern medicine. It is indicated blood stasis is the key pathogenesis to DPN, and a two-step acupuncture treatment of DPN from the theory of blood stasis is proposed. The first step is to analyze the pathogenesis of blood stasis, which could block the progress of the disease and diminish the symptoms. The second step is to apply acupuncture for pathological result of blood stasis by following the principle of eliminating exogenous pathogen , as a result, the purpose of treating both symptoms and root cause is achieved.
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van Hoeij, F B; Smout, A J P M; Bredenoord, A J
2017-08-01
After achalasia treatment, a subset of patients has poor esophageal emptying without having symptoms. There is no consensus on whether to pre-emptively treat these patients. We hypothesized that, if left untreated, these patients will experience earlier symptom recurrence than patients without stasis. 99 treated achalasia patients who were in clinical remission (Eckardt ≤3) at 3 months after treatment were divided into two groups, based on presence or absence of esophageal stasis on a timed barium esophagogram performed after 3 months. Two years after initial treatment, patients with stasis after treatment still had a wider esophagus (3 cm; IQR: 2.2-3.8) and more stasis (3.5 cm; IQR: 1.9-5.6) than patients without stasis (1.8 cm wide and 0 cm stasis; both Ptreatment also had a higher degree of stasis and a more dilated esophagus, compared to patients without stasis, they did not have a higher chance of requiring retreatment. We conclude that stasis in symptom-free achalasia patients after treatment does not predict treatment failure within 2 years and can therefore not serve as a sole reason for retreatment. © 2017 John Wiley & Sons Ltd.
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International Nuclear Information System (INIS)
Allegre, C.
1997-01-01
Isotopic dating is the principal technique that enabled researches on the Earth history, its origins and formation: planets were formed by accretion, and the study of meteorites allowed to confirm that the accretion was of the homogenous type; the study of meteorites allowed also to determine the solar system formation, while the mantel rocks dating gave an estimation of the Earth age (and the Moon), and the gas confined in eruptive submarine rocks gave insights on the atmosphere formation
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Radiological evaluation of the chronic venous stasis syndrome
International Nuclear Information System (INIS)
Train, J.S.; Schanzer, H.; Peirce, E.C. II; Dan, S.J.; Mitty, H.A.
1987-01-01
Chronic venous stasis is an extremely complex clinical syndrome of pain and changes in the skin that can involve the superficial, deep, and perforating veins. This syndrome is commonly referred to as the postphlebitic syndrome, implying that thrombophlebitis is its sole etiology. To test this hypothesis, the authors performed ascending venography on 51 limbs of patients with the chromic venous stasis syndrome and demonstrated that 32 had no radiological evidence of recent or old thrombophlebitis. Instead, they had normal-appearing veins, suggesting primary incompetence of the deep and/or perforating venous valves rather than thrombophlebitis as the etiology. Since various operations have recently been proposed to correct or bypass malfunctioning valves, precise demonstration of pathological change is required to choose the appropriate procedure and to evaluate results. Descending venograms were combined with the ascending studies in 42 limbs for this purpose. In addition to outlining the abnormalities responsible for chronic venous stasis syndrome in individual cases, interesting conclusions regarding the syndrome itself were reached
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Volatile accretion history of the Earth.
Wood, B J; Halliday, A N; Rehkämper, M
2010-10-28
It has long been thought that the Earth had a protracted and complex history of volatile accretion and loss. Albarède paints a different picture, proposing that the Earth first formed as a dry planet which, like the Moon, was devoid of volatile constituents. He suggests that the Earth's complement of volatile elements was only established later, by the addition of a small veneer of volatile-rich material at ∼100 Myr (here and elsewhere, ages are relative to the origin of the Solar System). Here we argue that the Earth's mass balance of moderately volatile elements is inconsistent with Albarède's hypothesis but is well explained by the standard model of accretion from partially volatile-depleted material, accompanied by core formation.
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The first 800 million years of earth's history
Smith, J. V.
1981-01-01
It is pointed out that there is no direct geological information on the first 750 Ma of earth history. Consequently the reported study is based on controversial inferences drawn from the moon, other planets and meteorites, coupled with backward extrapolation from surviving terrestrial rocks, especially those of Archaean age. Aspects of accretion are considered, taking into account cosmochemical and cosmophysical evidence, a new earth model, and convection systems. Attention is given to phase-equilibrium constraints, estimates of heat production, the bombardment history of the moon and implications for the earth, and the nature of the early crust. From a combination of physical, chemical, and petrological arguments, it is concluded that the earth's surface underwent intense volcanism in the pre-Archaean era, and that the rock types were chemically similar to those found in the early Archaean era.
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Transformation Stasis Phenomenon of Bainite Formation in Low-Carbon, Multicomponent Alloyed Steel
Lan, Liangyun; Kong, Xiangwei
2017-11-01
The transformation stasis phenomenon of bainite formation in low-carbon steel was detected using a high-resolution dilatometer. The phenomenon occurred at different stages for different isothermal temperatures. In combination with microstructural observation, the calculated overall activation energy of transformation and interface migration velocity shed new light on the cause of formation of the stasis phenomenon. The temporary stasis formed at the initial stage of phase transformation for high isothermal temperature was attributed to the drag effect of substitutional atoms, which leads to low-interface migration velocity and large overall activation energy.
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Intelligent Design and Earth History
Elders, W. A.
2001-05-01
clumsy, wasteful works of nature as seen in the suffering caused by parasites and in the delight in cruelty shown by some predators when catching and playing with their prey". The positions of other contemporary proponents of ID are far from uniform. Some, while rejecting unguided evolution, appear to accept the concepts of common descent and an Earth 4.6 billion years old. However, within the ID movement there has been very little discussion of its implications for Earth history. For example, is it valid to ask, "Were the Himalayas intelligently designed?" Or should the question be, "Is the physics of plate tectonics intelligently designed?" As well as contingency in the history of life, there are strong elements of contingency in the history of the Earth, in the history of the solar system and in the history of the cosmos. Does ID matter? From a purely operational viewpoint, the rock record could equally well be interpreted in pattern-based investigations as being the product of either naturalistic processes, or as a sequence of intelligently designed events. For example, in correlating horizons between adjacent oil wells using micropaleontology, or in doing seismic stratigraphy, it makes little difference whether foraminifera or unconformities formed by natural or supernatural agencies. However, ID is an anathema for process-based research and its cultural implications are enormous. While we must be careful in our work to separate methodological naturalism from culturally bound philosophical naturalism, methodological naturalism has been an enormously successful approach in the advancement of knowledge. We have moved from the "demon-haunted" world to the world of the human genome. We must take ID seriously; it is a retrograde step.
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Berger, W. H.; Crowell, J. C.
1982-01-01
Complex atmosphere-ocean-land interactions govern the climate system and its variations. During the course of Earth history, nature has performed a large number of experiments involving climatic change; the geologic record contains much information regarding these experiments. This information should result in an increased understanding of the climate system, including climatic stability and factors that perturb climate. In addition, the paleoclimatic record has been demonstrated to be useful in interpreting the origin of important resources-petroleum, natural gas, coal, phosphate deposits, and many others.
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Hao, Er-Wei; Deng, Jia-Gang; Du, Zheng-Cai; Yan, Ke; Zheng, Zuo-Wen; Wang, Qin; Huang, Li-Zhen; Bao, Chuan-Hong; Deng, Xiu-Qiong; Lu, Xiao-Yan; Tang, Zhi-Ling
2012-11-01
To study the action characteristics of "two-way application and conditioned dominance" of traditional Chinese medicines with neutral property by observing the action characteristic of 10 traditional Chinese medicines capable of promoting blood circulation and removing blood stasis with neutral property in the microcirculation in rats with heat stagnation and blood stasis syndrome. The rat model with heat stagnation and blood stasis syndrome was established by injecting carrageenan and dry yeast, and the rat model with cold stagnation and blood stasis syndrome was built by the body freezing method. Ten traditional Chinese medicines with neutral property, including 5 with hot property and 5 with cold property, were selected for intervention to observe blood flow rate and flow state indicators in rat auricles and make a comparative analysis on action characteristics of traditional Chinese medicines with neutral property. ANOVA showed that among the 10 traditional Chinese medicines with neutral property, 6 such as Typhae Pollen, Sappan Lignum and Vaccariae Semen can obviously increase the blood flow rate (P traditional Chinese medicines with cold property can increase the blood flow rate (P medicines showed no notable effect; among the 5 traditional Chinese medicines with hot property, Carthamus tinctorius and Ligusticum chuanxiong can increase the blood flow rate (P traditional Chinese medicines with natural and cold properties showed similar effect on heat stagnation and blood stasis syndrome and better effect in increasing blood flow rate than those with hot property; those with natural and hot properties showed similar effect and better effect in increasing blood flow rate than those with cold property. Under the condition of heat stagnation and blood stasis syndrome, traditional Chinese medicines with neutral property have the similar action characteristics with those with cold property; wile under the condition of cold stagnation and blood stasis syndrome
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Ruthford, Steven; DeBari, Susan; Linneman, Scott; Boriss, Miguel; Chesbrough, John; Holmes, Randall; Thibault, Allison
2013-04-01
Beginning in 2003, faculty from Western Washington University, Skagit Valley Community College, local public school teachers, and area tribal college members created an innovative, inquiry based undergraduate geology curriculum. The curriculum, titled "Energy and Matter in Earth's Systems," was supported through various grants and partnerships, including Math and Science Partnership and Noyce Teacher Scholarship grants from the National Science Foundation. During 2011, the authors wrote a geologic time unit for the curriculum. The unit is titled, "How Do We Know About Earth's History?" and has students actively investigate the concepts related to geologic time and methods for determining age. Starting with reflection and assessment of personal misconceptions called "Initial Ideas," students organize a series of events into a timeline. The unit then focuses on the concepts of relative dating, biostratigraphy, and historical attempts at absolute dating, including uniformitarianism, catastrophism, Halley and Joly's Salinity hypothesis, and Kelvin's Heat Loss model. With limited lecture and text, students then dive into current understandings of the age of the Earth, which include radioactive decay rates and radiometric dating. Finally, using their newfound understanding, students investigate a number of real world scenarios and create a timeline of events related to the geologic history of the Earth. The unit concludes with activities that reinforce the Earth's absolute age and direct students to summarize what they have learned by reorganizing the timeline from the "Initial Ideas" and sharing with the class. This presentation will include the lesson materials and findings from one activity titled, "The Earth's Story." The activity is located midway through the unit and begins with reflection on the question, "What are the major events in the Earth's history and when did they happen?" Students are directed to revisit the timeline of events from the "Initial Ideas
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Toju, Hirokazu; Sota, Teiji
2009-09-01
One of the major controversies in evolutionary biology concerns the processes underlying macroevolutionary patterns in which prolonged stasis is disrupted by rapid, short-term evolution that leads species to new adaptive zones. Recent advances in the understanding of contemporary evolution have suggested that such rapid evolution can occur in the wild as a result of environmental changes. Here, we examined a novel hypothesis that evolutionary stasis is punctuated by co-evolutionary arms races, which continuously alter adaptive peaks and landscapes. Based on the phylogeny of long-mouthed weevils in the genus Curculio, likelihood ratio tests showed that the macroevolutionary pattern of the weevils coincides with the punctuational evolution model. A coalescent analysis of a species, Curculio camelliae, the mouthpart of which has diverged considerably among populations because of an arms race with its host plant, further suggested that major evolutionary shifts had occurred within 7000 generations. Through a microevolutionary analysis of the species, we also found that natural selection acting through co-evolutionary interactions is potentially strong enough to drive rapid evolutionary shifts between adaptive zones. Overall, we posit that co-evolution is an important factor driving the history of organismal evolution.
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Controllori controllati: le finestre della Stasi
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Alessandra Goggio
2015-01-01
Full Text Available This short essay aims to investigate the role played by the object ‘window’ in different post-1989 German representations of the so-called Stasi, that is to say, the secret policy of the German Democratic Republic. In particular, we will linger our attention on a precise situation, that of the controlled-controller, which often recurs in such representations. By analysing three different artistic products (one film: The life of the others by Florian Henckel von Donnersmarck, and two novels: Ich by Wolfgang Hilbig and Helden wie wir by Thomas Brussig we will attempt to show how windows largely contributed not only to the functioning of the Stasi itself, but also to creating a country full of spies spying on one another without even knowing of being controlled by others. In the end we will demonstrate how the use of windows in this particular kind of representation also alludes to the concept of the Panopticon (Jeremy Bentham and its theoretical application carried out by the French philosopher Michael Foucault.
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Mineral evolution and Earth history
Bradley, Dwight C.
2015-01-01
The field of mineral evolution—a merger of mineralogy and Earth history—coalesced in 2008 with the first of several global syntheses by Robert Hazen and coworkers in the American Mineralogist. They showed that the cumulative abundance of mineral species has a stepwise trend with first appearances tied to various transitions in Earth history such as the end of planetary accretion at ca. 4.55 Ga and the onset of bio-mediated mineralogy at ca. >2.5 Ga. A global age distribution is best established for zircon. Observed abundance of zircon fluctuates through more than an order of magnitude during successive supercontinent cycles. The pulse of the Earth is also recorded, albeit imperfectly, by the 87Sr/86Sr composition of marine biogenic calcite; the Sr-isotopic ratio of this mineral reflects the balance of inputs of primitive strontium at mid-ocean ridges and evolved strontium that drains off the continents. A global mineral evolution database, currently in the works, will greatly facilitate the compilation and analysis of extant data and the expansion of research in mineralogy outside its traditional bounds and into more interdisciplinary realms.
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Li, Wei-wei; Guo, Hao; Wang, Xue-mei
2013-09-01
"Qi" and "blood" are two essential concepts in Chinese medicine (CM). As qi is intangible, the concept of qi is still controversial between CM and Western medicine. However, the endogenous hydrogen sulfide (H2S) and other gaseous signaling molecules provides a new approach for understanding the essence of qi in CM. Blood stasis syndrome is a common syndrome in CM. According to the CM theory, the incidence of blood stasis syndrome is closely correlated to the reckless movement of qi, as qi and blood are inseparable in regulating physiological functions. In recent years, more and more evidences suggest a close correlation between blood stasis syndrome and microcirculation dysfunction. In this paper, we discuss the relationship between endogenous H2S and blood stasis syndrome based on qi-blood theory of CM. We found that endogenous H2S maybe a material basis in concept of qi in CM, while dysfunctional microcirculation is the pathological basis of the blood stasis syndrome. As qi is closely associated with incidence and progression of blood stasis syndrome, endogenous H2S may play an important role in preventing and treating the blood stasis syndrome by improving the function of microcirculation.
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METÁSTASIS CEREBRALES: UNA MIRADA BIOLÓGICA Y CLÍNICA
Dr. Arnaldo Marín; Dr. Alex Renner; Dra. Laura Itriago; Dr. Manuel Álvarez
2017-01-01
Las metástasis cerebrales son los tumores cerebrales más frecuentes y son un desafío médico. Los tumores tienen una capacidad diferente de metastatizarse en el cerebro y deben tener la capacidad de penetrar la barrera hematoencefálica, interactuar con las células residentes y sobrevivir. La clínica es variada dependiendo del sitio afectado, así como los riesgos asociados de convulsión. Genómicamente se ha documentado cada vez más que las metástasis cerebrales cambian la expresión de sus mu...
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Criticality analyses of regions containing uranium in the earth history
International Nuclear Information System (INIS)
Ravnik, M.
2005-01-01
Investigations of necessary conditions for a self-sustained chain reaction in the Earth inner regions hypothetically containing uranium is presented for the time interval from Earth formation to present time. It is determined that criticality was theoretically possible up to 2.5 Ga before present if uranium concentrated in pure form. In the early geological history (4 Ga before present) the self-sustained criticality could occur even if uranium was diluted up to 1:20 by the average core material or 1:60 by the average mantle material. If other metallic materials of similar density as uranium (e.g., Au, W) or similar atomic weight (e.g., Th) concentrated from the primordial mixture in equal proportion as uranium, criticality was not possible for any period in Earth history provided that the basic material contained no light nuclides (H, C). Criticality in the Earth inner regions could have established only if uranium concentrated from the basic material more effectively than elements of similar density or atomic number. (orig.)
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Google earth as a source of ancillary material in a history of psychology class.
Stevison, Blake K; Biggs, Patrick T; Abramson, Charles I
2010-06-01
This article discusses the use of Google Earth to visit significant geographical locations associated with events in the history of psychology. The process of opening files, viewing content, adding placemarks, and saving customized virtual tours on Google Earth are explained. Suggestions for incorporating Google Earth into a history of psychology course are also described.
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Directory of Open Access Journals (Sweden)
Ying Wang
2017-06-01
Full Text Available Invigorating blood and dissolving stasis method is a kind of unique therapy of Traditional Chinese Medicine(TCMtreatment, which efficacy has become increasingly prominent in the treatment of ophthalmology. With the further studies of blood stasis and invigorating blood and dissolving stasis therapy, it is widely used in clinical ophthalmology, and get good effects beyond thought, especially when western medicine has no curative effects. It improved the cure rate of fundus oculi disease from the eyelids, conjunctiva, lacrimal sac, vitreous body to the choroid and retina, optic nerve and macula lutea, from surface to fundus, or pathological changes related to inflammation, degeneration, necrosis, atrophy, hyperplasia of fibrous tissue hyperplasia. This paper is aim to explain the definition of invigorating blood and dissolving stasis and make a review of basic research and clinical application about it in several diseases.
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Sun-Earth Day Connects History, Culture and Science
Cline, T.; Thieman, J.
2003-12-01
The NASA Sun-Earth Connection Education forum annually promotes and event called Sun-Earth Day: a national celebration of the Sun, the space around the Earth (geospace), and how all of it affects life on our planet. For the past 3 years this event has provided a venue by which classrooms, museums, planetaria, and at NASA centers have had a sensational time sharing stories, images, and activities related to the Sun-Earth connections and the views o fthe Sun from Earth. Each year we select a different theme by which NASA Space Science can be further related to cross-curricular activities. Sun-Earth Day 2002, "Celebrate the Equinox", drew parallels between Native American Cultures and NASA's Sun-Earth Connection research via cultural stories, interviews, web links, activities and Native American participation. Sun-Earth Day 2003, "Live From the Aurora", shared the beauty of the Aurora through a variety of activities and stories related to perspectives of Northern Peoples. Sun-Earth Day 2004 will share the excitement of the transit of Venus through comparisons of Venus with Earth and Mars, calculations of the distances to nearby stars, and the use of transits to identify extra-solar planets. Finally, Sun-Earth Day 2005 will bring several of these themes together by turning our focus to the history and culture surrounding ancient observatories such as Chaco Canyon, Machu Picchu, and Chichen Itza.
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Wang, Hai-Yan; Jiang, Liang-Duo; Ma, Qing; Xu, Dong; Tang, Shi-Huan; Luo, Zeng-Gang
2017-12-01
In the clinical practice, Professor Jiang Liangduo, a national senior Chinese medicine doctor, has created the theory of "sanjiao meridian stasis" from the theory of meridian dialectics and from the overall state. In this paper, the traditional Chinese medicine and Western medicine clinical characteristics of sanjiao meridian stasis theory which is often used by Professor Jiang Liangduo in the treatment of out-patient syndrome differentiation, were first studied and summarized to investigate its inherent regularity. First, the source of data and research methods were introduced, and then the Traditional Chinese Medicine Inheritance Support System was used with the method of data mining to retrospectively analyze the disease characteristics of Chinese and Western medicine in 279 patients with sanjiao meridian stasis diagnosed by Professor Jiang in 2014. Then the following main conclusions were made after research: sanjiao meridian stasis was more common in women as well as young and middle-aged population. Often manifested by prolonged treatment course, red tongue with yellowishfur, with good correlation between modern Western medicine diagnosis and TCM differentiation syndrome. The symptoms of sanjiao meridian stasis syndrome are mostly of heat syndromes, and middle-aged patients are the most common patients with stasis and stasis of sanjiao. Related information of Western medicine diagnosis can help to diagnose the "sanjiao meridian stasis". Copyright© by the Chinese Pharmaceutical Association.
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METÁSTASIS CEREBRALES: UNA MIRADA BIOLÓGICA Y CLÍNICA
Directory of Open Access Journals (Sweden)
Dr. Arnaldo Marín
2017-05-01
Por lo tanto, la elección del tratamiento es compleja, considerando la primaria, el número de metástasis y los sitios afectados. La radioterapia ha sido durante mucho tiempo la elección de los pacientes que no son candidatos a la cirugía, y se espera que los avances reduzcan especialmente la toxicidad cognitiva. El conocimiento genómico de las metástasis cerebrales y la presencia de terapias dirigidas e inmunoterapias modificadas que penetran la barrera hematoencefálica han sido clave, se espera que en el futuro se realicen más estudios de combinaciones de tratamientos de radioterapia con terapias de inmunoterapia y dirigidas.
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Counteracting venous stasis during acute lower leg immobilization.
Poelkens, F.; Thijssen, D.H.J.; Kersten, B.T.P.; Scheurwater, H.; Laarhoven, E.W. van; Hopman, M.T.E.
2006-01-01
AIM: During lower limb immobilization, patients are at risk to develop deep venous thrombosis. Recently, a water-pad was developed that should counteract venous stasis. The water-pad, located under the plaster, mobilizes water from the foot to the calf during weight bearing and, thereby, imitates
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Ma, Cai-Yun; Liu, Jing-Hua; Liu, Jian-Xun; Shi, Da-Zhuo; Xu, Zhen-Ye; Wang, Shao-Ping; Jia, Min; Zhao, Fu-Hai; Jiang, Yue-Rong; Ma, Qin; Peng, Hong-Yu; Lu, Yuan; Zheng, Ze; Ren, Feng-Xue
2017-11-01
To investigate the relationship between inflammatory factors and two Chinese medicine (CM) syndrome types of qi stagnation and blood stasis (QSBS) and qi deficiency and blood stasis (QDBS) in patients with acute coronary syndrome (ACS). Sixty subjects with ACS, whose pathogenesis changes belongs to qi disturbance blood stasis syndrome, were divided into 2 groups: 30 in the QSBS group and 30 in the QDBS group. The comparative analysis on them was carried out through comparing general information, coronary angiography and inflammatory factors including intracellular adhesion molecule-1 (ICAM-1), chitinase-3-like protein 1 (YKL-40) and lipoprotein-associated phospholipase A2 (Lp-PLA2). Compared with the QSBS group, Lp-PLA2 and YKL-40 levels in the QDBS group showed no-significant difference (P>0.05); ICAM-1 was significantly higher in the QDBS group than in the QSBS group in the pathological processes of qi disturbance and blood stasis syndrome of ACS (Psyndrome typing of QSBS and QDBS, which provides a research direction for standardization research of CM syndrome types.
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Effect of Qingnao tablet on blood viscosity of rat model of blood stasis induced by epinephrine
Xie, Guoqi; Hao, Shaojun; Ma, Zhenzhen; Liu, Xiaobin; Li, Jun; Li, Wenjun; Zhang, Zhengchen
2018-04-01
To establish a rat model of blood stasis with adrenaline (Adr) subcutaneous injection and ice bath stimulation. The effects of different doses on the blood viscosity of blood stasis model rats were observed. The rats were randomly divided into 6 groups: blank control group (no model), model group, positive control group, high, middle and low dose group. The whole blood viscosity and plasma viscosity were detected by blood viscosity instrument. Compared with the blank group, model group, high shear, low shear whole blood viscosity and plasma viscosity were significantly increased, TT PT significantly shortened, APTT was significantly prolonged, FIB increased significantly, indicating that the model was successful. Compared with the model group, can significantly reduce the Naoluotong group (cut, low cut). Qingnaopian high dose group (low cut), middle dose group (cut, low shear blood viscosity) (Pgroup, high dose group (Pgroup (Pblood rheology of blood stasis mice abnormal index, decrease the blood viscosity, blood stasis has certain hemostatic effect.
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New Developments Regarding the KT Event and Other Catastrophes in Earth History
1994-01-01
Papers presented at the conference on New Developments Regarding the KT Event and Other Catastrophes in Earth History are included. Topics covered include: trajectories of ballistic impact ejecta on a rotating earth; axial focusing of impact energy in the earth's interior: proof-of-principle tests of a new hypothesis; in search of Nemesis; impact, extinctions, volcanism, glaciations, and tectonics: matches and mismatches.
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International Nuclear Information System (INIS)
Qu Shaochun; Yu Xiaofeng; Wang Jia; Zhou Jinying; Xie Haolin; Sui Dayun
2010-01-01
Objective: To construct the acute myocardial infarction models in rats with blood stasis and study the difference on blood biochemics between the acute myocardial infarction models with blood stasis and the simple acute myocardial infarction models. Methods: Wistar rats were randomly divided into control group, acute blood stasis model group, acute myocardial infarction sham operation group, acute myocardial infarction model group and of acute myocardial infarction model with blood stasis group. The acute myocardial infarction models under the status of the acute blood stasis in rats were set up. The serum malondialdehyde (MDA), nitric oxide (NO), free fatty acid (FFA), tumor necrosis factor-α (TNF-α) levels were detected, the activities of serum superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and the levels of prostacycline (PGI2), thromboxane A 2 (TXA 2 ) and endothelin (ET) in plasma were determined. Results: There were not obvious differences in MDA, SOD, GSH-Px and FFA between the acute myocardial infarction models with blood stasis in rats and the simple acute myocardial infarction models (P 2 and NO, and the increase extents of TXA 2 , ET and TNF-α in the acute myocardial infarction models in rats with blood stasis were higher than those in the simple acute myocardial infarction models (P 2 and NO, are significant when the acute myocardial infarction models in rats with blood stasis and the simple acute myocardial infarction models are compared. The results show that it is defective to evaluate pharmacodynamics of traditional Chinese drug with only simple acute myocardial infarction models. (authors)
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Neumotórax bilateral como complicación de metástasis pulmonar cavitaria de un angiosarcoma
Directory of Open Access Journals (Sweden)
Lorena V. Maldonado
2014-06-01
Full Text Available Las metástasis pulmonares de angiosarcoma constituyen una complicación común de una neoplasia maligna poco frecuente. Habitualmente se presentan como nódulos solidos periféricos y derrame pleural. Presentamos el caso de un hombre de 65 años de edad con neumotórax bilateral recurrente, secundario a metástasis cavitadas de un angiosarcoma primitivo de cuero cabelludo. La videotoracoscopia permitió la inspección, la resección de las metástasis y la pleurodesis. No ocurrieron complicaciones ni recurrencia tumoral a los seis meses de seguimiento.
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Revolutions in energy input and material cycling in Earth history and human history
Lenton, Timothy M.; Pichler, Peter-Paul; Weisz, Helga
2016-04-01
Major revolutions in energy capture have occurred in both Earth and human history, with each transition resulting in higher energy input, altered material cycles and major consequences for the internal organization of the respective systems. In Earth history, we identify the origin of anoxygenic photosynthesis, the origin of oxygenic photosynthesis, and land colonization by eukaryotic photosynthesizers as step changes in free energy input to the biosphere. In human history we focus on the Palaeolithic use of fire, the Neolithic revolution to farming, and the Industrial revolution as step changes in free energy input to human societies. In each case we try to quantify the resulting increase in energy input, and discuss the consequences for material cycling and for biological and social organization. For most of human history, energy use by humans was but a tiny fraction of the overall energy input to the biosphere, as would be expected for any heterotrophic species. However, the industrial revolution gave humans the capacity to push energy inputs towards planetary scales and by the end of the 20th century human energy use had reached a magnitude comparable to the biosphere. By distinguishing world regions and income brackets we show the unequal distribution in energy and material use among contemporary humans. Looking ahead, a prospective sustainability revolution will require scaling up new renewable and decarbonized energy technologies and the development of much more efficient material recycling systems - thus creating a more autotrophic social metabolism. Such a transition must also anticipate a level of social organization that can implement the changes in energy input and material cycling without losing the large achievements in standard of living and individual liberation associated with industrial societies.
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International Nuclear Information System (INIS)
Davies, G.F.
1980-01-01
Thermal histories have been calculated for simple models of the earth which assume that heat is transported by convection throughout the interior. The application of independent constraints to these solutions limits the acceptable range of the ratio of present radiogenic heat production in the earth to the present surface heat flux. The models use an empirical relation between the rate of convective heat transport and the temperature difference across a convecting fluid. This is combined with an approximate proportionality between effective mantle viscosity and T/sup -n/, where T is temperature and it is argued that n is about 30 throughout the mantle. The large value of n causes T to be strongly buffered against changes in the earth's energy budget and shortens by an order of magnitude the response time of surface heat flux to changes in energy budget as compared to less temperature-dependent heat transport mechanisms. Nevertheless, response times with n=30 are still as long as 1 or 2 b.y. Assuming that the present heat flux is entirely primordial (i.e., nonradiogenic) in a convective model leads back to unrealistically high temperatures about 1.7 b.y. ago. Inclusion of exponentially decaying (i.e., radiogenic) heat sources moves the high temperatures further into the past and leads to a transition from 'hot' to 'cool' calculated thermal histories for the case when the present rate of heat production is near 50% of the present rate of heat loss. Requiring the calculated histories to satisfy minimal geological constraints limits the present heat production/heat loss ratio to between about 0.3 and 0.85. Plausible stronger constraints narrow this range to between 0.45 and 0.65. These results are compatible with estimated radiogentic heat production rates in some meteorites and terrestrial rocks, with a whole-earth K/U ratio of 1--2 x 10 4 giving optimal agreement
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DEFF Research Database (Denmark)
Bülow, J; Henriksen, O; Amtorp, Ole
1984-01-01
venous stasis. In another experimental series the effect of general pentobarbital anesthesia on the vasoconstrictor activity in response to venous stasis locally in subcutaneous and muscle tissue in the hind limb was examined in 6 dogs. It was found that during the first 2-3 h of anesthesia...... the vasoconstrictor response was present in both tissues although the response in muscle tissue exhibited a great variation between the dogs during this period. However, after 4-5 h of anesthesia the response was abolished in both tissues. During neurolept anesthesia with fentanyl/N2O the same vasoconstrictor...... response was demonstrated in the hindleg 1 h and 5 h after induction of the anesthesia. It is concluded that pentobarbital anesthesia abolishes the arteriolar constriction induced by venous stasis. The mechanism may be blockade of the local sympathetic vasoconstrictor fibres or interference with myogenic...
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Between History and Apocalypse: Stumbling
Lalu, Premesh
2016-01-01
Apartheid rested on a division of the senses as much as it did on a reductive politics of racial subjection and its accompanying violence. As an instance of the division of the senses, it produced a condition of stasis in which history and a post-apartheid future were increasingly marked by a politico-religious discourse of apocalypse, and a moral…
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Eyuboglu, Atilla Adnan; Uysal, Cagri A; Ozgun, Gonca; Coskun, Erhan; Markal Ertas, Nilgun; Haberal, Mehmet
2018-03-01
Stasis zone is the surrounding area of the coagulation zone which is an important part determining the extent of the necrosis in burn patients. In our study we aim to salvage the stasis zone by injecting adipose derived stromal vascular fraction (ADSVF). Thermal injury was applied on dorsum of Sprague-Dawley rats (n=20) by the "comb burn" model as described previously. When the burn injury was established on Sprague-Dawley rats (30min); rat dorsum was separated into 2 equal parts consisting of 4 burn zones (3 stasis zone) on each pair. ADSVF cells harvested from inguinal fat pads of Sprague-Dawley rats (n=5) were injected on the right side while same amount of phosphate buffered saline (PBS) injected on the left side of the same animal. One week later, average vital tissue on the statis zone was determined by macroscopy, angiography and microscopy. Vascular density, inflammatory cell density, gradient of fibrosis and epithelial thickness were determined via immunohistochemical assay. Macroscopic stasis zone tissue viability (32±3.28%, 57±4.28%) (p51, 1.50±0.43) (pzone on acute burn injuries. Copyright © 2017 Elsevier Ltd and ISBI. All rights reserved.
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Ionizing radiations in the natural history of the Earth: role of supernova flares
International Nuclear Information System (INIS)
Byakov, V.M.
1996-01-01
Paper discusses the role of supernova flares in the natural history of the Earth. Probability of the solar system occurrence in the residual of supernova explosion is estimated Possible effects of the Earth occurrence in the supernova residual are studied. 29 refs., 3 tabs
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Metástasis en hueso maxilar superior de adenocarcinoma de esófago: presentación de un caso clínico
Sánchez Jiménez, Juan; Acebal Blanco, Faustino; Arévalo Arévalo, Rafael; Molina Martínez, Manuel
2005-01-01
Las metástasis en cavidad oral son lesiones raras que representan aproximadamente el 1% de todas las neoplasias malignas de cavidad oral. Las metástasis orales se localizan en un 80-90% en mandíbula, siendo mas raras en maxilar superior. Las metástasis en tejidos blandos de boca son raras, y es encía donde con mayor frecuencia se localizan las metástasis en tejidos blandos en boca. Los tumores primarios que metastatizan a boca son los más frecuentes pulmón, mama y riñón. ...
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Metástasis hipofisaria Hypophyseal metastasis
Directory of Open Access Journals (Sweden)
Miguel Ángel Yanes Quesada
2009-04-01
Full Text Available mayoría son lesiones silentes descubiertas accidentalmente en las autopsia. La aparición de metástasis sintomáticas es, en cambio, excepcional. DESARROLLO: se describen aquí los hallazgos clínicos y radiológicos de una paciente femenina de 69 años, con un carcinoma indiferenciado del pulmón, diagnosticado hace 2 años y medio, que comenzó con cefalea y trastornos visuales sin hipopituitarismo ni diabetes insípida. Se le realizó resonancia magnética nuclear y se le diagnosticó una lesión hipofisaria, que fue operada por vía tranesfenoidal, y se informó por anatomía patológica una metástasis del carcinoma del pulmón. CONCLUSIONES: la paciente se encuentra en estos momentos recibiendo quimioterapia, radioterapia y anticuerpo monoclonal con evolución favorable.INTRODUCTION: metastatic tumors of hypophyseal gland are infrequent. Most are silent lesions discovered accidentally in necropsy. Appearance of symptomatic metastasis is however, exceptional. DEVELOPMENT: we describe here clinical and radiological findings in a female patient aged 69, presenting with a non-differential carcinoma of lung, diagnosed two years a half ago, starting with headache and visual disorders without hypopituitarism and insipidus diabetes. We made a nuclear magnetic resonance and diagnosis was a hypophyseal lesion operated on by trans-esphenoidal route, and Pathological Anatomy Service reports a metastasis of lung carcinoma. CONCLUSIONS: patient receives chemotherapy, radiotherapy, and monoclonal antibody with a favorable evolution.
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Qiu, Xin; Wang, Kai-xin; Chen, Guo-hua
2011-11-01
To analyze the correlation between risk factors and ischemic cerebral stroke of wind-phlegm collateral obstruction syndrome and qi deficiency blood stasis syndrome. Totally 900 patients of the two syndrome types were recruited. Risk factors correlated to ischemic cerebral stroke such as gender, age, time of onset, site of infarction, tongue proper, tongue fur, pulse picture, hypertension, diabetes, past stroke history, hyperlipidemia, hematocrit, smoking, drinking, genetic factor, blood type, complications were analyzed using Chi-square test and non-conditional Logistic regression analysis. Statistical significance existed between the two syndrome types in age (X2 = 8.2392, P = 0.0413), hyperlipidemia (X2 = 4.8386, P = 0.0278), tongue proper (X2 = 7.9470, P = 0.0048), and tongue fur (X2 = 4.3298, P = 0.0375). Statistical significance existed between the two syndrome types in hyperlipidemia, tongue proper, and tongue fur, and their OR value was 0.699 (P = 0.0282), 0.332 (P =0.0071), and 0.667 (P = 0.0382) respectively. The OR value of the past stroke history was 3.226 (P = 0.0314), that of complications 0.203 (P = 0.0705), and that of anterior circulation infarction 0.214 (P = 0.0098). Among different ages groups, the constituent ratio of qi deficiency blood stasis syndrome was obviously higher than that of wind-phlegm collateral obstruction syndrome. Besides, patients of qi deficiency blood stasis syndrome were liable to suffer from hyperlipidemia, anterior circulation infarction, and complications. The age, blood lipid levels, site of infarction, complications are closely correlated with Chinese syndrome types of ischemic cerebral stroke, which can provide objective indices for typing ischemic cerebral stroke.
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Wang, Feng-Qin; Chen, Cen; Xia, Zhi-Ning; Yang, Feng-Qing
2014-08-01
Thrombotic diseases in different forms become a great threat to human health. Such anti-platelet aggregation drugs as aspirin and clopidogrel are common drugs in clinic. However, along with the appearance of resistance and side effects of western anti-platelet aggregation drugs, anti-platelet aggregation traditional Chinese medicines promoting blood circulation to remove blood stasis have gradually become an important study orientation. Platelet is one of major participant in thrombosis, and plays an important role as a bioactive material in studies on traditional Chinese medicines promoting blood circulation to remove blood stasis, mainly involving two aspects--the evaluation for the anti-platelet aggregation activity of traditional Chinese medicines and the screening of their active components. This paper summarized the applications of platelets in studies on traditional Chinese medicines promoting blood circulation to remove blood stasis, so as to provide basis for further studies.
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Ren, Jian-xun; Liu, Jian-xun; Lin, Cheng-ren
2010-04-01
To comparatively analyse the objective characteristics of different syndrome types of qi-disturbance-induced blood stasis syndrome (QDBS) in the pathogenetic evolution of unstable angina coronary heart disease (UA-CHD). Seventy-eight patients with UA-CHD of QDBS were differentiated into 2 groups: 55 in the qi-deficiency-induced blood-stasis syndrome group (A) and 23 in the qi-stagnation-induced blood-stasis syndrome group (B). The comparative analysis on them was carried out through comparing their blood pressure, glucose and lipid metabolisms, coagulation function, thyroid function and inflammation reaction changes, etc. In the pathogenetic process of qi-disturbance induced blood stasis, the initiating age, levels of HbA1c, TSH, PT and APTT between the two groups were significantly different (P emotional stress is possibly the essence of qi-stagnation induced blood stasis syndrome.
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The Treatment of Geological Time & the History of Life on Earth in High School Biology Textbooks
Summers, Gerald; Decker, Todd; Barrow, Lloyd
2007-01-01
In spite of the importance of geological time in evolutionary biology, misconceptions about historical events in the history of life on Earth are common. Glenn (1990) has documented a decline from 1960 to 1989 in the amount of space devoted to the history of life in high school earth science textbooks, but we are aware of no similar study in…
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Energy Technology Data Exchange (ETDEWEB)
Park, Ah Young; Yu, Jeong Sik; Choi, Seung Ho; Chung, Jae Joon; Kim, Joo Hee; Kim, Ki Whang [Yonsei University College of Medicine, Gangnam Severance Hospital, Seoul (Korea, Republic of)
2013-01-15
This study aimed to compare the degree of gastric food stasis and following body fat changes after laparoscopic subtotal gastrectomy (LSTG) versus open subtotal gastrectomy (OSTG). For 284 consecutive gastric cancer patients who underwent subtotal gastrectomy (213 LSTG and 71 OSTG), the one-year follow-up CT images were reviewed retrospectively. The characteristics of gastric stasis was divided into 5 degrees (0, no residue; 1, small secretion; 2, poorly-defined amorphous food; 3, well-delineated measurable food; 4, bezoar-like food). The residual food volume was calculated for the patients with degree 3 or 4 gastric stasis. Postoperative visceral, subcutaneous, and total fat changes were measured on CT and were correlated with the residual food volume. The LSTG group showed higher degrees of gastric stasis [degree 3 (LSTG, 15.0%; OSTG, 9.9%), degree 4 (LSTG, 6.5%; OSTG, 2.8%)] (p = 0.072). The mean residual food volume of the LSTG group was larger than that of the OSTG group (13779 cc versus 6295 cc) (p = 0.059). Postoperative abdominal fat change was not significantly different between the 2 groups and was not correlated with the residual food volume. LSTG tends to develop gastric stasis more frequently compared with OSTG, but gastric stasis might hardly affect the postoperative body fat status.
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Simple versus complex models of trait evolution and stasis as a response to environmental change
Hunt, Gene; Hopkins, Melanie J.; Lidgard, Scott
2015-04-01
Previous analyses of evolutionary patterns, or modes, in fossil lineages have focused overwhelmingly on three simple models: stasis, random walks, and directional evolution. Here we use likelihood methods to fit an expanded set of evolutionary models to a large compilation of ancestor-descendant series of populations from the fossil record. In addition to the standard three models, we assess more complex models with punctuations and shifts from one evolutionary mode to another. As in previous studies, we find that stasis is common in the fossil record, as is a strict version of stasis that entails no real evolutionary changes. Incidence of directional evolution is relatively low (13%), but higher than in previous studies because our analytical approach can more sensitively detect noisy trends. Complex evolutionary models are often favored, overwhelmingly so for sequences comprising many samples. This finding is consistent with evolutionary dynamics that are, in reality, more complex than any of the models we consider. Furthermore, the timing of shifts in evolutionary dynamics varies among traits measured from the same series. Finally, we use our empirical collection of evolutionary sequences and a long and highly resolved proxy for global climate to inform simulations in which traits adaptively track temperature changes over time. When realistically calibrated, we find that this simple model can reproduce important aspects of our paleontological results. We conclude that observed paleontological patterns, including the prevalence of stasis, need not be inconsistent with adaptive evolution, even in the face of unstable physical environments.
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History of satellite missions and measurements of the Earth Radiation Budget (1957-1984)
House, F. B.; Gruber, A.; Hunt, G. E.; Mecherikunnel, A. T.
1986-01-01
The history of satellite missions and their measurements of the earth radiation budget from the beginning of the space age until the present time are reviewed. The survey emphasizes the early struggle to develop instrument systems to monitor reflected shortwave and emitted long-wave exitances from the earth, and the problems associated with the interpretation of these observations from space. In some instances, valuable data sets were developed from satellite measurements whose instruments were not specifically designed for earth radiation budget observations.
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Badger, Marcus P. S.; Pancost, Richard D.; Harrison, Timothy G.
2011-01-01
The reconstruction of ancient atmospheric carbon dioxide concentrations is essential to understanding the history of the Earth and life. It is also an important guide to identifying the sensitivity of the Earth system to this greenhouse gas and, therefore, constraining its future impact on climate. However, determining the concentration of…
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Gianfaldoni, S; Wollina, U; Lotti, J; Gianfaldoni, R; Lotti, T; Fioranelli, M; Roccia, M G
To retrieve the history of venous ulcers and of skin lesions in general, we must go back to the appearance of human beings on earth. It is interesting to note that cutaneous injuries evolved parallel to human society. An essential first step in the pathogenesis of ulcers was represented by the transition of the quadruped man to Homo Erectus. This condition was characterized by a greater gravitational pressure on the lower limbs, with consequences on the peripheral venous system. Furthermore, human evolution was characterized by an increased risk of traumatic injuries, secondary to his natural need to create fire and hunt (e.g. stones, iron, fire, animal fighting). Humans then began to fight one another until they came to real wars, with increased frequency of wounds and infectious complications. The situation degraded with the introduction of horse riding, introduced by the Scites, who first tamed animals in the 7th century BC. This condition exhibited iliac veins at compression phenomena, favouring the venous stasis. With time, man continued to evolve until the modern age, which is characterized by increased risk factors for venous wounds such as poor physical activity and dietary errors (1, 2).
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Impacts and tectonism in Earth and moon history of the past 3800 million years
Stothers, Richard B.
1992-01-01
The moon's surface, unlike the Earth's, displays a comparatively clear record of its past bombardment history for the last 3800 Myr, the time since active lunar tectonism under the massive premare bombardment ended. From Baldwin's (1987) tabulation of estimated ages for a representative sample of large lunar craters younger than 3800 Ma, six major cratering episodes can be discerned. These six bombardment episodes, which must have affected the Earth too, appear to match in time the six major episodes of orogenic tectonism on Earth, despite typical resolution errors of +/- 100 Myr and the great uncertainties of the two chronologies. Since more highly resolved events during the Cenozoic and Mesozoic Eras suggest the same correlation, it is possible that large impacts have influenced plate tectonics and other aspects of geologic history, perhaps by triggering flood basalt eruptions.
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Erices, Rainer; Frewer, Andreas; Gumz, Antje
2018-01-01
After the building of the Berlin Wall in the 1960s, a number of international pharmaceutical manufacturers from the West had their drugs tested in Eastern Germany (GDR). So far, the extensive collection of documents on the subject stored in the archives of the GDR State Security Service (Stasi, MfS) has not been systematically analysed. Until now, the role of the Stasi with respect to the surveillance of the trials has been unclear. A keyword search within the database of the Stasi files was conducted. All available files were screened in order to identify institutions, companies and personnel involved in the clinical trials. On this basis, further files were requested. A total of 259 files were available for analysis. Relevant data was derived from 160 of these files. A contextualised approach was applied, which critically explored the origin, content, and impact of the data. In addition, an approach guided by the central steps of document analysis was applied. At least 400 clinical trials were conducted during the GDR period. The exact number remains speculative. According to references found in the Stasi files, it might have been considerably higher. Initially, the main goal of the trials was for the GDR authorities to decide whether to import certain Western drugs. By 1983, this intention had changed. Now, the primary aim of the trials was the procurement of foreign currency. The Stasi feared that the pharmaceutical companies could have a significant influence on GDR Health System. Stasi spies were holding positions in the responsible medical committees, universities, and hospitals. Constant surveillance by the Stasi served the purpose of monitoring any contact between people from the West and the East. Unknowingly, representatives of Western companies were surveilled by the Stasi. The studied documents also point to the fact that a number of clinical trials conducted during the GDR period did not comply with GDR regulations, and were therefore deemed illegal
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Epidural venous stasis in spinal stenosis
International Nuclear Information System (INIS)
Kaiser, M.C.; Capesius, P.; Poos, D.; Gratia, G.; Roilgen, A.; Sandt, G.
1984-01-01
Computed tomography permits reliable demonstration of the spinal canal and its contents. Measurements of the sagittal diameter of the bony canal do not take into consideration size, shape and state of intraspinal soft tissue structures, i.e. the thecal sac and its own contents, epidural fat and blood circulation pattern. Three particularly illustrative cases were selected in which obvious epidural venous engorgement was visualized in association with spinal stenosis. The authors think that epidural venous stasis occuring in segmental spinal stenosis is a CT sign of clinically significant narrowing of the neural canal. Accurate recognition of the type of lumbar stenosis together with epidural blood flow alterations permits a better understanding of the existing lesions. Thus, a more precise and specific surgical approach is possible. (orig.)
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Early history of Earth's crust-mantle system inferred from hafnium isotopes in chondrites
DEFF Research Database (Denmark)
Bizzarro, Martin; Haack, Henning; Rosing, M.
2003-01-01
for the chondrite-forming event. This ¿176 value indicates that Earth's oldest minerals were derived from melts of a mantle source with a time-integrated history of depletion rather than enrichment. The depletion event must have occurred no later than 320 Myr after planetary accretion, consistent with timing......The Lu to Hf decay series has been widely used to understand the nature of Earth's early crust-mantle system. The interpretation, however, of Lu-Hf isotope data requires accurate knowledge of the radioactive decay constant of Lu (¿176), as well as bulk-Earth reference parameters. A recent...
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Seeing the History of the Earth in the Cliffs at Møn
DEFF Research Database (Denmark)
Hedin, Gry
2013-01-01
During the first part of the nineteenth century, geologists developed a history of the earth so different from that accepted in previous centuries that it encouraged a rethinking of the relationship between man and nature. In this article I will argue that painters followed these changes closely ...
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Wang, Ye; Yang, Jia-mei; Hou, Yuan-kai; Li, Dian-qi; Hu, Ming-hua; Liu, Peng
2008-04-15
To investigate the effect and mechanism of portal blood stasis on lung and renal injury induced by hepatic ischemia reperfusion. A rabbit hepatic ischemia reperfusion injury model was established by hepatic portal occlusion and in situ hypothermic irrigation for 30 min. Twenty-four New Zealand white rabbits were employed and randomly divided into 3 groups equally by different dosage of portal blood stasis removal: group A5 (5 ml blood removal), group A10 (10 ml blood removal),and group B (no blood removal). Eight rabbits were served as controls with no hepatic portal occlusion and hypothermic irrigation. After reperfusion 4 h serum endotoxin content, tumor necrosis factor-alpha (TNF-alpha), urea nitrogen (BUN), and creatinine (Cr) were examined respectively, meantime lung and kidney tissues were sampled to determine the content of malondialdehyde (MDA), superoxide dismutase (SOD), the pathology, and wet to dry weight ratio, broncho-alveolar lavage fluid protein content in lung tissues. Removing portal blood stasis ameliorated lung and renal injury as shown by decreasing the level of serum endotoxin, TNF-alpha, BUN, Cr, wet to dry weight ratio, broncho-alveolar lavage fluid protein content, MDA, SOD. TNF-alpha, Cr, broncho-alveolar lavage fluid protein content in lung tissues and MDA in kidney tissue in group A5 were significantly reduced compared with those in group B (P portal blood stasis before the resume of splanchnic circulation may ameliorate the lung and renal injury induced by hepatic ischemia reperfusion. The possible mechanism may be that portal blood stasis removal reduces endotoxin absorption, and further decreases production of serum TNF-alpha.
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Directory of Open Access Journals (Sweden)
A. Meillier
2018-01-01
Conclusions: Achalasia subtypes had similar clinical symptoms, except for increased vomiting severity in subtype i. The maximum esophageal diameter in subtype ii was significantly greater than in subtype iii. Esophageal stasis scores were similar. Thus, high-resolution esophageal manometry remains essential in assessing achalasia subtypes.
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Early evolution of the earth - Accretion, atmosphere formation, and thermal history
Abe, Yutaka; Matsui, Takafumi
1986-01-01
The thermal and atmospheric evolution of the earth growing planetesimal impacts are studied. The generation of an H2O protoatmosphere is examined, and the surface temperatures are estimated. The evolution of an impact-induced H2O atmosphere is analyzed. Consideration is given to the formation time of a 'magma ocean'and internal water budgets. The thermal history of an accreting earth is reviewed. The wet convection and greenhouse effects are discussed, and the role of Fe oxidation on the evolution of an impact-induced H2O atmopshere is described. The relationship between differentiation processes and core segregation, the H2O and FeO content of the mantle, and the origin of the hydrosphere is also examined.
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Role of ionizing radiation in the natural history of the Earth
International Nuclear Information System (INIS)
Byakov, V.M.; Stepanov, S.V.; Stepanova, O.P.
2001-01-01
A role of ionizing radiation in some global processes and events in geological history of the Earth is considered. In particular, we discuss: (1) the influence of ionizing radiation from radioactive nuclei disseminated in sedimentary rocks on the transformation of terrestrial organic matter into stone coals and oil; (2) the effect of cosmic rays from Supernova stars as a common cause of quasi-regular global geological processes and biocatastrophes. (author)
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Directory of Open Access Journals (Sweden)
Yi Jin
2017-10-01
Full Text Available The compatibility between Danggui (Angelicae Sinensis Radix and Honghua (Carthami Flos is a known herb pair, which could activate blood circulation and dissipate blood stasis effects. In this paper, we quantified seven main bio-active components (hydroxysafflor yellow A, caffeic acid, p-coumaric acid, kaempferol-3-O-rutinoside, ferulic acid, 3-n-butylphthalide, and ligustilide in plasma samples in vivo by UPLC-TQ/MS method and investigatedwhether the pharmacokinetic (PK behaviors of the seven components could be altered in blood stasis rats after oral administration of the Gui-Hong extracts. It was found that the Cmax and AUC0-t of these components in blood stasis rats had increasing tendency compared with normal rats. Most components in model and normal rats had significant difference in some pharmacokinetic parameters, which indicated that the metabolism enzymes and transporters involved in the metabolism and disposition of these bio-active componentsmay bealtered in blood stasis rats. This study was the first report about the pharmacokinetic investigation between normal and blood stasis rats after oral administrationof Gui-Hong extracts, and these results are important and valuable for better clinical applications of Gui-Hong herb pair and relatedTCM formulae.
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RECONSTRUCTING THE PHOTOMETRIC LIGHT CURVES OF EARTH AS A PLANET ALONG ITS HISTORY
International Nuclear Information System (INIS)
Sanromá, E.; Pallé, E.
2012-01-01
By utilizing satellite-based estimations of the distribution of clouds, we have studied Earth's large-scale cloudiness behavior according to latitude and surface types (ice, water, vegetation, and desert). These empirical relationships are used here to reconstruct the possible cloud distribution of historical epochs of Earth's history such as the Late Cretaceous (90 Ma ago), the Late Triassic (230 Ma ago), the Mississippian (340 Ma ago), and the Late Cambrian (500 Ma ago), when the landmass distributions were different from today's. With this information, we have been able to simulate the globally integrated photometric variability of the planet at these epochs. We find that our simple model reproduces well the observed cloud distribution and albedo variability of the modern Earth. Moreover, the model suggests that the photometric variability of the Earth was probably much larger in past epochs. This enhanced photometric variability could improve the chances for the difficult determination of the rotational period and the identification of continental landmasses for a distant planets.
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Sunderlin, David
2009-01-01
The complexity and interrelatedness of aspects of the geosciences is an important concept to convey in an undergraduate geoscience curriculum. A synthesis capstone project has served to integrate pattern-based learning of an introductory Earth History course into an active and process-based exercise in hypothesis production. In this exercise,…
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Coriocarcinoma con metástasis pulmonar
Directory of Open Access Journals (Sweden)
Vicia Sánchez Abalos
2014-05-01
Full Text Available Se presenta el caso clínico de una fémina de 44 años de edad, con 32 semanas de embarazo, la cual fuera ingresada en la Unidad de Cuidados Intensivos del Hospital General Docente "Dr. Juan Bruno Zayas Alfonso" de Santiago de Cuba, por presentar insuficiencia respiratoria aguda como consecuencia de una sepsis. La paciente fue tratada con cefalosporina de tercera generación y ventilación mecánica no invasiva, pero se mantuvieron las características gasométricas de hipoxemia y una mala reacción terapéutica, por lo que se requirió instrumentación de las vías respiratorias y soporte hemodinámico, sin lograr regresión del cuadro clínico, lo cual condujo a un paro cardiorrespiratorio y, con ello, a la muerte. La necropsia mostró un coriocarcinoma del endometrio con metástasis pulmonar
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Abrupt global events in the Earth's history: a physics perspective
International Nuclear Information System (INIS)
Ryskin, Gregory
2010-01-01
The timeline of the Earth's history reveals quasi-periodicity of the geological record over the last 542 Myr, on timescales close, in the order of magnitude, to 1 Myr. What is the origin of this quasi-periodicity? What is the nature of the global events that define the boundaries of the geological time scale? I propose that a single mechanism is responsible for all three types of such events: mass extinctions, geomagnetic polarity reversals, and sea-level fluctuations. The mechanism is fast, and involves a significant energy release. The mechanism is unlikely to have astronomical causes, both because of the energies involved and because it acts quasi-periodically. It must then be sought within the Earth itself. And it must be capable of reversing the Earth's magnetic field. The last requirement makes it incompatible with the consensus model of the origin of the geomagnetic field-the hydromagnetic dynamo operating in the Earth's fluid core. In the second part of the paper, I show that a vast amount of seemingly unconnected geophysical and geological data can be understood in a unified way if the source of the Earth's main magnetic field is a ∼200 km thick lithosphere, repeatedly magnetized as a result of methane-driven oceanic eruptions, which produce ocean flow capable of dynamo action. The eruptions are driven by the interplay of buoyancy forces and exsolution of dissolved gas, which accumulates in the oceanic water masses prone to stagnation and anoxia. Polarity reversals, mass extinctions and sequence boundaries are consequences of these eruptions. Unlike the consensus model of geomagnetism, this scenario is consistent with the paleomagnetic data showing that 'directional changes during a reversal can be astonishingly fast, possibly occurring as a nearly instantaneous jump from one inclined dipolar state to another in the opposite hemisphere'.
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Huang, Shuai; Xu, Feng; Wang, Yin-Ye; Shang, Ming-Ying; Wang, Chao-Qun; Wang, Xuan; Cai, Shao-Qing
2014-12-23
To establish a novel cardiocentesis method for withdrawing venous blood from the right atrium, and to improve an acute blood stasis rat model using an ice bath and epinephrine hydrochloride (Epi) while considering the 3Rs (reduction, refinement, and replacement) of humane animal experimentation. An acute blood stasis model was established in male Sprague-Dawley rats by subcutaneous injection (s.c.) Epi (1.2 mg/kg) administration at 0 h, followed by a 5-min exposure to an ice-bath at 2 h and s.c. Epi administration at 4 h. Control rats received physiological saline. Rats were fasted overnight and treated with Angelicae Sinensis Lateralis Radix (ASLR) and Pheretima the following day. Venous blood was collected using our novel cardiocentesis method and used to test whole blood viscosity (WBV), prothrombin time (PT), activated partial thromboplastin time (APTT), and fibrinogen (FIB) content. The rats survived the novel cardiocentesis technique; WBV value returned to normal while hematological parameters such as hemoglobin level and red blood cell count were restored to >94% of the corresponding values in normal rats following a 14-day recovery. Epi (1.2 mg/kg, s.c.) combined with a 5-min exposure to the ice bath replicated the acute blood stasis rat model and was associated with the highest WBV value. In rats showing acute blood stasis, ASLR treatment [4 g/(kg·d) for 8 days] decreased WBV by 9.98%, 11.09%, 9.34%, 9.00%, 7.66%, and 7.03% (P<0.05), while Pheretima treatment [2.6 g/(kg·d), for 8 days] decreased WBV by 25.49%, 25.94%, 16.28%, 17.76%, 11.07%, and 7.89% (P<0.01) at shear rates of 1, 3, 10, 30, 100, and 180 s -1 , respectively. Furthermore, Pheretima treatment increased APTT significantly (P<0.01). We presented a stable, reproducible, and improved acute blood stasis rat model, which could be applied to screen drugs for promoting blood circulation and eliminating blood stasis.
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Earth observations from space: History, promise, and reality. Executive summary
1995-01-01
In this report the Committee on Earth Studies (CES), a standing committee of the Space Studies Board (SSB) within the National Research Council (NRC), reviews the recent history (nominally from 1981 to 1995) of the U.S. earth observations programs that serve civilian needs. The principal observations programs examined are those of NASA and the National Oceanic and Atmospheric Administration (NOAA). The Air Force' s Defense Meteorological Satellite Program (DMSP) is discussed, but only from the perspective of its relationship to civil needs and the planned merger with the NOAA polar-orbiting system. The report also reviews the interfaces between the earth observations satellite programs and the major national and international environmental monitoring and research programs. The monitoring and research programs discussed are the U.S. Global Change Research Program (USGCRP), the International Geosphere-Biosphere Program (IGBP), the World Climate Research Program (WCRP), related international scientific campaigns, and operational programs for the sharing and application of environmental data. The purpose of this report is to provide a broad historical review and commentary based on the views of the CES members, with particular emphasis on tracing the lengthy record of advisory committee recommendations. Any individual topic could be the subject of an extended report in its own right. Indeed, extensive further reviews are already under way to that end. If the CES has succeeded in the task it has undertaken. This report will serve as a useful starting point for any such more intensive study. The report is divided into eight chapters: ( I ) an introduction, (2) the evolution of the MTPE, (3) its relationship to the USGCRP, (4) applications of earth observations data, (5) the role that smaller satellites can play in research and operational remote sensing, (6) earth system modeling and information systems, (7) a number of associated activities that contribute to the MTPE
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Effect of Qing Nao tablet on blood stasis model of mice
Kong, Xuejun; Hao, Shaojun; Wang, Hongyu; Liu, Xiaobin; Xie, Guoqi; Li, Wenjun; Zhang, Zhengchen
2018-04-01
To investigate the effect of Qing Nao tablet on mouse model of blood stasis syndrome, 60 mice, male and female, were randomly divided into 6 groups, were fed with large, small doses of Qing Nao tablet suspension, Naoluotong saline suspension and the same volume (group 2, 0.1ml/10g), administer 1 times daily, orally for 15 days. Intragastric administration for first days, in addition to the 1 group saline group every day in the hind leg intramuscular saline, the other 5 groups each rat day hind leg muscle injection of dexamethasone 0.8mg/kg intramuscular injection every day, 1 times, 15 days. 1 hour continuous intramuscular injection and intramuscular drug perfusion on the sixteenth day after mice. The eyeball blood, heparin after whole blood viscosity test. Compared with the control group, model group, high and low shear viscosity were significantly increased (Pgroup, high dose group and Qing Nao tablet Naoluotong group can significantly reduce the viscosity at high shear and (Pgroup can significantly reduce high shear and shear viscosity (Pgroup can significantly reduce the low shear viscosity (Pgroup can significantly reduce the low shear viscosity (Pgroup were lower high cut, low shear viscosity and trend The potential (P>0.05). The Qing Nao tablet has a good effect on the model of blood stasis in mice.
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Microbial stasis of Leishmania enriettii in activated guinea pig macrophages
International Nuclear Information System (INIS)
Groocock, C.M.; Soulsby, E.J.L.
1980-01-01
Peritoneal exudate cells (PEC) from Leishmania-sensitized guinea pigs were cultured in vitro in the presence (activated) or absence (non-activated) of leishmanial antigen for 24 or 48 hours. These were then labelled with 51 Cr and challenged with 125 I-labelled promastigotes. The changing relationship between the macrophage and the parasite was monitored by observing changes in the ratio of the cell-associated isotopes. Highly significant differences in the ratio change developed during culture. These differences were a result of the activated cultures showing a higher release of 51 Cr and a lower release of 125 I when compared with the non-activated cells, at 12 hours the percentage release of 125 I from the parasite within the activated macrophage was fourfold less than that released by parasites within non-activated cells (9.2% versus 38.3%) and tenfold less than that released from glutaraldehyde-killed organisms phagocytosed by activated macrophages (91.6%). These studies indicate that stasis rather than killing of leishmaniae occurs in the activated macrophage in vitro. Parallel experiments evaluated by the visual counting of leishmaniae within the macrophages support these data. PEC from tuberculin-sensitized guinea pigs activated in vitro by purified protein derivative showed little or no activity against leishmaniae, indicating a specific requirement for this microbial stasis by activated macrophages. As a corollary of this, peritoneal exudate lymphocytes separated from the same preparations of PEC were shown to be specifically reactive to leishmanial antigen by transformation and incorporation of 3 H-thymidine. (author)
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Becknell, Brian; Mohamed, Ahmad Z.; Li, Birong; Wilhide, Michael E.; Ingraham, Susan E.
2015-01-01
Purpose Urinary stasis is a risk factor for recurrent urinary tract infection (UTI). Homozygous mutant Megabladder (Mgb-/-) mice exhibit incomplete bladder emptying as a consequence of congenital detrusor aplasia. We hypothesize that this predisposes Mgb-/- mice to spontaneous and experimental UTI. Methods Mgb-/-, Mgb+/-, and wild-type female mice underwent serial ultrasound and urine cultures at 4, 6, and 8 weeks to detect spontaneous UTI. Urine bacterial isolates were analyzed by Gram stain and speciated. Bladder stones were analyzed by x-ray diffractometry. Bladders and kidneys were subject to histologic analysis. The pathogenicity of coagulase-negative Staphylococcus (CONS) isolated from Mgb-/- urine was tested by transurethral administration to culture-negative Mgb-/- or wild-type animals. The contribution of urinary stasis to CONS susceptibility was evaluated by cutaneous vesicostomy in Mgb-/- mice. Results Mgb-/- mice develop spontaneous bacteriuria (42%) and struvite bladder stones (31%) by 8 weeks, findings absent in Mgb+/- and wild-type controls. CONS was cultured as a solitary isolate from Mgb-/- bladder stones. Bladders and kidneys from mice with struvite stones exhibit mucosal injury, inflammation, and fibrosis. These pathologic features of cystitis and pyelonephritis are replicated by transurethral inoculation of CONS in culture-negative Mgb-/- females, whereas wild-type animals are less susceptible to CONS colonization and organ injury. Cutaneous vesicostomy prior to CONS inoculation significantly reduces the quantity of CONS recovered from Mgb-/- urine, bladders, and kidneys. Conclusions CONS is an opportunistic uropathogen in the setting of urinary stasis, leading to enhanced UTI incidence and severity in Mgb-/- mice. PMID:26401845
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Communicating the History of the Earth
Gaonac'h, H.
2009-05-01
There is much to be learned from the relationship between scientific academic research and the way the public understands and perceives natural geological phenomena including catastrophic situations. While news about science discoveries or accidents is disseminated more and more rapidly than ever, its scientific content is still very low and usually not easy to understand - except for a small community of experts. On the other hand, scientists are increasingly able to predict - at least to some degree - catastrophes such as volcanic eruptions, flooding, landslides, etc. There is thus an urgency to better disseminate to the public the understanding of these natural events but with deeper perspectives that will provoke critical reactions from the public and thus proactive ways to access to knowledge. One particular point is to provide easy, non-dramatic scientific experience to young people. My own efforts in this direction started in 2002 with youth oriented outreach Web site 'Les Chroniques volcaniques avec Vicki Volka'. Over the years it has evolved and spawned a children's book about volcanoes, educational fact sheets, visits to schools, field geological excursions for the public and last year a day camp for 8-12 year olds. Supported through my research centre, GEOTOP, I have been able to put efforts towards a large range of ages. I will explain the most recent experience we conducted via the summer scientific 'academic' camp, starting last year with one theme about volcanoes and continuing this year with a complementary theme about fossils and Earth History. One key point is to introduce young people with many different ways to achieve scientific objectives and to encourage them to reproduce their results in front of a familiar audience (their families): this is a good way to lead the future generations to a high level of understanding of their environment, natural history as well as to taking responsibilities in front of crucial issues.
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The Anthropocene era. The Earth, the history and us
International Nuclear Information System (INIS)
Bonneuil, Christophe; Fressoz, Jean-Baptiste
2013-01-01
As some scientists state that the Earth entered the Anthropocene era which is an anthropogenic geological revolution: the traces of our urban, consumption, chemical and nuclear era will remain in the planet geological archives for thousands and even millions of years, and will result in huge difficulties for human societies. Between science and history, the authors give an overview of a development model which has become unsustainable: studies which highlighted the impossibility of an indefinite growth in the 1970's have been ignored, and instead of taking the three dimensions involved in sustainable development (economy, social, environment), into account, environment tends to become only a new item in firm accounting (markets of eco-systemic services, the biosphere, hydrosphere and atmosphere about to become simple subsystems of the financial and merchandising sphere)
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Astrobiology, history, and society life beyond earth and the impact of discovery
2013-01-01
This book addresses important current and historical topics in astrobiology and the search for life beyond Earth, including the search for extraterrestrial intelligence (SETI). The first section covers the plurality of worlds debate from antiquity through the nineteenth century, while section two covers the extraterrestrial life debate from the twentieth century to the present. The final section examines the societal impact of discovering life beyond Earth, including both cultural and religious dimensions. Throughout the book, authors draw links between their own chapters and those of other contributors, emphasizing the interconnections between the various strands of the history and societal impact of the search for extraterrestrial life. The chapters are all written by internationally recognized experts and are carefully edited by Douglas Vakoch, professor of clinical psychology at the California Institute of Integral Studies and Director of Interstellar Message Composition at the SETI Institute. This interd...
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International Nuclear Information System (INIS)
Nakanishi, Tadashi; Hamada, Seiki; Takamiya, Makoto; Kuribayashi, Sachio; Naito, Hiroaki
1994-01-01
The left-atrial appendage (LAA) is the most frequent site of thrombus formation. The most probable reason is its anatomical structure and blood stasis. We hypothesized that peak time delay should occur in the LAA with stagnant blood flow. We measured peak time delay in LAA against left atrium with the flow-mode study of electron-beam CT for 49 patients (including 23 patients with atrial fibrillation [AF]). Volume-mode scannings were also performed to detect intracardiac thrombi. Patients with atrial fibrillation showed a larger value than those with sinus rhythm. Some AF patients with no filling of contrast media into the LAA and/or thrombus showed a larger value than the others. The value obtained by the flow-mode study might have the potential by the flow-mode study might have the potential to assess blood stasis and to predict the jeopardized state in the LAA. (orig.)
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Energy Technology Data Exchange (ETDEWEB)
Nakanishi, Tadashi [Dept. of Radiology, National Cardiovascular Center, Suita, Osaka (Japan); Hamada, Seiki [Dept. of Radiology, National Cardiovascular Center, Suita, Osaka (Japan); Takamiya, Makoto [Dept. of Radiology, National Cardiovascular Center, Suita, Osaka (Japan); Kuribayashi, Sachio [Dept. of Radiology, National Cardiovascular Center, Suita, Osaka (Japan); Naito, Hiroaki [Biomedical Research Center, Osaka Univ. School of Medicine, Suita (Japan)
1994-10-01
The left-atrial appendage (LAA) is the most frequent site of thrombus formation. The most probable reason is its anatomical structure and blood stasis. We hypothesized that peak time delay should occur in the LAA with stagnant blood flow. We measured peak time delay in LAA against left atrium with the flow-mode study of electron-beam CT for 49 patients (including 23 patients with atrial fibrillation [AF]). Volume-mode scannings were also performed to detect intracardiac thrombi. Patients with atrial fibrillation showed a larger value than those with sinus rhythm. Some AF patients with no filling of contrast media into the LAA and/or thrombus showed a larger value than the others. The value obtained by the flow-mode study might have the potential by the flow-mode study might have the potential to assess blood stasis and to predict the jeopardized state in the LAA. (orig.)
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Biological Evolution and the History of the Earth Are Foundations of Science
2008-01-01
AGU affirms the central importance of including scientific theories of Earth history and biological evolution in science education. Within the scientific community, the theory of biological evolution is not controversial, nor have ``alternative explanations'' been found. This is why no competing theories are required by the U.S. National Science Education Standards. Explanations of natural phenomena that appeal to the supernatural or are based on religious doctrine-and therefore cannot be tested through scientific inquiry-are not scientific, and have no place in the science classroom.
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Energy Technology Data Exchange (ETDEWEB)
Mutterlose, J.; Immenhauser, A. [Bochum Univ. (Germany). Inst. fuer Geologie, Mineralogie und Geophysik, Sediment- und Isotopengeologie/Geobiologie
2007-07-01
The impending global warning is one of the biggest challenges to be faced by humanity. A look back into Earth's history may be useful for describing and understanding the future scenario. Paleooceanographers, paleontologists and sedimentologists analyze the climates throughout Earth history, in which there were several periods of 'greenhouse conditions'. (orig.)
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Ozone control of biological activity during Earth's history, including the KT catastrophe
Sheldon, W. R.
1994-01-01
There have been brief periods since the beginning of the Cambrian some 600 m.y. ago when mass extinctions destroyed a significant fraction of living species. The most widely studied of these events is the catastrophe at the KT boundary that ended the long dominance of the dinosaurs. In addition to mass extinctions, there is another profound discontinuity in the history of Earth's biota, the explosion of life at the end of the Precambrian era which is an episode that is not explained well at all. For some 3 b.y. before the Cambrian, life had been present on Earth, but maintained a low level of activity which is an aspect of the biota that is puzzling, especially during the last two-thirds of that period. During the last 2 b.y. before the Cambrian, conditions at the Earth's surface were suitable for a burgeoning of the biota, according to most criteria: the oceans neither boiled nor were fozen solid during this time, and the atmosphere contained sufficient O for the development of animals. The purpose of this paper is to suggest that mass extinctions and the lackluster behavior of the Precambrian biota share a common cause: an inadequate amount of ozone in the atmosphere.
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Abrupt global events in the Earth's history: a physics perspective
Energy Technology Data Exchange (ETDEWEB)
Ryskin, Gregory, E-mail: ryskin@northwestern.ed [Robert R McCormick School of Engineering and Applied Science, Northwestern University, Evanston, IL 60208 (United States)
2010-12-01
The timeline of the Earth's history reveals quasi-periodicity of the geological record over the last 542 Myr, on timescales close, in the order of magnitude, to 1 Myr. What is the origin of this quasi-periodicity? What is the nature of the global events that define the boundaries of the geological time scale? I propose that a single mechanism is responsible for all three types of such events: mass extinctions, geomagnetic polarity reversals, and sea-level fluctuations. The mechanism is fast, and involves a significant energy release. The mechanism is unlikely to have astronomical causes, both because of the energies involved and because it acts quasi-periodically. It must then be sought within the Earth itself. And it must be capable of reversing the Earth's magnetic field. The last requirement makes it incompatible with the consensus model of the origin of the geomagnetic field-the hydromagnetic dynamo operating in the Earth's fluid core. In the second part of the paper, I show that a vast amount of seemingly unconnected geophysical and geological data can be understood in a unified way if the source of the Earth's main magnetic field is a {approx}200 km thick lithosphere, repeatedly magnetized as a result of methane-driven oceanic eruptions, which produce ocean flow capable of dynamo action. The eruptions are driven by the interplay of buoyancy forces and exsolution of dissolved gas, which accumulates in the oceanic water masses prone to stagnation and anoxia. Polarity reversals, mass extinctions and sequence boundaries are consequences of these eruptions. Unlike the consensus model of geomagnetism, this scenario is consistent with the paleomagnetic data showing that 'directional changes during a reversal can be astonishingly fast, possibly occurring as a nearly instantaneous jump from one inclined dipolar state to another in the opposite hemisphere'.
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Li, Jun-Hui; Wu, Ya-Ling; Ye, Jian-Hong; Ning, Ya-Gong; Yu, Hai-Ying; Peng, Zhong-Jie; Luan, Xiao-Wen
2009-09-01
To observe the promoting effects of blood-activating and stasis-removing Chinese drugs combined with vascular endothelial growth factor (VEGF) gene transfer on angiogenesis in ischemic necrosis of the femoral head. Forty Japanese giant-ear rabbits were randomly divided into a control group, a model group, a Chinese drug group, a gene group, and a combined group. After 8 weeks of treatment, the rate of VEGF positive cell expression in the synovium of the femoral head was measured using the immunohistochemical method, and the number of blood vessels in the femoral head was measured by digital subtraction angiography. The rate of VEGF positive cell expression in the model group was significantly lower than that in the Chinese drug group (P 0.05). Either the blood-activating and stasis-removing Chinese drugs or VEGF gene transfer can promote the angiogenesis and building of collateral circulation for femoral head ischemic necrosis, and the combined therapy with Chinese drugs or VEGF gene transfer may show a better therapeutic effect. The present study provides an experimental basis for clinical application of the combined therapy with the blood-activating and stasis-removing Chinese drugs and VEGF gene transfer.
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Directory of Open Access Journals (Sweden)
Linlin Zhao
2014-01-01
Full Text Available A metabonomics approach based on liquid chromatography/quadrupole time-of-flight mass spectrometry (LC-Q-TOF/MS was utilized to obtain potential biomarkers of coronary heart disease (CHD patients and investigate the ZHENG types differentiation in CHD patients. The plasma samples of 20 CHD patients with phlegm syndrome, 20 CHD patients with blood-stasis syndrome, and 16 healthy volunteers were collected in the study. 26 potential biomarkers were identified in the plasma of CHD patients and 19 differential metabolites contributed to the discrimination of phlegm syndrome and blood-stasis syndrome in CHD patients (VIP>1.5; P<0.05 which mainly involved purine metabolism, pyrimidine metabolism, amino acid metabolism, steroid biosynthesis, and arachidonic acid metabolism. This study demonstrated that metabonomics approach based on LC-MS was useful for studying pathologic changes of CHD patients and interpreting the differentiation of ZHENG types (phlegm and blood-stasis syndrome in traditional Chinese medicine (TCM.
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Lu, Victor M; McDonald, Kerrie L; Townley, Helen E
2017-10-01
The prognosis of brain cancer glioblastoma (GBM) is poor, and despite intense research, there have been no significant improvements within the last decade. This stasis implicates the need for more novel therapeutic investigation. One such option is the use of nanoparticles (NPs), which can be beneficial due to their ability to penetrate the brain, overcome the blood-brain barrier and take advantage of the enhanced permeation and retention effect of GBM to improve specificity. Rare earth elements possess a number of interesting natural properties due to their unique electronic configuration, which may prove therapeutically advantageous in an NP formulation. The underexplored exciting potential for rare earth elements to augment the therapeutic potential of NPs in GBM treatment is discussed in this review.
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The history of the UV radiation climate of the earth--theoretical and space-based observations.
Cockell, C S; Horneck, G
2001-04-01
In the Archean era (3.8-2.5 Ga ago) the Earth probably lacked a protective ozone column. Using data obtained in the Earth's orbit on the inactivation of Bacillus subtilis spores we quantitatively estimate the potential biological effects of such an environment. We combine this practical data with theoretical calculations to propose a history of the potential UV stress on the surface of the Earth over time. The data suggest that an effective ozone column was established at a pO2 of approximately 5 x 10(-3) present atmospheric level. The improvement in the UV environment on the early Proterozoic Earth might have been a much more rapid event than has previously been supposed, with DNA damage rates dropping by two orders of magnitude in the space of just a few tens of millions of years. We postulate that a coupling between reduced UV stress and increased pO2 production could have contributed toward a positive feedback in the production of ozone in the early Proterozoic atmosphere. This would contribute to the apparent rapidity of the oxidation event. The data provide an evolutionary perspective on present-day Antarctic ozone depletion.
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Lu, Xiao-yan; Xu, Hao; Li, Geng; Zhao, Tie
2014-01-01
Studying the essence of a syndrome has been a key challenge in the field of Chinese medicine. Until now, due to limitations of the methods available, the progress towards understanding such complicated systems has been slow. Metabonomics encompasses the dynamics, composition and analysis of metabolites, enabling the observation of changes in the metabolic network of the human body associated with disease. Being from the point of view of the whole organism, metabonomics provides an opportunity to study the essence of a syndrome to an unprecedented level. Phlegm and blood stasis syndrome is the main syndrome associated with coronary heart disease (CHD), which bring difficulties in clinical treatment due to difficulties associated with differentiation of symptoms and signs. The fundamental differences of material between the two also need to be interpreted. The authors consider that we can use the method of combining a disease (in this case CHD) with associated syndromes (phlegm and blood stasis syndrome) to select patients with phlegm and blood stasis syndrome of CHD, and utilize metabonomics to explore the essence of the syndrome by difference analysis of metabolite spectra. Meanwhile, we can study the syndrome in CM, observe the change regularity of metabolism spectra after the treatment of corresponding and non-corresponding prescription and syndrome, in order to validate the material fundament in the progress of syndrome formation and their differences. This will not only have great significance in enhancing the ability to identify syndrome of phlegm and blood stasis in CHD and to establish the clinical curative criteria, but will also offer a new approach of studying the essence for a syndrome using metabonomics.
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Regeneració i homeòstasi a les planàries: gens i vies de senyalització implicats en l'organogènesi
González Sastre, Alejandro
2017-01-01
[cat] En aquesta tesi, titulada “Regeneració i homeòstasi a les planàries: gens i vies de senyalització implicats en l'organogènesi”, s’aprofundeix en l’estudi dels processos responsables de l’organogènesi a la planària d’aigua dolça Schmidtea mediterranea, tant durant la regeneració com durant l’homeòstasi. La planària d’aigua dolça Schmidtea mediterranea presenta una extraordinària capacitat de regeneració, gràcies a la presència d’una elevada quantitat de cèl·lules mare, els neoblasts, qu...
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Earth's Climate History from Glaciers and Ice Cores
Thompson, Lonnie
2013-03-01
Glaciers serve both as recorders and early indicators of climate change. Over the past 35 years our research team has recovered climatic and environmental histories from ice cores drilled in both Polar Regions and from low to mid-latitude, high-elevation ice fields. Those ice core -derived proxy records extending back 25,000 years have made it possible to compare glacial stage conditions in the Tropics with those in the Polar Regions. High-resolution records of δ18O (in part a temperature proxy) demonstrate that the current warming at high elevations in the mid- to lower latitudes is unprecedented for the last two millennia, although at many sites the early Holocene was warmer than today. Remarkable similarities between changes in the highland and coastal cultures of Peru and regional climate variability, especially precipitation, imply a strong connection between prehistoric human activities and regional climate. Ice cores retrieved from shrinking glaciers around the world confirm their continuous existence for periods ranging from hundreds to thousands of years, suggesting that current climatological conditions in those regions today are different from those under which these ice fields originated and have been sustained. The ongoing widespread melting of high-elevation glaciers and ice caps, particularly in low to middle latitudes, provides strong evidence that a large-scale, pervasive and, in some cases, rapid change in Earth's climate system is underway. Observations of glacier shrinkage during the 20th and 21st century girdle the globe from the South American Andes, the Himalayas, Kilimanjaro (Tanzania, Africa) and glaciers near Puncak Jaya, Indonesia (New Guinea). The history and fate of these ice caps, told through the adventure, beauty and the scientific evidence from some of world's most remote mountain tops, provide a global perspective for contemporary climate. NSF Paleoclimate Program
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Directory of Open Access Journals (Sweden)
Lidia Torres Aja
2012-09-01
Full Text Available En la evolución clínica de los tumores malignos, entre el 1 y el 10,4 % de estos se presentan metástasis cutáneas, por lo que se considera su presencia sinónimo de enfermedad rápidamente progresiva con bajos índices de supervivencia. En los varones, el tumor que más suele producirlas es el de pulmón y en las mujeres, el de mama. Es poco frecuente que la metástasis en la piel sea la primera manifestación del tumor, y es el carcinoma de mama el que con mayor frecuencia da lugar a esta eventualidad. En el caso que se presenta fue la metástasis en la piel la primera manifestación del tumor primario de mama subyacente.
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The thermal history of interplanetary dust particles collected in the Earth's stratosphere
Nier, A. O.; Schlutter, D. J.
1993-01-01
Fragments of 24 individual interplanetary dust particles (IDPs) collected in the Earth's stratosphere were obtained from NASA's Johnson Space Center collection and subjected to pulse-heating sequences to extract He and Ne and to learn about the thermal history of the particles. A motivation for the investigation was to see if the procedure would help distinguish between IDPs of asteroidal and cometary origin. The use of a sequence of short-duration heat pulses to perform the extractions is an improvement over the employment of a step-heating sequence, as was used in a previous investigation. The particles studied were fragments of larger parent IDPs, other fragments of which, in coordinated experiments, are undergoing studies of elemental and mineralogical composition in other laboratories. While the present investigation will provide useful temperature history data for the particles, the relatively large size of the parent IDPs (approximately 40 micrometers in diameter) resulted in high entry deceleration temperatures. This limited the usefulness of the study for distinguishing between particles of asteroidal and cometary origin.
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Prothero, Donald R.; Syverson, Valerie J.; Raymond, Kristina R.; Madan, Meena; Molina, Sarah; Fragomeni, Ashley; DeSantis, Sylvana; Sutyagina, Anastasiya; Gage, Gina L.
2012-11-01
Conventional neo-Darwinian theory views organisms as infinitely sensitive and responsive to their environments, and considers them able to readily change size or shape when they adapt to selective pressures. Yet since 1863 it has been well known that Pleistocene animals and plants do not show much morphological change or speciation in response to the glacial-interglacial climate cycles. We tested this hypothesis with all of the common birds (condors, golden and bald eagles, turkeys, caracaras) and mammals (dire wolves, saber-toothed cats, giant lions, horses, camels, bison, and ground sloths) from Rancho La Brea tar pits in Los Angeles, California, which preserves large samples of many bones from many well-dated pits spanning the 35,000 years of the Last Glacial-Interglacial cycle. Pollen evidence showed the climate changed from chaparral/oaks 35,000 years ago to snowy piñon-juniper forests at the peak glacial 20,000 years ago, then back to the modern chaparral since the glacial-interglacial transition. Based on Bergmann's rule, we would expect peak glacial specimens to have larger body sizes, and based on Allen's rule, peak glacial samples should have shorter and more robust limbs. Yet statistical analysis (ANOVA for parametric samples; Kruskal-Wallis test for non-parametric samples) showed that none of the Pleistocene pit samples is statistically distinct from the rest, indicating complete stasis from 35 ka to 9 ka. The sole exception was the Pit 13 sample of dire wolves (16 ka), which was significantly smaller than the rest, but this did not occur in response to climate change. We also performed a time series analysis of the pit samples. None showed directional change; all were either static or showed a random walk. Thus, the data show that birds and mammals at Rancho La Brea show complete stasis and were unresponsive to the major climate change that occurred at 20 ka, consistent with other studies of Pleistocene animals and plants. Most explanations for such
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LACTULOSE IN PREOPERATIVE PREPARATION OF CHILDREN WITH DECOMPENSATED TYPE OF CHRONIC COLON STASIS
Directory of Open Access Journals (Sweden)
I.V. Kirgizov
2009-01-01
Full Text Available This article describes the results of estimation of effectiveness of lactulose (Dupfalac in preoperative preparation of children with decompensated type of chronic colon stasis. Proved, that administration of this medication normalizes such indices of homeostasis as acid-base balance of blood and microbiocenose of colon by 7days. Use of lactulose decreases patient complaints on nausea, vomiting, abdominal pain, weakness in 1.6 times rarely then in group of children using other laxative medications in preoperative preparation.Key words: megacolon syndrome, lactulose, dysbacteriosis, blood acid-base balance.(Voprosy sovremennoi pediatrii — Current Pediatrics. 2009;8(1:68-71
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Pavlov, Alexander A.
2011-01-01
In its motion through the Milky Way galaxy, the solar system encounters an average density (>=330 H atoms/cubic cm) giant molecular cloud (GMC) approximately every 108 years, a dense (approx 2 x 103 H atoms/cubic cm) GMC every approx 109 years and will inevitably encounter them in the future. However, there have been no studies linking such events with severe (snowball) glaciations in Earth history. Here we show that dramatic climate change can be caused by interstellar dust accumulating in Earth's atmosphere during the solar system's immersion into a dense (approx ,2 x 103 H atoms/cubic cm) GMC. The stratospheric dust layer from such interstellar particles could provide enough radiative forcing to trigger the runaway ice-albedo feedback that results in global snowball glaciations. We also demonstrate that more frequent collisions with less dense GMCs could cause moderate ice ages.
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A journey through Earth climates
International Nuclear Information System (INIS)
Ramstein, Gilles; Brunet, Michel
2015-01-01
The author proposes a history of climates all along Earth's history, describes how cold and warm periods have been alternating during these billions of years. He also tries to highlight lessons learned from this long evolution of climate in order to better understand the current global warming. He discusses whether this disruption is unique in Earth's history, and how it threatens our environment and therefore our survival. The chapters describe how Earth could escape a global glaciation, the thermal regulation by greenhouse effect gases in a world without oxygen, the empowerment of oxygen and the first thermal accident, a new oxygenated and warm world, the second accident or how Earth entered and escaped from periods of total glaciation, the possible stabilisation, the succession of deregulations, crisis and extinctions, the slow way down to the cold, the various paleo-indicators during the Quaternary, the high frequency oscillations of climate during the last million of years, and the uncertain projections
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Directory of Open Access Journals (Sweden)
Xiao-Ling Chi
2016-01-01
Full Text Available This study aims to explore a useful noninvasive assessment containing TCM syndrome elements for liver fibrosis in CHB patients. The demographic, clinical, and pathological data were retrospectively collected from 709 CHB patients who had ALT less than 2 times the upper limit of normal from April 2009 to October 2012. Logistical regression and area under receiver-operator curve (AUROC were used to determine the diagnostic performances of simple tests for advanced fibrosis (Scheuer stage, F ≥ 3. Results showed that the most common TCM syndrome element observed in this CHB population was dampness and Qi stagnation, followed by blood stasis, by heat, and less by Qi deficiency and Yin deficiency. The logistical regression analysis identified AST ≥ 35 IU/L, PLT ≤ 161 × 109/L, and TCM syndrome element of blood stasis as the independent risk factors for advanced fibrosis. Therefore, a score model containing these three factors was established and tested. The score model containing blood stasis resulted in a higher AUC (AUC = 0.936 compared with APRI (AUC = 0.731 and FIB-4 (AUC = 0.709. The study suggested that the score model containing TCM syndrome element of blood stasis could be used as a useful diagnostic tool for advanced fibrosis in CHB patients and presented a better performance compared to APRI and FIB-4.
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Explaining stasis: microevolutionary studies in natural populations.
Merilä, J; Sheldon, B C; Kruuk, L E
2001-01-01
Microevolution, defined as a change in the genetic constitution of a population over time, is considered to be of commonplace occurrence in nature. Its ubiquity can be inferred from the observation that quantitative genetic divergence among populations usually exceeds that to be expected due to genetic drift alone, and from numerous observations and experiments consistent with local adaptation. Experimental manipulations in natural populations have provided evidence that rapid evolutionary responses may occur in the wild. However, there are remarkably few cases where direct observations of natural populations have revealed microevolutionary changes occurring, despite the frequent demonstration of additive genetic variation and strong directional selection for particular traits. Those few cases where responses congruent with expectation have been demonstrated are restricted to changes over one generation. In this article we focus on possible explanations as to why heritable traits under apparently strong directional selection often fail to show the expected evolutionary response. To date, few of these explanations for apparent stasis have been amenable to empirical testing. We describe new methods, derived from procedures developed by animal breeding scientists, which can be used to address these explanations, and illustrate the approach with examples from long-term studies of collared flycatchers (Ficedula albicollis) and red deer (Cervus elaphus). Understanding why most intensively studied natural populations do not appear to be evolving is an important challenge for evolutionary biology.
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Liu, Shi-yi; Zhang, Yin-qiang; Liu, Yan-ling; Guo, Peng; Zhou, Chun-mei
2013-11-01
To observe the clinical efficacy of treating chronic hepatitis B liver fibrosis (CHBLF) in different stages by syndrome typing and different activating blood removing stasis methods (ABRSM). Totally 100 CHBLF patients of vital qi deficiency blood stasis syndrome (VQDBSS) treated at the Department of Liver Diseases, Xiyuan Hospital, China Academy of Chinese Medical Sciences from July 2008 to December 2011, were randomly assigned to the treatment group and the control group, 50 in each group. Those in the treatment group were treated by self-formulated decoctions for activating blood nourishing blood (ABNB), activating blood removing stasis (ABRS), and activating blood softening hard mass (ABSHM) according to their stages of disease conditions (mild, moderate, and severe). Those in the control group were treated with Compound Biejia Ruangan Tablet (CBRT). Integrals of Chinese medical syndromes, liver functions [mainly including alanine aminotransferase (ALT), albumin/globulin (A/ G)], ultrasonographic examinations of liver (mainly including echoes of liver, width of spleens, width of portal vein), four indicators of serum hepatic fibrosis [including serum hyaluronic acid (HA), laminin (LN), type IV collagen (IV-C), type III collagen peptide (P-III-P)] were statistically analyzed. The therapeutic course was 6 months for all. Compared with before treatment in the same group, the integrals of Chinese medical syndromes both decreased after treatment in the two groups (P serum biochemical indicators.
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Directory of Open Access Journals (Sweden)
Wang Z
2016-09-01
Full Text Available Zhiqiang Wang,1 Lei Yuan,1 Yongchuan Wang,2 Baizhi Yang,1 Xiaohong Dong,1 Zhaowang Gao3 1Department of Urology, Shouguang Hospital of Traditional Chinese Medicine, Shouguang, 2Department of Urology, Weifang Traditional Chinese Hospital, Weifang, 3Department of Urology, Shandong University of Traditional Chinese Medicine Affiliated Hospital, Shandong, People’s Republic of China Objective: The aim of this meta-analysis and systematic review is to evaluate the safety and efficacy of Chinese herbal medicine (CHM for chronic prostatitis (CP associated with damp-heat and blood-stasis syndromes.Methods: An electronic search of 13 databases up to May 2016 was screened to identify randomized controlled trials comparing the safety and efficacy of CHM for the treatment of CP associated with damp-heat and blood-stasis syndromes. Studies reporting on effective rates, adverse events, National Institutes of Health chronic prostatitis symptom index (NIH-CPSI scores, and symptom index of Chinese medicine for chronic prostatitis (SI-CM scores as outcomes were included in the analysis. Data were analyzed by fixed- or random-effect models using the Review Manager software.Results: Thirteen articles with the modified Jadad score ≥4 were identified. It was found that CHM was superior to placebo in increasing the efficacy (odds ratio: 6.72, 95% confidence interval [CI]: 2.78–9.48, P<0.00001 and reducing the SI-CM scores (standardized mean difference: -1.08, 95% CI: -1.35 to -0.81, P<0.00001. Oral CHMs were significantly more effective than placebo at reducing NIH-CPSI scores, with a mean difference of -1.39 (95% CI: -1.87 to -0.92, P<0.00001. Nevertheless, no significant differences were found between Prostant and placebo (standardized mean difference: -0.23, 95% CI: -0.46 to 0.01, P=0.06. The frequency of adverse events associated with oral CHM was similar to that associated with placebo (risk ratio: 1.36, 95% CI: 0.72–2.55, P=0.34 and less than that
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Oxygen - A Four Billion Year History
DEFF Research Database (Denmark)
Canfield, Donald Eugene
The air we breathe is twenty-one percent oxygen, an amount higher than on any other known world. While we may take our air for granted, Earth was not always an oxygenated planet. How did it become this way? Oxygen is the most current account of the history of atmospheric oxygen on Earth. Donald...... Canfield--one of the world's leading authorities on geochemistry, earth history, and the early oceans--covers this vast history, emphasizing its relationship to the evolution of life and the evolving chemistry of the Earth. With an accessible and colorful first-person narrative, he draws from a variety...... of fields, including geology, paleontology, geochemistry, biochemistry, animal physiology, and microbiology, to explain why our oxygenated Earth became the ideal place for life. Describing which processes, both biological and geological, act to control oxygen levels in the atmosphere, Canfield traces...
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C. Sousa
2016-01-01
[EN] The main objective of the present work is the selection and integration of objectives and methods of education for gender equity within the Life and Earth Sciences’ learning environments in the current portuguese frameworks of middle and high school. My proposal combines inquiry learning-teaching methods with the aim of promoting gender equity, mainly focusing in relevant 20th century women-scientists with a huge contribute to the History of Science.The hands-on and minds-on activities p...
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Population-specific life histories contribute to metapopulation viability
Halsey, Samniqueka J.; Bell, Timothy J.; McEachern, A. Kathryn; Pavlovic, Noel B.
2016-01-01
Restoration efforts can be improved by understanding how variations in life-history traits occur within populations of the same species living in different environments. This can be done by first understanding the demographic responses of natural occurring populations. Population viability analysis continues to be useful to species management and conservation with sensitivity analysis aiding in the understanding of population dynamics. In this study, using life-table response experiments and elasticity analyses, we investigated how population-specific life-history demographic responses contributed to the metapopulation viability of the Federally threatened Pitcher's thistle (Cirsium pitcheri). Specifically, we tested the following hypotheses: (1) Subpopulations occupying different environments within a metapopulation have independent demographic responses and (2) advancing succession results in a shift from a demographic response focused on growth and fecundity to one dominated by stasis. Our results showed that reintroductions had a positive contribution to the metapopulation growth rate as compared to native populations which had a negative contribution. We found no difference in succession on the contribution to metapopulation viability. In addition, we identified distinct population-specific contributions to metapopulation viability and were able to associate specific life-history demographic responses. For example, the positive impact of Miller High Dunes population on the metapopulation growth rate resulted from high growth contributions, whereas increased time of plant in stasis for the State Park Big Blowout population resulted in negative contributions. A greater understanding of how separate populations respond in their corresponding environment may ultimately lead to more effective management strategies aimed at reducing extinction risk. We propose the continued use of sensitivity analyses to evaluate population-specific demographic influences on
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Osteopatía hipertrófica secundaria a metástasis pulmonar de carcinoma mamario
Correa Salgado, Ricardo Andrés; Giraldo Villegas, Juan Carlos
2015-01-01
Propósitos: este artículo pretende reportar los hallazgos de un caso clínico de osteopatía hipertrófica. Tema: la osteopatía hipertrófica es un raro desorden paraneoplásico, asociado con el sobrecrecimiento doloroso del periostio de los huesos largos, normalmente desencadenado por neoplasias primarias o metastásicas de pulmón. Desarrollo: se presenta el caso de un rottweiler, de 12 años, con osteopatía hipertrófica asociada con metástasis pulmonar de un carcinoma mamario. Conclusiones: se com...
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Directory of Open Access Journals (Sweden)
C. Sousa
2016-03-01
Full Text Available The main objective of the present work is the selection and integration of objectives and methods of education for gender equity within the Life and Earth Sciences’ learning environments in the current portuguese frameworks of middle and high school. My proposal combines inquiry learning-teaching methods with the aim of promoting gender equity, mainly focusing in relevant 20th century women-scientists with a huge contribute to the History of Science. The hands-on and minds-on activities proposed for high scholl students of Life and Earth Sciences onstitute a learnig environment enriched in features of science by focusing on the work of two scientists: Lynn Margulis (1938-2011 and her endosymbiosis theory of the origin of life on Earth and Inge Leehman (1888-1993 responsible for a breakthrough regarding the internal structure of Earth, by caracterizing a discontinuity within the nucleus, contributing to the current geophysical model. For middle scholl students the learning environment includes Inge Leehman and Mary Tharp (1920-2006 and her first world map of the ocean floor. My strategy includes features of science, such as: theory-laden nature of scientific knowledge, models, values and socio-scientific issues, technology contributes to science and feminism. In conclusion, I consider that this study may constitute an example to facilitate the implementation, by other teachers, of active inquiry strategies focused on features of science within a framework of social responsibility of science, as well as the basis for future research.
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Isotopes and the early evolution of the earth
International Nuclear Information System (INIS)
Russell, R.D.
1980-01-01
The observed isotopic ratios of lead, strontium, neodymium, helium, and argon contain information about the chemical abundances of selected parent and daughter elements in the outer parts of the Earth. By necessity, we observe these isotopic ratios at the Earth's surface, which is a small, highly evolved part of the Earth. The studies of such isotopic ratios permit inferences to be made about interactions between this crust and the upper mantle. Helium has been especially valuable for demonstrating that primordial materials are still being outgassed from the earth. Models based on the observed argon isotopic ratios have lead to contradictory conclusions about the existence of an early period of extensive outgassing of the Earth. Lead has been a particularly interesting element because the ratio of the parents, 235 U/ 238 U, was very different in the Earth's early history than it is now. Therefore there is the potential for determining constraints on the early history of the Earth. A number of recently published papers offering lead isotope interpretations that reflect on the Earth's early history are reviewed, with special reference to models that are based upon uni-directional and bi-directional exchange between a protocrust and a residual mantle. Geochemical parameters for uranium, thorium and lead can be inferred for two evolving systems, as well as rate constants for differentiation. The principal conclusions are that the differentiation process extended beyond the first quarter of the Earth's history, and that it is possible to reproduce exactly the apparent oceanic basalt isochron by a simple two-reservoir model. In particular, such a model can explain quantitatively the observed lead-207 deficiency in the oceanic basalts
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International Nuclear Information System (INIS)
Marx, G.
1986-01-01
The article on nuclear history is contained in a booklet on the Revised Nuffield Advanced Physics Course. The author shows how the difficult decisions about energy supplies at the end of the twentieth century can be seen as a consequence of the history and evolution of the Universe and of life, and mankind's activities on earth. The topics discussed include:-the origin of the Universe, formation of light elements, formation of carbon and oxygen, supernovae and nuclear equilibrium, formation of planets, development of life on earth, mankind and the use of fuels, and the nuclear valley. (UK)
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Hedin, M C
2001-02-01
The spider genus Hypochilus is currently restricted to cool, moist microhabitats in three widely separated montane regions of North America, providing an opportunity to study both deep (i.e., continental level) and shallow (within montane region) biogeographic history. Members of the genus also retain many plesiomorphic morphological characteristics, inviting the study of comparative rates of morphological evolution. In this paper, Hypochilus phylogeny and associated evolutionary problems are addressed using both new molecular (28S nDNA and CO1 mtDNA) and previously published (K. M. Catley, 1994, Am. Mus. Nov. 3088, 1-27) morphological data. Although the molecular data provide limited resolution of root placement within Hypochilus, most analyses are at least consistent with morphology-supported montane relationships of (Rockies (California, Appalachian)). The monophyly of Hypochilus species distributed in the California mountains is ambiguous, with several analyses indicating that this fauna may be paraphyletic with respect to a monophyletic Appalachian lineage. The montane regions differ in consistent ways in depths of both mitochondrial and nuclear phylogenetic divergence. Molecular clock analyses, in combination with arthropod-based mtDNA rate calibrations, suggest that the regional faunas are of different ages and that speciation in all faunas likely occurred prior to the Pleistocene. Limited intraspecific sampling reveals extraordinarily high levels of mtDNA cytochrome oxidase sequence divergence. These extreme divergences are most consistent with morphological stasis at the species level, despite preliminary evidence that Hypochilus taxa are characterized by fragmented population structures. Copyright 2001 Academic Press.
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Leszek,Tomasz Ros
2004-01-01
Muchos autores demuestran sobre los ejemplos de sus pacientes que Sertralina es una medicación más eficaz y mejor tolerada en el tratamiento de la "depresión mayor" en el curso de las enfermedades de cáncer con metástasis. Presentamos el caso de una entrenadora de gimnasia.
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Detección de micrometástasis de carcinoma de colon en ganglios linfáticos
Directory of Open Access Journals (Sweden)
A. Roma
2003-10-01
Full Text Available En el carcinoma colorrectal la diseminación a los ganglios linfáticos es un factor pronóstico reconocido. La presencia de ganglios linfáticos con micrometástasis en muchos casos no puede ser detectada por técnicas rutinarias. Se estudiaron prospectivamente 162 ganglios linfáticos de 30 pacientes con carcinoma de colon, los cuales según los resultados de las técnicas rutinarias fueron clasificados como Dukes A (2, Dukes B (19 y Dukes C (9. Un paciente con enfermedad colónica benigna se uso como control negativo. Todos los ganglios se seccionaron en mitades, una de las cuales se almacenó en nitrógeno líquido para su ulterior estudio por técnicas de biología molecular, mediante la expresión del antígeno carcinoembrionario (CEA. La otra mitad fue fijada en formaldehído e incluida en parafina para su estudio anatomopatológico e inmunohistoquímico. Del total de los casos se detectó un aumento del 50% de la sensibilidad en la detección de micrometástasis mediante la reacción en cadena de la polimerasa con transcriptasa reversa (RT-PCR para los Dukes A-B y se detectó la expresión de dicho antígeno en el total de los casos Dukes C. Estos resultados evidencian una mayor sensibilidad en la detección de micrometástasis utilizando RT-PCR en comparación con las técnicas rutinarias, incluyendo la inmunohistoquímica.Dissemination of lymph nodes is a known prognostic factor in colorectal carcinoma. Micrometastases in lymph nodes can be missed when studied by routine techniques. We analyzed 162 lymph nodes from 30 patients with colonic carcinoma and using routine techniques, they were classified as follows: two Dukes A; nineteen Dukes B; and nine Dukes C. A patient with benign colon disease served as negative control. Lymph nodes were all sectioned in halves, with one of the halves stored in liquid nitrogen for molecular biology examination by carcinoembryonic antigen expression. The other formalin-fixed and paraffin embedded
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Selection on skewed characters and the paradox of stasis.
Bonamour, Suzanne; Teplitsky, Céline; Charmantier, Anne; Crochet, Pierre-André; Chevin, Luis-Miguel
2017-11-01
Observed phenotypic responses to selection in the wild often differ from predictions based on measurements of selection and genetic variance. An overlooked hypothesis to explain this paradox of stasis is that a skewed phenotypic distribution affects natural selection and evolution. We show through mathematical modeling that, when a trait selected for an optimum phenotype has a skewed distribution, directional selection is detected even at evolutionary equilibrium, where it causes no change in the mean phenotype. When environmental effects are skewed, Lande and Arnold's (1983) directional gradient is in the direction opposite to the skew. In contrast, skewed breeding values can displace the mean phenotype from the optimum, causing directional selection in the direction of the skew. These effects can be partitioned out using alternative selection estimates based on average derivatives of individual relative fitness, or additive genetic covariances between relative fitness and trait (Robertson-Price identity). We assess the validity of these predictions using simulations of selection estimation under moderate sample sizes. Ecologically relevant traits may commonly have skewed distributions, as we here exemplify with avian laying date - repeatedly described as more evolutionarily stable than expected - so this skewness should be accounted for when investigating evolutionary dynamics in the wild. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.
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Czech Academy of Sciences Publication Activity Database
Mottequin, B.; Slavík, Ladislav; Königshof, P.
2017-01-01
Roč. 97, 3 SI (2017), s. 367-374 ISSN 1867-1594 Institutional support: RVO:67985831 Keywords : editorial material * Earth's history * biodiversity * climate changes Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Paleontology Impact factor: 1.278, year: 2016
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Metástasis hipofisaria de carcinoma de mama debutando como diabetes insípida
Directory of Open Access Journals (Sweden)
Ana Arévalo
2012-03-01
Full Text Available Los tumores metastáticos que afectan a la glándula hipofisaria son hallazgos pocos comunes, presentándose en cerca del 1% de las cirugías hipofisarias. Los autores presentan el caso de una paciente mujer de 46 años que debuta con síntomas de diabetes insípida. Había sido tratada 3 años antes por un carcinoma ductal infiltrante de la mama derecha. Las imágenes de resonancia magnética cerebral mostraron una masa en la silla turca con extensión supraselar. La paciente fue sometida a resección tumoral vía transesfenoidal que demostró metástasis de carcinoma de mama.
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Directory of Open Access Journals (Sweden)
J. Ferreras Granado
2007-10-01
Full Text Available Los tumores malignos de la cavidad oral y mandíbula representan aproximadamente un 5% de todas las neoplasias malignas del cuerpo, y sólo entre el 1 y el 4% son consideradas como metástasis. Tienen su localización más frecuente a nivel de la mandíbula (80%, fundamentalmente en la región molar. Las metástasis mandibulares, cuando aparecen, suelen tener su origen en tumores primarios que asientan en la mama, pulmón, riñón, tiroides, intestinos y próstata; y con menor frecuencia en el estómago, testículos y vesícula biliar. Suelen afectar a pacientes de edad avanzada (4ª-7ª décadas de la vida sin predilección por el sexo. El tratamiento en general es paliativo y pasa por el uso de la radioterapia, quimioterapia y hormonoterapia, reservando la cirugía para casos aislados. Describimos un caso de metástasis mandibular en un paciente adulto como primera manifestación clínica de un adenocarcinoma gástrico.Malignant tumors of the mouth and jaws represents approximately 5% of all malignant neoplasms in the body, and only 1-4% are considered to be metastatic. They are most frequently located in the mandible (80%, fundamentally in the molar region. Metastases to the jaws are usually from breast, lung, kidney, thyroid gland, intestines, and prostate gland; and less frequently from stomach, testes, and bladder. They are more frequent in elderly patients (between 4th and 7th decades with no gender differences. Treatment is usually palliative and based on the use of radiotherapy, chemotherapy andhormonal therapy. Surgery is only used in selected cases. A case of mandibular metastases as first sign of malignant disease of gastric adenocarcinoma is reported.
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The Earth Through Time: Implications for Searching for Habitability and Life on Exoplanets
Pilcher, Carl B.
2016-01-01
The Earth has been both a habitable and inhabited planet for around 4 billion years, yet distant observers studying Earth at different epochs in our history would have detected substantially different and probably varying conditions. Understanding Earth's history thus has much to tell us about how to interpret observations of potentially habitable exoplanets. In this talk I will review the history of life on Earth, from the earliest microbial biosphere living under a relatively methane-rich atmosphere to the modern world of animals, plants, and atmospheric oxygen, with a focus on how observable conditions on Earth changed as the planet and its biosphere evolved. I'll discuss the implications of this history for assessing the habitability of-or presence of life on-planets around other stars.
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Chromosomal stasis in distinct families of marine Percomorpharia from South Atlantic.
Paim, Fabilene Gomes; Almeida, Leandro Aragão da Hora; Affonso, Paulo Roberto Antunes de Mello; Sobrinho-Scudeler, Patrícia Elda; Oliveira, Claudio; Diniz, Débora
2017-01-01
The weakness of physical barriers in the marine environment and the dispersal potential of fish populations have been invoked as explanations of the apparent karyotype stasis of marine Percomorpha, but several taxa remain poorly studied cytogenetically. To increase the chromosomal data in this fish group, we analyzed cytogenetically three widespread Atlantic species from distinct families: Chaetodipterus faber Broussonet, 1782 (Ephippidae), Lutjanus synagris Linnaeus, 1758 (Lutjanidae) and Rypticus randalli Courtenay, 1967 (Serranidae). The three species shared a karyotype composed of 2n=48 acrocentric chromosomes, single nucleolus organizer regions (NORs) and reduced amounts of centromeric heterochromatin. A single NOR-bearing pair was identified in all species by physical mapping of 18S rDNA while non-syntenic 5S rRNA genes were located at centromeric region of a single pair. The similar karyotypic macrostructure observed in unrelated groups of Percomorpharia reinforces the conservative karyoevolution of marine teleosteans. Nonetheless, the species could be differentiated based on the pair bearing ribosomal cistrons, revealing the importance of microstructural analyses in species with symmetric and stable karyotypes.
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Early Earth(s) Across Time and Space
Mojzsis, S.
2014-04-01
The geochemical and cosmochemical record of our solar system is the baseline for exploring the question: "when could life appear on a world similar to our own?" Data arising from direct analysis of the oldest terrestrial rocks and minerals from the first 500 Myr of Earth history - termed the Hadean Eon - inform us about the timing for the establishment of a habitable silicate world. Liquid water is the key medium for life. The origin of water, and its interaction with the crust as revealed in the geologic record, guides our exploration for a cosmochemically Earth-like planets. From the time of primary planetary accretion to the start of the continuous rock record on Earth at ca. 3850 million years ago, our planet experienced a waning bolide flux that partially or entirely wiped out surface rocks, vaporized oceans, and created transient serpentinizing atmospheres. Arguably, "Early Earths" across the galaxy may start off as ice planets due to feeble insolation from their young stars, occasionally punctuated by steam atmospheres generated by cataclysmic impacts. Alternatively, early global environments conducive to life spanned from a benign surface zone to deep into crustal rocks and sediments. In some scenarios, nascent biospheres benefit from the exogenous delivery of essential bio-elements via leftovers of accretion, and the subsequent establishment of planetary-scale hydrothermal systems. If what is now known about the early dynamical regime of the Earth serves as any measure of the potential habitability of worlds across space and time, several key boundary conditions emerge. These are: (i) availability and long-term stability of liquid water; (ii) presence of energy resources; (iii) accessibility of organic raw materials; (iv) adequate inventory of radioisotopes to drive internal heating; (v) gross compositional parameters such as mantle/core mass ratio, and (vi) P-T conditions at or near the surface suitable for sustaining biological activity. Life could
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THE PRECAMBRIAN HISTORY OF THE ORIGIN AND EVOLUTION OF THE SOLAR SYSTEM AND EARTH. PART 1
Directory of Open Access Journals (Sweden)
M. I. Kuz’min
2014-01-01
Full Text Available The paper provides a review of early stages of development the Solar System and the geological history of Earth with reference to the latest data on the origin of the Solar System and the formation of the first continental rocks and results of studies of zircon, the oldest mineral so far dated on Earth. The formation of the Solar System from a gas-and-dust nebula is estimated to have begun 4.568 billion years ago. Ice was formed 1.5 million years later; it concentrated at the periphery of the system and served as the material for the largest planets, Jupiter and Saturn. In the central areas of the system, asteroids with diameters of about 10 km were formed. Their small bodies were composed of the basic material of the solar nebula, as evidenced by carbonaceous chondrite, CI, which composition is similar to the composition of the Sun, with the exception of hydrogen, helium, and volatile components that served as the main material for peripheral planets of the Solar System. Due to collision and partial merger of such small bodies, the formation of embryos of the terrestrial planets was initiated. Gravity made such embryos to cluster into larger bodies. After 7 million years, large asteroids and planet Mars were formed. It took 11 million years to form Planet Earth with a mass of 63 %, and 30 million years to form 93 % of its mass. Almost from the beginning of the formation of the Earth, short-lived radionuclides, 26Al and 60Fe, caused warming up of the small planetary bodies which led to the formation of their cores. During the initial stages, small magma reservoirs were formed, and molten iron particles gathered in the centres of the planetary bodies. As suggested by the ratio of 182W/184W, the major part of the core was formed within 20 million years, while its full mass accumulated completely within the next 50 million years. In 30–40 million years after the creation of the Solar System, the Earth collided with a cosmic body which mass was
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International Nuclear Information System (INIS)
Zhang Qinghua; Guo Yiqin; Li Zhuanfu
1990-01-01
In this study 100 cases of C. O. P. D were classified according to dialectical method of traditional Chinese Medicine. By infusion lung imaging it was shown that 76 cases were abnormal in blood supply in which the category of 'fei xin qi xu' ('weak in heart and lung breath') got the first place and followed by the category of II order 'fei qi xu' ('weak in lung breath'). It was considered that the change in lung infusion imagings were the evidence of 'fei xu zheng' ('weak-lunged symptom') 'xin xue yu zu' ('stasis of heart blood') and might be used to guide the treatment and to observe the efficiency of 'huo xue hua yu' ('invigorating blood circulation and eliminating stasis') therapy
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The origin of the moon and the early history of the earth - a chemical model. Part 2: The earth
International Nuclear Information System (INIS)
O'Neill, H.St.C.
1991-01-01
The geochemical implications for the earth of a giant impact model for the origin of the earth-moon system are discussed, using a mass balance between three components: the proto-earth, the Impactor, and a late veneer. It is argued that the proto-earth accretes from material resembling a high temperature condensate from the solar nebula. Core formation takes place under very reducing conditions, resulting in the mantle of the proto-earth being completely stripped of all elements more siderophile than Fe, and partly depleted in the barely siderophile elements V, Cr, and perhaps Si. The Impactor then collides with the proto-earth, causing vaporisation of both the Impactor and a substantial portion of the earth's mantle. Most of this material recondenses to the earth, but some forms the moon. The Impactor adds most of the complement of the siderophile elements of the present mantle in an oxidized form. The oxidation state of the mantle is set near to its present, oxidized level. Finally, the addition of a late veneer, of composition similar to that of the H-group ordinary chondrites, accounts for the complement of the highly siderophile elements of the present mantle. The model accounts at least semi-quantitatively for the siderophile element abundances of the present mantle. Implications for the composition of the earth's core are discussed; the model predicts that neither S, O, nor Si should be present in sufficient quantities to provide the required light element in the core, whose identity, therefore, remains enigmatic
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Liu, Hong; Peng, Yao-Yao; Liang, Feng-Yin; Chen, Si; Li, Pei-Bo; Peng, Wei; Liu, Zhong-Zheng; Xie, Cheng-Shi; Long, Chao-Feng; Su, Wei-Wei
2014-01-02
NaoShuanTong capsule (NSTC), an oral traditional Chinese medicine formula, is composed of Pollen Typhae , Radix Paeoniae Rubra , Rhizoma Gastrodiae , Radix Rhapontici and Radix Curcumae . It has been widely used to treat ischemic stroke in clinic for many years in China. In addition to neuronal apoptosis, haemorheology and cerebral energy metabolism disorders also play an important role in the pathogenesis and development of ischemic stroke. The present study was designed to evaluate the in vivo protective effects of NSTC on haemorheology and cerebral energy metabolism disorders in rats with blood stasis. Sixty specific pathogen-free sprague-dawley rats, male only, were randomly divided into six groups (control group, model group, aspirin (100 mg/kg/d) group, NSTC low-dose (400 mg/kg/d) group, NSTC intermediate-dose (800 mg/kg/d) group, NSTC high-dose (1600 mg/kg/d) group) with 10 animals in each. The rats except those in the control group were placed in ice-cold water (0-4 °C) for 5 min during the time interval (4 h) of two adrenaline hydrochloride injections (0.8 mg/kg) to induce blood stasis. After treatment, whole blood viscosity at three shear rates, plasma viscosity and erythrocyte sedimentation rate significantly decreased in NSTC intermediate- and high-dose groups; erythrocyte aggregation index and red corpuscle electrophoresis index significantly decreased in all the three dose NSTC groups. Moreover, treatment with high-dose NSTC could significantly improve Na + -K + adenosine triphosphatase (ATPase) and Ca 2+ ATPase activity, as well as lower lactic acid level in brain tissues. These results demonstrated the protective effects of NSTC on haemorheology and cerebral energy metabolism disorders, which may provide scientific information for the further understanding of mechanism(s) of NSTC as a clinical treatment for ischemic stroke. Furthermore, the protective effects of activating blood circulation as observed in this study might create valuable
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Biological extinction in earth history
Raup, D. M.
1986-01-01
Virtually all plant and animal species that have ever lived on the earth are extinct. For this reason alone, extinction must play an important role in the evolution of life. The five largest mass extinctions of the past 600 million years are of greatest interest, but there is also a spectrum of smaller events, many of which indicate biological systems in profound stress. Extinction may be episodic at all scales, with relatively long periods of stability alternating with short-lived extinction events. Most extinction episodes are biologically selective, and further analysis of the victims and survivors offers the greatest chance of deducing the proximal causes of extinction. A drop in sea level and climatic change are most frequently invoked to explain mass extinctions, but new theories of collisions with extraterrestrial bodies are gaining favor. Extinction may be constructive in a Darwinian sense or it may only perturb the system by eliminating those organisms that happen to be susceptible to geologically rare stresses.
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Biological Extinction in Earth History
Raup, David M.
1986-03-01
Virtually all plant and animal species that have ever lived on the earth are extinct. For this reason alone, extinction must play an important role in the evolution of life. The five largest mass extinctions of the past 600 million years are of greatest interest, but there is also a spectrum of smaller events, many of which indicate biological systems in profound stress. Extinction may be episodic at all scales, with relatively long periods of stability alternating with short-lived extinction events. Most extinction episodes are biologically selective, and further analysis of the victims and survivors offers the greatest chance of deducing the proximal causes of extinction. A drop in sea level and climatic change are most frequently invoked to explain mass extinctions, but new theories of collisions with extraterrestrial bodies are gaining favor. Extinction may be constructive in a Darwinian sense or it may only perturb the system by eliminating those organisms that happen to be susceptible to geologically rare stresses.
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Directory of Open Access Journals (Sweden)
Xiao-Sha Zhang
2017-11-01
Full Text Available Objective: To observe the influence of promoting blood circulation to remove blood stasis combined with laparoscopy on serum MCP-1, RANTES, oxidative stress and hormones in infertile patients with endometriosis. Methods: A total of 60 infertile patients with endometriosis were randomly divided into observation group (30 cases and control group (30 cases. Observation group: promoting blood circulation to remove blood stasis combined with laparoscopy; control group: patients were treated only by laparoscopy. Recording and comparing the levels of MCP-1, RANTES, oxidative stress and hormones before and after treatment. Results: (1 Before treatment, there was no statistically significant difference in the serum MCP-1, RANTES, AOPP, MDA, SOD, levels between the two groups. After treatment, compared with the same group before treatment, the serum RANTES, AOPP, MDA levels of the two groups were significantly lower, the serum SOD level of the two groups were significantly higher, and those levels of observation group were significantly better than the control group, there was significant difference between the two groups. (2 Before treatment, there was no statistically significant difference in the serum FSH, LH, E2, P, PRL levels between the two groups. After treatment, compared with the same group before treatment, the serum FSH, LH, P, PRL levels of the two groups were significantly higher, the serum E2 level of the two groups were significantly lower, and those levels of observation group were significantly better than the control group, there was significant difference between the two groups. Conclusion: Promoting blood circulation to remove blood stasis combined with laparoscopy for infertile patients with endometriosis can reduce the levels of serum MCP-1, RANTES, oxidative stress, hormones and be beneficial to protect their uterine function.
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The International Big History Association
Duffy, Michael; Duffy, D'Neil
2013-01-01
IBHA, the International Big History Association, was organized in 2010 and "promotes the unified, interdisciplinary study and teaching of history of the Cosmos, Earth, Life, and Humanity." This is the vision that Montessori embraced long before the discoveries of modern science fleshed out the story of the evolving universe. "Big…
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Radiation chemistry and origins of life on earth
International Nuclear Information System (INIS)
Zagorski, Z. P.
2001-01-01
The role of radiation chemical processes in prebiotic time of earth history and their influence on arise of organic life on Earth has been discussed. The formation of chiral compounds in prebiotic s oup' and its further evolution for creation of bioorganic molecules was also presented and discussed as an alternative of existing hypothesis of cosmic origin of biologic life in the Earth
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Venus tectonics: another Earth or another Mars
International Nuclear Information System (INIS)
McGill, G.E.
1979-01-01
The presence of presumably primordial large craters has led to the suggestion that Venus may have a thick lithosphere like that of Mars despite its similarities to Earth in size and density. However, crust and upper mantle temperatures on Venus are very likely higher than on Earth so that a dry Venus could have a lithosphere with a thickness similar to that of Earth. If a trace of volatiles is present in the mantle, the lithosphere of Venus could be thinner. Due to the absence of liquid water, erosion and deposition will be much slower on Venus than on Earth, favoring retention of primordial cratered surfaces on portions of the crust that have not been destroyed or buried by tectonic and volcanic activity. Geochemical models of solar system origin and petrological considerations suggest that K is about as abundant in Venus as in Earth. The abundance of 40 Ar in the atmosphere of Venus lies somewhere between the Earth value and one-tenth of the Earth value. Because erosional liberation of 40 Ar on Venus will be relatively inefficient, this range for 40 Ar abundance at least permits an active tectonic history, and if the 40 Ar abundance is towards the high end of the range, it may well require an active tectonic history. Thus we are not constrained to a Mars-like model of Venus tectonics by craters and possible mantle dryness; an Earth-like model is equally probable
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Age of the earth and solar system
International Nuclear Information System (INIS)
Manhes, G.
1977-01-01
The history of chemical element formation and radiochronology is given. The study of Pb isotope composition evolution enables to estimate the age of the earth. A series of galena of known ages was measured. By means of a model, it is possible to determine the initial isotope composition of Pb on the earth and the age of the earth. On the other hand, the analysis of stony meteorites provides a Pb isotope composition higher than the earth value. A comparison of the data shows a fundamental transition at 4.55 10 9 years [fr
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A review of noble gas geochemistry in relation to early Earth history
Kurz, M. D.
1985-01-01
One of the most fundamental noble gas constraints on early Earth history is derived from isotopic differences in (129)Xe/(130)Xe between various terrestrial materials. The short half life (17 m.y.) of extinct (129I, parent of (129)Xe, means that these differences must have been produced within the first 100 m.y. after terrestrial accretion. The identification of large anomalies in (129)Xe/(130)Xe in mid ocean ridge basalts (MORB), with respect to atmospheric xenon, suggests that the atmosphere and upper mantle have remained separate since that time. This alone is a very strong argument for early catastrophic degassing, which would be consistent with an early fractionation resulting in core formation. However, noble gas isotopic systematics of oceanic basalts show that the mantle cannot necessarily be regarded as a homogeneous system, since there are significant variations in (3)He/(4)He, (40)Ar/(36)Ar, and (129)Xe/(130)Xe. Therefore, the early degassing cannot be considered to have acted on the whole mantle. The specific mechanisms of degassing, in particular the thickness and growth of the early crust, is an important variable in understanding present day noble gas inventories. Another constraint can be obtained from rocks that are thought to be derived from near the lithosphere asthenosphere boundary: ultramafic xenoliths.
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Terrestrial xenon isotope constraints on the early history of the earth
International Nuclear Information System (INIS)
Ozima, M.; Igarashi, G.; Podosek, F.A.
1985-01-01
Comparison between 129 I-radiogenic 129 Xe and 244 Pu-fissiogenic 136 Xe components in terrestrial xenon suggests that the Earth's inner region accreted a few tens of millions of years earlier than the outer region from which the atmosphere evolved. The results also indicate that there has been no substantial mixing of the two regions since the Earth's accretion. (author)
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Reducing greenhouses and the temperature history of Earth and Mars
International Nuclear Information System (INIS)
Sagan, C.
1977-01-01
The modern theory of stellar evolution implies that the Sun has increased in brightness by several tens per cent over geological time. Were all other global parameters held constant, this would imply that the mean temperature of the Earth was below the freezing point of seawater about 2 x 10 9 yr ago. There is, however, excellent geological and palaeontological evidence that there were extensive bodies of liquid water on the Earth between 3 and 4 x 10 9 yr ago. A possible solution to this puzzle is that the Earth's primitive atmosphere contained small quantities of NH 3 and other reducing gases which significantly enhanced the global 'greenhouse' effect. Cosmochemical considerations point strongly to a higher abundance of reduced constituents in the primitive than in the contemporary terrestrial atmosphere; and reduced atmospheric components such as NH 3 and CH 4 are required to understand the accumulation of prebiological organic compounds necessary for the origin of life between 3 and 4 x 10 9 yr ago. Similar arguments may apply to Mars. (author)
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Reducing greenhouses and the temperature history of Earth and Mars
Energy Technology Data Exchange (ETDEWEB)
Sagan, C [Cornell Univ., Ithaca, N.Y. (USA). Lab. for Planetary Studies
1977-09-15
The modern theory of stellar evolution implies that the Sun has increased in brightness by several tens per cent over geological time. Were all other global parameters held constant, this would imply that the mean temperature of the Earth was below the freezing point of seawater about 2 x 10/sup 9/ yr ago. There is, however, excellent geological and palaeontological evidence that there were extensive bodies of liquid water on the Earth between 3 and 4 x 10/sup 9/ yr ago. A possible solution to this puzzle is that the Earth's primitive atmosphere contained small quantities of NH/sub 3/ and other reducing gases which significantly enhanced the global 'greenhouse' effect. Cosmochemical considerations point strongly to a higher abundance of reduced constituents in the primitive than in the contemporary terrestrial atmosphere; and reduced atmospheric components such as NH/sub 3/ and CH/sub 4/ are required to understand the accumulation of prebiological organic compounds necessary for the origin of life between 3 and 4 x 10/sup 9/ yr ago. Similar arguments may apply to Mars.
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Directory of Open Access Journals (Sweden)
Mariantonia Lemos
2015-05-01
Full Text Available El vínculo de apego ha mostrado ser un factor de vulnerabilidad para las enfermedades crónicas. El presente artículo busca clarificar esta relación mediante la teoría de la alóstasis. La teoría de la alóstasis hace referencia a la regulación de los procesos fisiológicos corporales complejos en el tiempo mediante una respuesta sistémica que mantiene la estabilidad fisiológica cuando se confronta la persona con cambios o retos. Los apegos inseguros confrontan a los niños desde sus primeros años con eventos estresantes, al no brindar al niño la seguridad sentida, finalidad fundamental del apego. De esta forma los apegos inseguros podrían tener impacto en la calibración del sistema de estrés en la edad temprana y serían factores de aumento de la carga alostática mediante mayores eventos vitales estresantes que las personas con apego seguro, una valoración cognitiva de amenaza que lleva al desarrollo de la hipervigilancia y el impacto en los sistemas de regulación del estrés en el cuerpo.
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Predicting loss of evolutionary history: Where are we?
Veron, Simon; Davies, T Jonathan; Cadotte, Marc W; Clergeau, Philippe; Pavoine, Sandrine
2017-02-01
The Earth's evolutionary history is threatened by species loss in the current sixth mass extinction event in Earth's history. Such extinction events not only eliminate species but also their unique evolutionary histories. Here we review the expected loss of Earth's evolutionary history quantified by phylogenetic diversity (PD) and evolutionary distinctiveness (ED) at risk. Due to the general paucity of data, global evolutionary history losses have been predicted for only a few groups, such as mammals, birds, amphibians, plants, corals and fishes. Among these groups, there is now empirical support that extinction threats are clustered on the phylogeny; however this is not always a sufficient condition to cause higher loss of phylogenetic diversity in comparison to a scenario of random extinctions. Extinctions of the most evolutionarily distinct species and the shape of phylogenetic trees are additional factors that can elevate losses of evolutionary history. Consequently, impacts of species extinctions differ among groups and regions, and even if global losses are low within large groups, losses can be high among subgroups or within some regions. Further, we show that PD and ED are poorly protected by current conservation practices. While evolutionary history can be indirectly protected by current conservation schemes, optimizing its preservation requires integrating phylogenetic indices with those that capture rarity and extinction risk. Measures based on PD and ED could bring solutions to conservation issues, however they are still rarely used in practice, probably because the reasons to protect evolutionary history are not clear for practitioners or due to a lack of data. However, important advances have been made in the availability of phylogenetic trees and methods for their construction, as well as assessments of extinction risk. Some challenges remain, and looking forward, research should prioritize the assessment of expected PD and ED loss for more taxonomic
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Energy Technology Data Exchange (ETDEWEB)
Ueda, M
1960-01-01
The thermodynamics of the Earth are described, including terrestrial heat flow, internal temperatures and thermal history. The value of the geothermal gradient has been considered to be 3/sup 0/C/100 m but measured values are slightly different. The values of terrestrial heat flow are relatively constant and are calculated be about 2.3 x 10 to the minus 6 cal/cm/sup 2/ sec (2.3 HFU). The Earth's internal temperature can be calculated from the adiabatic temperature gradient of adiabatic expansion. Using Simon's equation No. 9, a value of 2100-2500/sup 0/C is obtained, this is much lower than it was previously thought to be. The value of 2.3 HFU can easily be obtained from this internal temperature figure.
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Giant Impacts on Earth-Like Worlds
Kohler, Susanna
2016-05-01
Earth has experienced a large number of impacts, from the cratering events that may have caused mass extinctions to the enormous impact believed to have formed the Moon. A new study examines whether our planets impact history is typical for Earth-like worlds.N-Body ChallengesTimeline placing the authors simulations in context of the history of our solar system (click for a closer look). [Quintana et al. 2016]The final stages of terrestrial planet formation are thought to be dominated by giant impacts of bodies in the protoplanetary disk. During this stage, protoplanets smash into one another and accrete, greatly influencing the growth, composition, and habitability of the final planets.There are two major challenges when simulating this N-body planet formation. The first is fragmentation: since computational time scales as N^2, simulating lots of bodies that split into many more bodies is very computationally intensive. For this reason, fragmentation is usually ignored; simulations instead assume perfect accretion during collisions.Total number of bodies remaining within the authors simulations over time, with fragmentation included (grey) and ignored (red). Both simulations result in the same final number of bodies, but the ones that include fragmentation take more time to reach that final number. [Quintana et al. 2016]The second challengeis that many-body systems are chaotic, which means its necessary to do a large number of simulations to make statistical statements about outcomes.Adding FragmentationA team of scientists led by Elisa Quintana (NASA NPP Senior Fellow at the Ames Research Center) has recently pushed at these challenges by modeling inner-planet formation using a code that does include fragmentation. The team ran 140 simulations with and 140 without the effects of fragmentation using similar initial conditions to understand how including fragmentation affects the outcome.Quintana and collaborators then used the fragmentation-inclusive simulations to
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Single grains, thermal histories, and the 40Ar/39Ar method
International Nuclear Information System (INIS)
Wright, Norrie
1989-01-01
A key part in unraveling the history of the physical evolution of the earth is knowledge of the earth's thermal history. 40 Ar/ 39 Ar step heating of mineral samples provides a means of defining a local thermal history. to do this accurately the challenge is to extract meaningful diffusion parameters from a mineral's Arrhenius plot. In the case of biotite single grains, where the laboratory release of argon is a complex process, this can be a difficult task. (12 refs., 5 figs.)
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Expanding Earth and declining gravity: a chapter in the recent history of geophysics
Kragh, H.
2015-05-01
Although speculative ideas of an expanding Earth can be found before World War II, it was only in the 1950s and 1960s that the theory attracted serious attention among a minority of earth scientists. While some of the proponents of the expanding Earth adopted an empiricist attitude by disregarding the physical cause of the assumed expansion, others argued that the cause, either fully or in part, was of cosmological origin. They referred to the possibility that the gravitational constant was slowly decreasing in time, as first suggested by P. Dirac in 1937. As a result of a stronger gravitation in the past, the ancient Earth would have been smaller than today. The gravitational argument for an expanding Earth was proposed by P. Jordan and L. Egyed in the 1950s and during the next 2 decades it was discussed by several physicists, astronomers and earth scientists. Among those who for a period felt attracted by "gravitational expansionism" were A. Holmes, J. Tuzo Wilson and F. Hoyle. The paper examines the idea of a varying gravitational constant and its impact on geophysics in the period from about 1955 to the mid-1970s.
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Schmitt-Ney, M; Happ, B; Hofer, P; Hynes, N E; Groner, B
1992-12-01
The mammary gland-specific nuclear factor (MGF) is a crucial contributor to the regulation of transcription from the beta-casein gene promoter. The beta-casein gene encodes a major milk protein, which is expressed in mammary epithelial cells during lactation and can be induced by lactogenic hormones in the clonal mammary epithelial cell line HC11. We have investigated the specific DNA-binding activity of MGF in mammary epithelial cells in vivo and in vitro. Comparison of MGF in HC11 cells and mammary gland cells from lactating mice revealed molecules with identical DNA-binding properties. Bandshift and UV cross-linking experiments indicated that MGF in HC11 cells has a higher mol wt than MGF found in mice. Little MGF activity was detected in nuclear extracts from HC11 cells cultured in the absence of lactogenic hormones. Lactogenic hormone treatment of HC11 cells led to a strong induction of MGF activity. The induction of MGF activity as well as utilization of the beta-casein promoter were suppressed when epidermal growth factor was present in the tissue culture medium simultaneously with the lactogenic hormones. In lactating animals, MGF activity is regulated by suckling, milk stasis, and systemic hormone signals. The mammary glands from maximally lactating animals, 16 days postpartum, contain drastically reduced MGF activity after removal of the pups for only 8 h. The down-regulation of MGF by pup withdrawal was slower in early lactation, 6 days postpartum. We also investigated the relative contributions of local signals, generated by milk stasis, and systemic hormone signals to the regulation of MGF activity. The access to one row of mammary glands of lactating mothers was denied to the pups for 24 h. High levels of MGF were found in the accessible mammary glands, and intermediate levels of MGF were found in the inaccessible glands of the same mouse. Very low MGF levels were detected when the pups were removed from the dams for 24 h. We conclude that systemic as
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International Nuclear Information System (INIS)
Stosch, H.-G.; Koetz, J.; Herpers, U.
1986-01-01
Three techniques for analyzing rare earth elements (REE) in geological materials are described, i.e. instrumental neutron activation analysis (INAA), neutron activation analysis with pre-irradiation chemical REE separation (PCS-NAA) and radiochemical neutron activation analysis (RNAA). The knowledge of REE concentrationd in eclogites, peridotites and minerals from the earth's lower crust and upper mantle is very useful in constraining their petrogenetic history. (author)
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Estimates of the magnitudes of major marine mass extinctions in earth history
Stanley, Steven M.
2016-10-01
Procedures introduced here make it possible, first, to show that background (piecemeal) extinction is recorded throughout geologic stages and substages (not all extinction has occurred suddenly at the ends of such intervals); second, to separate out background extinction from mass extinction for a major crisis in earth history; and third, to correct for clustering of extinctions when using the rarefaction method to estimate the percentage of species lost in a mass extinction. Also presented here is a method for estimating the magnitude of the Signor-Lipps effect, which is the incorrect assignment of extinctions that occurred during a crisis to an interval preceding the crisis because of the incompleteness of the fossil record. Estimates for the magnitudes of mass extinctions presented here are in most cases lower than those previously published. They indicate that only ˜81% of marine species died out in the great terminal Permian crisis, whereas levels of 90-96% have frequently been quoted in the literature. Calculations of the latter numbers were incorrectly based on combined data for the Middle and Late Permian mass extinctions. About 90 orders and more than 220 families of marine animals survived the terminal Permian crisis, and they embodied an enormous amount of morphological, physiological, and ecological diversity. Life did not nearly disappear at the end of the Permian, as has often been claimed.
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Estimates of the magnitudes of major marine mass extinctions in earth history.
Stanley, Steven M
2016-10-18
Procedures introduced here make it possible, first, to show that background (piecemeal) extinction is recorded throughout geologic stages and substages (not all extinction has occurred suddenly at the ends of such intervals); second, to separate out background extinction from mass extinction for a major crisis in earth history; and third, to correct for clustering of extinctions when using the rarefaction method to estimate the percentage of species lost in a mass extinction. Also presented here is a method for estimating the magnitude of the Signor-Lipps effect, which is the incorrect assignment of extinctions that occurred during a crisis to an interval preceding the crisis because of the incompleteness of the fossil record. Estimates for the magnitudes of mass extinctions presented here are in most cases lower than those previously published. They indicate that only ∼81% of marine species died out in the great terminal Permian crisis, whereas levels of 90-96% have frequently been quoted in the literature. Calculations of the latter numbers were incorrectly based on combined data for the Middle and Late Permian mass extinctions. About 90 orders and more than 220 families of marine animals survived the terminal Permian crisis, and they embodied an enormous amount of morphological, physiological, and ecological diversity. Life did not nearly disappear at the end of the Permian, as has often been claimed.
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Leszek, Tomasz Ros
2004-01-01
Muchos autores demuestran sobre los ejemplos de sus pacientes que Sertralina es una medicación más eficaz y mejor tolerada en el tratamiento de la "depresión mayor" en el curso de las enfermedades de cáncer con metástasis. Presentamos el caso de una entrenadora de gimnasia. Many authors prove through the examples of their patients that Sertraline is a most efficient drug best accepted in the treatment of the "major depression" while patient has the cancer with multiple metastases. We prese...
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The Lunar Regolith as a Recorder of Cosmic History
Cooper, Bonnie; McKay, D.; Riofrio, L.
2012-01-01
The Moon can be considered a giant tape recorder containing the history of the solar system and Universe. The lunar regolith (soil) has recorded the early history of the Moon, Earth, the solar system and Universe. A major goal of future lunar exploration should be to find and play back existing fragments of that tape . By reading the lunar tape, we can uncover a record of planetary bombardment, as well as solar and stellar variability. The Moon can tell us much about our place in the Universe. The lunar regolith has likely recorded the original meteoritic bombardment of Earth and Moon, a violent cataclysm that may have peaked around 4 Gyr, and the less intense bombardment occurring since that time. This impact history is preserved on the Moon as regolith layers, ejecta layers, impact melt rocks, and ancient impact breccias. The impact history of the Earth and Moon possibly had profound effects on the origin and development of life. Decrease in meteor bombardment allowed life to develop on Earth. Life may have developed first on another body, such as Mars, then arrived via meteorite on Earth. The solar system may have experienced bursts of severe radiation from the Sun, other stars, or from unknown sources. The lunar regolith has recorded this radiation history in the form of implanted solar wind, solar flare materials and radiation damage. Lunar soil can be found sandwiched between layers of basalt or pyroclastic deposits. This filling constitutes a buried time capsule that is likely to contain well-preserved ancient regolith. Study of such samples will show us how the solar system has evolved and changed over time. The lunar tape recorder can provide detailed information on specific portions of solar and stellar variability. Data from the Moon also offers clues as to whether so-called fundamental constants have changed over time.
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Zheng, Xuejun; Zhu, Yuankun; Liu, Xun; Liu, Jing; Zhang, Yong; Chen, Jianguo
2014-02-01
Based on Timoshenko beam theory, a principle model is proposed to establish the relationship between electric charge and excitation acceleration, and in quasi-stasis we apply the direct piezoelectric effect of multilayer cantilever with coplanar electrode structure to evaluate the piezoelectric strain coefficient d15 and electromechanical coupling coefficient k15. They are measured as 678 pC/N and 0.74 for the commercial piezoelectric ceramic lead zirconate titanate (PZT-51) bulk specimen and 656 pC/N and 0.63 for the lead magnesium niobate (PMN) bulk specimen, and they are in agreement with the calibration and simulation values. The maximum of relative errors is less than 4.2%, so the proposed method is reliable and convenient.
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Earth Surface Processes, Landforms and Sediment Deposits
Bridge, John; Demicco, Robert
Earth surface processes, landforms and sediment deposits are intimately related - involving erosion of rocks, generation of sediment, and transport and deposition of sediment through various Earth surface environments. These processes, and the landforms and deposits that they generate, have a fundamental bearing on engineering, environmental and public safety issues; on recovery of economic resources; and on our understanding of Earth history. This unique textbook brings together the traditional disciplines of sedimentology and geomorphology to explain Earth surface processes, landforms and sediment deposits in a comprehensive and integrated way. It is the ideal resource for a two-semester course in sedimentology, stratigraphy, geomorphology, and Earth surface processes from the intermediate undergraduate to beginning graduate level. The book is also accompanied by a website hosting illustrations and material on field and laboratory methods for measuring, describing and analyzing Earth surface processes, landforms and sediments.
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Abdel Samad, Nour; Bou Dagher-Kharrat, Magda; Hidalgo, Oriane; El Zein, Rana; Douaihy, Bouchra; Siljak-Yakovlev, Sonja
2016-01-01
Despite being an important target of conservation concern and horticultural interest, Lebanese irises yet have a confusing taxonomic history and species' delimitation is often considered problematic, more especially among royal irises (Iris section Oncocyclus). Indeed, these irises of exceptionally large and spectacular flowers have radiated across Caucasus and eastern Mediterranean giving rise to a number of strict endemic taxa, many of them being considered under threat. Whilst efforts have mostly focused on clarifying the evolutionary relationships in the group based on morphological and molecular data, karyological and cytogenetic characters have been comparatively overlooked. In this study, we established for the first time the physical mapping of 35S rDNA loci and heterochromatin, and obtained karyo-morphological data for ten Lebanese Iris species belonging to four sections (Iris, Limniris, Oncocyclus and Scorpiris). Our results evidenced distinctive genomic profiles for each one of the sections, where Oncocyclus irises, while having the lowest chromosome numbers, exhibit both the highest number of 35S loci and CMA3+ sites. The continental radiation of royal irises has been accompanied by a relative karyological and cytogenetic stasis, even though some changes were observed regarding karyotype formula and asymmetry indexes. In addition to that, our results enabled taxonomic differentiation between I. germanica and I. mesopotamica-two taxa currently considered as synonyms-and highlighted the need for further studies on populations of I. persica and I. wallasiae in the Eastern Mediterranean Region.
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International Nuclear Information System (INIS)
Wetherill, G.W.; Drake, C.L.
1980-01-01
The earth is a dynamic body. The major surface manifestation of this dynamism has been fragmentation of the earth's outer shell and subsequent relative movement of the pieces on a large scale. Evidence for continental movement came from studies of geomagnetism. As the sea floor spreads and new crust is formed, it is magnetized with the polarity of the field at the time of its formation. The plate tectonics model explains the history, nature, and topography of the oceanic crust. When a lithospheric plate surmounted by continental crust collides with an oceanic lithosphere, it is the denser oceanic lithosphere that is subducted. Hence the ancient oceans have vanished and the knowledge of ancient earth will require deciphering the complex continental geological record. Geochemical investigation shows that the source region of continental rocks is not simply the depleted mantle that is characteristic of the source region of basalts produced at the oceanic ridges. The driving force of plate tectonics is convection within the earth, but much remains to be learned about the convection and interior of the earth. A brief discussion of planetary exploration is given
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Journal of Earth System Science | Indian Academy of Sciences
Indian Academy of Sciences (India)
Home; Journals; Journal of Earth System Science. Denizhan Vardar. Articles written in Journal of Earth System Science. Volume 127 Issue 1 February 2018 pp 13. Seismic stratigraphy and depositional history of the BüyükÇekmece Bay since Latest Pleistocene, Marmara Sea, Turkey · Denizhan Vardar Hakan Alp Bedri ...
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Comparative Earth history and Late Permian mass extinction
Knoll, A. H.; Bambach, R. K.; Canfield, D. E.; Grotzinger, J. P.
1996-01-01
The repeated association during the late Neoproterozoic Era of large carbon-isotopic excursions, continental glaciation, and stratigraphically anomalous carbonate precipitation provides a framework for interpreting the reprise of these conditions on the Late Permian Earth. A paleoceanographic model that was developed to explain these stratigraphically linked phenomena suggests that the overturn of anoxic deep oceans during the Late Permian introduced high concentrations of carbon dioxide into surficial environments. The predicted physiological and climatic consequences for marine and terrestrial organisms are in good accord with the observed timing and selectivity of Late Permian mass extinction.
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Directory of Open Access Journals (Sweden)
Kevan Edinborough
2005-11-01
Full Text Available This paper presents some results from my doctoral research into the evolution of bow-arrow technology using archaeological data from the south Scandinavian Mesolithic (Edinborough 2004. A quantitative approach is used to describe the morphological variation found in samples taken from over 3600 armatures from nine Danish and Swedish lithic assemblages. A linked series of statistical techniques determines the two most significant metric variables across the nine arrowhead assemblages in terms of the cultural transmission of arrowhead technology. The resultant scatterplot uses confidence ellipses to reveal highly distinctive patterns of morphological variation that are related to population-specific technological traditions. A population-level hypothesis of a socially constrained transmission mechanism is presented that may explain the unusually long period of technological stasis demonstrated by six of the nine arrowhead phase-assemblages.
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Mitrovica, J. X.; Davis, J. L.; Shapiro, I. I.
1993-01-01
We predict the present-day rates of change of the lengths of 19 North American baselines due to the glacial isostatic adjustment process. Contrary to previously published research, we find that the three dimensional motion of each of the sites defining a baseline, rather than only the radial motions of these sites, needs to be considered to obtain an accurate estimate of the rate of change of the baseline length. Predictions are generated using a suite of Earth models and late Pleistocene ice histories, these include specific combinations of the two which have been proposed in the literature as satisfying a variety of rebound related geophysical observations from the North American region. A number of these published models are shown to predict rates which differ significantly from the VLBI observations.
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Impact on the earth, ocean and atmosphere
International Nuclear Information System (INIS)
Ahrens, T.J.; O'Keefe, J.D.
1987-01-01
Several hundred impact craters produced historically and at times as early as 1.9 x 10/sup 9/ years ago with diameters in the range 10/sup -2/ to 10/sup 2/ km are observed on the surface of the earth. Earth-based and spacecraft observations of the surfaces of all the terrestrial planets and their satellites, as well as many of the icy satellites of the outer planets, indicated that impact cratering was a dominant process on planetary surfaces during the early history of the solar system. Moreover, the recent observation of a circumstellar disk around the nearby star, β-Pictoris, appears to be similar to the authors' own hypothesized protosolar disk. A disk of material around our sun has been hypothesized to have been the source of the solid planetesimals from which the earth and the other planets accreted by infall and capture. Thus it appears that the earth and the other terrestrial planets formed as a result of infall and impact of planetesimals. Although the present planets grew rapidly via accretion to their present size (in --10/sup 7/ years), meteorite impacts continue to occur on the earth and other planets. Until recently meteorite impact has been considered to be a process that was important on the earth and the other planets only early in the history of the solar system. This is no longer true. The Alvarez hypothesis suggests that the extinction of some 90% of all species, including 17 classes of dinosaurs, is associated with the 1 to 150 cm thick layer of noble-element rich dust which is found all over the earth exactly at the Cretaceous-Tertiary boundary. The enrichment of noble elements in this dust is in meteorite-like proportions. This dust is thought to represent the fine impact ejecta from a --10 km diameter asteroid interacting with the solid earth. The Alvarez hypothesis associates the extinction with the physics of a giant impact on the earth
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Assessing the physical nature of near-Earth asteroids through their dynamical histories
Fernández, Julio A.; Sosa, Andrea; Gallardo, Tabaré; Gutiérrez, Jorge N.
2014-08-01
We analyze a sample of 139 near-Earth asteroids (NEAs), defined as those that reach perihelion distances q4.8 au), having Tisserand parameters 2family comets (JFCs) in near-Earth orbits, i.e. with q4.8 au of cometary origin, but it could be even lower if the NEAs in unstable orbits listed before turn out to be bona fide asteroids from the main belt. This study strengthens the idea that NEAs and comets essentially are two distinct populations, and that periods of dormancy in comets must be rare. Most likely, active comets in near-Earth orbits go through a continuous erosion process in successive perihelion passages until disintegration into meteoritic dust and fragments of different sizes. In this scenario, 289P/Blanpain might be a near-devolatized fragment from a by now disintegrated parent comet.
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Passow, M. J.
2017-12-01
The dioramas at the American Museum of Natural History (AMNH) in New York City provide great examples of artwork depicting locations of interest and value for teaching the Earth Sciences. When the Museum was established in 1869, it—like most institutions of that time—merely provided a taxidermy collection in cases. But as it expanded into the dozens of Halls in its multiple public buildings, curators made a deliberate effort to display the specimens with backdrops depicting the habitats where the animals were collected. Such `curatorial giants' as Frank Chapman and Carl Ackley spearheaded pioneering efforts to present displays in the curved, framed settings. The impact of these large- and small-scale artworks on the Public cannot be underestimated. Instead of just viewing the remains of a dead animal, visitors are transported around the world into a wide variety of ecosystems. With no more effort than walking from one display to the next, viewers "magically travel" to the multitude of environments across Planet Earth. The dioramas may take one from mountaintop vistas to the microsystem just a few centimeters above and below the forest floor. This presentation will provide selected examples of the artwork in AMNH dioramas. The AMNH website provides numerous videos and posts about its dioramas. I will also provide insights into the creation of more recent artwork using an online interview with Sean Murtha, the artist who created many of the Hall of Ocean Life dioramas. Predating modern technologies, including color photography, television, and computers, these dioramas are rightly described as powerful tools for nurturing scientific education and environmental awareness. These dioramas frequently are utilized to teach important Earth System Science concepts to school groups and other visitors, and examples of such lessons will be included.
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Ma, Guoqing; Ye, Ting; Sun, Zhongren
2018-03-12
To compare the clinical efficacy differences between warming acupuncture and conventional acupuncture for diabetic peripheral neuropathy (DPN) with syndrome of yang deficiency and cold coagulation, obstruction of collaterals and blood stasis. A total of 64 patients were randomly divided into a warming acupuncture group and a conventional acupuncture group, 32 cases in each one. Based on basic treatment of blood glucose regulation, warming acupuncture was applied at Pishu (BL 20), Shenshu (BL 23), Guanyuanshu (BL 26), Zusanli (ST 36), Chongyang (ST 42), Quchi (LI 11) and Hegu (LI 4) in the warming acupuncture group, while acupuncture was applied at the identical acupoints in the conventional acupuncture group. Both the treatments were given once a day with an interval of one day every six days; totally the treatment was given for 4 weeks. The TCM symptom score, Toronto clinical scoring system (TCSS) and nerve conduction velocity (NCV) before and after treatment were compared in the two groups. After treatment, the TCM symptom scores in the two groups were significantly reduced (both P nervus peroneus communis, as well as sensory nerve of tibial nerve and sural nerve was improved in the warming acupuncture group (all P 0.05). Warming acupuncture and conventional acupuncture could both increase TCM symptom score, improve NCV in patients of DPN with syndrome of yang deficiency and cold coagulation, obstruction of collaterals and blood stasis; warming acupuncture has advantage in symptom improvement.
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Earth's earliest biosphere: Its origin and evolution
International Nuclear Information System (INIS)
Schopf, J.W.
1983-01-01
Some of the subjects discussed are related to the early biogeologic history, the nature of the earth prior to the oldest known rock record, the early earth and the Archean rock record, the prebiotic organic syntheses and the origin of life, Precambrian organic geochemistry, the biochemical evolution of anaerobic energy conversion, the isotopic inferences of ancient biochemistries, Archean stromatolites providing evidence of the earth's earliest benthos, Archean microfossils, the geologic evolution of the Archean-Early Proterozoic earth, and the environmental evolution of the Archean-Early Proterozoic earth. Other topics examined are concerned with geochemical evidence bearing on the origin of aerobiosis, biological and biochemical effects of the development of an aerobic environment, Early Proterozoic microfossils, the evolution of earth's earliest ecosystems, and geographic and geologic data for processed rock samples. Attention is given to a processing procedure for abiotic samples and calculation of model atmospheric compositions, and procedures of organic geochemical analysis
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Lessons from Earth's Deep Time
Soreghan, G. S.
2005-01-01
Earth is a repository of data on climatic changes from its deep-time history. Article discusses the collection and study of these data to predict future climatic changes, the need to create national study centers for the purpose, and the necessary cooperation between different branches of science in climatic research.
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Inseparability of science history and discovery
Directory of Open Access Journals (Sweden)
J. M. Herndon
2010-04-01
Full Text Available Science is very much a logical progression through time. Progressing along a logical path of discovery is rather like following a path through the wilderness. Occasionally the path splits, presenting a choice; the correct logical interpretation leads to further progress, the wrong choice leads to confusion. By considering deeply the relevant science history, one might begin to recognize past faltering in the logical progression of observations and ideas and, perhaps then, to discover new, more precise understanding. The following specific examples of science faltering are described from a historical perspective: (1 Composition of the Earth's inner core; (2 Giant planet internal energy production; (3 Physical impossibility of Earth-core convection and Earth-mantle convection, and; (4 Thermonuclear ignition of stars. For each example, a revised logical progression is described, leading, respectively, to: (1 Understanding the endo-Earth's composition; (2 The concept of nuclear georeactor origin of geo- and planetary magnetic fields; (3 The invalidation and replacement of plate tectonics; and, (4 Understanding the basis for the observed distribution of luminous stars in galaxies. These revised logical progressions clearly show the inseparability of science history and discovery. A different and more fundamental approach to making scientific discoveries than the frequently discussed variants of the scientific method is this: An individual ponders and through tedious efforts arranges seemingly unrelated observations into a logical sequence in the mind so that causal relationships become evident and new understanding emerges, showing the path for new observations, for new experiments, for new theoretical considerations, and for new discoveries. Science history is rich in "seemingly unrelated observations" just waiting to be logically and causally related to reveal new discoveries.
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Relationship between Blood Stasis Syndrome Score and Cardioankle Vascular Index in Stroke Patients
Directory of Open Access Journals (Sweden)
Ki-Ho Cho
2012-01-01
Full Text Available Blood stasis syndrome (BSS in traditional Asian medicine has been considered to correlate with the extent of atherosclerosis, which can be estimated using the cardioankle vascular index (CAVI. Here, the diagnostic utility of CAVI in predicting BSS was examined. The BSS scores and CAVI were measured in 140 stroke patients and evaluated with respect to stroke risk factors. Receiver operating characteristic (ROC curve analysis was used to determine the diagnostic accuracy of CAVI for the diagnosis of BSS. The BSS scores correlated significantly with CAVI, age, and systolic blood pressure (SBP. Multiple logistic regression analysis showed that CAVI was a significant associate factor for BSS (OR 1.55, P=0.032 after adjusting for the age and SBP. The ROC curve showed that CAVI and age provided moderate diagnostic accuracy for BSS (area under the ROC curve (AUC for CAVI, 0.703, P<0.001; AUC for age, 0.692, P=0.001. The AUC of the “CAVI+Age,” which was calculated by combining CAVI with age, showed better accuracy (0.759, P<0.0001 than those of CAVI or age. The present study suggests that the CAVI combined with age can clinically serve as an objective tool to diagnose BSS in stroke patients.
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Turrin, B. D.; Turrin, M.
2012-12-01
After "What is this rock?" the most common questions that is asked of Geologists is "How old is this rock/fossil?" For geologists considering ages back to millions of years is routine. Sorting and cataloguing events into temporal sequences is a natural tendency for all humans. In fact, it is an everyday activity for humans, i.e., keeping track of birthdays, anniversaries, appointments, meetings, AGU abstract deadlines etc… However, the time frames that are most familiar to the non scientist (seconds, minutes, hours, days, years) generally extend to only a few decades or at most centuries. Yet the vast length of time covered by Earth's history, 4.56 billion years, greatly exceeds these timeframes and thus is commonly referred to as "Deep Time". This is a challenging concept for most students to comprehend as it involves temporal and abstract thinking, yet it is key to their successful understanding of numerous geologic principles. We have developed an outdoor learning activity for general Introductory Earth Science courses that incorporates several scientific and geologic concepts such as: linear distance or stratigraphic thickness representing time, learning about major events in Earth's history and locating them in a scaled temporal framework, field mapping, abstract thinking, scaling and dimensional analysis, and the principles of radio isotopic dating. The only supplies needed are readily available in local hardware stores i.e. a 300 ft. surveyor's tape marked in feet, and tenths and hundredths of a foot, and the student's own introductory geology textbook. The exercise employs a variety of pedagogical learning modalities, including traditional lecture-based, the use of Art/Drawing, use of Visualization, Collaborative learning, and Kinesthetic and Experiential learning. Initially the students are exposed to the concept of "Deep Time" in a short conventional introductory lecture; this is followed by a 'field day'. Prior to the field exercise, students work with
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Nimbus-7 Earth radiation budget calibration history. Part 2: The Earth flux channels
Kyle, H. Lee; Hucek, Douglas Richard R.; Ardanuy, Philip E.; Hickey, John R.; Maschhoff, Robert H.; Penn, Lanning M.; Groveman, Brian S.; Vallette, Brenda J.
1994-01-01
Nine years (November 1978 to October 1987) of Nimbus-7 Earth radiation budget (ERB) products have shown that the global annual mean emitted longwave, absorbed shortwave, and net radiation were constant to within about + 0.5 W/sq m. Further, most of the small annual variations in the emitted longwave have been shown to be real. To obtain this measurement accuracy, the wide-field-of-view (WFOV) Earth-viewing channels 12 (0.2 to over 50 micrometers), 13 (0.2 to 3.8 micrometers), and 14 (0.7 to 2.8 micrometers) have been characterized in their satellite environment to account for signal variations not considered in the prelaunch calibration equations. Calibration adjustments have been derived for (1) extraterrestrial radiation incident on the detectors, (2) long-term degradation of the sensors, and (3) thermal perturbations within the ERB instrument. The first item is important in all the channels; the second, mainly in channels 13 and 14, and the third, only in channels 13 and 14. The Sun is used as a stable calibration source to monitor the long-term degradation of the various channels. Channel 12, which is reasonably stable to both thermal perturbations and sensor degradation, is used as a reference and calibration transfer agent for the drifting sensitivities of the filtered channels 13 and 14. Redundant calibration procedures were utilized. Laboratory studies complemented analyses of the satellite data. Two nearly independent models were derived to account for the thermal perturbations in channels 13 and 14. The global annual mean terrestrial shortwave and longwave signals proved stable enough to act as secondary calibration sources. Instantaneous measurements may still, at times, be in error by as much as a few Wm(exp -2), but the long-term averages are stable to within a fraction of a Wm(exp -2).
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Pulling, Azalie Cecile
The purpose of this study was to use deep time, that is geologic time as a mechanism to explore middle school students' understanding of the natural history of the earth and the evolution of life on earth. Geologic time is a logical precursor to middle school students' understanding of biological evolution. This exploratory, mixed model study used qualitative and quantitative methods in each stage of the research to explore sixth grade students, understanding of geologic time, their worldviews (e.g., conceptual ecology), and conceptual change. The study included fifty-nine students in the large group study and four case studies. The primary data collection instrument was the Geologic Timeline Survey. Additional data collection instruments and methods (e.g., concept evaluation statement, journal entries, word associations, interviews, and formal tests) were used to triangulate the study findings. These data were used to create narrative modal profiles of the categories of student thinking that emerged from the large group analysis: Middle School (MS) Scientists (correct science), MS Protoscientists (approaching correct science), MS Prescientists (dinosaur understanding), and MS Pseudoscientists (fundamental religious understanding). Case studies were used to provide a thick description of each category. This study discovered a pattern of student thinking about geologic time that moved along a knowledge continuum from pseudoscience (fundamental creationist understanding) to prescience (everyday-science understanding) to science (correct or approaching correct science). The researcher described the deep-seated misconceptions produced by the prescience thinking level, e.g., dinosaur misconceptions, and cautioned the science education community about using dinosaurs as a glamour-science topic. The most limiting conceptual frameworks found in this study were prescience (a dinosaur focus) and pseudoscience (a fundamental religious focus). An understanding of geologic time
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Life, hierarchy, and the thermodynamic machinery of planet Earth.
Kleidon, Axel
2010-12-01
Throughout Earth's history, life has increased greatly in abundance, complexity, and diversity. At the same time, it has substantially altered the Earth's environment, evolving some of its variables to states further and further away from thermodynamic equilibrium. For instance, concentrations in atmospheric oxygen have increased throughout Earth's history, resulting in an increased chemical disequilibrium in the atmosphere as well as an increased redox gradient between the atmosphere and the Earth's reducing crust. These trends seem to contradict the second law of thermodynamics, which states for isolated systems that gradients and free energy are dissipated over time, resulting in a state of thermodynamic equilibrium. This seeming contradiction is resolved by considering planet Earth as a coupled, hierarchical and evolving non-equilibrium thermodynamic system that has been substantially altered by the input of free energy generated by photosynthetic life. Here, I present this hierarchical thermodynamic theory of the Earth system. I first present simple considerations to show that thermodynamic variables are driven away from a state of thermodynamic equilibrium by the transfer of power from some other process and that the resulting state of disequilibrium reflects the past net work done on the variable. This is applied to the processes of planet Earth to characterize the generation and transfer of free energy and its dissipation, from radiative gradients to temperature and chemical potential gradients that result in chemical, kinetic, and potential free energy and associated dynamics of the climate system and geochemical cycles. The maximization of power transfer among the processes within this hierarchy yields thermodynamic efficiencies much lower than the Carnot efficiency of equilibrium thermodynamics and is closely related to the proposed principle of Maximum Entropy Production (MEP). The role of life is then discussed as a photochemical process that generates
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Cratering record in the inner solar system: Implications for earth
International Nuclear Information System (INIS)
Barlow, N.G.
1988-01-01
Internal and external processes have reworked the Earth's surface throughout its history. In particular, the effect of meteorite impacts on the early history of the earth is lost due to fluvial, aeolian, volcanic and plate tectonic action. The cratering record on other inner solar system bodies often provides the only clue to the relative cratering rates and intensities that the earth has experienced throughout its history. Of the five major bodies within the inner solar system, Mercury, Mars, and the Moon retain scars of an early episode of high impact rates. The heavily cratered regions on Mercury, Mars, and the Moon show crater size-frequency distribution curves similar in shape and crater density, whereas the lightly cratered plains on the Moon and Mars show distribution curves which, although similar to each other, are statistically different in shape and density from the more heavily cratered units. The similarities among crater size-frequency distribution curves for the Moon, Mercury, and Mars suggest that the entire inner solar system was subjected to the two populations of impacting objects but Earth and Venus have lost their record of heavy bombardment impactors. Thus, based on the cratering record on the Moon, Mercury, and Mars, it can be inferred that the Earth experienced a period of high crater rates and basin formation prior to about 3.8 BY ago. Recent studies have linked mass extinctions to large terrestrial impacts, so life forms were unable to establish themselves until impact rates decreased substantially and terrestrial conditions became more benign. The possible periodicity of mass extinctions has led to the theory of fluctuating impact rates due to comet showers in the post heavy bombardment period. The active erosional environment on the Earth complicates attempts to verify these showers by erasing geological evidence of older impact craters
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Xiong, Xing-Jiang; Wang, Zhong; Wang, Jie
2015-01-01
Coronary heart disease (CHD) is one of the leading causes of death worldwide. Moreover, angina pectoris is one of the most important types of CHD. Therefore, prevention and effective treatment of angina pectoris is of utmost importance in both China and western countries. However, undesirable effects of antianginal therapy do influence treatment adherence to a certain extent. Therefore, it's not surprising that, complementary and alternative medicine (CAM), including Chinese medicine (CM), are widely welcomed among patients with CHD, hoping that it might complement western medicine. In our previous studies, blood stasis syndrome (BSS) (Xueyu Zheng) was the main syndrome (Zheng-hou) of angina pectoris. Currently, China Food and Drug Administration authoritatively recommended more than 200 Chinese patent medicines (CPMs) as complementary or adjunctive therapies for symptom management and enhancing quality of life along with mainstream care on angina pectoris management in mainland China. This paper reviewed 4 kinds of most frequently-used CPMs by promoting blood circulation and removing blood stasis in the treatment of angina pectoris. It aims to evaluate the current evidence of CPMs in combination therapy for angina pectoris. This review indicated that CPMs as adjunctive treatment to routine antianginal therapy play an active role in reducing the incidence of primary endpoint events, decreasing anginal attack rate, and improving electrocardiogram. Additionally, CPMs have been proven relatively safe. Further rigorously designed clinical trials should be conducted to confirm the results.
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Vita-Finzi, Claudio
2012-05-13
During the last half century, advances in geomorphology-abetted by conceptual and technical developments in geophysics, geochemistry, remote sensing, geodesy, computing and ecology-have enhanced the potential value of fluvial history for reconstructing erosional and depositional sequences on the Earth and on Mars and for evaluating climatic and tectonic changes, the impact of fluvial processes on human settlement and health, and the problems faced in managing unstable fluvial systems. This journal is © 2012 The Royal Society
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The proto-Earth geo-reactor: Reassessing the hypotheses
Directory of Open Access Journals (Sweden)
Claude Degueldre
2016-09-01
The present paper focuses on the geo-reactor hypothetical conditions including history, spatial extension and regimes. The discussion based on recent calculations involves investigations on the limits in term of fissile inventory, size and power, based on coupling of geochemical reactions and stratification through the gravitational field considering behavior through the inner mantle, the boundary with the core and the core. The reconstruction allows to formulating that from the history point of view it would have been possible that the geo-reactor reached criticality in a proto-Earth period as a reactor triggered by 235-uranium and that thorium may have worked as an absorber if the actinide concentration was locally large enough. Without actinide separation the initiation of the criticality is unlikely. However did the segregation of actinides occur in any Earth layer?
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The role of impacts in the history of the early earth
French, Bevan M.
1991-01-01
The significant conclusions of a conference called 'Meteorite Impact and the Early Earth' are reported including data which support the notion that extraterrestrial impacts greatly influenced the development of the earth. The cratering of other planetary surfaces is discussed, and the energy added by meteorite impacts is characterized. The primary effects of large impacts are set forth in terms of atmospheric, oceanic, and biological considerations which suggest that the ramifications would have been significant. Contentious issues include the variation of impact rate with time in the early universe, the interpretation of the record of intense bombardment in the lunar highlands, and the effects related to alternative scenarios. Directions of future study are mentioned including the identification of terrestrial impact structures, conducting searches in the Archean, and assessing ancient impact rates.
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A new model of the Earth system nitrogen cycle: how plates and life affect the atmosphere
Johnson, B. W.; Goldblatt, C.
2017-12-01
Nitrogen is the main component of Earth's atmosphere. It plays a key role in the evolution of the biosphere and surface of Earth [1]. There are contrasting views, however, on how N has evolved on the surface of the Earth over time. Some modeling efforts [e.g., 2] indicate a steady-state level of N in the atmosphere over geologic time, while geochemical [e.g., 3], other proxies [e.g., 4], and more recent models [5] indicate the mass of N in the atmosphere can change dramatically over Earth history. This conundrum, and potential solutions to it, present distinct interpretations of the history of Earth, and teleconnections between the surface and interior of the planet have applications to other terrestrial bodies as well. To help investigate this conundrum, we have constructed an Earth-system N cycle box model. To our knowledge, this is the most capable model for addressing evolution of the N reservoirs of Earth through time. The model combines biologic and geologic processes, driven by a mantle cooling history, to more fully describe the N cycle through geologic history. In addition to a full biologic N cycle (fixing, nitrification, denitrification), we also dynamically solve for PO4 through time and we have a prescribed O2 history. Results indicate that the atmosphere of Earth could have experienced major changes in mass over geologic time. Importantly, the amount of N in the atmosphere today appears to be directly related to the total N budget of the silicate Earth. For example, high initial atmospheric mass, suggested as a solution to the Faint Young Sun Paradox [1], is drawn down over time. This supports work that indicates the mantle has significantly more N than the atmosphere does today [6]. Contrastingly, model runs with low total N result in a crash in atmospheric mass. In nearly all model runs the bulk silicate Earth contains the majority of the planet's N. [1] Goldblatt et al. (2009) Nat. Geosci., 2, 891-896. [2] Berner, R. (2006) Geology., 34, 413
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International Nuclear Information System (INIS)
Plant, J.A.; Saunders, A.D.
1996-01-01
Uranium, thorium and potassium are the main elements contributing to natural terrestrial radioactivity. The isotopes 238 U, 235 U, 232 Th and 40 K decay with half-lives so long that significant amounts remain in the earth, providing a continuing source of heat. The slow decay of these isotopes also provides the basis for radiometric age dating and isotopic modelling of the evolution of the earth and its crust. There is a complex interplay between their heat production and the processes involved in crust formation. Phenomena such as volcanism, earthquakes, and large-scale hydrothermal activity associated with ore deposition reflect the dissipation of heat energy from the earth, much of which is derived from natural radioactivity. The higher levels of radioactive elements during the early history of the earth resulted in higher heat flow. All three of the radioactive elements are strongly partitioned into the continental crust, but within the crust their distribution is determined by their different chemical properties. The behaviour of U, which has two commonly occurring oxidation states, is more complex than that of Th and K. Uranium deposits are diverse, and are mostly associated with granites, acid volcanics, or detrital sedimentary rocks. The most important U deposits economically are unconformity-type ores of Proterozoic age, in which U is enriched by up to 5 x 10 6 with respect to bulk earth values. In some cases natural radioactivity can be of environmental concern. The most significant risk is posed by accumulations of radon, the gaseous daughter product of U. (author)
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Proterozoic Milankovitch cycles and the history of the solar system.
Meyers, Stephen R; Malinverno, Alberto
2018-06-19
The geologic record of Milankovitch climate cycles provides a rich conceptual and temporal framework for evaluating Earth system evolution, bestowing a sharp lens through which to view our planet's history. However, the utility of these cycles for constraining the early Earth system is hindered by seemingly insurmountable uncertainties in our knowledge of solar system behavior (including Earth-Moon history), and poor temporal control for validation of cycle periods (e.g., from radioisotopic dates). Here we address these problems using a Bayesian inversion approach to quantitatively link astronomical theory with geologic observation, allowing a reconstruction of Proterozoic astronomical cycles, fundamental frequencies of the solar system, the precession constant, and the underlying geologic timescale, directly from stratigraphic data. Application of the approach to 1.4-billion-year-old rhythmites indicates a precession constant of 85.79 ± 2.72 arcsec/year (2σ), an Earth-Moon distance of 340,900 ± 2,600 km (2σ), and length of day of 18.68 ± 0.25 hours (2σ), with dominant climatic precession cycles of ∼14 ky and eccentricity cycles of ∼131 ky. The results confirm reduced tidal dissipation in the Proterozoic. A complementary analysis of Eocene rhythmites (∼55 Ma) illustrates how the approach offers a means to map out ancient solar system behavior and Earth-Moon history using the geologic archive. The method also provides robust quantitative uncertainties on the eccentricity and climatic precession periods, and derived astronomical timescales. As a consequence, the temporal resolution of ancient Earth system processes is enhanced, and our knowledge of early solar system dynamics is greatly improved.
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Neutron Measurements for Radiation Protection in Low Earth Orbit - History and Future
Golightly, M. J.; Se,pmes. E/
2003-01-01
The neutron environment inside spacecraft has been of interest from a scientific and radiation protection perspective since early in the history of manned spaceflight. With 1:.1e exception of a few missions which carried plutonium-fueled radioisotope thermoelectric generators, all of the neutrons inside the spacecraft are secondary radiations resulting from interactions of high-energy charged particles with nuclei in the Earth's atmosphere, spacecraft structural materials, and the astronaut's own bodies. Although of great interest, definitive measurements of the spacecraft neutron field have been difficult due to the wide particle energy range and the limited available volume and power for traditional techniques involving Bonner spheres. A multitude of measurements, however, have been made of the neutron environment inside spacecraft. The majority of measurements were made using passive techniques including metal activation fo ils, fission foils, nuclear photoemulsions, plastic track detectors, and thermoluminescent detectors. Active measurements have utilized proton recoil spectrometers (stilbene), Bonner Spheres eRe proportional counter based), and LiI(Eu)phoswich scintillation detectors. For the International Space Station (ISS), only the plastic track! thermoluminescent detectors are used with any regularity. A monitoring program utilizing a set of active Bonner spheres was carried out in the ISS Lab module from March - December 200l. These measurements provide a very limited look at the crew neutron exposure, both in time coverage and neutron energy coverage. A review of the currently published data from past flights will be made and compared with the more recent results from the ISS. Future measurement efforts using currently available techniques and those in development will be also discussed.
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Ecological and evolutionary consequences of benthic community stasis in the very deep sea (>1500 m)
Buzas, Martin A.; Hayek, Lee-Ann C.; Culver, Stephen J.; Hayward, Bruce W.; Osterman, Lisa E.
2014-01-01
An enigma of deep-sea biodiversity research is that the abyss with its low productivity and densities appears to have a biodiversity similar to that of shallower depths. This conceptualization of similarity is based mainly on per-sample estimates (point diversity, within-habitat, or α-diversity). Here, we use a measure of between-sample within-community diversity (β1H) to examine benthic foraminiferal diversity between 333 stations within 49 communties from New Zealand, the South Atlantic, the Gulf of Mexico, the Norwegian Sea, and the Arctic. The communities are grouped into two depth categories: 200–1500 m and >1500 m. β1H diversity exhibits no evidence of regional differences. Instead, higher values at shallower depths are observed worldwide. At depths of >1500 m the average β1H is zero, indicating stasis or no biodiversity gradient. The difference in β1H-diversity explains why, despite species richness often being greater per sample at deeper depths, the total number of species is greater at shallower depths. The greater number of communities and higher rate of evolution resulting in shorter species durations at shallower depths is also consistent with higher β1H values.
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Wang, Min; Fu, Jinfeng; Lv, Mengying; Tian, Yuan; Xu, Fengguo; Song, Rui; Zhang, Zunjian
2014-09-01
As a specific item mentioned in traditional Chinese medicine theory, processing can fulfill different requirements of therapies. Crude and wine-processed rhubarbs are used as drastic and mild laxatives, respectively. In this study, a practical method based on ultra-fast liquid chromatography coupled with diode-array detection and ion trap time-of-flight mass spectrometry was developed to screen and analyze multiple absorbed bioactive components and metabolites in the serum of both normal and acute blood stasis rats after oral administration of crude or wine-processed rhubarbs. A total of 16 compounds, mainly including phase II metabolites, were tentatively identified. Possible explanations for the processing-induced changes in pharmacological effects of traditional Chinese medicines were first explored at serum pharmacochemistry level. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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History Made for Tomorrow: Hakka Tulou
Directory of Open Access Journals (Sweden)
Richard M. Yelland
2013-11-01
Full Text Available The documentary film, History Made for Tomorrow: Hakka Tulou was an October 2010 release by History Channel International. This film is an in-depth study on the green building techniques and sustainable lifestyle of the Hakka people of Southern China with a focus on the ancient Tulou rammed earth structures. The television program follows West Virginia University research professor, Ruifeng Liang, as he initiates scientific studies to back claims that the rammed earth Tulou structures are “the greenest buildings in the world”, and Canadian architect, Jorg Ostrowski, of Autonomous Sustainable Housing Inc., who has been researching the ecological footprint of Hakka communities since August 2007, to promote them as “eco-villages” of best practices for planet Earth’s sustainability. The author is credited as Director, Writer, and Producer of this film. This paper is based on the script of the production.
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Human impact on the planet: an earth system science perspective and ethical considerations
Williams, Richard S.
2002-01-01
The modern Earth Narrative, the scientific story of the 4.5 billion-year natural and human history of the Earth, has emerged from the solid foundation of two factual concepts: Deep (or Geologic) Time and Biological Evolution. spread acceptance of the Earth Narrative is critically important as we begin the third millennium, because it provides a clear understanding of the growing impact of human population growth and associated activities on the Earth System, especially the negative impact on Earth?s biosphere. It is important for humans to realize that we are but one of 4,500 species of mammals that exist on Earth and that we are but one species in the estimated 30 to 100 million species that form the complex biosphere. We also need to recognize that all species exist within the physical limits imposed by the geosphere. We are totally dependent on the biosphere for food, oxygen, and other necessities of life. mans are one of the latest results of biological evolution operating over a long period of Geologic Time. We find ourselves on Earth, after 4.5 billion years of Earth history by chance, not by design. Humans have become so successful at modifying their environment that many of the natural limitations on the expansion of populations of our fellow animals have been overcome by technological and cultural innovations. According to Peter Raven, ?Humans, at a current population of 6 billion [expected to nearly double by 2050], are consuming or wasting about 50 percent of the total net biological productivity on land and 50 percent of the available supply of freshwater. The overwhelming and expanding human presence leaves less and less room in the environment for other biota.? st century will be a pivotal time in the fate of Earth?s biosphere. Whereas human modification of the geosphere will slowly recover over time, human changes to the biosphere are a far more consequential matter? extinction of a species is forever! Will humans effectively use our new knowledge of
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Bringing Earth Magnetism Research into the High School Physics Classroom
Smirnov, A. V.; Bluth, G.; Engel, E.; Kurpier, K.; Foucher, M. S.; Anderson, K. L.
2015-12-01
We present our work in progress from an NSF CAREER project that aims to integrate paleomagnetic research and secondary school physics education. The research project is aimed at quantifying the strength and geometry of the Precambrian geomagnetic field. Investigation of the geomagnetic field behavior is crucial for understanding the mechanisms of field generation, and the development of the Earth's atmosphere and biosphere, and can serve as a focus for connecting high-level Earth science research with a standard physics curriculum. High school science teachers have participated in each summer field and research component of the project, gaining field and laboratory research experience, sets of rock and mineral samples, and classroom-tested laboratory magnetism activities for secondary school physics and earth science courses. We report on three field seasons of teacher field experiences and two years of classroom testing of paleomagnetic research materials merged into physics instruction on magnetism. Students were surveyed before and after dedicated instruction for both perceptions and attitude towards earth science in general, then more specifically on earth history and earth magnetism. Students were also surveyed before and after instruction on major earth system and magnetic concepts and processes, particularly as they relate to paleomagnetic research. Most students surveyed had a strongly positive viewpoint towards the study of Earth history and the importance of studying Earth Sciences in general, but were significantly less drawn towards more specific topics such as mineralogy and magnetism. Students demonstrated understanding of Earth model and the basics of magnetism, as well as the general timing of life, atmospheric development, and magnetic field development. However, detailed knowledge such as the magnetic dynamo, how the magnetic field has changed over time, and connections between earth magnetism and the development of an atmosphere remained largely
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Raising awareness for research on earth walls, and earth scientific aspects
van den Ancker, Hanneke; Jungerius, Pieter Dirk; Baas, Henk; Groenewoudt, Bert; Peen, Charlotte
2013-04-01
A conference to raise awareness In the Netherlands, little research on earth walls has been done. To improve attention for earth walls, a number of organisations, including Geoheritage NL, organized a conference at the RCE, the Cultural Heritage Agency of the Netherlands. The conference* presented a state-of-the-art of research done. The book with the presentations, and extra case studies added, was published in December 2012. The book concludes with a research action list, including earth science research, and can be downloaded freely from the internet. It has English summaries. The earth science aspects Historical earth walls do not only add cultural value to a landscape, but also geodiversity value. Apart from geomorphological aspects, the walls contain information about past land- and climate conditions: - They cover up a former topography, a past landscape. A relevant source of scientific information where lands are levelled, as is the case in many parts of The Netherlands; - The soil formation under the earth wall is a reference soil. The soil formation in the top of the wall gives insight in the rate of soil formation in relationship with the age and parent material of the wall; - The soil profiles of different age have ecological significance. Older walls with a more pronounced soil formation often hold forest flora that has disappeared from the surrounding environment, such as historical bush or tree species, autogenetic DNA material or a specific soil fauna; - The materials in the earth walls tell about the process of wall-building. Paleosols and sedimentary structures in the earth walls, in the gullies and colluvial fans along the walls contain information about past land management and climate. - The eroded appearance of the earth walls is part of their history, and contain information about past management and land conditions, has ecological relevance, for example for insects, and is often visually more interesting. Insight in the rates of erosion are
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Isotopes as clues to the origin and earliest differentiation history of the Earth.
Jacobsen, Stein B; Ranen, Michael C; Petaev, Michael I; Remo, John L; O'Connell, Richard J; Sasselov, Dimitar D
2008-11-28
Measurable variations in (182)W/(183)W, (142)Nd/(144)Nd, (129)Xe/(130)Xe and (136)XePu/(130)Xe in the Earth and meteorites provide a record of accretion and formation of the core, early crust and atmosphere. These variations are due to the decay of the now extinct nuclides (182)Hf, (146)Sm, (129)I and (244)Pu. The (l82)Hf-(182)W system is the best accretion and core-formation chronometer, which yields a mean time of Earth's formation of 10Myr, and a total time scale of 30Myr. New laser shock data at conditions comparable with those in the Earth's deep mantle subsequent to the giant Moon-forming impact suggest that metal-silicate equilibration was rapid enough for the Hf-W chronometer to reliably record this time scale. The coupled (146)Sm-(147)Sm chronometer is the best system for determining the initial silicate differentiation (magma ocean crystallization and proto-crust formation), which took place at ca 4.47Ga or perhaps even earlier. The presence of a large (129)Xe excess in the deep Earth is consistent with a very early atmosphere formation (as early as 30Myr); however, the interpretation is complicated by the fact that most of the atmospheric Xe may be from a volatile-rich late veneer.
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The Earth as a Distant Planet A Rosetta Stone for the Search of Earth-Like Worlds
Vázquez, M; Montañés Rodríguez, P
2010-01-01
Is the Earth, in some way, special? Or is our planet but one of the millions of other inhabited planets within our galaxy? This is an exciting time to be asking this old question, because for the first time in history, the answer is within reach. In The Earth as a Distant Planet, the authors set themselves as external observers of our Solar System from an astronomical distance. From that perspective, the authors describe how the Earth, the third planet in distance to the central star, can be catalogued as having its own unique features and as capable of sustaining life. The knowledge gained from this original perspective is then applied to the ongoing search for planets outside the solar system, or exoplanets. Since the discovery in 1992 of the first exoplanet, the number of known planets has increased exponentially. Ambitious space missions are already being designed for the characterization of their atmospheres and to explore the possibility that they host life. The exploration of Earth and the rest of the ...
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Walker, R. J.; Puchtel, I. S.; Brandon, A. D.; Horan, M. F.; James, O. B.
2007-01-01
The highly siderophile elements (HSE) include Re, Os, Ir, Ru, Pt and Pd. These elements are initially nearly-quantitatively stripped from planetary silicate mantles during core segregation. They then may be re-enriched in mantles via continued accretion sans continued core segregation. This suite of elements and its included long-lived radiogenic isotopes systems (Re-187 (right arrow) Os-187; Pt-190 (right arrow) Os-186) can potentially be used to fingerprint the characteristics of late accreted materials. The fingerprints may ultimately be useful to constrain the prior nebular history of the dominant late accreted materials, and to compare the proportion and genesis of late accretionary materials added to the inner planets. The past ten years have seen considerable accumulation of isotopic and compositional data for HSE present in the Earth's mantle, lunar mantle and impact melt breccias, and Martian meteorites. Here we review some of these data and consider the broader implications of the compiled data.
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Annual review of earth and planetary sciences. Volume 16
International Nuclear Information System (INIS)
Wetherill, G.W.; Albee, A.L.; Stehli, F.G.
1988-01-01
Various papers on earth and planetary science topics are presented. The subjects addressed include: role and status of earth science field work; phase relations of prealuminous granitic rocks and their petrogenetic implications; chondritic meteorites and the solar nebula; volcanic winters; mass wasting on continental margins; earthquake ground motions; ore deposits as guides to geologic history of the earth; geology of high-level nuclear waste disposal; and tectonic evolution of the Caribbean. Also discussed are: the earth's rotation; the geophysics of a restless caldera (Long Valley, California); observations of cometary nuclei; geology of Venus; seismic stratigraphy; in situ-produced cosmogenic isotopes in terrestrial rocks; time variations of the earth's magnetic field; deep slabs, geochemical heterogeneity, and the large-scale structure of mantle convection; early proterozoic assembly and growth of Laurentia; concepts and methods of high-resolution event stratigraphy
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NASA's Earth Science Data Systems: A "Bit of History" and Observations
Ramapriyan, H. K.
2008-01-01
NASA has significantly improved its Earth Science Data Systems over the last two decades. Open data policy and inexpensive (or free) availability of data has promoted data usage by broad research and applications communities. Flexibility, accommodation of diversity, evolvability, responsiveness to community feedback are key to success.
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Digest of NASA earth observation sensors
Drummond, R. R.
1972-01-01
A digest of technical characteristics of remote sensors and supporting technological experiments uniquely developed under NASA Applications Programs for Earth Observation Flight Missions is presented. Included are camera systems, sounders, interferometers, communications and experiments. In the text, these are grouped by types, such as television and photographic cameras, lasers and radars, radiometers, spectrometers, technology experiments, and transponder technology experiments. Coverage of the brief history of development extends from the first successful earth observation sensor aboard Explorer 7 in October, 1959, through the latest funded and flight-approved sensors under development as of October 1, 1972. A standard resume format is employed to normalize and mechanize the information presented.
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International Earth Science Constellation (ESC) Introduction
Guit, William J.; Machado, Michael J.
2016-01-01
This is the Welcome and Introduction presentation for the International Earth Science Constellation (ESC) Mission Operations Working Group (MOWG) meeting held in Albuquerque NM from September 27-29. It contains an org chart, charter, history, significant topics to be discussed, AquaAura 2017 inclination adjust maneuver calendar, a-train long range plans, upcoming events, and action items.
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Atmospheric pollution: history, science and regulation
Energy Technology Data Exchange (ETDEWEB)
Jacobson, M.Z. [Stanford University, Stanford, CA (USA). Dept. of Civil and Environmental Engineering
2002-07-01
The book provides an introduction to the history and science of major air pollution issues. It begins with an introduction to the history of discovery of chemicals in the atmosphere, and moves on to a discussion of the evolution of the earth's atmosphere. It then discusses five major atmospheric pollution topics: urban outdoor air pollution, indoor air pollution, acid deposition, stratospheric ozone depletion, and global climate change. The book contains numerous student examples and problems and over 200 color illustrations and photographs.
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International Nuclear Information System (INIS)
Lasa, J.
1991-01-01
The paper contain the actual results of investigations of the influence of the human activity on the Earth's ozone layer. History of the ozone measurements and of the changes in its concentrations within the last few years are given. The influence of the trace gases on both local and global ozone concentrations are discussed. The probable changes of the ozone concentrations are presented on the basis of the modelling investigations. The effect of a decrease in global ozone concentration on human health and on biosphere are also presented. (author). 33 refs, 36 figs, 5 tabs
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Alonso Guervós, Marta
2006-01-01
Los carcinomas epidermoides de cabeza y cuello (CECC) ocupan el octavo lugar entre las neoplasias del sexo masculino, presentando el Principado de Asturias una de las tasas de incidencia más altas de España. Aunque se han realizado importantes avances en su diagnóstico y tratamiento, la supervivencia se ha modificado poco en los últimos años debido a que se diagnostican en estadios avanzados. El desarrollo de metástasis en los ganglios linfáticos cervicales es el factor que más influye en la ...
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The evolution of the Earth-Moon system
International Nuclear Information System (INIS)
Finch, D.G.
1982-01-01
The tidally-induced couple acting on the Moon, due to friction between the oceans and their beds, is calculated as a function of the Earth-Moon separation. The function is found to be proportional to 1 +d/R 3 , and not the previously used 1/R 6 . By use of this new function it is found that the present rate of lunar recession gives an acceptable history for the system if it is assumed the Moon was initially in a close geo-stationary orbit 4 billion years ago, when perturbed by the condensation of the Earth's core. (Auth.)
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Wang, Yuanqing; Yan, Jianye; Li, Shunxiang; Wang, Wei; Cai, Xiong; Huang, Dan; Gong, Limin; Li, Xin
2016-01-01
Angelica sinensis and Aurantii fructu used in a pair, named Danggui-Zhiqiao herb-pair (DZHP), which was rich in essential oil and has been adopted to promote blood circulation, dispel blood stasis, and relieve pain in traditional Chinese medicine (TCM). To analyze the composition and pharmacological effects of essential oil from DZHP. The composition of the essential oil from DZHP was analyzed by gas chromatography/mass spectrometry (GC/MS). Its analgesic activity was evaluated by acetic acid-induced writhing test and hot plate test. The hemorheology test was carried out to evaluate the effect on hemorheology in rats with blood stasis syndrome. Twenty-eight components were identified and the main components were α -pinene (3.07%), β -pinene (2.0%), β -myrcene (3.71%), D-limonene (49.28%), γ -terpinen (9.53%), α -terpinolene (1.80%), α -terpineol (2.02%), β -bisabolene (1.13%), butylidenephthalide (1.43%), and Z-ligustilide (16.08%). The pharmacology test showed that the essential oil significantly inhibited the number of writhes induced by acetic acid with inhibition rate of 44.64% and significantly increased hot-plate latency compared with control group from 30 to 90 min after oral administration of drugs in mice. It could significantly decrease plasma viscosity, whole blood relative index at high and low shear rate, whole blood reduced viscosity at high and low shear rate, and erythrocyte rigidity index in hemorheology test. The composition of the essential oil of DZHP was determined successfully and it had analgesic and promoting blood circulation activities. Angelica sinensis and Aurantii fructu used in a pair, named Danggui-Zhiqiao herb-pair (DZHP), which was rich in Essential oil and has been adopted to promote blood circulation, dispel blood stasis and relieve pain in traditional Chinese medicine (TCM).Twenty-eight components were identified and the main components were α -pinene (3.07%), β -pinene (2.0%), β -myrcene (3.71%), D-limonene (49.28%),
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The twin sister planets Venus and Earth why are they so different?
Malcuit, Robert J
2014-01-01
This book explains how it came to be that Venus and Earth, while very similar in chemical composition, zonation, size and heliocentric distance from the Sun, are very different in surface environmental conditions. It is argued here that these differences can be accounted for by planetoid capture processes and the subsequent evolution of the planet-satellite system. Venus captured a one-half moon-mass planetoid early in its history in the retrograde direction and underwent its "fatal attraction scenario" with its satellite (Adonis). Earth, on the other hand, captured a moon-mass planetoid (Luna) early in its history in prograde orbit and underwent a benign estrangement scenario with its captured satellite.
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History Matching: Towards Geologically Reasonable Models
DEFF Research Database (Denmark)
Melnikova, Yulia; Cordua, Knud Skou; Mosegaard, Klaus
This work focuses on the development of a new method for history matching problem that through a deterministic search finds a geologically feasible solution. Complex geology is taken into account evaluating multiple point statistics from earth model prototypes - training images. Further a function...... that measures similarity between statistics of a training image and statistics of any smooth model is introduced and its analytical gradient is computed. This allows us to apply any gradientbased method to history matching problem and guide a solution until it satisfies both production data and complexity...
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Xe isotopic constraints on cycling of deep Earth volatiles
Parai, R.; Mukhopadhyay, S.
2017-12-01
The modern deep Earth volatile budget reflects primordial volatiles delivered during accretion, radiogenic ingrowth of volatile species (e.g., 40Ar produced by 40K decay), outgassing in association with mantle processing, and regassing via subduction. The noble gases are unique volatile tracers in that they are chemically inert, but are thought to be trapped within hydrous alteration phases in downwelling lithologies. Noble gases thus provide a tracer of volatile transport between the deep Earth and surface reservoirs. Constraints on the fluxes of noble gases between deep Earth and surface reservoirs over time can accordingly be used to provide insight into temperature conditions at subduction zones, limits on volatile cycling, and the evolving distribution of major volatile species in terrestrial reservoirs over time. Xe isotope systematics in mantle-derived rocks show that 80-90% of the mantle Xe budget is derived from recycling of atmospheric Xe, indicating that atmospheric Xe is retained in subducting slabs beyond depths of magma generation in subduction zones over Earth history. We present an integrated model of Xe cycling between the mantle and atmosphere in association with mantle processing over Earth history. We test a wide variety of outgassing and regassing rates and take the evolution of the atmospheric Xe isotopic composition [e.g., 1] into account. Models in which the deep Earth transitions from a net outgassing to net regassing regime best satisfy Xe isotopic constraints from mantle-derived rocks [2-6]. [1] Avice et al., 2017; Nature Communications, 8; [2] Mukhopadhyay, 2012, Nature 486, 101-104; [3] Parai et al., 2012, EPSL 359-360, 227-239; [4] Parai and Mukhopadhay, 2015, G-cubed 16, 719-735; [5] Peto et al., 2013, EPSL 369-370, 13-23; [6] Tucker et al., 2012, EPSL 355-356, 244-254.
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Lu, Yan; Li, Tao
2014-03-01
To explore the effect of Chinese drugs for activating blood circulation and removing blood stasis (CDABCRBS) on carotid atherosclerotic plaque and long-term ischemic cerebrovascular events. By using open and control method, effect of 4 groups of platelet antagonists, platelet antagonists + CDABCRBS, platelet antagonists +atorvastatin, platelet antagonists +atorvastatin +CDABCRBS on carotid atherosclerotic plaque and long-term ischemic cerebrovascular events of 90 cerebral infarction patients were analyzed. Through survival analysis, there was no statistical difference in the effect of the 4 interventions on the variation of carotid stenosis rates or ischemic cerebrovascular events (P > 0.05). The occurrence of ischemic cerebrovascular events could be postponed by about 4 months in those treated with platelet antagonists + CDABCRBS and platelet antagonists + atorvastatin +CDABCRBS. By multivariate Logistic analysis, age, hypertension, and clopidogrel were associated with stenosis of extracranial carotid arteries (P cerebrovascular accidents (P cerebrovascular events. CDABCRBS could effectively prolong the occurrence time of ischemic cerebrovascular events.
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Reducing greenhouses and the temperature history of earth and Mars
Sagan, C.
1977-01-01
It has been suggested that NH3 and other reducing gases were present in the earth's primitive atmosphere, enhancing the global greenhouse effect; data obtained through isotopic archeothermometry support this hypothesis. Computations have been applied to the evolution of surface temperatures on Mars, considering various bolometric albedos and compositions. The results are of interest in the study of Martian sinuous channels which may have been created by aqueous fluvial errosion, and imply that clement conditions may have previously occurred on Mars, and may occur in the future.
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Earth-approaching asteroids: Populations, origin, and compositional types
Shoemaker, E. M.; Helin, E. F.
1978-01-01
Origin, physical properties, and discovery history of smaller asteroids are reviewed. They appear to link the main belt objects, namely the comets and meteorites. Physical observations suggest that a wide variety of compositional types are represented among the near-earth asteroids; the apparent rarity of carbonaceous objects is stated.
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Global Change and the Earth System
Pollack, Henry N.
2004-08-01
The Earth system in recent years has come to mean the complex interactions of the atmosphere, biosphere, lithosphere and hydrosphere, through an intricate network of feedback loops. This system has operated over geologic time, driven principally by processes with long time scales. Over the lifetime of the solar system, the Sun has slowly become more radiant, and the geography of continents and oceans basins has evolved via plate tectonics. This geography has placed a first-order constraint on the circulation of ocean waters, and thus has strongly influenced regional and global climate. At shorter time scales, the Earth system has been influenced by Milankovitch orbital factors and occasional exogenous events such as bolide impacts. Under these influences the system chugged along for eons, until some few hundred thousand years ago, when one remarkable species evolved: Homo sapiens. As individuals, humans are of course insignificant in shaping the Earth system, but collectively the six billion human occupants of the planet now rival ``natural'' processes in modifying the Earth system. This profound human influence underlies the dubbing of the present epoch of geologic history as the ``Anthropocene.''
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Studies in the history of astronomy. Number 19, 1987
Gurshtein, A. A.
Papers are presented on such topics as the history of the exploration of Venus, the history of the discovery of the relic radiation, Copernicus' star catalog, Euler's contribution to potential theory in connection with the theory of the earth's figure, the role of astrology in ancient culture, and the history of the study of astronomical refraction. Attention is also given to astronomy in Kazakhstan during the Second World War, the contribution of Arago to the development of astrophysics instrumentation, and the work on astronomy written by Kirik of Novgorod in the year 1136.
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Drastic Environmental Change on Mars: Applying the Lessons Learned on Earth
Fairen, A.; Schulze-Makuch, D.; Irwin, L. N.
2014-12-01
Rapid and drastic environmental change has occurred frequently on Earth, posing a critical challenge to life. However, directional selection has overcome those challenges and driven life on our planet to ever increasing diversity and complexity. Based on our knowledge of the natural history of Earth, the effect of drastic environmental changes on a planet's biosphere can be attributed to three main factors: (1) the nature and time scale of change, (2) the composition of the biosphere prior to change, and (3) the nature of the environment following the change. Mars has undergone even larger environmental changes than Earth, from habitable conditions under which the origin of life (or transfer of life from Earth) seem plausible, to a dry and cold planet punctuated by wetter conditions. Given its planetary history, life on Mars could have retreated to a psychrophilic lifestyle in the deep subsurface or to environmental near-surface niches, such as hydrothermal regions and caves. Further, strong directional selection could have pushed putative martian life to evolve alternating cycles between active and dormant forms, as well as the innovation of new traits adapted to challenging near-surface conditions (e.g., use of H2O2 or perchlorates as antifreeze compounds).
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Earth Sciences Division annual report 1990
Energy Technology Data Exchange (ETDEWEB)
NONE
1991-06-01
This Annual Report presents summaries of selected representative research activities grouped according to the principal disciplines of the Earth Sciences Division: Reservoir Engineering and Hydrogeology, Geology and Geochemistry, and Geophysics and Geomechanics. Much of the Division`s research deals with the physical and chemical properties and processes in the earth`s crust, from the partially saturated, low-temperature near-surface environment to the high-temperature environments characteristic of regions where magmatic-hydrothermal processes are active. Strengths in laboratory and field instrumentation, numerical modeling, and in situ measurement allow study of the transport of mass and heat through geologic media -- studies that now include the appropriate chemical reactions and the hydraulic-mechanical complexities of fractured rock systems. Of particular note are three major Division efforts addressing problems in the discovery and recovery of petroleum, the application of isotope geochemistry to the study of geodynamic processes and earth history, and the development of borehole methods for high-resolution imaging of the subsurface using seismic and electromagnetic waves. In 1989 a major DOE-wide effort was launched in the areas of Environmental Restoration and Waste Management. Many of the methods previously developed for and applied to deeper regions of the earth will in the coming years be turned toward process definition and characterization of the very shallow subsurface, where man-induced contaminants now intrude and where remedial action is required.
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ADVANCING TORPOR INDUCING TRANSFER HABITATS FOR HUMAN STASIS TO MARS
National Aeronautics and Space Administration — SpaceWorks proposes the development of an advanced habitat system for transporting crews between the Earth and Mars. This new and innovative habitat design is...
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Chen, Zhao; Cao, Yanfeng; He, Shuaibing; Qiao, Yanjiang
2018-01-01
Action (" gongxiao " in Chinese) of traditional Chinese medicine (TCM) is the high recapitulation for therapeutic and health-preserving effects under the guidance of TCM theory. TCM-defined herbal properties (" yaoxing " in Chinese) had been used in this research. TCM herbal property (TCM-HP) is the high generalization and summary for actions, both of which come from long-term effective clinical practice in two thousands of years in China. However, the specific relationship between TCM-HP and action of TCM is complex and unclear from a scientific perspective. The research about this is conducive to expound the connotation of TCM-HP theory and is of important significance for the development of the TCM-HP theory. One hundred and thirty-three herbs including 88 heat-clearing herbs (HCHs) and 45 blood-activating stasis-resolving herbs (BAHRHs) were collected from reputable TCM literatures, and their corresponding TCM-HPs/actions information were collected from Chinese pharmacopoeia (2015 edition). The Kennard-Stone (K-S) algorithm was used to split 133 herbs into 100 calibration samples and 33 validation samples. Then, machine learning methods including supported vector machine (SVM), k-nearest neighbor (kNN) and deep learning methods including deep belief network (DBN), convolutional neutral network (CNN) were adopted to develop action classification models based on TCM-HP theory, respectively. In order to ensure robustness, these four classification methods were evaluated by using the method of tenfold cross validation and 20 external validation samples for prediction. As results, 72.7-100% of 33 validation samples including 17 HCHs and 16 BASRHs were correctly predicted by these four types of methods. Both of the DBN and CNN methods gave out the best results and their sensitivity, specificity, precision, accuracy were all 100.00%. Especially, the predicted results of external validation set showed that the performance of deep learning methods (DBN, CNN) were better
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False Negatives for Remote Life Detection on Ocean-Bearing Planets: Lessons from the Early Earth.
Reinhard, Christopher T; Olson, Stephanie L; Schwieterman, Edward W; Lyons, Timothy W
2017-04-01
Ocean-atmosphere chemistry on Earth has undergone dramatic evolutionary changes throughout its long history, with potentially significant ramifications for the emergence and long-term stability of atmospheric biosignatures. Though a great deal of work has centered on refining our understanding of false positives for remote life detection, much less attention has been paid to the possibility of false negatives, that is, cryptic biospheres that are widespread and active on a planet's surface but are ultimately undetectable or difficult to detect in the composition of a planet's atmosphere. Here, we summarize recent developments from geochemical proxy records and Earth system models that provide insight into the long-term evolution of the most readily detectable potential biosignature gases on Earth-oxygen (O 2 ), ozone (O 3 ), and methane (CH 4 ). We suggest that the canonical O 2 -CH 4 disequilibrium biosignature would perhaps have been challenging to detect remotely during Earth's ∼4.5-billion-year history and that in general atmospheric O 2 /O 3 levels have been a poor proxy for the presence of Earth's biosphere for all but the last ∼500 million years. We further suggest that detecting atmospheric CH 4 would have been problematic for most of the last ∼2.5 billion years of Earth's history. More broadly, we stress that internal oceanic recycling of biosignature gases will often render surface biospheres on ocean-bearing silicate worlds cryptic, with the implication that the planets most conducive to the development and maintenance of a pervasive biosphere will often be challenging to characterize via conventional atmospheric biosignatures. Key Words: Biosignatures-Oxygen-Methane-Ozone-Exoplanets-Planetary habitability. Astrobiology 17, 287-297.
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Huang, Xiaochen; Su, Shulan; Duan, Jin-Ao; Sha, Xiuxiu; Zhu, Kavin Yue; Guo, Jianming; Yu, Li; Liu, Pei; Shang, Erxin; Qian, Dawei
2016-06-20
Traditional Chinese medicine (TCM) is used under the guidance of the theory of traditional Chinese medical sciences in clinical application. The Chinese herbal formula, Shaofu Zhuyu decoction (SFZYD), is considered as an effective prescription for treating Cold - Stagnation and Blood - Stasis (CSBS) primary dysmenorrhea. The previous studies showed the SFZYD exhibited significant anti-inflammation and analgesic effect. In this present study the metabolomics of CSBS primary dysmenorrhea diseased rats and the cytokine transcription in PHA stimulated-PBMC were investigated to explore the effects and mechanisms. Explore a valuable insight into the effects and mechanisms of SFZYD on Cold - Stagnation and Blood - Stasis primary dysmenorrhea rats. We established CSBS primary dysmenorrhea diseased rats according the clinical symptoms. A targeted tandem mass spectrometry (MS/MS)-based metabolomic platform was used to evaluate the metabolic profiling changes and the intervention effects by SFZYD. The PBMC cell was adopted to explore the mechanisms by analyzing the signaling pathway evaluated by expression of inflammatory cytokines, c-jun and c-fos and corresponding phosphorylation levels. Estradiol, oxytocin, progesterone, endothelin, β-endorphin and PGF2α were restored back to the normal level after the treatment of SFZYD. Total twenty-five metabolites (10 in plasma and 15 in urine), up-regulated or down-regulated, were identified. These identified biomarkers underpinning the metabolic pathway including pentose and glucuronate interconversions, steroid hormone biosynthesis, and glycerophospholipid metabolism are disturbed in model rats. Among these metabolites, twenty one potential biomarkers were regulated after SFZYD treated. The compound of paeoniflorin, a major bioactive compound in SFZYD, was proved to regulate the MAPK signaling pathway by inhibiting the expression of IL-1β, IL-2, IL-10, IL-12, TNFα, INFγ, c-jun and c-fos in PHA stimulated-PBMC. These findings
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O'Malley-James, Jack T; Greaves, Jane S; Raven, John A; Cockell, Charles S
2015-05-01
Earth will become uninhabitable within 2-3 Gyr as a result of the increasing luminosity of the Sun changing the boundaries of the habitable zone (HZ). Predictions about the future of habitable conditions on Earth include declining species diversity and habitat extent, ocean loss, and changes to geochemical cycles. Testing these predictions is difficult, but the discovery of a planet that is an analogue to future Earth could provide the means to test them. This planet would need to have an Earth-like biosphere history and to be approaching the inner edge of the HZ at present. Here, we assess the possibility of finding such a planet and discuss the benefits of analyzing older Earths. Finding an old-Earth analogue in nearby star systems would be ideal, because this would allow for atmospheric characterization. Hence, as an illustrative example, G stars within 10 pc of the Sun are assessed as potential old-Earth-analog hosts. Six of these represent good potential hosts. For each system, a hypothetical Earth analogue is placed at locations within the continuously habitable zone (CHZ) that would allow enough time for Earth-like biosphere development. Surface temperature evolution over the host star's main sequence lifetime (assessed by using a simple climate model) is used to determine whether the planet would be in the right stage of its late-habitable lifetime to exhibit detectable biosignatures. The best candidate, in terms of the chances of planet formation in the CHZ and of biosignature detection, is 61 Virginis. However, planet formation studies suggest that only a small fraction (0.36%) of G stars in the solar neighborhood could host an old-Earth analogue. If the development of Earth-like biospheres is rare, requiring a sequence of low-probability events to occur, biosphere evolution models suggest they are rarer still, with only thousands being present in the Galaxy as a whole.
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North pole, South pole the quest to understand Earth's magnetism
Turner, Gillian
2010-01-01
Going all the way back to the Roman legend of a shepherd whose iron-studded boots stuck to the rocks, this book charts the history of the earth's magnetism, which intrigued and stumped scientists and ordinary people for centuries. Absorbing and accessible, it is a lively study of what exactly magnetic force is, what causes it, and what its place has been throughout scientific history, offering detailed insights into the inner workings of the planet and its magnetic shield.
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Lunar paleotides and the origin of the earth-moon system
International Nuclear Information System (INIS)
Anderson, A.J.
1978-01-01
A new method for determining the early history of the Earth-Moon system is described. Called the study of lunar paleotides, it describes a method for explaining features of the remnant lunar gravity field, and the generation of the lunar mascons. A method for the determination of Earth-Moon distances compared with the radiometric ages of the maria is developed. It is shown that the Moon underwent strong anomalous gravitational tidal forces, for a duration t 6 yr, prior to the formation of the mascon surfaces. As these tidal forces had not been present at the time of the formation of the Moon, this shows that the Moon could not have been formed in orbit about the Earth. (Auth.)
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Origin and earliest state of the earth's hydrosphere
International Nuclear Information System (INIS)
Cogley, J.G.; Henderson-Sellers, A.
1984-01-01
The origin and earliest history of the earth's hydrosphere, the inventory of excess volatiles defined by Rubey in 1951, can be constrained within wide but useful limits by a consideration of empirical and theoretical evidence from astrophysics and geology. Models for the evolution of the solar system from the protoplanetary nebula and for the growth of the earth to its present dimensions suggest quite strongly that the hydrosphere came into being during accretion. Its format, with H 2 O mostly in the oceans, CO 2 mostly in sediments, and a residual atmosphere dominated by N 2 , CO 2 , and H 2 O was established at a very early data and has persisted without large, destabilizing climatic excursions until the present day. Alternative accounts of early history, in which the earth either loses a massive primordial atmosphere or acquires its secondary atmosphere by gradual degassing, seem improbable on the basis of a series of circumstantial but cumulatively persuasive arguments. The difficulty of dissipating a massive atmosphere of solar composition in reasonable times, the likelihood that accretion was a highly energetic process and that it triggered early segregation of the core, and the tendency of the planet to accumulate volatiles preferentially in the later stages of accretion are examples of arguments favoring an early origin for the hydrosphere. Several geological isotope systems which can be sampled today require early separation of the atmosphere and probably the hydrosphere ass a whole; these systems recorrd radiogenic enrichment patterns in the noble gases and stable isotope fractionations which suggest an early origin of the biosphere. Certain geological indicators of atmsopheric composition. and the broadly equable character of the rock record, are also consistent with a hydrosphere established in the earliest stages of history and having an initial neutral or weakly reduced composition
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Near Earth Objects - a threat and an opportunity
Tate, Jonathan R.
2003-05-01
In the past decade the hazard posed to the Earth by Near Earth Objects (NEOs) has generated considerable scientific and public interest. A number of major films, television programmes and media reports have brought the issue to public attention. From an educational perspective an investigation into NEOs and the effects of impacts on the Earth forms a topical and dynamic basis for study in a huge range of subjects, not just scientific. There are clear routes to chemistry, physics, mathematics and biology, but history, psychology, geography, palaeontology and geology are just a selection of other subjects involved. A number of projects have been established, mainly in the USA, to determine the extent of the hazard, and to develop ways of countering it, but the present situation is far from satisfactory. Current detection and follow-up programmes are underfunded and lack international coordination.
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Perigee: Zero, a Unified Theory of Cultural Heritage and Geological History
Davias, M. E.
2006-05-01
Perigee: Zero proposes a unified theory to solve enigmas haunting our cultural heritage and the Earth's geological history. We maintain the theory is simple and provable. We document the terraforming of the Earth by the cratering and accretive action of impacting comets and resulting ejecta, during events occurring at regular intervals over the past 15,000 years. Visual evidence of geomorphed landscape is presented using the perspective of high-resolution satellite imaging and DEM data. Correlation of these images with physical and historic evidence has proven supportive. Sections of the lithosphere have been lofted thousands of kilometers. Excised trenches have filled with water, or left as barren desert. Blankets of ejecta have overlain the continents and their inhabitants. The atmosphere was disrupted by the influx of dust and energy. Composed of hydrated silica, the comets have added a significant percentage of the water and unusually pure silicate (as sand and clay) now present on earth. Human history is immersed in these events. Oral and written works comprising much of the world's cultural heritage provide us with accounts of catastrophic damage visited upon Earth and its inhabitants. Those accounts describe mountains being moved, large expanses of the earth being swept clean - or replaced with open ocean, civilizations buried, years of darkness, the world flooded. Our forefathers invoked deities from the heavens, or perhaps giant kangaroos. We invoke impactors from the Taurid Complex, a simple and natural process, as most of its progenitor's mass may be missing. The damage to the earth is interpreted as the result of hundreds of grazing and nearly tangential impacts, suggesting decaying orbits of earth-captured cosmic bodies as a plausible solution. The events are seen occurring when the low point of the orbit -the perigee- reaches the earth's surface; in effect Perigee: Zero.
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Harfoot, Michael B. J.; Beerling, David J.; Lomax, Barry H.; Pyle, John A.
2007-04-01
We use the Cambridge two-dimensional (2-D) chemistry-radiation transport model to investigate the implications for column O3 and near-surface ultraviolet radiation (UV), of variations in atmospheric O2 content over the Phanerozoic (last 540 Myr). Model results confirm some earlier 1-D model investigations showing that global annual mean O3 column increases monotonically with atmospheric O2. Sensitivity studies indicate that changes in temperature and N2O exert a minor influence on O3 relative to O2. We reconstructed Earth's O3 history by interpolating the modeled relationship between O3 and O2 onto two Phanerozoic O2 histories. Our results indicate that the largest variation in Phanerozoic column O3 occurred between 400 and 200 Myr ago, corresponding to a rise in atmospheric O2 to ˜1.5 times the present atmospheric level (PAL) and subsequent fall to ˜0.5 PAL. The O3 response to this O2 decline shows latitudinal differences, thinning most at high latitudes (30-40 Dobson units (1 DU = 0.001 atm cm) at 66°N) and least at low latitudes (5-10 DU at 9°N) where a "self-healing" effect is evident. This O3 depletion coincides with significant increases in the near-surface biologically active UV radiation at high latitudes, +28% as weighted by the Thimijan spectral weighting function. O3 and UV changes were exacerbated when we incorporated a direct feedback of the terrestrial biosphere on atmospheric chemistry, through enhanced N2O production as the climate switched from an icehouse to a greenhouse mode. On the basis of a summary of field and laboratory experimental evidence, we suggest that these UV radiation increases may have exerted subtle rather than catastrophic effects on ecosystem processes.
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Mineral remains of early life on Earth? On Mars?
Iberall, Robbins E.; Iberall, A.S.
1991-01-01
The oldest sedimentary rocks on Earth, the 3.8-Ga Isua Iron-Formation in southwestern Greenland, are metamorphosed past the point where organic-walled fossils would remain. Acid residues and thin sections of these rocks reveal ferric microstructures that have filamentous, hollow rod, and spherical shapes not characteristic of crystalline minerals. Instead, they resemble ferric-coated remains of bacteria. Because there are no earlier sedimentary rocks to study on Earth, it may be necessary to expand the search elsewhere in the solar system for clues to any biotic precursors or other types of early life. A study of morphologies of iron oxide minerals collected in the southern highlands during a Mars sample return mission may therefore help to fill in important gaps in the history of Earth's earliest biosphere. -from Authors
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Harper, Charles L., Jr.; Jacobsen, Stein B.
1992-01-01
The very early history of the Earth has been one of the great enduring puzzles in the history of geology. We report evidence which clearly can be described as a vestige of a beginning, because the evidence that we report cannot be interpreted in any other way except as a geochemical signal of processes active in the very early history of the Earth. The evidence itself is a very small anomaly in the abundance of SM-146. The primary aims of this study were to: (1) verify the existence of the 'lost continents' of the Hadean era; and (2) determine their mean age.
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The Cambridge Illustrated History of Astronomy
Hoskin, Michael
Expertly written and lavishly illustrated, The Cambridge Illustrated History of Astronomy offers a unique account of astronomical theory and practice from antiquity to the present day. How did Moslems of the Middle Ages use astronomy to calculate the direction of Mecca from far-flung corners of the Islamic world? Who was the only ancient Greek to suspect that the earth might revolve around the sun? How did Christopher Columbus abuse his knowledge of a lunar eclipse predicted by an astronomical almanac? Packed with anecdotes and intriguing detail, this book describes how we observed the sky and interpreted what we saw at different periods of history; how this influenced our beliefs and mythology; and how great astronomers contributed to what we now know. The result is a lively and highly visual history of astronomy - a compelling read for specialists and non-specialists alike.
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Modes of Contintental Sediment Storage and the History of Atmospheric Oxygen
Husson, J. M.; Peters, S. E.
2015-12-01
Documenting the history of atmospheric oxygen levels, and the processes that have governed that history, are among the most fundamental of problems in Earth science. Diverse observations from sedimentary petrography, isotope geochemistry, stratigraphy and trace element geochemistry have led to a model wherein concentrations of oxygen experienced two significant rises: the first 'Great Oxidation Event' near the Archean-Proterozoic boundary, and a second near the Proterozoic-Phanerozoic boundary. Despite ongoing debates over important details in the history of atmospheric O2, there is widespread agreement that the burial and long-term storage of sedimentary organic matter derived from photosynthesis, which represents net O2 production over consumption by respiration, is the primary driver of oxygenation of the atmosphere. In this regard, sedimentation on the continents is vitally important; today, >90% of buried organic matter occurs in sediments deposited on continental crust. Here we use 23,813 rock units, distributed among 949 geographic regions in North America, from the Macrostrat database to constrain patterns of sedimentation through Earth history. Sedimentary packages are low in number in the Archean, increase to a higher steady state value across the transition to the Proterozoic, and rise again across the Proterozoic-Phanerozoic boundary during the final stage in the formation of the Great Unconformity. Map-based data from polar Eurasia and Australia show qualitatively similar macrostratigraphic patterns of sediment abundance. The temporal similarities between continental sedimentation and the putative history of pO2 are sensible in the context of organic carbon burial. A simple model of burial and weathering on North America predicts two significant rises in pO2. These results suggest that the changing ability of the continents to serve as long-term organic carbon storage reservoirs, presumably due to geodynamic processes, has exerted a first-order control
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Spectra of Earth-like Planets through Geological Evolution around FGKM Stars
Rugheimer, S.; Kaltenegger, L.
2018-02-01
Future observations of terrestrial exoplanet atmospheres will occur for planets at different stages of geological evolution. We expect to observe a wide variety of atmospheres and planets with alternative evolutionary paths, with some planets resembling Earth at different epochs. For an Earth-like atmospheric time trajectory, we simulate planets from the prebiotic to the current atmosphere based on geological data. We use a stellar grid F0V to M8V ({T}{eff}=7000–2400 K) to model four geological epochs of Earth's history corresponding to a prebiotic world (3.9 Ga), the rise of oxygen at 2.0 Ga and at 0.8 Ga, and the modern Earth. We show the VIS–IR spectral features, with a focus on biosignatures through geological time for this grid of Sun-like host stars and the effect of clouds on their spectra. We find that the observability of biosignature gases reduces with increasing cloud cover and increases with planetary age. The observability of the visible O2 feature for lower concentrations will partly depend on clouds, which, while slightly reducing the feature, increase the overall reflectivity, and thus the detectable flux of a planet. The depth of the IR ozone feature contributes substantially to the opacity at lower oxygen concentrations, especially for the high near-UV stellar environments around F stars. Our results are a grid of model spectra for atmospheres representative of Earth's geological history to inform future observations and instrument design and are available online at http://carlsaganinstitute.org/data/.
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Eiró Díaz, Noemí
2016-01-01
Existe la hipótesis de que la inflamación participa en la promoción de las condiciones que conducen al cáncer. Las interacciones entre las células inflamatorias y las células tumorales afectan directamente a la progresión tumoral. De hecho, las células inflamatorias y los factores inmunomoduladores presentes en el microambiente tumoral influyen en la progresión tumoral y el desarrollo de metástasis. Se ha considerado que el infiltrado leucocitario era un mecanismo de defensa intrínseca contra...
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Archean Isotope Anomalies as a Window into the Differentiation History of the Earth
Wainwright, A. N.; Debaille, V.; Zincone, S. A.
2018-05-01
No resolvable µ142Nd anomaly was detected in Paleo- Mesoarchean rocks of São Francisco and West African cratons. The lack of µ142Nd anomalies outside of North America and Greenland implies the Earth differentiated into at least two distinct domains.
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Directory of Open Access Journals (Sweden)
Grant M. Young
2013-05-01
evolution not take off after the Great Oxidation Event of the Paleoproterozoic? The answer may lie in the huge scar left by the ∼2023 Ma Vredefort impact in South Africa, and in the worldwide organic carbon-rich deposits of the Shunga Event, attesting to the near-extirpation of life and possible radical alteration of the course of Earth history.
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Sulfur in Earth's Mantle and Its Behavior During Core Formation
Chabot, Nancy L.; Righter,Kevin
2006-01-01
The density of Earth's outer core requires that about 5-10% of the outer core be composed of elements lighter than Fe-Ni; proposed choices for the "light element" component of Earth's core include H, C, O, Si, S, and combinations of these elements [e.g. 1]. Though samples of Earth's core are not available, mantle samples contain elemental signatures left behind from the formation of Earth's core. The abundances of siderophile (metal-loving) elements in Earth's mantle have been used to gain insight into the early accretion and differentiation history of Earth, the process by which the core and mantle formed, and the composition of the core [e.g. 2-4]. Similarly, the abundance of potential light elements in Earth's mantle could also provide constraints on Earth's evolution and core composition. The S abundance in Earth's mantle is 250 ( 50) ppm [5]. It has been suggested that 250 ppm S is too high to be due to equilibrium core formation in a high pressure, high temperature magma ocean on early Earth and that the addition of S to the mantle from the subsequent accretion of a late veneer is consequently required [6]. However, this earlier work of Li and Agee [6] did not parameterize the metalsilicate partitioning behavior of S as a function of thermodynamic variables, limiting the different pressure and temperature conditions during core formation that could be explored. Here, the question of explaining the mantle abundance of S is revisited, through parameterizing existing metal-silicate partitioning data for S and applying the parameterization to core formation in Earth.
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Earth Sciences Division annual report 1990
International Nuclear Information System (INIS)
1991-06-01
This Annual Report presents summaries of selected representative research activities grouped according to the principal disciplines of the Earth Sciences Division: Reservoir Engineering and Hydrogeology, Geology and Geochemistry, and Geophysics and Geomechanics. Much of the Division's research deals with the physical and chemical properties and processes in the earth's crust, from the partially saturated, low-temperature near-surface environment to the high-temperature environments characteristic of regions where magmatic-hydrothermal processes are active. Strengths in laboratory and field instrumentation, numerical modeling, and in situ measurement allow study of the transport of mass and heat through geologic media -- studies that now include the appropriate chemical reactions and the hydraulic-mechanical complexities of fractured rock systems. Of particular note are three major Division efforts addressing problems in the discovery and recovery of petroleum, the application of isotope geochemistry to the study of geodynamic processes and earth history, and the development of borehole methods for high-resolution imaging of the subsurface using seismic and electromagnetic waves. In 1989 a major DOE-wide effort was launched in the areas of Environmental Restoration and Waste Management. Many of the methods previously developed for and applied to deeper regions of the earth will in the coming years be turned toward process definition and characterization of the very shallow subsurface, where man-induced contaminants now intrude and where remedial action is required
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Oxygen free period in the history of Earth and life in it
Directory of Open Access Journals (Sweden)
Георгій Ілліч Рудько
2016-06-01
Full Text Available The development of Earth in the context of its formation as also emergence of the original atmosphere and hydrosphere are presented in the article. Main stages of the atmosphere evolution have occurred in the Archaean. The mechanisms of life origin, their impact on environmental development and changes are described as well. A brief description of the most ancient sediments composed by the archaebacteria and cyanobacteria is considered.
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Toth, L. T.; van Woesik, R.; Murdoch, T. J. T.; Smith, S. R.; Ogden, J. C.; Precht, W. F.; Aronson, R. B.
2014-09-01
With coral populations in decline globally, it is critical that we tease apart the relative impacts of ecological and physical perturbations on reef ecosystems to determine the most appropriate management actions. This study compared the trajectories of benthic assemblages from 1998 to 2011 in three no-take reserves and three sites open to fishing, at 7-9 and 15-18 m depth in the Florida Keys. We evaluated temporal changes in the benthic assemblage to infer whether fisheries bans in no-take reserves could have cascading effects on the benthos in this region. Coral cover declined significantly over time at our sites and that trend was driven almost exclusively by decline of the Orbicella (formerly Montastraea) annularis species complex. Other coral taxa showed remarkable stasis and resistance to a variety of environmental perturbations. Protection status did not influence coral or macroalgal cover. The dynamics of corals and macroalgae in the 15 years since the reserves were established in 1997 suggest that although the reserves protected fish, they were of no perceptible benefit to Florida's corals.
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Liu, Xiao-Qi; Peng, Dan-Hong; Wang, Yan-Ping; Xie, Rong; Chen, Xin-Lin; Yu, Chun-Quan; Li, Xian-Tao
2018-05-03
Phlegm and blood stasis syndrome (PBSS) is one of the main syndromes in coronary heart disease (CHD). Syndromes of Chinese medicine (CM) are lack of quantitative and easyimplementation diagnosis standards. To quantify and standardize the diagnosis of PBSS, scales are usually applied. To evaluate the diagnostic accuracy of CM diagnosis scale of PBSS in CHD. Six hundred patients with stable angina pectoris of CHD, 300 in case group and 300 in control group, will be recruited from 5 hospitals across China. Diagnosis from 2 experts will be considered as the "gold standard". The study design consists of 2 phases: pilot test is used to evaluate the reliability and validity, and diagnostic test is used to assess the diagnostic accuracy of the scale, including sensitivity, specififi city, likelihood ratio and area under the receiver operator characteristic (ROC) curve. This study will evaluate the diagnostic accuracy of CM diagnosis scale of PBSS in CHD. The consensus of 2 experts may not be ideal as a "gold standard", and itself still requires further study. (No. ChiCTR-OOC-15006599).
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Lanzerotti, Louis J.
2010-03-01
Earth's space environment often offers surprises upon the introduction of new technologies. The history of some space weather impacts on communications demonstrates this vividly. Such history was on my mind during a recent trip to Newfoundland, Canada. Nestled in an eastern inlet, the small fishing village of Heart's Content marks the landing site of the first transatlantic telegraph cable, in 1866, laid by the famous ship Great Eastern with the financial backing of Cyrus Field. The building and laying of this cable is an engineering saga in its own right; subsequent Europe-to-North America telegraph cables in the nineteenth and twentieth centuries also had Newfoundland coastal ports as their termini. Geomagnetic storm-produced ground currents that flowed through this and other telegraph cables seriously affected transmission and reception of signals.
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Biological modulation of planetary atmospheres: The early Earth scenario
Schidlowski, M.
1985-01-01
The establishment and subsequent evolution of life on Earth had a profound impact on the chemical regime at the planet's surface and its atmosphere. A thermodynamic gradient was imposed on near-surface environments that served as the driving force for a number on important geochemical transformations. An example is the redox imbalance between the modern atmosphere and the material of the Earth's crust. Current photochemical models predict extremely low partial pressures of oxygen in the Earth's prebiological atmosphere. There is widespread consensus that any large-scale oxygenation of the primitive atmosphere was contingent on the advent of biological (autotrophic) carbon fixation. It is suggested that photoautotrophy existed both as a biochemical process and as a geochemical agent since at least 3.8 Ga ago. Combining the stoichiometry of the photosynthesis reaction with a carbon isotope mass balance and current concepts for the evolution of the stationary sedimentary mass as a funion of time, it is possible to quantify, the accumulation of oxygen and its photosynthetic oxidation equivalents through Earth history.
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Earth mortars and earth-lime renders
Directory of Open Access Journals (Sweden)
Maria Fernandes
2008-01-01
Full Text Available Earth surface coatings play a decorative architectural role, apart from their function as wall protection. In Portuguese vernacular architecture, earth mortars were usually applied on stone masonry, while earth renders and plasters were used on indoors surface coatings. Limestone exists only in certain areas of the country and consequently lime was not easily available everywhere, especially on granite and schist regions where stone masonry was a current building technique. In the central west coast of Portugal, the lime slaking procedure entailed slaking the quicklime mixed with earth (sandy soil, in a pit; the resulting mixture would then be combined in a mortar or plaster. This was also the procedure for manufactured adobes stabilized with lime. Adobe buildings with earth-lime renderings and plasters were also traditional in the same region, using lime putty and lime wash for final coat and decoration. Classic decoration on earth architecture from the 18th-19th century was in many countries a consequence of the François Cointeraux (1740-1830 manuals - Les Cahiers d'Architecture Rurale" (1793 - a French guide for earth architecture and building construction. This manual arrived to Portugal in the beginning of XIX century, but was never translated to Portuguese. References about decoration for earth houses were explained on this manual, as well as procedures about earth-lime renders and ornamentation of earth walls; in fact, these procedures are exactly the same as the ones used in adobe buildings in this Portuguese region. The specific purpose of the present paper is to show some cases of earth mortars, renders and plasters on stone buildings in Portugal and to explain the methods of producing earth-lime renders, and also to show some examples of rendering and coating with earth-lime in Portuguese adobe vernacular architecture.
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Granulomatosis de Wegener Semejando Cáncer Epidermoide de Nasofaringe y Metástasis Pulmonares.
Directory of Open Access Journals (Sweden)
Gustavo Adolfo Martín Small
2011-01-01
Full Text Available La granulomatosis de Wegener (GW es una enfermedad idiopática, con posible componente autoinmune, que aparece generalmente en la quinta década de vida, caracterizándose por lesiones granulomatosas necrotizantes y vasculitis en vías aéreas y riñón. Paciente femenino de 54 años, quien desde Noviembre del 2008, presenta rinorrea, prurito y eritema en borde nasal inferior izquierdo, recibe antibióticos sin mejoría de los síntomas. En las radiografías torácicas, se observan dos radiopacidades redondeadas, de 4 cm de diámetro, sugestivas de lesiones tumorales en ambos campos pulmonares. La biopsia reporta cáncer epidermoide de alto grado, sospechándose primario en nasofaringe. Es remitida, por deterioro de condiciones, al Servicio de Neumonología del Hospital Universitario de Caracas el 18/03/2009, presentando disnea, tos productiva, placas purpúricas dolorosas en manos y pies, hipoacusia, hiperpigmentación del paladar duro, leucoplaquias y lesiones costrosas en lengua, insuficiencia renal (creatinina en 6,11 mg/dL y trombocitopenia. En TAC de tórax, se evidencian tumores mayores de 5 cm de diámetro, algunos con bordes bien definidos y otros mal delimitados con broncograma aéreo. Diagnostico definitivo de GW por serología. La GW con su afectación sistémica puede simular otras entidades como neoplasias de cabeza y cuello con metástasis pulmonares. Cuando las manifestaciones sistémicas son floridas debe sospecharse GW como diagnóstico diferencial. Palabras claves: Wegener, Granulomatosis, Vasculitis, Cáncer epidermoide.
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Terraforming the Planets and Climate Change Mitigation on Earth
Toon, O. B.
2008-12-01
Hopefully, purposeful geo-engineering of the Earth will remain a theoretical concept. Of course, we have already inadvertently changed the Earth, and over geologic history life has left an indelible imprint on our planet. We can learn about geo-engineering schemes by reference to Earth history, for example climate changes after volcanic eruptions provide important clues to using sulfates to modify the climate. The terrestrial planets and Titan offer additional insights. For instance, Mars and Venus both have carbon dioxide dominated greenhouses. Both have more than 10 times as much carbon dioxide in their atmospheres as Earth, and both absorb less sunlight than Earth, yet one is much colder than Earth and one is much hotter. These facts provide important insights into carbon dioxide greenhouses that I will review. Mars cools dramatically following planet wide dust storms, and Titan has what is referred to as an anti- greenhouse climate driven by aerosols. These data can be used to reassure us that we can model aerosol caused changes to the climate of a planet, and also provide examples of aerosols offsetting a gas-driven greenhouse effect. People have long considered whether we might make the other planets habitable. While most of the schemes considered belong in the realm of science fiction, it is possible that some schemes might be practical. Terraforming brings to mind a number of issues that are thought provoking, but not so politically charged as geo-engineering. For example: What criteria define habitability, is it enough for people to live in isolated glass enclosures, or do we need to walk freely on the planet? Different creatures have different needs. Is a planet habitable if plants can thrive in the open, or do animals also need to be free? Are the raw materials present on any planet to make it habitable? If not, can we make the materials, or do we have to import them? Is it ethical to change a planetary climate? What if there are already primitive
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Sohl, L.
2014-04-01
The Neoproterozoic "Snowball Earth" glaciations ( 750-635 Ma) have been a special focus for outer habitable zone investigations, owing in large part to a captivating and controversial hypothesis suggesting that Earth may have only narrowly escaped a runaway icehouse state on multiple occasions (a.k.a. "the hard snowball"; Hoffman and Schrag 2001). A review of climate simulations exploring snowball inception (Godderis et al. 2011) reveals that a broad range of models (EBMs, EMICs and AGCMs) tend to yield hard snowball solutions, whereas models with greater 3-D dynamic response capabilities (AOGCMs) typically do not, unless some of their climate feedback responses (e.g., wind-driven ocean circulation, cloud forcings) are disabled (Poulsen and Jacobs 2004). This finding raises the likelihood that models incorporating dynamic climate feedbacks are essential to understanding how much flexibility there may be in the definition of a planet's habitable zone boundaries for a given point in its history. In the first of a series of new Snowball Earth simulations, we use the NASA/GISS ModelE2 Global Climate Model - a 3-D coupled atmosphere/ocean model with dynamic sea ice response - to explore the impacts of wind-driven ocean circulation, clouds and deep ocean circulation on the sea ice front when solar luminosity and atmospheric carbon dioxide are reduced to Neoproterozoic levels (solar = 94%, CO2 = 40 ppmv). The simulation includes a realistic Neoproterozoic land mass distribution, which is concentrated at mid- to tropical latitudes. After 300 years, the sea ice front is established near 30 degrees latitude, and after 600 years it remains stable. As with earlier coupled model simulations we conclude that runaway glacial states would have been difficult to achieve during the Neoproterozoic, and would be more likely to have occurred during earlier times in Earth history when solar luminosity was less. Inclusion of dynamic climate feedback capabilities in habitable zone
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Sapiens a brief history of humankind
Harari, Yuval Noah
2015-01-01
From a renowned historian comes a groundbreaking narrative of humanity’s creation and evolution—a #1 international bestseller—that explores the ways in which biology and history have defined us and enhanced our understanding of what it means to be “human.” One hundred thousand years ago, at least six different species of humans inhabited Earth. Yet today there is only one—homo sapiens. What happened to the others? And what may happen to us? Most books about the history of humanity pursue either a historical or a biological approach, but Dr. Yuval Noah Harari breaks the mold with this highly original book that begins about 70,000 years ago with the appearance of modern cognition. From examining the role evolving humans have played in the global ecosystem to charting the rise of empires, Sapiens integrates history and science to reconsider accepted narratives, connect past developments with contemporary concerns, and examine specific events within the context of larger ideas. Dr. Harari also comp...
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Lenhardt, W. C.
2015-12-01
Global Mapping Project, Web-enabled Landsat Data (WELD), International Satellite Land Surface Climatology Project (ISLSCP), hydrology, solid earth dynamics, sedimentary geology, climate modeling, integrated assessments and so on all have needs for or have worked to develop consistently integrated data layers for Earth and environmental science. This paper will present an overview of an abstract notion of data layers of this types, what we are referring to as reference data layers for Earth and environmental science, highlight some historical examples, and delve into new approaches. The concept of reference data layers in this context combines data availability, cyberinfrastructure and data science, as well as domain science drivers. We argue that current advances in cyberinfrastructure such as iPython notebooks and integrated science processing environments such as iPlant's Discovery Environment coupled with vast arrays of new data sources warrant another look at the how to create, maintain, and provide reference data layers. The goal is to provide a context for understanding science needs for reference data layers to conduct their research. In addition, to the topics described above this presentation will also outline some of the challenges to and present some ideas for new approaches to addressing these needs. Promoting the idea of reference data layers is relevant to a number of existing related activities such as EarthCube, RDA, ESIP, the nascent NSF Regional Big Data Innovation Hubs and others.
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Signals from the planets, via the Sun to the Earth
Solheim, J.-E.
2013-12-01
The best method for identification of planetary forcing of the Earth's climate is to investigate periodic variations in climate time series. Some natural frequencies in the Earth climate system seem to be synchronized to planetary cycles, and amplified to a level of detection. The response by the Earth depends on location, and in global averaged series, some planetary signals may be below detection. Comparing sea level rise with sunspot variations, we find phase variations, and even a phase reversal. A periodogram of the global temperature shows that the Earth amplifies other periods than observed in sunspots. A particular case is that the Earth amplifies the 22 yr Hale period, and not the 11 yr Schwabe period. This may be explained by alternating peak or plateau appearance of cosmic ray counts. Among longer periods, the Earth amplifies the 60 yr planetary period and keeps the phase during centennials. The recent global warming may be interpreted as a rising branch of a millennium cycle, identified in ice cores and sediments and also recorded in history. This cycle peaks in the second half of this century, and then a 500 yr cooling trend will start. An expected solar grand minimum due to a 200 yr cycle will introduce additional cooling in the first part of this century.
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Maccone, Claudio
2014-08-01
Big History is an emerging academic discipline which examines history scientifically from the Big Bang to the present. It uses a multidisciplinary approach based on combining numerous disciplines from science and the humanities, and explores human existence in the context of this bigger picture. It is taught at some universities. In a series of recent papers ([11] through [15] and [17] through [18]) and in a book [16], we developed a new mathematical model embracing Darwinian Evolution (RNA to Humans, see, in particular, [17] and Human History (Aztecs to USA, see [16]) and then we extrapolated even that into the future up to ten million years (see 18), the minimum time requested for a civilization to expand to the whole Milky Way (Fermi paradox). In this paper, we further extend that model in the past so as to let it start at the Big Bang (13.8 billion years ago) thus merging Big History, Evolution on Earth and SETI (the modern Search for ExtraTerrestrial Intelligence) into a single body of knowledge of a statistical type. Our idea is that the Geometric Brownian Motion (GBM), so far used as the key stochastic process of financial mathematics (Black-Sholes models and related 1997 Nobel Prize in Economics!) may be successfully applied to the whole of Big History. In particular, in this paper we derive the Statistical Drake Equation (namely the statistical extension of the classical Drake Equation typical of SETI) can be regarded as the “frozen in time” part of GBM. This makes SETI a subset of our Big History Theory based on GBMs: just as the GBM is the “movie” unfolding in time, so the Statistical Drake Equation is its “still picture”, static in time, and the GBM is the time-extension of the Drake Equation. Darwinian Evolution on Earth may be easily described as an increasing GBM in the number of living species on Earth over the last 3.5 billion years. The first of them was RNA 3.5 billion years ago, and now 50 million living species or more exist, each
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A history of presatellite investigations of the earth's radiation budget
Hunt, G. E.; Kandel, R.; Mecherikunnel, A. T.
1986-01-01
The history of radiation budget studies from the early twentieth century to the advent of the space age is reviewed. By the beginning of the 1960's, accurate radiative models had been developed capable of estimating the global and zonally averaged components of the radiation budget, though great uncertainty in the derived parameters existed due to inaccuracy of the data describing the physical parameters used in the model, associated with clouds, the solar radiation, and the gaseous atmospheric absorbers. Over the century, the planetary albedo estimates had reduced from 89 to 30 percent.
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Surface history of Mercury - Implications for terrestrial planets
Murray, B. C.; Strom, R. G.; Trask, N. J.; Gault, D. E.
1975-01-01
A plausible surface history of Mercury is presented which is suggested by Mariner 10 television pictures. Five periods are postulated which are delineated by successive variations in the modification of the surface by external and internal processes: accretion and differentiation, terminal heavy bombardment, formation of the Caloris basin, flooding of that basin and other areas, and light cratering accumulated on the smooth plains. Each period is described in detail; the overall history is compared with the surface histories of Venus, Mars, and the moon; and the implications of this history for earth are discussed. It is tentatively concluded that: Mercury is a differentiated planet most likely composed of a large iron core enclosed by a relatively thin silicate layer; heavy surface bombardment occurred about four billion years ago, which probably affected all the inner planets, and was followed by a period of volcanic activity; no surface modifications caused by tectonic, volcanic, or atmospheric processes took place after the volcanic period.
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Searching the Heavens and the Earth: This History of Jesuit Observatories
Udías, Agustín
2003-10-01
Jesuits established a large number of astronomical, geophysical and meteorological observatories during the 17th and 18th centuries and again during the 19th and 20th centuries throughout the world. The history of these observatories has never been published in a complete form. Many early European astronomical observatories were established in Jesuit colleges. During the 17th and 18th centuries Jesuits were the first western scientists to enter into contact with China and India. It was through them that western astronomy was first introduced in these countries. They made early astronomical observations in India and China and they directed for 150 years the Imperial Observatory of Beijing. In the 19th and 20th centuries a new set of observatories were established. Besides astronomy these now included meteorology and geophysics. Jesuits established some of the earliest observatories in Africa, South America and the Far East. Jesuit observatories constitute an often forgotten chapter of the history of these sciences. This volume is aimed at all scientists and students who do not want to forget the Jesuit contributions to science. Link: http://www.wkap.nl/prod/b/1-4020-1189-X
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Directory of Open Access Journals (Sweden)
Nadia Aguilera Calvo
2015-06-01
Full Text Available Fundamento: nimotuzumab es un novedoso anticuerpo monoclonal humanizado, con efecto antitumoral, que reconoce el receptor del factor de crecimiento epidérmico sobrexpresado en muchos tumores malignos de origen epitelial, como: esófago, pulmón, glioblastoma multiforme y próstata. Es usado en combinación con las terapias oncoespecificas, como quimioterapia o radiosensibilizador. Hasta la fecha se han tratado más de 2000 pacientes con este producto, además, es el primer anticuerpo monoclonal registrado en el país para pacientes pediátricos. Objetivo: describir los eventos adversos asociados con el nimotuzumab en pacientes con cáncer de pulmón de células no pequeñas portadores de metástasis cerebral incluidos en un ensayo clínico. Métodos: se analizaron las características de base de los pacientes, así como la frecuencia, intensidad y relación de causalidad de los eventos reportados. La población de estudio la conformaron todos los pacientes incluidos en el ensayo clínico. Resultados: la mayoría de los eventos fueron de intensidad leve a moderada y no requirieron la suspensión del tratamiento. Los eventos adversos más frecuentes fueron: astenia, anorexia, cefalea y vértigos; efectos reportados en estudios previos. Conclusiones: nimotuzumab es un fármaco seguro para el tratamiento de pacientes aquejados de cáncer de pulmón de células no pequeñas y metástasis cerebral.
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Ferruginous conditions: A dominant feature of the ocean through Earth’s history
DEFF Research Database (Denmark)
Poulton, Simon W.; Canfield, Donald Eugene
2011-01-01
, iron-rich (ferruginous) oceanic conditions often goes unrecognized, but refined techniques are currently providing evidence to suggest that ferruginous deep-ocean conditions were likely dominant throughout much of Earth's history. The prevalence of this redox state suggests that a detailed appraisal......The reconstruction of oceanic paleoredox conditions on Earth is essential for investigating links between biospheric oxygenation and major periods of biological innovation and extinction, and for unravelling feedback mechanisms associated with paleoenvironmental change. The occurrence of anoxic...
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Earth history. Low mid-Proterozoic atmospheric oxygen levels and the delayed rise of animals.
Planavsky, Noah J; Reinhard, Christopher T; Wang, Xiangli; Thomson, Danielle; McGoldrick, Peter; Rainbird, Robert H; Johnson, Thomas; Fischer, Woodward W; Lyons, Timothy W
2014-10-31
The oxygenation of Earth's surface fundamentally altered global biogeochemical cycles and ultimately paved the way for the rise of metazoans at the end of the Proterozoic. However, current estimates for atmospheric oxygen (O2) levels during the billion years leading up to this time vary widely. On the basis of chromium (Cr) isotope data from a suite of Proterozoic sediments from China, Australia, and North America, interpreted in the context of data from similar depositional environments from Phanerozoic time, we find evidence for inhibited oxidation of Cr at Earth's surface in the mid-Proterozoic (1.8 to 0.8 billion years ago). These data suggest that atmospheric O2 levels were at most 0.1% of present atmospheric levels. Direct evidence for such low O2 concentrations in the Proterozoic helps explain the late emergence and diversification of metazoans. Copyright © 2014, American Association for the Advancement of Science.
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A Tale of Two Earths: Reconciling the Lunar and Terrestrial Hadean Records
Boehnke, Patrick
2016-01-01
Studying early Earth history is complicated by the fact that the rock record doesn’t extend past 4 Ga and our only record for the Hadean (>4 Ga) comes to us from detrital zircons from the Jack Hills in Western Australia. The Hadean zircon record extends back to almost 4.4 Ga and has revealed that the early Earth may have had liquid water, a felsic crust, plate boundary interactions, and possibly a biosphere. On the other hand, analyses of lunar and meteoritic samples are used to argue for a...
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Critical Thresholds in Earth-System Dynamics
Rothman, D.
2017-12-01
The history of the Earth system is a story of change. Some changesare gradual and benign, but others, especially those associated withcatastrophic mass extinction, are relatively abrupt and destructive.What sets one group apart from the other? Here I hypothesize thatperturbations of Earth's carbon cycle lead to mass extinction if theyexceed either a critical rate at long time scales or a critical sizeat short time scales. By analyzing 31 carbon-isotopic events duringthe last 542 million years, I identify the critical rate with a limitimposed by mass conservation. Further analysis identifies thecrossover timescale separating fast from slow events with thetimescale of the ocean's homeostatic response to a change in pH. Theproduct of the critical rate and the crossover timescale then yieldsthe critical size. The modern critical size for the marine carboncycle is roughly similar to the mass of carbon that human activitieswill likely have added to the oceans by the year 2100.
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Factual states of affairs – uniting diverging philosophical orientations ...
African Journals Online (AJOL)
The problem of persistence and change and the state of affairs that change can only be detected on the basis of constancy permeated the history of philosophy and the various academic disciplines, including the discipline of paleontology. The dominant pattern of the paleontological record, namely stasis, poses empirical ...
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Des Marais, D. J.
1998-01-01
Understanding our own early biosphere is essential to our search for life elsewhere, because life arose on Earth very early and rocky planets shared similar early histories. The biosphere arose before 3.8 Ga ago, was exclusively unicellular and was dominated by hyperthermophiles that utilized chemical sources of energy and employed a range of metabolic pathways for CO2 assimilation. Photosynthesis also arose very early. Oxygenic photosynthesis arose later but still prior to 2.7 Ga. The transition toward the modern global environment was paced by a decline in volcanic and hydrothermal activity. These developments allowed atmospheric O2 levels to increase. The O2 increase created new niches for aerobic life, most notably the more advanced Eukarya that eventually spawned the megascopic fauna and flora of our modern biosphere.
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Non-equilibrium thermodynamics, maximum entropy production and Earth-system evolution.
Kleidon, Axel
2010-01-13
The present-day atmosphere is in a unique state far from thermodynamic equilibrium. This uniqueness is for instance reflected in the high concentration of molecular oxygen and the low relative humidity in the atmosphere. Given that the concentration of atmospheric oxygen has likely increased throughout Earth-system history, we can ask whether this trend can be generalized to a trend of Earth-system evolution that is directed away from thermodynamic equilibrium, why we would expect such a trend to take place and what it would imply for Earth-system evolution as a whole. The justification for such a trend could be found in the proposed general principle of maximum entropy production (MEP), which states that non-equilibrium thermodynamic systems maintain steady states at which entropy production is maximized. Here, I justify and demonstrate this application of MEP to the Earth at the planetary scale. I first describe the non-equilibrium thermodynamic nature of Earth-system processes and distinguish processes that drive the system's state away from equilibrium from those that are directed towards equilibrium. I formulate the interactions among these processes from a thermodynamic perspective and then connect them to a holistic view of the planetary thermodynamic state of the Earth system. In conclusion, non-equilibrium thermodynamics and MEP have the potential to provide a simple and holistic theory of Earth-system functioning. This theory can be used to derive overall evolutionary trends of the Earth's past, identify the role that life plays in driving thermodynamic states far from equilibrium, identify habitability in other planetary environments and evaluate human impacts on Earth-system functioning. This journal is © 2010 The Royal Society
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From Suns to Life: A Chronological Approach to the History of Life on Earth
Gargaud, Muriel; López-García, Purificación; Martin, Hervé; Montmerle, Thierry; Pascal, Robert; Reisse, Jacques
2006-01-01
This review emerged from several interdisciplinary meetings and schools gathering a group of astronomers, geologists, biologists, and chemists, attempting to share their specialized knowledge around a common question: how did life emerge on Earth? Their ultimate goal was to provide some kind of answer as a prerequisite to an even more demanding question: is life universal? The resulting state-of-the-art articles were written by twenty-five scientists telling a not-so linear story, but on the contrary, highlighting problems, gaps, and controversies. Needless to say, this approach yielded no definitive answers to both questions. However, by adopting a chronological approach to the question of the emergence of life on Earth, the only place where we know for sure that life exists; it was possible to break down this question into several sub-topics that can be addressed by the different disciplines. The main chapters of this review present the formation and evolution of the solar system (3); the building of a habi...
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Magma Ocean Depth and Oxygen Fugacity in the Early Earth--Implications for Biochemistry.
Righter, Kevin
2015-09-01
A large class of elements, referred to as the siderophile (iron-loving) elements, in the Earth's mantle can be explained by an early deep magma ocean on the early Earth in which the mantle equilibrated with metallic liquid (core liquid). This stage would have affected the distribution of some of the classic volatile elements that are also essential ingredients for life and biochemistry - H, C, S, and N. Estimates are made of the H, C, S, and N contents of Earth's early mantle after core formation, considering the effects of variable temperature, pressure, oxygen fugacity, and composition on their partitioning. Assessment is made of whether additional, exogenous, sources are required to explain the observed mantle concentrations, and areas are identified where additional data and experimentation would lead to an improved understanding of this phase of Earth's history.
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Origin of the atmospheres of the earth and the planets
Energy Technology Data Exchange (ETDEWEB)
Chen, Z M
1978-06-01
From a systematic analysis of the whole history of the protoplanetary cloud and the observational facts of the earth's atmosphere, new theory is proposed on the origin of the atmospheres of the earth and the planets. For the earth-like planets, there were profound primordial atmospheres originated from the protoplanetary cloud by the accretion of the embryoes of planets. These primordial atmospheres has existed in a time scale of 10/sup 3/ to 10/sup 7/ years and were composed of chemically reducing gases. The presence of such a reducing atmosphere may be of great significance to the theories of cosmogony and the origin of life. The contents are as follows: the escape of the nebulae and the planetary atmospheres, the blowing-off of the atmospheres and the disspiation of gases driven by the solar wind, the accretion of gases by the planetary embryoes, the primordial atmospheres.
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The life history of Pseudomonas syringae: linking agriculture to earth system processes.
Morris, Cindy E; Monteil, Caroline L; Berge, Odile
2013-01-01
The description of the ecology of Pseudomonas syringae is moving away from that of a ubiquitous epiphytic plant pathogen to one of a multifaceted bacterium sans frontières in fresh water and other ecosystems linked to the water cycle. Discovery of the aquatic facet of its ecology has led to a vision of its life history that integrates spatial and temporal scales spanning billions of years and traversing catchment basins, continents, and the planet and that confronts the implication of roles that are potentially conflicting for agriculture (as a plant pathogen and as an actor in processes leading to rain and snowfall). This new ecological perspective has also yielded insight into epidemiological phenomena linked to disease emergence. Overall, it sets the stage for the integration of more comprehensive contexts of ecology and evolutionary history into comparative genomic analyses to elucidate how P. syringae subverts the attack and defense responses of the cohabitants of the diverse environments it occupies.
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The Pale Orange Dot: The Spectrum and Habitability of Hazy Archean Earth.
Arney, Giada; Domagal-Goldman, Shawn D; Meadows, Victoria S; Wolf, Eric T; Schwieterman, Edward; Charnay, Benjamin; Claire, Mark; Hébrard, Eric; Trainer, Melissa G
2016-11-01
Recognizing whether a planet can support life is a primary goal of future exoplanet spectral characterization missions, but past research on habitability assessment has largely ignored the vastly different conditions that have existed in our planet's long habitable history. This study presents simulations of a habitable yet dramatically different phase of Earth's history, when the atmosphere contained a Titan-like, organic-rich haze. Prior work has claimed a haze-rich Archean Earth (3.8-2.5 billion years ago) would be frozen due to the haze's cooling effects. However, no previous studies have self-consistently taken into account climate, photochemistry, and fractal hazes. Here, we demonstrate using coupled climate-photochemical-microphysical simulations that hazes can cool the planet's surface by about 20 K, but habitable conditions with liquid surface water could be maintained with a relatively thick haze layer (τ ∼ 5 at 200 nm) even with the fainter young Sun. We find that optically thicker hazes are self-limiting due to their self-shielding properties, preventing catastrophic cooling of the planet. Hazes may even enhance planetary habitability through UV shielding, reducing surface UV flux by about 97% compared to a haze-free planet and potentially allowing survival of land-based organisms 2.7-2.6 billion years ago. The broad UV absorption signature produced by this haze may be visible across interstellar distances, allowing characterization of similar hazy exoplanets. The haze in Archean Earth's atmosphere was strongly dependent on biologically produced methane, and we propose that hydrocarbon haze may be a novel type of spectral biosignature on planets with substantial levels of CO 2 . Hazy Archean Earth is the most alien world for which we have geochemical constraints on environmental conditions, providing a useful analogue for similar habitable, anoxic exoplanets. Key Words: Haze-Archean Earth-Exoplanets-Spectra-Biosignatures-Planetary habitability
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The origin of the moon and the early history of the earth - A chemical model. Part 1: The moon
International Nuclear Information System (INIS)
O'Neill, H. St.C.
1991-01-01
The chemical implications of a giant impact model for the origin of the moon are examined, both for the moon and for the earth. The Impactor is taken to be an approximately Mars-sized body. It is argued that the likeliest bulk chemical composition of the moon is quite similar to that of the earth's mantle, and that this composition may be explained in detail if about 80% of the moon came from the primitive earth's mantle after segregation of the earth's core. The other 20% of the moon is modelled as coming from (a) the Impactor, which is constrained to be an oxidized, probably undifferentiated body of roughly CI chondritic composition (on a volatile free basis) and (b) a late stage veneer, with a composition and oxidation state similar to that of the H-group ordinary chondrites. This latter component is the source of all the volatile elements in the moon, which failed to condense from the earth-and Impactor-derived materials; this component constitutes about 4% of the moon. It is argued that Mo may behave as a volatile element under the relatively oxidising conditions necessary for the condensation of the proto-moon. The model accounts satisfactorily for most of the siderophile elements, including Fe, Ni, Co, W, P, and Cu. The relatively well-constrained lunar abundances of V, Cr, and Mn are also accounted for; their depletion in the moon is inherited from the earth's mantle
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Natural history collections: A scientific treasure trove
,
2006-01-01
Natural history collections play an indispensable and often overlooked role in the conservation and management of our Nation’s flora and fauna. Scientific specimens housed in museum collections not only open an important window into the current and past diversity of life on Earth, but also play a vital role in fueling cutting-edge scientific research in many disciplines. The U.S. Geological Survey (USGS) Fort Collins Science Center (FORT) curates a collection of vertebrates from the Intermountain and Southwestern United States that is used by researchers from around the globe. As one of the largest Federal natural history collections in the western United States, the USGS specimen holdings offer unique opportunities to study the fauna of this incredibly diverse and unique region.
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Mining History and Prezent State of Medieval Mine Jeroným
Czech Academy of Sciences Publication Activity Database
Kaláb, Zdeněk; Lednická, Markéta; Hrubešová, E.
2008-01-01
Roč. 283, č. 1781 (2008), s. 61-71 ISSN 0372-9508 R&D Projects: GA ČR GA105/06/0068 Institutional research plan: CEZ:AV0Z30860518 Keywords : mining history * geomechanical monitoring * mining water Subject RIV: DC - Siesmology, Volcanology, Earth Structure www.wydawnictvopolitechniki.pl
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Directory of Open Access Journals (Sweden)
Shulan Su
2013-01-01
Full Text Available In this study, the reverse docking methodology was applied to predict the action targets and pathways of Shaofu Zhuyu decoction (SFZYD bioactive ingredients. Furthermore, Traditional Chinese Medicine (TCM cold coagulation blood stasis (CCBS syndrome was induced in female Sprague-Dawley rats with an ice-water bath and epinephrine, and SFZYD was used to treat CCBS syndrome. A metabolomic approach was used to evaluate changes in the metabolic profiles and to analyze the pharmacological mechanism of SFZYD actions. Twenty-three potential protein targets and 15 pathways were discovered, respectively; among these, pathways are associated with inflammation and immunological stress, hormone metabolism, coagulation function, and glycometabolism. There were also changes in the levels of endogenous metabolites of LysoPCs and glucuronides. Twenty endogenous metabolites were identified. Furthermore, the relative quantities of 6 endogenous metabolites in the plasma and 5 in the urine were significantly affected by SFZYD (P<0.05. The pharmacological mechanism of SFZYD was partially associated with glycerophospholipid metabolism and pentose and glucuronate interconversions. In conclusion, our findings demonstrated that TCM CCBS pattern induced by ice water and epinephrine was complex and related to multiple metabolic pathways. SFZYD did regulate the TCM CCBS by multitargets, and biomarkers and SFZYD should be used for the clinical treatment of CCBS syndrome.
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Gebauer, S; Grenfell, J L; Stock, J W; Lehmann, R; Godolt, M; von Paris, P; Rauer, H
2017-01-01
Understanding the evolution of Earth and potentially habitable Earth-like worlds is essential to fathom our origin in the Universe. The search for Earth-like planets in the habitable zone and investigation of their atmospheres with climate and photochemical models is a central focus in exoplanetary science. Taking the evolution of Earth as a reference for Earth-like planets, a central scientific goal is to understand what the interactions were between atmosphere, geology, and biology on early Earth. The Great Oxidation Event in Earth's history was certainly caused by their interplay, but the origin and controlling processes of this occurrence are not well understood, the study of which will require interdisciplinary, coupled models. In this work, we present results from our newly developed Coupled Atmosphere Biogeochemistry model in which atmospheric O 2 concentrations are fixed to values inferred by geological evidence. Applying a unique tool (Pathway Analysis Program), ours is the first quantitative analysis of catalytic cycles that governed O 2 in early Earth's atmosphere near the Great Oxidation Event. Complicated oxidation pathways play a key role in destroying O 2 , whereas in the upper atmosphere, most O 2 is formed abiotically via CO 2 photolysis. The O 2 bistability found by Goldblatt et al. ( 2006 ) is not observed in our calculations likely due to our detailed CH 4 oxidation scheme. We calculate increased CH 4 with increasing O 2 during the Great Oxidation Event. For a given atmospheric surface flux, different atmospheric states are possible; however, the net primary productivity of the biosphere that produces O 2 is unique. Mixing, CH 4 fluxes, ocean solubility, and mantle/crust properties strongly affect net primary productivity and surface O 2 fluxes. Regarding exoplanets, different "states" of O 2 could exist for similar biomass output. Strong geological activity could lead to false negatives for life (since our analysis suggests that reducing gases
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Educating the Public about Deep-Earth Science
Cronin, V. S.
2010-12-01
The nature of Earth’s interior is an active frontier of scientific research. Much of our current understanding of sub-crustal Earth is based on knowledge acquired in the last 2-3 decades, made possible by public funding and by dense seismic arrays, satellite remote sensing, increases in computer power that enable use of enhanced numerical techniques, improved theoretical and experimental knowledge of high PT mineral physics and chemistry, and a vigorous scientific community that has been trained to take advantage of these opportunities. An essential component of science is effective communication; therefore, providing for public education about science is a responsibility of the research community. Current public understanding of Earth’s interior is meager at best. In pre-college texts and in non-technical mass media, Earth's interior is typically visualized as an onion or baseball of concentric different-colored shells along whose upper surface "crustal" plates move like packages on conveyor belts of convecting mantle. Or the crust is thought to float on a molten mantle, as in the 19th century ideas of William Lowthian Green. Misconceptions about Earth that are brought to the undergraduate classroom must be confronted frankly and replaced by current understanding based on good science. Persistent ignorance has consequences. What do we want the public to know? First, the public should understand that knowledge of Earth's interior is important, not irrelevant. The public should know that deep-Earth processes result in Earth's dynamic magnetic field. Deep-Earth processes affect how radiation from the Sun reaches Earth, consequently affecting the atmosphere, the oceans, and the viability of life on Earth. The composition and differentiated structure of Earth's interior is a result of the early accretionary history of Earth and the Earth-Moon system. The public should also know that lithospheric tectonics, with all of its consequences (dynamic topography, volcanoes
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Wang, Yong; Li, Chun; Chang, Hong; Lu, Ling-Hui; Qiu, Qi; Ouyang, Yu-Lin; Yu, Jun-da; Guo, Shu-Zhen; Han, Jing; Wang, Wei
2016-08-01
To investigate the underlying metabolomic profifiling of coronary heart disease (CHD) with blood stasis syndrome (BSS). CHD model was induced by a nameroid constrictor in Chinese miniature swine. Fifteen miniature swine were randomly divided into a model group (n=9) and a control group (n=6), respectively according to arandom number table. After 4 weeks, plasma hemorheology was detected by automatic hemorheological analyzer, indices including hematocrit, plasma viscosity, blood viscosity, rigidity index and erythrocyte sedimentation rate; cardiac function was assessed by echocardiograph to detect left ventricular end-systolic diameter (LVED), left ventricular end-diastolic diameter (LVEDd), ejection fraction (EF), fractional shortening (FS) and other indicators. Gas chromatography coupled with mass spectrometry (GC-MS) and bioinformatics were applied to analyze spectra of CHD plasma with BSS. The results of hemorheology analysis showed signifificant changes in viscosity, with low shear whole blood viscosity being lower and plasma viscosity higher in the model group compared with the control group. Moreover, whole blood reduction viscosity at high shear rate and whole blood reduction viscosity at low shear rate increased signifificantly (P patterns involved were associated with dysfunction of energy metabolism including glucose and lipid disorders, especially in glycolysis/gluconeogenesis, galactose metabolism and adenosine-triphosphate-binding cassette transporters. Glucose metabolism and lipid metabolism disorders were the major contributors to the syndrome classifification of CHD with BSS.
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Earth's Paleomagnetosphere and Planetary Habitability
Tarduno, J. A.; Blackman, E. G.; Oda, H.; Bono, R. K.; Carroll-Nellenback, J.; Cottrell, R. D.; Nimmo, F.
2017-12-01
The geodynamo is thought to play an important role in protecting Earth's hydrosphere, vital for life as we know it, from loss due to the erosive potential of the solar wind. Here we consider the mechanisms and history of this shielding. A larger core dynamo magnetic field strength provides more pressure to abate the solar wind dynamic pressure, increasing the magnetopause radius. However, the larger magnetopause also implies a larger collecting area for solar wind flux during phases of magnetic reconnection. The important variable is not mass capture but energy transfer, which does not scale linearly with magnetosphere size. Moreover, the ordered field provides the magnetic topology for recapturing atmospheric components in the opposite hemisphere such that the net global loss might not be greatly affected. While a net protection role for magnetospheres is suggested, forcing by the solar wind will change with stellar age. Paleomagnetism utilizing the single silicate crystal approach, defines a relatively strong field some 3.45 billion years ago (the Paleoarchean), but with a reduced magnetopause of 5 Earth radii, implying the potential for some atmospheric loss. Terrestrial zircons from the Jack Hills (Western Australia) and other localities host magnetic inclusions, whose magnetization has now been recorded by a new generation of ultra-sensitive 3-component SQUID magnetometer (U. Rochester) and SQUID microscope (GSJ/AIST). Paleointensity data suggest the presence of a terrestrial dynamo and magnetic shielding for Eoarchean to Hadean times, at ages as old as 4.2 billion years ago. However, the magnetic data suggest that for intervals >100,000 years long, magnetopause standoff distances may have reached 3 to 4 Earth radii or less. The early inception of the geodynamo, which probably occurred shortly after the lunar-forming impact, its continuity, and an early robust hydrosphere, appear to be key ingredients for Earth's long-term habitability.
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A History of Regression and Related Model-Fitting in the Earth Sciences (1636?-2000)
International Nuclear Information System (INIS)
Howarth, Richard J.
2001-01-01
The (statistical) modeling of the behavior of a dependent variate as a function of one or more predictors provides examples of model-fitting which span the development of the earth sciences from the 17th Century to the present. The historical development of these methods and their subsequent application is reviewed. Bond's predictions (c. 1636 and 1668) of change in the magnetic declination at London may be the earliest attempt to fit such models to geophysical data. Following publication of Newton's theory of gravitation in 1726, analysis of data on the length of a 1 o meridian arc, and the length of a pendulum beating seconds, as a function of sin 2 (latitude), was used to determine the ellipticity of the oblate spheroid defining the Figure of the Earth. The pioneering computational methods of Mayer in 1750, Boscovich in 1755, and Lambert in 1765, and the subsequent independent discoveries of the principle of least squares by Gauss in 1799, Legendre in 1805, and Adrain in 1808, and its later substantiation on the basis of probability theory by Gauss in 1809 were all applied to the analysis of such geodetic and geophysical data. Notable later applications include: the geomagnetic survey of Ireland by Lloyd, Sabine, and Ross in 1836, Gauss's model of the terrestrial magnetic field in 1838, and Airy's 1845 analysis of the residuals from a fit to pendulum lengths, from which he recognized the anomalous character of measurements of gravitational force which had been made on islands. In the early 20th Century applications to geological topics proliferated, but the computational burden effectively held back applications of multivariate analysis. Following World War II, the arrival of digital computers in universities in the 1950s facilitated computation, and fitting linear or polynomial models as a function of geographic coordinates, trend surface analysis, became popular during the 1950-60s. The inception of geostatistics in France at this time by Matheron had its
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A Tale of Two Earths: Reconciling the Lunar and Terrestrial Hadean Records
Boehnke, Patrick
Studying early Earth history is complicated by the fact that the rock record doesn't extend past 4 Ga and our only record for the Hadean (>4 Ga) comes to us from detrital zircons from the Jack Hills in Western Australia. The Hadean zircon record extends back to almost 4.4 Ga and has revealed that the early Earth may have had liquid water, a felsic crust, plate boundary interactions, and possibly a biosphere. On the other hand, analyses of lunar and meteoritic samples are used to argue for a hellish Hadean Earth where frequent, large impactors repeatedly destroyed the crust. Indeed, these two models stand in direct contradiction. The focus of this thesis is to examine the evidence for these two models and ultimately propose a reconciliation based on a new interpretation of the chronology of the lunar samples used to constrain the impact history into the early Earth-Moon system. In order to improve the understanding of zircon crystallization in igneous settings, we undertook experimental studies of zircon saturation which were analyzed using a novel ion imaging approach by a secondary ion mass spectrometer. This study confirmed the original model for zircon saturation, that it is a function of only temperature, melt composition, and Zr content. Indeed, the primary implication for the early Earth from this work is that zircons are much more likely to crystallize in a felsic rather than mafic magma and therefore simply the existence of Hadean zircons suggests a high likelihood for felsic Hadean magmatism. The majority of the thesis focuses on the interpretation of 40 Ar/39Ar ages of lunar and meteorite samples, specifically with regards to impact histories derived from compilations of such ages. The primary complication with lunar and meteorite 40Ar/ 39Ar ages is that the vast majority show evidence for later disturbances due to diffusive loss of 40Ar. To try and extract meaningful thermal histories from these samples, we undertook investigations of samples from Apollo
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Transdisciplinary Perspectives in Bioethics: A Co-evolutionary Introduction from the Big History
Directory of Open Access Journals (Sweden)
Javier Collado-Ruano
2016-10-01
Full Text Available The main objective of this work is to expand the bioethics notion expressed in the Article 17th of the Universal Declaration on Bioethics and Human Rights, concerning the interconnections between human beings and other life forms. For this purpose, it is combined the transdisciplinary methodology with the theoretical framework of the “Big History” to approach the co-evolutionary phenomena that life is developing on Earth for some 3.8 billion years. As a result, the study introduces us to the unification, integration and inclusion of the history of the universe, the solar system, Earth, and life with the history of human beings. In conclusion, I consider to safeguard the cosmic miracle that represents the emergence of life we must adopt new transdisciplinary perspectives into bioethics to address the ecosystem complexity of co-evolutionary processes of life on Gaia as a whole.
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Pringle, M. S.; Kamerer, B.; Vugrin, M.; Miller, M.
2009-12-01
Earth Science II: The Solid Earth -- Earth History and Planetary Science -- is the second of two Earth Science courses, and one of eleven graduate level science Contextualized Content Courses (CCC), that have been developed by the Boston Science Partnership as part of an NSF-funded Math Science Partnership program. A core goal of these courses is to provide high level science content to middle and high school teachers while modeling good instructional practices directly tied to the Boston Public Schools and Massachusetts science curriculum frameworks. All of these courses emphasize hands-on, lab-based, inquiry-driven, student-centered lessons. The Earth Science II team aimed to strictly adhere to ABC (Activity Before Concept) and 5E/7E models of instruction, and limited lecture or teacher-centered instruction to the later “Explanation” stages of all lessons. We also introduced McNeill and Krajick’s Claim-Evidence-Reasoning (CER) model of scientific explanation for middle school classroom discourse, both as a powerful scaffold leading to higher levels of accountable talk in the classroom, and to model science as a social construct. Daily evaluations, dutifully filled out by the course participants and diligently read by the course instructors, were quite useful in adapting instruction to the needs of the class on a real-time basis. We find the structure of the CCC teaching teams - university-based faculty providing expert content knowledge, K-12-based faculty providing age appropriate pedagogies and specific links to the K-12 curriculum - quite a fruitful, two-way collaboration. From the students’ perspective, one of the most useful takeaways from the university-based faculty was “listening to experts model out loud how they reason,” whereas some of the more practical takeaways (i.e., lesson components directly portable to the classroom?) came from the K-12-based faculty. The main takeaways from the course as a whole were the promise to bring more hands
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Cytosine deamination and the precipitous decline of spontaneous mutation during Earth's history.
Lewis, Charles A; Crayle, Jesse; Zhou, Shuntai; Swanstrom, Ronald; Wolfenden, Richard
2016-07-19
The hydrolytic deamination of cytosine and 5-methylcytosine residues in DNA appears to contribute significantly to the appearance of spontaneous mutations in microorganisms and in human disease. In the present work, we examined the mechanism of cytosine deamination and the response of the uncatalyzed reaction to changing temperature. The positively charged 1,3-dimethylcytosinium ion was hydrolyzed at a rate similar to the rate of acid-catalyzed hydrolysis of 1-methylcytosine, for which it furnishes a satisfactory kinetic model and a probable mechanism. In agreement with earlier reports, uncatalyzed deamination was found to proceed at very similar rates for cytosine, 1-methylcytosine, cytidine, and cytidine 5'-phosphate, and also for cytosine residues in single-stranded DNA generated from a phagemid, in which we sequenced an insert representing the gene of the HIV-1 protease. Arrhenius plots for the uncatalyzed deamination of cytosine were linear over the temperature range from 90 °C to 200 °C and indicated a heat of activation (ΔH(‡)) of 23.4 ± 0.5 kcal/mol at pH 7. Recent evidence indicates that the surface of the earth has been cool enough to support life for more than 4 billion years and that life has been present for almost as long. If the temperature at Earth's surface is assumed to have followed Newton's law of cooling, declining exponentially from 100 °C to 25 °C during that period, then half of the cytosine-deaminating events per unit biomass would have taken place during the first 0.2 billion years, and <99.4% would have occurred during the first 2 billion years.
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Tidal Friction in the Earth-Moon System and Laplace Planes: Darwin Redux
Rubincam, David P.
2015-01-01
The dynamical evolution of the Earth-Moon system due to tidal friction is treated here. George H. Darwin used Laplace planes (also called proper planes) in his study of tidal evolution. The Laplace plane approach is adapted here to the formalisms of W.M. Kaula and P. Goldreich. Like Darwin, the approach assumes a three-body problem: Earth, Moon, and Sun, where the Moon and Sun are point-masses. The tidal potential is written in terms of the Laplace plane angles. The resulting secular equations of motion can be easily integrated numerically assuming the Moon is in a circular orbit about the Earth and the Earth is in a circular orbit about the Sun. For Earth-Moon distances greater than 10 Earth radii, the Earth's approximate tidal response can be characterized with a single parameter, which is a ratio: a Love number times the sine of a lag angle divided by another such product. For low parameter values it can be shown that Darwin's low-viscosity molten Earth, M. Ross's and G. Schubert's model of an Earth near melting, and Goldreich's equal tidal lag angles must all give similar histories. For higher parameter values, as perhaps has been the case at times with the ocean tides, the Earth's obliquity may have decreased slightly instead of increased once the Moon's orbit evolved further than 50 Earth radii from the Earth, with possible implications for climate. This is contrast to the other tidal friction models mentioned, which have the obliquity always increasing with time. As for the Moon, its orbit is presently tilted to its Laplace plane by 5.2deg. The equations do not allow the Moon to evolve out of its Laplace plane by tidal friction alone, so that if it was originally in its Laplace plane, the tilt arose with the addition of other mechanisms, such as resonance passages.
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AN ANCIENT EXTRASOLAR SYSTEM WITH FIVE SUB-EARTH-SIZE PLANETS
Energy Technology Data Exchange (ETDEWEB)
Campante, T. L.; Davies, G. R.; Chaplin, W. J.; Handberg, R. [School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Barclay, T.; Huber, D.; Burke, C. J.; Quintana, E. V. [NASA Ames Research Center, Moffett Field, CA 94035 (United States); Swift, J. J. [Department of Astronomy and Department of Planetary Science, California Institute of Technology, MC 249-17, Pasadena, CA 91125 (United States); Adibekyan, V. Zh. [Centro de Astrofísica, Universidade do Porto, Rua das Estrelas, 4150-762 Porto (Portugal); Cochran, W. [Department of Astronomy and McDonald Observatory, The University of Texas at Austin, TX 78712-1205 (United States); Isaacson, H. [Astronomy Department, University of California, Berkeley, CA 94720 (United States); Silva Aguirre, V.; Christensen-Dalsgaard, J.; Metcalfe, T. S.; Bedding, T. R. [Stellar Astrophysics Centre (SAC), Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C (Denmark); Ragozzine, D. [Department of Physics and Space Sciences, Florida Institute of Technology, 150 West University Boulevard, Melbourne, FL 32901 (United States); Riddle, R. [Division of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, CA 91125 (United States); Baranec, C. [Institute for Astronomy, University of Hawai' i at Mānoa, Hilo, HI 96720-2700 (United States); Basu, S., E-mail: campante@bison.ph.bham.ac.uk [Department of Astronomy, Yale University, New Haven, CT 06520 (United States); and others
2015-02-01
The chemical composition of stars hosting small exoplanets (with radii less than four Earth radii) appears to be more diverse than that of gas-giant hosts, which tend to be metal-rich. This implies that small, including Earth-size, planets may have readily formed at earlier epochs in the universe's history when metals were more scarce. We report Kepler spacecraft observations of Kepler-444, a metal-poor Sun-like star from the old population of the Galactic thick disk and the host to a compact system of five transiting planets with sizes between those of Mercury and Venus. We validate this system as a true five-planet system orbiting the target star and provide a detailed characterization of its planetary and orbital parameters based on an analysis of the transit photometry. Kepler-444 is the densest star with detected solar-like oscillations. We use asteroseismology to directly measure a precise age of 11.2 ± 1.0 Gyr for the host star, indicating that Kepler-444 formed when the universe was less than 20% of its current age and making it the oldest known system of terrestrial-size planets. We thus show that Earth-size planets have formed throughout most of the universe's 13.8 billion year history, leaving open the possibility for the existence of ancient life in the Galaxy. The age of Kepler-444 not only suggests that thick-disk stars were among the hosts to the first Galactic planets, but may also help to pinpoint the beginning of the era of planet formation.
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AN ANCIENT EXTRASOLAR SYSTEM WITH FIVE SUB-EARTH-SIZE PLANETS
International Nuclear Information System (INIS)
Campante, T. L.; Davies, G. R.; Chaplin, W. J.; Handberg, R.; Barclay, T.; Huber, D.; Burke, C. J.; Quintana, E. V.; Swift, J. J.; Adibekyan, V. Zh.; Cochran, W.; Isaacson, H.; Silva Aguirre, V.; Christensen-Dalsgaard, J.; Metcalfe, T. S.; Bedding, T. R.; Ragozzine, D.; Riddle, R.; Baranec, C.; Basu, S.
2015-01-01
The chemical composition of stars hosting small exoplanets (with radii less than four Earth radii) appears to be more diverse than that of gas-giant hosts, which tend to be metal-rich. This implies that small, including Earth-size, planets may have readily formed at earlier epochs in the universe's history when metals were more scarce. We report Kepler spacecraft observations of Kepler-444, a metal-poor Sun-like star from the old population of the Galactic thick disk and the host to a compact system of five transiting planets with sizes between those of Mercury and Venus. We validate this system as a true five-planet system orbiting the target star and provide a detailed characterization of its planetary and orbital parameters based on an analysis of the transit photometry. Kepler-444 is the densest star with detected solar-like oscillations. We use asteroseismology to directly measure a precise age of 11.2 ± 1.0 Gyr for the host star, indicating that Kepler-444 formed when the universe was less than 20% of its current age and making it the oldest known system of terrestrial-size planets. We thus show that Earth-size planets have formed throughout most of the universe's 13.8 billion year history, leaving open the possibility for the existence of ancient life in the Galaxy. The age of Kepler-444 not only suggests that thick-disk stars were among the hosts to the first Galactic planets, but may also help to pinpoint the beginning of the era of planet formation
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Directory of Open Access Journals (Sweden)
L. Lareo
2005-12-01
Full Text Available Dada la importancia del receptor ionotrópico de glutamato activado por N-Metil-D-Aspartato en los procesos de aprendizaje y la formación de la memoria mediados por el transporte de calcio a través del canal asociado a dicho receptor resulta importante desarrollar modelos que permitan comprender la homeóstasis que le permite a la neurona manejar incrementos en el flujo de dicho catión sin llegar a desarrollar procesos necróticos ni apoptóticos. Este trabajo presenta una sencilla simulación de parte de los procesos metabólicos asociados al receptor como un paso inicial para comprender los mecanismos subyacentes al aprendizaje y memoria.
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An Earth-sized planet with an Earth-like density.
Pepe, Francesco; Cameron, Andrew Collier; Latham, David W; Molinari, Emilio; Udry, Stéphane; Bonomo, Aldo S; Buchhave, Lars A; Charbonneau, David; Cosentino, Rosario; Dressing, Courtney D; Dumusque, Xavier; Figueira, Pedro; Fiorenzano, Aldo F M; Gettel, Sara; Harutyunyan, Avet; Haywood, Raphaëlle D; Horne, Keith; Lopez-Morales, Mercedes; Lovis, Christophe; Malavolta, Luca; Mayor, Michel; Micela, Giusi; Motalebi, Fatemeh; Nascimbeni, Valerio; Phillips, David; Piotto, Giampaolo; Pollacco, Don; Queloz, Didier; Rice, Ken; Sasselov, Dimitar; Ségransan, Damien; Sozzetti, Alessandro; Szentgyorgyi, Andrew; Watson, Christopher A
2013-11-21
Recent analyses of data from the NASA Kepler spacecraft have established that planets with radii within 25 per cent of the Earth's (R Earth symbol) are commonplace throughout the Galaxy, orbiting at least 16.5 per cent of Sun-like stars. Because these studies were sensitive to the sizes of the planets but not their masses, the question remains whether these Earth-sized planets are indeed similar to the Earth in bulk composition. The smallest planets for which masses have been accurately determined are Kepler-10b (1.42 R Earth symbol) and Kepler-36b (1.49 R Earth symbol), which are both significantly larger than the Earth. Recently, the planet Kepler-78b was discovered and found to have a radius of only 1.16 R Earth symbol. Here we report that the mass of this planet is 1.86 Earth masses. The resulting mean density of the planet is 5.57 g cm(-3), which is similar to that of the Earth and implies a composition of iron and rock.
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Vahidkhah, Koohyar; Azadani, Ali N
2017-06-14
Leaflet thrombosis following transcatheter aortic valve replacement (TAVR) and Valve-in-Valve (ViV) procedures has been increasingly recognized. This study aimed to investigate the effect of positioning of the transcatheter aortic valve (TAV) in ViV setting on the flow dynamics aspect of post-ViV thrombosis by quantifying the blood stasis in the intra-annular and supra-annular settings. To that end, two idealized computational models, representing ViV intra-annular and supra-annular positioning of a TAV were developed in a patient-specific geometry. Three-dimensional flow fields were then obtained via fluid-solid interaction modeling to study the difference in blood residence time (BRT) on the TAV leaflets in the two settings. At the end of diastole, a strip of high BRT (⩾1.2s) region was observed on the TAV leaflets in the ViV intra-annular positioning at the fixed boundary where the leaflets are attached to the frame. Such a high BRT region was absent on the TAV leaflets in the supra-annular positioning. The maximum value of BRT on the surface of non-, right, and left coronary leaflets of the TAV in the supra-annular positioning were 53%, 11%, and 27% smaller compared to the intra-annular positioning, respectively. It was concluded that the geometric confinement of TAV by the leaflets of the failed bioprosthetic valve in ViV intra-annular positioning increases the BRT on the leaflets and may act as a permissive factor in valvular thrombosis. The absence of such a geometric confinement in the ViV supra-annular positioning leads to smaller BRT and subsequently less likelihood of leaflet thrombosis. Copyright © 2017 Elsevier Ltd. All rights reserved.
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International Nuclear Information System (INIS)
Omata, Takayuki; Saito, Kazuhiro; Kotake, Fumio; Mizokami, Yuji; Matsuoka, Takeshi; Abe, Kimihiko
2002-01-01
Dynamic MR cholangiography was conducted on patients with cholelithiasis or choledocholithiasis who had consumed a fatty test meal (Molyork) and the cystic contractility and dynamics of biliary stasis was evaluated. The subjects were 25 with intracystic cholelithiasis, 10 with choledocholithiasis and 10 normal controls. For an imaging sequence, the rapid acquisition with relaxation enhancement (RARE) method was employed and imaging was conducted for 40 min (every 30 s following Molyork administration) without breath-holding. The gallbladder contraction ratio was computed and the contractile ratio for the common bile duct was calculated. To determine the bile flow to the duodenum, the high-intensity signal, indicating the flow from the lower common bile duct, and perfusion of the duodenum were observed in dynamic mode on the monitor with the naked eye and interpreted as positive bile flow. The frequency of this flow was visually monitored. The gallbladder contractile ratio was significantly reduced in patients with cholelithiasis or choledocholithiasis compared with the controls. In a comparison with the normal controls, no sequential changes were noted in the mean contractile ratio of the common bile duct of the patients with cholelithiasis or choledocholithiasis. The mean frequency of bile flow observed for each 40 min period was 13±2.4, 6±2.2, and 4±1.3 times for the controls, those with intracystic cholelithiasis, and those with choledocholithiasis, respectively. Compared with the controls, the latter two patient groups showed evident reductions in the frequency of bile flow to the duodenum (p<0.001). Dynamic MRC combined with Molyork loading makes it possible to compute cystic contractile ratios and perform a dynamic examination of bile flow under non-invasive, near-physiological conditions. (author)
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Towards earth AntineutRino TomograpHy (EARTH)
De Meijer, R. J.; Smit, F. D.; Brooks, F. D.; Fearick, R. W.; Wortche, H. J.; Mantovani, F.
2006-01-01
The programme Earth AntineutRino TomograpHy (EARTH) proposes to build ten underground facilities each hosting a telescope. Each telescope consists of many detector modules, to map the radiogenic heat sources deep in the interior of the Earth by utilising direction sensitive geoneutrino detection.
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Histories of terrestrial planets
International Nuclear Information System (INIS)
Benes, K.
1981-01-01
The uneven historical development of terrestrial planets - Mercury, Venus, Earth, Moon and Mars - is probably due to the differences in their size, weight and rotational dynamics in association with the internal planet structure, their distance from the Sun, etc. A systematic study of extraterrestrial planets showed that the time span of internal activity was not the same for all bodies. It is assumed that the initial history of all terrestrial planets was marked with catastrophic events connected with the overall dynamic development of the solar system. In view of the fact that the cores of small terrestrial bodies cooled quicker, their geological development almost stagnated after two or three thousand million years. This is what probably happened to the Mercury and the Moon as well as the Mars. Therefore, traces of previous catastrophic events were preserved on the surface of the planets. On the other hand, the Earth is the most metamorphosed terrestrial planet and compared to the other planets appears to be atypical. Its biosphere is significantly developed as well as the other shell components, its hydrosphere and atmosphere, and its crust is considerably differentiated. (J.P.)
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Using GRIDVIEW to Better Understand the Early Bombardment History of the Moon, Mars and Earth
Frey, Herbert
2012-01-01
) on the Moon (Frey and Burgess, 2012, this meeting), with obvious implications for the early bombardment history of the Earth.
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Climate History and the Modern World
Riebsame, William E.
H. H. Lamb's latest book on the earth's changing climate is a carefully crafted work covering four areas: the physical basis of climate and climate change, the methods of climate reconstruction, the history of climate since the height of the last glaciation, and the impact of climate on human affairs. The book will be of particular interest to three groups. Atmospheric scientists interested in the long history of climate behavior (but perhaps overwhelmed by Lamb's all-encompassing work on the topic, Climate: Past, Present and Future, vol. II, Methuen, New York), will find Climate History and the Modern World to be a good titration of the fuller work. Scientists in other fields, including social scientists grappling with issues of climate-society interaction, will find the book a good entree into the field. Finally, Lamb himself suggests that the book will be useful to resource managers and other decision makers trying to avoid negative climate impacts. With this last audience in mind, no doubt, Lamb has chosen a style that eschews extensive footnoting and references (though sufficient citations are included to lead to further information). This works quite well and seems reasonable in view of his carefully documented previous writings.
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VenSAR on EnVision: Taking earth observation radar to Venus
Ghail, Richard C.; Hall, David; Mason, Philippa J.; Herrick, Robert R.; Carter, Lynn M.; Williams, Ed
2018-02-01
Venus should be the most Earth-like of all our planetary neighbours: its size, bulk composition and distance from the Sun are very similar to those of Earth. How and why did it all go wrong for Venus? What lessons can be learned about the life story of terrestrial planets in general, in this era of discovery of Earth-like exoplanets? Were the radically different evolutionary paths of Earth and Venus driven solely by distance from the Sun, or do internal dynamics, geological activity, volcanic outgassing and weathering also play an important part? EnVision is a proposed ESA Medium class mission designed to take Earth Observation technology to Venus to measure its current rate of geological activity, determine its geological history, and the origin and maintenance of its hostile atmosphere, to understand how Venus and Earth could have evolved so differently. EnVision will carry three instruments: the Venus Emission Mapper (VEM); the Subsurface Radar Sounder (SRS); and VenSAR, a world-leading European phased array synthetic aperture radar that is the subject of this article. VenSAR will obtain images at a range of spatial resolutions from 30 m regional coverage to 1 m images of selected areas; an improvement of two orders of magnitude on Magellan images; measure topography at 15 m resolution vertical and 60 m spatially from stereo and InSAR data; detect cm-scale change through differential InSAR, to characterise volcanic and tectonic activity, and estimate rates of weathering and surface alteration; and characterise of surface mechanical properties and weathering through multi-polar radar data. These data will be directly comparable with Earth Observation radar data, giving geoscientists unique access to an Earth-sized planet that has evolved on a radically different path to our own, offering new insights on the Earth-sized exoplanets across the galaxy.
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The computational future for climate and Earth system models: on the path to petaflop and beyond.
Washington, Warren M; Buja, Lawrence; Craig, Anthony
2009-03-13
The development of the climate and Earth system models has had a long history, starting with the building of individual atmospheric, ocean, sea ice, land vegetation, biogeochemical, glacial and ecological model components. The early researchers were much aware of the long-term goal of building the Earth system models that would go beyond what is usually included in the climate models by adding interactive biogeochemical interactions. In the early days, the progress was limited by computer capability, as well as by our knowledge of the physical and chemical processes. Over the last few decades, there has been much improved knowledge, better observations for validation and more powerful supercomputer systems that are increasingly meeting the new challenges of comprehensive models. Some of the climate model history will be presented, along with some of the successes and difficulties encountered with present-day supercomputer systems.
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Lee, C. T.
2016-12-01
Most of Earth's continents today are above sea level, but the presence of thick packages of ancient sediments on top of the stable cores of continents indicates that continents must have been submerged at least once in their past. Elevations of continents are controlled by the interplay between crustal thickness, mantle root thickness and the temperature of the ambient convecting mantle. The history of a continent begins with mountain building through magmatic or tectonic crustal thickening, during which exhumation of deep-seated igneous and metamorphic rocks are highest. Mountain building is followed by a long interval of subsidence as a result of continued, but decreasing erosion and thermal relaxation, the latter in the form of a growing thermal boundary layer. Subsidence is manifest first as a boring interval in which no sedimentary record is preserved, followed by continent-scale submergence wherein sediments are deposited directly on deep-seated igneous/metamorphic basement, generating a major disconformity. The terminal resting elevation of a mature continent, however, is defined by the temperature of the ambient convecting mantle: below sea level when the mantle is hot and above sea level when the mantle is cold. Using thermobarometric constraints on secular cooling of Earth's mantle, our results suggest that Earth, for most of its history, must have been a water world, with regions of land confined to narrow orogenic belts and oceans characterized by deep basins and shallow continental seas, the latter serving as repositories of sediments and key redox-sensitive biological nutrients, such as phosphorous. Cooling of the Earth led to the gradual and irreversible rise of the continents, culminating in rapid emergence, through fits and starts and possible instabilities in climate, between 500-1000 Ma. Such emergence fundamentally altered marine biogeochemical cycling, continental weathering and the global hydrologic cycle, defining the backdrop for the
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Effects of megascale eruptions on Earth and Mars
Thordarson, T.; Rampino, M.; Keszthelyi, L.P.; Self, S.
2009-01-01
Volcanic features are common on geologically active earthlike planets. Megascale or "super" eruptions involving >1000 Gt of magma have occurred on both Earth and Mars in the geologically recent past, introducing prodigious volumes of ash and volcanic gases into the atmosphere. Here we discuss felsic (explosive) and mafi c (flood lava) supereruptions and their potential atmospheric and environmental effects on both planets. On Earth, felsic supereruptions recur on average about every 100-200,000 years and our present knowledge of the 73.5 ka Toba eruption implies that such events can have the potential to be catastrophic to human civilization. A future eruption of this type may require an unprecedented response from humankind to assure the continuation of civilization as we know it. Mafi c supereruptions have resulted in atmospheric injection of volcanic gases (especially SO2) and may have played a part in punctuating the history of life on Earth. The contrast between the more sustained effects of flood basalt eruptions (decades to centuries) and the near-instantaneous effects of large impacts (months to years) is worthy of more detailed study than has been completed to date. Products of mafi c supereruptions, signifi cantly larger than known from the geologic record on Earth, are well preserved on Mars. The volatile emissions from these eruptions most likely had global dispersal, but the effects may not have been outside what Mars endures even in the absence of volcanic eruptions. This is testament to the extreme variability of the current Martian atmosphere: situations that would be considered catastrophic on Earth are the norm on Mars. ?? 2009 The Geological Society of America.
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Rare earth metals, rare earth hydrides, and rare earth oxides as thin films
International Nuclear Information System (INIS)
Gasgnier, M.
1980-01-01
The review deals with pure rare earth materials such as rare earth metals, rare earth hydrides, and rare earth oxides as thin films. Several preparation techniques, control methods, and nature of possible contaminations of thin films are described. These films can now be produced in an extremely well-known state concerning chemical composition, structure and texture. Structural, electric, magnetic, and optical properties of thin films are studied and discussed in comparison with the bulk state. The greatest contamination of metallic rare earth thin films is caused by reaction with hydrogen or with water vapour. The compound with an f.c.c. structure is the dihydride LnH 2 (Ln = lanthanides). The oxygen contamination takes place after annealing at higher temperatures. Then there appears a compound with a b.c.c. structure which is the C-type sesquioxide C-Ln 2 O 3 . At room atmosphere dihydride light rare earth thin films are converted to hydroxide Ln(OH) 3 . For heavy rare earth thin films the oxinitride LnNsub(x)Osub(y) is observed. The LnO-type compound was never seen. The present review tries to set the stage anew for the investigations to be undertaken in the future especially through the new generations of electron microscopes
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Hart, R.; Hogan, L.
1985-01-01
Recent noble gas studies suggests the Earth's atmosphere outgassed from the Earth's upper mantle synchronous with sea floor spreading, ocean ridge hydrothermal activity and the formation of continents by partial melting in subduction zones. The evidence for formation of the atmosphere by outgassing of the mantle is the presence of radionuclides H3.-4, Ar-040 and 136 Xe-136 in the atmosphere that were produced from K-40, U and Th in the mantle. How these radionuclides were formed is reviewed.
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Highlights and impacts of the International Year of Planet Earth in Hungary
Szarka, László; Ádám, József; Brezsnyánszky, Károly; Haas, János; Kakas, Kristóf; Koppán, András.
2010-05-01
IYPE activities of various geo-science associations, universities, research institutes and private companies in Hungary (www.foldev.hu) have been successfully coordinated by the Hungarian National Committee, which was established by the Hungarian Academy of Sciences, the UNESCO- and the IUGS National Committees. The National Launch Event (April 17, 2008) was followed with a four-days long "Earth Science Fair" at the Hungarian Natural History Museum in Budapest. The IYPE was even briefly reviewed in the Hungarian Parliament. The Science Festival, organized annually by the Hungarian Academy of Sciences, in 2008 had a special IYPE-inspired slogan: "Science for the Habitable Earth", where lectures were held about the modern content of the Greek Classical Elements ("earth", "water", "air" and "fire", that is energy) and about the Humanity. In 2008/2009 numerous publications (including the Hungarian version of the IYPE booklet series, under the title GEO-FIFIKA, the Természet Világa special issue in February 2009, the IYPE number of Földrajzi Közlemények (Geographical Communications), and the "Geological Map of Hungary for Tourists" were produced. Throughout the country, symposia (e.g. HUNGEO 2008, ELGI 100, MÁFI 140, Geotourism Symposium in October 2009), several contests (Hungarian Television "Delta", Élet és Tudomány on the occasion of the UN year, and the annual contests starting in 2007 at Miskolc University), film shows (e.g., the movie "Another Planet") and other performances (e.g. End of the Ice Age in Hungarian Natural History Museum) were organized, with modest but increasing media coverage. The worldwide premier of the Planet Earth TV took place in Hungary, on the occasion of the IAGA 11th Scientific Assembly (August 23-30, 2009, www.iaga2009sopron.hu). One of our conferences ("Earth and Heaven - Geology and Theology") pointed out that there should be no conflict between science and religion, either in the fields of Earth's history or evolution
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Bayesian analysis of the astrobiological implications of life's early emergence on Earth.
Spiegel, David S; Turner, Edwin L
2012-01-10
Life arose on Earth sometime in the first few hundred million years after the young planet had cooled to the point that it could support water-based organisms on its surface. The early emergence of life on Earth has been taken as evidence that the probability of abiogenesis is high, if starting from young Earth-like conditions. We revisit this argument quantitatively in a bayesian statistical framework. By constructing a simple model of the probability of abiogenesis, we calculate a bayesian estimate of its posterior probability, given the data that life emerged fairly early in Earth's history and that, billions of years later, curious creatures noted this fact and considered its implications. We find that, given only this very limited empirical information, the choice of bayesian prior for the abiogenesis probability parameter has a dominant influence on the computed posterior probability. Although terrestrial life's early emergence provides evidence that life might be abundant in the universe if early-Earth-like conditions are common, the evidence is inconclusive and indeed is consistent with an arbitrarily low intrinsic probability of abiogenesis for plausible uninformative priors. Finding a single case of life arising independently of our lineage (on Earth, elsewhere in the solar system, or on an extrasolar planet) would provide much stronger evidence that abiogenesis is not extremely rare in the universe.
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Directory of Open Access Journals (Sweden)
J. F. Noguera Aguilar
2005-11-01
Full Text Available Aim: to analyze qualitative short-time results of a new program for multidisciplinary liver evaluation in complex cases of liver metastasis from colorectal cancer. Patients and methods: 40 clinical consecutive evaluations with liver metastasis assessed for major liver resection by a multidisplinary specialist committee. Complementary explorations performed included CT and ultrasounds, and MRI or PET for doubtful cases. Liver resection was made in a single operation or two-stage hepatectomy, or combined with other techniques. Results: postoperative mortality at 30 days was 4%. Complications occurred in 28%, with surgical wound infection being most frequent (20%; 16.6% of resections were transfused, with a mean volume of 1000 ml. Two patients needed reoperation -one for an intraperitoneal abscess and one for bile-duct stenosis. Percentage of global relapse was 36%, with 26% of relapses out of the liver. Actuarial survival at one year follow-up was 90%, and 82% at two years; 64% of patients remain free of disease two years after the operation. Conclusions: programs for liver resection for colorectal cancer metastasis may be implemented by multidisciplinary teams of recent setup. There is a need to evaluate own results and then compare them with a standard of quality previously reported.Objetivo: valorar los resultados cualitativos a corto y medio plazo de un programa de reciente implantación de evaluación hepática multidisciplinar de casos complejos de metástasis hepáticas de cáncer colorrectal. Pacientes y métodos: cuarenta evaluaciones clínicas consecutivas de pacientes con metástasis hepáticas de cáncer colorrectal valorados para resección hepática mayor, realizadas por un comité multidisciplinar de especialistas. Las exploraciones complementarias practicadas fueron TAC trifásica y ecografía intraoperatoria, junto a RMN y/o PET en casos de dudas. La resección hepática se podía realizar como gesto único o bien en dos tiempos y
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Transforming Water Management: an Emerging Promise of Integrated Earth Observations
Lawford, R. G.
2011-12-01
Throughout its history, civilization has relied on technology to facilitate many of its advances. New innovations and technologies have often provided strategic advantages that have led to transformations in institutions, economies and ultimately societies. Observational and information technologies are leading to significant developments in the water sector. After a brief introduction tracing the role of observational technologies in the areas of hydrology and water cycle science, this talk explores the existing and potential contributions of remote sensing data in water resource management around the world. In particular, it outlines the steps being undertaken by the Group on Earth Observations (GEO) and its Water Task to facilitate capacity building efforts in water management using Earth Observations in Asia, Africa and Latin and Caribbean America. Success stories on the benefits of using Earth Observations and applying GEO principles are provided. While GEO and its capacity building efforts are contributing to the transformation of water management through interoperability, data sharing, and capacity building, the full potential of these contributions has not been fully realized because impediments and challenges still remain.
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Earth as Building Material – an overview of RILEM activities and recent Innovations in Geotechnics
Directory of Open Access Journals (Sweden)
Vyncke Johan
2018-01-01
Full Text Available This paper presents an overview of the different earth building techniques, the latest innovations and the normative aspects. The oldest man made earth constructions known to exist date back to 10 000 BC. Since then, earth has remained a popular building material throughout history. With time, different techniques evolved, starting from sundried adobe blocks to cob constructions, rammed earth walls and compressed earth bricks. Today these techniques are still being optimized and alternative binders, specifically adapted admixtures and surface treatments are being developed. Even though nearly one third of the world’s population lives in an earth construction, few specific building standards and testing methods exist. Many of the tests used today are based on tests for concrete and thus do not take into account the complex nature of earth constructions, such as their sensitivity to water. RILEM, the union of Laboratories and Experts in Construction Materials, Systems and Structures, set up a new Technical Committee in 2016: TC TCE (Testing and Characterisation of Earth-based building materials and elements. This committee, consisting of an international group of experts on the topic, aim to define testing procedures for earth as a building construction material. To end with, this paper also gives a short introduction to “Deep soil mixing”, an “earth” building technique dedicated to geotechnical engineering.
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Capturing near-Earth asteroids around Earth
Hasnain, Zaki; Lamb, Christopher A.; Ross, Shane D.
2012-12-01
The list of detected near-Earth asteroids (NEAs) is constantly growing. NEAs are likely targets for resources to support space industrialization, as they may be the least expensive source of certain needed raw materials. The limited supply of precious metals and semiconducting elements on Earth may be supplemented or even replaced by the reserves floating in the form of asteroids around the solar system. Precious metals make up a significant fraction NEAs by mass, and even one metallic asteroid of ˜1km size and fair enrichment in platinum-group metals would contain twice the tonnage of such metals already harvested on Earth. There are ˜1000 NEAs with a diameter of greater than 1 km. Capturing these asteroids around the Earth would expand the mining industry into an entirely new dimension. Having such resources within easy reach in Earth's orbit could provide an off-world environmentally friendly remedy for impending terrestrial shortages, especially given the need for raw materials in developing nations. In this paper, we develop and implement a conceptually simple algorithm to determine trajectory characteristics necessary to move NEAs into capture orbits around the Earth. Altered trajectories of asteroids are calculated using an ephemeris model. Only asteroids of eccentricity less than 0.1 have been studied and the model is restricted to the ecliptic plane for simplicity. We constrain the time of retrieval to be 10 years or less, based on considerations of the time to return on investment. For the heliocentric phase, constant acceleration is assumed. The acceleration required for transporting these asteroids from their undisturbed orbits to the sphere of influence of the Earth is the primary output, along with the impulse or acceleration necessary to effect capture to a bound orbit once the Earth's sphere of influence is reached. The initial guess for the constant acceleration is provided by a new estimation method, similar in spirit to Edelbaum's. Based on the
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Seismic resistant design of a nuclear category I earth dam
International Nuclear Information System (INIS)
Vaidya, N.R.; Ries, E.R.; Kissenpfennig, J.F.
1975-01-01
An integral part of many nuclear power plants is the ultimate heat sink (UHS); the purpose of which is to retain and deliver a supply of service water to the plant when water from the primary circulating water system is not available. The earth dam described herein is designed to retain the reservoir for the UHS of a nuclear power plant in Southern Europe. The usual pseudo-static analysis is only as good as the estimate for the seismic coefficient used to compute an equivalent horizontal static force on a potential sliding mass. In view of the earth dam considered herein, a more accurate computation of the seismic coefficients is to be made. A two-dimensional dynamic finite element analysis is made to predict the response of the earth dam to a Safe Shutdown Earthquake excitation which is in the form of a time history of accelerations appropriately deconvoluted from the surficial time history and applied at the base of the model. The material properties such as shear modulus and damping are adjusted to be compatible with the level of strain obtained. Thus, non-linear behavior of soil is considered in the analysis and a more realistic response is predicted. Acceleration and stress are determined throughout the dam and are used to compute a seismic coefficient for a pseudo-static stability analysis and the dynamic strength to stress ratios at several points in the body of the dam. The need to design the dam to resist a progressive erosion accident resulting from postulated concentrated leaks is discussed. This may be accomplished by providing a wide, well graded core protected by wide transition cores also heavily compacted
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Optimal Safety Earthing – Earth Electrode Sizing Using A ...
African Journals Online (AJOL)
In this paper a deterministic approach in the sizing of earth electrode using the permissible touch voltage criteria is presented. The deterministic approach is effectively applied in the sizing of the length of earth rod required for the safe earthing of residential and facility buildings. This approach ensures that the earthing ...
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Bennett, V. C.; Nutman, A. P.
2017-12-01
Some of the strongest direct evidence that documents fundamental changes in the chemistry and organisation of Earth's interior derives from radiogenic isotopic compositions that include both long-lived (particularly 176Lu-176Hf and 147Sm-143Nd) and short-lived, i.e., now extinct parent isotope, systems (182Hf-182W, 146Sm-142Nd). Changes in patterns of isotopic evolution are linked to changes in mantle dynamics such that tracking these signatures in geologically well-characterised rocks can be used to discover the the nature and evolution of tectonic processes. Over the past decade, intensive geochemical investigations by various groups focussing on the oldest (> 4.0 Ga to 3.6 Ga) rock record, as preserved in several localities, have revealed isotopic distinctions in the early Earth compared with those in Proterozoic and younger rocks. For example, whilst the major and trace element compositions of Eoarchean gneisses have analogs in younger rocks in accord with a continuum of crust formation processes, radiogenic isotopic signatures from both long and short half-life decay schemes record an image of the Earth in transition from early differentiation processes, likely associated with planetary accretion and formation, to more modern style characterised by plate tectonics. The emerging image is that many Eoarchean rocks possess extinct nuclide anomalies in the form of 142Nd and 182Hf isotopic signatures that are absent in modern terrestrial samples; these signatures are evidence of chemical fractionation processes occuring within the first ca. 10-300 million years of Solar System history. In addition, viewing the global database, patterns of long-half life isotope signatures i.e., 143Nd and 176Hf differ from those seen in younger (modern Earth.
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Social and Environmental Impact of the Rare Earth Industries
Directory of Open Access Journals (Sweden)
Saleem H. Ali
2014-02-01
Full Text Available The use of rare earth elements in various technologies continues to grow despite some alternatives being found for particular uses. Given a history of ecological concerns about pollution from rare earth mines, particularly in China, there are growing social and environmental concerns about the growth of the mining and mineral processing in this sector. This is best exemplified by the recent social and environmental conflict surrounding the development of the Lynas Advanced Materials Plant (LAMP in Kuantan, Malaysia which led to international activism and claims of environmental and social injustice. This paper analyses the structure of environmental and social conflicts surrounding rare earth minerals and opportunities for improving the social and environmental performance of the sector. Many of these elements are used for green technologies. Opportunities exist that offer a more circular supply chain following industrial ecological principles through which reuse and recycling of the materials can provide a means of mitigating social and environmental conflicts in this sector. In addition, public engagement processes that recognize community concerns about radiation, and transparent scientifically predicated decision-making through an appropriate governance structure within regulatory organizations are also presented.
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Green, Rebecca
2017-01-01
Solid rockets are of interest to the space program because they are commonly used as boosters that provide the additional thrust needed for the space launch vehicle to escape the gravitational pull of the Earth. Larger, more advanced solid rockets allow for space launch vehicles with larger payload capacities, enabling mankind to reach new depths of space. This presentation will discuss, in detail, the history of solid rockets. The history begins with the invention and origin of the solid rocket, and then goes into the early uses and design of the solid rocket. The evolution of solid rockets is depicted by a description of how solid rockets changed and improved and how they were used throughout the 16th, 17th, 18th, and 19th centuries. Modern uses of the solid rocket include the Solid Rocket Boosters (SRBs) on the Space Shuttle and the solid rockets used on current space launch vehicles. The functions and design of the SRB and the advancements in solid rocket technology since the use of the SRB are discussed as well. Common failure modes and design difficulties are discussed as well.
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Modeling Earth Albedo for Satellites in Earth Orbit
DEFF Research Database (Denmark)
Bhanderi, Dan; Bak, Thomas
2005-01-01
Many satellite are influences by the Earthøs albedo, though very few model schemes exist.in order to predict this phenomenon. Earth albedo is often treated as noise, or ignored completely. When applying solar cells in the attitude hardware, Earth albedo can cause the attitude estimate to deviate...... with as much as 20 deg. Digital Sun sensors with Earth albedo correction in hardware exist, but are expensive. In addition, albedo estimates are necessary in thermal calculations and power budgets. We present a modeling scheme base4d on Eartht reflectance, measured by NASA's Total Ozone Mapping Spectrometer......, in which the Earth Probe Satellite has recorded reflectivity data daily since mid 1996. The mean of these data can be used to calculate the Earth albedo given the positions of the satellite and the Sun. Our results show that the albedo varies highly with the solar angle to the satellite's field of view...
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Kohler, Susanna
2016-06-01
How can we hunt down all the near-Earth asteroids that are capable of posing a threat to us? A new study looks at whether the upcoming Large Synoptic Survey Telescope (LSST) is up to the job.Charting Nearby ThreatsLSST is an 8.4-m wide-survey telescope currently being built in Chile. When it goes online in 2022, it will spend the next ten years surveying our sky, mapping tens of billions of stars and galaxies, searching for signatures of dark energy and dark matter, and hunting for transient optical events like novae and supernovae. But in its scanning, LSST will also be looking for asteroids that approach near Earth.Cumulative number of near-Earth asteroids discovered over time, as of June 16, 2016. [NASA/JPL/Chamberlin]Near-Earth objects (NEOs) have the potential to be hazardous if they cross Earths path and are large enough to do significant damage when they impact Earth. Earths history is riddled with dangerous asteroid encounters, including the recent Chelyabinsk airburst in 2013, the encounter that caused the kilometer-sized Meteor Crater in Arizona, and the impact thought to contribute to the extinction of the dinosaurs.Recognizing the potential danger that NEOs can pose to Earth, Congress has tasked NASA with tracking down 90% of NEOs larger than 140 meters in diameter. With our current survey capabilities, we believe weve discovered roughly 25% of these NEOs thus far. Now a new study led by Tommy Grav (Planetary Science Institute) examines whether LSST will be able to complete this task.Absolute magnitude, H, of asynthetic NEO population. Though these NEOs are all larger than 140 m, they have a large spread in albedos. [Grav et al. 2016]Can LSST Help?Based on previous observations of NEOs and resulting predictions for NEO properties and orbits, Grav and collaborators simulate a synthetic population of NEOs all above 140 m in size. With these improved population models, they demonstrate that the common tactic of using an asteroids absolute magnitude as a
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Nam, Younkyeong; Karahan, Engin; Roehrig, Gillian
2016-01-01
Geologic time scale is a very important concept for understanding long-term earth system events such as climate change. This study examines forty-three 4th-8th grade Native American--particularly Ojibwe tribe--students' understanding of relative ordering and absolute time of Earth's significant geological and biological events. This study also…
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Earth as an extrasolar planet: Earth model validation using EPOXI earth observations.
Robinson, Tyler D; Meadows, Victoria S; Crisp, David; Deming, Drake; A'hearn, Michael F; Charbonneau, David; Livengood, Timothy A; Seager, Sara; Barry, Richard K; Hearty, Thomas; Hewagama, Tilak; Lisse, Carey M; McFadden, Lucy A; Wellnitz, Dennis D
2011-06-01
The EPOXI Discovery Mission of Opportunity reused the Deep Impact flyby spacecraft to obtain spatially and temporally resolved visible photometric and moderate resolution near-infrared (NIR) spectroscopic observations of Earth. These remote observations provide a rigorous validation of whole-disk Earth model simulations used to better understand remotely detectable extrasolar planet characteristics. We have used these data to upgrade, correct, and validate the NASA Astrobiology Institute's Virtual Planetary Laboratory three-dimensional line-by-line, multiple-scattering spectral Earth model. This comprehensive model now includes specular reflectance from the ocean and explicitly includes atmospheric effects such as Rayleigh scattering, gas absorption, and temperature structure. We have used this model to generate spatially and temporally resolved synthetic spectra and images of Earth for the dates of EPOXI observation. Model parameters were varied to yield an optimum fit to the data. We found that a minimum spatial resolution of ∼100 pixels on the visible disk, and four categories of water clouds, which were defined by using observed cloud positions and optical thicknesses, were needed to yield acceptable fits. The validated model provides a simultaneous fit to Earth's lightcurve, absolute brightness, and spectral data, with a root-mean-square (RMS) error of typically less than 3% for the multiwavelength lightcurves and residuals of ∼10% for the absolute brightness throughout the visible and NIR spectral range. We have extended our validation into the mid-infrared by comparing the model to high spectral resolution observations of Earth from the Atmospheric Infrared Sounder, obtaining a fit with residuals of ∼7% and brightness temperature errors of less than 1 K in the atmospheric window. For the purpose of understanding the observable characteristics of the distant Earth at arbitrary viewing geometry and observing cadence, our validated forward model can be
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Water in the Earth's Interior: Distribution and Origin
Peslier, Anne H.; Schönbächler, Maria; Busemann, Henner; Karato, Shun-Ichiro
2017-10-01
The concentration and distribution of water in the Earth has influenced its evolution throughout its history. Even at the trace levels contained in the planet's deep interior (mantle and core), water affects Earth's thermal, deformational, melting, electrical and seismic properties, that control differentiation, plate tectonics and volcanism. These in turn influenced the development of Earth's atmosphere, oceans, and life. In addition to the ubiquitous presence of water in the hydrosphere, most of Earth's "water" actually occurs as trace amounts of hydrogen incorporated in the rock-forming silicate minerals that constitute the planet's crust and mantle, and may also be stored in the metallic core. The heterogeneous distribution of water in the Earth is the result of early planetary differentiation into crust, mantle and core, followed by remixing of lithosphere into the mantle after plate-tectonics started. The Earth's total water content is estimated at 18_{-15}^{+81} times the equivalent mass of the oceans (or a concentration of 3900_{-3300}^{+32700} ppm weight H2O). Uncertainties in this estimate arise primarily from the less-well-known concentrations for the lower mantle and core, since samples for water analyses are only available from the crust, the upper mantle and very rarely from the mantle transition zone (410-670 km depth). For the lower mantle (670-2900 km) and core (2900-4500 km), the estimates rely on laboratory experiments and indirect geophysical techniques (electrical conductivity and seismology). The Earth's accretion likely started relatively dry because it mainly acquired material from the inner part of the proto-planetary disk, where temperatures were too high for the formation and accretion of water ice. Combined evidence from several radionuclide systems (Pd-Ag, Mn-Cr, Rb-Sr, U-Pb) suggests that water was not incorporated in the Earth in significant quantities until the planet had grown to ˜60-90% of its current size, while core formation
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Digital Earth - A sustainable Earth
Mahavir
2014-02-01
All life, particularly human, cannot be sustainable, unless complimented with shelter, poverty reduction, provision of basic infrastructure and services, equal opportunities and social justice. Yet, in the context of cities, it is believed that they can accommodate more and more people, endlessly, regardless to their carrying capacity and increasing ecological footprint. The 'inclusion', for bringing more and more people in the purview of development is often limited to social and economic inclusion rather than spatial and ecological inclusion. Economic investment decisions are also not always supported with spatial planning decisions. Most planning for a sustainable Earth, be at a level of rural settlement, city, region, national or Global, fail on the capacity and capability fronts. In India, for example, out of some 8,000 towns and cities, Master Plans exist for only about 1,800. A chapter on sustainability or environment is neither statutorily compulsory nor a norm for these Master Plans. Geospatial technologies including Remote Sensing, GIS, Indian National Spatial Data Infrastructure (NSDI), Indian National Urban Information Systems (NUIS), Indian Environmental Information System (ENVIS), and Indian National GIS (NGIS), etc. have potential to map, analyse, visualize and take sustainable developmental decisions based on participatory social, economic and social inclusion. Sustainable Earth, at all scales, is a logical and natural outcome of a digitally mapped, conceived and planned Earth. Digital Earth, in fact, itself offers a platform to dovetail the ecological, social and economic considerations in transforming it into a sustainable Earth.
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Earthlike planets: Surfaces of Mercury, Venus, earth, moon, Mars
Murray, B.; Malin, M. C.; Greeley, R.
1981-01-01
The surfaces of the earth and the other terrestrial planets of the inner solar system are reviewed in light of the results of recent planetary explorations. Past and current views of the origin of the earth, moon, Mercury, Venus and Mars are discussed, and the surface features characteristic of the moon, Mercury, Mars and Venus are outlined. Mechanisms for the modification of planetary surfaces by external factors and from within the planet are examined, including surface cycles, meteoritic impact, gravity, wind, plate tectonics, volcanism and crustal deformation. The origin and evolution of the moon are discussed on the basis of the Apollo results, and current knowledge of Mercury and Mars is examined in detail. Finally, the middle periods in the history of the terrestrial planets are compared, and future prospects for the exploration of the inner planets as well as other rocky bodies in the solar system are discussed.
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The physics and history of global warming
International Nuclear Information System (INIS)
Hu Yongyun
2012-01-01
Global warming is not only a hot research area in atmospheric sciences and even all Earth sciences but is also a controversial topic in the international community. The purpose of this paper is not to clarify these controversies, but instead, to address the physical basis on which our understanding of global warming is founded, and to briefly review the nearly 200-year history of global warming sciences. We hope the paper will help readers, who have no background in the atmospheric and climate sciences, understand scientific issues of global warming. (author)
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Simulating the Thermal History of the Unsaturated Zone at Yucca Mountain, Nevada
International Nuclear Information System (INIS)
B.D. Marshal; J.F. Whelan
2001-01-01
Heat transfer within Earth's upper crust is primarily by conduction, and conductive thermal models adequately explain the cooling history of deep, batholith-scale intrusions and surrounding wall rocks, as confirmed by numerous thermochronometric studies. However, caldera magmatic systems require consideration of the small and localized component of hydrothermal convection and numerical models to simulate additional boundary conditions, irregular magma chamber shapes, and complex intrusive histories. At Yucca Mountain, Nevada, the site of a potential high-level nuclear waste repository, simulating the detailed thermal history at any location in the unsaturated zone requires knowledge of the shape of the magma chamber and its proximity to Yucca Mountain (the southern margin of the Timber Mountain caldera complex is approximately 8 km north of the potential repository site), the temporal and spatial extent of hydrothermal convection, the erosional history of the area, and past levels of the water table
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Low-energy near Earth asteroid capture using Earth flybys and aerobraking
Tan, Minghu; McInnes, Colin; Ceriotti, Matteo
2018-04-01
Since the Sun-Earth libration points L1 and L2 are regarded as ideal locations for space science missions and candidate gateways for future crewed interplanetary missions, capturing near-Earth asteroids (NEAs) around the Sun-Earth L1/L2 points has generated significant interest. Therefore, this paper proposes the concept of coupling together a flyby of the Earth and then capturing small NEAs onto Sun-Earth L1/L2 periodic orbits. In this capture strategy, the Sun-Earth circular restricted three-body problem (CRTBP) is used to calculate target Lypaunov orbits and their invariant manifolds. A periapsis map is then employed to determine the required perigee of the Earth flyby. Moreover, depending on the perigee distance of the flyby, Earth flybys with and without aerobraking are investigated to design a transfer trajectory capturing a small NEA from its initial orbit to the stable manifolds associated with Sun-Earth L1/L2 periodic orbits. Finally, a global optimization is carried out, based on a detailed design procedure for NEA capture using an Earth flyby. Results show that the NEA capture strategies using an Earth flyby with and without aerobraking both have the potential to be of lower cost in terms of energy requirements than a direct NEA capture strategy without the Earth flyby. Moreover, NEA capture with an Earth flyby also has the potential for a shorter flight time compared to the NEA capture strategy without the Earth flyby.
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Mass Redistribution in the Core and Time-varying Gravity at the Earth's Surface
Kuang, Wei-Jia; Chao, Benjamin F.; Fang, Ming
2003-01-01
The Earth's liquid outer core is in convection, as suggested by the existence of the geomagnetic field in much of the Earth's history. One consequence of the convection is the redistribution of mass resulting from relative motion among fluid parcels with slightly different densities. This time dependent mass redistribution inside the core produces a small perturbation on the gravity field of the Earth. With our numerical dynamo solutions, we find that the mass redistribution (and the resultant gravity field) symmetric about the equator is much stronger than that anti-symmetric about the equator. In particular, J(sub 2) component is the strongest. In addition, the gravity field variation increases with the Rayleigh number that measures the driving force for the geodynamo in the core. With reasonable scaling from the current dynamo solutions, we could expect that at the surface of the Earth, the J(sub 2) variation from the core is on the order of l0(exp -16)/year relative to the mean (i.e. spherically symmetric) gravity field of the Earth. The possible shielding effect due to core-mantle boundary pressure variation loading is likely much smaller and is therefore negligible. Our results suggest that time-varying gravity field perturbation due to core mass redistribution may be measured with modem space geodetic observations, which will result a new means of detecting dynamical processes in the Earth's deep interior.
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Continuity of Earth Radiation Budget Observations
Loeb, N. G.; Su, W.; Wong, T.; Priestley, K.
2017-12-01
Earth's climate is determined by the exchange of radiant energy between the Sun, Earth and space. The absorbed solar radiation at the top-of-atmosphere (TOA) fuels the climate system, providing the energy required for atmospheric and oceanic motions. Earth's radiation budget (ERB) involves a balance between how much solar energy Earth absorbs and how much terrestrial thermal infrared radiation is emitted to space. Because of its critical role in climate, continuous monitoring of the ERB is necessary for improved understanding and prediction of climate variability and change. NASA's long history in observing the TOA ERB is acknowledged in the 2007 and 2013 reports of the IPCC (IPCC 2007, 2013), the 2007 NRC Decadal Survey (NRC 2007), and the GCOS implementation plan of the WMO (GCOS 2016). A key reason for NASA's success in this area is due to its support of the CERES Project and its predecessor, ERBE. During ERBE, the TOA ERB was observed using both scanner and nonscanner broadband instruments. The CERES project consists of six scanner instruments flying alongside high-resolution spectral imagers (MODIS, VIIRS) in morning and afternoon sun-synchronous orbits. In addition to extending the ERBE TOA radiation budget record, CERES also provides observations of Earth's surface radiation budget with unprecedented accuracy. Here we assess the likelihood of a measurement gap in the ERB record. We show that unless a follow-on ERB instrument to the last available CERES copy (FM6) is built and launched, there is a significant risk of a measurement gap in the ERB record by the mid-2020s. A gap is of concern not only because the ERB would not be monitored during the gap period but also because it would be exceedingly difficult to tie the records before and after the gap together with sufficient accuracy for climate analyses. While ERB instruments are highly stable temporally, they lack the absolute accuracy needed to bridge a gap. Consequently, there is a requirement that
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Glances on uranium. From uranium in the earth to electric power
International Nuclear Information System (INIS)
Valsardieu, C.
1995-01-01
This book is a technical, scientific and historical analysis of the nuclear fuel cycle from the origin of uranium in the earth and the exploitation of uranium ores to the ultimate storage of radioactive wastes. It comprises 6 chapters dealing with: 1) the different steps of uranium history (discovery, history of uranium chemistry, the radium era, the physicists and the structure of matter, the military uses, the nuclear power, the uranium industry and economics), 2) the uranium in nature (nuclear structure, physical-chemical properties, radioactivity, ores, resources, cycle, deposits), 3) the sidelights on uranium history (mining, prospecting, experience, ore processing, resources, reserves, costs), 4) the uranium in the fuel cycle, energy source and industrial product (fuel cycle, fission, refining, enrichment, fuel processing and reprocessing, nuclear reactors, wastes management), 5) the other energies in competition and the uranium market (other uranium uses, fossil fuels and renewable energies, uranium market), and 6) the future of uranium (forecasting, ecology, economics). (J.S.)
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Energy Technology Data Exchange (ETDEWEB)
Cranstone, D A
1979-01-01
Rare earth elements are commonly extracted from the minerals monazite, bastnaesite, and xenotine. New uses for these elements are constantly developing; they have found applications in glass polishing, television tube phosphors, high-strength low-alloy steels, magnets, catalysts, refractory ceramics, and hydrogen sponge alloys. In Canada, rare earths have been produced as byproducts of the uranium mining industry, but there was no production of rare earths in 1978 or 1979. The world sources of and markets for the rare earth elements are discussed.
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Stasis and convergence characterize morphological evolution in eupolypod II ferns.
Sundue, Michael A; Rothfels, Carl J
2014-01-01
Patterns of morphological evolution at levels above family rank remain underexplored in the ferns. The present study seeks to address this gap through analysis of 79 morphological characters for 81 taxa, including representatives of all ten families of eupolypod II ferns. Recent molecular phylogenetic studies demonstrate that the evolution of the large eupolypod II clade (which includes nearly one-third of extant fern species) features unexpected patterns. The traditional 'athyrioid' ferns are scattered across the phylogeny despite their apparent morphological cohesiveness, and mixed among these seemingly conservative taxa are morphologically dissimilar groups that lack any obvious features uniting them with their relatives. Maximum-likelihood and maximum-parsimony character optimizations are used to determine characters that unite the seemingly disparate groups, and to test whether the polyphyly of the traditional athyrioid ferns is due to evolutionary stasis (symplesiomorphy) or convergent evolution. The major events in eupolypod II character evolution are reviewed, and character and character state concepts are reappraised, as a basis for further inquiries into fern morphology. Characters were scored from the literature, live plants and herbarium specimens, and optimized using maximum-parsimony and maximum-likelihood, onto a highly supported topology derived from maximum-likelihood and Bayesian analysis of molecular data. Phylogenetic signal of characters were tested for using randomization methods and fitdiscrete. The majority of character state changes within the eupolypod II phylogeny occur at the family level or above. Relative branch lengths for the morphological data resemble those from molecular data and fit an ancient rapid radiation model (long branches subtended by very short backbone internodes), with few characters uniting the morphologically disparate clades. The traditional athyrioid ferns were circumscribed based upon a combination of
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195-Year History of Mykolayiv Observatory: Events and People
Directory of Open Access Journals (Sweden)
Shulga, O.V.
2017-01-01
Full Text Available The basic stages of the history of the Mykolaiv Astronomical Observatory are shown. The main results of the Observatory activities are presented by the catalogs of star positions, major and minor planets in the Solar system, space objects in the Earth orbit. The information on the qualitative and quantitative structure of the Observatory, cooperation with the observatories of Ukraine and foreign countries as well as major projects carried out in the Observatory is provided.
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ISS EarthKam: Taking Photos of the Earth from Space
Haste, Turtle
2008-01-01
NASA is involved in a project involving the International Space Station (ISS) and an Earth-focused camera called EarthKam, where schools, and ultimately students, are allowed to remotely program the EarthKAM to take images. Here the author describes how EarthKam was used to help middle school students learn about biomes and develop their…
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Role of light satellites in the high-resolution Earth observation domain
Fishman, Moshe
1999-12-01
Current 'classic' applications using and exploring space based earth imagery are exclusive, narrow niche tailored, expensive and hardly accessible. On the other side new, inexpensive and widely used 'consumable' applications will be only developed concurrently to the availability of appropriate imagery allowing that process. A part of these applications can be imagined today, like WWW based 'virtual tourism' or news media, but the history of technological, cultural and entertainment evolution teaches us that most of future applications are unpredictable -- they emerge together with the platforms enabling their appearance. The only thing, which can be ultimately stated, is that the definitive condition for such applications is the availability of the proper imagery platform providing low cost, high resolution, large area, quick response, simple accessibility and quick dissemination of the raw picture. This platform is a constellation of Earth Observation satellites. Up to 1995 the Space Based High Resolution Earth Observation Domain was dominated by heavy, super-expensive and very inflexible birds. The launch of Israeli OFEQ-3 Satellite by MBT Division of Israel Aircraft Industries (IAI) marked the entrance to new era of light, smart and cheap Low Earth Orbited Imaging satellites. The Earth Resource Observation System (EROS) initiated by West Indian Space, is based on OFEQ class Satellites design and it is capable to gather visual data of Earth Surface both at high resolution and large image capacity. The main attributes, derived from its compact design, low weight and sophisticated logic and which convert the EROS Satellite to valuable and productive system, are discussed. The major advantages of Light Satellites in High Resolution Earth Observation Domain are presented and WIS guidelines featuring the next generation of LEO Imaging Systems are included.
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Rare gas systematics: Formation of the atmosphere, evolution and structure of the Earth's mantle
International Nuclear Information System (INIS)
Allegre, C.J.; Staudacher, T.; Sarda, P.; Paris-6 Univ., 75; Paris-7 Univ., 75
1987-01-01
To explain the rare gas content and isotopic composition measured in modern terrestrial materials we explore in this paper an Earth model based on four reservoirs: atmosphere, continental crust, upper mantle and lower mantle. This exploration employs three tools: mass balance equations, the concept of mean age of outgassing and the systematic use of all of the rare gases involving both absolute amount and isotopic composition. The results obtained are as follows: half of the Earth's mantle is 99% outgassed. Outgassing occurred in an early very intense stage within the first 50 Ma of Earth history and a slow continuous stage which continues to the present day. The mean age of the atmosphere is 4.4 Ga. Our model with four main reservoirs explains quantitatively both isotopic and chemical ratios, assuming that He migrates from the lower to the upper mantle whereas the heavy rare gases did not. Noble gas fluxes for He, Ar and Xe from different reservoirs have been estimated. The results constrain the K content in the earth to 278 ppm. Several geodynamic consequences are discussed. (orig.)
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Attraction of the opposites: reception of the Theory of Evolution in Young Earth creationists
Directory of Open Access Journals (Sweden)
Alexander Khramov
2018-12-01
Full Text Available The history of the Young Earth creationism can be divided into two stages, namely the period of Scriptural geology, which lasted from the 1820s to the 1860s mostly in Britain, and the modern period, which began in the USA in the 1920s and continued into the 21st century. During both these periods, some Young-Earth creationists made attempts to employ the notions of evolution in order to bolster a highly literalistic interpretation of the biblical narrative about the Creation and the Flood. In their opinion, the hypothesis of ultra-rapid evolution off ered a plausible explanation of how a small number of species which were in Noah’s Ark could have produced the very diverse modern fauna of terrestrial organisms without supernatural interventions on the part of God. The fact that the elements of the theory of evolution were accepted by some prominent Young Earth creationists demonstrates that it would be an exaggeration to ascribe uncompromised hostility towards the idea of evolution to the Young Earth movement as a whole.
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International Nuclear Information System (INIS)
Bondar', I.A.; Vinogradova, N.V.; Dem'yanets, L.N.
1983-01-01
Rare earth germanates attract close attention both as an independent class of compounds and analogues of a widely spread class of natural and synthetic minerals. The methods of rare earth germanate synthesis (solid-phase, hydrothermal) are considered. Systems on the basis of germanium and rare earth oxides, phase diagrams, phase transformations are studied. Using different chemical analysese the processes of rare earth germanate formation are investigated. IR spectra of alkali and rare earth metal germanates are presented, their comparative analysis being carried out. Crystal structures of the compounds, lattice parameters are studied. Fields of possible application of rare earth germanates are shown
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International Nuclear Information System (INIS)
Komissarova, L.N.; Shatskij, V.M.; Pokrovskij, A.N.; Chizhov, S.M.; Bal'kina, T.I.; Suponitskij, Yu.L.
1986-01-01
Results of experimental works on the study of synthesis conditions, structure and physico-chemical properties of rare earth, scandium and yttrium sulfates, have been generalized. Phase diagrams of solubility and fusibility, thermodynamic and crystallochemical characteristics, thermal stability of hydrates and anhydrous sulfates of rare earths, including normal, double (with cations of alkali and alkaline-earth metals), ternary and anion-mixed sulfates of rare earths, as well as their adducts, are considered. The state of ions of rare earths, scandium and yttrium in aqueous sulfuric acid solutions is discussed. Data on the use of rare earth sulfates are given
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Grcevich, Jana; Pagnotta, Ashley; Mac Low, Mordecai-Mark; Shara, Michael; Flores, Kennet; Nadeau, Patricia A.; Sessa, Jocelyn; Ustunisik, Gokce; Zirakparvar, Nasser; Ebel, Denton; Harlow, George; Webster, James D.; Kinzler, Rosamond; MacDonald, Maritza B.; Contino, Julie; Cooke-Nieves, Natasha; Howes, Elaine; Zachowski, Marion
2015-01-01
The Master of Arts in Teaching (MAT) Program at the American Museum of Natural History is a innovative program designed to prepare participants to be world-class Earth Science teachers. New York State is experiencing a lack of qualified Earth Science teachers, leading in the short term to a reduction in students who successfully complete the Earth Science Regents examination, and in the long term potential reductions in the number of students who go on to pursue college degrees in Earth Science related disciplines. The MAT program addresses this problem via a collaboration between practicing research scientists and education faculty. The faculty consists of curators and postdoctoral researchers from the Departments of Astrophysics, Earth and Planetary Sciences, and the Division of Paleontology, as well as doctoral-level education experts. During the 15-month, full-time program, students participate in a residency program at local urban classrooms as well as taking courses and completing field work in astrophysics, geology, earth science, and paleontology. The program targets high-needs schools with diverse populations. We seek to encourage, stimulate interest, and inform the students impacted by our program, most of whom are from traditionally underrepresented backgrounds, about the rich possibilities for careers in Earth Science related disciplines and the intrinsic value of the subject. We report on the experience of the first and second cohorts, all of whom are now employed in full time teaching positions, and the majority in high needs schools in New York State.
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The most important message in the history of mankind
Directory of Open Access Journals (Sweden)
Skubała Piotr
2016-06-01
Full Text Available It the long history of life on the Earth five major mass extinctions were observed. Nowadays, the impact of human activities on the planet has accelerated the loss of species and ecosystems to a level comparable to a sixth mass extinction, the first driven by a living species. Surprisingly, this fact rarely reaches the public consciousness. The negative influence of human activity is observed in whole area of land ecosystems, whereas marine ecosystems are at risk of entering a phase of extinction unprecedented in human history. We have domesticated landscapes and ecosystems causing unforeseen changes in ecosystem attributes. Humanity has already overshot global biocapacity by 50% and now lives unsustainabily by depleting stocks of natural capital. Three the Earth-system processes - climate change, rate of biodiversity loss and interference with the nitrogen cycle - have already transgressed their boundaries. Human activities are of sufficient magnitude to suggest that we have triggered a new geological epoch, the Anthropocene. The “Biosphere 2” project revailed that we are not able to build and control a different system life and that we are totally dependent on the present biosphere. The experiment known in the literature as “The Tragedy of the Commons” reminds us that we need frugality and cooperation to solve environmental problems and survive.
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Mote, A. S.; Lockwood, J.; Ellins, K. K.; Haddad, N.; Ledley, T. S.; Lynds, S. E.; McNeal, K.; Libarkin, J. C.
2014-12-01
EarthLabs, an exemplary series of lab-based climate science learning modules, is a model for high school Earth Science lab courses. Each module includes a variety of learning activities that allow students to explore the Earth's complex and dynamic climate history. The most recent module, Climate Detectives, uses data from IODP Expedition 341, which traveled to the Gulf of Alaska during the summer of 2013 to study past climate, sedimentation, and tectonics along the continental margin. At the onset of Climate Detectives, students are presented with a challenge engaging them to investigate how the Earth's climate has changed since the Miocene in southern Alaska. To complete this challenge, students join Exp. 341 to collect and examine sediments collected from beneath the seafloor. The two-week module consists of six labs that provide students with the content and skills needed to solve this climate mystery. Students discover how an international team collaborates to examine a scientific problem with the IODP, compete in an engineering design challenge to learn about scientific ocean drilling, and learn about how different types of proxy data are used to detect changes in Earth's climate. The NGSS Science and Engineering Practices are woven into the culminating activity, giving students the opportunity to think and act like scientists as they investigate the following questions: 1) How have environmental conditions in in the Gulf of Alaska changed during the time when the sediments in core U1417 were deposited? (2) What does the occurrence of different types of diatoms and their abundance reveal about the timing of the cycles of glacial advance and retreat? (3) What timeline is represented by the section of core? (4) How do results from the Gulf of Alaska compare with the global record of glaciations during this period based on oxygen isotopes proxies? Developed by educators in collaboration with Expedition 341 scientists, Climate Detectives is a strong example of
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Spohn, Tilman
2013-04-01
Convection in the interiors of planetesimals (asteroids), planets, and satellites is driving the thermal and chemical evolution of these bodies including the generation of possible magnetic fields. The wide size range induces a wide of range of time scales from hundreds of thousands of years for small planetesimals to a few tens of Gigayears for massive super-Earths. Evolution calculations are often based on energy (and entropy) balances parameterizing the transport properties of the interior in suitable ways. These thereby allow incorporating (in parameterized forms) interesting physical processes that depend in one way or another on the transport properties of the interior. The interior will usually be chemically layered in mantles and cores and include ice layers if icy satellites are considered. In addition to magnetic field generation calculated via energy balances of the core and using semi-empirical dynamo strength relations, processes that can be considered include sintering and compaction for small bodies and mantle (or ice) melting, differentiation and even continental growth for full-scaled terrestrial planets. The rheology of the interior is considered temperature and pressure dependent and the concentration of volatiles can be important. For super-Earths, probably the most critical consideration is how the mantle rheology would vary with pressure and thus with depth. It is possible that the increasing pressure will frustrate deep mantle convection thereby reducing the vigor of mantle convection. Possibly, the generation of a magnetic field in a putative iron-rich core will be impossible, if super-Earths at all have earth-like cores. On a much smaller scale, the decay of short-lived radioactives suffices to heat and melt planetesimals, the melting being helped by the low thermal conductivity of the initially porous body. This allows planets to form from pre-differentiated planetesimals thus helping to differentiate and form cores rapidly. On active
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Ribas, Núria; Màrquez, Conxita
2013-04-01
text: We describe a didactic unit that rises from our own living impression about our experience on the planet. Most of us feel the Earth to be a very static place. Rocks don't easily move and most landscapes always look the same over time. Anyone would say (the same way most scientists believed until the beginning of the last century) that our planet has always remained unchanged, never transformed. But then, all of a sudden, as a misfortune for so many humans, natural hazards appear on the scene: an earthquake causing so many disasters, a tsunami carrying away everything in its path, an eruption that can destroy huge surrounding areas but also bring new geographical relief. Science cannot remain oblivious to these events, we must wonder beyond. What does an earthquake mean? Why does it happen? What about an eruption? If it comes from the inside, what can we guess from it? Researching about all of these events, scientists have been able to arrive to some important knowledge of the planet itself: It has been possible to theorize about Earth's interior. It has also been confirmed that the planet has not always been the quiet and stable place we once thought. Continents, as Wegener supposed, do move about and the Tectonic Plates Theory, thanks to the information obtained through earthquakes and eruption, can provide some interesting explanations. But how do we know about our planet's past? How can we prove that the Earth has always been moving and that its surface changes? The Earth's rocks yield the answer. Rocks have been the only witnesses throughout millions of years, since the planet first came to existence. Let's learn how to read them… Shouldn't we realize that rocks are to Geology what books are to History? This discursive process has been distributed in four learning sequences: 1. Land is not as solid nor firm as it would seem, 2. The Earth planet: a puzzle, 3. The rocks also recycle , 4. Field trip to "Sant Miquel del Fai". The subjects take about 30
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Digital Earth – A sustainable Earth
International Nuclear Information System (INIS)
Mahavir
2014-01-01
All life, particularly human, cannot be sustainable, unless complimented with shelter, poverty reduction, provision of basic infrastructure and services, equal opportunities and social justice. Yet, in the context of cities, it is believed that they can accommodate more and more people, endlessly, regardless to their carrying capacity and increasing ecological footprint. The 'inclusion', for bringing more and more people in the purview of development is often limited to social and economic inclusion rather than spatial and ecological inclusion. Economic investment decisions are also not always supported with spatial planning decisions. Most planning for a sustainable Earth, be at a level of rural settlement, city, region, national or Global, fail on the capacity and capability fronts. In India, for example, out of some 8,000 towns and cities, Master Plans exist for only about 1,800. A chapter on sustainability or environment is neither statutorily compulsory nor a norm for these Master Plans. Geospatial technologies including Remote Sensing, GIS, Indian National Spatial Data Infrastructure (NSDI), Indian National Urban Information Systems (NUIS), Indian Environmental Information System (ENVIS), and Indian National GIS (NGIS), etc. have potential to map, analyse, visualize and take sustainable developmental decisions based on participatory social, economic and social inclusion. Sustainable Earth, at all scales, is a logical and natural outcome of a digitally mapped, conceived and planned Earth. Digital Earth, in fact, itself offers a platform to dovetail the ecological, social and economic considerations in transforming it into a sustainable Earth
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Materials, matter and particles a brief history
Woolfson, Michael M
2010-01-01
This book traces the history of ideas about the nature of matter and also the way that mankind has used material resources that the world offers. Starting with the ideas of ancient civilizations that air, earth, fire and water were the basic ingredients of all matter, it traces the development of the science of chemistry beginning within the ranks of the alchemists. First, the idea of elements grew and then the atomic nature of matter was verified. Physicists had entered the scene, showing the nature of atoms in terms of fundamental particles and then introducing the concept of wave-particle d
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Smith, Michael J.
2004-01-01
This article briefly describes Earth science. The study of Earth science provides the foundation for an understanding of the Earth, its processes, its resources, and its environment. Earth science is the study of the planet in its entirety, how its lithosphere, atmosphere, hydrosphere, and biosphere work together as systems and how they affect…
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Stoever, Edward C., Jr.
Crustal Evolution Education Project (CEEP) modules were designed to: (1) provide students with the methods and results of continuing investigations into the composition, history, and processes of the earth's crust and the application of this knowledge to man's activities and (2) to be used by teachers with little or no previous background in the…
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Bohmian histories and decoherent histories
International Nuclear Information System (INIS)
Hartle, James B.
2004-01-01
The predictions of the Bohmian and the decoherent (or consistent) histories formulations of the quantum mechanics of a closed system are compared for histories--sequences of alternatives at a series of times. For certain kinds of histories, Bohmian mechanics and decoherent histories may both be formulated in the same mathematical framework within which they can be compared. In that framework, Bohmian mechanics and decoherent histories represent a given history by different operators. Their predictions for the probabilities of histories of a closed system therefore generally differ. However, in an idealized model of measurement, the predictions of Bohmian mechanics and decoherent histories coincide for the probabilities of records of measurement outcomes. The formulations are thus difficult to distinguish experimentally. They may differ in their accounts of the past history of the Universe in quantum cosmology
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Earth observation from the manned low Earth orbit platforms
Guo, Huadong; Dou, Changyong; Zhang, Xiaodong; Han, Chunming; Yue, Xijuan
2016-05-01
The manned low Earth orbit platforms (MLEOPs), e.g., the U.S. and Russia's human space vehicles, the International Space Station (ISS) and Chinese Tiangong-1 experimental space laboratory not only provide laboratories for scientific experiments in a wide range of disciplines, but also serve as exceptional platforms for remote observation of the Earth, astronomical objects and space environment. As the early orbiting platforms, the MLEOPs provide humans with revolutionary accessibility to the regions on Earth never seen before. Earth observation from MLEOPs began in early 1960s, as a part of manned space flight programs, and will continue with the ISS and upcoming Chinese Space Station. Through a series of flight missions, various and a large amount of Earth observing datasets have been acquired using handheld cameras by crewmembers as well as automated sophisticated sensors onboard these space vehicles. Utilizing these datasets many researches have been conducted, demonstrating the importance and uniqueness of studying Earth from a vantage point of MLEOPs. For example, the first, near-global scale digital elevation model (DEM) was developed from data obtained during the shuttle radar topography mission (SRTM). This review intends to provide an overview of Earth observations from MLEOPs and present applications conducted by the datasets collected by these missions. As the ISS is the most typical representative of MLEOPs, an introduction to it, including orbital characteristics, payload accommodations, and current and proposed sensors, is emphasized. The advantages and challenges of Earth observation from MLEOPs, using the ISS as an example, is also addressed. At last, a conclusive note is drawn.
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A super-Earth transiting a nearby low-mass star.
Charbonneau, David; Berta, Zachory K; Irwin, Jonathan; Burke, Christopher J; Nutzman, Philip; Buchhave, Lars A; Lovis, Christophe; Bonfils, Xavier; Latham, David W; Udry, Stéphane; Murray-Clay, Ruth A; Holman, Matthew J; Falco, Emilio E; Winn, Joshua N; Queloz, Didier; Pepe, Francesco; Mayor, Michel; Delfosse, Xavier; Forveille, Thierry
2009-12-17
A decade ago, the detection of the first transiting extrasolar planet provided a direct constraint on its composition and opened the door to spectroscopic investigations of extrasolar planetary atmospheres. Because such characterization studies are feasible only for transiting systems that are both nearby and for which the planet-to-star radius ratio is relatively large, nearby small stars have been surveyed intensively. Doppler studies and microlensing have uncovered a population of planets with minimum masses of 1.9-10 times the Earth's mass (M[symbol:see text]), called super-Earths. The first constraint on the bulk composition of this novel class of planets was afforded by CoRoT-7b (refs 8, 9), but the distance and size of its star preclude atmospheric studies in the foreseeable future. Here we report observations of the transiting planet GJ 1214b, which has a mass of 6.55M[symbol:see text]), and a radius 2.68 times Earth's radius (R[symbol:see text]), indicating that it is intermediate in stature between Earth and the ice giants of the Solar System. We find that the planetary mass and radius are consistent with a composition of primarily water enshrouded by a hydrogen-helium envelope that is only 0.05% of the mass of the planet. The atmosphere is probably escaping hydrodynamically, indicating that it has undergone significant evolution during its history. The star is small and only 13 parsecs away, so the planetary atmosphere is amenable to study with current observatories.
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Dickey, Jean O.
1995-01-01
The study of the Earth's rotation in space (encompassing Universal Time (UT1), length of day, polar motion, and the phenomena of precession and nutation) addresses the complex nature of Earth orientation changes, the mechanisms of excitation of these changes and their geophysical implications in a broad variety of areas. In the absence of internal sources of energy or interactions with astronomical objects, the Earth would move as a rigid body with its various parts (the crust, mantle, inner and outer cores, atmosphere and oceans) rotating together at a constant fixed rate. In reality, the world is considerably more complicated, as is schematically illustrated. The rotation rate of the Earth's crust is not constant, but exhibits complicated fluctuations in speed amounting to several parts in 10(exp 8) [corresponding to a variation of several milliseconds (ms) in the Length Of the Day (LOD) and about one part in 10(exp 6) in the orientation of the rotation axis relative to the solid Earth's axis of figure (polar motion). These changes occur over a broad spectrum of time scales, ranging from hours to centuries and longer, reflecting the fact that they are produced by a wide variety of geophysical and astronomical processes. Geodetic observations of Earth rotation changes thus provide insights into the geophysical processes illustrated, which are often difficult to obtain by other means. In addition, these measurements are required for engineering purposes. Theoretical studies of Earth rotation variations are based on the application of Euler's dynamical equations to the problem of finding the response of slightly deformable solid Earth to variety of surface and internal stresses.
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Pre-mare cratering and early solar system history
International Nuclear Information System (INIS)
Wetherill, G.W.
1974-01-01
An evaluation of the application of the high extra-lunar flux in pre-mare times to more general problems of early solar system history is attempted by combining the results of dynamic studies with lunar chronological data. Dynamical studies permit separate evaluation of the possible sources for both the normal flux during the first 600 m.y. years of lunar history as well as the peak which apparently occurred 4.0 b.y. ago. Dynamical studies have been carried out in order to determine the extent to which a heliocentric flux could be confined to the Moon (and Earth). A Monte Carlo method has been used to calculate the relative impact rates of planet-crossing bodies with the moon and the terrestrial planets. It is concluded that the time-variation of the flux on these planets is closely related to that on the moon
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The Alaska Education and Research Towards Health (EARTH) Study: cancer risk factors.
Lanier, Anne P; Redwood, Diana G; Kelly, Janet J
2012-04-01
The Alaska Education and Research Towards Health (EARTH) Study assessed cancer risk among 3,821 Alaska Native people (AN). We present the prevalence of selected cancer risk factors and comparison with Healthy People 2010 goals. Participants completed extensive computer-assisted self-administered questionnaires on diet, physical activity, tobacco and alcohol use, cancer screening, family history of cancer, and environmental exposures. Measurement data were collected on blood pressure, height, weight, waist/hip circumference, fasting serum lipids, and glucose. Cancer risk factors are high for the Alaska EARTH study population. For all risk factors studied except for vegetable consumption, Alaska EARTH Study participants did not meet Healthy People 2010 goals. This study is unique in providing questionnaire and measurement data of cancer risk factors on a larger study sample than any previous study among AN living in Alaska. Data show that the prevalence of most cancer risk factors exceeded national recommendations. Given the disease disparities that exist for the AN population, these data provide important baseline data that can be used to target health interventions and reduce health disparities.
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NASA's Earth Science Enterprise: Future Science Missions, Objectives and Challenges
Habib, Shahid
1998-01-01
NASA has been actively involved in studying the planet Earth and its changing environment for well over thirty years. Within the last decade, NASA's Earth Science Enterprise has become a major observational and scientific element of the U.S. Global Change Research Program. NASA's Earth Science Enterprise management has developed a comprehensive observation-based research program addressing all the critical science questions that will take us into the next century. Furthermore, the entire program is being mapped to answer five Science Themes (1) land-cover and land-use change research (2) seasonal-to-interannual climate variability and prediction (3) natural hazards research and applications (4) long-term climate-natural variability and change research and (5) atmospheric ozone research. Now the emergence of newer technologies on the horizon and at the same time continuously declining budget environment has lead to an effort to refocus the Earth Science Enterprise activities. The intent is not to compromise the overall scientific goals, but rather strengthen them by enabling challenging detection, computational and space flight technologies those have not been practically feasible to date. NASA is planning faster, cost effective and relatively smaller missions to continue the science observations from space for the next decade. At the same time, there is a growing interest in the world in the remote sensing area which will allow NASA to take advantage of this by building strong coalitions with a number of international partners. The focus of this presentation is to provide a comprehensive look at the NASA's Earth Science Enterprise in terms of its brief history, scientific objectives, organization, activities and future direction.
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An Earth-sized planet with an Earth-like density
DEFF Research Database (Denmark)
Pepe, Francesco; Cameron, Andrew Collier; Latham, David W.
2013-01-01
significantly larger than the Earth. Recently, the planet Kepler-78b was discovered(8) and found to have a radius of only 1.16R(circle plus). Here we report that the mass of this planet is 1.86 Earth masses. The resulting mean density of the planet is 5.57 g cm(-3), which is similar to that of the Earth...
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Contextualizing Earth Science Professional Development Courses for Geoscience Teachers in Boston
Chen, R. F.; Pelletier, P.; Dorsen, J.; Douglas, E. M.; Pringle, M. S.; Karp, J.
2009-12-01
Inquiry-based, hands-on, graduate content courses have been developed specifically for Boston Public School middle school teachers of Earth Science. Earth Science I: Weather and Water and Earth Science II: The Solid Earth--Earth History and Planetary Systems have been taught a total of seven times to over 120 teachers. Several key attributes to these successful courses have been identified, including co-instruction by a university professor and a high school and a middle school teacher that are familiar with the Boston curriculum, use of hands-on activities that are closed related to those used in the Boston curriculum, pre- and post-course local field trips, and identification of key learning objectives for each day. This model of professional development was developed over several years in all disciplines (Earth Science, Physics, Biology, Chemistry) by the Boston Science Partnership (BSP), an NSF-funded Math Science Partnership program. One of the core strategies of the BSP is these Contextualized Content Courses (CCC), graduate level, lab-based courses taught at either UMass Boston or Northeastern University during summer intensive or semester formats. Two of the eleven courses developed under the grant are Earth Science I & II. This presentation shares the model of the CCC, the impact on teacher participants, the value of these courses for the professor, and lessons learned for successful professional development. Findings about the courses’ impact and effectiveness come from our external evaluation by the Program Evaluation Research Group (PERG). The combination of content and modeling good instructional practices have many positive outcomes for teachers, including increased self-efficacy in science understanding and teaching, positive impacts on student achievement, and teacher shifts from more traditional, more lecture-based instructional models to more inquiry approaches. STEM faculty members become involved in science education and learn and practice new
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Mendell, Wendell
1990-01-01
The author relates the history of the human exploration initiative from a personal perspective from the 1961 J. F. Kennedy initiative to land a man on the moon up to 1986 when a memo was circulated from NASA Headquarters to its employees which stated as a major goal the expansion of the human presence beyond Earth into the solar system. The pivotal role of life support research is woven into this personalized history.
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International Nuclear Information System (INIS)
Yagi, Takehiko
2014-01-01
History of the study of the Earth's deep interior was reviewed. In order to understand Earth's deep interior from the view point of materials science, X-ray diffraction under high pressure and high temperature played very important role. Use of synchrotron radiation dramatically advanced this experimental technique and it is now possible to make precise X-ray study under the P-T conditions corresponding even to the center of the Earth. In order to clarify the behavior of light elements such as hydrogen, however, studies using neutron diffraction are also required. A new neutron beam line dedicated for high-pressure science is constructed at J-PARC and is now ready for use. (author)
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Fluvial geomorphology on Earth-like planetary surfaces: A review.
Baker, Victor R; Hamilton, Christopher W; Burr, Devon M; Gulick, Virginia C; Komatsu, Goro; Luo, Wei; Rice, James W; Rodriguez, J A P
2015-09-15
Morphological evidence for ancient channelized flows (fluvial and fluvial-like landforms) exists on the surfaces of all of the inner planets and on some of the satellites of the Solar System. In some cases, the relevant fluid flows are related to a planetary evolution that involves the global cycling of a volatile component (water for Earth and Mars; methane for Saturn's moon Titan). In other cases, as on Mercury, Venus, Earth's moon, and Jupiter's moon Io, the flows were of highly fluid lava. The discovery, in 1972, of what are now known to be fluvial channels and valleys on Mars sparked a major controversy over the role of water in shaping the surface of that planet. The recognition of the fluvial character of these features has opened unresolved fundamental questions about the geological history of water on Mars, including the presence of an ancient ocean and the operation of a hydrological cycle during the earliest phases of planetary history. Other fundamental questions posed by fluvial and fluvial-like features on planetary bodies include the possible erosive action of large-scale outpourings of very fluid lavas, such as those that may have produced the remarkable canali forms on Venus; the ability of exotic fluids, such as methane, to create fluvial-like landforms, as observed on Saturn's moon, Titan; and the nature of sedimentation and erosion under different conditions of planetary surface gravity. Planetary fluvial geomorphology also illustrates fundamental epistemological and methodological issues, including the role of analogy in geomorphological/geological inquiry.
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Volcano-ice interaction as a microbial habitat on Earth and Mars.
Cousins, Claire R; Crawford, Ian A
2011-09-01
Volcano-ice interaction has been a widespread geological process on Earth that continues to occur to the present day. The interaction between volcanic activity and ice can generate substantial quantities of liquid water, together with steep thermal and geochemical gradients typical of hydrothermal systems. Environments available for microbial colonization within glaciovolcanic systems are wide-ranging and include the basaltic lava edifice, subglacial caldera meltwater lakes, glacier caves, and subsurface hydrothermal systems. There is widespread evidence of putative volcano-ice interaction on Mars throughout its history and at a range of latitudes. Therefore, it is possible that life on Mars may have exploited these habitats, much in the same way as has been observed on Earth. The sedimentary and mineralogical deposits resulting from volcano-ice interaction have the potential to preserve evidence of any indigenous microbial populations. These include jökulhlaup (subglacial outflow) sedimentary deposits, hydrothermal mineral deposits, basaltic lava flows, and subglacial lacustrine deposits. Here, we briefly review the evidence for volcano-ice interactions on Mars and discuss the geomicrobiology of volcano-ice habitats on Earth. In addition, we explore the potential for the detection of these environments on Mars and any biosignatures these deposits may contain.
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Banquet Talk: The Fallen Sky: An Intimate History of Shooting Stars
Cokinos, Chris
2010-10-01
Christopher Cokinos will read from his book The Fallen Sky: An Intimate History of Shooting Stars, which blends folklore, history, science and memoir in an exploration--literal and metaphoric--of the passions that drive meteorite hunters. From Kansas to Greenland, from Utah to Antarctica, Cokinos crossed the globe to follow in the footsteps of such famed meteorite hunters and scientists as Robert Peary, Harvey Nininger and Eugene Shoemaker. Cokinos himself hunted meteorites as part of the NSF-funded Antarctic Search for Meteorites expedition in 2003-2004. Seed Magazine said this of his book: ``When Cokinos isn't chronicling the solar system's origins or recounting obsessive tales of explorers trekking to the ends of the Earth in pursuit of exotic rocks from the sky, he's telling the reader about the dissolution of his first marriage or his struggles with depression. But this unflinching introspection sets the stage for Cokinos' transformation, as he delves deeper into his subject and grasps the profound links between shooting stars and life here on Earth.'' Cokinos teaches at Utah State University, is the author of Hope Is the Thing with Feathers, also from Tarcher/Penguin, and has had work in the New York Times, the Los Angeles Times, the American Scholar and elsewhere.
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EarthLabs - Investigating Hurricanes: Earth's Meteorological Monsters
McDaris, J. R.; Dahlman, L.; Barstow, D.
2007-12-01
Earth science is one of the most important tools that the global community needs to address the pressing environmental, social, and economic issues of our time. While, at times considered a second-rate science at the high school level, it is currently undergoing a major revolution in the depth of content and pedagogical vitality. As part of this revolution, labs in Earth science courses need to shift their focus from cookbook-like activities with known outcomes to open-ended investigations that challenge students to think, explore and apply their learning. We need to establish a new model for Earth science as a rigorous lab science in policy, perception, and reality. As a concerted response to this need, five states, a coalition of scientists and educators, and an experienced curriculum team are creating a national model for a lab-based high school Earth science course named EarthLabs. This lab course will comply with the National Science Education Standards as well as the states' curriculum frameworks. The content will focus on Earth system science and environmental literacy. The lab experiences will feature a combination of field work, classroom experiments, and computer access to data and visualizations, and demonstrate the rigor and depth of a true lab course. The effort is being funded by NOAA's Environmental Literacy program. One of the prototype units of the course is Investigating Hurricanes. Hurricanes are phenomena which have tremendous impact on humanity and the resources we use. They are also the result of complex interacting Earth systems, making them perfect objects for rigorous investigation of many concepts commonly covered in Earth science courses, such as meteorology, climate, and global wind circulation. Students are able to use the same data sets, analysis tools, and research techniques that scientists employ in their research, yielding truly authentic learning opportunities. This month-long integrated unit uses hurricanes as the story line by
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Sky of ash, earth of ash: A brief history of fire in the United States
International Nuclear Information System (INIS)
Pyne, S.J.
1991-01-01
In this chapter, the author describes the history of fire practices in the United States from early man to the present. The effects of these practices on climates, natural resources, on ecological succession, and the establishment of environmental policy are discussed
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Biological and geophysical feedbacks with fire in the Earth system
Archibald, S.; Lehmann, C. E. R.; Belcher, C. M.; Bond, W. J.; Bradstock, R. A.; Daniau, A.-L.; Dexter, K. G.; Forrestel, E. J.; Greve, M.; He, T.; Higgins, S. I.; Hoffmann, W. A.; Lamont, B. B.; McGlinn, D. J.; Moncrieff, G. R.; Osborne, C. P.; Pausas, J. G.; Price, O.; Ripley, B. S.; Rogers, B. M.; Schwilk, D. W.; Simon, M. F.; Turetsky, M. R.; Van der Werf, G. R.; Zanne, A. E.
2018-03-01
Roughly 3% of the Earth’s land surface burns annually, representing a critical exchange of energy and matter between the land and atmosphere via combustion. Fires range from slow smouldering peat fires, to low-intensity surface fires, to intense crown fires, depending on vegetation structure, fuel moisture, prevailing climate, and weather conditions. While the links between biogeochemistry, climate and fire are widely studied within Earth system science, these relationships are also mediated by fuels—namely plants and their litter—that are the product of evolutionary and ecological processes. Fire is a powerful selective force and, over their evolutionary history, plants have evolved traits that both tolerate and promote fire numerous times and across diverse clades. Here we outline a conceptual framework of how plant traits determine the flammability of ecosystems and interact with climate and weather to influence fire regimes. We explore how these evolutionary and ecological processes scale to impact biogeochemical and Earth system processes. Finally, we outline several research challenges that, when resolved, will improve our understanding of the role of plant evolution in mediating the fire feedbacks driving Earth system processes. Understanding current patterns of fire and vegetation, as well as patterns of fire over geological time, requires research that incorporates evolutionary biology, ecology, biogeography, and the biogeosciences.
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Red-emitting alkaline-earth rare-earth pentaoxometallates powders ...
Indian Academy of Sciences (India)
Moisture-insensitive metal carboxylates that are mostly liquids at room temperature have been first applied to ... alkaline-earth ion, or possibly even a rare-earth ion and alkali metal ... sion spectra of the powders were recorded on a fluorescent.
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Earth - South America (first frame of Earth Spin Movie)
1990-01-01
This color image of the Earth was obtained by Galileo at about 6:10 a.m. Pacific Standard Time on Dec. 11, 1990, when the spacecraft was about 1.3 million miles from the planet during the first of two Earth flybys on its way to Jupiter. The color composite used images taken through the red, green and violet filters. South America is near the center of the picture, and the white, sunlit continent of Antarctica is below. Picturesque weather fronts are visible in the South Atlantic, lower right. This is the first frame of the Galileo Earth spin movie, a 500- frame time-lapse motion picture showing a 25-hour period of Earth's rotation and atmospheric dynamics.
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Potassium-argon dating: an access to the dynamics and the history of the Planet Earth
International Nuclear Information System (INIS)
Gillot, P.Y.
1993-01-01
Today, scientists, concerned by the history and the evolution of our planet, have a wide range of dating methods. Among these, potassium-argon dating with a field of application that now largely covers that of dating by thermoluminescence or by carbon 14
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"Thinking about a Sustainable Earth"
Ikeshita, Makoto
2014-05-01
1.Introduction The Course of study for Junior high school teaching was changed in 2008 in Japan. We should especially mention about this change that ESD, "Education for Sustainable Development," was written as a point of view. ESD is a kind of educations that is studied with a target for a region and that aims at reorganize of consciousness through thinking of how to be a better region. ESD's view was written for Social studies, Science, Foreign Languages, Health and Physical Education, Home Economics and Technical Arts, and the Period for Integrated Studies. Of these subjects, Social studies are the one of core subjects. Social studies for Junior high school consist of Geography, History and Civics. "Problem of us and international society" is the last part of Civics. Teacher helps students to understand international society deeply and think about the role of our country for it. Students research many problems (global environment, resources and energy, poverty etc.) and organize their thoughts on how make a better society as a part of the human family. I taught them to think about how to solve many themes like religious problems, terrorism problems, the North-South problems, and resource and energy problems. It is my practice to let them think about what they should do to solve the global warming problem. 2.The truth of my class I pointed out to the students that the length of summer time in Japan is increasing, and we can anticipate it will continue to increase in the future. After that, I explained to them that occurrence of sudden, heavy downpour of rain is increasing and helped them understand the process of this kind of downpour through some diagrams and pictures. I helped them understand the context of this increase of the length of summer time and heavy downpour within the whole earth's ecosystem. Such increases as these things are causing global warming. I asked them to think about what are the possible problems if global warming progresses. The ideas the
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Building a Dashboard of the Planet with Google Earth and Earth Engine
Moore, R. T.; Hancher, M.
2016-12-01
In 2005 Google Earth, a popular 3-D virtual globe, was first released. Scientists immediately recognized how it could be used to tell stories about the Earth. From 2006 to 2009, the "Virtual Globes" sessions of AGU included innovative examples of scientists and educators using Google Earth, and since that time it has become a commonplace tool for communicating scientific results. In 2009 Google Earth Engine, a cloud-based platform for planetary-scale geospatial analysis, was first announced. Earth Engine was initially used to extract information about the world's forests from raw Landsat data. Since then, the platform has proven highly effective for general analysis of georeferenced data, and users have expanded the list of use cases to include high-impact societal issues such as conservation, drought, disease, food security, water management, climate change and environmental monitoring. To support these use cases, the platform has continuously evolved with new datasets, analysis functions, and user interface tools. This talk will give an overview of the latest Google Earth and Earth Engine functionality that allow partners to understand, monitor and tell stories about of our living, breathing Earth. https://earth.google.com https://earthengine.google.com
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Inaugeral lecture - Meteorite impacts on Earth and on the Earth ...
African Journals Online (AJOL)
There is some controversial evidence for the theory that the first life on Earth itself may have been transported here on meteorites from Mars. The possibility of a major meteorite impact on Earth in the near future emphasizes the dramatic nature of these recent discoveries, which are having deep impacts in the Earth sciences ...
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From tectonics to tractors: New insight into Earth's changing surface
Larsen, I. J.
2017-12-01
Weathering and erosion of rock and the transport of sediment continually modify Earth's surface. The transformation and transfer of material by both natural and anthropogenic processes drives global cycles and influences the habitability of our planet. By quantitatively linking erosional and depositional landforms to the processes that form them, we better understand how Earth's surface will evolve in the future, and gain the ability to look into the past to recognize how planetary surfaces evolved when environments were drastically different than today. Many of the recent advances in our understanding of the processes that influence landscape evolution have been driven by the development and application of tools such as cosmogenic nuclides, computational models, and digital topographic data. Here I present results gleaned from applying these tools to a diverse set of landscapes, where erosion is driven by factors ranging from tectonics to tractors, to provide insight into the mechanics, chemistry, and history of Earth's changing surface. I will first examine the landslide response of hillslopes in the Himalaya to spatial gradients in tectonic forcing to assess the paradigm of threshold hillslopes. Second, I will present soil production and chemical weathering rates measured in the Southern Alps of New Zealand to determine the relationship between physical erosion and chemical weathering in one of Earth's most rapidly uplifting landscapes, and discuss the implications for proposed links between mountain uplift and global climate. Third, I will discuss results from numerical flood simulations used to explore the interplay between outburst flood hydraulics and canyon incision in the Channeled Scablands of eastern Washington, and explore the implications for reconstructing discharge in flood-carved canyons on Earth and Mars. Finally, I will present new work that couples high resolution spectral and topographic data to estimate the spatial extent of agriculturally
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West, Phillip B [Idaho Falls, ID; Novascone, Stephen R [Idaho Falls, ID; Wright, Jerry P [Idaho Falls, ID
2011-09-27
Earth analysis methods, subsurface feature detection methods, earth analysis devices, and articles of manufacture are described. According to one embodiment, an earth analysis method includes engaging a device with the earth, analyzing the earth in a single substantially lineal direction using the device during the engaging, and providing information regarding a subsurface feature of the earth using the analysis.
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Obliquity histories of Earth and Mars: Influence of inertial and dissipative core-mantle coupling
International Nuclear Information System (INIS)
Bills, B.G.
1990-01-01
For both the Earth and Mars, secular variations in the angular separation of the spin axis from the orbit normal are suspected of driving major climatic changes. There is considerable interest in determining the amplitude and timing of these obliquity variations. If the orientation of the orbital plane were inertially fixed, the spin axis would simply precess around the orbit at a fixed obliquity and at a uniform angular rate. The precession rate parameter depends on the principal moments of inertia and rotation rate of the perturbed body, and on the gravitational masses and semiminor axes of the perturbing bodies. For Mars, the precession rate is not well known, but probably lies in the interval 8 to 10 arcsec/year. In the rigid body case, the spin axis still attempts to precess about the instantaneous orbit normal, but now the obliquity varies. The hydrostatic figure of a planet represents a compromise between gravitation, which attempts to attain spherical symmetry, and rotation, which prefers cylindrical symmetry. Due to their higher mean densities the cores of the Earth and Mars will be more nearly spherical than the outer layers of these planets. On short time scales it is appropriate to consider the core to be an inviscid fluid. The inertial coupling provided by this mechanism is effective whenever the ellipticicy of the container exceeds the ratio of precessional to rotational rates. If the mantle were actually rigid, this would be an extremely effective type of coupling. However, on sufficiently long time scales, the mantle will deform viscously and can accommodate the motions of the core fluid. A fundamentally different type of coupling is provided by electromagnetic or viscous torques. This type of coupling is likely to be most important on longer time scales
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The Lifeworld Earth and a Modelled Earth
Juuti, Kalle
2014-01-01
The goal of this paper is to study the question of whether a phenomenological view of the Earth could be empirically endorsed. The phenomenological way of thinking considers the Earth as a material entity, but not as an object as viewed in science. In the learning science tradition, tracking the process of the conceptual change of the shape of the…
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Eighth Planta Europa Conference «Save Plants for Earth's Future» (Kiev, Ukraine
Directory of Open Access Journals (Sweden)
Alexander N. Tashev
2017-08-01
Full Text Available This paper presents information about the Eighth Planta Europa Conference (Save plants for Earth's future (22–26 May 2017, Kiev, Ukraine. We presented brief data on the history of previous Planta Europa meetings. We presented general information about the main events of the Conference, its thematic areas represented by oral and poster presentations. Brief data on the number of participants, presentations and excursions into botanical gardens of Kiev are presented.
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Earth Science Data Analysis in the Era of Big Data
Kuo, K.-S.; Clune, T. L.; Ramachandran, R.
2014-01-01
Anyone with even a cursory interest in information technology cannot help but recognize that "Big Data" is one of the most fashionable catchphrases of late. From accurate voice and facial recognition, language translation, and airfare prediction and comparison, to monitoring the real-time spread of flu, Big Data techniques have been applied to many seemingly intractable problems with spectacular successes. They appear to be a rewarding way to approach many currently unsolved problems. Few fields of research can claim a longer history with problems involving voluminous data than Earth science. The problems we are facing today with our Earth's future are more complex and carry potentially graver consequences than the examples given above. How has our climate changed? Beside natural variations, what is causing these changes? What are the processes involved and through what mechanisms are these connected? How will they impact life as we know it? In attempts to answer these questions, we have resorted to observations and numerical simulations with ever-finer resolutions, which continue to feed the "data deluge." Plausibly, many Earth scientists are wondering: How will Big Data technologies benefit Earth science research? As an example from the global water cycle, one subdomain among many in Earth science, how would these technologies accelerate the analysis of decades of global precipitation to ascertain the changes in its characteristics, to validate these changes in predictive climate models, and to infer the implications of these changes to ecosystems, economies, and public health? Earth science researchers need a viable way to harness the power of Big Data technologies to analyze large volumes and varieties of data with velocity and veracity. Beyond providing speedy data analysis capabilities, Big Data technologies can also play a crucial, albeit indirect, role in boosting scientific productivity by facilitating effective collaboration within an analysis environment
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Uncovering History for Future History Teachers
Fischer, Fritz
2010-01-01
The art of history teaching is at a crossroads. Recent scholarship focuses on the need to change the teaching of history so students can better learn history, and insists that history teachers must move beyond traditional structures and methods of teaching in order to improve their students' abilities to think with history. This article presents…
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Atmospheric acceleration and Earth-expansion deceleration of the Earth rotation
Directory of Open Access Journals (Sweden)
Wenbin Shen
2017-11-01
Full Text Available Previous studies suggest that tidal friction gives rise to the secular deceleration of the Earth rotation by a quantity of about 2.25 ms/cy. Here we just consider additional contributions to the secular Earth rotation deceleration. Atmospheric solar semi-diurnal tide has a small amplitude and certain amount of phase lead. This periodic global air-mass excess distribution exerts a quasi-constant torque to accelerate the Earth's spin rotation. Using an updated atmospheric tide model, we re-estimate the amounts of this atmospheric acceleration torque and corresponding energy input, of which the associated change rate in LOD (length of day is −0.1 ms/cy. In another aspect, evidences from space-geodesy and sea level rise observations suggest that Earth expands at a rate of 0.35 mm/yr in recent decades, which gives rise to the increase of LOD at rate of 1.0 ms/cy. Hence, if the previous estimate due to the tidal friction is correct, the secular Earth rotation deceleration due to tidal friction and Earth expansion should be 3.15 ms/cy.
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International Nuclear Information System (INIS)
1984-01-01
The conference was held from September 12 to 13, 1984 in Jetrichovice, Czechoslovakia. The participants heard 16 papers of which 4 were inputted in INIS. These papers dealt with industrial separation processes of rare earths, the use of chemical methods of separation from the concentrate of apatite and bastnesite, the effect of the relative permittivity of solvents in the elution of rare earth elements from a cation exchanger, and the determination of the content of different rare earth elements using X-ray fluorescence analysis and atomic absorption spectroscopy. (E.S.)
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Natural history collections as windows on evolutionary processes.
Holmes, Michael W; Hammond, Talisin T; Wogan, Guinevere O U; Walsh, Rachel E; LaBarbera, Katie; Wommack, Elizabeth A; Martins, Felipe M; Crawford, Jeremy C; Mack, Katya L; Bloch, Luke M; Nachman, Michael W
2016-02-01
Natural history collections provide an immense record of biodiversity on Earth. These repositories have traditionally been used to address fundamental questions in biogeography, systematics and conservation. However, they also hold the potential for studying evolution directly. While some of the best direct observations of evolution have come from long-term field studies or from experimental studies in the laboratory, natural history collections are providing new insights into evolutionary change in natural populations. By comparing phenotypic and genotypic changes in populations through time, natural history collections provide a window into evolutionary processes. Recent studies utilizing this approach have revealed some dramatic instances of phenotypic change over short timescales in response to presumably strong selective pressures. In some instances, evolutionary change can be paired with environmental change, providing a context for potential selective forces. Moreover, in a few cases, the genetic basis of phenotypic change is well understood, allowing for insight into adaptive change at multiple levels. These kinds of studies open the door to a wide range of previously intractable questions by enabling the study of evolution through time, analogous to experimental studies in the laboratory, but amenable to a diversity of species over longer timescales in natural populations. © 2016 John Wiley & Sons Ltd.
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Rare earths and rare earth alloys electrolytic preparation process and device for this process
International Nuclear Information System (INIS)
Seon, F.; Barthole, G.
1986-01-01
Electrolysis of a molten salt of rare earth or rare earth alloy for preparation of the metal or alloy is described. The molten salt bath comprises at least a rare earth chloride, at least an alkaline or alkaline earth chloride and at least an alkaline or alkaline earth fluoride [fr
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UKRAINIAN HUT - RETURN TO THE HISTORY
Directory of Open Access Journals (Sweden)
BABENKO V. A.
2016-06-01
Dnieper region. Conclusions. Having the honor to participate at least in a way this is extremely important and profound book about Ukraine and Ukrainians want to complete their review of our words of prominent Ukrainian historian and culture expert Miroslav Popovich: "... Ukraine makes people not blood and earth. Ukraine makes them and the culture in which they are involved ... Ukraine - people who maintain and develop from generation to generation certain standard of living, values and norms, life and culture ... Buildings, books, music, live only when they read, perceive understand. What a huge and bottomless that dumb us the walls of ancient monasteries and pages of new and old books - silent until we find the key to understanding and empathy - all that is a national culture, without which callous earth and stranger blood ... options accident and loss of values lot revival only one option. This careful preservation of all that served in our history, truth, goodness and beauty. "
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The "Earth Physics" Workshops Offered by the Earth Science Education Unit
Davies, Stephen
2012-01-01
Earth science has a part to play in broadening students' learning experience in physics. The Earth Science Education Unit presents a range of (free) workshops to teachers and trainee teachers, suggesting how Earth-based science activities, which show how we understand and use the planet we live on, can easily be slotted into normal science…
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Modeling of the Earth's gravity field using the New Global Earth Model (NEWGEM)
Kim, Yeong E.; Braswell, W. Danny
1989-01-01
Traditionally, the global gravity field was described by representations based on the spherical harmonics (SH) expansion of the geopotential. The SH expansion coefficients were determined by fitting the Earth's gravity data as measured by many different methods including the use of artificial satellites. As gravity data have accumulated with increasingly better accuracies, more of the higher order SH expansion coefficients were determined. The SH representation is useful for describing the gravity field exterior to the Earth but is theoretically invalid on the Earth's surface and in the Earth's interior. A new global Earth model (NEWGEM) (KIM, 1987 and 1988a) was recently proposed to provide a unified description of the Earth's gravity field inside, on, and outside the Earth's surface using the Earth's mass density profile as deduced from seismic studies, elevation and bathymetric information, and local and global gravity data. Using NEWGEM, it is possible to determine the constraints on the mass distribution of the Earth imposed by gravity, topography, and seismic data. NEWGEM is useful in investigating a variety of geophysical phenomena. It is currently being utilized to develop a geophysical interpretation of Kaula's rule. The zeroth order NEWGEM is being used to numerically integrate spherical harmonic expansion coefficients and simultaneously determine the contribution of each layer in the model to a given coefficient. The numerically determined SH expansion coefficients are also being used to test the validity of SH expansions at the surface of the Earth by comparing the resulting SH expansion gravity model with exact calculations of the gravity at the Earth's surface.
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How Did the Universe Make People? A Brief History of the Universe from the Beginning to the End
Mather, John C.
2009-01-01
Astronomers are beginning to know the easy part: How did the Big Bang make stars and galaxies and the chemical elements? How did solar systems form and evolve? How did the Earth and the Moon form, and how did water and carbon come to the Earth? Geologists are piecing together the history of the Earth, and biologists are coming to know the history and process of life from the earliest times. But is our planet the only life-supporting place in the universe, or are there many? Astronomers are working on that too. I will tell the story of the discovery of the Big Bang by Edwin Hubble, and how the primordial heat radiation tells the details of that universal explosion. I will tell how the James Webb Space Telescope will extend the discoveries of the Hubble Space Telescope to ever greater distances, will look inside dust clouds to see stars being born today, will measure planets around other stars, and examine the dwarf planets in the outer Solar System. I will show concepts for great new space telescopes to follow the JWST and how they could use future moon rockets to hunt for signs of life on planets around other stars.
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Beautiful Earth: Inspiring Native American students in Earth Science through Music, Art and Science
Casasanto, V.; Rock, J.; Hallowell, R.; Williams, K.; Angell, D.; Beautiful Earth
2011-12-01
The Beautiful Earth program, awarded by NASA's Competitive Opportunities in Education and Public Outreach for Earth and Space Science (EPOESS), is a live multi-media performance at partner science centers linked with hands-on workshops featuring Earth scientists and Native American experts. It aims to inspire, engage and educate diverse students in Earth science through an experience of viewing the Earth from space as one interconnected whole, as seen through the eyes of astronauts. The informal education program is an outgrowth of Kenji Williams' BELLA GAIA Living Atlas Experience (www.bellagaia.com) performed across the globe since 2008 and following the successful Earth Day education events in 2009 and 2010 with NASA's DLN (Digital Learning Network) http://tinyurl.com/2ckg2rh. Beautiful Earth takes a new approach to teaching, by combining live music and data visualizations, Earth Science with indigenous perspectives of the Earth, and hands-on interactive workshops. The program will utilize the emotionally inspiring multi-media show as a springboard to inspire participants to learn more about Earth systems and science. Native Earth Ways (NEW) will be the first module in a series of three "Beautiful Earth" experiences, that will launch the national tour at a presentation in October 2011 at the MOST science museum in collaboration with the Onandaga Nation School in Syracuse, New York. The NEW Module will include Native American experts to explain how they study and conserve the Earth in their own unique ways along with hands-on activities to convey the science which was seen in the show. In this first pilot run of the module, 110 K-12 students with faculty and family members of the Onandaga Nations School will take part. The goal of the program is to introduce Native American students to Earth Sciences and STEM careers, and encourage them to study these sciences and become responsible stewards of the Earth. The second workshop presented to participants will be the
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Building a better search engine for earth science data
Armstrong, E. M.; Yang, C. P.; Moroni, D. F.; McGibbney, L. J.; Jiang, Y.; Huang, T.; Greguska, F. R., III; Li, Y.; Finch, C. J.
2017-12-01
Free text data searching of earth science datasets has been implemented with varying degrees of success and completeness across the spectrum of the 12 NASA earth sciences data centers. At the JPL Physical Oceanography Distributed Active Archive Center (PO.DAAC) the search engine has been developed around the Solr/Lucene platform. Others have chosen other popular enterprise search platforms like Elasticsearch. Regardless, the default implementations of these search engines leveraging factors such as dataset popularity, term frequency and inverse document term frequency do not fully meet the needs of precise relevancy and ranking of earth science search results. For the PO.DAAC, this shortcoming has been identified for several years by its external User Working Group that has assigned several recommendations to improve the relevancy and discoverability of datasets related to remotely sensed sea surface temperature, ocean wind, waves, salinity, height and gravity that comprise a total count of over 500 public availability datasets. Recently, the PO.DAAC has teamed with an effort led by George Mason University to improve the improve the search and relevancy ranking of oceanographic data via a simple search interface and powerful backend services called MUDROD (Mining and Utilizing Dataset Relevancy from Oceanographic Datasets to Improve Data Discovery) funded by the NASA AIST program. MUDROD has mined and utilized the combination of PO.DAAC earth science dataset metadata, usage metrics, and user feedback and search history to objectively extract relevance for improved data discovery and access. In addition to improved dataset relevance and ranking, the MUDROD search engine also returns recommendations to related datasets and related user queries. This presentation will report on use cases that drove the architecture and development, and the success metrics and improvements on search precision and recall that MUDROD has demonstrated over the existing PO.DAAC search
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Data-driven exploration of copper mineralogy and its application to Earth's near-surface oxidation
Morrison, S. M.; Eleish, A.; Runyon, S.; Prabhu, A.; Fox, P. A.; Ralph, J.; Golden, J. J.; Downs, R. T.; Liu, C.; Meyer, M.; Hazen, R. M.
2017-12-01
Earth's atmospheric composition has changed radically throughout geologic history.1,2 The oxidation of our atmosphere, driven by biology, began with the Great Oxidation Event (GOE) 2.5 Ga and has heavily influenced Earth's near surface mineralogy. Therefore, temporal trends in mineral occurrence elucidate large and small scale geologic and biologic processes. Cu, and other first-row transition elements, are of particular interest due to their variation in valance state and sensitivity to ƒO2. Widespread formation of oxidized Cu mineral species (Cu2+) would not have been possible prior to the GOE and we have found that the proportion of oxidized Cu minerals increased steadily with the increase in atmospheric O2 on Earth's surface (see Fig. 1). To better characterize the changes in Cu mineralogy through time, we have employed advanced analytical and visualization methods. These techniques rely on large and growing mineral databases (e.g., rruff.info, mindat.org, earthchem.org, usgs.gov) and allow us to quantify and visualize multi-dimensional trends.5
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Directory of Open Access Journals (Sweden)
A G Rodnikov
2009-04-01
Full Text Available Fifty years have passed since the International Geophysical Year (IGY of 1957.58, one of the most important and noble initiatives in the history of science and in the history of humanity in general. IGY became the model for subsequent international scientific initiatives in various fields of solid Earth research, including the Upper Mantle Project (1961.71, the Geodynamic Project (1971.80, the Geotraverse Project (1987.2003, and the "InterMARGINS" Project (2003. The Russian investigations as part of the Geotraverse Project and "InterMARGINS" were aimed at research into the deep structure of the continental margins of East Eurasia, which are characterized by high seismicity, volcanism, and natural cataclysms hazardous to people living there.
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Extraction of rare earths from iron-rich rare earth deposits
Bisaka, K.; Thobadi, I.C.; Pawlik, C.
2017-01-01
Rare earth metals are classified as critical metals by the United Nations, as they have found wide application in the fabrication of magnets, particularly those used in green energy technologies which mitigate global warming. Processing of ores containing rare earth elements is complex, and differs according to the nature of each ore. In the conventional process, run of mine (ROM) ores are processed in a physical separation plant to produce a concentrate from which rare earth elements are ext...
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Memories of Earth Formation in the Modern Mantle: W Isotopic Composition of Flood Basalt Lavas
Rizo Garza, H. L.; Walker, R. J.; Carlson, R.; Horan, M. F.; Mukhopadhyay, S.; Francis, D.; Jackson, M. G.
2015-12-01
Four and a half billion years of geologic activity has overprinted much of the direct evidence for processes involved in Earth's formation and its initial chemical differentiation. Xenon isotopic ratios [1] and 3He/22Ne ratios [2] suggest that heterogeneities formed during Earth's accretion have been preserved to the present time. New opportunities to learn about early Earth history have opened up with the development of analytical techniques that allow high precision analysis of short-lived isotopic systems. The Hf-W system (t½ = 8.9 Ma) is particularly valuable for studying events that occurred during the first ~50 Ma of Solar System history. Here we report new data for ~ 60 Ma Baffin Bay and ~ 120 Ma Ontong Java Plateau lava samples. Both are large igneous provinces that may have sampled a primitive, less degassed deep mantle reservoir that has remained isolated since shortly after Earth formation [3,4]. Three samples analyzed have 182W/184W ratios that are 10 to 48 ppm higher than our terrestrial standard. These excesses in 182W are the highest ever measured in terrestrial rocks, and may reflect 182W ingrowth in an early-formed high Hf/W mantle domain that was produced by magma ocean differentiation [5]. Long and short-lived Sm-Nd systematics in these samples, however, are inconsistent with this hypothesis. The 182W excessses could rather reflect the derivation of these lavas from a mantle reservoir that was isolated from late accretionary additions [6]. The chondritic initial Os isotopic compositions and highly siderophile element abundances of these samples, however, are inconsistent with this interpretation. Tungsten concentrations for the Baffin Bay and Ontong Java Plateau samples range from 23 ppb to 62 ppb, and are negatively correlated with their 182W/184W ratios. We propose that the source reservoirs for these flood basalts likely formed through Hf/W fractionation caused by core-forming events occuring over a protacted time interval during Earth
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Examples of the Zeroth Theorem of the History of Science
Energy Technology Data Exchange (ETDEWEB)
Jackson, J.D.
2007-08-24
The zeroth theorem of the history of science, enunciated byE. P. Fischer, states that a discovery (rule,regularity, insight) namedafter someone (often) did not originate with that person. I present fiveexamples from physics: the Lorentz condition partial muAmu = 0 definingthe Lorentz gauge of the electromagnetic potentials; the Dirac deltafunction, delta(x); the Schumann resonances of the earth-ionospherecavity; the Weizsacker-Williams method of virtual quanta; the BMTequation of spin dynamics. I give illustrated thumbnail sketches of boththe true and reputed discoverers and quote from their "discovery"publications.
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Tse, Pui-Kwan
2011-01-01
Introduction China's dominant position as the producer of over 95 percent of the world output of rare-earth minerals and rapid increases in the consumption of rare earths owing to the emergence of new clean-energy and defense-related technologies, combined with China's decisions to restrict exports of rare earths, have resulted in heightened concerns about the future availability of rare earths. As a result, industrial countries such as Japan, the United States, and countries of the European Union face tighter supplies and higher prices for rare earths. This paper briefly reviews China's rare-earth production, consumption, and reserves and the important policies and regulations regarding the production and trade of rare earths, including recently announced export quotas. The 15 lanthanide elements-lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium (atomic numbers 57-71)-were originally known as the rare earths from their occurrence in oxides mixtures. Recently, some researchers have included two other elements-scandium and yttrium-in their discussion of rare earths. Yttrium (atomic number 39), which lies above lanthanum in transition group III of the periodic table and has a similar 3+ ion with a noble gas core, has both atomic and ionic radii similar in size to those of terbium and dysprosium and is generally found in nature with lanthanides. Scandium (atomic number 21) has a smaller ionic radius than yttrium and the lanthanides, and its chemical behavior is intermediate between that of aluminum and the lanthanides. It is found in nature with the lanthanides and yttrium. Rare earths are used widely in high-technology and clean-energy products because they impart special properties of magnetism, luminescence, and strength. Rare earths are also used in weapon systems to obtain the same properties.
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Directory of Open Access Journals (Sweden)
Kaye Reed
2009-09-01
Full Text Available Understanding the evolution of humans and our close relatives is one of the enduring scientific issues of modern times. Since the time of Charles Darwin, scientists have speculated on how and when we evolved and what conditions drove this evolutionary story. The detective work required to address these questions is necessarily interdisciplinary,involving research in anthropology, archaeology, human genetics and genomics, and the earth sciences. In addition to the difficult tasks of finding, describing, and interpreting hominin fossils (the taxonomic tribe which includes Homo sapiens and our close fossil relatives from the last 6 Ma, much of modern geological research associated with paleoanthropology involves understanding the geochronologic and paleoenvironmental context of those fossils. When were they entombed in the sediments? What were the local and regional climatic conditions that early hominins experienced? How did local (watershed scale and regional climate processes combine with regional tectonic boundary conditions to influence hominin food resources, foraging patterns, and demography? How and when did these conditions vary from humid to dry, or cool to warm? Can the history of those conditions (Vrba, 1988; Potts, 1996 be related to the evolution, diversification, stasis, or extinction of hominin species?
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International Nuclear Information System (INIS)
Wilson, G.S.; Backlund, P.W.
1992-01-01
Mission to Planet Earth (MTPE) is NASA's concept for an international science program to produce the understanding needed to predict changes in the earth's environment. NASA and its interagency and international partners will place satellites carrying advanced sensors in strategic earth orbits to gather multidisciplinary data. A sophisticated data system will process and archive an unprecedented amount of information about the earth and how it works as a system. Increased understanding of the earth system is a basic human responsibility, a prerequisite to informed management of the planet's resources and to the preservation of the global environment. 8 refs
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Tilford, Shelby G.; Asrar, Ghassem; Backlund, Peter W.
1994-01-01
Mission to Planet Earth (MTPE) is NASA's concept for an international science program to produce the understanding needed to predict changes in the Earth's environment. NASA and its interagency and international partners will place satellites carrying advanced sensors in strategic Earth orbits to gather multidisciplinary data. A sophisticated data system will process and archive an unprecedented amount of information about the Earth and how it works as a system. Increased understanding of the Earth system is a basic human responsibility, a prerequisite to informed management of the planet's resources and to the preservation of the global environment.
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Mitton, S. A.
2017-12-01
Carbon plays an unparalleled role in our lives: as the element of life, as the basis of most of society's energy, as the backbone of most new materials, and as the central focus in efforts to understand Earth's variable and uncertain climate. Yet in spite of carbon's importance, scientists remain largely ignorant of the physical, chemical, and biological behavior of many of Earth's carbon-bearing systems. The Deep Carbon Observatory (DCO) is a global research program to transform our understanding of carbon in Earth. At its heart, DCO is a community of scientists, from biologists to physicists, geoscientists to chemists, and many others whose work crosses these disciplinary lines, forging a new, integrative field of deep carbon science. As a historian of science, I specialise in the history of planetary science and astronomy since 1900. This is directed toward understanding of the history of the steps on the road to discovering the internal dynamics of our planet. Within a framework that describes the historical background to the new field of Earth System Science, I present the first history of deep carbon science. This project will identifies the key discoveries of deep carbon science. It will assess the impact of new knowledge on geochemistry, geodynamics, and geobiology. The project will lead to publication, in book form in 2019, of an illuminating narrative that will highlight the engaging human stories of many remarkable scientists and natural philosophers from whom we have learned about the complexity of Earth's internal world. On this journey of discovery we will encounter not just the pioneering researchers of deep carbon science, but also their institutions, their instrumental inventiveness, and their passion for exploration. The book is organised thematically around the four communities of the Deep Carbon Observatory: Deep Life, Extreme Physics and Chemistry, Reservoirs and Fluxes, and Deep Energy. The presentation has a gallery and list of Deep Carbon
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EarthServer: Cross-Disciplinary Earth Science Through Data Cube Analytics
Baumann, P.; Rossi, A. P.
2016-12-01
The unprecedented increase of imagery, in-situ measurements, and simulation data produced by Earth (and Planetary) Science observations missions bears a rich, yet not leveraged potential for getting insights from integrating such diverse datasets and transform scientific questions into actual queries to data, formulated in a standardized way.The intercontinental EarthServer [1] initiative is demonstrating new directions for flexible, scalable Earth Science services based on innovative NoSQL technology. Researchers from Europe, the US and Australia have teamed up to rigorously implement the concept of the datacube. Such a datacube may have spatial and temporal dimensions (such as a satellite image time series) and may unite an unlimited number of scenes. Independently from whatever efficient data structuring a server network may perform internally, users (scientist, planners, decision makers) will always see just a few datacubes they can slice and dice.EarthServer has established client [2] and server technology for such spatio-temporal datacubes. The underlying scalable array engine, rasdaman [3,4], enables direct interaction, including 3-D visualization, common EO data processing, and general analytics. Services exclusively rely on the open OGC "Big Geo Data" standards suite, the Web Coverage Service (WCS). Conversely, EarthServer has shaped and advanced WCS based on the experience gained. The first phase of EarthServer has advanced scalable array database technology into 150+ TB services. Currently, Petabyte datacubes are being built for ad-hoc and cross-disciplinary querying, e.g. using climate, Earth observation and ocean data.We will present the EarthServer approach, its impact on OGC / ISO / INSPIRE standardization, and its platform technology, rasdaman.References: [1] Baumann, et al. (2015) DOI: 10.1080/17538947.2014.1003106 [2] Hogan, P., (2011) NASA World Wind, Proceedings of the 2nd International Conference on Computing for Geospatial Research
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International Nuclear Information System (INIS)
Armstrong, R.L.
1981-01-01
The proposition that continental crust is recycled into the mantle and that the Earth is in a near-steady state with essentially constant volumes of oceans and crust through geological time is defended. Constancy of continental freeboard and uniformity of thickness of stable continental crust with age are the only two quantitative measures of crustal volume through time and these imply negligible crustal growth since 2.9 Ga B.P. Planetary analogies, Pb isotopes, atmospheric evolution, and palaeomagnetism also argue for early terrestrial differentiation. Rates of crustal growth and recycling are sufficient to reach a near-steady state over the first 1 Ga of Earth history, before widespread cratonization. Pb, Sr and Nd isotopic compositions of igneous rocks from the mantle are explainable in terms of a near-steady-state model. The recycling process can be observed on the Earth today. The observed escape of primordial 3 He from the mantle is not evidence for continuing continental differentiation or against early differentiation of the Earth. Even if nearly complete equilibrium chemical differentiation occurred at 4.6 Ga B.P., some 3 He would remain dissolved in the interior and would escape as recycling continued. (U.K.)
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Disequilibrium biosignatures over Earth history and implications for detecting exoplanet life.
Krissansen-Totton, Joshua; Olson, Stephanie; Catling, David C
2018-01-01
Chemical disequilibrium in planetary atmospheres has been proposed as a generalized method for detecting life on exoplanets through remote spectroscopy. Among solar system planets with substantial atmospheres, the modern Earth has the largest thermodynamic chemical disequilibrium due to the presence of life. However, how this disequilibrium changed over time and, in particular, the biogenic disequilibria maintained in the anoxic Archean or less oxic Proterozoic eons are unknown. We calculate the atmosphere-ocean disequilibrium in the Precambrian using conservative proxy- and model-based estimates of early atmospheric and oceanic compositions. We omit crustal solids because subsurface composition is not detectable on exoplanets, unlike above-surface volatiles. We find that (i) disequilibrium increased through time in step with the rise of oxygen; (ii) both the Proterozoic and Phanerozoic may have had remotely detectable biogenic disequilibria due to the coexistence of O 2 , N 2 , and liquid water; and (iii) the Archean had a biogenic disequilibrium caused by the coexistence of N 2 , CH 4 , CO 2 , and liquid water, which, for an exoplanet twin, may be remotely detectable. On the basis of this disequilibrium, we argue that the simultaneous detection of abundant CH 4 and CO 2 in a habitable exoplanet's atmosphere is a potential biosignature. Specifically, we show that methane mixing ratios greater than 10 -3 are potentially biogenic, whereas those exceeding 10 -2 are likely biogenic due to the difficulty in maintaining large abiotic methane fluxes to support high methane levels in anoxic atmospheres. Biogenicity would be strengthened by the absence of abundant CO, which should not coexist in a biological scenario.
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[Inventories of the Earth. Mineral resource appraisals and the rise of resource economics].
Westermann, Andrea
2014-03-01
How do the earth sciences mediate between the natural and social world? This paper explores the question by focusing on the history of nonfuel mineral resource appraisal from the late nineteenth to the mid twentieth century. It argues that earth sciences early on embraced social scientific knowledge, i.e. economic knowledge, in particular, when it came to determining or deposits and estimating the magnitude of mineral reserves. After 1900, assessing national and global mineral reserves and their "life span" or years of supply became ever more important, scaling up and complementing traditional appraisal practices on the level of individual mines or mining and trading companies. As a consequence, economic methods gained new weight for mineral resource estimation. Natural resource economics as an own field of research grew out of these efforts. By way of example, the mineral resource appraisal assigned to the U.S. Materials Policy Commission by President Harry S. Truman in 1951 is analyzed in more detail. Natural resource economics and environmental economics might be interpreted as a strategy to bring down the vast and holistically conceived object of geological and ecological research, the earth, to human scale, and assimilate it into social matters.
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Kaplinger, Brian Douglas
For the past few decades, both the scientific community and the general public have been becoming more aware that the Earth lives in a shooting gallery of small objects. We classify all of these asteroids and comets, known or unknown, that cross Earth's orbit as near-Earth objects (NEOs). A look at our geologic history tells us that NEOs have collided with Earth in the past, and we expect that they will continue to do so. With thousands of known NEOs crossing the orbit of Earth, there has been significant scientific interest in developing the capability to deflect an NEO from an impacting trajectory. This thesis applies the ideas of Smoothed Particle Hydrodynamics (SPH) theory to the NEO disruption problem. A simulation package was designed that allows efficacy simulation to be integrated into the mission planning and design process. This is done by applying ideas in high-performance computing (HPC) on the computer graphics processing unit (GPU). Rather than prove a concept through large standalone simulations on a supercomputer, a highly parallel structure allows for flexible, target dependent questions to be resolved. Built around nonclassified data and analysis, this computer package will allow academic institutions to better tackle the issue of NEO mitigation effectiveness.
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Directory of Open Access Journals (Sweden)
Alessandra Magagna
2012-07-01
Full Text Available During the International Year of Planet Earth (2007-2009, the Department of Earth Sciences of Turin University and a local Museum of Natural History promoted a project entitled, Understanding how the Earth works: from local situations to global processes. In this context, two geothematic exhibitions on the Cape Verde Archipelago were designed and staged in local museums. The exhibition called Getting to know a volcano in order to live with it was the subject of action research that involved the design of interactive activities and the analysis of data collected during guided tours conducted with students of different ages. This study allowed the demonstration of the effectiveness of teaching strategies in which relevant Earth sciences topics are proposed, like risk and sustainable development, thus stimulating debate among the students. This approach enhances the cultural experience of individuals by sharing it with other people. The aim was to widen their awareness of the cultural value of the territory, and to stimulate a new critical way of thinking about the Earth sciences. These didactic tools were further developed when they were proposed and pursued by experienced museum guides and teachers, who were able to involve not only institutions (museums and schools in the knowledge construction process, but also families, relatives and the local community.
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The human dimension of fire regimes on Earth.
Bowman, David M J S; Balch, Jennifer; Artaxo, Paulo; Bond, William J; Cochrane, Mark A; D'Antonio, Carla M; Defries, Ruth; Johnston, Fay H; Keeley, Jon E; Krawchuk, Meg A; Kull, Christian A; Mack, Michelle; Moritz, Max A; Pyne, Stephen; Roos, Christopher I; Scott, Andrew C; Sodhi, Navjot S; Swetnam, Thomas W; Whittaker, Robert
2011-12-01
Humans and their ancestors are unique in being a fire-making species, but 'natural' (i.e. independent of humans) fires have an ancient, geological history on Earth. Natural fires have influenced biological evolution and global biogeochemical cycles, making fire integral to the functioning of some biomes. Globally, debate rages about the impact on ecosystems of prehistoric human-set fires, with views ranging from catastrophic to negligible. Understanding of the diversity of human fire regimes on Earth in the past, present and future remains rudimentary. It remains uncertain how humans have caused a departure from 'natural' background levels that vary with climate change. Available evidence shows that modern humans can increase or decrease background levels of natural fire activity by clearing forests, promoting grazing, dispersing plants, altering ignition patterns and actively suppressing fires, thereby causing substantial ecosystem changes and loss of biodiversity. Some of these contemporary fire regimes cause substantial economic disruptions owing to the destruction of infrastructure, degradation of ecosystem services, loss of life, and smoke-related health effects. These episodic disasters help frame negative public attitudes towards landscape fires, despite the need for burning to sustain some ecosystems. Greenhouse gas-induced warming and changes in the hydrological cycle may increase the occurrence of large, severe fires, with potentially significant feedbacks to the Earth system. Improved understanding of human fire regimes demands: (1) better data on past and current human influences on fire regimes to enable global comparative analyses, (2) a greater understanding of different cultural traditions of landscape burning and their positive and negative social, economic and ecological effects, and (3) more realistic representations of anthropogenic fire in global vegetation and climate change models. We provide an historical framework to promote understanding
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The human dimension of fire regimes on Earth
Bowman, David M.J.S.; Balch, Jennifer; Artaxo, Paulo; Bond, William J.; Cochrane, Mark A.; D'Antonio, Carla M.; DeFries, Ruth; Johnston, Fay H.; Keeley, Jon E.; Krawchuk, Meg A.; Kull, Christian A.; Michelle, Mack; Moritz, Max A.; Pyne, Stephen; Roos, Christopher I.; Scott, Andrew C.; Sodhi, Navjot S.; Swetnam, Thomas W.
2011-01-01
Humans and their ancestors are unique in being a fire-making species, but 'natural' (i.e. independent of humans) fires have an ancient, geological history on Earth. Natural fires have influenced biological evolution and global biogeochemical cycles, making fire integral to the functioning of some biomes. Globally, debate rages about the impact on ecosystems of prehistoric human-set fires, with views ranging from catastrophic to negligible. Understanding of the diversity of human fire regimes on Earth in the past, present and future remains rudimentary. It remains uncertain how humans have caused a departure from 'natural' background levels that vary with climate change. Available evidence shows that modern humans can increase or decrease background levels of natural fire activity by clearing forests, promoting grazing, dispersing plants, altering ignition patterns and actively suppressing fires, thereby causing substantial ecosystem changes and loss of biodiversity. Some of these contemporary fire regimes cause substantial economic disruptions owing to the destruction of infrastructure, degradation of ecosystem services, loss of life, and smoke-related health effects. These episodic disasters help frame negative public attitudes towards landscape fires, despite the need for burning to sustain some ecosystems. Greenhouse gas-induced warming and changes in the hydrological cycle may increase the occurrence of large, severe fires, with potentially significant feedbacks to the Earth system. Improved understanding of human fire regimes demands: (1) better data on past and current human influences on fire regimes to enable global comparative analyses, (2) a greater understanding of different cultural traditions of landscape burning and their positive and negative social, economic and ecological effects, and (3) more realistic representations of anthropogenic fire in global vegetation and climate change models. We provide an historical framework to promote understanding
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Directory of Open Access Journals (Sweden)
Chinami Matsumoto
2008-01-01
Full Text Available ‘Oketsu’ is a pathophysiologic concept in Japanese traditional (Kampo medicine, primarily denoting blood stasis/stagnant syndrome. Here we have explored plasma protein biomarkers and/or diagnostic algorithms for ‘Oketsu’. Sixteen rheumatoid arthritis (RA patients were treated with keishibukuryogan (KBG, a representative Kampo medicine for improving ‘Oketsu’. Plasma samples were diagnosed as either having an ‘Oketsu’ (n = 19 or ‘non-Oketsu’ (n = 29 state according to Terasawa's ‘Oketsu’ scoring system. Protein profiles were obtained by surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS and hierarchical clustering and decision tree analyses were performed. KBG treatment for 4 or 12 weeks decreased the ‘Oketsu’ scores significantly. SELDI protein profiles gave 266 protein peaks, whose expression was significantly different between the ‘Oketsu’ and ‘non-Oketsu’ states. Hierarchical clustering gave three major clusters (I, II, III. The majority (68.4% of ‘Oketsu’ samples were clustered into one cluster as the principal component of cluster I. The remaining ‘Oketsu’ profiles constituted a minor component of cluster II and were all derived from patients cured of the ‘Oketsu’ state at 12 weeks. Construction of the decision tree addressed the possibility of developing a diagnostic algorithm for ‘Oketsu’. A reduction in measurement/pre-processing conditions (from 55 to 16 gave a similar outcome in the clustering and decision tree analyses. The present study suggests that the pathophysiologic concept of Kampo medicine ‘Oketsu’ has a physical basis in terms of the profile of blood proteins. It may be possible to establish a set of objective criteria for diagnosing ‘Oketsu’ using a combination of proteomic and bioinformatics-based classification methods.
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Towards Big Earth Data Analytics: The EarthServer Approach
Baumann, Peter
2013-04-01
Big Data in the Earth sciences, the Tera- to Exabyte archives, mostly are made up from coverage data whereby the term "coverage", according to ISO and OGC, is defined as the digital representation of some space-time varying phenomenon. Common examples include 1-D sensor timeseries, 2-D remote sensing imagery, 3D x/y/t image timeseries and x/y/z geology data, and 4-D x/y/z/t atmosphere and ocean data. Analytics on such data requires on-demand processing of sometimes significant complexity, such as getting the Fourier transform of satellite images. As network bandwidth limits prohibit transfer of such Big Data it is indispensable to devise protocols allowing clients to task flexible and fast processing on the server. The EarthServer initiative, funded by EU FP7 eInfrastructures, unites 11 partners from computer and earth sciences to establish Big Earth Data Analytics. One key ingredient is flexibility for users to ask what they want, not impeded and complicated by system internals. The EarthServer answer to this is to use high-level query languages; these have proven tremendously successful on tabular and XML data, and we extend them with a central geo data structure, multi-dimensional arrays. A second key ingredient is scalability. Without any doubt, scalability ultimately can only be achieved through parallelization. In the past, parallelizing code has been done at compile time and usually with manual intervention. The EarthServer approach is to perform a samentic-based dynamic distribution of queries fragments based on networks optimization and further criteria. The EarthServer platform is comprised by rasdaman, an Array DBMS enabling efficient storage and retrieval of any-size, any-type multi-dimensional raster data. In the project, rasdaman is being extended with several functionality and scalability features, including: support for irregular grids and general meshes; in-situ retrieval (evaluation of database queries on existing archive structures, avoiding data
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2009-07-01
WE RECOMMEND Doctor Atomic The new Doctor Atomic opera provkes discussion on ethics I Cyborg The world's first human cyborg shares his life story in I Cyborg Flat Earth: The History of an Infamous Idea Flat Earth gives us a different perspective on creationism Mere Thermodynamics An introductory text on the three laws CGP revision guides This revision guide suits all courses and every pocket Hiding the Elephant: How Magicians Invented the Impossible The mystery of many illusions are solved in this book Back of the Envelope Physics This reference deserves a place on your bookshelf WORTH A LOOK Doctor Atomic The DVD doesn't do justice to the live performance Digital stopclock with external trigger Use these stopclocks when you need an external trigger WEB WATCH Webcasts reach out to an online audience
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Calcium Isotopic Composition of Bulk Silicate Earth
Kang, J.; Ionov, D. A.; Liu, F.; Zhang, C.; Zhang, Z.; Huang, F.
2016-12-01
Ca isotopes are used to study the accretion history of the Earth and terrestrial planets, but, Ca isotopic composition of the Bulk Silicate Earth (BSE) remains poorly constrained [1]. To better understand the Ca isotopic composition of BSE, we analyzed 22 well studied peridotite xenoliths from Tariat (Mongolia), Vitim (southern Siberia) and Udachnaya (Siberian Craton). These samples include both fertile and highly depleted garnet and spinel peridotites that show no or only minor post-melting metasomatism or alteration. Ca isotope measurements were done on a Triton-TIMS using double spike method at the Guangzhou Institute of Geochemistry, CAS. The data are reported as δ44/40Ca (relative to NIST SRM 915a). Results for geostandards are consistent with those from other laboratories. 2 standard deviations of SRM 915a analyses are 0.13‰ (n=48). δ44/40Ca of both and fertile and refractory peridotites range from 0.79 to 1.07‰ producing an average of 0.93±0.12‰ (2SD). This value defines the Ca isotopic composition of the BSE, which is consistent with the average δ44/40Ca of oceanic basalts ( 0.90‰)[2,3]. [1] Huang et al (2010) EPSL 292; [2] Valdes et al (2014) EPSL 394; [3]DePaolo (2004) RMG 55.
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Mogk, D. W.; Schmitt, J.
2013-12-01
The Dept. of Earth Sciences, Montana State University, recently completed a comprehensive revision of its undergraduate curriculum to meet challenges and opportunities in training the next generation geoscience workforce. The department has 280 undergraduate majors in degree options that include: geology, geography (physical and human), snow science, paleontology and GIS/planning. We used a 'backward design' approach by first considering the profile of a student leaving our program: what should they know and be able to do, in anticipation of professional development for traditional (exploration, environmental, regulatory agencies) and non-traditional (planning, policy, law, business, teaching) jobs or for further training in graduate school. We adopted an Earth system approach to be better aligned with contemporary approaches to Earth science and to demonstrate the connections between sub-disciplines across the curriculum. Learning sequences were designed according to Bloom's Taxonomy to develop higher level thinking skills (starting from observations and progressing to descriptions, interpretations, applications, integration of multiple lines of evidence, synthetic and analytical thinking and evaluation). Central themes are reinforced in multiple classes: history and evolution of the Earth system, composition and architecture of Earth, surface of Earth and the 'critical zone' and human dimensions. The cornerstones of the curriculum are strong background in cognate sciences, geologic 'habits of mind', an emphasis on geologic processes and field instruction. Ancillary learning goals include development of quantitative, communication, and interpersonal skills; use of Earth data and modeling; systems thinking; research and research-like experiences; and applications to societal issues. The first year course of study includes a slate of courses to explore the Earth system, primarily to engage and recruit students to the major. Second year studies are foundational for
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History or histories of socio-economic rights?
DEFF Research Database (Denmark)
Christiansen, Christian O.
2016-01-01
The German historian Reinhart Koselleck was once described as a partisan for histories in the plural (as opposed to history in the singular). His point was that history has many different layers, logics, and temporalities and that the modernist idea of one, overarching history with one direction ......) at work in the histories and dynamics of socio-economic rights. More specifically, I propose a list of eight important variables that may help explain the dynamics of the histories of socio-economic rights - their failures as well as their successes....... (telos) – be it towards progress or decline – was inadequate for the multi-faceted geographies, rhythms and dynamics of life. In these reflections on a two-days research workshop in Paris, I argue that Koselleck’s point also applies to the field of the history of socio-economic rights. Instead of writing...... the history of socio-economic rights, I would propose thinking about the histories of socio-economic rights. There are three main reasons for this: the non-teleological histories of socioeconomic rights; the distinctiveness between different socio-economic rights; and the complexity (multiple variables...
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Carter, Jason
2017-01-01
This curriculum-based, easy-to-follow book teaches young readers about Earth as one of the eight planets in our solar system in astronomical terms. With accessible text, it provides the fundamental information any student needs to begin their studies in astronomy, such as how Earth spins and revolves around the Sun, why it's uniquely suitable for life, its physical features, atmosphere, biosphere, moon, its past, future, and more. To enhance the learning experience, many of the images come directly from NASA. This straightforward title offers the fundamental information any student needs to sp
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Rare earths in uranium compounds and important evidences for nuclear forensic purposes
International Nuclear Information System (INIS)
Rosa, Daniele S.; Sarkis, Jorge E.S.
2011-01-01
Nuclear forensics mainly focuses on the nuclear or radioactive material and aims to providing indication on the intended use, the history and even the origin of the material. Uranium compounds have isotopic or chemical characteristics that provide unambiguous information concerning their origin and production process. Rare earths elements (REE) are a set of sixteen chemical elements in the periodic table, specifically the fourteen Lanthanides in addition scandium and yttrium. These elements are often found together but in widely variable concentrations in uncommon varieties of igneous rocks. A large amount of uranium is in rare earths deposits, and may be extracted as a by-product. Accordingly, REE in uranium compounds can be used as an evidence of uranium origin. In this study, REE was determined in uranium compounds from different origin. Measurements were carried out using a High resolution inductively coupled plasma mass spectrometer (HR-ICP-MS) Element 2, in low resolution mode (R-300). (author)
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Bedrock Canyons Carved by the Largest Known Floods on Earth and Mars
Lamb, M. P.; Lapôtre, M. G. A.; Larsen, I. J.; Williams, R. M. E.
2017-12-01
The surface of Earth is a dynamic and permeable interface where the rocky crust is sculpted by ice, wind and water resulting in spectacular mountain ranges, vast depositional basins and environments that support life. These landforms and deposits contain a rich, yet incomplete, record of Earth history that we are just beginning to understand. Some of the most dramatic landforms are the huge bedrock canyons carved by catastrophic floods. On Mars, similar bedrock canyons, known as Outflow Channels, are the most important indicators of large volumes of surface water in the past. Despite their importance and now decades of observations of canyon morphology, we lack a basic understanding of how the canyons formed, which limits our ability to reconstruct flood discharge, duration and water volume. In this presentation I will summarize recent work - using mechanistic numerical models and field observations - that suggests that bedrock canyons carved by megafloods rapidly evolve to a size and shape such that boundary shear stresses just exceed that required to entrain fractured blocks of rock. The threshold shear stress constraint allows for quantitative reconstruction of the largest known floods on Earth and Mars, and implies far smaller discharges than previous methods that assume flood waters fully filled the canyons to high water marks.
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Earth Science Outreach: A Move in the Right Direction
McLarty Halfkenny, B.; Schröder Adams, C.
2009-05-01
science and global issues such as climate science and stewardship of our natural resources. A new initiative for Science and Technology Week, 'Explore Geoheritage Day' introduced the public to the geological history of the National Capital Region. We have found collaborations with other agencies very effective. We work with PDAC's "Mining Matters", LTS, the Ottawa Gatineau Geoheritage Project, Ottawa Heritage, STAO, local school boards, naturalist groups, and other community organizations to promote Earth Science education. Our efforts over the last 5 years have brought tangible results in: a) a considerable increase in student enrolment at the university level in our department; b) increased teaching of the Grade 12 Earth and Space Sciences course at local high schools through teachers who were inspired by our workshops; c) a flourishing network of enthusiastic earth science educators sharing ideas with us to define each other's needs; and d) a growing interaction with the general public. Future initiatives need to consider lobbying for curriculum changes to give Earth Science a prominent place in the public education system. As well, only few university education departments currently allow Earth Science graduates into their programs, requiring them to first take additional courses in other "teachable" subjects. This must change. University graduates with an Earth Science degree and an interest in teaching must be permitted direct entry into these programs so that their skills will be passed on to the next generation of science students.
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Pechernikova, G. V.; Ruskol, E. L.
2017-05-01
An analytical review of the two contemporary models of the origin of the Earth-Moon system in the process of solid-body accretion is presented: socalled co-accretion model and as a result of a gigantic collision with a planetarysized body (i.e. a megaimpact model). The co-accretion model may be considered as a universal mechanism of the origin of planetary satellites, that accompanies the growth of planets. We consider the conditions of this process that secure the sufficient mass and angular momentum of the protolunar disk such as macroimpacts (collisions with the bodies of asteroidal size) into the mantle of the growing Earth, the role of an lunar embryo growing on the geocentric lunar orbit, its tidal interaction with the Earth. The most difficult remains the explanation of chemical composition of the Moon. Different scenarios of megaimpact are reviewed, in which the Earth's mantle is destroyed and the protosatellite disk is filled mainly by its fragments. There is evaluated amount of energy transferred to the Earth from the evolution of lunar orbit. It is an order of magnitude lower than three main sources of the Earth's interior heat, i.e. the heat of accretion, the energy of differentiation and the heat of radioactive sources. The tidal heating of the Venus's interiors could reach 1000K by slowing its axial initial rotation, in addition to three sources mentioned above in concern of the Earth.
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Influence of slip-surface geometry on earth-flow deformation, Montaguto earth flow, southern Italy
Guerriero, L.; Coe, Jeffrey A.; Revellio, P.; Grelle, G.; Pinto, F.; Guadagno, F.
2016-01-01
We investigated relations between slip-surface geometry and deformational structures and hydrologic features at the Montaguto earth flow in southern Italy between 1954 and 2010. We used 25 boreholes, 15 static cone-penetration tests, and 22 shallow-seismic profiles to define the geometry of basal- and lateral-slip surfaces; and 9 multitemporal maps to quantify the spatial and temporal distribution of normal faults, thrust faults, back-tilted surfaces, strike-slip faults, flank ridges, folds, ponds, and springs. We infer that the slip surface is a repeating series of steeply sloping surfaces (risers) and gently sloping surfaces (treads). Stretching of earth-flow material created normal faults at risers, and shortening of earth-flow material created thrust faults, back-tilted surfaces, and ponds at treads. Individual pairs of risers and treads formed quasi-discrete kinematic zones within the earth flow that operated in unison to transmit pulses of sediment along the length of the flow. The locations of strike-slip faults, flank ridges, and folds were not controlled by basal-slip surface topography but were instead dependent on earth-flow volume and lateral changes in the direction of the earth-flow travel path. The earth-flow travel path was strongly influenced by inactive earth-flow deposits and pre-earth-flow drainages whose positions were determined by tectonic structures. The implications of our results that may be applicable to other earth flows are that structures with strikes normal to the direction of earth-flow motion (e.g., normal faults and thrust faults) can be used as a guide to the geometry of basal-slip surfaces, but that depths to the slip surface (i.e., the thickness of an earth flow) will vary as sediment pulses are transmitted through a flow.
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Boyet, M.; Bouvier, A.; Frossard, P.; Hammouda, T.; Garçon, M.; Gannoun, A.
2018-04-01
analyzed for Mo isotopes. Because these enstatite chondrites are relatively small in size and number, they are usually not available for destructive isotopic measurements. Average values based on the measurement of EL6 samples should not be considered as representative of the whole EL group because of melting and thermal metamorphism events affecting the Sm/Nd ratios and prolonged open-system history. The EL3 chondrites are the best candidates as the Earth's building blocks. These new results remove the need to change the composition of refractory incompatible elements early in Earth's history.
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International Nuclear Information System (INIS)
Hidaka, Hiroshi; Sakuma, Keisuke; Nishiizumi, Kunihiko; Yoneda, Shigekazu
2017-01-01
It is known that most lunar meteorites have complicated cosmic-ray exposure experiences on the Moon and in space. In this study, cosmic-ray irradiation histories of six lunar meteorites, Dhofar 489, Northwest Africa 032 (NWA 032), NWA 479, NWA 482, NWA 2995, and NWA 5000, were characterized from neutron-captured isotopic shifts of Sm and Gd, and from the abundances of long-lived cosmogenic radionuclides like 10 Be, 26 Al, 36 Cl, and 41 Ca. Sm and Gd isotopic data of all of six meteorites show significant isotopic shifts of 149 Sm– 150 Sm and 157 Gd– 158 Gd caused by accumulation of neutron capture reactions due to cosmic-ray irradiation, corresponding to the neutron fluences of (1.3–9.6) × 10 16 n cm −2 . In particular, very large Sm and Gd isotopic shifts of NWA 482 are over those of a lunar regolith 70002, having the largest isotopic shifts among the Apollo regolith samples, corresponding to cosmic-ray exposure duration over 800 million years in the lunar surface (2 π irradiation). Meanwhile, the concentrations of cosmogenic radionuclides for individual six meteorites show the short irradiation time less than one million years as their bodies in space (4 π irradiation). Our data also support the results of previous studies, revealing that most of lunar meteorites have long exposure ages at shallow depths on the Moon and short transit times from the Moon to the Earth.
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Rare earth octacyanomolybdates(4)
International Nuclear Information System (INIS)
Zubritskaya, D.I.; Sergeeva, A.N.; Pisak, Yu.V.
1980-01-01
Optimal conditions for synthesis of rare-earth octacyanomolybdates(4) of the Ln 4 [Mo(CN) 8 ] 3 xnH 2 O composition (where Ln is a rare-earth element, other than Pr, Pm, Lu, Tb) have been worked out. The synthesis has been accomplished by neutralization with octacianomolybdic acid with rare-earth carbonates. The composition and structure of the compounds synthesized have been studied by infrared-spectroscopy. It has been established that rare-earth octacyanomolybdates(4) form three isostructural groups
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Rare earths as a future resource
International Nuclear Information System (INIS)
Cornell, D.H.
1988-01-01
The fourteen rare earth or lanthanide elements have recently emerged as an important natural resource because of the rapidly growing demand in the electronic, chemical and metallurgical industries. The Symposium on rare earth elements as a future resource presented a multidisciplinary review of rare earth chemistry, geology, beneficiation, industrial applications and marketing. Papers by experts in many fields were presented on the following topics: chemical properties of the rare earth elements; the analysis of rare earth elements and minerals; beneficiation and extraction of rare earth elements; economic geochemistry and mineralogy of rare earths; present industrial uses of rare earth elements; the role of rare earth elements in high-temperature superconductors; the technical application of high-temperature superconductors; supply and demand for rare earth products - now and in the future, and the geology of rare earth deposits
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Gao, Xun; Mu, Jingqing; Guan, Shaoyi; Li, Qing; Du, Yiyang; Zhang, Huifen; Bi, Kaishun
2018-01-01
Guan-Xin-Shu-Tong capsules are one of the well-known and first-line Chinese traditional herbal formula for treating coronary heart disease. A validated and sensitive method via ultra fast liquid chromatography-tandem mass spectrometry (UFLC-MS/MS) was established to simultaneously determinate five phenolic acids and four diterpenoids in rats in order to investigate their pharmacokinetic profiles firstly. Analytes were extracted by ethyl acetate and determined via multiple reaction monitoring mode in both positive and negative ion modes. The values for limit of quantification were in range of 0.025-1.250ng/ml. Inter- and intra-day precisions were no more than 10.9% with accuracy of -11.0%-10.6%, meanwhile the stable and suitable extraction recoveries were also obtained. And finally such excellent method was used to compare the pharmacokinetics of nine compounds in normal and acute blood stasis rats after oral administration of Guan-Xin-Shu-Tong capsules. Copyright © 2017 Elsevier B.V. All rights reserved.
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Earthing: Health Implications of Reconnecting the Human Body to the Earth's Surface Electrons
International Nuclear Information System (INIS)
Chevalier, G.; Chevalier, G.; Sinatra, S.T.; Oschman, J.L.; Sokal, K.; Sokal, P.
2012-01-01
Environmental medicine generally addresses environmental factors with a negative impact on human health. However, emerging scientific research has revealed a surprisingly positive and overlooked environmental factor on health: direct physical contact with the vast supply of electrons on the surface of the Earth. Modern lifestyle separates humans from such contact. The research suggests that this disconnect may be a major contributor to physiological dysfunction and un wellness. Reconnection with the Earth's electrons has been found to promote intriguing physiological changes and subjective reports of well-being. Earthing (or grounding) refers to the discovery of benefits including better sleep and reduced pain from walking barefoot outside or sitting, working, or sleeping indoors connected to conductive systems that transfer the Earth's electrons from the ground into the body. This paper reviews the earthing research and the potential of earthing as a simple and easily accessed global modality of significant clinical importance
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Next-generation Digital Earth.
Goodchild, Michael F; Guo, Huadong; Annoni, Alessandro; Bian, Ling; de Bie, Kees; Campbell, Frederick; Craglia, Max; Ehlers, Manfred; van Genderen, John; Jackson, Davina; Lewis, Anthony J; Pesaresi, Martino; Remetey-Fülöpp, Gábor; Simpson, Richard; Skidmore, Andrew; Wang, Changlin; Woodgate, Peter
2012-07-10
A speech of then-Vice President Al Gore in 1998 created a vision for a Digital Earth, and played a role in stimulating the development of a first generation of virtual globes, typified by Google Earth, that achieved many but not all the elements of this vision. The technical achievements of Google Earth, and the functionality of this first generation of virtual globes, are reviewed against the Gore vision. Meanwhile, developments in technology continue, the era of "big data" has arrived, the general public is more and more engaged with technology through citizen science and crowd-sourcing, and advances have been made in our scientific understanding of the Earth system. However, although Google Earth stimulated progress in communicating the results of science, there continue to be substantial barriers in the public's access to science. All these factors prompt a reexamination of the initial vision of Digital Earth, and a discussion of the major elements that should be part of a next generation.
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Disequilibrium biosignatures over Earth history and implications for detecting exoplanet life
Krissansen-Totton, Joshua; Olson, Stephanie; Catling, David C.
2018-01-01
Chemical disequilibrium in planetary atmospheres has been proposed as a generalized method for detecting life on exoplanets through remote spectroscopy. Among solar system planets with substantial atmospheres, the modern Earth has the largest thermodynamic chemical disequilibrium due to the presence of life. However, how this disequilibrium changed over time and, in particular, the biogenic disequilibria maintained in the anoxic Archean or less oxic Proterozoic eons are unknown. We calculate the atmosphere-ocean disequilibrium in the Precambrian using conservative proxy- and model-based estimates of early atmospheric and oceanic compositions. We omit crustal solids because subsurface composition is not detectable on exoplanets, unlike above-surface volatiles. We find that (i) disequilibrium increased through time in step with the rise of oxygen; (ii) both the Proterozoic and Phanerozoic may have had remotely detectable biogenic disequilibria due to the coexistence of O2, N2, and liquid water; and (iii) the Archean had a biogenic disequilibrium caused by the coexistence of N2, CH4, CO2, and liquid water, which, for an exoplanet twin, may be remotely detectable. On the basis of this disequilibrium, we argue that the simultaneous detection of abundant CH4 and CO2 in a habitable exoplanet’s atmosphere is a potential biosignature. Specifically, we show that methane mixing ratios greater than 10−3 are potentially biogenic, whereas those exceeding 10−2 are likely biogenic due to the difficulty in maintaining large abiotic methane fluxes to support high methane levels in anoxic atmospheres. Biogenicity would be strengthened by the absence of abundant CO, which should not coexist in a biological scenario. PMID:29387792
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Hide, Raymond; Dickey, Jean O.
1991-01-01
Recent improvements in geodetic data and practical meteorology have advanced research on fluctuations in the earth's rotation. The interpretation of these fluctuations is inextricably linked with studies of the dynamics of the earth-moon system and dynamical processes in the liquid metallic core of the earth (where the geomagnetic field originates), other parts of the earth's interior, and the hydrosphere and atmosphere. Fluctuations in the length of the day occurring on decadal time scales have implications for the topographay of the core-mantle boundary and the electrical, magnetic, ande other properties of the core and lower mantle. Investigations of more rapid fluctuations bear on meteorological studies of interannual, seasonal, and intraseasonal variations in the general circulation of the atmosphere and the response of the oceans to such variations.
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Sustainability, collapse and oscillations in a simple World-Earth model
Nitzbon, Jan; Heitzig, Jobst; Parlitz, Ulrich
2017-07-01
The Anthropocene is characterized by close interdependencies between the natural Earth system and the global human society, posing novel challenges to model development. Here we present a conceptual model describing the long-term co-evolution of natural and socio-economic subsystems of Earth. While the climate is represented via a global carbon cycle, we use economic concepts to model socio-metabolic flows of biomass and fossil fuels between nature and society. A well-being-dependent parametrization of fertility and mortality governs human population dynamics. Our analysis focuses on assessing possible asymptotic states of the Earth system for a qualitative understanding of its complex dynamics rather than quantitative predictions. Low dimension and simple equations enable a parameter-space analysis allowing us to identify preconditions of several asymptotic states and hence fates of humanity and planet. These include a sustainable co-evolution of nature and society, a global collapse and everlasting oscillations. We consider different scenarios corresponding to different socio-cultural stages of human history. The necessity of accounting for the ‘human factor’ in Earth system models is highlighted by the finding that carbon stocks during the past centuries evolved opposing to what would ‘naturally’ be expected on a planet without humans. The intensity of biomass use and the contribution of ecosystem services to human well-being are found to be crucial determinants of the asymptotic state in a (pre-industrial) biomass-only scenario without capital accumulation. The capitalistic, fossil-based scenario reveals that trajectories with fundamentally different asymptotic states might still be almost indistinguishable during even a centuries-long transient phase. Given current human population levels, our study also supports the claim that besides reducing the global demand for energy, only the extensive use of renewable energies may pave the way into a
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Obliquity histories of Earth and Mars: Influence of inertial and dissipative core-mantle coupling
Bills, Bruce G.
1990-01-01
For both the Earth and Mars, secular variations in the angular separation of the spin axis from the orbit normal are suspected of driving major climatic changes. There is considerable interest in determining the amplitude and timing of these obliquity variations. If the orientation of the orbital plane were inertially fixed, and the planet were to act as a rigid body in it response to precessional torques, the spin axis would simply precess around the orbit at a fixed obliquity and at a uniform angular rate. The precession rate parameter depends on the principal moments of inertia and rotation rate of the perturbed body, and on the gravitational masses and semiminor axes of the perturbing bodies. For Mars, the precession rate is not well known, but probably lies in the interval 8 to 10 arcsec/year. Gravitational interactions between the planets lead to secular motions of the orbit planes. In the rigid body case, the spin axis still attempts to precess about the instantaneous orbit normal, but now the obliquity varies. The hydrostatic figure of a planet represents a compromise between gravitation, which attempts to attain spherical symmetry, and rotation, which prefers cylindrical symmetry. Due to their higher mean densities the cores of the Earth and Mars will be more nearly spherical than the outer layers of these planets. On short time scales it is appropriate to consider the core to be an inviscid fluid constrained to move with the ellipsoidal region bounded by the rigid mantle. The inertial coupling provided by this mechanism is effective whenever the ellipticicy of the container exceeds the ratio of precessional to rotational rates. If the mantle were actually rigid, this would be an extremely effective type of coupling. However, on sufficiently long time scales, the mantle will deform viscously and can accommodate the motions of the core fluid. A fundamentally different type of coupling is provided by electromagnetic or viscous torques. This type of coupling
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Online Astronomy Resources from the American Museum of Natural History
Steiner, Robert
2010-02-01
The American Museum of Natural History, one of the world's largest natural history museums, is the locus of a rich array of scientific research, exhibition and educational resources through its Department of Astrophysics, its Rose Center for Earth and Space and its Hall of Meteorites. For the past decade, the Museum's National Center for Science Literacy, Education and Technology has leveraged these assets to create a panoply of web-based resources for students, teachers and the general public. This session will review several of these resources, including the Digital Universe (a three-dimensional mapping of the Universe); The Solar System (an online graduate course for K-12 teachers); multimedia highlighting searches for exoplanets and ultra-high-energy cosmic rays; Journey to the Stars (a DVD version of the current planetarium show); and the astronomy section of Ology (a website for children ages 7 and up). A copy of the Journey to the Stars DVD will be provided to all attendees. )
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Stixrude, Lars
2014-04-28
We examine the possible extent of melting in rock-iron super-earths, focusing on those in the habitable zone. We consider the energetics of accretion and core formation, the timescale of cooling and its dependence on viscosity and partial melting, thermal regulation via the temperature dependence of viscosity, and the melting curves of rock and iron components at the ultra-high pressures characteristic of super-earths. We find that the efficiency of kinetic energy deposition during accretion increases with planetary mass; considering the likely role of giant impacts and core formation, we find that super-earths probably complete their accretionary phase in an entirely molten state. Considerations of thermal regulation lead us to propose model temperature profiles of super-earths that are controlled by silicate melting. We estimate melting curves of iron and rock components up to the extreme pressures characteristic of super-earth interiors based on existing experimental and ab initio results and scaling laws. We construct super-earth thermal models by solving the equations of mass conservation and hydrostatic equilibrium, together with equations of state of rock and iron components. We set the potential temperature at the core-mantle boundary and at the surface to the local silicate melting temperature. We find that ancient (∼4 Gyr) super-earths may be partially molten at the top and bottom of their mantles, and that mantle convection is sufficiently vigorous to sustain dynamo action over the whole range of super-earth masses.
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Holt, Geoff
2011-01-01
Project Earth Science: Astronomy, Revised 2nd Edition, involves students in activities that focus on Earth's position in our solar system. How do we measure astronomical distances? How can we look back in time as we gaze across vast distances in space? How would our planet be different without its particular atmosphere and distance to our star? What are the geometries among Earth, the Moon, and the Sun that yield lunar phases and seasons? Students explore these concepts and others in 11 teacher-tested activities.
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Studies with the EC-Earth seamless Earth system prediction model
Hazeleger, W.; Bintanja, R.
2012-01-01
EC-Earth is a new Earth System Model (ESM) based on the operational seasonal forecast system of the European Centre for Medium-Range Weather Forecasts (ECMWF). Climate and weather forecasting applications share a common ancestry and are build on the same physical principles. The emerging concept of
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Geomorphosites and the history of geomorphology
Giusti, Christian
2013-04-01
Geomorphosites are geosites of geomorphological significance, with a now well admitted distinction between central or scientific values on the one hand, and additional values such as ecological, economical or aesthetical values on the other hand. Among the scientific values, some are directly linked to the climatic forcings through geomorphological processes in the case of active geomorphosites, for example the meaning of a waterfall in a post-glacial trough valley. In the case of passive geomorphosites, the central values rather lie in structural features, ancient landforms, inherited regoliths such as the clay-with-flints of the Chalklands of Southern England and Northern France. Sometimes, the scientific value is not fully determined by the type of geomorphosite, active or passive, but rather by the fact this geosite has a special importance concerning the history of the Earth sciences, especially in geomorphology. This is well exemplified with the famous case of the Nant d'Arpenaz waterfall S-folds in the lower Arve valley between Geneva and Chamonix, first described by Horace Benedict de Saussure in 1774 and invoked to explain the formation of the Alps by folding. This structural geosite (history of tectonics) is also a geomorphosite. Concerning geomorphology, the current Nant d'Arpenaz waterfall is quite similar to the Pissevache waterfall in the Rhone valley: they are both examples of postglacial geomorphosites due to hanging valleys. When erosion is more advanced narrow gorges appear, for example Diosaz gorge (Haute-Savoie, France) or Dailley, Trient and Triège gorges (Valais, Switzerland). All these geomorphosites (main trough valleys, tributary valleys, waterfalls and postglacial gorges) were studied by pionneers of fluvial and glacial geomorphology such as Jean Bruhnes and Emmanuel de Martonne before World War I. The former has played an important role at the University of Fribourg (Switzerland) and has devoted many studies about the potholes and eddies
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Components for Maintaining and Publishing Earth Science Vocabularies
Cox, S. J. D.; Yu, J.
2014-12-01
Shared vocabularies are an important aid to geoscience data interoperability. Many organizations maintain useful vocabularies, with Geologic Surveys having a particularly long history of vocabulary and lexicon development. However, the mode of publication is heterogeneous, ranging from PDFs and HTML web pages, spreadsheets and CSV, through various user-interfaces and APIs. Update and maintenance ranges from tightly-governed and externally opaque, through various community processes, all the way to crowd-sourcing ('folksonomies'). A general expectation, however, is for greater harmonization and vocabulary re-use. In order to be successful this requires (a) standardized content formalization and APIs (b) transparent content maintenance and versioning. We have been trialling a combination of software dealing with registration, search and linking. SKOS is designed for formalizing multi-lingual, hierarchical vocabularies, and has been widely adopted in earth and environmental sciences. SKOS is an RDF vocabulary, for which SPARQL is the standard low-level API. However, for interoperability between SKOS vocabulary sources, a SKOS-based API (i.e. based on the SKOS predicates prefLabel, broader, narrower, etc) is required. We have developed SISSvoc for this purpose, and used it to deploy a number of vocabularies on behalf of the IUGS, ICS, NERC, OGC, the Australian Government, and CSIRO projects. SISSvoc Search provides simple search UI on top of one or more SISSvoc sources. Content maintenance is composed of many elements, including content-formalization, definition-update, and mappings to related vocabularies. Typically there is a degree of expert judgement required. In order to provide confidence in users, two requirements are paramount: (i) once published, a URI that denotes a vocabulary item must remain dereferenceable; (ii) the history and status of the content denoted by a URI must be available. These requirements match the standard 'registration' paradigm which is
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Rampino, M. R.
1994-01-01
The theory that large-body impacts are the primary cause of mass extinctions of life on the Earth now has a sound theoretical and observational foundation. A convergence of evidence suggests that the biosphere may be a sensitive detector of large impact events, which result in the recorded global mass extinction pulses. The astronomically observed flux of asteroids and comets in the neighborhood of the Earth, and the threshold impact size calculated to produce a global environment catastrophe, can be used to predict a time history of large impact events and related mass extinctions of life that agrees well with the record of approx. 24 extinction events in the last 540 m.y.
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Earth Science Informatics - Overview
Ramapriyan, H. K.
2017-01-01
Over the last 10-15 years, significant advances have been made in information management, there are an increasing number of individuals entering the field of information management as it applies to Geoscience and Remote Sensing data, and the field of informatics has come to its own. Informatics is the science and technology of applying computers and computational methods to the systematic analysis, management, interchange, and representation of science data, information, and knowledge. Informatics also includes the use of computers and computational methods to support decision making and applications. Earth Science Informatics (ESI, a.k.a. geoinformatics) is the application of informatics in the Earth science domain. ESI is a rapidly developing discipline integrating computer science, information science, and Earth science. Major national and international research and infrastructure projects in ESI have been carried out or are on-going. Notable among these are: the Global Earth Observation System of Systems (GEOSS), the European Commissions INSPIRE, the U.S. NSDI and Geospatial One-Stop, the NASA EOSDIS, and the NSF DataONE, EarthCube and Cyberinfrastructure for Geoinformatics. More than 18 departments and agencies in the U.S. federal government have been active in Earth science informatics. All major space agencies in the world, have been involved in ESI research and application activities. In the United States, the Federation of Earth Science Information Partners (ESIP), whose membership includes over 180 organizations (government, academic and commercial) dedicated to managing, delivering and applying Earth science data, has been working on many ESI topics since 1998. The Committee on Earth Observation Satellites (CEOS)s Working Group on Information Systems and Services (WGISS) has been actively coordinating the ESI activities among the space agencies.The talk will present an overview of current efforts in ESI, the role members of IEEE GRSS play, and discuss
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The International Year of Planet Earth (2007-2009):Earth Sciences for Society
Institute of Scientific and Technical Information of China (English)
Eduardo F.J.de Mulder; Ted Nield; Edward Derbyshire
2006-01-01
Natural disasters like the 2004 tsunami bear graphic testimony to the Earth's incredible power. More effective use of geoscientific knowledge can save lives and protect property. Such knowledge also enables us to satisfy, in a sustainable manner,the growing need for Earth's resources by an expanding human population. Such knowledge is readily available in the practical experience and publications of some half a million Earth scientists all over the world, a professional community that is ready and willing to contribute to a safer, healthier and wealthier society if called upon by politicians and decision makers. Professional guidance by Earth scientists is available in many aspects of everyday life including, for example, identification of the best areas for urban expansion, sites to avoid for waste disposal, the location of new underground fresh water resources, and where certain toxic agents implicated in Earth-related diseases may be located, etc.The International Year of Planet Earth (2007-2009) aims to build on existing knowledge and make it more available for the improvement of everyday life, especially in the less developed countries, as expressed in the Year's subtitle: Earth sciences for Society. Ambitious outreach and science programmes constitute the backbone of the International Year, now politically endorsed by all 191 member states of the United Nations Organisation which has proclaimed 2008, the central year of the triennium, as the UN Year of Planet Earth. This paper describes who is behind the initiative,how it will work, and how the political process leading to United Nations proclamation proceeded. It also describes the financial and organisational aspects of the International Year, sets out the commitments necessary for the realization of the Year's ambitions by all nations, and explains how the raising of US$ 20 million will be approached.
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OpenEarth : Using Google Earth as outreach for NCK's data
de Boer, G.J.; Baart, F.; Bruens, A.; Damsma, T.; van Geer, P.; Grasmeijer, B.; den Heijer, C.; van Koningsveld, M.; Santinelli, G.
2012-01-01
In 2003 various projects at Deltares and the TU-Delft merged their toolboxes for marine and coastal science and engineering into one toolbox, culminating in 2008 in an open source release, known as OpenEarthTools (OET). OpenEarth adopts the wikipedia approach to growth: web 2.0 crowd sourcing. All
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Rare earths: occurrence, production and applications
International Nuclear Information System (INIS)
Murthy, T.K.S.; Mukherjee, T.K.
2002-01-01
The mining and processing of rare earth minerals, particularly of monazite, began in a modest way in 1880s for commercialized production of mantle for gas lighting. For all major applications up to mid-twentieth century- production of lighter flints, misch metal as a metallurgical alloying agent, colouring, decolourizing and polishing agents for glass, petroleum cracking catalysts and arc-carbons, unseparated or partially separated rare earths were adequate. These applications continue till today. With the development and industrial application of powerful techniques like ion exchange and solvent extraction for the separation of rare earths, the decades after 1960 saw increasing utilization of the specific properties of the individual rare earths. Some of these advanced technological applications include: special glass for optical systems including camera lenses, phosphors for colour television, cathode ray tubes and fluorescent lighting, X-ray intensification screens, high intensity permanent magnets, electro optical devices, lasers, hydrogen storage materials, hydride rechargeable batteries, photomagnetic data storage systems, autoexhaust catalysts, special ceramics of unusual toughness, artificial diamonds and nonpoisonous plastic colorants. The topics covered in the book include rare earths: their story identity, rare earth resources, processing of ores and recovery of mixed rare earths products, separation and purification of rare earths, nonmetallic applications of rare earths, rare earth metals: production and applications, rare earth alloys and their applications, analysis of rare earth, processing of rare earth resources in India by Indian Rare Earth Ltd. and availability and market conditions
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Emergence of silicic continents as the lower crust peels off on a hot plate-tectonic Earth
Chowdhury, Priyadarshi; Gerya, Taras; Chakraborty, Sumit
2017-09-01
The rock record and geochemical evidence indicate that continental recycling has been occurring since the early history of the Earth. The stabilization of felsic continents in place of Earth's early mafic crust about 3.0 to 2.0 billion years ago, perhaps due to the initiation of plate tectonics, implies widespread destruction of mafic crust during this time interval. However, the physical mechanisms of such intense recycling on a hotter, (late) Archaean and presumably plate-tectonic Earth remain largely unknown. Here we use thermomechanical modelling to show that extensive recycling via lower crustal peeling-off (delamination but not eclogitic dripping) during continent-continent convergence was near ubiquitous during the late Archaean to early Proterozoic. We propose that such destruction of the early mafic crust, together with felsic magmatism, may have caused both the emergence of silicic continents and their subsequent isostatic rise, possibly above the sea level. Such changes in the continental character have been proposed to influence the Great Oxidation Event and, therefore, peeling-off plate tectonics could be the geodynamic trigger for this event. A transition to the slab break-off controlled syn-orogenic recycling occurred as the Earth aged and cooled, leading to reduced recycling and enhanced preservation of the continental crust of present-day composition.
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The earth's gravitational field
Digital Repository Service at National Institute of Oceanography (India)
Ramprasad, T.
. But to say that gravity acts downwards is not correct. Gravity acts down, no matter where you stand on the Earth. It is better to say that on Earth gravity pulls objects towards the centre of the Earth. So no matter where you are on Earth all objects fall... pull than objects at the poles. In combination, the equatorial bulge and the effects of centrifugal force mean that sea-level gravitational acceleration increases from about 9.780 m/s² at the equator to about 9.832 m/s² at the poles, so an object...
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Rare earths 1998 market update
International Nuclear Information System (INIS)
Tourre, J.M.
1998-01-01
The rare earth industry has always been a world of rapid change with the emergence of new markets, new ores and new players, as well as the disappearance of old applications. Rare earth based products are used in a great diversity of applications such as hard disk drives, CD drives, batteries, capacitors, pigments, ceramics, polishing powders, fuel cells, flints, catalyst converter, fluid cracking catalysts, etc. South East Asia holds the largest share of the known reserve of rare earth ores and is one of the major markets for rare earth compounds; in the last ten years, China has become the largest producer of rare earth intermediates as well as an important exporter of separated rare earth elements. Today, China has approximately 150 factories producing rare earth compounds, most of which are experiencing financial difficulties due to the lack of knowledge of true market needs, lack of control of their distribution channels and production over-capacity. Recently the Chinese rare earth producers have recognized the situation and efforts are underway to rationalize rare earth production. Japan has dominated many of the major application markets, and is by far the largest market for metal and alloy products. This will remain the case for the next five years; however, new countries are emerging as significant users of rare earth products such as Korea, Taiwan and Malaysia. During the last ten years rare earth producers adjusted to several radical changes that affected the raw materials, the application mix and the price structure. New producers have emerged, especially from China; some have subsequently stopped their activities while others have focused their efforts in a specific market segment
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Sun-Earth Scientists and Native Americans Collaborate on Sun-Earth Day
Ng, C. Y.; Lopez, R. E.; Hawkins, I.
2004-12-01
Sun-Earth Connection scientists have established partnerships with several minority professional societies to reach out to the blacks, Hispanics and Native American students. Working with NSBP, SACNAS, AISES and NSHP, SEC scientists were able to speak in their board meetings and national conferences, to network with minority scientists, and to engage them in Sun-Earth Day. Through these opportunities and programs, scientists have introduced NASA research results as well indigenous views of science. They also serve as role models in various communities. Since the theme for Sun-Earth Day 2005 is Ancient Observatories: Timeless Knowledge, scientists and education specialists are hopeful to excite many with diverse backgrounds. Sun-Earth Day is a highly visible annual program since 2001 that touches millions of students and the general public. Interviews, classroom activities and other education resources are available on the web at sunearthday.nasa.gov.
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Turner, D. L.; Omidi, N.; Sibeck, D. G.; Angelopoulos, V.
2011-01-01
Earth?s foreshock, which is the quasi-parallel region upstream of the bow shock, is a unique plasma region capable of generating several kinds of large-scale phenomena, each of which can impact the magnetosphere resulting in global effects. Interestingly, such phenomena have also been observed at planetary foreshocks throughout our solar system. Recently, a new type of foreshock phenomena has been predicted: foreshock bubbles, which are large-scale disruptions of both the foreshock and incident solar wind plasmas that can result in global magnetospheric disturbances. Here we present unprecedented, multi-point observations of foreshock bubbles at Earth using a combination of spacecraft and ground observations primarily from the Time History of Events and Macroscale Interactions during Substorms (THEMIS) mission, and we include detailed analysis of the events? global effects on the magnetosphere and the energetic ions and electrons accelerated by them, potentially by a combination of first and second order Fermi and shock drift acceleration processes. This new phenomena should play a role in energetic particle acceleration at collisionless, quasi-parallel shocks throughout the Universe.
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Energy Technology Data Exchange (ETDEWEB)
Kosygin, Yu A
1986-12-01
Rocks, the age of which according to certain data exceeds considerably the recognized age of the Earth and approximates the age of the Universe, have been detected on the Earth. There is a necessity to coordinate the geological data with cosmological structures.
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Baltic Earth - Earth System Science for the Baltic Sea Region
Meier, Markus; Rutgersson, Anna; Lehmann, Andreas; Reckermann, Marcus
2014-05-01
The Baltic Sea region, defined as its river catchment basin, spans different climate and population zones, from a temperate, highly populated, industrialized south with intensive agriculture to a boreal, rural north. It encompasses most of the Scandinavian Peninsula in the west; most of Finland and parts of Russia, Belarus, and the Baltic states in the east; and Poland and small parts of Germany and Denmark in the south. The region represents an old cultural landscape, and the Baltic Sea itself is among the most studied sea areas of the world. Baltic Earth is the new Earth system research network for the Baltic Sea region. It is the successor to BALTEX, which was terminated in June 2013 after 20 years and two successful phases. Baltic Earth stands for the vision to achieve an improved Earth system understanding of the Baltic Sea region. This means that the research disciplines of BALTEX continue to be relevant, i.e. atmospheric and climate sciences, hydrology, oceanography and biogeochemistry, but a more holistic view of the Earth system encompassing processes in the atmosphere, on land and in the sea as well as in the anthroposphere shall gain in importance in Baltic Earth. Specific grand research challenges have been formulated, representing interdisciplinary research questions to be tackled in the coming years. A major means will be scientific assessments of particular research topics by expert groups, similar to the BACC approach, which shall help to identify knowledge gaps and develop research strategies. Preliminary grand challenges and topics for which Working Groups have been installed include: • Salinity dynamics in the Baltic Sea • Land-Sea biogeochemical feedbacks in the Baltic Sea region • Natural hazards and extreme events in the Baltic Sea region • Understanding sea level dynamics in the Baltic Sea • Understanding regional variability of water and energy exchange • Utility of Regional Climate Models • Assessment of Scenario Simulations
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Carter, William D.
1981-01-01
A large number of Earth-observation satellites orbit our world several times each day, providing new information about the land and sea surfaces and the overlying thin layer of atmosphere that makes our planet unique. Meteorological satellites have had the longest history of experimental use and most are now considered operational. The geologic information collected by the Landsat, Polar Orbiting Geophysical Observatory (POGO), Magsat, Heat Capacity Mapping Mission (HCMM) and Seasat land and ocean observation systems is being thoroughly tested, and some of these systems are now approaching operational use.
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Why did life develop on the surface of the Earth in the Cambrian?
Directory of Open Access Journals (Sweden)
Carlo Doglioni
2016-11-01
Full Text Available Life was limited for most of Earth's history, remaining at a primitive stage and mostly marine until about 0.55 Ga. In the Paleozoic, life eventually exploded and colonized the continental realm. Why had there been such a long period of delayed evolution of life? Early life was dominated by Archaea and Bacteria, which can survive ionizing radiation better than other organisms. The magnetic field preserves the atmosphere, which is the main shield of UV radiation. We explore the hypothesis that the Cambrian explosion of life could have been enabled by the increase of the magnetic field dipole intensity due to the solidification of the inner core, caused by the cooling of the Earth, and the concomitant decrease with time of the high-energy solar flux since the birth of the solar system. Therefore, the two phenomena could be responsible for the growth and thickening of the atmosphere and the development of land surface life.
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DEFF Research Database (Denmark)
Wolff, Stefan
2006-01-01
, Near Earth Objects: Asteroids and comets following paths that bring them near the Earth. NEOs have collided with the Earth since its formation, some causing local devastation, some causing global climate changes, yet the threat from a collision with a near Earth object has only recently been recognised...... and accepted. The European Space Agency mission Gaia is a proposed space observatory, designed to perform a highly accurate census of our galaxy, the Milky Way, and beyond. Through accurate measurement of star positions, Gaia is expected to discover thousands of extra-solar planets and follow the bending...... of starlight by the Sun, and therefore directly observe the structure of space-time. This thesis explores several aspects of the observation of NEOs with Gaia, emphasising detection of NEOs and the quality of orbits computed from Gaia observations. The main contribution is the work on motion detection...
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International Nuclear Information System (INIS)
Kelley, M.C.
1978-01-01
The earth becomes charged during thunderstorm activity and discharges through the weak conducting atmosphere. Balloon and rocket studies infer that a high altitude electric field penetrates virtually unattenuated through the atmosphere, at least as far as balloon heights. The field has two primary sources. At low and mid latitudes, interaction between the earth's magnetic field and the neutral wind creates electric fields. At latitudes above 60 0 , the high altitude electrical structure is dominated by the interaction between the solar wind and the earth's magnetic field. The auroral light is emitted by atmospheric atoms and molecules excited by electrons with potentials of many thousands volts. The potentials are induced by the solar wind. Recent satellite data shows that the electrons get this energy by passing through a localized electric field about 6000 km above the auroral zone. Several rocket and satellite experiments used to study the earth's electric field are discussed
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The Chinese Society of Rare Earth is Studying The Feasibility of Marketing Rare Earth Futures
Institute of Scientific and Technical Information of China (English)
2015-01-01
Lin Donglu,secretary-general of the Chinese Society of Rare Earth recently said,the Chinese Society of Rare Earth undertook the research on subject of the National Social Science Fund Foundation on the reform of Chinese rare earth trading pricing mechanism on promoting RMB globalization,and is focusing on studying the feasibility of marketing rare earth futures variety.
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The fossil history of pseudoscorpions (Arachnida: Pseudoscorpiones
Directory of Open Access Journals (Sweden)
D. Harms
2017-08-01
Full Text Available Pseudoscorpions, given their resemblance to scorpions, have attracted human attention since the time of Aristotle, although they are much smaller and lack the sting and elongated tail. These arachnids have a long evolutionary history but their origins and phylogenetic affinities are still being debated. Here, we summarise their fossil record based on a comprehensive review of the literature and data contained in other sources. Pseudoscorpions are one of the oldest colonisers of the land, with fossils known since the Middle Devonian (ca. 390 Ma. The only arachnid orders with an older fossil record are scorpions, harvestmen and acariform mites, plus two extinct groups. Pseudoscorpions do not fossilise easily, and records from the Mesozoic and Cenozoic consist almost exclusively of amber inclusions. Most Mesozoic fossils come from Archingeay and Burmese ambers (Late Cretaceous and those from the Cenozoic are primarily from Eocene Baltic amber, although additional fossils from, for example, Miocene Dominican and Mexican ambers, are known. Overall, 16 of the 26 families of living pseudoscorpions have been documented from fossils and 49 currently valid species are recognised in the literature. Pseudoscorpions represent a case of morphological stasis and even the Devonian fossils look rather modern. Indeed, most amber fossils are comparable to Recent groups despite a major gap in the fossil record of almost 250 Myr. Baltic amber inclusions indicate palaeofauna inhabiting much warmer climates than today and point to climatic shifts in central Europe since the Eocene. They also indicate that some groups (e.g. Feaellidae and Pseudogarypidae had much wider Eocene distributions. Their present-day occurrence is relictual and highlights past extinction events. Faunas from younger tropical amber deposits (e.g. Dominican and Mexican amber are comparable to Recent ones. Generally, there is a strong bias in the amber record towards groups that live under tree
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10Be and 14C in the Earth system
International Nuclear Information System (INIS)
Oeschger, H.; Beer, J.; Andree, M.
1987-01-01
In a very short period of time, 10 Be data have significantly improved our knowledge in various fields of Earth and planetary sciences. Examples are solar modulation of isotope production, revealed in 10 Be ice-core profiles; geomagnetic modulation of isotope production, revealed in 10 Be ice-core (from the past 10 ka) and ocean-sediment profiles (geomagnetic reversals); climatic effects reflected in 10 Be profiles in loess and polar ice cores ( 10 Be behaviour in atmosphere); comparison of 10 Be and 14 C variations (tree rings) from carbon-cycle models and information on ocean circulation history from 14 C measurements on benthic and planktonic Foraminifera in ocean sediments. An overview on work in collaboration with the Zurich AMS (accelerator mass spectroscopy) facility is given. (author)
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Nimbus-7 Earth radiation budget calibration history. Part 1: The solar channels
Kyle, H. Lee; Hoyt, Douglas V.; Hickey, John R.; Maschhoff, Robert H.; Vallette, Brenda J.
1993-01-01
The Earth Radiation Budget (ERB) experiment on the Nimbus-7 satellite measured the total solar irradiance plus broadband spectral components on a nearly daily basis from 16 Nov. 1978, until 16 June 1992. Months of additional observations were taken in late 1992 and in 1993. The emphasis is on the electrically self calibrating cavity radiometer, channel 10c, which recorded accurate total solar irradiance measurements over the whole period. The spectral channels did not have inflight calibration adjustment capabilities. These channels can, with some additional corrections, be used for short-term studies (one or two solar rotations - 27 to 60 days), but not for long-term trend analysis. For channel 10c, changing radiometer pointing, the zero offsets, the stability of the gain, the temperature sensitivity, and the influences of other platform instruments are all examined and their effects on the measurements considered. Only the question of relative accuracy (not absolute) is examined. The final channel 10c product is also compared with solar measurements made by independent experiments on other satellites. The Nimbus experiment showed that the mean solar energy was about 0.1 percent (1.4 W/sqm) higher in the excited Sun years of 1979 and 1991 than in the quiet Sun years of 1985 and 1986. The error analysis indicated that the measured long-term trends may be as accurate as +/- 0.005 percent. The worse-case error estimate is +/- 0.03 percent.
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International Nuclear Information System (INIS)
Bondar', I.A.; Vinogradova, N.V.; Dem'yanets, L.N.
1983-01-01
From the viewpoint of structural chemistry and general regularities controlling formation reactions of compounds and phases in melts, solid and gaseous states, recent achievements in the chemistry of rare earth germanates are generalized. Methods of synthesizing germanates, systems on the base of germanium oxides and rare earths are considered. The data on crystallochemical characteristics are tabulated. Individual compounds of scandium germanate are also characterized. Processes of germanate formation using the data of IR-spectroscopy, X-ray phase analysis are studied. The structure and morphotropic series of rare earth germanates and silicates are determined. Fields of their present and possible future application are considered
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Lissauer, Jack J.; Barnes, Jason W.; Chambers, John E.
2013-01-01
We numerically explore the obliquity (axial tilt) variations of a hypothetical moonless Earth. Previous work has shown that the Earth's Moon stabilizes Earth's obliquity such that it remains within a narrow range, between 22.1 deg and 24.5 deg. Without lunar influence, a frequency-map analysis by Laskar et al. showed that the obliquity could vary between 0 deg. and 85 deg. This has left an impression in the astrobiology community that a large moon is necessary to maintain a habitable climate on an Earth-like planet. Using a modified version of the orbital integrator mercury, we calculate the obliquity evolution for moonless Earths with various initial conditions for up to 4 Gyr. We find that while obliquity varies significantly more than that of the actual Earth over 100,000 year timescales, the obliquity remains within a constrained range, typically 20-25 deg. in extent, for timescales of hundreds of millions of years. None of our Solar System integrations in which planetary orbits behave in a typical manner show obliquity accessing more than 65% of the full range allowed by frequency-map analysis. The obliquities of moonless Earths that rotate in the retrograde direction are more stable than those of pro-grade rotators. The total obliquity range explored for moonless Earths with rotation periods shorter than 12 h is much less than that for slower-rotating moonless Earths. A large moon thus does not seem to be needed to stabilize the obliquity of an Earth-like planet on timescales relevant to the development of advanced life.
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Water Content of Earth's Continental Mantle Is Controlled by the Circulation of Fluids or Melts
Peslier, Anne; Woodland, Alan B.; Bell, David R.; Lazarov, Marina; Lapen, Thomas J.
2014-01-01
A key mission of the ARES Directorate at JSC is to constrain models of the formation and geological history of terrestrial planets. Water is a crucial parameter to be measured with the aim to determine its amount and distribution in the interior of Earth, Mars, and the Moon. Most of that "water" is not liquid water per se, but rather hydrogen dissolved as a trace element in the minerals of the rocks at depth. Even so, the middle layer of differentiated planets, the mantle, occupies such a large volume and mass of each planet that when it is added at the planetary scale, oceans worth of water could be stored in its interior. The mantle is where magmas originate. Moreover, on Earth, the mantle is where the boundary between tectonic plates and the underlying asthenosphere is located. Even if mantle rocks in Earth typically contain less than 200 ppm H2O, such small quantities have tremendous influence on how easily they melt (i.e., the more water there is, the more magma is produced) and deform (the more water there is, the less viscous they are). These two properties alone emphasize that to understand the distribution of volcanism and the mechanism of plate tectonics, the water content of the mantle must be determined - Earth being a template to which all other terrestrial planets can be compared.
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International Nuclear Information System (INIS)
Delipetrev, Marjan; Delipetrev, Blagoj; Panovska, Sanja
2008-01-01
In this paper is introduced the theory of geomagnetic field of the Earth. A homogenous and isotropic sphere is taken for a model of Earth with a bar magnet at its center as a magnetic potential. The understanding of the real origin of geomagnetic field produced from differential rotation of inner core with respect to the outer core of Earth is here presented. Special attention is given to the latest observed data of the established net of geomagnetic repeat stations in the Republic of Macedonia. Finally, the maps of elements of geomagnetic field and the equation for calculation of normal magnetic field of Earth are provided. (Author)
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A brief history of fruits and frugivores
Fleming, Theodore H.; John Kress, W.
2011-11-01
In this paper we briefly review the evolutionary history of the mutualistic interaction between angiosperms that produce fleshy fruits and their major consumers: frugivorous birds and mammals. Fleshy fruits eaten by these vertebrates are widely distributed throughout angiosperm phylogeny. Similarly, a frugivorous diet has evolved independently many times in birds and mammals. Bird dispersal is more common than mammal-dispersal in all lineages of angiosperms, and we suggest that the evolution of bird fruits may have facilitated the evolution of frugivory in primates. The diets of fruit-eating bats overlap less with those of other kinds of frugivorous vertebrates. With a few exceptions, most families producing vertebrate-dispersed fruit appeared substantially earlier in earth history than families of their vertebrate consumers. It is likely that major radiations of these plants and animals have occurred in the past 30 Ma, in part driven by geological changes and also by the foraging behavior of frugivores in topographically complex landscapes. Overall, this mutualistic interaction has had many evolutionary and ecological consequences for tropical plants and animals for most of the Cenozoic Era. Loss of frugivores and their dispersal services will have a strong negative impact on the ecological and evolutionary dynamics of tropical and subtropical communities.
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Popov, Aleksey
2013-04-01
The magnetic field of the Earth has global meaning for a life on the Earth. The world geophysical science explains: - occurrence of a magnetic field of the Earth it is transformation of kinetic energy of movements of the fused iron in the liquid core of Earth - into the magnetic energy; - the warming up of a kernel of the Earth occurs due to radioactive disintegration of elements, with excretion of thermal energy. The world science does not define the reasons: - drift of a magnetic dipole on 0,2 a year to the West; - drift of lithospheric slabs and continents. The author offers: an alternative variant existing in a world science the theories "Geodynamo" - it is the theory « the Magnetic field of the Earth », created on the basis of physical laws. Education of a magnetic field of the Earth occurs at moving the electric charge located in a liquid kernel, at rotation of the Earth. At calculation of a magnetic field is used law the Bio Savara for a ring electric current: dB = . Magnetic induction in a kernel of the Earth: B = 2,58 Gs. According to the law of electromagnetic induction the Faradey, rotation of a iron kernel of the Earth in magnetic field causes occurrence of an electric field Emf which moves electrons from the center of a kernel towards the mantle. So of arise the radial electric currents. The magnetic field amplifies the iron of mantle and a kernel of the Earth. As a result of action of a radial electric field the electrons will flow from the center of a kernel in a layer of an electric charge. The central part of a kernel represents the field with a positive electric charge, which creates inverse magnetic field Binv and Emfinv When ?mfinv = ?mf ; ?inv = B, there will be an inversion a magnetic field of the Earth. It is a fact: drift of a magnetic dipole of the Earth in the western direction approximately 0,2 longitude, into a year. Radial electric currents a actions with the basic magnetic field of a Earth - it turn a kernel. It coincides with laws
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Safety aspects in rare earths recovery
International Nuclear Information System (INIS)
Bhattacharya, R.
2014-01-01
Recovery of rare earths involves mining of beach sands, mineral separation to obtain monazite and its chemical processing to obtain rare earth composites. The composites are then subjected to further chemical treatment to obtain individual rare earths. Although the separated out rare earths are not radioactive, the process for recovery of rare earths involve both radiological as well as conventional hazards. This paper highlights the safety aspects in the mining, mineral separation and chemical processing of monazite to obtain rare earths
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Our Mission to Planet Earth: A guide to teaching Earth system science
1994-01-01
Volcanic eruptions, hurricanes, floods, and El Nino are naturally occurring events over which humans have no control. But can human activities cause additional environmental change? Can scientists predict the global impacts of increased levels of pollutants in the atmosphere? Will the planet warm because increased levels of greenhouse gases, produced by the burning of fossil fuels, trap heat and prevent it from being radiated back into space? Will the polar ice cap melt, causing massive coastal flooding? Have humans initiated wholesale climatic change? These are difficult questions, with grave implications. Predicting global change and understanding the relationships among earth's components have increased in priority for the nation. The National Aeronautics and Space Administration (NASA), along with many other government agencies, has initiated long-term studies of earth's atmosphere, oceans, and land masses using observations from satellite, balloon, and aircraft-borne instruments. NASA calls its research program Mission to Planet Earth. Because NASA can place scientific instruments far above earth's surface, the program allows scientists to explore earth's components and their interactions on a global scale.
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Energy Technology Data Exchange (ETDEWEB)
Hidaka, Hiroshi; Sakuma, Keisuke [Department of Earth and Planetary Sciences, Nagoya University Nagoya 464-8601 (Japan); Nishiizumi, Kunihiko [Space Sciences Laboratory, University of California, Berkeley, CA 94720-7450 (United States); Yoneda, Shigekazu, E-mail: hidaka@eps.nagoya-u.ac.jp [Department of Science and Engineering, National Museum of Nature and Science Tsukuba 305-0005 (Japan)
2017-06-01
It is known that most lunar meteorites have complicated cosmic-ray exposure experiences on the Moon and in space. In this study, cosmic-ray irradiation histories of six lunar meteorites, Dhofar 489, Northwest Africa 032 (NWA 032), NWA 479, NWA 482, NWA 2995, and NWA 5000, were characterized from neutron-captured isotopic shifts of Sm and Gd, and from the abundances of long-lived cosmogenic radionuclides like {sup 10}Be, {sup 26}Al, {sup 36}Cl, and {sup 41}Ca. Sm and Gd isotopic data of all of six meteorites show significant isotopic shifts of {sup 149}Sm–{sup 150}Sm and {sup 157}Gd–{sup 158}Gd caused by accumulation of neutron capture reactions due to cosmic-ray irradiation, corresponding to the neutron fluences of (1.3–9.6) × 10{sup 16} n cm{sup −2}. In particular, very large Sm and Gd isotopic shifts of NWA 482 are over those of a lunar regolith 70002, having the largest isotopic shifts among the Apollo regolith samples, corresponding to cosmic-ray exposure duration over 800 million years in the lunar surface (2 π irradiation). Meanwhile, the concentrations of cosmogenic radionuclides for individual six meteorites show the short irradiation time less than one million years as their bodies in space (4 π irradiation). Our data also support the results of previous studies, revealing that most of lunar meteorites have long exposure ages at shallow depths on the Moon and short transit times from the Moon to the Earth.
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Moving Closer to EarthScope: A Major New Initiative for the Earth Sciences*
Simpson, D.; Blewitt, G.; Ekstrom, G.; Henyey, T.; Hickman, S.; Prescott, W.; Zoback, M.
2002-12-01
EarthScope is a scientific research and infrastructure initiative designed to provide a suite of new observational facilities to address fundamental questions about the evolution of continents and the processes responsible for earthquakes and volcanic eruptions. The integrated observing systems that will comprise EarthScope capitalize on recent developments in sensor technology and communications to provide Earth scientists with synoptic and high-resolution data derived from a variety of geophysical sensors. An array of 400 broadband seismometers will spend more than ten years crossing the contiguous 48 states and Alaska to image features that make up the internal structure of the continent and underlying mantle. Additional seismic and electromagnetic instrumentation will be available for high resolution imaging of geological targets of special interest. A network of continuously recording Global Positioning System (GPS) receivers and sensitive borehole strainmeters will be installed along the western U.S. plate boundary. These sensors will measure how western North America is deforming, what motions occur along faults, how earthquakes start, and how magma flows beneath active volcanoes. A four-kilometer deep observatory bored directly into the San Andreas fault will provide the first opportunity to observe directly the conditions under which earthquakes occur, to collect fault rocks and fluids for laboratory study, and to monitor continuously an active fault zone at depth. All data from the EarthScope facilities will be openly available in real-time to maximize participation from the scientific community and to provide on-going educational outreach to students and the public. EarthScope's sensors will revolutionize observational Earth science in terms of the quantity, quality and spatial extent of the data they provide. Turning these data into exciting scientific discovery will require new modes of experimentation and interdisciplinary cooperation from the Earth
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Earth science big data at users' fingertips: the EarthServer Science Gateway Mobile
Barbera, Roberto; Bruno, Riccardo; Calanducci, Antonio; Fargetta, Marco; Pappalardo, Marco; Rundo, Francesco
2014-05-01
The EarthServer project (www.earthserver.eu), funded by the European Commission under its Seventh Framework Program, aims at establishing open access and ad-hoc analytics on extreme-size Earth Science data, based on and extending leading-edge Array Database technology. The core idea is to use database query languages as client/server interface to achieve barrier-free "mix & match" access to multi-source, any-size, multi-dimensional space-time data -- in short: "Big Earth Data Analytics" - based on the open standards of the Open Geospatial Consortium Web Coverage Processing Service (OGC WCPS) and the W3C XQuery. EarthServer combines both, thereby achieving a tight data/metadata integration. Further, the rasdaman Array Database System (www.rasdaman.com) is extended with further space-time coverage data types. On server side, highly effective optimizations - such as parallel and distributed query processing - ensure scalability to Exabyte volumes. In this contribution we will report on the EarthServer Science Gateway Mobile, an app for both iOS and Android-based devices that allows users to seamlessly access some of the EarthServer applications using SAML-based federated authentication and fine-grained authorisation mechanisms.
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Anoxygenic photosynthesis modulated Proterozoic oxygen and sustained Earth's middle age
Johnston, D. T.; Wolfe-Simon, F.; Pearson, A.; Knoll, A. H.
2009-01-01
Molecular oxygen (O2) began to accumulate in the atmosphere and surface ocean ca. 2,400 million years ago (Ma), but the persistent oxygenation of water masses throughout the oceans developed much later, perhaps beginning as recently as 580–550 Ma. For much of the intervening interval, moderately oxic surface waters lay above an oxygen minimum zone (OMZ) that tended toward euxinia (anoxic and sulfidic). Here we illustrate how contributions to primary production by anoxygenic photoautotrophs (including physiologically versatile cyanobacteria) influenced biogeochemical cycling during Earth's middle age, helping to perpetuate our planet's intermediate redox state by tempering O2 production. Specifically, the ability to generate organic matter (OM) using sulfide as an electron donor enabled a positive biogeochemical feedback that sustained euxinia in the OMZ. On a geologic time scale, pyrite precipitation and burial governed a second feedback that moderated sulfide availability and water column oxygenation. Thus, we argue that the proportional contribution of anoxygenic photosynthesis to overall primary production would have influenced oceanic redox and the Proterozoic O2 budget. Later Neoproterozoic collapse of widespread euxinia and a concomitant return to ferruginous (anoxic and Fe2+ rich) subsurface waters set in motion Earth's transition from its prokaryote-dominated middle age, removing a physiological barrier to eukaryotic diversification (sulfide) and establishing, for the first time in Earth's history, complete dominance of oxygenic photosynthesis in the oceans. This paved the way for the further oxygenation of the oceans and atmosphere and, ultimately, the evolution of complex multicellular organisms. PMID:19805080
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Seismological evidence for a localized mushy zone at the Earth?s inner core boundary
Tian, Dongdong; Wen, Lianxing
2017-01-01
Although existence of a mushy zone in the Earth?s inner core has been hypothesized several decades ago, no seismic evidence has ever been reported. Based on waveform modeling of seismic compressional waves that are reflected off the Earth?s inner core boundary, here we present seismic evidence for a localized 4?8?km thick zone across the inner core boundary beneath southwest Okhotsk Sea with seismic properties intermediate between those of the inner and outer core and of a mushy zone. Such a ...
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The Earth Information Exchange: A Portal for Earth Science From the ESIP Federation
Wertz, R.; Hutchinson, C.; Hardin, D.
2006-12-01
The Federation of Earth Science Information Partners is a unique consortium of more than 90 organizations that collect, interpret and develop applications for remotely sensed Earth Observation Information. Included in the ESIP network are NASA, NOAA and USGS data centers, research universities, government research laboratories, supercomputer facilities, education resource providers, information technology innovators, nonprofit organizations and commercial enterprises. The consortium's work is dedicated to providing the most up-to-date, science-based information to researchers and decision-makers who are working to understand and address the environmental, economic and social challenges facing our planet. By increasing the use and usability of Earth observation data and linking it with decision-making tools, the Federation partners leverage the value of these important data resources for the betterment of society and our planet. To further the dissemination of Earth Science data, the Federation is developing the Earth Information Exchange (EIE). The EIE is a portal that will provide access to the vast information holdings of the members' organizations in one web-based location and will provides a robust marketplace in which the products and services needed to use and understand this information can be readily acquired. Since the Federation membership includes the federal government's Earth observing data centers, we believe that the impact of the EIE on Earth science research and education and environmental policy making will be profound. In the EIE, Earth observation data, products and services, are organized by the societal benefits categories defined by the international working group developing the Global Earth Observation System of Systems (GEOSS). The quality of the information is ensured in each of the Exchange's issue areas by maintaining working groups of issue area researchers and practitioners who serve as stewards for their respective communities. The
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International Nuclear Information System (INIS)
Coqblin, B.
1982-01-01
This paper reviews the different properties of rare-earths and actinides, either as pure metals or as in alloys or compounds. Three different cases are considered: (i) First, in the case of 'normal' rare-earths which are characterized by a valence of 3, we discuss essentially the magnetic ordering, the coexistence between superconductivity and magnetism and the properties of amorphous rare-earth systems. (ii) Second, in the case of 'anomalous' rare-earths, we distinguish between either 'intermediate-valence' systems or 'Kondo' systems. Special emphasis is given to the problems of the 'Kondo lattice' (for compounds such as CeAl 2 ,CeAl 3 or CeB 6 ) or the 'Anderson lattice' (for compounds such as TmSe). The problem of neutron diffraction in these systems is also discussed. (iii) Third, in the case of actinides, we can separate between the d-f hybridized and almost magnetic metals at the beginning of the series and the rare-earth like the metals after americium. (orig.)
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Flooding Effect on Earth Walls
Directory of Open Access Journals (Sweden)
Meysam Banimahd
2010-12-01
Full Text Available Earth building is a sustainable, environmentally friendly and economical method of construction that has been used worldwide for many centuries. For the past three decades, earth has seen a revival as a building material for a modern construction method due to its benefits in terms of low carbon content, low cost and energy involved during construction, as well as the fact that it is a sustainable technology of building. Climate change is influencing precipitation levels and patterns around the world, and as a consequence, flood risk is increasing rapidly. When flooding occurs, earth buildings are exposed to water by submersion, causing an increase in the degree of saturation of the earth structures and therefore a decrease of the suction between particles. This study investigated the effect of cycles of flooding (consecutive events of flooding followed by dry periods on earth walls. A series of characterization tests were carried out to obtain the physical and mechanical properties of the studied earth material. In a second stage, Flooding Simulation Tests (FST were performed to explore the earth walls’ response to repeated flooding events. The results obtained for the tested earth wall/samples with reinforced material (straw reveal hydraulic hysteresis when wall/samples are subject to cycles of wetting and drying.
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Self-Guided Field Explorations: Integrating Earth Science into Students' Lives
Kirkby, K. C.; Kirkby, S.
2013-12-01
Self-guided field explorations are a simple way to transform an earth science class into a more pedagogically effective experience. Previous experience demonstrated that self-guided student explorations of museum and aquarium exhibits were both extremely popular and remarkably effective. That success led our program to test an expansion of the concept to include self-guided student explorations in outdoor field settings. Preliminary assessment indicates these self-guided field explorations are nearly as popular with students as the museum and aquarium explorations and are as pedagogically effective. Student gains on post-instruction assessment match or exceed those seen in instructor-assisted, hands-on, small group laboratory activities and completely eclipse gains achieved by traditional lecture instruction. As importantly, self-guided field explorations provide a way to integrate field experiences into large enrollment courses where the sheer scale of class trips makes them logistically impossible. This expands course breadth, integrating new topics that could not be as effectively covered by the original class structure. Our introductory program assessed two models of self-guided field explorations. A walking/cycling exploration of the Saint Anthony Falls area, a mile from campus, focuses on the intersections of geological processes with human history. Students explore the geology behind the waterfalls' evolution as well as its subsequent social and economic impacts on human history. A second exploration focuses on the campus area geology, including its building stones as well as its landscape evolution. In both explorations, the goal was to integrate geology with the students' broader understanding of the world they live in. Although the explorations' creation requires a significant commitment, once developed, self-guided explorations are surprisingly low maintenance. These explorations provide a model of a simple, highly effective pedagogical tool that is
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Cosmic growth history and expansion history
International Nuclear Information System (INIS)
Linder, Eric V.
2005-01-01
The cosmic expansion history tests the dynamics of the global evolution of the universe and its energy density contents, while the cosmic growth history tests the evolution of the inhomogeneous part of the energy density. Precision comparison of the two histories can distinguish the nature of the physics responsible for the accelerating cosmic expansion: an additional smooth component--dark energy--or a modification of the gravitational field equations. With the aid of a new fitting formula for linear perturbation growth accurate to 0.05%-0.2%, we separate out the growth dependence on the expansion history and introduce a new growth index parameter γ that quantifies the gravitational modification
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Kargel, J. S.; Beget, J.; Furfaro, R.; Prieto-Ballesteros, O.; Palmero-Rodriguez, J. A.
2007-12-01
Clathrate hydrates are stable through much of the Solar System. These materials and hydrate-like amorphous associations of water with N2, CO, CH4, CO2, O2 and other molecules could, in fact, constitute the bulk of the non-rock components of some icy satellites, comets, and Kuiper Belt Objects. CO2 clathrate is thermodynamically stable at the Martian South Pole surface and could form a significant fraction of both Martian polar caps and icy permafrost distributed across one-third of the Martian surface. CH4 clathrate is the largest clathrate material in Earth's permafrost and cold seafloor regions, and it may be a major volatile reservoir on Mars, too. CO2 clathrate is less abundant on Earth but it might store most of Mars' CO2 inventory and thus may be one of the critical components in the climate system of that planet, just as CH4 clathrate is for Earth. These ice-like phases not only store biologically, geologically, and climatologically important gases, but they also are natural thermal insulators. Thus, they retard the conductive flow of geothermal heat, and thick accumulations of them can modify geotherms, cause brines to exist where otherwise they would not, and induce low-grade metamorphism of upper crustal rocks underlying the insulating bodies. This mechanism of crustal heating may be especially important in assisting hydrogeologic activity on Mars, gas-rich carbonaceous asteroids, icy satellites, and Kuiper Belt Objects. These worlds, compared to Earth, are comparatively energy starved and frozen but may partly make up for their deficit of joules by having large accumulations of joule-conserving hydrates. Thick, continuous layers of clathrate may seal in gases and produce high gas fugacities in aquifers underlying the clathrates, thus producing gas-rich reservoirs capable of erupting violently. This may have happened repeatedly in Earth history, with global climatic consequences for abrupt climate change. We have hypothesized that such eruptions may have
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The Sun Recorded Through History Scientific Data Extracted from Historical Documents
Vázquez, M
2009-01-01
The Sun Recorded Through History is a text that reconstructs past solar activity based on information from historical documents, complementing studies using other techniques. Historical accounts describing phenomena related to solar activity, such as aurorae, sunspots, and corona observed during solar eclipses can be used as a proxy of solar activity in the past. These descriptions are reviewed, on the one hand providing primary material for the history of astronomy and, on the other, verifying or refuting current ideas concerning the time variability of the Sun on the scale of centuries. Documents predating the discovery of photography (around 1840) that contain information on these topics are highlighted, but modern drawings are also included. The lower temporal limit of study is set by the archaeoastronomy of prehistoric sources. In addition, the necessary background on the Sun is provided, with special emphasis on observing techniques and the influences of telescopes and the Earth's atmosphere on the data...
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Marzban, Caren; Viswanathan, Raju; Yurtsever, Ulvi
2014-01-09
A recent study argued, based on data on functional genome size of major phyla, that there is evidence life may have originated significantly prior to the formation of the Earth. Here a more refined regression analysis is performed in which 1) measurement error is systematically taken into account, and 2) interval estimates (e.g., confidence or prediction intervals) are produced. It is shown that such models for which the interval estimate for the time origin of the genome includes the age of the Earth are consistent with observed data. The appearance of life after the formation of the Earth is consistent with the data set under examination.
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Development of an earth pressure model for design of earth retaining structures in piedmont soil.
2008-10-01
Anecdotal evidence suggests that earth pressure in Piedmont residual soils is typically over estimated. Such estimates of earth pressure impact the design of earth retaining structures used on highway projects. Thus, the development of an appropriate...
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At the Interface: Academic History, School History and the Philosophy of History
Retz, Tyson
2016-01-01
How history is learnt and taught must to some extent be shaped by conceptions of what history is. Historians tend to conceptualize what something is by investigating what it has been and what it has meant in different contexts. This article explains how a debate in the philosophy of history between positivism and intentionalism provided the…
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Internally heated mantle convection and the thermal and degassing history of the earth
Williams, David R.; Pan, Vivian
1992-01-01
An internally heated model of parameterized whole mantle convection with viscosity dependent on temperature and volatile content is examined. The model is run for 4l6 Gyr, and temperature, heat flow, degassing and regassing rates, stress, and viscosity are calculated. A nominal case is established which shows good agreement with accepted mantle values. The effects of changing various parameters are also tested. All cases show rapid cooling early in the planet's history and strong self-regulation of viscosity due to the temperature and volatile-content dependence. The effects of weakly stress-dependent viscosity are examined within the bounds of this model and are found to be small. Mantle water is typically outgassed rapidly to reach an equilibrium concentration on a time scale of less than 200 Myr for almost all models, the main exception being for models which start out with temperatures well below the melting temperature.
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Differentiation of crusts and cores of the terrestrial planets: lessons for the early Earth
International Nuclear Information System (INIS)
Solomon, S.C.
1980-01-01
It now appears probable that all of the terrestrial planets underwent some form of global chemical differentiation to produce crusts, mantles, and cores of variable relative mass fractions. There is direct seismic evidence for a crust on the Moon, and indirect evidence for distinct crusts on Mars and Venus. Substantial portions of these crusts have been in place since the time that heavy bombardment of the inner solar system ceased approximately 4 Ga ago. There is direct evidence for a sizeable core on Mars, indirect evidence for one on Mercury, and bounds on a possible small core for the Moon. Core formation is an important heat source confined to times prior to 4 Ga ago for Mercury and the Earth, but was not closely linked to crustal formation on the Moon nor, apparently, on Mars. The tectonic and volcanic histories of the surfaces of the terrestrial planets Moon, Mars, and Mercury can be used, with simple thermal history models, to restrict the earliest chemical differentiation to be shallow (outer 200-400 km) for the first two bodies and much more extensive for Mercury. Extension of these models to an Earth-size planet leads to the prediction of a hot and vigorously convecting mantle with an easily deformable crust immediately following core formation, and of the gradual development of a lithosphere and of plates with some lateral rigidity in Late Archean-Proterzoic times. (Auth.)
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Qu, Cheng; Tang, Yu-Ping; Shi, Xu-Qin; Zhou, Gui-Sheng; Shang, Er-Xin; Shang, Li-Li; Guo, Jian-Ming; Liu, Pei; Zhao, Jing; Zhao, Bu-Chang; Duan, Jin-Ao
2017-08-01
To evaluate the promoting blood circulation and removing blood stasis effects of Danshen-Honghua(DH) herb pair with different preparations (alcohol, 50% alcohol and water) on blood rheology and coagulation functions in acute blood stasis rats, and optimize the best preparation method of DH based on principal component analysis(PCA), hierarchical cluster heatmap analysis and multi-attribute comprehensive index methods. Ice water bath and subcutaneous injection of adrenaline were both used to establish the acute blood stasis rat model. Then the blood stasis rats were administrated intragastrically with DH (alcohol, 50% alcohol and water) extracts. The whole blood viscosity(WBV), plasma viscosity(PV), erythrocyte sedimentation rate(ESR) and haematocrit(HCT) were tested to observe the effects of DH herb pair with different preparations and doses on hemorheology of blood stasis rats; the activated partial thromboplastin time(APTT), thrombin time(TT), prothrombin time(PT), and plasma fibrinogen(FIB) were tested to observe the effects of DH herb pair with different preparations on blood coagulation function and platelet aggregation of blood stasis rats. Then PCA, hierarchical cluster heatmap analysis and multi-attribute comprehensive index methods were all used to comprehensively evaluate the total promoting blood circulation and removing blood stasis effects of DH herb pair with different preparations. The hemorheological indexes and coagulation parameters of model group had significant differences with normal blank group. As compared with the model group, the DH herb pair with different preparations at low, middle and high doses could improve the blood hemorheology indexes and coagulation parameters in acute blood stasis rats with dose-effect relation. Based on the PCA, hierarchical cluster heatmap analysis and multi-attribute comprehensive index methods, the high dose group of 50% alcohol extract had the best effect of promoting blood circulation and removing blood
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The discovery of radioactivity: a bend in sciences history
International Nuclear Information System (INIS)
Dautray, R.
1997-01-01
One hundred years after the discovery of radioactivity, it is possible to see what are the consequences of this discovery for the science. Four consequences are studied in this article: the acquisition of a new knowledge about matter and universe. Secondly, the observation that the radioactivity has given a clock of world history and open to us the past and how this past forged the present world. Thirdly, the fact that radioactivity gave tracers, markers which allow to sound the internal structure of the human body as well as these one of earth and solar system and to unveil the mechanisms. The fourth consequence, is all the applications, electro-nuclear energy, national defence, nuclear medicine. (N.C.)
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,
2010-01-01
For most of us, deserts, mountains, river valleys, coastlines even dry lakebeds are relatively familiar features of the Earth's terrestrial environment. For earth scientists, they are the focus of considerable scientific research. Viewed from a unique and unconventional perspective, Earth's geographic attributes can also be a surprising source of awe-inspiring art. That unique perspective is space. The artists for the Earth as Art Three exhibit are the Landsat 5 and Landsat 7 satellites, which orbit approximately 705 kilometers (438 miles) above the Earth's surface. While studying the images these satellites beam down daily, researchers are often struck by the sheer beauty of the scenes. Such images inspire the imagination and go beyond scientific value to remind us how stunning, intricate, and simply amazing our planet's features can be. Instead of paint, the medium for these works of art is light. But Landsat satellite sensors don't see light as human eyes do; instead, they see radiant energy reflected from Earth's surface in certain wavelengths, or bands, of red, green, blue, and infrared light. When these different bands are combined into a single image, remarkable patterns, colors, and shapes emerge. The Earth as Art Three exhibit provides fresh and inspiring glimpses of different parts of our planet's complex surface. The images in this collection were chosen solely based on their aesthetic appeal. Many of the images have been manipulated to enhance color variations or details. They are not intended for scientific interpretation only for your viewing pleasure. Enjoy!
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Galileo's Religion Versus the Church's Science? Rethinking the History of Science and Religion
Wilson, D. B.
Galileo's conflict with the Catholic Church is well recognized as a key episode in the history of physics and in the history of science and religion. This paper applies a new, historiographical approach to that specific episode. It advocates eliminating the science and religion. The Church concluded that the plainest facts of human experience agreed perfectly with an omniscient God's revealed word to proclaim the earth at rest. Supported by the Bible, Galileo, God-like, linked the elegance of mathematics to truths about nature. The Church, in effect, resisted Galileo's claim to be able to think like God, instead listening to God himself - and paying close attention to what man himself observed. We can thus see that the phrase ``Galileo's religion versus the Church's science'' is as meaningful (or meaningless) as the usual designation ``Galileo's science versus the Church's religion.''
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History and National Development | Oyeranmi | Journal of History ...
African Journals Online (AJOL)
Volumes of works have been written on the subject of the relevance of history to national development in Nigeria. To „.non historians.. history teaches no particular skill “since the primary focus of history is the past... Does history still serve any purpose especially in the 21st century? What are those values embedded in ...
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Lumban Gaol, Ford; Soewito, Benfano
2015-01-01
The 2nd International Conference on Geological, Geographical, Aerospace and Earth Sciences 2014 (AeroEarth 2014), was held at Discovery Kartika Plaza Hotel, Kuta, Bali, Indonesia during 11 - 12 October 2014. The AeroEarth 2014 conference aims to bring together researchers and engineers from around the world. Through research and development, earth scientists have the power to preserve the planet's different resource domains by providing expert opinion and information about the forces which make life possible on Earth. Earth provides resources and the exact conditions to make life possible. However, with the advent of technology and industrialization, the Earth's resources are being pushed to the brink of depletion. Non-sustainable industrial practices are not only endangering the supply of the Earth's natural resources, but are also putting burden on life itself by bringing about pollution and climate change. A major role of earth science scholars is to examine the delicate balance between the Earth's resources and the growing demands of industrialization. Through research and development, earth scientists have the power to preserve the planet's different resource domains by providing expert opinion and information about the forces which make life possible on Earth. We would like to express our sincere gratitude to all in the Technical Program Committee who have reviewed the papers and developed a very interesting Conference Program as well as the invited and plenary speakers. This year, we received 98 papers and after rigorous review, 17 papers were accepted. The participants come from eight countries. There are four Parallel Sessions and two invited Speakers. It is an honour to present this volume of IOP Conference Series: Earth and Environmental Science (EES) and we deeply thank the authors for their enthusiastic and high-grade contributions. Finally, we would like to thank the conference chairmen, the members of the steering committee, the organizing committee
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COMPASS Final Report: Near Earth Asteroids Rendezvous and Sample Earth Returns (NEARER)
Oleson, Steven R.; McGuire, Melissa L.
2009-01-01
In this study, the Collaborative Modeling for Parametric Assessment of Space Systems (COMPASS) team completed a design for a multi-asteroid (Nereus and 1996 FG3) sample return capable spacecraft for the NASA In-Space Propulsion Office. The objective of the study was to support technology development and assess the relative benefits of different electric propulsion systems on asteroid sample return design. The design uses a single, heritage Orion solar array (SA) (approx.6.5 kW at 1 AU) to power a single NASA Evolutionary Xenon Thruster ((NEXT) a spare NEXT is carried) to propel a lander to two near Earth asteroids. After landing and gathering science samples, the Solar Electric Propulsion (SEP) vehicle spirals back to Earth where it drops off the first sample s return capsule and performs an Earth flyby to assist the craft in rendezvousing with a second asteroid, which is then sampled. The second sample is returned in a similar fashion. The vehicle, dubbed Near Earth Asteroids Rendezvous and Sample Earth Returns (NEARER), easily fits in an Atlas 401 launcher and its cost estimates put the mission in the New Frontier s (NF's) class mission.
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National Aeronautics and Space Administration — The NASA Earth Exchange (NEX) represents a new platform for the Earth science community that provides a mechanism for scientific collaboration and knowledge sharing....
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Earth Science Enterprise Technology Strategy
1999-01-01
NASA's Earth Science Enterprise (ESE) is dedicated to understanding the total Earth system and the effects of natural and human-induced changes on the global environment. The goals of ESE are: (1) Expand scientific knowledge of the Earth system using NASA's unique vantage points of space, aircraft, and in situ platforms; (2) Disseminate information about the Earth system; and (3) Enable the productive use of ESE science and technology in the public and private sectors. ESE has embraced the NASA Administrator's better, faster, cheaper paradigm for Earth observing missions. We are committed to launch the next generation of Earth Observing System (EOS) missions at a substantially lower cost than the EOS first series. Strategic investment in advanced instrument, spacecraft, and information system technologies is essential to accomplishing ESE's research goals in the coming decades. Advanced technology will play a major role in shaping the ESE fundamental and applied research program of the future. ESE has established an Earth science technology development program with the following objectives: (1) To accomplish ESE space-based and land-based program elements effectively and efficiently; and (2) To enable ESE's fundamental and applied research programs goals as stated in the NASA Strategic Plan.
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Using EarthLabs to Enhance Earth Science Curriculum in Texas
Chegwidden, D. M.; Ellins, K. K.; Haddad, N.; Ledley, T. S.
2012-12-01
As an educator in Texas, a state that values and supports an Earth Science curriculum, I find it essential to educate my students who are our future voting citizens and tax payers. It is important to equip them with tools to understand and solve the challenges of solving of climate change. As informed citizens, students can help to educate others in the community with basic knowledge of weather and climate. They can also help to dispose of the many misconceptions that surround the climate change, which is perceived as a controversial topic. As a participant in a NSF-sponsored Texas Earth and Space (TXESS) Revolution teacher professional development program, I was selected to participate in a curriculum development project led by TERC to develop and test education resources for the EarthLabs climate literacy collection. I am involved in the multiple phases of the project, including reviewing labs that comprise the Climate, Weather and Biosphere module during the development phase, pilot teaching the module with my students, participating in research, and delivering professional development to other Texas teachers to expose them to the content found in the module and to encourage them to incorporate it into their teaching. The Climate, Weather and the Biosphere module emphasizes different forms of evidence and requires that learners apply different inquiry-based approaches to build the knowledge they need to develop as climate literate citizens. My involvement with the EarthLabs project has strengthened my overall knowledge and confidence to teach about Earth's climate system and climate change. In addition, the project has produced vigorous classroom discussion among my students as well as encouraged me to collaborate with other educators through our delivery of professional development to other teachers. In my poster, I will share my experiences, describe the impact the curriculum has made on my students, and report on challenges and valuable lessons gained by
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Making a report of a short trip in an ophiolitic complex with Google Earth
Aubret, Marianne
2017-04-01
Plate tectonics is taught in French secondary school (lower and upper-sixth). According to the curriculum, the comprehension of plate-tectonic processes and concepts should be based on field data. For example, the Alpine's ocean history is studied to understand how mountain ranges are formed. In this context, Corsica is a great open-air laboratory, but unfortunately, the traffic conditions are very difficult in the island and despite the short distances, it's almost impossible for teachers to take their students to the remarkable geologic spots. The «défilé de l'Inzecca» is one of them: there you can see a part of the alpine's ophiolitic complex. The aim of this activity is to elaborate a « KMZ folder » in Google Earth as a report of a short trip thanks to the students' data field; it is also the occasion to enrich the Google Earth KMZ folder already available for our teaching.
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Cairns, Brian
2014-01-01
When the solar system formed, the sun was 30 dimmer than today and Venus had an ocean. As the sun brightened, a runaway greenhouse effect caused the Venus ocean to boil away. At times when Earth was younger, the sun less bright, and atmospheric CO2 less, Earth froze over (snowball Earth). Earth is in the sweet spot today. Venus is closer to sun than Earth is, but cloud-covered Venus absorbs only 25 of incident sunlight, while Earth absorbs 70. Venus is warmer because it has a thick carbon dioxide atmosphere causing a greenhouse effect of several hundred degrees. Earth is Goldilocks choice among the planets, the one that is just right for life to exist. Not too hot. Not too cold. How does the Earth manage to stay in this habitable range? Is there a Gaia phenomenon keeping the climate in bounds? A nice idea, but it doesnt work. Today, greenhouse gas levels are unprecedented compared to the last 450,000 years.
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Energy Technology Data Exchange (ETDEWEB)
Ojima, D. [ed.
1992-12-31
The 1990 Global Change Institute (GCI) on Earth System Modeling is the third of a series organized by the Office for Interdisciplinary Earth Studies to look in depth at particular issues critical to developing a better understanding of the earth system. The 1990 GCI on Earth System Modeling was organized around three themes: defining critical gaps in the knowledge of the earth system, developing simplified working models, and validating comprehensive system models. This book is divided into three sections that reflect these themes. Each section begins with a set of background papers offering a brief tutorial on the subject, followed by working group reports developed during the institute. These reports summarize the joint ideas and recommendations of the participants and bring to bear the interdisciplinary perspective that imbued the institute. Since the conclusion of the 1990 Global Change Institute, research programs, nationally and internationally, have moved forward to implement a number of the recommendations made at the institute, and many of the participants have maintained collegial interactions to develop research projects addressing the needs identified during the two weeks in Snowmass.
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The earth's hydrological cycle
Bonnet, R-M; Calisto, M; Destouni, G; Gurney, R; Johannessen, J; Kerr, Y; Lahoz, WA; Rast, M
2014-01-01
This book gives a comprehensive presentation of our present understanding of the Earth's Hydrological cycle and the problems, consequences and impacts that go with this topic. Water is a central component in the Earth's system. It is indispensable for life on Earth in its present form and influences virtually every aspect of our planet's life support system. On relatively short time scales, atmospheric water vapor interacts with the atmospheric circulation and is crucial in forming the Earth's climate zones. Water vapor is the most powerful of the greenhouse gases and serves to enhance the tropospheric temperature. The dominant part of available water on Earth resides in the oceans. Parts are locked up in the land ice on Greenland and Antarctica and a smaller part is estimated to exist as groundwater. If all the ice over the land and all the glaciers were to melt, the sea level would rise by some 80 m. In comparison, the total amount of water vapor in the atmosphere is small; it amounts to ~ 25 kg/m2, or the ...
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Schoeberl, Mark; Rood, Richard B.; Hildebrand, Peter; Raymond, Carol
2003-01-01
The Earth System Model is the natural evolution of current climate models and will be the ultimate embodiment of our geophysical understanding of the planet. These models are constructed from components - atmosphere, ocean, ice, land, chemistry, solid earth, etc. models and merged together through a coupling program which is responsible for the exchange of data from the components. Climate models and future earth system models will have standardized modules, and these standards are now being developed by the ESMF project funded by NASA. The Earth System Model will have a variety of uses beyond climate prediction. The model can be used to build climate data records making it the core of an assimilation system, and it can be used in OSSE experiments to evaluate. The computing and storage requirements for the ESM appear to be daunting. However, the Japanese ES theoretical computing capability is already within 20% of the minimum requirements needed for some 2010 climate model applications. Thus it seems very possible that a focused effort to build an Earth System Model will achieve succcss.
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Planetary dreams : the quest to discover life beyond earth
Shapiro, Robert
1999-03-01
The Quest To Discover Life Beyond Earth. "The 'dreams' that I write of are not the usual ones, the images that come up in our minds involuntarily during certain stages of sleep, but rather the hopes and expectations that we have lavished upon other worlds around us."-from the Preface. The surprisingly long history of debate over extraterrestrial life is full of marvelous visions of what life "out there" might be like, as well as remarkable stories of alleged sightings and heated disputes about the probability that life might actually have arisen more than once. In Planetary Dreams, acclaimed author Robert Shapiro explores this rich history of dreams and debates in search of the best current answers to the most elusive and compelling of all questions: Are we alone? In his pursuit, he presents three contrasting views regarding how life might have started: through Divine Creation, by a highly unlikely stroke of luck, or by the inevitable process of a natural law that he terms the Life Principle. We are treated to a lively fictional dinner debate among the leading proponents of these schools of thought-with the last named group arguing that life has almost surely formed in many places throughout the universe, and the others that life may well be entirely unique to our own blue planet. To set the stage for a deep exploration of the question, the author then leads us on a fantastic journey through the museum of the cosmos, an imagined building that holds models of the universe at different degrees of magnification. We then journey deep into inner space to view the astonishingly intricate life of a single cell, and learn why the origin of such a complex object from simple chemical mixtures poses one of the most profound enigmas known to science. Writing in a wonderfully entertaining style, Shapiro then reviews the competing theories about the start of life on Earth, and suggests the debate may best be settled by finding signs of life on the other worlds of our solar
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A high-orbit collimating infrared earth simulator
International Nuclear Information System (INIS)
Zhang Guoyu; Jiang Huilin; Fang Yang; Yu Huadong; Xu Xiping; Wang, Lingyun; Liu Xuli; Huang Lan; Yue Shixin; Peng Hui
2007-01-01
The earth simulator is the most important testing equipment ground-based for the infrared earth sensor, and it is also a key component in the satellite controlling system. for three orbit heights 18000Km, 35786Km and 42000Km, in this paper we adopt a project of collimation and replaceable earth diaphragm and develop a high orbit collimation earth simulator. This simulator can afford three angles 15.19 0 , 17.46 0 and 30.42 0 , resulting simulating the earth on the ground which can be seen in out space by the satellite. In this paper we introduce the components, integer structure, and the earth's field angles testing method of the earth simulator in detail. Germanium collimation lens is the most important component in the earth simulator. According to the optical configuration parameter of Germanium collimation lens, we find the location and size of the earth diaphragm and the hot earth by theoretical analyses and optics calculation, which offer foundation of design in the study of the earth simulator. The earth angle is the index to scale the precision of earth simulator. We test the three angles by experiment and the results indicate that three angles errors are all less than ±0.05 0
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Near-Earth Reconnection Ejecta at Lunar Distances
Runov, A.; Angelopoulos, V.; Artemyev, A.; Lu, S.; Zhou, X.-Z.
2018-04-01
Near-Earth magnetotail reconnection leads to formation of earthward and tailward directed plasma outflows with an increased north-south magnetic field strength(|Bz|) at their leading edges. We refer to these regions of enhanced |Bz| and magnetic flux transport Ey as reconnection ejecta. They are composed of what have been previously referred to as earthward dipolarizing flux bundles (DFBs) and tailward rapid flux transport (RFT) events. Using two-point observations of magnetic and electric fields and particle fluxes by the Acceleration, Reconnection, Turbulence, and Electrodynamics of Moon's Interaction with the Sun probes orbiting around Moon at geocentric distances R ˜ 60RE, we statistically studied plasma moments and particle energy spectra in RFTs and compared them with those observed within DFBs in the near-Earth plasma sheet by the Time History of Events and Macroscale Interactions during Substorms probes. We found that the ion average temperatures and spectral slopes in RFTs at R ˜ 60RE are close to those in DFBs observed at 15 balance, the average RFT ion temperature corresponds to a lobe field BL˜20 nT. This leads us to suggest that the ion population within the tailward ejecta originated in the midtail plasma sheet at 20≤R≤30RE and propagated to the Acceleration, Reconnection, Turbulence, and Electrodynamics of Moon's Interaction with the Sun location without undergoing any further energy gain. Conversely, electron temperatures in DFBs at 15 < R < 25RE are a factor of 2.5 higher than those in RFTs at R ˜ 60RE.
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Volatile elements - water, carbon, nitrogen, noble gases - on Earth
Marty, B.
2017-12-01
Understanding the origin and evolution of life-bearing volatile elements (water, carbon, nitrogen) on Earth is a fruitful and debated area of research. In his pioneering work, W.W. Rubey inferred that the terrestrial atmosphere and the oceans formed from degassing of the mantle through geological periods of time. Early works on noble gas isotopes were consistent with this view and proposed a catastrophic event of mantle degassing early in Earth's history. We now have evidence, mainly from noble gas isotopes, that several cosmochemical sources contributed water and other volatiles at different stages of Earth's accretion. Potential contributors include the protosolar nebula gas that equilibrated with magma oceans, inner solar system bodies now represented by chondrites, and comets. Stable isotope ratios suggest volatiles where primarily sourced by planetary bodies from the inner solar system. However, recent measurements by the European Space Agency Rosetta probe on the coma of Comet 67P/Churyumov-Gerasimenko permit to set quantitative constraints on the cometary contribution to the surface of our planet. The surface and mantle reservoirs volatile elements exchanged volatile elements through time, with rates that are still uncertain. Some mantle regions remained isolated from whole mantle convection within the first tens to hundreds million years after start of solar system formation. These regions, now sampled by some mantle plumes (e.g., Iceland, Eifel) preserved their volatile load, as indicated by extinct and extant radioactivity systems. The abundance of volatile elements in the mantle is still not well known. Different approaches, such as high pressure experimental petrology, noble gas geochemistry, modelling, resulted in somewhat contrasted estimates, varying over one order of magnitude for water. Comparative planetology, that is, the study of volatiles on the Moon, Venus, Mars, Vesta, will shed light on the sources and strengths of these elements in the
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Energy Technology Data Exchange (ETDEWEB)
Flohn, H
1981-01-01
This Executive Report derives from IIASA Research Report RR-80-30, Possible Climatic Consequences of a Man-Made Global Warming, by H. Flohn and published separately. It is based on research undertaken to explore the interaction between energy and climate, including the impact on the global climate of three main energy sources: solar, nuclear, and fossil fuels. Its findings describe the global warming effects caused by carbon dioxide released by burning fossil fuels and by other trace gases released into the atmosphere. The approach is paleoclimatic; it provides insight into what global warming will produce by considering what is known about past periods of the earth's history when the global average surface temperature was higher than it is now. The purpose of this report is to put the research findings into layman's language and add related information to provide a general introduction to the global warming problem. Information is presented under the following chapter titles: the scenario in brief; the climatic system; changes in ice cover; changes in atmosphere and oceans; man's effect on climate; taking the earth's temperature; what a hotter earth might mean; beyond immediate prospects; and, today's mixed signals. (JGB)
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Raman scattering of rare earth hexaborides
International Nuclear Information System (INIS)
Ogita, Norio; Hasegawa, Takumi; Udagawa, Masayuki; Iga, Fumitoshi; Kunii, Satoru
2009-01-01
Raman scattering spectra were measured for the rare-earth hexaborides RB 6 (R = Ce, Gd, or Dy). All Raman-active phonons due to B 6 vibrations were observed in the range 600 - 1400 cm -1 . Anomalous peaks were detected below 200 cm -1 , which correspond to vibrations of rare-earth ion excited by second-order Raman scattering process. The intensity and energy of the rare-earth mode decrease with decreasing temperature. This suggests that the rare-earth ion vibrates in a shallow and anharmonic potential due to the boron cage. Using the reported values of mean square displacement of rare-earth ion, we estimated the anharmonic contribution for the rare-earth vibrations.
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Gallagher, D. L.
2015-01-01
The Earth's plasmasphere is an inner part of the magneteosphere. It is located just outside the upper ionosphere located in Earth's atmosphere. It is a region of dense, cold plasma that surrounds the Earth. Although plasma is found throughout the magnetosphere, the plasmasphere usually contains the coldest plasma. Here's how it works: The upper reaches of our planet's atmosphere are exposed to ultraviolet light from the Sun, and they are ionized with electrons that are freed from neutral atmospheric particles. The results are electrically charged negative and positive particles. The negative particles are electrons, and the positive particles are now called ions (formerly atoms and molecules). If the density of these particles is low enough, this electrically charged gas behaves differently than it would if it were neutral. Now this gas is called plasma. The atmospheric gas density becomes low enough to support the conditions for a plasma around earth at about 90 kilometers above Earth's surface. The electrons in plasma gain more energy, and they are very low in mass. They move along Earth's magnetic field lines and their increased energy is enough to escape Earth's gravity. Because electrons are very light, they don't have to gain too much kinetic energy from the Sun's ultraviolet light before gravity loses its grip on them. Gravity is not all that holds them back, however. As more and more electrons begin to escape outward, they leave behind a growing net positive electric charge in the ionosphere and create a growing net negative electric charge above the ionosphere; an electric field begins to develop (the Pannekoek-Rosseland E-field). Thus, these different interacting charges result in a positively charged ionosphere and negatively charged region of space above it. Very quickly this resulting electric field opposed upward movement of the electrons out of the ionosphere. The electrons still have this increased energy, however, so the electric field doesn't just
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International Nuclear Information System (INIS)
Smith, H.D.; Smith, M.P.; Schultz, W.E.
1977-01-01
A method for determining the porosity of earth formations in the vicinity of a cased well borehole is described, comprising the steps of: irradiating the earth formations in the vicinity of the cased well borehole with fast neutrons from a source of fast neutrons passed into the borehole; and generating a signal representative of the fast neutron population present in the well borehole at a location in the borehole, the signal is functionally related to the porosity of the earth formations in the vicinity of the borehole
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International Nuclear Information System (INIS)
Ringwood, A.E.
1981-01-01
The composition of the Earth's interior and its bearing on the Earth's origin are discussed. It seems likely that the terrestrial planets formed by the accretion of solid planetisimals from the nebula of dust and gas left behind during the formation of the Sun. The scenario proposed is simpler than others. New evidence based upon a comparison of siderophile element abundances in the Earth's mantle and in the Moon imply that the Moon was derived from the Earth's mantle after the Earth's core had segregated
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Factors Affecting Student Success with a Google Earth-Based Earth Science Curriculum
Blank, Lisa M.; Almquist, Heather; Estrada, Jen; Crews, Jeff
2016-01-01
This study investigated to what extent the implementation of a Google Earth (GE)-based earth science curriculum increased students' understanding of volcanoes, earthquakes, plate tectonics, scientific reasoning abilities, and science identity. Nine science classrooms participated in the study. In eight of the classrooms, pre- and post-assessments…
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STS-39 Earth observation of Earth's limb at sunset shows atmospheric layers
1991-01-01
STS-39 Earth observation taken aboard Discovery, Orbiter Vehicle (OV) 103, shows the Earth's limb at sunset with numerous atmospheric scattering layers highlighted. The layers consist of fine particles suspended in very stable layers of the atmosphere. The layers act as a prism for the sunlight.
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Folta, David; Young, Corissa; Ross, Adam
2001-01-01
The purpose of this investigation is to determine the feasibility of attaining and maintaining unique non-Keplerian orbit vantage locations in the Earth/Moon environment in order to obtain continuous scientific measurements. The principal difficulty associated with obtaining continuous measurements is the temporal nature of astrodynamics, i.e., classical orbits. This investigation demonstrates advanced trajectory designs to meet demanding science requirements which cannot be met following traditional orbital mechanic logic. Examples of continuous observer missions addressed include Earth pole-sitters and unique vertical libration orbits that address Sun-Earth Connection and Earth Science Vision roadmaps.
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Directory of Open Access Journals (Sweden)
Paul M. Arnold
2009-06-01
Full Text Available Synovial sarcoma is an uncommon malignant soft tissue neoplasm, occurring primarily in adolescents and young adults. It is prevalent in the periarticular soft tissues near large joints of the extremities and rarely involves the trunk. Metastases are not uncommon and usually involve the lungs; metastasis to the thoracic spine is rare. We report the case of a 47-year-old man with a history of synovial sarcoma of the lower back, with subsequent metastases to the lung, penis, and perineum (all previously resected, presenting with a 3-month history of low back pain and lower extremity paresthesias. Magnetic resonance imaging (MRI demonstrated multiple lesions involving multiple contiguous vertebral bodies, with the mass at T12 compressing the spinal cord. The patient underwent T11-T12 laminectomy, transpedicular decompression, tumor debulking, and posterior fixation and fusion. The patient died six months later due to disease progression. Although not curative, decompression and stabilization of the spine are often necessary in patients who present spinal cord compression.El sarcoma sinovial es una neoplasia rara de los tejidos blandos que afecta adolescentes y adultos jóvenes. Su mayor prevalencia es en las grandes articulaciones de las extremidades y raramente ataca el tronco. Las lesiones metastásicas son raras y generalmente atacan los pulmones, siendo que las metástasis de columna torácica son raras. Será relatado el cuadro clínico de un paciente de 47 años de edad con tres meses de historia de dolor lumbar y presentando metástasis de sarcoma sinovial en la columna lumbar. La resonancia magnética demostraba lesiones contiguas del cuerpo vertebral y compresión del canal vertebral al nivel de T12. El paciente fue sometido a la laminectomía de T11-T12, descompresión transpedicular, remoción de tejido tumoral y artrodesis con fijación posterior. El paciente fue a óbito después de seis meses debido a la progresión de la enfermedad
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The fifth force: A personal history
Fischbach, Ephraim
2015-12-01
On January 6, 1986, a paper written by our group appeared in Physical Review Letters entitled "Reanalysis of the Eötvös Experiment". In that Letter we reanalyzed a well-known 1922 paper by Eötvös, Pekár, and Fekete (EPF) which compared the accelerations of samples of different composition to the Earth. Our surprising conclusion was that "Although the Eötvös experiment has been universally interpreted as having given null results, we find in fact that this is not the case". Two days later a front page story appeared in the New York Times under the headline "Hints of 5th Force in Universe Challenge Galileo's Findings", and so was born the concept of a "fifth force". In this personal history I review the pre-history which motivated our paper, and discuss details of our reanalysis of the EPF paper that have not been presented previously. Our work led to illuminating correspondence with Robert Dicke and Richard Feynman which are presented here for the first time. I also discuss an interesting meeting with T.D. Lee, one of whose papers with C.N. Yang provided part of the theoretical motivation for our work. Although there is almost no support from the many experiments motivated by the EPF data for a fifth force with properties similar to those that we hypothesized in our original paper, interest in the EPF experiment continues for reasons I outline in the Epilogue.
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Eutectic melting temperature of the lowermost Earth's mantle
Andrault, D.; Lo Nigro, G.; Bolfan-Casanova, N.; Bouhifd, M.; Garbarino, G.; Mezouar, M.
2009-12-01
Partial melting of the Earth's deep mantle probably occurred at different stages of its formation as a consequence of meteoritic impacts and seismology suggests that it even continues today at the core-mantle boundary. Melts are important because they dominate the chemical evolution of the different Earth's reservoirs and more generally the dynamics of the whole planet. Unfortunately, the most critical parameter, that is the temperature profile inside the deep Earth, remains poorly constrained accross the planet history. Experimental investigations of the melting properties of materials representative of the deep Earth at relevant P-T conditions can provide anchor points to refine past and present temperature profiles and consequently determine the degree of melting at the different geological periods. Previous works report melting relations in the uppermost lower mantle region, using the multi-anvil press [1,2]. On the other hand, the pyrolite solidus was determined up to 65 GPa using optical observations in the laser-heated diamond anvil cell (LH-DAC) [3]. Finally, the melting temperature of (Mg,Fe)2SiO4 olivine is documented at core-mantle boundary (CMB) conditions by shock wave experiments [4]. Solely based on these reports, experimental data remain too sparse to draw a definite melting curve for the lower mantle in the relevant 25-135 GPa pressure range. We reinvestigated melting properties of lower mantle materials by means of in-situ angle dispersive X-ray diffraction measurements in the LH-DAC at the ESRF [5]. Experiments were performed in an extended P-T range for two starting materials: forsterite and a glass with chondrite composition. In both cases, the aim was to determine the onset of melting, and thus the eutectic melting temperatures as a function of pressure. Melting was evidenced from drastic changes of diffraction peak shape on the image plate, major changes in diffraction intensities in the integrated pattern, disappearance of diffraction rings
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Taking Spectacle Seriously: Wildlife Film and the Legacy of Natural History Display.
Louson, Eleanor
2018-03-01
Argument I argue through an analysis of spectacle that the relationship between wildlife documentary films' entertainment and educational mandates is complex and co-constitutive. Accuracy-based criticism of wildlife films reveals assumptions of a deficit model of science communication and positions spectacle as an external commercial pressure influencing the genre. Using the Planet Earth (2006) series as a case study, I describe spectacle's prominence within the recent blue-chip renaissance in wildlife film, resulting from technological innovations and twenty-first-century consumer and broadcast market contexts. I connect spectacle in contemporary wildlife films to its relevant precursors within natural history, situating spectacle as a central feature of natural history display designed to inspire awe and wonder in audiences. I show that contemporary documentary spectacle is best understood as an opportunity for affective knowing rather than a constraint on accuracy; as a result, spectacle contributes to the virtuous inter-reinforcement of entertainment and education at work in blue-chip wildlife films.
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Geohistory. Global evolution of the earth
Energy Technology Data Exchange (ETDEWEB)
Ozima, Minoru
1987-01-01
A full understanding of the earth's evolution can be achieved only by considering it as a continuous process starting with the birth of the solar system. This book traces the evolution of the earth, mainly on the basis of radiogenic isotopes from long half-life parent elements, and discusses it in terms of the latest developments in astrophysical theory, which impose unique constraints on the earth's origin and early evolution. By its 'historical' nature, geohistorical study also offers a unique approach to forecasting the future of the earth, yielding useful clues for the understanding of environmental problems, such as radioactive waste disposal. This book aims to provide an outline of global evolution of the planet earth for students of general science and for earth scientists.
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What can earth tide measurements tell us about ocean tides or earth structure?
Baker, T. F.
1978-01-01
Current experimental problems in Earth tides are reviewed using comparisons of tidal gravity and tilt measurements in Europe with loading calculations are examples. The limitations of present day instrumentation and installation techniques are shown as well as some of the ways in which they can be improved. Many of the geophysical and oceanographic investigations that are possible with Earth tide measurements are discussed with emphasis on the percentage accuracies required in the measurements in order to obtain new information about Earth or its oceans.
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Indian Academy of Sciences (India)
Table of contents. EARTH FROM SPACE · Slide 2 · Earth System · Slide 4 · Global water cycle · Slide 6 · Slide 7 · Direct Observations of Recent Climate Change · Slide 9 · Slide 10 · Snow cover and Arctic sea ice are decreasing · Polar Melting & Global Heat Transport · Antarctica: Melting and Thickening · Slide 14 · Slide 15.
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Nelson, P A; Powers, J N; Estridge, T D; Elder, E A; Alea, A D; Sidhu, P K; Sehl, L C; DeLustro, F A
2001-01-01
A randomized, controlled clinical study of the management of diffuse bleeding with CoStasis surgical hemostat, a new hemostat containing bovine thrombin and collagen with the patient's own plasma, included patients undergoing cardiac, hepatic, iliac, and general surgery. Sera from 92 patients treated with CoStasis and 84 control patients were collected preoperatively and at a post surgical follow-up of 8 weeks. Among the control group, 57 patients were treated with Instat collagen sponge in noncardiac indications. Results showed that antibody responses in the CoStasis clinical study were similar to the reported literature for all antigens screened and were not associated with any adverse reactions. The bovine thrombin preparations in CoStasis and other commercially available thrombins were compared with the use of SDS-PAGE and Western blot analyses. Within this clinical study, CoStasis was shown to be a safe and effective hemostatic product containing bovine thrombin and bovine collagen and no pooled human blood products. Copyright 2001 John Wiley & Sons, Inc.
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Cashman, K. V.; Rust, A.; Stibbon, E.; Harris, R.
2016-12-01
Earth materials are fundamental to art. They are pigments, they are clay, they provide form and color. Earth scientists, however, rarely attempt to make the physical properties of Earth materials visible through art, and similarly many artists use Earth materials without fully understanding their physical and chemical properties. Here we explore the intersection between art and science through study of the physical properties of Earth materials as characterized in the laboratory, and as transferred to paper using different techniques and suspending media. One focus of this collaboration is volcanic ash. Ash is interesting scientifically because its form provides information on the fundamental processes that drive volcanic eruptions, and determines its transport properties, and thus its potential to affect populations far downwind of the volcano. Ash properties also affect its behavior as an art material. From an aesthetic point of view, ash lends a granular surface to the image; it is also uncontrollable, and thus requires engagement between artist and medium. More fundamentally, using ash in art creates an exchange between the medium and the subject matter, and imparts something of the physical, visceral experience of volcanic landscapes to the viewer. Another component of this work uses powdered rock as a printing medium for geologic maps. Because different types of rock create powders with different properties (grain size distributions and shapes), the geology is communicated not only as color, but also by the physical characteristics of the material as it interacts with the paper. More importantly, the use of actual rocks samples as printing material for geologic maps not only makes a direct connection between the map and the material it represents, but also provides an emotional connection between the map, the viewer and the landscape, its colors, textures and geological juxtapositions. Both case studies provide examples not only of ways in which artists can
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International Nuclear Information System (INIS)
Burch, Aidan
2004-01-01
Working within the HPO (History Projection Operator) Consistent Histories formalism, we follow the work of Savvidou on (scalar) field theory [J. Math. Phys. 43, 3053 (2002)] and that of Savvidou and Anastopoulos on (first-class) constrained systems [Class. Quantum Gravt. 17, 2463 (2000)] to write a histories theory (both classical and quantum) of Electromagnetism. We focus particularly on the foliation-dependence of the histories phase space/Hilbert space and the action thereon of the two Poincare groups that arise in histories field theory. We quantize in the spirit of the Dirac scheme for constrained systems
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Nisbet, E. G.; Fowler, C. M. R.
2003-12-01
ago, for the most part the planet was peaceful. Even the most active volcanoes are mostly quiet; meteorites large enough to extinguish all dinosaurs may have hit as often as every few thousand years, but this is not enough to be a nuisance to a bacterium (except when the impact boiled the ocean); while to the photosynthesizer long-term shifts in the solar spectrum may be less of a problem than cloudy hazy days. Though, admittedly, green is junk light to biology, the excretion from the photosynthetic antennae, nevertheless even a green sky would have had other wavelengths also in its spectrum.Most important of all, like all good houses, this planet had location: Earth was just in the right spot. Not too far from the faint young Sun (Sagan and Chyba, 1997), it was also far enough away still to be in the comfort zone ( Kasting et al., 1993) when the mature Sun brightened. As many have pointed out, when Goldilocks arrived, she found everything just right. But what is less obvious is that as she grew and changed, and the room changed too, she commenced to rearrange the furniture to make it ever righter for her. Thus far, the bears have not arrived, though they may have reclaimed Mars from Goldilocks's sister see ( Figure 1). (3K)Figure 1. The habitable zone (Kasting et al., 1993). Too close to the Sun, a planet's surface is too hot to be habitable; too far, it is too cold. Early in the history of the solar system, the Sun was faint and the habitable zone was relatively close; 4.5 Ga later, with a brighter Sun, planets formerly habitable are now too hot, and the habitable zone has shifted out. Note that boundaries can shift. By changing its albedo and by altering the greenhouse gas content of the air, the planet can significantly widen the bounds of the habitable zone (Lovelock, 1979, 1988).
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Connors, Martin; Wiegert, Paul; Veillet, Christian
2011-07-27
It was realized in 1772 that small bodies can stably share the same orbit as a planet if they remain near 'triangular points' 60° ahead of or behind it in the orbit. Such 'Trojan asteroids' have been found co-orbiting with Jupiter, Mars and Neptune. They have not hitherto been found associated with Earth, where the viewing geometry poses difficulties for their detection, although other kinds of co-orbital asteroid (horseshoe orbiters and quasi-satellites) have been observed. Here we report an archival search of infrared data for possible Earth Trojans, producing the candidate 2010 TK(7). We subsequently made optical observations which established that 2010 TK(7) is a Trojan companion of Earth, librating around the leading Lagrange triangular point, L(4). Its orbit is stable over at least ten thousand years.
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The climatic and hydrologic history of southern Nevada during the late Quaternary
International Nuclear Information System (INIS)
Forester, R.M.; Bradbury, J.P.; Carter, C.; Elvidge-Tuma, A.B.; Hemphill, M.L.; Lundstrom, S.C.; Mahan, S.A.; Marshall, B.D.; Neymark, L.A.; Paces, J.B.; Sharpe, S.E.; Whelan, J.F.; Wigand, P.E.
1999-01-01
Understanding climate change during the expected life span of a potential high-level nuclear-waste repository at Yucca Mountain, Nevada, requires estimates of future climate boundary conditions. These climate boundary conditions are governed by changes in the Earth's orbital properties (eccentricity, obliquity, precession) that determine insolation. Subcycles of the 400,000 year insolation-controlled climate cycles last approximately 100,000 years. This report describes the changes which have occurred in the climatic history of Southern Nevada during the past 400,000 years. These changes provide a basis for understanding the changes which may occur during the long-term future in this area
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Assessing the Impact of Earth Radiation Pressure Acceleration on Low-Earth Orbit Satellites
Vielberg, Kristin; Forootan, Ehsan; Lück, Christina; Kusche, Jürgen; Börger, Klaus
2017-04-01
The orbits of satellites are influenced by several external forces. The main non-gravitational forces besides thermospheric drag, acting on the surface of satellites, are accelerations due to the Earth and Solar Radiation Pres- sure (SRP and ERP, respectively). The sun radiates visible and infrared light reaching the satellite directly, which causes the SRP. Earth also emits and reflects the sunlight back into space, where it acts on satellites. This is known as ERP acceleration. The influence of ERP increases with decreasing distance to the Earth, and for low-earth orbit (LEO) satellites ERP must be taken into account in orbit and gravity computations. Estimating acceler- ations requires knowledge about energy emitted from the Earth, which can be derived from satellite remote sensing data, and also by considering the shape and surface material of a satellite. In this sensitivity study, we assess ERP accelerations based on different input albedo and emission fields and their modelling for the satellite missions Challenging Mini-Satellite Payload (CHAMP) and Gravity Recovery and Climate Experiment (GRACE). As input fields, monthly 1°x1° products of Clouds and the Earth's Radiant En- ergy System (CERES), L3 are considered. Albedo and emission models are generated as latitude-dependent, as well as in terms of spherical harmonics. The impact of different albedo and emission models as well as the macro model and the altitude of satellites on ERP accelerations will be discussed.
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HABEBEE: habitability of eyeball-exo-Earths.
Angerhausen, Daniel; Sapers, Haley; Citron, Robert; Bergantini, Alexandre; Lutz, Stefanie; Queiroz, Luciano Lopes; da Rosa Alexandre, Marcelo; Araujo, Ana Carolina Vieira
2013-03-01
Extrasolar Earth and super-Earth planets orbiting within the habitable zone of M dwarf host stars may play a significant role in the discovery of habitable environments beyond Earth. Spectroscopic characterization of these exoplanets with respect to habitability requires the determination of habitability parameters with respect to remote sensing. The habitable zone of dwarf stars is located in close proximity to the host star, such that exoplanets orbiting within this zone will likely be tidally locked. On terrestrial planets with an icy shell, this may produce a liquid water ocean at the substellar point, one particular "Eyeball Earth" state. In this research proposal, HABEBEE: exploring the HABitability of Eyeball-Exo-Earths, we define the parameters necessary to achieve a stable icy Eyeball Earth capable of supporting life. Astronomical and geochemical research will define parameters needed to simulate potentially habitable environments on an icy Eyeball Earth planet. Biological requirements will be based on detailed studies of microbial communities within Earth analog environments. Using the interdisciplinary results of both the physical and biological teams, we will set up a simulation chamber to expose a cold- and UV-tolerant microbial community to the theoretically derived Eyeball Earth climate states, simulating the composition, atmosphere, physical parameters, and stellar irradiation. Combining the results of both studies will enable us to derive observable parameters as well as target decision guidance and feasibility analysis for upcoming astronomical platforms.
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Pull vs. Push: How OmniEarth Delivers Better Earth Observation Information to Subscribers
Fish, C.; Slagowski, S.; Dyrud, L.; Fentzke, J.; Hargis, B.; Steerman, M.
2015-04-01
Until very recently, the commercialization of Earth observation systems has largely occurred in two ways: either through the detuning of government satellites or the repurposing of NASA (or other science) data for commercial use. However, the convergence of cloud computing and low-cost satellites is enabling Earth observation companies to tailor observation data to specific markets. Now, underserved constituencies, such as agriculture and energy, can tap into Earth observation data that is provided at a cadence, resolution and cost that can have a real impact to their bottom line. To connect with these markets, OmniEarth fuses data from a variety of sources, synthesizes it into useful and valuable business information, and delivers it to customers via web or mobile interfaces. The "secret sauce" is no longer about having the highest resolution imagery, but rather it is about using that imagery - in conjunction with a number of other sources - to solve complex problems that require timely and contextual information about our dynamic and changing planet. OmniEarth improves subscribers' ability to visualize the world around them by enhancing their ability to see, analyze, and react to change in real time through a solutions-as-a-service platform.
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Technology-Induced Risks in History
Rabkin, Ya.
Our perception of risk contains three main aspects: (1) probability of the risk occurring; (2) the extent of possible damage; (3) the degree of voluntary or involuntary exposure to risk. History of risk assessment has been traced in several areas, such as transportation, and has largely focused on insurance. Construction projects constitute one of the oldest areas of technology where accidents continue to occur, while health has always been a fragile commodity. Urbanization has multiplied the risks of illness and death, while natural catastrophes, though still frightening, have ceded their central place to technology-based disasters in the Western perceptions of risk. The human has become the main source of danger to the very survival of the planet. The Enlightenment utopia of scientific progress resulting in social and moral progress of humanity has collided with the awareness of new technology induced risks. Life on Earth began without humans, and it may end without them. Our civilization is the first that faces an end to be brought about by our own technological ingenuity.
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Huss, G. R.; Alexander, E. C., Jr.
1985-01-01
The development of models as tracers of nobel gases through the Earth's evolution is discussed. A new set of paradigms embodying present knowledge was developed. Several important areas for future research are: (1) measurement of the elemental and isotopic compositions of the five noble gases in a large number of terrestrial materials, thus better defining the composition and distribution of terrestrial noble gases; (2) determinations of relative diffusive behavior, chemical behavior, and the distribution between solid and melt of noble gases under mantle conditions are urgently needed; (3) disequilibrium behavior in the nebula needs investigation, and the behavior of plasmas and possible cryotrapping on cold nebular solids are considered.