UV Habitable Zones Further Constrain Possible Life

NASA Astrophysics Data System (ADS)

Kohler, Susanna

2017-02-01

Where should we search for life in the universe? Habitable zones are traditionallydetermined based on the possibility of liquid water existing on a planet but ultraviolet (UV) radiation also plays a key role.The UV Habitable ZoneSchematic showing how the traditional habitable zones location and width changes around different types of stars. The UV habitable zone also hasdifferent locations and widths depending on the mass and metallicity of the star. [NASA/Kepler Mission/Dana Berry]Besides the presence of liquid water, there are other things life may need to persist. For life as we know it, one important elementis moderate UV radiation: if a planet receives too little UV flux, many biological compounds cant be synthesized. If it receives too much, however, then terrestrial biological systems (e.g. DNA) can be damaged.To determinethe most likely place to findpersistent life, we should therefore look for the region where a stars traditional habitable zone, within which liquid water is possible, overlaps with its UV habitable zone, within which the UV flux is at the right level to support life.Relationship between the stellar mass and location of the boundaries of the traditional and UV habitable zones for a solar-metallicity star. din and dout denote inner and outer boundaries, respectively. ZAMS and TMS denote when the star joins and leaves the main sequence, respectively. The traditional and UV habitable zones overlap only for stars of 11.5 solar masses. [Adapted from Oishi and Kamaya 2016]Looking for OverlapIn a recent study, two scientists from the National Defense Academy of Japan, Midori Oishi and Hideyuki Kamaya, explored howthe location of this UV habitable zone and that of its overlap with the traditional habitable zone might be affected by a stars mass and metallicity.Oishi and Kamaya developed a simple evolutional model of the UV habitable zone in stars in the mass range of 0.084 solar masses with metallicities of roughly solar metallicity (Z=0.02), a tenth of solar metallicity, and a hundredth of solar metallicity.They calculate the location of the inner and outer UV habitable zone boundaries for each star at the beginning and end of its main-sequence life. They then determine the region for which the UV habitable zone and the traditional habitable zone overlap which maximizes the potential to support persistent life.The Field NarrowsRelationship between the stellar mass and location of the boundaries of the traditional and UV habitable zones for a star of one hundredth solar metallicity. The traditional and UV habitable zones do not overlap for stars of any mass. [Adapted from Oishi and Kamaya 2016]Oishi and Kamaya find that taking the UV habitable zone into account unsurprisingly decreases the places where persistent life might be found. For solar-metallicity stars, for instance, only those stars between 1.01.5 solar masses even have overlapping traditional and UV habitable zones.As metallicity of the host star decreases, the overlapping regions decrease as well: at a metallicity of one hundredth that of the Sun (Z=0.0002), the UV and traditional habitable zones do not overlap for any mass star.The authors point out that this does not necessarily mean that such stars cant support life. Stellar activity such as flares and coronal mass ejections can temporarily increase UV flux, possibly providing enough to make up for low steady-state flux. And oceans on planetary surfaces could shield potential life from UV flux that is too high.Nonetheless, the estimates of the UV habitable zone in this study help us to narrow down the most probableplaces for findinglife in the universe.CitationMidori Oishi and Hideyuki Kamaya 2016 ApJ 833 293. doi:10.3847/1538-4357/833/2/293

The Ecological Life Zones of Puerto Rico and the U.S. Virgin Islands

Treesearch

J.J. Ewel; J.L. Whitmore

1973-01-01

Most of the neotropical nations except Mexico and Brazil are mapped according to the Moldridge system of ecological life zones. In order to have comparability with these areas, Puerto Rico and the U.S. Virgin Islands were mapped and a discussion and a description of each life zone were written. The manuscript in English offers water balances, a description of the...

75 FR 52463 - Safety Zone; Raccoon Creek, Bridgeport, NJ

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-26

... comment period would be contrary to the rule's objectives of ensuring safety of life on the navigable... required. This rule involves a limited-in-duration safety zone intended to protect life and property on the...-AA00 Safety Zone; Raccoon Creek, Bridgeport, NJ AGENCY: Coast Guard, DHS. ACTION: Temporary final rule...

Size-selective mortality of steelhead during freshwater and marine life stages related to freshwater growth in the Skagit River, Washington

USGS Publications Warehouse

Thompson, Jamie N.; Beauchamp, David A.

2014-01-01

We evaluated freshwater growth and survival from juvenile (ages 0–3) to smolt (ages 1–5) and adult stages in wild steelhead Oncorhynchus mykiss sampled in different precipitation zones of the Skagit River basin, Washington. Our objectives were to determine whether significant size-selective mortality (SSM) in steelhead could be detected between early and later freshwater stages and between each of these freshwater stages and returning adults and, if so, how SSM varied between these life stages and mixed and snow precipitation zones. Scale-based size-at-annulus comparisons indicated that steelhead in the snow zone were significantly larger at annulus 1 than those in the mixed rain–snow zone. Size at annuli 2 and 3 did not differ between precipitation zones, and we found no precipitation zone × life stage interaction effect on size at annulus. Significant freshwater and marine SSM was evident between the juvenile and adult samples at annulus 1 and between each life stage at annuli 2 and 3. Rapid growth between the final freshwater annulus and the smolt migration did not improve survival to adulthood; rather, it appears that survival in the marine environment may be driven by an overall higher growth rate set earlier in life, which results in a larger size at smolt migration. Efforts for recovery of threatened Puget Sound steelhead could benefit by considering that SSM between freshwater and marine life stages can be partially attributed to growth attained in freshwater habitats and by identifying those factors that limit growth during early life stages.

The Possibility of Multiple Habitable Worlds Orbiting Binary Stars

NASA Astrophysics Data System (ADS)

Mason, P. A.

2014-03-01

Are there planetary systems for which there is life on multiple worlds? Where are these fruitful planetary systems and how do we detect them? In order to address these questions; conditions which enable life and those that prevent or destroy it must be considered. Many constraints are specific to planetary systems, independent of the number of worlds in habitable zones. For instance, life on rocky planets or moons likely requires the right abundance of volatiles and radiogenic elements for prolonged geologic activity. Catastrophic sterilization events such as nearby supernovae and gamma-ray bursts affect entire planetary systems not just specific worlds. Giant planets may either enhance or disrupt the development of complex life within a given system. It might be rare for planetary systems to possess qualities that promote life and lucky enough to avoid cataclysm. However, multiple habitable planets may provide enhanced chances for advanced life to develop. The best predictor of life on one habitable zone planet might be the presence of life on its neighbor as panspermia may occur in planetary systems with several habitable worlds. Circumbinary habitability may go hand in hand with habitability of multiple worlds. The circumstances in which the Binary Habitability Mechanism (BHM) operates are reviewed. In some cases, the early synchronization of the primary's rotation with the binary period results in a reduction of XUV flux and stellar winds. Main sequence binaries with periods in the 10-50 days provide excellent habitable environments, within which multiple worlds may thrive. Planets and moons in these habitable zones need less magnetic protection than their single star counterparts. Exomoons orbiting a Neptune-like planet, within a BHM protected habitable zone, are expected to be habitable over a wide range of semimajor axes due to a larger planetary Hill radius. A result confirmed by numerical orbital calculations. Binaries containing a solar type star with a lower mass companion provide enhanced habitable zones as well as improved photosynthetic flux for habitable zone worlds.

From climate models to planetary habitability: temperature constraints for complex life

NASA Astrophysics Data System (ADS)

Silva, Laura; Vladilo, Giovanni; Schulte, Patricia M.; Murante, Giuseppe; Provenzale, Antonello

2017-07-01

In an effort to derive temperature-based criteria of habitability for multicellular life, we investigated the thermal limits of terrestrial poikilotherms, i.e. organisms whose body temperature and the functioning of all vital processes is directly affected by the ambient temperature. Multicellular poikilotherms are the most common and evolutionarily ancient form of complex life on earth. The thermal limits for the active metabolism and reproduction of multicellular poikilotherms on earth are approximately bracketed by the temperature interval 0°C <= T <= 50°C. The same interval applies to the photosynthetic production of oxygen, an essential ingredient of complex life, and for the generation of atmospheric biosignatures observable in exoplanets. Analysis of the main mechanisms responsible for the thermal thresholds of terrestrial life suggests that the same mechanisms would apply to other forms of chemical life. We therefore propose a habitability index for complex life, h 050, representing the mean orbital fraction of planetary surface that satisfies the temperature limits 0°C <= T <= 50°C. With the aid of a climate model tailored for the calculation of the surface temperature of Earth-like planets, we calculated h 050 as a function of planet insolation, S, and atmospheric columnar mass, N atm, for a few earth-like atmospheric compositions with trace levels of CO2. By displaying h 050 as a function of S and N atm, we built up an atmospheric mass habitable zone (AMHZ) for complex life. At variance with the classic habitable zone, the inner edge of the complex life habitable zone is not affected by the uncertainties inherent to the calculation of the runaway greenhouse limit. The complex life habitable zone is significantly narrower than the habitable zone of dry planets. Our calculations illustrate how changes in ambient conditions dependent on S and N atm, such as temperature excursions and surface dose of secondary particles of cosmic rays, may influence the type of life potentially present at different epochs of planetary evolution inside the AMHZ.

Using trading zones and life cycle analysis to understand nanotechnology regulation.

PubMed

Wardak, Ahson; Gorman, Michael E

2006-01-01

This article reviews the public health and environmental regulations applicable to nanotechnology using a life cycle model from basic research through end-of-life for products. Given nanotechnology's immense promise and public investment, regulations are important, balancing risk with the public good. Trading zones and earth systems engineering management assist in explaining potential solutions to gaps in an otherwise complex, overlapping regulatory system.

The Use of a Geographic Information System and Remote Sensing Technology for Monitoring Land Use and Soil Carbon Change in the Subtropical Dry Forest Life Zone of Puerto Rico

NASA Technical Reports Server (NTRS)

Velez-Rodriguez, Linda L. (Principal Investigator)

1996-01-01

Aerial photography, one of the first form of remote sensing technology, has long been an invaluable means to monitor activities and conditions at the Earth's surface. Geographic Information Systems or GIS is the use of computers in showing and manipulating spatial data. This report will present the use of geographic information systems and remote sensing technology for monitoring land use and soil carbon change in the subtropical dry forest life zone of Puerto Rico. This research included the south of Puerto Rico that belongs to the subtropical dry forest life zone. The Guanica Commonwealth Forest Biosphere Reserve and the Jobos Bay National Estuarine Research Reserve are studied in detail, because of their location in the subtropical dry forest life zone. Aerial photography, digital multispectral imagery, soil samples, soil survey maps, field inspections, and differential global positioning system (DGPS) observations were used.

Creep Deformation and Rupture Behavior of Single- and Dual-Pass 316LN Stainless-Steel-Activated TIG Weld Joints

NASA Astrophysics Data System (ADS)

Vijayanand, V. D.; Vasudevan, M.; Ganesan, V.; Parameswaran, P.; Laha, K.; Bhaduri, A. K.

2016-06-01

Creep deformation and rupture behavior of single-pass and dual-pass 316LN stainless steel (SS) weld joints fabricated by an autogenous activated tungsten inert gas welding process have been assessed by performing metallography, hardness, and conventional and impression creep tests. The fusion zone of the single-pass joint consisted of columnar zones adjacent to base metals with a central equiaxed zone, which have been modified extensively by the thermal cycle of the second pass in the dual-pass joint. The equiaxed zone in the single-pass joint, as well as in the second pass of the dual-pass joint, displayed the lowest hardness in the joints. In the dual-pass joint, the equiaxed zone of the first pass had hardness comparable to the columnar zone. The hardness variations in the joints influenced the creep deformation. The equiaxed and columnar zone in the first pass of the dual-pass joint was more creep resistant than that of the second pass. Both joints possessed lower creep rupture life than the base metal. However, the creep rupture life of the dual-pass joint was about twofolds more than that of the single-pass joint. Creep failure in the single-pass joint occurred in the central equiaxed fusion zone, whereas creep cavitation that originated in the second pass was blocked at the weld pass interface. The additional interface and strength variation between two passes in the dual-pass joint provides more restraint to creep deformation and crack propagation in the fusion zone, resulting in an increase in the creep rupture life of the dual-pass joint over the single-pass joint. Furthermore, the differences in content, morphology, and distribution of delta ferrite in the fusion zone of the joints favors more creep cavitation resistance in the dual-pass joint over the single-pass joint with the enhancement of creep rupture life.

77 FR 30245 - Safety Zones; Annual Fireworks Events in the Captain of the Port Detroit Zone

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-22

...-AA00 Safety Zones; Annual Fireworks Events in the Captain of the Port Detroit Zone AGENCY: Coast Guard... by adding three permanent safety zones within the Captain of the Port Detroit Zone. This action is necessary to provide for the safety of life and property on navigable waters during each event. This action...

77 FR 64943 - Security Zone, Potomac and Anacostia Rivers; Washington, DC

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-24

... the ability to implement comprehensive port security regimes designed to safeguard human life, vessels... communities would have. The proposed security zone is necessary to safeguard life and property on the... cumulatively have a significant effect on the human environment. This proposed rule involves establishing a...

40 CFR 63.1365 - Test methods and initial compliance procedures.

Code of Federal Regulations, 2013 CFR

2013-07-01

... design minimum and average temperature in the combustion zone and the combustion zone residence time. (B... establish the design minimum and average flame zone temperatures and combustion zone residence time, and... carbon bed temperature after regeneration, design carbon bed regeneration time, and design service life...

Life prediction and constitutive models for engine hot section anisotropic materials program

NASA Technical Reports Server (NTRS)

Nissley, D. M.; Meyer, T. G.; Walker, K. P.

1992-01-01

This report presents a summary of results from a 7 year program designed to develop generic constitutive and life prediction approaches and models for nickel-based single crystal gas turbine airfoils. The program was composed of a base program and an optional program. The base program addressed the high temperature coated single crystal regime above the airfoil root platform. The optional program investigated the low temperature uncoated single crystal regime below the airfoil root platform including the notched conditions of the airfoil attachment. Both base and option programs involved experimental and analytical efforts. Results from uniaxial constitutive and fatigue life experiments of coated and uncoated PWA 1480 single crystal material formed the basis for the analytical modeling effort. Four single crystal primary orientations were used in the experiments: group of zone axes (001), group of zone axes (011), group of zone axes (111), and group of zone axes (213). Specific secondary orientations were also selected for the notched experiments in the optional program. Constitutive models for an overlay coating and PWA 1480 single crystal materials were developed based on isothermal hysteresis loop data and verified using thermomechanical (TMF) hysteresis loop data. A fatigue life approach and life models were developed for TMF crack initiation of coated PWA 1480. A life model was developed for smooth and notched fatigue in the option program. Finally, computer software incorporating the overlay coating and PWA 1480 constitutive and life models was developed.

Europa, tidally heated oceans, and habitable zones around giant planets

NASA Astrophysics Data System (ADS)

Reynolds, R. T.; McKay, C. P.; Kasting, J. F.

Tidal dissipation in the satellites of a giant planet may provide sufficient heating to maintain an environment favorable to life on the satellite surface or just below a thin ice layer. Europa could have a liquid ocean which may occasionally receive sunlight through cracks in the overlying ice shell. In such a case, sufficient solar energy could reach liquid water that organisms similar to those found under Antarctic ice could grow. In other solar systems, larger satellites with more significant heat flow could represent environments that are stable over an order of eons and in which life could perhaps evolve. A zone around a giant planet is defined in which such satellites could exist as a tidally-heated habitable zone. This zone can be compared to the habitable zone which results from heating due to the radiation of a central star. In this solar system, this radiatively-heated habitable zone contains the earth.

Europa, tidally heated oceans, and habitable zones around giant planets

NASA Technical Reports Server (NTRS)

Reynolds, Ray T.; Mckay, Christopher P.; Kasting, James F.

1987-01-01

Tidal dissipation in the satellites of a giant planet may provide sufficient heating to maintain an environment favorable to life on the satellite surface or just below a thin ice layer. Europa could have a liquid ocean which may occasionally receive sunlight through cracks in the overlying ice shell. In such a case, sufficient solar energy could reach liquid water that organisms similar to those found under Antarctic ice could grow. In other solar systems, larger satellites with more significant heat flow could represent environments that are stable over an order of eons and in which life could perhaps evolve. A zone around a giant planet is defined in which such satellites could exist as a tidally-heated habitable zone. This zone can be compared to the habitable zone which results from heating due to the radiation of a central star. In this solar system, this radiatively-heated habitable zone contains the earth.

Life zone investigations in Wyoming

USGS Publications Warehouse

Cary, Merritt

1917-01-01

Wyoming is among the foremost of our States in its wealth of natural scenery, culminating in the grandeur of Yellowstone National Park, one of the wonders of the world. In addition to this distinction it posseses vast open plains and lofty mountains whence flow the headwaters of mighty river systems emptying far away to the west into the Pacific Ocean, to the southeast into the Gulf of Mexico, and to the southwest into the Gulf of California. The various slope exposures of its mountain ranges, the fertility of its intervening valleys or basins, and the aridity of its desert spaces present a study of geographic and vertical distribution of wild life that is in many particulars unique.The study of geographic and vertical distribution of life with the governing factors and attendant problems is valuable as a matter of scientific research and in the attainment of practical knowledge. The Biological Survey has been making detailed investigations of the transcontinental life belts, or zones, of North America for some years, and this work has been carried on with special reference to their practical value. It has become increasingly evident that life zones furnish a fairly accurate index to average climatic conditions and, therefore, are useful as marking the limits of agricultural possibilities, so far as these are dependent upon climate. The knowledge thus gained has been published and made available as the investigations have progressed and the life zones have been mapped.1

Novelty and its ecological implications to dry forest functioning and conservation

Treesearch

Ariel Lugo; Heather Erickson

2017-01-01

Tropical and subtropical dry forest life zones support forests with lower stature and species richness than do tropical and subtropical life zones with greater water availability. The number of naturalized species that can thrive and mix with native species to form novel forests in dry forest conditions in Puerto Rico and the US Virgin Islands is lower than in other...

Can we manage tropical landscapes? – an answer from the Caribbean perspective.

Treesearch

Ariel E. Lugo

2002-01-01

Humans have used Caribbean island landscapes for millennia. The conversion of wild lands to built-up lands or to agricultural lands in these tropical countries follows predictable patterns. Conversion of moist forest life zones and fertile flatlands is faster than conversion of wet and rain forest life zones and low fertility steep lands. In Puerto Rico, these trends...

Europa, tidally heated oceans, and habitable zones around giant planets.

PubMed

Reynolds, R T; McKay, C P; Kasting, J F

1987-01-01

Tidal dissipation in the satellites of a giant planet may provide sufficient heating to maintain an environment favorable to life on the satellite surface or just below a thin ice layer. In our own solar system, Europa, one of the Galilean satellites of Jupiter, could have a liquid ocean which may occasionally receive sunlight through cracks in the overlying ice shell. In such case, sufficient solar energy could reach liquid water that organisms similar to those found under Antarctic ice could grow. In other solar systems, larger satellites with more significant heat flow could represent environments that are stable over an order of Aeons and in which life could perhaps evolve. We define a zone around a giant planet in which such satellites could exist as a tidally-heated habitable zone. This zone can be compared to the habitable zone which results from heating due to the radiation of a central star. In our solar system, this radiatively-heated habitable zone contains the Earth.

78 FR 7670 - Safety Zone; Indian Street Bridge Construction, St. Lucie Canal, Palm City, FL

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-04

... 1625-AA00 Safety Zone; Indian Street Bridge Construction, St. Lucie Canal, Palm City, FL AGENCY: Coast... zone on the St. Lucie Canal, Palm City, Florida to provide for the safety of life and vessels on a... on a narrow waterway. The temporary safety zone encompasses all waters of the St. Lucie Canal in the...

76 FR 43124 - Safety Zones; July Fireworks Displays and Swim Events in the Captain of the Port New York Zone

Federal Register 2010, 2011, 2012, 2013, 2014

2011-07-20

... York Zone AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is... safety of life on navigable waters during the events. Entry into, transit through, mooring or anchoring within these zones is prohibited unless authorized by the COTP New York. DATES: This rule is effective...

Fiber Laser Welded AZ31 Magnesium Alloy: The Effect of Welding Speed on Microstructure and Mechanical Properties

NASA Astrophysics Data System (ADS)

Chowdhury, S. H.; Chen, D. L.; Bhole, S. D.; Powidajko, E.; Weckman, D. C.; Zhou, Y.

2012-06-01

This study was aimed at characterizing microstructural change and evaluating tensile and fatigue properties of fiber laser welded AZ31B-H24 Mg alloy with special attention to the effect of welding speed. Laser welding led to the formation of equiaxed dendrites in the fusion zone and columnar dendrites near the fusion zone boundary along with divorced eutectic Mg17Al12 particles and recrystallized grains in the heat-affected zone. The lowest hardness across the weld appeared in the fusion zone. Although the yield strength, ductility, and fatigue life decreased, the hardening capacity increased after laser welding, with a joint efficiency reaching about 90 pct. A higher welding speed resulted in a narrower fusion zone, smaller grain size, higher yield strength, and longer fatigue life, as well as a slightly lower strain-hardening capacity mainly because of the smaller grain sizes. Tensile fracture occurred in the fusion zone, whereas fatigue failure appeared essentially in between the heat-affected zone and the fusion zone. Fatigue cracks initiated from the near-surface welding defects and propagated by the formation of fatigue striations together with secondary cracks.

Probabalistic Risk Assessment of a Turbine Disk

NASA Astrophysics Data System (ADS)

Carter, Jace A.; Thomas, Michael; Goswami, Tarun; Fecke, Ted

Current Federal Aviation Administration (FAA) rotor design certification practices risk assessment using a probabilistic framework focused on only the life-limiting defect location of a component. This method generates conservative approximations of the operational risk. The first section of this article covers a discretization method, which allows for a transition from this relative risk to an absolute risk where the component is discretized into regions called zones. General guidelines were established for the zone-refinement process based on the stress gradient topology in order to reach risk convergence. The second section covers a risk assessment method for predicting the total fatigue life due to fatigue induced damage. The total fatigue life incorporates a dual mechanism approach including the crack initiation life and propagation life while simultaneously determining the associated initial flaw sizes. A microstructure-based model was employed to address uncertainties in material response and relate crack initiation life with crack size, while propagation life was characterized large crack growth laws. The two proposed methods were applied to a representative Inconel 718 turbine disk. The zone-based method reduces the conservative approaches, while showing effects of feature-based inspection on the risk assessment. In the fatigue damage assessment, the predicted initial crack distribution was found to be the most sensitive probabilistic parameter and can be used to establish an enhanced inspection planning.

Potential Habitats for Exotic Life Within the Life Supporting Zone

NASA Astrophysics Data System (ADS)

Leitner, Johannes J.; Firneis, Maria G.; Hitzenberger, Regina

2010-05-01

Questions like "Are we alone in the universe?", "How unique is Earth as a planet?" or "How unique is water-based life in the universe?" still are nowhere near of being answered. In recent years, discussions on these topics are more and more influenced by questions whether water is really the only possible solvent, or which conditions are necessary for life to evolve in planetary habitats. A change in our present geocentric mindset on the existence of life is required, in order to address these new questions [see also 1]. In May 2009 a new research platform at the University of Vienna was initiated in order to contribute to the solution of these questions. One task is to find essential biomarkers relevant to the problem of the detection of exotic life. In this context exotic life means: life, which is not necessarily based on a double bond between carbon and oxygen (C=O) and not on water as the only possible solvent. At present little is known about metabolistic systems, which are not based on C=O or on metabolisms which are operative in alternative solvents and a high effort of future laboratory work is necessary to open this window for looking for exotic life. To address the whole spectrum of life the concept of a general life supporting zone is introduced in order to extend the classical habitable zone (which is based on liquid water on a planetary surface, [2]). The life supporting zone of a planetary system is composed of different single "habitable zones" for the liquid phases of specific solvents and composites between water and other solvents. Besides exoplanetary systems which seem to be the most promising place for exotic life in our present understanding, some potential places could also exist within our Solar System and habitats like the subsurface of Enceladus, liquid ethane/methane lakes on Titan or habitable niches in the Venus atmosphere will also be taken into account. A preliminary list of appropriate solvents and their abundances in the Solar System and beyond have been compiled. Dynamical investigations (related to the interior of superearths), but also heat transport regimes and potential cycles with exotic solvents as well as tidal heating processes and their influence on the thermal regime of the planets will help to define the regions of potential exotic life more precisely. Atmospheric and subsurface cycles which can take place in such habitats as well as cloud and droplet formation with and without cloud nuclei cores will further extend our knowledge on mechanisms relevant for the stability of these systems. Finally the question of suitable biomarkers, which can enable the observation of exotic habitats and their potential life forms will be considered in the research platform. In this context a special topic is also the bandwidth of photosynthesis: how is the influence of different atmospheric gases and what are the environment conditions for the chemical reactions of photosynthesis? First preliminary results for the life supporting zones of selected planetary systems will be presented. References: [1] NRC (National Research Council)(2007) The Limits of Organic Life in Planetary Systems, National Academies Press, Washington, DC 20001, ISBN 978-0-309-10484-5. [2] Kasting, J.F., Whitmore D.P. and Reynolds R.T. (1993) Icarus, 101, 109-128.

[Research advances in macroinvertebrate ecology of the stream hyporheic zone].

PubMed

Zhang, Yue-Wei; Yuan, Xing-Zhong; Liu, Hong; Ren, Hai-Qing

2014-11-01

The stream hyporheic zone is an ecotone of surface water-ground water interactions, which is rich in biodiversity, and is an important component of stream ecosystem. The macroinvertebrates, which are at the top of food webs in the hyporheic zone to directly influence the matter and energy dynamics of the hyporheic zone, and are potential indicators of river ecological health to adjust the function of environment purification and ecological buffer. The macroinvertebrates in the hyporheic zone are divided into three categories: stygoxenes, stygophiles and stygobites. The key factors which influenced macroinvertebrates distribution in the hyporheic zone are physical size of interstitial spaces, interstitial current velocity, dissolved oxygen (DO), water temperature, available organic matter, hydraulic conductivity and hydraulic retention time. A suitable sampling method should be used for diverse research purposes in the special ecological interface. In the future, some necessary researches should focus on the life-history and life history strategy of the macroinvertebrates in the hyporheic zone, the quantitative analysis on the matter and energy dynamics in the ecological system of stream, the assessment systems of river ecological health based on the macroinvertebrates of the stream hyporheic zone, and the ecological significance of the hyporheic zone as a refuge for distribution and evolution of the macroinvertebrates.

Age aspects of habitability

NASA Astrophysics Data System (ADS)

Safonova, M.; Murthy, J.; Shchekinov, Yu. A.

2016-04-01

A `habitable zone' of a star is defined as a range of orbits within which a rocky planet can support liquid water on its surface. The most intriguing question driving the search for habitable planets is whether they host life. But is the age of the planet important for its habitability? If we define habitability as the ability of a planet to beget life, then probably it is not. After all, life on Earth has developed within only ~800 Myr after its formation - the carbon isotope change detected in the oldest rocks indicates the existence of already active life at least 3.8 Gyr ago. If, however, we define habitability as our ability to detect life on the surface of exoplanets, then age becomes a crucial parameter. Only after life had evolved sufficiently complex to change its environment on a planetary scale, can we detect it remotely through its imprint on the atmosphere - the so-called biosignatures, out of which the photosynthetic oxygen is the most prominent indicator of developed (complex) life as we know it. Thus, photosynthesis is a powerful biogenic engine that is known to have changed our planet's global atmospheric properties. The importance of planetary age for the detectability of life as we know it follows from the fact that this primary process, photosynthesis, is endothermic with an activation energy higher than temperatures in habitable zones, and is sensitive to the particular thermal conditions of the planet. Therefore, the onset of photosynthesis on planets in habitable zones may take much longer time than the planetary age. The knowledge of the age of a planet is necessary for developing a strategy to search for exoplanets carrying complex (developed) life - many confirmed potentially habitable planets are too young (orbiting Population I stars) and may not have had enough time to develop and/or sustain detectable life. In the last decade, many planets orbiting old (9-13 Gyr) metal-poor Population II stars have been discovered. Such planets had had enough time to develop necessary chains of chemical reactions and may carry detectable life if located in a habitable zone. These old planets should be primary targets in search for the extraterrestrial life.

The Drake Equation revisited

NASA Astrophysics Data System (ADS)

Konesky, Gregory

2009-08-01

In the almost half century since the Drake Equation was first conceived, a number of profound discoveries have been made that require each of the seven variables of this equation to be reconsidered. The discovery of hydrothermal vents on the ocean floor, for example, as well as the ever-increasing extreme conditions in which life is found on Earth, suggest a much wider range of possible extraterrestrial habitats. The growing consensus that life originated very early in Earth's history also supports this suggestion. The discovery of exoplanets with a wide range of host star types, and attendant habitable zones, suggests that life may be possible in planetary systems with stars quite unlike our Sun. Stellar evolution also plays an important part in that habitable zones are mobile. The increasing brightness of our Sun over the next few billion years, will place the Earth well outside the present habitable zone, but will then encompass Mars, giving rise to the notion that some Drake Equation variables, such as the fraction of planets on which life emerges, may have multiple values.

Life cycle strategies of copepods in coastal upwelling zones

NASA Astrophysics Data System (ADS)

Peterson, W.

1998-06-01

Life cycles of copepods of coastal upwelling zones are of the multigenerational type—as many as 10 or more generations may be produced each year, depending upon water temperature, food concentration and length of the upwelling season. Abundant food resources and moderate temperature convey advantages to those copepods living in coastal upwelling zones, however, there is a clear disadvantage in that coastal upwelling zones are highly advective environments. Typically, water circulation patterns are such that surface waters are carried offshore, deeper waters carried onshore and most of the water column over the continental shelf is moving equatorward. The challenge to copepod species that inhabit upwelling systems is life cycle closure—how do eggs, nauplii, juveniles and adults avoid being swept out of these ecosystems in the face of persistent transport out of the system? In this review, I first list the species which dominate coastal upwelling ecosystems then discuss three variations on the multigenerational life cycle scheme that are observed in upwelling systems. The latter part of the review is devoted to discussion of how individuals are retained in the productive continental shelf waters within coastal upwelling ecosystems. The suggestion is made that the only copepod species that successfully achieve life cycle closure in such systems are those that are preadapted to upwelling circulation patterns. Our quantitative understanding of the relative importance of physical factors (such as advection) and biological factors (birth, growth, and mortality) on life cycle strategies and population dynamics is quite rudimentary. It would help our understanding if there were more field studies and more computer modeling studies that focused on seasonal cycles of abundance, development times and vertical distribution of life cycle stages, and measurements of water circulation patterns.

Can France Give Education Action Zones New Life?

ERIC Educational Resources Information Center

Storey, Valerie A.

2007-01-01

Schools are essentially expected to provide all students with the same educational opportunity despite where they live, or their ability levels. Education Action Zones (EAZs) and Zones d'Education Prioritaire (ZEPs) have been implemented to help eradicate the issue of student equity, promising innovation and a solution to inequalities evidenced in…

77 FR 27116 - Safety Zone, Naval Helicopter Association Reunion Helicopter Demonstration, Elizabeth River...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-09

...-AA00 Safety Zone, Naval Helicopter Association Reunion Helicopter Demonstration, Elizabeth River... establishing a temporary safety zone on the Elizabeth River in the vicinity of Norfolk, VA to support the Naval... of life on navigable waters during the Naval Helicopter Association Reunion Helicopter Demonstration...

International Space Station (ISS) Node 1 Environmental Control and Life Support (ECLS) System Keep Out Zone On-Orbit Problems

NASA Technical Reports Server (NTRS)

Williams, David E.

2004-01-01

The International Space Station (ISS) Environmental Control and Life Support (ECLS) system performance can be impacted by operations on ISS. This is especially important for the Temperature and Humidity Control (THC) and for the Fire Detection and Suppression (FDS) subsystems. It is also more important for Node 1 since it has become a convenient area for many crew tasks and for stowing hardware prior to Shuttle arrival. This paper will discuss the current requirements for ECLS keep out zones in Node 1; the issues with stowage in Node 1 during Increment 7 and how they impacted the keep out zone requirements; and the solution during Increment 7 and 8 for maintaining the keep out zones in Node 1.

Latitude of residence and position in time zone are predictors of cancer incidence, cancer mortality, and life expectancy at birth.

PubMed

Borisenkov, Mikhail F

2011-03-01

According to the hypothesis of circadian disruption, external factors that disturb the function of the circadian system can raise the risk of malignant neoplasm and reduce life span. Recent work has shown that the functionality of the circadian system is dependent not only on latitude of residence but also on the region's position in the time zone. The purpose of the present research was to examine the influence of latitude and time zone on cancer incidence, cancer mortality, and life expectancy at birth. A stepwise multiple regression analysis was carried out on residents of 59 regions of the European part of the Russian Federation (EPRF) using age-standardized parameters (per 100,000) of cancer incidence (CI), cancer mortality (CM), and life expectancy at birth (LE, yrs) as dependent variables. The geographical coordinates (latitude and position in the time zone) of the regions were used as independent variables, controlling for the level of economic development in the regions. The same analysis was carried out for LE in 31 regions in China. Latitude was the strongest predictor of LE in the EPRF population; it explained 48% and 45% of the variability in LE of women and men, respectively. Position within the time zone accounted for an additional 4% and 3% variability of LE in women and men, respectively. The highest values for LE were observed in the southeast of the EPRF. In China, latitude was not a predictor of LE, whereas position in the time zone explained 15% and 18% of the LE variability in women and men, respectively. The highest values of LE were observed in the eastern regions of China. Both latitude and position within the time zone were predictors for CI and CM of the EPRF population. Latitude was the best predictor of stomach CI and CM; this predictor explained 46% and 50% of the variability, respectively. Position within the time zone was the best predictor of female breast CM; it explained 15% of the variability. In most cases, CI and CM increased with increasing latitude of residence, from the eastern to the western border of the time zone, and with increasing level of economic development within the region. The dependence of CI, CM, and LE on the geographical coordinates of residence is in agreement with the hypothesis of circadian disruption.

Field-scale forward and back diffusion through low-permeability zones

NASA Astrophysics Data System (ADS)

Yang, Minjune; Annable, Michael D.; Jawitz, James W.

2017-07-01

Understanding the effects of back diffusion of groundwater contaminants from low-permeability zones to aquifers is critical to making site management decisions related to remedial actions. Here, we combine aquifer and aquitard data to develop recommended site characterization strategies using a three-stage classification of plume life cycle based on the solute origins: aquifer source zone dissolution, source zone dissolution combined with back diffusion from an aquitard, and only back diffusion. We use measured aquitard concentration profile data from three field sites to identify signature shapes that are characteristic of these three stages. We find good fits to the measured data with analytical solutions that include the effects of advection and forward and back diffusion through low-permeability zones, and linearly and exponentially decreasing flux resulting from source dissolution in the aquifer. Aquifer contaminant time series data at monitoring wells from a mature site were well described using analytical solutions representing the combined case of source zone and back diffusion, while data from a site where the source had been isolated were well described solely by back diffusion. The modeling approach presented in this study is designed to enable site managers to implement appropriate remediation technologies at a proper timing for high- and low-permeability zones, considering estimated plume life cycle.

Field-scale forward and back diffusion through low-permeability zones.

PubMed

Yang, Minjune; Annable, Michael D; Jawitz, James W

2017-07-01

Understanding the effects of back diffusion of groundwater contaminants from low-permeability zones to aquifers is critical to making site management decisions related to remedial actions. Here, we combine aquifer and aquitard data to develop recommended site characterization strategies using a three-stage classification of plume life cycle based on the solute origins: aquifer source zone dissolution, source zone dissolution combined with back diffusion from an aquitard, and only back diffusion. We use measured aquitard concentration profile data from three field sites to identify signature shapes that are characteristic of these three stages. We find good fits to the measured data with analytical solutions that include the effects of advection and forward and back diffusion through low-permeability zones, and linearly and exponentially decreasing flux resulting from source dissolution in the aquifer. Aquifer contaminant time series data at monitoring wells from a mature site were well described using analytical solutions representing the combined case of source zone and back diffusion, while data from a site where the source had been isolated were well described solely by back diffusion. The modeling approach presented in this study is designed to enable site managers to implement appropriate remediation technologies at a proper timing for high- and low-permeability zones, considering estimated plume life cycle. Copyright © 2017 Elsevier B.V. All rights reserved.

78 FR 3326 - Safety Zone Within the Lower Portion of Anchorage #9, Mantua Creek Anchorage; Paulsboro, NJ

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-16

... 1625-AA00 Safety Zone Within the Lower Portion of Anchorage 9, Mantua Creek Anchorage; Paulsboro, NJ... temporary safety zone around the southern one-third of Anchorage 9 (Mantua Creek Anchorage) due to dredging... through this portion of the anchorage. This regulation is necessary to provide for the safety of life on...

78 FR 17094 - Safety Zone; 2013 Naval Air Station Key West Air Spectacular, Boca Chica Channel; Boca Chica, FL

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-20

...-AA00 Safety Zone; 2013 Naval Air Station Key West Air Spectacular, Boca Chica Channel; Boca Chica, FL... Air Station Key West Air Spectacular. The safety zone is necessary to provide for the safety of life on navigable waters during the air show and air show practices. Persons and vessels are prohibited...

33 CFR 100.T05-0443 - Safety Zone; Fireworks Display, Delaware River, New Hope, PA.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., Delaware River, New Hope, PA. 100.T05-0443 Section 100.T05-0443 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY REGATTAS AND MARINE PARADES SAFETY OF LIFE ON NAVIGABLE WATERS § 100.T05-0443 Safety Zone; Fireworks Display, Delaware River, New Hope, PA. (a) Location. The safety zone will restrict...

78 FR 48311 - Special Local Regulations; Regattas and Marine Parades in the Captain of the Port Lake Michigan Zone

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-08

... Zone AGENCY: Coast Guard, DHS. ACTION: Final rule. SUMMARY: The Coast Guard is amending special local regulations for annual regattas and marine parades in the Captain of the Port Lake Michigan Zone. This rule is intended to provide for the safety of life and property on navigable waters immediately prior to, during...

78 FR 11094 - Safety Zone; Lake Worth Dredge Operations, Lake Worth Inlet; West Palm Beach, FL

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-15

... 1625-AA00 Safety Zone; Lake Worth Dredge Operations, Lake Worth Inlet; West Palm Beach, FL AGENCY... safety zone on Lake Worth Inlet, West Palm Beach, Florida, to provide for the safety of life and vessels..., dredging operations will be conducted on Lake Worth Inlet in West Palm Beach, Florida. These operations...

76 FR 26607 - Safety Zone; Air Power Over Hampton Roads, Back River, Hampton, VA

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-09

...-AA00 Safety Zone; Air Power Over Hampton Roads, Back River, Hampton, VA AGENCY: Coast Guard, DHS... the safety of life on navigable waters during the Air Power Over Hampton Roads Air Show. This action.... This safety zone is in the interest of public safety during the Hampton Roads Air Show and will be...

78 FR 37963 - Safety Zone; Chicago to Mackinac Race; Lake Michigan; Chicago, IL

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-25

... Zone; Chicago to Mackinac Race; Lake Michigan; Chicago, IL AGENCY: Coast Guard, DHS. ACTION: Notice of..., Illinois for the 105th Race to Mackinac. This zone will be enforced from 2 p.m. until 4:30 p.m. on July 12... of life on the navigable waters during the 105th Race to Mackinac. During the aforementioned periods...

Tropical anurans mature early and die young: Evidence from eight Afromontane Hyperolius species and a meta-analysis

PubMed Central

2017-01-01

Age- and size-related life-history traits of anuran amphibians are thought to vary systematically with latitude and altitude. Because the available data base is strongly biased towards temperate-zone species, we provide new estimates on eight afrotropical Reed Frog species. A meta-analysis of the demographic traits in 44 tropical anuran species aims to test for the predicted clinal variation and to contrast results with variation detected in temperate-zone species. The small-sized reed frogs reach sexual maturity during the first or second year of life, but longevity does not exceed three to four years. Latitudinal effects on demographic life-history traits are not detectable in tropical anurans, and altitudinal effects are limited to a slight size reduction at higher elevations. Common features of anuran life-history in the tropics are early sexual maturation at small size and low longevity resulting in low lifetime fecundity. This pattern contrasts with that found in temperate-zone anurans which mature later at larger size and grow considerably older yielding greater lifetime fecundity than in the tropics. Latitudinal and altitudinal contraction of the yearly activity period shape the evolution of life-history traits in the temperate region, while trait variation in the tropics seems to be driven by distinct, not yet identified selective forces. PMID:28182738

Determining Source Attenuation History to Support Closure by Natural Attenuation

DTIC Science & Technology

2013-09-01

SUBTITLE 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 6. AUTHOR(S...Tortuosity Factor Exponent Bulk Density of Low-k Zone DistriDutlon Coemctent or FractiOn Organic Carbon In Low-k Zone o rgaric CarDon Pa-tnioning...Organic Carbon In Low-k Zone orgaric CarDon Pa-tnioning coemctent Constrtuent Half-Life in Low-k Zone 3. GEN ERA L Year Core sample Collected fran

Landscape ecological security response to land use change in the tidal flat reclamation zone, China.

PubMed

Zhang, Runsen; Pu, Lijie; Li, Jianguo; Zhang, Jing; Xu, Yan

2016-01-01

As coastal development becomes a national strategy in Eastern China, land use and landscape patterns have been affected by reclamation projects. In this study, taking Rudong County, China as a typical area, we analyzed land use change and its landscape ecological security responses in the tidal flat reclamation zone. The results show that land use change in the tidal flat reclamation zone is characterized by the replacement of natural tidal flat with agricultural and construction land, which has also led to a big change in landscape patterns. We built a landscape ecological security evaluation system, which consists of landscape interference degree and landscape fragile degree, and then calculated the landscape ecological security change in the tidal flat reclamation zone from 1990 to 2008 to depict the life cycle in tidal flat reclamation. Landscape ecological security exhibited a W-shaped periodicity, including the juvenile stage, growth stage, and maturation stage. Life-cycle analysis demonstrates that 37 years is required for the land use system to transform from a natural ecosystem to an artificial ecosystem in the tidal flat reclamation zone.

Biocybrid systems and the re-engineering of life

NASA Astrophysics Data System (ADS)

Domingues, Diana; Ferreira da Rocha, Adson; Hamdan, Camila; Augusto, Leci; Miosso, Cristiano Jacques

2011-03-01

The reengineering of life expanded by perceptual experiences in the sense of presence in Virtual Reality and Augmented Reality is the theme of our investigation in collaborative practices confirming the artistś creativity close to the inventivity of scientists and mutual capacity for the generation of biocybrid systems. We consider the enactive bodily interfaces for human existence being co-located in the continuum and symbiotic zone between body and flesh - cyberspace and data - and the hybrid properties of physical world. That continuum generates a biocybrid zone (Bio+cyber+hybrid) and the life is reinvented. Results reaffirm the creative reality of coupled body and mutual influences with environment information, enhancing James Gibson's ecological perception theory. The ecosystem life in its dynamical relations between human, animal, plants, landscapes, urban life and objects, bring questions and challenges for artworks and the reengineering of life discussed in our artworks in technoscience. Finally, we describe an implementation in which the immersion experience is enhanced by the datavisualization of biological audio signals and by using wearable miniaturized devices for biofeedback.

77 FR 32018 - Safety Zone; Kemah Boardwalk Summer Season Fireworks, Galveston Bay, Kemah, TX

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-31

... significant effect on the human environment. This rule involves the establishment of a safety zone for the protection of human life. This rule is categorically excluded from further review under paragraph 34(g) of...

75 FR 65232 - Security Zones; Sabine Bank Channel, Sabine Pass Channel and Sabine-Neches Waterway, TX

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-22

... security zones would be part of a comprehensive port security regime designed to safeguard human life... do not individually or cumulatively have a significant effect on the human environment. This rule is...

The habitable zone and extreme planetary orbits.

PubMed

Kane, Stephen R; Gelino, Dawn M

2012-10-01

The habitable zone for a given star describes the range of circumstellar distances from the star within which a planet could have liquid water on its surface, which depends upon the stellar properties. Here we describe the development of the habitable zone concept, its application to our own solar system, and its subsequent application to exoplanetary systems. We further apply this to planets in extreme eccentric orbits and show how they may still retain life-bearing properties depending upon the percentage of the total orbit which is spent within the habitable zone. Key Words: Extrasolar planets-Habitable zone-Astrobiology.

Relation between the fracture laws and the fatigue life of a surface-hardened pseudo-α titanium alloy

NASA Astrophysics Data System (ADS)

Bagmutov, V. P.; Vodop'yanov, V. I.; Zakharov, I. N.; Denisevich, D. S.

2016-07-01

The laws of fracture and fatigue life of the PT-3V pseudo-α titanium alloy subjected to surface hardening using electromechanical, ultrasonic, and combined treatment are studied. Fracture mechanisms and the structures of crack nucleation and growth zones are described using the results of metallographic and fractographic analysis of samples after fatigue tests. It is shown that the existence of a thin hardened layer on the sample surface changes the crack nucleation time and the state of fracture surface in the crack nucleation zone. This surface is characterized by signs of brittle or ductile fracture, which substantially affects the fatigue life of the sample.

Life cycles of dominant mayflies (Ephemeroptera) on a torrent of the high Bolivian Andes

PubMed

Molina, Carlos I; Puliafico, Kenneth P

2016-03-01

The mayflies of the temperate and cold zones have well-synchronized life cycles, distinct cohorts, short emergence and flight periods. In contrast, aquatic insects from the tropical zones are characterized by multivoltine life cycles, “non-discernible cohorts” and extended flight periods throughout the year. This report is the first observation of life cycle patterns made of two species of mayflies on a torrent in the high elevation Bolivian Andes. The samples were taken from four sites and four periods during a hydrological season. The life cycle of each species was examined using size-class frequency analysis and a monthly modal progression model (von Bertalanffy’s model) to infer the life cycle synchrony type. These first observations showed a moderately synchronized univoltine life cycle for Andesiops peruvianus (Ulmer, 1920), whereas Meridialaris tintinnabula Pescador and Peters (1987), had an unsynchronized multivoltine life cycle. These results showed that the generalization of all aquatic insects as unsynchronized multivoltine species in the Andean region may not be entirely accurate since there is still a need to further clarify the life cycle patterns of the wide variety of aquatic insects living in this high elevation tropical environment.

78 FR 4790 - Security Zone, Potomac and Anacostia Rivers; Washington, DC

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-23

... comprehensive port security regimes designed to safeguard human life, vessels, and waterfront facilities while... the need for immediate action, the restriction of vessel traffic is necessary to protect life... necessary to safeguard life and property on the navigable waters before, during, and after activities...

77 FR 2450 - Security Zone; Potomac and Anacostia Rivers, Washington, DC

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-18

... implement comprehensive port security regimes designed to safeguard human life, vessels, and waterfront... protect life, property and the environment, therefore, a 30-day notice period is impracticable. Delaying... enhance public and maritime safety and security in order to safeguard life, property, and the environment...

Fledgling survival increases with development time and adult survival across north and south temperate zones

USGS Publications Warehouse

Lloyd, Penn; Martin, Thomas E.

2016-01-01

Slow life histories are characterized by high adult survival and few offspring, which are thought to allow increased investment per offspring to increase juvenile survival. Consistent with this pattern, south temperate zone birds are commonly longer-lived and have fewer young than north temperate zone species. However, comparative analyses of juvenile survival, including during the first few weeks of the post-fledging period when most juvenile mortality occurs, are largely lacking. We combined our measurements of fledgling survival for eight passerines in South Africa with estimates from published studies of 57 north and south temperate zone songbird species to test three predictions: (1) fledgling survival increases with length of development time in the nest; (2) fledgling survival increases with adult survival and reduced brood size controlled for development time; and (3) south temperate zone species, with their higher adult survival and smaller brood sizes, exhibit higher fledgling survival than north temperate zone species controlled for development time. We found that fledgling survival was higher among south temperate zone species and generally increased with development time and adult survival within and between latitudinal regions. Clutch size did not explain additional variation, but was confounded with adult survival. Given the importance of age-specific mortality to life history evolution, understanding the causes of these geographical patterns of mortality is important.

S3: School Zone Safety System Based on Wireless Sensor Network

PubMed Central

Yoo, Seong-eun; Chong, Poh Kit; Kim, Daeyoung

2009-01-01

School zones are areas near schools that have lower speed limits and where illegally parked vehicles pose a threat to school children by obstructing them from the view of drivers. However, these laws are regularly flouted. Thus, we propose a novel wireless sensor network application called School zone Safety System (S3) to help regulate the speed limit and to prevent illegal parking in school zones. S3 detects illegally parked vehicles, and warns the driver and records the license plate number. To reduce the traveling speed of vehicles in a school zone, S3 measures the speed of vehicles and displays the speed to the driver via an LED display, and also captures the image of the speeding vehicle with a speed camera. We developed a state machine based vehicle detection algorithm for S3. From extensive experiments in our testbeds and data from a real school zone, it is shown that the system can detect all kinds of vehicles, and has an accuracy of over 95% for speed measurement. We modeled the battery life time of a sensor node and validated the model with a downscaled measurement; we estimate the battery life time to be over 2 years. We have deployed S3 in 15 school zones in 2007, and we have demonstrated the robustness of S3 by operating them for over 1 year. PMID:22454567

A Simple Evolutional Model of the UV Habitable Zone and the Possibility of the Persistent Life Existence: The Effects of Mass and Metallicity

NASA Astrophysics Data System (ADS)

Oishi, Midori; Kamaya, Hideyuki

2016-12-01

In addition to the habitable zone (HZ), the UV habitable zone (UV-HZ) is important when considering the existence of persistent life in the universe. The UV-HZ is defined as the area where the UV radiation field from a host star is moderate for persistent life existence. This is because UV is necessary for the synthesis of biochemical compounds. The UV-HZ must overlap the HZ when life appears and evolves. In this paper, following our previous study of the HZ, we examine the UV-HZ in cases with a stellar mass range from 0.08 to 4.00 M ⊙ with various metallicities during the main sequence phase. This mass range was chosen because we are interested in an environment similar to that of Earth. The effect of metallicity is reflected in the spectrum of the host stars, and we reexamine it in the context of the UV-HZ. The present work shows the effect of metallicity when that in the UV-HZ is less than that in the HZ. Furthermore, we find that the chance of persistent life existence declines as the metallicity decreases, as long as the UV radiation is not protected and/or boosted by any mechanisms. This is because the overlapped region of a persistent HZ and UV-HZ decreases. We find that the most appropriate stellar mass for the persistence of life existence is from 1.0 to 1.5 M ⊙ with metallicity Z = 0.02, and only about 1.2 M ⊙ with Z = 0.002. When Z = 0.0002, the chance of persistent life existence is very low, assuming that the ocean does not protect the life from UV radiation.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Danchi, William C.; Lopez, Bruno, E-mail: william.c.danchi@nasa.gov, E-mail: bruno.lopez@oca.eu

During the course of stellar evolution, the location and width of the habitable zone changes as the luminosity and radius of the star evolves. The duration of habitability for a planet located at a given distance from a star is greatly affected by the characteristics of the host star. A quantification of these effects can be used observationally in the search for life around nearby stars. The longer the duration of habitability, the more likely it is that life has evolved. The preparation of observational techniques aimed at detecting life would benefit from the scientific requirements deduced from the evolutionmore » of the habitable zone. We present a study of the evolution of the habitable zone around stars of 1.0, 1.5, and 2.0 M{sub Sun} for metallicities ranging from Z = 0.0001 to Z = 0.070. We also consider the evolution of the habitable zone from the pre-main sequence until the asymptotic giant branch is reached. We find that metallicity strongly affects the duration of the habitable zone for a planet as well as the distance from the host star where the duration is maximized. For a 1.0 M{sub Sun} star with near solar metallicity, Z = 0.017, the duration of the habitable zone is >10 Gyr at distances 1.2-2.0 AU from the star, whereas the duration is >20 Gyr for high-metallicity stars (Z = 0.070) at distances of 0.7-1.8 AU, and {approx}4 Gyr at distances of 1.8-3.3 AU for low-metallicity stars (Z = 0.0001). Corresponding results have been obtained for stars of 1.5 and 2.0 solar masses.« less

Influence of environment and mitochondrial heritage on the ecological characteristics of fish in a hybrid zone.

PubMed

Stolzenberg, Nicolas; Nguyen The, Bénédicte; Salducci, Marie Dominique; Cavalli, Laurent

2009-06-18

Ecological characteristics (growth, morphology, reproduction) arise from the interaction between environmental factors and genetics. Genetic analysis of individuals' life history traits might be used to improve our understanding of mechanisms that form and maintain a hybrid zone. A fish hybrid zone was used to characterize the process of natural selection. Data were collected during two reproductive periods (2001 and 2002) and 1117 individuals (nase, Chondrostama nasus nasus, sofie C. toxostoma toxostoma and hybrids) were sampled. Reproductive dates of the two parental species overlapped at sympatric sites. The nase had an earlier reproductive period than the sofie; males had longer reproductive periods for both species. Hybridisation between female nase and male sofie was the most likely. Hybrids had a reproductive period similar to the inherited parental mitochondrial type. Growth and reproductive information from different environments has been synthesised following a bayesian approach of the von Bertalanffy model. Hybrid life history traits appear to link with maternal heritage. Hybrid size from the age of two and size at first maturity appeared to be closer to the size of the maternal origin species (nase or sofie). Median growth rates for hybrids were similar and intermediate between those of the parental species. We observed variable life history traits for hybrids and pure forms in the different parts of the hybrid zone. Geometrical analysis of the hybrid fish shape gave evidence of two main morphologies with a link to maternal heritage. Selective mating seemed to be the underlying process which, with mitochondrial heritage, could explain the evolution of the studied hybrid zone. More generally, we showed the importance of studies on hybrid zones and specifically the study of individuals' ecological characteristics, to improve our understanding of speciation.

76 FR 63841 - Security Zone; Potomac River, Georgetown Channel, Washington, DC

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-14

... safeguard human life, vessels, and waterfront facilities while still sustaining the flow of commerce. The... restriction of vessel traffic is necessary to protect life, property and the environment, therefore, a 30-day... to safeguard life, property, and the environment on or near the navigable waters. Discussion of Rule...

76 FR 51255 - Security Zone; Potomac River, Georgetown Channel, Washington, DC

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-18

... security regimes designed to safeguard human life, vessels, and waterfront facilities while still... restriction of vessel traffic is necessary to protect life, property and the environment, therefore, a 30-day... maritime safety and security in order to safeguard life, property, and the environment on or near the...

77 FR 3118 - Security Zone; Choptank River and Cambridge Channel, Cambridge, MD

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-23

... security regimes designed to safeguard human life, vessels, and waterfront facilities while still... restriction of vessel traffic is necessary to protect life, property and the environment, therefore, a 30-day... maritime safety and security in order to safeguard life, property, and the environment on or near the...

77 FR 14703 - Safety Zone, Temporary Change for Recurring Fireworks Display Within the Fifth Coast Guard...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-13

.... Safety zone regulations are necessary to provide for the safety of life on navigable waters during the... To view comments, as well as documents mentioned in this preamble as being available in the docket... [[Page 14705

Assessment of Energy Savings Potential from the Use of Demand Control Ventilation Systems in General Office Spaces in California

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hong, Tianzhen; Fisk, William J.

2009-07-08

Demand controlled ventilation (DCV) was evaluated for general office spaces in California. A medium size office building meeting the prescriptive requirements of the 2008 California building energy efficiency standards (CEC 2008) was assumed in the building energy simulations performed with the EnergyPlus program to calculate the DCV energy savings potential in five typical California climates. Three design occupancy densities and two minimum ventilation rates were used as model inputs to cover a broader range of design variations. The assumed values of minimum ventilation rates in offices without DCV, based on two different measurement methods, were 81 and 28 cfm per occupant. These rates are based on the co-author's unpublished analyses of data from EPA's survey of 100 U.S. office buildings. These minimum ventilation rates exceed the 15 to 20 cfm per person required in most ventilation standards for offices. The cost effectiveness of applying DCV in general office spaces was estimated via a life cycle cost analyses that considered system costs and energy cost reductions. The results of the energy modeling indicate that the energy savings potential of DCV is largest in the desert area of California (climate zone 14), followed by Mountains (climate zone 16), Central Valley (climate zone 12), North Coast (climate zone 3), and South Coast (climate zone 6). The results of the life cycle cost analysis show DCV is cost effective for office spaces if the typical minimum ventilation rates without DCV is 81 cfm per person, except at the low design occupancy of 10 people per 1000 ft{sup 2} in climate zones 3 and 6. At the low design occupancy of 10 people per 1000 ft{sup 2}, the greatest DCV life cycle cost savings is a net present value (NPV) ofmore » $$0.52/ft{sup 2} in climate zone 14, followed by $$0.32/ft{sup 2} in climate zone 16 and $$0.19/ft{sup 2} in climate zone 12. At the medium design occupancy of 15 people per 1000 ft{sup 2}, the DCV savings are higher with a NPV $$0.93/ft{sup 2} in climate zone 14, followed by $$0.55/ft{sup 2} in climate zone 16, $$0.46/ft{sup 2} in climate zone 12, $$0.30/ft{sup 2} in climate zone 3, $$0.16/ft{sup 2} in climate zone 3. At the high design occupancy of 20 people per 1000 ft{sup 2}, the DCV savings are even higher with a NPV $$1.37/ft{sup 2} in climate zone 14, followed by $$0.86/ft{sup 2} in climate zone 16, $$0.84/ft{sup 2} in climate zone 3, $$0.82/ft{sup 2} in climate zone 12, and $0.65/ft{sup 2} in climate zone 6. DCV was not found to be cost effective if the typical minimum ventilation rate without DCV is 28 cfm per occupant, except at high design occupancy of 20 people per 1000 ft{sup 2} in climate zones 14 and 16. Until the large uncertainties about the base case ventilation rates in offices without DCV are reduced, the case for requiring DCV in general office spaces will be a weak case.« less

Subduction zone forearc serpentinites as incubators for deep microbial life

NASA Astrophysics Data System (ADS)

Plümper, Oliver; King, Helen E.; Geisler, Thorsten; Liu, Yang; Pabst, Sonja; Savov, Ivan P.; Rost, Detlef; Zack, Thomas

2017-04-01

Serpentinization-fueled systems in the cool, hydrated forearc mantle of subduction zones may provide an environment that supports deep chemolithoautotrophic life. Here, we examine serpentinite clasts expelled from mud volcanoes above the Izu-Bonin-Mariana subduction zone forearc (Pacific Ocean) that contain complex organic matter and nanosized Ni-Fe alloys. Using time-of-flight secondary ion mass spectrometry and Raman spectroscopy, we determined that the organic matter consists of a mixture of aliphatic and aromatic compounds and functional groups such as amides. Although an abiotic or subduction slab-derived fluid origin cannot be excluded, the similarities between the molecular signatures identified in the clasts and those of bacteria-derived biopolymers from other serpentinizing systems hint at the possibility of deep microbial life within the forearc. To test this hypothesis, we coupled the currently known temperature limit for life, 122 °C, with a heat conduction model that predicts a potential depth limit for life within the forearc at ˜10,000 m below the seafloor. This is deeper than the 122 °C isotherm in known oceanic serpentinizing regions and an order of magnitude deeper than the downhole temperature at the serpentinized Atlantis Massif oceanic core complex, Mid-Atlantic Ridge. We suggest that the organic-rich serpentinites may be indicators for microbial life deep within or below the mud volcano. Thus, the hydrated forearc mantle may represent one of Earth’s largest hidden microbial ecosystems. These types of protected ecosystems may have allowed the deep biosphere to thrive, despite violent phases during Earth’s history such as the late heavy bombardment and global mass extinctions.

Subduction zone forearc serpentinites as incubators for deep microbial life.

PubMed

Plümper, Oliver; King, Helen E; Geisler, Thorsten; Liu, Yang; Pabst, Sonja; Savov, Ivan P; Rost, Detlef; Zack, Thomas

2017-04-25

Serpentinization-fueled systems in the cool, hydrated forearc mantle of subduction zones may provide an environment that supports deep chemolithoautotrophic life. Here, we examine serpentinite clasts expelled from mud volcanoes above the Izu-Bonin-Mariana subduction zone forearc (Pacific Ocean) that contain complex organic matter and nanosized Ni-Fe alloys. Using time-of-flight secondary ion mass spectrometry and Raman spectroscopy, we determined that the organic matter consists of a mixture of aliphatic and aromatic compounds and functional groups such as amides. Although an abiotic or subduction slab-derived fluid origin cannot be excluded, the similarities between the molecular signatures identified in the clasts and those of bacteria-derived biopolymers from other serpentinizing systems hint at the possibility of deep microbial life within the forearc. To test this hypothesis, we coupled the currently known temperature limit for life, 122 °C, with a heat conduction model that predicts a potential depth limit for life within the forearc at ∼10,000 m below the seafloor. This is deeper than the 122 °C isotherm in known oceanic serpentinizing regions and an order of magnitude deeper than the downhole temperature at the serpentinized Atlantis Massif oceanic core complex, Mid-Atlantic Ridge. We suggest that the organic-rich serpentinites may be indicators for microbial life deep within or below the mud volcano. Thus, the hydrated forearc mantle may represent one of Earth's largest hidden microbial ecosystems. These types of protected ecosystems may have allowed the deep biosphere to thrive, despite violent phases during Earth's history such as the late heavy bombardment and global mass extinctions.

Subduction zone forearc serpentinites as incubators for deep microbial life

PubMed Central

Plümper, Oliver; Geisler, Thorsten; Liu, Yang; Pabst, Sonja; Savov, Ivan P.; Rost, Detlef; Zack, Thomas

2017-01-01

Serpentinization-fueled systems in the cool, hydrated forearc mantle of subduction zones may provide an environment that supports deep chemolithoautotrophic life. Here, we examine serpentinite clasts expelled from mud volcanoes above the Izu–Bonin–Mariana subduction zone forearc (Pacific Ocean) that contain complex organic matter and nanosized Ni–Fe alloys. Using time-of-flight secondary ion mass spectrometry and Raman spectroscopy, we determined that the organic matter consists of a mixture of aliphatic and aromatic compounds and functional groups such as amides. Although an abiotic or subduction slab-derived fluid origin cannot be excluded, the similarities between the molecular signatures identified in the clasts and those of bacteria-derived biopolymers from other serpentinizing systems hint at the possibility of deep microbial life within the forearc. To test this hypothesis, we coupled the currently known temperature limit for life, 122 °C, with a heat conduction model that predicts a potential depth limit for life within the forearc at ∼10,000 m below the seafloor. This is deeper than the 122 °C isotherm in known oceanic serpentinizing regions and an order of magnitude deeper than the downhole temperature at the serpentinized Atlantis Massif oceanic core complex, Mid-Atlantic Ridge. We suggest that the organic-rich serpentinites may be indicators for microbial life deep within or below the mud volcano. Thus, the hydrated forearc mantle may represent one of Earth’s largest hidden microbial ecosystems. These types of protected ecosystems may have allowed the deep biosphere to thrive, despite violent phases during Earth’s history such as the late heavy bombardment and global mass extinctions. PMID:28396389

Satisfaction with life and food-related life in Ecuadorian older adults.

PubMed

Schnettler, Berta; Lobos, Germán; Lapo, María Del Carmen; Adasme-Berríos, Cristian; Hueche, Clementina

2017-02-01

To distinguish typologies of seniors according to their levels of satisfaction with life and food-related life, and to characterize them according to the importance assigned to family, health-related aspects, eating habits, nutritional status and sociodemographic characteristics. A survey was administered to a non-probabilistic sample of 817 seniors aged 60 years and over, of both genders, resident in urban and rural zones of the province of Guayas, Ecuador. The instrument included: Satisfaction with Life Scale (SWLS), Satisfaction with Food-related Life (SWFL), the Health-related Quality of Life Index (HRQOL-4) and the Family Importance Scale (FIS). Eating habits, sociodemographic variables, approximate weight and height were asked about. A cluster analysis was used to distinguish three typologies that differed significantly in the scores on the SWLS, SWFL, FIS, number of days with mental health problems, self-perception of health status, body mass index, eating habits and zone of residence. Two typologies presented high levels of satisfaction with life and food-related life, although the variables associated with overall well-being and in the food domain were different in each typology. The results suggest that high levels of satisfaction with life and food-related life in Ecuadorian seniors are associated with both healthful eating habits and having lunch in company, fewer mental health problems and greater importance assigned to family.

Habitable zones around low mass stars and the search for extraterrestrial life.

PubMed

Kasting, J F

1997-06-01

Habitable planets are likely to exist around stars not too different from the Sun if current theories about terrestrial climate evolution are correct. Some of these planets may have evolved life, and some of the inhabited planets may have evolved O2-rich atmospheres. Such atmospheres could be detected spectroscopically on planets around nearby stars using a space-based interferometer to search for the 9.6 micron band of O3. Planets with O2-rich atmospheres that lie within the habitable zone around their parent star are, in all probability, inhabited.

Development of a model to compute the extension of life supporting zones for Earth-like exoplanets.

PubMed

Neubauer, David; Vrtala, Aron; Leitner, Johannes J; Firneis, Maria G; Hitzenberger, Regina

2011-12-01

A radiative convective model to calculate the width and the location of the life supporting zone (LSZ) for different, alternative solvents (i.e. other than water) is presented. This model can be applied to the atmospheres of the terrestrial planets in the solar system as well as (hypothetical, Earth-like) terrestrial exoplanets. Cloud droplet formation and growth are investigated using a cloud parcel model. Clouds can be incorporated into the radiative transfer calculations. Test runs for Earth, Mars and Titan show a good agreement of model results with observations.

75 FR 41106 - Amendments to the Water Quality Regulations, Water Code and Comprehensive Plan to Update Water...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-15

... (also called water quality criteria) for human health and aquatic life for toxic pollutants in the... Commission in 1996 adopted water quality criteria for human health and aquatic life for Water Quality Zones 2... Objectives for Toxic Pollutants for the Protection of Aquatic Life'', Table 6, ``Stream Quality Objectives...

Service life assessment of timber highway bridges in USA climate zones

Treesearch

James P. Wacker; Brian K. Brashaw; Thomas G. Williamson; P. David Jones; Matthew S. Smith; Travis K. Hosteng; David L. Strahl; Lola E. Coombe; V.J. Gopu

2014-01-01

As engineers begin to estimate life-cycle costs and sustainable design approaches for timber bridges, there is a need for more reliable data about their durability and expected service life. This paper summarizes a comprehensive effort to assess the current condition of more than one hundred timber highway bridge superstructures throughout the United States. This...

The Zone of Proximal "Teacher" Development

ERIC Educational Resources Information Center

Warford, Mark K.

2011-01-01

Toward the end of his short life, Lev Vygotsky found himself teaching teachers in a remote part of the USSR. Though his influence as a developmental psychologist is well-established, little is known about his approach to teacher development. This article applies the researcher's core concept, the zone of proximal development to teacher education.…

78 FR 29091 - Safety Zone; Outer Banks Bluegrass Festival; Shallowbag Bay, Manteo, NC

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-17

...-AA00 Safety Zone; Outer Banks Bluegrass Festival; Shallowbag Bay, Manteo, NC AGENCY: Coast Guard, DHS... the Outer Banks Bluegrass Festival. This action is necessary to protect the life and property of the... vessels from a portion of Shallowbag Bay River during the Outer Banks Bluegrass Festival Fireworks display...

78 FR 40394 - Safety Zone; Outer Banks Bluegrass Festival; Shallowbag Bay, Manteo, NC

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-05

...-AA00 Safety Zone; Outer Banks Bluegrass Festival; Shallowbag Bay, Manteo, NC AGENCY: Coast Guard, DHS... Festival. This action is necessary to protect the life and property of the maritime public from the hazards... Shallowbag Bay River during the Outer Banks Bluegrass Festival Fireworks display. DATES: This rule is...

78 FR 57570 - Safety Zone; Motion Picture Production; Chicago, Illinois

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-19

...-AA00 Safety Zone; Motion Picture Production; Chicago, Illinois AGENCY: Coast Guard, DHS. ACTION: Notice... motion picture filming in Calumet Harbor, Chicago, IL from 9 p.m. until 6 a.m., from September 15 through September 29, 2013. This action is necessary and intended to ensure safety of life on navigable waters...

75 FR 18056 - Safety Zone; Fireworks Display, Patuxent River, Solomons Island Harbor, MD

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-09

..., DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a temporary safety zone... necessary to provide for the safety of life on navigable waters during a fireworks display launched from... protect the maritime public in a portion of Solomons Island Harbor. DATES: This rule is effective from 7...

78 FR 39599 - Safety Zone; Fort Monroe Fireworks Display, Chesapeake Bay, Hampton, VA

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-02

.... ACTION: Temporary Final rule. SUMMARY: The Coast Guard is establishing a temporary safety zone on the... intended to restrict vessel traffic movement in the specified area in order to protect the life and... Federal holidays. FOR FURTHER INFORMATION CONTACT: If you have questions on this temporary rule, call or...

Critical Zone Services as a Measure for Evaluating the Trade-offs in Intensively Managed Landscapes

NASA Astrophysics Data System (ADS)

Richardson, M.; Kumar, P.

2015-12-01

The Critical Zone includes the range of biophysical processes occurring from the top of the vegetation canopy to the weathering zone below the groundwater table. These services (Field et al. 2015) provide a measure to value processes that support the goods and services from our landscapes. In intensively managed landscapes the provisioning and regulating services are being altered through anthropogenic energy inputs so as to derive more agricultural productivity from the landscapes. Land use change and other alterations to the environment result in positive and/or negative net Critical Zone services. Through studies in the Critical Zone Observatory for Intensively Managed Landscapes (IMLCZO), this research seeks to answer questions such as: Are perennial bioenergy crops or annual replaced crops better for the land and surrounding environment? How do we evaluate the products and services from the land for the energy and resources we put in? Before the economic valuation of Critical Zone services, these questions seemed abstract. However, with developments such as Critical Zone services and life cycle assessments, they are more concrete. To evaluate the trade-offs between positive and negative impacts, life cycle assessments are used to create an inventory of all the energy inputs and outputs in a landscape management system. Total energy is computed by summing the mechanical energy used to construct tile drains, fertilizer, and other processes involved in intensely managed landscapes and the chemical energy gained by the production of biofuels from bioenergy crops. A multi-layer canopy model (MLCan) computes soil, water, and nutrient outputs for each crop type, which can be translated into Critical Zone services. These values are then viewed alongside the energy inputs into the system to show the relationship between agricultural practices and their corresponding ecosystem and environmental impacts.

Delivery of Volatiles to Habitable Planets in Extrasolar Planetary Systems

NASA Technical Reports Server (NTRS)

Chambers, John E.; Kress, Monika E.; Bell, K. Robbins; Cash, Michele; DeVincenzi, Donald L. (Technical Monitor)

2000-01-01

The Earth can support life because: (1) its orbit lies in the Sun's habitable zone', and (2) it contains enough volatile material (e.g. water and organics) for life to flourish. However, it seems likely that the Earth was drier when it formed because it accreted in a part of the Sun's protoplanetary nebula that was too hot for volatiles to condense. If this is correct, water and organics must have been delivered to the habitable zone, after dissipation of the solar nebula, from a 'wet zone' in the asteroid belt or the outer solar system, where the nebula was cool enough for volatiles to condense. Material from the wet zone would have been delivered to the Earth by Jupiter and Saturn. Gravitational perturbations from these giant planets made much of the wet zone unstable, scattering volatile-rich planetesimals and protoplanets across the Solar System. Some of these objects ultimately collided with the inner Planets which themselves lie in a stable part of the Solar System. Giant planets are now being discovered orbiting other sunlike stars. To date, these planets have orbits and masses very different from Jupiter and Saturn, such that few if any of these systems is likely to have terrestrial planets in the star's habitable zone. However, new discoveries are anticipated due to improved detector sensitivity and the increase in the timespan of observations. Here we present numerical experiments examining the range of giant-planet characteristics that: (1) allow stable terrestrial Planets to exist in a star's habitable zone, and (2) make a large part of the star's wet zone weakly unstable, thus delivering volatiles to the terrestrial planets over an extended period of time after the dissipation of the solar nebula.

A SIMPLE EVOLUTIONAL MODEL OF THE UV HABITABLE ZONE AND THE POSSIBILITY OF PERSISTENT LIFE EXISTENCE: THE EFFECTS OF MASS AND METALLICITY

DOE Office of Scientific and Technical Information (OSTI.GOV)

Oishi, Midori; Kamaya, Hideyuki

In addition to the habitable zone (HZ), the UV habitable zone (UV-HZ) is important when considering the existence of persistent life in the universe. The UV-HZ is defined as the area where the UV radiation field from a host star is moderate for persistent life existence. This is because UV is necessary for the synthesis of biochemical compounds. The UV-HZ must overlap the HZ when life appears and evolves. In this paper, following our previous study of the HZ, we examine the UV-HZ in cases with a stellar mass range from 0.08 to 4.00 M {sub ☉} with various metallicities during the main sequencemore » phase. This mass range was chosen because we are interested in an environment similar to that of Earth. The effect of metallicity is reflected in the spectrum of the host stars, and we reexamine it in the context of the UV-HZ. The present work shows the effect of metallicity when that in the UV-HZ is less than that in the HZ. Furthermore, we find that the chance of persistent life existence declines as the metallicity decreases, as long as the UV radiation is not protected and/or boosted by any mechanisms. This is because the overlapped region of a persistent HZ and UV-HZ decreases. We find that the most appropriate stellar mass for the persistence of life existence is from 1.0 to 1.5 M {sub ☉} with metallicity Z  = 0.02, and only about 1.2 M {sub ☉} with Z  = 0.002. When Z  = 0.0002, the chance of persistent life existence is very low, assuming that the ocean does not protect the life from UV radiation.« less

Carbon Fiber Reinforced Polymer Grids for Shear and End Zone Reinforcement in Bridge Beams

DOT National Transportation Integrated Search

2018-01-01

Corrosion of reinforcing steel reduces life spans of bridges throughout the United States; therefore, using non-corroding carbon fiber reinforced polymer (CFRP) reinforcement is seen as a way to increase service life. The use of CFRP as the flexural ...

The Case for Group Counseling as the Means for Eliminating Erroneous Zones.

ERIC Educational Resources Information Center

Dyer, Wayne W.

1979-01-01

Presents a case for group counseling, a curricular intervention that aids young people in learning how to make decisions, take charge of their emotions and reorder their thinking, and focus on themselves as human beings. They learn to shed their erroneous zones and to opt for a neurosis-free, self-actualized life. (Author/BEF)

77 FR 27621 - Special Local Regulations and Safety Zone; War of 1812 Bicentennial Commemorations, Chesapeake...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-11

...] RIN 1625-AA08, 1625-AA00 Special Local Regulations and Safety Zone; War of 1812 Bicentennial... Chesapeake Bay and Port of Baltimore, Maryland for War of 1812 Bicentennial Commemorations activities. These actions are necessary to provide for the safety of life on navigable waters before, during, and after War...

77 FR 15323 - Special Local Regulations and Safety Zone; War of 1812 Bicentennial Commemorations, Chesapeake...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-15

...] RIN 1625-AA08, AA00 Special Local Regulations and Safety Zone; War of 1812 Bicentennial Commemorations... Chesapeake Bay and Port of Baltimore, Maryland for War of 1812 Bicentennial Commemorations activities. This action is necessary to provide for the safety of life on navigable waters before, during, and after War...

40 CFR Appendix E to Part 300 - Oil Spill Response

Code of Federal Regulations, 2010 CFR

2010-07-01

..., other waters of the high seas subject to the NCP, and the land surface or land substrata, ground waters... response equipment; and a district response advisory team. Contiguous zone means the zone of the high seas... of the discharge. 2.2Priorities. (a) Safety of human life must be given the highest priority during...

78 FR 31840 - Safety Zone; USO Patriotic Festival Air Show, Atlantic Ocean; Virginia Beach, VA

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-28

...-AA00 Safety Zone; USO Patriotic Festival Air Show, Atlantic Ocean; Virginia Beach, VA AGENCY: Coast... provide for the safety of life on navigable waters during the USO Patriotic Festival Air Show. This action... Patriotic Festival Air Show, Atlantic Ocean; Virginia Beach, VA. (a) Regulated Area. The following area is a...

78 FR 56151 - Safety Zone, North Atlantic Ocean; Virginia Beach, VA

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-12

... final rule. SUMMARY: The Coast Guard is establishing a safety zone on the navigable waters of the North... life and property of the maritime public and spectators from the hazards associated with fireworks displays. DATES: This rule will be effective from 9:20 p.m. to 10:10 p.m. on September 12, 2013. ADDRESSES...

78 FR 36424 - Special Local Regulations for Summer Events; Captain of the Port Lake Michigan Zone

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-18

... Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing temporary special local regulations for three summer events within the Captain of the Port Lake Michigan Zone. This rule is intended to provide for the safety of life and property on navigable waters immediately prior to...

76 FR 30020 - Safety Zone; Wicomico Community Fireworks, Great Wicomico River, Mila, VA

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-24

.... ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a temporary safety zone on the.... This action is necessary to provide for the safety of life on navigable waters during the Wicomico... rule is effective from 9 p.m. on July 2, 2011, until 10 p.m. on July 3, 2011. ADDRESSES: Documents...

75 FR 42608 - Safety Zone; Lyme Community Days, Chaumont Bay, NY

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-22

... final rule. SUMMARY: The Coast Guard is establishing a temporary safety zone for Lyme Community Days... intended to ensure safety of life on navigable waters immediately prior to, during, and immediately after the fireworks event. DATES: This rule is effective from 9:30 p.m. to 10 p.m. on July 24, 2010...

Yeast activities involved in carbon and nitrogen cycles in Antarctica

USDA-ARS?s Scientific Manuscript database

Antarctica and sub Antarctic regions are characterized by extreme conditions for life such as low temperatures and nutrient availability, high solar radiation and dryness, however, microorganisms from the three domains of life have been found as common inhabitants of soils and waters from those zone...

Life prediction for high temperature low cycle fatigue of two kinds of titanium alloys based on exponential function

NASA Astrophysics Data System (ADS)

Mu, G. Y.; Mi, X. Z.; Wang, F.

2018-01-01

The high temperature low cycle fatigue tests of TC4 titanium alloy and TC11 titanium alloy are carried out under strain controlled. The relationships between cyclic stress-life and strain-life are analyzed. The high temperature low cycle fatigue life prediction model of two kinds of titanium alloys is established by using Manson-Coffin method. The relationship between failure inverse number and plastic strain range presents nonlinear in the double logarithmic coordinates. Manson-Coffin method assumes that they have linear relation. Therefore, there is bound to be a certain prediction error by using the Manson-Coffin method. In order to solve this problem, a new method based on exponential function is proposed. The results show that the fatigue life of the two kinds of titanium alloys can be predicted accurately and effectively by using these two methods. Prediction accuracy is within ±1.83 times scatter zone. The life prediction capability of new methods based on exponential function proves more effective and accurate than Manson-Coffin method for two kinds of titanium alloys. The new method based on exponential function can give better fatigue life prediction results with the smaller standard deviation and scatter zone than Manson-Coffin method. The life prediction results of two methods for TC4 titanium alloy prove better than TC11 titanium alloy.

High visibility safety apparel and nighttime conspicuity of pedestrians in work zones.

PubMed

Sayer, James R; Mefford, Mary Lynn

2004-01-01

Every year numerous occupational fatalities result from pedestrians being struck by motor vehicles intruding into work zones. Attributes of retroreflective personal safety garments on pedestrian conspicuity at night were assessed in a field study. Using instrumented vehicles on a closed track, participants drove through simulated work zones attempting to detect pedestrians located in the work zones. Configuration of the retroreflective trim, trim color, placement in the work zone, and driver age significantly affected pedestrian conspicuity. Intensity and the amount of retroreflective trim did not. Personal safety garments incorporating retroreflective trim significantly improve pedestrian conspicuity in work zones. The results emphasize the importance of retroreflective trim on personal safety garments, particularly if the trim is located on garment sleeves. We examine the design attributes that contribute to making a personal safety garment conspicuous. The results have implications regarding preferred garment designs, industry standards, and service life of personal safety garments.

77 FR 56115 - Safety Zone for Fireworks Display, Potomac River, National Harbor Access Channel; Oxon Hill, MD

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-12

..., MD AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a... safety of life on navigable waters during a fireworks display launched from a floating platform located... zone is intended to protect the maritime public in a portion of the Potomac River. DATES: This rule is...

76 FR 70647 - Safety Zone; Fireworks Display, Potomac River, National Harbor Access Channel, MD

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-15

... Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a safety zone upon specified waters of the Potomac River. This action is necessary to provide for the safety of life on... maritime public in a portion of the Potomac River. DATES: This rule is effective from 6 p.m. on November 19...

77 FR 22523 - Safety Zone; 2012 Ocean City Air Show; Atlantic Ocean, Ocean City, MD

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-16

...-AA00 Safety Zone; 2012 Ocean City Air Show; Atlantic Ocean, Ocean City, MD AGENCY: Coast Guard, DHS... the navigable waters of the Atlantic Ocean in Ocean City, MD. This action is necessary to provide for the safety of life on navigable waters during the 2012 Ocean City Air Show. This action is intended to...

76 FR 31235 - Safety Zone; Ocean City Air Show, Atlantic Ocean, Ocean City, MD

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-31

...-AA00 Safety Zone; Ocean City Air Show, Atlantic Ocean, Ocean City, MD AGENCY: Coast Guard, DHS. ACTION... in the vicinity of Ocean City, MD to support the Ocean City Air Show. This action is necessary to provide for the safety of life on navigable waters during the Ocean City Air Show. This action is intended...

78 FR 1753 - Security Zone, Potomac and Anacostia Rivers; Washington, DC

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-09

... immediate action, the restriction of vessel traffic is necessary to protect life, property and the... of the Port the ability to implement comprehensive port security regimes designed to safeguard human life, vessels, and waterfront facilities while still sustaining the flow of commerce. The Captain of...

75 FR 12688 - Safety Zone; Gallants Channel, Beaufort, NC

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-17

... immediate action is needed to ensure the safety of human life and property from the hazards of falling... life and property on navigable waters and due to the hazards associated with potential falling debris... which do not individually or cumulatively have a significant effect on the human environment. This rule...

78 FR 54392 - Security Zone, Baltimore Harbor, Baltimore's Inner Harbor; Baltimore, MD

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-04

... restriction of vessel traffic is necessary to protect life, property and the environment, therefore, a 30-day... of the Port the ability to implement comprehensive port security regimes designed to safeguard human life, vessels, and waterfront facilities while still sustaining the flow of commerce. The Captain of...

Astrobiological Effects of Stellar Radiation in Circumstellar Environments

NASA Astrophysics Data System (ADS)

Cuntz, Manfred; Gurdemir, Levent; Guinan, Edward F.; Kurucz, Robert L.

2006-10-01

The centerpiece of all life on Earth is carbon-based biochemistry. Previous scientific research has suggested that biochemistry based on carbon may also play a decisive role in extraterrestrial life forms, i.e., alien life outside of Earth, if existent. In the following, we explore if carbon-based macromolecules (such as DNA) in the environments of stars other than the Sun are able to survive the effects of energetic stellar radiation, such as UV-C in the wavelength band between 200 and 290 nm. We focus on main-sequence stars akin to the Sun, but of hotter (F-type stars) and cooler (K- and M-type stars) surface temperature. Emphasis is placed on investigating the radiative environment in stellar habitable zones (HZs). Stellar habitable zones have an important relevance in astrobiology because they constitute circumstellar regions in which a planet of suitable size can have surface temperatures for water to exist in liquid form.

Mid-continent earthquake zones; lessons from New Madrid, Missouri

USGS Publications Warehouse

Mitchell, B. J.

1991-01-01

Many seismically active regions occur throughout the world as concentrated zones surrounded by the relatively stable crust of shields or platforms. Examples occur in central and eastern North America, northeastern Brazil, Australia, Norway, Svalbard, Greenland, and other places. Some of these zones, such as those at New Madrid, Missouri, and in the St. Lawrence Valley on the Canadian border, extend over relatively large areas and are marked by a high level of seismicity. Others, such as that near Anna Ohio, are smaller, and the level of activity is lower. Some zones are occasinoally sites for major earthquakes which, if they are in populated regions, can cause widespread destrucion and loss of life. 

Species Diversity Distribution Patterns of Chinese Endemic Seed Plants Based on Geographical Regions.

PubMed

Huang, Jihong; Ma, Keping; Huang, Jianhua

2017-01-01

Based on a great number of literatures, we established the database about the Chinese endemic seed plants and analyzed the compositions, growth form, distribution and angiosperm original families of them within three big natural areas and seven natural regions. The results indicate that the above characters of Chinese endemic plants take on relative rule at the different geographical scales. Among the three big natural areas, Eastern Monsoon area has the highest endemic plants richness, whereas Northwest Dryness area is the lowest. For life forms, herbs dominate. In contrast, the proportion of herbs of Eastern Monsoon area is remarkable under other two areas. Correspondingly the proportions of trees and shrubs are substantially higher than other two. For angiosperm original families, the number is the highest in Eastern Monsoon area, and lowest in Northwest Dryness area. On the other hand, among the seven natural regions, the humid and subtropical zone in Central and Southern China has the highest endemic plants richness, whereas the humid, hemi-humid region and temperate zone in Northeast China has the lowest. For life forms, the proportion of herbs tends to decrease from humid, hemi-humid region and temperate zone in Northeast China to humid and tropical zone in Southern China. Comparably, trees, shrubs and vines or lianas increase with the same directions. This fully represents these characters of Chinese endemic plants vary with latitudinal gradients. Furthermore, as to the number of endemic plants belonging to angiosperm original families, the number is the most in humid and subtropical zone in Center and Southern China, and tropical zone in Southern China in the next place. In contrast, the endemic plant of these two regions relatively is richer than that of The Qinghai-Tibet alpine and cold region. All above results sufficiently reflect that the Chinese endemic plants mainly distribute in Eastern Monsoon area, especially humid and subtropical zone in Center and Southern China and tropical zone in Southern China. Furthermore, the flora of Eastern Monsoon area, in particular humid and subtropical zone in Center and Southern China and tropical zone in Southern China, is more ancient and original than that of Northwest Dryness area and Qinghai-Tibet alpine and cold area.

Transport of environmental tracers through a karst system with a thick unsaturated zone

NASA Astrophysics Data System (ADS)

Geyer, Tobias; Sültenfuss, Jürgen; Eichinger, Florian; Sauter, Martin

2010-05-01

The transport of the environmental tracers tritium (3H), krypton-85 (85Kr) and helium (3He) in a karst system is investigated. Differences between mean tracer ages determined in spring water are explained by slow percolation of water through the thick unsaturated zone reflecting the importance of slow and diffuse unsaturated flow processes in these systems. Mean tracer ages on the Gallusquelle spring (Swabian Alb) were determined with lumped parameter modeling and decrease in the following order: 3H >> 85Kr > 3He. Since 3H is part of the water molecule it enters a karst system via precipitation, i.e. the mean 3H age is a measure of water flow through the whole karst system, including the unsaturated and saturated zone. The mean 85Kr age and 3H/3He age are measures of time since groundwater recharge arrived at the water table. Therefore our results indicate a long travel time of 3H through the unsaturated zone of the karst system. The interpretation is supported by a two-dimensional numerical simulation of flow and transport in a fissured matrix block that contains a thick unsaturated zone (ca. 100 m) and is drained by a conduit. Transport simulation is performed in the sense of backtracking, i.e. the flow field is reversed, and the boundary conditions are adapted accordingly. At any position in the model domain, the time required for a water molecule to reach the outlet is estimated corresponding to the "life expectancy" (Cornaton and Perrochet 2006), i.e. the life expectancy on the outlet is zero. The simulation of life expectancy of water in the matrix block shows (1) the importance of heterogeneities for interpretation of groundwater ages, (2) the location of stagnant zones in areas of low hydraulic permeability and/or low hydraulic gradient and (3) that flow through unsaturated fissured matrix blocks may cause a considerable travel time of water through a karst system. The travel time of water from the recharge area to the discharge point for the shown example is about 15 years with a travel time of water through the unsaturated zone of 10 years (Geyer 2008). This result reflects the variation of estimated ages for different tracers sampled at the Gallusquelle spring. Additionally, we demonstrate that depending on boundary conditions, the unsaturated zone of a karst system may provide a large water storage since the porous matrix can be expected to be close to saturation and the volume fraction of fissures and conduits is small. Literature Cornaton, F., Perrochet, P. (2006): Ground-water age, life expectancy and transit time distributions in advective-dispersive systems: 1. Generalized reservoir theory. - Advances in Water Resources 29 (9): 1267-1291. Geyer, T. (2008): Characterisation of flow and transport in karst aquifers at catchment scale, Ph.D. diss., Georg-August-Universität Göttingen, 103 pp.

Carbon Dioxide Effects Research and Assessment Program. The role of tropical forests on the world carbon cycle

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brown, S.; Lugo, A. E.; Liegel, B.

1980-08-01

Tropical forests constitute about half of the world's forest and are characterized by rapid rates of organic matter turnover and high storages of organic matter. Tropical forests are considered to be one of the most significant terrestrial elements in the equation that balances the carbon cycle of the world. As discussed in the paper by Tosi, tropical and subtropical latitudes are more complex in terms of climate and vegetation composition than temperate and boreal latitudes. The implications of the complexity of the tropics and the disregard of this complexity by many scientists is made evident in the paper by Brownmore » and Lugo which shows that biomass estimates for tropical ecosystems have been overestimated by at least 100%. The paper by Brown shows that that rates of succession in the tropics are extremely rapid in terms of the ability of moist and wet forests to accumulate organic matter. Yet, in arid tropical Life Zones succession is slow. This leads to the idea that the question of whether tropical forests are sinks or sources of carbon must be analyzed in relation to Life Zones and to intensities of human activity in these Zones. The paper by Lugo presents conceptual models to illustrate this point and the paper by Tosi shows how land uses in the tropics also correspond to Life Zone characteristics. The ultimate significance of land use to the question of the carbon balance in a large region is addressed in the paper by Detwiler and Hall.« less

Optimal seasonal schedules and the relative dominance of heteromorphic and isomorphic life cycles in macroalgae.

PubMed

Bessho, Kazuhiro; Iwasa, Yoh

2010-11-21

Marine macroalgae (seaweed) show diverse life cycles. Species with a heteromorphic life cycle have a large multicellular algal body in one generation but have a very small body in the second generation of the same year. In contrast, the diploid and haploid life forms of isomorphic species have similar morphology, and these species often have more than two generations in a year. Here, we first study the optimal life cycle schedule of marine macroalgae when daily mortality changes seasonally, and then we discuss the conditions for coexistence and relative dominance of different life cycles. According to the optimal life cycle schedule, heteromorphic species tend to have a generation with a large algal body when mortality is low, and a microscopic-sized generation when mortality is high. In contrast, isomorphic species tend to mature when body size reaches a threshold value that is the same for different generations. We then examine the coexistence of the two life cycles when growth rate decreases with biomass. The model predicts that (1) at high latitudes (i.e., in strongly seasonal environments), heteromorphic species are likely to dominate over isomorphic species, and (2) species with a heteromorphic life cycle should dominate in the supratidal and upper intertidal zones where macroalgae tend to suffer high mortality, and also in the subtidal zone, where mortality is low, whereas isomorphic species are likely to be more successful when mortality is intermediate. These predictions are consistent with the observed distribution patterns of the two life cycles in macroalgae. Copyright © 2010 Elsevier Ltd. All rights reserved.

Social safety and medical maintenance of the labour pool in surveillance areas of the nuclear power plants.

PubMed

Prylipko, V A; Ozerova, Yu Yu; Kotsubinskij, O V; Morozova, M M; Petrychenko, O O; Bondarenko, I V

2017-12-01

To study the contentment of population of NPP surveillance areas i.e. monitoring zones with specific components of quality of life, namely the social security, medical care, and socio economic compensation of risk. A sociological study of public opinion about the specific components of quality of life has been conducted in population of the NPP monitoring zone. A questionnaire with independent question blocks was developed. A non repeatable probabilistic selection was applied in population opinion poll. The sampled population was calculated on the basis of the total population living in the NPP monitoring zone. Sample error not exceeded 7.0%. A comparative assessment of the responses of various groups of the able bodied population on issues of social security, medical care, socio economic compensation of risk and analysis of statistical data for 2011-2015 on the resource potential of medical facility of the nuclear power plant overspill town has been conducted. The safety and security status is rated at below the average. Documents regulating the life safety of pop ulation of NPP monitoring zone provide them no confidence in their security. Probability estimates of man made accidents are higher in urban population and depend on education level. The socialized health care is assessed on low and average levels according to the studied parameters. Among the types of medical care the providing of nec essary medical goods, preventive examinations, scheduled medical examination service, ambulance activity, and medical psychological aid need to be improved. There was no significant change in resource potential of special ized healthcare infirmary of NPP overspill town for the last 5 years. Low rating by the monitoring zone population of work efficiency of health facilities is determined by a set of factors, some of which lies in the plane of state socio economic problems. Choice priority of the direct sub ventions in population of monitoring zone depends on the place of residence and occupation. Provisions on social security, protection and medical care of population of the NPP monitoring zones in Ukraine do not correspond to European standards and require a revision. V.A. Prylipko, Yu.Yu. Ozerova, O.V. Kotsubinskij, M.M. Morozova, O.O. Petrychenko, I.V. Bondarenko.

How big is the Ocean Dead Zone off the Coast of California?

NASA Astrophysics Data System (ADS)

Hofmann, A. F.; Peltzer, E. T.; Walz, P. M.; Brewer, P. G.

2010-12-01

The term “Ocean Dead Zone”, generally referring to a zone that is devoid of aerobic marine life of value to humans, is now widely used in the press and scientific literature but it appears to be not universally defined. The global assessment and monitoring of ocean dead zones, however, is of high public concern due to the considerable economic value associated with impacted fisheries and with questions over the growth of these zones forced by climate change. We report on the existence of a zone at ~850m depth off Santa Monica, California where dissolved oxygen (DO) levels are 1 μmol/kg; an order of magnitude below any existing definition of an “Ocean Dead Zone”. ROV dives show the region to be visually devoid of all aerobic marine life. But how large is this dead zone, and how may its boundaries be defined? Without an accepted definition we cannot report this nor can we compare it to other dead zones reported elsewhere in the world. “Dead zones” are now assessed solely by DO levels. A multitude of values in different units are used (Fig 1), which are clearly not universally applicable. This seriously hampers an integrated global monitoring and management effort and frustrates the development of valid connections with climate change and assessment of the consequences. Furthermore, input of anthropogenic CO2 can also stress marine life. Recent work supported by classical data suggests that higher pCO2 influences the thermodynamic energy efficiency of oxic respiration (CH2O + O2 -> CO2 + H2O). The ratio pO2/pCO2, called the respiration index (RI), emerges as the critical variable, combining the impacts of warming on DO and rising CO2 levels within a single, well defined quantity. We advocate that future monitoring efforts report pO2 and pCO2 concurrently, thus making it possible to classify, monitor and manage “dead zones” within a standard reference system that may include, as with e.g, hurricanes, differing categories of intensity. Fig.1. A DO profile off Southern California with overlay of commonly used DO thresholds (μmolO2/kg); “dead zones” may occur anywhere from 250 - 2,200 m depth. The widely reported “dead zone” off the Mississippi delta is defined by DO of < 2 mg/l (~ 64 μmol/kg).

Gone before You Know It: Urban School Reform and the Short Life of the Education Action Zone Initiative

ERIC Educational Resources Information Center

Franklin, Barry M.

2005-01-01

This essay explores the fluctuations in and short-lived nature of urban school reform through a study of the Education Action Zone (EAZ) programme of Britain's New Labour government. Using the notion of civic capacity as a theoretical framework, the essay looks at this reform from the perspectives of its government proponents, critics outside of…

76 FR 48718 - Safety Zones; August Fireworks Displays and Swim Events in the Captain of the Port New York Zone

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-09

... AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing four... fireworks displays and swim events. This action is necessary to provide for the safety of life on navigable... prohibited unless authorized by the COTP New York. DATES: This rule is effective in the CFR on August 9, 2011...

The Inhabitance Paradox: how habitability and inhabitancy are inseparable

NASA Astrophysics Data System (ADS)

Goldblatt, C.

2015-12-01

The dominant paradigm in assigning "habitability" to terrestrial planets is to define a circumstellar habitable zone: the locus of orbital radii in which the planet is neither too hot nor too cold for life as we know it. One dimensional climate models have put theoretically impressive boundaries on this: a runaway greenhouse or water loss at the inner edge (Venus), and low-latitude glaciation followed by formation of CO2 clouds at the outer edge. A cottage industry now exists to "refine" the definition of these boundaries each year to the third decimal place of an AU. Using exactly that kind of model, I'll show that the different climate states can overlap very substantially and that "snowball Earth", temperate climate and a post-runaway climate can all be stable under the same solar flux. Furthermore, the radial extent of the temperature climate band is very narrow for pure water atmospheres. The width of the habitable zone is determined by the atmospheric inventories of di-nitrogen and carbon dioxide. Yet Earth teaches us that these abundances are very heavily influenced (perhaps even controlled) by biology. This is paradoxical: the habitable zone seeks to define the region a planet should be capable of harbouring life; yet whether the planet is inhabited will determine whether the climate may be habitable at any given distance from the star. This matters, because future life detection missions may use habitable zone boundaries in mission design. A historical view of solar system exploration helps frame the problem; robotic exploration of the outer solar system revealed the un-imagined nature of the Jovian and Saturnian moons, whilst showing that the Venusian jungle died long ago. Prediction will fall to data but the unexpected may emerge. To soften that fall we should revise the paradigm of habitability to acknowledge that habitability depends on inhabitance; for life as we know it is a planetary scale--and planet dominating--phenomenon.

Imaging of earthquake faults using small UAVs as a pathfinder for air and space observations

USGS Publications Warehouse

Donnellan, Andrea; Green, Joseph; Ansar, Adnan; Aletky, Joseph; Glasscoe, Margaret; Ben-Zion, Yehuda; Arrowsmith, J. Ramón; DeLong, Stephen B.

2017-01-01

Large earthquakes cause billions of dollars in damage and extensive loss of life and property. Geodetic and topographic imaging provide measurements of transient and long-term crustal deformation needed to monitor fault zones and understand earthquakes. Earthquake-induced strain and rupture characteristics are expressed in topographic features imprinted on the landscapes of fault zones. Small UAVs provide an efficient and flexible means to collect multi-angle imagery to reconstruct fine scale fault zone topography and provide surrogate data to determine requirements for and to simulate future platforms for air- and space-based multi-angle imaging.

Crossing disciplines and scales to understand the critical zone

USGS Publications Warehouse

Brantley, S.L.; Goldhaber, M.B.; Vala, Ragnarsdottir K.

2007-01-01

The Critical Zone (CZ) is the system of coupled chemical, biological, physical, and geological processes operating together to support life at the Earth's surface. While our understanding of this zone has increased over the last hundred years, further advance requires scientists to cross disciplines and scales to integrate understanding of processes in the CZ, ranging in scale from the mineral-water interface to the globe. Despite the extreme heterogeneities manifest in the CZ, patterns are observed at all scales. Explanations require the use of new computational and analytical tools, inventive interdisciplinary approaches, and growing networks of sites and people.

Rivers of the Andes and the Amazon Basin: Deciphering global change from the hydroclimatic variability in the critical zone

NASA Astrophysics Data System (ADS)

Moreira-Turcq, Patricia; Carlo Espinoza, Jhan; Filizola, Naziano; Martinez, Jean-Michel

2018-01-01

The Critical Zone has been defined as the thin layer of the continental surfaces extending from fresh bedrock and the bottom of groundwater up to vegetation canopy, where soil, rock, water, air, and living organisms interact (Banwart et al., 2012; Lin et al., 2011). Despite the Critical Zone's importance to terrestrial life, it remains poorly understood. In this context, understanding the complex interactions between physical, chemical, and biological processes of the Critical Zone requires long-term observations (Anderson et al., 2012; Brantley et al., 2017), not only because different mechanisms have varying time frames, but also because it is necessary to monitor its natural and anthropogenic evolution in response to global climate and environmental changes.

ABIOTIC OXYGEN-DOMINATED ATMOSPHERES ON TERRESTRIAL HABITABLE ZONE PLANETS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wordsworth, Robin; Pierrehumbert, Raymond

2014-04-20

Detection of life on other planets requires identification of biosignatures, i.e., observable planetary properties that robustly indicate the presence of a biosphere. One of the most widely accepted biosignatures for an Earth-like planet is an atmosphere where oxygen is a major constituent. Here we show that lifeless habitable zone terrestrial planets around any star type may develop oxygen-dominated atmospheres as a result of water photolysis, because the cold trap mechanism that protects H{sub 2}O on Earth is ineffective when the atmospheric inventory of non-condensing gases (e.g., N{sub 2}, Ar) is low. Hence the spectral features of O{sub 2} and O{submore » 3} alone cannot be regarded as robust signs of extraterrestrial life.« less

78 FR 54585 - Safety Zone; Escape to Miami Triathlon, Biscayne Bay, Miami, FL

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-05

.... Regulatory History and Information The Coast Guard is issuing this temporary final rule without prior notice... zones: 33 U.S.C. 1231; 46 U.S.C. Chapter 701, 3306, 3703; 50 U.S.C. 191, 195; 33 CFR 1.05-1, 6.04-1, 6....1. The purpose of the rule is to provide for the safety of life on navigable waters of the United...

77 FR 4897 - Safety Zone; M/V Del Monte Live-Fire Gun Exercise, James River, Isle of Wight, VA

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-01

...-AA00 Safety Zone; M/V Del Monte Live-Fire Gun Exercise, James River, Isle of Wight, VA AGENCY: Coast... provide for the safety of life on navigable waters during the live-fire gun exercises on the M/V Del Monte... associated with the live-fire gun exercise. DATES: This rule is effective in the CFR on February 1, 2012...

76 FR 31848 - Safety Zone; M/V Del Monte Live-Fire Gun Exercise, James River, Isle of Wight, Virginia

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-02

...-AA00 Safety Zone; M/V Del Monte Live-Fire Gun Exercise, James River, Isle of Wight, Virginia AGENCY... provide for the safety of life on navigable waters during the live-fire gun exercises on the M/V Del Monte... associated with the live-fire gun exercise. DATES: This rule will be effective from 11 a.m. June 6, 2011...

33 CFR 100.35T09-0327 - Special Regulated Areas for summer events; Captain of the Port Lake Michigan Zone.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Special Regulated Areas for summer events; Captain of the Port Lake Michigan Zone. 100.35T09-0327 Section 100.35T09-0327 Navigation... OF LIFE ON NAVIGABLE WATERS § 100.35T09-0327 Special Regulated Areas for summer events; Captain of...

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dayal, Pratika; Cockell, Charles; Rice, Ken

The field of astrobiology has made huge strides in understanding the habitable zones around stars (stellar habitable zones) where life can begin, sustain its existence and evolve into complex forms. A few studies have extended this idea by modeling galactic-scale habitable zones (galactic habitable zones) for our Milky Way (MW) and specific elliptical galaxies. However, estimating the habitability for galaxies spanning a wide range of physical properties has so far remained an outstanding issue. Here, we present a “cosmobiological” framework that allows us to sift through the entire galaxy population in the local universe and answer the question, “Which typemore » of galaxy is most likely to host complex life in the cosmos?” Interestingly, the three key astrophysical criteria governing habitability (total mass in stars, total metal mass and ongoing star formation rate) are found to be intricately linked through the “fundamental metallicity relation” as shown by Sloan Digital Sky Survey observations of more than a hundred thousand galaxies in the local universe. Using this relation we show that metal-rich, shapeless giant elliptical galaxies at least twice as massive as the MW (with a tenth of its star formation rate) can potentially host ten thousand times as many habitable (Earth-like) planets, making them the most probable “cradles of life” in the universe.« less

Fatigue Failure Modes of the Grain Size Transition Zone in a Dual Microstructure Disk

NASA Technical Reports Server (NTRS)

Gabb, Timothy P.; Kantzos, Pete T.; Palsa, Bonnie; Telesman, Jack; Gayda, John; Sudbrack, Chantal K.

2012-01-01

Mechanical property requirements vary with location in nickel-based superalloy disks. In order to maximize the associated mechanical properties, heat treatment methods have been developed for producing tailored grain microstructures. In this study, fatigue failure modes of a grain size transition zone in a dual microstructure disk were evaluated. A specialized heat treatment method was applied to produce varying grain microstructure in the bore to rim portions of a powder metallurgy processed nickel-based superalloy disk. The transition in grain size was concentrated in a zone of the disk web, between the bore and rim. Specimens were extracted parallel and transversely across this transition zone, and multiple fatigue tests were performed at 427 C and 704 C. Grain size distributions were characterized in the specimens, and related to operative failure initiation modes. Mean fatigue life decreased with increasing maximum grain size, going out through the transition zone. The scatter in limited tests of replicates was comparable for failures of uniform gage specimens in all transition zone locations examined.

Limit cycles at the outer edge of the habitable zone

NASA Astrophysics Data System (ADS)

Haqq-Misra, J. D.; Kopparapu, R.; Batalha, N. E.; Harman, C.; Kasting, J. F.

2016-12-01

The liquid water habitable zone (HZ) describes the orbital distance at which a terrestrial planet can maintain above-freezing conditions through regulation by the carbonate-silicate cycle. Calculations with one-dimensional climate models predict that the inner edge of the HZ is limited by water loss through a runaway greenhouse, while the outer edge of the HZ is bounded by the maximum greenhouse effect of carbon dioxide. This classic picture of the HZ continues to guide interpretation of exoplanet discoveries; however, recent calculations have shown that terrestrial planets near the outer edge of the HZ may exhibit other behaviors that affect their habitability. Here I discuss results from a hierarchy of climate models to understand the stellar environments most likely to support a habitable planet. I present energy balance climate model calculations showing the conditions under which planets in the outer regions of the habitable zone should oscillate between long, globally glaciated states and shorter periods of climatic warmth, known as `limit cycles.' Such conditions would be inimical to the development of complex land life, including intelligent life. Limit cycles may also provide an explanation for fluvial features on early Mars, although this requires additional greenhouse warming by hydrogen. These calculations show that the net volcanic outgassing rate and the propensity for plant life to sequester carbon dioxide are critical factors that determine the susceptibility of a planet to limit cycling. I argue that planets orbiting mid G- to mid K-type stars offer more opportunity for supporting advanced life than do planets around F-type stars or M-type stars.

Protecting into Emotion: Therapeutic Enactments with Military Veterans Transitioning Back into Civilian Life

ERIC Educational Resources Information Center

Balfoura, Michael; Westwood, Marvin; Buchanan, Marla J.

2014-01-01

Over 18.5% of military personnel returning from war zones to civilian life suffer mental health issues, which can lead to family breakdown, homelessness and other problems. Almost 4000 Australian soldiers have returned home from active service in the last decade suffering from combat stress and mental health conditions. A 2009 Australian…

77 FR 39633 - Special Local Regulation and Safety Zones; Marine Events in Captain of the Port Sector Long...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-05

... displays and swim events. This action is necessary to provide for the safety of life on navigable waters... order to provide for the safety of life on navigable waterways during regattas, fireworks displays and... the following events: Davis Park Fireworks, Charles W. Morgan Anniversary Fireworks and Waves of Hope...

Terrestrial Planet Finder Coronagraph overview of technology development & system design

NASA Technical Reports Server (NTRS)

Balasubramanian, Kunjuthapatham; Ford, Virginia; Mouroulis, Pantazis; Hoppe, Daniel; Shaklan, Stuart

2004-01-01

Astronomers have discovered over 150 planets orbiting other stars. NASA mission; Find and characterize terrestrial (or rocky) exo-planets that might harbor life (like Earth)liquid water on the planet (habitable zone). An atmosphere that indicates the presence of life water, oxygen, ozone, carbon dioxide, chlorophyll, and methane. Two missions under development: A coronagraph and an interferometer.

Genome-wide mapping in a house mouse hybrid zone reveals hybrid sterility loci and Dobzhansky-Muller interactions

PubMed Central

Turner, Leslie M; Harr, Bettina

2014-01-01

Mapping hybrid defects in contact zones between incipient species can identify genomic regions contributing to reproductive isolation and reveal genetic mechanisms of speciation. The house mouse features a rare combination of sophisticated genetic tools and natural hybrid zones between subspecies. Male hybrids often show reduced fertility, a common reproductive barrier between incipient species. Laboratory crosses have identified sterility loci, but each encompasses hundreds of genes. We map genetic determinants of testis weight and testis gene expression using offspring of mice captured in a hybrid zone between M. musculus musculus and M. m. domesticus. Many generations of admixture enables high-resolution mapping of loci contributing to these sterility-related phenotypes. We identify complex interactions among sterility loci, suggesting multiple, non-independent genetic incompatibilities contribute to barriers to gene flow in the hybrid zone. DOI: http://dx.doi.org/10.7554/eLife.02504.001 PMID:25487987

NanoSIMS isotope studies of rare types of presolar silicon carbide grains from the Murchison meteorite: Implications for supernova models and the role of 14C

NASA Astrophysics Data System (ADS)

Hoppe, Peter; Pignatari, Marco; Kodolányi, János; Gröner, Elmar; Amari, Sachiko

2018-01-01

We have conducted a NanoSIMS ion imaging survey of about 1800 presolar silicon carbide (SiC) grains from the Murchison meteorite. A total of 21 supernova (SN) X grains, two SN C grains, and two putative nova grains were identified. Six particularly interesting grains, two X and C grains each and the two putative nova grains were subsequently studied in greater detail, namely, for C-, N-, Mg-Al-, Si-, S-, and Ca-Ti-isotopic compositions and for the initial presence of radioactive 26Al (half life 716,000 yr), 32Si (half life 153 yr), and 44Ti (half life 60 yr). Their isotope data along with those of three X grains from the literature were compared with model predictions for 15 M⊙ and 25 M⊙ Type II supernovae (SNe). The best fits were found for 25 M⊙ SN models that consider for the He shell the temperature and density of a 15 M⊙ SN and ingestion of H into the He shell before the explosion. In these models a C- and Si-rich zone forms at the bottom of the He burning zone (C/Si zone). The region above the C/Si zone is termed the O/nova zone and exhibits the isotopic fingerprints of explosive H burning. Satisfactory fits of measured C-, N-, and Si-isotopic compositions and of 26Al/27Al ratios require small-scale mixing of matter originating from a region extending over 0.2 M⊙ for X and C grains and over 0.4 M⊙ for one of the putative nova grains, involving matter from a thin Si-rich layer slightly below the C/Si zone, the C/Si zone, and the O/nova zone. Simultaneous fitting of 14N/15N and 26Al/27Al requires a C-N fractionation of a factor of 50 during SiC condensation. This leads to preferential incorporation of radioactive 14C (half life 5700 yr) over directly produced 14N and can account for the 14N/15N along with 26Al/27Al ratios as observed in the SiC grains. The good fit for one of the putative nova grains along with its high 26Al/27Al points towards a SN origin and supports previous suggestions that some grains classified as nova grains might be from SNe. Apparent problems with the small-scale mixing scheme considered here are C/O ratios that are mostly <1 if C-, N-, and Si-isotopic compositions and 26Al/27Al ratios are simultaneously matched, underproduction of 32Si, and overproduction of 44Ti. This confirms the limitations of one-dimensional hydrodynamical models for H ingestion and stresses the need to better study the convective-boundary mixing mechanisms at the bottom of the convective He shell in massive star progenitors. This is crucial to define the effective size of the C/Si zone formed by the SN shock. The comparison between the Si isotope data of the SN grains and the models gives a hint that the predicted 30Si is too high at the bottom of the He burning shell.

The migrational patterns and developmental fates of glial precursors in the rat subventricular zone are temporally regulated.

PubMed

Levison, S W; Chuang, C; Abramson, B J; Goldman, J E

1993-11-01

Postnatal gliogenesis in the rodent forebrain was studied by infecting subventricular zone cells of either neonates or juvenile rats with replication-deficient retroviruses that encode reporter enzymes, enabling the migration and fate of these germinal zone cells to be traced over the ensuing several weeks. Neither neonatal nor juvenile subventricular zone cells migrated substantially along the rostral-caudal axis. Neonatal subventricular zone cells migrated dorsally and laterally into hemispheric gray and white matter and became both astrocytes and oligodendrocytes. Juvenile subventricular zone cells migrated into more medial areas of the subcortical white matter and on occasion appeared in the white matter of the contralateral hemisphere, but rarely migrated into the neocortex. Juvenile subventricular zone cells almost exclusively differentiated into oligodendrocytes. Thus, the migratory patterns and the developmental fates of subventricular zone cells change during the first 2 weeks of life. When either neonatal or juvenile subventricular zone cells were labeled in vivo and then removed and cultured, some generated homogeneous clones that contained either astrocytes with a 'type 1' phenotype or oligodendrocytes, but some generated heterogeneous clones that contained both glial types. These results provide additional evidence for a common progenitor for astrocytes and oligodendrocytes and strongly suggest that temporally and spatially regulated environmental signals control the destiny of glial progenitors during postnatal development.

Water in the critical zone: soil, water and life from profile to planet

NASA Astrophysics Data System (ADS)

Kirkby, M. J.

2016-12-01

Earth is unique in the combination of abundant liquid water, plate tectonics and life, providing the broad context within which the critical zone exists, as the surface skin of the land. Global differences in the availability of water provide a major control on the balance of processes operating in the soil, allowing the development of environments as diverse as those dominated by organic soils, by salty deserts or by deeply weathered lateritic profiles. Within the critical zone, despite the importance of water, the complexity of its relationships with the soil material continue to provide many fundamental barriers to our improved understanding, at the scales of pore, hillslope and landscape. Water is also a vital resource for the survival of increasing human populations. Intensive agriculture first developed in semi-arid areas where the availability of solar energy could be combined with irrigation water from more humid areas, minimising the problems of weed control with primitive tillage techniques. Today the challenge to feed the world requires improved, and perhaps novel, ways to optimise the combination of solar energy and water at a sustainable economic and environmental cost.

Risk factors and rate of progression for zone I versus zone II type 1 retinopathy of prematurity.

PubMed

Shin, Dong Hoon; Kong, Mingui; Kim, Sang Jin; Ham, Don Il; Kang, Se Woong; Chang, Yun Sil; Park, Won Soon

2014-04-01

To compare the risk factors and rate of progression of zone I versus zone II type 1 retinopathy of prematurity (ROP). The medical records of consecutive preterm infants with bilateral type 1 ROP in zone I and age-matched control infants with type 1 ROP in zone II were retrospectively analyzed. Fundus findings at each screening examination and systemic parameters were compared between groups. Univariate and conditional multivariate regression analyses were employed to identify variables significantly associated with zone I ROP. A total of 30 cases and 30 controls were included. The mean gestational age of included infants was 24.6 weeks in both groups, and the mean birth weights were 685 g in the zone I group and 667 g in the zone II group. The postmenstrual age (PMA) at the time of initial ROP detection did not differ between groups, but the PMA at the time of type 1 ROP detection was significantly earlier in the zone I group (mean, 34.9 vs 37.6 weeks). Conditional multiple logistic regression revealed that mechanical ventilation for 30 days or more was significantly associated with the type 1 ROP in zone I compared with zone II (OR, 3.5; 95% CI, 1.2-10.0). Zone I ROP exhibited rapid progression, necessitating close monitoring and prompt treatment. Compromised pulmonary function with associated mechanical ventilation in early life may restrict retinal vascular growth and increase the likelihood of zone I type 1 ROP. Copyright © 2014 American Association for Pediatric Ophthalmology and Strabismus. Published by Mosby, Inc. All rights reserved.

Pathways of nitrogen loss following land clearing in a humid tropical forest

NASA Technical Reports Server (NTRS)

Matson, Pamela; Vitousek, Peter

1985-01-01

Tropical deforestation generally leads to large losses of carbon and nitrogen. The Premontane Wet Forest Life Zone is subject to the highest rate of deforestation in Central America, and carbon and nutrient losses in from these fertile soils is very rapid and extreme. Losses of 2000 to 3000 kgN/ha have been reported. Losses of this magnitude could be extremely significant on a regional or global scale if even a small proportion of this nitrogen is lost as nitrous oxide to the atmosphere or through leaching of nitrate to rivers. This study seeks to measure the rates and regulation of nitrogen transformations, and the pathways of nitrogen losses following land clearing and burning at a site in the Premontane Wet Forest Life Zone near Turrialba, Costa Rica.

Transition to University Life: Insights from High School and University Female Students in Wolaita Zone, Ethiopia

ERIC Educational Resources Information Center

Thuo, Mary; Edda, Medhanit

2017-01-01

The purpose of this study was to get an insight about how high school female students perceive the transition to university life, and to understand the transition experience of university female students in the first semester. An exploratory study design was used where 166 high school female students and 88 first year university female students…

75 FR 26648 - Safety Zones; May Fireworks Displays Within the Captain of the Port Puget Sound Area of...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-12

... traffic is necessary to protect life, property and the environment. Discussion of Rule The U.S. Coast... Responsibility (AOR) AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The U.S Coast Guard is... necessary to provide for the safety of life on navigable waters during the fireworks displays. Entry into...

Optical Detection of Life on Exoplanets

NASA Technical Reports Server (NTRS)

Heap, Sara

2009-01-01

We describe what is known about the atmospheric properties (Teff, lob g, [FelH]) and fundamental properties (mass, age, and metal content) of nearby stars and how they influence the habitable zones and habitable eras of these stars. We then take an observer's point of view to assess the ability of optical telescopes to detect photosynthetic or methanogenic life on planets orbiting these stars.

Modulation of flagellum attachment zone protein FLAM3 and regulation of the cell shape in Trypanosoma brucei life cycle transitions

PubMed Central

Sunter, Jack D.; Benz, Corinna; Andre, Jane; Whipple, Sarah; McKean, Paul G.; Gull, Keith; Ginger, Michael L.; Lukeš, Julius

2015-01-01

ABSTRACT The cell shape of Trypanosoma brucei is influenced by flagellum-to-cell-body attachment through a specialised structure – the flagellum attachment zone (FAZ). T. brucei exhibits numerous morphological forms during its life cycle and, at each stage, the FAZ length varies. We have analysed FLAM3, a large protein that localises to the FAZ region within the old and new flagellum. Ablation of FLAM3 expression causes a reduction in FAZ length; however, this has remarkably different consequences in the tsetse procyclic form versus the mammalian bloodstream form. In procyclic form cells FLAM3 RNAi results in the transition to an epimastigote-like shape, whereas in bloodstream form cells a severe cytokinesis defect associated with flagellum detachment is observed. Moreover, we demonstrate that the amount of FLAM3 and its localisation is dependent on ClpGM6 expression and vice versa. This evidence demonstrates that FAZ is a key regulator of trypanosome shape, with experimental perturbations being life cycle form dependent. An evolutionary cell biology explanation suggests that these differences are a reflection of the division process, the cytoskeleton and intrinsic structural plasticity of particular life cycle forms. PMID:26148511

An Offshore Geophysical Network in the Pacific Northwest for Earthquake and Tsunami Early Warning and Hazard Research

NASA Astrophysics Data System (ADS)

Wilcock, W. S. D.; Schmidt, D. A.; Vidale, J. E.; Harrington, M.; Bodin, P.; Cram, G.; Delaney, J. R.; Gonzalez, F. I.; Kelley, D. S.; LeVeque, R. J.; Manalang, D.; McGuire, C.; Roland, E. C.; Tilley, J.; Vogl, C. J.; Stoermer, M.

2016-12-01

The Cascadia subduction zone hosts catastrophic earthquakes every few hundred years. On land, there are extensive geophysical networks available to monitor the subduction zone, but since the locked portion of the plate boundary lies mostly offshore, these networks are ideally complemented by seafloor observations. Such considerations helped motivate the development of scientific cabled observatories that cross the subduction zone at two sites off Vancouver Island and one off central Oregon, but these have a limited spatial footprint along the strike of the subduction zone. The Pacific Northwest Seismic Network is leading a collaborative effort to implement an earthquake early warning system in the Washington and Oregon using data streams from land networks as well as the few existing offshore instruments. For subduction zone earthquakes that initiate offshore, this system will provide a warning. However, the availability of real time offshore instrumentation along the entire subduction zone would improve its reliability and accuracy, add up to 15 s to the warning time, and ensure an early warning for coastal communities near the epicenter. Furthermore, real-time networks of seafloor pressure sensors above the subduction zone would enable monitoring and contribute to accurate predictions of the incoming tsunami. There is also strong scientific motivation for offshore monitoring. We lack a complete knowledge of the plate convergence rate and direction. Measurements of steady deformation and observations of transient processes such as fluid pulsing, microseismic cycles, tremor and slow-slip are necessary for assessing the dimensions of the locked zone and its along-strike segmentation. Long-term monitoring will also provide baseline observations that can be used to detect and evaluate changes in the subduction environment. There are significant engineering challenges to be solved to ensure the system is sufficiently reliable and maintainable. It must provide continuous monitoring over its operational life in the harsh ocean environment and at least parts of the system must continue to operate following a megathrust event. These requirements for robustness must be balanced with the desire for a flexible design that can accommodate new scientific instrumentation over the life of the project.

Radiative Convective Transfer Calculations for Effective Stellar Fluxes of Habitable and Life Supporting Zones

NASA Astrophysics Data System (ADS)

Ludwig, Wolfgang; Eggl, Siegfried; Neubauer, David; Leitner, Johannes; Firneis, Maria; Hitzenberger, Regina

2014-05-01

Recent fields of interest in exoplanetary research include studies of potentially habitable planets orbiting stars outside of our Solar System. Habitable Zones (HZs) are currently defined by calculating the inner and the outer limits of the mean distance between exoplanets and their central stars based on effective solar fluxes that allow for maintaining liquid water on the planet's surface. Kasting et al. (1993), Selsis et al. (2007), and recently Kopparapu et al. (2013) provided stellar flux limits for such scenarios. We compute effective solar fluxes for Earth-like planets using Earth-like and other atmospheric scenarios including atmospheres with high level and low level clouds. Furthermore we provide habitability limits for solvents other than water, i.e. limits for the so called Life Supporting Zone, introduced by Leitner et al. (2010). The Life Supporting Zone (LSZ) encompasses many habitable zones based on a variety of liquid solvents. Solvents like ammonia and sulfuric acid have been identified for instance by Leitner et al (2012) as possibly life supporting. Assuming planets on circular orbits, the extent of the individual HZ is then calculated via the following equation, d(i,o) = [L/Lsun*1/S(i,o)]**0.5 au, where L is the star's luminosity, and d(i,o) and S(i,o) are the distances to the central star for the inner and the outer edge and effective insolation for inner and the outer edge of the HZ, respectively. After generating S(i,o) values for a selection of solvents, we provide the means to determine LSZ boundaries for main sequence stars. Effective flux calculations are done using a one dimensional radiative convective model (Neubauer et al. 2011) based on a modified version of the open source radiative transfer software Streamer (Key and Schweiger, 1998). Modifications include convective adjustments, additional gases for absorption and the use of an offline cloud model, which allow us to observe the influence of clouds on effective stellar fluxes. Kasting, J.F., Whitmire, D.P., & Reynolds, R.T. 1993, Icar, 101, 108 Key JR, Schweiger AJ (1998) Geosci 24:443-451. Kopparapu, R.J., et al. 2013 ApJ 765, 131 Leitner, J. J., Schwarz, R., Firneis, M. G., Hitzenberger, R., and Neubauer, D., Astrobiology Science Conference 2010, 26-29 April 2010, League City, USA, 2010 Leitner, J.J., Schulze-Makuch, D., Firneis, M.G., Hitzenberger, R., Neubauer, D., 2012 Paleontology Journal 46 (9), 1091 Neubauer, D., Vrtala, A., Leitner, J.J., Firneis, M.G., Hitzenberger, R., 2011 Origins of Life and Evolution of Biospheres, 41, 545-552 Selsis, F., Kasting, J.F., Levrard, B., et al. 2007b, A&A, 476, 137

Public secondary school teachers' attitude to family life education in two geopolitical zones of Nigeria: a comparative analysis.

PubMed

Okusanya, B O; Isabu, P A

2010-03-01

This qualitative study was conducted to assess and compare the attitude of teachers in two geopolitical zones of Nigeria to family life education. Multi stage sample selection was used to pick 6 public secondary schools (3 junior, 3 senior) in each zone. All teachers (221) in the selected schools were surveyed. Pre-tested questionnaires were self administered, responses analyzed and results presented using descriptive frequencies. Where appropriate statistical evaluation was done with Yates corrected Chi square at 95% confidence interval. Katsina respondents were mostly Muslims (92.4%), married (64.8%) and had the National Certificate of Education (62.9%). Ekpoma teachers were mostly Christians (97.4%), married (93.1%) and 67.2% had a University degree. Attendance at a seminar on family life education was by 19% and 25.9% of respondents from Katsina and Ekpoma respectively. Teachers' knowledge of family life education was very good and most teachers in both regions considered it useful but there were geographical disparities in perception and attitude. While teachers in Katsina discussed HIV/AIDS twice more with their students than sexuality (54.3% vs 28%) those in Ekpoma discussed sexuality more than HIV/AIDS (80.2% vs 72.4%). Respondents in Katsina reported three times (60% vs 19.8%) more that parents would object to FLE in schools than those in Ekpoma and also that its introduction would encourage promiscuity amongst the students (53.3% vs 21.6%). While being married positively influenced respondents' perception, their attitude was influenced positively by having university degree and teaching at the senior secondary school. Christians significantly discussed sexuality (Chi square 58.60; RR: 3.03) and HIV/AIDS (Chi square 15.01; RR: 1.50) with students than Muslims. Policy makers need to be aware of the regional differences in teachers' attitude to family life education as this may hinder the implementation of curriculum.

77 FR 19963 - Special Local Regulation and Security Zone: War of 1812 Bicentennial Commemoration, Port of...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-03

...The Coast Guard proposes to adopt a temporary special local regulation and temporary security zones, during, and after the War of 1812 Bicentennial Commemoration events in the Port of Boston, Massachusetts, to be held between June 28, 2012 and July 6, 2012. These regulations are necessary to promote the safe navigation of vessels and the safety of life and property during the heavy volume of vessel traffic expected during this event.

Performance of thermal sprayed aluminium coatings in the splash zone and for riser service

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fischer, K.P.; Rosbrook, T.; Thomason, W.H.

1994-12-31

Historically, the coatings used in the splash zone have been either heavy duty coal tar epoxy or a glassflake epoxy. In 1982 Conoco justified a minimum 20 year service life for a sealed thermal sprayed aluminium (TSA) coating for the Hutton TLP risers and tethers. In 1984 the Hutton TLP was installed with 200 microns thickness TSA as the corrosion protection coating and without adding a corrosion allowance. After eight years service the TSA coating on the production risers and tethers is still in good condition. It was noted that the splash zone area was indistinguishable from the remainder ofmore » the inspected components. However, there was a noticeable difference between the production risers and the tethers. The tethers having a vinyl sealer showed a blistered surface while the risers with a silicone sealer did not show any blistering. No corrosion has been observed underneath any of the blisters. The importance of adequate sealers in connection with blistering has been documented by testing. The excellent long term performance of TSA coating in the splash zone has been further documented by the results of field studies published in the last few years. These experiences indicate that TSA coatings properly applied and with the use of specific sealer systems may provide a service life in excess of 30 years with no required maintenance.« less

Oxygen in the deep-sea: The challenge of maintaining uptake rates in a changing ocean

NASA Astrophysics Data System (ADS)

Hofmann, A. F.; Peltzer, E. T.; Brewer, P. G.

2011-12-01

Although focused on recently, ocean acidification is not the only effect of anthropogenic CO2 emissions on the ocean. Ocean warming will reduce dissolved oxygen concentrations and at the hypoxic limit for a given species this can pose challenges to marine life. The limit is traditionally reported simply as the static mass concentration property [O2]; here we treat it as a dynamic gas exchange problem for the animal analogous to gas exchange at the sea surface. The diffusive limit and its relationship to water velocity is critical for the earliest stages of marine life (eggs, embryos), but the effect is present for all animals at all stages of life. We calculate the external limiting O2 conditions for several representative metabolic rates and their relationship to flow of the bulk fluid under different environmental conditions. Ocean O2 concentrations decline by ≈ 14 μmol kg-1 for a 2 °C rise in temperature. At standard 1000 m depth conditions in the Pacific, flow over the surface would have to increase by ≈ 60% from 2.0 to 3.2 cm s-1 to compensate for this change. The functions derived allow new calculations of depth profiles of limiting O2 concentrations, as well as maximal diffusively sustainable metabolic oxygen consumption rates at various places around the world. Our treatment shows that there is a large variability in the global ocean in terms of facilitating aerobic life. This variability is greater than the variability of the oxygen concentration alone. It becomes clear that temperature and pressure dependencies of diffusion and partial pressure create a region typically around 1000 m depth where a maximal [O2] is needed to sustain a given metabolic rate. This zone of greatest physical constriction on the diffusive transport in the boundary layer is broadly consistent with the oxygen minimum zone, i.e., the zone of least oxygen concentration supply, resulting in a pronounced minimum of maximal diffusively sustainable metabolic oxygen consumption rates. This least-favorable zone for aerobic respiration is bound to expand with further ocean warming.

Component testing of a ground based gas turbine steam cooled rich-burn primary zone combustor for emissions control of nitrogeneous fuels

NASA Technical Reports Server (NTRS)

Schultz, D. F.

1986-01-01

This effort summarizes the work performed on a steam cooled, rich-burn primary zone, variable geometry combustor designed for combustion of nitrogeneous fuels such as heavy oils or synthetic crude oils. The steam cooling was employed to determine its feasibility and assess its usefulness as part of a ground based gas turbine bottoming cycle. Variable combustor geometry was employed to demonstrate its ability to control primary and secondary zone equivalence ratios and overall pressure drop. Both concepts proved to be highly successful in achieving their desired objectives. The steam cooling reduced peak liner temperatures to less than 800 K. This low temperature offers the potential of both long life and reduced use of strategic materials for liner fabrication. These degrees of variable geometry were successfully employed to control air flow distribution within the combustor. A variable blade angle axial flow air swirler was used to control primary zone air flow, while the secondary and tertiary zone air flows were controlled by rotating bands which regulated air flow to the secondary zone quench holes and the dilutions holes respectively.

Economic regionalization and choice of strategic development directions of municipalities of the Republic of Tatarstan

NASA Astrophysics Data System (ADS)

Panasyuk, M. V.

2018-01-01

This paper shows the results of economic regionalization and zoning of the Republic of Tatarstan, conducted in 2017. The latest experience of economic regionalization and zoning of the Republic of Tatarstan in 2007 - 2015 is exposed. The economic regionalization problem is solved on the basis of new method and algorithm that uses quantitative measures which characterize spatial and economic features of generated economic regions including their internal and average connectivity, homogeneity, compactness, socio-economic development level and life quality of the population. Three nodal and one homogeneous economic region in the Republic of Tatarstan were identified. The results of economic zoning within homogeneous economic region led to the conclusion about two existing economic zones. They have the potential for developing new economic growth pole and three economic centers - growth points with specialization on agro-industrial sector.

The reaction of chlorobenzene with plasma of H2O, CO2 and CH4 obtained by an alternating-current plasma torch with a vortex stabilization

NASA Astrophysics Data System (ADS)

Surov, A. V.; Subbotin, D. I.; Obraztsov, N. V.; Popov, S. D.; Popov, V. E.; Litvyakova, A. I.; Pavlov, A. V.; Serba, E. O.; Spodobin, V. A.; Nakonechny, Gh V.

2018-01-01

This paper presents the three-phase ac plasma torch with a vortex stabilization of the arc, and two inputs of plasma environments: the electrode zone and the arc zone. Shielding gas (carbon dioxide) is supplied in the electrode zone and steam, methane and vapor of chlorobenzene are fed in the arc zone. By means of it the life time of electrodes is increased significantly. Chlorobenzene is selected, as it is the simplest aromatic chlorine-containing substance. The chemical process flows in two pathways: the formation of synthesis gas and the formation of soot. The gaseous chlorine-containing compound was only hydrogen chloride, yield of soot was 0.98% by weight of the raw materials, and the chlorine content was 2.08 wt% by the soot.

The abundance of biotic exoplanets and life on planets of Red Dwarf stars

NASA Astrophysics Data System (ADS)

Wandel, Amri; Gale, Joseph

2016-07-01

The Kepler mission has shown that Earthlike planets orbiting within the Habitable Zones of their host stars are common. We derive an expression for the abundance of life bearing (biotic) extra-solar-system planets (exoplanets) in terms of the (yet unknown) probability for the evolution of biotic life. This "biotic probability" may be estimated by future missions and observations, e.g. spectral analyses of the atmospheres of exoplanets, looking for biomarkers. We show that a biotic probability in the range 0.001-1 implies that a biotic planet may be expected within ~10-100 light years from Earth. Of particular interest in the search for exolife are planets orbiting Red Dwarf (RD) stars, the most frequent stellar type. Previous researches suggested that conditions on planets near RDs would be inimical to life, e.g. the Habitable Zone of RDs is small, so their habitable planets would be close enough to be tidally locked. Recent calculations show that this and other properties of RDs, presumed hostile for the evolution of life, are less severe than originally estimated. We conclude that RD planets could be hospitable for the evolution of life as we know it, not less so than planets of solar-type stars. This result, together with the large number of RDs and their Kepler planet-statistics, makes finding life on RD planets ~10-1000 times more likely than on planets of solar-type stars. Our nearest biotic RD-planet is likely to be 2-10 times closer than the nearest solar-type one.

Leadership Begins at the End of Your Comfort Zone

ERIC Educational Resources Information Center

Ryder, Marilou

2013-01-01

The path one chooses in life may not always be an easy one. Through simple acts of failure and disappointment, the author learned a lot about her inspiration to become a leader and what it actually took to make them a reality. As a woman who had little confidence to handle major life changes, the author values every second of the experience.…

Supporting Distributed Team Working in 3D Virtual Worlds: A Case Study in Second Life

ERIC Educational Resources Information Center

Minocha, Shailey; Morse, David R.

2010-01-01

Purpose: The purpose of this paper is to report on a study into how a three-dimensional (3D) virtual world (Second Life) can facilitate socialisation and team working among students working on a team project at a distance. This models the situation in many commercial sectors where work is increasingly being conducted across time zones and between…

33 CFR 100.100 - Special Local Regulations; Regattas and Boat Races in the Coast Guard Sector Long Island Sound...

Code of Federal Regulations, 2013 CFR

2013-07-01

...; Regattas and Boat Races in the Coast Guard Sector Long Island Sound Captain of the Port Zone. 100.100... MARINE PARADES SAFETY OF LIFE ON NAVIGABLE WATERS § 100.100 Special Local Regulations; Regattas and Boat... any time it is deemed necessary to ensure the safety of life or property. (i) For all power boat races...

33 CFR 100.100 - Special Local Regulations; Regattas and Boat Races in the Coast Guard Sector Long Island Sound...

Code of Federal Regulations, 2012 CFR

2012-07-01

...; Regattas and Boat Races in the Coast Guard Sector Long Island Sound Captain of the Port Zone. 100.100... MARINE PARADES SAFETY OF LIFE ON NAVIGABLE WATERS § 100.100 Special Local Regulations; Regattas and Boat... it is deemed necessary to ensure the safety of life or property. (i) For all power boat races listed...

33 CFR 100.100 - Special Local Regulations; Regattas and Boat Races in the Coast Guard Sector Long Island Sound...

Code of Federal Regulations, 2014 CFR

2014-07-01

...; Regattas and Boat Races in the Coast Guard Sector Long Island Sound Captain of the Port Zone. 100.100... MARINE PARADES SAFETY OF LIFE ON NAVIGABLE WATERS § 100.100 Special Local Regulations; Regattas and Boat... any time it is deemed necessary to ensure the safety of life or property. (i) For all power boat races...

Synaptic organization of the Drosophila antennal lobe and its regulation by the Teneurins

PubMed Central

Mosca, Timothy J; Luo, Liqun

2014-01-01

Understanding information flow through neuronal circuits requires knowledge of their synaptic organization. In this study, we utilized fluorescent pre- and postsynaptic markers to map synaptic organization in the Drosophila antennal lobe, the first olfactory processing center. Olfactory receptor neurons (ORNs) produce a constant synaptic density across different glomeruli. Each ORN within a class contributes nearly identical active zone number. Active zones from ORNs, projection neurons (PNs), and local interneurons have distinct subglomerular and subcellular distributions. The correct number of ORN active zones and PN acetylcholine receptor clusters requires the Teneurins, conserved transmembrane proteins involved in neuromuscular synapse organization and synaptic partner matching. Ten-a acts in ORNs to organize presynaptic active zones via the spectrin cytoskeleton. Ten-m acts in PNs autonomously to regulate acetylcholine receptor cluster number and transsynaptically to regulate ORN active zone number. These studies advanced our ability to assess synaptic architecture in complex CNS circuits and their underlying molecular mechanisms. DOI: http://dx.doi.org/10.7554/eLife.03726.001 PMID:25310239

[The characteristics of population health in social ecological conditions of the Primorskiĭ Kraĭ].

PubMed

Iarygina, M V; Kiku, P F; Gorborukova, T V; Iudin, S S

2013-01-01

The article presents the results of sociological survey of residents of different bioclimatic zones of urbanized and rural territories of different bioclimatic zones of the Primorsky Kraiy in municipalities with different demographic, ecological and social characteristics. The analysis of survey data using the technique of P.V. Terentiyev correlation pleiades was applied. The relationship was established between a number of such factors as social industrial environment, ecological condition of territory of residence, life-style and climate with population health.

NASA's Kepler Mission Discovers Its Smallest Habitable Zone Planets (Reporter Pkg)

NASA Image and Video Library

2013-04-18

NASA's Kepler mission has discovered two new planetary systems that include three super-Earth-size planets in the 'habitable zone,' the range of distance from a star where the surface temperature of an orbiting planet might be suitable for liquid water. Scientists do not know whether life could exist on the newfound planets, but their discovery signals we are another step closer to finding a world similar to Earth around a star like our sun. Kepler-62 and -69 systems

Marine biology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thurman, H.V.; Webber, H.H.

1984-01-01

This book discusses both taxonomic and ecological topics on marine biology. Full coverage of marine organisms of all five kingdoms is provided, along with interesting and thorough discussion of all major marine habitats. Organization into six major parts allows flexibility. It also provides insight into important topics such as disposal of nuclear waste at sea, the idea that life began on the ocean floor, and how whales, krill, and people interact. A full-color photo chapter reviews questions, and exercises. The contents are: an overview marine biology: fundamental concepts/investigating life in the ocean; the physical ocean, the ocean floor, the naturemore » of water, the nature and motion of ocean water; general ecology, conditions for life in the sea, biological productivity and energy transfer; marine organisms; monera, protista, mycota and metaphyta; the smaller marine animals, the large animals marine habitats, the intertidal zone/benthos of the continental shelf, the photic zone, the deep ocean, the ocean under stress, marine pollution, appendix a: the metric system and conversion factors/ appendix b: prefixes and suffixes/ appendix c: taxonomic classification of common marine organisms, and glossary, and index.« less

USAF Damage Tolerant Design Handbook: Guidelines for the Analysis and Design of Damage Tolerant Aircraft Structures. Revision B

DTIC Science & Technology

1984-05-01

Effect of Block Programming and Block Size on Crack Growth Life (All Histories Have Same Cycle Content) Alloy : 2024 -T3 Aluminum (Reference 27...1 I 6 o T 1 >0 100 Crack Growth Life for l-in. Crack Growth 1000 Figure 5.1.10, Effect of Humidity on Fatigue Crack Propagation...Growth Life (All Histories Have Same Cycle Content) Alloy : 2024 -T3 Aluminum (Reference 27). 5.2.6 Yield Zone Due to Overload (r T), Current Crack

The planets and life.

NASA Technical Reports Server (NTRS)

Young, R. S.

1971-01-01

It is pointed out that planetary exploration is not simply a program designed to detect life on another planet. A planet similar to earth, such as Mars, when studied for evidence as to why life did not arise, may turn out to be scientifically more important than a planet which has already produced a living system. Of particular interest after Mars are Venus and Jupiter. Jupiter has a primitive atmosphere which may well be synthesizing organic molecules today. Speculations have been made concerning the possibility of a bio-zone in the upper atmosphere of Venus.

UV habitable zones around M stars

NASA Astrophysics Data System (ADS)

Buccino, Andrea P.; Lemarchand, Guillermo A.; Mauas, Pablo J. D.

2007-12-01

During the last decade there was a change in paradigm, which led to consider that terrestrial-type planets within liquid-water habitable zones (LW-HZ) around M stars can also be suitable places for the emergence and evolution of life. Since many dMe stars emit large amount of UV radiation during flares, in this work we analyze the UV constrains for living systems on Earth-like planets around dM stars. We apply our model of UV habitable zone (UV-HZ; Buccino, A.P., Lemarchand, G.A., Mauas, P.J.D., 2006. Icarus 183, 491-503) to the three planetary systems around dM stars (HIP 74995, HIP 109388 and HIP 113020) observed by IUE and to two M-flare stars (AD Leo and EV Lac). In particular, HIP 74995 hosts a terrestrial planet in the LW-HZ, which is the exoplanet that most resembles our own Earth. We show, in general, that during the quiescent state there would not be enough UV radiation within the LW-HZ to trigger the biogenic processes and that this energy could be provided by flares of moderate intensity, while strong flares do not necessarily rule-out the possibility of life-bearing planets.

Climate regulation, energy provisioning and water purification: Quantifying ecosystem service delivery of bioenergy willow grown on riparian buffer zones using life cycle assessment.

PubMed

Styles, David; Börjesson, Pål; D'Hertefeldt, Tina; Birkhofer, Klaus; Dauber, Jens; Adams, Paul; Patil, Sopan; Pagella, Tim; Pettersson, Lars B; Peck, Philip; Vaneeckhaute, Céline; Rosenqvist, Håkan

2016-12-01

Whilst life cycle assessment (LCA) boundaries are expanded to account for negative indirect consequences of bioenergy such as indirect land use change (ILUC), ecosystem services such as water purification sometimes delivered by perennial bioenergy crops are typically neglected in LCA studies. Consequential LCA was applied to evaluate the significance of nutrient interception and retention on the environmental balance of unfertilised energy willow planted on 50-m riparian buffer strips and drainage filtration zones in the Skåne region of Sweden. Excluding possible ILUC effects and considering oil heat substitution, strategically planted filter willow can achieve net global warming potential (GWP) and eutrophication potential (EP) savings of up to 11.9 Mg CO 2 e and 47 kg PO 4 e ha -1 year -1 , respectively, compared with a GWP saving of 14.8 Mg CO 2 e ha -1 year -1 and an EP increase of 7 kg PO 4 e ha -1 year -1 for fertilised willow. Planting willow on appropriate buffer and filter zones throughout Skåne could avoid 626 Mg year -1 PO 4 e nutrient loading to waters.

75 FR 34365 - Safety Zone, Alligator River, NC

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-17

... interest, since immediate action is needed to ensure the safety of human life and property from the hazards... do not individually or cumulatively have a significant effect on the human environment. This rule is...

75 FR 29695 - Security Zones; Sabine Bank Channel, Sabine Pass Channel and Sabine-Neches Waterway, TX

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-27

... regime designed to safeguard human life, vessels, and waterfront facilities against sabotage or terrorist... effect on the human environment. A preliminary environmental analysis checklist supporting this...

76 FR 53337 - Special Local Regulation and Safety Zones; Marine Events in Captain of the Port Long Island Sound...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-26

... action is necessary to provide for the safety of life on navigable waters during the events. Entry into... Waves of Hope Swim, Stonewall Swim, Hartford Dragon Boat Races and Kayak for a Cause have hundreds of... safety of life during this year's event. For the same reasons, under 5 U.S.C. 553(d)(3), the Coast Guard...

Flaw characterization through nonlinear ultrasonics and wavelet cross-correlation algorithms

NASA Astrophysics Data System (ADS)

Bunget, Gheorghe; Yee, Andrew; Stewart, Dylan; Rogers, James; Henley, Stanley; Bugg, Chris; Cline, John; Webster, Matthew; Farinholt, Kevin; Friedersdorf, Fritz

2018-04-01

Ultrasonic measurements have become increasingly important non-destructive techniques to characterize flaws found within various in-service industrial components. The prediction of remaining useful life based on fracture analysis depends on the accurate estimation of flaw size and orientation. However, amplitude-based ultrasonic measurements are not able to estimate the plastic zones that exist ahead of crack tips. Estimating the size of the plastic zone is an advantage since some flaws may propagate faster than others. This paper presents a wavelet cross-correlation (WCC) algorithm that was applied to nonlinear analysis of ultrasonically guided waves (GW). By using this algorithm, harmonics present in the waveforms were extracted and nonlinearity parameters were used to indicate both the tip of the cracks and size of the plastic zone. B-scans performed with the quadratic nonlinearities were sensitive to micro-damage specific to plastic zones.

Population morbidity in the Zaporizhzhia Nuclear Power Plant observation zone as an integral part of public health.

PubMed

Khomenko, I M; Zakladna, N V; Orlova, N M

2017-12-01

To evaluate the health status of adult population living in the Ukrainian nuclear power industry obser vation zone on the example of Zaporizhzhia Nuclear Power Plant. System review, analytic, sociological survey and statistical methods. There was established an increase in the incidence of digestive diseases among adult population in Nikopol of Dnipropetrovsk region, which is included in the Zaporizhzhia NPP observation zone. The highest increase was observed in the incidence of peptic ulcer, gastritis and duodenitis, cholecystitis and cholangitis by 340 %, 305 % and 83 %, respectively. In connection with the residence in industrially developed region and NPP life extension in Ukraine, the possible influence of harmful factors on health status of the population of observation zones, an increase in the incidence of digestive diseases among adult population, there is required continuous monitoring and detailed study of public health. I. M. Khomenko, N. V. Zakladna, N. M. Orlova.

[Evaluation of sustainable development of Dalian Economic and Technological Development Zone based on MuSIASEM theory].

PubMed

Geng, Yong; Liu, Xiao-qing; Zhang, Pan; Liu, Ye

2010-10-01

Based on the theory of multiple-scale integrated assessment of societal and ecosystem metabolism (MuSIASEM), a comprehensive evaluation was made on the human activity time, exosomatic energy input, and added value of Dalian Economic and Technological Development Zone in 2000-2007. During the study period, the life quality of local citizens increased year after year, while the agricultural industry dwindled. Manufacturing industry was still the main pillar industry, but its energy consumption was greater. Service industry was at its early stage, falling behind manufacturing industry. The exosomatic metabolic level of the whole zone and its various industries had an obvious increase, and the energy intensity decreased continuously. With the fact that both the human activity time and the exosomatic energy input had a ceaseless decrease, the economic added value increased steadily, and the zone was under its way towards sustainable development.

Where Should We Look for Life?

NASA Astrophysics Data System (ADS)

Kohler, Susanna

2018-04-01

The first challenge in the hunt for life elsewhere in our universe is to decide where to look. In a new study, two scientists examine whether Sun-like stars or low-mass M dwarfs are the best bet for hosting exoplanets with detectable life.Ambiguity of HabitabilityThe habitable zones of cool M-dwarf stars lie much closer in than for Sun-like stars, placing habitable-zone planets around M dwarfs at greater risk of being affected by space weather.Most exoplanet scientists will freely admit frustration with the term habitability its a word that has many different meanings and is easily misinterpreted when it appears in news articles. Just because a planet lies in a stars habitable zone, for instance, doesnt mean its necessarily capable of supporting life.This ambiguity, argue authors Manasvi Lingam and Abraham Loeb (Harvard University and Harvard-Smithsonian Center for Astrophysics), requires us to take a strategic approach when pursuing the search for primitive life outside of our solar system. In particular, we risk losing the enthusiasm and support of the public (and funding sources!) when wefocus on the general search for planets in stellar habitable zones, rather than specifically searching for the planets most likely to have detectable signatures of life.Illustration of the difference between a Sun-like star and a lower-mass, cooler M-dwarf star. [NASAs Goddard Space Flight Center/S. Wiessinger]Weighing Two TargetsSo how do we determine where best to look for planets with detectable biosignatures? To figure out which stars make the optimal targets, Lingam and Loeb suggest an approach based on standard cost-benefit analyses common in economics. Here, whats being balanced is the cost of an exoplanet survey mission against the benefit of different types of stellar targets.In particular, Lingam and Loeb weigh the benefit of targeting solar-type stars against that of targeting stars of any other mass (such as low-mass M-dwarfs, popular targets of many current exoplanet surveys). The advantage of one type of target over the other depends on two chief factors:the probability that the targeted star hosts planets with life, andthe probability that biosignatures arising from this life are detectable, given our available technology.Promise of Sun-Like StarsRelative benefit of searching for signatures of life around stars with varying masses, assuming a transmission spectroscopy survey mission; results are similar for a direct-imaging mission. Green curve assumes a flat prior; red and blue curves assume priors in which habitability is suppressed around low-mass stars. [Lingam Loeb 2018]Taking observational constraints into account, Lingam and Loebs results depend on what is known in statistics as a prior an assumption that goes into the calculation. The two possible outcomes are:If we assume a flat prior i.e., that the probability of life is the same for any choice of star then searching for life around M-dwarfs proves the most advantageous, because the detection of biosignatures becomes much easier.If we assume a prior in which habitability is suppressed around low-mass stars, then it is more advantageous to search for life around solar-type stars.So which of these priors is correct? There is mounting evidence, particularly based on considerations of space weather, that the habitability of Earth-like planets around M dwarfs might be much lower than their counterparts around solar-like stars.If this turns out to be true, then Lingam and Loeb argue exoplanet survey missions should target Sun-like stars throughout our galaxy for the best chances of efficiently detecting life beyond our solar system.CitationManasvi Lingam and Abraham Loeb 2018 ApJL 857 L17. doi:10.3847/2041-8213/aabd86

A New Method for the Quick Determination of S-Type and P-Type Habitable Zones in Binary Systems

NASA Astrophysics Data System (ADS)

Wang, Zhaopeng; Cuntz, Manfred

2017-01-01

More than 3500 exoplanets have been confirmed nowadays, including a very large number of planets discovered by the Kepler mission. Additional exoplanets are expected to be found by ongoing missions as, e.g., K2 as well as future missions such as TESS. Exoplanets, especially terrestrial planets, located in stellar habitable zones are drawing great attention from the community and the public at large due to their potential for hosting alien life - a prospect that makes the adequate determination of stellar habitable zones an important goal of exoplanetary research. In the local Galactic neighborhood, binary systems occur relatively frequently. Thus, it is the aim of my presentation to offer a method for the quick determination for the existence of habitable zones in binaries. Therefore, fitting formulas for binary habitable zones regarding both S-type and P-type star-planet configurations are provided. Based on previous work in the literature, a joint constraint regarding radiative habitable zones and planetary orbital stability limits is used. Models of stellar habitable zones utilize updated computations for planetary climate models as given by Kopparapu et al. (2013, 2014) [ApJ 765, 131; ApJL 787, L29]. Cases studies showing the quality of the fit formulas, as well as applications to observed systems, are presented as well.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lucash, M.S.; Farnsworth, B.; Winner, W.E.

This study tests the potential for interactions between root-zone temperature and CO{sub 2} for plants which co-occur in a habitat where root-zone temperature fluctuate throughout the day. Controlled environment studies were conducted to expose desert plants to combinations of low or high root zone temperatures and low or high CO{sub 2}. Artemisia tridentata, Sitanion hystrix, and Stipa thurberiana were chosen for study to represent eastern Oregon plants that differ in their life history strategies. Seeds were planted in pots containing native soils and were grown in environmentally controlled growth chambers for three months. Growth treatments were either ambient (380 ppm)more » or high (580 ppm) CO{sub 2} concentration and high (18{degrees}C) or low (13{degrees} C) root-zone temperature. A. tridentata (a perennial shrub) was relatively unresponsive to treatments. Growth of S. hystrix and S. thurberiana (both C{sub 3} grasses) was stimulated by root-zone warming at both ambient and elevated CO{sub 2} levels. CO{sub 2} stimulated growth occurred for both grass species at low root-zone temperatures but only for S. thurberiana at high root-zone temperatures. Biomass increases from elevated CO{sub 2} were enhanced by root-zone warming indicating treatment interactions. Leaf-level photosynthesis measurements were consistent across species, but could not explain growth responses to treatments. These studies indicate that grasses may be more responsive to environmental change than co-occurring shrubs.« less

Metagenomic insights into important microbes from the Dead Zone

NASA Astrophysics Data System (ADS)

Thrash, C.; Baker, B.; Seitz, K.; Temperton, B.; Gillies, L.; Rabalais, N. N.; Mason, O. U.

2015-12-01

Coastal regions of eutrophication-driven oxygen depletion are widespread and increasing in number. Also known as dead zones, these regions take their name from the deleterious effects of hypoxia (dissolved oxygen less than 2 mg/L) on shrimp, demersal fish, and other animal life. Dead zones result from nutrient enrichment of primary production, concomitant consumption by chemoorganotrophic aerobic microorganisms, and strong stratification that prevents ventilation of bottom water. One of the largest dead zones in the world occurs seasonally in the northern Gulf of Mexico (nGOM), where hypoxia can reach up to 22,000 square kilometers. While this dead zone shares many features with more well-known marine oxygen minimum zones, it is nevertheless understudied with regards to the microbial assemblages involved in biogeochemical cycling. We performed metagenomic and metatranscriptomic sequencing on six samples from the 2013 nGOM dead zone from both hypoxic and oxic bottom waters. Assembly and binning led to the recovery of over fifty partial to nearly complete metagenomes from key microbial taxa previously determined to be numerically abundant from 16S rRNA data, such as Thaumarcheaota, Marine Group II Euryarchaeota, SAR406, SAR324, Synechococcus spp., and Planctomycetes. These results provide information about the roles of these taxa in the nGOM dead zone, and opportunities for comparing this region of low oxygen to others around the globe.

77 FR 63734 - Security Zone; James River, Kingsmill Resort, Williamsburg, VA

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-17

... attacks to human life, vessels, mariners and waterfront facilities at or near this event. C. Discussion of... on the human environment. This rule is categorically excluded, under figure 2-1, paragraph (34)(g...

Anthropic selection and the habitability of planets orbiting M and K dwarfs

NASA Astrophysics Data System (ADS)

Waltham, Dave

2011-10-01

The Earth may have untypical characteristics which were necessary preconditions for the emergence of life and, ultimately, intelligent observers. This paper presents a rigorous procedure for quantifying such "anthropic selection" effects by comparing Earth's properties to those of exoplanets. The hypothesis that there is anthropic selection for stellar mass (i.e. planets orbiting stars with masses within a particular range are more favourable for the emergence of observers) is then tested. The results rule out the expected strong selection for low mass stars which would result, all else being equal, if the typical timescale for the emergence of intelligent observers is very long. This indicates that the habitable zone of small stars may be less hospitable for intelligent life than the habitable zone of solar-mass stars. Additional planetary properties can also be analyzed, using the approach introduced here, once relatively complete and unbiased statistics are made available by current and planned exoplanet characterization projects.

Intra-community implications of implementing multiple tsunami-evacuation zones in Alameda, California

USGS Publications Warehouse

Peters, Jeff; Wood, Nathan J.; Wilson, Rick; Miller, Kevin

2016-01-01

Tsunami-evacuation planning in coastal communities is typically based on maximum evacuation zones for a single scenario or a composite of sources; however, this approach may over-evacuate a community and overly disrupt the local economy and strain emergency-service resources. To minimize the potential for future over-evacuations, multiple evacuation zones based on arrival time and inundation extent are being developed for California coastal communities. We use the coastal city of Alameda, California (USA), as a case study to explore population and evacuation implications associated with multiple tsunami-evacuation zones. We use geospatial analyses to estimate the number and type of people in each tsunami-evacuation zone and anisotropic pedestrian evacuation models to estimate pedestrian travel time out of each zone. Results demonstrate that there are tens of thousands of individuals in tsunami-evacuation zones on the two main islands of Alameda, but they will likely have sufficient time to evacuate before wave arrival. Quality of life could be impacted by the high number of government offices, schools, day-care centers, and medical offices in certain evacuation zones and by potentially high population density at one identified safe area after an evacuation. Multi-jurisdictional evacuation planning may be warranted, given that many at-risk individuals may need to evacuate to neighboring jurisdictions. The use of maximum evacuation zones for local tsunami sources may be warranted given the limited amount of available time to confidently recommend smaller zones which would result in fewer evacuees; however, this approach may also result in over-evacuation and the incorrect perception that successful evacuations are unlikely.

Volcanic hazards on the Island of Hawaii

USGS Publications Warehouse

Mullineaux, Donal Ray; Peterson, Donald W.

1974-01-01

Volcanic hazards on the Island of Hawaii have been determined to be chiefly products of eruptions: lava flows, falling fragments, gases, and particle-and-gas clouds. Falling fragments and particle-and-gas clouds can be substantial hazards to life, but they are relatively rare. Lava flows are the chief hazard to property; they are frequent and cover broad areas. Rupture, subsidence, earthquakes, and sea waves (tsunamis) caused by eruptions are minor hazards; those same events caused by large-scale crustal movements, however, are major hazards to both life and property. Volcanic hazards are greatest on Mauna Loa and Kilauea, and the risk is highest along the rift zones of those volcanoes. The hazards are progressively less severe on Hualalai, Mauna Kea, and Kohala volcanoes. Some risk from earthquakes extends across the entire island, and the risk from tsunamis is high all along the coast. The island has been divided into geographic zones of different relative risk for each volcanic hazard, and for all those hazards combined. Each zone is assigned a relative risk for that area as a whole; the degree of risk varies within the zones, however, and in some of them the risk decreases gradationally across the entire zone. Moreover, the risk in one zone may be locally as great or greater than that at some points in the zone of next higher overall risk. Nevertheless, the zones can be highly useful for land-use planning. Planning decisions to which the report is particularly applicable include the selection of kinds of structures and kinds of land use that are appropriate for the severity and types of hazards present. For example, construction of buildings that can resist a lava flow is generally not feasible, but it is both feasible and desirable to build structures that can resist falling rock fragments, earthquakes, and tsunamis in areas where risk from those hazards is relatively high. The report can also be used to select sites where overall risk is relatively low, to identify sites where either overall risk or risk from some specific hazard is relatively high, and to identify areas in which there is a threat to lives as well as to property. The report further can serve as a basis for warning persons about hazards in areas most likely to be affected by volcanic eruptions. Perhaps most important, however, the report provides basic information needed for zoning to control future land use.

De-repression of the RAC activator ELMO1 in cancer stem cells drives progression of TGFβ-deficient squamous cell carcinoma from transition zones

PubMed Central

McCauley, Heather A; Chevrier, Véronique; Birnbaum, Daniel; Guasch, Géraldine

2017-01-01

Squamous cell carcinomas occurring at transition zones are highly malignant tumors with poor prognosis. The identity of the cell population and the signaling pathways involved in the progression of transition zone squamous cell carcinoma are poorly understood, hence representing limited options for targeted therapies. Here, we identify a highly tumorigenic cancer stem cell population in a mouse model of transitional epithelial carcinoma and uncover a novel mechanism by which loss of TGFβ receptor II (Tgfbr2) mediates invasion and metastasis through de-repression of ELMO1, a RAC-activating guanine exchange factor, specifically in cancer stem cells of transition zone tumors. We identify ELMO1 as a novel target of TGFβ signaling and show that restoration of Tgfbr2 results in a complete block of ELMO1 in vivo. Knocking down Elmo1 impairs metastasis of carcinoma cells to the lung, thereby providing insights into the mechanisms of progression of Tgfbr2-deficient invasive transition zone squamous cell carcinoma. DOI: http://dx.doi.org/10.7554/eLife.22914.001 PMID:28219480

THESIS: terrestrial and habitable zone infrared spectroscopy spacecraft

NASA Astrophysics Data System (ADS)

Vasisht, G.; Swain, M. R.; Akeson, R. L.; Burrows, A.; Deming, D.; Grillmair, C. J.; Greene, T. P.

2008-07-01

THESIS is a concept for a medium class mission designed for spectroscopic characterization of extrasolar planets between 2-14 microns. The concept leverages off the recent first-steps made by Spitzer and Hubble in characterizing the atmospheres of alien gas giants. Under favourable circumstances, THESIS is capable of identifying biogenic molecules in habitable-zone planets, thereby determining conditions on worlds where life might exist. By systematically characterizing many worlds, from rocky planets to gas-giants, THESIS would deliver transformational science of profound interest to astronomers and the general public.

Kepler: NASA's First Mission Capable of Finding Earth-Size Planets

NASA Technical Reports Server (NTRS)

Borucki, William J.

2009-01-01

Kepler, a NASA Discovery mission, is a spaceborne telescope designed to search a nearby region of our galaxy for Earth-size planets orbiting in the habitable zone of stars like our sun. The habitable zone is that region around a start where the temperature permits water to be liquid on the surface of a planet. Liquid water is considered essential forth existence of life. Mission Phases: Six mission phases have been defined to describe the different periods of activity during Kepler's mission. These are: launch; commissioning; early science operations, science operations: and decommissioning

The Effects: Dead Zones and Harmful Algal Blooms

EPA Pesticide Factsheets

Excess nitrogen and phosphorus can cause algae blooms. The overgrowth of algae consumes oxygen and blocks sunlight from underwater plants. When the algae die, the oxygen in the water is consumed, making it impossible for aquatic life to survive.

Silvics of whitebark pine (Pinus albicaulis)

Treesearch

Stephen F. Arno; Raymond J. Hoff

1989-01-01

Whitebark pine (Pinus albicaulis) is a long-lived tree inhabiting the upper subalpine forest and timberline zone on high mountains of Western North America. The species' habitat, life history, growth and yield, mortality factors, special uses, and genetics are described.

Mammea americana L.

Treesearch

Nadia Navarrete-Tindall; Mario A. Orellana N& #250; & #241; ez; & #241; Mario A. Orellana ez

2002-01-01

Mammea americana is native to the West Indies, but is widely cultivated in the tropics in Central America and the Caribbean islands (National Germplasm Repository 1995). It is found in tropical and subtropical life zones in dry and wet forests (Lamberts and Crane 1990).

76 FR 1519 - Security Zones; Sabine Bank Channel, Sabine Pass Channel and Sabine-Neches Waterway, TX

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-11

... comprehensive port security regime designed to safeguard human life, vessels, and waterfront facilities against... do not individually or cumulatively have a significant effect on the human environment. This rule is...

Sailing for stretched lithosphere

NASA Astrophysics Data System (ADS)

2008-07-01

Having managed to get themselves and all their instruments on board a ship not too far away from an imminent war zone, Jenny Collier and colleagues enjoyed the serenity of life at sea as they investigated the rifted continental margin of India.

The photo-biophylic character of the Milky Way

NASA Astrophysics Data System (ADS)

Martín, Osmel; Cárdenas, Rolando; Horvath, Jorge

2011-02-01

It is investigated how biofriendly is the Milky Way for photosynthetic life. Special attention is dedicated to the role of the photobiological regime in the emergence and evolution of this kind of life in terrestrial planets. Following this line, it is investigated the potential role of stellar explosions as a potential environmental perturbation in planets, emphasizing on Earth. The difficulties in modelling the behaviour of stressed biological systems and the robustness of life leads us to conclude the relative arbitrariness of defining a galactic habitable zone with today's limited knowledge on the very possible diverse sets of living creatures.

Personal records from my tattoo parlour: deep emotions drawn as life-long pictures on the skin's canvas.

PubMed

Kierstein, Liz

2015-01-01

The author, who has been a professional tattooist for years, reports four individuals whose tragic life events led to decisions to be tattooed with illustrations of their life stories. The authors' personal experiences with tattooist-client interactions and clients' expectations and demands are reviewed. During the last decade, tattooing has moved in the direction of becoming more individualized and is often very personal. The working process and the intimacy between the client and tattooist create a comfort zone of trust and loyalty. © 2015 S. Karger AG, Basel.

Migration and geographic variations in blood pressure in Britain.

PubMed Central

Elford, J; Phillips, A; Thomson, A G; Shaper, A G

1990-01-01

OBJECTIVE--To evaluate the relative contributions of factors acting at different stages in life to regional differences in adult blood pressure. DESIGN--Prospective cohort study (British regional heart study). SETTING--One general practice in each of 24 towns in Britain. SUBJECTS--7735 Men aged 40-59 years when screened in 1978-80 whose geographic zone of birth and zone of examination were classified as south of England, midlands and Wales, north of England, and Scotland. Non-migrants (n = 3144) were born in the town where they were examined; internal migrants (n = 4147) were born in Great Britain but not in the town where they were examined; and international migrants (n = 422) were born outside Great Britain. MAIN OUTCOME MEASURES--Systolic and diastolic blood pressures and height. RESULTS--Regardless of where they were born, men living in the south of England had lower mean blood pressures than men living in Scotland (142.5/80.1 v 148.1/85.2 mm Hg). The effects of the place of birth and place of examination on adult blood pressure were examined in a multiple regression model. For internal migrants the modelled increase in mean systolic blood pressure across adjacent zones of examination was 2.1 mm Hg (95% confidence interval 1.3 to 2.9); for adjacent zones of birth the corresponding increase was 0.1 mm Hg (-0.7 to 0.7). The place of examination seemed to be a far more important determinant of mean adult blood pressure than the place of birth. Height is an accepted marker of genetic and early life influences. Regional differences in height were therefore analysed to test whether the multiple regression model could correctly distinguish between the influence of place of birth and place of examination. As expected, men born in Scotland were shorter on average than men born in the south of England irrespective of where they lived in Britain (172.6 cm v 175.1 cm for internal migrants). CONCLUSION--Regional variations in blood pressure were strongly influenced by where the men had lived for most of their adult lives rather than by where they were born and brought up. Among middle aged men, factors acting in adult life seemed to be more important determinants of regional differences in blood pressure than those acting early in life such as genetic inheritance, intrauterine environment, and childhood experience. PMID:2106957

Soil processes and functions across an international network of Critical Zone Observatories: Introduction to experimental methods and initial results

NASA Astrophysics Data System (ADS)

Banwart, Steven; Menon, Manoj; Bernasconi, Stefano M.; Bloem, Jaap; Blum, Winfried E. H.; Souza, Danielle Maia de; Davidsdotir, Brynhildur; Duffy, Christopher; Lair, Georg J.; Kram, Pavel; Lamacova, Anna; Lundin, Lars; Nikolaidis, Nikolaos P.; Novak, Martin; Panagos, Panos; Ragnarsdottir, Kristin Vala; Reynolds, Brian; Robinson, David; Rousseva, Svetla; de Ruiter, Peter; van Gaans, Pauline; Weng, Liping; White, Tim; Zhang, Bin

2012-11-01

Growth in human population and demand for wealth creates ever-increasing pressure on global soils, leading to soil losses and degradation worldwide. Critical Zone science studies the impact linkages between these pressures, the resulting environmental state of soils, and potential interventions to protect soil and reverse degradation. New research on soil processes is being driven by the scientific hypothesis that soil processes can be described along a life cycle of soil development. This begins with formation of new soil from parent material, development of the soil profile, and potential loss of the developed soil functions and the soil itself under overly intensive anthropogenic land use, thus closing the cycle. Four Critical Zone Observatories in Europe have been selected focusing research at sites that represent key stages along the hypothetical soil life cycle; incipient soil formation, productive use of soil for farming and forestry, and decline of soil due to longstanding intensive agriculture. Initial results from the research show that soil develops important biogeochemical properties on the time scale of decades and that soil carbon and the development of favourable soil structure takes place over similar time scales. A new mathematical model of soil aggregate formation and degradation predicts that set-aside land at the most degraded site studied can develop substantially improved soil structure with the accumulation of soil carbon over a period of several years. Further results demonstrate the rapid dynamics of soil carbon; how quickly it can be lost, and also demonstrate how data from the CZOs can be used to determine parameter values for models at catchment scale. A structure for a new integrated Critical Zone model is proposed that combines process descriptions of carbon and nutrient flows, a simplified description of the soil food web, and reactive transport; all coupled with a dynamic model for soil structure and soil aggregation. This approach is proposed as a methodology to analyse data along the soil life cycle and test how soil processes and rates vary within, and between, the CZOs representing different life cycle stages. In addition, frameworks are discussed that will help to communicate the results of this science into a more policy relevant format using ecosystem service approaches.

A study of climate change and anthropogenic impacts in West Africa.

PubMed

Wittig, Rüdiger; König, Konstantin; Schmidt, Marco; Szarzynski, Jörg

2007-05-01

During the last decades ecological conditions in West Africa have dramatically changed. Very evident is the climate change, which has resulted in a southward shift of the climate zones, e.g. a spread of the desert (Sahara) into the Sahelian zone. After the drought period of the early 1970s and 1980s, livestock density increased resulting in an intensification of grazing pressure. This anthropogenous phenomenon leads to similar landscape changes as those caused by the climate. Only very few investigations exist on vegetation dynamics, climate changes and land use changes for the Sudanian zone. The paper presents data on changes of precipitation, of land use, of the geographical range of species, and of the composition of the flora, which have to be regarded as proofs of the sahelisation of large areas of the Sudanian zone. Area of investigation: Burkina Faso. Precipitation data analysis: precipitation data from 67 stations; time series analysis and geo-statistical spatial interpolation. Analysis of land use change: Landsat satellite MSS and ETM+ data, acquired for two different dates between 1972 and 2001 analyzed by the software ERDAS/IMAGINE version 8.6 and ArcView 3.2 with the Spatial Analyst extension. Intensive ground truthing (160 training areas). Inventory of the flora: based on the data of the Herbarium Senckenbergianum (FR) in Frankfurt, Germany, and of the herbarium of the university of Ouagadougou (OUA), Burkina Faso, as well as on various investigations on the vegetation of Burkina Faso carried out in the years 1990 to 2005 by the team of the senior author. Life form analysis of the flora: based on the inventory of permanent plots. Precipitation: Remarkable latitudinal shift of isohyets towards the South translates to a general reduction of average rainfall in great parts of the country. The last decade (1990-1999) shows some improvement, however, the more humid conditions of the 1950's and 1960's are not yet established again. Landcover change: In the study region the extent of arable fields and young fallows increased during the last 30 years from 580 km(2) in 1972 to 2870 km(2) in 2001. This means an average land cover conversion rate of 0.9% per year for the 6 departments considered. Change of the distribution of Sahelian and Sudanian species: Several species, mentioned in older literature as strictly Sahelian, today also occur in the Sudanian zone. Parallel to the spread of former strictly Sahelian species into the Sudanian zone, some former Sahelo-Sudanian species have withdrawn from the Sahel. Changes of the life form spectra of the flora: Considering their life form spectra, the flora of heavily grazed and of protected areas in the Sudanian zone show great differences. On areas intensively grazed the percentage of therophytes is evidently higher than on protected areas. Just the opposite is true for the phanerophytes. Their percentage is higher on the protected area than on the grazed zones. At the first glance, it is obvious to link the changes in flora and vegetation with the climate changes that have occurred during the last five decades (decrease of annual precipitation). However, not only climatic conditions have changed, but also population has increased, the percentage of land intensively used for agriculture and pasturing has increased and the time for soil regeneration today is much shorter than it was some decades ago. Thus, the landscape of the Sudanian zone has become a more Sahelian character. A comparison of the flora of an intensively used area of the Sudanian zone with that of a protected area shows a remarkable change in the life form spectra. The spectrum of the intensively used area is almost identical with that of the typical Sahelian flora. This comparison shows that the anthropogenic influence plays a greater role in the sahelisation of the Sudanian zone than the climate change. Climate change and anthropogenic influence both, lead to a sahelisation of landscape and flora. Thus in many parts of the Sudanian zone of West Africa sahelisation phenomena will remain and even increase independently from the reestablishment of the more humid climate conditions of the 1950ies. In order to maintain some parts of the characteristic Sudanian landscape with its characteristic flora and vegetation, the number and size of protected areas should be augmented. For all protected areas it has to be ensured, that protection is reality, i.e. respected an understood by local people, not only fiction. As long as the enlargement of intensively used areas continues the sahelisation of flora, vegetation and landscape will continue too.

Origin and evolution of life on terrestrial planets.

PubMed

Brack, A; Horneck, G; Cockell, C S; Bérces, A; Belisheva, N K; Eiroa, Carlos; Henning, Thomas; Herbst, Tom; Kaltenegger, Lisa; Léger, Alain; Liseau, Réne; Lammer, Helmut; Selsis, Franck; Beichman, Charles; Danchi, William; Fridlund, Malcolm; Lunine, Jonathan; Paresce, Francesco; Penny, Alan; Quirrenbach, Andreas; Röttgering, Huub; Schneider, Jean; Stam, Daphne; Tinetti, Giovanna; White, Glenn J

2010-01-01

The ultimate goal of terrestrial planet-finding missions is not only to discover terrestrial exoplanets inside the habitable zone (HZ) of their host stars but also to address the major question as to whether life may have evolved on a habitable Earth-like exoplanet outside our Solar System. We note that the chemical evolution that finally led to the origin of life on Earth must be studied if we hope to understand the principles of how life might evolve on other terrestrial planets in the Universe. This is not just an anthropocentric point of view: the basic ingredients of terrestrial life, that is, reduced carbon-based molecules and liquid H(2)O, have very specific properties. We discuss the origin of life from the chemical evolution of its precursors to the earliest life-forms and the biological implications of the stellar radiation and energetic particle environments. Likewise, the study of the biological evolution that has generated the various life-forms on Earth provides clues toward the understanding of the interconnectedness of life with its environment.

A comparison of the Landsat image and LAHARZ-simulated lahar inundation hazard zone by the 2010 Merapi eruption

NASA Astrophysics Data System (ADS)

Lee, Seul-Ki; Lee, Chang-Wook; Lee, Saro

2015-06-01

Located above the Java subduction zone, Merapi Volcano is an active stratovolcano with a volcanic activity cycle of 1-5 years. Most Merapi eruptions are relatively small with volcanic explosivity index (VEI) of 1-3. However, the most recent eruption, which occurred in 2010, was quite violent with a VEI of 4 and 386 people were killed. In this study, lahars and pyroclastic flow zones were detected using optical Landsat images and the lahar and pyroclastic flow zone simulated using the LAHARZ program. To detect areal extents of lahar and pyroclastic flows using Landsat images, supervised classification was performed after atmospheric correction by using a cosine of the solar zenith correction (COST) model. As a result, the extracted dimensions of pyroclastic flows are nearly identical to the Calatrava Volcanic Province (CVP) monthly reports. Then, areas of potential lahar and pyroclastic flow inundation based on flow volume using the LAHARZ program were simulated and mapped. Finally, the detected lahars and pyroclastic flow zones were compared with the simulated potential zones using LAHARZ program and verified. Results showed satisfactory similarity (55.63 %) between the detected and simulated zone. The simulated zones using the LAHARZ program can be used as an essential volcanic hazard map for preventing life and property damages for Merapi Volcano and other hazardous volcanic areas. Also, the LAHARZ program can be used to map volcano hazards in other hazardous volcanic areas.

Micro-topography mediates interactions between corals, algae, and herbivorous fishes on coral reefs

NASA Astrophysics Data System (ADS)

Brandl, S. J.; Hoey, A. S.; Bellwood, D. R.

2014-06-01

Processes occurring during the early life stages of corals are important for the replenishment of coral assemblages and the resilience of coral reefs. However, the factors influencing early life stages of corals are not well understood, and the role of micro-topographic complexity for habitat associations of juvenile corals is largely unexplored. This study investigated the microhabitat distribution patterns of early life stages of corals and a potential macroalgal competitor ( Turbinaria ornata) across two reef zones (reef crest and outer reef flat) on Lizard Island, Great Barrier Reef. In both reef zones, both corals and T. ornata were significantly more abundant in concealed microhabitats than in semi-concealed or open microhabitats (GLMM: P < 0.001). The prevalence of juvenile corals and T. ornata within concealed environments suggests that they might be effective refuges from grazing by herbivorous fishes. The density of juvenile corals was positively related, and density of T. ornata negatively related to the abundance of two groups of herbivorous fishes, pairing rabbitfishes, and surgeonfishes in the genus Zebrasoma (BEST ENV-BIO: r s = 0.72, P < 0.01), which feed in concealed microhabitats. This correlative evidence suggests that crevices may be important for early life stages of both coral and macroalgae, and that a specific suite of crevice-feeding fishes may influence benthic community dynamics in these microhabitats.

The battle within: understanding the physiology of war-zone stress exposure.

PubMed

Bruner, Victoria E; Woll, Pamela

2011-01-01

Faced with pervasive loss, life threat, and moral conflict in the field of battle, the human body and brain adapt to extraordinary circumstances in extraordinary ways. These adaptations come at a high price, and many men and women returning from Iraq and Afghanistan are paying that price every day. For the clinician who seeks to help, an understanding of the physiology of war-zone stress and resilience is an essential foundation, both for recovery from post-traumatic stress disorder and other conditions, and for addressing the stigma and shame that keep many service members and veterans from seeking and accepting the help and support they need. This article explores ways in which the body and brain adapt to war-zone stress, resulting challenges, and implications for clinical services and ongoing recovery.

Dynamic model of forest area on flood zone of Padang City, West Sumatra Province-Indonesia

NASA Astrophysics Data System (ADS)

Dewata, Indang; Iswandi, U.

2018-05-01

The flood disaster has caused many harm to human life, and the change of watershed characteristic is one of the factors causing the flood disaster. The increase of deforestation due to the increase of water causes the occurrence of flood disaster in the rainy season. The research objective was to develop a dynamic model of forest on flood hazard zone using powersim 10.1. In model development, there are three scenarios: optimistic, moderate, and pessimistic. The study shows that in Padang there are about 13 percent of high flood hazard zones. Deforestation of 4.5 percent/year is one cause that may increased the flooding intensity in Padang. There will be 14 percent of total forest area when management policy of forest absence in 2050.

78 FR 42692 - Safety Zone; Chicago Harbor, Navy Pier Southeast, Chicago, IL

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-17

... necessary and intended to ensure safety of life on the navigable waters of the United States immediately..., 087[deg]36'09'' W; then back to the point of origin. All vessels must obtain permission from the...

33 CFR 100.917 - The Old Club Cannonade, Harsens Island, MI.

Code of Federal Regulations, 2011 CFR

2011-07-01

... SECURITY REGATTAS AND MARINE PARADES SAFETY OF LIFE ON NAVIGABLE WATERS § 100.917 The Old Club Cannonade... creating a triangle shaped safety zone. (NAD 83). This area is near the southern end of Harsens Island in...

Early history of subplate and interstitial neurons: from Theodor Meynert (1867) to the discovery of the subplate zone (1974)

PubMed Central

Judaš, Miloš; Sedmak, Goran; Pletikos, Mihovil

2010-01-01

In this historical review, we trace the early history of research on the fetal subplate zone, subplate neurons and interstitial neurons in the white matter of the adult nervous system. We arrive at several general conclusions. First, a century of research clearly testifies that interstitial neurons, subplate neurons and the subplate zone were first observed and variously described in the human brain – or, in more general terms, in large brains of gyrencephalic mammals, characterized by an abundant white matter and slow and protracted prenatal and postnatal development. Secondly, the subplate zone cannot be meaningfully defined using a single criterion – be it a specific population of cells, fibres or a specific molecular or genetic marker. The subplate zone is a highly dynamic architectonic compartment and its size and cellular composition do not remain constant during development. Thirdly, it is important to make a clear distinction between the subplate zone and the subplate (and interstitial) neurons. The transient existence of the subplate zone (as a specific architectonic compartment of the fetal telencephalic wall) should not be equated with the putative transient existence of subplate neurons. It is clear that in rodents, and to an even greater extent in humans and monkeys, a significant number of subplate cells survive and remain functional throughout life. PMID:20979585

Extending Galactic Habitable Zone Modeling to Include the Emergence of Intelligent Life.

PubMed

Morrison, Ian S; Gowanlock, Michael G

2015-08-01

Previous studies of the galactic habitable zone have been concerned with identifying those regions of the Galaxy that may favor the emergence of complex life. A planet is deemed habitable if it meets a set of assumed criteria for supporting the emergence of such complex life. In this work, we extend the assessment of habitability to consider the potential for life to further evolve to the point of intelligence--termed the propensity for the emergence of intelligent life, φI. We assume φI is strongly influenced by the time durations available for evolutionary processes to proceed undisturbed by the sterilizing effects of nearby supernovae. The times between supernova events provide windows of opportunity for the evolution of intelligence. We developed a model that allows us to analyze these window times to generate a metric for φI, and we examine here the spatial and temporal variation of this metric. Even under the assumption that long time durations are required between sterilizations to allow for the emergence of intelligence, our model suggests that the inner Galaxy provides the greatest number of opportunities for intelligence to arise. This is due to the substantially higher number density of habitable planets in this region, which outweighs the effects of a higher supernova rate in the region. Our model also shows that φI is increasing with time. Intelligent life emerged at approximately the present time at Earth's galactocentric radius, but a similar level of evolutionary opportunity was available in the inner Galaxy more than 2 Gyr ago. Our findings suggest that the inner Galaxy should logically be a prime target region for searches for extraterrestrial intelligence and that any civilizations that may have emerged there are potentially much older than our own.

Development of the hypothalamus and pituitary in platypus (Ornithorhynchus anatinus) and short-beaked echidna (Tachyglossus aculeatus)

PubMed Central

Ashwell, Ken W S

2012-01-01

The living monotremes (platypus and echidnas) are distinguished by the development of their young in a leathery-shelled egg, a low and variable body temperature and a primitive teat-less mammary gland. Their young are hatched in an immature state and must deal with the external environment, with all its challenges of hypothermia and stress, as well as sourcing nutrients from the maternal mammary gland. The Hill and Hubrecht embryological collections have been used to follow the structural development of the monotreme hypothalamus and its connections with the pituitary gland both in the period leading up to hatching and during the lactational phase of development, and to relate this structural maturation to behavioural development. In the incubation phase, development of the hypothalamus proceeds from closure of the anterior neuropore to formation of the lateral hypothalamic zone and putative medial forebrain bundle. Some medial zone hypothalamic nuclei are emerging at the time of hatching, but these are poorly differentiated and periventricular zone nuclei do not appear until the first week of post-hatching life. Differentiation of the pituitary is also incomplete at hatching, epithelial cords do not develop in the pars anterior until the first week, and the hypothalamo-neurohypophyseal tract does not appear until the second week of post-hatching life. In many respects, the structure of the hypothalamus and pituitary of the newly hatched monotreme is similar to that seen in newborn marsupials, suggesting that both groups rely solely on lateral hypothalamic zone nuclei for whatever homeostatic mechanisms they are capable of at birth/hatching. PMID:22512474

Understanding the South Pacific Convergence Zone and Its Impacts

NASA Astrophysics Data System (ADS)

Power, Scott

2011-02-01

International Workshop on the South Pacific Convergence Zone; Apia, Samoa, 24-26 August 2010 ; During the Southern Hemisphere summer the South Pacific Convergence Zone (SPCZ) in the southwestern Pacific Ocean produces the largest rainfall band in the world. The SPCZ tends to move northeast during southern winter and El Niño and move southwest during southern summer and La Niña. These changes in position have a profound influence on climate (e.g., rainfall, winds, and tropical cyclone frequencies) and life in most of the nations in the southwestern Pacific. Despite the importance of the SPCZ to the region and its prominence in the general circulation of the Southern Hemisphere, the SPCZ has been studied relatively little compared with convergence zones in the Northern Hemisphere. An international workshop on the SPCZ was held in Samoa and brought together 30 experts from Australia, the Cook Islands, Fiji, France, India, New Caledonia, New Zealand, Samoa, the Solomon Islands, Tonga, Tuvalu, the United Kingdom, the United States, and Vanuatu.

Analytical Investigation of the Decrease in the Size of the Habitable Zone Due to a Limited CO2 Outgassing Rate

NASA Astrophysics Data System (ADS)

Abbot, Dorian S.

2016-08-01

The habitable zone concept is important because it focuses the scientific search for extraterrestrial life and aids the planning of future telescopes. Recent work has shown that planets near the outer edge of the habitable zone might not actually be able to stay warm and habitable if CO2 outgassing rates are not large enough to maintain high CO2 partial pressures against removal by silicate weathering. In this paper, I use simple equations for the climate and CO2 budget of a planet in the habitable zone that can capture the qualitative behavior of the system. With these equations I derive an analytical formula for an effective outer edge of the habitable zone, including limitations imposed by the CO2 outgassing rate. I then show that climate cycles between a snowball state and a warm climate are only possible beyond this limit if the weathering rate in the snowball climate is smaller than the CO2 outgassing rate (otherwise stable snowball states result). I derive an analytical solution for the climate cycles including a formula for their period in this limit. This work allows us to explore the qualitative effects of weathering processes on the effective outer edge of the habitable zone, which is important because weathering parameterizations are uncertain.

Analytical Investigation of the Decrease in the Size of the Habitable Zone due to Limited CO2 Outgassing Rate

NASA Astrophysics Data System (ADS)

Abbot, D. S.

2016-12-01

The habitable zone concept is important because it focuses the scientific search for extraterrestrial life and aids the planning of future telescopes. Recent work has shown that planets near the outer edge of the habitable zone might not actually be able to stay warm and habitable if CO2 outgassing rates are not large enough to maintain high CO2 partial pressures against removal by silicate weathering. I use simple equations for the climate and CO2 budget of a planet in the habitable zone that can capture the qualitative behavior of the system. With these equations I derive an analytical formula for an effective outer edge of the habitable zone, including limitations imposed by the CO2 outgassing rate. I then show that climate cycles between a Snowball state and a warm climate are only possible beyond this limit if the weathering rate in the Snowball climate is smaller than the CO2 outgassing rate (otherwise stable Snowball states result). I derive an analytical solution for the climate cycles including a formula for their period in this limit. This work allows us to explore the qualitative effects of weathering processes on the effective outer edge of the habitable zone, which is important because weathering parameterizations are uncertain.

Guidelines for bus transit stops in highway construction work zones.

DOT National Transportation Integrated Search

2014-12-01

Fixed route transit systems provide a valuable transportation service for many of our citizens. As users depend on : bus transit to access to the essentials of life, maintaining transit service is a critical issue. Given the extent of : nationwide bu...

Life in the Twilight Zone: The Persistence of Myth in Art Education.

ERIC Educational Resources Information Center

Pariser, David

1988-01-01

Focuses on the article by Elliot W. Eisner (1971) in which Eisner identified seven myths held by art educators. Considers which myths are still alive today and the reasons that art education seems doomed to always have myths. (GEA)

Habitable Planets with Dynamic System of Global Air-Liquid-Solid Planet and Life

NASA Astrophysics Data System (ADS)

Miura, Y.; Kato, T.

2017-11-01

Habitable zone is dynamic three phase states (air-liquid-solid), which will be obtained in water-planet with volatile exchanges. Water and carbon-bearing grains at older extraterrestrial stones suggest that there are no global ocean water system.

78 FR 59239 - Safety Zone; Chicago Harbor, Navy Pier Southeast, Chicago, IL

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-26

... action is necessary and intended to ensure safety of life on the navigable waters of the United States...'' N, 087[deg]36'24.6'' W; then east back to the point of origin (NAD 83). All vessels must obtain...

78 FR 28523 - Fisheries of the Exclusive Economic Zone Off Alaska; Bering Sea and Aleutian Islands Crab...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-15

... revenues from crab deliveries and processing. Amendment 41 and this final rule promote the safety of human life at sea and mitigate economic harm by allowing participants to receive an exemption from regional...

Does developmental hypothyroidism produce lasting effects on adult neurogenesis?

EPA Science Inventory

The subgranular zone of the dentate gyrus (DO) of the adult hippocampus generates new neurons throughout life. Thyroid hormones (TH) are essential for brain development, but impaired neurogenesis with adult hypothyroidism has also been reported. We investigated the role of milder...

Surf zone fauna of Ecuadorian sandy beaches: Spatial and temporal patterns

NASA Astrophysics Data System (ADS)

Marin Jarrin, J. R.; Vanaverbeke, J.; Fockedey, N.; de Grunauer, M. del P. Cornejo R.; Dominguez-Granda, L.

2017-02-01

Sandy beaches and their surf zones are the most common open shoreline habitat; however, surf zone fauna in the tropics is one of the least studied communities in the world. In the current study, we tested the hypothesis that Ecuadorian surf zone hyperbenthos (invertebrates and vertebrates 1-5 mm in length) and epibenthos (fish and macrocrustaceans > 5 mm in length) vary among beaches and seasons. Therefore, the fauna was described and related to environmental variables. In addition, indicator taxa were identified. The hyperbenthos was divided into holo- and mero-hyperbenthos depending on whether taxa were present during their entire life or only early life stages, respectively. Samples were collected at eight different beaches during the wet, dry and intermediate or transitional season during the low spring tide, from 1999 to 2000, using a hyperbenthic sledge and epibenthic trawl. A total of 447 hyperbenthic and 30 epibenthic taxa were collected, most of which were crustaceans and fish, respectively (52 and 60% of taxa). The mysid, Metamysidopsis sp., was the most abundant member of the hyperbenthos (average ± SD: 14,425 ± 40,039 ind. 100 m- 2, present in 92% of samples collected), and the swimming blue crab, Areneus mexicanus, was the most encountered species among the epibenthos (1 ± 1 ind. 100 m- 2, 97% of samples collected). All faunal groups varied among beaches, while the holo-hyperbenthos and less strongly the epibenthos varied among seasons. Variability in the three faunas among beaches, distance from the continental slope and the Guayas estuarine system, and beach water physical characteristics were all strongly correlated suggesting adjacent habitats can influence surf zone biological communities and water physical characteristics. Seasonal effects were related to changes in water physical characteristics among seasons potentially reflecting changes in oceanic currents. These results suggest that, similarly to other beaches around the world, Ecuadorian surf zone fauna is abundant, diverse, and vary among beaches and, for some faunal groups, among seasons, potentially due to the influence of adjacent habitats and seasonal changes in oceanic currents.

Reassessing the possibility of life on venus: proposal for an astrobiology mission.

PubMed

Schulze-Makuch, Dirk; Irwin, Louis N

2002-01-01

With their similar size, chemical composition, and distance from the Sun, Venus and Earth may have shared a similar early history. Though surface conditions on Venus are now too extreme for life as we know it, it likely had abundant water and favorable conditions for life when the Sun was fainter early in the Solar System. Given the persistence of life under stabilizing selection in static environments, it is possible that life could exist in restricted environmental niches, where it may have retreated after conditions on the surface became untenable. High-pressure subsurface habitats with water in the supercritical liquid state could be a potential refugium, as could be the zone of dense cloud cover where thermoacidophilic life might have retreated. Technology based on the Stardust Mission to collect comet particles could readily be adapted for a pass through the appropriate cloud layer for sample collection and return to Earth.

Reassessing the Possibility of Life on Venus: Proposal for an Astrobiology Mission

NASA Astrophysics Data System (ADS)

Schulze-Makuch, Dirk; Irwin, Louis N.

2002-06-01

With their similar size, chemical composition, and distance from the Sun, Venus and Earth may have shared a similar early history. Though surface conditions on Venus are now too extreme for life as we know it, it likely had abundant water and favorable conditions for life when the Sun was fainter early in the Solar System. Given the persistence of life under stabilizing selection in static environments, it is possible that life could exist in restricted environmental niches, where it may have retreated after conditions on the surface became untenable. High-pressure subsurface habitats with water in the supercritical liquid state could be a potential refugium, as could be the zone of dense cloud cover where thermoacidophilic life might have retreated. Technology based on the Stardust Mission to collect comet particles could readily be adapted for a pass through the appropriate cloud layer for sample collection and return to Earth.

Examining the Effectiveness of Mindfulness Meditation for Chronic Pain Management in Combat Veterans with Traumatic Brain Injury

DTIC Science & Technology

2013-01-01

third had commented on issues related to his work schedule before losing contact with the researchers. Finally, one patient was excluded due to a...M., Keller, S., & Ware, J. E. (2001). Sleep problems, health- related quality of life, work functioning and health care utilization among the...et al., 2006). Military deployment to a war zone may significantly alter health status and quality of life, elevating the risk of long -term physical

Worlds Fantastic, Worlds Familiar

NASA Astrophysics Data System (ADS)

Buratti, Bonnie J.

2017-02-01

Introduction; 1. Mercury: the hottest little place; 2. Venus: an even hotter place; 3. Mars: the abode of life?; 4. Asteroids and comets: sweat the small stuff; 5. Galileo's treasures: worlds of fire and ice; 6. Enceladus: an active iceball in space; 7. Titan: an Earth in deep freeze?; 8. Iapetus and its friends: the weirdest 'planets' in the Solar System; 9. Pluto: the first view of the 'third zone'; 10. Earths above: the search for exoplanets and life in the universe; Epilogue; Glossary; Acknowledgements; Index.

Determination of the Crack Resistance Parameters at Equipment Nozzle Zones Under the Seismic Loads Via Finite Element Method

NASA Astrophysics Data System (ADS)

Kyrychok, Vladyslav; Torop, Vasyl

2018-03-01

The present paper is devoted to the problem of the assessment of probable crack growth at pressure vessel nozzles zone under the cyclic seismic loads. The approaches to creating distributed pipeline systems, connected to equipment are being proposed. The possibility of using in common different finite element program packages for accurate estimation of the strength of bonded pipelines and pressure vessels systems is shown and justified. The authors propose checking the danger of defects in nozzle domain, evaluate the residual life of the system, basing on the developed approach.

Natural Disasters in Southeastern Brazil Associated with the South Atlantic Convergence Zone

NASA Astrophysics Data System (ADS)

Teixeira Nery, Jonas; Malvestio, Leônidas

2017-04-01

This study analyzed rains in southeastern Brazil associated with the South Atlantic Convergence Zone (SACZ), which resulted in several disasters over the study area. The study period was from 1976 to 2010 and data were obtained from the National Water Agency (ANA) and Department of Water and Energy (DAEE) of the state of São Paulo. Outgoing Longwave Radiation (OLR) data were also used to analyze SACZ, which is an important dynamics influencing spring and summer in this region. A close relationship between SACZ intensity and economic and life losses in the study area was observed.

The Supergalactic Habitable Zone

NASA Astrophysics Data System (ADS)

Mason, Paul

2018-01-01

Habitability in the local universe is examined. Constrained by metal abundance and exposure to sterilizing events, life as we know it requires significantly long periods of stable environmental conditions. Planets within galaxies undergoing major mergers, active AGN, starburst episodes, and merging black holes pose serious threats to long-term habitability. Importantly, the development of several layers of protection from high-energy particles such as a thick atmosphere, a strong planetary magnetic field, an astrosphere, and a galactic magnetic field is of great benefit. Factors such as star type and activity, planet type and composition, the location of a planet within its host galaxy, and even the location within a supercluster of galaxies can affect the potential habitability of planets. We discuss the concept of the Supergalactic Habitable Zone introduced by Mason and Biermann in terms of habitability in the local universe and find that galaxies near the center of the Virgo cluster, for example, have a much lower probability for the development of life as we know it as compared to locations in the Milky Way.

Comparing Mid-Century Climate Change Projections at Convective Resolving Scales (2-km) for Life Zones Within Puerto Rico

NASA Astrophysics Data System (ADS)

Bowden, J.; Wootten, A.; Terando, A. J.; Boyles, R.; Misra, V.; Bhardwaj, A.

2016-12-01

Puerto Rico is home to over 3.5 million people and numerous endemic plant and animal species that may be at risk as a result of anthropogenic climate change. This study downscales three CMIP5 Global Circulation Models (GCMs) to a 2-km horizontal resolution using different regional climate models (RCMs) to resolve the island's climate. Here we compare projected climate change from a single GCM, CCSM4, from two RCMs centered on the mid-century, 2041-2060, for a high greenhouse gas emission scenario, RCP8.5. We will discuss similarities and differences in ecologically relevant climate variables, which were selected based on dialogue with experts who have knowledge about potential biological impacts of climate change for current life zones within Puerto Rico. Notable differences appear between the RCMs and include regions with critical ecosystems, such as the El Yunque National Forest in northeast Puerto Rico. This study helps to highlight RCMs structural uncertainty at convective resolving scales.

The effect of Sequoyah Nuclear Plant on dissolved oxygen in Chickamauga Reservoir

DOE Office of Scientific and Technical Information (OSTI.GOV)

Butkus, S.R.; Shiao, M.C.; Yeager, B.L.

1990-09-01

During the summer of 1985, the Tennessee Division of Water Pollution Control and the Tennessee Wildlife Resources Agency measured dissolved oxygen (DO) concentrations downstream from the Sequoyah Nuclear Plant (SQN) discharge mixing zone that were below the state criterion for DO. The Tennessee General Water Quality Criteria'' specifies that DO should be a minimum of 5.0 mg/l measured at a depth of 5 feet for the protection of fish and aquatic life. The Tennessee Valley Authority developed the present study to answer general concerns about reservoir conditions and potential for adverse effects on aquatic biota. Four objectives were defined formore » this study: (1) to better define the extent and duration of the redistribution of DO in the reservoir, (2) to better understand DO dynamics within the mixing zone, (3) to determine whether DO is being lost (or added) as the condenser cooling water passes through the plant, and (4) to evaluate the potential for impact on aquatic life in the reservoir.« less

Development of extraterrestrial intelligence and physical laws

NASA Astrophysics Data System (ADS)

Troitskij, V. S.

This paper considers the restrictions imposed by physical laws on the development of life and intelligence in the form of extraterrestrial civilizations. For this purpose intelligence is defined as the community of intelligent beings, joined by the exchange of mass, energy and information both between themselves and with the external medium. Due to the limitation of the velocity of exchange of information and, in particular, mass and energy exchange, the dimensions of the intelligence cannot exceed some light days, i.e. they are limited by the habitable zone about their star. It is shown that the energy consumption should not exceed the energy output of their star for the sake of preserving the cosmic near-star zone of life from energetic pollution. With the above restrictions of the energy product it takes millions of years to create an omnidirectional beacon-transmitter signals from which would be received by the contemporary antennas in all our Galaxy. It is realistic to create an omnidirectional beacon operating in the range of no more than 100-1000 light years.

Role of the Western Anatolia Shear Zone (WASZ) in Neotectonics Evolution of the Western Anatolia Extended Terrain, Turkey

NASA Astrophysics Data System (ADS)

Cemen, I.; Gogus, O. H.; Hancer, M.

2013-12-01

The Neotectonics period in western Anatolia Extended Terrain, Turkey (WAET) may have initiated in late Oligocene following the Eocene Alpine collision which produced the Izmir-Ankara suture zone. The Western Anatolia Shear Zone (WASZ) bounds the WAET to the east. The shear zone contains mostly normal faults in the vicinity of the Gulf of Gokova. However, its movement is mostly oblique slip from the vicinity of Tavas towards the Lake of Acigol where it makes a northward bend and possibly joins the Eskisehir fault zone to the north of the town of Afyon. The shear zone forms the southern and eastern margins of the Kale-Tavas, Denizli and Acigol basins. The shear zone is similar in its structural/tectonics setting to the Eastern California Shear zone (ECSZ) of the Basins and Ranges of North America Extended terrain which is also composed of many normal to oblique-slip faults and separates two extended terrains with different rates of extension. Western Anatolia experienced many devastating earthquakes within the last 2000 years. Many of the ancient Greek/Roman city states, including Ephesus, Troy, and Hierapolis were destroyed by large historical earthquakes. During the second half of the 20th century, the region experienced two major large earthquake giving normal fault focal mechanism solutions. They are the 1969, M=6.9 Alasehir and the 1970, M=7.1 Gediz earthquakes. These earthquakes had caused substantial damage and loss of life in the region. Therefore, a comprehensive understanding of the kinematics of the Cenozoic extensional tectonics and earthquake potential of the WASZ in the region, is very important, especially since the fault zone is very close to the major towns in eastern part of western Turkey, such as Mugla, Denizli, Sandikli, Dinar and Afyon.

The public health roots of zoning: in search of active living's legal genealogy.

PubMed

Schilling, Joseph; Linton, Leslie S

2005-02-01

Improvements in the built environment and changes in land-use policy are promising approaches to increasing physical activity among a largely sedentary population. Opportunities for walking and cycling as part of daily life are important to increasing physical activity and improving health. Yet, local zoning codes and related land-use regulations have made it difficult to create vibrant, mixed-use neighborhoods with well-connected streets and more compact development-the infrastructure necessary to support healthier rates of walking and cycling for transportation. To better understand the dynamic nature of land-use law and policy, and how policymakers might accomplish zoning reform to encourage more physically active environments, this paper traces the public health roots of zoning through a family tree of land-use legal doctrines. Zoning and public health laws evolved from the same legal ancestors-the common law of public nuisance and the expansion of state police powers, both premised on protection of the public's health. When the U.S. Supreme Court approved zoning in the 1926 case of Ambler Realty v. Village of Euclid, it nominally recognized the health basis of zoning. But it went on to craft a new legal rationale focused more on protection of property rights and residential neighborhoods. Since Euclid, court decisions have given little consideration to the public health roots of zoning. Given an emerging body of research demonstrating the importance of walking-friendly environments and the deference shown by the courts to the passage of zoning laws, the courts are likely to support policymakers as they move to change zoning systems conceived long ago. Legal, historical, and policy rationales support the modernization of zoning and land use policies that allow sensible mixes of land uses. Mixed land uses make walking an attractive alternative to driving and support a more physically active and healthy citizenry.

Where Wolves Kill Moose: The Influence of Prey Life History Dynamics on the Landscape Ecology of Predation

PubMed Central

Montgomery, Robert A.; Vucetich, John A.; Roloff, Gary J.; Bump, Joseph K.; Peterson, Rolf O.

2014-01-01

The landscape ecology of predation is well studied and known to be influenced by habitat heterogeneity. Little attention has been given to how the influence of habitat heterogeneity on the landscape ecology of predation might be modulated by life history dynamics of prey in mammalian systems. We demonstrate how life history dynamics of moose (Alces alces) contribute to landscape patterns in predation by wolves (Canis lupus) in Isle Royale National Park, Lake Superior, USA. We use pattern analysis and kernel density estimates of moose kill sites to demonstrate that moose in senescent condition and moose in prime condition tend to be wolf-killed in different regions of Isle Royale in winter. Predation on senescent moose was clustered in one kill zone in the northeast portion of the island, whereas predation on prime moose was clustered in 13 separate kill zones distributed throughout the full extent of the island. Moreover, the probability of kill occurrence for senescent moose, in comparison to prime moose, increased in high elevation habitat with patches of dense coniferous trees. These differences can be attributed, at least in part, to senescent moose being more vulnerable to predation and making different risk-sensitive habitat decisions than prime moose. Landscape patterns emerging from prey life history dynamics and habitat heterogeneity have been observed in the predation ecology of fish and insects, but this is the first mammalian system for which such observations have been made. PMID:24622241

Atmospheric Habitable Zones in Y Dwarf Atmospheres

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yates, Jack S.; Palmer, Paul I.; Biller, Beth

We use a simple organism lifecycle model to explore the viability of an atmospheric habitable zone (AHZ), with temperatures that could support Earth-centric life, which sits above an environment that does not support life. To illustrate our model, we use a cool Y dwarf atmosphere, such as WISE J085510.83–0714442.5, whose 4.5–5.2 μ m spectrum shows absorption features consistent with water vapor and clouds. We allow organisms to adapt to their atmospheric environment (described by temperature, convection, and gravity) by adopting different growth strategies that maximize their chance of survival and proliferation. We assume a constant upward vertical velocity through themore » AHZ. We found that the organism growth strategy is most sensitive to the magnitude of the atmospheric convection. Stronger convection supports the evolution of more massive organisms. For a purely radiative environment, we find that evolved organisms have a mass that is an order of magnitude smaller than terrestrial microbes, thereby defining a dynamical constraint on the dimensions of life that an AHZ can support. Based on a previously defined statistical approach, we infer that there are of the order of 10{sup 9} cool Y brown dwarfs in the Milky Way, and likely a few tens of these objects are within 10 pc from Earth. Our work also has implications for exploring life in the atmospheres of temperate gas giants. Consideration of the habitable volumes in planetary atmospheres significantly increases the volume of habitable space in the galaxy.« less

Partial root-zone drying and conventional deficit irrigation applied during the whole berry growth maintain yield and berry quality in 'Crimson Seedless' table grapes

NASA Astrophysics Data System (ADS)

Pérez-Pastor, Alejandro; Domingo, Rafael; De la Rosa, Jose M.°; Rosario Conesa Saura, M.°

2016-04-01

To compare the effects of partial root-zone drying and conventional deficit irrigation applied during post-veraison and the whole berry growth on water relations, yield and berry quality, one experiment was conducted in a commercial vineyard of 'Crimson Seedless' table grapes. Five irrigation treatments were imposed: (i) Control (CTL) irrigated to 110% of crop evapotranspiration (ETc), (ii) regulated deficit irrigation (RDI) irrigated at 50% of CTL during the non- critical period of post-verasion, (iii) continuous deficit irrigation (DIc), irrigated at 50% of CTL throughout the whole berry growing season, (iv) partial root-zone drying (PRD), irrigated similar to RDI, but alternating the irrigation applied in the dry side every 10-14 days; and (v) continuous partial root-zone drying (PRDc), irrigated as DIc but alternating the irrigation in the dry side every 10-14 days. RDI and PRD received 24% and 28% less water than CTL, respectively. These reductions were higher in DIc and PRDc (65% and 53%, respectively). Total yield was not affected by any DI strategy. Only significantly lower values were observed in the weight and height's berries in respect to CTL. However, the colour parameters evaluated increased in all DI treatments, being slightly higher in DIc and PRDc compared with RDI and PRD. In addition, total soluble solids (TSS) were significantly higher in DIc, compared to other irrigated counterparts. Our findings showed that the application of water deficit during the whole berry growth through the use of DIc and PRDc, can be considered for irrigation scheduling in 'Crimson Seedless' table grapes. Acknowledgements This work has been funded by the European Union LIFE+ project IRRIMAN (LIFE13 ENV/ES/000539).

Recovery of Mechanical Properties of a 6061-T6 Aluminum Weld by Heat Treatment After Welding

NASA Astrophysics Data System (ADS)

Pérez, Javier Serrano; Ambriz, Ricardo Rafael; López, Francisco Fernando Curiel; Vigueras, David Jaramillo

2016-07-01

The dilution effects in welds of a 6061-T6 (Al-Si-Mg) alloy obtained by the modified indirect electric arc (MIEA), using an ER4043 filler metal (Al-Si), and postweld heat treatment (PWHT) were analyzed. The soft zone (55 to 70 HV0.1) formed by the microstructural transformation in the heat-affected zone (HAZ) was eliminated. The hardness measurements were presented on a traditional microhardness profile and mapping representation. A hardening effect of the fusion zone was observed; the hardness values were above 120 HV0.1 and tended to be uniform. This behavior could be attributed to the chemical composition of the filler metal, the Mg migration from the base to the weld metal, and the reversible process of the PWHT, which promotes precipitation hardening. Improvement for yield (260 MPa) and tensile strength (310 MPa) of the MIEA joints was observed; these values were similar to those obtained for the base metal. However, the presence of porosity in the fusion zone limits the ductility of the joints (4.3 pct). Even though the yield and tensile strengths of the base metal and welded joints were similar, the stress concentration due to porosity in the weld metal generated data dispersion in fatigue life. As a consequence, the high-cycle fatigue life decreases with respect to the base metal. In contrast, when the crack propagates under elastic conditions, the crack-tip singularity is affected by the porosity in the weld metal (stress liberator). This aspect, in conjunction with the hardening effect in joints subjected to PWHT, improves the fatigue crack growth rate when compared to the as-welded condition.

Development of the hypothalamus and pituitary in platypus (Ornithorhynchus anatinus) and short-beaked echidna (Tachyglossus aculeatus).

PubMed

Ashwell, Ken W S

2012-07-01

The living monotremes (platypus and echidnas) are distinguished by the development of their young in a leathery-shelled egg, a low and variable body temperature and a primitive teat-less mammary gland. Their young are hatched in an immature state and must deal with the external environment, with all its challenges of hypothermia and stress, as well as sourcing nutrients from the maternal mammary gland. The Hill and Hubrecht embryological collections have been used to follow the structural development of the monotreme hypothalamus and its connections with the pituitary gland both in the period leading up to hatching and during the lactational phase of development, and to relate this structural maturation to behavioural development. In the incubation phase, development of the hypothalamus proceeds from closure of the anterior neuropore to formation of the lateral hypothalamic zone and putative medial forebrain bundle. Some medial zone hypothalamic nuclei are emerging at the time of hatching, but these are poorly differentiated and periventricular zone nuclei do not appear until the first week of post-hatching life. Differentiation of the pituitary is also incomplete at hatching, epithelial cords do not develop in the pars anterior until the first week, and the hypothalamo-neurohypophyseal tract does not appear until the second week of post-hatching life. In many respects, the structure of the hypothalamus and pituitary of the newly hatched monotreme is similar to that seen in newborn marsupials, suggesting that both groups rely solely on lateral hypothalamic zone nuclei for whatever homeostatic mechanisms they are capable of at birth/hatching. © 2012 The Author. Journal of Anatomy © 2012 Anatomical Society.

PLAN FOR BETTER EDUCATION THROUGH INTEGATION.

ERIC Educational Resources Information Center

New York City Board of Education, Brooklyn, NY.

IN ORDER TO PREPARE PUPILS TO PARTICIPATE FULLY, REGARDLESS OF ENVIRONMENTAL HANDICAP, IN ECONOMIC, SOCIAL, AND POLITICAL LIFE, SCHOOLS SHOULD MAKE IMPROVEMENTS IN THE PROBLEM OF DESEGREGATION. SPECIFIC PLANS UNDERTAKEN BY NEW YORK CITY REQUIRED THE STUDY OF CERTAIN ASPECTS OF EDUCATION--ELEMENTARY SCHOOL COMMUNITY ZONING, JUNIOR HIGH SCHOOL…

40 CFR 146.70 - Information to be evaluated by the Director.

Code of Federal Regulations, 2010 CFR

2010-07-01

... zone. Such data shall include a description of each well's type, construction, date drilled, location... program, well materials specifications and their life expectancy, logging procedures, deviation checks, and a drilling, testing and coring program; and (17) A demonstration pursuant to part 144, subpart F...

33 CFR 337.9 - Identification and use of disposal areas.

Code of Federal Regulations, 2011 CFR

2011-07-01

...) evaluation and environmental assessment or environmental impact statement should also address long-term... ARMY, DEPARTMENT OF DEFENSE PRACTICE AND PROCEDURE § 337.9 Identification and use of disposal areas. (a... life of existing disposal areas. Requests for water quality certification and/or coastal zone...

The Turbulent Life of Phytoplankton

NASA Technical Reports Server (NTRS)

Ghosal, S.; Rogers, M.; Wray, A.

2000-01-01

Phytoplankton is a generic name for photosynthesizing microscopic organisms that inhabit the upper sunlit layer (euphotic zone) of almost all oceans and bodies of freshwater. They are agents for "primary production," the incorporation of carbon from the environment into living organisms, a process that, sustains the aquatic food web. It is estimated that phytoplankton contribute about half of the global primary production, the other half being due to terrestrial plants. By sustaining the aquatic food web and controlling the biogeochemical cycles through primary production, phytoplankton exert a dominant influence on life on earth. Turbulence influences this process in three very important ways. First, essential mineral nutrients are transported from the deeper layers to the euphotic zone through turbulence. Second, turbulence helps to suspend phytoplankton in the euphotic zone since in still water, the phytoplankton, especially the larger species, tend to settle out of the sunlit layers. Third, turbulence transports phytoplankton from the surface to the dark sterile waters, and this is an important mechanism of loss. Thus, stable phytoplankton populations are maintained through a delicate dynamic balance between the processes of turbulence, reproduction, and sinking. The first quantitative model for this was introduced by Riley, Stommel and Bumpus in 1949. This is an attempt to extend their efforts through a combination of analysis and computer simulation in order to better understand the principal qualitative aspects of the physical/biological coupling of this natural system.

On the Biohabitability of M-dwarf Planets

NASA Astrophysics Data System (ADS)

Wandel, A.

2018-04-01

The recent detection of Earth-sized planets in the habitable zone of Proxima Centauri, Trappist-1, and many other nearby M-type stars has led to speculations whether liquid water and life actually exist on these planets. To a large extent, the answer depends on their yet unknown atmospheres, which may, however, be within observational reach in the near future by JWST, ELT, and other planned telescopes. We consider the habitability of planets of M-type stars in the context of their atmospheric properties, heat transport, and irradiation. Instead of the traditional definition of the habitable zone, we define the biohabitable zone, where liquid water and complex organic molecules can survive on at least part of the planetary surface. The atmospheric impact on the temperature is quantified in terms of the heating factor (a combination of greenhouse heating, stellar irradiation, albedo, etc.) and heat redistribution (horizontal energy transport). We investigate the biohabitable domain (where planets can support surface liquid water and organics) in terms of these two factors. Our results suggest that planets orbiting M-type stars may have life-supporting temperatures, at least on part of their surface, for a wide range of atmospheric properties. We apply this analyses to Proxima Cen b and the Trappist-1 system. Finally, we discuss the implications for the search of biosignatures and demonstrate how they may be used to estimate the abundance of photosynthesis and biotic planets.

Life history traits and phenotypic selection among sunflower crop–wild hybrids and their wild counterpart: implications for crop allele introgression

PubMed Central

Kost, Matthew A; Alexander, Helen M; Jason Emry, D; Mercer, Kristin L

2015-01-01

Hybridization produces strong evolutionary forces. In hybrid zones, selection can differentially occur on traits and selection intensities may differ among hybrid generations. Understanding these dynamics in crop–wild hybrid zones can clarify crop-like traits likely to introgress into wild populations and the particular hybrid generations through which introgression proceeds. In a field experiment with four crop–wild hybrid Helianthus annuus (sunflower) cross types, we measured growth and life history traits and performed phenotypic selection analysis on early season traits to ascertain the likelihood, and routes, of crop allele introgression into wild sunflower populations. All cross types overwintered, emerged in the spring, and survived until flowering, indicating no early life history barriers to crop allele introgression. While selection indirectly favored earlier seedling emergence and taller early season seedlings, direct selection only favored greater early season leaf length. Further, there was cross type variation in the intensity of selection operating on leaf length. Thus, introgression of multiple early season crop-like traits, due to direct selection for greater early season leaf length, should not be impeded by any cross type and may proceed at different rates among generations. In sum, alleles underlying early season sunflower crop-like traits are likely to introgress into wild sunflower populations. PMID:26029263

Telemetric Detection of Chronic Obstructive Pulmonary Disease and Investigation of Quality of Life for People Working in Shipbuilding Industry

PubMed Central

Koulouri, Agoritsa; Gourgoulianis, Konstantinos; Hatzoglou, Chryssi; Roupa, Zoe

2014-01-01

ABSTRACT Introduction: Chronic Obstructive Pulmonary Disease (COPD) has a significant impact on quality of life-related health. Aim: It was the detection of Chronic Obstructive Pulmonary Disease by using telemetric methods and the investigation of the quality of life for people working in Shipbuilding Industry compared with a control group. Methods: A group of one hundred men working in the shipbuilding industry aged 51.8 ± 8.2 years old and a control group of one hundred men of the general population aged 51.1 ± 6.4 years were studied. All participants completed the General Health Questionnaire – 28, the Fagerstrom test and a form with demographic characteristics. Pulmonary function test results were electronically sent to a specialist for evaluation. Results: People working in the shipbuilding zone had significantly lower values (p<0.001) in FVC, FEV1 and FEV1/FVC compared with the general population participants. Worse social functionality was exhibited by workers in the shipbuilding zone, people with elementary education, unemployed and by those suffering from comorbidities (p <0.001). Conclusions: Health level and its individual dimensions are both associated with health self-assessment and occupational and economic status. The coexistence of chronic diseases and smoking dependence affects emotion and social functioning of individuals. PMID:25568580

Telemetric detection of chronic obstructive pulmonary disease and investigation of quality of life for people working in shipbuilding industry.

PubMed

Koulouri, Agoritsa; Gourgoulianis, Konstantinos; Hatzoglou, Chryssi; Roupa, Zoe

2014-10-01

Chronic Obstructive Pulmonary Disease (COPD) has a significant impact on quality of life-related health. It was the detection of Chronic Obstructive Pulmonary Disease by using telemetric methods and the investigation of the quality of life for people working in Shipbuilding Industry compared with a control group. A group of one hundred men working in the shipbuilding industry aged 51.8 ± 8.2 years old and a control group of one hundred men of the general population aged 51.1 ± 6.4 years were studied. All participants completed the General Health Questionnaire - 28, the Fagerstrom test and a form with demographic characteristics. Pulmonary function test results were electronically sent to a specialist for evaluation. People working in the shipbuilding zone had significantly lower values (p<0.001) in FVC, FEV1 and FEV1/FVC compared with the general population participants. Worse social functionality was exhibited by workers in the shipbuilding zone, people with elementary education, unemployed and by those suffering from comorbidities (p <0.001). Health level and its individual dimensions are both associated with health self-assessment and occupational and economic status. The coexistence of chronic diseases and smoking dependence affects emotion and social functioning of individuals.

Life history traits and phenotypic selection among sunflower crop-wild hybrids and their wild counterpart: implications for crop allele introgression.

PubMed

Kost, Matthew A; Alexander, Helen M; Jason Emry, D; Mercer, Kristin L

2015-06-01

Hybridization produces strong evolutionary forces. In hybrid zones, selection can differentially occur on traits and selection intensities may differ among hybrid generations. Understanding these dynamics in crop-wild hybrid zones can clarify crop-like traits likely to introgress into wild populations and the particular hybrid generations through which introgression proceeds. In a field experiment with four crop-wild hybrid Helianthus annuus (sunflower) cross types, we measured growth and life history traits and performed phenotypic selection analysis on early season traits to ascertain the likelihood, and routes, of crop allele introgression into wild sunflower populations. All cross types overwintered, emerged in the spring, and survived until flowering, indicating no early life history barriers to crop allele introgression. While selection indirectly favored earlier seedling emergence and taller early season seedlings, direct selection only favored greater early season leaf length. Further, there was cross type variation in the intensity of selection operating on leaf length. Thus, introgression of multiple early season crop-like traits, due to direct selection for greater early season leaf length, should not be impeded by any cross type and may proceed at different rates among generations. In sum, alleles underlying early season sunflower crop-like traits are likely to introgress into wild sunflower populations.

'One physical system': Tansley's ecosystem as Earth's critical zone.

PubMed

Richter, Daniel deB; Billings, Sharon A

2015-05-01

Integrative concepts of the biosphere, ecosystem, biogeocenosis and, recently, Earth's critical zone embrace scientific disciplines that link matter, energy and organisms in a systems-level understanding of our remarkable planet. Here, we assert the congruence of Tansley's (1935) venerable ecosystem concept of 'one physical system' with Earth science's critical zone. Ecosystems and critical zones are congruent across spatial-temporal scales from vegetation-clad weathering profiles and hillslopes, small catchments, landscapes, river basins, continents, to Earth's whole terrestrial surface. What may be less obvious is congruence in the vertical dimension. We use ecosystem metabolism to argue that full accounting of photosynthetically fixed carbon includes respiratory CO₂ and carbonic acid that propagate to the base of the critical zone itself. Although a small fraction of respiration, the downward diffusion of CO₂ helps determine rates of soil formation and, ultimately, ecosystem evolution and resilience. Because life in the upper portions of terrestrial ecosystems significantly affects biogeochemistry throughout weathering profiles, the lower boundaries of most terrestrial ecosystems have been demarcated at depths too shallow to permit a complete understanding of ecosystem structure and function. Opportunities abound to explore connections between upper and lower components of critical-zone ecosystems, between soils and streams in watersheds, and between plant-derived CO₂ and deep microbial communities and mineral weathering. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

Ecological impacts of winter water level drawdowns on lake littoral zones: A review

USGS Publications Warehouse

Roy, Allison

2017-01-01

Freshwater littoral zones harbor diverse ecological communities and serve numerous ecosystem functions that are controlled, in part, by natural water level fluctuations. However, human alteration of lake hydrologic regimes beyond natural fluctuations threaten littoral zone ecological integrity. One type of hydrologic alteration in lakes is winter water level drawdowns, which are frequently employed for hydropower, flood control, and macrophyte control, among other purposes. Here, we synthesize the abiotic and biotic responses to annual and novel winter water level drawdowns in littoral zones of lakes and reservoirs. The dewatering, freezing, and increased erosion of exposed lakebeds drive changes in the littoral zone. Shoreline-specific physicochemical conditions such as littoral slope and shoreline exposure further induce modifications. Loss of fine sediment decreases nutrient availability over time, but desiccation may promote a temporary nutrient pulse upon re-inundation. Annual winter drawdowns can decrease taxonomic richness of macrophytes and benthic invertebrates and shift assemblage composition to favor taxa with r-selected life history strategies and with functional traits resistant to direct and indirect drawdown effects. Fish assemblages, though less directly affected by winter drawdowns (except where there is critically low dissolved oxygen), experience negative effects via indirect pathways like decreased food resources and spawning habitat. We identify eight general research gaps to guide future research that could improve our understanding about the complex effects of winter drawdowns on littoral zone ecology.

Basalt: Biologic Analog Science Associated with Lava Terrains

NASA Astrophysics Data System (ADS)

Lim, D. S. S.; Abercromby, A.; Kobs-Nawotniak, S. E.; Kobayashi, L.; Hughes, S. S.; Chappell, S.; Bramall, N. E.; Deans, M. C.; Heldmann, J. L.; Downs, M.; Cockell, C. S.; Stevens, A. H.; Caldwell, B.; Hoffman, J.; Vadhavk, N.; Marquez, J.; Miller, M.; Squyres, S. W.; Lees, D. S.; Fong, T.; Cohen, T.; Smith, T.; Lee, G.; Frank, J.; Colaprete, A.

2015-12-01

This presentation will provide an overview of the BASALT (Biologic Analog Science Associated with Lava Terrains) program. BASALT research addresses Science, Science Operations, and Technology. Specifically, BASALT is focused on the investigation of terrestrial volcanic terrains and their habitability as analog environments for early and present-day Mars. Our scientific fieldwork is conducted under simulated Mars mission constraints to evaluate strategically selected concepts of operations (ConOps) and capabilities with respect to their anticipated value for the joint human and robotic exploration of Mars. a) Science: The BASALT science program is focused on understanding habitability conditions of early and present-day Mars in two relevant Mars-analog locations (the Southwest Rift Zone (SWRZ) and the East Rift Zone (ERZ) flows on the Big Island of Hawai'i and the eastern Snake River Plain (ESRP) in Idaho) to characterize and compare the physical and geochemical conditions of life in these environments and to learn how to seek, identify, and characterize life and life-related chemistry in basaltic environments representing these two epochs of martian history. b) Science Operations: The BASALT team will conduct real (non-simulated) biological and geological science at two high-fidelity Mars analogs, all within simulated Mars mission conditions (including communication latencies and bandwidth constraints) that are based on current architectural assumptions for Mars exploration missions. We will identify which human-robotic ConOps and supporting capabilities enable science return and discovery. c) Technology: BASALT will incorporate and evaluate technologies in to our field operations that are directly relevant to conducting the scientific investigations regarding life and life-related chemistry in Mars-analogous terrestrial environments. BASALT technologies include the use of mobile science platforms, extravehicular informatics, display technologies, communication & navigation packages, remote sensing, advanced science mission planning tools, and scientifically-relevant instrument packages to achieve the project goals.

Analysis of Chinook Salmon in the Columbia River from an Ecosystem Perspective. Final Report.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lichatowich, James A.; Mobrand, Lars E.

1995-01-01

Ecosystem Diagnosis and Treatment (EDT) methodology was applied to the analysis of chinook salmon in the mid-Columbia subbasins which flow through the steppe and steppe-shrub vegetation zones. The EDT examines historical changes in life history diversity related to changes in habitat. The emphasis on life history, habitat and historical context is consistent with and ecosystem perspective. This study is based on the working hypothesis that the decline in chinook salmon was at least in part due to a loss of biodiversity defined as the intrapopulation life history diversity. The mid Columbia subbasins included in the study are the Deschutes, Johnmore » Day, Umatilla, Tucannon and Yakima.« less

Humanoid Flight Metabolic Simulator Project

NASA Technical Reports Server (NTRS)

Ross, Stuart

2015-01-01

NASA's Evolvable Mars Campaign (EMC) has identified several areas of technology that will require significant improvements in terms of performance, capacity, and efficiency, in order to make a manned mission to Mars possible. These include crew vehicle Environmental Control and Life Support System (ECLSS), EVA suit Portable Life Support System (PLSS) and Information Systems, autonomous environmental monitoring, radiation exposure monitoring and protection, and vehicle thermal control systems (TCS). (MADMACS) in a Suit can be configured to simulate human metabolism, consuming crew resources (oxygen) in the process. In addition to providing support for testing Life Support on unmanned flights, MADMACS will also support testing of suit thermal controls, and monitor radiation exposure, body zone temperatures, moisture, and loads.

Exploring Wildlife, Unit 1, Colorado Division of Wildlife.

ERIC Educational Resources Information Center

Hooper, Jon K.; Smith, Dwight R.

This booklet on wildlife is part of a series to encourage youth to pursue environmental projects. The booklet discusses various aspects of wildlife management such as life zones, pollution, predator control, game stocking, habitat improvement, hunting, legislation, and careers. Key words are defined, and suggested activities are listed. (MR)

Earth-Like Exoplanets: The Science of NASA's Navigator Program

NASA Technical Reports Server (NTRS)

Lawson, Peter R. (Editor); Traub, Wesley A. (Editor)

2006-01-01

This book outlines the exoplanet science content of NASA's Navigator Program, and it identifies the exoplanet research priorities. The goal of Navigator Program missions is to detect and characterize Earth-like planets in the habitable zone of nearby stars and to search for signs of life on those planets.

Life Between the Grains of Sand: An Introductory Activity for Beginning Marine Education Students.

ERIC Educational Resources Information Center

Schlenker, Richard M.

This document presents the outline of a marine biology science unit designed to introduce students to the study and collection of organisms living in the intertidal zone. Details pertaining to the collection of interstitial organisms and a six-item quiz are included. (SL)

Using a National Park for a Field Trip

ERIC Educational Resources Information Center

Baer, Roy K.

1977-01-01

Describes a one-week camping trip to Acadia National Park (Maine) as a non-credit educational experience. Includes activities such as population studies in intertidal zones, wild life sketching, nature list hikes (forest devastation by fire, beaver ponds, glacial ponds and streams), fishing and clamming rips, and student projects. (CS)

Progress Report on the US Critical Zone Observatory Program

NASA Astrophysics Data System (ADS)

Barrera, E. C.

2014-12-01

The Critical Zone Observatory (CZO) program supported by the National Science Foundation originated from the recommendation of the Earth Science community published in the National Research Council report "Basic Research Opportunities in Earth Sciences" (2001) to establish natural laboratories to study processes and systems of the Critical Zone - the surface and near-surface environment sustaining nearly all terrestrial life. After a number of critical zone community workshops to develop a science plan, the CZO program was initiated in 2007 with three sites and has now grown to 10 sites and a National Office, which coordinates research, education and outreach activities of the network. Several of the CZO sites are collocated with sites supported by the US Long Term Ecological Research (LTER) and the Long Term Agricultural Research (LTAR) programs, and the National Ecological Observatory Network (NEON). Future collaboration with additional sites of these networks will add to the potential to answer questions in a more comprehensive manner and in a larger regional scale about the critical zone form and function. At the international level, CZOs have been established in many countries and strong collaborations with the US program have been in place for many years. The next step is the development of a coordinated international program of critical zone research. The success of the CZO network of sites can be measured in transformative results that elucidate properties and processes controlling the critical zone and how the critical zone structure, stores and fluxes respond to climate and land use change. This understanding of the critical zone can be used to enhance resilience and sustainability, and restore ecosystem function. Thus, CZO science can address major societal challenges. The US CZO network is a facility open to research of the critical zone community at large. Scientific data and information about the US program are available at www.criticalzone.org.

On North Pacific circulation and associated marine debris concentration.

PubMed

Howell, Evan A; Bograd, Steven J; Morishige, Carey; Seki, Michael P; Polovina, Jeffrey J

2012-01-01

Marine debris in the oceanic realm is an ecological concern, and many forms of marine debris negatively affect marine life. Previous observations and modeling results suggest that marine debris occurs in greater concentrations within specific regions in the North Pacific Ocean, such as the Subtropical Convergence Zone and eastern and western "Garbage Patches". Here we review the major circulation patterns and oceanographic convergence zones in the North Pacific, and discuss logical mechanisms for regional marine debris concentration, transport, and retention. We also present examples of meso- and large-scale spatial variability in the North Pacific, and discuss their relationship to marine debris concentration. These include mesoscale features such as eddy fields in the Subtropical Frontal Zone and the Kuroshio Extension Recirculation Gyre, and interannual to decadal climate events such as El Niño and the Pacific Decadal Oscillation/North Pacific Gyre Oscillation. Published by Elsevier Ltd.

High-speed X-ray microscopy by use of high-resolution zone plates and synchrotron radiation.

PubMed

Hou, Qiyue; Wang, Zhili; Gao, Kun; Pan, Zhiyun; Wang, Dajiang; Ge, Xin; Zhang, Kai; Hong, Youli; Zhu, Peiping; Wu, Ziyu

2012-09-01

X-ray microscopy based on synchrotron radiation has become a fundamental tool in biology and life sciences to visualize the morphology of a specimen. These studies have particular requirements in terms of radiation damage and the image exposure time, which directly determines the total acquisition speed. To monitor and improve these key parameters, we present a novel X-ray microscopy method using a high-resolution zone plate as the objective and the matching condenser. Numerical simulations based on the scalar wave field theory validate the feasibility of the method and also indicate the performance of X-ray microscopy is optimized most with sub-10-nm-resolution zone plates. The proposed method is compatible with conventional X-ray microscopy techniques, such as computed tomography, and will find wide applications in time-resolved and/or dose-sensitive studies such as living cell imaging.

Nanodevices for generating power from molecules and batteryless sensing

DOEpatents

Wang, Yinmin; Wang, Xianying; Hamza, Alex V.

2017-01-03

A nanoconverter or nanosensor is disclosed capable of directly generating electricity through physisorption interactions with molecules that are dipole containing organic species in a molecule interaction zone. High surface-to-volume ratio semiconductor nanowires or nanotubes (such as ZnO, silicon, carbon, etc.) are grown either aligned or randomly-aligned on a substrate. Epoxy or other nonconductive polymers are used to seal portions of the nanowires or nanotubes to create molecule noninteraction zones. By correlating certain molecule species to voltages generated, a nanosensor may quickly identify which species is detected. Nanoconverters in a series parallel arrangement may be constructed in planar, stacked, or rolled arrays to supply power to nano- and micro-devices without use of external batteries. In some cases breath, from human or other life forms, contain sufficient molecules to power a nanoconverter. A membrane permeable to certain molecules around the molecule interaction zone increases specific molecule nanosensor selectivity response.

Nanodevices for generating power from molecules and batteryless sensing

DOEpatents

Wang, Yinmin; Wang, Xianying; Hamza, Alex V.

2015-06-09

A nanoconverter or nanosensor is disclosed capable of directly generating electricity through physisorption interactions with molecules that are dipole containing organic species in a molecule interaction zone. High surface-to-volume ratio semiconductor nanowires or nanotubes (such as ZnO, silicon, carbon, etc.) are grown either aligned or randomly-aligned on a substrate. Epoxy or other nonconductive polymers are used to seal portions of the nanowires or nanotubes to create molecule noninteraction zones. By correlating certain molecule species to voltages generated, a nanosensor may quickly identify which species is detected. Nanoconverters in a series parallel arrangement may be constructed in planar, stacked, or rolled arrays to supply power to nano- and micro-devices without use of external batteries. In some cases breath, from human or other life forms, contain sufficient molecules to power a nanoconverter. A membrane permeable to certain molecules around the molecule interaction zone increases specific molecule nanosensor selectivity response.

Exoplanets, extremophiles and habitability

NASA Astrophysics Data System (ADS)

Janot Pacheco, E.; Bernardes, L.

2012-09-01

Estimates of the average surface temperature and CO2 partial atmospheric pressure of already discovered exoplanets supposed to be in their Habitable Zone of their stars were surveyed from the Exoplanet Encyclopedia database. Moreover, since planetary surface temperature strongly depends on its albedo and geodynamic conditions, we have been feeding exoplanetary data into a comprehensive model of Earth's atmosphere to get better estimations. We also investigated the possible presence of "exomoons" belonging to giant planets capable of harbour dynamic stability and to retain atmospheric layers and keep geodynamic activity for long time spans. Collected information on biological data of micro-organisms classified as "extremophiles" indicate that such kind of microbial species could dwell in many of them. We thus propose an extension of the more astronomically defined "Habitable Zone" concept into the more astrobiologically "Extremophile Zone", taking into account other refined parameters allowing survival of more robust life forms.

Nanodevices for generating power from molecules and batteryless sensing

DOEpatents

Wang, Yinmin; Wang, Xianying; Hamza, Alex V.

2014-07-15

A nanoconverter or nanosensor is disclosed capable of directly generating electricity through physisorption interactions with molecules that are dipole containing organic species in a molecule interaction zone. High surface-to-volume ratio semiconductor nanowires or nanotubes (such as ZnO, silicon, carbon, etc.) are grown either aligned or randomly-aligned on a substrate. Epoxy or other nonconductive polymers are used to seal portions of the nanowires or nanotubes to create molecule noninteraction zones. By correlating certain molecule species to voltages generated, a nanosensor may quickly identify which species is detected. Nanoconverters in a series parallel arrangement may be constructed in planar, stacked, or rolled arrays to supply power to nano- and micro-devices without use of external batteries. In some cases breath, from human or other life forms, contain sufficient molecules to power a nanoconverter. A membrane permeable to certain molecules around the molecule interaction zone increases specific molecule nanosensor selectivity response.

The development of fire evaluation system for detention and correctional occupancies

NASA Astrophysics Data System (ADS)

Nelson, H. E.; Shibe, A. J.

1984-12-01

A fire safety evaluation system for detention and correctional occupancies was developed. It can be used for determining if a facility has fire safety equivalent to that obtained by meeting the requirement of a given code. The system was calibrated for use with proposed chapters for detention and correctional occupancies of the Life Safety Code (1985). There are separate sets of requirements for each of four use conditions: one for zoned egress, one for zoned impeded egress, one for impeded egress, and one for contained. Within each set, there are two levels of evaluation: one for partially sprinklered and nonsprinklered buildings, and one for totally sprinklered buildings.

Bernoulli, Darwin, and Sagan: the probability of life on other planets

NASA Astrophysics Data System (ADS)

Rossmo, D. Kim

2017-04-01

The recent discovery that billions of planets in the Milky Way Galaxy may be in circumstellar habitable zones has renewed speculation over the possibility of extraterrestrial life. The Drake equation is a probabilistic framework for estimating the number of technological advanced civilizations in our Galaxy; however, many of the equation's component probabilities are either unknown or have large error intervals. In this paper, a different method of examining this question is explored, one that replaces the various Drake factors with the single estimate for the probability of life existing on Earth. This relationship can be described by the binomial distribution if the presence of life on a given number of planets is equated to successes in a Bernoulli trial. The question of exoplanet life may then be reformulated as follows - given the probability of one or more independent successes for a given number of trials, what is the probability of two or more successes? Some of the implications of this approach for finding life on exoplanets are discussed.

New insights into the development and differentiation of the human anorectal epithelia. Are there clinical consequences?

PubMed Central

Zehm, Sarah; Illig, Romana; Moser, Patrizia; Aigner, Felix

2010-01-01

Purpose The epithelial lining of the anorectum still raises discussions concerning the levels of transition between the various zones and leads to an incomplete understanding of the immmunoprofile of rectal carcinoma. Since the expression of cytokeratins depends on the epithelial cell-type and the parahox-gene CDX2 is important for the development of the colorectal epithelium, we investigated different cytokeratins and CDX2 in the anorectum of human prenatal stages and in adult normal and neoplastic anorecta. Materials and Methods The differentiation and spatiotemporal distribution of the epithelial zones were examined in 33 human embryos and fetuses, in a 2-year-old child and four adults. In comparison, 17 specimens of ultralow rectal adenocarcinoma and 4 specimens of anal carcinoma were investigated. Monoclonal antibodies were directed against cytokeratin (CK) 18, 20, 7 and 14 and CDX2. Results Due to the cytokeratin profile and to CDX2 expression, the different anorectal zones could already be differentiated in human prenatal life. We showed that anorectal epithelial differentiation including the squamous epithelia ran in a craniocaudal direction, and that the anorectal zone was a transitional zone between rectal zone and anal transitional zone where CK 7, 18, 20 and CDX2 are simultaneously expressed. All cases of rectal adenocarcinoma showed positivity for CK 18, 20 and CDX2, and three also labelled for CK 7, whereas CK 14 was only expressed in the cases of anal carcinoma. Conclusions Our results elucidate the connection between the prenatal pattern and the origin of the different types of anorectal carcinoma. PMID:20563874

New insights into the development and differentiation of the human anorectal epithelia. Are there clinical consequences?

PubMed

Fritsch, Helga; Zehm, Sarah; Illig, Romana; Moser, Patrizia; Aigner, Felix

2010-10-01

The epithelial lining of the anorectum still raises discussions concerning the levels of transition between the various zones and leads to an incomplete understanding of the immmunoprofile of rectal carcinoma. Since the expression of cytokeratins depends on the epithelial cell-type and the parahox-gene CDX2 is important for the development of the colorectal epithelium, we investigated different cytokeratins and CDX2 in the anorectum of human prenatal stages and in adult normal and neoplastic anorecta. The differentiation and spatiotemporal distribution of the epithelial zones were examined in 33 human embryos and fetuses, in a 2-year-old child and four adults. In comparison, 17 specimens of ultralow rectal adenocarcinoma and 4 specimens of anal carcinoma were investigated. Monoclonal antibodies were directed against cytokeratin (CK) 18, 20, 7 and 14 and CDX2. Due to the cytokeratin profile and to CDX2 expression, the different anorectal zones could already be differentiated in human prenatal life. We showed that anorectal epithelial differentiation including the squamous epithelia ran in a craniocaudal direction, and that the anorectal zone was a transitional zone between rectal zone and anal transitional zone where CK 7, 18, 20 and CDX2 are simultaneously expressed. All cases of rectal adenocarcinoma showed positivity for CK 18, 20 and CDX2, and three also labelled for CK 7, whereas CK 14 was only expressed in the cases of anal carcinoma. Our results elucidate the connection between the prenatal pattern and the origin of the different types of anorectal carcinoma.

`Dhara': An Open Framework for Critical Zone Modeling

NASA Astrophysics Data System (ADS)

Le, P. V.; Kumar, P.

2016-12-01

Processes in the Critical Zone, which sustain terrestrial life, are tightly coupled across hydrological, physical, biological, chemical, pedological, geomorphological and ecological domains over both short and long timescales. Observations and quantification of the Earth's surface across these domains using emerging high resolution measurement technologies such as light detection and ranging (lidar) and hyperspectral remote sensing are enabling us to characterize fine scale landscape attributes over large spatial areas. This presents a unique opportunity to develop novel approaches to model the Critical Zone that can capture fine scale intricate dependencies across the different processes in 3D. The development of interdisciplinary tools that transcend individual disciplines and capture new levels of complexity and emergent properties is at the core of Critical Zone science. Here we introduce an open framework for high-performance computing model (`Dhara') for modeling complex processes in the Critical Zone. The framework is designed to be modular in structure with the aim to create uniform and efficient tools to facilitate and leverage process modeling. It also provides flexibility to maintain, collaborate, and co-develop additional components by the scientific community. We show the essential framework that simulates ecohydrologic dynamics, and surface - sub-surface coupling in 3D using hybrid parallel CPU-GPU. We demonstrate that the open framework in Dhara is feasible for detailed, multi-processes, and large-scale modeling of the Critical Zone, which opens up exciting possibilities. We will also present outcomes from a Modeling Summer Institute led by Intensively Managed Critical Zone Observatory (IMLCZO) with representation from several CZOs and international representatives.

Fatigue Resistance of the Grain Size Transition Zone in a Dual Microstructure Superalloy Disk

NASA Technical Reports Server (NTRS)

Gabb, T. P.; Kantzos, P. T.; Telesman, J.; Gayda, J.; Sudbrack, C. K.; Palsa, B. S.

2010-01-01

Mechanical property requirements vary with location in nickel-based superalloy disks. To maximize the associated mechanical properties, heat treatment methods have been developed for producing tailored microstructures. In this study, a specialized heat treatment method was applied to produce varying grain microstructures from the bore to the rim portions of a powder metallurgy processed nickel-based superalloy disk. The bore of the contoured disk consisted of fine grains to maximize strength and fatigue resistance at lower temperatures. The rim microstructure of the disk consisted of coarse grains for maximum resistance to creep and dwell crack growth at high temperatures up to 704 C. However, the fatigue resistance of the grain size transition zone was unclear, and needed to be evaluated. This zone was located as a band in the disk web between the bore and rim. Specimens were extracted parallel and transverse to the transition zone, and multiple fatigue tests were performed at 427 and 704 C. Mean fatigue lives were lower at 427 C than for 704 C. Specimen failures often initiated at relatively large grains, which failed on crystallographic facets. Grain size distributions were characterized in the specimens, and related to the grains initiating failures as well as location within the transition zone. Fatigue life decreased with increasing maximum grain size. Correspondingly, mean fatigue resistance of the transition zone was slightly higher than that of the rim, but lower than that of the bore. The scatter in limited tests of replicates was comparable for all transition zone locations examined.

Groundwater age, life expectancy and transit time distributions in advective dispersive systems; 2. Reservoir theory for sub-drainage basins

NASA Astrophysics Data System (ADS)

Cornaton, F.; Perrochet, P.

2006-09-01

Groundwater age and life expectancy probability density functions (pdf) have been defined, and solved in a general three-dimensional context by means of forward and backward advection-dispersion equations [Cornaton F, Perrochet P. Groundwater age, life expectancy and transit time distributions in advective-dispersive systems; 1. Generalized reservoir theory. Adv Water Res (xxxx)]. The discharge and recharge zones transit time pdfs were then derived by applying the reservoir theory (RT) to the global system, thus considering as ensemble the union of all inlet boundaries on one hand, and the union of all outlet boundaries on the other hand. The main advantages in using the RT to calculate the transit time pdf is that the outlet boundary geometry does not represent a computational limiting factor (e.g. outlets of small sizes), since the methodology is based on the integration over the entire domain of each age, or life expectancy, occurrence. In the present paper, we extend the applicability of the RT to sub-drainage basins of groundwater reservoirs by treating the reservoir flow systems as compartments which transfer the water fluxes to a particular discharge zone, and inside which mixing and dispersion processes can take place. Drainage basins are defined by the field of probability of exit at outlet. In this way, we make the RT applicable to each sub-drainage system of an aquifer of arbitrary complexity and configuration. The case of the well-head protection problem is taken as illustrative example, and sensitivity analysis of the effect of pore velocity variations on the simulated ages is carried out.

Children's Playgrounds and Everyday City Life of Childhood

ERIC Educational Resources Information Center

Filipova, Alexandra Gennadyevna; Syroed, Nadezhda Savvovna; Goncharova, Svetlana Vladimirovna

2016-01-01

Play areas of entertainment and development are new recourses for modern city children, but at the same time, they produce risks of road traffic accidents, deviation, social inequality and social exclusion. Playgrounds in city/town yards are free zones of children's pastime, where children communicate and play together. The aim of this article is…

A resolution recognizing the life and work of war correspondent Marie Colvin and other courageous journalists in war zones.

THOMAS, 112th Congress

Sen. Whitehouse, Sheldon [D-RI

2012-03-22

Senate - 03/22/2012 Submitted in the Senate, considered, and agreed to without amendment and with a preamble by Unanimous Consent. (All Actions) Tracker: This bill has the status Agreed to in SenateHere are the steps for Status of Legislation:

78 FR 16177 - Safety Zone; M/V XIANG YUN KOU and MODU NOBLE DISCOVERER; Resurrection Bay, Seward, AK

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-14

... and comment. Immediate action is needed to protect human life, property, and the environment from... regulations to the Small Business and Agriculture Regulatory Enforcement Ombudsman and the Regional Small... voluntary consensus standards. 14. Environment We have analyzed this rule under Department of Homeland...

Dry creek long-term watershed study: buffer zone performance as viable amphibian habitat

Treesearch

Brooke L. Talley; Thomas L. Crisman

2006-01-01

As bioindicators, amphibians typically require both terrestrial and aquatic habitats to complete their life cycles. Pre- timber-harvest monitoring (December 2002 through September 2003) of salamander and frog (Hylidae) populations was conducted in four watersheds of Decatur County, GA. Post- timber-harvest monitoring (December 2003 through September...

Life in the Hive: Supporting Inquiry into Complexity within the Zone of Proximal Development

ERIC Educational Resources Information Center

Danish, Joshua A.; Peppler, Kylie; Phelps, David; Washington, DiAnna

2011-01-01

Research into students' understanding of complex systems typically ignores young children because of misinterpretations of young children's competencies. Furthermore, studies that do recognize young children's competencies tend to focus on what children can do in isolation. As an alternative, we propose an approach to designing for young children…

Portable Life Support System: PLSS 101

NASA Technical Reports Server (NTRS)

Thomas, Gretchen A.

2011-01-01

This presentation reviewed basic interfaces and considerations necessary for prototype suit hardware integration from an advanced spacesuit engineer perspective during the early design and test phases. The discussion included such topics such as the human interface, suit pass-throughs, keep-out zones, hardware form factors, subjective feedback from suit tests, and electricity in the suit.

Hyporheic exchange along a river below a dam

Treesearch

Alessandra Marzadri; Daniele Tonina; James A. McKean; Matt Tiedemann

2012-01-01

Hyporheic exchange is an important mechanism for solute mixing between river waters and shallow groundwater in streambed sediment. The hyporheic zone also provides an important ecotone for benthic species, including macro-invertebrates, microorganisms, and parts of some fish life stages. Most hyporheic analyses are limited in scope and performed at the reach scale....

Community Amenity Measurement for the Great Fly-Over Zones

ERIC Educational Resources Information Center

Besser, Terry L.; Miller, Nancy J.; Malik, Roshan

2012-01-01

The purpose of this paper is to provide an alternative operationalization of amenities that does not privilege certain kinds of natural resources and climatic conditions and that can be used for assessing the quality of life in small towns. The amenity inventory presented here extends previous literature by including a broad range of amenities…

Vulnerable Medicine

ERIC Educational Resources Information Center

Bochner, Arthur P.

2009-01-01

In "Narrative Medicine: Honoring the Stories of Illness," Rita Charon paints an original and humane portrait of what it can mean to be a doctor, to live a life immersed in sickness and dedicated to wellness. Charon drops the veil, inviting readers to look at the secret, subjective, emotional face of medicine, a zone of self-censored feelings and…

Recruitment dynamics in complex life cycles. [of organisms living in marine rocky zone

NASA Technical Reports Server (NTRS)

Roughgarden, Jonathan; Possingham, Hugh; Gaines, Steven

1988-01-01

Factors affecting marine population fluctuations are discussed with particular attention given to a common barnacle species of the Pacific coast of North America. It is shown how models combining larval circulation with adult interactions can potentially forecast population fluctuations. These findings demonstrate how processes in different ecological habitats are coupled.

75 FR 69371 - Safety Zone; Beaufort River/Atlantic Intracoastal Waterway, Beaufort, SC

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-12

... is necessary to protect life and property on the navigable waters of the Beaufort River during the... Management Facility (M-30), U.S. Department of Transportation, West Building Ground Floor, Room W12-140, 1200...-0995'' in the ``Keyword'' box. Click ``Search'' then click on the balloon shape in the ``Actions...

Using Sensor-based Demand Controlled Ventilation to Realize Energy Savings in Laboratories

DTIC Science & Technology

2014-03-27

is warranted. The results show that a DCV system is life-cycle cost effective for many different HVAC system total pressure and square footage ...Name and Description of System Sensors ......................................................... 44 Table 5. BEL Laboratory HVAC Zones, Square Footage ...Intensity ............................................................................. 74 Table 9. Range of USAF Laboratory Square Footage and Occupancy

Transcending the Zone of Learning Disability: Learning in Contexts for Everyday Life

ERIC Educational Resources Information Center

Mendez, Laura; Lacasa, Pilar; Matusov, Eugene

2008-01-01

The purpose of this paper is to illustrate a sociocultural approach to studying disability in educational contexts grounded in the cultural-historical and activity theory approaches. From the sociocultural viewpoint, disability is regarded as being located in particular types of activity systems and learning cultures rather than within an…

75 FR 37720 - Safety Zone; New Bern Air Show, Neuse River, NC

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-30

... would be contrary to public interest, since immediate action is needed to ensure the safety of human life and property from the hazards associated with air show operations. Basis and Purpose Coast Guard... effect on the human environment. This rule is categorically excluded, under figure 2-1, paragraph (34)(g...

78 FR 39604 - Safety Zone; Northside Park Pier Fireworks Display, Assawoman Bay, Ocean City, MD

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-02

... Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a temporary safety... protect the life and property of the maritime public and spectators from the hazards associated with...: If you have questions on this temporary rule, call or email LCDR Hector Cintron, Waterways Management...

DEVELOPING AN INTEGRATED ASSESSMENT OF HYPOXIA IN THE NORTHERN GULF OF MEXICO

EPA Science Inventory

Hypoxia is the condition in which dissolved oxygen levels are below that necessary to sustain most animal life. The largest zone of oxygen depletion in the US coastal waters is found in the northern Gulf of Mexico (NGOM) on the LA/TX continental shelf. In response to growing publ...

Quality as Critique: Promoting Critical Reflection among Youth in Structured Encounter Programs

ERIC Educational Resources Information Center

Ross, Karen

2015-01-01

In this manuscript, I interrogate the concept of "quality" encounter programs for youth in conflict zones. I focus on two Israeli organizations implementing encounters for Jewish and Palestinian citizens, and draw upon narratives of former participants as articulated during life history narratives to illustrate divergent emphases in each…

Media Environment as a Zone of Personal and Social Risk

ERIC Educational Resources Information Center

Medvedeva, Tatyana; Kazantseva, Galina; Karpukova, Albina; Serova, Olga; Sizova, Olga; Bikteeva, Lolita

2016-01-01

The paper considers elements of modern media environment taking more and more space in day-to-day life of people. The modern media environment enriched with various informational and technological resources, information transfer speed and availability of all kinds of content in unlimited quantities, requires careful examination--first of all,…

Life extension and the position of the hormetic zone depends on sex and genetic background in Drosophila melanogaster.

PubMed

Sarup, Pernille; Loeschcke, Volker

2011-04-01

Hormesis, the beneficial effect of a mild stress, has been proposed as a means to prolong the period of healthy ageing as it can increase the average lifespan of a cohort. However, if we want to use hormesis therapeutically it is important that the treatment is beneficial on the individual level and not just on average at the population level. Long lived lines have been shown not to benefit from a, in other lines, hormesis inducing heat treatment in Drosophila melanogaster, D. buzzatii and mice. Also in many experiments hormesis has been reported to occur in one sex only, usually males but not in females. Here we investigated the interaction between the hormetic response and genetic background, sex and duration of a mild heat stress in D. melanogaster, using three replicate lines that have been selected for increased longevity and their respective control lines. We found that genetic background influences the position of the hormetic zone. The implication of this result could be that in a genetically diverse populations a treatment that is life prolonging in one individual could be life shortening in other individuals. However, we did find a hormetic response in all combinations of line and sex in at least one of the experiments which suggests that if it is possible to identify the optimal hormetic dose individually hormesis might become a therapeutic treatment.

Water in the critical zone: soil, water and life from profile to planet

NASA Astrophysics Data System (ADS)

Kirkby, Mike

2015-04-01

Water is essential to the critical zone between bedrock and the atmosphere, and without water the soil is dead. Water provides the basis for the abundant life within the soil and, interacting with micro-organisms, drives the key processes in the critical zone. This review looks at the balances that control the flow of water through the soil, and how water movement is one of the major controls on the fluxes and transformations that control the formation, evolution and loss of material that controls the 'life' and 'health' of the soil. At regional scales, climate, acting largely through the soil hydrology, plays a major part in determining the type of soils developed - from hyper arid soils dominated by aeolian inputs, through arid and semi-arid soils with largely vertical water exchanges with the atmosphere, to temperate soils with substantial lateral drainage, and humid soils dominated by organic peats. Soil water balance controls the partition of precipitation between evaporative loss, lateral subsurface flow and groundwater recharge, and, in turn, has a major influence on the potential for plant growth and on the lateral connectivity between soils on a hillslope. Sediment and solute balances distinguish soils of accumulation from soils that tend towards a stable chemical depletion ratio. Reflecting the availability of water and the soil material, carbon balance plays a major role in soil horizonation and distinguishes soils dominated by mineral or organic components. At finer catena and catchment scales, lateral connectivity, or its absence, determines how soils evolve through the transfer of water and sediment downslope, creating more or less integrated landscapes in a balance between geomorphological and pedological processes. Within single soil profiles, the movement of water controls the processes of weathering and soil horizonation by ion diffusion, advective leaching and bioturbation, creating horizonation that, in turn, modifies the hydrological responses of both soil and landscape. For example, the soil hydrological regime helps to contrast soils that accumulate more and less soluble constituents of the parent material.

Kinetic bottlenecks to chemical exchange rates for deep-sea animals - Part 1: Oxygen

NASA Astrophysics Data System (ADS)

Hofmann, A. F.; Peltzer, E. T.; Brewer, P. G.

2012-10-01

Ocean warming will reduce dissolved oxygen concentrations which can pose challenges to marine life. Oxygen limits are traditionally reported simply as a static concentration thresholds with no temperature, pressure or flow rate dependency. Here we treat the oceanic oxygen supply potential for heterotrophic consumption as a dynamic molecular exchange problem analogous to familiar gas exchange processes at the sea surface. A combination of the purely physico-chemical oceanic properties temperature, hydrostatic pressure, and oxygen concentration defines the ability of the ocean to supply oxygen to any given animal. This general oceanic oxygen supply potential is modulated by animal specific properties such as the diffusive boundary layer thickness to define and limit maximal oxygen supply rates. Here we combine all these properties into formal, mechanistic equations defining novel oceanic properties that subsume various relevant classical oceanographic parameters to better visualize, map, comprehend, and predict the impact of ocean deoxygenation on aerobic life. By explicitly including temperature and hydrostatic pressure into our quantities, various ocean regions ranging from the cold deep-sea to warm, coastal seas can be compared. We define purely physico-chemical quantities to describe the oceanic oxygen supply potential, but also quantities that contain organism-specific properties which in a most generalized way describe general concepts and dependencies. We apply these novel quantities to example oceanic profiles around the world and find that temperature and pressure dependencies of diffusion and partial pressure create zones of greatest physical constriction on oxygen supply typically at around 1000 m depth, which coincides with oxygen concentration minimum zones. In these zones, which comprise the bulk of the world ocean, ocean warming and deoxygenation have a clear negative effect for aerobic life. In some shallow and warm waters the enhanced diffusion and higher partial pressure due to higher temperatures might slightly overcompensate for oxygen concentration decreases due to decreases in solubility.

Hymen Restoration: "My" Discomfort, "Their" Culture, and Women's Missing Voice.

PubMed

Schuster, Sylvie

2015-01-01

The discourse among medical and scientific communities on hymen restoration is largely missing the voice of women affected. This article calls for a more nuanced reflection on women's real life experiences and the complexities inherent in the negotiation process about the surgery going beyond "ideologies" and the extremes of rape and threats to life. By taking the clinical experience of a woman who requests restoration surgery before her arranged marriage, this article illuminates the grey zone beyond these extremes and explores an individual woman's options for making her own choices. Copyright 2015 The Journal of Clinical Ethics. All rights reserved.

Constraints on a potential aerial biosphere on Venus: I. Cosmic rays

NASA Astrophysics Data System (ADS)

Dartnell, Lewis R.; Nordheim, Tom Andre; Patel, Manish R.; Mason, Jonathon P.; Coates, Andrew J.; Jones, Geraint H.

2015-09-01

While the present-day surface of Venus is certainly incompatible with terrestrial biology, the planet may have possessed oceans in the past and provided conditions suitable for the origin of life. Venusian life may persist today high in the atmosphere where the temperature and pH regime is tolerable to terrestrial extremophile microbes: an aerial habitable zone. Here we argue that on the basis of the combined biological hazard of high temperature and high acidity this habitable zone lies between 51 km (65 °C) and 62 km (-20 °C) altitude. Compared to Earth, this potential venusian biosphere may be exposed to substantially more comic ionising radiation: Venus has no protective magnetic field, orbits closer to the Sun, and the entire habitable region lies high in the atmosphere - if this narrow band is sterilised there is no reservoir of deeper life that can recolonise afterwards. Here we model the propagation of particle radiation through the venusian atmosphere, considering both the background flux of high-energy galactic cosmic rays and the transient but exceptionally high-fluence bursts of extreme solar particle events (SPE), such as the Carrington Event of 1859 and that inferred for AD 775. We calculate the altitude profiles of both energy deposition into the atmosphere and the absorbed radiation dose to assess this astrophysical threat to the potential high-altitude venusian biosphere. We find that at the top of the habitable zone (62 km altitude; 190 g/cm2 shielding depth) the radiation dose from the modelled Carrington Event with a hard spectrum (matched to the February 1956 SPE) is over 18,000 times higher than the background from GCR, and 50,000 times higher for the modelled 775 AD event. However, even though the flux of ionising radiation can be sterilizing high in the atmosphere, the total dose delivered at the top of the habitable zone by a worst-case SPE like the 775 AD event is 0.09 Gy, which is not likely to present a significant survival challenge. Nonetheless, the extreme ionisation could force atmospheric chemistry that may perturb a venusian biosphere in other ways. The energy deposition profiles presented here are also applicable to modelling efforts to understand how fundamental planetary atmospheric processes such as atmospheric chemistry, cloud microphysics and atmospheric electrical systems are affected by extreme solar particle events. The companion paper to this study, Constraints on a potential aerial biosphere on Venus: II. Solar ultraviolet radiation (Patel et al., in preparation), considers the threat posed by penetration of solar UV radiation. The results of these twin studies are based on Venus but are also applicable to extrasolar terrestrial planets near the inner edge of the circumstellar habitable zone.

A qualitative assessment of an abstinence-oriented therapeutic community for prisoners with substance use disorders in Kyrgyzstan.

PubMed

Azbel, Lyuba; Rozanova, Julia; Michels, Ingo; Altice, Frederick L; Stöver, Heino

2017-07-10

Kyrgyzstan, where HIV is concentrated in prisons and driven by injection drug use, provides a prison-based methadone maintenance therapy program as well as abstinence-oriented therapeutic community based on the 12-step model called the "Clean Zone." We aimed to qualitatively assess how prisoners navigate between these treatment options to understand the persistence of the Clean Zone despite a lack of evidence to support its effectiveness in treating opioid use disorders. We conducted an analysis of policy documents and over 60 h of participant observation in February 2016, which included focus groups with a convenience sample of 20 therapeutic community staff members, 110 prisoners across three male and one female prisons, and qualitative interviews with two former Clean Zone participants. Field notes containing verbatim quotes from participants were analyzed through iterative reading and discussion to understand how participants generally perceive the program, barriers to entry and retention, and implications for future treatment within prisons. Our analyses discerned three themes: pride in the mission of the Clean Zone, idealism regarding addiction treatment outcomes against all odds, and the demonization of methadone. Despite low enrollment and lack of an evidence base, the therapeutic community is buttressed by the strong support of the prison administration and its clients as an "ordered" alternative to what is seen as chaotic life outside of the Clean Zone. The lack of services for Clean Zone patients after release likely contributes to high rates of relapse to drug use. The Clean Zone would benefit from integration of stabilized methadone patients combined with a post-release program.

The Relationship Between Sexual Victimization and Year in School in U.S. Colleges: Investigating the Parameters of the "Red Zone".

PubMed

Cranney, Stephen

2015-10-01

It is the conventional wisdom among some universities that the highest risk of sexual assault is in the first or possibly second year in school. While initially belief in this pattern was primarily based on anecdote, recently some attempts have been made to more systematically and quantitatively test the existence of a "red zone," a time of heightened risk of sexual assault sometime near the beginning of a female student's time at the college. However, most of these studies have been conducted with relatively small convenience samples from single schools and have had conflicting results. Here, I test the red zone hypothesis using self-reported sexual victimization data with a large sample (~16,000) drawn from 22 schools as part of the Online College Social Life Survey. To investigate the specific mechanisms responsible for the red zone, I separately test for the existence of a red zone for four different types of sexual victimizations: physically forced intercourse, attempted forced intercourse, unwanted intercourse when incapacitated, and unwanted intercourse due to verbal pressure. Within these categories, I separately address sexual victimization that occurred while hanging out and sexual victimization during a party. Prior literature has emphasized the role of parties in the increased risk of assault for freshman. While I find some evidence for this in the higher estimates for sexual victimization at a party, the freshman effect remains for other types of sexual victimizations, suggesting that the red zone is not easily attributable to a single mechanistic cause, but to more generalizable factors. With one exception, I find that the red zone does not extend into the sophomore year. © The Author(s) 2014.

Cutting Zone Temperature Identification During Machining of Nickel Alloy Inconel 718

NASA Astrophysics Data System (ADS)

Czán, Andrej; Daniš, Igor; Holubják, Jozef; Zaušková, Lucia; Czánová, Tatiana; Mikloš, Matej; Martikáň, Pavol

2017-12-01

Quality of machined surface is affected by quality of cutting process. There are many parameters, which influence on the quality of the cutting process. The cutting temperature is one of most important parameters that influence the tool life and the quality of machined surfaces. Its identification and determination is key objective in specialized machining processes such as dry machining of hard-to-machine materials. It is well known that maximum temperature is obtained in the tool rake face at the vicinity of the cutting edge. A moderate level of cutting edge temperature and a low thermal shock reduce the tool wear phenomena, and a low temperature gradient in the machined sublayer reduces the risk of high tensile residual stresses. The thermocouple method was used to measure the temperature directly in the cutting zone. An original thermocouple was specially developed for measuring of temperature in the cutting zone, surface and subsurface layers of machined surface. This paper deals with identification of temperature and temperature gradient during dry peripheral milling of Inconel 718. The measurements were used to identification the temperature gradients and to reconstruct the thermal distribution in cutting zone with various cutting conditions.

Influence of Surface Features for Increased Heat Dissipation on Tool Wear

PubMed Central

Beno, Tomas; Hoier, Philipp; Wretland, Anders

2018-01-01

The critical problems faced during the machining process of heat resistant superalloys, (HRSA), is the concentration of heat in the cutting zone and the difficulty in dissipating it. The concentrated heat in the cutting zone has a negative influence on the tool life and surface quality of the machined surface, which in turn, contributes to higher manufacturing costs. This paper investigates improved heat dissipation from the cutting zone on the tool wear through surface features on the cutting tools. Firstly, the objective was to increase the available surface area in high temperature regions of the cutting tool. Secondly, multiple surface features were fabricated for the purpose of acting as channels in the rake face to create better access for the coolant to the proximity of the cutting edge. The purpose was thereby to improve the cooling of the cutting edge itself, which exhibits the highest temperature during machining. These modified inserts were experimentally investigated in face turning of Alloy 718 with high-pressure coolant. Overall results exhibited that surface featured inserts decreased flank wear, abrasion of the flank face, cutting edge deterioration and crater wear probably due to better heat dissipation from the cutting zone. PMID:29693579

K2 Finds Earth-Sized Planets Artist Concept

NASA Image and Video Library

2016-07-18

This artist's concept shows NASA's Kepler Space Telescope on its K2 mission. In July 2016, an international team of astronomers announced they had discovered more than 100 new planets using this telescope. The batch includes four planets in the size range of Earth that are orbiting a single dwarf star, depicted in this illustration. Two of these planets are too hot to support life as we know it, but two are in the star's "habitable" zone, where liquid water could exist on the surface. These small, rocky worlds are far closer to their star than Mercury is to our sun. But because the star is smaller and cooler than ours, its habitable zone is much closer. One of the two planets in the habitable zone, K2-72c, has a "year" about 15 Earth-days long -- the time it takes to complete one orbit. This closer planet is likely about 10 percent warmer than Earth. The slightly more distant planet in the habitable zone, K2-72e, has a year lasting 24 Earth days, and would be about 6 percent colder than Earth. http://photojournal.jpl.nasa.gov/catalog/PIA20698

A New Paradigm for Habitability in Planetary Systems: the Extremophilic Zone

NASA Astrophysics Data System (ADS)

Janot-Pacheco, E., Bernardes, L., Lage, C. A. S.

2014-03-01

More than a thousand exoplanets have been discovered so far. Planetary surface temperature may strongly depends on its albedo and geodynamic conditions. We have fed exoplanets from the Encyclopedia database with a comprehensive model of Earth's atmosphere and plate tectonics. As CO2 is the main agent responsible for the greenhouse effect, its partial pressure has been taken as a free parameter to estimate the surface temperature of some known planets. We also investigated the possible presence of "exomoons" belonging to giant planets in the Habitable Zone capable of harbour dynamic stability, to retain an atmosphere and to keep geodynamic activity for long time spans. Biological data on earthly micro-organisms classified as "extremophiles" indicate that such kind of microbial species could dwell on the surface of many exoplanets and exomoons. We thus propose an extension of the mainly astronomically defined "Habitable Zone" concept into the more astrobiologically one, the "Extremophililic Zone", that takes into account other parameters allowing survival of more robust life forms. This contribution comes from an ongoing project developed by a French-Brazilian colaboration in Astrophysics and Biophysics to search for living fingerprints in astrobiologically promising exoplanets.

Radon and radium in the ice-covered Arctic Ocean, and what they reveal about gas exchange in the sea ice zone.

NASA Astrophysics Data System (ADS)

Loose, B.; Kelly, R. P.; Bigdeli, A.; Moran, S. B.

2014-12-01

The polar sea ice zones are regions of high primary productivity and interior water mass formation. Consequently, the seasonal sea ice cycle appears important to both the solubility and biological carbon pumps. To estimate net CO2 transfer in the sea ice zone, we require accurate estimates of the air-sea gas transfer velocity. In the open ocean, the gas transfer velocity is driven by wind, waves and bubbles - all of which are strongly altered by the presence of sea ice, making it difficult to translate open ocean estimates of gas transfer to the ice zone. In this study, we present profiles of 222Rn and 226Ra throughout the mixed-layer and euphotic zone. Profiles were collected spanning a range of sea ice cover conditions from 40 to 100%. The profiles of Rn/Ra can be used to estimate the gas transfer velocity, but the 3.8 day half-life of 222Rn implies that mixed layer radon will have a memory of the past ~20 days of gas exchange forcing, which may include a range of sea ice cover conditions. Here, we compare individual estimates of the gas transfer velocity to the turbulent forcing conditions constrained from shipboard and regional reanalysis data to more appropriately capture the time history upper ocean Rn/Ra.

78 FR 13576 - Special Local Regulations and Safety Zones; Recurring Marine Events and Fireworks Displays Within...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-28

... area April--2nd Saturday St. Mary's College Seahawk Specified waters of St. Mary's Sprint River... regulations by adding 15 new annual recurring marine events, fireworks displays and revising event date(s) and... provide for the safety of life on navigable waters during these events, reduce the Coast Guard's...

Inter-Cultural Elements in the Collaboration between John G. Neihardt and Black Elk: Meeting in the "Contact Zones."

ERIC Educational Resources Information Center

Connal, Louise Rodriguez

The life of Nicholas Black Elk and the collaboration between him and John G. Neihardt on the book "Black Elk Speaks" presages or corresponds with current scholarly discussions of "transculturation." The diversity in society and the schools requires an enhancement of positive experiences in the inter-cultural "Contact…

THE DISTRIBUTION OF ORGANIC CARBON IN MAJOR COMPONENTS OF FORESTS LOCATED IN FIVE LIFE ZONES OF VENEZUELA

EPA Science Inventory

One of the major uncertainties concerning the role of tropical forests in the global carbon cycle is the lack of adequate data on the carbon content of all their components. The goal of this study was to contribute to filling this data gap by estimating the quantity of carbon in ...

77 FR 27120 - Safety Zone; Virginia Beach Oceanfront Air Show, Atlantic Ocean, Virginia Beach, VA

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-09

... restriction of vessel traffic is necessary to protect life, property and the environment during the fireworks... property and could cause significant injury or death to mariners observing the air shows. Due to the need... the Federal Register. The commenter suggested that the Coast Guard add a chart to the regulation to...

Avian research on Experimental Forests and Ranges: Emergent themes, opportunities, and challenges

Treesearch

Scott H. Stoleson; David I. King; Monica. Tomosy

2011-01-01

Since 1908, U.S. Forest Service Experimental Forests and Ranges have been dedicated to long-term inter-disciplinary research on a variety of ecological and management questions. They encompass a wide diversity of life zones and ecoregions, and provide access to research infrastructure, opportunities for controlled manipulations, and integration with other types of long...

Conservation of biodiversity: a useful paradigm for forest ecosystem management.

Treesearch

A.B. Carey; R.O. Curtis

1996-01-01

The coniferous forests of the Western Hemlock Zone of western Oregon and western Washington are remarkable in the longevity and stature of their trees, long intervals between stand-replacing events, capacity to produce timber, diversity of life forms and species, and controversy over their management. The controversy is hardly new (Overton and Hunt 1974). But the...

75 FR 18404 - Safety Zone; FRONTIER DISCOVERER, Outer Continental Shelf Drillship, Chukchi and Beaufort Sea...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-12

... on location in order to drill exploratory wells at various prospects located in the Chukchi and Beaufort Sea Outer Continental Shelf, Alaska, during the 2010 drilling season. The purpose of the temporary... allisions, oil spills, and releases of natural gas, and thereby protect the safety of life, property, and...

Forest Floor Decomposition Following Hurricane Litter Inputs in Several Puerto Rican Forests

Treesearch

Rebecca Ostertag; Frederick N. Scatena; Whendee L. Silver

2003-01-01

Hurricanes affect ecosystem processes by altering resource availability and heterogeneity, but the spatial and temporal signatures of these events on biomass and nutrient cycling processes are not well understood. We examined mass and nutrient inputs of hurricane-derived litter in six tropical forests spanning three life zones in northeastern Puerto Rico after the...

Effects of Model Choice and Forest Structure on Inventory-Based Estimations of Puerto Rican Forest Biomass.

Treesearch

THOMAS J. BRANDEIS; MARIA DEL ROCIO SUAREZ ROZO

2005-01-01

Total aboveground live tree biomass in Puerto Rican lower montane wet, subtropical wet, subtropical moist and subtropical dry forests was estimated using data from two forest inventories and published regression equations. Multiple potentially-applicable published biomass models existed for some forested life zones, and their estimates tended to diverge with increasing...

Effects of model choice and forest structure on inventory-based estimations of Puerto Rican forest biomass

Treesearch

Thomas J. Brandeis; Maria Del Rocio; Suarez Rozo

2005-01-01

Total aboveground live tree biomass in Puerto Rican lower montane wet, subtropical wet, subtropical moist and subtropical dry forests was estimated using data from two forest inventories and published regression equations. Multiple potentially-applicable published biomass models existed for some forested life zones, and their estimates tended to diverge with increasing...

HYPOXIA IN THE GULF OF MEXICO: ASSESSING AND MANAGING RISKS FROM NONPOINT SOURCE POLLUTANTS IN THE MISSISSIPPI RIVER BASIN

EPA Science Inventory

. Hypoxia is the condition in which dissolved oxygen levels are below that necessary to sustain most animal life. The largest zone of oxygen depletion in U.S. coastal waters is found in the northern Gulf of Mexico (NGOM) on the Louisiana/Texas continental shelf. In response to...

Influence of altitude and aspect on daily variations in factors of forest fire danger

Treesearch

G. Lloyd. Hayes

1941-01-01

Altitude, in broad subdivisions, exerts recognized and well-understood effects on climate. Aspect further modifies the altitudinal influence. Many publications have dealt with the interrelations of these geographic factors with climate and life zones or have discussed variations of individual weather elements as influenced by local altitude and aspect differences and...

Expression of functional traits during seedling establishment in two populations of Pinus ponderosa from contrasting climates

Treesearch

K. L. Fenn; F. C. Meinzer; K. A. McCulloh; D. R. Woodruff; D. E. Marias

2015-01-01

First-year tree seedlings represent a particularly vulnerable life stage and successful seedling establishment is crucial for forest regeneration. We investigated the extent to which Pinus ponderosa P. & C. Lawson populations from different climate zones exhibit differential expression of functional traits that may facilitate their establishment. Seeds from two...

The frontier beneath our feet

NASA Astrophysics Data System (ADS)

Grant, Gordon E.; Dietrich, William E.

2017-04-01

Following the simple question as to where water goes when it rains leads to one of the most exciting frontiers in earth science: the critical zone—Earth's dynamic skin. The critical zone extends from the top of the vegetation canopy through the soil and down to fresh bedrock and the bottom of the groundwater. Only recently recognized as a distinct zone, it is challenging to study because it is hard to observe directly, and varies widely across biogeoclimatic regions. Yet new ideas, instruments, and observations are revealing surprising and sometimes paradoxical insights, underscoring the value of field campaigns and long-term observatories. These insights bear directly on some of the most pressing societal problems today: maintaining healthy forests, sustaining streamflow during droughts, and restoring productive terrestrial and aquatic ecosystems. The critical zone is critical because it supports all terrestrial life; it is the nexus where water and carbon is cycled, vegetation (hence food) grows, soil develops, landscapes evolve, and we live. No other frontier is so close to home.

The Mojave vadose zone: a subsurface biosphere analogue for Mars.

PubMed

Abbey, William; Salas, Everett; Bhartia, Rohit; Beegle, Luther W

2013-07-01

If life ever evolved on the surface of Mars, it is unlikely that it would still survive there today, but as Mars evolved from a wet planet to an arid one, the subsurface environment may have presented a refuge from increasingly hostile surface conditions. Since the last glacial maximum, the Mojave Desert has experienced a similar shift from a wet to a dry environment, giving us the opportunity to study here on Earth how subsurface ecosystems in an arid environment adapt to increasingly barren surface conditions. In this paper, we advocate studying the vadose zone ecosystem of the Mojave Desert as an analogue for possible subsurface biospheres on Mars. We also describe several examples of Mars-like terrain found in the Mojave region and discuss ecological insights that might be gained by a thorough examination of the vadose zone in these specific terrains. Examples described include distributary fans (deltas, alluvial fans, etc.), paleosols overlain by basaltic lava flows, and evaporite deposits.

Critical concerns in Iraq/Afghanistan war veteran-forensic interface: combat-related postdeployment criminal violence.

PubMed

Sreenivasan, Shoba; Garrick, Thomas; McGuire, James; Smee, Daniel E; Dow, Daniel; Woehl, Daniel

2013-01-01

Identifying whether there is a nexus between Iraq and Afghanistan combat injuries and civilian violence on return from deployment is complicated by differences in reactions of individuals to combat exposure, the overlapping effects of traumatic brain injury (TBI) and posttraumatic stress disorder (PTSD), and the low base rate of civilian violence after combat exposure. Moreover, the overall prevalence of violence among returning Iraq and Afghanistan combat war veterans has not been well documented. Malingered symptoms and either exaggeration or outright fabrication of war zone exposure are challenges to rendering forensic opinions, with the risk reduced by accessing military documents that corroborate war zone duties and exposure. This article serves as a first step toward understanding what may potentiate violence among returning Iraq and Afghanistan veterans. We offer a systematic approach toward the purpose of forensic case formulation that addresses whether combat duty/war zone exposure and associated clinical conditions are linked to criminal violence on return to civilian life.

The Associations between Self-Reported Exposure to the Chernobyl Nuclear Disaster Zone and Mental Health Disorders in Ukraine.

PubMed

Bolt, Matthew A; Helming, Luralyn M; Tintle, Nathan L

2018-01-01

In 1986, Reactor 4 of the Chernobyl nuclear power plant near Pripyat, Ukraine exploded, releasing highly-radioactive materials into the surrounding environment. Although the physical effects of the disaster have been well-documented, a limited amount of research has been conducted on association of the disaster with long-term, clinically-diagnosable mental health disorders. According to the diathesis-stress model, the stress of potential and unknown exposure to radioactive materials and the ensuing changes to ones life or environment due to the disaster might lead those with previous vulnerabilities to fall into a poor state of mental health. Previous studies of this disaster have found elevated symptoms of stress, substance abuse, anxiety, and depression in exposed populations, though often at a subclinical level. With data from The World Mental Health Composite International Diagnostic Interview, a cross-sectional large mental health survey conducted in Ukraine by the World Health Organization, the mental health of Ukrainians was modeled with multivariable logistic regression techniques to determine if any long-term mental health disorders were association with reporting having lived in the zone affected by the Chernobyl nuclear disaster. Common classes of psychiatric disorders were examined as well as self-report ratings of physical and mental health. Reporting that one lived in the Chernobyl-affected disaster zone was associated with a higher rate of alcohol disorders among men and higher rates of intermittent explosive disorders among women in a prevalence model. Subjects who lived in the disaster zone also had lower ratings of personal physical and mental health when compared to controls. Stress resulting from disaster exposure, whether or not such exposure actually occurred or was merely feared, and ensuing changes in life circumstances is associated with increased rates of mental health disorders. Professionals assisting populations that are coping with the consequences of disaster should be aware of possible increases in psychiatric disorders as well as poorer perceptions regarding personal physical and mental health.

What we could learn from observations of terrestrial exoplanets

NASA Astrophysics Data System (ADS)

Meadows, Victoria; Schwieterman, Edward; Arney, Giada; Lustig-Yaeger, Jacob; Lincowski, Andrew; Robinson, Tyler D.; Deming, Drake; NASA Astrobiology Institute - Virtual Planetary Laboratory

2016-10-01

Observations of terrestrial exoplanet environments remain an important frontier in comparative planetology. Studies of habitable zone terrestrial planets will set our own Earth in a broader context. Hot, post-runaway terrestrial exoplanets can provide insights into terrestrial planet evolution - and may reveal planetary processes that could mimic signs of life, such as photochemically-produced oxygen. While transmission spectroscopy observations of terrestrial planet atmospheres with JWST will be extremely challenging, they will afford our first chance to characterize the atmospheres of planets orbiting in the habitable zone of M dwarfs. However, due to the effects of refraction, clouds and hazes, JWST will likely sample the stratospheres of habitable zone terrestrial planets, and will not be able to observe the planetary surface or near-surface atmosphere. These limitations will hamper the search for signs of habitability and life, by precluding detection of water vapor in the deep atmosphere, and confining biosignature searches to gases that are prevalent in the stratosphere, such as evenly-mixed O2, or photochemical byproducts of biogenic gases. In contrast, direct imaging missions can potentially probe the entire atmospheric column and planetary surface, and can typically obtain broader wavelength coverage for habitable zone planets orbiting more Sun-like stars, complementing the M dwarf planet observations favored by transmission spectroscopy. In this presentation we will show results from theoretical modeling of terrestrial exoplanet environments for habitable Earth-like, early Earth and highly-evolved hot terrestrial planets - with photochemistry and climates that are driven by host stars of different spectral types. We will also present simulated observations of these planets for both transmission (JWST) and direct imaging (LUVOIR-class) observations. These photometric measurements and spectra help us identify the most - and least - observable features of these planetary environments, and illuminate the strengths and limitations of each class of observation for future terrestrial planet characterization studies.

Vegetation ecology and carbon sequestration potential of shrubs in tropics of Chhattisgarh, India.

PubMed

Jhariya, Manoj Kumar

2017-09-25

Tropical forests are well known to have great species diversity and contribute substantial share in terrestrial carbon (C) stocks worldwide. Shrubs are long-neglected life form in the forest ecosystem, playing many roles in the forest and human life. Shrub has great impact on vegetation attributes which in turn modify the C storage and capture. In the present investigation, an attempt has been made to explore the dynamics of shrub species in four fire regimes, viz. high, medium, low, and no fire zones of Bhoramdeo Wildlife Sanctuary of Kawardha forest division (Chhattisgarh), India. The variations in structure, diversity, biomass, productivity, and C sequestration potential in all the sites were quantified. The density and basal area of shrub varied from 1250 to 3750 individuals ha -1 and 2.79 to 4.92 m 2  ha -1 , respectively. The diversity indices showed that the value of Shannon index was highest in medium fire zone (3.77) followed by high, low, and no fire zones as 3.25, 3.12, and 2.32, respectively. The value of Simpson's index or concentration of dominance (Cd) ranged from 0.08 to 0.20, species richness from 0.56 to 1.58, equitability from 1.41 to 1.44, and beta diversity from 1.50 to 4.20, respectively. The total biomass and C storage ranged from 6.82 to 15.71 and from 2.93 to 6.76 t ha -1 , respectively. The shrub density, importance value index (IVI), and abundance to frequency ratio (A/F) significantly correlated between high fire and medium fire zone. The basal area was found to be significantly positively correlated between high fire and medium fire, and low and no fire zones, respectively. Two-way cluster analysis reflected various patterns of clustering due to influence of the forest fire which showed that some species have distant clustering while some have smaller cluster. Principal component analysis (PCA) reflects variable scenario with respect to shrub layer. Ventilago calyculata and Zizyphus rotundifolia showed higher correlation between themselves in terms of basal area (BA). The total shrub production was 1.59-3.53 t ha -1  year -1 while the C sequestration potential of 0.71-1.57 t ha -1  year -1 under different fire regimes. Shrub community in the medium fire zone reflected higher productivity and higher C sequestration in comparison to other fire zone. Among the different plant parts, the biomass accumulation ratio was highest in the root of shrub community among various fire regimes. Screening of species for restoration and different land-use pattern on the basis of biomass accumulation and carbon sequestering potential would be an effective strategy for decision-making in sustainable forest management.

The impact of an efficient collection sites location on the zoning phase in municipal solid waste management

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ghiani, Gianpaolo, E-mail: gianpaolo.ghiani@unisalento.it; Manni, Andrea, E-mail: andrea.manni@unisalento.it; Manni, Emanuele, E-mail: emanuele.manni@unisalento.it

2014-11-15

Highlights: • We study the problems of locating collection areas and zoning the service territory in a municipal waste management system. • We investigate the impact that an efficient collection sites location has on the subsequent zoning phase. • On a real-world test case, we show that the proposed approach could allow achieving significant monetary savings. - Abstract: In this paper, we study two decisional problems arising when planning the collection of solid waste, namely the location of collection sites (together with bin allocation) and the zoning of the service territory, and we assess the potential impact that an efficientmore » location has on the subsequent zoning phase. We first propose both an exact and a heuristic approach to locate the unsorted waste collection bins in a residential town, and to decide the capacities and characteristics of the bins to be located at each collection site. A peculiar aspect we consider is that of taking into account the compatibility between the different types of bins when allocating them to collection areas. Moreover, we propose a fast and effective heuristic approach to identify homogeneous zones that can be served by a single collection vehicle. Computational results on data related to a real-life instance show that an efficient location is fundamental in achieving consistent monetary savings, as well as a reduced environmental impact. These reductions are the result of one vehicle less needed to perform the waste collection operations, and an overall traveled distance reduced by about 25% on the average.« less

Soft-water zone in the Chicot Aquifer, Bayou Teche area, Louisiana

USGS Publications Warehouse

Hosman, R.L.

1974-01-01

Test drilling in the vicinity of Bayou Teche in St. Martin Parish in southern Louisiana has disclosed a zone of soft water in the basal unit of the Chicot aquifer; the Chicot aquifer system blankets all southwestern Louisiana. Fresh water, which is defined as containing 250 milligrams per liter chloride or less, in the Chicot aquifer is characteristically hard and high in iron concentration; in this area the hardness is generally 200-300 milligrams per liter. The soft-water zone, containing water with a hardness of less than 60 milligrams per liter, is anomalous and occurs in an area where the basal part of the aquifer is separated from the main body of the aquifer by a thick clay layer. The zone has been mapped in parts of St. Martin and adjoining Lafayette Parishes. Although the exact areal extent of the zone cannot be determined with available data, it appears to be sufficiently large that the soft water should prove to be an important asset to the area. The water could be used by itself or mixed with either hard or slightly salty water (more than 250 milligrams per liter chloride) to provide a blend that would require little or no treatment for most purposes. Because of the proximity of salty water in much of the area, careful planning and monitoring will be necessary to maintain the soft-water zone as a dependable supply of usable water. The soft water appears to be an exhaustible supply; however, its useful life as a resource can be maximized by proper management.

Environmental drivers of soil microbial community structure and function at the Avon River Critical Zone Observatory.

PubMed

Gleeson, Deirdre; Mathes, Falko; Farrell, Mark; Leopold, Matthias

2016-11-15

The Critical Zone is defined as the thin, permeable layer from the tops of the trees to the bottom of the bedrock that sustains terrestrial life on Earth. The geometry and shape of the various weathering zones are known as the critical zone architecture. At the centre of the Critical Zone are soils and the microorganisms that inhabit them. In Western Australia, the million-year-old stable weathering history and more recent lateral erosion during the past hundreds of thousands of years have created a geomorphic setting where deep weathering zones are now exposed on the surface along the flanks of many lateritic hills. These old weathering zones provide diverse physical and chemical properties that influence near surface pedologic conditions and thus likely shape current surface microbiology. Here, we present data derived from a small lateritic hill on the UWA Farm Ridgefield. Spatial soil sampling revealed the contrasting distribution patterns of simple soil parameters such as pH (CaCl2) and electric conductivity. These are clearly linked with underlying changes of the critical zone architecture and show a strong contrast with low values of pH3.3 at the top of the hill to pH5.3 at the bottom. These parameters were identified as major drivers of microbial spatial variability in terms of bacterial and archaeal community composition but not abundance. In addition, we used sensitive (14)C labelling to assess turnover of three model organic nitrogen compounds - an important biogeochemical functional trait relating to nutrient availability. Though generally rapid and in the order of rates reported elsewhere (t½<5h), some points in the sampling area showed greatly reduced turnover rates (t½>10h). In conclusion, we have shown that the weathering and erosion history of ancient Western Australia affects the surface pedology and has consequences for microbial community structure and function. Copyright © 2016 Elsevier B.V. All rights reserved.

Demographic and life history characteristics influence the cytonuclear composition of mosquitofish populations

USGS Publications Warehouse

Scribner, Kim T.; Avise, John C.; Beaumont, A.

1994-01-01

Experimental laboratory crosses and population experiments reveal significant differences in individual life-history traits and population demography between two related species of mosquitofish, Gambusia affinis and G. holbrooki. With respect to life-history traits, progeny from G. holbrooki exhibit larger size at birth and earlier age at sexual maturity than do progeny from G. affinis parents. With respect to demography, populations of G. holbrooki exhibit higher recruitment and carrying capacity and loser overwinter mortality than do populations of G. affinis. These differences help t explain the dramatic changes in cytonuclear genotype frequency observed in replicated experimental hybrid populations of Gambusia monitored over 52 weeks. These experimental results are interpreted in the context of introgression patterns previously studied indirectly from distributions of cytonuclear genotypes in a natural mosquitofish hybrid zone.

Estudios de resistencia al estrés de una bacteria poliextremófila relevante para estudios de habitabilidad en planetas solares y extrasolares

NASA Astrophysics Data System (ADS)

Maizel, D.; Alché, L.; Mauas, P. J. D.

2017-10-01

Recent astrobiology studies have focused in the search for life in Earth-like planets within the Habitable Zone. In an attempt to find possible extraterrestrial forms of life, it becomes fundamental to study extreme life in our own planet, known as ``extremophiles''. In the present work, a study was conducted regarding the capability of the poly-extremophilic bacterial strain Brevibacterium linens AE038-8 to resist different stress factors. Strain AE038-8 was able to grow in presence of high salt concentrations and different doses of UV radiation. In addition to the extreme resistance observed in previous research of this strain, we propose B. linens AE038-8 as a model microorganism for astrobiology studies.

Zones of life in the subsurface of hydrothermal vents: A synthesis

NASA Astrophysics Data System (ADS)

Larson, B. I.; Houghton, J.; Meile, C. D.

2011-12-01

Subsurface microbial communities in Mid-ocean Ridge (MOR) hydrothermal systems host a wide array of unique metabolic strategies, but the spatial distribution of biogeochemical transformations is poorly constrained. Here we present an approach that reexamines chemical measurements from diffuse fluids with models of convective transport to delineate likely reaction zones. Chemical data have been compiled from bare basalt surfaces at a wide array of mid-ocean ridge systems, including 9°N, East Pacific Rise, Axial Seamount, Juan de Fuca, and Lucky Strike, Mid-Atlantic Ridge. Co-sampled end-member fluid from Ty (EPR) was used to constrain reaction path models that define diffuse fluid compositions as a function of temperature. The degree of mixing between hot vent fluid (350 deg. C) and seawater (2 deg. C) governs fluid temperature, Fe-oxide mineral precipitation is suppressed, and aqueous redox reactions are prevented from equilibrating, consistent with sluggish kinetics. Quartz and pyrite are predicted to precipitate, consistent with field observations. Most reported samples of diffuse fluids from EPR and Axial Seamount fall along the same predicted mixing line only when pyrite precipitation is suppressed, but Lucky Strike fluids do not follow the same trend. The predicted fluid composition as a function of temperature is then used to calculate the free energy available to autotrophic microorganisms for a variety of catabolic strategies in the subsurface. Finally, the relationships between temperature and free energy is combined with modeled temperature fields (Lowell et al., 2007 Geochem. Geophys., Geosys.) over a 500 m x 500 m region extending downward from the seafloor and outward from the high temperature focused hydrothermal flow to define areas that are energetically most favorable for a given metabolic process as well as below the upper temperature limit for life (~120 deg. C). In this way, we can expand the relevance of geochemical model predictions of bioenergetics by predicting functionally-defined 'Zones of Life' and placing them spatially within the boundary of the 120 deg. C isotherm, estimating the extent of subsurface biosphere beneath mid-ocean ridge hydrothermal systems. Preliminary results indicate that methanogenesis yields the most energy per kg of vent fluid, consistent with the elevated CH4(aq) seen at all three sites, but may be constrained by temperatures too hot for microbial life while available energy from the oxidation of Fe(II) peaks near regions of the crust that are more hospitable.

Unexpected ancestry of Populus seedlings from a hybrid zone implies a large role for postzygotic selection in the maintenance of species.

PubMed

Lindtke, Dorothea; Gompert, Zachariah; Lexer, Christian; Buerkle, C Alex

2014-09-01

In the context of potential interspecific gene flow, the integrity of species will be maintained by reproductive barriers that reduce genetic exchange, including traits associated with prezygotic isolation or poor performance of hybrids. Hybrid zones can be used to study the importance of different reproductive barriers, particularly when both parental species and hybrids occur in close spatial proximity. We investigated the importance of barriers to gene flow that act early vs. late in the life cycle of European Populus by quantifying the prevalence of homospecific and hybrid matings within a mosaic hybrid zone. We obtained genotypic data for 11 976 loci from progeny and their maternal parents and constructed a Bayesian model to estimate individual admixture proportions and hybrid classes for sampled trees and for the unsampled pollen parent. Matings that included one or two hybrid parents were common, resulting in admixture proportions of progeny that spanned the whole range of potential ancestries between the two parental species. This result contrasts strongly with the distribution of admixture proportions in adult trees, where intermediate hybrids and each of the parental species are separated into three discrete ancestry clusters. The existence of the full range of hybrids in seedlings is consistent with weak reproductive isolation early in the life cycle of Populus. Instead, a considerable amount of selection must take place between the seedling stage and maturity to remove many hybrid seedlings. Our results highlight that high hybridization rates and appreciable hybrid fitness do not necessarily conflict with the maintenance of species integrity. © 2014 John Wiley & Sons Ltd.

International PV QA Task Force's Proposed Comparative Rating System for PV Modules: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wohlgemuth, J.; Kurtz, S.

The International PV Quality Assurance Task Force is developing a rating system that provides comparative information about the relative durability of PV modules. Development of accelerated stress tests that can provide such comparative information is seen as a major step toward being able to predict PV module service life. This paper will provide details of the ongoing effort to determine the format of such an overall module rating system. The latest proposal is based on using three distinct climate zones as defined in IEC 60721-2-1 for two different mounting systems. Specific stresses beyond those used in the qualification tests aremore » being developed for each of the selected climate zones.« less

The Social ecology of Madrid: Stratification in comparative perspective.

PubMed

Abrahamson, M; Johnson, P

1974-08-01

This paper examines the characteristics of residential zones in Madrid, Spain. The primary difference between zones is found to lie in a new bourgeoisie life-style dimension. Working women are found to be the best indicator of this dimension, which also involves servants, natives of Madrid and high degrees of literacy. Fertility-related considerations, however, are unrelated to working women, and this is explained as due to the availability of domestic help and "women-oriented" working arrangements. Fertility and socioeconomic status are found to be interrelated and constitute a second dimension of residential segregation. In conclusion, Madrid is examined in relation to both more and less industrialized cities, leading to a further modification of social area theory contentions concerning the ecology of stratification in developing cities.

Life Cycle Environmental Impacts of Disinfection Technologies Used in Small Drinking Water Systems.

PubMed

Jones, Christopher H; Shilling, Elizabeth G; Linden, Karl G; Cook, Sherri M

2018-03-06

Small drinking water systems serve a fifth of the U.S. population and rely heavily on disinfection. While chlorine disinfection is common, there is interest in minimizing chemical addition, especially due to carcinogenic disinfection byproducts and chlorine-resistant pathogens, by using ultraviolet technologies; however, the relative, broader environmental impacts of these technologies are not well established, especially in the context of small (<10 000 people) water systems. The objective of this study was to identify environmental trade-offs between chlorine and ultraviolet disinfection via comparative life cycle assessment. The functional unit was the production of 1 m 3 of drinking water to U.S. Treatment included cartridge filtration followed by either chlorine disinfection or ultraviolet disinfection with chlorine residual addition. Environmental performance was evaluated for various chlorine contact zone materials (plastic, concrete, steel), ultraviolet validation factors (1.2 to 4.4), and electricity sources (renewable; U.S. average, high, and low impact grids). Performance was also evaluated when filtration and chlorine residual were not required. From a life cycle assessment perspective, replacing chlorine with UV was preferred only in a limited number of cases (i.e., high pumping pressure but filtration is not required). In all others, chlorine was environmentally preferred, although some contact zone materials and energy sources had an impact on the comparison. Utilities can use these data to inform their disinfection technology selection and operation to minimize environmental and human health impacts.

Clinical and ocular motor analysis of the infantile nystagmus syndrome in the first 6 months of life.

PubMed

Hertle, R W; Maldanado, V K; Maybodi, M; Yang, D

2002-06-01

The infantile nystagmus syndrome (INS) usually begins in infancy and may or may not be associated with visual sensory system abnormalities. Little is known about its specific waveforms in the first 6 months of life or their relation to the developing visual system. This study identifies the clinical and ocular motility characteristics of the INS and establishes the range of waveforms present in the first 6 months of life. 27 infants with involuntary ocular oscillations typical of INS are included in this analysis. They were evaluated both clinically and with motility recordings. Eye movement analysis was performed off line from computer analysis of digitised data. Variables analysed included age, sex, vision, ocular abnormalities, head position, and null zone, neutral zone characteristics, symmetry, conjugacy, waveforms, frequencies, and foveation times. Ages ranged from 3 to 6.5 months (average 4.9 months). 15 patients (56%) had abnormal vision for age, nine (33%) had strabismus, five (19%) had an anomalous head posture, 13 (48%) had oculographic null and neutral positions, nine (33%) had binocular asymmetry, and only two showed consistent dysconjugacy. Average binocular frequency was 3.3 Hz, monocular frequency 6.6 Hz. Average foveation periods were longer and more "jerk" wave forms were observed in those patients with normal vision. Common clinical characteristics and eye movement waveforms of INS begin in the first few months of infancy and waveform analysis at this time may help with both diagnosis and visual status.

Hunger influenced life expectancy in war-torn Sub-Saharan African countries.

PubMed

Uchendu, Florence N

2018-04-27

Malnutrition is a global public health problem especially in developing countries experiencing war/conflicts. War might be one of the socio-political factors influencing malnutrition in Sub-Saharan African (SSA) countries. This study aims at determining the influence of war on corruption, population (POP), number of population malnourished (NPU), food security and life expectancy (LE) in war-torn SSA countries (WTSSA) by comparing their malnutrition indicators. Fourteen countries in WTSSA were stratified into zones according to war incidences. Countries' secondary data on population (POP), NPU, Food Security Index (FSI), corruption perceptions index (CPI), Global Hunger Index (GHI) and LE were obtained from global published data. T test, multivariate and Pearson correlation analyses were performed to determine the relationship between CPI, POP, GHI, FSI, NPU, male LE (MLE) and female LE (FLE) in WTSSA at p < .05. Data were presented in tables, means, standard deviation and percentages. Mean NPU, CPI, GHI, POP, FSI, MLE and FLE in WTSSA were 5.0 million, 28.3%, 18.2%, 33.8 million, 30.8%, 54.7 years and 57.1 years, respectively. GHI significantly influenced LE in both male and female POP in WTSSA. NPU, CPI, FSI, GHI and FLE were not significantly different according to zones except in MLE. Malnutrition indicators were similarly affected in WTSSA. Hunger influenced life expectancy. Policies promoting good governance, equity, peaceful co-existence, respect for human right and adequate food supply will aid malnutrition eradication and prevent war occurrences in Sub-Saharan African countries.

Full chain life cycle assessment of greenhouse gases and energy demand for canola-derived jet fuel in North Dakota, United States

USDA-ARS?s Scientific Manuscript database

The success of long-term sustainable biofuel production on agricultural lands is still questionable. To this end, we investigated the effects of crop prices on the changes of agricultural land use for biofuel canola production in three wheat crop management zones in North Dakota. The effects of cano...

THE QUANTITY AND TURNOVER OF DEAD WOOD IN PERMANENT FOREST PLOTS IN SIX LIFE ZONES OF VENEZUELA

EPA Science Inventory

Dead wood can be an important component of the carbon pool in many forests, but few measurements have been made of this pool in tropical forests. To fill this gap, we determined the quantity of dead wood (downed and standing dead) in 25 long-term (up to 30 yr) permanent forest pl...

Contested Urban Spaces: Exploring the Analytics of Young Persons' Experiences of Living in Glasgow's Deprived Zones

ERIC Educational Resources Information Center

Holligan, Chris; Deuchar, Ross

2011-01-01

This paper reports findings from an exploratory study of mainly young people's verbally articulated perceptions of urban life in Glasgow, Scotland. The focus is upon areas of deprivation where territory and social capital is contested and whose meanings are possibly only partially grasped by our informants. Their personal knowledge of violence and…

Potential effects of acid precipitation on soils in the humid temperate zone

Treesearch

C. R. Frink; G. K. Voigt

1976-01-01

Acid precipitation is not a new phenomenon. As long as water has fallen on the surface of the earth it has probably contained varying amounts of oxides of carbons, nitrogen and sulfur that increase hydrogen ion activity. This was certainly true when volcanism prevailed. With the appearance of life spasmodic geologic expulsions of elements into the atmosphere were...

The status of Puerto Rico's forests, 2003

Treesearch

Thomas J. Brandeis; Eileen H. Helmer; Sonja N. Oswalt

2007-01-01

Puerto Rico’s forest cover continues to increase and is now 57 percent for mainland Puerto Rico, 85 percent for Vieques, and 88 percent for Culebra. Subtropical dry forest occupies 50 346 ha, 6832 ha, 2591 ha, and 6217 ha on the islands of Puerto Rico, Vieques, Culebra, and Mona, respectively. Subtropical moist forest, the most prevalent forested life zone on...

The Rocky Shore. A Learning Experience for Coastal and Oceanic Awareness Studies, No. 225. [Project COAST].

ERIC Educational Resources Information Center

Delaware Univ., Newark. Coll. of Education.

This unit is designed to be used by students in biology classes in secondary schools. Emphasized in the unit are coastal life zones, plants and animals that live in these areas, and factors influencing the lives of the organisms. Included in the unit are evaluation materials, instructional objectives, student background information, masters for…

The Lands of New Mexico.

ERIC Educational Resources Information Center

Swadesh, Frances Leon; And Others

New Mexico, the fifth largest state, measures 390 miles from north to south and 350 miles from east to west. Six of the 7 life zones found in the U.S. are represented within the State's 77,866,240 acres. Its population has tended to congregate at altitudes of 7,000 feet and below, especially in areas where water is available. This booklet,…

Tree Growth in Several Tropical Forests of Puerto Rico

Treesearch

Peter L. Weaver

1979-01-01

About 2400 individual stems > 4.1 cm d.b.h., and representing about 100 species, from six plots in three Life Zones, some with edaphic variationand/orsilviculturaltreatment, scattered throughout Puerto Rico, were studied for varying periods, usually ranging from 24 through 30 years but in one instance for only 2 years. Also, more than 11,000 mangrove stems > 1 cm...

77 FR 30507 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Reef Fish Fishery of the Gulf of...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-23

... the Caribbean, Gulf of Mexico, and South Atlantic; Reef Fish Fishery of the Gulf of Mexico; Exempted... and retention. This study, to be conducted in the exclusive economic zone (EEZ) of the Gulf of Mexico (Gulf), is intended to better document the age structure and life history of fish associated with...

78 FR 37710 - Safety Zone; Wicomico Community Fireworks Rain Date, Great Wicomico River, Heathsville, VA

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-24

...: Coast Guard, DHS. ACTION: Temporary Final rule. SUMMARY: The Coast Guard is establishing a temporary... event Rain Date. This action is necessary to provide for the safety of life on navigable waters during.... DATES: This rule is effective on July 7, 2013, from 9 p.m. to 10 p.m. ADDRESSES: Documents indicated in...

78 FR 41844 - Safety Zone; Fairfield Estates Fireworks Display, Atlantic Ocean, Sagaponack, NY

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-12

... Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a temporary safety... fireworks display. This action is necessary to provide for the safety of life on navigable waters during the... rule is effective from 8:30 p.m. August 1, 2013, until 10:30 p.m. on August 2, 2013. This rule will be...

An Investigation on the Wear Resistance and Fatigue Behaviour of Ti-6Al-4V Notched Members Coated with Hydroxyapatite Coatings

PubMed Central

Oskouei, Reza H; Fallahnezhad, Khosro; Kuppusami, Sushmitha

2016-01-01

In this study, surface properties of Ti-6Al-4V alloy coated with hydroxyapatite coatings were investigated. Wear resistance and fatigue behaviour of samples with coating thicknesses of 10 and 50 µm as well as uncoated samples were examined. Wear experiments demonstrated that the friction factor of the uncoated titanium decreased from 0.31 to 0.06, through a fluctuating trend, after 50 cycles of wear tests. However, the friction factor of both the coated samples (10 and 50 µm) gradually decreased from 0.20 to 0.12 after 50 cycles. At the end of the 50th cycle, the penetration depth of the 10 and 50 µm coated samples were 7.69 and 6.06 µm, respectively. Fatigue tests showed that hydroxyapatite coatings could improve fatigue life of a notched Ti-6Al-4V member in both low and high cycle fatigue zones. It was understood, from fractography of the fracture surfaces, that the fatigue zone of the uncoated specimens was generally smaller in comparison with that of the coated specimens. No significant difference was observed between the fatigue life of coated specimens with 10 and 50 µm thicknesses. PMID:28787911

Interdisciplinary modeling and analysis to reduce loss of life from tsunamis

NASA Astrophysics Data System (ADS)

Wood, N. J.

2016-12-01

Recent disasters have demonstrated the significant loss of life and community impacts that can occur from tsunamis. Minimizing future losses requires an integrated understanding of the range of potential tsunami threats, how individuals are specifically vulnerable to these threats, what is currently in place to improve their chances of survival, and what risk-reduction efforts could be implemented. This presentation will provide a holistic perspective of USGS research enabled by recent advances in geospatial modeling to assess and communicate population vulnerability to tsunamis and the range of possible interventions to reduce it. Integrated research includes efforts to characterize the magnitude and demography of at-risk individuals in tsunami-hazard zones, their evacuation potential based on landscape conditions, nature-based mitigation to improve evacuation potential, evacuation pathways and population demand at assembly areas, siting considerations for vertical-evacuation refuges, community implications of multiple evacuation zones, car-based evacuation modeling for distant tsunamis, and projected changes in population exposure to tsunamis over time. Collectively, this interdisciplinary research supports emergency managers in their efforts to implement targeted risk-reduction efforts based on local conditions and needs, instead of generic regional strategies that only focus on hazard attributes.

Improvement of Steam Turbine Operational Performance and Reliability with using Modern Information Technologies

NASA Astrophysics Data System (ADS)

Brezgin, V. I.; Brodov, Yu M.; Kultishev, A. Yu

2017-11-01

The report presents improvement methods review in the fields of the steam turbine units design and operation based on modern information technologies application. In accordance with the life cycle methodology support, a conceptual model of the information support system during life cycle main stages (LC) of steam turbine unit is suggested. A classifying system, which ensures the creation of sustainable information links between the engineer team (manufacture’s plant) and customer organizations (power plants), is proposed. Within report, the principle of parameterization expansion beyond the geometric constructions at the design and improvement process of steam turbine unit equipment is proposed, studied and justified. The report presents the steam turbine unit equipment design methodology based on the brand new oil-cooler design system that have been developed and implemented by authors. This design system combines the construction subsystem, which is characterized by extensive usage of family tables and templates, and computation subsystem, which includes a methodology for the thermal-hydraulic zone-by-zone oil coolers design calculations. The report presents data about the developed software for operational monitoring, assessment of equipment parameters features as well as its implementation on five power plants.

Habitability: from stars to cells

NASA Astrophysics Data System (ADS)

Javaux, Emmanuelle J.; Dehant, Véronique

2010-07-01

To determine where to search for life in our solar system or in other extrasolar systems, the concept of habitability has been developed, based on the only sample we have of a biological planet—the Earth. Habitability can be defined as the set of the necessary conditions for an active life to exist, even if it does not exist. In astronomy, a habitable zone (HZ) is the zone defined around a sun/star, where the temperature conditions allow liquid water to exist on its surface. This habitability concept can be considered from different scientific perspectives and on different spatial and time scales. Characterizing habitability at these various scales requires interdisciplinary research. In this article, we have chosen to develop the geophysical, geological, and biological aspects and to insist on the need to integrate them, with a particular focus on our neighboring planets, Mars and Venus. Important geodynamic processes may affect the habitability conditions of a planet. The dynamic processes, e.g., internal dynamo, magnetic field, atmosphere, plate tectonics, mantle convection, volcanism, thermo-tectonic evolution, meteorite impacts, and erosion, modify the planetary surface, the possibility to have liquid water, the thermal state, the energy budget, and the availability of nutrients. They thus play a role in the persistence of life on a planet. Earth had a liquid water ocean and some continental crust in the Hadean between 4.4 and 4.0 Ga (Ga: billions years ago), and may have been habitable very early on. The origin of life is not understood yet; but the oldest putative traces of life are early Archean (~3.5 Ga). Studies of early Earth habitats documented in the rock record hosting fossil life traces provide information about possible habitats suitable for life beyond Earth. The extreme values of environmental conditions in which life thrives today can also be used to characterize the “envelope” of the existence of life and the range of potential extraterrestrial habitats. The requirement of nutrients by life for biosynthesis of cellular constituents and for growth, reproduction, transport, and motility may suggest that a dynamic and rocky planet with hydrothermal activity and formation of relief, liquid water alteration, erosion, and runoff is required to replenish nutrients and to sustain life (as we know it). The concept of habitability is very Earth-centric, as we have only one biological planet to study. However, life elsewhere would most probably be based on organic chemistry and leave traces of its past or recent presence and metabolism by modifying microscopically or macroscopically the physico-chemical characteristics of its environment. The extent to which these modifications occur will determine our ability to detect them in astrobiological exploration. Looking at major steps in the evolution of life may help determining the probability of detecting life (as we know it) beyond Earth and the technology needed to detect its traces, be they morphological, chemical, isotopic, or spectral.

The State, Potential Distribution, and Biological Implications of Methane in the Martian Crust

NASA Technical Reports Server (NTRS)

Max, Michael D.; Clifford, Stephen M.

2000-01-01

The search for life on Mars has recently focused on its potential survival in deep (>2 km) subpermafrost aquifers where anaerobic bacteria, similar to those found in deep subsurface ecosystems on Earth, may have survived in an environment that has remained stable for billions of years. An anticipated by-product of this biological activity is methane. The detection of large deposits of methane gas and hydrate in the Martian cryosphere, or as emissions from deep fracture zones, would provide persuasive evidence of indigenous life and confirm the presence of a valuable in situ resource for use by future human explorers.

How rare is complex life in the Milky Way?

PubMed

Bounama, Christine; von Bloh, Werner; Franck, Siegfried

2007-10-01

An integrated Earth system model was applied to calculate the number of habitable Earth-analog planets that are likely to have developed primitive (unicellular) and complex (multicellular) life in extrasolar planetary systems. The model is based on the global carbon cycle mediated by life and driven by increasing stellar luminosity and plate tectonics. We assumed that the hypothetical primitive and complex life forms differed in their temperature limits and CO(2) tolerances. Though complex life would be more vulnerable to environmental stress, its presence would amplify weathering processes on a terrestrial planet. The model allowed us to calculate the average number of Earth-analog planets that may harbor such life by using the formation rate of Earth-like planets in the Milky Way as well as the size of a habitable zone that could support primitive and complex life forms. The number of planets predicted to bear complex life was found to be approximately 2 orders of magnitude lower than the number predicted for primitive life forms. Our model predicted a maximum abundance of such planets around 1.8 Ga ago and allowed us to calculate the average distance between potentially habitable planets in the Milky Way. If the model predictions are accurate, the future missions DARWIN (up to a probability of 65%) and TPF (up to 20%) are likely to detect at least one planet with a biosphere composed of complex life.

What makes a planet habitable, and how to search for habitable planets in other solar systems.

PubMed

Papagiannis, M D

1992-06-01

The availability of liquid water is the most important factor that makes a planet habitable, because water is a very effective polar molecule and hence an excellent solvent and facilitator for the complex chemistry of life. Its presence presupposes a planet with a significant mass that guarantees the presence of a substantial atmosphere, and a reasonable spinning rate to avoid overheating. It also implies that the planet is at moderate distances from its central star, a range that is called the Ecosphere or the Habitable Zone. Since the evolution of life to high intelligence seems to take billions of years, it requires also that the central star must be neither too massive, that will produce a lot of lethal UV radiation and will have too short a life-span to allow life to evolve, nor of very small mass which will be producing too feeble a radiation to sustain life. The detection of free Oxygen in the atmosphere of a planet is a very strong evidence for the presence of life, because Oxygen is highly reactive and would rapidly disappear by combining with other elements, unless it is continuously replenished by life as the by-product of the process of photosynthesis that builds food for life (sugars) from CO2 and H2O.

Quantitative Risk Assessment (QRA) for an Underground Blowout Scenario in the Gulf of Mexico (GoM) Well

NASA Astrophysics Data System (ADS)

Tyagi, M.; Zulqarnain, M.

2017-12-01

Offshore oil and gas exploration and production operations, involve the use of some of the cutting edge and challenging technologies of the modern time. These technological complex operations involves the risk of major accidents as well, which have been demonstrated by disasters such as the explosion and fire on the UK production platform piper alpha, the Canadian semi-submersible drilling rig Ocean Ranger and the explosion and capsizing of Deepwater horizon rig in the Gulf of Mexico. By conducting Quantitative Risk Assessment (QRA), safety of various operations as well as their associated risks and significance during the entire life phase of an offshore project can be quantitatively estimated. In an underground blowout, the uncontrolled formation fluids from higher pressure formation may charge up shallower overlying low pressure formations or may migrate to sea floor. Consequences of such underground blowouts range from no visible damage at the surface to the complete loss of well, loss of drilling rig, seafloor subsidence or hydrocarbons discharged to the environment. These blowouts might go unnoticed until the over pressured sands, which are the result of charging from higher pressure reservoir due to an underground blowout. Further, engineering formulas used to estimate the fault permeability and thickness are very simple in nature and may add to uncertainty in the estimated parameters. In this study the potential of a deepwater underground blowout are assessed during drilling life phase of a well in Popeye-Genesis field reservoir in the Gulf of Mexico to estimate the time taken to charge a shallower zone to its leak-off test (LOT) value. Parametric simulation results for selected field case show that for relatively high permeability (k = 40mD) fault connecting a deep over-pressured zone to a shallower low-pressure zone of similar reservoir volumes, the time to recharge the shallower zone up to its threshold LOT value is about 135 years. If the ratio of the reservoir volumes for shallower to deeper zone is about 0.1, the recharging time significantly decreased to 24 years. Also, the hydrocarbons might possibly migrate through casing-wellbore annulus due to delamination fractures between cement interfaces with rock/casing and any other micro annulus gap not isolated by cement.

Stream and riparian management for freshwater turtles.

PubMed

Bodie, J R

2001-08-01

The regulation and management of stream ecosystems worldwide have led to irreversible loss of wildlife species. Due to recent scrutiny of water policy and dam feasibility, there is an urgent need for fundamental research on the biotic integrity of streams and riparian zones. Although riverine turtles rely on stream and riparian zones to complete their life cycle, are vital producers and consumers, and are declining worldwide, they have received relatively little attention. I review the literature on the impacts of contemporary stream management on freshwater turtles. Specifically, I summarize and discuss 10 distinct practices that produce five potential biological repercussions. I then focus on the often-overlooked use of riparian zones by freshwater turtles, calculate a biologically determined riparian width, and offer recommendations for ecosystem management. Migration data were summarized on 10 species from eight US states and four countries. A riparian zone encompassing the majority of freshwater turtle migrations would need to span 150 m from the stream edge. Freshwater turtles primarily chose high, open sandy habitats to nest. Nests in North America contained eggs and hatchlings during April through September and often through the winter. In addition, freshwater turtles utilized diverse riparian habitats for feeding, nesting, and overwintering. Additional documentation of stream and riparian habitat use by turtles is needed.

Study on Fatigue Performance of Composite Bolted Joints with Bolt-Hole Delamination

NASA Astrophysics Data System (ADS)

Liu, M. J.; Yu, S.; Zhao, Q. Y.

2018-03-01

Fatigue performance of composite structure with imperfections is a challenging subject at present. Based on cohesive zone method and multi-continuum theory, delamination evolution response and fatigue life prediction of a 3D composite single-lap joint with a bolt-hole have been investigated through computer codes Abaqus and Fe-safe. Results from the comparison of a perfect composite bolted joint with another defect one indicates that a relatively small delamination damage around the bolt hole brings about significant degradation of local material performance. More notably, fatigue life of stress concentration region of composite bolted joints is highly sensitive to external loads, as an increase of 67% cyclic load amplitude leads to an decrease of 99.5% local fatigue life in this study. However, the numerical strategy for solving composite fatigue problems is meaningful to engineering works.

A Metagenomic Assembly-Based Approach to Decoding Taxa in the Dead Zone

NASA Astrophysics Data System (ADS)

Thrash, C.; Baker, B.; Seitz, K.; Gillies, L.; Temperton, B.; Rabalais, N. N.; Mason, O. U.

2016-02-01

Coastal regions of eutrophication-driven oxygen depletion are widespread and increasing in number. Also known as dead zones, these regions take their name from the deleterious effects of hypoxia (dissolved oxygen less than 2 mg/L) on shrimp, demersal fish, and other animal life. Dead zones result from nutrient enrichment of primary production, concomitant consumption by chemoorganotrophic aerobic microorganisms, and strong stratification that prevents ventilation of bottom water. One of the largest dead zones in the world occurs seasonally in the northern Gulf of Mexico (nGOM), where hypoxia can reach up to 22,000 square kilometers. To explore the underlying genomic variation and metabolic potential of microorganisms in hypoxia, we performed metagenomic and metatranscriptomic sequencing on six samples from the 2013 nGOM dead zone from both hypoxic and oxic bottom waters. Over 217 Mb of sequence was assembled into contigs of at least 3 kb with IDBA-UD, with 72 greater than 100 kb, and the largest 495 kb in length. Annotation by IMG recovered over 224 thousand genes in these contigs. Binning with tetra-ESOM and quality filtering based on relative coverage of sample-specific reads led to the recovery of 83 partial to near complete (31 over 70%) high-quality genomes. These metagenomes represent key microbial taxa previously determined to be numerically abundant from 16S rRNA data, such as Thaumarcheaota, Marine Group II Euryarchaeota, SAR406, Synechococcus spp., Actinobacteria, and Planctomycetes. Ongoing work includes the recruitment of metatranscriptomic data to binned contigs for evaluation of relative gene expression, metabolic reconstruction, and comparative genomics with related organisms elsewhere in the global oceans. These data will provide us with detailed information regarding the metabolic potential and activity of many of the key players in the nGOM dead zone.

Effect of the 5-HTTLPR polymorphism on posttraumatic stress disorder, depression, anxiety, and quality of life among Iraq and Afghanistan veterans.

PubMed

Kimbrel, Nathan A; Morissette, Sandra B; Meyer, Eric C; Chrestman, Roberta; Jamroz, Robert; Silvia, Paul J; Beckham, Jean C; Young, Keith A

2015-01-01

Posttraumatic stress disorder (PTSD), depression, anxiety, and stress are significant problems among returning veterans and are associated with reduced quality of life. A correlational design was used to examine the impact of a polymorphism (5-HTTLPR) in the serotonin transporter promoter gene on post-deployment adjustment among returning veterans. A total of 186 returning Iraq and Afghanistan veterans were genotyped for the 5-HTTLPR polymorphism. Symptoms of PTSD, depression, general stress, and anxiety were assessed along with quality of life. After controlling for combat exposure, age, sex of the participant, and race, 5-HTTLPR had a significant multivariate effect on post-deployment adjustment, such that S' carriers reported more post-deployment adjustment problems and worse quality of life than veterans homozygous for the L' allele. This effect was larger when the analyses were restricted to veterans of European ancestry. Our findings suggest that veterans who carry the S' allele of the 5-HTTLPR polymorphism may be at increased risk for adjustment problems and reduced quality of life following deployments to war zones.

Determinants of Transitional Zone Area and Porosity of the Proximal Femur Quantified In Vivo in Postmenopausal Women.

PubMed

Shigdel, Rajesh; Osima, Marit; Lukic, Marko; Ahmed, Luai A; Joakimsen, Ragnar M; Eriksen, Erik F; Bjørnerem, Åshild

2016-04-01

Bone architecture as well as size and shape is important for bone strength and risk of fracture. Most bone loss is cortical and occurs by trabecularization of the inner part of the cortex. We therefore wanted to identify determinants of the bone architecture, especially the area and porosity of the transitional zone, an inner cortical region with a large surface/matrix volume available for intracortical remodeling. In 211 postmenopausal women aged 54 to 94 years with nonvertebral fractures and 232 controls from the Tromsø Study, Norway, we quantified femoral subtrochanteric architecture in CT images using StrAx1.0 software, and serum levels of bone turnover markers (BTM, procollagen type I N-terminal propeptide and C-terminal cross-linking telopeptide of type I collagen). Multivariable linear and logistic regression analyses were used to quantify associations of age, weight, height, and bone size with bone architecture and BTM, and odds ratio (OR) for fracture. Increasing age, height, and larger total cross-sectional area (TCSA) were associated with larger transitional zone CSA and transitional zone CSA/TCSA (standardized coefficients [STB] = 0.11 to 0.80, p ≤ 0.05). Increasing weight was associated with larger TCSA, but smaller transitional zone CSA/TCSA and thicker cortices (STB = 0.15 to 0.22, p < 0.01). Increasing height and TCSA were associated with higher porosity of the transitional zone (STB = 0.12 to 0.46, p < 0.05). Increasing BTM were associated with larger TCSA, larger transitional zone CSA/TCSA, and higher porosity of each of the cortical compartments (p < 0.01). Fracture cases exhibited larger transitional zone CSA and higher porosity than controls (p < 0.001). Per SD increasing CSA and porosity of the transitional zone, OR for fracture was 1.71 (95% CI, 1.37 to 2.14) and 1.51 (95% CI, 1.23 to 1.85), respectively. Cortical bone architecture is determined mainly by bone size as built during growth and is modified by lifestyle factors throughout life through bone turnover. Fracture cases exhibited larger transitional zone area and porosity, highlighting the importance of cortical bone architecture for fracture propensity. © 2015 American Society for Bone and Mineral Research.

Research on climate impacts to forests began early at Fort Valley Experimental Forest

Treesearch

Brian W. Geils; Susan D. Olberding

2012-01-01

Even before Arizona was a state, government scientists walked and rode across its broad, open landscapes from nearly sea level to over 12,000 feet of elevation, observing its diverse vegetation and climate. In 1889, biologist C. Hart Merriam traversed northern Arizona and found six of the seven world life zones he would later describe by latitude and elevation. The...

Chemical and physical analyses of selected plants and soils from Puerto Rico (1981-2000)

Treesearch

M.J. Sanchez; E. Lopez; A.E. Lugo

2015-01-01

This report contains the results of analyses conducted at the chemistry laboratory of the International Institute of Tropical Forestry in Puerto Rico from 1981 to 2000. The data set includes 109,177 plant analyses and 70,729 soil analyses. We report vegetation chemical data by plant part, species, life zone, soil order, geology, or parent material. Soil data are...

78 FR 42902 - Safety Zone; Olympus Tension Leg Platform, Mississippi Canyon Block 807, Outer Continental Shelf...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-18

..., an email address, or a telephone number in the body of your document so that we can contact you if we... Federal Register (73 FR 3316). 4. Public Meeting We do not now plan to hold a public meeting. But you may... the purpose of protecting life, property and the marine environment (33 CFR 147.1). Placing a safety...

The lugworm Arenicola marina: A model of physiological adaptation to life in intertidal sediments

NASA Astrophysics Data System (ADS)

Zebe, E.; Schiedek, D.

1996-03-01

The results of more than two decades of intensive research on the physiological and biochemical features of the lugworm are reviewed with the aim of drawing a general and comprehensive picture of the adaptation of this species to the special conditions of living in the tidal zone, which may also hold true for the majority of invertebrates found in this habitat.

77 FR 38497 - Safety Zone; Richmond-Essex County Fourth of July Fireworks, Rappahannock River, Tappahannock, VA

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-28

... AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard will establish a...-Essex County Fourth of July Fireworks event. This action is necessary to provide for the safety of life... displays. DATES: This rule will be effective from 9 p.m. on June 30, 2012, until 10 p.m. on July 1, 2012...

Black Suburbanization: Access to Improved Quality of Life or Maintenance of the Status Quo?

ERIC Educational Resources Information Center

Rose, Harold M.

Large numbers of blacks have been moving into residential zones outside the central city but within what is sometimes called the metropolitan ring. By 1970, 3.5 million blacks, or a million more than in 1960, lived in these areas. Although these areas are outside the city proper, they should not be linked to the images held of typical suburbia.…

Life history of abyssal and hadal fishes from otolith growth zones and oxygen isotopic compositions

NASA Astrophysics Data System (ADS)

Gerringer, M. E.; Andrews, A. H.; Huss, G. R.; Nagashima, K.; Popp, B. N.; Linley, T. D.; Gallo, N. D.; Clark, M. R.; Jamieson, A. J.; Drazen, J. C.

2018-02-01

Hadal trenches are isolated habitats that cover the greatest ocean depths (6,500-11,000 m) and are believed to host high levels of endemism across multiple taxa. A group of apparent hadal endemics is within the snailfishes (Liparidae), found in at least five geographically separated trenches. Little is known about their biology, let alone the reasons for their success at hadal depths around the world. This study investigated the life history of hadal liparids using sagittal otoliths of two species from the Kermadec (Notoliparis kermadecensis) and Mariana (Pseudoliparis swirei) trenches in comparison to successful abyssal macrourids found at the abyssal-hadal transition zone. Otoliths for each species revealed alternating opaque and translucent growth zones that could be quantified in medial sections. Assuming these annuli represent annual growth, ages were estimated for the two hadal liparid species to be from five to 16 years old. These estimates were compared to the shallower-living snailfish Careproctus melanurus, which were older than described in previous studies, expanding the potential maximum age for the liparid family to near 25 years. Age estimates for abyssal macrourids ranged from eight to 29 years for Coryphaenoides armatus and six to 16 years for C. yaquinae. In addition, 18O/16O ratios (δ18O) were measured across the otolith using secondary ion mass spectrometry (SIMS) to investigate the thermal history of the three liparids, and two macrourids. Changes in δ18O values were observed across the otoliths of C. melanurus, C. armatus, and both hadal liparids, the latter of which may represent a change of >5 °C in habitat temperature through ontogeny. The results would indicate there is a pelagic larval stage for the hadal liparids that rises to a depth above 1000 m, followed by a return to the hadal environment as these liparids grow. This result was unexpected for the hadal liparids given their isolated environment and large eggs, and the biological implications and plausibility of interpretations of these data are discussed. This study presents a first look at the life history of some of the deepest-living fishes through otolith analyses.

Modeling the influence of coupled mass transfer processes on mass flux downgradient of heterogeneous DNAPL source zones

NASA Astrophysics Data System (ADS)

Yang, Lurong; Wang, Xinyu; Mendoza-Sanchez, Itza; Abriola, Linda M.

2018-04-01

Sequestered mass in low permeability zones has been increasingly recognized as an important source of organic chemical contamination that acts to sustain downgradient plume concentrations above regulated levels. However, few modeling studies have investigated the influence of this sequestered mass and associated (coupled) mass transfer processes on plume persistence in complex dense nonaqueous phase liquid (DNAPL) source zones. This paper employs a multiphase flow and transport simulator (a modified version of the modular transport simulator MT3DMS) to explore the two- and three-dimensional evolution of source zone mass distribution and near-source plume persistence for two ensembles of highly heterogeneous DNAPL source zone realizations. Simulations reveal the strong influence of subsurface heterogeneity on the complexity of DNAPL and sequestered (immobile/sorbed) mass distribution. Small zones of entrapped DNAPL are shown to serve as a persistent source of low concentration plumes, difficult to distinguish from other (sorbed and immobile dissolved) sequestered mass sources. Results suggest that the presence of DNAPL tends to control plume longevity in the near-source area; for the examined scenarios, a substantial fraction (43.3-99.2%) of plume life was sustained by DNAPL dissolution processes. The presence of sorptive media and the extent of sorption non-ideality are shown to greatly affect predictions of near-source plume persistence following DNAPL depletion, with plume persistence varying one to two orders of magnitude with the selected sorption model. Results demonstrate the importance of sorption-controlled back diffusion from low permeability zones and reveal the importance of selecting the appropriate sorption model for accurate prediction of plume longevity. Large discrepancies for both DNAPL depletion time and plume longevity were observed between 2-D and 3-D model simulations. Differences between 2- and 3-D predictions increased in the presence of sorption, especially for the case of non-ideal sorption, demonstrating the limitations of employing 2-D predictions for field-scale modeling.

Cytonuclear genetics of experimental fish hybrid zones inside Biosphere 2

USGS Publications Warehouse

Scribner, K.T.; Avise, John C.

1994-01-01

Two species of mosquitofish (family Poeciliidae) known to hybridize in nature were introduced into freshwater habitats inside Biosphere 2, and their population genetics were monitored after 2 years. Within four to six generations, nuclear and cytoplasmic markers characteristic of Gambusia holbrooki had risen greatly in frequency, although some Gambusia affinis alleles and haplotypes were retained primarily in recombinant genotypes, indicative of introgressive hybridization. The temporal cytonuclear dynamics proved similar to population genetic changes observed in replicated experimental hybrid populations outside of Biosphere 2, thus indicating strong directional selection favoring G. holbrooki genotypes across the range of environments monitored. When interpreted in the context of species-specific population demographies observed previously, results suggest that the extremely rapid evolution in these zones of secondary contact is attributable primarily to species differences in life-history traits.

Study to determine the aquatic biological effects on the Solid Rocket Booster (SRB). [technique for monitoring marine microbial fouling

NASA Technical Reports Server (NTRS)

Colwell, R. R.; Zachary, A.

1979-01-01

The surface of the reusable solid rocket boosters (SRB), which are jettisoned from the Shuttle Orbiter to parachute in the sea, are studied for colonization by marine life. Techniques for monitoring the marine microbial fouling of SRB materials are presented. An assessment of the nature and degree of the biofouling expected on the SRB materials in the recovery zone is reported. A determination of the degree and the effects of seasonal variation occurring on microbial fouling in the retrieval zone waters is made. The susceptibility of the SRB parachute recovery system to microbial fouling and biodeterioration is investigated. The development of scanning electron microscopy and epifluorescence microscopic observation techniques for rapid assessment of microbial fouling is discussed.

Concise review: Pax6 transcription factor contributes to both embryonic and adult neurogenesis as a multifunctional regulator.

PubMed

Osumi, Noriko; Shinohara, Hiroshi; Numayama-Tsuruta, Keiko; Maekawa, Motoko

2008-07-01

Pax6 is a highly conserved transcription factor among vertebrates and is important in various developmental processes in the central nervous system (CNS), including patterning of the neural tube, migration of neurons, and formation of neural circuits. In this review, we focus on the role of Pax6 in embryonic and postnatal neurogenesis, namely, production of new neurons from neural stem/progenitor cells, because Pax6 is intensely expressed in these cells from the initial stage of CNS development and in neurogenic niches (the subgranular zone of the hippocampal dentate gyrus and the subventricular zone of the lateral ventricle) throughout life. Pax6 is a multifunctional player regulating proliferation and differentiation through the control of expression of different downstream molecules in a highly context-dependent manner.

Moral injury: a mechanism for war-related psychological trauma in military family members.

PubMed

Nash, William P; Litz, Brett T

2013-12-01

Recent research has provided compelling evidence of mental health problems in military spouses and children, including post-traumatic stress disorder (PTSD), related to the war-zone deployments, combat exposures, and post-deployment mental health symptoms experienced by military service members in the family. One obstacle to further research and federal programs targeting the psychological health of military family members has been the lack of a clear, compelling, and testable model to explain how war-zone events can result in psychological trauma in military spouses and children. In this article, we propose a possible mechanism for deployment-related psychological trauma in military spouses and children based on the concept of moral injury, a model that has been developed to better understand how service members and veterans may develop PTSD and other serious mental and behavioral problems in the wake of war-zone events that inflict damage to moral belief systems rather by threatening personal life and safety. After describing means of adapting the moral injury model to family systems, we discuss the clinical implications of moral injury, and describe a model for its psychological treatment.

Environmental geochemical study of Red Mountain--an undisturbed volcanogenic massive sulfide deposit in the Bonnifield District, Alaska range, east-central Alaska: Chapter I in Recent U.S. Geological Survey studies in the Tintina Gold Province, Alaska, United States, and Yukon, Canada--results of a 5-year project

USGS Publications Warehouse

Eppinger, Robert G.; Briggs, Paul H.; Dusel-Bacon, Cynthia; Giles, Stuart A.; Gough, Larry P.; Hammarstrom, Jane M.; Hubbard, Bernard E.

2007-01-01

Water samples with the lowest pH values, highest specific conductances, and highest major- and trace-element concentrations are from springs and streams within the quartz-sericite-pyrite alteration zone. Aluminum, As, Cd, Co, Cu, Fe, Mn, Ni, Pb, Y, and particularly Zn and the REEs are all found in high concentrations, ranging across four orders of magnitude. Waters collected upstream from the alteration zone have near-neutral pH values, lower specific conductances, lower metal concentrations, and measurable alkalinities. Water samples collected downstream of the alteration zone have pH values and metal concentrations intermediate between these two extremes. Stream sediments are anomalous in Zn, Pb, S, Fe, Cu, As, Co, Sb, and Cd relative to local and regional background abundances. Red Mountain Creek and its tributaries do not support, and probably never have supported, significant megascopic faunal aquatic life.

Beyond the principle of plentitude: a review of terrestrial planet habitability.

PubMed

Gaidos, E; Deschenes, B; Dundon, L; Fagan, K; Menviel-Hessler, L; Moskovitz, N; Workman, M

2005-04-01

We review recent work that directly or indirectly addresses the habitability of terrestrial (rocky) planets like the Earth. Habitability has been traditionally defined in terms of an orbital semimajor axis within a range known as the habitable zone, but it is also well known that the habitability of Earth is due to many other astrophysical, geological, and geochemical factors. We focus this review on (1) recent refinements to habitable zone calculations; (2) the formation and orbital stability of terrestrial planets; (3) the tempo and mode of geologic activity (e.g., plate tectonics) on terrestrial planets; (4) the delivery of water to terrestrial planets in the habitable zone; and (5) the acquisition and loss of terrestrial planet carbon and nitrogen, elements that constitute important atmospheric gases responsible for habitable conditions on Earth's surface as well as being the building blocks of the biosphere itself. Finally, we consider recent work on evidence for the earliest habitable environments and the appearance of life itself on our planet. Such evidence provides us with an important, if nominal, calibration point for our search for other habitable worlds.

Recent 121-year variability of western boundary upwelling in the northern South China Sea

NASA Astrophysics Data System (ADS)

Liu, Yi; Peng, Zicheng; Shen, Chuan-Chou; Zhou, Renjun; Song, Shaohua; Shi, Zhengguo; Chen, Tegu; Wei, Gangjian; Delong, Kristine L.

2013-06-01

upwelling is typically related to the eastern boundary upwelling system, whereas the powerful southwest Asian summer monsoon can also generate significant cold, nutrient-rich deep water in western coastal zones. Here we present a sea surface temperature record (A.D. 1876-1996) derived from coral Porites Sr/Ca for an upwelling zone in the northern South China Sea. The upwelling-induced sea surface temperature anomaly record reveals prominent multidecadal variability driven by Asian summer monsoon dynamics with an abrupt transition from warmer to colder conditions in 1930, and a return to warmer conditions after 1960. Previous studies suggest the expected increase in atmospheric CO2 for the coming decades may result in intensification in the eastern boundary upwelling system, which could enhance upwelling of CO2-rich deep water thus exacerbating the impact of acidification in these productive zones. In contrast, the weakening trend since 1961 in the upwelling time series from the northern South China Sea suggests moderate regional ocean acidification from upwelling thus a stress relief for marine life in this region.

The Preston of the Guinier-Preston Zones. Guinier

NASA Astrophysics Data System (ADS)

Hardouin Duparc, O. B. M.

2010-10-01

Almost all materials scientists know about the Guinier-Preston (GP) zones, which were discovered in age-hardened aluminum-copper alloys in 1938. One of the discoverers, the French André Guinier, is rightly well known. The other discoverer, the British G.D. Preston, is totally ignored, even in English scientific biographies. I wish here to partly make up for this “oblivion” by giving elements about George Preston’s life (August 8, 1896 to June 22, 1972) and scientific work. Born in Ireland to the physicist Thomas Preston and deceased in Scotland, G. Preston carried out his scientific achievements in England, mainly studying the crystallographic structure of metals, metallic alloys, and thin films of metal oxides in a pioneering way. He also discussed the atomistic structure of twins in 1927. He mastered many kinds of X-ray and electron diffraction techniques up to diffuse scattering, which allowed him to detect the GP zones. Although he was involved in several controversies, including one about diamonds, he always remained a forthright person until his final professorship in Dundee. André Guinier’s career is briefly recalled in a parallel way.

The Preston of the Guinier-Preston Zones. Guinier

NASA Astrophysics Data System (ADS)

Hardouin Duparc, O. B. M.

2010-08-01

Almost all materials scientists know about the Guinier-Preston (GP) zones, which were discovered in age-hardened aluminum-copper alloys in 1938. One of the discoverers, the French André Guinier, is rightly well known. The other discoverer, the British G.D. Preston, is totally ignored, even in English scientific biographies. I wish here to partly make up for this “oblivion” by giving elements about George Preston’s life (August 8, 1896 to June 22, 1972) and scientific work. Born in Ireland to the physicist Thomas Preston and deceased in Scotland, G. Preston carried out his scientific achievements in England, mainly studying the crystallographic structure of metals, metallic alloys, and thin films of metal oxides in a pioneering way. He also discussed the atomistic structure of twins in 1927. He mastered many kinds of X-ray and electron diffraction techniques up to diffuse scattering, which allowed him to detect the GP zones. Although he was involved in several controversies, including one about diamonds, he always remained a forthright person until his final professorship in Dundee. André Guinier’s career is briefly recalled in a parallel way.

Isothermal fatigue mechanisms in Ti-based metal matrix composites

NASA Technical Reports Server (NTRS)

Majumdar, Bhaskar S.; Newaz, Golam M.

1993-01-01

Stress-controlled isothermal fatigue experiments were performed at room temperature (RT) and 548 C (in argon) on (0)8 SCS6/Ti 15-3 metal matrix composites (MMC's) with 15 and 41 volume percent SCS6 (SiC) fibers. The primary objectives were to evaluate the mechanical responses, and to obtain a clear understanding of the damage mechanisms leading to failure of the MMC's. The mechanical data indicated that strain ranges attained fairly constant values in the stress-controlled experiments at both RT and 538 C, and remained so for more than 85 percent of life. The fatigue data for MMC's with different volume fraction fibers showed that MMC life was controlled by the imposed strain range rather than the stress range. At RT, and at low and intermediate strain ranges, the dominant fatigue mechanism was matrix fatigue, and this was confirmed metallurgically from fractographic evidence as well as from observations of channel type dislocation structures in the matrix of fatigued MMC specimens. Reaction-zone cracks acted as important crack initiating sites at RT, with their role being to facilitate slip band formation and consequent matrix crack initiation through classical fatigue mechanisms. MMC life agreed with matrix life at the lower strain ranges, but was smaller than matrix life at higher strain ranges. Unlike the case of monotonic deformation, debonding damage was another major damage mechanism during fatigue at RT, and it increased for higher strain ranges. At high strain ranges at RT, fractography and metallography showed an absence of matrix cracks, but long lengths of debonds in the outer layers of the SCS6 fibers. Such debonding and consequent rubbing during fatigue is believed to have caused fiber damage and their failure at high strain ranges. Thus, whereas life was matrix dominated at low and intermediate strain ranges, it was fiber dominated at high strain ranges. At 538 C, the mean stain constantly increased (ratchetting) with the number of cycles. At high strain ranges, such ratchetting led to overload failure of the fibers, and debonding of the type at RT was very small. At intermediate strain ranges, fractography showed large areas of matrix cracks. However, in spite of this matrix dominated mechanism, the MMC life at elevated temperatures was significantly less than the matrix fatigue life at all strain ranges. The reason for this difference is still unclear, although metallographic and fractographic evidences suggest that internal crack initiation sites at Mo-ribbons and reaction-zone cracks may have played a critical role, with the former tending to dominate.

Exoplanets: the quest for Earth twins.

PubMed

Mayor, Michel; Udry, Stephane; Pepe, Francesco; Lovis, Christophe

2011-02-13

Today, more than 400 extra-solar planets have been discovered. They provide strong constraints on the structure and formation mechanisms of planetary systems. Despite this huge amount of data, we still have little information concerning the constraints for extra-terrestrial life, i.e. the frequency of Earth twins in the habitable zone and the distribution of their orbital eccentricities. On the other hand, these latter questions strongly excite general interest and trigger future searches for life in the Universe. The status of the extra-solar planets field--in particular with respect to very-low-mass planets--will be discussed and an outlook on the search for Earth twins will be given in this paper.

Zur Biologie des marinen Heterotardigraden Tetrakentron synaptae

NASA Astrophysics Data System (ADS)

Kristensen, R. M.

1980-06-01

The life cycle of Tetrakentron synaptae Cuénot, 1892, a tardigrade closely associated with the sea cucumber Leptosynapta galliennei Herapath, was investigated in the littoral zone at Roscoff (France). Eggs and juveniles were found only in June and July, adults only from May to October. There are vagile males and stationary dwarf males. The dorsoventrally flattened body, an enlarged slimy epicuticle in females and dwarf males, the full set of claws also in juveniles, and the anus, which is in a dorsocaudal position, are indicative for an epizoic, sessile life. There is strong evidence that T. synaptae punctures the cells of L. galliennei and sucks out their content, which is indicative of parasitism.

Prevalence and distribution of odontogenic cysts in a Mexican sample. A 753 cases study.

PubMed

Villasis-Sarmiento, Luis; Portilla-Robertson, Javier; Melendez-Ocampo, Arcelia; Gaitan-Cepeda, Luis-Alberto; Leyva-Huerta, Elba-Rosa

2017-04-01

Odontogenic cysts (OC) are the most frequent lesions of the jaws and their constant epidemiological update is necessary and indispensable. Therefore the principal objective of this report was To determine prevalence and clinical-demographical characteristics of OC in a Mexican sample. 753 cases of OC coming from the archive of a head and neck histopathological teaching service, from January 2000 to December 2013, were included. OC cases were re-assessed according 2005 WHO classification. Chi square test was used to establish possible associations ( p <0.05IC95%). From 753 OC, 369 were female and 384 male; 52.9% of them were in their 2nd- 4th decade of life. The most common location (41%) was the mandibular posterior area. Radicular cysts were more frequent in maxillary anterior zone of females ( p 0.0002) at their fourth decade of life. Dentigerous cysts were more frequent in the mandibular posterior zone of males ( p 0.0000) in their second decade of life. Six cases of periodontal lateral cyst; 4 cases of paradental cysts; 4 eruption cysts and 4 cases of adult gingival cyst, as well were identified. Radicular cyst and dentigerous cyst are the most prevalent odontogenic cyst in this Mexican sample. Due to their etiology, dental pulpar necrosis and impacted teeth, radicular cyst and dentigerous cyst could be prevenible. Therefore, it is necessary to establish preventive strategies to diminish dental decay and programs of prophylactic extractions of impacted teeth, to in consequence decrease the prevalence of odontogenic cysts. Key words: Cyst, dentigerous cyst, mexican, odontogenic cyst, radicular cyst.

Limit Cycles Can Reduce the Width of the Habitable Zone

NASA Astrophysics Data System (ADS)

Haqq-Misra, Jacob; Kopparapu, Ravi Kumar; Batalha, Natasha E.; Harman, Chester E.; Kasting, James F.

2016-08-01

The liquid water habitable zone (HZ) describes the orbital distance at which a terrestrial planet can maintain above-freezing conditions through regulation by the carbonate-silicate cycle. Recent calculations have suggested that planets in the outer regions of the HZ cannot maintain stable, warm climates, but rather should oscillate between long, globally glaciated states and shorter periods of climatic warmth. Such conditions, similar to “Snowball Earth” episodes experienced on Earth, would be inimical to the development of complex land life, including intelligent life. Here, we build on previous studies with an updated energy balance climate model to calculate this “limit cycle” region of the HZ where such cycling would occur. We argue that an abiotic Earth would have a greater CO2 partial pressure than today because plants and other biota help to enhance the storage of CO2 in soil. When we tune our abiotic model accordingly, we find that limit cycles can occur but that previous calculations have overestimated their importance. For G stars like the Sun, limit cycles occur only for planets with CO2 outgassing rates less than that on modern Earth. For K- and M-star planets, limit cycles should not occur; however, M-star planets may be inhospitable to life for other reasons. Planets orbiting late G-type and early K-type stars retain the greatest potential for maintaining warm, stable conditions. Our results suggest that host star type, planetary volcanic activity, and seafloor weathering are all important factors in determining whether planets will be prone to limit cycling.

Creep Strength Behavior of Boron Added P91 Steel and its Weld in the Temperature Range of 600-650°C

NASA Astrophysics Data System (ADS)

Swaminathan, J.; Das, C. R.; Baral, Jayashree; Phaniraj, C.; Ghosh, R. N.; Albert, S. K.; Bhaduri, A. K.

One of the promising ways for mitigation of Type IV cracking — a failure by cracking at the intercritical /fine grained heat affected zone, a life limiting problem in advanced 9-12 Cr ferritic steel weld like that of P91 is through modification of alloy composition by addition of boron. Addition of boron was observed to improve the microstructure at the weld zone and hence the creep strength. In the present work, boron (100 ppm with controlled nitrogen) added P91 steel after normalizing at 1050°C and 1150°C and tempered at 760°C were studied for the creep behavior in the base metal and welded condition in the temperature range of 600-650°C. Creep strength was characterized in terms of stress and temperature dependence of creep rate and rupture time. Weld creep life was reduced compared to the base metal with rupture occurring at the ICHAZ (Type IV crack). However at longer time (at lower stress levels) exposure creep crack moves from weld metal to HAZ (Type II crack). Rupture life was found to superior for the base and weld in the boron containing steel when higher normalizing temperature is used. Estimation of 105 h was attempted based on short term rupture data available and weld strength factors were calculated. Observed values are better for P91BH condition than the values for P91BLcondition as well as those available for P91 in open literature

PLANET TOPERS: Planets, Tracing the Transfer, Origin, Preservation, and Evolution of their ReservoirS

NASA Astrophysics Data System (ADS)

Dehant, Veronique; Breuer, Doris; Claeys, Philippe; Debaille, Vinciane; De Keyser, Johan; Javaux, Emmanuelle; Goderis, Steven; Karatekin, Ozgur; Mattielli, Nadine; Noack, Lena; Spohn, Tilman; Carine Vandaele, Ann; Vanhaecke, Frank; Van Hoolst, Tim; Wilquet, Valerie

2013-04-01

The PLANET TOPERS (Planets, Tracing the Transfer, Origin, Preservation, and Evolution of their ReservoirS) group is an Inter-university attraction pole (IAP) addressing the question of habitability in our Solar System. Habitability is commonly understood as "the potential of an environment (past or present) to support life of any kind" (Steele et al., 2005, http://mepag.jpl.nasa.gov/reports/archive.html). Based on the only known example of Earth, the concept refers to whether environmental conditions are available that could eventually support life, even if life does not currently exist (Javaux and Dehant, 2010, Astron. Astrophys. Rev., 18, 383-416, DOI: 10.1007/s00159-010-0030-4). Life includes properties such as consuming nutrients and producing waste, the ability to reproduce and grow, pass on genetic information, evolve, and adapt to the varying conditions on a planet (Sagan, 1970, Encyclopedia Britannica, 22, 964-981). Terrestrial life requires liquid water. The stability of liquid water at the surface of a planet defines a habitable zone (HZ) around a star. In the Solar System, it stretches between Venus and Mars, but excludes these two planets. If the greenhouse effect is taken into account, the habitable zone may have included early Mars while the case for Venus is still debated. Important geodynamic processes affect the habitability conditions of a planet. As envisaged by the group, this IAP develops and closely integrates the geophysical, geological, and biological aspects of habitability with a particular focus on Earth neighboring planets, Mars and Venus. It works in an interdisciplinary approach to understand habitability and in close collaboration with another group, the Helmholtz Alliance "Life and Planet Evolution", which has similar objectives. The dynamic processes, e.g. internal dynamo, magnetic field, atmosphere, plate tectonics, mantle convection, volcanism, thermo-tectonic evolution, meteorite impacts, and erosion, modify the planetary surface, the possibility to have liquid water, the thermal state, the energy budget and the availability of nutrients. Shortly after formation (Hadean 4.4-4.0 Ga (billion years)), evidence supports the presence of a liquid ocean and continental crust on Earth (Wilde et al., 2001, Nature, 409, 175-178), Earth may thus have been habitable very early on. The origin of life is not understood yet but the oldest putative traces of life occur in the early Archaean (~3.5 Ga). Studies of early Earth habitats documented in rock containing traces of fossil life provide information about environmental conditions suitable for life beyond Earth, as well as methodologies for their identification and analyses. The extreme values of environmental conditions in which life thrives today can also be used to characterize the "envelope" of the existence of life and the range of potential extraterrestrial habitats. The requirement of nutrients for biosynthesis, growth, and reproduction suggest that a tectonically active planet, with liquid water is required to replenish nutrients and sustain life (as currently known). These dynamic processes play a key role in the apparition and persistence of life. This contribution will focus on the highlights of the work of the IAP Planet TOPERS.

Genomic potential hypothesis of evolution: a concept of biogenesis in habitable spaces of the universe.

PubMed

Schwabe, Christian

2002-11-01

The new hypothesis of evolution establishes a contiguity of life sciences with cosmology, physics, and chemistry, and provides a basis for the search for life on other planets. Chemistry is the sole driving force of the assembly of life, under the subtle guidance exerted by bonding orbital geometry. That phenomenon leads to multiple origins that function on the same principles but are different to the extent that their nucleic acid core varies. Thus, thoughts about the origins of life and the development of complexity have been transferred from the chance orientation of the past to the realm of atomic structures, which are subject to the laws of thermodynamics and kinetics. Evolution is a legitimate subject of basic science, and the complexity of life will submit to the laws of chemistry and physics as the problem is viewed from a new perspective. The paradigm connects life to the big events that formed every sphere of our living space and that keeps conditions fine-tuned for life to persist, perhaps a billion years or more. The "genomic potential" hypothesis leads to the prediction that life like ours is likely to exist in galaxies that are as distant from the origin of the universe as the Milky Way, and that the habitable zone of our galaxy harbors other living planets as well. Copyright 2002 Wiley-Liss, Inc.

Interdisciplinary rural immersion week.

PubMed

Deutchman, Mark E; Nearing, Kathryn; Baumgarten, Brenda; Westfall, John M

2012-01-01

Health professions students interested in future rural practice locations spend a week learning about and investigating all aspects of small town personal, professional and community life. This augments the mainly clinical experience provided by clinical rotations they complete as part of their professional academic training program. Students from professional programs in medicine, physician assistant, pharmacy, nursing, public health and psychology travel to a small community, receive an orientation and in small interprofessional groups investigate health care, education, government, law enforcement, public health, economy and natural resources. Participants report that the experience raises their interest in future rural practice, answers questions they have about rural life and enhances their understanding of the issues they must learn more about before making a career location choice. The interdisciplinary rural immersion program provides students with the time, structure and permission to move out of their clinical 'comfort zone' and think about the cultural, economic and environmental aspects of rural life and work.

Barrier to gene flow between two ecologically divergent Populus species, P. alba (white poplar) and P. tremula (European aspen): the role of ecology and life history in gene introgression.

PubMed

Lexer, C; Fay, M F; Joseph, J A; Nica, M-S; Heinze, B

2005-04-01

The renewed interest in the use of hybrid zones for studying speciation calls for the identification and study of hybrid zones across a wide range of organisms, especially in long-lived taxa for which it is often difficult to generate interpopulation variation through controlled crosses. Here, we report on the extent and direction of introgression between two members of the "model tree" genus Populus: Populus alba (white poplar) and Populus tremula (European aspen), across a large zone of sympatry located in the Danube valley. We genotyped 93 hybrid morphotypes and samples from four parental reference populations from within and outside the zone of sympatry for a genome-wide set of 20 nuclear microsatellites and eight plastid DNA restriction site polymorphisms. Our results indicate that introgression occurs preferentially from P. tremula to P. alba via P. tremula pollen. This unidirectional pattern is facilitated by high levels of pollen vs. seed dispersal in P. tremula (pollen/seed flow = 23.9) and by great ecological opportunity in the lowland floodplain forest in proximity to P. alba seed parents, which maintains gene flow in the direction of P. alba despite smaller effective population sizes (N(e)) in this species (P. alba N(e)c. 500-550; P. tremula N(e)c. 550-700). Our results indicate that hybrid zones will be valuable tools for studying the genetic architecture of the barrier to gene flow between these two ecologically divergent Populus species.

Groundwater table fluctuations recorded in zonation of microbial siderites from end-Triassic strata

NASA Astrophysics Data System (ADS)

Weibel, R.; Lindström, S.; Pedersen, G. K.; Johansson, L.; Dybkjær, K.; Whitehouse, M. J.; Boyce, A. J.; Leng, M. J.

2016-08-01

In a terrestrial Triassic-Jurassic boundary succession of southern Sweden, perfectly zoned sphaerosiderites are restricted to a specific sandy interval deposited during the end-Triassic event. Underlying and overlying this sand interval there are several other types of siderite micromorphologies, i.e. poorly zoned sphaerosiderite, spheroidal (ellipsoid) siderite, spherical siderite and rhombohedral siderite. Siderite overgrowths occur mainly as rhombohedral crystals on perfectly zoned sphaerosiderite and as radiating fibrous crystals on spheroidal siderite. Concretionary sparry, microspar and/or micritic siderite cement postdate all of these micromorphologies. The carbon isotope composition of the siderite measured by conventional mass spectrometry shows the characteristic broad span of data, probably as a result of multiple stages of microbial activity. SIMS (secondary ion mass spectrometry) revealed generally higher δ13C values for the concretionary cement than the perfectly zoned sphaerosiderite, spheroidal siderite and their overgrowths, which marks a change in the carbon source during burial. All the various siderite morphologies have almost identical oxygen isotope values reflecting the palaeo-groundwater composition. A pedogenic/freshwater origin is supported by the trace element compositions of varying Fe:Mn ratios and low Mg contents. Fluctuating groundwater is the most likely explanation for uniform repeated siderite zones of varying Fe:Mn ratios reflecting alternating physiochemical conditions and hostility to microbial life/activity. Bacterially mediated siderite precipitation likely incorporated Mn and other metal ions during conditions that are not favourable for the bacteria and continued with Fe-rich siderite precipitation as the physico-chemical conditions changed into optimal conditions again, reflecting the response to groundwater fluctuations.

Assessing Urban Streets Network Vulnerability against Earthquake Using GIS - Case Study: 6TH Zone of Tehran

NASA Astrophysics Data System (ADS)

Rastegar, A.

2017-09-01

Great earthquakes cause huge damages to human life. Street networks vulnerability makes the rescue operation to encounter serious difficulties especially at the first 72 hours after the incident. Today, physical expansion and high density of great cities, due to narrow access roads, large distance from medical care centers and location at areas with high seismic risk, will lead to a perilous and unpredictable situation in case of the earthquake. Zone # 6 of Tehran, with 229,980 population (3.6% of city population) and 20 km2 area (3.2% of city area), is one of the main municipal zones of Tehran (Iran center of statistics, 2006). Major land-uses, like ministries, embassies, universities, general hospitals and medical centers, big financial firms and so on, manifest the high importance of this region on local and national scale. In this paper, by employing indexes such as access to medical centers, street inclusion, building and population density, land-use, PGA and building quality, vulnerability degree of street networks in zone #6 against the earthquake is calculated through overlaying maps and data in combination with IHWP method and GIS. This article concludes that buildings alongside the streets with high population and building density, low building quality, far to rescue centers and high level of inclusion represent high rate of vulnerability, compared with other buildings. Also, by moving on from north to south of the zone, the vulnerability increases. Likewise, highways and streets with substantial width and low building and population density hold little values of vulnerability.

A comparison of wood preservatives in posts in southern Mississippi : results from a half-decade of testing

Treesearch

Mike H. Freeman; Douglas Crawford; Patricia Lebow; James A. Brient

2005-01-01

Wood preservatives extend the useful service life of all wooden commodities used above ground and in ground contact, Over SO years ago, the USDA-Forest Products Lab established tests in a high decay and high termite hazard zone in southern Mississippi. During the last five decades, periodic reports have been issued by researchers located at the USDA-FPL, in Madison, WI...

Public speaking for the healthcare professional: Part III--after the program.

PubMed

Baum, Neil

2012-01-01

Public speaking is one of life's greatest fears for many people. However, with practice, repetition, and planning, you can safely leave your comfort zone and make a presentation that will engage the members of the audience, attract their attention, and cause them to take action on your material. This third article in the series will discuss what to do after the last slide is shown.

Experimental Investigation of Inter-Blade Vortices in a Model Francis Turbine

NASA Astrophysics Data System (ADS)

LIU, Demin; LIU, Xiaobing; ZHAO, Yongzhi

2017-07-01

The inter-blade vortex in a Francis turbine becomes one of the main hydraulic factors that are likely to cause blade erosion at deep part load operating conditions. However, the causes and the mechanism of inter-blade vortex are still under investigation according to present researches. Thus the causes of inter-blade vortex and the effect of different hydraulic parameters on the inter-blade vortex are investigated experimentally. The whole life cycle of the inter-blade vortex is observed by a high speed camera. The test results illustrate the whole life cycle of the inter-blade vortex from generation to separation and even to fading. It is observed that the inter-blade vortex becomes stronger with the decreasing of flow and head, which leads to pressure fluctuation. Meanwhile, the pressure fluctuations in the vane-less area and the draft tube section become stronger when inter-blade vortices exist in the blade channel. The turbine will be damaged if operating in the inter-blade vortex zone, so its operating range must be far away from that zone. This paper reveals the main cause of the inter-blade vortex which is the larger incidence angle between the inflow angle and the blade angle on the leading edge of the runner at deep part load operating conditions.

Quantifying area changes of internationally important wetlands due to water consumption in LCA.

PubMed

Verones, Francesca; Pfister, Stephan; Hellweg, Stefanie

2013-09-03

Wetlands harbor diverse species assemblages but are among the world's most threatened ecosystems. Half of their global area was lost during the last century. No approach currently exists in life cycle impact assessment that acknowledges the vulnerability and importance of wetlands globally and provides fate factors for water consumption. We use data from 1184 inland wetlands, all designated as sites of international importance under the Ramsar Convention, to develop regionalized fate factors (FF) for consumptive water use. FFs quantify the change of wetland area caused per m(3)/yr water consumed. We distinguish between surface water-fed and groundwater-fed wetlands and develop FFs for surface water and groundwater consumption. FFs vary over 8 (surface water-fed) and 6 (groundwater-fed) orders of magnitude as a function of the site characteristics, showing the importance of local conditions. Largest FFs for surface water-fed wetlands generally occur in hyper-arid zones and smallest in humid zones, highlighting the dependency on available surface water flows. FFs for groundwater-fed wetlands depend on hydrogeological conditions and vary largely with the total amount of water consumed from the aquifer. Our FFs translate water consumption into wetland area loss and thus become compatible with life cycle assessment methodologies of land use.

Adiposity and height of adult Hmong refugees: relationship with war-related early malnutrition and later migration.

PubMed

Clarkin, Patrick F

2008-01-01

This study investigated whether historical proxies for poor nutrition early in life were associated with differences in body composition and height among adult Hmong refugees. Life history and anthropometric data were collected from a sample of 279 Hmong aged 18-51 years who were born in Laos or Thailand and resettled in French Guiana or the United States following the Second Indochina War. Overall, 30.5% were born in a war zone in Laos, while 38.8% were displaced as infants; these individuals were presumed to have experienced malnutrition in the perinatal and infant periods, respectively. Resettlement in urban areas in the US was utilized as a proxy for greater exposure to excessive energy balance, compared with Hmong who resettled in rural areas in French Guiana. In multiple linear regression models, being displaced in infancy was negatively associated with height after controlling for confounders, while being born in a war zone was associated with higher adiposity and centralized body fat distribution. Resettlement in the US was associated with a higher centralization of subcutaneous fat, but not overall adiposity. These findings may be of interest to the study of the developmental origins of obesity, in a population that has undergone early malnutrition followed by migration and rapid nutritional transition.

Global warming and the regional persistence of a temperate-zone insect (Tenodera sinensis)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rooney, T.P.; Smith, A.T.; Hurd, L.E.

Models based on the paleoecological record predict that animals in temperate regions will respond to global warming by migrating poleward to remain within their temperature tolerance ranges. The effect of global warming on invertebrates is of great concern because of their critical role in ecosystem structure and function. Migration poses a problem for many species because of their limited dispersal abilities. The life cycle of a typical temperature zone univoltine insect. Tenodera sinensis (Mantodea: Mantidae) is constrained by degree-days per season: too few prevent maturation before the killing frost in the autumn; too many allow egg hatch before a killingmore » frost. We used field and laboratory observation on the life history and ecology of this species to predict the effect of global warming on the regional distribution of this insect by the end of the next century. Based on the simplified, best-case, biological assumptions of our model, the geographical range of T. sinensis in eastern North America would be compressed toward the northern part of its present contiguous regional distribution. This and other univoltine temperate species with long maturation periods and low vagility could face regional extinction if global warming predictions are accurate. 61 refs., 3 figs.« less

Terrestrial Zone Exoplanets and Life

NASA Astrophysics Data System (ADS)

Matthews, Brenda

2018-01-01

One of the most exciting results from ALMA has been the detection of significant substructure within protoplanetary disks that can be linked to planet formation processes. For the first time, we are able to observe the process of assembly of material into larger bodies within such disks. It is not possible, however, for ALMA to probe the growth of planets in protoplanetary disks at small radii, i.e., in the terrestrial zone, where we expect rocky terrestrial planets to form. In this regime, the optical depths prohibit observation at the high frequencies observed by ALMA. To probe the effects of planet building processes and detect telltale gaps and signatures of planetary mass bodies at such small separations from the parent star, we require a facility of superior resolution and sensitivity at lower frequencies. The ngVLA is just such a facility. We will present the fundamental science that will be enabled by the ngVLA in protoplanetary disk structure and the formation of planets. In addition, we will discuss the potential for an ngVLA facility to detect the molecules that are the building blocks of life, reaching limits well beyond those reachable with the current generation of telescopes, and also to determine whether such planets will be habitable based on studies of the impact of stars on their nearest planetary neighbours.

Star Masses and Star-Planet Distances for Earth-like Habitability.

PubMed

Waltham, David

2017-01-01

This paper presents statistical estimates for the location and duration of habitable zones (HZs) around stars of different mass. The approach is based upon the assumption that Earth's location, and the Sun's mass, should not be highly atypical of inhabited planets. The results support climate-model-based estimates for the location of the Sun's HZ except models giving a present-day outer-edge beyond 1.64 AU. The statistical approach also demonstrates that there is a habitability issue for stars smaller than 0.65 solar masses since, otherwise, Earth would be an extremely atypical inhabited world. It is difficult to remove this anomaly using the assumption that poor habitability of planets orbiting low-mass stars results from unfavorable radiation regimes either before, or after, their stars enter the main sequence. However, the anomaly is well explained if poor habitability results from tidal locking of planets in the HZs of small stars. The expected host-star mass for planets with intelligent life then has a 95% confidence range of 0.78 M ⊙ < M < 1.04 M ⊙ , and the range for planets with at least simple life is 0.57 M ⊙  < M < 1.64 M ⊙ . Key Words: Habitability-Habitable zone-Anthropic-Red dwarfs-Initial mass function. Astrobiology 17, 61-77.

The zone of social abandonment in cultural geography: on the street in the United States, inside the family in India.

PubMed

Marrow, Jocelyn; Luhrmann, Tanya Marie

2012-09-01

This essay examines the spaces across societies in which persons with severe mental illness lose meaningful social roles and are reduced to "bare life." Comparing ethnographic and interview data from the United States and India, we suggest that these processes of exclusion take place differently: on the street in the United States, and in the family household in India. We argue that cultural, historical, and economic factors determine which spaces become zones of social abandonment across societies. We compare strategies for managing and treating persons with psychosis across the United States and India, and demonstrate that the relative efficiency of state surveillance of populations and availability of public social and psychiatric services, the relative importance of family honor, the extent to which a culture of psychopharmaceutical use has penetrated social life, and other historical features, contribute to circumstances in which disordered Indian persons are more likely to be forcefully "hidden" in domestic space, whereas mentally ill persons in the United States are more likely to be expelled to the street. However, in all locations, social marginalization takes place by stripping away the subject's efficacy in social communication. That is, the socially "dead" lose communicative efficacy, a predicament, following Agamben, we describe as "bare voice."

What's so critical about the critical zone?: New insights at the boundaries between hydrology, pedology, geomorphology, rocks and life (Invited)

NASA Astrophysics Data System (ADS)

Grant, G.

2013-12-01

The great promise of critical zone science and observatories (CZOs) emerging over the past decade was that real progress towards understanding the earth's near-surface environment could be made through coordinated studies of processes and interactions that occur within that thin layer between the bottom of the atmosphere and the top of competent bedrock - the critical zone. How well has this promise been realized, and where is the science now headed? Drawing on recent findings from CZOs and elsewhere, I identify a number of exciting and potentially transformative new ideas and threads at the boundaries of hydrology, geomorphology, pedology, and ecology. These include: 1). New understanding of interactions and feedbacks among soil weathering, pathways for water, tree roots, and bedrock fractures. A fundamental insight emerging from critical zone studies is that soils are far more interestingly structured than simple textbook models of homogeneous substrates with exponentially decreasing permeability with depth. Instead, the near-surface is now seen as a complex network of voids, paths, conduits, and storage zones that are both formed and exploited by the movement of water, geochemical reactions, and organisms. This evolving perspective on the critical zone has implications for a wide range of issues, including the residence time and chemistry of water, rates of weathering, slope stability, and long-term soil fertility. 2. Growing appreciation for the role of biology in conditioning and transforming its own physical environment within the critical zone. This includes the role of trees in hydraulically redistributing water, fracturing bedrock, and contributing to long-term soil erosion and landscape evolution through tree fall and throw and vegetation effects on moisture regimes. 3. Similarly, the importance of understanding linkages among soils, water, and vegetation has never been greater as a warming climate dramatically changes the 'rules of the game'. New understanding of feedbacks among vegetation growth and water uptake, soil moisture regimes, snowpack dynamics, and overall forest health are challenging previous assumptions about how best to manage forest environments in the face of a warming atmosphere and increased frequencies of disturbance. Time will tell whether these new perspectives represent incremental or fundamental shifts in our thinking about the critical zone, but it is clearly an exciting time for critical zone science and scientists.

From an ocean floor wrench zone origin to transpressional tectonic emplacement of the Sithonia ophiolite, eastern Vardar Suture Zone, northern Greece

NASA Astrophysics Data System (ADS)

Bonev, Nikolay; Filipov, Petyo

2017-12-01

In the Hellenides of northern Greece, the Sithonia back-arc ophiolite constitute an element of the Vardar suture zone against the Chortiatis island arc magmatic suite, the Melissochori Formation and the Serbo-Macedonian Massif further north at the Mesozoic continental margin of Eurasia. A granodiorite from the Chortiatis island arc magmatic suite crystallized at 160 Ma as derived from new U-Pb zircon geochronology and confirms the end of arc magmatic activity that started at around 173 Ma. Located southerly of the Chortiatis island arc magmatic suite, the Sithonia ophiolite had igneous life from 159 to 149 Ma, and the ophiolite interfinger with clastic-carbonate Kimmeridgian sediments. Magmatic structures (i.e., sheeted dykes) in the ophiolite witness for NE-trending rift axis, while the transform faults and fracture zones sketch NW-SE transcurrent transtension-like propagation of the rift-spreading center at Sithonia that is consistent with a dextral wrench corridor already proposed for the ophiolite origin in the eastern Vardar zone. The tectonic emplacement of the Sithonia ophiolite involved dextral ENE to SE strike-slip sense of shear and SW and NE reverse thrust sense of shear on mostly steep foliation S1, subhorizontal lineation L1 and associated variably inclined F1 fold axes. This structural grain and kinematics are shared by adjacent Chortiatis island arc magmatic suite and the Melissochori Formation. The coexistence of strike-parallel and thrust components of displacement along discrete dextral strike-slip shear zones and internal deformation of the mentioned units is interpreted to result from a bulk dextral transpressive deformation regime developed in greenschist-facies metamorphic conditions. The back-arc ocean floor previous structural architecture with faults and fracture zones where Kimmeridgian sediments deposited in troughs was used by discrete strike-slip shear zones in which these sediments involved, and the shear zones become the sites for strain partitioning of transpressional deformation. Available biostratigraphic and radiometric age constraints define latest Jurassic-earliest Cretaceous (Tithonian-Berriasian to early Valanginian) time frame for the Sithonia ophiolite northeastward tectonic emplacement accomodated by dextral transpression that led to the ophiolite accretion to the Chortiatis island arc magmatic suite and its trench-fill exposed in the Melissochori Formation and further north toward the Serbo-Macedonian margin of Eurasia.

Palaeobiology, palaeoecology and stratigraphic significance of the Late Miocene cockle Lymnocardium soproniense from Lake Pannon

NASA Astrophysics Data System (ADS)

Magyar, Imre; Cziczer, István; Sztanó, Orsolya; Dávid, Árpád; Johnson, Michael

2016-12-01

Stratigraphic subdivision of the Upper Miocene deposits in the Pannonian Basin has been traditionally based on the endemic mollusc species of Lake Pannon. The cockle species Lymnocardium soproniense Vitális, apparently evolving through a sympatric speciation event in the sublittoral zone of Lake Pannon about 10.2-10.3 Ma, attained wide geographical distribution in the Pannonian basin and thus may serve as a good stratigraphic marker. Lymnocardium soproniense was one of the few large-sized cockles in Lake Pannon, most closely related to its ancestor, L. schedelianum (Fuchs), and to another descendant of the latter, L. variocostatum Vitális. According to the δ18O stable isotope record of its shells, the large size of L. soproniense was coupled with an extended life time of more than 10 years, probably reflecting a stable lake environment with increased resource availability and decreased predation. The species lived in quiet offshore conditions, below the storm wave base, where clay was deposited from suspension and the influence of currents was negligible. The base of the Lymnocardium soproniense Zone in the sublittoral deposits of Lake Pannon is defined by the first occurrence of the species, whereas the top of the zone is marked with the base of the overlying Congeria praerhomboidea Zone, defined by the FAD of C. praerhomboidea.

Assessment of the environmental significance of nutrients and heavy metal pollution in the river network of Serbia.

PubMed

Dević, Gordana; Sakan, Sanja; Đorđević, Dragana

2016-01-01

In this paper, the data for ten water quality variables collected during 2009 at 75 monitoring sites along the river network of Serbia are considered. The results are alarming because 48% of the studied sites were contaminated by Ni, Mn, Pb, As, and nutrients, which are key factors impairing the water quality of the rivers in Serbia. Special attention should be paid to Zn and Cu, listed in the priority toxic pollutants of US EPA for aquatic life protection. The employed Q-model cluster analysis grouped the data into three major pollution zones (low, moderate, and high). Most sites classified as "low pollution zones" (LP) were in the main rivers, whereas those classified as "moderate and high pollution zones" (MP and HP, respectively) were in the large and small tributaries/hydro-system. Principal component analysis/factor analysis (PCA/FA) showed that the dissolved metals and nutrients in the Serbian rivers varied depending on the river, the heterogeneity of the anthropogenic activities in the basins (influenced primarily by industrial wastewater, agricultural activities, and urban runoff pollution), and natural environmental variability, such as geological characteristics. In LP dominated non-point source pollution, such as agricultural and urban runoff, whereas mixed source pollution dominated in the MP and HP zones. These results provide information to be used for developing better pollution control strategies for the river network of Serbia.

Effect of Selected Modeling Assumptions on Subsurface Radionuclide Transport Projections for the Potential Environmental Management Disposal Facility at Oak Ridge, Tennessee

DOE Office of Scientific and Technical Information (OSTI.GOV)

Painter, Scott L.

2016-06-28

The Department of Energy’s Office of Environmental Management recently revised a Remedial Investigation/ Feasibility Study (RI/FS) that included an analysis of subsurface radionuclide transport at a potential new Environmental Management Disposal Facility (EMDF) in East Bear Creek Valley near Oak Ridge, Tennessee. The effect of three simplifying assumptions used in the RI/FS analyses are investigated using the same subsurface pathway conceptualization but with more flexible modeling tools. Neglect of vadose zone dispersion was found to be conservative or non-conservative, depending on the retarded travel time and the half-life. For a given equilibrium distribution coefficient, a relatively narrow range of half-lifemore » was identified for which neglect of vadose zone transport is non-conservative and radionuclide discharge into surface water is non-negligible. However, there are two additional conservative simplifications in the reference case that compensate for the non-conservative effect of neglecting vadose zone dispersion: the use of a steady infiltration rate and vadose zone velocity, and the way equilibrium sorption is used to represent transport in the fractured material of the saturated aquifer. With more realistic representations of all three processes, the RI/FS reference case was found to either provide a reasonably good approximation to the peak concentration or was significantly conservative (pessimistic) for all parameter combinations considered.« less

Oil biodegradation. Water droplets in oil are microhabitats for microbial life.

PubMed

Meckenstock, Rainer U; von Netzer, Frederick; Stumpp, Christine; Lueders, Tillmann; Himmelberg, Anne M; Hertkorn, Norbert; Schmitt-Kopplin, Philipp; Harir, Mourad; Hosein, Riad; Haque, Shirin; Schulze-Makuch, Dirk

2014-08-08

Anaerobic microbial degradation of hydrocarbons, typically occurring at the oil-water transition zone, influences the quality of oil reservoirs. In Pitch Lake, Trinidad and Tobago--the world's largest asphalt lake--we found that microorganisms are metabolically active in minuscule water droplets (1 to 3 microliters) entrapped in oil. Pyrotag sequencing of individual droplet microbiomes revealed complex methanogenic microbial communities actively degrading the oil into a diverse range of metabolites, as shown by nuclear magnetic resonance and Fourier transform ion cyclotron resonance mass spectrometry. High salinity and water-stable isotopes of the droplets indicate a deep subsurface origin. The 13.5% water content and the large surface area of the droplets represent an underestimated potential for biodegradation of oil away from the oil-water transition zone. Copyright © 2014, American Association for the Advancement of Science.

Effect of Pulse Parameters on Weld Quality in Pulsed Gas Metal Arc Welding: A Review

NASA Astrophysics Data System (ADS)

Pal, Kamal; Pal, Surjya K.

2011-08-01

The weld quality comprises bead geometry and its microstructure, which influence the mechanical properties of the weld. The coarse-grained weld microstructure, higher heat-affected zone, and lower penetration together with higher reinforcement reduce the weld service life in continuous mode gas metal arc welding (GMAW). Pulsed GMAW (P-GMAW) is an alternative method providing a better way for overcoming these afore mentioned problems. It uses a higher peak current to allow one molten droplet per pulse, and a lower background current to maintain the arc stability. Current pulsing refines the grains in weld fusion zone with increasing depth of penetration due to arc oscillations. Optimum weld joint characteristics can be achieved by controlling the pulse parameters. The process is versatile and easily automated. This brief review illustrates the effect of pulse parameters on weld quality.

Neurogenesis in the aging brain.

PubMed

Apple, Deana M; Solano-Fonseca, Rene; Kokovay, Erzsebet

2017-10-01

Adult neurogenesis is the process of producing new neurons from neural stem cells (NSCs) for integration into the brain circuitry. Neurogenesis occurs throughout life in the ventricular-subventricular zone (V-SVZ) of the lateral ventricle and the subgranular zone (SGZ) of the hippocampal dentate gyrus. However, during aging, NSCs and their progenitors exhibit reduced proliferation and neuron production, which is thought to contribute to age-related cognitive impairment and reduced plasticity that is necessary for some types of brain repair. In this review, we describe NSCs and their niches during tissue homeostasis and how they undergo age-associated remodeling and dysfunction. We also discuss some of the functional ramifications in the brain from NSC aging. Finally, we discuss some recent insights from interventions in NSC aging that could eventually translate into therapies for healthy brain aging. Copyright © 2017 Elsevier Inc. All rights reserved.

Geospatial Approach on Landslide Hazard Zonation Mapping Using Multicriteria Decision Analysis: A Study on Coonoor and Ooty, Part of Kallar Watershed, The Nilgiris, Tamil Nadu

NASA Astrophysics Data System (ADS)

Rahamana, S. Abdul; Aruchamy, S.; Jegankumar, R.

2014-12-01

Landslides are one of the critical natural phenomena that frequently lead to serious problems in hilly area, resulting to loss of human life and property, as well as causing severe damage to natural resources. The local geology with high degree of slope coupled with high intensity of rainfall along with unplanned human activities of the study area causes many landslides in this region. The present study area is more attracted by tourist throughout the year, so this area must be considered for preventive measures. Geospatial based Multicriteria decision analysis (MCDA) technique is increasingly used for landslide vulnerability and hazard zonation mapping. It enables the integration of different data layers with different levels of uncertainty. In this present study, it is used analytic hierarchy process (AHP) method to prepare landslide hazard zones of the Coonoor and Ooty, part of Kallar watershed, The Nilgiris, Tamil Nadu. The study was carried out using remote sensing data, field surveys and geographic information system (GIS) tools. The ten factors that influence landslide occurrence, such as elevation, slope aspect, slope angle, drainage density, lineament density, soil, precipitation, land use/land cover (LULC), distance from road and NDVI were considered. These factors layers were extracted from the various related spatial data's. These factors were evaluated, and then, the individual factor weight and class weight were assigned to each of the related factors. The Landslide Hazard Zone Index (LHZI) was calculated using Multicriteria decision analysis (MCDA) the technique based on the assigned weight and the rating is given by the Analytical Hierarchy Process (AHP) method. The final cumulative map of the study area was categorized into four hazard zones and classified as zone I to IV. There are 3.56% of the area comes under the hazard zone IV fallowed by 48.19% of the area comes under zone III, 43.63 % of the area in zone II and 4.61% of the area comes hazard zone I. Further resulted hazard zone map and landuse/landcover map are overlaid to check the hazard status, and existing inventory of known landslides within the present study area was compared with the resulting vulnerable and hazard zone maps. The landslide hazard zonation map is useful for landslide hazard prevention, mitigation, and improvement to society, and proper planning for land use and construction in the future.

Effect of the 5-HTTLPR polymorphism on posttraumatic stress disorder, depression, anxiety, and quality of life among Iraq and Afghanistan veterans

PubMed Central

Kimbrel, Nathan A.; Morissette, Sandra B.; Meyer, Eric C.; Chrestman, Roberta; Jamroz, Robert; Silvia, Paul J.; Beckham, Jean C.; Young, Keith A.

2015-01-01

Background Posttraumatic stress disorder (PTSD), depression, anxiety, and stress are significant problems among returning veterans and are associated with reduced quality of life. Design A correlational design was used to examine the impact of a polymorphism (5-HTTLPR) in the serotonin transporter promoter gene on post-deployment adjustment among returning veterans. Methods A total of 186 returning Iraq and Afghanistan veterans were genotyped for the 5-HTTLPR polymorphism. Symptoms of PTSD, depression, general stress, and anxiety were assessed along with quality of life. Results After controlling for combat exposure, age, sex of the participant, and race, 5-HTTLPR had a significant multivariate effect on post-deployment adjustment, such that S′ carriers reported more post-deployment adjustment problems and worse quality of life than veterans homozygous for the L′ allele. This effect was larger when the analyses were restricted to veterans of European ancestry. Conclusions Our findings suggest that veterans who carry the S′ allele of the 5-HTTLPR polymorphism may be at increased risk for adjustment problems and reduced quality of life following deployments to war zones. PMID:25314020

The Search for Life on Mars

NASA Technical Reports Server (NTRS)

Mumma, Michael J.

2012-01-01

For centuries, the planet Mars has been regarded as a possible abode for life. Serious searches for the signatures of life began in the 19th century, and continue via telescopic investigations and landed missions. While early work focused on phenomenology and bordered on fantasy, modern scientific inquiry has emphasized the search for chemical signatures of life in the soil and rocks at the planet's surface, and the search for biomarker gases in the atmosphere. Living systems produce more than 90% of Earth's atmospheric methane; the balance is of geochemical origin. The discovery of methane on Mars will be described, along with the ongoing extended search for clues to its origins. The possible origins of Mars methane will be discussed in the context of terrestrial analogue sites where geologic and biologic methane production now occurs - ranging from sub-permafrost zones in the arctic to hydrothermal vents in the deep ocean. Terrestrial organisms that could prosper on Mars today will be mentioned. I will briefly touch upon experiments conducted by landed spacecraft, ranging from the Viking Life Science Experiments in 1976 to the impending Mars Science laboratory, and the Trace Gas Orbiter and ExoMars missions now being developed for flight in the coming decade.

Quantification of the Service Life Extension and Environmental Benefit of Chloride Exposed Self-Healing Concrete.

PubMed

Van Belleghem, Bjorn; Van den Heede, Philip; Van Tittelboom, Kim; De Belie, Nele

2016-12-23

Formation of cracks impairs the durability of concrete elements. Corrosion inducing substances, such as chlorides, can enter the matrix through these cracks and cause steel reinforcement corrosion and concrete degradation. Self-repair of concrete cracks is an innovative technique which has been studied extensively during the past decade and which may help to increase the sustainability of concrete. However, the experiments conducted until now did not allow for an assessment of the service life extension possible with self-healing concrete in comparison with traditional (cracked) concrete. In this research, a service life prediction of self-healing concrete was done based on input from chloride diffusion tests. Self-healing of cracks with encapsulated polyurethane precursor formed a partial barrier against immediate ingress of chlorides through the cracks. Application of self-healing concrete was able to reduce the chloride concentration in a cracked zone by 75% or more. As a result, service life of steel reinforced self-healing concrete slabs in marine environments could amount to 60-94 years as opposed to only seven years for ordinary (cracked) concrete. Subsequent life cycle assessment calculations indicated important environmental benefits (56%-75%) for the ten CML-IA (Center of Environmental Science of Leiden University-Impact Assessment) baseline impact indicators which are mainly induced by the achievable service life extension.

New numerical determination of habitability in the Galaxy: the SETI connection

NASA Astrophysics Data System (ADS)

Ramirez, Rodrigo; Gómez-Muñoz, Marco A.; Vázquez, Roberto; Núñez, Patricia G.

2018-01-01

In this paper, we determine the habitability of Sun-like stars in the Galaxy using Monte Carlo simulations, which are guided by the factors of the Drake Equation for the considerations on the astrophysical and biological parameters needed to generate and maintain life on a planet's surface. We used a simple star distribution, initial mass function and star formation history to reproduce the properties and distribution of stars within the Galaxy. Using updated exoplanet data from the Kepler mission, we assign planets to some of the stars, and then follow the evolution of life on the planets that met the habitability criteria using two different civilization hypotheses. We predict that around 51% of Earth-like planets in the habitable zone (HZ) are inhabited by primitive life and 4% by technological life. We apply the results to the Kepler field of view, and predicted that there should be at least six Earth-like planets in the HZ, three of them inhabited by primitive life. According to our model, non-technological life is very common if there are the right conditions, but communicative civilizations are less likely to exist and detect. Nonetheless, we predict a considerable number of detectable civilizations within our Galaxy, making it worthwhile to keep searching.

PLANET TOPERS: Planets, Tracing the Transfer, Origin, Preservation, and Evolution of their ReservoirS

NASA Astrophysics Data System (ADS)

Dehant, Véronique; Breuer, Doris; Claeys, Philippe; Debaille, Vinciane; de Keyser, Johan; Javaux, Emmanuelle; Goderis, Steven; Karatekin, Ozgur; Matielli, Nadine; Noack, Lena; Spohn, Tilman; Carine Vandaele, Ann; Vanhaecke, Frank; van Hoolst, Tim; Wilquet, Valérie; The PLANET Topers Team

2015-04-01

The PLANET TOPERS (Planets, Tracing the Transfer, Origin, Preservation, and Evolution of their ReservoirS) group is an Inter-university attraction pole (IAP) addressing the question of habitability in our Solar System. Based on the only known example of Earth, the concept refers to whether environmental conditions are available that could eventually support life, even if life does not currently exist. Life is believed to require liquid water, but important geodynamic processes affect the habitability conditions of a planet. The PLANET TOPERS group develops and closely integrates the geophysical, geological, and biological aspects of habitability with a particular focus on Earth neighboring planets, Mars and Venus. Habitability is commonly understood as "the potential of an environment (past or present) to support life of any kind" (Steele et al., 2005). Based on the only known example of Earth, the concept refers to whether environmental conditions are available that could eventually support life, even if life does not currently exist (Javaux and Dehant, 2010). Life includes properties such as consuming nutrients and producing waste, the ability to reproduce and grow, pass on genetic information, evolve, and adapt to the varying conditions on a planet (Sagan, 1970). Terrestrial life requires liquid water. The common view, however, is that extraterrestrial life would probably be based on organic chemistry in a water solvent (Pace, 2001) although alternative biochemistries have been hypothesized. The stability of liquid water at the surface of a planet defines a habitable zone (HZ) around a star. In the Solar System, it stretches between Venus and Mars, but excludes these two planets. If the greenhouse effect is taken into account, the habitable zone may have included early Mars while the case for Venus is still debated. The dynamic processes, e.g. internal dynamo, magnetic field, atmosphere, plate tectonics, mantle convection, volcanism, thermo-tectonic evolution, meteorite impacts, and erosion, modify the planetary surface, the possibility to have liquid water, the thermal state, the energy budget and the availability of nutrients. Shortly after formation (Hadean 4.4-4.0 Ga), evidence supports the presence of a liquid ocean and continental crust on Earth (Wilde et al., 2001), Earth may thus have been habitable very early on (Strasdeit, 2010). The origin of life is not understood yet but the oldest putative traces of life occur in the early Archaean (~3.5 Ga). The extreme values of environmental conditions in which life thrives today can also be used to characterize the "envelope" of the existence of life and the range of potential extraterrestrial habitats. The requirement of nutrients for biosynthesis, growth, and reproduction suggests that a tectonically active planet, with liquid water is required to replenish nutrients and sustain life (as currently known). These dynamic processes play a key role in the apparition and persistence of life. Mars is presently on the edge of the HZ, but may have been much more hospitable early in its history, as the examination of its surface suggests the existence of water very early on (about 4 Ga ago) (Bibring et al., 2005; 2006). Since then, Mars lost most of its atmosphere, preventing the presence of liquid water at the surface. In comparison Earth is habitable at present and has been for at least 3.5 Ga.

Johnson Space Center's regenerative life support systems test bed

NASA Technical Reports Server (NTRS)

Henninger, Donald L.; Tri, Terry O.; Barta, Daniel J.; Stahl, Randal S.

1991-01-01

The Regenerative Life Support System (RLSS) Test Bed at NASA's Johnson Space Center is an atmospherically closed, controlled environment facility for the evaluation of regenerative life support systems using higher plants in conjunction with physicochemical life support systems. When completed, the facility will be comprised of two large scale plant growth chambers, each with approximately 10 m(exp 2) growing area. One of the two chambers, the Variable Pressure Growth Chamber (VPGC), will be capable of operating at lower atmospheric pressures to evaluate a range of environments that may be used in Lunar or Martian habitats; the other chamber, the Ambient Pressure Growth Chamber (APGC) will operate at ambient atmospheric pressure. The root zone in each chamber will be configurable for hydroponic or solid state media systems. Research will focus on: (1) in situ resource utilization for CELSS systems, in which simulated lunar soils will be used in selected crop growth studies; (2) integration of biological and physicochemical air and water revitalization systems; (3) effect of atmospheric pressure on system performance; and (4) monitoring and control strategies.

Fatigue behavior of a 2XXX series aluminum alloy reinforced with 15 vol Pct SiCp

NASA Astrophysics Data System (ADS)

Bonnen, J. J.; Allison, J. E.; Jones, J. W.

1991-05-01

The fatigue behavior of a naturally aged powder metallurgy 2xxx series aluminum alloy (Alcoa MB85) and a composite made of this alloy with 15 vol pct SiCp, has been investigated. Fatigue lives were determined using load-controlled axial testing of unnotched cylindrical samples. The influence of mean stress was determined at stress ratios of -1, 0.1, and 0.7. Mean stress had a significant influence on fatigue life, and this influence was consistent with that normally observed in metals. At each stress ratio, the incorporation of SiC reinforcement led to an increase in fatigue life at low and intermediate stresses. When considered on a strain-life basis, however, the composite materials had a somewhat inferior resistance to fatigue. Fatigue cracks initiated from several different microstructural features or defect types, but fatigue life did not vary significantly with the specific initiation site. As the fatigue crack advanced away from the fatigue crack initiation site, increasing numbers of SiC particles were fractured, in agreement with crack-tip process zone models.

2013 - Life is a Cosmic Phenomenon : The "Search for Water" evolves into the "Search for Life"

NASA Astrophysics Data System (ADS)

Smith, William E.

2013-03-01

We propose that the 2013 data from the Kepler Mission (giving a current estimate of the number of earth-like planets in the habitable zone of sun-like stars as 144 billion), has caused a consciousness change in human belief in the probability of life off earth. This seems to have affected NASA's public statements which are now leaning to the more visionary mission goal of the "Search for Life" rather than the 1975-2012 focus of the "Search for Water". We propose that the first confirmed earth-like planet, expected to be announced later this year, be called "BORUCKI" in honour of the visionary USA scientist Bill Borucki, the father of the Kepler Mission. We explore the 2013 status of the Hoyle-Wickramasinghe Model of Panspermia, its hypothesis, propositions, experiments and evidence. We use the Karl Popper model for scientific hypotheses (1). Finally we explore Sir Fred Hoyle's vision of a planetary microbe defense system we call the Hoyle Shield. We explore the subsystem components of the shield and assess some options for these components using break-though technologies already available.

Monte Carlo calculations of the incineration of plutonium and minor actinides of laser fusion inertial confinement fusion fission energy (LIFE) engine

NASA Astrophysics Data System (ADS)

Adem, ACIR; Eşref, BAYSAL

2018-07-01

In this paper, neutronic analysis in a laser fusion inertial confinement fusion fission energy (LIFE) engine fuelled plutonium and minor actinides using a MCNP codes was investigated. LIFE engine fuel zone contained 10 vol% TRISO particles and 90 vol% natural lithium coolant mixture. TRISO fuel compositions have Mod①: reactor grade plutonium (RG-Pu), Mod②: weapon grade plutonium (WG-Pu) and Mod③: minor actinides (MAs). Tritium breeding ratios (TBR) were computed as 1.52, 1.62 and 1.46 for Mod①, Mod② and Mod③, respectively. The operation period was computed as ∼21 years when the reference TBR > 1.05 for a self-sustained reactor for all investigated cases. Blanket energy multiplication values (M) were calculated as 4.18, 4.95 and 3.75 for Mod①, Mod② and Mod③, respectively. The burnup (BU) values were obtained as ∼1230, ∼1550 and ∼1060 GWd tM–1, respectively. As a result, the higher BU were provided with using TRISO particles for all cases in LIFE engine.

Creating Habitable Zones, at all Scales, from Planets to Mud Micro-Habitats, on Earth and on Mars

NASA Astrophysics Data System (ADS)

Nisbet, Euan; Zahnle, Kevin; Gerasimov, M. V.; Helbert, Jörn; Jaumann, Ralf; Hofmann, Beda A.; Benzerara, Karim; Westall, Frances

The factors that create a habitable planet are considered at all scales, from planetary inventories to micro-habitats in soft sediments and intangibles such as habitat linkage. The possibility of habitability first comes about during accretion, as a product of the processes of impact and volatile inventory history. To create habitability water is essential, not only for life but to aid the continual tectonic reworking and erosion that supply key redox contrasts and biochemical substrates to sustain habitability. Mud or soft sediment may be a biochemical prerequisite, to provide accessible substrate and protection. Once life begins, the habitat is widened by the activity of life, both by its management of the greenhouse and by partitioning reductants (e.g. dead organic matter) and oxidants (including waste products). Potential Martian habitats are discussed: by comparison with Earth there are many potential environmental settings on Mars in which life may once have occurred, or may even continue to exist. The long-term evolution of habitability in the Solar System is considered.

Creating Habitable Zones, at all Scales, from Planets to Mud Micro-Habitats, on Earth and on Mars

NASA Astrophysics Data System (ADS)

Nisbet, Euan; Zahnle, Kevin; Gerasimov, M. V.; Helbert, Jörn; Jaumann, Ralf; Hofmann, Beda A.; Benzerara, Karim; Westall, Frances

2007-03-01

The factors that create a habitable planet are considered at all scales, from planetary inventories to micro-habitats in soft sediments and intangibles such as habitat linkage. The possibility of habitability first comes about during accretion, as a product of the processes of impact and volatile inventory history. To create habitability water is essential, not only for life but to aid the continual tectonic reworking and erosion that supply key redox contrasts and biochemical substrates to sustain habitability. Mud or soft sediment may be a biochemical prerequisite, to provide accessible substrate and protection. Once life begins, the habitat is widened by the activity of life, both by its management of the greenhouse and by partitioning reductants (e.g. dead organic matter) and oxidants (including waste products). Potential Martian habitats are discussed: by comparison with Earth there are many potential environmental settings on Mars in which life may once have occurred, or may even continue to exist. The long-term evolution of habitability in the Solar System is considered.

Avian studies and research opportunities in the Luquillo Experimental Forest: a tropical rain forest in Puerto Rico

Treesearch

Joseph Wunderle, Jr; Wayne J. Arendt

2011-01-01

The Luquillo Experimental Forest (LEF) located on the Caribbean island of Puerto Rico has a rich history of ecological research, including a variety of avian studies, and is one of the most active ecological research sites in the Neotropics. The LEF spans an elevational range from 100 to 1075mover which five life zones and four forest types are found in a warm, humid...

Effects of logging on streamflow, sedimentation, fish life, and fish habitat in the north coast redwood-Douglas-fir type - Jackson State Forest, Fort Bragg, California

Treesearch

Robert R. Ziemer; Eugene Kojan; Robert B. Thomas

1965-01-01

In 1961, cooperative watershed management research in the Lower Conifer Zone of California was started. Currently, the research is being conducted by the Pacific Southwest Forest and Range Experiment Station of the U. S. Forest Service with the cooperation of the State of California, Department of Water Resources, and the Division of Forestry. Recently, the Station...

Initial, Cockpit Anthropometric Assessment of U.S. Navy T-6 Life Support Equipment

DTIC Science & Technology

2007-11-05

DEP was not specified. Zone 1, 2, and 3 reach conditions to controls and pedals and clearances were in accordance with military standard...functional leg reach as operation of pedals ; cockpit volume clearances, including ejection clearances not striking objects unintention-ally; and overhead...was measured from knee to any obstruction. Reach to pedals was measured from a position where full control was achieved. Arm reach was measured for

Assessing Sentiment In Conflict Zones Through Social Media

DTIC Science & Technology

2016-12-01

Happiness and the Patterns of Life: A Study of Geolocated Tweets,” Scientific Reports 3 (2013); Bartosz Hawelka et al., “Geo-Located Twitter as...Geography of Twitter,” First Monday 18, no. 5 (2013); Lewis Mitchell et al., “The Geography of Happiness : Connecting Twitter Sentiment and...Barcelona, Spain: AAAI Press, July 2011), 1–10; Peter Sheridan Dodds et al., “Temporal Patterns of Happiness and Information in a Global Social Network

Educating the Communists of the Future: Notes on the Educational Life of the Spanish Children Evacuated to the USSR during the Spanish Civil War

ERIC Educational Resources Information Center

Sierra Blas, Verónica

2015-01-01

The high rate of child mortality registered during the early months of the Civil War led the Republican authorities to initiate several operations to evacuate youngsters with the purpose of protecting and saving the children of Spain. At the beginning, the children were evacuated to zones in the interior of the country far removed from the front…

JPRS Report, Science & Technology, Europe

DTIC Science & Technology

1991-12-30

not yet found a market. Like the ingenious blood-clot filter designed to prevent embolization . Rec- tilinear in its low-temperature phase, enabling...them to turn carbon dioxide and water into the "building blocks of life:" carbohy- drates, fats , and nucleic acids. Natural systems are not only one...structure of the device developed by the MFKI is that it is completely smooth, there are no fractured surfaces at the border of the active zone. The

A New Empirical Constraint on the Prevalence of Technological Species in the Universe.

PubMed

Frank, A; Sullivan, W T

2016-05-01

In this article, we address the cosmic frequency of technological species. Recent advances in exoplanet studies provide strong constraints on all astrophysical terms in the Drake equation. Using these and modifying the form and intent of the Drake equation, we set a firm lower bound on the probability that one or more technological species have evolved anywhere and at any time in the history of the observable Universe. We find that as long as the probability that a habitable zone planet develops a technological species is larger than ∼10(-24), humanity is not the only time technological intelligence has evolved. This constraint has important scientific and philosophical consequences. Life-Intelligence-Extraterrestrial life. Astrobiology 2016, 359-362.

Subsurface microbial habitats on Mars

NASA Technical Reports Server (NTRS)

Boston, P. J.; Mckay, C. P.

1991-01-01

We developed scenarios for shallow and deep subsurface cryptic niches for microbial life on Mars. Such habitats could have considerably prolonged the persistence of life on Mars as surface conditions became increasingly inhospitable. The scenarios rely on geothermal hot spots existing below the near or deep subsurface of Mars. Recent advances in the comparatively new field of deep subsurface microbiology have revealed previously unsuspected rich aerobic and anaerobic microbal communities far below the surface of the Earth. Such habitats, protected from the grim surface conditions on Mars, could receive warmth from below and maintain water in its liquid state. In addition, geothermally or volcanically reduced gases percolating from below through a microbiologically active zone could provide the reducing power needed for a closed or semi-closed microbial ecosystem to thrive.

Life cycle cost optimization of biofuel supply chains under uncertainties based on interval linear programming.

PubMed

Ren, Jingzheng; Dong, Liang; Sun, Lu; Goodsite, Michael Evan; Tan, Shiyu; Dong, Lichun

2015-01-01

The aim of this work was to develop a model for optimizing the life cycle cost of biofuel supply chain under uncertainties. Multiple agriculture zones, multiple transportation modes for the transport of grain and biofuel, multiple biofuel plants, and multiple market centers were considered in this model, and the price of the resources, the yield of grain and the market demands were regarded as interval numbers instead of constants. An interval linear programming was developed, and a method for solving interval linear programming was presented. An illustrative case was studied by the proposed model, and the results showed that the proposed model is feasible for designing biofuel supply chain under uncertainties. Copyright © 2015 Elsevier Ltd. All rights reserved.

Detecting Atmospheric Biosignatures of Transiting Exoplanets in the Mid-IR

NASA Astrophysics Data System (ADS)

Stevenson, Kevin

2018-01-01

For the first time in human history, our generation will have the technology needed to answer one of the longest-standing questions: "Are we alone?'' Only recently have planet-hunting programs (such as TRAPPIST, MEarth, and Kepler) confirmed the first Earth analogues orbiting M dwarfs. However, it is unknown whether planets orbiting the most ubiquitous stars in our galaxy can support life. I will discuss the challenges and opportunities of looking for biosignatures in transiting exoplanet atmospheres at mid-infrared wavelengths and argue that the only way to ascertain the truth is to make a measurement. I will also present how a survey of nearby mid-to-late M dwarfs could empirically determine the fraction of habitable-zone planets that develop life.

Unusual larval habitats and life history of chironomid (Diptera) genera

USGS Publications Warehouse

Hudson, Patrick L.

1987-01-01

Ninety-three genera, representing all subfamilies of Chironomidae, are organized into 9 categories of unusual habitats or life history including hygropetric, riparian (bank, floodplain, upland), hyporheic, symbiotic, and intertidal; others live in water held in plants or mine into unusual substrates. In riparian zones precise location of optimum habitat is difficult to determine as is definition of habitat within the continuum from shoreline to upland areas. The ecological importance of the riparian group appears to lie in its processing of coarse particulate matter along the floodplain of streams and rivers. All riparian genera are zoogeographically useful and can be used in reconstructing evolutionary dispersal pathways because they are adapted to unique habits that have remained largely undisturbed by human activities.

If they are there, where are they?

NASA Astrophysics Data System (ADS)

Anand, Rajagopal

2017-04-01

The famous Fermi Paradox questioning the existence of extraterrestrial intelligence can be put to rest. Astrophysicists and astronomers have spent decades decoding the mysteries of the Universe based on the physical laws formulated by intellectual human beings based mostly on observations and investigations carried out in terrestrial and space laboratories and through mathematical calculations to establish the physical possibility of existence of intelligence outside our planet. The proximity of a planet from its star, luminosity of the star, the presence of molecular oxygen in the planet's atmosphere, presence of liquid water, the size and density of the planet, age of the star and eccentricity of the planet's orbit around its star are the usual points pondered upon while finding a theory for the existence of extra terrestrial intelligence. The Kepler mission has identified over 1000 exoplanets in over 400 stellar systems in the galactic habitable zone and an estimate of about 11 billion exoplanets are speculated to be orbiting stars similar to Sun. But signs of life are yet to be confirmed. Getting back to the Fermi Paradox, where then is everybody? One possible scenario we can realise from the planetary properties of our very Earth. The sidereal rotation period of the Earth around its axis is 0.99726968 d which is equivalent to 23h 56m 4.1s, approximated to one day. The semi-major axis of the Earth's elliptical orbit with an eccentricity of 0.01671123 around the Sun is 149598261 km or 1.00000261 AU and the orbital period is 365.256363004 d. The hint is probably here. The Earth goes around its star in 360 odd days (a full circle) to complete one revolution in its orbit. This observation can result in a hypothesis that a planet which goes around its star with a periodicity of 360 odd planetary days is the suitable candidate for hosting life. This clearly rules out a planet such as Mars, which has a sidereal rotation period similar to that of Earth (1.026 d) and an orbital period of 687 days, to be a probable candidate to support life. Therefore, it is not just a planet's position in the so-called galactic habitable zone that is paramount in determining the possibility of hosting life but rather its periodicity around its star is. The habitable zone should therefore not depend on the 1 AU distance of a planet from its star but on the periodicity of 360 planetary days of a planet's travel in its orbit around its star. The extraterrestrial intelligence search missions should consequently focus on identifying candidates fulfilling the above rule. Plate tectonics - the principal supplier of life-supporting energy and matter through recycling - operating in the Earth, and its conspicuous absence elsewhere, may also be a result of this orbital periodicity. Rest of the details such as the luminosity of a star as well as processes such as atmospheric evolution on Earth might fall in line.

Fine morphology of the jaw apparatus of Puncturella noachina (Fissurellidae, Vetigastropoda).

PubMed

Vortsepneva, Elena; Ivanov, Dmitry; Purschke, Günter; Tzetlin, Alexander

2014-07-01

Jaws of various kinds occur in virtually all groups of Mollusca, except for Polyplacophora and Bivalvia. Molluscan jaws are formed by the buccal epithelium and either constitute a single plate, a paired formation or a serial structure. Buccal ectodermal structures in gastropods are rather different. They can be nonrenewable or having final growth, like the hooks in Clione (Gastropoda, Gymnosomata). In this case, they are formed by a single cell. Conversely, they can be renewable during the entire life span and in this case they are formed by a set of cells, like the formation of the radula. The fine structure of the jaws was studied in the gastropod Puncturella noachina. The jaw is situated in the buccal cavity and consists of paired elongated cuticular plates. On the anterior edge of each cuticular plate there are numerous longitudinally oriented rodlets disposed over the entire jaw surface and immersed into a cuticular matrix. The jaw can be divided into four zones situated successively toward the anterior edge: 1) the posterior area: the zone of formation of the thick cuticle covering the entire jaw and forming the electron-dense outer layer of the jaw plate; 2) the zone of rodlet formation; 3) the zone of rodlet arrangement; and 4) the anterior zone: the free scraping edge of the plate, or the erosion zone. In the general pattern of jaw formation, Puncturella noachina resembles Testudinalia tessulata (Patellogastropoda) studied previously. The basis of the jaw is a cuticular plate formed by the activity of the strongly developed microvillar apparatus of the gnathoepithelium. However, the mechanism of renewal of the jaw anterior part in P. noachina is much more complex as its scraping edge consists not just of a thick cuticular matrix rather than of a system of denticles being the projecting endings of rodlets. © 2014 Wiley Periodicals, Inc.

Tidal Heating of Earth-like Exoplanets around M Stars: Thermal, Magnetic, and Orbital Evolutions

PubMed Central

Barnes, R.

2015-01-01

Abstract The internal thermal and magnetic evolution of rocky exoplanets is critical to their habitability. We focus on the thermal-orbital evolution of Earth-mass planets around low-mass M stars whose radiative habitable zone overlaps with the “tidal zone,” where tidal dissipation is expected to be a significant heat source in the interior. We develop a thermal-orbital evolution model calibrated to Earth that couples tidal dissipation, with a temperature-dependent Maxwell rheology, to orbital circularization and migration. We illustrate thermal-orbital steady states where surface heat flow is balanced by tidal dissipation and cooling can be stalled for billions of years until circularization occurs. Orbital energy dissipated as tidal heat in the interior drives both inward migration and circularization, with a circularization time that is inversely proportional to the dissipation rate. We identify a peak in the internal dissipation rate as the mantle passes through a viscoelastic state at mantle temperatures near 1800 K. Planets orbiting a 0.1 solar-mass star within 0.07 AU circularize before 10 Gyr, independent of initial eccentricity. Once circular, these planets cool monotonically and maintain dynamos similar to that of Earth. Planets forced into eccentric orbits can experience a super-cooling of the core and rapid core solidification, inhibiting dynamo action for planets in the habitable zone. We find that tidal heating is insignificant in the habitable zone around 0.45 (or larger) solar-mass stars because tidal dissipation is a stronger function of orbital distance than stellar mass, and the habitable zone is farther from larger stars. Suppression of the planetary magnetic field exposes the atmosphere to stellar wind erosion and the surface to harmful radiation. In addition to weak magnetic fields, massive melt eruption rates and prolonged magma oceans may render eccentric planets in the habitable zone of low-mass stars inhospitable for life. Key Words: Tidal dissipation—Thermal history—Planetary interiors—Magnetic field. Astrobiology 15, 739–760. PMID:26393398

Tidal Heating of Earth-like Exoplanets around M Stars: Thermal, Magnetic, and Orbital Evolutions.

PubMed

Driscoll, P E; Barnes, R

2015-09-01

The internal thermal and magnetic evolution of rocky exoplanets is critical to their habitability. We focus on the thermal-orbital evolution of Earth-mass planets around low-mass M stars whose radiative habitable zone overlaps with the "tidal zone," where tidal dissipation is expected to be a significant heat source in the interior. We develop a thermal-orbital evolution model calibrated to Earth that couples tidal dissipation, with a temperature-dependent Maxwell rheology, to orbital circularization and migration. We illustrate thermal-orbital steady states where surface heat flow is balanced by tidal dissipation and cooling can be stalled for billions of years until circularization occurs. Orbital energy dissipated as tidal heat in the interior drives both inward migration and circularization, with a circularization time that is inversely proportional to the dissipation rate. We identify a peak in the internal dissipation rate as the mantle passes through a viscoelastic state at mantle temperatures near 1800 K. Planets orbiting a 0.1 solar-mass star within 0.07 AU circularize before 10 Gyr, independent of initial eccentricity. Once circular, these planets cool monotonically and maintain dynamos similar to that of Earth. Planets forced into eccentric orbits can experience a super-cooling of the core and rapid core solidification, inhibiting dynamo action for planets in the habitable zone. We find that tidal heating is insignificant in the habitable zone around 0.45 (or larger) solar-mass stars because tidal dissipation is a stronger function of orbital distance than stellar mass, and the habitable zone is farther from larger stars. Suppression of the planetary magnetic field exposes the atmosphere to stellar wind erosion and the surface to harmful radiation. In addition to weak magnetic fields, massive melt eruption rates and prolonged magma oceans may render eccentric planets in the habitable zone of low-mass stars inhospitable for life.

Microbial gardening in the ocean's twilight zone: detritivorous metazoans benefit from fragmenting, rather than ingesting, sinking detritus: fragmentation of refractory detritus by zooplankton beneath the euphotic zone stimulates the harvestable production of labile and nutritious microbial biomass.

PubMed

Mayor, Daniel J; Sanders, Richard; Giering, Sarah L C; Anderson, Thomas R

2014-12-01

Sinking organic particles transfer ∼10 gigatonnes of carbon into the deep ocean each year, keeping the atmospheric CO2 concentration significantly lower than would otherwise be the case. The exact size of this effect is strongly influenced by biological activity in the ocean's twilight zone (∼50-1,000 m beneath the surface). Recent work suggests that the resident zooplankton fragment, rather than ingest, the majority of encountered organic particles, thereby stimulating bacterial proliferation and the deep-ocean microbial food web. Here we speculate that this apparently counterintuitive behaviour is an example of 'microbial gardening', a strategy that exploits the enzymatic and biosynthetic capabilities of microorganisms to facilitate the 'gardener's' access to a suite of otherwise unavailable compounds that are essential for metazoan life. We demonstrate the potential gains that zooplankton stand to make from microbial gardening using a simple steady state model, and we suggest avenues for future research. © 2014 The Authors. Bioessays published by WILEY Periodicals, Inc.

Pharmacogenomic identification of small molecules for lineage specific manipulation of subventricular zone germinal activity.

PubMed

Azim, Kasum; Angonin, Diane; Marcy, Guillaume; Pieropan, Francesca; Rivera, Andrea; Donega, Vanessa; Cantù, Claudio; Williams, Gareth; Berninger, Benedikt; Butt, Arthur M; Raineteau, Olivier

2017-03-01

Strategies for promoting neural regeneration are hindered by the difficulty of manipulating desired neural fates in the brain without complex genetic methods. The subventricular zone (SVZ) is the largest germinal zone of the forebrain and is responsible for the lifelong generation of interneuron subtypes and oligodendrocytes. Here, we have performed a bioinformatics analysis of the transcriptome of dorsal and lateral SVZ in early postnatal mice, including neural stem cells (NSCs) and their immediate progenies, which generate distinct neural lineages. We identified multiple signaling pathways that trigger distinct downstream transcriptional networks to regulate the diversity of neural cells originating from the SVZ. Next, we used a novel in silico genomic analysis, searchable platform-independent expression database/connectivity map (SPIED/CMAP), to generate a catalogue of small molecules that can be used to manipulate SVZ microdomain-specific lineages. Finally, we demonstrate that compounds identified in this analysis promote the generation of specific cell lineages from NSCs in vivo, during postnatal life and adulthood, as well as in regenerative contexts. This study unravels new strategies for using small bioactive molecules to direct germinal activity in the SVZ, which has therapeutic potential in neurodegenerative diseases.

Myxobolus arcticus and Parvicapsula minibicornis infections in sockeye salmon Oncorhynchus nerka following downstream migration in British Columbia.

PubMed

Mahony, A M; Johnson, S C; Neville, C M; Thiess, M E; Jones, S R M

2017-10-18

Factors influencing the health of sockeye salmon Oncorhynchus nerka in British Columbia, Canada, are important for fisheries management and conservation. Juvenile salmon originating from the Fraser River were screened for 3 enzootic parasites (Myxobolus arcticus, Parvicapsula minibicornis, Ceratonova shasta) and the bacterium Renibacterium salmoninarum. Fish were collected from the Strait of Georgia in 2010, 2011 and 2012 and genotyped to stock of origin. Trends in infection status were estimated by year, spawning zone and catch area. The annual prevalences of P. minibicornis (n = 1448) were 23.3, 6.5 and 8.1%, and for M. arcticus (n = 1343), annual prevalences were 40.4, 66.3 and 27.4%, respectively. Logistic regression showed that P. minibicornis was most strongly associated with salmon from the lower Fraser River spawning zone and increased with distance caught from the mouth of the Fraser River. In contrast, infection with M. arcticus was most strongly associated with salmon from the middle Fraser River spawning zone, and there was no trend related to distance from the Fraser River. Neither R. salmoninarum nor C. shasta were detected. These observations are discussed in the context of salmon life history and pathogen biology.

Sr-90 Immobilization by Infiltration of a Ca-Citrate-PO4 Solution into the Hanford 100-N Area Vadose Zone

DOE Office of Scientific and Technical Information (OSTI.GOV)

Szecsody, Jim E.; Fruchter, Jonathan S.; Burns, Carolyn A.

This project was initiated to develop a strategy for infiltration of a Ca-citrate-PO4 solution in order to precipitate apatite [Ca6(PO4)10(OH)2] in desired locations in the vadose zone for Sr-90 remediation. Laboratory experiments have demonstrated that infiltration of a Ca-citrate-PO4 solution into sediments at low and high water saturation results in citrate biodegradation and formation of apatite. The citrate biodegradation rate was relatively uniform, in spite of the spatial variability of sediment microbial biomass, likely because of microbial transport processes that occur during solution infiltration. The precipitate was characterized as hydroxyapatite, and the Sr-90 substitution into apatite was shown to havemore » a half-life of 5.5 to 16 months. 1-D and 2-D laboratory infiltration experiments quantified the spatial distribution of apatite that formed during solution infiltration. Slow infiltration in 2-D experiments at low water saturation show the apatite precipitate concentrated in the upper third of the infiltration zone. More rapid 1-D infiltration studies show the apatite precipitate concentrated at greater depth.« less

Life on the boundary: Environmental factors as drivers of habitat distribution in the littoral zone

NASA Astrophysics Data System (ADS)

Cefalì, Maria Elena; Cebrian, Emma; Chappuis, Eglantine; Pinedo, Susana; Terradas, Marc; Mariani, Simone; Ballesteros, Enric

2016-04-01

The boundary between land and sea, i.e. the littoral zone, is home to a large number of habitats whose distribution is primarily driven by the distance to the sea level but also by other environmental factors such as littoral's geomorphological features, wave exposure, water temperature or orientation. Here we explore the relative importance of those major environmental factors that drive the presence of littoral rocky habitats along 1100 Km of Catalonia's shoreline (Spain, NW Mediterranean) by using Geographic Information Systems and Generalized Linear Models. The distribution of mediolittoral and upper infralittoral habitats responded to different environmental factors. Mediolittoral habitats showed regional differences drawn by sea-water temperature and substrate type. Wave exposure (hydrodynamism), slope and geological features were only relevant to those mediolittoral habitats with specific environmental needs. We did not find any regional pattern of distribution in upper infralittoral habitats, and selected factors only played a moderate role in habitat distribution at the local scale. This study shows for the first time that environmental factors determining habitat distribution differ within the mediolittoral and the upper infralittoral zones and provides the basis for further development of models oriented at predicting the distribution of littoral marine habitats.

Prevalence and distribution of odontogenic cysts in a Mexican sample. A 753 cases study

PubMed Central

Villasis-Sarmiento, Luis; Melendez-Ocampo, Arcelia; Gaitan-Cepeda, Luis-Alberto; Leyva-Huerta, Elba-Rosa

2017-01-01

Background Odontogenic cysts (OC) are the most frequent lesions of the jaws and their constant epidemiological update is necessary and indispensable. Therefore the principal objective of this report was To determine prevalence and clinical-demographical characteristics of OC in a Mexican sample. Material and Methods 753 cases of OC coming from the archive of a head and neck histopathological teaching service, from January 2000 to December 2013, were included. OC cases were re-assessed according 2005 WHO classification. Chi square test was used to establish possible associations (p<0.05IC95%). Results From 753 OC, 369 were female and 384 male; 52.9% of them were in their 2nd- 4th decade of life. The most common location (41%) was the mandibular posterior area. Radicular cysts were more frequent in maxillary anterior zone of females (p 0.0002) at their fourth decade of life. Dentigerous cysts were more frequent in the mandibular posterior zone of males (p 0.0000) in their second decade of life. Six cases of periodontal lateral cyst; 4 cases of paradental cysts; 4 eruption cysts and 4 cases of adult gingival cyst, as well were identified. Conclusions Radicular cyst and dentigerous cyst are the most prevalent odontogenic cyst in this Mexican sample. Due to their etiology, dental pulpar necrosis and impacted teeth, radicular cyst and dentigerous cyst could be prevenible. Therefore, it is necessary to establish preventive strategies to diminish dental decay and programs of prophylactic extractions of impacted teeth, to in consequence decrease the prevalence of odontogenic cysts. Key words:Cyst, dentigerous cyst, mexican, odontogenic cyst, radicular cyst. PMID:28469818

Frost resistance in alpine woody plants.

PubMed

Neuner, Gilbert

2014-01-01

This report provides a brief review of key findings related to frost resistance in alpine woody plant species, summarizes data on their frost resistance, highlights the importance of freeze avoidance mechanisms, and indicates areas of future research. Freezing temperatures are possible throughout the whole growing period in the alpine life zone. Frost severity, comprised of both intensity and duration, becomes greater with increasing elevation and, there is also a greater probability, that small statured woody plants, may be insulated by snow cover. Several frost survival mechanisms have evolved in woody alpine plants in response to these environmental conditions. Examples of tolerance to extracellular freezing and freeze dehydration, life cycles that allow species to escape frost, and freeze avoidance mechanisms can all be found. Despite their specific adaption to the alpine environment, frost damage can occur in spring, while all alpine woody plants have a low risk of frost damage in winter. Experimental evidence indicates that premature deacclimation in Pinus cembra in the spring, and a limited ability of many species of alpine woody shrubs to rapidly reacclimate when they lose snow cover, resulting in reduced levels of frost resistance in the spring, may be particularly critical under the projected changes in climate. In this review, frost resistance and specific frost survival mechanisms of different organs (leaves, stems, vegetative and reproductive over-wintering buds, flowers, and fruits) and tissues are compared. The seasonal dynamics of frost resistance of leaves of trees, as opposed to woody shrubs, is also discussed. The ability of some tissues and organs to avoid freezing by supercooling, as visualized by high resolution infrared thermography, are also provided. Collectively, the report provides a review of the complex and diverse ways that woody plants survive in the frost dominated environment of the alpine life zone.

Food intake diet and sperm characteristics in a blue zone: a Loma Linda Study.

PubMed

Orzylowska, Eliza M; Jacobson, John D; Bareh, Gihan M; Ko, Edmund Y; Corselli, Johannah U; Chan, Philip J

2016-08-01

The study examined the effect the life-long vegetarian diet on male fertility and focused on vegetarians living in the Loma Linda blue zone, a demographic area known for life longevity. The objective was to compare sperm characteristics of vegetarian with non-vegetarian males. The cross-sectional observational study was based on semen analyses of 474 males from 2009 to 2013. Patients categorized themselves as either life-long lacto-ovo vegetarians (N=26; vegetable diet with dairy and egg products), vegans (N=5; strictly vegetables with no animal products) or non-vegetarians (N=443; no diet restrictions). Sperm quality was assessed using a computer-aided sperm analyzer and strict morphology and chromatin integrity were manually evaluated. Lacto-ovo vegetarians had lower sperm concentration (50.7±7.4M/mL versus non-vegetarians 69.6±3.2M/mL, mean±S.E.M.). Total motility was lower in the lacto-ovo and vegan groups (33.2±3.8% and 51.8±13.4% respectively) versus non-vegetarians (58.2±1.0%). Vegans had lowest hyperactive motility (0.8±0.7% versus lacto-ovo 5.2±1.2 and non-vegetarians 4.8±0.3%). Sperm strict morphologies were similar for the 3 groups. There were no differences in rapid progression and chromatin integrity. The study showed that the vegetables-based food intake decreased sperm quality. In particular, a reduction in sperm quality in male factor patients would be clinically significant and would require review. Furthermore, inadequate sperm hyperactivation in vegans suggested compromised membrane calcium selective channels. However, the study results are cautiously interpreted and more corroborative studies are needed. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Frost resistance in alpine woody plants

PubMed Central

Neuner, Gilbert

2014-01-01

This report provides a brief review of key findings related to frost resistance in alpine woody plant species, summarizes data on their frost resistance, highlights the importance of freeze avoidance mechanisms, and indicates areas of future research. Freezing temperatures are possible throughout the whole growing period in the alpine life zone. Frost severity, comprised of both intensity and duration, becomes greater with increasing elevation and, there is also a greater probability, that small statured woody plants, may be insulated by snow cover. Several frost survival mechanisms have evolved in woody alpine plants in response to these environmental conditions. Examples of tolerance to extracellular freezing and freeze dehydration, life cycles that allow species to escape frost, and freeze avoidance mechanisms can all be found. Despite their specific adaption to the alpine environment, frost damage can occur in spring, while all alpine woody plants have a low risk of frost damage in winter. Experimental evidence indicates that premature deacclimation in Pinus cembra in the spring, and a limited ability of many species of alpine woody shrubs to rapidly reacclimate when they lose snow cover, resulting in reduced levels of frost resistance in the spring, may be particularly critical under the projected changes in climate. In this review, frost resistance and specific frost survival mechanisms of different organs (leaves, stems, vegetative and reproductive over-wintering buds, flowers, and fruits) and tissues are compared. The seasonal dynamics of frost resistance of leaves of trees, as opposed to woody shrubs, is also discussed. The ability of some tissues and organs to avoid freezing by supercooling, as visualized by high resolution infrared thermography, are also provided. Collectively, the report provides a review of the complex and diverse ways that woody plants survive in the frost dominated environment of the alpine life zone. PMID:25520725

Density effect on great tit (Parus major) clutch size intensifies in a polluted environment.

PubMed

Eeva, Tapio; Lehikoinen, Esa

2013-12-01

Long-term data on a great tit (Parus major) population breeding in a metal-polluted zone around a copper-nickel smelter indicate that, against expectations, the clutch size of this species is decreasing even though metal emissions in the area have decreased considerably over the past two decades. Here, we document long-term population-level changes in the clutch size of P. major and explore if changes in population density, population numbers of competing species, timing of breeding, breeding habitat, or female age distribution can explain decreasing clutch sizes. Clutch size of P. major decreased by one egg in the polluted zone during the past 21 years, while there was no significant change in clutch size in the unpolluted reference zone over this time period. Density of P. major nests was similar in both environments but increased threefold during the study period in both areas (from 0.8 to 2.4 nest/ha). In the polluted zone, clutch size has decreased as a response to a considerable increase in population density, while a corresponding density change in the unpolluted zone did not have such an effect. The other factors studied did not explain the clutch size trend. Fledgling numbers in the polluted environment have been relatively low since the beginning of the study period, and they do not show a corresponding decrease to that noted for the clutch size over the same time period. Our study shows that responses of commonly measured life-history parameters to anthropogenic pollution depend on the structure of the breeding population. Interactions between pollution and intrinsic population characters should therefore be taken into account in environmental studies.

The effects of chronic alcoholism on cell proliferation in the human brain.

PubMed

Sutherland, G T; Sheahan, P J; Matthews, J; Dennis, C V P; Sheedy, D S; McCrossin, T; Curtis, M A; Kril, J J

2013-09-01

Neurogenesis continues in the human subventricular zone and to a lesser extent in the hippocampal subgranular zone throughout life. Subventricular zone-derived neuroblasts migrate to the olfactory bulb where survivors become integrated as interneurons and are postulated to contribute to odor discrimination. Adult neurogenesis is dysregulated in many neurological, neurovascular and neurodegenerative diseases. Alcohol abuse can result in a neurodegenerative condition called alcohol-related brain damage. Alcohol-related brain damage manifests clinically as cognitive dysfunction and the loss of smell sensation (hyposmia) and pathologically as generalized white matter atrophy and focal neuronal loss. The exact mechanism linking chronic alcohol intoxication with alcohol-related brain damage remains largely unknown but rodent models suggest that decreased neurogenesis is an important component. We investigated this idea by comparing proliferative events in the subventricular zone and olfactory bulb of a well-characterized cohort of 15 chronic alcoholics and 16 age-matched controls. In contrast to the findings in animal models there was no difference in the number of proliferative cell nuclear antigen-positive cells in the subventricular zone of alcoholics (mean±SD=28.7±20.0) and controls (27.6±18.9, p=1.0). There were also no differences in either the total (p=0.89) or proliferative cells (p=0.98) in the granular cell layer of the olfactory bulb. Our findings show that chronic alcohol consumption does not affect cell proliferation in the human SVZ or olfactory bulb. In fact only microglial proliferation could be demonstrated in the latter. Therefore neurogenic deficits are unlikely to contribute to hyposmia in chronic alcoholics. Copyright © 2013 Elsevier Inc. All rights reserved.

The Importance of Water for Life

NASA Astrophysics Data System (ADS)

Westall, Frances; Brack, André

2018-03-01

Liquid water is essential for life as we know it, i.e. carbon-based life. Although other compound-solvent pairs that could exist in very specific physical environments could be envisaged, the elements essential to carbon and water-based life are among the most common in the universe. Carbon molecules and liquid water have physical and chemical properties that make them optimised compound-solvent pairs. Liquid water is essential for important prebiotic reactions. But equally important for the emergence of life is the contact of carbon molecules in liquid water with hot rocks and minerals. We here review the environmental conditions of the early Earth, as soon as it had liquid water at its surface and was habitable. Basing our approach to life as a "cosmic phenomenon" (de Duve 1995), i.e. a chemical continuum, we briefly address the various hypotheses for the origin of life, noting their relevance with respect to early environmental conditions. It appears that hydrothermal environments were important in this respect. We continue with the record of early life noting that, by 3.5 Ga, when the sedimentary environment started being well-preserved, anaerobic life forms had colonised all habitable microenvironments from the sea floor to exposed beach environments and, possibly, in the photic planktonic zone of the sea. Life on Earth had also evolved to the relatively sophisticated stage of anoxygenic photosynthesis. We conclude with an evaluation of the potential for habitability and colonisation of other planets and satellites in the Solar System, noting that the most common life forms in the Solar System and probably in the Universe would be similar to terrestrial chemotrophs whose carbon source is either reduced carbon or CO2 dissolved in water and whose energy would be sourced from oxidized carbon, H2, or other transition elements.

Surface biosignatures of exo-earths: remote detection of extraterrestrial life.

PubMed

Hegde, Siddharth; Paulino-Lima, Ivan G; Kent, Ryan; Kaltenegger, Lisa; Rothschild, Lynn

2015-03-31

Exoplanet discovery has made remarkable progress, with the first rocky planets having been detected in the central star's liquid water habitable zone. The remote sensing techniques used to characterize such planets for potential habitability and life rely solely on our understanding of life on Earth. The vegetation red edge from terrestrial land plants is often used as a direct signature of life, but it occupies only a small niche in the environmental parameter space that binds life on present-day Earth and has been widespread for only about 460 My. To more fully exploit the diversity of the one example of life known, we measured the spectral characteristics of 137 microorganisms containing a range of pigments, including ones isolated from Earth's most extreme environments. Our database covers the visible and near-infrared to the short-wavelength infrared (0.35-2.5 µm) portions of the electromagnetic spectrum and is made freely available from biosignatures.astro.cornell.edu. Our results show how the reflectance properties are dominated by the absorption of light by pigments in the visible portion and by strong absorptions by the cellular water of hydration in the infrared (up to 2.5 µm) portion of the spectrum. Our spectral library provides a broader and more realistic guide based on Earth life for the search for surface features of extraterrestrial life. The library, when used as inputs for modeling disk-integrated spectra of exoplanets, in preparation for the next generation of space- and ground-based instruments, will increase the chances of detecting life.

Surface biosignatures of exo-Earths: Remote detection of extraterrestrial life

PubMed Central

Hegde, Siddharth; Paulino-Lima, Ivan G.; Kent, Ryan; Kaltenegger, Lisa; Rothschild, Lynn

2015-01-01

Exoplanet discovery has made remarkable progress, with the first rocky planets having been detected in the central star’s liquid water habitable zone. The remote sensing techniques used to characterize such planets for potential habitability and life rely solely on our understanding of life on Earth. The vegetation red edge from terrestrial land plants is often used as a direct signature of life, but it occupies only a small niche in the environmental parameter space that binds life on present-day Earth and has been widespread for only about 460 My. To more fully exploit the diversity of the one example of life known, we measured the spectral characteristics of 137 microorganisms containing a range of pigments, including ones isolated from Earth’s most extreme environments. Our database covers the visible and near-infrared to the short-wavelength infrared (0.35–2.5 µm) portions of the electromagnetic spectrum and is made freely available from biosignatures.astro.cornell.edu. Our results show how the reflectance properties are dominated by the absorption of light by pigments in the visible portion and by strong absorptions by the cellular water of hydration in the infrared (up to 2.5 µm) portion of the spectrum. Our spectral library provides a broader and more realistic guide based on Earth life for the search for surface features of extraterrestrial life. The library, when used as inputs for modeling disk-integrated spectra of exoplanets, in preparation for the next generation of space- and ground-based instruments, will increase the chances of detecting life. PMID:25775594

Spatial variability and long-term analysis of groundwater quality of Faisalabad industrial zone

NASA Astrophysics Data System (ADS)

Nasir, Muhammad Salman; Nasir, Abdul; Rashid, Haroon; Shah, Syed Hamid Hussain

2017-10-01

Water is the basic necessity of life and is essential for healthy society. In this study, groundwater quality analysis was carried out for the industrial zone of Faisalabad city. Sixty samples of groundwater were collected from the study area. The quality maps of deliberately analyzed results were prepared in GIS. The collected samples were analyzed for chemical parameters and heavy metals, such as total hardness, alkalinity, cadmium, arsenic, nickel, lead, and fluoride, and then, the results were compared with the WHO guidelines. The values of these results were represented by a mapping of quality parameters using the ArcView GIS v9.3, and IDW was used for raster interpolation. The long-term analysis of these parameters has been carried out using the `R Statistical' software. It was concluded that water is partially not fit for drinking, and direct use of this groundwater may cause health issues.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Walsh, David A.; Zaikova, Elena; Howes, Charles L.

Oxygen minimum zones (OMZs), also known as oceanic"dead zones", are widespread oceanographic features currently expanding due to global warming and coastal eutrophication. Although inhospitable to metazoan life, OMZs support a thriving but cryptic microbiota whose combined metabolic activity is intimately connected to nutrient and trace gas cycling within the global ocean. Here we report time-resolved metagenomic analyses of a ubiquitous and abundant but uncultivated OMZ microbe (SUP05) closely related to chemoautotrophic gill symbionts of deep-sea clams and mussels. The SUP05 metagenome harbors a versatile repertoire of genes mediating autotrophic carbon assimilation, sulfur-oxidation and nitrate respiration responsive to a wide rangemore » of water column redox states. Thus, SUP05 plays integral roles in shaping nutrient and energy flow within oxygen-deficient oceanic waters via carbon sequestration, sulfide detoxification and biological nitrogen loss with important implications for marine productivity and atmospheric greenhouse control.« less

Ocean acidification in the coastal zone from an organism's perspective: multiple system parameters, frequency domains, and habitats.

PubMed

Waldbusser, George G; Salisbury, Joseph E

2014-01-01

Multiple natural and anthropogenic processes alter the carbonate chemistry of the coastal zone in ways that either exacerbate or mitigate ocean acidification effects. Freshwater inputs and multiple acid-base reactions change carbonate chemistry conditions, sometimes synergistically. The shallow nature of these systems results in strong benthic-pelagic coupling, and marine invertebrates at different life history stages rely on both benthic and pelagic habitats. Carbonate chemistry in coastal systems can be highly variable, responding to processes with temporal modes ranging from seconds to centuries. Identifying scales of variability relevant to levels of biological organization requires a fuller characterization of both the frequency and magnitude domains of processes contributing to or reducing acidification in pelagic and benthic habitats. We review the processes that contribute to coastal acidification with attention to timescales of variability and habitats relevant to marine bivalves.

Organic contamination of surface sediments in the metropolitan coastal zone of Athens, Greece: sources, degree, and ecological risk.

PubMed

Kapsimalis, V; Panagiotopoulos, I P; Talagani, P; Hatzianestis, I; Kaberi, H; Rousakis, G; Kanellopoulos, T D; Hatiris, G A

2014-03-15

Bottom sediments represent a crucial component of the marine environment, since they constitute a habitat, a trophic resource, and a spawning place for various organisms. Unfortunately, the sediments of urban coastal areas are deeply impacted by anthropogenic activities that degrade their quality. In the Drapetsona-Keratsini metropolitan coastal zone of Athens, current industrial and shipping activities together with the effluents from a sewage outfall, which was in operation in the past, have resulted in one of the most contaminated sedimentary environments, in terms of organic compound loads, in Mediterranean. Exceptionally high concentrations of aliphatic hydrocarbons (up to 4457 μg g⁻¹), carcinogenic PAHs (up to 7284 ng g⁻¹), and organochlorines (up to 544 ng g⁻¹ for PCBs; up to 208 ng g⁻¹ for DDTs) constitute a major threat to the marine life of the associated Saronikos Gulf. Copyright © 2013 Elsevier Ltd. All rights reserved.

Stakeholder Analysis in Utilizing of Environmental Services and Natural Attractions in Tuk Semuncar Utilization Zone of Gunung Merbabu National Park: A literature review

NASA Astrophysics Data System (ADS)

Setiawan, Muhammad Arif; Muhammad, Fuad

2018-02-01

Many stakeholders in the utilizing of environmental services and natural attraction of Tuk Semuncar Utilization Zone needs to get the attention of the Gunung Merbabu National Park Officer. The existence of natural resources has an important role for the life of the community, making the complexity of the relationship between various parties who have interests in natural resource management. The existence of stakeholders and their interests should receive attention and be considered to be accommodated as an effort to prevent the occurrence of losses to the conservation area of Gunung Merbabu National Park. Every stakeholder's interest can have a positive and negative impact on other stakeholders. Stakeholder analysis can help in understanding the conflict on the utilizing of environmental services and natural attraction that is happening, as well as input strategy in involving stakeholders for the achievement of goals.

An Earth-mass planet orbiting α Centauri B.

PubMed

Dumusque, Xavier; Pepe, Francesco; Lovis, Christophe; Ségransan, Damien; Sahlmann, Johannes; Benz, Willy; Bouchy, François; Mayor, Michel; Queloz, Didier; Santos, Nuno; Udry, Stéphane

2012-11-08

Exoplanets down to the size of Earth have been found, but not in the habitable zone--that is, at a distance from the parent star at which water, if present, would be liquid. There are planets in the habitable zone of stars cooler than our Sun, but for reasons such as tidal locking and strong stellar activity, they are unlikely to harbour water-carbon life as we know it. The detection of a habitable Earth-mass planet orbiting a star similar to our Sun is extremely difficult, because such a signal is overwhelmed by stellar perturbations. Here we report the detection of an Earth-mass planet orbiting our neighbour star α Centauri B, a member of the closest stellar system to the Sun. The planet has an orbital period of 3.236 days and is about 0.04 astronomical units from the star (one astronomical unit is the Earth-Sun distance).

Littoral foraging by red phalaropes during spring in the northern Bering Sea

USGS Publications Warehouse

Haney, J. Christopher; Stone, Amy E.

1988-01-01

Phalaropes demonstrate considerable plasticity in their choice of foraging habitats. The Red Phalarope (Phalaropus fulicaria) alternates use of pelagic environments in winter and migration (Taning 1933, Stanford 1953, Briggs et al 1984) with wet tundra habitats during the breeding season (Kistchinski 1975, Mayfield 1979, Ridley 1980). Foods available and taken in littoral zones of the Arctic Ocean in fall have been identified (Conners and Risebrough 1978, Johnson and Richardson 1980), but otherwise little attention has been devoted to the transition between the marine and terrestrial periods of the Red Phalarope’s life history. We report phalarope use of littoral areas during spring in the northern Bering Sea and Kongkok Bay, St. Lawrence Island, Alaska. In addition, we describe phalarope foraging tactics and foods available in the sur zone, emphasizing this form of littoral foraging as an opportunistic and facultative feeding strategy.

Regulation of nitrogen uptake and assimilation: Effects of nitrogen source, root-zone pH, and aerial CO2 concentration on growth and productivity of soybeans

NASA Technical Reports Server (NTRS)

Raper, C. D.; Tolley-Henry, L.

1989-01-01

An important feature of controlled-environment crop production systems such as those to be used for life support of crews during space exploration is the efficient utilization of nitrogen supplies. Making decisions about the best sources of these supplies requires research into the relationship between nitrogen source and the physiological processes which regulate vegetative and reproductive plant growth. Work done in four areas within this research objective is reported: (1) experiments on the effects of root-zone pH on preferential utilization of NO3(-) versus NH4(+) nitrogen; (2) investigation of processes at the whole-plant level that regulate nitrogen uptake; (3) studies of the effects of atmospheric CO2 and NO3(-) supply on the growth of soybeans; and (4) examination of the role of NO3(-) uptake in enhancement of root respiration.

The utilization of the microflora indigenous to and present in oil-bearing formations to selectively plug the more porous zones thereby increasing oil recovery during waterflooding, Class 1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stephens, James O.; Brown, Lewis R.; Vadie, A. Alex

2000-02-02

The objectives of this project were (1) to demonstrate the in situ microbial population in a fluvial dominated deltaic reservoir could be induced to proliferate to such an extent that they will selectively restrict flow in the more porous zones in the reservoir thereby forcing injection water to flow through previously unswept areas thus improving the sweep efficiency of the waterflood and (2) to obtain scientific validation that microorganisms are indeed responsible for the increased oil recovery. One expected outcome of this new technology was the prolongation of economical life of the reservoir, i.e. economical oil recovery should continue formore » much longer periods in areas of the reservoir subjected to the MPPM technology than it would if it followed its historic trend.« less

Transformation of temporal sequences in the zebra finch auditory system

PubMed Central

Lim, Yoonseob; Lagoy, Ryan; Shinn-Cunningham, Barbara G; Gardner, Timothy J

2016-01-01

This study examines how temporally patterned stimuli are transformed as they propagate from primary to secondary zones in the thalamorecipient auditory pallium in zebra finches. Using a new class of synthetic click stimuli, we find a robust mapping from temporal sequences in the primary zone to distinct population vectors in secondary auditory areas. We tested whether songbirds could discriminate synthetic click sequences in an operant setup and found that a robust behavioral discrimination is present for click sequences composed of intervals ranging from 11 ms to 40 ms, but breaks down for stimuli composed of longer inter-click intervals. This work suggests that the analog of the songbird auditory cortex transforms temporal patterns to sequence-selective population responses or ‘spatial codes', and that these distinct population responses contribute to behavioral discrimination of temporally complex sounds. DOI: http://dx.doi.org/10.7554/eLife.18205.001 PMID:27897971

Mathematical modeling of ignition of woodlands resulted from accident on the pipeline

NASA Astrophysics Data System (ADS)

Perminov, V. A.; Loboda, E. L.; Reyno, V. V.

2014-11-01

Accidents occurring at the sites of pipelines, accompanied by environmental damage, economic loss, and sometimes loss of life. In this paper we calculated the sizes of the possible ignition zones in emergency situations on pipelines located close to the forest, accompanied by the appearance of fireballs. In this paper, using the method of mathematical modeling calculates the maximum size of the ignition zones of vegetation as a result of accidental releases of flammable substances. The paper suggested in the context of the general mathematical model of forest fires give a new mathematical setting and method of numerical solution of a problem of a forest fire modeling. The boundary-value problem is solved numerically using the method of splitting according to physical processes. The dependences of the size of the forest fuel for different amounts of leaked flammable substances and moisture content of vegetation.

Assessing dorsal scute microchemistry for reconstruction of shortnose sturgeon life histories

USGS Publications Warehouse

Altenritter, Matthew E.; Kinnison, Michael T.; Zydlewski, Gayle B.; Secor, David H.; Zydlewski, Joseph D.

2015-01-01

The imperiled status of sturgeons worldwide places priority on the identification and protection of critical habitats. We assessed the micro-structural and micro-chemical scope for a novel calcified structure, dorsal scutes, to be used for reconstruction of past habitat use and group separation in shortnose sturgeon (Acipenser brevirostrum). Dorsal scutes contained a dual-layered structure composed of a thin multi-layered translucent zone lying dorsally above a thicker multi-layered zone. Banding in the thick multi-layered zone correlated strongly with pectoral fin spine annuli supporting the presence of chronological structuring that could contain a chemical record of past environmental exposure. Trace element profiles (Sr:Ca), collected using both wavelength dispersive electron microprobe analysis and laser ablation inductively coupled mass spectrometry, suggest scutes record elemental information useful for tracing transitions between freshwater and marine environments. Moreover, mirror-image like Sr:Ca profiles were observed across the dual-zone structuring of the scute that may indicate duplication of the microchemical profile in a single structure. Additional element:calcium ratios measured in natal regions of dorsal scutes (Ba:Ca, Mg:Ca) suggest the potential for further refinement of techniques for identification of river systems of natal origin. In combination, our results provide proof of concept that dorsal scutes possess the necessary properties to be used as structures for reconstructions of past habitat use in sturgeons. Importantly, scutes may be collected non-lethally and with less injury than current structures, like otoliths and fin spines, affording an opportunity for broader application of microchemical techniques.

Microvascular reconstructive surgery in Operations Iraqi and Enduring Freedom: the US military experience performing free flaps in a combat zone.

PubMed

Klem, Christopher; Sniezek, Joseph C; Moore, Brian; Davis, Michael R; Coppit, George; Schmalbach, Cecelia

2013-08-01

Local nationals with complex wounds resulting from traumatic combat injuries during Operations Iraqi Freedom and Enduring Freedom usually must undergo reconstructive surgery in the combat zone. While the use of microvascular free-tissue transfer (free flaps) for traumatic reconstruction is well documented in the literature, various complicating factors exist when these intricate surgical procedures are performed in a theater of war. The microvascular experiences of six military surgeons deployed during a 30-month period between 2006 and 2011 in Iraq and Afghanistan were retrospectively reviewed. Twenty-nine patients presented with complex traumatic wounds. Thirty-one free flaps were performed for the 29 patients. Location of tissue defects included the lower extremity (15), face/neck (8), upper extremity (6). Limb salvage was successful in all but one patient. Six of eight patients with head and neck wounds were tolerating oral intake at the time of discharge. There were three flap losses in 3 patients; two patients who experienced flap loss underwent a successful second free or regional flap. Minor complications occurred in six patients. Microvascular free tissue transfer for complex tissue defects in a combat zone is a critically important task and can improve quality of life for host-nation patients. Major US combat hospitals deployed to a war zone should include personnel who are trained and capable of performing these complex reconstructive procedures and who understand the many nuances of optimizing outcomes in this challenging environment.

LED-driven backlights for automotive displays

NASA Astrophysics Data System (ADS)

Strauch, Frank

2007-09-01

As a light source the LED has some advantage over the traditionally used fluorescence tube such as longer life or lower space consumption. Consequently customers are asking for the LED lighting design in their products. We introduced in a company owned backlight the white LED technology. This step opens the possibility to have access to the components in the display market. Instead of having a finalized display product which needs to be integrated in the head unit of a car we assemble the backlight, the glass, own electronics and the housing. A major advantage of this concept is the better control of the heat flow generated by the LEDs to the outer side because only a common housing is used for all the components. Also the requirement for slim products can be fulfilled. As always a new technology doesn't come with advantages only. An LED represents a point source compared to the well-known tube thus requiring a mixing zone for the multiple point sources when they enter a light guide. This zone can't be used in displays because of the lack of homogeneity. It's a design goal to minimize this zone which can be helped by the right choice of the LED in terms of slimness. A step ahead is the implementation of RGB LEDs because of their higher color rendering abilities. This allows for the control of the chromaticity point under temperature change but as a drawback needs a larger mixing zone.

A Comparison between Temperature-Controlled Laminar Airflow Device and a Room Air-Cleaner in Reducing Exposure to Particles While Asleep

PubMed Central

Spilak, Michal P.; Sigsgaard, Torben; Takai, Hisamitsu; Zhang, Guoqiang

2016-01-01

People spend approximately one third of their life sleeping. Exposure to pollutants in the sleep environment often leads to a variety of adverse health effects, such as development and exacerbation of asthma. Avoiding exposure to these pollutants by providing a sufficient air quality in the sleep environment might be a feasible method to alleviate these health symptoms. We performed full-scale laboratory measurements using a thermal manikin positioned on an experimental bed. Three ventilation settings were tested: with no filtration system operated, use of portable air cleaner and use of a temperature-controlled laminar airflow (TLA) device. The first part of the experiment investigated the air-flow characteristics in the breathing zone. In the second part, particle removal efficiency was estimated. Measured in the breathing zone, the room air cleaner demonstrated high turbulence intensity, high velocity and turbulence diffusivity level, with a particle reduction rate of 52% compared to baseline after 30 minutes. The TLA device delivered a laminar airflow to the breathing zone with a reduction rate of 99.5%. During a periodical duvet lifting mimicking a subject’s movement in bed, the particle concentration was significantly lower with the TLA device compared to the room air cleaner. The TLA device provided a barrier which significantly reduced the introduction of airborne particles into the breathing zone. Further studies should be conducted for the understanding of the transport of resuspended particles between the duvet and the laying body. PMID:27898693

A Comparison between Temperature-Controlled Laminar Airflow Device and a Room Air-Cleaner in Reducing Exposure to Particles While Asleep.

PubMed

Spilak, Michal P; Sigsgaard, Torben; Takai, Hisamitsu; Zhang, Guoqiang

2016-01-01

People spend approximately one third of their life sleeping. Exposure to pollutants in the sleep environment often leads to a variety of adverse health effects, such as development and exacerbation of asthma. Avoiding exposure to these pollutants by providing a sufficient air quality in the sleep environment might be a feasible method to alleviate these health symptoms. We performed full-scale laboratory measurements using a thermal manikin positioned on an experimental bed. Three ventilation settings were tested: with no filtration system operated, use of portable air cleaner and use of a temperature-controlled laminar airflow (TLA) device. The first part of the experiment investigated the air-flow characteristics in the breathing zone. In the second part, particle removal efficiency was estimated. Measured in the breathing zone, the room air cleaner demonstrated high turbulence intensity, high velocity and turbulence diffusivity level, with a particle reduction rate of 52% compared to baseline after 30 minutes. The TLA device delivered a laminar airflow to the breathing zone with a reduction rate of 99.5%. During a periodical duvet lifting mimicking a subject's movement in bed, the particle concentration was significantly lower with the TLA device compared to the room air cleaner. The TLA device provided a barrier which significantly reduced the introduction of airborne particles into the breathing zone. Further studies should be conducted for the understanding of the transport of resuspended particles between the duvet and the laying body.

Climate change vulnerability to agrarian ecosystem of small Island: evidence from Sagar Island, India

NASA Astrophysics Data System (ADS)

Mandal, S.; Satpati, L. N.; Choudhury, B. U.; Sadhu, S.

2018-04-01

The present study assessed climate change vulnerability in agricultural sector of low-lying Sagar Island of Bay of Bengal. Vulnerability indices were estimated using spatially aggregated biophysical and socio-economic parameters by applying principal component analysis and equal weight method. The similarities and differences of outputs of these two methods were analysed across the island. From the integration of outputs and based on the severity of vulnerability, explicit vulnerable zones were demarcated spatially. Results revealed that life subsistence agriculture in 11.8% geographical area (2829 ha) of the island along the western coast falls under very high vulnerable zone (VHVZ VI of 84-99%) to climate change. Comparatively higher values of exposure (0.53 ± 0.26) and sensitivity (0.78 ± 0.14) subindices affirmed that the VHV zone is highly exposed to climate stressor with very low adaptive capacity (ADI= 0.24 ± 0.16) to combat vulnerability to climate change. Hence, food security for a population of >22 thousands comprising >3.7 thousand agrarian households are highly exposed to climate change. Another 17% area comprising 17.5% population covering 20% villages in north-western and eastern parts of the island also falls under high vulnerable (VI= 61%-77%) zone. Findings revealed large spatial heterogeneity in the degree of vulnerability across the island and thus, demands devising area specific planning (adaptation and mitigation strategies) to address the climate change impact implications both at macro and micro levels.

Impact of Dental Disorders and its Influence on Self Esteem Levels among Adolescents.

PubMed

Kaur, Puneet; Singh, Simarpreet; Mathur, Anmol; Makkar, Diljot Kaur; Aggarwal, Vikram Pal; Batra, Manu; Sharma, Anshika; Goyal, Nikita

2017-04-01

Self esteem is more of a psychological concept therefore, even the common dental disorders like dental trauma, tooth loss and untreated carious lesions may affect the self esteem thus influencing the quality of life. This study aims to assess the impact of dental disorders among the adolescents on their self esteem level. The present cross-sectional study was conducted among 10 to 17 years adolescents. In order to obtain a representative sample, multistage sampling technique was used and sample was selected based on Probability Proportional to Enrolment size (PPE). Oral health assessment was carried out using WHO type III examination and self esteem was estimated using the Rosenberg Self Esteem Scale score (RSES). The descriptive and inferential analysis of the data was done by using IBM SPSS software. Logistic and linear regression analysis was executed to test the individual association of different independent clinical variables with self esteem. Total sample of 1140 adolescents with mean age of 14.95 ±2.08 and RSES of 27.09 ±3.12 were considered. Stepwise multiple linear regression analysis was applied and best predictors in relation to RSES in the descending order were Dental Health Component (DHC), Aesthetic Component (AC), dental decay {(aesthetic zone), (masticatory zone)}, tooth loss {(aesthetic zone), (masticatory zone)} and anterior fracture of tooth. It was found that various dental disorders like malocclusion, anterior traumatic tooth, tooth loss and untreated decay causes a profound impact on aesthetics and psychosocial behaviour of adolescents, thus affecting their self esteem.

Analyzing the effect of cutting parameters on surface roughness and tool wear when machining nickel based hastelloy - 276

NASA Astrophysics Data System (ADS)

Khidhir, Basim A.; Mohamed, Bashir

2011-02-01

Machining parameters has an important factor on tool wear and surface finish, for that the manufacturers need to obtain optimal operating parameters with a minimum set of experiments as well as minimizing the simulations in order to reduce machining set up costs. The cutting speed is one of the most important cutting parameter to evaluate, it clearly most influences on one hand, tool life, tool stability, and cutting process quality, and on the other hand controls production flow. Due to more demanding manufacturing systems, the requirements for reliable technological information have increased. For a reliable analysis in cutting, the cutting zone (tip insert-workpiece-chip system) as the mechanics of cutting in this area are very complicated, the chip is formed in the shear plane (entrance the shear zone) and is shape in the sliding plane. The temperature contributed in the primary shear, chamfer and sticking, sliding zones are expressed as a function of unknown shear angle on the rake face and temperature modified flow stress in each zone. The experiments were carried out on a CNC lathe and surface finish and tool tip wear are measured in process. Machining experiments are conducted. Reasonable agreement is observed under turning with high depth of cut. Results of this research help to guide the design of new cutting tool materials and the studies on evaluation of machining parameters to further advance the productivity of nickel based alloy Hastelloy - 276 machining.

Assessment of spatial information for hyperspectral imaging of lesion

NASA Astrophysics Data System (ADS)

Yang, Xue; Li, Gang; Lin, Ling

2016-10-01

Multiple diseases such as breast tumor poses a great threat to women's health and life, while the traditional detection method is complex, costly and unsuitable for frequently self-examination, therefore, an inexpensive, convenient and efficient method for tumor self-inspection is needed urgently, and lesion localization is an important step. This paper proposes an self-examination method for positioning of a lesion. The method adopts transillumination to acquire the hyperspectral images and to assess the spatial information of lesion. Firstly, multi-wavelength sources are modulated with frequency division, which is advantageous to separate images of different wavelength, meanwhile, the source serves as fill light to each other to improve the sensitivity in the low-lightlevel imaging. Secondly, the signal-to-noise ratio of transmitted images after demodulation are improved by frame accumulation technology. Next, gray distributions of transmitted images are analyzed. The gray-level differences is constituted by the actual transmitted images and fitting transmitted images of tissue without lesion, which is to rule out individual differences. Due to scattering effect, there will be transition zones between tissue and lesion, and the zone changes with wavelength change, which will help to identify the structure details of lesion. Finally, image segmentation is adopted to extract the lesion and the transition zones, and the spatial features of lesion are confirmed according to the transition zones and the differences of transmitted light intensity distributions. Experiment using flat-shaped tissue as an example shows that the proposed method can extract the space information of lesion.

The interaction of fatigue cracks with a residual stress field using thermoelastic stress analysis and synchrotron X-ray diffraction experiments

PubMed Central

Amjad, Khurram; Asquith, David; Sebastian, Christopher M.; Wang, Wei-Chung

2017-01-01

This article presents an experimental study on the fatigue behaviour of cracks emanating from cold-expanded holes utilizing thermoelastic stress analysis (TSA) and synchrotron X-ray diffraction (SXRD) techniques with the aim of resolving the long-standing ambiguity in the literature regarding potential relaxation, or modification, of beneficial compressive residual stresses as a result of fatigue crack propagation. The crack growth rates are found to be substantially lower as the crack tip moved through the residual stress zone induced by cold expansion. The TSA results demonstrated that the crack tip plastic zones were reduced in size by the presence of the residual compressive stresses induced by cold expansion. The crack tip plastic zones were found to be insignificant in size in comparison to the residual stress zone resulting from cold expansion, which implied that they were unlikely to have had a notable impact on the surrounding residual stresses induced by cold expansion. The residual stress distributions measured along the direction of crack growth, using SXRD, showed no signs of any significant stress relaxation or redistribution, which validates the conclusions drawn from the TSA data. Fractographic analysis qualitatively confirmed the influence on crack initiation of the residual stresses induced by the cold expansion. It was found that the application of single compressive overload caused a relaxation, or reduction in the residual stresses, which has wider implications for improving the fatigue life. PMID:29291095

The effects of exposure in sandy beach surf zones on larval fishes.

PubMed

Pattrick, P; Strydom, N A

2014-05-01

The influence of wind and wave exposure on larval fish assemblages within a large bay system was investigated. Larval fishes were sampled from two areas with vastly different exposure to waves and wind, namely the windward and leeward sectors of Algoa Bay. In total, 5702 larval fishes were collected using a modified larval seine. Of these, 4391 were collected in the leeward and 1311 in the windward sector of the bay, representing a total of 23 families and 57 species. Dominant fish families included Clinidae, Engraulidae, Kyphosidae, Mugilidae, Soleidae and Sparidae, similar to the situation elsewhere, highlighting continuity in the composition of larval fish assemblages and the utilization of surf zones by a specific group of larval fishes. Nineteen estuary-associated marine species occurred within the surf zones of Algoa Bay and dominated catches (86·7%) in terms of abundance. Postflexion larvae comprised > 80% of the catch, indicating the importance of the seemingly inhospitable surf zone environment for the early life stages of many fish species. The greatest species diversity was observed within the windward sector of the bay. Distance-based linear modelling identified wave period as the environmental variable explaining the largest proportion of the significant variation in the larval fish assemblage. The physical disturbance generated by breaking waves could create a suitable environment for fish larvae, sheltered from predators and with an abundance of food resources. © 2014 The Fisheries Society of the British Isles.

OZCAR: the French network of Critical Zone Observatories: principles and scientific objectives

NASA Astrophysics Data System (ADS)

Braud, Isabelle; Gaillardet, Jérôme; Hankard, Fatim; Le Borgne, Tanguy; Nord, Guillaume; Six, Delphine; Galy, Catherine; Laggoun-Défarge, Fatima; Tallec, Tiphaine; Pauwels, Hélène

2017-04-01

This contribution aims at presenting the principles that underlined the creation of the OZCAR research infrastructure, gathering various Critical Zone Observatories in France, and the scientific questions that drives the observation settings. The Critical Zone includes the fine zone between the lower atmosphere at the top of the canopy down to the bedrock-soil interface. This lithosphere-atmosphere boundary is critical for the availability of life-sustaining resources and critical for humanity because this is the zone where we live, where we build our cities, from which we extract our food and our water and where we release most of our wastes. This is the fragile zone on which the natural ecosystem relies because this is where nutrients are being released from the rocks. OZCAR is a distributed research infrastructure gathering instrumented sites and catchments on continental surfaces all dedicated to the observation and monitoring of the different compartments of the Critical Zone at the national scale. All these observatories (more that 40) were all built up on specific questions (acid deposition, flood prediction, urban hydrology…), some of them more than 50 years ago, but they have all in common to be highly instrumented, permanently funded as infrastructures. They all share the same overarching goal of understanding and predicting the Critical Zone in a changing world. OZCAR gathers instrumented catchments, hydrogeological sites, peatlands, glacier and permafrost regions and a spatial observatory under the common umbrella of understanding water and biogeochemical cycles and the associated fluxes of energy by using natural gradients and experimentation. Based on the collaboration with Southern Countries, OZCAR's sites have a global coverage including tropical areas and high mountainous regions in the Andes and the Himalaya. OZCAR benefits from a French investments project called CRITEX (Innovative equipment for the critical zone, https://www.critex.fr/critex-3/observatories/ ) that is centered on the development and deployment of innovative instrumentation in the sites. OZCAR was launched in 2016 under the leadership of the French Ministry in charge of Higher Education and Research, assembling all French Research Institutions involved in environmental studies and with the ambition of facilitating interdisciplinary research in terrestrial surfaces, stimulating instrumental development and being visible at the international level. The paper will presents the main common scientific questions, challenges in terms of instrumentation and experimentation deployment, in particular in terms of co-location of sites, data base and modelling activities that the OZCAR network plan to address in the next years.

The Cerebellum, Sensitive Periods, and Autism

PubMed Central

Wang, Samuel S.-H.; Kloth, Alexander D.; Badura, Aleksandra

2014-01-01

Cerebellar research has focused principally on adult motor function. However, the cerebellum also maintains abundant connections with nonmotor brain regions throughout postnatal life. Here we review evidence that the cerebellum may guide the maturation of remote nonmotor neural circuitry and influence cognitive development, with a focus on its relationship with autism. Specific cerebellar zones influence neocortical substrates for social interaction, and we propose that sensitive-period disruption of such internal brain communication can account for autism's key features. PMID:25102558

A Safe Zone for Veterans: Developing the VET NET Ally Program to Increase Faculty and Staff Awareness and Sensitivity to the Needs of Military Veterans in Higher Education

ERIC Educational Resources Information Center

Thomas, Marshall W.

2010-01-01

Given the increased educational benefits of the Post 9/11 G. I. Bill for veterans, and as the current conflicts in Iraq and Afghanistan wind down and the troops come home, the number of military veterans entering colleges and universities is expected to increase. As non-traditional students with significant life experience, often including combat,…

Analysis on regulation strategies for extending service life of hydropower turbines

NASA Astrophysics Data System (ADS)

Yang, W.; Norrlund, P.; Yang, J.

2016-11-01

Since a few years, there has been a tendency that hydropower turbines experience fatigue to a greater extent, due to increasingly more regulation movements of governor actuators. The aim of this paper is to extend the service life of hydropower turbines, by reasonably decreasing the guide vane (GV) movements with appropriate regulation strategies, e.g. settings of PI (proportional-integral) governor parameters and controller filters. The accumulated distance and number of GV movements are the two main indicators of this study. The core method is to simulate the long-term GV opening of Francis turbines with MATLAB/Simulink, based on a sequence of one-month measurements of the Nordic grid frequency. Basic theoretical formulas are also discussed and compared to the simulation results, showing reasonable correspondence. Firstly, a model of a turbine governor is discussed and verified, based on on-site measurements of a Swedish hydropower plant. Then, the influence of governor parameters is discussed. Effects of different settings of controller filters (e.g. dead zone, floating dead zone and linear filter) are also examined. Moreover, a change in GV movement might affect the quality of the frequency control. This is also monitored via frequency deviation characteristics, determined by elementary simulations of the Nordic power system. The results show how the regulation settings affect the GV movements and frequency quality, supplying suggestions for optimizing the hydropower turbine operation for decreasing the wear and tear.

Possible impacts of ozone depletion on trophic interactions and biogenic vertical carbon flux in the Southern Ocean

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marchant, H.J.; Davidson, A.

1992-03-01

Among the most productive region of the Southern Ocean is the marginal ice edge zone that trails the retreating ice edge in spring and early summer. The timing of this near-surface phytoplankton bloom coincides with seasonal stratospheric ozone depletion when UV irradiance is reportedly as high as in mid-summer. Recent investigations indicate that antarctic marine phytoplankton are presently UV stressed. The extent to which increasing UV radiation diminishes the ability of phytoplankton to fix C02 and/or leads to changes in their species composition is equivocal. The colonial stage in the life cycle of the alga Phaeocystis pouchetii is one ofmore » the major components of the bloom. The authors have found that this alga produces extracellular products which are strongly UV-B absorbing. When exposed to increasing levels of UV-B radiation, survival of antarctic colonial Phaeocystis was significantly greater than colonies of this species from temperate waters and of the single-celled stage of its life cycle which produces no UV-B-absorbing compounds. Phaeocystis is apparently a minor dietary component of Antarctic krill, Euphausia superba, and its nutritional value to crustacea is reportedly low. Phytoplankton, principally diatoms, together with fecal pellets and molted exoskeletons of grazers contribute most of the particulate carbon flux from the euphotic zone to deep water.« less

Acoustic Observation of Living Organisms Reveals the Upper Limit of the Oxygen Minimum Zone

PubMed Central

Bertrand, Arnaud; Ballón, Michael; Chaigneau, Alexis

2010-01-01

Background Oxygen minimum zones (OMZs) are expanding in the World Ocean as a result of climate change and direct anthropogenic influence. OMZ expansion greatly affects biogeochemical processes and marine life, especially by constraining the vertical habitat of most marine organisms. Currently, monitoring the variability of the upper limit of the OMZs relies on time intensive sampling protocols, causing poor spatial resolution. Methodology/Principal Findings Using routine underwater acoustic observations of the vertical distribution of marine organisms, we propose a new method that allows determination of the upper limit of the OMZ with a high precision. Applied in the eastern South-Pacific, this original sampling technique provides high-resolution information on the depth of the upper OMZ allowing documentation of mesoscale and submesoscale features (e.g., eddies and filaments) that structure the upper ocean and the marine ecosystems. We also use this information to estimate the habitable volume for the world's most exploited fish, the Peruvian anchovy (Engraulis ringens). Conclusions/Significance This opportunistic method could be implemented on any vessel geared with multi-frequency echosounders to perform comprehensive high-resolution monitoring of the upper limit of the OMZ. Our approach is a novel way of studying the impact of physical processes on marine life and extracting valid information about the pelagic habitat and its spatial structure, a crucial aspect of Ecosystem-based Fisheries Management in the current context of climate change. PMID:20442791

In-situ atrazine biodegradation dynamics in wheat (Triticum) crops under variable hydrologic regime.

PubMed

la Cecilia, Daniele; Maggi, Federico

2017-08-01

A comprehensive biodegradation reaction network of atrazine (ATZ) and its 18 byproducts was coupled to the nitrogen cycle and integrated in a computational solver to assess the in-situ biodegradation effectiveness and leaching along a 5m deep soil cultivated with wheat in West Wyalong, New South Wales, Australia. Biodegradation removed 97.7% of 2kg/ha ATZ yearly applications in the root zone, but removal substantially decreased at increasing depths; dechlorination removed 79% of ATZ in aerobic conditions and 18% in anaerobic conditions, whereas deethylation and oxidation removed only 0.11% and 0.15% of ATZ, respectively. The residual Cl mass fraction in ATZ and 4 byproducts was 2.4% of the applied mass. ATZ half-life ranged from 150 to 247days in the soil surface. ATZ reached 5m soil depth within 200years and its concentration increased from 1×10 -6 to 4×10 -6 mg/kg dry-soil over time. The correlation between ATZ specific biomass degradation affinity Φ 0 and half-life t 1/2 , although relatively uncertain for both hydrolyzing and oxidizing bacteria, suggested that microorganisms with high Φ 0 led to low ATZ t 1/2 . Greater ATZ applications were balanced by small nonlinear increments of ATZ biodegraded fraction within the root zone and therefore less ATZ leached into the shallow aquifer. Copyright © 2017 Elsevier B.V. All rights reserved.

Evaluation of the Implementation of Family Life and HIV Education Programme in Nigeria.

PubMed

Udegbe, Bola I; Fayehun, Funke; Isiugo-Abanihe, Uche C; Nwagwu, Williams; Isiugo-Abanihe, Ifeoma; Nwokocha, Ezebunwa

2015-06-01

Family Life and HIV Education (FLHE) programme was introduced nationwide in Nigeria in 2003. Since then little is known about the patterns of its implementation across the states in the six geo-political zones in Nigeria. This study represents an attempt to fill this lacuna in the FLHE literature in Nigeria. Quantitative data was collected from the Federal Ministry of Education and the State Ministries of Education on all salient aspects of FLHE implementation. The findings from data collected in 35 states and the Abuja Federal Capital Territory show large variations in the year of adoption of the programme, level of implementation of the programme, the proportion of implementing schools that are reporting to the coordinating government ministries/agencies, the level to which schools have been supplied with relevant curriculum, and promptness of distribution of materials across the zones. All these indices did not show significant level of interdependence. In general, there were higher levels of FLHE activities in the South than the North. Several problems affect implementation of FLHE in Nigeria, most of which will require increased financial and technical support from government and other organizations. The FLHE programme has had positive effects in the states and among schools where the implementation has been effective, underscoring the need for a more effective implementation of the programmes throughout the country.

Food web topology and parasites in the pelagic zone of a subarctic lake

USGS Publications Warehouse

Amundsen, Per-Arne; Lafferty, K.D.; Knudsen, R.; Primicerio, R.; Klemetsen, A.; Kuris, A.M.

2009-01-01

Parasites permeate trophic webs with their often complex life cycles, but few studies have included parasitism in food web analyses. Here we provide a highly resolved food web from the pelagic zone of a subarctic lake and explore how the incorporation of parasites alters the topology of the web. 2. Parasites used hosts at all trophic levels and increased both food-chain lengths and the total number of trophic levels. Their inclusion in the network analyses more than doubled the number of links and resulted in an increase in important food-web characteristics such as linkage density and connectance. 3. More than half of the parasite taxa were trophically transmitted, exploiting hosts at multiple trophic levels and thus increasing the degree of omnivory in the trophic web. 4. For trophically transmitted parasites, the number of parasite-host links exhibited a positive correlation with the linkage density of the host species, whereas no such relationship was seen for nontrophically transmitted parasites. Our findings suggest that the linkage density of free-living species affects their exposure to trophically transmitted parasites, which may be more likely to adopt highly connected species as hosts during the evolution of complex life cycles. 5. The study supports a prominent role for parasites in ecological networks and demonstrates that their incorporation may substantially alter considerations of food-web structure and functioning. ?? 2009 British Ecological Society.

In-situ atrazine biodegradation dynamics in wheat (Triticum) crops under variable hydrologic regime

NASA Astrophysics Data System (ADS)

la Cecilia, Daniele; Maggi, Federico

2017-08-01

A comprehensive biodegradation reaction network of atrazine (ATZ) and its 18 byproducts was coupled to the nitrogen cycle and integrated in a computational solver to assess the in-situ biodegradation effectiveness and leaching along a 5 m deep soil cultivated with wheat in West Wyalong, New South Wales, Australia. Biodegradation removed 97.7% of 2 kg/ha ATZ yearly applications in the root zone, but removal substantially decreased at increasing depths; dechlorination removed 79% of ATZ in aerobic conditions and 18% in anaerobic conditions, whereas deethylation and oxidation removed only 0.11% and 0.15% of ATZ, respectively. The residual Cl mass fraction in ATZ and 4 byproducts was 2.4% of the applied mass. ATZ half-life ranged from 150 to 247 days in the soil surface. ATZ reached 5 m soil depth within 200 years and its concentration increased from 1 ×10-6 to 4 ×10-6 mg/kgdry-soil over time. The correlation between ATZ specific biomass degradation affinity Φ0 and half-life t1/2, although relatively uncertain for both hydrolyzing and oxidizing bacteria, suggested that microorganisms with high Φ0 led to low ATZ t1/2. Greater ATZ applications were balanced by small nonlinear increments of ATZ biodegraded fraction within the root zone and therefore less ATZ leached into the shallow aquifer.

Effects of the insecticide permethrin on three life stages of the grass shrimp, Palaemonetes pugio.

PubMed

DeLorenzo, M E; Serrano, L; Chung, K W; Hoguet, J; Key, P B

2006-06-01

Toxicity of the pyrethroid insecticide permethrin was assessed using three life stages of the estuarine grass shrimp, Palaemonetes pugio. Adult and larval shrimp were tested with and without sediment. An aqueous embryo test was also conducted. Cellular stress biomarkers, glutathione, and lipid peroxidation, were assessed. Larval shrimp were the most sensitive life stage with a 96-h lethal concentration (LC(50)) value of 0.05 microg/L, compared to 0.25 microg/L for adults, and 6.4 microg/L for embryos. The presence of sediment significantly decreased toxicity of permethrin to both adult and larval shrimp. Permethrin exposure increased time to hatch in embryos and decreased swimming behavior of larvae. Lipid peroxidation levels were significantly decreased in the adult shrimp, but increased in larval shrimp exposed to permethrin. Low levels of permethrin may negatively affect grass shrimp health and survival. Permethrin use in the coastal zone should be carefully managed to avoid adverse impacts on nontarget estuarine organisms.

Ultraviolet radiation from F and K stars and implications for planetary habitability.

PubMed

Kasting, J F; Whittet, D C; Sheldon, W R

1997-08-01

Now that extrasolar planets have been found, it is timely to ask whether some of them might be suitable for life. Climatic constraints on planetary habitability indicate that a reasonably wide habitable zone exists around main sequence stars with spectral types in the early-F to mid-K range. However, it has not been demonstrated that planets orbiting such stars would be habitable when biologically-damaging energetic radiation is also considered. The large amounts of UV radiation emitted by early-type stars have been suggested to pose a problem for evolving life in their vicinity. But one might also argue that the real problem lies with late-type stars, which emit proportionally less radiation at the short wavelengths (lambda < 200 nm) required to split O2 and initiate ozone formation. We show here that neither of these concerns is necessarily fatal to the evolution of advanced life: Earth-like planets orbiting F and K stars may well receive less harmful UV radiation at their surfaces than does the Earth itself.

Ultraviolet radiation from F and K stars and implications for planetary habitability

NASA Technical Reports Server (NTRS)

Kasting, J. F.; Whittet, D. C.; Sheldon, W. R.

1997-01-01

Now that extrasolar planets have been found, it is timely to ask whether some of them might be suitable for life. Climatic constraints on planetary habitability indicate that a reasonably wide habitable zone exists around main sequence stars with spectral types in the early-F to mid-K range. However, it has not been demonstrated that planets orbiting such stars would be habitable when biologically-damaging energetic radiation is also considered. The large amounts of UV radiation emitted by early-type stars have been suggested to pose a problem for evolving life in their vicinity. But one might also argue that the real problem lies with late-type stars, which emit proportionally less radiation at the short wavelengths (lambda < 200 nm) required to split O2 and initiate ozone formation. We show here that neither of these concerns is necessarily fatal to the evolution of advanced life: Earth-like planets orbiting F and K stars may well receive less harmful UV radiation at their surfaces than does the Earth itself.

Exchange of Biomaterial Between Planetary Systems

NASA Astrophysics Data System (ADS)

Napier, W. M.

2011-10-01

It is now known that dynamical highways exist along which viable microorganisms may travel between the planets of the solar system. The extension of this concept to interstellar distances is explored here. Giant molecular clouds play a significant role in the process. They stimulate exoplanetary systems by disturbing their comet clouds and enhancing planetary impact rates. Biomaterial thrown out by impacts is injected directly into their stellar nurseries, with transfer times typically 0.1-0.5 million years. With reasonably conservative assumptions it is expected that, if life started at one locality in the Galaxy 5-10 Gyr ago, it would by now occupy ecological niches throughout the habitable zone. The chief uncertainty is the proportion of planetary systems capable of receiving life, nurturing it and re-ejecting it through impacts: a critical proportion of ˜10-3 to ˜10-4 such exoplanetary systems is necessary for the diffusion of life to go critical in the solar neighbourhood. This requirement is relaxed within ˜3-5 kpc of the Galactic centre.

Risks for Life on Habitable Planets from Superflares of Their Host Stars

NASA Astrophysics Data System (ADS)

Lingam, Manasvi; Loeb, Abraham

2017-10-01

We explore some of the ramifications arising from superflares on the evolutionary history of Earth, other planets in the solar system, and exoplanets. We propose that the most powerful superflares can serve as plausible drivers of extinction events, and that their periodicity corresponds to certain patterns in the terrestrial fossil diversity record. On the other hand, weaker superflares may play a positive role in enabling the origin of life through the formation of key organic compounds. Superflares could also prove to be quite detrimental to the evolution of complex life on present-day Mars and exoplanets in the habitable zone of M- and K-dwarfs. We conclude that the risk posed by superflares has not been sufficiently appreciated, and that humanity might potentially witness a superflare event in the next ˜ {10}3 years, leading to devastating economic and technological losses. In light of the many uncertainties and assumptions associated with our analysis, we recommend that these results should be viewed with due caution.

Quantification of the Service Life Extension and Environmental Benefit of Chloride Exposed Self-Healing Concrete

PubMed Central

Van Belleghem, Bjorn; Van den Heede, Philip; Van Tittelboom, Kim; De Belie, Nele

2016-01-01

Formation of cracks impairs the durability of concrete elements. Corrosion inducing substances, such as chlorides, can enter the matrix through these cracks and cause steel reinforcement corrosion and concrete degradation. Self-repair of concrete cracks is an innovative technique which has been studied extensively during the past decade and which may help to increase the sustainability of concrete. However, the experiments conducted until now did not allow for an assessment of the service life extension possible with self-healing concrete in comparison with traditional (cracked) concrete. In this research, a service life prediction of self-healing concrete was done based on input from chloride diffusion tests. Self-healing of cracks with encapsulated polyurethane precursor formed a partial barrier against immediate ingress of chlorides through the cracks. Application of self-healing concrete was able to reduce the chloride concentration in a cracked zone by 75% or more. As a result, service life of steel reinforced self-healing concrete slabs in marine environments could amount to 60–94 years as opposed to only seven years for ordinary (cracked) concrete. Subsequent life cycle assessment calculations indicated important environmental benefits (56%–75%) for the ten CML-IA (Center of Environmental Science of Leiden University–Impact Assessment) baseline impact indicators which are mainly induced by the achievable service life extension. PMID:28772363

The Possible Emergence of Life and Differentiation of a Shallow Biosphere on Irradiated Icy Worlds: The Example of Europa.

PubMed

Russell, Michael J; Murray, Alison E; Hand, Kevin P

2017-12-01

Irradiated ice-covered ocean worlds with rocky mafic mantles may provide the conditions needed to drive the emergence and maintenance of life. Alkaline hydrothermal springs-relieving the geophysical, thermal, and chemical disequilibria between oceans and tidally stressed crusts-could generate inorganic barriers to the otherwise uncontrolled and kinetically disfavored oxidation of hydrothermal hydrogen and methane. Ionic gradients imposed across these inorganic barriers, comprising iron oxyhydroxides and sulfides, could drive the hydrogenation of carbon dioxide and the oxidation of methane through thermodynamically favorable metabolic pathways leading to early life-forms. In such chemostatic environments, fuels may eventually outweigh oxidants. Ice-covered oceans are primarily heated from below, creating convection that could transport putative microbial cells and cellular cooperatives upward to congregate beneath an ice shell, potentially giving rise to a highly focused shallow biosphere. It is here where electron acceptors, ultimately derived from the irradiated surface, could be delivered to such life-forms through exchange with the icy surface. Such zones would act as "electron disposal units" for the biosphere, and occupants might be transferred toward the surface by buoyant diapirs and even entrained into plumes. Key Words: Biofilms-Europa-Extraterrestrial life-Hydrothermal systems. Astrobiology 17, 1265-1273.

Editorial: Special issue “Planetary evolution and life”

NASA Astrophysics Data System (ADS)

Spohn, Tilman

2014-08-01

Given the enormous number of stars in the universe and the number of confirmed and postulated planets in our galaxy, it is generally agreed that our home planet Earth is not likely to be unique (e.g., Sagan, 1980; Bignami et al., 2005; Hawking and Mlodinow, 2010). But is it? Although the number of known extrasolar planets grows almost by the day, observational bias caused by the technological challenges of finding Earth-size, rocky extrasolar planets and determining their masses and sizes have thus far prohibited the detection of a second Earth. But even if a second Earth were to be found-located in what is termed the habitable zone (e.g., Kasting et al., 1993)-can we expect that life would have originated there and have evolved beyond the most primitive forms? Is the universe "bio-friendly" as Paul Davies said (cited after Sullivan and Baross, 2007) using the Anthropic Principle (Barrow and Tipler, 1986) or is the origin of life so complex and our home planet so peculiar (Ward and Brownlee, 2000) that we are the unlikely product of a chain of unlikely events (Gould, 1989)? And if life existed on a second Earth or on many other planets, would we be able to detect it? Would life have shaped these planets such as life has shaped the Earth?

Distribution of greenhouse gases in hyper-arid and arid areas of northern Chile and the contribution of the high altitude wetland microbiome (Salar de Huasco, Chile).

PubMed

Molina, Verónica; Eissler, Yoanna; Cornejo, Marcela; Galand, Pierre E; Dorador, Cristina; Hengst, Martha; Fernandez, Camila; Francois, Jean Pierre

2018-04-06

Northern Chile harbors different bioclimatic zones including hyper-arid and arid ecosystems and hotspots of microbial life, such as high altitude wetlands, which may contribute differentially to greenhouse gases (GHG) such as carbon dioxide (CO 2 ), methane (CH 4 ) and nitrous oxide (N 2 O). In this study, we explored ground level GHG distribution and the potential role of a wetland situated at 3800 m.a.s.l, and characterized by high solar radiation < 1600 W m -2 , extreme temperature ranges (-12 to 24 °C) and wind stress (< 17 m s -1 ). The water source of the wetland is mainly groundwater springs, which generates streams and ponds surrounded by peatlands. These sites support a rich microbial aquatic life including diverse bacteria and archaea communities, which transiently form more complex structures, such as microbial mats. In this study, GHG were measured in the water and above ground level air at the wetland site and along an elevation gradient in different bioclimatic areas from arid to hyper-arid zones. The microbiome from the water and sediments was described by high-throughput sequencing 16S rRNA and rDNA genes. The results indicate that GHG at ground level were variable along the elevation gradient potentially associated with different bioclimatic zones, reaching high values at the high Andean steppe and variable but lower values in the Atacama Desert and at the wetland. The water areas of the wetland presented high concentrations of CH 4 and CO 2 , particularly at the spring areas and in air bubbles below microbial mats. The microbial community was rich (> 40 phyla), including archaea and bacteria potentially active in the different matrices studied (water, sediments and mats). Functional microbial groups associated with GHG recycling were detected at low frequency, i.e., < 2.5% of total sequences. Our results indicate that hyper-arid and arid areas of northern Chile are sites of GHG exchange associated with various bioclimatic zones and particularly in aquatic areas of the wetland where this ecosystem could represent a net sink of N 2 O and a source for CH 4 and CO 2 .

Role of Sediments and Nutrients in the Condition of a Coral Reef Under Tourist Pressure: Akumal México.

NASA Astrophysics Data System (ADS)

Naranjo-Garcia, M. J.; Vadés Lozano, D. S.; Real-De-Leon, E.; Lopez-Aguiar, K.; Garza-Perez, J. R.

2014-12-01

Akumal, Mexico, was the first tourist resort in the Mexican Caribbean mainland, its highly developed coastal zone lies directly above the phreatic, and it is directly connected to the sub-littoral waters. Akumal is also known as a well-developed fringing coral reef, now in a critical condition. The main objective of this study was to explore the relationship between two of the main indicators of human pressure (nutrients and sedimentation, linked to coastal development and water run-offs) and the condition of the reef benthos, during a year. The sampling design used four transects perpendicular to shore, associated to different tourist and water run-off exposure, for a total of 12 stations distributed in three different reef zones (transition zone, shallow and deep spurs and grooves). Monthly samples were collected: water samples close to the reef lagoon drain channels and at bottom depth at each station, and sediment traps were recovered and replaced also at each station. Reef Benthos videotransects were recorded bi-monthly at each station to assess its condition. Macroalgae and filamentous algae dominate benthic cover (up to 50%), hard-coral cover ranges from 5-9%. Five coral-diseases were recorded, affecting 10.16% of the coral colonies: Caribbean Ciliate Infection, White Band, Purple Spots, White Spots and Yellow Band. The sedimentation rate -sr- ranged from 0.13 to 83.7 mg/cm2/day during the year; 86% of the samples had a sr ≤ 10 mg/cm2/day (reefs not stressed); 13% of the samples had a sr ranging from 10 to 50 mg/cm2/day (stressed reefs); and 1% of the samples were over the critical threshold (>50 mg/cm2/day). Dissolved Inorganic Nitrogen concentrations during the year were above those recorded previously in Caribbean reefs. The most abundant fraction was ammonium, surpassing both Mexican norms: For protection of aquatic life in coastal zones (0.01 mg/L), and the critical threshold for aquatic life (0.4 mg/L). These concentration limits are considered as drivers of eutrophication, one of the main established causes of reef degradation globally. High concentrations of ammonium and other nutrients have been linked to increases in algae cover and coral diseases incidence, and to decreases in rates of coral calcification, fertility, production and viability of coral larvae, and the associated diversity loss.

Impacts of Quaternary History on Critical Zone Structure and Processes: Examples and a Conceptual Model from the Intensively Managed Landscapes Critical Zone Observatory

NASA Astrophysics Data System (ADS)

Anders, Alison M.; Bettis, E. Arthur; Grimley, David A.; Stumpf, Andrew J.; Kumar, Praveen

2018-03-01

The concept of a critical zone (CZ) supporting terrestrial life has fostered groundbreaking interdisciplinary science addressing complex interactions among water, soil, rock, air and life near Earth’s surface. Pioneering work has focused on the CZ in areas with residual soils and steady-state or erosional topography. CZ evolution in these areas is conceptualized as progressive weathering of local bedrock (e.g. in the flow-through reactor model). However, this model is not applicable to areas in which weathering profiles form in transported materials including the formerly glaciated portion of the Central Lowland of North America. We present a new conceptual model of CZ evolution in landscapes impacted by continental glaciation based on investigations at three study sites in the Intensively Managed Landscapes Critical Zone Observatory (IML-CZO) The IML-CZO is devoted to the study of CZ processes in a region characterized by thick surficial deposits resulting from multiple continental glaciations, with bedrock at depths of up to 150 m. Here the physical (glacial ice, loess, developing soil profiles) and biological (microbes, tundra, forest, prairie) components of the CZ vary significantly in time. Moreover, the spatial relationships between mineral components of the CZ record a history of glacial-interglacial cycles and landscape evolution. We present cross-sections from IML-CZO sites to provide specific examples of how environmental change is recorded by the structure of the mineral components of the CZ. We build on these examples to create an idealized model of CZ evolution through a glacial cycle that represents the IML-CZO sites and other areas of low relief that have experienced continental glaciation. In addition, we identify two main characteristics of CZ structure which should be included in a conceptual model of CZ development in the IML-CZO and similar settings: (1) mineral components have diverse origins and transport trajectories including alteration in past CZs, and, (2) variability in climate, ecosystems, and hydrology during glacial-interglacial cycles profoundly influence the CZ composition, creating a legacy retained in its structure. This legacy is important because the current physical CZ structure influences the occurrence and rates of CZ processes, as well as future CZ responses to land use and climate change.

Fish functional traits correlated with environmental variables in a temperate biodiversity hotspot.

PubMed

Keck, Benjamin P; Marion, Zachary H; Martin, Derek J; Kaufman, Jason C; Harden, Carol P; Schwartz, John S; Strange, Richard J

2014-01-01

The global biodiversity crisis has invigorated the search for generalized patterns in most disciplines within the natural sciences. Studies based on organismal functional traits attempt to broaden implications of results by identifying the response of functional traits, instead of taxonomic units, to environmental variables. Determining the functional trait responses enables more direct comparisons with, or predictions for, communities of different taxonomic composition. The North American freshwater fish fauna is both diverse and increasingly imperiled through human mediated disturbances, including climate change. The Tennessee River, USA, contains one of the most diverse assemblages of freshwater fish in North America and has more imperiled species than other rivers, but there has been no trait-based study of community structure in the system. We identified 211 localities in the upper Tennessee River that were sampled by the Tennessee Valley Authority between 2009 and 2011 and compiled fish functional traits for the observed species and environmental variables for each locality. Using fourth corner analysis, we identified significant correlations between many fish functional traits and environmental variables. Functional traits associated with an opportunistic life history strategy were correlated with localities subject to greater land use disturbance and less flow regulation, while functional traits associated with a periodic life history strategy were correlated with localities subject to regular disturbance and regulated flow. These are patterns observed at the continental scale, highlighting the generalizability of trait-based methods. Contrary to studies that found no community structure differences when considering riparian buffer zones, we found that fish functional traits were correlated with different environmental variables between analyses with buffer zones vs. entire catchment area land cover proportions. Using existing databases and fourth corner analysis, our results support the broad application potential for trait-based methods and indicate trait-based methods can detect environmental filtering by riparian zone land cover.

Fish Functional Traits Correlated with Environmental Variables in a Temperate Biodiversity Hotspot

PubMed Central

Keck, Benjamin P.; Marion, Zachary H.; Martin, Derek J.; Kaufman, Jason C.; Harden, Carol P.; Schwartz, John S.; Strange, Richard J.

2014-01-01

The global biodiversity crisis has invigorated the search for generalized patterns in most disciplines within the natural sciences. Studies based on organismal functional traits attempt to broaden implications of results by identifying the response of functional traits, instead of taxonomic units, to environmental variables. Determining the functional trait responses enables more direct comparisons with, or predictions for, communities of different taxonomic composition. The North American freshwater fish fauna is both diverse and increasingly imperiled through human mediated disturbances, including climate change. The Tennessee River, USA, contains one of the most diverse assemblages of freshwater fish in North America and has more imperiled species than other rivers, but there has been no trait-based study of community structure in the system. We identified 211 localities in the upper Tennessee River that were sampled by the Tennessee Valley Authority between 2009 and 2011 and compiled fish functional traits for the observed species and environmental variables for each locality. Using fourth corner analysis, we identified significant correlations between many fish functional traits and environmental variables. Functional traits associated with an opportunistic life history strategy were correlated with localities subject to greater land use disturbance and less flow regulation, while functional traits associated with a periodic life history strategy were correlated with localities subject to regular disturbance and regulated flow. These are patterns observed at the continental scale, highlighting the generalizability of trait-based methods. Contrary to studies that found no community structure differences when considering riparian buffer zones, we found that fish functional traits were correlated with different environmental variables between analyses with buffer zones vs. entire catchment area land cover proportions. Using existing databases and fourth corner analysis, our results support the broad application potential for trait-based methods and indicate trait-based methods can detect environmental filtering by riparian zone land cover. PMID:24676053

[Differences in the health and disease conditions in the rural and urban-suburban populations in Nuevo León state].

PubMed

Kroeger, A; Malo, F; Pérez Samaniego, C; Berg, H

1991-01-01

This work shows the results of two surveys taken in the state of Nuevo León, Mexico during 1985. The first survey, which covered morbidity and health service use, was taken from 759 households in urban/suburban Monterrey (a city of two million inhabitants and capital of the state of Nuevo León) and from 751 households from a stratified sample from the rest of the state. The second survey, which had to do with the different aspects of quality health services available, was given to 752 patients in 93 distinct health units in Monterrey and all over the state. The objectives of this publication are: 1) to describe the morbidity of the populations in question, as well as to describe the different aspects of the supply and demand of health services; 2) to compare the conditions of life reflected in the state of health between the rural and urban/suburban zones of Nuevo León. The results obtained show that those in the urban/suburban zones of Monterrey possess certain advantages over those in the rural areas in the state of Nuevo León such as: a higher level of schooling, lower emigration to the U.S.A., a lower fertility index, lower morbidity from severe illnesses and a lower death rate in children, wider coverage from health insurance, better communication between doctor and patient, more frequent use of health services, and greater participation in prevention programs. Rural area life has the following advantages: a lower number of cesarean sections, and a prolonged period of maternal suckling. In this work, we present the opinion that the primary health care currently centered in the urban zones, where the population is much greater, should not impair the required attention in the rural areas (areas that are more extensive and often unattended).

PTSD and trauma in Austria's elderly: influence of wartime experiences, postwar zone of occupation, and life time traumatization on today's mental health status—an interdisciplinary approach

PubMed Central

Glück, Tobias M.; Tran, Ulrich S.; Lueger-Schuster, Brigitte

2012-01-01

Background While in recent years epidemiological studies on World War (WW) II-related traumatization and prevalence of posttraumatic stress disorder (PTSD) in elderly persons have been conducted for various European countries, for Austria, these numbers are unknown. Objective The focus of this epidemiologic study was to picture the current mental health status and prevalence of PTSD and lifetime traumatic events in Austria's elderly with respect to WWII and subsequent occupation. Method In an interdisciplinary approach of psychologists and historians, 316 elderly Austrians (born before 1946) were interviewed for symptoms of PTSD and lifetime traumatization (Traumatic Life Events Questionnaire, PTSD Checklist-Civilian Version), current mental health (Brief Symptom Inventory), wartime-related trauma, and traumatic experiences with occupational forces. These factors were also compared regarding the zone of occupation (Allied vs. Soviet). Data were collected between March and September 2010. Results 97.5% of the sample reported at least one lifetime trauma. War-related traumata were reported by 92.7% and non-war-related traumata by 82.3%; 40.2% experienced traumatic events with occupational forces. PTSD was present in 1.9% of the sample and up to 13.9% taking subthreshold PTSD into account. Both, the presence of symptoms indicative of PTSD and subthreshold PTSD implied weaker current mental health (regarding General Distress: odds ratios up to 25.51; 95% CI = 9.82 to 66.27). Independent of PTSD diagnosis persons from the Soviet occupied zone showed higher levels of Interpersonal Sensitivity, Global Distress, and Phobic Anxiety. Prevalence of PTSD was independent of gender. Conclusions Our results corroborate findings from other European countries that PTSD is a common disorder in the elderly due to WWII experience and that PTSD and trauma affect mental health even across long periods of time. Postwar distressing conditions also pose a further risk factor for symptomatology and distress in later years. PMID:22893846

Natural History of the Central Structural Abnormalities in Choroideremia: A Prospective Cross-Sectional Study.

PubMed

Aleman, Tomas S; Han, Grace; Serrano, Leona W; Fuerst, Nicole M; Charlson, Emily S; Pearson, Denise J; Chung, Daniel C; Traband, Anastasia; Pan, Wei; Ying, Gui-Shuang; Bennett, Jean; Maguire, Albert M; Morgan, Jessica I W

2017-03-01

To describe in detail the central retinal structure of a large group of patients with choroideremia (CHM). A prospective, cross-sectional, descriptive study. Patients (n = 97, age 6-71 years) with CHM and subjects with normal vision (n = 44; ages 10-50 years) were included. Subjects were examined with spectral-domain optical coherence tomography (SD OCT) and near-infrared reflectance imaging. Visual acuity (VA) was measured during their encounter or obtained from recent ophthalmic examinations. Visual thresholds were measured in a subset of patients (n = 24) with automated static perimetry within the central regions (±15°) examined with SD OCT. Visual acuity and visual thresholds; total nuclear layer, inner nuclear layer (INL), and outer nuclear layer (ONL) thicknesses; and horizontal extent of the ONL and the photoreceptor outer segment (POS) interdigitation zone (IZ). Earliest abnormalities in regions with normally appearing retinal pigment epithelium (RPE) were the loss of the POS and ellipsoid zone associated with rod dysfunction. Transition zones (TZs) from relatively preserved retina to severe ONL thinning and inner retinal thickening moved centripetally with age. Most patients (88%) retained VAs better than 20/40 until their fifth decade of life. The VA decline coincided with migration of the TZ near the foveal center. There were outer retinal tubulations in degenerated, nonatrophic retina in the majority (69%) of patients. In general, RPE abnormalities paralleled photoreceptor degeneration, although there were regions with detectable but abnormally thin ONL co-localizing with severe RPE depigmentation and choroidal thinning. Abnormalities of the POS and rod dysfunction are the earliest central abnormalities observed in CHM. Foveal function is relatively preserved until the fifth decade of life. Migration of the TZs to the foveal center with foveal thinning and structural disorganization heralded central VA loss. The relationships established may help outline the eligibility criteria and outcome measures for clinical trials for CHM. Copyright © 2016 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

A reappraisal of the habitability of planets around M dwarf stars.

PubMed

Tarter, Jill C; Backus, Peter R; Mancinelli, Rocco L; Aurnou, Jonathan M; Backman, Dana E; Basri, Gibor S; Boss, Alan P; Clarke, Andrew; Deming, Drake; Doyle, Laurance R; Feigelson, Eric D; Freund, Friedmann; Grinspoon, David H; Haberle, Robert M; Hauck, Steven A; Heath, Martin J; Henry, Todd J; Hollingsworth, Jeffery L; Joshi, Manoj M; Kilston, Steven; Liu, Michael C; Meikle, Eric; Reid, I Neill; Rothschild, Lynn J; Scalo, John; Segura, Antigona; Tang, Carol M; Tiedje, James M; Turnbull, Margaret C; Walkowicz, Lucianne M; Weber, Arthur L; Young, Richard E

2007-02-01

Stable, hydrogen-burning, M dwarf stars make up about 75% of all stars in the Galaxy. They are extremely long-lived, and because they are much smaller in mass than the Sun (between 0.5 and 0.08 M(Sun)), their temperature and stellar luminosity are low and peaked in the red. We have re-examined what is known at present about the potential for a terrestrial planet forming within, or migrating into, the classic liquid-surface-water habitable zone close to an M dwarf star. Observations of protoplanetary disks suggest that planet-building materials are common around M dwarfs, but N-body simulations differ in their estimations of the likelihood of potentially habitable, wet planets that reside within their habitable zones, which are only about one-fifth to 1/50th of the width of that for a G star. Particularly in light of the claimed detection of the planets with masses as small as 5.5 and 7.5 M(Earth) orbiting M stars, there seems no reason to exclude the possibility of terrestrial planets. Tidally locked synchronous rotation within the narrow habitable zone does not necessarily lead to atmospheric collapse, and active stellar flaring may not be as much of an evolutionarily disadvantageous factor as has previously been supposed. We conclude that M dwarf stars may indeed be viable hosts for planets on which the origin and evolution of life can occur. A number of planetary processes such as cessation of geothermal activity or thermal and nonthermal atmospheric loss processes may limit the duration of planetary habitability to periods far shorter than the extreme lifetime of the M dwarf star. Nevertheless, it makes sense to include M dwarf stars in programs that seek to find habitable worlds and evidence of life. This paper presents the summary conclusions of an interdisciplinary workshop (http://mstars.seti.org) sponsored by the NASA Astrobiology Institute and convened at the SETI Institute.

Life's Starting Materials Found in Dusty Disk

NASA Technical Reports Server (NTRS)

2005-01-01

[figure removed for brevity, see original site] Full Image of Graph

This graph, or spectrum, from NASA's Spitzer Space Telescope tells astronomers that some of the most basic ingredients of DNA and protein are concentrated in a dusty planet-forming disk circling a young sun-like star called IRS 46. These data also indicate that the ingredients -- molecular gases called acetylene and hydrogen cyanide -- are located in the star's terrestrial planet zone, the region where scientists believe Earth-like planets would be most likely to form.

The data were acquired by Spitzer's infrared spectrograph, which split light from the star's disk into distinct features characteristic of a particular chemical. The features, seen here as bumps and squiggles, are like bar codes used in supermarkets to identify different products. In this case, the products are the two DNA and protein precursors, acetylene and hydrogen cyanide, as well as carbon dioxide gas. All three gases are termed 'organic' because they contain the element carbon.

The shapes of the features in this spectrum helped pinpoint the location of the gases in the star's disk. A feature's shape reflects the temperature of the gas. By comparison with model spectra, astronomers were able to deduce that the gases are present in regions where the temperature ranges from approximately the boiling point of water on Earth (212 degrees Fahrenheit), to nearly a thousand degrees Fahrenheit. Such hot temperatures place the gases in the star's terrestrial planet zone, which is sometimes referred to as the 'Goldilocks' zone because it is just right for Earths.

Acetylene and hydrogen cyanide are some of life's most basic starting materials. If you mix them together in a test tube with water, and give them some kind of surface on which to be concentrated and react, you'll get a slew of organic compounds, including many of the 20 essential amino acids and one of the four chemical units, called bases, that make up DNA.

Methane production and consumption monitored by stable H and C isotope ratios at a crude oil spill site, Bemidji, Minnesota

USGS Publications Warehouse

Revesz, Kinga; Coplen, Tyler B.; Baedecker, Mary J.; Glynn, Pierre D.

1995-01-01

Stable isotopic ratios of C and H in dissolved CH4 and C in dissolved inorganic C in the ground water of a crude-oil spill near Bemidji, Minnesota, support the concept of CH4production by acetate fermentation with a contemporaneous increase in HCO3−concentration. Methane concentrations in the saturated zone decrease from 20.6 mg L−1 to less than 0.001 mg L−1 along the investigated flow path. Dissolved N2 and Ar concentrations in the ground water below the oil plume are 25 times lower than background; this suggests that gas exsolution is removing dissolved CH4 (along with other dissolved gases) from the ground water. Oxidation of dissolved CH4 along the flow path seems to be minimal because no measurable change in isotopic composition of CH4 occurs with distance from the oil body. However, CH4 is partly oxidized to CO2 as it diffuses upward from the ground water through a 5- to 7-m thick unsaturated zone; theδ13C of the remaining CH4 increases, theδ13C of the CO2 decreases, and the partial pressure of CO2 increases.Calculations of C fluxes in the saturated and unsaturated zones originating from the degradation of the oil plume lead to a minimum estimated life expectancy of 110 years. This is a minimum estimate because the degradation of the oil body should slow down with time as its more volatile and reactive components are leached out and preferentially oxidized. The calculated life expectancy is an order of magnitude estimate because of the uncertainty in the average linear ground-water velocities and because of the factor of 2 uncertainty in the calculation of the effective CO2 diffusion coefficient.

Prebiotic synthesis of adenine and amino acids under Europa-like conditions

NASA Technical Reports Server (NTRS)

Levy, M.; Miller, S. L.; Brinton, K.; Bada, J. L.

2000-01-01

In order to simulate prebiotic synthetic processes on Europa and other ice-covered planets and satellites, we have investigated the prebiotic synthesis of organic compounds from dilute solutions of NH4CN frozen for 25 years at -20 and -78 degrees C. In addition, the aqueous products of spark discharge reactions from a reducing atmosphere were frozen for 5 years at -20 degrees C. We find that both adenine and guanine, as well as a simple set of amino acids dominated by glycine, are produced in substantial yields under these conditions. These results indicate that some of the key components necessary for the origin of life may have been available on Europa throughout its history and suggest that the circumstellar zone where life might arise may be wider than previously thought.

Maximum number of habitable planets at the time of Earth's origin: new hints for panspermia?

PubMed

von Bloh, Werner; Franck, Siegfried; Bounama, Christine; Schellnhuber, Hans-Joachim

2003-04-01

New discoveries have fuelled the ongoing discussion of panspermia, i.e. the transport of life from one planet to another within the solar system (interplanetary panspermia) or even between different planetary systems (interstellar panspermia). The main factor for the probability of interstellar panspermia is the average density of stellar systems containing habitable planets. The combination of recent results for the formation rate of Earth-like planets with our estimations of extrasolar habitable zones allows us to determine the number of habitable planets in the Milky Way over cosmological time scales. We find that there was a maximum number of habitable planets around the time of Earth's origin. If at all, interstellar panspermia was most probable at that time and may have kick-started life on our planet.

Physical constraints on the likelihood of life on exoplanets

NASA Astrophysics Data System (ADS)

Lingam, Manasvi; Loeb, Abraham

2018-04-01

One of the most fundamental questions in exoplanetology is to determine whether a given planet is habitable. We estimate the relative likelihood of a planet's propensity towards habitability by considering key physical characteristics such as the role of temperature on ecological and evolutionary processes, and atmospheric losses via hydrodynamic escape and stellar wind erosion. From our analysis, we demonstrate that Earth-sized exoplanets in the habitable zone around M-dwarfs seemingly display much lower prospects of being habitable relative to Earth, owing to the higher incident ultraviolet fluxes and closer distances to the host star. We illustrate our results by specifically computing the likelihood (of supporting life) for the recently discovered exoplanets, Proxima b and TRAPPIST-1e, which we find to be several orders of magnitude smaller than that of Earth.

Prebiotic synthesis of adenine and amino acids under Europa-like conditions.

PubMed

Levy, M; Miller, S L; Brinton, K; Bada, J L

2000-06-01

In order to simulate prebiotic synthetic processes on Europa and other ice-covered planets and satellites, we have investigated the prebiotic synthesis of organic compounds from dilute solutions of NH4CN frozen for 25 years at -20 and -78 degrees C. In addition, the aqueous products of spark discharge reactions from a reducing atmosphere were frozen for 5 years at -20 degrees C. We find that both adenine and guanine, as well as a simple set of amino acids dominated by glycine, are produced in substantial yields under these conditions. These results indicate that some of the key components necessary for the origin of life may have been available on Europa throughout its history and suggest that the circumstellar zone where life might arise may be wider than previously thought.