WorldWideScience

Sample records for total earth stress

  1. Probing Earth's State of Stress

    Science.gov (United States)

    Delorey, A. A.; Maceira, M.; Johnson, P. A.; Coblentz, D. D.

    2016-12-01

    The state of stress in the Earth's crust is a fundamental physical property that controls both engineered and natural systems. Engineered environments including those for hydrocarbon, geothermal energy, and mineral extraction, as well those for storage of wastewater, carbon dioxide, and nuclear fuel are as important as ever to our economy and environment. Yet, it is at spatial scales relevant to these activities where stress is least understood. Additionally, in engineered environments the rate of change in the stress field can be much higher than that of natural systems. In order to use subsurface resources more safely and effectively, we need to understand stress at the relevant temporal and spatial scales. We will present our latest results characterizing the state of stress in the Earth at scales relevant to engineered environments. Two important components of the state of stress are the orientation and magnitude of the stress tensor, and a measure of how close faults are to failure. The stress tensor at any point in a reservoir or repository has contributions from both far-field tectonic stress and local density heterogeneity. We jointly invert seismic (body and surface waves) and gravity data for a self-consistent model of elastic moduli and density and use the model to calculate the contribution of local heterogeneity to the total stress field. We then combine local and plate-scale contributions, using local indicators for calibration and ground-truth. In addition, we will present results from an analysis of the quantity and pattern of microseismicity as an indicator of critically stressed faults. Faults are triggered by transient stresses only when critically stressed (near failure). We show that tidal stresses can trigger earthquakes in both tectonic and reservoir environments and can reveal both stress and poroelastic conditions.

  2. Induced groundwater flux by increases in the aquifer's total stress.

    Science.gov (United States)

    Chang, Ching-Min; Yeh, Hund-Der

    2015-01-01

    Fluid-filled granular soils experience changes in total stress because of earth and oceanic tides, earthquakes, erosion, sedimentation, and changes in atmospheric pressure. The pore volume may deform in response to the changes in stress and this may lead to changes in pore fluid pressure. The transient fluid flow can therefore be induced by the gradient in excess pressure in a fluid-saturated porous medium. This work demonstrates the use of stochastic methodology in prediction of induced one-dimensional field-scale groundwater flow through a heterogeneous aquifer. A closed-form of mean groundwater flux is developed to quantify the induced field-scale mean behavior of groundwater flow and analyze the impacts of the spatial correlation length scale of log hydraulic conductivity and the pore compressibility. The findings provided here could be useful for the rational planning and management of groundwater resources in aquifers that contain lenses with large vertical aquifer matrix compressibility values. © 2014, National Ground Water Association.

  3. Total-dose hardness assurance for low earth orbit

    International Nuclear Information System (INIS)

    Maurer, R.H.; Suter, J.J.

    1987-01-01

    The Low Earth Orbit radiation environment has two significant characteristics that make laboratory simulation exposures difficult: (1) a low dose rate and (2) many cycles of low dose accumulation followed by dose-free annealing. Hardness assurance considerations for this environment are discussed and related to data from the testing of Advanced Low Power Schottky and High-speed CMOS devices

  4. Decreased total antioxidant levels and increased oxidative stress in ...

    African Journals Online (AJOL)

    21–25 ... Decreased total antioxidant levels and increased oxidative stress in South ... antioxidant-rich diet and lifestyle changes in T2DM patients would help to avert the .... glycation of proteins and the formation of advanced glycosylation.

  5. Decreased total antioxidant levels and increased oxidative stress in ...

    African Journals Online (AJOL)

    Background: Chronic hyperglycaemia in diabetes mellitus leads to increased lipid peroxidation in the body, followed by the development of chronic complications due to oxidative stress. Objective: The aim of this study was to compare total antioxidant (TAO) levels and oxidative stress in type 2 diabetes mellitus (T2DM) ...

  6. To Measure Probable Physical Changes On The Earth During Total Solar Eclipse Using Geophysical Methods

    International Nuclear Information System (INIS)

    Gocmen, C.

    2007-01-01

    When the total solar eclipse came into question, people connected the eclipse with the earthquake dated 17.08.1999. We thought if any physical parameters change during total solar eclipse on the earth, we could measure this changing and we did the project 'To Measure Probable Physical Changes On The Earth During Total Solar Eclipse Using Geophysical Methods' We did gravity, magnetic and self-potential measurements at Konya and Ankara during total solar eclipse (29, March, 2006) and the day before eclipse and the day after eclipse. The measurements went on three days continuously twenty-four hours at Konya and daytime in Ankara. Bogazici University Kandilli Observatory gave us magnetic values in Istanbul and we compare the values with our magnetic values. Turkish State Meteorological Service sent us temperature and air pressure observations during three days, in Konya and Ankara. We interpreted all of them

  7. High performance thermal stress analysis on the earth simulator

    International Nuclear Information System (INIS)

    Noriyuki, Kushida; Hiroshi, Okuda; Genki, Yagawa

    2003-01-01

    In this study, the thermal stress finite element analysis code optimized for the earth simulator was developed. A processor node of which of the earth simulator is the 8-way vector processor, and each processor can communicate using the message passing interface. Thus, there are two ways to parallelize the finite element method on the earth simulator. The first method is to assign one processor for one sub-domain, and the second method is to assign one node (=8 processors) for one sub-domain considering the shared memory type parallelization. Considering that the preconditioned conjugate gradient (PCG) method, which is one of the suitable linear equation solvers for the large-scale parallel finite element methods, shows the better convergence behavior if the number of domains is the smaller, we have determined to employ PCG and the hybrid parallelization, which is based on the shared and distributed memory type parallelization. It has been said that it is hard to obtain the good parallel or vector performance, since the finite element method is based on unstructured grids. In such situation, the reordering is inevitable to improve the computational performance [2]. In this study, we used three reordering methods, i.e. Reverse Cuthil-McKee (RCM), cyclic multicolor (CM) and diagonal jagged descending storage (DJDS)[3]. RCM provides the good convergence of the incomplete lower-upper (ILU) PCG, but causes the load imbalance. On the other hand, CM provides the good load balance, but worsens the convergence of ILU PCG if the vector length is so long. Therefore, we used the combined-method of RCM and CM. DJDS is the method to store the sparse matrices such that longer vector length can be obtained. For attaining the efficient inter-node parallelization, such partitioning methods as the recursive coordinate bisection (RCM) or MeTIS have been used. Computational performance of the practical large-scale engineering problems will be shown at the meeting. (author)

  8. A study on the separation method of total rare earth oxides in Xenotime

    International Nuclear Information System (INIS)

    Shim, Sang Kwon; Park, Hea Kyung; Kim, Kyung Lim

    1990-01-01

    This study is concerned with the separation method of total rare earth oxides in Xenotime by acid digest method. Thioacetamide was used as a carrier, tartaric acid was used as a masking agent and oxalic acid was used as a precipitant. So the effects of three acid digest methods, pH of the solution, digesting time,tartaric acid, oxalic acid and aging time were oberved. The results showed that the best acid digest method was sulfuric acid leaching and mixed acid digest method, and that pH of the solution was 2, digesting time was 4 hours, tartaric acid was 100 ml of 2% solution, oxalic acid was 8 gr. and aging time was 1 hour. Through this experiment, it was confirmed by X-ray diffractometer that the separated total rare earth oxides consisted of the Yttrium and the other rare earth elements : Gadolinium, Dysprosium, Erbium, Ytterbium and trace rare earth elements. The pure rare earth oxides being separated by this method were dried and ignited at 900 deg C (Author)

  9. Transmission and total reflection of subhertz electromagnetic waves at the earth-atmosphere interface

    International Nuclear Information System (INIS)

    Shiozawa, Toshiyuki

    2010-01-01

    For the purpose of providing for a theoretical background for the study of electromagnetic fields generated by precursory effects of earthquakes, the problem of transmission and total reflection at the earth-atmosphere interface is investigated in detail for a subhertz plane electromagnetic wave incident from the earth's crust. The term ''subhertz'' means 'below 1 Hz'. First, for the special case of normal incidence, the overall power transmission coefficient at the earth-atmosphere interface is found to take a maximum value at a definite frequency f 0 which is inversely proportional to the square of the depth of a virtual hypocenter. A typical value of f 0 falls around 0.01 Hz. For oblique incidence as well, this feature of the overall power transmission coefficient is retained except in the vicinity of the critical angle of incidence for the H-wave. At the critical angle of incidence, the power flow carried by a surface wave along the interface becomes anomalously large for the H-wave. However, over a wide range of angles of incidence greater than the critical angle, the power flow carried by the E-wave exceeds that carried by the H-wave by orders of magnitude. Finally, the energy conservation relations for the incident, reflected, and transmitted waves at the earth-atmosphere interface are discussed. For an incident wave coming from the earth's crust, the interactive power between the incident and reflected waves plays a crucial role for the conservation of energy at the interface.

  10. [Seasonal changes and response to stress of total flavonoids content of Farfugium japonicum].

    Science.gov (United States)

    Cui, Dalian; Ma, Yuxin

    2013-05-01

    To investigate the seasonal variation of total flavonoid content of Farfugium japonicum and its response to stress. The total flavonoids of Farfugium japonicum were determined by spectrophotometry in different seasons and under various stressful factors. The total flavonoid content in Farfugium japonicum leaves was the highest, followed by the petiole, and rhizomes (Pseasons (Pwater stress, the total flavonoid content in Farfugium japonicum leaves gradually increased, that in petiole first increased and then decreased,while that in rhizomes decreased (Pstress, the total flavonoid content in leaves, petioles and rhizomes of Farfugium japonicum showed a decreasing trend (Pseasons and that in different parts of the plant has different responses to ecological stressful factors.

  11. Performance Study of Earth Networks Total Lightning Network using Rocket-Triggered Lightning Data in 2014

    Science.gov (United States)

    Heckman, S.

    2015-12-01

    Modern lightning locating systems (LLS) provide real-time monitoring and early warning of lightningactivities. In addition, LLS provide valuable data for statistical analysis in lightning research. It isimportant to know the performance of such LLS. In the present study, the performance of the EarthNetworks Total Lightning Network (ENTLN) is studied using rocket-triggered lightning data acquired atthe International Center for Lightning Research and Testing (ICLRT), Camp Blanding, Florida.In the present study, 18 flashes triggered at ICLRT in 2014 were analyzed and they comprise of 78negative cloud-to-ground return strokes. The geometric mean, median, minimum, and maximum for thepeak currents of the 78 return strokes are 13.4 kA, 13.6 kA, 3.7 kA, and 38.4 kA, respectively. The peakcurrents represent typical subsequent return strokes in natural cloud-to-ground lightning.Earth Networks has developed a new data processor to improve the performance of their network. Inthis study, results are presented for the ENTLN data using the old processor (originally reported in 2014)and the ENTLN data simulated using the new processor. The flash detection efficiency, stroke detectionefficiency, percentage of misclassification, median location error, median peak current estimation error,and median absolute peak current estimation error for the originally reported data from old processorare 100%, 94%, 49%, 271 m, 5%, and 13%, respectively, and those for the simulated data using the newprocessor are 100%, 99%, 9%, 280 m, 11%, and 15%, respectively. The use of new processor resulted inhigher stroke detection efficiency and lower percentage of misclassification. It is worth noting that theslight differences in median location error, median peak current estimation error, and median absolutepeak current estimation error for the two processors are due to the fact that the new processordetected more number of return strokes than the old processor.

  12. Millennial total sea-level commitments projected with the Earth system model of intermediate complexity LOVECLIM

    International Nuclear Information System (INIS)

    Goelzer, H; Huybrechts, P; Raper, S C B; Loutre, M-F; Goosse, H; Fichefet, T

    2012-01-01

    Sea-level is expected to rise for a long time to come, even after stabilization of human-induced climatic warming. Here we use simulations with the Earth system model of intermediate complexity LOVECLIM to project sea-level changes over the third millennium forced with atmospheric greenhouse gas concentrations that stabilize by either 2000 or 2100 AD. The model includes 3D thermomechanical models of the Greenland and Antarctic ice sheets coupled to an atmosphere and an ocean model, a global glacier melt algorithm to account for the response of mountain glaciers and ice caps, and a procedure for assessing oceanic thermal expansion from oceanic heat uptake. Four climate change scenarios are considered to determine sea-level commitments. These assume a 21st century increase in greenhouse gases according to SRES scenarios B1, A1B and A2 with a stabilization of the atmospheric composition after the year 2100. One additional scenario assumes 1000 years of constant atmospheric composition from the year 2000 onwards. For our preferred model version, we find an already committed total sea-level rise of 1.1 m by 3000 AD. In experiments with greenhouse gas concentration stabilization at 2100 AD, the total sea-level rise ranges between 2.1 m (B1), 4.1 m (A1B) and 6.8 m (A2). In all scenarios, more than half of this amount arises from the Greenland ice sheet, thermal expansion is the second largest contributor, and the contribution of glaciers and ice caps is small as it is limited by the available ice volume of maximally 25 cm of sea-level equivalent. Additionally, we analysed the sensitivity of the sea-level contributions from an ensemble of nine different model versions that cover a large range of climate sensitivity realized by model parameter variations of the atmosphere–ocean model. Selected temperature indices are found to be good predictors for sea-level contributions from the different components of land ice and oceanic thermal expansion after 1000 years. (letter)

  13. Methods of Separation of Total Rare Earths in Low-Alloy Constructional Steels

    Science.gov (United States)

    1954-11-10

    investigation of the effects of added anions upon the absorption spectra of the rare earths elements has been continued. The effects of tartrate in...complexes, the equilibrium among the di-hydrogen cupric EDTA complex, uncomplexed cupric ions, the monohydrogen rare earth- EDTA complex and rare...solutions used are described. A polaro- graphic method for determining cupric ion concentration in support- ing KNOj solutions, and thereby supporting

  14. The effect of acid rain stress on chlorophyll, peroxidase of the conservation of rare earth elements

    International Nuclear Information System (INIS)

    Chongling, Y.; Yetang, H.; Xianke, Y.; Shunzhen, F.; Shanql, W.

    1998-01-01

    Full text: Based on pot experiment, the effect of acid rain stress on chlorophyll, peroxidase of wheat, the relationship of them and the conservation of rare earth elements has been studied. The result showed: stress of acid rain resulted in decrease of chlorophyll content and a/b values, chlorophyll a/b value and chlorophyll content is positive correlation with pH value of acid rain: peroxidase activity was gradually rise with pH value decrease, which indirectly increased decomposition intensity of chlorophyll. Decreased content and a/b value of chlorophyll further speeded blade decay affected the transport and transformation of light energy and metabolism of carbohydrates. After being treated by rare earth elements content and pH value of chlorophyll and peroxidase activity could be relatively stable. Therefore, under lower acidity condition, rare earth elements can influence the effect of acid rain on chlorophyll and peroxidase activity of wheat

  15. Study on recovering directly the commercial cerium oxide and total of residue rare earths from Dongpao bastnasite concentrate

    International Nuclear Information System (INIS)

    Nguyen Trong Hung; Nguyen Thanh Chung; Luu Xuan Dinh

    2003-01-01

    A technology for decomposition roasting and sequential leaching processes of Dong Pao bastnasite concentrate to recover directly commercial cerium oxide and total of residue rare earth elements from the leaching solution of the roasted product have been investigated. The bastnasite concentrate is initially roasted at temperature range of 600 - 650 degC and for time of 4 hrs in order to decompose and convert the hardly soluble carbonate forms of ore into easily soluble oxide. The roasted solid is then leached with sulfuric acid solution of 6N at 60 degC for 4 hrs to convert rare earths in oxide and fluoride form into rare earth sulfate. The recovery yield of rare earths of these stages is more than 95%. The attention has especially been paid on recovering directly the commercial cerium oxide and total of residue rare earth element from the above leaching solution. Complex ions of CeSO 4 2+ , Ce(SO 4 ) 2 , Ce(SO 4 ) 3 2- and Ce(SO 4 ) 4 4- exist in aqueous solution of cerium (IV) sulfate. Based on the property, the method of ion - sieve with DOWEX cation resin column has been applied to estimating separation of the ceric complex anions from Ln(III). The survey showed that most of the ceric complex anions are separated from total of residue rare earths. The latter which are absorbed in the cation column are recovered by elution of HCl of 4N. The recovery yield of cerium can only be reached 20% but the purity of that is very high, can be reached 99.6%. About 5 kg of CeO 2 of high grade and 5 kg of TREO of commercial specification have been produced. (author)

  16. Research on manufacturing aluminum - rare earth alloy with a high content of rare earth (> 20% RE) from total rare earth oxides by thermit reduction

    International Nuclear Information System (INIS)

    Ngo Trong Hiep; Dam Van Tien; Tran Duy Hai; Ngo Xuan Hung and Ly Thanh Vu

    2004-01-01

    In this report, several theoretical principles of thermit reduction method used for metal oxides to obtain metals, ferroalloys and ligatua with technical purity are presented. Manufacture of aluminum-rare earth alloys by thermit reduction is also described in the report. Data that are generalized based on thermo-kinetic calculation of the thermit reduction and selection of technological flow-sheet based on thermal effect will partly clarify research results in investigating typical features of the process and identify measures to reduce metal loss in discharged slags. (author)

  17. Mitigation method of thermal transient stress by thermalhydraulic-structure total analysis

    International Nuclear Information System (INIS)

    Kasahara, Naoto; Jinbo, Masakazu; Hosogai, Hiromi

    2003-01-01

    This study proposes a rational evaluation and mitigation method of thermal transient loads in fast reactor components by utilizing relationships among plant system parameters and stresses induced by thermal transients of plants. A thermalhydraulic-structure total analysis procedure helps us to grasp relationship among system parameters and thermal stresses. Furthermore, it enables mitigation of thermal transient loads by adjusting system parameters. In order to overcome huge computations, a thermalhydraulic-structure total analysis code and the Design of Experiments methodology are utilized. The efficiency of the proposed mitigation method is validated through thermal stress evaluation of an intermediate heat exchanger in Japanese demonstration fast reactor. (author)

  18. Tibiofemoral contact stress and stress distribution evaluation of total knee arthroplasties.

    Science.gov (United States)

    Szivek, J A; Cutignola, L; Volz, R G

    1995-08-01

    The Fuji film (Itochu, Los Angeles, CA) area analysis technique demonstrates that a more accurate assessment of tibiofemoral contact stresses is possible when the film is used at 37 degrees C and at the upper end of its sensitivity range (in this case, a 2,000-N load). An AMK with a regular and Hylamer-M insert (DePuy, Warsaw, IN), an MG II (Zimmer, Warsaw, IN), an Omnifit (Osteonics, Allendale, NJ), an Ortholoc III (Dow Corning Wright, Midland, MI), a PCA II (Howmedica, Rutherford, NJ), and a PFC (Johnson & Johnson Orthopaedics, Raynham, MA) had average contact stresses that varied only 12% at 60 degrees flexion. At 0 degrees, 15 degrees and 60 degrees flexion, stresses ranged from 13 to 25 MPa. Contact area distribution ratios, which were smaller at 37 degrees C than at 24 degrees C, provide a quantitative means of grouping implants according to the shape of the tibiofemoral contact area. The Omnifit, MG II, PCA II, and PFC had small ratios (symmetric areas). The AMK and Ortholoc III had large ratios (asymmetric contact areas). If the impression is reflective of wear, it would be expected to be focal in knees with small ratios and contact areas, and uniform in knees with large ratios and contact areas, whereas large ratios and small areas would imply a linear wear pattern. Calibrated electrical resistance contact stress measurements indicated that the Fuji film measurements underestimated the magnitude of contact stresses. They also provided a means of quantifying the rate of area increase during initial loading of the knees, with the highest area increase noted for the knee with the roughest insert (Ortholoc III) and the lowest area increase for the knee with the smoothest insert (PCA II).

  19. Influence of oxidative stress on the development of collateral circulation in total coronary occlusions.

    Science.gov (United States)

    Demirbag, Recep; Gur, Mustafa; Yilmaz, Remzi; Kunt, Alper Sami; Erel, Ozcan; Andac, M Halit

    2007-03-02

    The purpose of this study was to investigate whether the levels of total antioxidant capacity (TAC), total peroxide and oxidative stress index (OSI) are associated with the development of collaterals in total coronary occlusions. Our study group contained 176 consecutive men patients with single-vessel TCO, 94 of whom had poorly developed coronary collateral, while 82 had well-developed coronary collateral. TAC and total peroxide concentration were measured of plasma. The ratio of TAC to total peroxide was accepted as an indicator of oxidative stress. The values of total peroxide and OSI in the Group I were significantly lower than that in Group II (ptotal peroxide and OSI levels (ptotal peroxide and OSI were independent predictors of collaterals score (p=0.006 and ptotal coronary occlusion patients.

  20. Earth

    CERN Document Server

    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

  1. Coping strategies related to total stress score among post graduate medical students and residents

    Directory of Open Access Journals (Sweden)

    R. Irawati Ismail

    2013-05-01

    Full Text Available AbstrakLatar belakang:Beberapa strategi penanganan yang dapat mengurangi tingkat stres. Tujuan penelitian ini untuk mengidentifikasi beberapa strategi yang dominan terhadap tingkat skor stres total.Metode:Pada penelitian potong lintang dengan sampel purposif mahasiswa kedokteran pasca sarjana Fakultas Kedokteran Universitas Indonesia pada bulan April-Juli 2011. Kuesioner yang digunakan ialah kuesioner strategi mengurangi stres dan self reporting questionnaire WHO (SRQ-20. Regresi liniar digunakan Untuk mengidentifikasi faktor dominan terhadap tingkat stres dipergunakan regresi linear.Hasil: Subjek terdiri dari 272 orang, usia 23-44 tahun. Empat hal menurunkan skor stres total (menerima realitas, berbicara dengan seseorang yang dapat melakukan sesuatu, meminta bantuan Allah, dan menertawakan situasi yang bermasalah. Sebaiknya tiga faktor meningkatkan skor stres total (menyelesaikan langkah demi langkah pada suatu waktu, berbicara dengan seseorang untuk mengetahui lebih lanjut tentang situasi, dan mengakui tidak bisa menangani pemecahan situasi. Satu poin menerima realitas situasi mengurangi 0,493 poin skor total stress [koefisien regresi (β = -0,493, P = 0,002]. Sementara satu poin mencari pertolongan Allah akan mengurangi 0,307 poin skor stres total (β = -0,307, P = 0,056. Namun, satu poin melakukan satu langkah pada suatu waktu akan meningkatkan 0,54 poin skor stres total (β = 0,540, P = 0,005.Kesimpulan: Menerima realitas, berbicara dengan seseorang yang dapat melakukan sesuatu, meminta bantuan Allah, dan menertawakan situasi akan menurunkan tingkat stres. Sebaiknya, menyelesaikan langkah demi langkah pada suatu waktu, berbicara dengan seseorang untuk mengetahui lebih lanjut tentang situasi, dan mengakui tidak bisa menangani memecahkan situasi, meningkatkan skor stres total.Kata kunci:strategi pengendalan stres, meminta pertolongan AlllahAbstractBackground:Several coping strategies may minimize stress levels. This study aimed to identify

  2. TO DETERMINATION OF DAMPING COEFFICIENT OF VERTICAL DEAD STRESS OF EARTH DAMS ON A DEPTH

    Directory of Open Access Journals (Sweden)

    NESTEROVA E. V.

    2015-12-01

    Full Text Available Raising of problem. At the problem solving about determination of deflected mode (DM of build constructions by the finite element method (FEM on accuracy of solving substantial influence is rendered by the sizes of effective area of foundation. It is suggested to develop the criteria of determining the size of effective area. Presently at the calculation of vertical fallouts of earth dams with the trapeziform section (fig. 1, is assumed that the epure of contact pressures has a rectangular form [2, 6]. Thus actual epure of contact pressures on the sole of dam has form of trapezoid (fig. 1. Thus, there is a disparity between actual and accepted in the normative documents in the contact pressures on the sole of earth dams. Purpose. At writing of this article we were pursue a purpose to calculate the value of damping coefficient of vertical dead stress on the depth of foundation, trapeziform loading determined and to foundation attached. About it has been already written not a bit in scientific literature [2; 5; 6; 7; 13]. In our view, for determination of vertical fallouts of foundation of earth dams it is necessary to use the formula of D-1 DBN [7], corrected in it the damping coefficient of vertical stress on a depth, conditioned of dam weight, that is to calculate a trapezoidal form of environmental stress (fig. 1. Conclusion. The damping coefficients of vertical stress calculated by us on a depth (tablas. 1 allow more exactly to determine their values, than coefficients, presented in normative documents [7]. This is caused by more complete, than it takes a place in normative documents, in the light of configuration of the environmental stress.

  3. Think the way to measure the Earth Radiation Budget and the Total Solar Irradiance with a small satellites constellation

    Science.gov (United States)

    Meftah, M.; Keckhut, P.; Damé, L.; Bekki, S.; Sarkissian, A.; Hauchecorne, A.

    2018-05-01

    Within the past decade, satellites constellations have become possible and practical. One of the interest to use a satellites constellation is to measure the true Earth Radiation Imbalance, which is a crucial quantity for testing climate models and for predicting the future course of global warming. This measurement presents a high interest because the 2001-2010 decade has not shown the accelerating pace of global warming that most models predict, despite the fact that the greenhouse-gas radiative forcing continues to rise. All estimates (ocean heat content and top of atmosphere) show that over the past decade the Earth radiation imbalance ranges between 0.5 to 1W-2. Up to now, the Earth radiation imbalance has not been measured directly. The only way to measure the imbalance with sufficient accuracy is to measure both the incoming solar radiations (total solar irradiance) and the outgoing terrestrial radiations (top of atmosphere outgoing longwave radiations and shortwave radiations) onboard the same satellite, and ideally, with the same instrument. The incoming solar radiations and the outgoing terrestrial radiations are of nearly equal magnitude of the order of 340.5W-2. The objective is to measure these quantities over time by using differential Sun-Earth measurements (to counter calibration errors) with an accuracy better than 0.05Wm-2 at 1σ. It is also necessary to have redundant instruments to track aging in space in order to measure during a decade and to measure the global diurnal cycle with a dozen satellites. Solar irradiance and Earth Radiation Budget (SERB) is a potential first in orbit demonstration satellite. The SERB nano-satellite aims to measure on the same platform the different components of the Earth radiation budget and the total solar irradiance. Instrumental payloads (solar radiometer and Earth radiometers) can acquire the technical maturity for the future large missions (constellation that insure global measurement cover) by flying in a

  4. Stress-induced hyperglycaemia and venous thromboembolism following total hip or total knee arthroplasty Analysis from the RECORD trials

    NARCIS (Netherlands)

    Cohn, Danny M.; Hermanides, Jeroen; DeVries, J. Hans; Kamphuisen, Pieter-Willem; Kuhls, Silvia; Homering, Martin; Hoekstra, Joost B. L.; Lensing, Anthonie W. A.; Büller, Harry R.

    2012-01-01

    Stress-induced hyperglycaemia is common during orthopaedic surgery. In addition, hyperglycaemia activates coagulation. The aim of the study was to assess whether stress-induced hyperglycaemia is associated with symptomatic or asymptomatic venous thromboembolism (VTE) following orthopaedic surgery.

  5. Comparison of stress and total energy methods for calculation of elastic properties of semiconductors.

    Science.gov (United States)

    Caro, M A; Schulz, S; O'Reilly, E P

    2013-01-16

    We explore the calculation of the elastic properties of zinc-blende and wurtzite semiconductors using two different approaches: one based on stress and the other on total energy as a function of strain. The calculations are carried out within the framework of density functional theory in the local density approximation, with the plane wave-based package VASP. We use AlN as a test system, with some results also shown for selected other materials (C, Si, GaAs and GaN). Differences are found in convergence rate between the two methods, especially in low symmetry cases, where there is a much slower convergence for total energy calculations with respect to the number of plane waves and k points used. The stress method is observed to be more robust than the total energy method with respect to the residual error in the elastic constants calculated for different strain branches in the systems studied.

  6. Stress-reaction during hypokinesia and its effect on total resistance of the animal body

    International Nuclear Information System (INIS)

    Chernov, I.P.

    1980-01-01

    In the experiments on rats, shown has been that three-phase stress-reaction develops during the hypokinetic syndrome formation. This reaction is confirmed by specific changes of general state of the organism, body mass and by the activity of hypothalamic-hypophysial-adrenal system evaluated by oscillations of relative mass of pituitary body and adrenal glands and by karyometry of neuron of the hypothalamus arcuate nuclear and cells of zona fasciculata of adrenal glands. The hypokinetic stress affects the total resistance of the body, its sensitivity to gamma-irradiation in the dose of 800 rad. On the definite stage of development the hypokinetic stress forms the state of heightened ''cross'' stability

  7. On to what extent stresses resulting from the earth's surface trigger earthquakes

    Science.gov (United States)

    Klose, C. D.

    2009-12-01

    The debate on static versus dynamic earthquake triggering mainly concentrates on endogenous crustal forces, including fault-fault interactions or seismic wave transients of remote earthquakes. Incomprehensibly, earthquake triggering due to surface processes, however, still receives little scientific attention. This presentation continues a discussion on the hypothesis of how “tiny” stresses stemming from the earth's surface can trigger major earthquakes, such as for example, China's M7.9 Wenchuan earthquake of May 2008. This seismic event is thought to be triggered by up to 1.1 billion metric tons of water (~130m) that accumulated in the Minjiang River Valley at the eastern margin of the Longmen Shan. Specifically, the water level rose by ~80m (static), with additional seasonal water level changes of ~50m (dynamic). Two and a half years prior to mainshock, static and dynamic Coulomb failure stresses were induced on the nearby Beichuan thrust fault system at <17km depth. Triggering stresses were equivalent to levels of daily tides and perturbed a fault area measuring 416+/-96km^2. The mainshock ruptured after 2.5 years when only the static stressing regime was predominant and the transient stressing (seasonal water level) was infinitesimal small. The short triggering delay of about 2 years suggests that the Beichuan fault might have been near the end of its seismic cycle, which may also confirm what previous geological findings have indicated. This presentation shows on to what extend the static and 1-year periodic triggering stress perturbations a) accounted for equivalent tectonic loading, given a 4-10kyr earthquake cycle and b) altered the background seismicity beneath the valley, i.e., daily event rate and earthquake size distribution.

  8. Cement stress predictions after anatomic total shoulder arthroplasty are correlated with preoperative glenoid bone quality.

    Science.gov (United States)

    Terrier, Alexandre; Obrist, Raphaël; Becce, Fabio; Farron, Alain

    2017-09-01

    We hypothesized that biomechanical parameters typically associated with glenoid implant failure after anatomic total shoulder arthroplasty (aTSA) would be correlated with preoperative glenoid bone quality. We developed an objective automated method to quantify preoperative glenoid bone quality in different volumes of interest (VOIs): cortical bone, subchondral cortical plate, subchondral bone after reaming, subchondral trabecular bone, and successive layers of trabecular bone. Average computed tomography (CT) numbers (in Hounsfield units [HU]) were measured in each VOI from preoperative CT scans. In parallel, we built patient-specific finite element models of simulated aTSAs to predict cement stress, bone-cement interfacial stress, and bone strain around the glenoid implant. CT measurements and finite element predictions were obtained for 20 patients undergoing aTSA for primary glenohumeral osteoarthritis. We tested all linear correlations between preoperative patient characteristics (age, sex, height, weight, glenoid bone quality) and biomechanical predictions (cement stress, bone-cement interfacial stress, bone strain). Average CT numbers gradually decreased from cortical (717 HU) to subchondral and trabecular (362 HU) bone. Peak cement stress (4-10 MPa) was located within the keel hole, above the keel, or behind the glenoid implant backside. Cement stress, bone-cement interfacial stress, and bone strain were strongly negatively correlated with preoperative glenoid bone quality, particularly in VOIs behind the implant backside (subchondral trabecular bone) but also in deeper trabecular VOIs. Our numerical study suggests that preoperative glenoid bone quality is an important parameter to consider in aTSA, which may be associated with aseptic loosening of the glenoid implant. These initial results should now be confronted with clinical and radiologic outcomes. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc

  9. Decreased total antioxidant capacity and increased oxidative stress in passive smoker infants and their mothers.

    Science.gov (United States)

    Aycicek, Ali; Erel, Ozcan; Kocyigit, Abdurrahim

    2005-12-01

    Smoking has many adverse health effects in infants and adults. The purpose of the study was to study the effect of passive cigarette smoking on oxidative and antioxidative status of plasma in passive smoker infants and their mothers and to compare with those of non-smokers. Subjects were randomly chosen from infants aged 8-26 weeks and their mothers aged 20-34 years. Passive smoker infants (n = 29) and their mothers (n = 29) were defined as having other family members who smoked six or more cigarettes per day continually for at least 8 weeks. Non-smokers were defined as infants (n = 30) and their mothers (n = 24) who had never been exposed to passive smoking. The antioxidative status of plasma were perused by measuring the total antioxidant capacity. Oxidative status was evaluated by predicating total peroxide level, oxidative stress index, protein oxidation and lipid peroxidation. Plasma concentrations of total antioxidant capacity were significantly lower in passive smoker infants and their mothers than non-passive smoker infants and their mothers. However, lipid peroxidation and oxidative stress index were remarkably higher in passive smoker infants and their mothers than those of non-passive smoker infants and their mothers. There were significant correlations between the oxidative and antioxidative parameters of the passive smoker infants and their mothers. Oxidants are increased and antioxidants are decreased in passive smoker infants and their mothers than those of non-smokers. Passive smoker infants and their mothers are exposed to potent oxidative stress.

  10. Stress-Activated Electric Currents in the Earth Crust: How they Can and Cannot Flow (Invited)

    Science.gov (United States)

    Freund, F. T.; Bleier, T. E.; Bortnik, J.; Dahlgren, R.

    2010-12-01

    Dormant electronic charge carriers exist in rocks. They “wake up” when stresses are applied: electrons e’ and positive holes, h., the latter being defect electrons in the oxygen anion sublattice of minerals [1, 2]. The h. can flow out of the stressed subvolume. They can spread into the unstressed surrounding, turning the rocks into p-type semiconductors. They travel fast and far using energy levels at the upper edge of the valence bands. Contrary to the h., the co-activated electrons e’ cannot flow out and propagate through unstressed rocks: they are stuck in the activation volume. The situation is akin to that in an electrochemical battery except that, in the “rock battery”, the positive charge carriers are not cations but positive holes h.. In the laboratory it is easy to close the battery circuit by offering the electrons a metal contact and connecting the stressed and unstressed rock with a metal wire. This is useful to demonstrate the functioning of the “rock battery”. In the field the h. outflow from a stressed rock volume is restricted as long as there is no return path. This is an important point when we try to understand why pre-earthquake EM emission is widely considered “unreliable” [3, 4]. However, there are at least three conditions, under which circuit closure can be achieved in the field under realistic pre-earthquake situations: (i) via n-type conducting rocks; (ii) via electrolytic conductivity of water; and (iii) via the air when the air above the epicentral region becomes highly ionized. We report on examples where these three conditions might have allowed large currents to flow and strong EM signals to be emitted. [1] Freund, F.T. et al.: Electric currents streaming out of stressed igneous rocks - A step towards understanding pre-earthquake low frequency EM emissions, Phys. Chem. Earth 31, 389-396 (2006). [2] Freund, F.T.: Charge generation and propagation in rocks, J. Geodyn. 33, 545-572 (2002). [3] Johnston, M.J.S. and

  11. The effect of acid rain stress on membrane protective system of spinach and the conservation of rare earth elements

    International Nuclear Information System (INIS)

    Chongling, Y; Yetang, H.

    1998-01-01

    Full text: Based on pot experiments, the effect of acid rain stress on membrane protective system of spinach and the effect of rare earth elements has been studied. The results showed, stress of acid rain resulted in decrease of over all level of superoxide dismutase activity, catalase activity and increase of peroxidase (POD) activity. After being treated by rare earth elements, the overall level of superoxide dismutase activity and catalase activity were increased and the peak value of activity variation curve moved toward to the direction of higher acidity. POD activity increased slightly, comparing with the plants that hadn't been treated by rare earth elements under same acid rain condition; the three important enzymes of membrane protective system could be kept on a relatively stable level. It was clear that in relative lower acidity condition, rare earth elements can reduce the impact of acid rain on the membrane protective system

  12. Plasma oxidative stress and total thiol levels in Crimean-Congo hemorrhagic fever.

    Science.gov (United States)

    Karadag-Oncel, Eda; Erel, Ozcan; Ozsurekci, Yasemin; Caglayik, Dilek Yagci; Kaya, Ali; Gozel, Mustafa Gokhan; Icagasioglu, Fusun Dilara; Engin, Aynur; Korukluoglu, Gulay; Uyar, Yavuz; Elaldi, Nazif; Ceyhan, Mehmet

    2014-01-01

    In this study, we investigated the pro- and antioxidant status of patients with a pathogenesis of Crimean-Congo hemorrhagic fever (CCHF) in terms of their role in its pathogenesis. During the study period, 34 children and 41 adults were diagnosed with CCHF. The control group consisted of healthy age- and gender-matched children and adults. Serum levels of the total antioxidant capacity (TAC), total oxidant status (TOS), oxidative stress index (OSI), and plasma total thiol (TTL) were evaluated and compared between groups. The difference in mean TAC values between CCHF patients and healthy controls was not statistically significant (P > 0.05). Mean TOS, OSI, and TTL values were significantly lower in CCHF patients than in healthy controls (P 0.05). Our results suggest that TTL may play a more important role in CCHF pathogenesis than the other parameters investigated. The mean TOS and OSI values were higher in the control group than in CCHF patients.

  13. Oxidative stress and total antioxidant status in term newborns and their mothers

    Directory of Open Access Journals (Sweden)

    Maria Wilinska

    2015-12-01

    Full Text Available The peripartum period and delivery are considered critical for maintaining a balance between the production of free oxygen radicals and functional incompetence of the antioxidant system of a foetus and a neonate. [b]Objective.[/b] The aim of the study was to evaluate the oxidoreductive state of mothers and their newborns immediately after delivery and in the first few days after birth. [b]Method.[/b] Eighty-five mothers and their healthy, term newborns were included into the prospective study. Total antioxidant capacity (TAC and thiobarbituric acid reactive substances (TBARS in maternal placenta and milk, as well as blood and urine of the neonates on the first and third day after birth, were examined. [b]Results.[/b] Elevated levels of TBARS were found in maternal placenta and neonatal blood on the third day after birth, but low concentrations were observed in maternal milk. On the contrary, total antioxidant status (TAS showed a declining tendency in neonatal blood and an increasing tendency in breast milk. Markers of oxidative stress and antioxidant capacity were independent of the mode of delivery. [b]Conclusions.[/b] Values of oxidative stress markers in mothers and newborns immediately after birth were elevated and increased further during the first few days of neonatal life. Breast milk was the only nutritional substance with high antioxidant activity. At the same time, TBARS levels in breast milk decreased, which might indicate its protective role in reducing oxidative stress in newborns.

  14. Rhynchophylla total alkaloid rescues autophagy, decreases oxidative stress and improves endothelial vasodilation in spontaneous hypertensive rats.

    Science.gov (United States)

    Li, Chao; Jiang, Feng; Li, Yun-Lun; Jiang, Yue-Hua; Yang, Wen-Qing; Sheng, Jie; Xu, Wen-Juan; Zhu, Qing-Jun

    2018-03-01

    Autophagy plays an important role in alleviating oxidative stress and stabilizing atherosclerotic plaques. However, the potential role of autophagy in endothelial vasodilation function has rarely been studied. This study aimed to investigate whether rhynchophylla total alkaloid (RTA) has a positive role in enhancing autophagy through decreasing oxidative stress, and improving endothelial vasodilation. In oxidized low-density lipoprotein (ox-LDL)-treated human umbilical vein endothelial cells (HUVECs), RTA (200 mg/L) significantly suppressed ox-LDL-induced oxidative stress through rescuing autophagy, and decreased cell apoptosis. In spontaneous hypertensive rats (SHR), administration of RTA (50 mg·kg -1 ·d -1 , ip, for 6 weeks) improved endothelin-dependent vasodilation of thoracic aorta rings. Furthermore, RTA administration significantly increased the antioxidant capacity and alleviated oxidative stress through enhancing autophagy in SHR. In ox-LDL-treated HUVECs, we found that the promotion of autophagy by RTA resulted in activation of the AMP-activated protein kinase (AMPK) signaling pathway. Our results show that RTA treatment rescues the ox-LDL-induced autophagy impairment in HUVECs and improves endothelium-dependent vasodilation function in SHR.

  15. Stress variations during a glacial cycle at 500 m depth in Forsmark and Oskarshamn: Earth model effects

    Energy Technology Data Exchange (ETDEWEB)

    Lund, Bjoern [Uppsala Univ. (Sweden). Dept. of Earth Sciences

    2006-06-15

    This study has considered the response to a glaciation of Earth models of increasingly complex structure in elastic parameters and viscosity. The models are one-dimensional in the sense that they vary only in the depth direction, i.e. there are only uniform, horizontal layers in the models. I find that as the complexity of the models increase, and the properties of the uppermost kilometer of the Earth become less affected by average properties from deeper down, the flexural stresses at 500 m depth decrease, as expected. A lower Young's modulus, lower compressibility and lower density in the uppermost layer all act to lower the stresses. However, the three properties act differently on the resulting response. Introducing layering in Young's modulus generally decreases the stresses all along a profile through the ice model. Going from incompressible to compressible models affect the stresses outside the ice edge significantly more than the stresses under the ice sheet. Introducing layering in density conversely affect the stresses under the ice sheet more than those outside the ice edge. The combined effects of the most complex models tested here show that the glacially induced horizontal stresses at 500 m depth decrease to levels very similar in magnitude to the loading stress. There are, however, temporal variations in these horizontal stresses that do not follow the loading stress and which induce tensional or compressional horizontal stresses that persist when no ice is present.As is well known, changes in viscosity structure has a very large effect on the Earth response. Viscosity affect both the magnitudes of the induced stresses and the temporal behavior of the stress evolution. This is confirmed in the current study.The glacially induced stresses for some of the models have been used in combination with the current background stress field at Forsmark and Oskarshamn, as estimated in SKB's site models, to evaluate fault stability throughout a

  16. Stress variations during a glacial cycle at 500 m depth in Forsmark and Oskarshamn: Earth model effects

    International Nuclear Information System (INIS)

    Lund, Bjoern

    2006-06-01

    This study has considered the response to a glaciation of Earth models of increasingly complex structure in elastic parameters and viscosity. The models are one-dimensional in the sense that they vary only in the depth direction, i.e. there are only uniform, horizontal layers in the models. I find that as the complexity of the models increase, and the properties of the uppermost kilometer of the Earth become less affected by average properties from deeper down, the flexural stresses at 500 m depth decrease, as expected. A lower Young's modulus, lower compressibility and lower density in the uppermost layer all act to lower the stresses. However, the three properties act differently on the resulting response. Introducing layering in Young's modulus generally decreases the stresses all along a profile through the ice model. Going from incompressible to compressible models affect the stresses outside the ice edge significantly more than the stresses under the ice sheet. Introducing layering in density conversely affect the stresses under the ice sheet more than those outside the ice edge. The combined effects of the most complex models tested here show that the glacially induced horizontal stresses at 500 m depth decrease to levels very similar in magnitude to the loading stress. There are, however, temporal variations in these horizontal stresses that do not follow the loading stress and which induce tensional or compressional horizontal stresses that persist when no ice is present.As is well known, changes in viscosity structure has a very large effect on the Earth response. Viscosity affect both the magnitudes of the induced stresses and the temporal behavior of the stress evolution. This is confirmed in the current study.The glacially induced stresses for some of the models have been used in combination with the current background stress field at Forsmark and Oskarshamn, as estimated in SKB's site models, to evaluate fault stability throughout a glacial cycle. The

  17. Sensitivity of total stress to changes in externally applied water pressure in KBS-3 buffer bentonite

    International Nuclear Information System (INIS)

    Harrington, J.F.; Birchall, D.J.

    2007-04-01

    In the current Swedish repository design concept, composite copper and steel canisters containing spent nuclear fuel will be placed in large diameter disposal boreholes drilled into the floor of the repository tunnels. The space around each canister will be filled with pre-compacted bentonite which over time will draw in the surrounding ground water and swell, closing up any construction joints. However, for the purposes of performance assessment, it is necessary to consider the effect of glacial loading of a future repository and its impact on the mechanical behaviour of the bentonite, in particular, the sensitivity of total stress to changes in porewater pressure (backpressure). Two experimental histories have been undertaken using a custom-designed constant volume and radial flow (CVRF) apparatus. In both tests backpressure was varied in a number of incremental and decremental cycles while total stress, porewater pressure and volumetric flow rate were continuously monitored. The swelling pressure of the buffer clay at dry densities of 1.8 Mg/m 3 and 1.61 Mg/m 3 was determined to be around 5.5 MPa and 7.2 MPa respectively. For initial ascending porewater pressure histories the average proportionality factor α ranged from 0.86 and 0.92. Data exhibited a general trend of increasing α with increasing backpressure. In test Mx80-11 this was supported by analysis of the water inflow data which indicated a reduction in system compressibility. Asymptotic values of porewater pressure within the clay are in good agreement with externally applied backpressure values. Inspection of data provides no evidence for the development of hydraulic thresholds within the clay, subject to the boundary conditions of this test geometry. Analysis of the stress data demonstrates significant hysteresis between ascending and descending porewater pressure histories. The amount of hysteresis appears to be linked to the magnitude of the backpressure applied to the specimen, suggesting some

  18. Sensitivity of total stress to changes in externally applied water pressure in KBS-3 buffer bentonite

    Energy Technology Data Exchange (ETDEWEB)

    Harrington, J.F.; Birchall, D.J. [British Geological Survey, Chemical and Biological Hazards Programme, Kingsley Dunham Centre (United Kingdom)

    2007-04-15

    In the current Swedish repository design concept, composite copper and steel canisters containing spent nuclear fuel will be placed in large diameter disposal boreholes drilled into the floor of the repository tunnels. The space around each canister will be filled with pre-compacted bentonite which over time will draw in the surrounding ground water and swell, closing up any construction joints. However, for the purposes of performance assessment, it is necessary to consider the effect of glacial loading of a future repository and its impact on the mechanical behaviour of the bentonite, in particular, the sensitivity of total stress to changes in porewater pressure (backpressure). Two experimental histories have been undertaken using a custom-designed constant volume and radial flow (CVRF) apparatus. In both tests backpressure was varied in a number of incremental and decremental cycles while total stress, porewater pressure and volumetric flow rate were continuously monitored. The swelling pressure of the buffer clay at dry densities of 1.8 Mg/m{sup 3} and 1.61 Mg/m{sup 3} was determined to be around 5.5 MPa and 7.2 MPa respectively. For initial ascending porewater pressure histories the average proportionality factor {alpha} ranged from 0.86 and 0.92. Data exhibited a general trend of increasing {alpha} with increasing backpressure. In test Mx80-11 this was supported by analysis of the water inflow data which indicated a reduction in system compressibility. Asymptotic values of porewater pressure within the clay are in good agreement with externally applied backpressure values. Inspection of data provides no evidence for the development of hydraulic thresholds within the clay, subject to the boundary conditions of this test geometry. Analysis of the stress data demonstrates significant hysteresis between ascending and descending porewater pressure histories. The amount of hysteresis appears to be linked to the magnitude of the backpressure applied to the specimen

  19. Bilateral periprosthetic tibial stress fracture after total knee arthroplasty: A case report.

    Science.gov (United States)

    Ozdemir, Guzelali; Azboy, Ibrahim; Yilmaz, Baris

    2016-01-01

    Periprosthetic fractures around the knee after total knee arthroplasty can be seen in the femur, tibia and patella. The tibial fractures are rare cases. Our case with bilateral tibial stress fracture developed after total knee arthroplasty (TKA) is the first of its kind in the literature. 75-year-old male patient with bilateral knee osteoarthritis had not benefited from conservative treatment methods previously applied. Left TKA was applied. In the second month postoperatively, periprosthetic tibial fracture was identified and osteosynthesis was implemented with locked tibia proximal plate-screw. Bone union in 12 weeks was observed in his follow-ups. After 15 months of his first operation, TKA was applied to the right knee. Postoperatively in the second month, as in the first operation, periprosthetic tibial fracture was detected. Osteosynthesis with locking plate-screw was applied and union in 12 weeks was observed in his follow-up. He was seen mobilized independently and without support in the last control of the case made in the 24th month after the second operation. The number of TKA applications is expected to increase in the future. The incidence of periprosthetic fractures should also be expected to increase in these cases. Periprosthetic tibial fractures after TKA are rarely seen. The treatment of periprosthetic fractures around the knee after TKA can be difficult. In the case of persistent pain in the upper end of the tibia after the surgery, stress fracture should be considered. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  20. Oxidative stress and lowered total antioxidant status are associated with a history of suicide attempts.

    Science.gov (United States)

    Vargas, Heber Odebrecht; Nunes, Sandra Odebrecht Vargas; Pizzo de Castro, Marcia; Bortolasci, Chiara Cristina; Sabbatini Barbosa, Décio; Kaminami Morimoto, Helena; Venugopal, Kamalesh; Dodd, Seetal; Maes, Michael; Berk, Michael

    2013-09-25

    There is evidence that depression is accompanied by inflammation, oxidative and nitrosative stress (O&NS) and metabolic disorders. However links between oxidative stress and suicide attempts in depressed patients are poorly understood. This study examines whether a history of suicide attempts is associated with inflammation, O&NS and metabolic disorders. Blood specimens were collected from study participants aged 18-60 (N=342) recruited at the State University of Londrina, Brazil, and measured for oxidative stress biomarkers: nitric oxide metabolites (NOx), lipid hydroperoxides, malondialdehyde, advanced oxidation protein products and plasma total antioxidant potential (TRAP); inflammatory biomarkers: fibrinogen, high-sensitivity C-reactive protein, erythrocyte sedimentation rate, interleukin-6 and tumor necrosis factor-α; and metabolic variables. Subjects were divided into those with (n=141) and without (n=201) a history of suicidal attempts. Individuals with a history of suicide attempts had significantly higher levels of NOx and lipid hydroperoxides and lowered TRAP as compared to individuals without suicide attempts. There were no significant associations between a history of suicide attempts and inflammatory and metabolic biomarkers and metabolic syndrome. Logistic regression showed that both unipolar and bipolar disorder, female gender, smoking behavior and lipid hydroperoxides were significantly associated with a history of suicide attempts. The combined effects of oxidative stress, smoking, depression, female gender were independent from classical risk factors, including marital status, years of education and anxiety. O&NS as well as lowered antioxidant levels may play a role in the pathophysiology of suicidal behavior independently from the effects of depression and smoking, both of which are associated with increased O&NS, and classical suicide predictors, such as years of education and marital status. © 2013 Published by Elsevier B.V.

  1. Total workload, work stress and perceived symptoms in Swedish male and female white-collar employees.

    Science.gov (United States)

    Krantz, Gunilla; Berntsson, Leeni; Lundberg, Ulf

    2005-04-01

    The aim of this study was to analyse how paid work, unpaid household tasks, child care, work-child care interactions and perceived work stress are associated with reported symptoms in male and female white-collar employees. A questionnaire was mailed to 1300 men and 1300 women belonging to the white-collar sector, with at least 35 hours of regular employment a week and a participant age of between 32 and 58 years. It contained items relating to total workload (hours spent on paid work, unpaid household tasks and childcare), subjective indices for work stress and symptoms. The response rate was 65% (743 women; 595 men). Gender difference in symptom prevalence was tested by analyses of variance. Odds ratios were used to estimate the bivariate associations between work-related variables and symptom prevalence. A multivariate analysis estimated the effect of paid and unpaid work interaction, work-childcare interplay and possible synergy. The frequency and severity of symptoms was higher in women than in men (P women's health was determined by the interaction between conditions at work and household duties (OR 2.09; 1.06-4.14), whereas men responded more selectively to long working hours, i.e. >50 h/week (OR 1.61; 1.02-2.54). However, childcare (women.

  2. Numerical model of total artificial heart hemodynamics and the effect of its size on stress accumulation.

    Science.gov (United States)

    Marom, Gil; Chiu, Wei-Che; Slepian, Marvin J; Bluestein, Danny

    2014-01-01

    The total artificial heart (TAH) is a bi-ventricular mechanical circulatory support device that replaces the heart in patients with end-stage congestive heart failure. The device acts as blood pump via pneumatic activation of diaphragms altering the volume of the ventricular chambers. Flow in and out of the ventricles is controlled by mechanical heart valves. The aim of this study is to evaluate the flow regime in the TAH and to estimate the thrombogenic potential during systole. Toward that goal, three numerical models of TAHs of differing sizes, that include the deforming diaphragm and the blood flow from the left chamber to the aorta, are introduced. A multiphase model with injection of platelet particles is employed to calculate their trajectories. The shear stress accumulation in the three models are calculated along the platelets trajectories and their probability density functions, which represent the `thrombogenic footprint' of the device are compared. The calculated flow regime successfully captures the mitral regurgitation and the flows that open and close the aortic valve during systole. Physiological velocity magnitudes are found in all three models, with higher velocities and increased stress accumulation predicted for smaller devices.

  3. TOMS/Earth Probe Total Column Ozone Daily L3 Global 1x1.25 deg Lat/Lon Grid V008

    Data.gov (United States)

    National Aeronautics and Space Administration — This data product contains TOMS/Earth Probe Total Column Ozone Daily L3 Global 1x1.25 deg Lat/Lon Grid Version 8 data in ASCII format. (The shortname for this...

  4. Combined nitrogen limitation and cadmium stress stimulate total carbohydrates, lipids, protein and amino acid accumulation in Chlorella vulgaris (Trebouxiophyceae)

    Energy Technology Data Exchange (ETDEWEB)

    Chia, Mathias Ahii, E-mail: chia28us@yahoo.com [Department of Botany, Federal University of São Carlos, Rodovia Washington Luis km 235, São Carlos, SP Cep 13565905 (Brazil); Lombardi, Ana Teresa [Department of Botany, Federal University of São Carlos, Rodovia Washington Luis km 235, São Carlos, SP Cep 13565905 (Brazil); Graça Gama Melão, Maria da [Department of Hydrobiology, Federal University of São Carlos, Rodovia Washington Luis km 235, São Carlos, SP Cep 13565905 (Brazil); Parrish, Christopher C. [Department of Ocean Sciences, Memorial University of Newfoundland, St. John’s, Newfoundland A1C 5S7 (Canada)

    2015-03-15

    Highlights: • Chlorella vulgaris was exposed to Cd under varying N concentrations. • Growth rate and cell density decreased with increasing Cd stress and N limitation. • Dry weight, chlorophyll a, total lipid, carbohydrate and protein were accumulated. • Amino acids like proline and glutamine were accumulated under N and Cd stress. • Changes in amino acid composition are sensitive biomarkers for Cd and N stress. - Abstract: Metals have interactive effects on the uptake and metabolism of nutrients in microalgae. However, the effect of trace metal toxicity on amino acid composition of Chlorella vulgaris as a function of varying nitrogen concentrations is not known. In this research, C. vulgaris was used to investigate the influence of cadmium (10{sup −7} and 2.0 × 10{sup −8} mol L{sup −1} Cd) under varying nitrogen (2.9 × 10{sup −6}, 1.1 × 10{sup −5} and 1.1 × 10{sup −3} mol L{sup −1} N) concentrations on its growth rate, biomass and biochemical composition. Total carbohydrates, total proteins, total lipids, as well as individual amino acid proportions were determined. The combination of Cd stress and N limitation significantly inhibited growth rate and cell density of C. vulgaris. However, increasing N limitation and Cd stress stimulated higher dry weight and chlorophyll a production per cell. Furthermore, biomolecules like total proteins, carbohydrates and lipids increased with increasing N limitation and Cd stress. Ketogenic and glucogenic amino acids were accumulated under the stress conditions investigated in the present study. Amino acids involved in metal chelation like proline, histidine and glutamine were significantly increased after exposure to combined Cd stress and N limitation. We conclude that N limitation and Cd stress affects the physiology of C. vulgaris by not only decreasing its growth but also stimulating biomolecule production.

  5. 77 FR 62396 - Annual Company-Run Stress Test Requirements for Banking Organizations With Total Consolidated...

    Science.gov (United States)

    2012-10-12

    ... minimum risk-based capital requirements.\\3\\ Stress testing is one tool that helps both bank supervisors... the FDIC and the OCC to help to ensure that the company-run stress testing regulations are consistent... purposes of the annual company-run stress tests so that the same set of scenarios can be used to conduct...

  6. Combined nitrogen limitation and cadmium stress stimulate total carbohydrates, lipids, protein and amino acid accumulation in Chlorella vulgaris (Trebouxiophyceae).

    Science.gov (United States)

    Chia, Mathias Ahii; Lombardi, Ana Teresa; da Graça Gama Melão, Maria; Parrish, Christopher C

    2015-03-01

    Metals have interactive effects on the uptake and metabolism of nutrients in microalgae. However, the effect of trace metal toxicity on amino acid composition of Chlorella vulgaris as a function of varying nitrogen concentrations is not known. In this research, C. vulgaris was used to investigate the influence of cadmium (10(-7) and 2.0×10(-8)molL(-1) Cd) under varying nitrogen (2.9×10(-6), 1.1×10(-5) and 1.1×10(-3)molL(-1)N) concentrations on its growth rate, biomass and biochemical composition. Total carbohydrates, total proteins, total lipids, as well as individual amino acid proportions were determined. The combination of Cd stress and N limitation significantly inhibited growth rate and cell density of C. vulgaris. However, increasing N limitation and Cd stress stimulated higher dry weight and chlorophyll a production per cell. Furthermore, biomolecules like total proteins, carbohydrates and lipids increased with increasing N limitation and Cd stress. Ketogenic and glucogenic amino acids were accumulated under the stress conditions investigated in the present study. Amino acids involved in metal chelation like proline, histidine and glutamine were significantly increased after exposure to combined Cd stress and N limitation. We conclude that N limitation and Cd stress affects the physiology of C. vulgaris by not only decreasing its growth but also stimulating biomolecule production. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Effect of cup inclination on predicted contact stress-induced volumetric wear in total hip replacement.

    Science.gov (United States)

    Rijavec, B; Košak, R; Daniel, M; Kralj-Iglič, V; Dolinar, D

    2015-01-01

    In order to increase the lifetime of the total hip endoprosthesis, it is necessary to understand mechanisms leading to its failure. In this work, we address volumetric wear of the artificial cup, in particular the effect of its inclination with respect to the vertical. Volumetric wear was calculated by using mathematical models for resultant hip force, contact stress and penetration of the prosthesis head into the cup. Relevance of the dependence of volumetric wear on inclination of the cup (its abduction angle ϑA) was assessed by the results of 95 hips with implanted endoprosthesis. Geometrical parameters obtained from standard antero-posterior radiographs were taken as input data. Volumetric wear decreases with increasing cup abduction angle ϑA. The correlation within the population of 95 hips was statistically significant (P = 0.006). Large cup abduction angle minimises predicted volumetric wear but may increase the risk for dislocation of the artificial head from the cup in the one-legged stance. Cup abduction angle and direction of the resultant hip force may compensate each other to achieve optimal position of the cup with respect to wear and dislocation in the one-legged stance for a particular patient.

  8. Instrumental and laboratory assessment of stressful remodelling processes in bone tissue at total hip replacement

    Directory of Open Access Journals (Sweden)

    E.V. Karjakina

    2010-06-01

    Full Text Available Research objective is to estimate stressful remodelling features of bone tissue according to the densitometry data and to the level of biochemical markers of bone resorption and formation in total hip replacement (THR. Bone tissue mineral density (BTMD, condition of calcium-phosphoric metabolism and biochemical markers of bone formation (osteocalcin and bone isoenzyme of alkaline phosphatase and resorption (С-terminal bodypeptide of the I type collagen have been determined in 52 patients with coxarthrosis of ll-lll stages with marked joint dysfunction before and after THR. The control group included 24 donors. The data were considered to be reliable when the probability index was р<0,05. The reliable (р<0,05 change of BTMD was determined only in 3-6 months after the operation, whereas the change of biochemical markers of remodeling had already been done after 1,5-3 months, allowing to define the group of patients with obvious negative bone balance: strong predominance of resorption processes without compensation of the subsequent adequate osteogenesis, that subsequently could lead to significant bone tissue deficiency in the area adjacent to the endoprosthesis. Changes of indices of calcium-phosphoric metabolism were not certain during the investigation term. ln conclusion it is to state that biochemical markers of remodeling in comparison with BTMD allow to estimate objectively features of adaptive bone tissue remodeling after THR in earlier periods and to define group of patients with sharp intensification of metabolism and obvious negative bone balance

  9. Measures of total stress-induced blood pressure responses are associated with vascular damage.

    Science.gov (United States)

    Nazzaro, Pietro; Seccia, Teresa; Vulpis, Vito; Schirosi, Gabriella; Serio, Gabriella; Battista, Loredana; Pirrelli, Anna

    2005-09-01

    The role of cardiovascular reactivity to study hypertension, and the assessment methods, are still controversial. We aimed to verify the association of hypertension and vascular damage with several measures of cardiovascular response. We studied 40 patients with normal-high (132 +/- 1/87 +/- 1 mm Hg) blood pressure (Group 1) and 80 untreated hypertensive subjects. Postischemic forearm vascular resistance (mFVR) served to differentiate hypertensive subjects (142 +/- 2/92 +/- 1 mm Hg v 143 +/- 2/94 +/- 2 mm Hg, P = NS) with a lower (Group 2) and higher (Group 3) hemodynamic index of vascular damage (4.8 +/- .05 v 6.3 +/- .09, P blood pressure, heart rate, forearm blood flow, and vascular resistance. Reactivity measures included: a) change from baseline, b) residualized score, c) cumulative change from baseline and residualized score, and d) total reactivity as area-under-the-curve (AUC), including changes occurring during baseline and recovery phases. The AUC of systolic blood pressure, diastolic blood pressure, and mFVR progressively increased in the groups (P AUC of SBP, DBP, and forearm blood flow and resistance demonstrated the highest (P AUC of SBP (beta = 0.634) and forearm blood flow (beta = -0.337) were predictive (P blood pressure stress response, as AUC, including baseline and recovery phases, was significantly better associated with hypertension and vascular damage than the other reactivity measures studied.

  10. Total antioxidant capacity, total oxidant status and oxidative stress index in the men exposed to 1.5 T static magnetic field.

    Science.gov (United States)

    Sirmatel, O; Sert, C; Sirmatel, F; Selek, S; Yokus, B

    2007-06-01

    The aim of this study was to investigate the effects of a high-strength magnetic field produced by a magnetic resonance imaging (MRI) apparatus on oxidative stress. The effects of a 1.5 T static magnetic field on the total antioxidant capacity (TAC), total oxidant status (TOS) and oxidative stress index (OSI) in male subjects were investigated. In this study, 33 male volunteers were exposed to a 1.5 T static magnetic field for a short time and the TAC, TOS and OSI of each subject were determined. Magnetic field exposure was provided using a magnetic resonance apparatus; radiofrequency was not applied. Blood samples were taken from subjects and TAC, TOS and OSI values were measured using the methods of Erel. TAC showed a significant increase in post-exposures compared to pre-exposures to the magnetic field (p < 0.05). OSI and TOS showed a significant decrease in post-exposures compared to pre-exposures to a 1.5 T magnetic field (for each of two, p < 0.01). The 1.5 T static magnetic field used in the MRI apparatus did not yield a negative effect; on the contrary, it produced the positive effect of decreasing oxidative stress in men following short-term exposure.

  11. Sleep deprived and sweating it out: the effects of total sleep deprivation on skin conductance reactivity to psychosocial stress.

    Science.gov (United States)

    Liu, Jean C J; Verhulst, Silvan; Massar, Stijn A A; Chee, Michael W L

    2015-01-01

    We examined how sleep deprivation alters physiological responses to psychosocial stress by evaluating changes in skin conductance. Between-subjects design with one group allocated to 24 h of total sleep deprivation and the other to rested wakefulness. The study took place in a research laboratory. Participants were 40 healthy young adults recruited from a university. Sleep deprivation and feedback. Electrodermal activity was monitored while participants completed a difficult perceptual task with false feedback. All participants showed increased skin conductance levels following stress. However, compared to well-rested participants, sleep deprived participants showed higher skin conductance reactivity with increasing stress levels. Our results suggest that sleep deprivation augments allostatic responses to increasing psychosocial stress. Consequentially, we propose sleep loss as a risk factor that can influence the pathogenic effects of stress. © 2014 Associated Professional Sleep Societies, LLC.

  12. Geodynamics and Stress State of the Earth's Crust in the Greater and Lesser Caucasus (Azerbaijan) collision region

    Science.gov (United States)

    Babayev, Gulam; Akhmedova, Elnare; Babayev, Elvin

    2017-04-01

    The current study researches the present-day stress state of the Earth's crust within the territory of Azerbaijan by using the database of the international research project "World Stress Map" (WSM). The present stress state was also assessed by exploring the effects of the contemporary topographic properties of Caucasus in three-dimensional frame. Aiming to explore the relative roles of regional tectonic conditions in the definition of stress state of Greater and Lesser Caucasus, stress distribution model was developed by the earthquake data (1998-2016) and by the standard techniques of stress field calculation. The results show that the stress orientations are influenced also by the combination of topography and crust thickness distribution even at very large depth. Stress data and earthquake focal mechanisms indicate that the stress state of the Earth's crust of the Greater and Lesser Caucasus is characterized by the compression predominantly oriented across the regional strike. The model results suggest that the Lesser Caucasus and Kur depression are rotating coherently, with little or no internal deformation in a counter-clockwise rotation located near the north-eastern corner of the Black Sea. Orientation of stress axes well consistent with earthquake focal mechanisms revealed that within Upper and Lower Crusts, earthquakes are predominantly thrust-faulting with a number of normal-faulting and some strike-slip faulting. The map of the focal mechanisms and stress distribution suggests that the research area is characterized by the thrust of horizontal compression trending north-north-east in the western part of the southern Caucasus. In the western part of Azerbaijan, the compression takes place between the Main Caucasus Fault and the Kur depression, which strikes south along the northern margin of the mountain range. In addition, a clear transition from the left-lateral strike slip to the predominantly right-lateral strike slip is observed in the southern of

  13. Contact stresses, pressure and area in a fixed-bearing total ankle replacement: a finite element analysis.

    Science.gov (United States)

    Martinelli, Nicolo; Baretta, Silvia; Pagano, Jenny; Bianchi, Alberto; Villa, Tomaso; Casaroli, Gloria; Galbusera, Fabio

    2017-11-25

    Mobile-bearing ankle implants with good clinical results continued to increase the popularity of total ankle arthroplasty to address endstage ankle osteoarthritis preserving joint movement. Alternative solutions used fixed-bearing designs, which increase stability and reduce the risk of bearing dislocation, but with a theoretical increase of contact stresses leading to a higher polyethylene wear. The purpose of this study was to investigate the contact stresses, pressure and area in the polyethylene component of a new total ankle replacement with a fixed-bearing design, using 3D finite element analysis. A three-dimensional finite element model of the Zimmer Trabecular Metal Total Ankle was developed and assembled based on computed tomography images. Three different sizes of the polyethylene insert were modeled, and a finite element analysis was conducted to investigate the contact pressure, the von Mises stresses and the contact area of the polyethylene component during the stance phase of the gait cycle. The peak value of pressure was found in the anterior region of the articulating surface, where it reached 19.8 MPa at 40% of the gait cycle. The average contact pressure during the stance phase was 6.9 MPa. The maximum von Mises stress of 14.1 MPa was reached at 40% of the gait cycle in the anterior section. In the central section, the maximum von Mises stress of 10.8 MPa was reached at 37% of the gait cycle, whereas in the posterior section the maximum stress of 5.4 MPa was reached at the end of the stance phase. The new fixed-bearing total ankle replacement showed a safe mechanical behavior and many clinical advantages. However, advanced models to quantitatively estimate the wear are need. To the light of the clinical advantages, we conclude that the presented prosthesis is a good alternative to the other products present in the market.

  14. Structural Response of the Earth's Crust to an Extra-Terrestrial Source of Stress by Identifying its Characteristic Pattern

    Science.gov (United States)

    Dasgupta, B.

    2016-12-01

    The earth's crust is a geodynamic realm, which is constantly evolving. Due to its dynamic nature, the crust is constantly being subjected to remodelling. The earth's crustal response to stress is a result of isostatic compensation. The crust is also a living proof of yesteryears' dynamics. Extra-terrestrial agents of deformation refers to meteorites, asteroids etc. These are catastrophic events that influence a larger area (considering larger impact bodies). They effect the crust from outside, hence leave behind very specific structural signatures.Consider an extra-terrestrial object impacting the earth's crust. The problem can be broken down into 3 parts: Pre Impact (kinematics of the object and nature of surface of impact); Syn Impact (dissipation of energy and formation of crater); and Post Impact (structural response, geophysical anomalies and effect on biota)Upon impact, the projectile penetrates the earth's crust to a depth of twice its diameter. Shock waves generated due impact propagate in all possible directions. The reflected waves cause complete melting and vaporization of the impact body. At the same time, increased internal energy of the system melts the target rock. Depending on the thickness and density of crustal matter, its' interaction with the mantle is determined. Data collection from such impact sites is the first step towards its theoretical modeling. Integrating geophysical (seismic, magnetic), paleomagnetic, geochemical and geo-chronological data one can determine the kinematic parameters that governed the event. A working model that illustrates the crustal responses to extraterrestrial stress of extreme magnitude cannot be qualitative. Hence the most fundamental thing at this point is quantification of these parameters. The variables form a `mass-energy equation', a simple theorem in Classical Physics. This project is directed to give the equation its shape. The equation will be the foundation on which the simulation model will rest. Mass

  15. Development of total systems of piping stress analysis and evaluation: ISAPPS

    International Nuclear Information System (INIS)

    Oki, Teizaburo; Koyanagi, Ryoichi; Fukuda, Masanao

    1978-01-01

    IHI has developed the systems of piping stress analysis and evaluation: ISAPPS (IHI Stress Analysis Program for Piping Systems), which are further described in this paper. In addition, the results of structural analysis and heat transfer analysis were confirmed. An example of stress evaluation in accordance with the modified ASME Code Sec. III is shown. ISAPPS consists of the following seven parts, and is designed for easy adoption of other programs by making modifications. 1. Piping design oriented language programs 2. Structural analysis programs 3. Isometric plotting programs 4. Multi-file dumping program 5. Load combination program 6. Heat transfer program 7. Stress evaluation programs As one of the examples of structural analysis programs, IHI make use of the modified SAP IV developed by the University of California. Evaluations of stresses are performed in accordance with: 1. ASME Boiler and Pressure Vessel Code, Sec. III Class 1, 2 and 3 2. ANSI Code, B31.1 and B31.3 3. MITI (Ministry of International Trade and Industry ) Code ISAPPS is very useful for design of nuclear and chemical pipings and so on. (author)

  16. Reflection and transmission of seismic waves under initial stress at the earth's core-mantle boundary

    Directory of Open Access Journals (Sweden)

    Sukhendu Dey

    1980-01-01

    Full Text Available In the present paper the influence of the initial stress is shown on the reflection and transmission of P waves at the core-mantle boundary. Taking a particular value of the inherent initial stress, the variations of reflection and transmission coefficients with respect to the angle of emergence are represented by graphs. These graphs when compared with those having no initial stress show that the effect of the initial stress is to produce a reflected P and S waves with numerically higher amplitudes but a transmitted P wave with smaller amplitude. A method is also indicated in this paper to calculate the actual value of the initial stress near the core-mantle boundary by measuring the amplitudes of incident and reflected P waves.

  17. Comparison of Total Antioxidant Capacity Oxidative Stress and Blood Lipoprotein Parameters in Volleyball Players and Sedentary

    Science.gov (United States)

    Gokhan, Ismail

    2013-01-01

    This study aims to measure, then compare sedentary blood lipoproteins, oxidant- antioxidant state and oxidative stress index in volleyball players. The experimental group of the research consists of regularly practising 20 boys between the ages of 12 and 17, and the control group comprises 32 children practising no particular sports branch, 12 of…

  18. Investigation of Catalase, Proxidase and Total Protein Level in Some Cold Treated Grapevine Cultivars Cold Stress Response

    Directory of Open Access Journals (Sweden)

    M. Karimi Alavijeh

    2016-02-01

    Full Text Available Chilling is an important environmental stress that influences the yield and quality of many agricultural crops. Different plants use different systems to endure this stress and minimize its effects. One of these systems is enzymatic reaction. To find out more about responses of different grapevine species and cultivars to the low temperature conditions, their enzymatic changes were evaluated in a factorial experiment based on randomized complete design with 3 replication during different periods after chilling stress. Leaf samples of plants under cold stress had been taken and maintained in -80 °C until enzyme extraction. Low temperature around 4 °C is sufficient to induce genes that produce chilling acclimatization proteins. In the present study, leaf samples were collected from the plants that were kept at 4 °C during different time intervals, and then total proteins as well as two main antioxidant enzymes (catalase and guaiacolperoxidase activities were measured. Results showed that as temperature decreased, enzymatic activities were increased in six Iranian grapevine cultivars (‘Atabaki’, ‘Khalili-Danedar’, ‘Shahroodi’, ‘Rajabi-Siah’, ‘Askari’ and ‘Bidane-Sefid’ as well as ‘Riparia’, an American species. The highest enzymatic activities of catalase and ceroxidase were recorded in ‘Khalili-Danedar’ and ‘Riparia’. However,the lowest activities were recorded in ‘Rajabi-Siah’, ‘Bidane-Sefid’ and ‘Shahroodi’. For all studied cultivars, peroxidase showed its highest activity at 12 h after chilling stress, then remained constant, while, the highest activity of catalase were recorded at 8 h. In addition, cold stress increased the total protein content for all studied cultivars, in which ‘Khalili-Danedar’ had the highest protein content amongstudied cultivars. Also, the highest proteins content were recorded at 12 h after exposing plants to cold.

  19. Effects of total glucosides of paeony on oxidative stress in the kidney from diabetic rats.

    Science.gov (United States)

    Su, Jing; Zhang, Pei; Zhang, Jing-Jing; Qi, Xiang-Ming; Wu, Yong-Gui; Shen, Ji-Jia

    2010-03-01

    TGP, extracted from the traditional Chinese herb root of Paeonia lactiflora pall, has been shown to have therapeutic effect in experimental diabetic nephropathy. However, its mechanism is not fully understood. In this study, the effects of TGP on oxidative stress were investigated in the kidney of diabetic rats induced by streptozotocin. TGP (50, 100, 200mg/kg) was orally administered once a day for 8 weeks. TGP treatment in all three doses significantly lowered 24 h urinary albumin excretion rate in diabetic rats and attenuated glomerular volume. TGP treatment with 100 and 200mg/kg significantly reduced indices for tubulointerstitial injury in diabetic rats. The level of MDA was significantly increased in the kidney of diabetic rats and attenuated by TGP treatment at the dose of 200mg/kg. TGP treatment in a dose-dependent manner decreased the level of 3-NT protein of the kidney which increased under diabetes. T-AOC was significantly reduced in diabetic rat kidney and remarkably increased by TGP treatment at the dose of 100 and 200mg/kg. Activity of antioxidant enzyme such as SOD, CAT was markedly elevated by TGP treatment with 200mg/kg. Western blot analysis showed that p-p38 MAPK and NF-kappaB p65 protein expression increased in diabetic rat kidney, which were significantly decreased by TGP treatment. It seems likely that oxidative stress is increased in the diabetic rat kidneys, while TGP can prevent diabetes-associated renal damage against oxidative stress.

  20. Total Glucosides of Danggui Buxue Tang Attenuate BLM-Induced Pulmonary Fibrosis via Regulating Oxidative Stress by Inhibiting NOX4

    Science.gov (United States)

    Zhao, Ping; Zhou, Wen-Cheng; Li, De-Lin; Mo, Xiao-Ting; Xu, Liang; Li, Liu-Cheng; Cui, Wen-Hui; Gao, Jian

    2015-01-01

    Pulmonary fibrosis (PF) is a serious chronic lung disease with unknown pathogenesis. Researches have confirmed that oxidative stress which is regulated by NADPH oxidase-4 (NOX4), a main source of reactive oxygen species (ROS), is an important molecular mechanism underlying PF. Previous studies showed that total glucosides of Danggui Buxue Tang (DBTG), an extract from a classical traditional Chinese herbal formula, Danggui Buxue Tang (DBT), attenuated bleomycin-induced PF in rats. However, the mechanisms of DBTG are still not clear. We hypothesize that DBTG attenuates PF through regulating the level of oxidative stress by inhibiting NOX4. And we found that fibrosis indexes hydroxyproline (HYP) and type I collagen (Col-I) were lower in DBTG groups compared with the model group. In addition, the expression of transforming growth factor-β1 (TGF-β1) and expression of alpha smooth muscle actin (α-SMA) were also much more decreased than the model group. For oxidative stress indicators, DBTG blunted the decrease of superoxide dismutase (SOD) activity, total antioxidant capacity (T-AOC), and the increase in malondialdehyde (MDA), 8-iso-prostaglandin in lung homogenates. Treatment with DBTG restrained the expression of NOX4 compared to the model group. Present study confirms that DBTG inhibits BLM-induced PF by modulating the level of oxidative stress via suppressing NOX4. PMID:26347805

  1. Near earth magnetic disturbance in total field at high latitudes. 1: Summary of data from OGO's 2, 4, and 6

    Science.gov (United States)

    Langel, R. A.

    1973-01-01

    Variations in the total (i.e. scalar) magnetic field data from the polar orbiting OGO-2, 4, and 6 spacecraft (altitudes 400-1510 km) are summarized for invariant latitudes above 55 deg. Data from all degrees of magnetic disturbance are included. The data are presented in terms of the quantity delta B(= measured field magnitude minus the field magnitude from a spherical harmonic model of the quiet field).

  2. Evaluation of Oxidative Stress and Using a Novel Automated Method For Measurement of Total Antioxidant Status in Preeclampsia

    Directory of Open Access Journals (Sweden)

    Ebru Kale

    2006-04-01

    CONCLUSIONS: Our findings suggest that preeclampsia is related with enhanced lipid peroxidation and decreased total antioxidant response before delivery and these parameters may be related at least partly to the pathogenesis of preeclampsia. Decreased lipid peroxidation and increased total antioxidant response after delivery may suggest recov ery of preeclampsia and using a simple, rapid and reliable automated method f acilitates to ev aluate and follow up of the lev els of oxidativ e stress in preeclampsia and this novel method may be used as a routine test in clinical practice while managing preeclampsia

  3. Impact on adenosine stress cardiac magnetic resonance for recanalisation and follow up of chronic total coronary occlusions

    Energy Technology Data Exchange (ETDEWEB)

    Heyne, J.P. [Institute of Diagnostic and Interventional Radiology, Friedrich Schiller University Jena, Erlanger Allee 101, D-07740 Jena (Germany)], E-mail: Jens-Peter.Heyne@med.uni-jena.de; Goernig, M. [Clinic for Internal Medicine I, Friedrich Schiller University Jena, Erlanger Allee 101, D-07740 Jena (Germany)], E-mail: Matthias.Goernig@med.uni-jena.de; Feger, J. [Institute of Diagnostic and Interventional Radiology, Friedrich Schiller University Jena, Erlanger Allee 101, D-07740 Jena (Germany)], E-mail: Joachim.Feger@email.de; Kurrat, C. [Institute of Diagnostic and Interventional Radiology, Friedrich Schiller University Jena, Erlanger Allee 101, D-07740 Jena (Germany)], E-mail: Claudia.Kurrat@med.uni-jena.de; Werner, G.S. [Clinic for Internal Medicine I, Friedrich Schiller University Jena, Erlanger Allee 101, D-07740 Jena (Germany)], E-mail: Gerald.Werner@Klinikum-Darmstadt.de; Figulla, H.R. [Clinic for Internal Medicine I, Friedrich Schiller University Jena, Erlanger Allee 101, D-07740 Jena (Germany)], E-mail: Hans.Figulla@med.uni-jena.de; Kaiser, W.A. [Institute of Diagnostic and Interventional Radiology, Friedrich Schiller University Jena, Erlanger Allee 101, D-07740 Jena (Germany)], E-mail: Werner.Kaiser@med.uni-jena.de

    2007-09-15

    Objective: To evaluate the impact on cardiac magnetic resonance imaging (CMRI) with adenosine stress and delayed enhancement for indication and follow up after interventional recanalisation of chronic total coronary occlusions (CTOs). Material and methods: Twenty consecutive patients (15 males; 5 females; mean age 65 years) with CTO verified by cardiac catheterisation referred to CMRI. Sixteen of them got CMRI before and after coronary recanalisation. Wall motion abnormalities (WMAs), first pass perfusion with adenosine and viability were assessed using a 1.5 T MR scanner (Sonata; Siemens). CMRI results were compared with clinical classifications, the results of cardiac catheterisation and follow up angiography. Results: Sixteen patients had a successful recanalisation, 15 of the occluded coronary artery and one of collateral donor artery stenosis. After recanalisation all stress-induced progressive or new wall motion abnormalities (WMAs) of the corresponding segments and in the collateral donor territory (5 patients) and all adenosine induced perfusion defects (PD) or delay (12 patients) were regredient. 13/16 patients showed no transmural and one patient transmural delayed enhancement (DE) indicating myocardial scar. In 10/16 patients CSS grading of angina improved after recanalisation. Conclusion: After successful recanalisation of CTOs, patients with preinterventional stress-induced PDs and WMAs in viable myocardium did not display any signs of stress-induced ischemia postinterventionally. A comprehensive CMRI approach, including assessment of rest and stress WMAs, first pass perfusion and myocardial viability represents an important tool for the pre-interventional decision to recanalise CTOs and follow up.

  4. [Effect of Earth magnetic field on circadian rhythm of total antioxidant capacity of human saliva in the North].

    Science.gov (United States)

    Borisenkov, M F

    2007-01-01

    In the inhabitants of the North during increase of geomagnetic activity and during magnetic calm the decrease of amplitude of circadian rhythm of total antioxidant capacity of saliva is observed. The most favorable conditions to display the circadian rhythm are observed at Kp from 0,5 up to 2. The long residing in the North is connected to influence of irregularly varying geomagnetic activity causing disturbance of function of circadian and antioxidant systems that, probably, is one of the reasons of acceleration of process of aging at northerner and of higher risk of occurrence in them the age associated diseases.

  5. Scale-dependent response from the invariant rescaling of stress in a self-gravitating thermomechanical Earth

    Science.gov (United States)

    Watkinson, John; Patton, Regan

    2014-05-01

    It is widely known that gravitation can be accounted for via general relativity in a four-dimensional manifold called spacetime. A direct corollary of this is that the observable characteristics of any self-gravitating body in space are closely tied to its 'rheology' - how stress and deformation are related to one another. The large-scale/long-term response of terrestrial planets to loading is arguably dissipative, which can be modeled using purely viscous rheology. Evidence for this includes Earth's flattened ellipsoidal configuration, the likely result of self-gravity and rotation. On the other hand, the small scale, short-term response of solid earth materials is arguably conservative, which can be modeled using purely elastic rheology. Evidence for this includes the propagation of shear waves throughout the crust and mantle. These general observations, combined with long-term creep and attenuation of seismic signals at the longest wavelengths, seems to suggest that networks of springs, dash pots, and sliding masses, although vogue, comprise only one possible family of an otherwise infinite number of rheological models. The response of solid earth materials to loading is a scale-dependent process and involves both elasticity (strain-energy storage) and viscosity (energy dissipation). Tectonic processes are controlled by regional stratification, lithology, thermal structure, fluid content, metamorphic reactions, and deformation rates, many aspects of which are inherited through geological time. Clearly, topography and igneous activity on terrestrial planets are closely allied phenomena, consistent with global and regional isostatic balance demonstrated through gravity-topography analysis. It is reasonable to conclude that crustal stratification and igneous activity are inherent features of the Earth system, which must be predicted by any self-consistent model. We have assumed that solid earth rheology can be modeled using the differential grade-2 (DG-2) material

  6. Evaluation of nitrogen status and total chlorophyll in longkong (Aglaia dookkoo Griff. leaves under water stress using a chlorophyll meter

    Directory of Open Access Journals (Sweden)

    Sdoodee, S.

    2005-07-01

    Full Text Available A chlorophyll meter (SPAD-502 was used to assess nitrogen status and total chlorophyll in longkong leaves, leaves from twelve of 10-year-old trees grown in the experimental plot at Prince of Songkla University, Songkhla province. The relationship between SPAD-502 meter reading and nitrogen status and total chlorophyll content analyzed in the laboratory was evaluated during 8 months (May-December 2003. It was found that the trend of the relationships in each month was similar. There was no significant differenceamong regression linears of all months. The data of 8 months showed that SPAD-reading and nitrogen content, and SPAD-reading and total chlorophyll content were related in a positive manner. They were Y = 0.19X+10.10, r = 0.76** (n = 240, and Y = 0.43X-7.89, r = 0.79** (n = 400, respectively. The SPAD-502 was then used to assess total nitrogen and total chlorophyll content during imposed water stress. Fifteen 4-yearold plants were grown in pots (each pot containing 50 kg soil volume. The experiment was arranged in acompletely randomized design with 3 treatments: (1 daily watering (2 once watering on day 7 (3 no watering with 5 replications during 14 days of the experimental period. Measurements showed a continuous decrease of SPAD-reading in the treatment of no watering. On day 14, a significant difference of SPAD- reading values between the treatment of daily watering and no watering was found. Then, the values of nitrogen content and total chlorophyll were assessed by using the linear regression equations. From the result, it is suggested that the measurement by chlorophyll meter is a rapid technique for the evaluation of total chlorophyll and nitrogen status in longkong leaves during water stress.

  7. Sustained delivery of exogenous melatonin influences biomarkers of oxidative stress and total antioxidant capacity in summer-stressed anestrous water buffalo (Bubalus bubalis).

    Science.gov (United States)

    Kumar, Ashok; Mehrotra, S; Singh, G; Narayanan, K; Das, G K; Soni, Y K; Singh, Mahak; Mahla, A S; Srivastava, N; Verma, M R

    2015-06-01

    High ambient temperature during summer in tropical and subtropical countries predisposes water buffaloes (Bubalus bubalis) to develop oxidative stress having antigonadotropic and antisteroidogenic actions. Melatonin is a regulator of seasonal reproduction in photoperiodic species and highly effective antioxidant and free radical scavenger. Therefore, a study was designed to evaluate the effect of sustained-release melatonin on biomarkers of oxidative stress i.e., the serum malondialdehyde (MDA) and nitric oxide (NO), and the total antioxidant capacity (TAC). For the study, postpartum buffaloes diagnosed as summer anestrus (absence of overt signs of estrus, concurrent rectal examination, and RIA for serum progesterone) were grouped as treated (single subcutaneous injection of melatonin at 18 mg/50 kg body weight dissolved in sterilized corn oil as vehicle, n = 20) and untreated (subcutaneous sterilized corn oil, n = 8). Blood sampling for estimation of serum TAC and MDA (mmol/L) and NO (μmol/L) was carried out at 4 days of interval from 8 days before treatment till 28 days after treatment or for the ensuing entire cycle length. Results showed serum TAC concentration was higher in the treatment group with a significant (P stress resulting in the induction of cyclicity in summer-stressed anestrous buffaloes. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. The stress response and anesthetic potency of unilateral spinal anesthesia for total Hip Replacement in geriatric patients.

    Science.gov (United States)

    Zhu, Li; Tian, Chun; Li, Min; Peng, Ming-Qing; Ma, Kun-Long; Wang, Zhong-Lin; Ding, Jia-Hui; Cai, Yi

    2014-11-01

    Recently, some scholars suggested that it is important to keep a stablehemodynamic state and prevent the stress responses in geriatric patients undergoing total hip replacement (THR). We conducted this randomized prospective study to observe anesthetic potency of unilateral spinal anesthesia and stress response to it in geriatric patients during THR. We compared the effect of unilateral spinal and bilateral spinal on inhibition of stress response through measuring Norepinephrine (NE), epinephrine (E) and cortisol (CORT). Plasma concentrations of NE, E and CORT were determined in blood samples using ELISA (enzyme-linked immunosorbent assays) at three time points: To (prior to anesthesia) T1 (at the time point of skin closure), T2 (twenty-four hours after the operation). Sixty patients were randomly divided into two groups: group A (unilateral spinal anesthesia) and group B (conventional bilateral spinal anesthesia). 7.5tymg of hypobaric bupivacaine were injected into subarachnoid cavity at group A and 12mg hypobaric bupivacaine were given at group B. The onset time of sensory and motor block, loss of pinprick sensation, degree of motor block, regression of sensory and motor blocks and hemodynamic changes were also recorded. These data were used to evaluate anesthetic potency of spinal anesthesia. The results of this experiment show that unilateral spinal anesthesia can provide restriction of sensory and motor block, minimize the incidence of hypotension and prevent the stress responses undergoing THR. It is optimal anesthesia procedure for geriatric patients by rapid subarachnoid injection of small doses of bupivacaine.

  9. TIBIAL PERIPROSTHETIC FRACTURE COMBINED WITH TIBIAL STEM STRESS FRACTURE FROM TOTAL KNEE ARTHROPLASTY

    OpenAIRE

    Fonseca, Fernando; Rebelo, Edgar; Completo, Antonio

    2011-01-01

    Total knee arthroplasty complications related to the prosthetic material are very rare, except for polyethylene wear. We report the case of a 58-year-old woman who came to the emergency service of our hospital with a periprosthetic tibial fracture (Mayo Clinic type I). Careful examination showed that this fracture was concomitantly associated with a tibial stem fatigue fracture. The prosthesis and the stem were sent to an independent biomechanics laboratory for evaluation. A finite-element CA...

  10. Synthesis, structuring and characterization of rare earth oxide thin films: Modeling of the effects of stress and defects on the phase stability

    International Nuclear Information System (INIS)

    Gaboriaud, R.J.; Paumier, F.; Lacroix, B.

    2014-01-01

    This work studies the effects of the deposition parameters on the microstructure and the related residual stress in a rare earth oxide thin film. This study is focused on the yttrium sesquioxide (Y 2 O 3 ) thin films deposited on Si (100) substrates using the ion beam sputtering technique. This technique allows the control of the microstructure and the related residual stress in the thin films by monitoring the energy of the argon beam used in the deposition process. Measurements of the stresses within the oxide layer were performed by the X-ray diffraction-sin 2 Ψ method. The results show that the classic model of a pure biaxial in-plane model of stress, generally proposed in thin films, is not satisfying. A model that includes a hydrostatic stress due to the crystalline defects generated during the deposition process and a biaxial stress called a fixation stress, gives a good agreement with the experimental results. This modeling of the residual stress, based on nanometer-scale inclusions (point, extended defects) inducing a hydrostatic stress field, leads to a quantitative analysis of the nature and the concentration of the defects. This work shows results that establish a relationship between residual stress, defects and non-equilibrium phase stabilization during growth. - Highlights: • Microstructure of Y 2 O 3 thin films • Measurements of residual stresses in the thin films • Modeling of a triaxial residual stress state • Stress-induced stabilization of non-equilibrium phase

  11. Resuspended contaminated sediments cause sublethal stress to oysters: A biomarker differentiates total suspended solids and contaminant effects.

    Science.gov (United States)

    Edge, Katelyn J; Dafforn, Katherine A; Simpson, Stuart L; Ringwood, Amy H; Johnston, Emma L

    2015-06-01

    Resuspended contaminated sediments represent an important route of contaminant exposure for aquatic organisms. During resuspension events, filter-feeding organisms are exposed to contaminants, in both the dissolved form (at the gills) and the particulate form (in the digestive system). In addition, these organisms must manage the physical stress associated with an increase in total suspended solids (TSS). To date, few studies have experimentally compared the contributions to biological stress of contaminated and clean suspended solids. The authors mixed field-collected sediments (cellular biomarkers (lysosomal membrane stability, lipid peroxidation, and glutathione) were measured to evaluate sublethal toxicity. Lysosomal membrane stability was the most sensitive biomarker for distinguishing effects from resuspended contaminated sediments, as increasing amounts of contaminated TSS increased lysosomal membrane destabilization. The authors' results illustrate the importance of considering contaminant exposures from resuspended sediments when assessing the toxicity of contaminants to aquatic organisms. © 2015 SETAC.

  12. [Characterization of kale (Brassica oberacea var acephala) under thallium stress by in situ attenuated total reflection FTIR].

    Science.gov (United States)

    Yao, Yan; Zhang, Ping; Wang, Zhen-Chun; Chen, Yong-Heng

    2009-01-01

    The experiment was designed based on consumption of carbon dioxide through the photosynthesis of Brassica oberacea var acephala leaf, and the photosynthesis of kale leaf under thallium stress was investigated by in situ attenuated total reflection FTIR (in situ ATR-FTIR). The ATR-FTIR showed that the absorption peaks of leaves had no obvious difference between plants growing in thallium stress soil and plants growing in non-thallium pollution soil, and the strong peaks at 3,380 cm(-1) could be assigned to the absorption of water, carbohydrate, protein or amide; the strong peaks at 2,916 and 2,850 cm(-1) assigned to the absorption of carbohydrate or aliphatic compound; the peaks at 1,640 cm(-1) assigned to the absorption of water. However, as detected by the in situ ATR-FTIR, the double peaks (negative peaks) at 2,360 and 2,340 cm(-1) that are assigned to the absorption of CO2 appeared and became high gradually. It was showed that kale was carrying photosynthesis. At the same time, the carbon dioxide consumption speed of leaf under thallium stress was obviously larger than that of the blank It was expressed that photosynthesis under thallium stress was stronger than the blank All these represented that kale had certain tolerance to the heavy metal thallium. Meanwhile, the carbon dioxide consumption of grown-up leaf was more than that of young leaf whether or not under thallium stress. It was also indicated that the intensity of photosynthesis in grown-up leaf is higher than that in young leaf.

  13. Quantification of particle-induced inflammatory stress response: a novel approach for toxicity testing of earth materials

    Directory of Open Access Journals (Sweden)

    Harrington Andrea D

    2012-04-01

    Full Text Available Abstract Background Reactive oxygen species (ROS are vital regulators of many cellular functions in the body. The intracellular ROS concentration is highly regulated by a balance between pro-oxidants and anti-oxidants. A chronic excess of pro-oxidants leads to elevated ROS concentrations and inflammation, possibly initiating or enhancing disease onset. Mineral-induced generation of ROS, the role of minerals in upregulating cellular ROS, and their role in the development of several occupational diseases are now widely recognized. However, there is no standard protocol to determine changes in ROS production in cells after exposure to mineral dust or earth materials in general. In this study, a new method for determining the degree of cellular toxicity (i.e., cytotoxicity of particles is described that will help bridge the gap in knowledge. Results By measuring the production of ROS and the viability of cells, an inflammatory stress response (ISR indicator is defined. This approach normalizes the ROS upregulation with respect to the number of viable cells at the time of measurement. We conducted experiments on a series of minerals and soils that represent materials that are inert (i.e., glass beads, anatase, and a soil with low trace element content, moderately reactive (i.e., soil with high trace element content, and highly reactive (i.e., pyrite. Inert materials generated the lowest ISR, averaging 350% compared to the control. Acid washed pyrite produced the highest ISR (1,100 fold higher than the control. The measurements conducted as a function of time showed a complex response. Most materials showed an increase in ISR with particle loading. Conclusions The amount of cellularly generated ROS and cell viability combined provide a better understanding of particle-induced oxidative stress. The results indicate that some earth materials may solicit an initial burst of ROS, followed by a second phase in which cell viability decreases and ROS

  14. In-situ stress measurements in the earth's crust in the eastern United States

    International Nuclear Information System (INIS)

    Rundle, T.A.; Singh, M.M.; Baker, C.H.

    1987-04-01

    The US Nuclear Regulatory Commission requires that the design basis for vibratory ground motion should be determined through correlation of seismicity with tectonic structures or provinces (10CFR100, Appendix A). Such criteria are difficult to apply in the eastern United States, which experiences persistent low level seismicity, with occasional moderate to large earthquakes. This report presents the results of in-situ stress measurements conducted towards reducing this uncertainty at three (3) seismically active sites in the region, namely, near Moodus, Connecticut, around the Ramapo fault zone in New York and New Jersey, and in central Virginia. As far as possible, at each location one bore hole was drilled close to the ''apparent'' epicenter of the seismic activity and one outside the ''known'' seismic zone, so that the data obtained could be compared. The results obtained were very consistent both as to magnitude and direction. No attempt was made to correlate the in-situ stress measurements with the tectonic setting or seismic activity, since this was beyond the scope of this project. Extensive appendices report experimental data. 35 refs

  15. Physiological Indices of Stress Prior to and Following Total Knee Arthroplasty Predict the Occurrence of Severe Post-Operative Pain.

    Science.gov (United States)

    Cremeans-Smith, Julie K; Greene, Kenneth; Delahanty, Douglas L

    2016-05-01

    The severe pain and disability associated with osteoarthritis often motivate individuals to undergo arthroplastic surgery. However, a significant number of surgical patients continue to experience pain following surgery. Prior research has implicated both the hypothalamic-pituitary-adrenal (HPA) axis and sympathetic nervous system (SNS) in the sensitization of pain receptors and chronic pain conditions. This study uses a prospective, observational, cohort design to examine whether physiological stress responses before and after surgery could predict post-operative pain severity. Participants included 110 patients undergoing total knee arthroplasty. Physiological indices of stress included the measurement of catecholamine and cortisol levels in 15-hour urine samples collected prior to and 1 month following surgery, as well as in-hospital heart rate and blood pressure (before and after surgery), which were abstracted from medical records. Patients completed the pain subscale of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) [Bellamy et al., J Orthop Rheumatol 1: , 95 (1988)] 2.5 weeks prior to surgery and at a 3-month follow-up. Contrary to expectations, lower stress hormone levels at baseline were related to more severe post-operative pain. Data at later time points, however, supported our hypothesis: cardiovascular tone shortly before surgery and urinary levels of epinephrine 1 month following surgery were positively related to pain severity 3 months later. Results suggest that the occurrence of post-operative pain can be predicted on the basis of stress physiology prior to and following arthroplastic surgery. © 2015 American Academy of Pain Medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  16. Seasonal and spatial variations of rare earth elements in rainwaters, river waters and total suspended particles in air in South Korea

    International Nuclear Information System (INIS)

    Ryu, J.S.; Lee, K.S.; Lee, S.G.; Lee, D.; Chang, H.W.

    2007-01-01

    In order to investigate the seasonal and spatial variations of rare earth element (REE) concentrations in natural waters in the central part of South Korea, rain and river waters were collected during 2003-2004. Total suspended particles (TSP) in air were also sampled to investigate the effect of the Asian dust (the Yellow sand) on the chemistry of rainwaters. All samples showed that the absolute concentrations of the light REEs (LREEs) were higher than those of the heavy REEs (HREEs). The post-Archean Australian shale (PAAS)-normalized REE patterns indicate that the REEs in TSP and rainwaters were affected by Asian dust and anthropogenic contaminant, whereas those of river waters were mainly controlled by the geology of their drainage basin and seasonal changes in water regime. The calculated fluxes and yields of total REEs (REEs plus Y) in the South Han River were much greater than those in the North Han River due to the more widespread distribution of sedimentary rocks in the drainage area and more efficient chemical weathering

  17. The Influence of Oral Carbohydrate Solution Intake on Stress Response before Total Hip Replacement Surgery during Epidural and General Anaesthesia.

    Science.gov (United States)

    Çeliksular, M Cem; Saraçoğlu, Ayten; Yentür, Ercüment

    2016-06-01

    The effects of oral carbohydrate solutions, ingested 2 h prior to operation, on stress response were studied in patients undergoing general or epidural anaesthesia. The study was performed on 80 ASA I-II adult patients undergoing elective total hip replacement, which were randomized to four groups (n=20). Group G patients undergoing general anaesthesia fasted for 8 h preoperatively; Group GN patients undergoing general anaesthesia drank oral carbohydrate solutions preoperatively; Group E patients undergoing epidural anaesthesia fasted for 8 h and Group EN patients undergoing epidural anaesthesia drank oral carbohydrate solutions preoperatively. Groups GN and EN drank 800 mL of 12.5% oral carbohydrate solution at 24:00 preoperatively and 400 mL 2 h before the operation. Blood samples were taken for measurements of glucose, insulin, cortisol and IL-6 levels. The effect of preoperative oral carbohydrate ingestion on blood glucose levels was not significant. Insulin levels 24 h prior to surgery were similar; however, insulin levels measured just before surgery were 2-3 times higher in groups GN and EN than in groups G and E. Insulin levels at the 24(th) postoperative hour in epidural groups were increased compared to those at basal levels, although general anaesthesia groups showed a decrease. From these measurements, only the change in Group EN was statistically significant (poral carbohydrate nutrition did not reveal a significant effect on surgical stress response.

  18. Recent approaches to the total synthesis of phytoprostanes, isoprostanes and neuroprostanes as important products of lipid oxidative stress and biomarkers of disease

    Czech Academy of Sciences Publication Activity Database

    Jahn, Emanuela; Durand, T.; Galano, J. M.; Jahn, Ullrich

    2014-01-01

    Roč. 108, č. 4 (2014), s. 301-319 ISSN 0009-2770 Institutional support: RVO:61388963 Keywords : lipids * oxidative stress * phytoprostanes * isoprostanes * neuroprostanes * total synthesis Subject RIV: CC - Organic Chemistry Impact factor: 0.272, year: 2014

  19. Improving stress shielding following total hip arthroplasty by using a femoral stem made of β type Ti-33.6Nb-4Sn with a Young's modulus gradation

    NARCIS (Netherlands)

    Yamako, Go; Janssen, Dennis; Hanada, Shuji; Anijs, Thomas; Ochiai, Kiyohide; Totoribe, Koji; Chosa, Etsuo; Verdonschot, Nico

    2017-01-01

    Stress shielding-related bone loss occurs after total hip arthroplasty because the stiffness of metallic implants differs from that of the host femur. Although reducing stem stiffness can ameliorate the bone resorption, it increases stress at the bone–implant interface and can inhibit fixation. To

  20. Effects of deglaciation on the crustal stress field and implications for endglacial faulting: A parametric study of simple Earth and ice models

    International Nuclear Information System (INIS)

    Lund, Bjoern

    2005-03-01

    The large faults of northern Scandinavia, hundreds of kilometres long and with offsets of more than 10 m, are inferred to be the result of major earthquakes triggered by the retreating ice sheet some 9,000 years ago. In this report we have studied a number of parameters involved in quantitative modelling of glacial isostatic adjustment (GIA) in order to illustrate how they affect stress, displacement and fault stability during deglaciation. Using a variety of reference models, we have verified that our modelling approach, a finite element analysis scheme with proper adjustments for the requirements of GIA modelling, performs satisfactory. The size of the model and the density of the grid have been investigated in order to be able to perform high resolution modelling in reasonable time. This report includes studies of both the ice and earth models. We have seen that the steeper the ice edge is, the more concentrated is the deformation around the edge and consequently shear stress localizes with high magnitudes around the ice edge. The temporal evolution of height and basal extent of the ice is very important for the response of the earth model, and we have shown that the last stages of ice retreat can cause fault instability over a large lateral region. The effect on shear stress and vertical displacement by variations in Earth model parameters such as stiffness, viscosity, density, compressibility and layer thickness was investigated. More complicated geometries, such as multiple layers and lateral layer thickness variations, were also studied. We generally find that these variations have more effect on the shear stress distributions than on the vertical displacement distributions. We also note that shear stress magnitude is affected more than the spatial shape of the shear stress distribution. Fault stability during glaciation/deglaciation was investigated by two different variations on the Mohr-Coulomb failure criterion. The stability of a fault in a stress field

  1. Effects of deglaciation on the crustal stress field and implications for endglacial faulting: A parametric study of simple Earth and ice models

    Energy Technology Data Exchange (ETDEWEB)

    Lund, Bjoern [Uppsala Univ. (Sweden). Dept. of Earth Sciences

    2005-03-01

    The large faults of northern Scandinavia, hundreds of kilometres long and with offsets of more than 10 m, are inferred to be the result of major earthquakes triggered by the retreating ice sheet some 9,000 years ago. In this report we have studied a number of parameters involved in quantitative modelling of glacial isostatic adjustment (GIA) in order to illustrate how they affect stress, displacement and fault stability during deglaciation. Using a variety of reference models, we have verified that our modelling approach, a finite element analysis scheme with proper adjustments for the requirements of GIA modelling, performs satisfactory. The size of the model and the density of the grid have been investigated in order to be able to perform high resolution modelling in reasonable time. This report includes studies of both the ice and earth models. We have seen that the steeper the ice edge is, the more concentrated is the deformation around the edge and consequently shear stress localizes with high magnitudes around the ice edge. The temporal evolution of height and basal extent of the ice is very important for the response of the earth model, and we have shown that the last stages of ice retreat can cause fault instability over a large lateral region. The effect on shear stress and vertical displacement by variations in Earth model parameters such as stiffness, viscosity, density, compressibility and layer thickness was investigated. More complicated geometries, such as multiple layers and lateral layer thickness variations, were also studied. We generally find that these variations have more effect on the shear stress distributions than on the vertical displacement distributions. We also note that shear stress magnitude is affected more than the spatial shape of the shear stress distribution. Fault stability during glaciation/deglaciation was investigated by two different variations on the Mohr-Coulomb failure criterion. The stability of a fault in a stress field

  2. Differences in the stress distribution in the distal femur between patellofemoral joint replacement and total knee replacement: a finite element study

    Directory of Open Access Journals (Sweden)

    van Jonbergen Hans-Peter W

    2012-06-01

    Full Text Available Abstract Background Patellofemoral joint replacement is a successful treatment option for isolated patellofemoral osteoarthritis. However, results of later conversion to total knee replacement may be compromised by periprosthetic bone loss. Previous clinical studies have demonstrated a decrease in distal femoral bone mineral density after patellofemoral joint replacement. It is unclear whether this is due to periprosthetic stress shielding. The main objective of the current study was to evaluate the stress shielding effect of prosthetic replacement with 2 different patellofemoral prosthetic designs and with a total knee prosthesis. Methods We developed a finite element model of an intact patellofemoral joint, and finite element models of patellofemoral joint replacement with a Journey PFJ prosthesis, a Richards II prosthesis, and a Genesis II total knee prosthesis. For each of these 4 finite element models, the average Von Mises stress in 2 clinically relevant regions of interest were evaluated during a simulated squatting movement until 120 degrees of flexion. Results During deep knee flexion, in the anterior region of interest, the average Von Mises stress with the Journey PFJ design was comparable to the physiological knee, while reduced by almost 25% for both the Richards II design and the Genesis II total knee joint replacement design. The average Von Mises stress in the supracondylar region of interest was similar for both patellofemoral prosthetic designs and the physiological model, with slightly lower stress for the Genesis II design. Conclusions Patellofemoral joint replacement results in periprosthetic stress-shielding, although to a smaller degree than in total knee replacement. Specific patellofemoral prosthetic design properties may result in differences in femoral stress shielding.

  3. Differences in the stress distribution in the distal femur between patellofemoral joint replacement and total knee replacement: a finite element study

    Science.gov (United States)

    2012-01-01

    Background Patellofemoral joint replacement is a successful treatment option for isolated patellofemoral osteoarthritis. However, results of later conversion to total knee replacement may be compromised by periprosthetic bone loss. Previous clinical studies have demonstrated a decrease in distal femoral bone mineral density after patellofemoral joint replacement. It is unclear whether this is due to periprosthetic stress shielding. The main objective of the current study was to evaluate the stress shielding effect of prosthetic replacement with 2 different patellofemoral prosthetic designs and with a total knee prosthesis. Methods We developed a finite element model of an intact patellofemoral joint, and finite element models of patellofemoral joint replacement with a Journey PFJ prosthesis, a Richards II prosthesis, and a Genesis II total knee prosthesis. For each of these 4 finite element models, the average Von Mises stress in 2 clinically relevant regions of interest were evaluated during a simulated squatting movement until 120 degrees of flexion. Results During deep knee flexion, in the anterior region of interest, the average Von Mises stress with the Journey PFJ design was comparable to the physiological knee, while reduced by almost 25% for both the Richards II design and the Genesis II total knee joint replacement design. The average Von Mises stress in the supracondylar region of interest was similar for both patellofemoral prosthetic designs and the physiological model, with slightly lower stress for the Genesis II design. Conclusions Patellofemoral joint replacement results in periprosthetic stress-shielding, although to a smaller degree than in total knee replacement. Specific patellofemoral prosthetic design properties may result in differences in femoral stress shielding. PMID:22704638

  4. Elastic stress transmission and transformation (ESTT) by confined liquid: A new mechanics for fracture in elastic lithosphere of the earth

    Science.gov (United States)

    Xu, Xing-Wang; Peters, Stephen; Liang, Guang-He; Zhang, Bao-Lin

    2016-01-01

    We report on a new mechanical principle, which suggests that a confined liquid in the elastic lithosphere has the potential to transmit a maximum applied compressive stress. This stress can be transmitted to the internal contacts between rock and liquid and would then be transformed into a normal compressive stress with tangential tensile stress components. During this process, both effective compressive normal stress and tensile tangential stresses arise along the liquid–rock contact. The minimum effective tensile tangential stress causes the surrounding rock to rupture. Liquid-driven fracture initiates at the point along the rock–liquid boundary where the maximum compressive stress is applied and propagates along a plane that is perpendicular to the minimum effective tensile tangential stress and also is perpendicular to the minimum principal stress.

  5. The total triterpenoid saponins of Xanthoceras sorbifolia improve learning and memory impairments through against oxidative stress and synaptic damage.

    Science.gov (United States)

    Ji, Xue-Fei; Chi, Tian-Yan; Liu, Peng; Li, Lu-Yi; Xu, Ji-Kai; Xu, Qian; Zou, Li-Bo; Meng, Da-Li

    2017-02-15

    X. sorbifolia is a widely cultivated ecologicalcrop in the north of China which is used to produce biodiesel fuel. It also possesses special medicinal value and has attracted keen interests of researchers to explore its bioactivity. To extract the total triterpenoid saponins from the husk of X. sorbifolia (TSX) and investigate its effects on Alzheimer's disease (AD). TSX was prepared via modern extraction techniques. Its effects on two AD animal models, as well as the preliminary mechanism were investigated comprehensively. The behavioral experiments including Y maze test, Morris water maze test and passive avoidance test were performed to observe the learning and memory abilities of the animals. ELISA assays, transmission electron microscope observation and Western blotting were employed in mechanism study. TSX, the main composition of X. sorbifolia, accounted for 88.77% in the plant material. It could significantly increase the spontaneous alternation in Y maze test (F (6, 65)=3.209, Plearning and memory. The preliminary mechanism might associate with its protection effects against oxidative stress damage, cholinergic system deficiency and synaptic damage. TSX are perfectly suitable for AD patients as medicine or functional food, which would be a new candidate to treat AD. Copyright © 2016 Elsevier GmbH. All rights reserved.

  6. One- and multistage total strain and stress-controlled fatigue tests with a steel of type 42 CrMo 4 subject to varied residual and mean stress loading. Final report

    International Nuclear Information System (INIS)

    Macherauch, E.; Schulze, V.

    1995-01-01

    Work under this research project covered tests with the quenched and tempered steel 42 CrMo 4 to which one- and two-stage tension-compression fatigue stresses were applied with varying mean loads, under conditions of nominal stress and total strain control. Shot peening was used to induce various microstructural conditions in the material at the surface and near below. Softening in the material was observed to be a continuous process, and the steel showed no stabilised, cyclic deformation behaviour. The cyclic stress-strain curve measured with equal stress amplitudes and total strain control applied shows higher plastic strain amplitudes than that measured with nominal stresses. The fatigue behaviour under two-stage loading depends on the chosen sequence of loads applied, the testing periods, and the overall testing procedure, so that there is no way of deriving data for two-stage testing procedures from single-stage test results. (orig.) [de

  7. Stress

    Science.gov (United States)

    ... can be life-saving. But chronic stress can cause both physical and mental harm. There are at least three different types of stress: Routine stress related to the pressures of work, family, and other daily responsibilities Stress brought about ...

  8. Earth Rotation

    Science.gov (United States)

    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.

  9. Increased risk of attempted suicide in Australian veterans is associated with total and permanent incapacitation, unemployment and posttraumatic stress disorder severity.

    Science.gov (United States)

    Kerr, Katelyn; Romaniuk, Madeline; McLeay, Sarah; Khoo, Andrew; Dent, Michael T; Boshen, Mark

    2018-06-01

    Military veterans have higher rates of suicidality and completed suicides compared to the general population. Previous research has demonstrated suicidal behaviour is higher in US combat veterans who are younger, suffer from posttraumatic stress disorder, depression and anxiety and score lower on measures of health. However, research on predictors of suicide for Australian veterans is limited. The aim of this study was to identify significant demographic and psychological differences between veterans with posttraumatic stress disorder who had attempted suicide and those with posttraumatic stress disorder who had not, as well as determine predictors of suicide attempts within an Australian cohort. A retrospective analysis was conducted on 229 ex-service personnel diagnosed with posttraumatic stress disorder who had attended a Military Service Trauma Recovery Day Program as outpatients at Toowong Private Hospital from 2007 to 2014. Patients completed a battery of mental health self-report questionnaires assessing symptoms of posttraumatic stress disorder, alcohol use, anger, depression, anxiety and quality of life. Demographic information and self-reported history of suicide attempts were also recorded. Results indicated the average age was significantly lower, and the rates of posttraumatic stress disorder, anger, anxiety and depression symptoms were significantly higher in those veterans with history of a suicide attempt. Multivariate logistic regression analyses indicated posttraumatic stress disorder symptom severity, unemployment or total and permanent incapacity pension status significantly predicted suicide attempt history. Among a cohort of Australian veterans with posttraumatic stress disorder, psychopathology severity, unemployment and total and permanent incapacity status are significantly associated with suicidality. This study highlights the importance of early identification of posttraumatic stress disorder and psychopathology, therapeutic and social

  10. Post-Cam Design and Contact Stress on Tibial Posts in Posterior-Stabilized Total Knee Prostheses: Comparison Between a Rounded and a Squared Design.

    Science.gov (United States)

    Watanabe, Toshifumi; Koga, Hideyuki; Horie, Masafumi; Katagiri, Hiroki; Sekiya, Ichiro; Muneta, Takeshi

    2017-12-01

    The post-cam mechanism in posterior stabilized (PS) prostheses plays an important role in total knee arthroplasty (TKA). The purpose of this study is to clarify the difference of the contact stress on the tibial post between a rounded post-cam design and a squared design during deep knee flexion and at hyperextension using the three-dimensional (3D) finite element models. We created 2 types of 3D, finite element models of PS prostheses (types A and B), whose surfaces were identical except for the post-cam geometries: type A has a rounded post-cam design, while type B has a squared design. Both types have a similar curved-shape intercondylar notch of the femoral component. Stress distributions, peak contact stresses, and contact areas on the tibial posts at 90°, 120°, and 150° flexion with/without 10° tibial internal rotation and at 10° hyperextension were compared between the 2 models. Type B demonstrated more concentrated stress distribution compared to type A. The peak contact stresses were similar in both groups during neutral flexion; however, the stresses were much higher in type B during flexion with 10° rotation and at hyperextension. The higher peak contact stresses corresponded to the smaller contact areas in the tibial post. A rounded post-cam design demonstrated less stress concentration during flexion with rotation and at hyperextension compared with a squared design. The results would be useful for development of implant designs and prediction of the contact stress on the tibial post in PS total knee arthroplasty. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. TOMS/Earth-Probe Total Ozone Aerosol Index UV-Reflectivity UV-B Erythemal Irradiance Daily L3 Global 1x1.25 deg V008

    Data.gov (United States)

    National Aeronautics and Space Administration — The Total Ozone Mapping Spectrometer (TOMS) version 8 daily global gridded data consist of total column ozone, aerosol index, Lambertian effective surface...

  12. The transmission of stress to grafted bone inside a titanium mesh cage used in anterior column reconstruction after total spondylectomy: a finite-element analysis.

    Science.gov (United States)

    Akamaru, Tomoyuki; Kawahara, Norio; Sakamoto, Jiro; Yoshida, Akira; Murakami, Hideki; Hato, Taizo; Awamori, Serina; Oda, Juhachi; Tomita, Katsuro

    2005-12-15

    A finite-element study of posterior alone or anterior/posterior combined instrumentation following total spondylectomy and replacement with a titanium mesh cage used as an anterior strut. To compare the effect of posterior instrumentation versus anterior/posterior instrumentation on transmission of the stress to grafted bone inside a titanium mesh cage following total spondylectomy. The most recent reconstruction techniques following total spondylectomy for malignant spinal tumor include a titanium mesh cage filled with autologous bone as an anterior strut. The need for additional anterior instrumentation with posterior pedicle screws and rods is controversial. Transmission of the mechanical stress to grafted bone inside a titanium mesh cage is important for fusion and remodeling. To our knowledge, there are no published reports comparing the load-sharing properties of the different reconstruction methods following total spondylectomy. A 3-dimensional finite-element model of the reconstructed spine (T10-L4) following total spondylectomy at T12 was constructed. A Harms titanium mesh cage (DePuy Spine, Raynham, MA) was positioned as an anterior replacement, and 3 types of the reconstruction methods were compared: (1) multilevel posterior instrumentation (MPI) (i.e., posterior pedicle screws and rods at T10-L2 without anterior instrumentation); (2) MPI with anterior instrumentation (MPAI) (i.e., MPAI [Kaneda SR; DePuy Spine] at T11-L1); and (3) short posterior and anterior instrumentation (SPAI) (i.e., posterior pedicle screws and rods with anterior instrumentation at T11-L1). The mechanical energy stress distribution exerted inside the titanium mesh cage was evaluated and compared by finite-element analysis for the 3 different reconstruction methods. Simulated forces were applied to give axial compression, flexion, extension, and lateral bending. In flexion mode, the energy stress distribution in MPI was higher than 3.0 x 10 MPa in 73.0% of the total volume inside

  13. Influence of alkali metal oxides and alkaline earth metal oxides on the mitigation of stress corrosion cracking in CANDU fuel sheathing

    Energy Technology Data Exchange (ETDEWEB)

    Metzler, J.; Ferrier, G.A.; Farahani, M.; Chan, P.K.; Corcoran, E.C., E-mail: Joseph.Metzler@rmc.ca [Royal Military College of Canada, Kingston, ON (Canada)

    2015-07-01

    Stress corrosion cracking (SCC)can cause failures of CANDU Zircaloy-4 fuel sheathing. The process occurs when a corrosive element (i.e.,iodine) interacts with a susceptible material that is under sufficient strain at a high temperature. Currently, there is an ongoing effort to improve SCC mitigation strategies for future iterations of CANDU reactors. A potential mechanism for SCC mitigation involves utilizing alkali metal oxides and alkaline earth metal oxides that will sequester corrosive iodine while actively repairing a protective oxide layer on the sheath. SCC tests performed with sodium oxide (Na{sub 2}O) and calcium oxide (CaO) have shown to decrease significantly the sheath degradation. (author)

  14. Responses of antioxidant systems after exposition to rare earths and their role in chilling stress in common duckweed (Lemna minor L.): a defensive weapon or a boomerang?

    Science.gov (United States)

    Ippolito, M P; Fasciano, C; d'Aquino, L; Morgana, M; Tommasi, F

    2010-01-01

    Extensive agriculture application of rare earth elements (REEs) in Far East countries might cause spreading of these metals in aquatic and terrestrial ecosystems, thus inducing a growing concern about their environmental impact. In this work the effects of a mix of different REE nitrate (RE) and of lanthanum nitrate (LA) on catalase and antioxidant systems involved in the ascorbate-glutathione cycle were investigated in common duckweed Lemna minor L. The results indicated that L. minor shows an overall good tolerance to the presence of REEs in the media. Treatments at concentrations up to 5 mM RE and 5 mM LA did not cause either visible symptoms on plants or significant effects on reactive oxygen species (ROS) production, chlorophyll content, and lipid peroxidation. Toxic effects were observed after 5 days of exposition to 10 mM RE and 10 mM LA. A remarkable increase in glutathione content as well as in enzymatic antioxidants was observed before the appearance of the stress symptoms in treated plants. Duckweed plants pretreated with RE and LA were also exposed to chilling stress to verify whether antioxidants variations induced by RE and LA improve plant resistance to the chilling stress. In pretreated plants, a decrease in ascorbate and glutathione redox state and in chlorophyll content and an increase in lipid peroxidation and ROS production levels were observed. The use of antioxidant levels as a stress marker for monitoring REE toxicity in aquatic ecosystems by means of common duckweed is discussed.

  15. 78 FR 59791 - Annual Company-Run Stress Tests at Banking Organizations With Total Consolidated Assets of More...

    Science.gov (United States)

    2013-09-30

    ... bank on its Consolidated Financial Statements for Bank Holding Companies (FR Y-9C) or Consolidated... companies with $50 billion or more in total consolidated assets and any non-bank financial companies... with total consolidated assets of $50 billion or more and nonbank financial companies supervised by the...

  16. [Stress analysis of femoral stems in cementless total hip arthroplasty by two-dimensional finite element method using boundary friction layer].

    Science.gov (United States)

    Oomori, H; Imura, S; Gesso, H

    1992-04-01

    To develop stem design achieving primary fixation of stems and effective load transfer to the femur, we studied stress analysis of stems in cementless total hip arthroplasty by two-dimensional finite element method using boundary friction layer in stem-bone interface. The results of analyses of stem-bone interface stresses and von Mises stresses at the cortical bones indicated that ideal stem design features would be as follows: 1) Sufficient length, with the distal end extending beyond the isthmus region. 2) Maximum possible width, to contact the cortical bones in the isthmus region. 3) No collars but a lateral shoulder at the proximal portion. 4) A distal tip, to contact the cortical bones at the distal portion.

  17. The effect of heat stress and other factors on total body water and some blood constituents in lactating goats

    International Nuclear Information System (INIS)

    Haggag, A.M.A.

    1988-01-01

    Goats mostly live in the desert or semidesert areas in egypt. Such areas are under adverse environmental conditions. They represent indispensable source of meat and milk for the natives of these areas . Few studies are carried out on goats in connection with their biochemical and physiological response to the high environmental temperature. The present investigation carried out was constructed to study the state of heat stress(35 C and 25% ) in nine Baladi lactating goats as compared with the reactions under mild conditions (15 C and 50% RH). Animals were Kept under each of these controlled conditions for 7 days - eight hours / day. The study included blood haemoglobin level, erythrocyte count, haematocrit value, serum activity of alkaline and acid phosphatases, creatinine, urea and prolactin. The effect of heat stress on body water content and water turnover rate using tritiated water diulation technique was studied

  18. Ipsilateral stress fracture of the proximal fibula after total knee arthroplasty in a patient with severe valgus knee deformity on a background of Rheumatoid arthritis

    Directory of Open Access Journals (Sweden)

    Hirokazu Takai

    Full Text Available Introduction: Previous studies have reported a lower extremity stress fracture after total knee arthroplasty (TKA. However, a fibular fracture after TKA is quite rare. We report a case of proximal fibula fracture after TKA in a patient with rheumatoid arthritis (RA. Presentation of case: A 45 year old woman with RA had severe knee and foot pain with an antalgic gait disturbance. There was a significant joint deformity in many of lower limb joints. Interval bilateral TKAs were performed two weeks apart. Right TKA was performed using a constraint-type prosthesis, through lateral parapatellar approach. Left TKA was performed using a posterior-stabilized (PS prosthesis through the more commonly employed, medial parapatellar approach. Seven weeks after the right TKA, the patient was found to have an atraumatic proximal fibular fracture. The fracture went on to heal conservatively. Discussion: The fracture was considered to have occurred after the TKA. The callus appeared eleven weeks after the TKA. The factors that contributed to the fracture were thought to be overload of the fragile bone secondarily to disuse osteopaenia, RA or potentially the significant valgus malalignment correction. The surgical approach, the implant or implantation or the persisting joint deformity, were thought to be contributing factors to the aetiology of the stress fracture. The resultant change in clinical outcome/course is outlined in this case report. Conclusion: A stress fracture of the proximal fibula has the potential in the aetiology of may cause other stress fractures, joint other instability, and/or malalignment of the total lower extremity. Keywords: Stress fracture, Insufficiency fracture, Total knee arthroplasty, Fibula fracture, Valgus deformity, Rheumatoid arthritis

  19. Fully porous 3D printed titanium femoral stem to reduce stress-shielding following total hip arthroplasty.

    Science.gov (United States)

    Arabnejad, Sajad; Johnston, Burnett; Tanzer, Michael; Pasini, Damiano

    2017-08-01

    Current hip replacement femoral implants are made of fully solid materials which all have stiffness considerably higher than that of bone. This mechanical mismatch can cause significant bone resorption secondary to stress shielding, which can lead to serious complications such as peri-prosthetic fracture during or after revision surgery. In this work, a high strength fully porous material with tunable mechanical properties is introduced for use in hip replacement design. The implant macro geometry is based off of a short stem taper-wedge implant compatible with minimally invasive hip replacement surgery. The implant micro-architecture is fine-tuned to locally mimic bone tissue properties which results in minimum bone resorption secondary to stress shielding. We present a systematic approach for the design of a 3D printed fully porous hip implant that encompasses the whole activity spectrum of implant development, from concept generation, multiscale mechanics of porous materials, material architecture tailoring, to additive manufacturing, and performance assessment via in vitro experiments in composite femurs. We show that the fully porous implant with an optimized material micro-structure can reduce the amount of bone loss secondary to stress shielding by 75% compared to a fully solid implant. This result also agrees with those of the in vitro quasi-physiological experimental model and the corresponding finite element model for both the optimized fully porous and fully solid implant. These studies demonstrate the merit and the potential of tuning material architecture to achieve a substantial reduction of bone resorption secondary to stress shielding. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1774-1783, 2017. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  20. Quantitative monitoring of sucrose, reducing sugar and total sugar dynamics for phenotyping of water-deficit stress tolerance in rice through spectroscopy and chemometrics

    Science.gov (United States)

    Das, Bappa; Sahoo, Rabi N.; Pargal, Sourabh; Krishna, Gopal; Verma, Rakesh; Chinnusamy, Viswanathan; Sehgal, Vinay K.; Gupta, Vinod K.; Dash, Sushanta K.; Swain, Padmini

    2018-03-01

    In the present investigation, the changes in sucrose, reducing and total sugar content due to water-deficit stress in rice leaves were modeled using visible, near infrared (VNIR) and shortwave infrared (SWIR) spectroscopy. The objectives of the study were to identify the best vegetation indices and suitable multivariate technique based on precise analysis of hyperspectral data (350 to 2500 nm) and sucrose, reducing sugar and total sugar content measured at different stress levels from 16 different rice genotypes. Spectral data analysis was done to identify suitable spectral indices and models for sucrose estimation. Novel spectral indices in near infrared (NIR) range viz. ratio spectral index (RSI) and normalised difference spectral indices (NDSI) sensitive to sucrose, reducing sugar and total sugar content were identified which were subsequently calibrated and validated. The RSI and NDSI models had R2 values of 0.65, 0.71 and 0.67; RPD values of 1.68, 1.95 and 1.66 for sucrose, reducing sugar and total sugar, respectively for validation dataset. Different multivariate spectral models such as artificial neural network (ANN), multivariate adaptive regression splines (MARS), multiple linear regression (MLR), partial least square regression (PLSR), random forest regression (RFR) and support vector machine regression (SVMR) were also evaluated. The best performing multivariate models for sucrose, reducing sugars and total sugars were found to be, MARS, ANN and MARS, respectively with respect to RPD values of 2.08, 2.44, and 1.93. Results indicated that VNIR and SWIR spectroscopy combined with multivariate calibration can be used as a reliable alternative to conventional methods for measurement of sucrose, reducing sugars and total sugars of rice under water-deficit stress as this technique is fast, economic, and noninvasive.

  1. Stress

    Science.gov (United States)

    ... taking care of an aging parent. With mental stress, the body pumps out hormones to no avail. Neither fighting ... with type 1 diabetes. This difference makes sense. Stress blocks the body from releasing insulin in people with type 2 ...

  2. Ganoderma lucidum total triterpenes prevent γ-radiation induced oxidative stress in Swiss albino mice in vivo.

    Science.gov (United States)

    Smina, T P; Joseph, Jini; Janardhanan, K K

    2016-11-01

    The in vivo radio-protective effect of total triterpenes isolated from Ganoderma lucidum (Fr.) P. Karst was evaluated using Swiss albino mice, by pre-treatment with total triterpenes for 14 days, followed by a whole body exposure to γ-radiation. The activities of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx), and the level of reduced glutathione (GSH) were analysed in liver and brain homogenates. The extent of lipid and protein peroxidation was also estimated in liver and brain homogenates after irradiation. Protection of radiation-induced DNA strand breaks in peripheral blood lymphocytes and bone marrow cells was assessed using the comet assay. Total triterpenes were highly effective in reducing the levels of lipid peroxidation and protein oxidation to near normal values in both liver and brain tissues. Total triterpenes, when administered in vivo, were also found to be successful in restoring the antioxidant enzyme activities and GSH level in liver and brain of irradiated mice. Administration of total triterpenes, prior to radiation exposure, significantly decreased the DNA strand breaks. The results of the present study thus revealed the potential therapeutic use of Ganoderma total triterpenes as an adjuvant in radiation therapy.

  3. What on earth is a mainframe ? an introduction to IBM zSeries mainframes and z/OS operating systems for total beginners

    CERN Document Server

    Stephens, David

    2008-01-01

    Looking for a "Mainframes for Beginners" book? Need to learn about z/OS fast? Then this is the book you need. This is the perfect introduction to IBM System z Mainframes and z/OS. Avoiding technical jargon, it gives you the basic facts in clear, light-hearted, entertaining English. You'll quickly learn what Mainframes are, what they do, what runs on them, and terms and terminology you need to speak Mainframe-ese. But it's not all technical. There's also invaluable information about the people that work on Mainframes, Mainframe management issues, new Mainframe trends, and other facts that don't seem to be written down anywhere else. What On Earth is a Mainframe is the closest you'll get to a "Mainframes for Dummies" book. Programmers, managers, recruitment consultants, and industry commentators will all find this book their new best friend when trying to understand the Mainframe world.

  4. Effect of water stress on total biomass, tuber yield, harvest index and water use efficiency in Jerusalem artichoke

    Science.gov (United States)

    The objectives of this study were to determine the effect of drought on tuber yield, total biomass, harvest index, water use efficiency of tuber yield (WUEt) and water use efficiency of biomass (WUEb), and to evaluate the differential responses of Jerusalem artichoke (JA) varieties under drought str...

  5. Wheat cultivars selected for high Fv /Fm under heat stress maintain high photosynthesis, total chlorophyll, stomatal conductance, transpiration and dry matter.

    Science.gov (United States)

    Sharma, Dew Kumari; Andersen, Sven Bode; Ottosen, Carl-Otto; Rosenqvist, Eva

    2015-02-01

    The chlorophyll fluorescence parameter Fv /Fm reflects the maximum quantum efficiency of photosystem II (PSII) photochemistry and has been widely used for early stress detection in plants. Previously, we have used a three-tiered approach of phenotyping by Fv /Fm to identify naturally existing genetic variation for tolerance to severe heat stress (3 days at 40°C in controlled conditions) in wheat (Triticum aestivum L.). Here we investigated the performance of the previously selected cultivars (high and low group based on Fv /Fm value) in terms of growth and photosynthetic traits under moderate heat stress (1 week at 36/30°C day/night temperature in greenhouse) closer to natural heat waves in North-Western Europe. Dry matter accumulation after 7 days of heat stress was positively correlated to Fv /Fm . The high Fv /Fm group maintained significantly higher total chlorophyll and net photosynthetic rate (PN ) than the low group, accompanied by higher stomatal conductance (gs ), transpiration rate (E) and evaporative cooling of the leaf (ΔT). The difference in PN between the groups was not caused by differences in PSII capacity or gs as the variation in Fv /Fm and intracellular CO2 (Ci ) was non-significant under the given heat stress. This study validated that our three-tiered approach of phenotyping by Fv /Fm performed under increasing severity of heat was successful in identifying wheat cultivars differing in photosynthesis under moderate and agronomically more relevant heat stress. The identified cultivars may serve as a valuable resource for further studies to understand the physiological mechanisms underlying the genetic variability in heat sensitivity of photosynthesis. © 2014 Scandinavian Plant Physiology Society.

  6. Acute effect of sorghum flour-containing pasta on plasma total polyphenols, antioxidant capacity and oxidative stress markers in healthy subjects: A randomised controlled trial.

    Science.gov (United States)

    Khan, Imran; Yousif, Adel M; Johnson, Stuart K; Gamlath, Shirani

    2015-06-01

    It has been previously reported that pasta containing wholegrain sorghum flour exhibits high content of polyphenols and antioxidant capacity and hence might enhance antioxidant status and reduce markers of oxidative stress in vivo; however no clinical studies have yet been reported. Therefore, the present study assessed the effect of pasta containing red or white wholegrain sorghum flour on plasma total polyphenols, antioxidant capacity and oxidative stress markers in humans. The study was registered with the Australian New Zealand Clinical Trials Registry (ACTRN: 12612000324819). In a randomised crossover design, healthy subjects (n = 20) consumed three test meals of control pasta (CP), 30% red sorghum pasta (RSP) or 30% white sorghum pasta (WSP), 1-2 wk apart. The test meals were consumed as breakfast after an overnight fast. Blood samples were obtained at fasting and 2 h after consumption and analysed for total polyphenols, antioxidant capacity, superoxide dismutase (SOD) activity, protein carbonyl and 8-isoprostanes. Compared to baseline, the 2 h post-prandial levels following the RSP meal of plasma polyphenols, antioxidant capacity and SOD activity were significantly (P pasta containing red wholegrain sorghum flour enhanced antioxidant status and improved markers of oxidative stress in healthy subjects. Copyright © 2014 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

  7. Inhibition of stress corrosion cracking of alloy AA8090 T-8171 by addition of rare earth salts

    International Nuclear Information System (INIS)

    Davo, B.; Conde, A.; Damborenea, J.J. de

    2005-01-01

    Aluminium-lithium alloys are suitable for aeronautical purposes because of their good mechanical properties and high damage tolerance. Although these alloys are less susceptible to stress corrosion cracking than conventional alloys, Al-Li-Cu-Mg alloy (8090-T8171) still experiences this problem in a NaCl + H 2 O 2 solution. In this work it has been demonstrated that the addition of 10,000 ppm of CeCl 3 to the medium inhibits the stress corrosion cracking of 8090 alloy by precipitation of cerium oxides/hydroxides. The deposition of these compounds on the alloy surface decreases the pit density and slows the crack growth through the grain boundaries by hindering the anodic dissolution of T phases

  8. Influence of alkali metal oxides and alkaline earth metal oxides on the mitigation of stress corrosion cracking in CANDU fuel sheathing

    Energy Technology Data Exchange (ETDEWEB)

    Metzler, J.; Ferrier, G.A.; Farahani, M.; Chan, P.K.; Corcoran, E.C., E-mail: Joseph.Metzler@rmc.ca [Royal Military College of Canada, Kingston, ON (Canada)

    2015-07-01

    This work investigates strategies to mitigate stress corrosion cracking (SCC) in Zircaloy-4 sheathing materials. The CANLUB coatings currently used in CANDU reactors contain both alkali metal and alkaline earth metal impurities, which can exist as oxides (e.g., Na{sub 2}O and CaO). It is believed that when the corrosive fission product iodine reacts with these oxides, the iodine can be sequestered through the formation of an iodide (e.g.,NaI and CaI{sub 2}). The subsequent O{sub 2} release may repair cracks in the protective ZrO{sub 2} layer on the sheathing, shielding the Zircaloy-4 sheathing from further corrosive fission product attack. For this investigation, O{sub 2} gas, Na{sub 2}O, and CaO were separately introduced into an environment wherein slotted Zircaloy-4 rings endure mechanical stresses in iodine vapour at high temperatures. Controlled additions of O{sub 2} gas created a slight reduction in the corrosive attack on Zircaloy-4 sheathing, while the inclusion of Na{sub 2}O and CaO lead to greater reductions. (author)

  9. Near-earth magnetic disturbance in total field at high latitudes. I - Summary of data from Ogo 2, 4, and 6. II - Interpretation of data from Ogo 2, 4, and 6

    Science.gov (United States)

    Langel, R. A.

    1974-01-01

    A complete survey of the near-earth magnetic field magnitude was carried out by the Polar Orbiting Geophysical Observatories (Ogo 2, 4, and 6). The average properties of variations in total magnetic field strength at invariant latitudes greater than 55 deg are given. Data from all degrees of magnetic disturbance are included, the emphasis being on periods when Kp = 2- to 3+. Although individual satellite passes at low altitudes confirm the existence of electrojet currents, neither individual satellite passes nor contours of average delta B are consistent with latitudinally narrow electrojet currents as the principal source of delta B at the satellite. The total field variations at the satellite form a region of positive delta B between about 2200 and 1000 MLT and a region of negative delta B between about 1000 and 2200 MLT. The ratio of delta B magnitudes in these positive and negative regions is variable.

  10. Sports Activity after Low-contact-stress Total Knee Arthroplasty – A long term follow-up study

    Science.gov (United States)

    Vielgut, Ines; Leitner, Lukas; Kastner, Norbert; Radl, Roman; Leithner, Andreas; Sadoghi, Patrick

    2016-01-01

    The purpose of this study was to provide comprehensive long-term data about sports activity levels in patients following total knee arthroplasty (TKA) and to determine the impact of pre-operative function, pain and specific performed sports on the results. 236 patients who have undergone TKA for severe osteoarthritis of the knee were asked to provide specific information regarding exercised types of sports before surgery and after at least 10 years following TKA. Pre- and postoperative function and pain were evaluated by the use of Tegner-, WOMAC- and VAS Score. After a mean of 14.9 years, a significant improvement regarding pain and function was observed. Pre-operative Tegner- and WOMAC scores revealed significant positive correlations with the post-operative Tegner-Score. Accordingly, a high percentage of patients (70.9%) stayed actively involved in sports. Nevertheless, the number of performing patients has decreased according to the sports impact. 71.3% continued practising low-impact-, 43.7% intermediate-impact sports whereas only 16.4% kept performing high impact sports. We conclude that TKA is highly effective in long-time pain reduction as well as improvement of function. Additionally, we found considerable sports activities preserved in the investigated series. However, sports activities in particular, seem to decrease according to the impact of sports. PMID:27090945

  11. Sports Activity after Low-contact-stress Total Knee Arthroplasty - A long term follow-up study.

    Science.gov (United States)

    Vielgut, Ines; Leitner, Lukas; Kastner, Norbert; Radl, Roman; Leithner, Andreas; Sadoghi, Patrick

    2016-04-19

    The purpose of this study was to provide comprehensive long-term data about sports activity levels in patients following total knee arthroplasty (TKA) and to determine the impact of pre-operative function, pain and specific performed sports on the results. 236 patients who have undergone TKA for severe osteoarthritis of the knee were asked to provide specific information regarding exercised types of sports before surgery and after at least 10 years following TKA. Pre- and postoperative function and pain were evaluated by the use of Tegner-, WOMAC- and VAS Score. After a mean of 14.9 years, a significant improvement regarding pain and function was observed. Pre-operative Tegner- and WOMAC scores revealed significant positive correlations with the post-operative Tegner-Score. Accordingly, a high percentage of patients (70.9%) stayed actively involved in sports. Nevertheless, the number of performing patients has decreased according to the sports impact. 71.3% continued practising low-impact-, 43.7% intermediate-impact sports whereas only 16.4% kept performing high impact sports. We conclude that TKA is highly effective in long-time pain reduction as well as improvement of function. Additionally, we found considerable sports activities preserved in the investigated series. However, sports activities in particular, seem to decrease according to the impact of sports.

  12. Estimation of a stress field in the earth`s crust using drilling-induced tensile fractures observed at well WD-1 in the Kakkonda geothermal field; Kakkonda WD-1 sei de kansokusareta drilling induced tensile fracture ni yoru chikaku oryokuba no suitei

    Energy Technology Data Exchange (ETDEWEB)

    Okabe, T. [GERD Geothermal Energy Research and Development Co. Ltd., Tokyo (Japan); Hayashi, K. [Tohoku Univ., Sendai (Japan). Inst. of Fluid Science; Kato, O.; Doi, N.; Miyazaki, S. [Japan Metals and Chemicals Co. Ltd., Tokyo (Japan); Uchida, T. [New Energy and Industrial Technology Development Organization, Tokyo, (Japan)

    1997-05-27

    This paper describes estimation of a stress field in the earth`s crust in the Kakkonda geothermal field. Formation micro imager (FMI) logging known as a crack detecting logging was performed in the well WD-1. This FMI logging has made observation possible on cracks along well axis thought to indicate size and direction of the crust stress, and drilling-induced tensile fractures (DTF). It was verified that these DTFs are generated initially in an azimuth determined by in-situ stress (an angle up to the DTF as measured counterclockwise with due north as a starting point, expressed in {theta}) in the well`s circumferential direction. It was also confirmed that a large number of cracks incline at a certain angle to the well axis (an angle made by the well axis and the DTF, expressed in {gamma}). The DTF is a crack initially generated on well walls as a result of such tensile stresses as mud pressure and thermal stress acting on the well walls during well excavation, caused by the in-situ stress field. Measurement was made on the {theta} and {gamma} from the FMI logging result, and estimation was given on a three-dimensional stress field. Elucidating the three-dimensional crust stress field in a geothermal reservoir is important in making clear the formation mechanism thereof and the growth of water-permeable cracks. This method can be regarded as an effective method. 9 refs., 8 figs., 1 tab.

  13. Stress

    DEFF Research Database (Denmark)

    Keller, Hanne Dauer

    2015-01-01

    Kapitlet handler om stress som følelse, og det trækker primært på de få kvalitative undersøgelser, der er lavet af stressforløb.......Kapitlet handler om stress som følelse, og det trækker primært på de få kvalitative undersøgelser, der er lavet af stressforløb....

  14. Stress !!!

    OpenAIRE

    Fledderus, M.

    2012-01-01

    Twee op de vijf UT-studenten hebben last van ernstige studiestress, zo erg zelfs dat het ze in hun privéleven belemmert. Die cijfers komen overeen met het landelijk beeld van stress onder studenten. Samen met 14 andere universiteits- en hogeschoolbladen enquêteerde UT Nieuws bijna 5500 studenten. Opvallend is dat mannelijke studenten uit Twente zich veel minder druk lijken te maken over hun studie. Onder vrouwen ligt de stress juist erg hoog ten opzichte van het landelijk gemiddelde.

  15. Melatonin prevents inflammation and oxidative stress caused by abdominopelvic and total body irradiation of rat small intestine.

    Science.gov (United States)

    Guney, Y; Hicsonmez, A; Uluoglu, C; Guney, H Z; Ozel Turkcu, U; Take, G; Yucel, B; Caglar, G; Bilgihan, A; Erdogan, D; Nalca Andrieu, M; Kurtman, C; Zengil, H

    2007-10-01

    We investigated the day-night differences in intestinal oxidative-injury and the inflammatory response following total body (TB) or abdominopelvic (AP) irradiation, and the influence of melatonin administration on tissue injury induced by radiation. Rats (male Wistar, weighing 220-280 g) in the irradiated groups were exposed to a dose of 8 Gy to the TB or AP region in the morning (resting period - 1 h after light onset) or evening (activity span - 13 h after light onset). Vehicle or melatonin was administered immediately before, immediately after and 24 h after irradiation (10, 2.0 and 10 mg/kg, ip, respectively) to the irradiated rats. AP (P < 0.05) and TB (P < 0.05) irradiation applied in the morning caused a significant increase in thiobarbituric acid reactive substance (TBARS) levels. Melatonin treatment in the morning (P < 0.05) or evening (P < 0.05) decreased TBARS levels after TB irradiation. After AP irradiation, melatonin treatment only in the morning caused a significant decrease in TBARS levels (P < 0.05). Although we have confirmed the development of inflammation after radiotherapy by histological findings, neither AP nor TB irradiation caused any marked changes in myeloperoxidase activity in the morning or evening. Our results indicate that oxidative damage is more prominent in rats receiving TB and AP irradiation in the morning and melatonin appears to have beneficial effects on oxidative damage irrespective of the time of administration. Increased neutrophil accumulation indicates that melatonin administration exerts a protective effect on AP irradiation-induced tissue oxidative injury, especially in the morning.

  16. Melatonin prevents inflammation and oxidative stress caused by abdominopelvic and total body irradiation of rat small intestine

    Directory of Open Access Journals (Sweden)

    Y. Guney

    2007-10-01

    Full Text Available We investigated the day-night differences in intestinal oxidative-injury and the inflammatory response following total body (TB or abdominopelvic (AP irradiation, and the influence of melatonin administration on tissue injury induced by radiation. Rats (male Wistar, weighing 220-280 g in the irradiated groups were exposed to a dose of 8 Gy to the TB or AP region in the morning (resting period - 1 h after light onset or evening (activity span - 13 h after light onset. Vehicle or melatonin was administered immediately before, immediately after and 24 h after irradiation (10, 2.0 and 10 mg/kg, ip, respectively to the irradiated rats. AP (P < 0.05 and TB (P < 0.05 irradiation applied in the morning caused a significant increase in thiobarbituric acid reactive substance (TBARS levels. Melatonin treatment in the morning (P < 0.05 or evening (P < 0.05 decreased TBARS levels after TB irradiation. After AP irradiation, melatonin treatment only in the morning caused a significant decrease in TBARS levels (P < 0.05. Although we have confirmed the development of inflammation after radiotherapy by histological findings, neither AP nor TB irradiation caused any marked changes in myeloperoxidase activity in the morning or evening. Our results indicate that oxidative damage is more prominent in rats receiving TB and AP irradiation in the morning and melatonin appears to have beneficial effects on oxidative damage irrespective of the time of administration. Increased neutrophil accumulation indicates that melatonin administration exerts a protective effect on AP irradiation-induced tissue oxidative injury, especially in the morning.

  17. Formation of a vitreous phase at the surface of some commercial diatomaceous earth prevents the onset of oxidative stress effects.

    Science.gov (United States)

    Ghiazza, Mara; Gazzano, Elena; Bonelli, Barbara; Fenoglio, Ivana; Polimeni, Manuela; Ghigo, Dario; Garrone, Edoardo; Fubini, Bice

    2009-01-01

    To understand the effect of the commercial processing of diatomaceous earths (DEs) on their ultimate surface structure and potential toxicity, we investigated the influence of the industrial processing and the nature of the deposit. Two flux calcined specimens from different deposits, DE/1-FC and DE/2-FC, and the simply calcined sample DE/1-C, from the same deposit as DE/1-FC, were compared in both their bulk and their surface properties. X-ray diffraction (XRD) analysis in a heating chamber revealed the presence of cristobalite in all samples, more abundant on the flux calcined ones. The crystal lattice is probably imperfect, as the alpha-beta transition, visible by XRD in DE/1-FC and DE/2-FC, is not detected by differential scanning calorimetry. Progressive etching with HF solutions suggests that most of the crystalline phase is at the core and not at the outer region of the samples. The combined use of spectroscopic (UV-vis and IR) and calorimetric techniques (heat of adsorption of water as a measure of hydrophilicity) reveals that DE/1-FC and DE/2-FC particles have an external layer of glass, absent in DE/1-C, where iron impurities act as network-forming and sodium ions as modifier species, with few patches of a hydrophobic phase, the latter relatable to a heated pure silica phase. When tested on a macrophage cell line (MH-S) in comparison with appropriate positive and negative controls (an active and an inactive quartz dust, respectively), only DE/1-C exhibited a cell damage and activation similar to that of active quartz (measured by lactate dehydrogenase release, peroxidation of membrane lipids and synthesis of NO). It is likely that the presence of a vitreous phase mitigates or even eliminates the cellular responses of silica in DE.

  18. Stress !!!

    NARCIS (Netherlands)

    Fledderus, M.

    2012-01-01

    Twee op de vijf UT-studenten hebben last van ernstige studiestress, zo erg zelfs dat het ze in hun privéleven belemmert. Die cijfers komen overeen met het landelijk beeld van stress onder studenten. Samen met 14 andere universiteits- en hogeschoolbladen enquêteerde UT Nieuws bijna 5500 studenten.

  19. The contribution of total and free iodothyronines to welfare maintenance and management stress coping in Ruminants and Equines: Physiological ranges and reference values.

    Science.gov (United States)

    Ferlazzo, Adriana; Cravana, Cristina; Fazio, Esterina; Medica, Pietro

    2018-06-01

    In order to acquire a pattern of thyroid involvement in welfare maintenance in Ruminants and Equines, this review summarizes data concerning the reference values of total and free iodothyronines and their modifications in physiological conditions and in different management conditions (pregnancy, lactation, weaning, growth, isolation, restraint, shearing, confinement and transportation). Thyroidal and extrathyroidal tissues efficiently respond to management practices, giving a differentiated contribution to circulating iodothyronine changes. The hormonal response could be mainly attributed to the intracellular deiodination of T 4 to T 3. Triiodothyronine (T 3 ) and free iodothyronines (fT 3 and fT 4 ) result more responsive to management stress, showing different pattern with species and to various conditions, as to environmental conditions in which activities are performed. Intrinsic seasonal changes of iodothyronines and a significant pregnancy effect for T 3 were recorded in mares. Higher, although not significant, T 3 and T 4 concentrations in barren than pregnant mares were observed in donkeys. A positive significant correlation between T 3 and T 4 was described only in pregnant donkeys. Moreover, a significant effect of season on T 3 and fT 3 changes was observed both in pregnant and barren donkeys. A significant lactating effect compared with nonlactating stage for T 3 and T 4 was recorded in mares. In growing foals, body weight (BW) and age were positively correlated with T 3 and negatively correlated with T 4 , fT 4 and fT 3 . Weaning effects were shown for T 3 and fT 4 concentrations, indicating that weaning represents a severe stress and the presence of conspecific does not reduce psychological stress in this phase. Lambs showed significant decreased T 3 and elevated T 4 concentrations two weeks after weaning, with higher concentrations in both males and females compared to 24 h. Significant positive correlations were observed between BW and T 4 , fT 3

  20. Stress.

    Science.gov (United States)

    Chambers, David W

    2008-01-01

    We all experience stress as a regular, and sometimes damaging and sometimes useful, part of our daily lives. In our normal ups and downs, we have our share of exhaustion, despondency, and outrage--matched with their corresponding positive moods. But burnout and workaholism are different. They are chronic, dysfunctional, self-reinforcing, life-shortening habits. Dentists, nurses, teachers, ministers, social workers, and entertainers are especially susceptible to burnout; not because they are hard-working professionals (they tend to be), but because they are caring perfectionists who share control for the success of what they do with others and perform under the scrutiny of their colleagues (they tend to). Workaholics are also trapped in self-sealing cycles, but the elements are ever-receding visions of control and using constant activity as a barrier against facing reality. This essay explores the symptoms, mechanisms, causes, and successful coping strategies for burnout and workaholism. It also takes a look at the general stress response on the physiological level and at some of the damage American society inflicts on itself.

  1. Total Flavonoids from Rosa laevigata Michx Fruit Ameliorates Hepatic Ischemia/Reperfusion Injury through Inhibition of Oxidative Stress and Inflammation in Rats

    Directory of Open Access Journals (Sweden)

    Xufeng Tao

    2016-07-01

    Full Text Available The effects of total flavonoids (TFs from Rosa laevigata Michx fruit against liver damage and cerebral ischemia/reperfusion (I/R injury have been reported, but its action on hepatic I/R injury remains unknown. In this work, the effects and possible mechanisms of TFs against hepatic I/R injury were examined using a 70% partial hepatic warm ischemia rat model. The results demonstrated TFs decreased serum aspartate transaminase (AST, alanine aminotransferase (ALT, myeloperoxidase (MPO, and lactate dehydrogenase (LDH activities, improved liver histopathology and ultrastructure through hematoxylin-eosin (HE staining and electron microscope observation. In addition, TFs significantly decreased malondialdehyde (MDA and increased the levels of superoxide dismutase (SOD and glutathione peroxidase (GSH-Px, which indicated that TFs alleviated oxidative stress caused by I/R injury. RT-PCR results proved that TFs downregulated the gene levels of inflammatory factors including interleukin-1 beta (IL-1β, interleukin-1 (IL-6, and tumor necrosis factor alpha (TNF-α. Further research indicated that TF-induced hepatoprotection was completed through inhibiting TLR4/MyD88 and activating Sirt1/Nrf2 signaling pathways. Blockade of the TLR4 pathway by TFs inhibited NF-κB and AP-1 transcriptional activities and inflammatory reaction. Activation of Sirt1/Nrf2 pathway by TFs increased the protein levels of HO-1 and GST to improve oxidative stress. Collectively, these findingsconfirmed the potent effects of TFs against hepatic I/R injury, which should be developed as a candidate for the prevention of this disease.

  2. Prophylactic Neuroprotection of Total Glucosides of Paeoniae Radix Alba against Semen Strychni-Induced Neurotoxicity in Rats: Suppressing Oxidative Stress and Reducing the Absorption of Toxic Components.

    Science.gov (United States)

    Li, Shujuan; Chu, Yanjie; Zhang, Ruowen; Sun, Linjia; Chen, Xiaohui

    2018-04-20

    Strychnos alkaloids (SAs) are the main toxic constituents in Semen Strychni, a traditional Chinese medicine, which is known for its fatal neurotoxicity. Hence, the present study was carried out to evaluate the neurotoxicity induced by SAs and the pre-protective effects of the total glucosides of Paeoniae Radix Alba (TGP). An SA brain damage model was firstly established. The neurotoxicity induced by SAs and the pre-protective effects of TGP were confirmed by physical and behavioral testing, biochemical assay, and histological examination. Then, a liquid chromatography-tandem mass spectrometry method was developed and validated to investigate the time-course change and distribution of strychnine and brucine (two main SAs) in the brain after oral SA administration with or without TGP pretreatment. Biochemical analysis results indicated that TGP could ameliorate the oxidative stress status caused by SAs. Time-course change and distribution studies demonstrated that strychnine and brucine were rapidly absorbed into the brain, peaked early at 0.5 h, and were mainly located in the hippocampus and cerebellum. TGP showed a pre-protective effect against neurotoxicity by reducing the absorption of toxic alkaloids into the brain. These findings could provide beneficial information in facilitating future studies of Semen Strychni neurotoxicity and developing herbal medicines to alleviate neurotoxicity in the clinic.

  3. Prophylactic Neuroprotection of Total Glucosides of Paeoniae Radix Alba against Semen Strychni-Induced Neurotoxicity in Rats: Suppressing Oxidative Stress and Reducing the Absorption of Toxic Components

    Directory of Open Access Journals (Sweden)

    Shujuan Li

    2018-04-01

    Full Text Available Strychnos alkaloids (SAs are the main toxic constituents in Semen Strychni, a traditional Chinese medicine, which is known for its fatal neurotoxicity. Hence, the present study was carried out to evaluate the neurotoxicity induced by SAs and the pre-protective effects of the total glucosides of Paeoniae Radix Alba (TGP. An SA brain damage model was firstly established. The neurotoxicity induced by SAs and the pre-protective effects of TGP were confirmed by physical and behavioral testing, biochemical assay, and histological examination. Then, a liquid chromatography-tandem mass spectrometry method was developed and validated to investigate the time-course change and distribution of strychnine and brucine (two main SAs in the brain after oral SA administration with or without TGP pretreatment. Biochemical analysis results indicated that TGP could ameliorate the oxidative stress status caused by SAs. Time-course change and distribution studies demonstrated that strychnine and brucine were rapidly absorbed into the brain, peaked early at 0.5 h, and were mainly located in the hippocampus and cerebellum. TGP showed a pre-protective effect against neurotoxicity by reducing the absorption of toxic alkaloids into the brain. These findings could provide beneficial information in facilitating future studies of Semen Strychni neurotoxicity and developing herbal medicines to alleviate neurotoxicity in the clinic.

  4. N-Acetylcysteine Supplementation Controls Total Antioxidant Capacity, Creatine Kinase, Lactate, and Tumor Necrotic Factor-Alpha against Oxidative Stress Induced by Graded Exercise in Sedentary Men

    Directory of Open Access Journals (Sweden)

    Donrawee Leelarungrayub

    2011-01-01

    Full Text Available Aim of this study was to evaluate the effects of short-term (7 days N-acetylcysteine (NAC at 1,200 mg daily supplementation on muscle fatigue, maximal oxygen uptake (VO2max, total antioxidant capacity (TAC, lactate, creatine kinase (CK, and tumor necrotic factor-alpha (TNF-α. Twenty-nine sedentary men (13 controls; 16 in the supplement group from a randomized control were included. At before and after supplementation, fatigue index (FI was evaluated in the quadriceps muscle, and performed a graded exercise treadmill test to induce oxidative stress, and as a measure of VO2max. Blood samples were taken before exercise and 20 minutes after it at before and after supplementation, to determine TAC, CK, lactate, and TNF-α levels. Results showed that FI and VO2max increased significantly in the supplement group. After exercise decreased the levels of TAC and increased lactate, CK, and TNF-α of both groups at before supplementation. After supplementation, lactate, CK, and TNF-α levels significantly increased and TAC decreased after exercise in the control group. Whereas the TAC and lactate levels did not change significantly, but CK and TNF-α increased significantly in the supplement group. Therefore, this results showed that NAC improved the muscle fatigue, VO2max, maintained TAC, controlled lactate production, but had no influence on CK and TNF-α.

  5. Sulfur Earth

    Science.gov (United States)

    de Jong, B. H.

    2007-12-01

    Variations in surface tension affect the buoyancy of objects floating in a liquid. Thus an object floating in water will sink deeper in the presence of dishwater fluid. This is a very minor but measurable effect. It causes for instance ducks to drown in aqueous solutions with added surfactant. The surface tension of liquid iron is very strongly affected by the presence of sulfur which acts as a surfactant in this system varying between 1.9 and 0.4 N/m at 10 mass percent Sulfur (Lee & Morita (2002), This last value is inferred to be the maximum value for Sulfur inferred to be present in the liquid outer core. Venting of Sulfur from the liquid core manifests itself on the Earth surface by the 105 to 106 ton of sulfur vented into the atmosphere annually (Wedepohl, 1984). Inspection of surface Sulfur emission indicates that venting is non-homogeneously distributed over the Earth's surface. The implication of such large variation in surface tension in the liquid outer core are that at locally low Sulfur concentration, the liquid outer core does not wet the predominantly MgSiO3 matrix with which it is in contact. However at a local high in Sulfur, the liquid outer core wets this matrix which in the fluid state has a surface tension of 0.4 N/m (Bansal & Doremus, 1986), couples with it, and causes it to sink. This differential and diapiric movement is transmitted through the essentially brittle mantle (1024 Pa.s, Lambeck & Johnson, 1998; the maximum value for ice being about 1030 Pa.s at 0 K, in all likely hood representing an upper bound of viscosity for all materials) and manifests itself on the surface by the roughly 20 km differentiation, about 0.1 % of the total mantle thickness, between topographical heights and lows with concomitant lateral movement in the crust and upper mantle resulting in thin skin tectonics. The brittle nature of the medium though which this movement is transmitted suggests that the extremes in topography of the D" layer are similar in range to

  6. Shredded beet pulp substituted for corn silage in diets fed to dairy cows under ambient heat stress: Feed intake, total-tract digestibility, plasma metabolites, and milk production.

    Science.gov (United States)

    Naderi, N; Ghorbani, G R; Sadeghi-Sefidmazgi, A; Nasrollahi, S M; Beauchemin, K A

    2016-11-01

    ammonia-nitrogen and milk concentration of urea, corresponding to an increase in percentage of protein in milk. Compared with multiparous cows, primiparous cows had greater rumen pH, metabolite concentrations in plasma (glucose, cholesterol, urea nitrogen, total protein, and globulins), milk production, and concentrations of milk components. Substituting beet pulp for corn silage at up to 12% of dietary dry matter can be beneficial during heat stress conditions. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  7. Rare earths

    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.

  8. Updated of the events tree of total loss of power at the site, SBO, taking into account the results of stress tests and methodological updates, convolution, and hydraulic power recovery from model RCPs

    International Nuclear Information System (INIS)

    Lopez Lorenzo, M. A.; Perez Martin, F.

    2013-01-01

    In this paper, is described a tree of events to an accident loss total power at the site (SBO) considering, first the results of stress tests arising from the Fukushima accident and moreover, various methodological updates related to this initiating event.

  9. Total protein

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/003483.htm Total protein To use the sharing features on this page, please enable JavaScript. The total protein test measures the total amount of two classes ...

  10. In the Red Shadow of the Earth

    Science.gov (United States)

    Hughes, Stephen W.; Hosokawa, Kazuyuki; Carroll, Joshua; Sawell, David; Wilson, Colin

    2015-01-01

    A technique is described for calculating the brightness of the atmosphere of the Earth that shines into the Earth's umbra during a total lunar eclipse making the Moon red. This "Rim of Fire" is due to refracted unscattered light from all the sunrises and sunsets rimming the Earth. In this article, a photograph of the totally eclipsed…

  11. Rare earths

    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.)

  12. Impact of different analgesic depths and abdominal trauma of different severities on stress and recovery of rats undergoing total intravenous anesthesia

    Directory of Open Access Journals (Sweden)

    Huang HM

    2017-05-01

    Full Text Available Hai-ming Huang,1,2 Jun Cao,3 Lin-mei Zhu,4 Yu-qing Chen,2 Fu-ding Lu,2 Hong-wei Cai1 1Department of Anesthesiology, Xiangya Hospital, Central South University, Changsha, 2Department of Anesthesiology, 3Department of Hepatic and Biliary Pancreatic Surgery, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, 4Department of Obstetrics and Gynecology, Clifford Hospital, Guangzhou University of Chinese Medicine, Guangzhou, People’s Republic of China Abstract: A number of animal models have been developed to examine the pathophysiological consequences of surgical procedures, but anesthetic methods, monitoring, and management measures in these models are very different from those used in humans. This study was designed to create a rat model of abdominal surgery using anesthetic methods and perioperative treatment similar to those used in the clinic and to investigate the effects of different injury severities and depths of anesthesia and analgesia on surgical stress and postoperative recovery. Abdominal skin/muscle incision was compared with exploratory laparotomy in rats under propofol intravenous anesthesia, accompanied by perioperative measures such as oxygen inhalation, fluid infusion, warmth, blood gas analysis, and infection prevention. Stress indices (mean arterial pressure, heart rate, blood glucose, and plasma corticosterone were monitored during anesthesia and surgery, and recovery indicators (body weight, food consumption, and pain were measured after surgery. In addition, animals undergoing laparotomy were subjected to low and high dosages of propofol and sufentanil, in order to examine the relationship between anesthetic and analgesic depth and stress on recovery. Exploratory laparotomy induced a greater stress response and caused slower postoperative recovery as measured than somatic injury. High-dose sufentanil downregulated plasma corticosterone and improved postoperative recovery more effectively than high-dose propofol (P<0

  13. Total algorithms

    NARCIS (Netherlands)

    Tel, G.

    We define the notion of total algorithms for networks of processes. A total algorithm enforces that a "decision" is taken by a subset of the processes, and that participation of all processes is required to reach this decision. Total algorithms are an important building block in the design of

  14. 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...

  15. Work-Home Interference, Perceived Total Workload, and the Risk of Future Sickness Absence Due to Stress-Related Mental Diagnoses Among Women and Men: a Prospective Twin Study.

    Science.gov (United States)

    Svedberg, Pia; Mather, Lisa; Bergström, Gunnar; Lindfors, Petra; Blom, Victoria

    2018-02-01

    Work-home interference has been proposed as an important explanation for sickness absence (SA). Previous studies show mixed results, have not accounted for familial factors (genetics and shared everyday environment), or investigated diagnosis specific SA. The aim was to study whether work-home interference and perceived total workload predict SA due to stress-related mental diagnoses, or SA due to other mental diagnoses, among women and men, when adjusting for various confounders and familial factors. This study included 11,916 twins, 19-47 years (49% women). Data on work-to-home and home-to-work conflicts, perceived total workload, and relevant confounders were derived from a 2005 survey, and national register data on SA spells until 2013 were obtained. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated. Discordant twin pair design was applied to adjust for familial factors. Each one unit increase in work-to-home and home-to-work conflicts, and perceived total workload was associated with higher odds for SA due to stress-related mental diagnoses and to SA due to other mental diagnoses among women, when adjusting for sociodemographic factors (ORs 1.15-1.31). Including health or familial factors, no associations remained. For men, each one unit increase in work-to-home conflicts was associated with higher odds for SA due to stress-related diagnoses (ORs 1.23-1.35), independently of confounders. Work-to-home conflict was independently associated with future SA due to stress-related diagnoses among men only. Health- and work-related factors seem to be important confounders when researching work-home interference, perceived total workload, and SA. Not including such confounders involves risking drawing incorrect conclusions. Further studies are needed to confirm sex differences and whether genetic factors are important for the associations studied.

  16. Differences in the stress distribution in the distal femur between patellofemoral joint replacement and total knee replacement: a finite element study

    NARCIS (Netherlands)

    van Jonbergen, H.P.; Innocenti, B.; Gervasi, G.L.; Labey, L.; Verdonschot, N.J.

    2012-01-01

    BACKGROUND: Patellofemoral joint replacement is a successful treatment option for isolated patellofemoral osteoarthritis. However, results of later conversion to total knee replacement may be compromised by periprosthetic bone loss. Previous clinical studies have demonstrated a decrease in distal

  17. Digital Earth - A sustainable Earth

    Science.gov (United States)

    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.

  18. Totally James

    Science.gov (United States)

    Owens, Tom

    2006-01-01

    This article presents an interview with James Howe, author of "The Misfits" and "Totally Joe". In this interview, Howe discusses tolerance, diversity and the parallels between his own life and his literature. Howe's four books in addition to "The Misfits" and "Totally Joe" and his list of recommended books with lesbian, gay, bisexual, transgender,…

  19. Fratura periprotética da tíbia combinada com fratura de fadiga da haste tibial de artroplastia total do joelho Tibial periprosthetic fracture combined with tibial stem stress fracture from total knee arthroplasty

    Directory of Open Access Journals (Sweden)

    Fernando Fonseca

    2011-01-01

    Full Text Available As complicações das artroplastias totais do joelho relacionadas com o próprio material são muito raras, exceto o desgaste do polietileno. Neste artigo os autores reportam o caso de uma paciente do sexo feminino de 58 anos referenciada ao pronto-socorro do nosso hospital por uma fratura periprotética tibial (tipo I da classificação da Mayo Clinic. Uma observação mais cuidadosa mostrou a presença concomitante da referida fratura da tíbia associada à fratura de fadiga da haste tibial. A prótese com a haste foi remetida a um laboratório de biomecânica independente onde foi avaliada e efetuada uma reconstrução com uso de sistema de elementos finitos em CAD de modo a verificar a existência de algum defeito de fabricação e as eventuais causas para o sucedido. Depois de avaliadas diversas hipóteses, concluiu-se que a fratura do material foi provocada por uma sobrecarga na zona de transição prato/haste secundária à falência óssea prévia (fratura. Da avaliação do caso ressalta-se novamente a necessidade de efetuar uma avaliação adequada da mineralização óssea e, em caso de dúvida, utilizar uma haste longa.Total knee arthroplasty complications related to the prosthetic material are very rare, except for polyethylene wear. We report the case of a 58-year-old woman who came to the emergency service of our hospital with a periprosthetic tibial fracture (Mayo Clinic type I. Careful examination showed that this fracture was concomitantly associated with a tibial stem fatigue fracture. The prosthesis and the stem were sent to an independent biomechanics laboratory for evaluation. A finite-element CAD system was used to make a reconstruction, so as to ascertain whether there had been any manufacturing defect and what the causes of the event might have been. After evaluation of several hypotheses, it was concluded that the fracture in the prosthetic material had been caused by overloading at the plate/stem transition zone

  20. The earth's hydrological cycle

    CERN Document Server

    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 ...

  1. Total Water Management - Report

    Science.gov (United States)

    There is a growing need for urban water managers to take a more holistic view of their water resource systems as population growth, urbanization, and current operations put different stresses on the environment and urban infrastructure. Total Water Management (TWM) is an approac...

  2. Effects of oral Ginkgo biloba supplementation on cataract formation and oxidative stress occurring in lenses of rats exposed to total cranium radiotherapy

    International Nuclear Information System (INIS)

    Ertekin, M.V.; Kocer, I.; Karslioglu, I.; Taysi, S.; Gepdiremen, A.; Sezen, O.; Balci, E.; Bakan, N.

    2004-01-01

    The objective of this study was to determine the antioxidant role of Ginkgo biloba (GB) in preventing radiation-induced cataracts in the lens after total-cranium irradiation of rats with a single radiation dose of 5 Gy. Sprague-Dawley rats were randomly divided into three groups. Group 1 received neither GB nor irradiation (control group). Group 2 was exposed to total-cranium irradiation of 5 Gy in a single dose [radiation therapy (RT) group], and group 3 received total cranium irradiation from a cobalt-60 teletherapy unit, plus 40 mg/kg per day GB (RT+GB group). At the end of the tenth day, the rats were killed and their eyes were enucleated to measure the antioxidant enzymes, the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and the lipid peroxidation level [malondialdehyde (MDA)]. Irradiation significantly increased both the MDA level and the activity of GSH-Px, and significantly decreased the activity of SOD in the rat lenses. GB supplementation significantly increased the activities of SOD and GSH-Px enzymes and significantly decreased the MDA level. Total cranium irradiation of 5 Gy in a single dose promoted cataract formation, and GB supplementation protected the lenses from radiation-induced cataracts. We suggest that Grinkgo biloba is an antioxidant that protects the rat lens from radiation-induced cataracts. (author)

  3. Allometric relations of total volumes of prolactin cells and corticotropic cells to body length in the annual cyprinodont Cynolebias whitei: effects of environmental salinity, stress and ageing

    NARCIS (Netherlands)

    Ruijter, J. M.; Wendelaar Bonga, S. E.

    1987-01-01

    An analysis of the allometric relations of the total volumes occupied by prolactin (PRL) and corticotropic (ACTH) cells (PRL volume and ACTH volume, respectively) to body length and a study of the immunocytochemical staining intensity of PRL and ACTH cells were used to determine the differences in

  4. Earth thermics

    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.

  5. Earth Pressure on Tunnel Crown

    DEFF Research Database (Denmark)

    Andersen, Lars

    Two different analyses have been carried out in order to find the vertical earth pressure, or overburden pressure, at the crown of a tunnel going through a dike. Firstly, a hand calculation is performed using a simple dispersion of the stresses over depth. Secondly, the finite‐element program...

  6. Total meltwater volume since the Last Glacial Maximum and viscosity structure of Earth's mantle inferred from relative sea level changes at Barbados and Bonaparte Gulf and GIA-induced J˙2

    Science.gov (United States)

    Nakada, Masao; Okuno, Jun'ichi; Yokoyama, Yusuke

    2016-02-01

    Inference of globally averaged eustatic sea level (ESL) rise since the Last Glacial Maximum (LGM) highly depends on the interpretation of relative sea level (RSL) observations at Barbados and Bonaparte Gulf, Australia, which are sensitive to the viscosity structure of Earth's mantle. Here we examine the RSL changes at the LGM for Barbados and Bonaparte Gulf ({{RSL}}_{{L}}^{{{Bar}}} and {{RSL}}_{{L}}^{{{Bon}}}), differential RSL for both sites (Δ {{RSL}}_{{L}}^{{{Bar}},{{Bon}}}) and rate of change of degree-two harmonics of Earth's geopotential due to glacial isostatic adjustment (GIA) process (GIA-induced J˙2) to infer the ESL component and viscosity structure of Earth's mantle. Differential RSL, Δ {{RSL}}_{{L}}^{{{Bar}},{{Bon}}} and GIA-induced J˙2 are dominantly sensitive to the lower-mantle viscosity, and nearly insensitive to the upper-mantle rheological structure and GIA ice models with an ESL component of about (120-130) m. The comparison between the predicted and observationally derived Δ {{RSL}}_{{L}}^{{{Bar}},{{Bon}}} indicates the lower-mantle viscosity higher than ˜2 × 1022 Pa s, and the observationally derived GIA-induced J˙2 of -(6.0-6.5) × 10-11 yr-1 indicates two permissible solutions for the lower mantle, ˜1022 and (5-10) × 1022 Pa s. That is, the effective lower-mantle viscosity inferred from these two observational constraints is (5-10) × 1022 Pa s. The LGM RSL changes at both sites, {{RSL}}_{{L}}^{{{Bar}}} and {{RSL}}_{{L}}^{{{Bon}}}, are also sensitive to the ESL component and upper-mantle viscosity as well as the lower-mantle viscosity. The permissible upper-mantle viscosity increases with decreasing ESL component due to the sensitivity of the LGM sea level at Bonaparte Gulf ({{RSL}}_{{L}}^{{{Bon}}}) to the upper-mantle viscosity, and inferred upper-mantle viscosity for adopted lithospheric thicknesses of 65 and 100 km is (1-3) × 1020 Pa s for ESL˜130 m and (4-10) × 1020 Pa s for ESL˜125 m. The former solution of (1-3) × 1020

  7. WAVE TECTONICS OF THE EARTH

    Directory of Open Access Journals (Sweden)

    Tatiana Yu. Tveretinova

    2010-01-01

    Full Text Available In the Earth's lithosphere, wavy alternation of positive and negative heterochronous structures is revealed; such structures are variable in ranks and separated by vergence zones of fractures and folds. In the vertical profile of the lithosphere, alternating are layers characterized by relatively plastic or fragile rheological properties and distinguished by different states of stress. During the Earth’s evolution, epochs of compression and extension are cyclically repeated, including planetary-scale phenomena which are manifested by fluctuating changes of the planet’s volume. Migration of geological and geophysical (geodynamic processes takes place at the Earth's surface and in its interior. The concept of the wave structure and evolution of the Earth's lithosphere provides explanations to the abovementioned regularities. Wavy nature of tectonic structures of the lithosphere, the cyclic recurrence of migration and geological processes in space and time can be described in terms of the multiple-order wave geodynamics of the Earth's lithosphere that refers to periodical variations of the state of stress. Effects of structure-forming tectonic forces are determined by «interference» of tangential and radial stresses of the Earth. The tangential stresses, which occur primarily due to the rotational regime of the planet, cause transformations of the Earth’s shape, redistributions of its substance in depths, the westward drift of the rock mass in its upper levels, and changes of structural deformation plans. The radial stresses, which are largely impacted by gravity, determine the gravitational differentiation of the substance, vertical flattening and sub-horizontal flow of the rock masses, and associated fold-rupture deformation. Under the uniform momentum geodynamic concept proposed by [Vikulin, Tveritinova, 2004, 2005, 2007, 2008], it is possible to provide consistent descriptions of seismic and volcanic, tectonic and geological processes

  8. Earth current monitoring circuit for inductive loads

    CERN Document Server

    Montabonnet, V; Thurel, Y; Cussac, P

    2010-01-01

    The search for higher magnetic fields in particle accelerators increasingly demands the use of superconducting magnets. This magnet technology has a large amount of magnetic energy storage during operation at relatively high currents. As such, many monitoring and protection systems are required to safely operate the magnet, including the monitoring of any leakage of current to earth in the superconducting magnet that indicates a failure of the insulation to earth. At low amplitude, the earth leakage current affects the magnetic field precision. At a higher level, the earth leakage current can additionally generate local losses which may definitively damage the magnet or its instrumentation. This paper presents an active earth fault current monitoring circuit, widely deployed in the converters for the CERN Large Hadron Collider (LHC) superconducting magnets. The circuit allows the detection of earth faults before energising the circuit as well as limiting any eventual earth fault current. The electrical stress...

  9. Rare earth elements: end use and recyclability

    Science.gov (United States)

    Goonan, Thomas G.

    2011-01-01

    Rare earth elements are used in mature markets (such as catalysts, glassmaking, lighting, and metallurgy), which account for 59 percent of the total worldwide consumption of rare earth elements, and in newer, high-growth markets (such as battery alloys, ceramics, and permanent magnets), which account for 41 percent of the total worldwide consumption of rare earth elements. In mature market segments, lanthanum and cerium constitute about 80 percent of rare earth elements used, and in new market segments, dysprosium, neodymium, and praseodymium account for about 85 percent of rare earth elements used. Regardless of the end use, rare earth elements are not recycled in large quantities, but could be if recycling became mandated or very high prices of rare earth elements made recycling feasible.

  10. Total Thyroidectomy

    Directory of Open Access Journals (Sweden)

    Lopez Moris E

    2016-06-01

    Full Text Available Total thyroidectomy is a surgery that removes all the thyroid tissue from the patient. The suspect of cancer in a thyroid nodule is the most frequent indication and it is presume when previous fine needle puncture is positive or a goiter has significant volume increase or symptomes. Less frequent indications are hyperthyroidism when it is refractory to treatment with Iodine 131 or it is contraindicated, and in cases of symptomatic thyroiditis. The thyroid gland has an important anatomic relation whith the inferior laryngeal nerve and the parathyroid glands, for this reason it is imperative to perform extremely meticulous dissection to recognize each one of these elements and ensure their preservation. It is also essential to maintain strict hemostasis, in order to avoid any postoperative bleeding that could lead to a suffocating neck hematoma, feared complication that represents a surgical emergency and endangers the patient’s life.It is essential to run a formal technique, without skipping steps, and maintain prudence and patience that should rule any surgical act.

  11. Rotation of a Moonless Earth

    Science.gov (United States)

    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.

  12. Earth Science Enterprise Technology Strategy

    Science.gov (United States)

    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.

  13. Updated of the events tree of total loss of power at the site, SBO, taking into account the results of stress tests and methodological updates, convolution, and hydraulic power recovery from model RCPs; Actualizacion del arbol de sucesos de perdida total de suministro electro en el emplazamiento, SBO, teniendo en cuenta los resultados de los estres tests y actualizaciones metodologicas, convolucion, recuperacion desde centrales hidraulicas y modelo de sellos de las RCPs

    Energy Technology Data Exchange (ETDEWEB)

    Lopez Lorenzo, M. A.; Perez Martin, F.

    2013-07-01

    In this paper, is described a tree of events to an accident loss total power at the site (SBO) considering, first the results of stress tests arising from the Fukushima accident and moreover, various methodological updates related to this initiating event.

  14. Totality eclipses of the Sun

    CERN Document Server

    Littmann, Mark; Willcox, Ken

    2008-01-01

    A total eclipse of the Sun is the most awesome sight in the heavens. Totality: Eclipses of the Sun takes you to eclipses of the past, present, and future, and lets you see - and feel - why people travel to the ends of the Earth to observe them. - ;A total eclipse of the Sun is the most awesome sight in the heavens. Totality: Eclipses of the Sun takes you to eclipses of the past, present, and future, and lets you see - and feel - why people travel to the ends of the Earth to observe them. Totality: Eclipses of the Sun is the best guide and reference book on solar eclipses ever written. It explains: how to observe them; how to photograph and videotape them; why they occur; their history and mythology; and future eclipses - when and where to see them. Totality also tells the remarkable story of how eclipses shocked scientists, revealed the workings of the Sun, and made Einstein famous. And the book shares the experiences and advice of many veteran eclipse observers. Totality: Eclipses of the Sun is profusely ill...

  15. 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.

  16. Why Earth Science?

    Science.gov (United States)

    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…

  17. Earthing the human body influences physiologic processes.

    Science.gov (United States)

    Sokal, Karol; Sokal, Pawel

    2011-04-01

    This study was designed to answer the question: Does the contact of the human organism with the Earth via a copper conductor affect physiologic processes? Subjects and experiments: Five (5) experiments are presented: experiment 1-effect of earthing on calcium-phosphate homeostasis and serum concentrations of iron (N = 84 participants); experiment 2-effect of earthing on serum concentrations of electrolytes (N = 28); experiment 3-effect of earthing on thyroid function (N = 12); experiment 4-effect of earthing on glucose concentration (N = 12); experiment 5-effect of earthing on immune response to vaccine (N = 32). Subjects were divided into two groups. One (1) group of people was earthed, while the second group remained without contact with the Earth. Blood and urine samples were examined. Earthing of an electrically insulated human organism during night rest causes lowering of serum concentrations of iron, ionized calcium, inorganic phosphorus, and reduction of renal excretion of calcium and phosphorus. Earthing during night rest decreases free tri-iodothyronine and increases free thyroxine and thyroid-stimulating hormone. The continuous earthing of the human body decreases blood glucose in patients with diabetes. Earthing decreases sodium, potassium, magnesium, iron, total protein, and albumin concentrations while the levels of transferrin, ferritin, and globulins α1, α2, β, and γ increase. These results are statistically significant. Earthing the human body influences human physiologic processes. This influence is observed during night relaxation and during physical activity. Effect of the earthing on calcium-phosphate homeostasis is the opposite of that which occurs in states of weightlessness. It also increases the activity of catabolic processes. It may be the primary factor regulating endocrine and nervous systems.

  18. Earthing the Human Body Influences Physiologic Processes

    Science.gov (United States)

    Sokal, Karol

    2011-01-01

    Abstract Objectives This study was designed to answer the question: Does the contact of the human organism with the Earth via a copper conductor affect physiologic processes? Subjects and experiments Five (5) experiments are presented: experiment 1—effect of earthing on calcium–phosphate homeostasis and serum concentrations of iron (N = 84 participants); experiment 2—effect of earthing on serum concentrations of electrolytes (N = 28); experiment 3—effect of earthing on thyroid function (N = 12); experiment 4—effect of earthing on glucose concentration (N = 12); experiment 5—effect of earthing on immune response to vaccine (N = 32). Subjects were divided into two groups. One (1) group of people was earthed, while the second group remained without contact with the Earth. Blood and urine samples were examined. Results Earthing of an electrically insulated human organism during night rest causes lowering of serum concentrations of iron, ionized calcium, inorganic phosphorus, and reduction of renal excretion of calcium and phosphorus. Earthing during night rest decreases free tri-iodothyronine and increases free thyroxine and thyroid-stimulating hormone. The continuous earthing of the human body decreases blood glucose in patients with diabetes. Earthing decreases sodium, potassium, magnesium, iron, total protein, and albumin concentrations while the levels of transferrin, ferritin, and globulins α1, α2, β, and γ increase. These results are statistically significant. Conclusions Earthing the human body influences human physiologic processes. This influence is observed during night relaxation and during physical activity. Effect of the earthing on calcium–phosphate homeostasis is the opposite of that which occurs in states of weightlessness. It also increases the activity of catabolic processes. It may be the primary factor regulating endocrine and nervous systems. PMID:21469913

  19. 8 . TOTAL THRUST ON EARTH-RETAlNING STRUCTURES DUE ...

    African Journals Online (AJOL)

    The various surcharges along retaining walls may include vehicle loads ... be developed from ice formation due to pore water freezing. ... Figure 1 Lateral pressure against rigid wall due to ... value for the case of a line load is due to the effect.

  20. Theory of Earth

    Science.gov (United States)

    Anderson, D. L.

    2014-12-01

    Earth is an isolated, cooling planet that obeys the 2nd law. Interior dynamics is driven from the top, by cold sinking slabs. High-resolution broad-band seismology and geodesy has confirmed that mantle flow is characterized by narrow downwellings and ~20 broad slowly rising updrafts. The low-velocity zone (LVZ) consists of a hot melange of sheared peridotite intruded with aligned melt-rich lamellae that are tapped by intraplate volcanoes. The high temperature is a simple consequence of the thermal overshoot common in large bodies of convecting fluids. The transition zone consists of ancient eclogite layers that are displaced upwards by slabs to become broad passive, and cool, ridge feeding updrafts of ambient mantle. The physics that is overlooked in canonical models of mantle dynamics and geochemistry includes; the 2nd law, convective overshoots, subadiabaticity, wave-melt interactions, Archimedes' principle, and kinetics (rapid transitions allow stress-waves to interact with melting and phase changes, creating LVZs; sluggish transitions in cold slabs keep eclogite in the TZ where it warms up by extracting heat from mantle below 650 km, creating the appearance of slab penetration). Canonical chemical geodynamic models are the exact opposite of physics and thermodynamic based models and of the real Earth. A model that results from inverting the assumptions regarding initial and boundary conditions (hot origin, secular cooling, no external power sources, cooling internal boundaries, broad passive upwellings, adiabaticity and whole-mantle convection not imposed, layering and self-organization allowed) results in a thick refractory-yet-fertile surface layer, with ancient xenoliths and cratons at the top and a hot overshoot at the base, and a thin mobile D" layer that is an unlikely plume generation zone. Accounting for the physics that is overlooked, or violated (2nd law), in canonical models, plus modern seismology, undermines the assumptions and conclusions of these

  1. The Lifeworld Earth and a Modelled Earth

    Science.gov (United States)

    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…

  2. Rare earth sulfates

    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

  3. Rare earth germanates

    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

  4. Solar Flare Aimed at Earth

    Science.gov (United States)

    2002-01-01

    At the height of the solar cycle, the Sun is finally displaying some fireworks. This image from the Solar and Heliospheric Observatory (SOHO) shows a large solar flare from June 6, 2000 at 1424 Universal Time (10:24 AM Eastern Daylight Savings Time). Associated with the flare was a coronal mass ejection that sent a wave of fast moving charged particles straight towards Earth. (The image was acquired by the Extreme ultaviolet Imaging Telescope (EIT), one of 12 instruments aboard SOHO) Solar activity affects the Earth in several ways. The particles generated by flares can disrupt satellite communications and interfere with power transmission on the Earth's surface. Earth's climate is tied to the total energy emitted by the sun, cooling when the sun radiates less energy and warming when solar output increases. Solar radiation also produces ozone in the stratosphere, so total ozone levels tend to increase during the solar maximum. For more information about these solar flares and the SOHO mission, see NASA Science News or the SOHO home page. For more about the links between the sun and climate change, see Sunspots and the Solar Max. Image courtesy SOHO Extreme ultaviolet Imaging Telescope, ESA/NASA

  5. Linkages between the Urban Environment and Earth's Climate System

    Science.gov (United States)

    Shepherd, J. Marshall; Jin, Menglin

    2003-01-01

    Urbanization is one of the extreme cases of land use change. Although currently only 1.2% of the land is considered urban, the spatial coverage and density of cities are expected to rapidly increase in the near future. It is estimated that by the year 2025 60% of the world s population will live in cities (UNFP, 1999). Though urban areas are local in scale, human activity in urban environments has impacts at local, to global scale by changing atmospheric composition; impacting components of the water cycle; and modifying the carbon cycle 2nd ecosystems. For example, urban dwellers are undoubtedly familiar with "high" ozone pollution days, flash flooding in city streets, or heat stress on summer days. However, our understanding of urbanization on the total Earth-climate system is incomplete. Better understanding of how the Earth s weather, oceans, and land work together and the influence of the urban environment on this climate system is critical. This paper highlights some of the major and current issues involving interactions between urban environments and the Earth's climate system. It also captures some of the most current thinking and findings of the authors and key experts in the field.

  6. Total ankle joint replacement.

    Science.gov (United States)

    2016-02-01

    Ankle arthritis results in a stiff and painful ankle and can be a major cause of disability. For people with end-stage ankle arthritis, arthrodesis (ankle fusion) is effective at reducing pain in the shorter term, but results in a fixed joint, and over time the loss of mobility places stress on other joints in the foot that may lead to arthritis, pain and dysfunction. Another option is to perform a total ankle joint replacement, with the aim of giving the patient a mobile and pain-free ankle. In this article we review the efficacy of this procedure, including how it compares to ankle arthrodesis, and consider the indications and complications. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  7. Analyzing Solutions High in Total Dissolved Solids for Rare Earth Elements (REEs) Using Cation Exchange and Online Pre-Concentration with the seaFAST2 Unit; NETL-TRS-7-2017; NETL Technical Report Series; U.S. Department of Energy, National Energy Technology Laboratory: Albany, OR, 2017; p 32

    Energy Technology Data Exchange (ETDEWEB)

    Yang, J. [National Energy Technology Lab. (NETL), Albany, OR (United States); Oregon State Univ., Corvallis, OR (United States). College of Earth, Ocean, and Atmospheric Science; Torres, M. [Oregon State Univ., Corvallis, OR (United States). College of Earth, Ocean, and Atmospheric Science; Verba, C. [National Energy Technology Lab. (NETL), Albany, OR (United States); Oregon State Univ., Corvallis, OR (United States); Hakala, A. [National Energy Technology Lab. (NETL), Pittsburgh, PA, (United States)

    2017-08-01

    The accurate quantification of the rare earth element (REE) dissolved concentrations in natural waters are often inhibited by their low abundances in relation to other dissolved constituents such as alkali, alkaline earth elements, and dissolved solids. The high abundance of these constituents can suppress the overall analytical signal as well as create isobaric interferences on the REEs during analysis. Waters associated with natural gas operations on black shale plays are characterized by high salinities and high total dissolved solids (TDS) contents >150,000 mg/L. Methods used to isolate and quantify dissolved REEs in seawater were adapted in order to develop the capability of analyzing REEs in waters that are high in TDS. First, a synthetic fluid based on geochemical modelling of natural brine formation fluids was created within the Marcellus black shale with a TDS loading of 153,000 mg/L. To this solution, 1,000 ng/mL of REE standards was added based on preliminary analyses of experimental fluids reacted at high pressure and temperature with Marcellus black shale. These synthetic fluids were then run at three different dilution levels of 10, 100, and 1,000–fold dilutions through cation exchange columns using AG50-X8 exchange resin from Eichrom Industries. The eluent from the cation columns were then sent through a seaFAST2 unit directly connected to an inductively coupled plasma mass spectrometer (ICP-MS) to analyze the REEs. Percent recoveries of the REEs ranged from 80–110% and fell within error for the external reference standard used and no signal suppression or isobaric interferences on the REEs were observed. These results demonstrate that a combined use of cation exchange columns and seaFAST2 instrumentation are effective in accurately quantifying the dissolved REEs in fluids that are >150,000 mg/L in TDS and have Ba:Eu ratios in excess of 380,000.

  8. NASA Earth Exchange (NEX)

    Data.gov (United States)

    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....

  9. Population: Census Bureau Total Estimates (2010-2012)

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — Total population estimates are estimates of the total number of residents living in an area on July 1 of each year. The Census Bureau’s Population Division produces...

  10. Journal of Earth System Science | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Earth System Science; Volume 125; Issue 5 ... In the upper layer, themaximum shear stress is high in the Zhangjiakou area, whereas in the ... School of Resources and Geoscience, China University of Mining and ...

  11. Biological Extinction in Earth History

    Science.gov (United States)

    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.

  12. Biological extinction in earth history

    Science.gov (United States)

    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.

  13. Journal of Earth System Science | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Earth System Science. Anup Saha. Articles written in Journal of Earth System Science. Volume 125 Issue 4 June 2016 pp 885-895. Effect of irregularity on torsional surface waves in an initially stressed anisotropic porous layer sandwiched between homogeneous and non-homogeneous half- ...

  14. Journal of Earth System Science | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Earth System Science. Ju Wei. Articles written in Journal of Earth System Science. Volume 125 Issue 5 July 2016 pp 1021-1031. Tectonic stress accumulation in Bohai–Zhangjiakou Seismotectonic Zone based on 3D visco-elastic modelling · Ju Wei Sun Weifeng Ma Xiaojing Jiang Hui.

  15. Mission to Planet Earth

    Science.gov (United States)

    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.

  16. Mission to Planet Earth

    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

  17. 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

  18. Space exercise and Earth benefits.

    Science.gov (United States)

    Macias, Brandon R; Groppo, Eli R; Eastlack, Robert K; Watenpaugh, Donald E; Lee, Stuart M C; Schneider, Suzanne M; Boda, Wanda L; Smith, Scott M; Cutuk, Adnan; Pedowitz, Robert A; Meyer, R Scott; Hargens, Alan R

    2005-08-01

    The detrimental impact of long duration space flight on physiological systems necessitates the development of exercise countermeasures to protect work capabilities in gravity fields of Earth, Moon and Mars. The respective rates of physiological deconditioning for different organ systems during space flight has been described as a result of data collected during and after missions on the Space Shuttle, International Space Station, Mir, and bed rest studies on Earth. An integrated countermeasure that simulates the body's hydrostatic pressure gradient, provides mechanical stress to the bones and muscles, and stimulates the neurovestibular system may be critical for maintaining health and well being of crew during long-duration space travel, such as a mission to Mars. Here we review the results of our studies to date of an integrated exercise countermeasure for space flight, lower body negative pressure (LBNP) treadmill exercise, and potential benefits of its application to athletic training on Earth. Additionally, we review the benefits of Lower Body Positive Pressure (LBPP) exercise for rehabilitation of postoperative patients. Presented first are preliminary data from a 30-day bed rest study evaluating the efficacy of LBNP exercise as an integrated exercise countermeasure for the deconditioning effects of microgravity. Next, we review upright LBNP exercise as a training modality for athletes by evaluating effects on the cardiovascular system and gait mechanics. Finally, LBPP exercise as a rehabilitation device is examined with reference to gait mechanics and safety in two groups of postoperative patients.

  19. Might electrical earthing affect convection of light

    International Nuclear Information System (INIS)

    Budrikis, Z.L.

    1982-01-01

    Partial convection of light by moving media was predicted by Fresnel and verified by Fizeau, Zeeman and others. It is accepted as an important argument in favour of the Special Theory of Relativity. The suggestion is made here that the convection is partial only when the propagating medium is moved with respect to its electrically earthed surroundings and that it would be total if an earthed shield was co-moving with the medium. This is based on a reinterpretation of Maxwell's equations wherein they are seen as macroscopic relationships that are in each case valid only in respect of a particular inertial frame of reference, the local electrical earth frame. (Auth.)

  20. 2004 Top 10 Chinese Rare Earth Events

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    1. Management to the Investment in Rare Earth IndustryConfirmedIn July 2004, "Decision on the Reform in Investment System" was formally publicized by the State Council of the People's Republic of China. The fifth item in the Decision stipulates that ore exploitation, smelting & separation and rare earth deep-processed projects with total investment over RMB¥100 million should be approved by the investment governing department of the State Council, and that other

  1. 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

  2. The Australian Computational Earth Systems Simulator

    Science.gov (United States)

    Mora, P.; Muhlhaus, H.; Lister, G.; Dyskin, A.; Place, D.; Appelbe, B.; Nimmervoll, N.; Abramson, D.

    2001-12-01

    Numerical simulation of the physics and dynamics of the entire earth system offers an outstanding opportunity for advancing earth system science and technology but represents a major challenge due to the range of scales and physical processes involved, as well as the magnitude of the software engineering effort required. However, new simulation and computer technologies are bringing this objective within reach. Under a special competitive national funding scheme to establish new Major National Research Facilities (MNRF), the Australian government together with a consortium of Universities and research institutions have funded construction of the Australian Computational Earth Systems Simulator (ACcESS). The Simulator or computational virtual earth will provide the research infrastructure to the Australian earth systems science community required for simulations of dynamical earth processes at scales ranging from microscopic to global. It will consist of thematic supercomputer infrastructure and an earth systems simulation software system. The Simulator models and software will be constructed over a five year period by a multi-disciplinary team of computational scientists, mathematicians, earth scientists, civil engineers and software engineers. The construction team will integrate numerical simulation models (3D discrete elements/lattice solid model, particle-in-cell large deformation finite-element method, stress reconstruction models, multi-scale continuum models etc) with geophysical, geological and tectonic models, through advanced software engineering and visualization technologies. When fully constructed, the Simulator aims to provide the software and hardware infrastructure needed to model solid earth phenomena including global scale dynamics and mineralisation processes, crustal scale processes including plate tectonics, mountain building, interacting fault system dynamics, and micro-scale processes that control the geological, physical and dynamic

  3. 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...

  4. Geomagnetic field of earth

    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)

  5. 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

  6. Capturing near-Earth asteroids around Earth

    Science.gov (United States)

    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

  7. Non-rocket Earth-Moon transport system

    Science.gov (United States)

    Bolonkin, Alexander

    2003-06-01

    This paper proposes a new transportation system for travel between Earth and Moon. This transportation system uses mechanical energy transfer and requires only minimal energy, using an engine located on Earth. A cable directly connects a pole of the Earth through a drive station to the lunar surface_ The equation for an optimal equal stress cable for complex gravitational field of Earth-Moon has been derived that allows significantly lower cable masses. The required strength could be provided by cables constructed of carbon nanotubes or carbon whiskers. Some of the constraints on such a system are discussed.

  8. Thermodynamics of the Earth

    International Nuclear Information System (INIS)

    Stacey, Frank D

    2010-01-01

    Applications of elementary thermodynamic principles to the dynamics of the Earth lead to robust, quantitative conclusions about the tectonic effects that arise from convection. The grand pattern of motion conveys deep heat to the surface, generating mechanical energy with a thermodynamic efficiency corresponding to that of a Carnot engine operating over the adiabatic temperature gradient between the heat source and sink. Referred to the total heat flux derived from the Earth's silicate mantle, the efficiency is 24% and the power generated, 7.7 x 10 12 W, causes all the material deformation apparent as plate tectonics and the consequent geological processes. About 3.5% of this is released in seismic zones but little more than 0.2% as seismic waves. Even major earthquakes are only localized hiccups in this motion. Complications that arise from mineral phase transitions can be used to illuminate details of the motion. There are two superimposed patterns of convection, plate subduction and deep mantle plumes, driven by sources of buoyancy, negative and positive respectively, at the top and bottom of the mantle. The patterns of motion are controlled by the viscosity contrasts (>10 4 : 1) at these boundaries and are self-selected as the least dissipative mechanisms of heat transfer for convection in a body with very strong viscosity variation. Both are subjects of the thermodynamic efficiency argument. Convection also drives the motion in the fluid outer core that generates the geomagnetic field, although in that case there is an important energy contribution by compositional separation, as light solute is rejected by the solidifying inner core and mixed into the outer core, a process referred to as compositional convection. Uncertainty persists over the core energy balance because thermal conduction is a drain on core energy that has been a subject of diverse estimates, with attendant debate over the need for radiogenic heat in the core. The geophysical approach to

  9. EARTH FROM SPACE

    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.

  10. Earth and Universe

    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.

  11. Hands On Earth Science.

    Science.gov (United States)

    Weisgarber, Sherry L.; Van Doren, Lisa; Hackathorn, Merrianne; Hannibal, Joseph T.; Hansgen, Richard

    This publication is a collection of 13 hands-on activities that focus on earth science-related activities and involve students in learning about growing crystals, tectonics, fossils, rock and minerals, modeling Ohio geology, geologic time, determining true north, and constructing scale-models of the Earth-moon system. Each activity contains…

  12. Introducing Earth's Orbital Eccentricity

    Science.gov (United States)

    Oostra, Benjamin

    2015-01-01

    Most students know that planetary orbits, including Earth's, are elliptical; that is Kepler's first law, and it is found in many science textbooks. But quite a few are mistaken about the details, thinking that the orbit is very eccentric, or that this effect is somehow responsible for the seasons. In fact, the Earth's orbital eccentricity is…

  13. Earth System Science Project

    Science.gov (United States)

    Rutherford, Sandra; Coffman, Margaret

    2004-01-01

    For several decades, science teachers have used bottles for classroom projects designed to teach students about biology. Bottle projects do not have to just focus on biology, however. These projects can also be used to engage students in Earth science topics. This article describes the Earth System Science Project, which was adapted and developed…

  14. Stress Management: Job Stress

    Science.gov (United States)

    Healthy Lifestyle Stress management Job stress can be all-consuming — but it doesn't have to be. Address your triggers, keep perspective and ... stress triggers, it's often helpful to improve time management skills — especially if you tend to feel overwhelmed ...

  15. Childhood Stress

    Science.gov (United States)

    ... Safe Videos for Educators Search English Español Childhood Stress KidsHealth / For Parents / Childhood Stress What's in this ... and feel stress to some degree. Sources of Stress Stress is a function of the demands placed ...

  16. New Conditions for a Total Neutrino Conversion in a Medium

    OpenAIRE

    Chizhov, M. V.; Petcov, S. T.

    1999-01-01

    A new effect of total neutrino conversion is possible when neutrino propagates through multi-layer medium of nonperiodic constant density layers. The effect can take place in the oscillations in the Earth of the Earth-core-crossing solar and atmospheric neutrinos.

  17. Earth as art three

    Science.gov (United States)

    ,

    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!

  18. Earth Science Informatics - Overview

    Science.gov (United States)

    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

  19. Rare Earth Garnet Selective Emitter

    Science.gov (United States)

    Lowe, Roland A.; Chubb, Donald L.; Farmer, Serene C.; Good, Brian S.

    1994-01-01

    impurities, in the development of solid state laser crystals. Doping, dependent on the particular ion and crystal structure, may be as high as 100 at. % (complete substitution of yttrium ion with the rare earth ion). These materials have high melting points, 1940 C for YAG (Yttrium Aluminum Garnet), and low emissivity in the near infrared making them excellent candidates for a thin film selective emitter. As previously stated, the spectral emittance of a rare earth emitter is characterized by one or more well defined emission bands. Outside the emission band the emittance(absorptance) is much lower. Therefore, it is expected that emission outside the band for a thin film selective emitter will be dominated by the emitter substrate. For an efficient emitter (power in the emission band/total emitted power) the substrate must have low emittance, epsilon(sub S). This paper presents normal spectral emittance, epsilon(sub lambda), measurements of holmium(Ho) and erbium (Er) doped YAG thin film selective emitters at (1500 K), and compares those results with the theoretical spectral emittance.

  20. Rare earth germanates

    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

  1. Project Earth Science

    CERN Document Server

    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.

  2. Earth formation porosity log

    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

  3. Earth before life.

    Science.gov (United States)

    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.

  4. Earth's variable rotation

    Science.gov (United States)

    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.

  5. Near Earth Objects

    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...

  6. Earth study from space

    Science.gov (United States)

    Sidorenko, A. V.

    1981-01-01

    The significance that space studies are making to all Earth sciences in the areas of geography, geodesy, cartography, geology, meteorology, oceanology, agronomy, and ecology is discussed. It is predicted that cosmonautics will result in a revolution in science and technology.

  7. Earth's electric field

    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

  8. Near Earth Asteroid Scout

    Data.gov (United States)

    National Aeronautics and Space Administration — Near-Earth Asteroid Scout, or NEA Scout, is a 6U CubeSat developed jointly between NASA’s Marshall Space Flight Center and the Jet Propulsion Laboratory. NASA...

  9. Gambling with the earth

    CERN Multimedia

    Muir, H

    2000-01-01

    The probability that dangerous Earth-devouring particles will be born at a new accelerator in the US may be tiny, but scientists have played down the devastating potential costs in their risk assessments according to a physicist (1 page).

  10. Jupiter and planet Earth

    International Nuclear Information System (INIS)

    1975-01-01

    The evolution of Jupiter and Earth are discussed along with their atmospheres, the radiation belts around both planets, natural satellites, the evolution of life, and the Pioneer 10. Educational study projects are also included

  11. Earth retaining structures manual

    Science.gov (United States)

    2009-10-29

    The objectives of this policy are to obtain statewide uniformity, establish standard : procedures and delineate responsibility for the preparation and review of plans, : design and construction control of earth retaining structures. In addition, it i...

  12. Earliest life on earth

    CERN Document Server

    Golding, Suzanne D

    2010-01-01

    This volume integrates the latest findings on earliest life forms, identified and characterized in some of the oldest rocks on Earth. It places emphasis on the integration of analytical methods with observational techniques and experimental simulations.

  13. Uncertainty analysis of atmospheric friction torque on the solid Earth

    Directory of Open Access Journals (Sweden)

    Haoming Yan

    2016-05-01

    Full Text Available The wind stress acquired from European Centre for Medium-Range Weather Forecasts (ECMWF, National Centers for Environmental Prediction (NCEP climate models and QSCAT satellite observations are analyzed by using frequency-wavenumber spectrum method. The spectrum of two climate models, i.e., ECMWF and NCEP, is similar for both 10 m wind data and model output wind stress data, which indicates that both the climate models capture the key feature of wind stress. While the QSCAT wind stress data shows the similar characteristics with the two climate models in both spectrum domain and the spatial distribution, but with a factor of approximately 1.25 times larger than that of climate models in energy. These differences show the uncertainty in the different wind stress products, which inevitably cause the atmospheric friction torque uncertainties on solid Earth with a 60% departure in annual amplitude, and furtherly affect the precise estimation of the Earth's rotation.

  14. Optimal Safety EarthingEarth 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 ...

  15. Partial radiogenic heat model for Earth revealed by geoneutrino measurements

    NARCIS (Netherlands)

    Abe, S.; et al., [Unknown; Decowski, M.P.

    2011-01-01

    The Earth has cooled since its formation, yet the decay of radiogenic isotopes, and in particular uranium, thorium and potassium, in the planet’s interior provides a continuing heat source. The current total heat flux from the Earth to space is 44.2±1.0 TW, but the relative contributions from

  16. Journal of Earth System Science | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Earth System Science. P C S Devara. Articles written in Journal of Earth System Science. Volume 112 Issue 2 June 2003 pp 205-221. Study of total column atmospheric aerosol optical depth, ozone and precipitable water content over Bay of Bengal during BOBMEX-99 · K K Dani R S ...

  17. Outline of the earth simulator project

    International Nuclear Information System (INIS)

    Tani, Keiji

    2000-01-01

    The Science and Technology Agency of Japan has proposed a project to promote studies for global change prediction by an integrated three-in-one research and development approach: earth observation, basic research, and computer simulation. As part of the project, we are developing an ultra-fast computer, the 'Earth Simulator', with a sustained speed of more than 5 TFLOPS for an atmospheric circulation code. The 'Earth Simulator' is a MIMD type distributed memory parallel system in which 640 processor nodes are connected via fast single-stage crossbar network. Earth node consists of 8 vector-type arithmetic processors which are tightly connected via shared memory. The peak performance of the total system is 40 TFLOPS. As part of the development of basic software system, we are developing an operation supporting software system what is called a 'center routine'. We are going to use an archival system as a main storage of user files. Therefore, the most important function of the center routine is the optimal scheduling of not only submitted batch jobs but also user files necessary for them. All the design and R and D works for both hardware and basic software systems have been completed during the last three fiscal years, FY97, 98 and 99. The manufacture of the hardware system and the development of the center routine are underway. Facilities necessary for the Earth Simulator including buildings are also under construction. The total system will be completed in the spring of 2002. (author)

  18. Stress Management

    Science.gov (United States)

    Healthy Lifestyle Stress management By Mayo Clinic Staff Stress basics Stress is a normal psychological and physical reaction to the demands of life. ... some people's alarm systems rarely shut off. Stress management gives you a range of tools to reset ...

  19. Manage Stress

    Science.gov (United States)

    ... Manage Stress Print This Topic En español Manage Stress Browse Sections The Basics Overview Signs and Health ... and Health Effects What are the signs of stress? When people are under stress, they may feel: ...

  20. Stress Incontinence

    Science.gov (United States)

    Stress incontinence Overview Urinary incontinence is the unintentional loss of urine. Stress incontinence happens when physical movement or activity — such ... coughing, sneezing, running or heavy lifting — puts pressure (stress) on your bladder. Stress incontinence is not related ...

  1. Total parenteral nutrition - infants

    Science.gov (United States)

    ... medlineplus.gov/ency/article/007239.htm Total parenteral nutrition - infants To use the sharing features on this page, please enable JavaScript. Total parenteral nutrition (TPN) is a method of feeding that bypasses ...

  2. Total parenteral nutrition

    Science.gov (United States)

    ... medlineplus.gov/ency/patientinstructions/000177.htm Total parenteral nutrition To use the sharing features on this page, please enable JavaScript. Total parenteral nutrition (TPN) is a method of feeding that bypasses ...

  3. Technique of total thyroidectomy

    International Nuclear Information System (INIS)

    Rao, R.S.

    1999-01-01

    It is essential to define the various surgical procedures that are carried out for carcinoma of the thyroid gland. They are thyroid gland, subtotal lobectomy, total thyroidectomy and near total thyroidectomy

  4. Total iron binding capacity

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/003489.htm Total iron binding capacity To use the sharing features on this page, please enable JavaScript. Total iron binding capacity (TIBC) is a blood test to ...

  5. The Sun and Earth

    Science.gov (United States)

    Gopalswamy, Natchimuthuk

    2012-01-01

    Thus the Sun forms the basis for life on Earth via the black body radiation it emits. The Sun also emits mass in the form of the solar wind and the coronal mass ejections (CMEs). Mass emission also occurs in the form of solar energetic particles (SEPs), which happens during CMEs and solar flares. Both the mass and electromagnetic energy output of the Sun vary over a wide range of time scales, thus introducing disturbances on the space environment that extends from the Sun through the entire heliosphere including the magnetospheres and ionospheres of planets and moons of the solar system. Although our habitat is located in the neutral atmosphere of Earth, we are intimately connected to the non-neutral space environment starting from the ionosphere to the magnetosphere and to the vast interplanetary space. The variability of the solar mass emissions results in the interaction between the solar wind plasma and the magnetospheric plasma leading to huge disturbances in the geospace. The Sun ionizes our atmosphere and creates the ionosphere. The ionosphere can be severely disturbed by the transient energy input from solar flares and the solar wind during geomagnetic storms. The complex interplay between Earth's magnetic field and the solar magnetic field carried by the solar wind presents varying conditions that are both beneficial and hazardous to life on earth. This seminar presents some of the key aspects of this Sun-Earth connection that we have learned since the birth of space science as a scientific discipline some half a century ago.

  6. Earth and planetary sciences

    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

  7. Modeling the earth system

    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.

  8. The Earth System Model

    Science.gov (United States)

    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.

  9. Rare earths and actinides

    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.)

  10. Reservoir stress from microseismic source mechanisms

    Czech Academy of Sciences Publication Activity Database

    Staněk, František; Jechumtálová, Z.; Eisner, L.

    2015-01-01

    Roč. 34, č. 8 (2015), od 890 do 893, 895 ISSN 1070-485X Institutional support: RVO:67985891 Keywords : microseismic monitoring * source mechanisms * stress Subject RIV: DC - Siesmology, Volcanology, Earth Structure

  11. Total well dominated trees

    DEFF Research Database (Denmark)

    Finbow, Arthur; Frendrup, Allan; Vestergaard, Preben D.

    cardinality then G is a total well dominated graph. In this paper we study composition and decomposition of total well dominated trees. By a reversible process we prove that any total well dominated tree can both be reduced to and constructed from a family of three small trees....

  12. Cermets based on rhenium and rare earth element oxides

    International Nuclear Information System (INIS)

    Varfolomeev, M.B.; Velichko, A.V.; Zajtseva, L.L.; Shishkov, N.V.

    1977-01-01

    The reduction of perrhenates of rare earth elements and of yttrium by hydrogen and the subsequent sintering have yielded cermets based on rhenium and rare earth element oxides inherent in which are more disperse and homogeneous structures than those of the ''molecular'' rare earth element-Tc cermets. The dispersity of cermets increases in the rare earth elements series from La to Lu. The microhardness of the Re phase in cermets is 490 kgf/mm 2 ; the total microhardness of a cermet is substantially higher

  13. Measuring Earth's Radiation Budget from the Vicinity of the Moon

    Science.gov (United States)

    Swartz, W. H.; Lorentz, S. R.; Erlandson, R. E.; Cahalan, R. F.; Huang, P. M.

    2018-02-01

    We propose to measure Earth's radiation budget (integrated total and solar-reflected shortwave) using broadband radiometers and other technology demonstrated in space. The instrument is compact, autonomous, and has modest resource requirements.

  14. Journal of Earth System Science | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Earth System Science; Volume 120; Issue 4 ... a human adjustment scenario, which assumes future improvements in water conservation ... Similarly, a severe drought would lead to a total streamflow loss of < 80%.

  15. Earth's Trojan asteroid.

    Science.gov (United States)

    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.

  16. How Big is Earth?

    Science.gov (United States)

    Thurber, Bonnie B.

    2015-08-01

    How Big is Earth celebrates the Year of Light. Using only the sunlight striking the Earth and a wooden dowel, students meet each other and then measure the circumference of the earth. Eratosthenes did it over 2,000 years ago. In Cosmos, Carl Sagan shared the process by which Eratosthenes measured the angle of the shadow cast at local noon when sunlight strikes a stick positioned perpendicular to the ground. By comparing his measurement to another made a distance away, Eratosthenes was able to calculate the circumference of the earth. How Big is Earth provides an online learning environment where students do science the same way Eratosthenes did. A notable project in which this was done was The Eratosthenes Project, conducted in 2005 as part of the World Year of Physics; in fact, we will be drawing on the teacher's guide developed by that project.How Big Is Earth? expands on the Eratosthenes project by providing an online learning environment provided by the iCollaboratory, www.icollaboratory.org, where teachers and students from Sweden, China, Nepal, Russia, Morocco, and the United States collaborate, share data, and reflect on their learning of science and astronomy. They are sharing their information and discussing their ideas/brainstorming the solutions in a discussion forum. There is an ongoing database of student measurements and another database to collect data on both teacher and student learning from surveys, discussions, and self-reflection done online.We will share our research about the kinds of learning that takes place only in global collaborations.The entrance address for the iCollaboratory is http://www.icollaboratory.org.

  17. Teaching earth science

    Science.gov (United States)

    Alpha, Tau Rho; Diggles, Michael F.

    1998-01-01

    This CD-ROM contains 17 teaching tools: 16 interactive HyperCard 'stacks' and a printable model. They are separated into the following categories: Geologic Processes, Earthquakes and Faulting, and Map Projections and Globes. A 'navigation' stack, Earth Science, is provided as a 'launching' place from which to access all of the other stacks. You can also open the HyperCard Stacks folder and launch any of the 16 stacks yourself. In addition, a 17th tool, Earth and Tectonic Globes, is provided as a printable document. Each of the tools can be copied onto a 1.4-MB floppy disk and distributed freely.

  18. Rare (Earth Elements [score

    Directory of Open Access Journals (Sweden)

    Camilo Méndez

    2014-12-01

    Full Text Available Rare (Earth Elements is a cycle of works for solo piano. The cycle was inspired by James Dillon’s Book of Elements (Vol. I-V. The complete cycle will consist of 14 pieces; one for each selected rare (earth element. The chosen elements are Neodymium, Erbium, Tellurium, Hafnium, Tantalum, Technetium, Indium, Dysprosium, Lanthanium, Cerium, Europium, Terbium, Yttrium and Darmstadtium. These elements were selected due to their special atomic properties that in many cases make them extremely valuable for the development of new technologies, and also because of their scarcity. To date, only 4 works have been completed Yttrium, Technetium, Indium and Tellurium.

  19. IR and the Earth

    DEFF Research Database (Denmark)

    Corry, Olaf; Stevenson, Hayley

    2017-01-01

    , in the end, one finite interconnected space. Together these two starting points make for the basic conundrum of Inter- national Relations and the Earth: how does a divided world live on a single globe? This introduction first provides an overview of the recent rise of ‘the environment’ in international......, ‘what has the environment ever done for IR?’, before the plan for the rest of the book sketches the content and direction of the ensuing chapters that explore the problematique of International Relations and the Earth....

  20. The Earth's Plasmasphere

    Science.gov (United States)

    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

  1. Rapid analysis of some rare earth magnets

    International Nuclear Information System (INIS)

    Raoot, K.N.; Raoot, Sarala; Rukmani Desikan, N.

    1978-01-01

    A simple complexometric method for the quick analysis of the constituent elements in some quaternary rare earth magnets of the type RE-Co-Cu-Fe and RE-Ni-Cu-Fe is described. The technique is based on a total titration, subsequent release of EDTA from rare earth with ammonium fluoride and that from copper (II) with ascorbic acid and thiourea followed by determination of the excess and liberated EDTA by lead nitrate in a weak acid medium using xylenol orange indicator. In another, aliquot iron (III) and rare earth are first masked with sodium fluoride, and copper (II) with ascorbic acid and thiourea before cobalt (II) or nickel (II) is estimated by back titration. Iron is calculated by difference. The new method yields accurate and reproducible results with error not exceeding 1%. A set of three samples can conveniently be analysed in two hours. (author)

  2. Rapid analysis of some rare earth magnets

    Energy Technology Data Exchange (ETDEWEB)

    Raoot, K N; Raoot, S; Rukmani Desikan, N [Defence Metallurgical Research Lab., Hyderabad (India)

    1978-12-01

    A simple complexometric method for the quick analysis of the constituent elements in some quaternary rare earth magnets of the type RE-Co-Cu-Fe and RE-Ni-Cu-Fe is described. The technique is based on a total titration, subsequent release of EDTA from rare earth with ammonium fluoride and that from copper (II) with ascorbic acid and thiourea followed by determination of the excess and liberated EDTA by lead nitrate in a weak acid medium using xylenol orange indicator. In another, aliquot iron (III) and rare earth are first masked with sodium fluoride, and copper (II) with ascorbic acid and thiourea before cobalt (II) or nickel (II) is estimated by back titration. Iron is calculated by difference. The new method yields accurate and reproducible results with error not exceeding 1%. A set of three samples can conveniently be analysed in two hours.

  3. Earth Sciences report, 1989--1990

    International Nuclear Information System (INIS)

    Younker, L.W.; Peterson, S.J.; Price, M.E.

    1991-03-01

    The Earth Sciences Department at Lawrence Livermore National Laboratory (LLNL) conducts work in support of the Laboratory's energy, defense, environmental, and basic research programs. The Department comprises more than 100 professional scientific personnel spanning a variety of subdisciplines: geology, seismology, physics, geophysics, geochemistry, geohydrology, chemical engineering, and mechanical engineering. Resident technical support groups add significant additional technical expertise, including Containment Engineering, Computations, Electronic Engineering, Mechanical Engineering, Chemistry and Materials Science, and Technical Information. In total, approximately 180 professional scientists and engineers are housed in the Earth Sciences Department, making it one of the largest geo-science research groups in the nation. Previous Earth Sciences reports have presented an outline of the technical capabilities and accomplishments of the groups within the Department. In this FY 89/90 Report, we have chosen instead to present twelve of our projects in full-length technical articles. This Overview introduces those articles and highlights other significant research performed during this period

  4. Earth Sciences report, 1989--1990

    Energy Technology Data Exchange (ETDEWEB)

    Younker, L.W.; Peterson, S.J.; Price, M.E. (eds.)

    1991-03-01

    The Earth Sciences Department at Lawrence Livermore National Laboratory (LLNL) conducts work in support of the Laboratory's energy, defense, environmental, and basic research programs. The Department comprises more than 100 professional scientific personnel spanning a variety of subdisciplines: geology, seismology, physics, geophysics, geochemistry, geohydrology, chemical engineering, and mechanical engineering. Resident technical support groups add significant additional technical expertise, including Containment Engineering, Computations, Electronic Engineering, Mechanical Engineering, Chemistry and Materials Science, and Technical Information. In total, approximately 180 professional scientists and engineers are housed in the Earth Sciences Department, making it one of the largest geo-science research groups in the nation. Previous Earth Sciences reports have presented an outline of the technical capabilities and accomplishments of the groups within the Department. In this FY 89/90 Report, we have chosen instead to present twelve of our projects in full-length technical articles. This Overview introduces those articles and highlights other significant research performed during this period.

  5. EarthScope Education and Outreach: Accomplishments and Emerging Opportunities

    Science.gov (United States)

    Robinson, S.; Ellins, K. K.; Semken, S. C.; Arrowsmith, R.

    2014-12-01

    EarthScope's Education and Outreach (E&O) program aims to increase public awareness of Earth science and enhance geoscience education at the K-12 and college level. The program is distinctive among major geoscience programs in two ways. First, planning for education and public engagement occurred in tandem with planning for the science mission. Second, the NSF EarthScope program includes funding support for education and outreach. In this presentation, we highlight key examples of the program's accomplishments and identify emerging E&O opportunities. E&O efforts have been collaboratively led by the EarthScope National Office (ESNO), IRIS, UNAVCO, the EarthScope Education and Outreach Subcommittee (EEOSC) and PI-driven EarthScope projects. Efforts by the EEOSC, guided by an EarthScope Education and Outreach Implementation Plan that is periodically updated, focus EarthScope E&O. EarthScope demonstrated early success in engaging undergraduate students (and teachers) in its mission through their involvement in siting USArray across the contiguous U.S. Funded E&O programs such as TOTLE, Illinois EarthScope, CEETEP (for K-12), InTeGrate and GETSI (for undergraduates) foster use of freely available EarthScope data and research findings. The Next Generation Science Standards, which stress science and engineering practices, offer an opportunity for alignment with existing EarthScope K-12 educational resources, and the EEOSC recommends focusing efforts on this task. The EEOSC recognizes the rapidly growing use of mobile smart devices by the public and in formal classrooms, which bring new opportunities to connect with the public and students. This will capitalize on EarthScope's already prominent social media presence, an effort that developed to accomplish one of the primary goals of the EarthScope E&O Implementation Plan to "Create a high-profile public identity for EarthScope" and to "Promote science literacy and understanding of EarthScope among all audiences through

  6. "Galileo Calling Earth..."

    Science.gov (United States)

    National Aeronautics and Space Administration, Washington, DC.

    This guide presents an activity for helping students understand how data from the Galileo spacecraft is sent to scientists on earth. Students are asked to learn about the concepts of bit-rate and resolution and apply them to the interpretation of images from the Galileo Orbiter. (WRM)

  7. Bones of the Earth

    Science.gov (United States)

    Correa, Jose Miguel

    2014-01-01

    The film "Bones of the Earth" (Riglin, Cunninham & Correa, 2014) is an experience in collective inquiry and visual creation based on arts-based research. Starting from the meeting of different subjectivities and through dialogue, planning, shooting and editing, an audiovisual text that reconstructs a reflexive process of collective…

  8. Our bubbling Earth

    NARCIS (Netherlands)

    Schuiling, R.D.

    2005-01-01

    In several places on earth large volumes of gas are seen to escape. These gases are usually dominated by CO2. The emissions are associated with volcanic activity, and are attributed to magma degassing. It will be shown that in the case of Milos this explanation is unacceptable for quantitative

  9. Cosmic rays on earth

    International Nuclear Information System (INIS)

    Allkofer, O.C.; Grieder, P.K.F.

    1984-01-01

    A data collection is presented that covers cosmic rays on earth. Included are all relevant data on flux and intensity measurements, energy spectra, and related data of all primary and secondary components of the cosmic radiation at all levels in the atmosphere, at sea level and underground. In those cases where no useful experimental data have been available, theoretical predictions were substituted. (GSCH)

  10. Earth as art 4

    Science.gov (United States)

    ,

    2016-03-29

    Landsat 8 is the latest addition to the long-running series of Earth-observing satellites in the Landsat program that began in 1972. The images featured in this fourth installment of the Earth As Art collection were all acquired by Landsat 8. They show our planet’s diverse landscapes with remarkable clarity.Landsat satellites see the Earth as no human can. Not only do they acquire images from the vantage point of space, but their sensors record infrared as well as visible wavelengths of light. The resulting images often reveal “hidden” details of the Earth’s land surface, making them invaluable for scientific research.As with previous Earth As Art exhibits, these Landsat images were selected solely for 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. What do you see in these unique glimpses of the Earth’s continents, islands, and coastlines?

  11. Google Earth Science

    Science.gov (United States)

    Baird, William H.; Padgett, Clifford W.; Secrest, Jeffery A.

    2015-01-01

    Google Earth has made a wealth of aerial imagery available online at no cost to users. We examine some of the potential uses of that data in illustrating basic physics and astronomy, such as finding the local magnetic declination, using landmarks such as the Washington Monument and Luxor Obelisk as gnomons, and showing how airport runways get…

  12. How life shaped Earth.

    Science.gov (United States)

    Gross, Michael

    2015-10-05

    Earth is much more complex than all the other solar system objects that we know. Thanks to its rich and diverse geology, our planet can offer habitats to a wide range of living species. Emerging insights suggest that this is not just a happy coincidence, but that life itself has in many ways helped to shape the planet.

  13. Magnetic rare earth superlattices

    DEFF Research Database (Denmark)

    Majkrzak, C.F.; Kwo, J.; Hong, M.

    1991-01-01

    Advances in molecular beam epitaxy deposition techniques have recently made it possible to grow, an atomic plane at a time, single crystalline superlattices composed of alternating layers of a magnetic rare earth, such as Gd, Dy, Ho, or Er, and metallic Y, which has an identical chemical structure...

  14. Understanding Earth's Albedo Effect

    Science.gov (United States)

    Fidler, Chuck

    2012-01-01

    Earth and space science in the middle school classroom are composed of intricately intertwined sets of conceptual systems (AAAS 1993; NRC 1996). Some systems of study, such as the water and rock cycles, are quite explicit and often found as stand-alone middle school science units. Other phenomena are not so apparent, yet they play an extremely…

  15. Earth Science Misconceptions.

    Science.gov (United States)

    Philips, William C.

    1991-01-01

    Presented is a list of over 50 commonly held misconceptions based on a literature review found in students and adults. The list covers earth science topics such as space, the lithosphere, the biosphere, the atmosphere, the hydrosphere, and the cryosphere. (KR)

  16. The earths innermost core

    International Nuclear Information System (INIS)

    Nanda, J.N.

    1989-01-01

    A new earth model is advanced with a solid innermost core at the centre of the Earth where elements heavier than iron, over and above what can be retained in solution in the iron core, are collected. The innermost core is separated from the solid iron-nickel core by a shell of liquid copper. The innermost core has a natural vibration measured on the earth's surface as the long period 26 seconds microseisms. The earth was formed initially as a liquid sphere with a relatively thin solid crust above the Byerly discontinuity. The trace elements that entered the innermost core amounted to only 0.925 ppm of the molten mass. Gravitational differentiation must have led to the separation of an explosive thickness of pure 235 U causing a fission explosion that could expel beyond the Roche limit a crustal scab which would form the centre piece of the moon. A reservoir of helium floats on the liquid copper. A small proportion of helium-3, a relic of the ancient fission explosion present there will spell the exciting magnetic field. The field is stable for thousands of years because of the presence of large quantity of helium-4 which accounts for most of the gaseous collisions that will not disturb the atomic spin of helium-3 atoms. This field is prone to sudden reversals after long periods of stability. (author). 14 refs

  17. Rare earths production and marketing opportunities

    International Nuclear Information System (INIS)

    Falconnet, P.G.

    1988-01-01

    The rare earths (RE) market is relatively small. The total production during 1968 was only 10000 tons (REO) which rose to 27000 tons (REO) during 1985. The three major areas of application, which are volume market for ceric rare earths are catalysts, glass ceramics and metallurgy. Among the other uses of rare earths, the permanent magnets, lamp phosphors and fine ceramics have registered significant growth in RE consumption. Monazite and bastnasite are the main natural source for rare earths and processing of these for one of the rare earths in high demand leads to over production of some others not in demand, thus creating a balance problem. The growth in RE market has always been influenced by the technology shifts and product substitution. For example, the RE consumption during 1974/76 for desulfurization of steel had substantially decreased due to the usage of calcium. Similarly, 1985 had witnessed a drastic cut in the use of REs in fluid cracking due to the introduction of stabilized zeolites which contain less REO. Thus, the overall compound growth rate of demand was only 3.9 % per year during the period 1970-1985. At present, 37 % of the rare earths production goes to the glass/ceramics industry, 33 % for catalyst and 25 % to metallurgy. The price of REs constantly shows a downward trend. This trend coupled with the rapid changes taking place in the various technological fields, demands greater flexibility and high marketing skills from the RE producers. The key factor for future expansion of RE market will be the development of 'high volume' application of ceric rare earths. (author) 2 figs., 8 tabs

  18. The Earth's mantle and geoneutrinos

    International Nuclear Information System (INIS)

    Fiorentini, Giovanni; Fogli, Gian Luigi; Lisi, Eligio; Mantovani, Fabio; Rotunno, Anna Maria; Xhixha, Gerti

    2013-01-01

    The KamLAND and Borexino experiments have observed, each at ∼4σ level, signals of electron antineutrinos produced in the decay chains of thorium and uranium in the Earth's crust and mantle (Th and U geoneutrinos). Various pieces of geochemical and geophysical information allow an estimation of the crustal geoneutrino flux components with relatively small uncertainties. The mantle component may then be inferred by subtracting the estimated crustal flux from the measured total flux. We find that crust-subtracted signals show hints of a residual mantle component, emerging at ∼2.4σ level by combining the KamLAND and Borexino data. The inferred mantle flux, slightly favoring scenarios with relatively high Th and U abundances, within ∼1σ uncertainties is comparable to the predictions from recent mantle models

  19. The radioactive earth

    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)

  20. The Earth's Biosphere

    Science.gov (United States)

    2002-01-01

    In the last five years, scientists have been able to monitor our changing planet in ways never before possible. The Sea-viewing Wide Field-of-View Sensor (SeaWiFS), aboard the OrbView-2 satellite, has given researchers an unprecedented view of the biological engine that drives life on Earth-the countless forms of plants that cover the land and fill the oceans. 'There is no question the Earth is changing. SeaWiFS has enabled us, for the first time, to monitor the biological consequences of that change-to see how the things we do, as well as natural variability, affect the Earth's ability to support life,' said Gene Carl Feldman, SeaWiFS project manager at NASA's Goddard Space Flight Center, Greenbelt, Md. SeaWiFS data, based on continuous daily global observations, have helped scientists make a more accurate assessment of the oceans' role in the global carbon cycle. The data provide a key parameter in a number of ecological and environmental studies as well as global climate-change modeling. The images of the Earth's changing land, ocean and atmosphere from SeaWiFS have documented many previously unrecognized phenomena. The image above shows the global biosphere from June 2002 measured by SeaWiFS. Data in the oceans is chlorophyll concentration, a measure of the amount of phytoplankton (microscopic plants) living in the ocean. On land SeaWiFS measures Normalized Difference Vegetation Index, an indication of the density of plant growth. For more information and images, read: SeaWiFS Sensor Marks Five Years Documenting Earth'S Dynamic Biosphere Image courtesy SeaWiFS project and copyright Orbimage.

  1. Stress: Concepts and applications

    International Nuclear Information System (INIS)

    Nielsen, O.H.; Martin, R.M.

    1984-01-01

    The stress theorem determines the stress from the electronic ground state of any quantum system with arbitrary strains and atomic displacements. We derive this theorem in reciprocal space, within the local-density-functional approximation. The evaluation of stress, force and total energy permits, among other things, the determination of complete stress-strain relations including all microscopic internal strains. We describe results of ab-initio calculations for Si, Ge, and GaAs, giving the equilibrium lattice constant, all linear elastic constants c ij and the internal strain parameter ζ. (orig.)

  2. Nuclear stress test

    Science.gov (United States)

    ... Persantine stress test; Thallium stress test; Stress test - nuclear; Adenosine stress test; Regadenoson stress test; CAD - nuclear stress; Coronary artery disease - nuclear stress; Angina - nuclear ...

  3. MODIFIED TECHNIQUE OF TOTAL LARYNGECTOMY

    Directory of Open Access Journals (Sweden)

    Predrag Spirić

    2010-12-01

    Full Text Available Surgical technique of total laryngectomy is well presented in many surgical textbooks. Essentially, it has remained the same since Gluck an Soerensen in 1922 described all its details. Generally, it stresses the U shape skin incision with releasing laryngeal structures and removing larynx from up to down. Further, pharyngeal reconstruction is performed with different kinds of sutures in two or more layers and is finished with skin suture and suction drainage. One of worst complications following this surgery is pharyngocutaneous fistula (PF. Modifications proposed in this this article suggests vertical skin incision with larynx removal from below upwards. In pharyngeal reconstruction we used the running locked suture in submucosal plan with „tobacco sac“ at the end on the tongue base instead of traditional T shaped suture. Suction drains were not used.The aim of study was to present the modified surgical technique of total laryingectomy and its impact on hospital stay duration and pharyngocutanous fistula formation. In this randomized study we analyzed 49 patients operated with modified surgical technique compared to 49 patient operated with traditional surgical technique of total laryngectomy. The modified technique of total laryngectomy was presented. Using modified technique we managed to decrease the PF percentage from previous 20,41% to acceptable 8,16% (p=0,0334. Also, the average hospital stay was shortened from 14,96 to 10,63 days (t =-2.9850; p=0.0358.The modified technique of total laryngectomy is safe, short and efficient surgical intervention which decreases the number of pharyngocutaneos fistulas and shortens the hospital stay.

  4. Total Quality Leadership

    Science.gov (United States)

    1991-01-01

    More than 750 NASA, government, contractor, and academic representatives attended the Seventh Annual NASA/Contractors Conference on Quality and Productivity. The panel presentations and Keynote speeches revolving around the theme of total quality leadership provided a solid base of understanding of the importance, benefits, and principles of total quality management (TQM). The presentations from the conference are summarized.

  5. Genoptraening efter total knaealloplastik

    DEFF Research Database (Denmark)

    Holm, Bente; Kehlet, Henrik

    2009-01-01

    The short- and long-term benefits of post-discharge physiotherapy regimens after total knee arthroplasty are debatable. A national survey including hospitals in Denmark that perform total knee arthroplasty showed a large variability in indication and regimen for post-knee arthroplasty...

  6. Korea Earth Observation Satellite Program

    Science.gov (United States)

    Baek, Myung-Jin; Kim, Zeen-Chul

    via Korea Aerospace Research Institute (KARI) as the prime contractor in the area of Korea earth observation satellite program to enhance Korea's space program development capability. In this paper, Korea's on-going and future earth observation satellite programs are introduced: KOMPSAT- 1 (Korea Multi Purpose Satellite-1), KOMPSAT-2 and Communication, Broadcasting and Meteorological Satellite (CBMS) program. KOMPSAT-1 satellite successfully launched in December 1999 with Taurus launch vehicle. Since launch, KOMPSAT-1 is downlinking images of Korea Peninsular every day. Until now, KOMPSAT-1 has been operated more than 2 and half years without any major hardware malfunction for the mission operation. KOMPSAT-1 payload has 6.6m panchromatic spatial resolution at 685 km on-orbit and the spacecraft bus had NASA TOMS-EP (Total Ozone Mapping Spectrometer-Earth Probe) spacecraft bus heritage designed and built by TRW, U.S.A.KOMPSAT-1 program was international co-development program between KARI and TRW funded by Korean Government. be launched in 2004. Main mission objective is to provide geo-information products based on the multi-spectral high resolution sensor called Multi-Spectral Camera (MSC) which will provide 1m panchromatic and 4m multi-spectral high resolution images. ELOP of Israel is the prime contractor of the MSC payload system and KARI is the total system prime contractor including spacecraft bus development and ground segment. KARI also has the contract with Astrium of Europe for the purpose of technical consultation and hardware procurement. Based on the experience throughout KOMPSAT-1 and KOMPSAT-2 space system development, Korea is expecting to establish the infrastructure of developing satellite system. Currently, KOMPSAT-2 program is in the critical design stage. are scheduled to launch in 2008 and in 2014, respectively. The mission of CBMS consists of two areas. One is of space technology test for the communications mission, and the other is of a real

  7. Physics and Chemistry of Earth Materials

    Science.gov (United States)

    Navrotsky, Alexandra

    1994-11-01

    Stressing the fundamental solid state behavior of minerals, and emphasizing both theory and experiment, this text surveys the physics and chemistry of earth materials. The author begins with a systematic tour of crystal chemistry of both simple and complex structures (with completely new structural drawings) and discusses how to obtain structural and thermodynamic information experimentally. Dr. Navrotsky also reviews the quantitative concepts of chemical bonding--band theory, molecular orbit and ionic models. She then covers physical properties and relates microscopic features to macroscopic thermodynamic behavior and treats high pressure phase transitions, amorphous materials and solid state reactions. The author concludes with a look at the interface between mineral physics and materials science. Highly illustrated throughout, this book fills the gap between undergraduate texts and specialized review volumes and is appropriate for students and researchers in earth science and materials science.

  8. Axial focusing of energy from a hypervelocity impact on earth

    Energy Technology Data Exchange (ETDEWEB)

    Boslough, M.B.; Chael, E.P.; Trucano, T.G.; Crawford, D.A.

    1994-12-01

    We have performed computational simulations to determine how energy from a large hypervelocity impact on the Earth`s surface would couple to its interior. Because of the first-order axial symmetry of both the impact energy source and the stress-wave velocity structure of the Earth, a disproportionate amount of energy is dissipated along the axis defined by the impact point and its antipode (point opposite the impact). For a symmetric and homogeneous Earth model, all the impact energy that is radiated as seismic waves into the Earth at a given takeoff angle (ray parameter), independent of azimuthal direction, is refocused (minus attenuation) on the axis of symmetry, regardless of the number of reflections and refractions it has experienced. Material on or near the axis of symmetry experiences more strain cycles with much greater amplitude than elsewhere, and therefore experiences more irreversible heating. The focusing is most intense in the upper mantle, within the asthenosphere, where seismic energy is most effectively converted to heat. For a sufficiently energetic impact, this mechanism might generate enough local heating to create an isostatic instability leading to uplift, possibly resulting in rifting, volcanism, or other rearrangement of the interior dynamics of the planet. These simulations demonstrate how hypervelocity impact energy can be transported to the Earth`s interior, supporting the possibility of a causal link between large impacts on Earth and major internally-driven geophysical processes.

  9. Visualizing Earth Materials

    Science.gov (United States)

    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

  10. Towards earth AntineutRino TomograpHy (EARTH)

    NARCIS (Netherlands)

    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.

  11. 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 ...

  12. Raising awareness for research on earth walls, and earth scientific aspects

    Science.gov (United States)

    van den Ancker, Hanneke; Jungerius, Pieter Dirk; Baas, Henk; Groenewoudt, Bert; Peen, Charlotte

    2013-04-01

    important for earth wall maintenance. A reconnaissance study of earth science aspects of earth walls in Ede The poster further presents a reconnaissance study in the municipality Ede describing differences in morphology, geology and soil profile development. E.g. totally black plaggen A-like horizons occur over 1 m thick, as well as differences in brown B-horizons from 0 cm, 2-3 cm to 15-20 cm. Inferred from cultural data, 2-3 cm B-horizons have an age of about two - three hundred years. Reference Henk Baas, Bert Groenwoudt, Pim Jungerius, Hans Renes (eds.), 2012. Tot hier toe en niet verder - historische wallen in het Nederlandse landschap., RCE - Cultural Heritage Agency of the Netherlands, Amersfoort (includes English summaries)

  13. Laparoscopic total pancreatectomy

    Science.gov (United States)

    Wang, Xin; Li, Yongbin; Cai, Yunqiang; Liu, Xubao; Peng, Bing

    2017-01-01

    Abstract Rationale: Laparoscopic total pancreatectomy is a complicated surgical procedure and rarely been reported. This study was conducted to investigate the safety and feasibility of laparoscopic total pancreatectomy. Patients and Methods: Three patients underwent laparoscopic total pancreatectomy between May 2014 and August 2015. We reviewed their general demographic data, perioperative details, and short-term outcomes. General morbidity was assessed using Clavien–Dindo classification and delayed gastric emptying (DGE) was evaluated by International Study Group of Pancreatic Surgery (ISGPS) definition. Diagnosis and Outcomes: The indications for laparoscopic total pancreatectomy were intraductal papillary mucinous neoplasm (IPMN) (n = 2) and pancreatic neuroendocrine tumor (PNET) (n = 1). All patients underwent laparoscopic pylorus and spleen-preserving total pancreatectomy, the mean operative time was 490 minutes (range 450–540 minutes), the mean estimated blood loss was 266 mL (range 100–400 minutes); 2 patients suffered from postoperative complication. All the patients recovered uneventfully with conservative treatment and discharged with a mean hospital stay 18 days (range 8–24 days). The short-term (from 108 to 600 days) follow up demonstrated 3 patients had normal and consistent glycated hemoglobin (HbA1c) level with acceptable quality of life. Lessons: Laparoscopic total pancreatectomy is feasible and safe in selected patients and pylorus and spleen preserving technique should be considered. Further prospective randomized studies are needed to obtain a comprehensive understanding the role of laparoscopic technique in total pancreatectomy. PMID:28099344

  14. Estonian total ozone climatology

    Directory of Open Access Journals (Sweden)

    K. Eerme

    Full Text Available The climatological characteristics of total ozone over Estonia based on the Total Ozone Mapping Spectrometer (TOMS data are discussed. The mean annual cycle during 1979–2000 for the site at 58.3° N and 26.5° E is compiled. The available ground-level data interpolated before TOMS, have been used for trend detection. During the last two decades, the quasi-biennial oscillation (QBO corrected systematic decrease of total ozone from February–April was 3 ± 2.6% per decade. Before 1980, a spring decrease was not detectable. No decreasing trend was found in either the late autumn ozone minimum or in the summer total ozone. The QBO related signal in the spring total ozone has an amplitude of ± 20 DU and phase lag of 20 months. Between 1987–1992, the lagged covariance between the Singapore wind and the studied total ozone was weak. The spring (April–May and summer (June–August total ozone have the best correlation (coefficient 0.7 in the yearly cycle. The correlation between the May and August total ozone is higher than the one between the other summer months. Seasonal power spectra of the total ozone variance show preferred periods with an over 95% significance level. Since 1986, during the winter/spring, the contribution period of 32 days prevails instead of the earlier dominating 26 days. The spectral densities of the periods from 4 days to 2 weeks exhibit high interannual variability.

    Key words. Atmospheric composition and structure (middle atmosphere – composition and chemistry; volcanic effects – Meteorology and atmospheric dynamics (climatology

  15. Adapting Total Quality Management (TQM) to Government.

    Science.gov (United States)

    Swiss, James E.

    1992-01-01

    Total quality management will not work well in government agencies because of stress on products, not services; on well-defined consumer groups; on inputs/processes, not results; and on preoccupation with quality. An effective revised version emphasizes client feedback, performance monitoring, continuous improvement, and worker participation. (SK)

  16. Total photon absorption

    International Nuclear Information System (INIS)

    Carlos, P.

    1985-06-01

    The present discussion is limited to a presentation of the most recent total photonuclear absorption experiments performed with real photons at intermediate energy, and more precisely in the region of nucleon resonances. The main sources of real photons are briefly reviewed and the experimental procedures used for total photonuclear absorption cross section measurements. The main results obtained below 140 MeV photon energy as well as above 2 GeV are recalled. The experimental study of total photonuclear absorption in the nuclear resonance region (140 MeV< E<2 GeV) is still at its beginning and some results are presented

  17. [Total artificial heart].

    Science.gov (United States)

    Antretter, H; Dumfarth, J; Höfer, D

    2015-09-01

    To date the CardioWest™ total artificial heart is the only clinically available implantable biventricular mechanical replacement for irreversible cardiac failure. This article presents the indications, contraindications, implantation procedere and postoperative treatment. In addition to a overview of the applications of the total artificial heart this article gives a brief presentation of the two patients treated in our department with the CardioWest™. The clinical course, postoperative rehabilitation, device-related complications and control mechanisms are presented. The total artificial heart is a reliable implant for treating critically ill patients with irreversible cardiogenic shock. A bridge to transplantation is feasible with excellent results.

  18. Physics of the Earth

    Science.gov (United States)

    Stacey, Frank D.; Davis, Paul M.

    he fourth edition of Physics of the Earth maintains the original philosophy of this classic graduate textbook on fundamental solid earth geophysics, while being completely revised, updated, and restructured into a more modular format to make individual topics even more accessible. Building on the success of previous editions, which have served generations of students and researchers for nearly forty years, this new edition will be an invaluable resource for graduate students looking for the necessary physical and mathematical foundations to embark on their own research careers in geophysics. Several completely new chapters have been added and a series of appendices, presenting fundamental data and advanced mathematical concepts, and an extensive reference list, are provided as tools to aid readers wishing to pursue topics beyond the level of the book. Over 140 student exercises of varying levels of difficulty are also included, and full solutions are available online at www.cambridge.org/9780521873628.

  19. Alkaline earth metals

    International Nuclear Information System (INIS)

    Brown, Paul L.; Ekberg, Christian

    2016-01-01

    The beryllium ion has a relatively small ionic radius. As a consequence of this small size, its hydrolysis reactions begin to occur at a relatively low pH. To determine the stability and solubility constants, however, the Gibbs energy of the beryllium ion is required. In aqueous solution calcium, like the other alkaline earth metals, only exists as a divalent cation. The size of the alkaline earth cations increases with increasing atomic number, and the calcium ion is bigger than the magnesium ion. The hydrolysis of barium(II) is weaker than that of strontium(II) and also occurs in quite alkaline pH solutions, and similarly, only the species barium hydroxide has been detected. There is only a single experimental study on the hydrolysis of radium. As with the stability constant trend, it would be expected that the enthalpy of radium would be lower than that of barium due to the larger ionic radius.

  20. Heat-pipe Earth.

    Science.gov (United States)

    Moore, William B; Webb, A Alexander G

    2013-09-26

    The heat transport and lithospheric dynamics of early Earth are currently explained by plate tectonic and vertical tectonic models, but these do not offer a global synthesis consistent with the geologic record. Here we use numerical simulations and comparison with the geologic record to explore a heat-pipe model in which volcanism dominates surface heat transport. These simulations indicate that a cold and thick lithosphere developed as a result of frequent volcanic eruptions that advected surface materials downwards. Declining heat sources over time led to an abrupt transition to plate tectonics. Consistent with model predictions, the geologic record shows rapid volcanic resurfacing, contractional deformation, a low geothermal gradient across the bulk of the lithosphere and a rapid decrease in heat-pipe volcanism after initiation of plate tectonics. The heat-pipe Earth model therefore offers a coherent geodynamic framework in which to explore the evolution of our planet before the onset of plate tectonics.

  1. The Nimbus satellites - Pioneering earth observers

    Science.gov (United States)

    White, Carolynne

    1990-01-01

    The many scientific achievements of the Nimbus series of seven satellites for low-altitude atmospheric research and global weather surveillance are reviewed. The series provides information on fishery resources, weather modeling, atmospheric pollution monitoring, earth's radiation budget, ozone monitoring, ocean dynamics, and the effects of cloudiness. Data produced by the forty-eight instruments and sensors flown on the satellites are applied in the fields of oceanography, hydrology, geology, geomorphology, geography, cartography, agriculture and meteorology. The instruments include the Coastal Zone Color Scanner (which depicts phytoplankton concentrations in coastal areas), the Scanning Multichannel Microwave Radiometer (which measures sea-surface temperatures and sea-surface wind-speed), and the Total Ozone Mapping Spectrometer (which provides information on total amounts of ozone in the earth's atmosphere).

  2. Earth before life

    OpenAIRE

    Marzban, Caren; Viswanathan, Raju; Yurtsever, Ulvi

    2014-01-01

    Background 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. Results 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 i...

  3. Electromagnetic compatibility and earths

    International Nuclear Information System (INIS)

    Duque Henao, Alan; Casas Ospina, Favio

    2001-01-01

    It is such the increment of applications of electric and electronic equipment in the modern companies that the lack of control of the electromagnetic perturbations, brings, get big losses and difficulties in the normal operations. The paper contribute to ago with base in the challenges that day-by-day are confronting, where the settings to earth, to be the foundation of the electric building, are fundamental for a good coexistence among the different equipment s

  4. Earth-ionosphere cavity

    International Nuclear Information System (INIS)

    Tran, A.; Polk, C.

    1976-01-01

    To analyze ELF wave propagation in the earth-ionosphere cavity, a flat earth approximation may be derived from the exact equations, which are applicable to the spherical cavity, by introducing a second-order or Debye approximation for the spherical Hankel functions. In the frequency range 3 to 30 Hz, however, the assumed conditions for the Debye approximation are not satisfied. For this reason an exact evaluation of the spherical Hankel functions is used to study the effects of the flat earth approximation on various propagation and resonance parameters. By comparing the resonance equation for a spherical cavity with its flat earth counterpart and by assuming that the surface impedance Z/sub i/ at the upper cavity boundary is known, the relation between the eigenvalue ν and S/sub v/, the sine of the complex angle of incidence at the lower ionosphere boundary, is established as ν(ν + 1) = (kaS/sub v/) 2 . It is also shown that the approximation ν(ν + 1) approximately equals (ν + 1/2) 2 which was used by some authors is not adequate below 30 Hz. Numerical results for both spherical and planar stratification show that (1) planar stratification is adequate for the computation of the lowest three ELF resonance frequencies to within 0.1 Hz; (2) planar stratification will lead to errors in cavity Q and wave attenuation which increase with frequency; (3) computation of resonance frequencies to within 0.1 Hz requires the extension of the lower boundary of the ionosphere to a height where the ratio of conduction current to displacement current, (sigma/ωepsilon 0 ), is less than 0.3; (4) atmospheric conductivity should be considered down to ground level in computing cavity Q and wave attenuation

  5. Superhydrophobic diatomaceous earth

    Science.gov (United States)

    Simpson, John T [Clinton, TN; D& #x27; Urso, Brian R [Clinton, TN

    2012-07-10

    A superhydrophobic powder is prepared by coating diatomaceous earth (DE) with a hydrophobic coating on the particle surface such that the coating conforms to the topography of the DE particles. The hydrophobic coating can be a self assembly monolayer of a perfluorinated silane coupling agent. The DE is preferably natural-grade DE where organic impurities have been removed. The superhydrophobic powder can be applied as a suspension in a binder solution to a substrate to produce a superhydrophobic surface on the substrate.

  6. Total 2004 results

    International Nuclear Information System (INIS)

    2005-02-01

    This document presents the 2004 results of Total Group: consolidated account, special items, number of shares, market environment, adjustment for amortization of Sanofi-Aventis merger-related intangibles, 4. quarter 2004 results (operating and net incomes, cash flow), upstream (results, production, reserves, recent highlights), downstream (results, refinery throughput, recent highlights), chemicals (results, recent highlights), Total's full year 2004 results (operating and net income, cash flow), 2005 sensitivities, Total SA parent company accounts and proposed dividend, adoption of IFRS accounting, summary and outlook, main operating information by segment for the 4. quarter and full year 2004: upstream (combined liquids and gas production by region, liquids production by region, gas production by region), downstream (refined product sales by region, chemicals), Total financial statements: consolidated statement of income, consolidated balance sheet (assets, liabilities and shareholder's equity), consolidated statements of cash flows, business segments information. (J.S.)

  7. Total synthesis of ciguatoxin.

    Science.gov (United States)

    Hamajima, Akinari; Isobe, Minoru

    2009-01-01

    Something fishy: Ciguatoxin (see structure) is one of the principal toxins involved in ciguatera poisoning and the target of a total synthesis involving the coupling of three segments. The key transformations in this synthesis feature acetylene-dicobalthexacarbonyl complexation.

  8. Total 2004 results

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-02-01

    This document presents the 2004 results of Total Group: consolidated account, special items, number of shares, market environment, adjustment for amortization of Sanofi-Aventis merger-related intangibles, 4. quarter 2004 results (operating and net incomes, cash flow), upstream (results, production, reserves, recent highlights), downstream (results, refinery throughput, recent highlights), chemicals (results, recent highlights), Total's full year 2004 results (operating and net income, cash flow), 2005 sensitivities, Total SA parent company accounts and proposed dividend, adoption of IFRS accounting, summary and outlook, main operating information by segment for the 4. quarter and full year 2004: upstream (combined liquids and gas production by region, liquids production by region, gas production by region), downstream (refined product sales by region, chemicals), Total financial statements: consolidated statement of income, consolidated balance sheet (assets, liabilities and shareholder's equity), consolidated statements of cash flows, business segments information. (J.S.)

  9. Genoptraening efter total knaealloplastik

    DEFF Research Database (Denmark)

    Holm, Bente; Kehlet, Henrik

    2009-01-01

    The short- and long-term benefits of post-discharge physiotherapy regimens after total knee arthroplasty are debatable. A national survey including hospitals in Denmark that perform total knee arthroplasty showed a large variability in indication and regimen for post-knee arthroplasty rehabilitat......The short- and long-term benefits of post-discharge physiotherapy regimens after total knee arthroplasty are debatable. A national survey including hospitals in Denmark that perform total knee arthroplasty showed a large variability in indication and regimen for post-knee arthroplasty...... rehabilitation. Since hospital stay duration has decreased considerably, the need for post-discharge physiotherapy may also have changed. Thus, the indication for and types of rehabilitation programmes need to be studied within the context of fast-track knee arthroplasty....

  10. Genoptraening efter total knaealloplastik

    DEFF Research Database (Denmark)

    Holm, Bente; Kehlet, Henrik

    2009-01-01

    The short- and long-term benefits of post-discharge physiotherapy regimens after total knee arthroplasty are debatable. A national survey including hospitals in Denmark that perform total knee arthroplasty showed a large variability in indication and regimen for post-knee arthroplasty rehabilitat......The short- and long-term benefits of post-discharge physiotherapy regimens after total knee arthroplasty are debatable. A national survey including hospitals in Denmark that perform total knee arthroplasty showed a large variability in indication and regimen for post-knee arthroplasty...... rehabilitation. Since hospital stay duration has decreased considerably, the need for post-discharge physiotherapy may also have changed. Thus, the indication for and types of rehabilitation programmes need to be studied within the context of fast-track knee arthroplasty. Udgivelsesdato: 2009-Feb-23...

  11. Sun, Earth and Sky

    CERN Document Server

    Lang, Kenneth R

    2006-01-01

    This Second Edition of Sun, Earth and Sky updates the popular text by providing comprehensive accounts of the most recent discoveries made by five modern solar spacecraft during the past decade. Their instruments have used sound waves to peer deep into the Sun’s inner regions and measure the temperature of its central nuclear reactor, and extended our gaze far from the visible Sun to record energetic outbursts that threaten Earth. Breakthrough observations with the underground Sudbury Neutrino Observatory are also included, which explain the new physics of ghostly neutrinos and solve the problematic mismatch between the predicted and observed amounts of solar neutrinos. This new edition of Sun, Earth and Sky also describes our recent understanding of how the Sun’s outer atmosphere is heated to a million degrees, and just where the Sun’s continuous winds come from. As humans we are more intimately linked with our life-sustaining Sun than with any other astronomical object, and the new edition therefore p...

  12. Characterising Super-Earths

    Directory of Open Access Journals (Sweden)

    Valencia D.

    2011-02-01

    Full Text Available The era of Super-Earths has formally begun with the detection of transiting low-mass exoplanets CoRoT-7b and GJ 1214b. In the path of characterising super-Earths, the first step is to infer their composition. While the discovery data for CoRoT-7b, in combination with the high atmospheric mass loss rate inferred from the high insolation, suggested that it was a rocky planet, the new proposed mass values have widened the possibilities. The combined mass range 1−10 M⊕ allows for a volatile-rich (and requires it if the mass is less than 4 M⊕ , an Earth-like or a super-Mercury-like composition. In contrast, the radius of GJ 1214b is too large to admit a solid composition, thus it necessarily to have a substantial gas layer. Some evidence suggests that within this gas layer H/He is a small but non-negligible component. These two planets are the first of many transiting low-mass exoplanets expected to be detected and they exemplify the limitations faced when inferring composition, which come from the degenerate character of the problem and the large error bars in the data.

  13. Afganistan and rare earths

    Directory of Open Access Journals (Sweden)

    Emilian M. Dobrescu

    2013-05-01

    Full Text Available On our planet, over a quarter of new technologies for the economic production of industrial goods, are using rare earths, which are also called critical minerals and industries that rely on these precious items being worth of an estimated nearly five trillion dollars, or 5 percent of world gross domestic product. In the near future, competition will increase for the control of rare earth minerals embedded in high-tech products. Rare minerals are in the twenty-first century what oil accounted for in the twentieth century and coal in the nineteenth century: the engine of a new industrial revolution. Future energy will be produced increasingly by more sophisticated technological equipment based not just on steel and concrete, but incorporating significant quantities of metals and rare earths. Widespread application of these technologies will result in an exponential increase in demand for such minerals, and what is worrying is that minerals of this type are almost nowhere to be found in Europe and in other industrialized countries in the world, such as U.S. and Japan, but only in some Asian countries, like China and Afghanistan.

  14. Supravaginal eller total hysterektomi?

    DEFF Research Database (Denmark)

    Edvardsen, L; Madsen, E M

    1994-01-01

    There has been a decline in the rate of hysterectomies in Denmark in general over the last thirteen years, together with a rise in the number of supravaginal operations over the last two years. The literature concerning the relative merits of the supravaginal and the total abdominal operation is ...... indicate a reduced frequency of orgasm after the total hysterectomy compared with the supravaginal operation. When there are technical problems peroperatively with an increased urologic risk the supravaginal operation is recommended....

  15. Total lymphoid irradiation

    International Nuclear Information System (INIS)

    Sutherland, D.E.; Ferguson, R.M.; Simmons, R.L.; Kim, T.H.; Slavin, S.; Najarian, J.S.

    1983-01-01

    Total lymphoid irradiation by itself can produce sufficient immunosuppression to prolong the survival of a variety of organ allografts in experimental animals. The degree of prolongation is dose-dependent and is limited by the toxicity that occurs with higher doses. Total lymphoid irradiation is more effective before transplantation than after, but when used after transplantation can be combined with pharmacologic immunosuppression to achieve a positive effect. In some animal models, total lymphoid irradiation induces an environment in which fully allogeneic bone marrow will engraft and induce permanent chimerism in the recipients who are then tolerant to organ allografts from the donor strain. If total lymphoid irradiation is ever to have clinical applicability on a large scale, it would seem that it would have to be under circumstances in which tolerance can be induced. However, in some animal models graft-versus-host disease occurs following bone marrow transplantation, and methods to obviate its occurrence probably will be needed if this approach is to be applied clinically. In recent years, patient and graft survival rates in renal allograft recipients treated with conventional immunosuppression have improved considerably, and thus the impetus to utilize total lymphoid irradiation for its immunosuppressive effect alone is less compelling. The future of total lymphoid irradiation probably lies in devising protocols in which maintenance immunosuppression can be eliminated, or nearly eliminated, altogether. Such protocols are effective in rodents. Whether they can be applied to clinical transplantation remains to be seen

  16. Totally optimal decision rules

    KAUST Repository

    Amin, Talha

    2017-11-22

    Optimality of decision rules (patterns) can be measured in many ways. One of these is referred to as length. Length signifies the number of terms in a decision rule and is optimally minimized. Another, coverage represents the width of a rule’s applicability and generality. As such, it is desirable to maximize coverage. A totally optimal decision rule is a decision rule that has the minimum possible length and the maximum possible coverage. This paper presents a method for determining the presence of totally optimal decision rules for “complete” decision tables (representations of total functions in which different variables can have domains of differing values). Depending on the cardinalities of the domains, we can either guarantee for each tuple of values of the function that totally optimal rules exist for each row of the table (as in the case of total Boolean functions where the cardinalities are equal to 2) or, for each row, we can find a tuple of values of the function for which totally optimal rules do not exist for this row.

  17. Totally optimal decision rules

    KAUST Repository

    Amin, Talha M.; Moshkov, Mikhail

    2017-01-01

    Optimality of decision rules (patterns) can be measured in many ways. One of these is referred to as length. Length signifies the number of terms in a decision rule and is optimally minimized. Another, coverage represents the width of a rule’s applicability and generality. As such, it is desirable to maximize coverage. A totally optimal decision rule is a decision rule that has the minimum possible length and the maximum possible coverage. This paper presents a method for determining the presence of totally optimal decision rules for “complete” decision tables (representations of total functions in which different variables can have domains of differing values). Depending on the cardinalities of the domains, we can either guarantee for each tuple of values of the function that totally optimal rules exist for each row of the table (as in the case of total Boolean functions where the cardinalities are equal to 2) or, for each row, we can find a tuple of values of the function for which totally optimal rules do not exist for this row.

  18. Mineralogy of the rare earth elements

    International Nuclear Information System (INIS)

    Clark, A.M.

    1984-01-01

    This paper contains mineralogic properties of the rare earth elements (REE). Notes are given on total REE abundances, distribution patterns, and modes of occurrence. References are confined as far as possible to papers containing usable REE data. The minerals are grouped alphabetically within each major cationic group. The paper includes an alphabetic table of mineral names, chemical formulas, crystal system and section number. It functions as a handy entrance to the mineralogic and bibliographic paper. (G.J.P.)

  19. Determine Daytime Earth's Radiation Budget from DSCOVR

    Science.gov (United States)

    Su, W.; Thieman, M. M.; Duda, D. P.; Khlopenkov, K. V.; Liang, L.; Sun-Mack, S.; Minnis, P.; SUN, M.

    2017-12-01

    The Deep Space Climate Observatory (DSCOVR) platform provides a unique perspective for remote sensing of the Earth. With the National Institute of Standards and Technology Advanced Radiometer (NISTAR) and the Earth Polychromatic Imaging Camera (EPIC) onboard, it provides full-disk measurements of the broadband shortwave and total radiances reaching the L1 position. Because the satellite orbits around the L1 spot, it continuously observes a nearly full Earth, providing the potential to determine the daytime radiation budget of the globe at the top of the atmosphere. The NISTAR is a single-pixel instrument that measures the broadband radiance from the entire globe, while EPIC is a spectral imager with channels in the UV and visible ranges. The Level 1 NISTAR shortwave radiances are filtered radiances. To determine the daytime TOA shortwave and longwave radiative fluxes, the NISTAR measured shortwave radiances must be unfiltered first. We will describe the algorithm used to un-filter the shortwave radiances. These unfiltered NISTAR radiances are then converted to the full disk shortwave and daytime longwave fluxes, by accounting for the anisotropic characteristics of the Earth-reflected and emitted radiances. These anisotropy factors are determined by using the scene identifications determined from multiple low Earth orbit and geostationary satellites matched into the EPIC field of view. Time series of daytime radiation budget determined from NISTAR will be presented, and methodology of estimating the fluxes from the small unlit crescent of the Earth that comprises part of the field of view will also be described. The daytime shortwave and longwave fluxes from NISTAR will be compared with CERES dataset.

  20. Total volume versus bouts

    DEFF Research Database (Denmark)

    Chinapaw, Mai; Klakk, Heidi; Møller, Niels Christian

    2018-01-01

    BACKGROUND/OBJECTIVES: Examine the prospective relationship of total volume versus bouts of sedentary behaviour (SB) and moderate-to-vigorous physical activity (MVPA) with cardiometabolic risk in children. In addition, the moderating effects of weight status and MVPA were explored. SUBJECTS....../METHODS: Longitudinal study including 454 primary school children (mean age 10.3 years). Total volume and bouts (i.e. ≥10 min consecutive minutes) of MVPA and SB were assessed by accelerometry in Nov 2009/Jan 2010 (T1) and Aug/Oct 2010 (T2). Triglycerides, total cholesterol/HDL cholesterol ratio (TC:HDLC ratio......, with or without mutual adjustments between MVPA and SB. The moderating effects of weight status and MVPA (for SB only) were examined by adding interaction terms. RESULTS: Children engaged daily in about 60 min of total MVPA and 0-15 min/week in MVPA bouts. Mean total sedentary time was around 7 h/day with over 3...

  1. Grid for Earth Science Applications

    Science.gov (United States)

    Petitdidier, Monique; Schwichtenberg, Horst

    2013-04-01

    The civil society at large has addressed to the Earth Science community many strong requirements related in particular to natural and industrial risks, climate changes, new energies. The main critical point is that on one hand the civil society and all public ask for certainties i.e. precise values with small error range as it concerns prediction at short, medium and long term in all domains; on the other hand Science can mainly answer only in terms of probability of occurrence. To improve the answer or/and decrease the uncertainties, (1) new observational networks have been deployed in order to have a better geographical coverage and more accurate measurements have been carried out in key locations and aboard satellites. Following the OECD recommendations on the openness of research and public sector data, more and more data are available for Academic organisation and SMEs; (2) New algorithms and methodologies have been developed to face the huge data processing and assimilation into simulations using new technologies and compute resources. Finally, our total knowledge about the complex Earth system is contained in models and measurements, how we put them together has to be managed cleverly. The technical challenge is to put together databases and computing resources to answer the ES challenges. However all the applications are very intensive computing. Different compute solutions are available and depend on the characteristics of the applications. One of them is Grid especially efficient for independent or embarrassingly parallel jobs related to statistical and parametric studies. Numerous applications in atmospheric chemistry, meteorology, seismology, hydrology, pollution, climate and biodiversity have been deployed successfully on Grid. In order to fulfill requirements of risk management, several prototype applications have been deployed using OGC (Open geospatial Consortium) components with Grid middleware. The Grid has permitted via a huge number of runs to

  2. Total versus subtotal hysterectomy

    DEFF Research Database (Denmark)

    Gimbel, Helga; Zobbe, Vibeke; Andersen, Anna Birthe

    2005-01-01

    The aim of this study was to compare total and subtotal abdominal hysterectomy for benign indications, with regard to urinary incontinence, postoperative complications, quality of life (SF-36), constipation, prolapse, satisfaction with sexual life, and pelvic pain at 1-year postoperative. Eighty...... women chose total and 105 women chose subtotal abdominal hysterectomy. No significant differences were found between the 2 operation methods in any of the outcome measures at 12 months. Fourteen women (15%) from the subtotal abdominal hysterectomy group experienced vaginal bleeding and three women had...

  3. Qualità totale e mobilità totale Total Quality and Total Mobility

    Directory of Open Access Journals (Sweden)

    Giuseppe Trieste

    2010-05-01

    Full Text Available FIABA ONLUS (Italian Fund for Elimination of Architectural Barriers was founded in 2000 with the aim of promoting a culture of equal opportunities and, above all, it has as its main goal to involve public and private institutions to create a really accessible and usable environment for everyone. Total accessibility, Total usability and Total mobility are key indicators to define quality of life within cities. A supportive environment that is free of architectural, cultural and psychological barriers allows everyone to live with ease and universality. In fact, people who access to goods and services in the urban context can use to their advantage time and space, so they can do their activities and can maintain relationships that are deemed significant for their social life. The main aim of urban accessibility is to raise the comfort of space for citizens, eliminating all barriers that discriminate people, and prevent from an equality of opportunity. “FIABA FUND - City of ... for the removal of architectural barriers” is an idea of FIABA that has already affected many regions of Italy as Lazio, Lombardy, Campania, Abruzzi and Calabria. It is a National project which provides for opening a bank account in the cities of referring, in which for the first time, all together, individuals and private and public institutions can make a donation to fund initiatives for the removal of architectural barriers within its own territory for a real and effective total accessibility. Last February the fund was launched in Rome with the aim of achieving a Capital without barriers and a Town European model of accessibility and usability. Urban mobility is a prerequisite to access to goods and services, and to organize activities related to daily life. FIABA promotes the concept of sustainable mobility for all, supported by the European Commission’s White Paper. We need a cultural change in management and organization of public means, which might focus on

  4. Rare Earth Polyoxometalates.

    Science.gov (United States)

    Boskovic, Colette

    2017-09-19

    Longstanding and important applications make use of the chemical and physical properties of both rare earth metals and polyoxometalates of early transition metals. The catalytic, optical, and magnetic features of rare earth metal ions are well-known, as are the reversible multielectron redox and photoredox capabilities of polyoxomolybdates and polyoxotungstates. The combination of rare earth ions and polyoxometalates in discrete molecules and coordination polymers is of interest for the unique combination of chemical and physical properties that can arise. This Account surveys our efforts to synthesize and investigate compounds with rare earth ions and polyoxometalates (RE-POMs), sometimes with carboxylate-based organic coligands. Our general synthetic approach is "bottom-up", which affords well-defined nanoscale molecules, typically in crystalline form and amenable to single-crystal X-ray diffraction for structure determination. Our particular focus is on elucidation of the physical properties conferred by the different structural components with a view to ultimately being able to tune these properties chemically. For this purpose, we employ a variety of spectroscopic, magnetochemical, electrochemical, and scattering techniques in concert with theoretical modeling and computation. Studies of RE-POM single-molecule magnets (SMMs) have utilized magnetic susceptibility, inelastic neutron scattering, and ab initio calculations. These investigations have allowed characterization of the crystal field splitting of the rare earth(III) ions that is responsible for the SMM properties of slow magnetic relaxation and magnetization quantum tunneling. Such SMMs are promising for applications in quantum computing and molecular spintronics. Photophysical measurements of a family of hybrid RE-POMs with organic ligands have afforded insights into sensitization of Tb(III) and Eu(III) emission through both organic and polyoxometalate chromophores in the same molecule. Detailed

  5. Stovetop Earth Pecan Pie

    Science.gov (United States)

    Robin, C. M.

    2005-12-01

    Many fluid mechanical experiments with direct applications to Earth Science are performed with sugary syrups using conceptually straightforward procedures. Corn syrup has indeed proven to be a godsend for those studying convection and related non-linear phenomena. In addition, however, it gives experimentalists a deep physical intuition for the interior workings of hot planets. The basic concepts behind plate tectonics and mantle convection are not difficult; indeed, although they may not be aware of it, most students probably have a basic intuitive understanding of fluid mechanics gained in their daily life. However, the large size and long time scale of geophysical processes may be quite intimidating to young students. Even a simple geophysical experiment requires a complicated array of coolers, heaters and measuring and recording equipment. It is of interest to introduce students to the geodynamical concepts that can be visualized in a high-tech lab using familiar processes and equipment. Using a homemade apparatus and grocery store supplies, I propose using a 'Stove-top Earth pecan pie' to introduce simple geodynamic concepts to middle- and high-school students. The initially cold syrup heats up and the pecans begin to float (continent formation), the syrup begins to convect (mantle convection), and convection slows down after the heat is removed (secular cooling). Even Wilson cycles can be simulated by moving the pan to one side or the other of the stovetop or heating element. The activity formally introduces students to convection and its application to the earth, and makes them think about plate motion, heat transfer, scaling, and experimental procedures. As an added bonus, they can eat their experiments after recess!

  6. Giant Impacts on Earth-Like Worlds

    Science.gov (United States)

    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

  7. Bones of the Earth

    Directory of Open Access Journals (Sweden)

    Jose Miguel Correa

    2014-06-01

    Full Text Available The film Bones of the Earth (Riglin, Cunninham & Correa, 2014 is an experience in collective inquiry and visual creation based on arts-based research. Starting from the meeting of different subjectivities and through dialogue, planning, shooting and editing, an audiovisual text that reconstructs a reflexive process of collective creation is built. A sense of community, on-going inquiry, connections and social commitment inform the creative process. As a result, the video’s nearly five intense minutes are a metaphor for the search for personal meaning, connection with nature and intersubjective positioning in a world that undergoes constant change.

  8. The Solid Earth

    Science.gov (United States)

    Fowler, C. M. R.

    2005-02-01

    The second edition of this acclaimed textbook has been brought fully up-to-date to reflect the latest advances in geophysical research. It is designed for students in introductory geophysics courses who have a general background in the physical sciences, including introductory calculus. New to this edition are a section of color plates and separate sections on the earth's mantle and core. The book also contains an extensive glossary of terms, and includes numerous exercises for which solutions are available to instructors from solutions@cambridge.org. First Edition Hb (1990): 0-521-37025-6 First Edition Pb (1990): 0-521-38590-3

  9. Between Earth and Sky

    DEFF Research Database (Denmark)

    Carter, Adrian

    2009-01-01

    to rescue architecture from the sterile impasse of late-modernism. In his works the basic elements of lived space become present: the earth, the sky and the `between` of human existence." Jørn Utzon's architecture ranges from the modest to the monumental; from the Kingo courtyard houses, the finest...... of form, material and function, motivated by social values. To this essentially regional response, Utzon combines a fascination for the architectural legacies of foreign cultures. These influences include the architecture of the ancient Mayan civilisation, as well as the Islamic world, China and Japan...

  10. Climate in Earth history

    Science.gov (United States)

    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.

  11. Earth's ozone layer

    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

  12. CSF total protein

    Science.gov (United States)

    CSF total protein is a test to determine the amount of protein in your spinal fluid, also called cerebrospinal fluid (CSF). ... The normal protein range varies from lab to lab, but is typically about 15 to 60 milligrams per deciliter (mg/dL) ...

  13. Total body irradiation

    International Nuclear Information System (INIS)

    Novack, D.H.; Kiley, J.P.

    1987-01-01

    The multitude of papers and conferences in recent years on the use of very large megavoltage radiation fields indicates an increased interest in total body, hemibody, and total nodal radiotherapy for various clinical situations. These include high dose total body irradiation (TBI) to destroy the bone marrow and leukemic cells and provide immunosuppression prior to a bone marrow transplant, high dose total lymphoid irradiation (TLI) prior to bone marrow transplantation in severe aplastic anemia, low dose TBI in the treatment of lymphocytic leukemias or lymphomas, and hemibody irradiation (HBI) in the treatment of advanced multiple myeloma. Although accurate provision of a specific dose and the desired degree of dose homogeneity are two of the physicist's major considerations for all radiotherapy techniques, these tasks are even more demanding for large field radiotherapy. Because most large field radiotherapy is done at an extended distance for complex patient geometries, basic dosimetry data measured at the standard distance (isocenter) must be verified or supplemented. This paper discusses some of the special dosimetric problems of large field radiotherapy, with specific examples given of the dosimetry of the TBI program for bone marrow transplant at the authors' hospital

  14. Total design of participation

    DEFF Research Database (Denmark)

    Munch, Anders V.

    2016-01-01

    The idea of design as an art made not only for the people, but also by the people is an old dream going back at least to William Morris. It is, however, reappearing vigoriously in many kinds of design activism and grows out of the visions of a Total Design of society. The ideas of participation b...

  15. Total Quality Management Simplified.

    Science.gov (United States)

    Arias, Pam

    1995-01-01

    Maintains that Total Quality Management (TQM) is one method that helps to monitor and improve the quality of child care. Lists four steps for a child-care center to design and implement its own TQM program. Suggests that quality assurance in child-care settings is an ongoing process, and that TQM programs help in providing consistent, high-quality…

  16. Total Quality Management Seminar.

    Science.gov (United States)

    Massachusetts Career Development Inst., Springfield.

    This booklet is one of six texts from a workplace literacy curriculum designed to assist learners in facing the increased demands of the workplace. The booklet contains seven sections that cover the following topics: (1) meaning of total quality management (TQM); (2) the customer; (3) the organization's culture; (4) comparison of management…

  17. Total photon absorption

    International Nuclear Information System (INIS)

    Carlos, P.

    1985-01-01

    Experimental methods using real photon beams for measurements of total photonuclear absorption cross section σ(Tot : E/sub γ/) are recalled. Most recent σ(Tot : E/sub γ/)results for complex nuclei and in the nucleon resonance region are presented

  18. Total 2004 annual report

    International Nuclear Information System (INIS)

    2004-01-01

    This annual report of the Group Total brings information and economic data on the following topics, for the year 2004: the corporate governance, the corporate social responsibility, the shareholder notebook, the management report, the activities, the upstream (exploration and production) and downstream (refining and marketing) operating, chemicals and other matters. (A.L.B.)

  19. Occupational Stress

    OpenAIRE

    Löblová, Klára

    2011-01-01

    The thesis deals with load, stress and related questions of the working life. Work-related stress brings numerous difficulties not only to affected individuals, but as a result also to organizations. The thesis follows symptoms, impacts, somatic and mental aspects of stress, its types and also types of stressors, which cause this problem. It is concentrated on workload as a specific area of work-related stress, individual resistance to the load, factors of workload and work-related stress and...

  20. Destiny's Earth Observation Window

    Science.gov (United States)

    2002-01-01

    Astronaut Michael J. Bloomfield, STS-110 mission commander, looks through the Earth observation window in the Destiny laboratory aboard the International Space Station (ISS). The STS-110 mission prepared the ISS for future spacewalks by installing and outfitting the S0 (S-zero) truss and the Mobile Transporter. The 43-foot-long S0 Truss, weighing in at 27,000 pounds, was the first of 9 segments that will make up the Station's external framework that will eventually stretch 356 feet (109 meters), or approximately the length of a football field. This central truss segment also includes a flatcar called the Mobile Transporter and rails that will become the first 'space railroad,' which will allow the Station's robotic arm to travel up and down the finished truss for future assembly and maintenance. The completed truss structure will hold solar arrays and radiators to provide power and cooling for additional international research laboratories from Japan and Europe that will be attached to the Station. Milestones of the STS-110 mission included the first time the ISS robotic arm was used to maneuver spacewalkers around the Station and marked the first time all spacewalks were based out of the Station's Quest Airlock. It was also the first Shuttle to use three Block II Main Engines. The Space Shuttle Orbiter Atlantis, STS-110 mission, was launched April 8, 2002 and returned to Earth April 19, 2002.

  1. Mapping Earth's electromagnetic dimensionality

    Science.gov (United States)

    Love, J. J.; Kelbert, A.; Bedrosian, P.

    2017-12-01

    The form of a magnetotelluric impedance tensor, obtained for a given geographic site through simultaneous measurement of geomagnetic and geoelectric field variation, is affected by electrical conductivity structure beneath the measurement site. Building on existing methods for characterizing the symmetry of magnetotelluric impedance tensors, a simple scalar measure is developed for measuring the (frequency dependent) proportion of the impedance tensor that is not just a one-dimensional (1D) function of depth ("non-1D-ness"). These measures are applied to nearly 1000 impedance tensors obtained during magnetotelluric surveys, those for the continental United States and obtained principally through the National Science Foundation's EarthScope project. Across geomagnetic/geoelectric variational periods ranging from 30 s to 3,000 s, corresponding to crustal and upper mantle depths, it is shown that local Earth structure is very often not simply 1D-depth-dependent - often less than 50% of magnetotelluric impedance is 1D. For selected variational frequencies, non-1D-ness is mapped and the relationship between electromagnetic dimensionality and known geological and tectonic structures is discussed. The importance of using realistic surface impedances to accurately evaluate magnetic-storm geoelectric hazards is emphasized.

  2. Is dying the earth?

    International Nuclear Information System (INIS)

    Morales Garzon, Gustavo

    1994-01-01

    December 21 of 1968, on board the capsule Apollo 8, three astronauts, James A. Lovell, Frank Borman and William Anders, went toward what would be the first orbital flight around the moon. That experience like Lovell said, it makes us realize the insignificant that we are in comparison with the vastness of the universe. With the revolution lovelockiane, the life doesn't already consist on a group of organisms only adapted to its atmosphere by a certain action for external laws. The terrestrial environment, instead of being a physical world regulated by own autonomous laws, is part of an evolutionary system that contains the life and that it should to the phenomena vital part of its rules, its mechanisms and components. The alive beings connected to each other and to the atmosphere they manufacture and they maintain of continuous their atmosphere forming an everything at planetary level, according to Ricard Guerrero (1988). The theory of the earth then, he says, it has found their owner Darwin in James lovelock. The document treats topics like the science concept that it is the life, the earth and the contemporary environment

  3. School, Earth and Imagination

    Science.gov (United States)

    Merlini, Anna; Grieco, Giovanni; Oneta, Cristina

    2015-04-01

    Geology needs to be explained and narrated to the people, focusing on the goal of making that big change of mindset that will allow individuals and the entire community to tune into the timing and the ways in which the Earth evolves. In order to achieve these important goals it is necessary to educate children from an early age so that they learn to live an environmentally friendly life. With the project "School, Earth and imagination" we introduce, with a fun and new way, notions and topics in geological and environmental sciences in schools at all levels with the final goal of improving both knowledge and sensibility for these topics into the community. Through this project we start from the children (kindergarten and primary school, ages between 3 and 8 years) because they are the foundation of our society, and without foundations nothing can be built. The "School, Earth and imagination" project wants to give the children a real opportunity to approach reality and in general the surrounding environment, for the first time even before the traditional scholastic experience, with a scientific point of view, experimenting some basic physical concepts like temperature, weight, hardness and so on directly through their body. The project is structured and developed in modules that provide a high flexibility in order to meet needs and requirements of different schools in different situations. Each module is part of the journey of Mariolino, a character that represents a very curious child who introduces basic concepts associating them to geological processes. The Journey of Mariolino, as each module, follows an insistent scheme that starts from the presentation of the problem, follows with its discussion through direct questions and ends with experimentation of the hypotheses that children have proposed to validate the solution of the problem. Each module is independent and never ends without giving children a solution and is always structured with a practical activity

  4. Total 2003 Results

    International Nuclear Information System (INIS)

    2003-01-01

    This document presents the 2003 results of Total Group: consolidated account, special items, number of shares, market environment, 4. quarter 2003 results, full year 2003 results, upstream (key figures, proved reserves), downstream key figures, chemicals key figures, parent company accounts and proposed dividends, 2004 sensitivities, summary and outlook, operating information by segment for the 4. quarter and full year 2003: upstream (combined liquids and gas production by region, liquids production by region, gas production by region), downstream (refinery throughput by region, refined product sales by region, chemicals), impact of allocating contribution of Cepsa to net operating income by business segment: equity in income (loss) and affiliates and other items, Total financial statements: consolidated statement of income, consolidated balance sheet (assets, liabilities and shareholder's equity), consolidated statements of cash flows, business segments information. (J.S.)

  5. TOTAL PERFORMANCE SCORECARD

    Directory of Open Access Journals (Sweden)

    Anca ȘERBAN

    2013-06-01

    Full Text Available The purpose of this paper is to present the evolution of the Balanced Scorecard from a measurement instrument to a strategic performance management tool and to highlight the advantages of implementing the Total Performance Scorecard, especially for Human Resource Management. The study has been accomplished using the methodology of bibliographic study and various secondary sources. Implementing the classical Balanced Scorecard indicated over the years, repeatedly failure. It can be indicated that the crucial level is determined by the learning and growth perspective. It has been developed from a human perspective, which focused on staff satisfaction, innovation perspective with focus on future developments. Integrating the Total Performance Scorecard in an overall framework assures the company’s success, by keeping track of the individual goals, the company’s objectives and strategic directions. Like this, individual identity can be linked to corporate brand, individual aspirations to business goals and individual learning objectives to needed organizational capabilities.

  6. Totally parallel multilevel algorithms

    Science.gov (United States)

    Frederickson, Paul O.

    1988-01-01

    Four totally parallel algorithms for the solution of a sparse linear system have common characteristics which become quite apparent when they are implemented on a highly parallel hypercube such as the CM2. These four algorithms are Parallel Superconvergent Multigrid (PSMG) of Frederickson and McBryan, Robust Multigrid (RMG) of Hackbusch, the FFT based Spectral Algorithm, and Parallel Cyclic Reduction. In fact, all four can be formulated as particular cases of the same totally parallel multilevel algorithm, which are referred to as TPMA. In certain cases the spectral radius of TPMA is zero, and it is recognized to be a direct algorithm. In many other cases the spectral radius, although not zero, is small enough that a single iteration per timestep keeps the local error within the required tolerance.

  7. Total space in resolution

    Czech Academy of Sciences Publication Activity Database

    Bonacina, I.; Galesi, N.; Thapen, Neil

    2016-01-01

    Roč. 45, č. 5 (2016), s. 1894-1909 ISSN 0097-5397 R&D Projects: GA ČR GBP202/12/G061 EU Projects: European Commission(XE) 339691 - FEALORA Institutional support: RVO:67985840 Keywords : total space * resolution random CNFs * proof complexity Subject RIV: BA - General Mathematics Impact factor: 1.433, year: 2016 http://epubs.siam.org/doi/10.1137/15M1023269

  8. MFTF TOTAL benchmark

    International Nuclear Information System (INIS)

    Choy, J.H.

    1979-06-01

    A benchmark of the TOTAL data base management system as applied to the Mirror Fusion Test Facility (MFTF) data base was implemented and run in February and March of 1979. The benchmark was run on an Interdata 8/32 and involved the following tasks: (1) data base design, (2) data base generation, (3) data base load, and (4) develop and implement programs to simulate MFTF usage of the data base

  9. Total - annual report 2005

    International Nuclear Information System (INIS)

    2006-01-01

    This annual report presents the activities and results of TOTAL S.A., french society on oil and gas. It deals with statistics, the managers, key information on financial data and risk factors, information on the Company, unresolved Staff Comments, employees, major Shareholders, consolidated statements, markets, security, financial risks, defaults dividend arrearages and delinquencies, controls and procedures, code of ethics and financial statements. (A.L.B.)

  10. Total Absorption Spectroscopy

    International Nuclear Information System (INIS)

    Rubio, B.; Gelletly, W.

    2007-01-01

    The problem of determining the distribution of beta decay strength (B(GT)) as a function of excitation energy in the daughter nucleus is discussed. Total Absorption Spectroscopy is shown to provide a way of determining the B(GT) precisely. A brief history of such measurements and a discussion of the advantages and disadvantages of this technique, is followed by examples of two recent studies using the technique. (authors)

  11. Sobredentadura total superior implantosoportada

    Directory of Open Access Journals (Sweden)

    Luis Orlando Rodríguez García

    2010-06-01

    Full Text Available Se presenta un caso de un paciente desdentado total superior, rehabilitado en la consulta de implantología de la Clínica "Pedro Ortiz" del municipio Habana del Este en Ciudad de La Habana, Cuba, en el año 2009, mediante prótesis sobre implantes osteointegrados, técnica que se ha incorporado a la práctica estomatológica en Cuba como alternativa al tratamiento convencional en los pacientes desdentados totales. Se siguió un protocolo que comprendió una fase quirúrgica, procedimiento con o sin realización de colgajo y carga precoz o inmediata. Se presenta un paciente masculino de 56 años de edad, que acudió a la consulta multidisciplinaria, preocupado, porque se le habían elaborado tres prótesis en los últimos dos años y ninguna reunía los requisitos de retención que él necesitaba para sentirse seguro y cómodo con las mismas. El resultado final fue la satisfacción total del paciente, con el mejoramiento de la calidad estética y funcional.

  12. Comparative stress patterns in cemented total hip arthroplasty

    NARCIS (Netherlands)

    Huiskes, H.W.J.

    1990-01-01

    The wetting of thin oxide films on silicon by water is affected by fixed charge near the outer surface of the oxide. The authors show that existing data can be analysed to give both the depth and concentration of these fixed charges. The precise values indicate depths of a few angstroms and

  13. Nuclear war would cause total destruction

    International Nuclear Information System (INIS)

    Caldicott, H.

    1985-01-01

    In this paper, the author urges everyone to become better informed about the nuclear hazard humanity faces and challenges the reader to take action to ensure human survival on Earth. The author explains what would happen in the event of a nuclear war. Population centers would be smashed flat. Firestorms would rage over millions of acres. People near the center of the blast would die immediately. Those who survived would reenter a totally devastated world, lacking the life-support systems on which the human species depends. Epidemics would be rampant. Only if we abolish nuclear weapons and permanently halt the nuclear power industry can we hope to survive

  14. Intrinsic Evaporative Cooling by Hygroscopic Earth Materials

    Directory of Open Access Journals (Sweden)

    Alexandra R. Rempel

    2016-08-01

    Full Text Available The phase change of water from liquid to vapor is one of the most energy-intensive physical processes in nature, giving it immense potential for cooling. Diverse evaporative cooling strategies have resulted worldwide, including roof ponds and sprinklers, courtyard fountains, wind catchers with qanats, irrigated green roofs, and fan-assisted evaporative coolers. These methods all require water in bulk liquid form. The evaporation of moisture that has been sorbed from the atmosphere by hygroscopic materials is equally energy-intensive, however, yet has not been examined for its cooling potential. In arid and semi-arid climates, hygroscopic earth buildings occur widely and are known to maintain comfortable indoor temperatures, but evaporation of moisture from their walls and roofs has been regarded as unimportant since water scarcity limits irrigation and rainfall; instead, their cool interiors are attributed to well-established mass effects in delaying the transmission of sensible gains. Here, we investigate the cooling accomplished by daily cycles of moisture sorption and evaporation which, requiring only ambient humidity, we designate as “intrinsic” evaporative cooling. Connecting recent soil science to heat and moisture transport studies in building materials, we use soils, adobe, cob, unfired earth bricks, rammed earth, and limestone to reveal the effects of numerous parameters (temperature and relative humidity, material orientation, thickness, moisture retention properties, vapor diffusion resistance, and liquid transport properties on the magnitude of intrinsic evaporative cooling and the stabilization of indoor relative humidity. We further synthesize these effects into concrete design guidance. Together, these results show that earth buildings in diverse climates have significant potential to cool themselves evaporatively through sorption of moisture from humid night air and evaporation during the following day’s heat. This finding

  15. Cosmic rays and Earth's climate

    DEFF Research Database (Denmark)

    Svensmark, Henrik

    2000-01-01

    During the last solar cycle the Earth's cloud cover underwent a modulation in phase with the cosmic ray flux. Assuming that there is a causal relationship between the two, it is expected and found that the Earth's temperature follows more closely decade variations in cosmic ray flux than other...... solar activity parameters. If the relationship is real the state of the Heliosphere affects the Earth's climate....

  16. Rare earth superlattices

    International Nuclear Information System (INIS)

    McMorrow, D.F.

    1997-01-01

    A review is given of recent experiments on the magnetism of rare earth superlattices. Early experiments in this field were concerned mainly with systems formed by combining a magnetic and a non-magnetic element in a superlattice structure. From results gathered on a variety of systems it has been established that the propagation of magnetic order through the non-magnetic spacer can be understood mostly on the basis of an RKKY-like model, where the strength and range of the coupling depends on the details of the conduction electron susceptibility of the spacer. Recent experiments on more complex systems indicate that this model does not provide a complete description. Examples include superlattices where the constituents can either be both magnetic, adopt different crystal structures (Fermi surfaces), or where one of the constituents has a non-magnetic singlet ground state. The results from such systems are presented and discussed in the context of the currently accepted model. (au)

  17. Earth's Magnetic Field

    DEFF Research Database (Denmark)

    This volume provides a comprehensive view on the different sources of the geomagnetic field both in the Earth’s interior and from the field’s interaction with the terrestrial atmosphere and the solar wind. It combines expertise from various relevant areas of geomagnetic and near Earth space...... research with the aim to better characterise the state and dynamics of Earth’s magnetic field. Advances in the exploitation of geomagnetic observations hold a huge potential not only for an improved quantitative description of the field source but also for a better understanding of the underlying processes...... and space observations, and on state-of-the-art empirical models and physics-based simulations. Thus, it provides an in-depth overview over recent achievements, current limitations and challenges, and future opportunities in the field of geomagnetism and space sciences....

  18. Rare earth (3) pivalates

    International Nuclear Information System (INIS)

    Kuz'mina, N.P.; Martynenko, L.I.; Zoan An' Tu; Ch'eu Tkhi Nguet; Troyanov, S.I.; Rykov, A.N.; Korenev, Yu.M.

    1994-01-01

    Depending on synthesis conditions rare earth pivalates can be obtained in the form of either adducts NPiv·HPiv or hydrates MPiv 3 ·mH 2 O. Adducts are the most stable form of pivalates. Heating of adducts result in formation of corresponding MPiv 3 . MPiv 3 ·nHPiv compounds are characterized by IR-spectroscopy and thermal analysis data. Behaviour of MPiv 3 was studied in the regime of vacuum sublemation. Using mass spectroscopy of NdPiv 3 it was shown that gaseous phase above MPiv 3 had complex composition and contained ligomer fragments. X-ray structure analysis of [NdPiv 3 ·3HPiv] was conducted

  19. One Day on Earth

    CERN Multimedia

    2011-01-01

    In collaboration with the CineGlobe Film Festival, the One Day on Earth global film project invites you to share your story of scientific inspiration, scientific endeavors and technological advancement on 11 November 2011 (11.11.11).   Technology in the 21st century continuously inspires us to re-imagine the world. From outer-space to cyberspace, new ideas that we hope will improve the lives of future generations keep us in a state of change. However, these new technologies may alter the nature of our shared existence in ways not yet known. On 11.11.11, we invite you to record the exciting ways that science is a part of your life, together with people around the world who will be documenting their lives on this day of global creation. See www.onedayonearth.org for details on how to participate.

  20. Earth's radiation belts

    International Nuclear Information System (INIS)

    Moslehi Fard, M.

    1984-01-01

    The theory of trapped particles in a magnetic field of approximated dipole is described completely in the first part. Second part contains experimental results. The mechanism of radiation belt source ''albedo neutrons'' and also types of dissipation mechanism about radiation belt is explained. The trapped protons and electrons by radiation belt is discussed and the life-time of trapped particles are presented. Finally the magnetic fields of Moon, Venus, Mars, and Saturn, measured by passengers Mariner 4,10 and pioneer 10,11 are indicated. The experimental and theoretical results for the explanation of trapped plasma around the earth which is looked like two internal and external belt have almost good correspondence

  1. Earth's early biosphere

    Science.gov (United States)

    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.

  2. Entropy Generation Across Earth's Bow Shock

    Science.gov (United States)

    Parks, George K.; McCarthy, Michael; Fu, Suiyan; Lee E. s; Cao, Jinbin; Goldstein, Melvyn L.; Canu, Patrick; Dandouras, Iannis S.; Reme, Henri; Fazakerley, Andrew; hide

    2011-01-01

    Earth's bow shock is a transition layer that causes an irreversible change in the state of plasma that is stationary in time. Theories predict entropy increases across the bow shock but entropy has never been directly measured. Cluster and Double Star plasma experiments measure 3D plasma distributions upstream and downstream of the bow shock that allow calculation of Boltzmann's entropy function H and his famous H-theorem, dH/dt O. We present the first direct measurements of entropy density changes across Earth's bow shock. We will show that this entropy generation may be part of the processes that produce the non-thermal plasma distributions is consistent with a kinetic entropy flux model derived from the collisionless Boltzmann equation, giving strong support that solar wind's total entropy across the bow shock remains unchanged. As far as we know, our results are not explained by any existing shock models and should be of interests to theorists.

  3. Total Synthesis of Hyperforin.

    Science.gov (United States)

    Ting, Chi P; Maimone, Thomas J

    2015-08-26

    A 10-step total synthesis of the polycyclic polyprenylated acylphloroglucinol (PPAP) natural product hyperforin from 2-methylcyclopent-2-en-1-one is reported. This route was enabled by a diketene annulation reaction and an oxidative ring expansion strategy designed to complement the presumed biosynthesis of this complex meroterpene. The described work enables the preparation of a highly substituted bicyclo[3.3.1]nonane-1,3,5-trione motif in only six steps and thus serves as a platform for the construction of easily synthesized, highly diverse PPAPs modifiable at every position.

  4. Total quality is people

    International Nuclear Information System (INIS)

    Vogel, C.E.

    1991-01-01

    Confronted by changing market conditions and increased global competition, in 1983 the Commercial Nuclear Fuel Division (CNFD) of Westinghouse Electric embarked on an ambitious plan to make total quality the centerpiece of its long-term business strategy. Five years later, the division's efforts in making continuous quality improvement a way of life among its more than 2,000 employees gained national recognition when it was named a charter recipient of the Malcolm Baldridge National Quality Award. What CNFD achieved during the 1980s was a cultural transformation, characterized by an empowered work force committed to a common vision. The company's quality program development strategy is described

  5. Total quality accounting

    Directory of Open Access Journals (Sweden)

    Andrijašević Maja

    2008-01-01

    Full Text Available The focus of competitive "battle" shifted from the price towards non-price instruments, above all, towards quality that became the key variable for profitability increase and achievement of better comparative position of a company. Under such conditions, management of a company, which, according to the established and certified system of total quality, strives towards achieving of a better market position, faces the problem of quality cost measurement and determination. Management, above all, cost accounting can help in solving of this problem, but the question is how much of its potential is being used for that purpose.

  6. Total_Aktion

    DEFF Research Database (Denmark)

    Søndergaard, Morten

    2008-01-01

    digitale medier er registreringen og muligheden for at opbevare og håndtere digital data uden begrænsninger. Oplevelse, registrering og bevaring knyttes sammen i en ny museal virkelighed, hvor samlingens særlige dokumentariske karakter og fokus, som er unikt for Museet for Samtidskunst, er i centrum...... at mikse deres personlige drinks. TOTAL_AKTION viser Hørbar#3, som er en videreudvikling af den første version. METASYN af Carl Emil Carlsen: Metadata er centralt for Carl Emil Carlsens projekt, der betragter museets samling som et ”univers” af værker (analoge og digitale), beskrivelser og relationer. I...

  7. Total Logistic Plant Solutions

    Directory of Open Access Journals (Sweden)

    Dusan Dorcak

    2016-02-01

    Full Text Available The Total Logistics Plant Solutions, plant logistics system - TLPS, based on the philosophy of advanced control processes enables complex coordination of business processes and flows and the management and scheduling of production in the appropriate production plans and planning periods. Main attributes of TLPS is to create a comprehensive, multi-level, enterprise logistics information system, with a certain degree of intelligence, which accepts the latest science and research results in the field of production technology and logistics. Logistic model of company understands as a system of mutually transforming flows of materials, energy, information, finance, which is realized by chain activities and operations

  8. Total Factbook 2003

    International Nuclear Information System (INIS)

    2003-01-01

    This report presents the activities and results of the Group Total-Fina-Elf for the year 2003. It brings information and economic data on the following topics: the corporate and business; the upstream activities with the reserves, the costs, standardized measure and changes of discounted future net cash flow,oil and gas acreage, drilling, liquefied natural gas, pipelines; downstream activities with refining and marketing maps, refinery, petroleum products, sales, retail gasoline outlets; chemicals with sales and operating income by sector, major applications, base chemicals and polymers, intermediates and performance polymers. (A.L.B.)

  9. Total 2004 fact book

    International Nuclear Information System (INIS)

    2004-01-01

    This report presents the activities and results of the Group Total-Fina-Elf for the year 2004. It brings information and economic data on the following topics: the corporate and business; the upstream activities with the reserves, the costs, standardized measure and changes of discounted future net cash flow,oil and gas acreage, drilling, liquefied natural gas, pipelines; downstream activities with refining and marketing maps, refinery, petroleum products, sales, retail gasoline outlets; chemicals with sales and operating income by sector, major applications, base chemicals and polymers, intermediates and performance polymers. (A.L.B.)

  10. TOTAL annual report 2003

    International Nuclear Information System (INIS)

    2004-01-01

    This 2003 annual report of the Group Total provides economical results and information of the society on the following topics: keys data, the corporate governance (Directors charter, board of directors, audit committee, nomination and remuneration committee, internal control procedures, compensation of directors and executive officers), the corporate social responsibility (environmental stewardship, the future of energy management, the safety enhancement, the human resources, ethics and local development), the investor relations, the management report, the upstream exploration and production, the downstream refining, marketing, trading and shipping, the chemicals and financial and legal information. (A.L.B.)

  11. Total knee arthroplasty

    DEFF Research Database (Denmark)

    Schrøder, Henrik M.; Petersen, Michael M.

    2016-01-01

    Total knee arthroplasty (TKA) is a successful treatment of the osteoarthritic knee, which has increased dramatically over the last 30 years. The indication is a painful osteoarthritic knee with relevant radiographic findings and failure of conservative measures like painkillers and exercise...... surgeon seems to positively influence the rate of surgical complications and implant survival. The painful TKA knee should be thoroughly evaluated, but not revised except if a relevant indication can be established. The most frequent indications for revision are: aseptic loosening, instability, infection...

  12. The earth and the moon

    CERN Document Server

    Elkins-Tanton, Linda T

    2010-01-01

    The moon is the only body in the solar system outside of the Earth that has been visited by humans. More than 440 pounds of lunar material are brought by NASA and Soviet space missions to Earth for study. The information gleaned about the moon from this relatively small pile of rocks is mind-boggling and stands as the greatest proof that Martian planetary science would be greatly enhanced by returning samples to Earth. Compositional studies of lunar rocks show that the moon and the Earth are made of similar material, and because lunar material has not been reworked through erosion and plate te

  13. The Young and the Stressed

    DEFF Research Database (Denmark)

    Leppink, Eric W.; Odlaug, Brian L.; Lust, Katherine

    2016-01-01

    among college students, are limited. This study examined potential associations between perceived stress, academic achievement, physical/mental health, and impulse control disorders in young adults. A total of 1805 students completed an online survey and were included in the analysis. Responders were...... stress and numerous aspects of mental/physical health in young adults, which could be an important consideration for individuals working with college students.......High levels of stress are common among young adults, particularly those enrolled in college. These degrees of stress have shown numerous deleterious effects across both academic and health variables. Findings regarding the role of stress in the presentation of impulse control disorders, particular...

  14. Total Quality Management in Higher Education: Applying Deming's Fourteen Points.

    Science.gov (United States)

    Masters, Robert J.; Leiker, Linda

    1992-01-01

    This article presents guidelines to aid administrators of institutions of higher education in applying the 14 principles of Total Quality Management. The principles stress understanding process improvements, handling variation, fostering prediction, and using psychology to capitalize on human resources. (DB)

  15. TOTAL user manual

    Science.gov (United States)

    Johnson, Sally C.; Boerschlein, David P.

    1994-01-01

    Semi-Markov models can be used to analyze the reliability of virtually any fault-tolerant system. However, the process of delineating all of the states and transitions in the model of a complex system can be devastatingly tedious and error-prone. Even with tools such as the Abstract Semi-Markov Specification Interface to the SURE Tool (ASSIST), the user must describe a system by specifying the rules governing the behavior of the system in order to generate the model. With the Table Oriented Translator to the ASSIST Language (TOTAL), the user can specify the components of a typical system and their attributes in the form of a table. The conditions that lead to system failure are also listed in a tabular form. The user can also abstractly specify dependencies with causes and effects. The level of information required is appropriate for system designers with little or no background in the details of reliability calculations. A menu-driven interface guides the user through the system description process, and the program updates the tables as new information is entered. The TOTAL program automatically generates an ASSIST input description to match the system description.

  16. POPULATION Total Population NMHD 2000

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — The 2006 Second Edition TIGER/Line files are an extract of selected geographic and cartographic information from the Census TIGER database. The geographic coverage...

  17. POPULATION Total Population BGs 2000

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — TIGER, TIGER/Line, and Census TIGER are registered trademarks of the Bureau of the Census. The Redistricting Census 2000 TIGER/Line files are an extract of selected...

  18. POPULATION Total Population COS 2000

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — TIGER, TIGER/Line, and Census TIGER are registered trademarks of the Bureau of the Census. The Redistricting Census 2000 TIGER/Line files are an extract of selected...

  19. POPULATION Total Population CTs 2000

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — TIGER, TIGER/Line, and Census TIGER are registered trademarks of the Bureau of the Census. The Redistricting Census 2000 TIGER/Line files are an extract of selected...

  20. POPULATION Total Population NMSD 2000

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — The 2006 Second Edition TIGER/Line files are an extract of selected geographic and cartographic information from the Census TIGER database. The geographic coverage...

  1. Cold Stress

    Science.gov (United States)

    ... Publications and Products Programs Contact NIOSH NIOSH COLD STRESS Recommend on Facebook Tweet Share Compartir Workers who ... cold environments may be at risk of cold stress. Extreme cold weather is a dangerous situation that ...

  2. Heat Stress

    Science.gov (United States)

    ... Publications and Products Programs Contact NIOSH NIOSH HEAT STRESS Recommend on Facebook Tweet Share Compartir OSHA-NIOSH ... hot environments may be at risk of heat stress. Exposure to extreme heat can result in occupational ...

  3. China's rare-earth industry

    Science.gov (United States)

    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.

  4. 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

  5. Total process surveillance: (TOPS)

    International Nuclear Information System (INIS)

    Millar, J.H.P.

    1992-01-01

    A Total Process Surveillance system is under development which can provide, in real-time, additional process information from a limited number of raw measurement signals. This is achieved by using a robust model based observer to generate estimates of the process' internal states. The observer utilises the analytical reduncancy among a diverse range of transducers and can thus accommodate off-normal conditions which lead to transducer loss or damage. The modular hierarchical structure of the system enables the maximum amount of information to be assimilated from the available instrument signals no matter how diverse. This structure also constitutes a data reduction path thus reducing operator cognitive overload from a large number of varying, and possibly contradictory, raw plant signals. (orig.)

  6. Total and EDF invest

    International Nuclear Information System (INIS)

    Signoret, St.

    2008-01-01

    So as to prepare the future of their industrial sector,the Total company plans to invest (14 billion Euros in 2008) to increase its production capacities and strengthen in of other activities as the liquefied natural gas and the renewable energies; EDF plans to inject 35 billion Euros over three years to multiply the new projects of power plants (wind turbines, coal in Germany, gas in Great Britain and nuclear power in Flamanville). EDF wants to exploit its knowledge of leader to run more than ten E.P.R.(European pressurized water reactor) in the world before 2020, projects are in examination with China, Great Britain, South Africa and United States. (N.C.)

  7. Total quality at source

    International Nuclear Information System (INIS)

    Chiandone, A.C.

    1990-01-01

    The Total Quality at Source philosophy is based on optimizing the effectiveness of people in achieving ZERO-DEFECT results. In this paper a philosophy of what, I have come to perceive, it takes to get people to perform to the very best of their abilities and thereby achieve the best results they can, is presented. In the examples I shall describe I have played an instrumental role since it has become my belief that any job can always be done better provided that the people doing it can themselves become convinced that they can do better. Clearly there are many ideas on how to do this. The philosophy that I am presenting in this paper is based on my own experience, where I have both participated and observed it being applied; its effectiveness may be judged by the results. (author)

  8. Radiological aspects in a monazite based rare earth production facility

    International Nuclear Information System (INIS)

    Harikumar, M.; Sujata, R.; Chinnaesakki, S.; Tripathi, R.M.; Puranik, V.D.; Nair, N.N.G.

    2011-01-01

    One of the largest reserves of monazite in the world is present in the Indian subcontinent. Monazite ore has around 8-9% thorium oxide and nearly 60% Rare earth oxides. Selective acid extraction is used to separate the composite rare earths. The main radiological hazard arises from the presence of thorium and its daughter products. Monitoring of the radiation field and air activity in the rare earths plant is done routinely to reduce the radiation exposure to plant personnel. The separation of uranium and rare earths from Thorium concentrate separated from Monazite is being done as a part of the THRUST (Thorium Retrieval, Recovery of Uranium and Re-storage of Thorium) project from 2004 at Indian Rare Earths Limited, Udyogamandal. The radiological aspect for this extraction of uranium and rare earths was studied. The general radiation field in the rare earth production plant was 0.3-5.0 μGyh -1 and the average short lived air activity was 46 ± 7 mWL. The long lived air activity arising from 232 Th is very insignificant radiologically. The occupational radiation exposure for the rare earths separation plant is only 6 % of the total dose and the estimated average individual dose is 1.6 mSv per year. Studies were also done to estimate the residual radioactivity in the separated rare earth compounds using gamma spectrometry and the results showed significant presence of 227 Ac arising due to the protactinium fraction in the thorium concentrate. This activity is not detectable in a freshly separated rare earth compound but can buildup with time. (author)

  9. Neuromuscular Stress.

    Science.gov (United States)

    White, Timothy P.; Kern, Marialice

    1994-01-01

    Discusses exercise-induced stress that results from motor unit recruitment, the impact of recruitment on selected systemic support systems, and some of the environmental overlays that affect the degree of physiological stress. Adaptations to sustained changes in physical activity and muscle and myotendinous injury induced by stress are examined.…

  10. Stress Fractures

    Science.gov (United States)

    Stress fractures Overview Stress fractures are tiny cracks in a bone. They're caused by repetitive force, often from overuse — such as repeatedly jumping up and down or running long distances. Stress fractures can also arise from normal use of ...

  11. Axial focusing of energy from a hypervelocity impact on earth

    International Nuclear Information System (INIS)

    Boslough, M.B.; Chael, E.P.; Trucano, T.G.; Crawford, D.A.

    1994-01-01

    We have performed computational simulations to determine how energy from a large hypervelocity impact on the Earth's surface would couple to its interior. Because of the first-order axial symmetry of both the impact energy source and the stress-wave velocity structure of the Earth, a disproportionate amount of energy is dissipated along the axis defined by the impact point and its antipode (point opposite the impact). For a symmetric and homogeneous Earth model, all the impact energy that is radiated as seismic waves into the Earth at a given takeoff angle (ray parameter), independent of azimuthal direction, is refocused (minus attenuation) on the axis of symmetry, regardless of the number of reflections and refractions it has experienced. Material on or near the axis of symmetry experiences more strain cycles with much greater amplitude than elsewhere, and therefore experiences more irreversible heating. The focusing is most intense in the upper mantle, within the asthenosphere, where seismic energy is most effectively converted to heat. For a sufficiently energetic impact, this mechanism might generate enough local heating to create an isostatic instability leading to uplift, possibly resulting in rifting, volcanism, or other rearrangement of the interior dynamics of the planet. These simulations demonstrate how hypervelocity impact energy can be transported to the Earth's interior, supporting the possibility of a causal link between large impacts on Earth and major internally-driven geophysical processes

  12. Next-generation digital earth

    NARCIS (Netherlands)

    Goodchild, M.F.; Guo, H.; Annoni, A.; Bian, L.; Bie, de K.; Campbell, F.; Craglia, M.; Ehlers, M.; Genderen, van J.; Skidmore, A.K.; Wang, C.; Woodgate, P.

    2012-01-01

    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

  13. LIMNOLOGICAL OPTOMETRY: EXAMINING EARTH'S EYE

    Science.gov (United States)

    In Thoreau's Walden, a lake is described as the landscape's most expressive feature and the earth's eye. Collectively, scientists are charged by society to assess, monitor, and remedy maladies of earth's eye in the same way optometrists maintain the health of the human eye. This ...

  14. Melting in super-earths.

    Science.gov (United States)

    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.

  15. 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.

  16. Introductory mathematics for earth scientists

    CERN Document Server

    Yang, Xin-She

    2009-01-01

    Any quantitative work in earth sciences requires mathematical analysis and mathematical methods are essential to the modelling and analysis of the geological, geophysical and environmental processes involved. This book provides an introduction to the fundamental mathematics that all earth scientists need.

  17. Teaching Waves with Google Earth

    Science.gov (United States)

    Logiurato, Fabrizio

    2012-01-01

    Google Earth is a huge source of interesting illustrations of various natural phenomena. It can represent a valuable tool for science education, not only for teaching geography and geology, but also physics. Here we suggest that Google Earth can be used for introducing in an attractive way the physics of waves. (Contains 9 figures.)

  18. Appraisal of ANN and ANFIS for Predicting Vertical Total Electron ...

    African Journals Online (AJOL)

    Positional accuracy in the usage of GPS receiver is one of the major challenges in GPS observations. The propagation of the GPS signals are interfered by free electrons which are the massive particles in the ionosphere region and results in delays in the transmission of signals to the Earth. Therefore, the total electron ...

  19. Precise estimation of total solar radiation on tilted surface

    African Journals Online (AJOL)

    rajeev

    rarely available required for precise sizing of energy systems. The total solar radiation at different orientation and slope is needed to calculate the efficiency of the installed solar energy systems. To calculate clearness index (Kt) used by Gueymard (2000) for estimating solar irradiation H, irradiation at the earth's surface has ...

  20. LIDAR technology developments in support of ESA Earth observation missions

    Science.gov (United States)

    Durand, Yannig; Caron, Jérôme; Hélière, Arnaud; Bézy, Jean-Loup; Meynart, Roland

    2017-11-01

    Critical lidar technology developments have been ongoing at the European Space Agency (ESA) in support of EarthCARE (Earth Clouds, Aerosols, and Radiation Explorer), the 6th Earth Explorer mission, and A-SCOPE (Advanced Space Carbon and Climate Observation of Planet Earth), one of the candidates for the 7th Earth Explorer mission. EarthCARE is embarking an Atmospheric backscatter Lidar (ATLID) while A-SCOPE is based on a Total Column Differential Absorption Lidar. As EarthCARE phase B has just started, the pre-development activities, aiming at validating the technologies used in the flight design and at verifying the overall instrument performance, are almost completed. On the other hand, A-SCOPE pre-phase A has just finished. Therefore technology developments are in progress, addressing critical subsystems or components with the lowest TRL, selected in the proposed instrument concepts. The activities described in this paper span over a broad range, addressing all critical elements of a lidar from the transmitter to the receiver.

  1. Total lymphoid irradiation

    International Nuclear Information System (INIS)

    Anon.

    1980-01-01

    An outline review notes recent work on total lymphoid irradiation (TLI) as a means of preparing patients for grafts and particularly for bone-marrow transplantation. T.L.I. has proved immunosuppressive in rats, mice, dogs, monkeys and baboons; when given before bone-marrow transplantation, engraftment took place without, or with delayed rejection or graft-versus-host disease. Work with mice has indicated that the thymus needs to be included within the irradiation field, since screening of the thymus reduced skin-graft survival from 50 to 18 days, though irradiation of the thymus alone has proved ineffective. A more lasting tolerance has been observed when T.L.I. is followed by an injection of donor bone marrow. 50% of mice treated in this way accepted allogenic skin grafts for more than 100 days, the animals proving to be stable chimeras with 50% of their peripheral blood lymphocytes being of donor origin. Experiments of a similar nature with dogs and baboons were not so successful. (U.K.)

  2. The total artificial heart.

    Science.gov (United States)

    Cook, Jason A; Shah, Keyur B; Quader, Mohammed A; Cooke, Richard H; Kasirajan, Vigneshwar; Rao, Kris K; Smallfield, Melissa C; Tchoukina, Inna; Tang, Daniel G

    2015-12-01

    The total artificial heart (TAH) is a form of mechanical circulatory support in which the patient's native ventricles and valves are explanted and replaced by a pneumatically powered artificial heart. Currently, the TAH is approved for use in end-stage biventricular heart failure as a bridge to heart transplantation. However, with an increasing global burden of cardiovascular disease and congestive heart failure, the number of patients with end-stage heart failure awaiting heart transplantation now far exceeds the number of available hearts. As a result, the use of mechanical circulatory support, including the TAH and left ventricular assist device (LVAD), is growing exponentially. The LVAD is already widely used as destination therapy, and destination therapy for the TAH is under investigation. While most patients requiring mechanical circulatory support are effectively treated with LVADs, there is a subset of patients with concurrent right ventricular failure or major structural barriers to LVAD placement in whom TAH may be more appropriate. The history, indications, surgical implantation, post device management, outcomes, complications, and future direction of the TAH are discussed in this review.

  3. Changes in earth's dipole.

    Science.gov (United States)

    Olson, Peter; Amit, Hagay

    2006-11-01

    The dipole moment of Earth's magnetic field has decreased by nearly 9% over the past 150 years and by about 30% over the past 2,000 years according to archeomagnetic measurements. Here, we explore the causes and the implications of this rapid change. Maps of the geomagnetic field on the core-mantle boundary derived from ground-based and satellite measurements reveal that most of the present episode of dipole moment decrease originates in the southern hemisphere. Weakening and equatorward advection of normal polarity magnetic field by the core flow, combined with proliferation and growth of regions where the magnetic polarity is reversed, are reducing the dipole moment on the core-mantle boundary. Growth of these reversed flux regions has occurred over the past century or longer and is associated with the expansion of the South Atlantic Anomaly, a low-intensity region in the geomagnetic field that presents a radiation hazard at satellite altitudes. We address the speculation that the present episode of dipole moment decrease is a precursor to the next geomagnetic polarity reversal. The paleomagnetic record contains a broad spectrum of dipole moment fluctuations with polarity reversals typically occurring during dipole moment lows. However, the dipole moment is stronger today than its long time average, indicating that polarity reversal is not likely unless the current episode of moment decrease continues for a thousand years or more.

  4. When the earth shudders

    Energy Technology Data Exchange (ETDEWEB)

    Maltese, G.

    The enormous damage that can be caused by earthquakes (500,000 deaths in Tangshan, China, 1976) makes the art and science of earthquake predicting one of the principal objectives of modern geophysics. In this review of the state-of-the-art in earthquake predicting, brief notes are given on several topics: plate tectonics theory, geographic distribution of earthquakes, elastic potential energy storage of rocks, seismic wave typology, comparison of Mercalli and Richter scales, pre-warning signs in nature (strange behaviour of animals, preliminary reduction of seismic wave velocity, variations in local micro-seismicity and physical properties of rocks, etc.), comparison of earthquake energy release models, historical origin of the science of earthquake predicting, implication of fault slip rates and earthquake recurrence models to probabilistic seismic hazard estimates, the time element in prediction making, analysis of examples of correct predictions, pattern recognition instrumentation, earthquake intensity control through fluid injection, correlations between water reservoir level and seismicity, the creation of government programs for the monitoring of the earth's crust and seismic data acquisition, comparison of earthquake prediction and preparedness approaches in Japan and the USA.

  5. Our sustainable Earth

    International Nuclear Information System (INIS)

    Orbach, Raymond L

    2011-01-01

    Recent evidence demonstrates that the Earth has been warming monotonically since 1980. Transient to equilibrium temperature changes take centuries to develop, as oceans are slow to respond to atmospheric temperature changes. Atmospheric CO 2 concentrations, from ice core and observatory measurements, display consistent increases from historical averages, beginning in about 1880, and can be associated with the industrial revolution. The climactic consequences of this human dominated increase in atmospheric CO 2 define a geologic epoch that has been termed the 'Anthropocene.' The issue is whether this is a short term, relatively minor change in global climate, or an extreme deviation that lasts for thousands of years. Eight 'myths' that posit the former are examined in light of known data. The analysis strongly suggests the latter. In order to stabilize global temperatures, sharp reductions in CO 2 emissions are required: an 80% reduction beginning in 2050. Two examples of economically sustainable CO 2 emission reduction demonstrate that technological innovation has the potential to maintain our standard of living while stabilizing global temperatures.

  6. Space sickness on earth

    Science.gov (United States)

    Nooij, S. A. E.; Bos, J. E.; Groen, E. L.; Bles, W.; Ockels, W. J.

    2007-09-01

    During the first days in space, i.e., after a transition from 1G to 0G, more than 50% of the astro- (and cosmonauts) suffer from the Space Adaptation Syndrome (SAS).The symptoms of SAS, like nausea and dizziness, are especially provoked by head movements. Astronauts have mentioned close similarities between the symptoms of SAS and the symptoms they experienced after a 1 hour centrifuge run on Earth, i.e., after a transition from 3G to 1G (denoted by Sickness Induced by Centrifugation, SIC). During several space missions, we related susceptibility to SAS and to SIC in 11 astronauts and found 4 of them being susceptible to both SIC and SAS, and 7 being not susceptible to SIC nor to SAS. This correspondence in susceptibility suggests that SIC and SAS share the same underlying mechanism. To further study this mechanism, several vestibular parameters have been investigated (e.g. postural stability, vestibularly driven eye movements, subjective vertical). We found some striking changes in individual cases that are possibly due to the centrifuge run. However, the variability between subjects generally is very large, making physiological links to SIC and SAS still hard to find.

  7. Study on lowering the specific radioactivity of rare earth chlorides

    International Nuclear Information System (INIS)

    Shinhuor, Y.; Jyuung, J.; Shyuerjung, T.; Xiangping, L.

    1985-01-01

    In this paper, the source of radioactivity in rare earth chlorides and the chemical behaviour of its main radionuclides in metallurgy processing are investigated. It is pointed out that the radioactivity in rare earths comes from the long-life radionuclides in three natural radioactive series. Nine of them (/sup 238/U, /sup 234/U, /sup 230/Th, /sup 226/Ra, /sup 210/Po, /sup 232/Th, /sup 228/Th, /sup 235/U, /sup 231/Pa) are alpha-emitters, three of them (/sup 228/Ra, /sup 227/Ac, /sup 210/Pb) are beta-emitters. Among them alpha-emitters contribute the total specific activity of rare earths directly. The rare earths are easily purified in preferential dissolution, radium elimination, and other processes

  8. Magnetic field of the Earth

    Science.gov (United States)

    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

  9. What if mankind warms the earth

    International Nuclear Information System (INIS)

    Kellogg, W.W.

    1977-01-01

    There are a variety of human activities that are being pursued on such a large scale that they may influence regional and global climate. Virtually all of these activities, including the addition of carbon dioxide and particles to the atmosphere, are expected on theoretical grounds to cause an increase in mean surface temperature in the decades ahead, and by 2000 AD the total warming effect will probably be larger than any of the natural climate fluctuations during the past 1,000 years or more. It is therefore pertinent ot inquire what a warmer earth might be like; and to obtain a first rough answer we turn to our mathematical models of the atmosphere, and also to the conditions that have been deduced for the period about 4,000 to 8,000 years ago when the earth was apparently several degress warmer the now. Atan now. At that time some areas that are now subtropical deserts received more rainfall, and there were other areas in the middle latitudes that were drier. There are several important implications for society if mankind does succeed in warming the earth - and a number of still unanswered questions as well. (orig.) [de

  10. Rankine earth pressure theory considering microstructure of porous materials

    Science.gov (United States)

    Li, Junhu; Xue, Wei; Zhang, Chao; Zhang, Wenchao; Xu, Riqing

    2017-11-01

    Soil as an engineering material has very complex properties, such as non-continuous, non-uniformity and nonlinear mechanical. In a certain extent, macroscopic properties of soil are affected by the changes of the microstructure. And microscopic porosity of soft clay and its influencing factors, the relationship between macro and micro porosity, the average contact area rate and its influencing factors are studied. Some mechanics problems were analyzed by using the relationship between macro-porosity and the average contact area rate. Combining soil lateral stress transfer principle, a calculation theory of earth pressure considering soil contact area was got. The possible reason of the differences between earth pressure and the actual monitoring earth pressure was analyzed by the case.

  11. Laser Prevention of Earth Impact Disasters

    Science.gov (United States)

    Campbell, Jonathan W.; Howell, Joe (Technical Monitor)

    2002-01-01

    Today we are seeing the geological data base constantly expanding as new evidence from past impacts with the Earth are discovered and investigated. It is now commonly believed that a hypervelocity impact occurring approximately 65 million years ago in the Yucatan Peninsula area was the disaster responsible for the extinction of almost 70% of the species of life on Earth including of course the dinosaurs. What is sobering is that we believe now that this was just one of several such disasters and that some of the others caused extinctions to even a greater extent. Preventing collisions with the Earth by hypervelocity asteroids, meteoroids, and comets is the most important problem facing human civilization. While there are many global problems facing our planet including overpopulation, pollution, disease, and deforestation; none of these offer the potential of rapid, total extinction. Rapid is the operative word here in that many of the global problems we face may indeed, if not sufficiently addressed, pose a similar long-term threat. However, with the impact threat, a single, almost unpredictable event could lead to a chain reaction of disasters that would end everything mankind has worked to achieve over the centuries. Our chances of being hit are greater than our chance of winning the lottery. We now believe that while there are only about 2000-earth orbit crossing rocks great than 1 kilometer in diameter, there may be as many as 100,000 rocks in the 100 m size range. The 1 kilometer rocks are difficult to detect and even harder to track. The 100 m class ones are almost impossible to find with today's technology. Can anything be done about this fundamental existence question facing us? The answer is a resounding yes. By using an intelligent combination of Earth and space based sensors coupled with high-energy laser stations in orbit, we can deflect rocks from striking the Earth. This is accomplished by irradiating the surface of the rock with sufficiently intense

  12. Residual stresses

    International Nuclear Information System (INIS)

    Sahotra, I.M.

    2006-01-01

    The principal effect of unloading a material strained into the plastic range is to create a permanent set (plastic deformation), which if restricted somehow, gives rise to a system of self-balancing within the same member or reaction balanced by other members of the structure., known as residual stresses. These stresses stay there as locked-in stresses, in the body or a part of it in the absence of any external loading. Residual stresses are induced during hot-rolling and welding differential cooling, cold-forming and extruding: cold straightening and spot heating, fabrication and forced fitting of components constraining the structure to a particular geometry. The areas which cool more quickly develop residual compressive stresses, while the slower cooling areas develop residual tensile stresses, and a self-balancing or reaction balanced system of residual stresses is formed. The phenomenon of residual stresses is the most challenging in its application in surface modification techniques determining endurance mechanism against fracture and fatigue failures. This paper discusses the mechanism of residual stresses, that how the residual stresses are fanned and what their behavior is under the action of external forces. Such as in the case of a circular bar under limit torque, rectangular beam under limt moment, reclaiming of shafts welds and peening etc. (author)

  13. Radiation environment of the earth

    International Nuclear Information System (INIS)

    Furukawa, Masahide

    2003-01-01

    The radiation environment of the earth consists of natural and artificial radiation. This paper explains the distribution and some exposure examples of natural radiation and the relation between life and natural radiation. The earth was born before about 46 hundreds of millions of years. In the present earth, there are some natural radiations with long half-life originated by the earth. They are 232 Th (141 hundreds of millions of years of half-life), 238 U (45 hundreds of millions of years of half-life) and 40 K (13 hundreds of millions of years of half-life). Natural radiation (α-, β-, and γ-ray) from natural radionuclides exists everywhere in the earth. Natural radio nuclides are heat source of the earth, which is about 0.035 μcal/g/y. γ-ray from them is called as ''the earth's crust γ-ray'', which is about 55 nGy/h average of the world and about 50 nGy/h in Japan. The distribution of γ-ray is depended on the kinds of soil and rock. 222 Rn and 230 Rn are rare gases and the concentration of them in a room is larger than outside. Natural radiations originated from the cosmos are proton, ionizing components, neutron component with muon and electron, 3 H, 14 C and 10 Be. Effect of cosmic rays on birth of life, change of temperature, amount of cloud and ultra resistant cell are stated. (S.Y.)

  14. Our Sustainable Earth

    Science.gov (United States)

    Orbach, Raymond L.

    2013-03-01

    Recent evidence demonstrates that the Earth has been warming monotonically since 1980. Transient to equilibrium temperature changes take centuries to develop, as the upper levels of the ocean are slow to respond to atmospheric temperature changes. Atmospheric CO2 concentrations, from ice core and observatory measurements, display consistent increases from historical averages, beginning in about 1880. They can be associated with the use of coal ecause of the spread of the industrial revolution from Great Britain to the European continent and beyond. The climactic consequence of this human-dominated increase in atmospheric CO2 has been suggested to define a geologic epoch, termed the ``Anthropocene.'' This could be a short term, relatively minor change in global climate, or an extreme deviation that lasts for thousands of years. In order to stabilize global temperatures, sharp reductions in CO2 emissions are required: an 80% reduction beginning in 2050. U.S. emissions have declined sharply recently because of market conditions leading to the substitution of natural gas for coal for electricity generation. Whether this is the best use for this resource may be questioned, but it nevertheless reduces CO2 production by 67% from a coal-fired power plant, well on the way to the 80% reduction required for global temperature stabilization. Current methods for CO2 capture and storage are not cost effective, and have been slow (if not absent) to introduce at scale. This paper describes research into some potentially economically feasible approaches: cost-effective capture and storage of CO2 from injection of flue gas into subterranean methane-saturated aquifers at the surface; fuels from sunlight without CO2 production; and large-scale electrical energy storage for intermittent (and even constant) electricity generating sources.

  15. Earth - South America (first frame of Earth Spin Movie)

    Science.gov (United States)

    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.

  16. Earth system commitments due to delayed mitigation

    International Nuclear Information System (INIS)

    Pfister, Patrik L; Stocker, Thomas F

    2016-01-01

    As long as global CO 2 emissions continue to increase annually, long-term committed Earth system changes grow much faster than current observations. A novel metric linking this future growth to policy decisions today is the mitigation delay sensitivity (MDS), but MDS estimates for Earth system variables other than peak temperature (ΔT max ) are missing. Using an Earth System Model of Intermediate Complexity, we show that the current emission increase rate causes a ΔT max increase roughly 3–7.5 times as fast as observed warming, and a millenial steric sea level rise (SSLR) 7–25 times as fast as observed SSLR, depending on the achievable rate of emission reductions after the peak of emissions. These ranges are only slightly affected by the uncertainty range in equilibrium climate sensitivity, which is included in the above values. The extent of ocean acidification at the end of the century is also strongly dependent on the starting time and rate of emission reductions. The preservable surface ocean area with sufficient aragonite supersaturation for coral reef growth is diminished globally at an MDS of roughly 25%–80% per decade. A near-complete loss of this area becomes unavoidable if mitigation is delayed for a few years to decades. Also with respect to aragonite, 12%–18% of the Southern Ocean surface become undersaturated per decade, if emission reductions are delayed beyond 2015–2040. We conclude that the consequences of delaying global emission reductions are much better captured if the MDS of relevant Earth system variables is communicated in addition to current trends and total projected future changes. (letter)

  17. Earth observation from the manned low Earth orbit platforms

    Science.gov (United States)

    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.

  18. EarthN: A new Earth System Nitrogen Model

    OpenAIRE

    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...

  19. Sun-Earth Day, 2001

    Science.gov (United States)

    Adams, Mitzi L.; Mortfield, P.; Hathaway, D. H.; Whitaker, Ann F. (Technical Monitor)

    2001-01-01

    To promote awareness of the Sun-Earth connection, NASA's Marshall Space Flight Center, in collaboration with the Stanford SOLAR Center, sponsored a one-day Sun-Earth Day event on April 27, 2001. Although "celebrated" on only one day, teachers and students from across the nation, prepared for over a month in advance. Workshops were held in March to train teachers. Students performed experiments, results of which were shared through video clips and an internet web cast. Our poster includes highlights from student experiments (grades 2 - 12), lessons learned from the teacher workshops and the event itself, and plans for Sun-Earth Day 2002.

  20. The earth's shape and gravity

    CERN Document Server

    Garland, G D; Wilson, J T

    2013-01-01

    The Earth's Shape and Gravity focuses on the progress of the use of geophysical methods in investigating the interior of the earth and its shape. The publication first offers information on gravity, geophysics, geodesy, and geology and gravity measurements. Discussions focus on gravity measurements and reductions, potential and equipotential surfaces, absolute and relative measurements, and gravity networks. The text then elaborates on the shape of the sea-level surface and reduction of gravity observations. The text takes a look at gravity anomalies and structures in the earth's crust; interp

  1. Incapacidad laboral total

    Directory of Open Access Journals (Sweden)

    Orlando Díaz Tabares

    1997-04-01

    Full Text Available Se realizó un estudio longitudinal, descriptivo y retrospectivo con el objetivo de conocer el comportamiento de la incapacidad permanente para el trabajo en el municipio "San Cristóbal" durante el decenio 1982-1991, y se aplicó el método de encuesta por el que se recogieron datos que fueron extraídos del modelo oficial de peritaje médico laboral y de la entrevista con el peritado. Los resultados fueron plasmados en tablas de contingencias donde se relacionan las variables por cada año estudiado, y se aplicó la prueba estadística de chi cuadrado. El número de individuos dictaminados con incapacidad laboral total fue de 693; predominó en reportes el año 1988 con 114 casos y muy discretamente el sexo femenino sobre el masculino, el grupo etáreo de 45 a 54 años con 360 casos y la artrosis como entidad valorada por ortopedia, con análisis estadísticos significativos. No resultó estadísticamente significativo, el predominio de la hipertensión arterial sistémica entre las entidades valoradas por la especialidad de medicina interna como causas de incapacidad laboral. Fue muy significativa la variación del número de dictaminados por la comisión en cada uno de los años estudiados y que el porcentaje de ellos que se encontraban realizando trabajos que demandan esfuerzo físico de moderado a intenso al momento de aplicar la encuesta, ascendió al 64,9.A longitudinal, descriptive and retrospective study was conducted in order to know the behavior of permanent labor disability at the municipality of San Cristóbal during 1982-1991. A survey was done to collect data taken from the official model of medical inspections and from the interview with the disabled worker. The results were shown in contingency tables where the variables are related by every year studied. The chi square statistical test was applied. The number of individuals with labor disability was 693. As for reports, the year 1988 predominated with 114. There was a discreet

  2. Closed model of the earth's magnetosphere

    International Nuclear Information System (INIS)

    Piddington, J.H.

    1979-01-01

    The existence of large-scale motions within the earth's magnetosphere and that of a long magnetotail were predicted in 1960 as results of a hypothetical frictional interaction between the solar wind and the geomagnetic field. The boundary layer model of this interaction involves the flow of magnetosheath plasma in a magnetospheric boundary layer. The flow is across magnetic field lines, and so the layer must be polarized, with a space charge field nearly balancing the induction field V x B. The space charge tends to discharge through the ionosphere, thus providing some magnetic and related activity as well as the Lorentz frictional force. This closed magnetosphere model has been largely neglected in favor of the reconnection model but is now strongly supported by observational results and their interpretation as follows. (1) The evidence for the reconnection model, increasing activity with a southward interplanetary field and invasion of the polar caps by flare particles, is shown to be equally compatible with the closed field model. (2) The magnetotail grows by the motions of closed flux tubes through the dawn and dusk meridians, a process which depends on the nature of the boundary between magnetosphere and magnetosheath plasmas and perhaps also on the solar wind dynamo. Both of these features depend, in turn, on the direction of the interplanetary magnetic field. (3) Closed field lines entering the tail may be stretched to a few tens of earth radii and then contract back to the corotating magnetosphere. Others enter the long tail and are stretched to hundreds of earth radii and so are pervious to fast solar particles. (4) A new model of the magnetospheric substorm involves the entry of closed field lines into the tail and their rapid return to the corotating magnetosphere. The return is due, first, to the release of their trapped plasma as it becomes electrically polarized and, second, to mounting magnetic and plasma stresses in the inflated magnetotail

  3. Rare earths from uranium mineralization occurrences in the Permian of the Gemericum, the Western Carpathians

    International Nuclear Information System (INIS)

    Rojkovic, I.; Medved, J.; Walzel, E.; Posta, S.; Sulovsky, P.

    1989-01-01

    Uranium mineralization in the Permian of the Gemericium is accompanied by apatite, monazite and xenotime. The study of rare earth elements distribution is based on the results of instrumental neutron activation analysis and optical emission spectroscopy analysis of rocks and energy-dispersive X-ray microanalyses of minerals. The main light rare earth elements bearing mineral is monazite; for heavy rare earth elements it is xenotime. The rocks accompanying uranium mineralization have increased rare earth elements contents. The mobilization and concentration of uranium mineralization took place during the Alpine metallogenic processes. These processes were also associated with rare earth elements mobilization is which total and selective enrichment in light rare earth elements and heavy rare earth elements was observed. (author). 12 figs., 6 tabs., 5 refs

  4. The spectral response of Buxus sempervirens to different types of environmental stress - A laboratory experiment

    Science.gov (United States)

    de Jong, Steven M.; Addink, Elisabeth A.; Hoogenboom, Priscilla; Nijland, Wiebe

    2012-11-01

    The European Mediterranean regions are expected to encounter drier summer conditions and warmer temperatures for the winter of +2 °C and of +5 °C for the summer in the next six decennia. As a result the natural vegetation will face harsher conditions due to lower water availability, longer summer droughts and higher temperatures resulting in plant stress conditions. To monitor vegetation conditions like stress and leaf area index dynamics in our study area in Mediterranean France we use earth observation techniques like imaging spectroscopy. To assist image analysis interpretation we carried out a laboratory experiment to investigate the spectral and visible response of Buxus sempervirens, a common Mediterranean species, to five different types of stress: drought, drought-and-heat, light deprivation, total saturation and chlorine poisoning. For 52 days plants were subjected to stress. We collected data on the visible and spectral signs, and calculated thirteen vegetation indices. The plant's response time to different stress types varied from 10 to 32 days. Spectroscopic techniques revealed plant stress up to 15 days earlier than visual inspection. Visible signs of stress of the plants included curling and shrinking of the leaves, de-colouring of the leaves, leaves becoming breakable, opening up of the plant's canopy and sagging of the branches. Spectral signs of stress occurred first in the water absorption bands at 1450 and 1940 nm, followed by reduced absorption in the visible wavelengths, and next by reduced reflectance in near infrared. Light deprivation did not result in any stress signs, while drought, drought and heat and chlorine poisoning resulted in significant stress. The spectral response did not show differences for different stress types. Analysis of the vegetation indices identified the Carter-2 (R695/R760), the Red-Green Index (R690/R550) and the Vogelman-2 (R734 - R747)/(R715 + R726) as the best performing ones to identify stress. The lab

  5. Modelling earth current precursors in earthquake prediction

    Directory of Open Access Journals (Sweden)

    R. Di Maio

    1997-06-01

    Full Text Available This paper deals with the theory of earth current precursors of earthquake. A dilatancy-diffusion-polarization model is proposed to explain the anomalies of the electric potential, which are observed on the ground surface prior to some earthquakes. The electric polarization is believed to be the electrokinetic effect due to the invasion of fluids into new pores, which are opened inside a stressed-dilated rock body. The time and space variation of the distribution of the electric potential in a layered earth as well as in a faulted half-space is studied in detail. It results that the surface response depends on the underground conductivity distribution and on the relative disposition of the measuring dipole with respect to the buried bipole source. A field procedure based on the use of an areal layout of the recording sites is proposed, in order to obtain the most complete information on the time and space evolution of the precursory phenomena in any given seismic region.

  6. Oxidative stress

    Directory of Open Access Journals (Sweden)

    Osredkar Joško

    2012-05-01

    Full Text Available The human organism is exposed to the influence of various forms of stress, either physical, psychological or chemical, which all have in common that they may adversely affect our body. A certain amount of stress is always present and somehow directs, promotes or inhibits the functioning of the human body. Unfortunately, we are now too many and too often exposed to excessive stress, which certainly has adverse consequences. This is especially true for a particular type of stress, called oxidative stress. All aerobic organisms are exposed to this type of stress because they produce energy by using oxygen. For this type of stress you could say that it is rather imperceptibly involved in our lives, as it becomes apparent only at the outbreak of certain diseases. Today we are well aware of the adverse impact of radicals, whose surplus is the main cause of oxidative stress. However, the key problem remains the detection of oxidative stress, which would allow us to undertake timely action and prevent outbreak of many diseases of our time. There are many factors that promote oxidative stress, among them are certainly a fast lifestyle and environmental pollution. The increase in oxidative stress can also trigger intense physical activity that is directly associated with an increased oxygen consumption and the resulting formation of free radicals. Considering generally positive attitude to physical activity, this fact may seem at first glance contradictory, but the finding has been confimed by several studies in active athletes. Training of a top athlete daily demands great physical effort, which is also reflected in the oxidative state of the organism. However, it should be noted that the top athletes in comparison with normal individuals have a different defense system, which can counteract the negative effects of oxidative stress. Quite the opposite is true for irregular or excessive physical activity to which the body is not adapted.

  7. Earth as a radio source: terrestrial kilometric radiation. Progress report

    International Nuclear Information System (INIS)

    Gurnett, D.A.

    1974-02-01

    Radio wave experiments on the IMP-6 and 8 satellites have shown that the earth emits very intense electromagnetic radiation in the frequency range from about 50 kHz to 500 kHz. A peak intensity the total power emitted in this frequency range is about 1 billion watts. The earth is, therefore, a very intense planetary radio source, with a total power output comparable to the decametric radio emission from Jupiter. This radio emission from the earth is referred to as terrestrial kilometric radiation. Terrestrial kilometric radiation appears to originate from low altitudes (less than 3.0 Re) in the auroral region. Possible mechanisms which can explain the generation and propagation of the terrestrial kilometric radiation are discussed. (U.S.)

  8. Earth analysis methods, subsurface feature detection methods, earth analysis devices, and articles of manufacture

    Science.gov (United States)

    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.

  9. 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

  10. Work Stress

    OpenAIRE

    Roeters, Anne

    2014-01-01

    Most of us agree that stress is a growing problem within organizations. We hear about the postal workers who had killed fellow employees and supervisors, and then hear that a major cause of tension is at work. Friends tell us that they are stressed due to increased workload and he has to work overtime because the company is restructured. We read the polls that employees complain about the stress in trying to balance family life with the work. Stress is a dynamic condition in which an individu...

  11. The relationship between beginning teachers' stress causes, stress responses, teaching behaviour and attrition

    NARCIS (Netherlands)

    Harmsen, Ruth; Lorenz, Michelle; Maulana, Ridwan; van Veen, Klaas

    2018-01-01

    In this study, the relationships between beginning teachers’ perceived stress causes, stress responses, observed teaching behaviour and attrition is investigated employing structural equation modelling (SEM). A total of 143 BTs were surveyed using the Questionnaire on the Experience and Evaluation

  12. 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

  13. Total and Spectral Solar Irradiance Sensor (TSIS) Project Status

    Science.gov (United States)

    Carlisle, Candace

    2018-01-01

    TSIS-1 studies the Sun's energy input to Earth and how solar variability affects climate. TSIS-1 will measure both the total amount of light that falls on Earth, known as the total solar irradiance (TSI), and how that light is distributed among ultraviolet, visible and infrared wavelengths, called solar spectral irradiance (SSI). TSIS-1 will provide the most accurate measurements of sunlight and continue the long-term climate data record. TSIS-1 includes two instruments: the Total Irradiance Monitor (TIM) and the Spectral Irradiance Monitor (SIM), integrated into a single payload on the International Space Station (ISS). The TSIS-1 TIM and SIM instruments are upgraded versions of the two instruments that are flying on the Solar Radiation and Climate Experiment (SORCE) mission launched in January 2003. NASA Goddard's TSIS project responsibilities include project management, system engineering, safety and mission assurance, and engineering oversight for TSIS-1. TSIS-1 was installed on the International Space Station in December 2017. At the end of the 90-day commissioning phase, responsibility for TSIS-1 operations transitions to the Earth Science Mission Operations (ESMO) project at Goddard for its 5-year operations. NASA contracts with the University of Colorado Laboratory for Atmospheric and Space Physics (LASP) for the design, development and testing of TSIS-1, support for ISS integration, science operations of the TSIS-1 instrument, data processing, data evaluation, calibration and delivery to the Goddard Earth Science Data and Information Services Center (GES DISC).

  14. Children's knowledge of the Earth

    Science.gov (United States)

    Siegal, Michael; Nobes, Gavin; Panagiotaki, Georgia

    2011-03-01

    Children everywhere are fascinated by the sky, stars and Sun. Emerging evidence from cultures throughout the world suggests that even young children can acquire knowledge of the Earth and its place in the Universe.

  15. Encyclopedia of earth system science

    National Research Council Canada - National Science Library

    Nierenberg, William Aaron

    1992-01-01

    .... The very diversity of the articles attests to the complexity of earth system science as a unique interdisciplinary venture to place humanity in a position to move wisely to protect the global habitat...

  16. Measuring Earth's Magnetic Field Simply.

    Science.gov (United States)

    Stewart, Gay B.

    2000-01-01

    Describes a method for measuring the earth's magnetic field using an empty toilet paper tube, copper wire, clear tape, a battery, a linear variable resistor, a small compass, cardboard, a protractor, and an ammeter. (WRM)

  17. Earth Science Education in Morocco

    Science.gov (United States)

    Bouabdelli, Mohamed

    1999-05-01

    The earth sciences are taught in twelve universities in Morocco and in three other institutions. In addition there are three more earth science research institutions. Earth science teaching has been taking place since 1957. The degree system is a four-year degree, split into two two-year blocks and geology is taught within the geology-biology programme for the first part of the degree. 'Classical' geology is taught in most universities, although applied geology degrees are also on offer in some universities. Recently-formed technical universities offer a more innovative approach to Earth Science Education. Teaching is in French, although school education is in Arabic. There is a need for a reform of the curriculum, although a lead is being taken by the technical universities. A new geological mapping programme promises new geological and mining discoveries in the country and prospects of employment for geology graduates.

  18. The Search for Another Earth

    Indian Academy of Sciences (India)

    2016-08-26

    /fulltext/reso/021/07/0641-0652. Keywords. Stars, planets, planetary systems, detection. Abstract. Is there life anywhere else in the vast cosmos?Are there planets similar to the Earth? For centuries,these questions baffled ...

  19. Earth Charter and nuclear energy

    International Nuclear Information System (INIS)

    Grippi, Sidney

    2006-01-01

    The chapter presents Earth Charter, where are listed the principles in 4 sections: 1) respect and take care of the life community; 2) environmental integrity; social and economic welfare; 4) democracy, no-violence and peace

  20. NASA's Earth Science Data Systems

    Science.gov (United States)

    Ramapriyan, H. K.

    2015-01-01

    NASA's Earth Science Data Systems (ESDS) Program has evolved over the last two decades, and currently has several core and community components. Core components provide the basic operational capabilities to process, archive, manage and distribute data from NASA missions. Community components provide a path for peer-reviewed research in Earth Science Informatics to feed into the evolution of the core components. The Earth Observing System Data and Information System (EOSDIS) is a core component consisting of twelve Distributed Active Archive Centers (DAACs) and eight Science Investigator-led Processing Systems spread across the U.S. The presentation covers how the ESDS Program continues to evolve and benefits from as well as contributes to advances in Earth Science Informatics.

  1. A umbrella for the Earth

    International Nuclear Information System (INIS)

    Kunzig, R.

    2009-01-01

    In front of the global warming threat, the 'geo-engineers' foresee some solutions to change the climate of the Earth, like for instance, by hiding part of the solar radiation. Among the solutions one can notice: the injection of sulfur dioxide in the stratosphere, the artificial generation of clouds using sea fog generators, or the putting into orbit of disc-shape screens creating a 100000 km x 12000 km elliptical 'umbrella' between the sun and the Earth. (J.S.)

  2. Rare earth industries: Downstream business

    International Nuclear Information System (INIS)

    2011-01-01

    The value chain of the rare earths business involves mining, extraction, processing, refining and the manufacture of an extensive range of downstream products which find wide applications in such industries including aerospace, consumer electronics, medical, military, automotive, renewable wind and solar energy and telecommunications. In fact the entire gamut of the high-tech industries depends on a sustainable supply of rare earths elements. The explosive demand in mobile phones is an excellent illustration of the massive potential that the rare earths business offers. In a matter of less than 20 years, the number of cell phones worldwide has reached a staggering 5 billion. Soon, going by the report of their growth in sales, the world demand for cell phones may even exceed the global population. Admittedly, the rare earths business does pose certain risks. Top among the risks are the health and safety risks. The mining, extraction and refining of rare earths produce residues and wastes which carry health and safety risks. The residues from the extraction and refining are radioactive, while their effluent waste streams do pose pollution risks to the receiving rivers and waterways. But, as clearly elaborated in a recent report by IAEA experts, there are technologies and systems available to efficiently mitigate such risks. The risks are Rare Earth manageable. However, it is crucial that the risk and waste management procedures are strictly followed and adhered to. This is where effective monitoring and surveillance throughout the life of all such rare earths facilities is crucial. Fortunately, Malaysia's regulatory standards on rare earths follow international standards. In some areas, Malaysia's regulatory regime is even more stringent than the international guidelines. (author)

  3. Rare earth metal alloy magnets

    International Nuclear Information System (INIS)

    Harris, I.R.; Evans, J.M.; Nyholm, P.S.

    1979-01-01

    This invention relates to rare earth metal alloy magnets and to methods for their production. The technique is based on the fact that rare earth metal alloys (for e.g. cerium or yttrium) which have been crumbled to form a powder by hydride formation and decomposition can be used for the fabrication of magnets without the disadvantages inherent in alloy particle size reduction by mechanical milling. (UK)

  4. Non-rocket Earth-Moon transportation system

    Science.gov (United States)

    Bolonkin, A.

    for maneuverability and temporary landing on Earth surface up to 6 hours. If the suggested Transport System is used only for free thrust (9 tons), the system can pull the three supersonic transport (passenger) aircraft or produces up to 40 millions watt energy. The Moon's trajectory has an eccentricity. If the main cable is strong enough, the Moon may be used for free lifting (traveling) a payload (men cabins) to an altitude of about 60,000 kilometers every 27 days. For this case, the length of the main cable from the Moon to the container does not change and when the Moon increases its distance from the Moon to the Earth, the Moon lifts the space ship. The cabin could land back on the planet at any time if it is allowed to slide along the cable. The Moon's energy can be used also for an inexpensive trip (passenger system) around of the Earth by having the moon "drag" an aircraft around the planet (using the Moon as free thrust engine) with supersonic speed, about 440 m/s (Max Number is 1.5). Project . Free Trips to the Moon. The following is some data estimating the Moon Transport System which provides an inexpensive payload transfer between the Earth and the Moon. The system has three cables. Every cable can keep the force 3 tons. Material of cable has specific strong k=4*10^7. All cables have cross-sectional areas of an equal stress. A minimal cross-sectional area of cable is 0.42 mm2 (diameter 0,73 mm) and maximum cross-sectional area is 1.9 mm2 (1.56 mm). The mass of the main cable is 1300 tons. The total mass of the main cable plus the two container cables (for delivering a mass 3000 kg) equals 3900 tons. An unlimited and inexpensive means of the payload delivery between the Earth and the Moon could be obtained. An elapsed time to the Moon trip with a speed of 6 km/sec would be about 18.5 hours. The annual deliver capably is 1320 tons (or 10,000 tourists) in every direction. If one cable will be damaged two others will be used for safe people and repairing. The

  5. Rare-earth elements

    Science.gov (United States)

    Van Gosen, Bradley S.; Verplanck, Philip L.; Seal, Robert R.; Long, Keith R.; Gambogi, Joseph; Schulz, Klaus J.; DeYoung,, John H.; Seal, Robert R.; Bradley, Dwight C.

    2017-12-19

    The rare-earth elements (REEs) are 15 elements that range in atomic number from 57 (lanthanum) to 71 (lutetium); they are commonly referred to as the “lanthanides.” Yttrium (atomic number 39) is also commonly regarded as an REE because it shares chemical and physical similarities and has affinities with the lanthanides. Although REEs are not rare in terms of average crustal abundance, the concentrated deposits of REEs are limited in number.Because of their unusual physical and chemical properties, the REEs have diverse defense, energy, industrial, and military technology applications. The glass industry is the leading consumer of REE raw materials, which are used for glass polishing and as additives that provide color and special optical properties to the glass. Lanthanum-based catalysts are used in petroleum refining, and cerium-based catalysts are used in automotive catalytic converters. The use of REEs in magnets is a rapidly increasing application. Neodymium-iron-boron magnets, which are the strongest known type of magnets, are used when space and weight are restrictions. Nickel-metal hydride batteries use anodes made of a lanthanum-based alloys.China, which has led the world production of REEs for decades, accounted for more than 90 percent of global production and supply, on average, during the past decade. Citing a need to retain its limited REE resources to meet domestic requirements as well as concerns about the environmental effects of mining, China began placing restrictions on the supply of REEs in 2010 through the imposition of quotas, licenses, and taxes. As a result, the global rare-earth industry has increased its stockpiling of REEs; explored for deposits outside of China; and promoted new efforts to conserve, recycle, and substitute for REEs. New mine production began at Mount Weld in Western Australia, and numerous other exploration and development projects noted in this chapter are ongoing throughout the world.The REE-bearing minerals are

  6. Greenhouse Earth: A Traveling Exhibition

    International Nuclear Information System (INIS)

    Booth, W.H.; Caesar, S.

    1992-09-01

    The Franklin Institute Science Museum provided an exhibit entitled the Greenhouse Earth: A Traveling Exhibition. This 3500 square-foot exhibit on global climate change was developed in collaboration with the Association of Science-Technology Centers. The exhibit opened at The Franklin Institute on February 14, 1992, welcoming 291,000 visitors over its three-month stay. During its three-year tour, Greenhouse Earth will travel to ten US cities, reaching two million visitors. Greenhouse Earth aims to deepen public understanding of the scientific issues of global warming and the conservation measures that can be taken to slow its effects. The exhibit features hands-on exhibitry, interactive computer programs and videos, a theater production, a ''demonstration cart,'' guided tours, and lectures. supplemental educational programs at the Institute included a teachers preview, a symposium on climate change, and a ''satellite field trip.'' The development of Greenhouse Earth included front-end and formative evaluation procedures. Evaluation includes interviews with visitors, prototypes, and summative surveys for participating museums. During its stay in Philadelphia, Greenhouse Earth was covered by the local and national press, with reviews in print and broadcast media. Greenhouse Earth is the first large-scale museum exhibit to address global climate change

  7. Next-generation Digital Earth.

    Science.gov (United States)

    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.

  8. Reduce, Reuse, Recycle: Good Earth and the Electronics Dilemma

    Science.gov (United States)

    Descy, Don E.

    2007-01-01

    According to the National Safety Council, 63 million computers became obsolete in 2005 alone, and it is estimated that the total number in storage in 2007 numbers upwards of 500 million computers (Earth 911, 2007). This article describes the steps that one should take before disposing of an obsolete computer. First and foremost, all personal…

  9. Journal of Earth System Science | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Earth System Science; Volume 122; Issue 1. Contribution of some ozone depleting substances (ODS) and greenhouse gases (GHGs) on total column zone growth at Srinagar (34°N, 74.8°), India. P K Jana D K Saha D Sarkar. Volume 122 Issue 1 February 2013 pp 239-252 ...

  10. Earth Construction and Landfill Disposal Options for Slaker Grits

    OpenAIRE

    Risto Pöykiö; G. Watkins; H. Nurmesniemi and O. Dahl

    2010-01-01

    Slaker grits, an industrial residue originating from the chemical recovery process at sulfate (kraft) pulp mills, are typically disposed of to landfill in Finland. However, due to the relatively low total heavy metal and low leachable heavy metal, chloride, fluoride, sulfate, Dissolved O rganic Carbon (DOC) and Total Dissolved Solids (TDS) concentrations, the residue is a potential earth construction material. This paper gives an overview of the relevant Finnish legislation on the use of indu...

  11. Residual stresses

    International Nuclear Information System (INIS)

    Macherauch, E.

    1978-01-01

    Residual stresses are stresses which exist in a material without the influence of external powers and moments. They come into existence when the volume of a material constantly changes its form as a consequence of mechanical, thermal, and/or chemical processes and is hindered by neighbouring volumes. Bodies with residual stress are in mechanical balance. These residual stresses can be manifested by means of all mechanical interventions disturbing this balance. Acoustical, optical, radiological, and magnetical methods involving material changes caused by residual stress can also serve for determining residual stress. Residual stresses have an ambivalent character. In technical practice, they are feared and liked at the same time. They cause trouble because they can be the cause for unexpected behaviour of construction elements. They are feared since they can cause failure, in the worst case with catastrophical consequences. They are appreciated, on the other hand, because, in many cases, they can contribute to improvements of the material behaviour under certain circumstances. But they are especially liked for their giving convenient and (this is most important) mostly uncontrollable explanations. For only in very few cases we have enough knowledge and possibilities for the objective evaluation of residual stresses. (orig.) [de

  12. 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

  13. Geopotential Stress

    DEFF Research Database (Denmark)

    Schiffer, Christian; Nielsen, S.B.

    Density heterogeneity in the Earth’s lithosphere causes lateral pressure variations. Horizontal gradients of the vertically integrated lithostatic pressure, the Geopotential Energy (GPE), are a source of stresses (Geopotential Stress) that contribute to the Earth’s Stress Field. In theory the GPE...... is linearly related to the lithospheric part of the Geoid. The Geopotential Stress can be calculated if either the density structure and as a consequence the GPE or the lithospheric contribution to the Geoid is known. The lithospheric Geoid is usually obtained by short pass filtering of satellite Geoid...... are not entirely suitable for the stress calculations but can be compiled and adjusted. We present an approach in which a global lithospheric density model based on CRUST2.0 is obtained by simultaneously fitting topography and surface heat flow in the presence of isostatic compensation and long-wavelength lateral...

  14. Baltic Earth - Earth System Science for the Baltic Sea Region

    Science.gov (United States)

    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

  15. EarthLabs - Investigating Hurricanes: Earth's Meteorological Monsters

    Science.gov (United States)

    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

  16. Observed tidal braking in the earth/moon/sun system

    Science.gov (United States)

    Christodoulidis, D. C.; Smith, D. E.; Williamson, R. G.; Klosko, S. M.

    1987-01-01

    The low degree and order terms in the spherical harmonic model of the tidal potential were observed through the perturbations which are induced on near-earth satellite orbital motions. Evaluations of tracking observations from 17 satellites and a GEM-T1 geopotential model were used in the tidal recovery which was made in the presence of over 600 long-wavelength coefficients from 32 major and minor tides. Wahr's earth tidal model was used as a basis for the recovery of the ocean tidal terms. Using this tidal model, the secular change in the moon's mean motion due to tidal dissipation was found to be -25.27 + or - 0.61 arcsec/century squared. The estimation of lunar acceleration agreed with that observed from lunar laser ranging techniques (-24.9 + or - 1.0 arcsec/century squared), with the corresponding tidal braking of earth's rotation being -5.98 + or - 0.22 x 10 to the minus 22 rad/second squared. If the nontidal braking of the earth due to the observed secular change in the earth's second zonal harmonic is considered, satellite techniques yield a total value of the secular change of the earth's rotation rate of -4.69 + or - 0.36 x 10 to the minus 22 rad/second squared.

  17. Regional positioning using a low Earth orbit satellite constellation

    Science.gov (United States)

    Shtark, Tomer; Gurfil, Pini

    2018-02-01

    Global and regional satellite navigation systems are constellations orbiting the Earth and transmitting radio signals for determining position and velocity of users around the globe. The state-of-the-art navigation satellite systems are located in medium Earth orbits and geosynchronous Earth orbits and are characterized by high launching, building and maintenance costs. For applications that require only regional coverage, the continuous and global coverage that existing systems provide may be unnecessary. Thus, a nano-satellites-based regional navigation satellite system in Low Earth Orbit (LEO), with significantly reduced launching, building and maintenance costs, can be considered. Thus, this paper is aimed at developing a LEO constellation optimization and design method, using genetic algorithms and gradient-based optimization. The preliminary results of this study include 268 LEO constellations, aimed at regional navigation in an approximately 1000 km × 1000 km area centered at the geographic coordinates [30, 30] degrees. The constellations performance is examined using simulations, and the figures of merit include total coverage time, revisit time, and geometric dilution of precision (GDOP) percentiles. The GDOP is a quantity that determines the positioning solution accuracy and solely depends on the spatial geometry of the satellites. Whereas the optimization method takes into account only the Earth's second zonal harmonic coefficient, the simulations include the Earth's gravitational field with zonal and tesseral harmonics up to degree 10 and order 10, Solar radiation pressure, drag, and the lunisolar gravitational perturbation.

  18. Rare Earth Elements - A New Challenge for the World Economy

    Directory of Open Access Journals (Sweden)

    Cristina Bumbac

    2013-01-01

    Full Text Available Rare Earth Elements or Rare Earth Metals (REM are a collection of seventeen chemical elements in the periodic table, namely scandium, yttrium and fifteen lanthanides. The term "rare earth" arises from the rare earth minerals from which they were first isolated. They are uncommon oxide-type minerals (earths found in Gandolinite extracted from one mine in Sweden. The first discovery was made in 1794, but it was only in 1940 that the scientist Frank Spedding developed an ion exchange procedure for separating and purifying the REM. For the next decades, they were hardly used in some "minor" industrial fields. Only after 2000 their importance grew, once the multitude of possibilities to use them was discovered due to technological progress. Now REM are incorporated into almost all modern technological devices: superconductors, magnets, electronic polishers, refining catalysts hybrid car components and military techniques. They are used in small quantities, but due to their extraordinary properties the prices are very high. The main problem is that China dominates this market, with 97% of total global supply. The highest concentration of rare earth metals are in Inner Mongolia in China, Mountain Pass in California U.S.A. and in Mount Weld in Australia. The developed countries are far behind China regarding production and are indeed depending on Chinese exports. Hence, there is a difficult situation on this particular market, with an uncertain future.

  19. Financial stress spillovers in advanced economies

    NARCIS (Netherlands)

    Apostolakis, G.; Papadopoulos, A.

    2014-01-01

    Financial stress co-movements are positively associated with crisis periods. Dynamic conditional correlations increase during periods of high uncertainty. The US is the dominant transmitter of financial stress spillovers. The total stress spillover index explains 19.9% of the forecast error

  20. Tidal Friction in the Earth and Ocean

    Science.gov (United States)

    Ray, R. D.

    2006-12-01

    "Tidal Friction" is a classic subject in geophysics, with ties to some of the great scientists of the Victorian era. The subject has been reinvigorated over the past decade by space geodesy, and particularly by the Topex/Poseidon satellite altimeter mission. In fact, the topic has now taken on some significance in oceanography, with potential implications for problems of mixing, thermocline maintenance, and the thermohaline circulation. Likewise, tidal measurements have become sufficiently precise to reveal new information about the solid earth. In this respect, the tidal force is an invaluable "probe" of the earth, at frequencies well outside the seismic band. This talk will "follow the energy" of tides while noting some important geophysical implications at each stage. In the present earth-moon-sun configuration, energy for tides is extracted from the earth's rotation. Ancient eclipses bear witness to this, and the discrepancy between Babylonian (and other) observations and tidal predictions yields unique information about the mantle and the overlying fluid envelope. Complementary information comes from tidal anelasticity estimates, which are now available at frequencies ranging from semidiurnal to fortnightly, monthly, and 18.6 years. These data, when combined with various kinds of gravity measurements, are relevant to the present-day sea-level problem. Solid-earth tidal dissipation represents less than 5% of the system total. As has long been realized, the largest energy sink is the ocean. About 70% of the oceanic dissipation occurs in shallow seas (the traditional sink) and 30% in the deep ocean, generally near rugged bottom topography. The latter represents a substantial amount of power, roughly 1 gigawatt, available for generation of internal tides and other baroclinic motions. Experiments like HOME are helping unravel the links between barotropic tides, internal tides, turbulence, and mixing. The latter opens possible linkages to climate, and recent work

  1. Learn to manage stress

    Science.gov (United States)

    Stress - managing; Stress - recognizing; Stress - relaxation techniques ... LEARN TO RECOGNIZE STRESS The first step in managing stress is recognizing it in your life. Everyone feels stress in a different way. ...

  2. Smouldering Subsurface Fires in the Earth System

    Science.gov (United States)

    Rein, Guillermo

    2010-05-01

    Smouldering fires, the slow, low-temperature, flameless form of combustion, are an important phenomena in the Earth system. These fires propagate slowly through organic layers of the forest ground and are responsible for 50% or more of the total biomass consumed during wildfires. Only after the 2002 study of the 1997 extreme haze event in South-East Asia, the scientific community recognised the environmental and economic threats posed by subsurface fires. This was caused by the spread of vast biomass fires in Indonesia, burning below the surface for months during the El Niño climate event. It has been calculated that these fires released between 0.81 and 2.57 Gton of carbon gases (13-40% of global emissions). Large smouldering fires are rare events at the local scale but occur regularly at a global scale. Once ignited, they are particularly difficult to extinguish despite extensive rains or fire-fighting attempts and can persist for long periods of time (months, years) spreading over very extensive areas of forest and deep into the soil. Indeed, these are the oldest continuously burning fires on Earth. Earth scientists are interested in smouldering fires because they destroy large amounts of biomass and cause greater damage to the soil ecosystem than flaming fires do. Moreover, these fires cannot be detected with current satellite remote sensing technologies causing inconsistencies between emission inventories and model predictions. Organic soils sustain smouldering fire (hummus, duff, peat and coal) which total carbon pool exceeds that of the world's forests or the atmosphere. This have important implications for climate change. Warmer temperatures at high latitudes are resulting in unprecedented permafrost thaw that is leaving large soil carbon pools exposed to fires. Because the CO2 flux from peat fires has been measured to be about 3000 times larger that the natural degradation flux, permafrost thaw is a risk for greater carbon release by fire and subsequently

  3. The Sun-earth Imbalance radiometer for a direct measurement of the net heating of the earth

    Science.gov (United States)

    Dewitte, Steven; Karatekin, Özgür; Chevalier, Andre; Clerbaux, Nicolas; Meftah, Mustapha; Irbah, Abdanour; Delabie, Tjorven

    2015-04-01

    It is accepted that the climate on earth is changing due to a radiative energy imbalance at the top of the atmosphere, up to now this radiation imbalance has not been measured directly. The measurement is challenging both in terms of space-time sampling of the radiative energy that is leaving the earth and in terms of accuracy. The incoming solar radiation and the outgoing terrestrial radiation are of nearly equal magnitude - of the order of 340 W/m² - resulting in a much smaller difference or imbalance of the order of 1 W/m². The only way to measure the imbalance with sufficient accuracy is to measure both the incoming solar and the outgoing terrestrial radiation with the same instrument. Based on our 30 year experience of measuring the Total Solar Irradiance with the Differential Absolute RADiometer (DIARAD) type of instrument and on our 10 year experience of measuring the Earth Radiation Budget with the Geostationary Earth Radiation Budget (GERB) instrument on Meteosat Second Generation, we propose an innovative constellation of Sun-earth IMBAlance (SIMBA) radiometer cubesats with the ultimate goal to measure the Sun-earth radiation imbalance. A first Simba In Orbit Demonstration satellite is scheduled for flight with QB50 in 2015. It is currently being developed as ESA's first cubesat through an ESA GSTP project. In this paper we will give an overview of the Simba science objectives and of the current satellite and payload development status.

  4. Total oxidant status, total antioxidant capacity and ischemia modified albumin levels in children with celiac disease.

    Science.gov (United States)

    Sayar, Ersin; Özdem, Sebahat; Uzun, Gülbahar; İşlek, Ali; Yılmaz, Aygen; Artan, Reha

    2015-01-01

    In our study, we aimed to investigate ischemia modified albumin (IMA) as an oxidative stress marker, as well as other oxidant and antioxidant markers that have not been evaluated in children with celiac disease. A total of 37 pediatric patients who were diagnosed with celiac disease (CD) and 29 healthy children were enrolled in this prospective study. We evaluated the IMA, total oxidant status, total antioxidant capacity, sulfhydryl, and advanced oxidation protein products in all of the subjects. We also compared the levels at the time of the diagnosis, and following a gluten-free diet (GFD) in the children with CD. While the IMA and the other oxidant marker levels were significantly higher in the patient group compared to the control group, the antioxidant marker levels were found to be significantly lower in the patient group, compared to the control group. We also determined that the tissue transglutaminase IgA showed a highly positive correlation, and that the IMA showed a moderately positive correlation with the Marsh-Oberhuber histopathological stage. Additionally, the IMA and other oxidant marker levels were significantly lower, while the antioxidant marker levels were significantly higher after the GFD, compared to the pre-diet period. We detected that oxidative stress played a role in the pathogenesis of CD, and that this could be evaluated using oxidative stress markers, which would regress after the GFD. We also detected that IMA is a marker that shows a correlation with the histopathological stage, and may be used in the diagnosis.

  5. Towards Big Earth Data Analytics: The EarthServer Approach

    Science.gov (United States)

    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

  6. Rare earth industry in India

    International Nuclear Information System (INIS)

    Singh, D.S.

    2016-01-01

    Rare Earths (RE) comprises of 17 elements i.e. elements from atomic No. 57-71 (lanthanide series) along with yttrium (atomic No. 39) and scandium (atomic No. 21). They exhibit special electronic, magnetic, optical and catalytic properties. The first 7 elements in the lanthanide series from atomic Nos. 57 to 63 (La to Eu) are called Light Rare Earths (LRE), while the remaining elements from atomic Nos. 64 to 71 (Gd to Lu) are grouped as Heavy Rare Earths (HRE). Scandium and Yttrium have properties similar to HRE. The concentration of the REs in the earth's crust is as high as some other elements including that of copper. The only difference is that REs do not occur as separate minerals amenable for easy exploration and mining and are widely distributed across the earth's surface, hence they are called as REs. Resources In India, monazite has been the principal source of RE. It occurs in association with other heavy minerals, such as ilmenite, rutile, zircon etc. in the beach sands and inland placer deposits. The monazite content in this assemblage varies from negligible quantity to as high as 5%. As per AMD resource estimation, the reported resource of monazite in India is about 11.93 million tons which corresponds with about 6.9 million tons of RE oxides. Although India possesses large deposits of monazite, the heavier RE are not present in sufficient quantities in this mineral. (author)

  7. Smarter Earth Science Data System

    Science.gov (United States)

    Huang, Thomas

    2013-01-01

    The explosive growth in Earth observational data in the recent decade demands a better method of interoperability across heterogeneous systems. The Earth science data system community has mastered the art in storing large volume of observational data, but it is still unclear how this traditional method scale over time as we are entering the age of Big Data. Indexed search solutions such as Apache Solr (Smiley and Pugh, 2011) provides fast, scalable search via keyword or phases without any reasoning or inference. The modern search solutions such as Googles Knowledge Graph (Singhal, 2012) and Microsoft Bing, all utilize semantic reasoning to improve its accuracy in searches. The Earth science user community is demanding for an intelligent solution to help them finding the right data for their researches. The Ontological System for Context Artifacts and Resources (OSCAR) (Huang et al., 2012), was created in response to the DARPA Adaptive Vehicle Make (AVM) programs need for an intelligent context models management system to empower its terrain simulation subsystem. The core component of OSCAR is the Environmental Context Ontology (ECO) is built using the Semantic Web for Earth and Environmental Terminology (SWEET) (Raskin and Pan, 2005). This paper presents the current data archival methodology within a NASA Earth science data centers and discuss using semantic web to improve the way we capture and serve data to our users.

  8. Experimental Measurement of In Situ Stress

    Science.gov (United States)

    Tibbo, Maria; Milkereit, Bernd; Nasseri, Farzine; Schmitt, Douglas; Young, Paul

    2016-04-01

    The World Stress Map data is determined by stress indicators including earthquake focal mechanisms, in situ measurement in mining, oil and gas boreholes as well as the borehole cores, and geologic data. Unfortunately, these measurements are not only infrequent but sometimes infeasible, and do not provide nearly enough data points with high accuracy to correctly infer stress fields in deep mines around the world. Improvements in stress measurements of Earth's crust is fundamental to several industries such as oil and gas, mining, nuclear waste management, and enhanced geothermal systems. Quantifying the state of stress and the geophysical properties of different rock types is a major complication in geophysical monitoring of deep mines. Most stress measurement techniques involve either the boreholes or their cores, however these measurements usually only give stress along one axis, not the complete stress tensor. The goal of this project is to investigate a new method of acquiring a complete stress tensor of the in situ stress in the Earth's crust. This project is part of a comprehensive, exploration geophysical study in a deep, highly stressed mine located in Sudbury, Ontario, Canada, and focuses on two boreholes located in this mine. These boreholes are approximately 400 m long with NQ diameters and are located at depths of about 1300 - 1600 m and 1700 - 2000 m. Two borehole logging surveys were performed on both boreholes, October 2013 and July 2015, in order to perform a time-lapse analysis of the geophysical changes in the mine. These multi-parameter surveys include caliper, full waveform sonic, televiewer, chargeability (IP), and resistivity. Laboratory experiments have been performed on borehole core samples of varying geologies from each borehole. These experiments have measured the geophysical properties including elastic modulus, bulk modulus, P- and S-wave velocities, and density. The apparatus' used for this project are geophysical imaging cells capable

  9. Models of the earth's core

    Science.gov (United States)

    Stevenson, D. J.

    1981-01-01

    Combined inferences from seismology, high-pressure experiment and theory, geomagnetism, fluid dynamics, and current views of terrestrial planetary evolution lead to models of the earth's core with five basic properties. These are that core formation was contemporaneous with earth accretion; the core is not in chemical equilibrium with the mantle; the outer core is a fluid iron alloy containing significant quantities of lighter elements and is probably almost adiabatic and compositionally uniform; the more iron-rich inner solid core is a consequence of partial freezing of the outer core, and the energy release from this process sustains the earth's magnetic field; and the thermodynamic properties of the core are well constrained by the application of liquid-state theory to seismic and labroatory data.

  10. Revolutions that made the earth

    CERN Document Server

    Lenton, Tim

    2013-01-01

    The Earth that sustains us today was born out of a few remarkable, near-catastrophic revolutions, started by biological innovations and marked by global environmental consequences. The revolutions have certain features in common, such as an increase in the complexity, energy utilization, and information processing capabilities of life. This book describes these revolutions, showing the fundamental interdependence of the evolution of life and its non-living environment. We would not exist unless these upheavals had led eventually to 'successful' outcomes - meaning that after each one, at length, a new stable world emerged. The current planet-reshaping activities of our species may be the start of another great Earth system revolution, but there is no guarantee that this one will be successful. This book explains what a successful transition through it might look like, if we are wise enough to steer such a course. This book places humanity in context as part of the Earth system, using a new scientific synthe...

  11. Stress Management

    Science.gov (United States)

    ... with regions of your brain that control mood, motivation and fear. The body's stress-response system is ... problems Headaches Heart disease Sleep problems Weight gain Memory and concentration impairment That's why it's so important ...

  12. Stressing academia?

    DEFF Research Database (Denmark)

    Opstrup, Niels; Pihl-Thingvad, Signe

    Incongruences between the individual and the organizational work context are potential stressors. The present study focuses on the relationship between a complementary need-supply fit and Danish researchers’ self-perceived job stress. Strain is expected to increase as organizational supplies fall...... hand, the fit on “hard” dimensions as salary, financial rewards and career opportunities is found to be unrelated to the researchers’ self-perceived stress-level. The fit with regard to job security is an important exception, however....... to “soft” dimensions as freedom and independence in the job, personal and professional development at work, and receiving peer recognition is highly significant for the researchers’ self-perceived stress-level. The better the fit is the lower stress-levels the researchers’ on average report. On the other...

  13. Mapping Tectonic Stress Using Earthquakes

    International Nuclear Information System (INIS)

    Arnold, Richard; Townend, John; Vignaux, Tony

    2005-01-01

    An earthquakes occurs when the forces acting on a fault overcome its intrinsic strength and cause it to slip abruptly. Understanding more specifically why earthquakes occur at particular locations and times is complicated because in many cases we do not know what these forces actually are, or indeed what processes ultimately trigger slip. The goal of this study is to develop, test, and implement a Bayesian method of reliably determining tectonic stresses using the most abundant stress gauges available - earthquakes themselves.Existing algorithms produce reasonable estimates of the principal stress directions, but yield unreliable error bounds as a consequence of the generally weak constraint on stress imposed by any single earthquake, observational errors, and an unavoidable ambiguity between the fault normal and the slip vector.A statistical treatment of the problem can take into account observational errors, combine data from multiple earthquakes in a consistent manner, and provide realistic error bounds on the estimated principal stress directions.We have developed a realistic physical framework for modelling multiple earthquakes and show how the strong physical and geometrical constraints present in this problem allow inference to be made about the orientation of the principal axes of stress in the earth's crust

  14. Free oscillation of the Earth

    Directory of Open Access Journals (Sweden)

    Y. Abedini

    2000-06-01

    Full Text Available   This work is a study of the Earths free oscillations considering a merge of solid and liquid model. At the turn of 19th century Geophysicists presented the theory of the free oscillations for a self-gravitating, isotropic and compressible sphere. Assuming a steel structure for an Earth size sphere, they predicted a period of oscillation of about 1 hour. About 50 years later, the free oscillations of stars was studied by Cowling and others. They classified the oscillation modes of the stars into acoustic and gravity modes on the basis of their driving forces. These are pressure and buoyancy forces respectively. The earliest measurements for the period of the free oscillations of the Earth was made by Benyove from a study of Kamchathca earthquake. Since then, the Geophysicists have been trying to provide a theoretical basis for these measurements. Recently, the theory concerning oscillations of celestial fluids is extended by Sobouti to include the possible oscillations of the Earthlike bodies. Using the same technique, we study the free oscillations of a spherically symmetric, non-rotating and elastic model for the Earth.   We used the actual data of the Earths interior structure in our numerical calculations. Numerical results show that there exist three distinct oscillation modes namely acoustic, gravity and toroidal modes. These modes are driven by pressure, buoyancy and shear forces respectively. The shear force is due to the elastic properties of the solid part of the Earth. Our numerical results are consistent with the seismic data recorded from earthquake measurements.

  15. Universities Earth System Scientists Program

    Science.gov (United States)

    Estes, John E.

    1995-01-01

    This document constitutes the final technical report for the National Aeronautics and Space Administration (NASA) Grant NAGW-3172. This grant was instituted to provide for the conduct of research under the Universities Space Research Association's (USRA's) Universities Earth System Scientist Program (UESSP) for the Office of Mission to Planet Earth (OMTPE) at NASA Headquarters. USRA was tasked with the following requirements in support of the Universities Earth System Scientists Programs: (1) Bring to OMTPE fundamental scientific and technical expertise not currently resident at NASA Headquarters covering the broad spectrum of Earth science disciplines; (2) Conduct basic research in order to help establish the state of the science and technological readiness, related to NASA issues and requirements, for the following, near-term, scientific uncertainties, and data/information needs in the areas of global climate change, clouds and radiative balance, sources and sinks of greenhouse gases and the processes that control them, solid earth, oceans, polar ice sheets, land-surface hydrology, ecological dynamics, biological diversity, and sustainable development; (3) Evaluate the scientific state-of-the-field in key selected areas and to assist in the definition of new research thrusts for missions, including those that would incorporate the long-term strategy of the U.S. Global Change Research Program (USGCRP). This will, in part, be accomplished by study and evaluation of the basic science needs of the community as they are used to drive the development and maintenance of a global-scale observing system, the focused research studies, and the implementation of an integrated program of modeling, prediction, and assessment; and (4) Produce specific recommendations and alternative strategies for OMTPE that can serve as a basis for interagency and national and international policy on issues related to Earth sciences.

  16. Stress Management

    Directory of Open Access Journals (Sweden)

    Prof.Univ. Dr. Paul Marinescu

    2007-05-01

    Full Text Available In the post-modern management organizational leaders have the obligation of protecting their employees against factors that could cause damages to their potentially wealthy lives. Stress is such a factor. We shall attempt by means of the present article to draw attention on certain general aspects that should be taken into account in drafting plans for fighting against and diminishing the stress faced by the employees

  17. Stress fractures

    International Nuclear Information System (INIS)

    Berquist, T.H.; Cooper, K.L.; Pritchard, D.J.

    1985-01-01

    The diagnosis of a stress fracture should be considered in patients presented with pain after a change in activity, especially if the activity is strenuous and the pain is in the lower extremities. Since evidence of the stress fracture may not be apparent for weeks on routine radiographs, proper use of other imaging techniques will allow an earlier diagnosis. Prompt diagnosis is especially important in the femur, where displacement may occur

  18. Human impact on the planet: an earth system science perspective and ethical considerations

    Science.gov (United States)

    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

  19. Near-Earth Object Survey Simulation Software

    Science.gov (United States)

    Naidu, Shantanu P.; Chesley, Steven R.; Farnocchia, Davide

    2017-10-01

    There is a significant interest in Near-Earth objects (NEOs) because they pose an impact threat to Earth, offer valuable scientific information, and are potential targets for robotic and human exploration. The number of NEO discoveries has been rising rapidly over the last two decades with over 1800 being discovered last year, making the total number of known NEOs >16000. Pan-STARRS and the Catalina Sky Survey are currently the most prolific NEO surveys, having discovered >1600 NEOs between them in 2016. As next generation surveys such as Large Synoptic Survey Telescope (LSST) and the proposed Near-Earth Object Camera (NEOCam) become operational in the next decade, the discovery rate is expected to increase tremendously. Coordination between various survey telescopes will be necessary in order to optimize NEO discoveries and create a unified global NEO discovery network. We are collaborating on a community-based, open-source software project to simulate asteroid surveys to facilitate such coordination and develop strategies for improving discovery efficiency. Our effort so far has focused on development of a fast and efficient tool capable of accepting user-defined asteroid population models and telescope parameters such as a list of pointing angles and camera field-of-view, and generating an output list of detectable asteroids. The software takes advantage of the widely used and tested SPICE library and architecture developed by NASA’s Navigation and Ancillary Information Facility (Acton, 1996) for saving and retrieving asteroid trajectories and camera pointing. Orbit propagation is done using OpenOrb (Granvik et al. 2009) but future versions will allow the user to plug in a propagator of their choice. The software allows the simulation of both ground-based and space-based surveys. Performance is being tested using the Grav et al. (2011) asteroid population model and the LSST simulated survey “enigma_1189”.

  20. Greater physiological and behavioral effects of interrupted stress pattern compared to daily restraint stress in rats.

    Directory of Open Access Journals (Sweden)

    Wei Zhang

    Full Text Available Repeated stress can trigger a range of psychiatric disorders, including anxiety. The propensity to develop abnormal behaviors after repeated stress is related to the severity, frequency and number of stressors. However, the pattern of stress exposure may contribute to the impact of stress. In addition, the anxiogenic nature of repeated stress exposure can be moderated by the degree of coping that occurs, and can be reflected in homotypic habituation to the repeated stress. However, expectations are not clear when a pattern of stress presentation is utilized that diminishes habituation. The purpose of these experiments is to test whether interrupted stress exposure decreases homotypic habituation and leads to greater effects on anxiety-like behavior in adult male rats. We found that repeated interrupted restraint stress resulted in less overall homotypic habituation compared to repeated daily restraint stress. This was demonstrated by greater production of fecal boli and greater corticosterone response to restraint. Furthermore, interrupted restraint stress resulted in a lower body weight and greater adrenal gland weight than daily restraint stress, and greater anxiety-like behavior in the elevated plus maze. Control experiments demonstrated that these effects of the interrupted pattern could not be explained by differences in the total number of stress exposures, differences in the total number of days that the stress periods encompased, nor could it be explained as a result of only the stress exposures after an interruption from stress. These experiments demonstrate that the pattern of stress exposure is a significant determinant of the effects of repeated stress, and that interrupted stress exposure that decreases habituation can have larger effects than a greater number of daily stress exposures. Differences in the pattern of stress exposure are therefore an important factor to consider when predicting the severity of the effects of repeated

  1. Physical Processes Controlling Earth's Climate

    Science.gov (United States)

    Genio, Anthony Del

    2013-01-01

    As background for consideration of the climates of the other terrestrial planets in our solar system and the potential habitability of rocky exoplanets, we discuss the basic physics that controls the Earths present climate, with particular emphasis on the energy and water cycles. We define several dimensionless parameters relevant to characterizing a planets general circulation, climate and hydrological cycle. We also consider issues associated with the use of past climate variations as indicators of future anthropogenically forced climate change, and recent advances in understanding projections of future climate that might have implications for Earth-like exoplanets.

  2. Setting to earth for computer

    International Nuclear Information System (INIS)

    Gallego V, Luis Eduardo; Montana Ch, Johny Hernan; Tovar P, Andres Fernando; Amortegui, Francisco

    2000-01-01

    The program GMT allows the analysis of setting to earth for tensions DC and AC (of low frequency) of diverse configurations composed by cylindrical electrodes interconnected, in a homogeneous land or stratified (two layers). This analysis understands among other aspects: calculation of the setting resistance to earth, elevation of potential of the system (GPR), calculation of current densities in the conductors, potentials calculation in which point on the land surface (profile and surfaces), tensions calculation in passing and of contact, also, it carries out the interpretation of resistivity measures for Wenner and Schlumberger methods, finding a model of two layers

  3. Earthquake swarms and the semidiurnal solid earth tide

    Energy Technology Data Exchange (ETDEWEB)

    Klein, F W

    1976-01-01

    Several correlations between peak earthquake activity during swarms and the phase and stress orientation of the calculated solid earth tide are described. The events correlating with the tide are clusters of swarm earthquakes. Swarm clusters from many sequences recorded over several years are used. Significant tidal correlations (which have less than a 5% chance of being observed if earthquakes were random) are found in the Reykjanes Peninsula in Iceland, the central Mid-Atlantic Ridge, the Imperial Valley and northern Gulf of California, and larger (m/sub b/ greater than or equal to 5.0) aftershocks of the 1965 Rat Islands earthquake. In addition, sets of larger single earthquakes on Atlantic and north-east Pacific fracture zones are significantly correlated with the calculated solid tide. No tidal correlation, however, could be found for the Matsushiro Japan swarm of 1965 to 1967. The earthquake-tide correlations other than those of the Reykjanes Peninsula and Mid-Atlantic Ridge can be interpreted as triggering caused by enhancement of the tectonic stress by tidal stress, i.e. the alignment of fault and tidal principal stresses. All tidal correlations except in the Aleutians are associated with oceanic rifts or their landward extensions. If lithospheric plates are decoupled at active rifts, then tidal stresses channeled along the lithospheric stress guide may be concentrated at ridge-type plate boundaries. Tidal triggering of earthquakes at rifts may reflect this possible amplification of tidal strains in the weakened lithosphere at ridges. 25 figures, 2 tables.

  4. 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

  5. Early Earth(s) Across Time and Space

    Science.gov (United States)

    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

  6. Multi sensor reanalysis of total ozone

    Directory of Open Access Journals (Sweden)

    R. J. van der A

    2010-11-01

    Full Text Available A single coherent total ozone dataset, called the Multi Sensor Reanalysis (MSR, has been created from all available ozone column data measured by polar orbiting satellites in the near-ultraviolet Huggins band in the last thirty years. Fourteen total ozone satellite retrieval datasets from the instruments TOMS (on the satellites Nimbus-7 and Earth Probe, SBUV (Nimbus-7, NOAA-9, NOAA-11 and NOAA-16, GOME (ERS-2, SCIAMACHY (Envisat, OMI (EOS-Aura, and GOME-2 (Metop-A have been used in the MSR. As first step a bias correction scheme is applied to all satellite observations, based on independent ground-based total ozone data from the World Ozone and Ultraviolet Data Center. The correction is a function of solar zenith angle, viewing angle, time (trend, and effective ozone temperature. As second step data assimilation was applied to create a global dataset of total ozone analyses. The data assimilation method is a sub-optimal implementation of the Kalman filter technique, and is based on a chemical transport model driven by ECMWF meteorological fields. The chemical transport model provides a detailed description of (stratospheric transport and uses parameterisations for gas-phase and ozone hole chemistry. The MSR dataset results from a 30-year data assimilation run with the 14 corrected satellite datasets as input, and is available on a grid of 1× 1 1/2° with a sample frequency of 6 h for the complete time period (1978–2008. The Observation-minus-Analysis (OmA statistics show that the bias of the MSR analyses is less than 1% with an RMS standard deviation of about 2% as compared to the corrected satellite observations used.

  7. Costs and benefits of rare earth screens

    International Nuclear Information System (INIS)

    Taylor, F.E.

    1977-01-01

    The British Institute of Radiology has submitted evidence (Royal Commission on Environmental Pollution, 1976, Sixth Report, Nuclear Power and the Environment. Cmnd 6618, HMSO, London) leading to the conclusion that the introduction of rare earth screens in medical radiography is not financially practical at present in the U.K. This conclusion is questioned. The cost of reducing the genetic dose from medical radiography should be compared with the costs of reducing that from other sources such as nuclear power wastes, since the risks are to future generations in both cases. The cost of reducing public exposure by the use of rare earth screens in U.K. hospitals is calculated to be about Pound1 per man-rad; a total annual genetic collective dose of nearly 300,000 man-rad could be saved. An anomalous situation is presented by the great discrepancies between this cost, and published estimates both of the cost of the detriment associated with the genetic collective dose and of the value incorporated into the design objective for nuclear reactors. (U.K.)

  8. Heliotropic dust rings for Earth climate engineering

    Science.gov (United States)

    Bewick, R.; Lücking, C.; Colombo, C.; Sanchez, J. P.; McInnes, C. R.

    2013-04-01

    This paper examines the concept of a Sun-pointing elliptical Earth ring comprised of dust grains to offset global warming. A new family of non-Keplerian periodic orbits, under the effects of solar radiation pressure and the Earth's J2 oblateness perturbation, is used to increase the lifetime of the passive cloud of particles and, thus, increase the efficiency of this geoengineering strategy. An analytical model is used to predict the orbit evolution of the dust ring due to solar-radiation pressure and the J2 effect. The attenuation of the solar radiation can then be calculated from the ring model. In comparison to circular orbits, eccentric orbits yield a more stable environment for small grain sizes and therefore achieve higher efficiencies when the orbit decay of the material is considered. Moreover, the novel orbital dynamics experienced by high area-to-mass ratio objects, influenced by solar radiation pressure and the J2 effect, ensure the ring will maintain a permanent heliotropic shape, with dust spending the largest portion of time on the Sun facing side of the orbit. It is envisaged that small dust grains can be released from a circular generator orbit with an initial impulse to enter an eccentric orbit with Sun-facing apogee. Finally, a lowest estimate of 1 × 1012 kg of material is computed as the total mass required to offset the effects of global warming.

  9. Stress field models from Maxwell stress functions: southern California

    Science.gov (United States)

    Bird, Peter

    2017-08-01

    The lithospheric stress field is formally divided into three components: a standard pressure which is a function of elevation (only), a topographic stress anomaly (3-D tensor field) and a tectonic stress anomaly (3-D tensor field). The boundary between topographic and tectonic stress anomalies is somewhat arbitrary, and here is based on the modeling tools available. The topographic stress anomaly is computed by numerical convolution of density anomalies with three tensor Green's functions provided by Boussinesq, Cerruti and Mindlin. By assuming either a seismically estimated or isostatic Moho depth, and by using Poisson ratio of either 0.25 or 0.5, I obtain four alternative topographic stress models. The tectonic stress field, which satisfies the homogeneous quasi-static momentum equation, is obtained from particular second derivatives of Maxwell vector potential fields which are weighted sums of basis functions representing constant tectonic stress components, linearly varying tectonic stress components and tectonic stress components that vary harmonically in one, two and three dimensions. Boundary conditions include zero traction due to tectonic stress anomaly at sea level, and zero traction due to the total stress anomaly on model boundaries at depths within the asthenosphere. The total stress anomaly is fit by least squares to both World Stress Map data and to a previous faulted-lithosphere, realistic-rheology dynamic model of the region computed with finite-element program Shells. No conflict is seen between the two target data sets, and the best-fitting model (using an isostatic Moho and Poisson ratio 0.5) gives minimum directional misfits relative to both targets. Constraints of computer memory, execution time and ill-conditioning of the linear system (which requires damping) limit harmonically varying tectonic stress to no more than six cycles along each axis of the model. The primary limitation on close fitting is that the Shells model predicts very sharp

  10. METHODS FOR THE DETERMINATION OF TOTAL ORGANIC ...

    Science.gov (United States)

    Organic matter in soils and sediments is widely distributed over the earth's surface occurring in almost all terrestrial and aquatic environments (Schnitzer, 1978). Soils and sediments contain a large variety of organic materials ranging from simple sugars and carbohydrates to the more complex proteins, fats, waxes, and organic acids. Important characteristics of the organic matter include their ability to: form water-soluble and water- insoluble complexes with metal ions and hydrous oxides; interact with clay minerals and bind particles together; sorb and desorb both naturally-occurring and anthropogenically-introduced organic compounds; absorb and release plant nutrients; and hold water in the soil environment. As a result of these characteristics, the determination of total organic carbon (a measure of one of the chemical components of organic matter that is often used as an indicator of its presence in a soil or sediment) is an essential part of any site characterization since its presence or absence can markedly influence how chemicals will react in the soil or sediment. Soil and sediment total organic carbon (TOC) determinations are typically requested with contaminant analyses as part of an ecological risk assessment data package. TOC contents may be used qualitatively to assess the nature of the sampling location (e.g., was it a depositional area) or may be used to normalize portions of the analytical chemistry data set (e.g., equilibrium partitioning).

  11. Gamma-Ray Bursts and the Earth: Exploration of Atmospheric, Biological, Climatic, and Biogeochemical Effects

    Science.gov (United States)

    Thomas, Brian C.; Melott, Adrian L.; Jackman, Charles H.; Laird, Claude M.; Medvedev, Mikhail V.; Stolarski, Richard S.; Gehrels, Neil; Cannizzo, John K.; Hogan, Daniel P.; Ejzak, Larissa M.

    2005-11-01

    Gamma-ray bursts (GRBs) are likely to have made a number of significant impacts on the Earth during the last billion years. The gamma radiation from a burst within a few kiloparsecs would quickly deplete much of the Earth's protective ozone layer, allowing an increase in solar UVB radiation reaching the surface. This radiation is harmful to life, damaging DNA and causing sunburn. In addition, NO2 produced in the atmosphere would cause a decrease in visible sunlight reaching the surface and could cause global cooling. Nitric acid rain could stress portions of the biosphere, but the increased nitrate deposition could be helpful to land plants. We have used a two-dimensional atmospheric model to investigate the effects on the Earth's atmosphere of GRBs delivering a range of fluences, at various latitudes, at the equinoxes and solstices, and at different times of day. We have estimated DNA damage levels caused by increased solar UVB radiation, reduction in solar visible light due to NO2 opacity, and deposition of nitrates through rainout of HNO3. For the ``typical'' nearest burst in the last billion years, we find globally averaged ozone depletion up to 38%. Localized depletion reaches as much as 74%. Significant global depletion (at least 10%) persists up to about 7 yr after the burst. Our results depend strongly on time of year and latitude over which the burst occurs. The impact scales with the total fluence of the GRB at the Earth but is insensitive to the time of day of the burst and its duration (1-1000 s). We find DNA damage of up to 16 times the normal annual global average, well above lethal levels for simple life forms such as phytoplankton. The greatest damage occurs at mid- to low latitudes. We find reductions in visible sunlight of a few percent, primarily in the polar regions. Nitrate deposition similar to or slightly greater than that currently caused by lightning is also observed, lasting several years. We discuss how these results support the

  12. The Greatest Show on Earth

    Indian Academy of Sciences (India)

    Darwin and Alfred Russel Wallace: life on earth had evolved ... over long epochs, the pace of change was infinitesimal. ... Thanks to the work of the Japanese theoreti- cian Motoo ... pleasure-minus-expenditure balance is posi- tive. This way of ...

  13. Earth Day 2012: Greening Government

    Centers for Disease Control (CDC) Podcasts

    2012-04-19

    This podcast describes sustainability efforts at CDC in relation to Earth Day celebrations and details agency greenhouse gas reduction strategies and successes.  Created: 4/19/2012 by Office of the Chief Operating Officer (OCOO)/ Chief Sustainability Office (CSO).   Date Released: 4/23/2012.

  14. NASA Earth Science Education Collaborative

    Science.gov (United States)

    Schwerin, T. G.; Callery, S.; Chambers, L. H.; Riebeek Kohl, H.; Taylor, J.; Martin, A. M.; Ferrell, T.

    2016-12-01

    The NASA Earth Science Education Collaborative (NESEC) is led by the Institute for Global Environmental Strategies with partners at three NASA Earth science Centers: Goddard Space Flight Center, Jet Propulsion Laboratory, and Langley Research Center. This cross-organization team enables the project to draw from the diverse skills, strengths, and expertise of each partner to develop fresh and innovative approaches for building pathways between NASA's Earth-related STEM assets to large, diverse audiences in order to enhance STEM teaching, learning and opportunities for learners throughout their lifetimes. These STEM assets include subject matter experts (scientists, engineers, and education specialists), science and engineering content, and authentic participatory and experiential opportunities. Specific project activities include authentic STEM experiences through NASA Earth science themed field campaigns and citizen science as part of international GLOBE program (for elementary and secondary school audiences) and GLOBE Observer (non-school audiences of all ages); direct connections to learners through innovative collaborations with partners like Odyssey of the Mind, an international creative problem-solving and design competition; and organizing thematic core content and strategically working with external partners and collaborators to adapt and disseminate core content to support the needs of education audiences (e.g., libraries and maker spaces, student research projects, etc.). A scaffolded evaluation is being conducted that 1) assesses processes and implementation, 2) answers formative evaluation questions in order to continuously improve the project; 3) monitors progress and 4) measures outcomes.

  15. Studying the Earth from space

    Science.gov (United States)

    ,

    1981-01-01

    Space age technology contains a key to increased knowledge about the Earth's resources; this key is remote sensing detecting the nature or condition of something without actually touching it. An early and still most useful form of remote sensing is photography which records the

  16. The Earth as a Polder

    Indian Academy of Sciences (India)

    that the resources of the earth as a whole will .... tion of land and underground water sources as a ... oil; the different visions and desires of old and .... the world, one showing its political hot spots, ... Guns, Germs, and Steel, and The Rise and.

  17. The Dynamic Earth: Recycling Naturally!

    Science.gov (United States)

    Goldston, M. Jenice; Allison, Elizabeth; Fowler, Lisa; Glaze, Amanda

    2013-01-01

    This article begins with a thought-provoking question: What do you think of when you hear the term "recycle?" Many think about paper, glass, aluminum cans, landfills, and reducing waste by reusing some of these materials. How many of us ever consider the way the systems of Earth dynamically recycle its materials? In the following…

  18. Lessons from Earth's Deep Time

    Science.gov (United States)

    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.

  19. Refresher Course on Earth Sciences

    Indian Academy of Sciences (India)

    Information and Announcements ... Introduction: Geoscience education in India is in the throes of a serious crisis and any paradigm ... considerations: geology needs to be taught as an earth system science, linked with cognate ... viable and employment-generating management of natural resources: the global trend of.

  20. Paleoseismology: evidence of earth activity

    Czech Academy of Sciences Publication Activity Database

    Nováková, Lucie

    2016-01-01

    Roč. 105, č. 5 (2016), 1467-1469 ISSN 1437-3254 Institutional support: RVO:67985891 Keywords : Paleoseismology * Colluvial wedge * White Creek Fault _ * Greendale Fault * San Andreas Fault * Paganica Fault Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 2.283, year: 2016

  1. The two earths of Eratosthenes.

    Science.gov (United States)

    Carman, Christián Carlos; Evans, James

    2015-03-01

    In the third century B.C.E., Eratosthenes of Cyrene made a famous measurement of the circumference of the Earth. This was not the first such measurement, but it is the earliest for which significant details are preserved. Cleomedes gives a short account of Eratosthenes' method, his numerical assumptions, and the final result of 250,000 stades. However, many ancient sources attribute to Eratosthenes a result of 252,000 stades. Historians have attempted to explain the second result by supposing that Eratosthenes later made better measurements and revised his estimate or that the original result was simply rounded to 252,000 to have a number conveniently divisible by 60 or by 360. These explanations are speculative and untestable. However, Eratosthenes' estimates of the distances of the Sun and Moon from the Earth are preserved in the doxographical literature. This essay shows that Eratosthenes' result of 252,000 stades for the Earth's circumference follows from a solar distance that is attributed to him. Thus it appears that Eratosthenes computed not only a lower limit for the size of the Earth, based on the assumption that the Sun is at infinity, but also an upper limit, based on the assumption that the Sun is at a finite distance. The essay discusses the consequences for our understanding of his program.

  2. Earth as an extrasolar planet: Earth model validation using EPOXI earth observations.

    Science.gov (United States)

    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

  3. 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

  4. Dartmouth College Earth Sciences Mobile Field Program

    Science.gov (United States)

    Meyer, E. E.; Osterberg, E. C.; Dade, W. B.; Sonder, L. J.; Renshaw, C. E.; Kelly, M. A.; Hawley, R. L.; Chipman, J. W.; Mikucki, J.; Posmentier, E. S.; Moore, J. R.

    2011-12-01

    For the last 50 years the Department of Earth Sciences at Dartmouth College has offered a term-long, undergraduate field program, informally called "the Stretch". A student typically enrolls during fall quarter of his or her junior year soon after choosing a major or minor. The program thus provides valuable field context for courses that a student will take during the remainder of his or her undergraduate career. Unlike many traditional field camps that focus on one particular region, the Stretch is a mobile program that currently travels through Western North America, from the Canadian Rockies to the Grand Canyon. The program spans two and a half months, during which time undergraduates, graduate TAs, and faculty live, work, and learn collaboratively. Dartmouth College faculty members sequentially teach individual 1- to 2-week segments that focus on their interests and expertise; currently, there are a total of eight segments led by eleven faculty members. Consequently, topics are diverse and include economic geology, geobiology, geomorphology, glaciology, glacial geology, geophysics, hydrogeology, paleontology, stratigraphy, structure and tectonics, and volcanology. The field localities are equally varied, including the alpine glaciers of western Alberta, the national parks of Montana, Wyoming and Utah, the eastern Sierra Nevada, the southern Great Basin, and highlight such classic geological field locales as Sheep Mountain in Wyoming's Bighorn Basin, Death Valley, and the Grand Canyon. Overall, the program aims to: 1) give students a broad perspective on the timing and nature of the processes that resulted in the landscape and underlying geology of western North America; and 2) introduce students to a wide variety of geological environments, field techniques, and research equipment. Students emerge from the program with wide-ranging exposure to active research questions as well as a working knowledge of core field skills in the earth sciences. Stretch students

  5. Development of an earth pressure model for design of earth retaining structures in piedmont soil.

    Science.gov (United States)

    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...

  6. Magnetically levitated space elevator to low-earth orbit.

    Energy Technology Data Exchange (ETDEWEB)

    Hull, J. R.; Mulcahy, T. M.

    2001-07-02

    The properties of currently available NbTi superconductor and carbon-fiber structural materials enable the possibility of constructing a magnetically levitated space elevator from the earth's surface up to an altitude of {approx} 200 km. The magnetic part of the elevator consists of a long loop of current-carrying NbTi, composed of one length that is attached to the earth's surface in an east-west direction and a levitated-arch portion. The critical current density of NbTi is sufficiently high that these conductors will stably levitate in the earth's magnetic field. The magnetic self-field from the loop increases the levitational force and for some geometries assists levitational stability. The 200-km maximum height of the levitated arch is limited by the allowable stresses of the structural material. The loop is cryogenically cooled with helium, and the system utilizes intermediate pumping and cooling stations along both the ground and the levitated portion of the loop, similar to other large terrestrial cryogenic systems. Mechanically suspended from the basic loop is an elevator structure, upon which mass can be moved between the earth's surface and the top of the loop by a linear electric motor or other mechanical or electrical means. At the top of the loop, vehicles may be accelerated to orbital velocity or higher by rocket motors, electromagnetic propulsion, or hybrid methods.

  7. Magnetically levitated space elevator to low-earth orbit

    International Nuclear Information System (INIS)

    Hull, J. R.; Mulcahy, T. M.

    2001-01-01

    The properties of currently available NbTi superconductor and carbon-fiber structural materials enable the possibility of constructing a magnetically levitated space elevator from the earth's surface up to an altitude of(approx) 200 km. The magnetic part of the elevator consists of a long loop of current-carrying NbTi, composed of one length that is attached to the earth's surface in an east-west direction and a levitated-arch portion. The critical current density of NbTi is sufficiently high that these conductors will stably levitate in the earth's magnetic field. The magnetic self-field from the loop increases the levitational force and for some geometries assists levitational stability. The 200-km maximum height of the levitated arch is limited by the allowable stresses of the structural material. The loop is cryogenically cooled with helium, and the system utilizes intermediate pumping and cooling stations along both the ground and the levitated portion of the loop, similar to other large terrestrial cryogenic systems. Mechanically suspended from the basic loop is an elevator structure, upon which mass can be moved between the earth's surface and the top of the loop by a linear electric motor or other mechanical or electrical means. At the top of the loop, vehicles may be accelerated to orbital velocity or higher by rocket motors, electromagnetic propulsion, or hybrid methods

  8. Global Carbon Cycle of the Precambrian Earth

    DEFF Research Database (Denmark)

    Wiewióra, Justyna

    The carbon isotopic composition of distinct Archaean geological records provides information about the global carbon cycle and emergence of life on early Earth. We utilized carbon isotopic records of Greenlandic carbonatites, diamonds, graphites, marbles, metacarbonates and ultramafic rocks...... in the surface environment and recycled back into the mantle In the third manuscript we investigate the carbon cycle components, which have maintained the carbon isotope composition of the mantle constant through time. Assuming constant organic ratio of the total carbon burial (f), we show that increased.......1‰) and metacarbonate ( -6.1 ± 0.1‰ to +1.5 ± 0.0‰) rocks from the ~3.8 Ga Isua Supracrustal Belt as resulting from the Rayleigh distillation process, which affected the ultramafic reservoir with initial δ13C between -2‰ and 0‰. Due to its high primary δ13C signature, carbon in the Isuan magnesite was most likely...

  9. Water in the Earth's Interior: Distribution and Origin

    Science.gov (United States)

    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

  10. Professional stress

    Directory of Open Access Journals (Sweden)

    Stanojević Dragana Z.

    2011-01-01

    Full Text Available Job stress is a line, for the person at work hired adverse physiological, psychological and behavioral reactions to situations in which job requirements are not in accordance with its capabilities, abilities and needs. Sources of stress at work are numerous. Personal factors: personality types have been most studied so far, environmental changes and demographic characteristics as well. Interpersonal stress inducing factors act and influence to the occurrence of many psychosomatic diseases. Psychosocial climate and relationships which are prevented or encouraged such as: cooperation and competition, trust and suspicion certainly affect to the appearance of professional stress. The way of leadership is very important. Organizational factors are the type of work, work time, noncompliance of the job, the introduction of new ethnologies, the conflict of personal roles, fear of job loss, bad physical conditions of working environment. The consequences of stress at work are numerous: at the cognitive level, the emotional level, the production plan, the health, plan reduces the immune system that cause a variety of psychosomatic illnesses and accidents at work.

  11. Comparison of Serum Concentrations of Total Cholesterol and Total ...

    African Journals Online (AJOL)

    Tuberculosis (TB) is one of the most dangerous tropical diseases that complicates HIV infection in Nigeria to date. Over two million Nigerians are known to be infected with TB and many more are at risk of the infection. Serum concentrations of total cholesterol and total lipid of 117 female TB patients attending chest clinic at ...

  12. Changes in total and differential white cell counts, total lymphocyte ...

    African Journals Online (AJOL)

    Background: Published reports on the possible changes in the various immune cell populations, especially the total lymphocyte and CD4 cell counts, during the menstrual cycle in Nigerian female subjects are relatively scarce. Aim: To determine possible changes in the total and differential white blood cell [WBC] counts, ...

  13. Behaviour of Rare Earth Elements during the Earth's core formation

    Science.gov (United States)

    Faure, Pierre; Bouhifd, Mohamed Ali; Boyet, Maud; Hammouda, Tahar; Manthilake, Geeth

    2017-04-01

    Rare Earth Elements (REE) are classified in the refractory group, which means that they have a high temperature condensation and their volatility-controlled fractionation is limited to high-temperature processes. Anomalies have been measured for Eu, Yb and Sm, which are the REE with the lowest condensation temperatures in CAIs and chondrules (e.g. [1]). REE are particularly abundant in the sulfides of enstatite chondrites, 100 to 1000 times the CI value [e.g. 2,3], proving that these elements are not strictly lithophile under extremely reducing conditions. However by investigating experimentally the impact of Earth's core formation on the behavior of Sm and Nd, we have shown the absence of fractionation between Sm and Nd during the segregation of the metallic phase [4]. Recently, Wohlers and Wood [5] proposed that Nd and Sm could be fractionated in presence of a S-rich alloy phase. However, their results were obtained at pressure and temperature conditions below the plausible conditions of the Earth's core formation. Clearly, large pressure range needs to be covered before well-constrained model can be expected. Furthermore, our preliminary metal-silicate partitioning results show that Ce and Eu have higher metal/silicate partition coefficients than their neighboring elements, and that the presence of sulphur enhances the relative difference between partition coefficients. In this presentation, we will present and discuss new metal-silicate partition coefficients of all REE at a deep magma ocean at pressures ranging from those of the uppermost upper mantle ( 5 GPa) to a maximum pressure expected in the range of 20 GPa, temperatures ranging from 2500 to about 3000 K, and oxygen fugacities within IW-1 to IW-5 (1 to 5 orders of magnitude lower than the iron-wüstite buffer). We will discuss the effect of S, as well as the effect of H2O on the behaviour of REE during the Earth's core formation: recent models suggest that contrary to currently accepted beliefs, the

  14. The size and shape of the near-Earth asteroid belt

    Science.gov (United States)

    Rabinowitz, David L.

    1994-01-01

    Evidence was recently reported for the existence of a near-Earth belt of small, Earth-approaching asteroids (SEAs) with diameters less than approximately 50 m. This result was based upon observations made with the Spacewatch Telescope of the University of Arizona during the course of an ongoing search for Earth-approaching asteroids. Using a model to describe the effects of observational bias, it was shown that the orbits observed for SEAs are inconsistent with the orbits of Earth approaches larger than approximately 1 km, and imply a relatively high fraction of Earth-like orbits among the SEAs. In this paper, new observations are included and the bias model is extended in order to quantify the number of SEAs within the near-Earth belt and to further constrain their orbital distribution. The calculation shows that relative to larger Earth approachers. SEAs are deficient in Aten-type orbits for which the semimajor axis is less than 1.0 AU. Instead, nearly all SEAs with aphelia less than 1.4 AU (5 +/- 3% of the total population) have perihelia between 0.9 and 1.1 AU, thus defining a near-Earth belt. Those SEAs with aphelia greater than 1.4 AU, however, have a distribution of orbits that are indistinguishable from the orbits of larger Earth approachers. Taking the near-Earth belt into account does not significantly alter the previously determined enhancement in the number of SEAs the previously determined enhancement in the number of SEAs compared to an extrapolation of the number of larger Earth approachers. At approximately 10 m, the enhancement factor is 40 to within a factor of 2. Also, the RMS impact velocity of SEAs with Earth (17 km/sec) is nearly the same as for larger Earth approachers (18 km/sec).

  15. EDITORIAL: A physicist's journey to the centre of the Earth

    Science.gov (United States)

    Hipkin, Roger

    1999-07-01

    It is a paradox that, despite it being the planet on which all our experience is founded, the bulk Earth is as inaccessible as a remote galaxy. In South African diamond mines, man has penetrated about 3 km into the solid Earth; intact core from boreholes has been recovered from about 7 km and, in the Kola Peninsula of northern Russia, drill chippings have been sluiced up from about 13 km. Nevertheless, even if we had the resources to pepper the outer layer with exploratory boreholes, direct observation of the remaining 99% of the Earth's volume will always remain an impossibility. And yet we know some quite detailed properties of the interior of the Earth. Contrary to primitive cosmologies inspired by watching volcanoes erupt, and although below 2890 km there is a core of molten steel, we know that only in rare, shallow and isolated pockets are the rocks of the Earth's interior molten. The interior of the Earth is like an onion-skin: properties (density, electrical conductivity, sound speed etc) change mainly with depth. Taking the Earth's response to stress as one example, the material behaves like a brittle elastic solid only to depths of about 10-20 km. Below that, Earth materials exhibit the properties of both a solid and a liquid: to short-period effects like sound waves, they respond as a conventional solid but, when subjected to long-period stress, they can also flow like a liquid with a very high viscosity. Viscosity is initially controlled by the increasing mobility of atoms as temperature increases (viscosity decreases from about 1025 Pa s in the upper 20 km to about 1020 Pa s at a depth of 250 km); but atomic mobility is then offset by the counteracting effects of increasing pressure (viscosity increases to perhaps 1023 Pa s at 2500 km). We also have a quantitative physical picture of Earth behaviour stretching back over 4.5 billion years, despite having only 4500 years of recorded scientific observations about the Earth. Using the same physics that

  16. Stress Analysis

    DEFF Research Database (Denmark)

    Burcharth, Hans F.

    The following types of forces contribute to the stresses in a Dolos in a pack exposed to waves: 1)Gravity forces Compaction forces (mainly due to settlements, gravity and flow forces) 2) Flow forces 3) Impact forces (impacts between moving concrete blocks)......The following types of forces contribute to the stresses in a Dolos in a pack exposed to waves: 1)Gravity forces Compaction forces (mainly due to settlements, gravity and flow forces) 2) Flow forces 3) Impact forces (impacts between moving concrete blocks)...

  17. Welding stresses

    International Nuclear Information System (INIS)

    Poirier, J.; Barbe, B.; Jolly, N.

    1976-01-01

    The aim is to show how internal stresses are generated and to fix the orders of magnitude. A realistic case, the vertical welding of thick plates free to move one against the other, is described and the deformations and stresses are analyzed. The mathematical model UEDA, which accounts for the elastic modulus, the yield strength and the expansion coefficient of the metal with temperature, is presented. The hypotheses and results given apply only to the instantaneous welding of a welded plate and to a plate welded by a moving electrode [fr

  18. EarthN: A new Earth System Nitrogen Model

    OpenAIRE

    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...

  19. Immersive Earth: Teaching Earth and Space with inexpensive immersive technology

    Science.gov (United States)

    Reiff, P. H.; Sumners, C.; Law, C. C.; Handron, K.

    2003-12-01

    In 1995 we pioneered "Space Update", the Digital Library for the rest of us", software that was so simple that a child could use it without a keyboard and yet would allow one-click updating of the daily earth and space science images without the dangers of having an open web browser on display. Thanks to NASA support, it allowed museums and schools to have a powerful exhibit for a tiny price. Over 40,000 disks in our series have been distributed so far to educators and the public. In 2003, with our partners we are again revolutionizing educational technology with a low-cost hardware and software solution to creating and displaying immersive content. Recently selected for funding as part of the REASoN competition, Immersive Earth is a partnership of scientists, museums, educators, and content providers. The hardware consists of a modest projector with a special fisheye lens to be used in an inflatable dome which many schools already have. This, coupled with a modest personal computer, can now easily project images and movies of earth and space, allows training students in 3-D content at a tiny fraction of the cost of a cave or fullscale dome theater. Another low-cost solution is the "Imove" system, where spherical movies can play on a personal computer, with the user changing the viewing direction with a joystick. We were the first to create immersive earth science shows, remain the leader in creating educational content that people want to see. We encourage people with "allsky" images or movies to bring it and see what it looks like inside a dome! Your content could be in our next show!

  20. Oxidative Stress in BPH.

    Science.gov (United States)

    Savas, M; Verit, A; Ciftci, H; Yeni, E; Aktan, E; Topal, U; Erel, O

    2009-01-01

    In the present study, we investigated the relationship between potency of oxidative stress and BPH and this may assist to contribute to the realistic explanation of the ethiopathogenesis of BPH. Seventy four newly diagnosed men with BPH (mean age: 54+/-11.2), who had not undergone any previous treatment for BPH, and 62 healthy volunteers (mean age: 55+/-14) were enrolled in the present study. To determine the antioxidative status of plasma, total antioxidant capacity (TAC) was calculated, and to determine the oxidative status of plasma (TOS) total peroxide levels were measured. The ratio of TAC to total peroxide was accepted as an indicator of oxidative stress (OSI). Data are presented as mean SD +/- unless specified. Student t-test and correlation analyses were used to evaluate the statistical significance differences in the median values recorded for all parameters between BPH and control group. Plasma TAC TOS were found in patients and controls (1.70 +/- 0.32, 1.68 +/- 0.19 micromol Trolox Equiv./L), (12.48 +/- 1.98, 12.40 +/- 1.14 micromol / L) respectively. OSI was calculated as 7.57 +/- 1.91, 7.48 +/- 1.33, respectively. Plasma TAC, TOS and OSI levels were not found to be significantly difference between patients and control subjects (p>0.05, p>0.05, p>0.05). The present study has shown that there were not relationship between potency of oxidative stress and BPH. Further well designed studies should be planned to find out whether the oxidative stress-related parameters play role in BPH as an interesting pathology in regard of the etiopathogenesis.