General form of a cooperative gradual maximal covering location problem
NASA Astrophysics Data System (ADS)
Bagherinejad, Jafar; Bashiri, Mahdi; Nikzad, Hamideh
2018-07-01
Cooperative and gradual covering are two new methods for developing covering location models. In this paper, a cooperative maximal covering location-allocation model is developed (CMCLAP). In addition, both cooperative and gradual covering concepts are applied to the maximal covering location simultaneously (CGMCLP). Then, we develop an integrated form of a cooperative gradual maximal covering location problem, which is called a general CGMCLP. By setting the model parameters, the proposed general model can easily be transformed into other existing models, facilitating general comparisons. The proposed models are developed without allocation for physical signals and with allocation for non-physical signals in discrete location space. Comparison of the previously introduced gradual maximal covering location problem (GMCLP) and cooperative maximal covering location problem (CMCLP) models with our proposed CGMCLP model in similar data sets shows that the proposed model can cover more demands and acts more efficiently. Sensitivity analyses are performed to show the effect of related parameters and the model's validity. Simulated annealing (SA) and a tabu search (TS) are proposed as solution algorithms for the developed models for large-sized instances. The results show that the proposed algorithms are efficient solution approaches, considering solution quality and running time.
The use of a silicon sheet for gradual wound closure after fasciotomy.
Walker, Tobias; Gruler, Miriam; Ziemer, Gerhard; Bail, Dorothee H L
2012-06-01
We present a silicon sheet for temporary wound covering and gradual wound closure after open fasciotomy. Fasciotomy was performed in a total of 70 limbs with compartment syndrome (CS). The main etiology of CS was predominantly vascular. All patients were treated with a silicon sheet to cover the soft tissue defect and gradually reapproximate the skin margins. In 53% of the patients, a delayed final wound closure was achieved after a mean of 11.9 days. This method allows final closure of fasciotomy wounds without scar contractures, marginal necrosis, infection, or significant pain. Copyright © 2012 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cohen, A.D.; Raymond, R. Jr.; Thayer, G.
1987-08-01
A peat deposit occupying over 80 square kilometers, and averaging 8 meters in thickness, was discovered on the Caribbean coast of northwestern Panama near the town of Changuinola. This deposit occurs inland (behind) the present beach-barrier shoreline. It is thickest in the center and thins toward all edges (as if domed). The surface vegetation in the central regions consists primarily of ombrotrophic plants (especially sedges, grasses, Sphagnum, Sagittaria, and various scattered shrubs). Toward the edges, the deposit has a surface cover of more minerotrophic plants (such as swamp-forest trees, ferns, and palms). Petrographic/botanical analysis of the deposit with depth revealsmore » the presence of five peat types (swamp-forest, sedge-grass-fern, Sagittaria et al., Nymphaea et al., and Rhizophora). Typically peats of the thick, central portions of the deposit are very low in ash and sulfur (less than 2% ash and 0.3% sulfur). Ash contents tend to increase abruptly at the base and more gradually toward the edges of the deposit and sulfur contents increasing gradually toward the ocean and bay. Vertical and lateral variations in botanical, chemical, and physical properties of this deposit can be related to factors that have controlled: (1) the surrounding rocks and water chemistry; (2) the source vegetation; and (3) the environments in which these source ingredients were deposited. 3 refs., 10 figs.« less
ICESat: Ice, Cloud and Land Elevation Satellite
NASA Technical Reports Server (NTRS)
Zwally, Jay; Shuman, Christopher
2002-01-01
Ice exists in the natural environment in many forms. The Earth dynamic ice features shows that at high elevations and/or high latitudes,snow that falls to the ground can gradually build up tu form thick consolidated ice masses called glaciers. Glaciers flow downhill under the force of gravity and can extend into areas that are too warm to support year-round snow cover. The snow line, called the equilibrium line on a glacier or ice sheet, separates the ice areas that melt on the surface and become show free in summer (net ablation zone) from the ice area that remain snow covered during the entire year (net accumulation zone). Snow near the surface of a glacier that is gradually being compressed into solid ice is called firm.
Vuillemin, Aurèle; Horn, Fabian; Alawi, Mashal; Henny, Cynthia; Wagner, Dirk; Crowe, Sean A.; Kallmeyer, Jens
2017-01-01
Extracellular DNA is ubiquitous in soil and sediment and constitutes a dominant fraction of environmental DNA in aquatic systems. In theory, extracellular DNA is composed of genomic elements persisting at different degrees of preservation produced by processes occurring on land, in the water column and sediment. Extracellular DNA can be taken up as a nutrient source, excreted or degraded by microorganisms, or adsorbed onto mineral matrices, thus potentially preserving information from past environments. To test whether extracellular DNA records lacustrine conditions, we sequentially extracted extracellular and intracellular DNA from anoxic sediments of ferruginous Lake Towuti, Indonesia. We applied 16S rRNA gene Illumina sequencing on both fractions to discriminate exogenous from endogenous sources of extracellular DNA in the sediment. Environmental sequences exclusively found as extracellular DNA in the sediment originated from multiple sources. For instance, Actinobacteria, Verrucomicrobia, and Acidobacteria derived from soils in the catchment. Limited primary productivity in the water column resulted in few sequences of Cyanobacteria in the oxic photic zone, whereas stratification of the water body mainly led to secondary production by aerobic and anaerobic heterotrophs. Chloroflexi and Planctomycetes, the main degraders of sinking organic matter and planktonic sequences at the water-sediment interface, were preferentially preserved during the initial phase of burial. To trace endogenous sources of extracellular DNA, we used relative abundances of taxa in the intracellular DNA to define which microbial populations grow, decline or persist at low density with sediment depth. Cell lysis became an important additional source of extracellular DNA, gradually covering previous genetic assemblages as other microbial genera became more abundant with depth. The use of extracellular DNA as nutrient by active microorganisms led to selective removal of sequences with lowest GC contents. We conclude that extracellular DNA preserved in shallow lacustrine sediments reflects the initial environmental context, but is gradually modified and thereby shifts from its stratigraphic context. Discrimination of exogenous and endogenous sources of extracellular DNA allows simultaneously addressing in-lake and post-depositional processes. In deeper sediments, the accumulation of resting stages and sequences from cell lysis would require stringent extraction and specific primers if ancient DNA is targeted. PMID:28798742
NASA Astrophysics Data System (ADS)
Egerer, Sabine; Claussen, Martin; Reick, Christian; Stanelle, Tanja
2017-09-01
The abrupt change in North Atlantic dust deposition found in sediment records has been associated with a rapid large scale transition of Holocene Saharan landscape. We hypothesize that gradual changes in the landscape may have caused this abrupt shift in dust deposition either because of the non-linearity in dust activation or because of the heterogeneous distribution of major dust sources. To test this hypothesis, we investigate the response of North Atlantic dust deposition to a prescribed 1) gradual and spatially homogeneous decrease and 2) gradual southward retreat of North African vegetation and lakes during the Holocene using the aerosol-climate model ECHAM-HAM. In our simulations, we do not find evidence of an abrupt increase in dust deposition as observed in marine sediment records along the Northwest African margin. We conclude that such gradual changes in landscape are not sufficient to explain the observed abrupt changes in dust accumulation in marine sediment records. Instead, our results point to a rapid large-scale retreat of vegetation and lakes in the area of significant dust sources.
Monitoring Forest and Rangeland Change in the United States Using Landsat Time Series Data
NASA Astrophysics Data System (ADS)
Vogelmann, J.; Tolk, B.; Xian, G. Z.; Homer, C.
2011-12-01
The LANDFIRE project produces spatial data layers for fire management applications. As part of the project, 2000 vintage Landsat Thematic Mapper and Enhanced Thematic Mapper plus data sets were used to generate detailed vegetation type data sets for the entire United States. We are currently using several approaches to update this information, including incorporation of (1) Landsat-derived historic fire burn information, (2) forest harvest information from Landsat time series data using the Vegetation Change Tracker, and (3) data sets that capture subtle and gradual intra-state disturbances, such as those related to insects and disease as well as succession. The primary focus of this presentation will be on of the detection and characterization of gradual change occurring in forest and rangeland ecosystems, and how to incorporate this information in the LANDFIRE updating process. Landsat data acquired over the previous 25+ years are being used to assess status and trends of forest and rangeland condition. Current study areas are located in the southwestern US, western Nebraska, western Wyoming, western South Dakota, northeastern US and the central Appalachian Mountains. Trends of changing vegetation index values derived from Landsat time series data stacks are the foundation for the gradual change information being developed. Thus far we have found evidence of gradual systematic change in all areas that we have examined. Many of the conifer forests in the southwestern US are showing declining conditions related to insects and drought, and very few of the examined areas are showing evidence of increased canopy cover or greenness. While sagebrush communities are showing decreases in greenness related to fire, mining, and drought, few of these communities are showing evidence of increased greenness or "improving" conditions. However, there is evidence that some forest communities are expanding and that canopy cover density is increasing at some locations. In Nebraska, increases in canopy cover appear to be mostly related to expansion of eastern red cedar. In the White Mountains of New Hampshire, observed increases in forest canopy appear to be related to understory balsam fir expansion, most likely related to release of forest suppression resulting from the thinning of the upper forest canopy. Continued analyses of time series data using multi-spatial scenes and covering multiple years are required in order to develop accurate impressions and representations of the changing ecosystem patterns and trends that are occurring. The approach demonstrates that Landsat time series data can be used operationally for assessing gradual ecosystem change across large areas. This information complements the information derived from other time-series change detection used for LANDFIRE.
Evaluation of the Biodurability of Polyurethane-Covered Stent Using a Flow Phantom
Kim, Dong Hyun; Choi, Jung Ryul; Byun, Ju Nam; Kim, Young Chul; Ahn, Young Moo
2001-01-01
Objective To evaluate the biodurability of the covering material in retrievable metallic stents covered with polycarbonate polyurethane. Materials and Methods Using a peristaltic pump at a constant rate of 1ml/min, bile was recirculated from a reservoir through a long tube containing four stents. Each of these was removed from the system every two weeks and a radial tensile strength test and scanning electron microscopy (SEM) were performed. Each stent, removed at 2, 4, 6 and 8 weeks, was compared with a control stent not exposed to bile juice. Results Gross examination showed that stents were intact at 2 weeks, but at 4, 6 and 8 weeks cracks were observed. The size of these increased gradually in accordance with the duration of exposure, and at 8 weeks several large holes in the polyurethane membrane were evident. With regard to radial tensile strength, extension and peak load at break were 84.47% and 10.030 N/mm, 54.90% and 6.769 N/mm, 16.55% and 2.452 N/mm, 11.21% and 1.373 N/mm at 0, 2, 4 and 6 weeks, respectively. Scanning electron microscopy at 2 weeks revealed intermittent pitting and cracking, and examination at 4, 6 and 8 weeks showed that the size of these defects was gradually increasing. Conclusion When the polyurethane membrane was exposed to bile, biodegradation was first observed at week two and increased gradually according to the duration of exposure. PMID:11752974
David A. Marquis; Ted J. Grisez
1978-01-01
In 6- to 10-year-old clearcuts that had failed to regenerate naturally, fencing was erected to protect seedlings from deer browsing. The fencing allowed the gradual recovery of the forest cover. Small seedlings that otherwise would have been browsed continued to grow, and ground cover species such as Rubus, which reduced ferns and grasses that...
Effects of cover crops incorporation and nitrogen fertilization on N2O and CO2 emissions
NASA Astrophysics Data System (ADS)
Kandel, T. P.; Gowda, P. H.; Northup, B. K.; DuPont, J.; Somenahally, A. C.; Rocateli, A.
2017-12-01
In this study, we measured N2O and CO2 fluxes from plots planted to hairy vetch (winter cover crop) and broadleaf vetch (spring cover crop) as N sources for the following crabgrass (summer forage crop) in El Reno, Oklahoma, USA. Comparisons also included 0 and 60 kg ha-1 mineral N fertilizer supplied as dry urea. No significant N2O fluxes were observed during rapid growing periods of cover crops (March-April, 2017), however, large fluxes were observed after hairy vetch incorporation. Immediately after the hairy vetch biomass incorporation, large rainfall events were recorded. The fluxes subsided gradually with drying soil condition but were enhanced after every consecutive rainfall events. A rainfall induced flux measuring up to 8.2 kg N2O ha-1 day-1 was observed after 26 days of biomass incorporation. In total, 29 kg N2O ha-1 (18 kg N ha-1) was emitted within a month after biomass incorporation from hairy vetch plots. Growth of broadleaf vetch was poor and N2O fluxes were also lower. Similarly, plots fertilized with 60 kg N ha-1 had significant fluxes of N2O but the magnitude was much lower than the hairy vetch plots. Dynamics of N2O and CO fluxes correlated strongly. The results thus indicated that although cover crops may provide many environmental/agronomic benefits such as N fixation, soil carbon built-up, weed suppression and erosion control, high N2O emissions may dwarf these benefits.
Analysis and asynchronous detection of gradually unfolding errors during monitoring tasks
NASA Astrophysics Data System (ADS)
Omedes, Jason; Iturrate, Iñaki; Minguez, Javier; Montesano, Luis
2015-10-01
Human studies on cognitive control processes rely on tasks involving sudden-onset stimuli, which allow the analysis of these neural imprints to be time-locked and relative to the stimuli onset. Human perceptual decisions, however, comprise continuous processes where evidence accumulates until reaching a boundary. Surpassing the boundary leads to a decision where measured brain responses are associated to an internal, unknown onset. The lack of this onset for gradual stimuli hinders both the analyses of brain activity and the training of detectors. This paper studies electroencephalographic (EEG)-measurable signatures of human processing for sudden and gradual cognitive processes represented as a trajectory mismatch under a monitoring task. Time-locked potentials and brain-source analysis of the EEG of sudden mismatches revealed the typical components of event-related potentials and the involvement of brain structures related to cognitive control processing. For gradual mismatch events, time-locked analyses did not show any discernible EEG scalp pattern, despite related brain areas being, to a lesser extent, activated. However, and thanks to the use of non-linear pattern recognition algorithms, it is possible to train an asynchronous detector on sudden events and use it to detect gradual mismatches, as well as obtaining an estimate of their unknown onset. Post-hoc time-locked scalp and brain-source analyses revealed that the EEG patterns of detected gradual mismatches originated in brain areas related to cognitive control processing. This indicates that gradual events induce latency in the evaluation process but that similar brain mechanisms are present in sudden and gradual mismatch events. Furthermore, the proposed asynchronous detection model widens the scope of applications of brain-machine interfaces to other gradual processes.
The biodurability of covering materials for metallic stents in a bile flow phantom.
Bang, Byoung Wook; Jeong, Seok; Lee, Don Haeng; Lee, Jung Il; Lee, Se Chul; Kang, Sung-Gwon
2012-04-01
Covered biliary metal stents have been introduced for the purpose of overcoming tumor ingrowth and treatment of benign biliary stricture. The aim of this study was to evaluate the biodurability of three commercially available biliary metal stent covering materials [e-PTFE (expanded polytetrafluoroethylene), silicone, and polyurethane] in a bile flow phantom. By operation of a peristaltic pump, human bile was circulated continuously in an experimental perfusion system containing covered metal stents. Each stent was removed, respectively, 1, 2, 4, and 6 months after bile exposure. We performed a gross inspection of the covered stents. The covering membrane was detached from the stent and observed by scanning electron microscopy (SEM). Finally, we measured tensile and tear strength of the membranes. Bile-staining of the membrane showed gradual progression after bile exposure; however, progress was the fastest in e-PTFE. SEM examination showed that the polyurethane surface was smooth, and the silicone surface was relatively smooth. However, e-PTFE had a rough and uneven surface. After bile exposure, there were no significant changes in polyurethane and silicone; however, biofilms and microcracks were observed in e-PTFE. In contrast to a gradual decrease of tensile/tear strength of polyurethane and silicone, those of e-PTFE showed a rapid reduction despite of the strongest baseline tensile and tear strength. e-PTFE tended to form biofilms more frequently than polyurethane and silicone during bile exposure. e-PTFE seemed to be less durable than silicone and polyurethane, however, as clinically applicable material because of strong absolute tensile/tear strengths.
NASA Astrophysics Data System (ADS)
Marson, Juliana M.; Myers, Paul G.; Hu, Xianmin
2017-04-01
The Atlantic Meridional Overturning Circulation (AMOC) is well known for carrying heat from low to high latitudes, moderating local temperatures. Numerical studies have examined the AMOC's variability under the influence of freshwater input to subduction and deep convections sites. However, an important source of freshwater has often been overlooked or misrepresented: icebergs. While liquid runoff decreases the ocean salinity near the coast, icebergs are a gradual and remote source of freshwater - a difference that affects sea ice cover, temperature, and salinity distribution in ocean models. Icebergs originated from the Greenland ice sheet, in particular, can affect the subduction process in Labrador Sea by decreasing surface water density. Our study aims to evaluate the distribution of icebergs originated from Greenland and their contribution to freshwater input in the North Atlantic. To do that, we use an interactive iceberg module coupled with the Nucleus for European Modelling of the Ocean (NEMO v3.4), which will calve icebergs from Greenland according to rates established by Bamber et al. (2012). Details on the distribution and trajectory of icebergs within the model may also be of use for understanding potential navigation threats, as shipping increases in northern waters.
Observed climate variability over Chad using multiple observational and reanalysis datasets
NASA Astrophysics Data System (ADS)
Maharana, Pyarimohan; Abdel-Lathif, Ahmat Younous; Pattnayak, Kanhu Charan
2018-03-01
Chad is the largest of Africa's landlocked countries and one of the least studied region of the African continent. The major portion of Chad lies in the Sahel region, which is known for its rapid climate change. In this study, multiple observational datasets are analyzed from 1950 to 2014, in order to examine the trend of precipitation and temperature along with their variability over Chad to understand possible impacts of climate change over this region. Trend analysis of the climatic fields has been carried out using Mann-Kendall test. The precipitation over Chad is mostly contributed during summer by West African Monsoon, with maximum northward limit of 18° N. The Atlantic Ocean as well as the Mediterranean Sea are the major source of moisture for the summer rainfall over Chad. Based on the rainfall time series, the entire study period has been divided in to wet (1950 to 1965), dry (1966 to 1990) and recovery period (1991 to 2014). The rainfall has decreased drastically for almost 3 decades during the dry period resulted into various drought years. The temperature increases at a rate of 0.15 °C/decade during the entire period of analysis. The seasonal rainfall as well as temperature plays a major role in the change of land use/cover. The decrease of monsoon rainfall during the dry period reduces the C4 cover drastically; this reduction of C4 grass cover leads to increase of C3 grass cover. The slow revival of rainfall is still not good enough for the increase of shrub cover but it favors the gradual reduction of bare land over Chad.
Mapping Coastal Wetland Change in Louisiana's Gulf Coast
Tidal wetlands and estuaries carry out several specific and unique ecosystem functions, which provide humans with goods and services that contribute to their wellbeing. In areas of natural adjacent land cover, tidal marshes can incrementally move inland as sea levels gradually r...
[Four-stage gradual expanding approach of problem based learning in otorhinolaryngology].
Kong, Weijia; Wang, Yanjun; Yue, Jianxin; Chen, Jianjun; Peng, Yixiang; Zhang, Sulin; Zhang, Xiaomeng
2008-08-01
The aim of the study is to cover the shortages of PBL, such as time-consuming, abstract, lacking of the course of clinic practice, and to introduce PBL to the teaching of otorhinolaryngology. By the improvement of the international classic teaching model of PBL, we put forward "four-stage gradual expanding approach of PBL" and establish "four-stage gradual expanding approach of PBL in otorhinolaryngology". Through the four stages of watching PBL, simulation PBL, internship PBL, practice PBL, we have accomplished the organic integration of theory teaching and clinical practice. This teaching method is more adaptive to the teaching of otorhinolaryngology, and it can help the medicine students to establish the whole concept of medicine and can stimulate them to form the good habits of self-regulated learning and life-long learning efficiently.
NASA Astrophysics Data System (ADS)
Haraldsson, Hörður V.; Ólafsdóttir, Rannveig
2003-09-01
Iceland is facing severe land degradation in many parts of the country. This study aims to increase the understanding of the complex interactions and interconnectivity between the critical factors that help maintain the land degradation processes in sub-arctic environments. A holistic approach in the form of a causal loop diagram (CLD) is applied for diagnosing the influencing factors. To further study the relationship between vegetation cover and its degradation, a dynamic model that uses a long-term temperature data as the main indicator function is constructed to simulate potential vegetation cover during the Holocene. The results depict an oscillating vegetation cover. Gradual degradation in potential vegetation cover begins ca. 3000 BP and accelerates greatly after ca. 2500 BP. From the time of the Norse settlement in the latter halve of the 9th century to present time, the simulated vegetation cover retreats ca. 25% in relation to climatic cooling.
Chen, Hsi-Chao; Yang, Chi-Hao
2014-05-10
The effects of different pitch and angle of gradual-triangle lenticular lens for the point-blank LED fog lamp were investigated under the standard of ECE R19. The novel LED fog lamp was assembled from a point-blank LED light source, a parabolic reflector, and a gradual-triangle lenticular lens. Light tracing analysis was used for the design of the gradual-triangle lenticular lens. The pitch, which varied from 1 to 6 mm, and the apex angle, which changed from 5 to 32 deg, were both investigated in regard to the gradual-triangle lenticular lens. The optimum pitch was 5 mm, and the efficiency of the lamp system and lenticular lens could reach 93% and 98.1% by simulation, respectively. The results of experiment had over 94%, which is similar to that of simulation by normalized cross correlation (NCC) for the light intensity.
Partitioning Evapotranspiration into Green and Blue Water Sources in the Conterminous United States.
Velpuri, Naga Manohar; Senay, Gabriel B
2017-07-21
In this study, we combined two 1 km actual evapotranspiration datasets (ET), one obtained from a root zone water balance model and another from an energy balance model, to partition annual ET into green (rainfall-based) and blue (surface water/groundwater) sources. Time series maps of green water ET (GWET) and blue water ET (BWET) are produced for the conterminous United States (CONUS) over 2001-2015. Our results indicate that average green and blue water for all land cover types in CONUS accounts for nearly 70% and 30% of the total ET, respectively. The ET in the eastern US arises mostly from GWET, and in the western US, it is mostly BWET. Analysis of the BWET in the 16 irrigated areas in CONUS revealed interesting results. While the magnitude of the BWET gradually showed a decline from west to east, the increase in coefficient of variation from west to east confirmed greater use of supplemental irrigation in the central and eastern US. We also established relationships between different hydro-climatology zones and their blue water requirements. This study provides insights on the relative contributions and the spatiotemporal dynamics of GWET and BWET, which could lead to improved water resources management.
33 CFR 329.13 - Geographic limits: Shifting boundaries.
Code of Federal Regulations, 2011 CFR
2011-07-01
... area will remain “navigable in law,” even though no longer covered with water, whenever the change has...: Shifting boundaries. Permanent changes of the shoreline configuration result in similar alterations of the boundaries of the navigable waters of the United States. Thus, gradual changes which are due to natural...
33 CFR 329.13 - Geographic limits: Shifting boundaries.
Code of Federal Regulations, 2013 CFR
2013-07-01
... area will remain “navigable in law,” even though no longer covered with water, whenever the change has...: Shifting boundaries. Permanent changes of the shoreline configuration result in similar alterations of the boundaries of the navigable waters of the United States. Thus, gradual changes which are due to natural...
33 CFR 329.13 - Geographic limits: Shifting boundaries.
Code of Federal Regulations, 2014 CFR
2014-07-01
... area will remain “navigable in law,” even though no longer covered with water, whenever the change has...: Shifting boundaries. Permanent changes of the shoreline configuration result in similar alterations of the boundaries of the navigable waters of the United States. Thus, gradual changes which are due to natural...
Changes in Landscape Greenness and Climatic Factors over 25 Years (1989–2013) in the USA
Monitoring and quantifying changes in vegetation cover over large areas using remote sensing can be achieved using the Normalized Difference Vegetation Index (NDVI), an indicator of greenness. However, distinguishing gradual shifts in NDVI (e.g. climate change) versus direct and ...
Chen, Xuexia; Giri, Chandra; Vogelmann, James
2012-01-01
Land cover is the biophysical material on the surface of the earth. Land-cover types include grass, shrubs, trees, barren, water, and man-made features. Land cover changes continuously. The rate of change can be either dramatic and abrupt, such as the changes caused by logging, hurricanes and fire, or subtle and gradual, such as regeneration of forests and damage caused by insects (Verbesselt et al., 2001). Previous studies have shown that land cover has changed dramatically during the past sevearal centuries and that these changes have severely affected our ecosystems (Foody, 2010; Lambin et al., 2001). Lambin and Strahlers (1994b) summarized five types of cause for land-cover changes: (1) long-term natural changes in climate conditions, (2) geomorphological and ecological processes, (3) human-induced alterations of vegetation cover and landscapes, (4) interannual climate variability, and (5) human-induced greenhouse effect. Tools and techniques are needed to detect, describe, and predict these changes to facilitate sustainable management of natural resources.
DOT National Transportation Integrated Search
1992-01-01
Fearful that inflation and the gradual erosion of federal support for highway safety programs were undermining Virginia's historic position of national leadership in highway safety; management directed a study of potential sources of new revenue for ...
Wang, Jiawei; Zhou, Yuqi; Sun, Xiaodong; Ma, Qingyu; Zhang, Dong
2016-04-01
As a multiphysics imaging approach, magnetoacoustic tomography with magnetic induction (MAT-MI) works on the physical mechanism of magnetic excitation, acoustic vibration, and transmission. Based on the theoretical analysis of the source vibration, numerical studies are conducted to simulate the pathological changes of tissues for a single-layer cylindrical conductivity gradual-varying model and estimate the strengths of sources inside the model. The results suggest that the inner source is generated by the product of the conductivity and the curl of the induced electric intensity inside conductivity homogeneous medium, while the boundary source is produced by the cross product of the gradient of conductivity and the induced electric intensity at conductivity boundary. For a biological tissue with low conductivity, the strength of boundary source is much higher than that of the inner source only when the size of conductivity transition zone is small. In this case, the tissue can be treated as a conductivity abrupt-varying model, ignoring the influence of inner source. Otherwise, the contributions of inner and boundary sources should be evaluated together quantitatively. This study provide basis for further study of precise image reconstruction of MAT-MI for pathological tissues.
Long-term impacts of land cover changes on stream channel loss.
Julian, Jason P; Wilgruber, Nicholas A; de Beurs, Kirsten M; Mayer, Paul M; Jawarneh, Rana N
2015-12-15
Land cover change and stream channel loss are two related global environmental changes that are expanding and intensifying. Here, we examine how different types and transitions of land cover change impact stream channel loss across a large urbanizing watershed. We present historical land cover in the 666-km(2) Lake Thunderbird watershed in central Oklahoma (USA) over a 137 year period and coinciding stream channel length changes for the most recent 70 years of this period. Combining these two datasets allowed us to assess the interaction of land cover changes with stream channel loss. Over this period, the upper third of the watershed shifted from predominantly native grassland to an agricultural landscape, followed by widespread urbanization. The lower two-thirds of the watershed changed from a forested landscape to a mosaic of agriculture, urban, forest, and open water. Most channel length lost in the watershed over time was replaced by agriculture. Urban development gradually increased channel loss and disconnection from 1942 to 2011, particularly in the headwaters. Intensities of channel loss for both agriculture and urban increased over time. The two longest connected segments of channel loss came from the creation of two large impoundments, resulting in 46 km and 25 km of lost stream channel, respectively. Overall, the results from this study demonstrate that multiple and various land-use changes over long time periods can lead to rapid losses of large channel lengths as well as gradual (but increasing) losses of small channel lengths across all stream sizes. When these stream channel losses are taken into account, the environmental impacts of anthropogenic land-use change are compounded. Copyright © 2015 Elsevier B.V. All rights reserved.
Tracking Trends in Fractional Forest Cover Change using Long Term Data from AVHRR and MODIS
NASA Astrophysics Data System (ADS)
Kim, D. H.; DiMiceli, C.; Sohlberg, R. A.; Hansen, M.; Carroll, M.; Kelly, M.; Townshend, J. R.
2014-12-01
Tree cover affects terrestrial energy and water exchanges, photosynthesis and transpiration, net primary production, and carbon and nutrient fluxes. Accurate and long-term continuous observation of tree cover change is critical for the study of the gradual ecosystem change. Tree cover is most commonly inferred from categorical maps which may inadequately represent within-class heterogeneity for many analyses. Alternatively, Vegetation Continuous Fields data measures fractions or proportions of pixel area. Recent development in remote sensing data processing and cross sensor calibration techniques enabled the continuous, long-term observations such as Land Long-Term Data Records. Such data products and their surface reflectance data have enhanced the possibilities for long term Vegetation Continuous Fields data, thus enabling the estimation of long term trend of fractional forest cover change. In this presentation, we will summarize the progress in algorithm development including automation of training selection for deciduous and evergreen forest, the preliminary results, and its future applications to relate trends in fractional forest cover change and environmental change.
Remote Sensing of Climate-Driven Range Shifts of Vegetation across North American Mountain Ranges
NASA Astrophysics Data System (ADS)
Kendrick, J. A.; Sax, D. F.; Kellner, J. R.
2015-12-01
Global climate change is driving shifts in local environmental conditions, and many organisms are projected to become poorly adapted to their current ranges. Some species may respond by gradually shifting their range limits to track environmental change. This adaptation strategy is expected to be most feasible in regions with sharp climatic gradients, such as mountain ranges. However, the extent to which this process is taking place is poorly understood, and some evidence suggests that shifts upwards in elevation might be more difficult than expected. Direct empirical evidence of range shifts in response to recent climate change could inform models and conservation strategies. Here we used Monte Carlo spectral unmixing of Landsat surface reflectance data to characterize changes in vegetation cover across major North American mountain ranges over the past 30 years. This approach allows us to observe changes in photosynthetic and nonphotosynthetic vegetation as well as absolute change in vegetation cover. We found evidence of a gradual increase in total vegetation cover at increasing elevations, but this pattern varied in its strength both within and among mountain ranges. We also observed more dramatic changes in vegetation type which differed strongly between regions with different climates. Our analysis shows that upslope range shift is a possible climate response in many cases, but that this process does not occur uniformly.
Grain size and shape analysis of the AD 1226 tephra layer, Reykjanes volcanic system
NASA Astrophysics Data System (ADS)
Ösp Magnúsdóttir, Agnes; Höskuldsson, Ármann; Larsen, Guðrún; Tumi Guðmunsson, Magnús; Sigurgeirsson, Magnús Á.
2014-05-01
Recent explosive eruptions in Iceland have drawn attention to long range tephra transport in the atmosphere. In Iceland tephra forming explosion eruptions are frequent, due to abundance of water. However, the volcanism on the island is principally basaltic. Volcanism along the Reykjanes Peninsula is divided into five distinct volcanic systems. Volcano-tectonic activity within these systems is periodic, with recurrence intervals in the range of 1 ka. Last volcano-tectonic sequence began around AD 940, shortly after settlement of Iceland, and lasted through AD 1340. During this period activity was characterized by basaltic fissure eruptions. Furthermore, this activity period on the Reykjanes peninsula began within the eastern most volcanic system and gradually moved towards the west across the peninsula. The 1226 eruption was a basaltic fissure eruption with in the Reykjanes volcanic system. The eruption began on land and gradually progressed towards the SW until the volcanic fissure extended into the sea. Water-magma interaction changed the eruption from effusive into explosive forming the largest tephra layer on the peninsula. Due to its close proximity to the Keflavik international airport and that of the capital of Iceland it is important to get an insight into, the characteristics, generation and distribution of such tephra deposits. In this eruption the tephra produced had an approximate volume of 0.1 km3 and covered an area of some 3500 km2 within the 0.5 cm isopach. Total grain size distribution of this tephra layer will be presented along with analysis of principal grain shapes of the finer portion of the tephra layer as a function of distance from the source. The tephra grain size is dominated by particles finer than 1 millimeter with an almost complete absence of large grains independent of distance from the source. Comprehensive understanding of the characteristics of tephra generated in this eruption can help us to understand hazards posed by future eruptions of similar nature in the area.
Adjustable Lid Aids Silicon-Ribbon Growth
NASA Technical Reports Server (NTRS)
Mchugh, J. P.; Steidensticker, R. G.; Duncan, C. S.
1985-01-01
Closely-spaced crucible cover speeds up solidification. Growth rate of dendritic-web silicon ribbon from molten silicon increased by controlling distance between crucible susceptor lid and liquid/solid interface. Lid held in relatively high position when crucible newly filled with chunks of polycrystalline silicon. As silicon melts and forms pool of liquid at lower level, lid gradually lowered.
Frequency-Accommodating Manchester Decoder
NASA Technical Reports Server (NTRS)
Vasquez, Mario J.
1988-01-01
No adjustment necessary to cover a 10:1 frequency range. Decoding circuit converts biphase-level pulse-code modulation to nonreturn-to-zero (NRZ)-level pulse-code modulation plus clock signal. Circuit accommodates input data rate of 50 to 500 kb/s. Tracks gradual changes in rate automatically, eliminating need for extra circuits and manual switching to adjust to different rates.
Shift in fire-ecosystems and weather changes
Bongani Finiza
2013-01-01
During recent decades too much focus fell on fire suppression and fire engineering methods. Little attention has been given to understanding the shift in the changing fire weather resulting from the global change in weather patterns. Weather change have gradually changed the way vegetation cover respond to fire occurrence and brought about changes in fire behavior and...
Bioinspired air-retaining nanofur for drag reduction.
Kavalenka, Maryna N; Vüllers, Felix; Lischker, Simone; Zeiger, Claudia; Hopf, Andreas; Röhrig, Michael; Rapp, Bastian E; Worgull, Matthias; Hölscher, Hendrik
2015-05-27
Bioinspired nanofur, covered by a dense layer of randomly distributed high aspect ratio nano- and microhairs, possesses superhydrophobic and air-retaining properties. Nanofur is fabricated using a highly scalable hot pulling method in which softened polymer is elongated with a heated sandblasted plate. Here we investigate the stability of the underwater air layer retained by the irregular nanofur topography by applying hydraulic pressure to the nanofur kept underwater, and evaluate the gradual changes in the air-covered area. Furthermore, the drag reduction resulting from the nanofur air retention is characterized by measuring the pressure drop across channels with and without nanofur.
Monitoring snow cover and its effect on runoff regime in the Jizera Mountains
NASA Astrophysics Data System (ADS)
Kulasova, Alena
2015-04-01
The Jizera Mountains in the northern Bohemia are known by its rich snow cover. Winter precipitation represents usually a half of the precipitation in the hydrological year. Gradual snow accumulation and melt depends on the course of the particular winter period, the topography of the catchments and the type of vegetation. During winter the snow depth, and especially the snow water equivalent, are affected by the changing character of the falling precipitation, air and soil temperatures and the wind. More rapid snowmelt occurs more on the slopes without forest oriented to the South, while a gradual snowmelt occurs on the locations turned to the North and in forest. Melting snow recharges groundwater and affects water quality in an important way. In case of extreme situation the snowmelt monitoring is important from the point of view of flood protection of communities and property. Therefore the immediate information on the amount of water in snow is necessary. The way to get this information is the continuous monitoring of the snow depth and snow water equivalent. In the Jizera Mountains a regular monitoring of snow cover has been going on since the end of the 19th century. In the 80s of the last century the Jizera Mountains were affected by the increased fallout of pollutants in the air. There followed a gradual dieback of the forest cover and cutting down the upper part of the ridges. In order to get data for the quantification of runoff regime changes in the changing natural environment, the Czech Hydrometeorological Institute (CHMI) founded in the upper part of the Mountains several experimental catchments. One of the activities of the employees of the experimental basis is the regular measurement of snow cover at selected sites from 1982 up to now. At the same time snow cover is being observed using snow pillows, where its mass is monitored with the help of pressure sensors. In order to improve the reliability of the continuous measurement of the snow water equivalent the LDSMS (Libor Danes Snow Measurement System) which uses weighing sensors has been developed. The system contains a novel device precluding the snowbridging (protected by a utility model). Data from manual and automatic measurements are transmitted to the central forecasting service of CHMI in Prague - Komorany (CPP) and to regional forecasting branches (RPP), where they are one of the inputs of the hydrological forecasting models. The contribution deals with the results of the manual snow measurement during the dieback of forest and now, in comparison with the automatic snow measurement in the experimental catchments of CHMI Uhlirska, Jezdecka and with the effect of snowmelt on the water level in the streams.
Seepage through a hazardous-waste trench cover
Healy, R.W.
1989-01-01
Water movement through a waste-trench cover under natural conditions at a low-level radioactive waste disposal site in northwestern Illinois was studied from July 1982 to June 1984, using tensiometers, a moisture probe, and meteorological instruments. Four methods were used to estimate seepage: the Darcy, zero-flux plane, surface-based water-budget, and groundwater-based water-budget methods. Annual seepage estimates ranged from 48 to 216 mm (5-23% of total precipitation), with most seepage occurring in spring. The Darcy method, although limited in accuracy by uncertainty in hydraulic conductivity, was capable of discretizing seepage in space and time and indicated that seepage varied by almost an order of magnitude across the width of the trench. Lowest seepage rates occurred near the center of the cover, where seepage was gradual. Highest rates occurred along the edge of the cover, where seepage was highly episodic, with 84% of the total there being traced to wetting fronts from 28 individual storms. Limitations of the zero-flux-plane method were severe enough for the method to be judged inappropriate for use in this study.Water movement through a waste-trench cover under natural conditions at a low-level radioactive waste disposal site in northwestern Illinois was studied from July 1982 to June 1984, using tensiometers, a moisture probe, and meteorological instruments. Four methods were used to estimate seepage: the Darcy, zero-flux plane, surface-based water-budget, and groundwater-based water-budget methods. Annual seepage estimates ranged from 48 to 216mm (5-23% of total precipitation), with most seepage occurring in spring. The Darcy method, although limited in accuracy by uncertainty in hydraulic conductivity, was capable of discretizing seepage in space and time and indicated that seepage varied by almost an order of magnitude across the width of the trench. Lowest seepage rates occurred near the center of the cover, where seepage was gradual. Highest rates occurred along the edge of the cover, where seepage was highly episodic, with 84% of the total there being traced to wetting fronts from 28 individual storms. Limitations of the zero-flux-plane method were severe enough for the method to be judged inappropriate for use in this study.
NASA Technical Reports Server (NTRS)
Cane, H. V.; Reames, D. V.; Von Rosenvinge, T. T.
1991-01-01
The abundances of elements in large solar energetic-particle events in the energy range of 2-12 MeV per nucleon are examined. It is confirmed that the abundances relative to mean values vary approximately monotonically as a function of mass, except for He-4; some events show a gradual depletion of heavy ions, whereas a small number displays a gradual increase. A further organization of abundance data is shown, which depends on the longitude of the source region. Enhancements in Fe/C and other heavy elements relative to C occur when source regions are near west 60 deg; the enhancements are attributed to the sampling of a flare-heated material. Depletions of these elements are found to be greatest for source regions near central meridian; they are matched by a steepening of the spectrum and can be understood in terms of diffusive shock acceleration.
NASA Astrophysics Data System (ADS)
Xiao, X.; Zhao, M.; Knudsen, K. L.; Eiriksson, J.; Gudmundsdottir, E. R.; Jiang, H.; Guo, Z.
2017-12-01
Sea ice, prevailing in the polar region and characterized by distinct seasonal and interannual variability, plays a pivotal role in Earth's climate system (Thomas and Dieckmann, 2010). Studies of spatial and temporal changes in modern and past sea-ice occurrence may help to understand the processes controlling the recent decrease in Arctic sea-ice cover. Here, we determined the concentrations of sea-ice diatom-derived biomarker "IP25" (monoene highly-branched isoprenoid with 25 carbon atom; Belt et al., 2007), phytoplankton-derived biomarker brassicasterol and terrigenous biomarker long-chain n-alkanols in a sediment core from the North Icelandic shelf to reconstruct the high-resolution sea-ice variability and the organic-matter sources during the past 15,000 years. During the Bølling/Allerød, the North Icelandic shelf was characterized by extensive spring sea-ice cover linked to reduced flow of warm Atlantic Water and dominant Polar water influence; the input of terrestrial and sea-ice organic matters was high while the marine organic matter derived from phytoplankton productivity was low. Prolonged sea-ice cover with occasional occurrence of seasonal sea ice prevailed during the Younger Dryas interrupted by a brief interval of enhanced Irminger Current; the organic carbon input from sea-ice productivity, terrestrial matter and phytoplankton productivity all decreased. The seasonal sea ice decreased gradually from the Younger Dryas to the onset of the Holocene corresponding to increasing insolation. Therefore, the sea-ice productivity decreased but the phytoplankton productivity increased during this time interval. The biomarker records from this sediment core give insights into the variability in sea ice and organic-carbon sources in the Arctic marginal area during the last deglacial and Holocene. References Belt, S.T., Massé, G., Rowland, S.J., Poulin, M., Michel, C., LeBlanc, B., 2007. A novel chemical fossil of palaeo sea ice: IP25. Org. Geochem. 38, 16-27. Knudsen, K.L. and Eiriksson, J., 2002. Application of tephrochronology to the timing and correlation of palaeoceanographic events recorded in Holocene and Late Glacial shelf sediments off North Iceland. Marine Geology 191, 165-188. Thomas, D. N. and Dieckmann, G. S., 2010. Sea Ice, Blackwell Publ., Oxford, U. K.
Increased nitrous oxide emissions from Arctic peatlands after permafrost thaw
Marushchak, Maija E.; Lamprecht, Richard E.; Jackowicz-Korczyński, Marcin; Lindgren, Amelie; Mastepanov, Mikhail; Granlund, Lars; Christensen, Torben R.; Tahvanainen, Teemu; Martikainen, Pertti J.; Biasi, Christina
2017-01-01
Permafrost in the Arctic is thawing, exposing large carbon and nitrogen stocks for decomposition. Gaseous carbon release from Arctic soils due to permafrost thawing is known to be substantial, but growing evidence suggests that Arctic soils may also be relevant sources of nitrous oxide (N2O). Here we show that N2O emissions from subarctic peatlands increase as the permafrost thaws. In our study, the highest postthaw emissions occurred from bare peat surfaces, a typical landform in permafrost peatlands, where permafrost thaw caused a fivefold increase in emissions (0.56 ± 0.11 vs. 2.81 ± 0.6 mg N2O m−2 d−1). These emission rates match those from tropical forest soils, the world’s largest natural terrestrial N2O source. The presence of vegetation, known to limit N2O emissions in tundra, did decrease (by ∼90%) but did not prevent thaw-induced N2O release, whereas waterlogged conditions suppressed the emissions. We show that regions with high probability for N2O emissions cover one-fourth of the Arctic. Our results imply that the Arctic N2O budget will depend strongly on moisture changes, and that a gradual deepening of the active layer will create a strong noncarbon climate change feedback. PMID:28559346
Multi-Scale Fractal Analysis of Image Texture and Pattern
NASA Technical Reports Server (NTRS)
Emerson, Charles W.; Lam, Nina Siu-Ngan; Quattrochi, Dale A.
1999-01-01
Analyses of the fractal dimension of Normalized Difference Vegetation Index (NDVI) images of homogeneous land covers near Huntsville, Alabama revealed that the fractal dimension of an image of an agricultural land cover indicates greater complexity as pixel size increases, a forested land cover gradually grows smoother, and an urban image remains roughly self-similar over the range of pixel sizes analyzed (10 to 80 meters). A similar analysis of Landsat Thematic Mapper images of the East Humboldt Range in Nevada taken four months apart show a more complex relation between pixel size and fractal dimension. The major visible difference between the spring and late summer NDVI images is the absence of high elevation snow cover in the summer image. This change significantly alters the relation between fractal dimension and pixel size. The slope of the fractal dimension-resolution relation provides indications of how image classification or feature identification will be affected by changes in sensor spatial resolution.
Removable Type Expansion Bolt Innovative Design
NASA Astrophysics Data System (ADS)
Wang, Feng-Lan; Zhang, Bo; Gao, Bo; Liu, Yan-Xin; Gao, Bo
2016-05-01
Expansion bolt is a kind of the most common things in our daily life. Currently, there are many kinds of expansion bolts in the market. However, they have some shortcomings that mainly contain underuse and unremovement but our innovation of design makes up for these shortcomings very well. Principle of working follows this: expansion tube is fixed outside of bolt, steel balls and expansion covers are fixed inside. Meanwhile, the steel balls have 120° with each other. When using it ,expansion cover is moved in the direction of its internal part. So the front part of expansion bolt cover is increasingly becoming big and steel halls is moved outside. Only in this way can it be fixed that steel balls make expansion tube expand. When removing them, expansion bolt is moved outside. So the front part of expansion bolt cover is gradually becoming small and steel balls moves inside, after expansion tube shrinks, we can detach them.
Multi-Scale Fractal Analysis of Image Texture and Pattern
NASA Technical Reports Server (NTRS)
Emerson, Charles W.; Lam, Nina Siu-Ngan; Quattrochi, Dale A.
1999-01-01
Analyses of the fractal dimension of Normalized Difference Vegetation Index (NDVI) images of homogeneous land covers near Huntsville, Alabama revealed that the fractal dimension of an image of an agricultural land cover indicates greater complexity as pixel size increases, a forested land cover gradually grows smoother, and an urban image remains roughly self-similar over the range of pixel sizes analyzed (10 to 80 meters). A similar analysis of Landsat Thematic Mapper images of the East Humboldt Range in Nevada taken four months apart show a more complex relation between pixel size and fractal dimension. The major visible difference between the spring and late summer NDVI images of the absence of high elevation snow cover in the summer image. This change significantly alters the relation between fractal dimension and pixel size. The slope of the fractal dimensional-resolution relation provides indications of how image classification or feature identification will be affected by changes in sensor spatial resolution.
Evolution of the soil cover of soccer fields
NASA Astrophysics Data System (ADS)
Belobrov, V. P.; Zamotaev, I. V.
2014-04-01
A soccer field can be considered a soil-like technogenic formation (STF). According to the theory of soil cover patterns, the artificially constructed (anthropogenic) soil cover of a soccer field is an analogue of a relatively homogeneous elementary soil area. However, the spatial homogeneity of the upper part (50-80 cm) of the STF of soccer fields is unstable and is subjected to gradual transformation under the impact of pedogenetic processes, agrotechnical loads, and mechanical loads during the games. This transformation is favored by the initial heterogeneity of the deep (buried) parts of the STF profile. The technogenic factors and elementary pedogenetic processes specify the dynamic functioning regime of the STF. In 50-75 years, the upper part of the STF is transformed into soil-like bodies with properties close to those in zonal soils. Certain micro- and nanopatterns of the soil cover are developed within the field creating its spatial heterogeneity.
The differentiation profile of the epithelium of the human lip.
Barrett, A W; Morgan, M; Nwaeze, G; Kramer, G; Berkovitz, B K B
2005-04-01
The aim of this study was to analyse the immunohistochemical differentiation profile of the stratified squamous epithelium of the adult human lip. Full-thickness lower lips taken from 31 cadavers were analysed. Sections were stained with haematoxylin and eosin, periodic acid-Schiff (PAS), cytokeratins (CK), loricrin, involucrin, profilaggrin and filaggrin. The stratified squamous epithelium covering the lip could be divided into: (i) appendage-bearing, orthokeratinised epidermis; (ii) orthokeratinised vermilion which had a more prominent rete pattern than the epidermis; (iii) parakeratinised, PAS-positive intermediate zone; and (iv) non- or parakeratinised labial mucosal epithelium. Epithelial thickness increased gradually from the skin to the mucosal aspect. The CK pattern changed across the intermediate zone, with gradual loss of CK 1 and 10 from the skin, and CK 4, 13 and 19 from the mucosal, aspect. CK 5 and 14 were consistently expressed basally, and variably expressed suprabasally. Apart from labelling Merkel cells, CK 8, 18 and 20 were negative. Involucrin, which was present at all sites, was restricted to the stratum granulosum in skin, but extended into the stratum spinosum, and gradually into parabasal keratinocytes, across the vermilion and mucosa. Loricrin, profilaggrin and filaggrin were present in the stratum granulosum of orthokeratinised sites, but expression was abruptly lost at the junction between the vermilion and the intermediate zone. In conclusion, the phenotype of the stratified squamous epithelium covering the lip changes at, or across, the intermediate zone of the adult vermilion. It is possible that changes in the composition of the stratified squamous epithelium affect the colour of the vermilion.
NASA Astrophysics Data System (ADS)
Seleem, T.; Stergiopoulos, V.; Kourkouli, P.; Perrou, T.; Parcharidis, Is.
2017-10-01
The main scope of this study is to investigate the potential correlation between land cover and ground vulnerability over Alexandria city, Egypt. Two different datasets for generating ground deformation and land cover maps were used. Hence, two different approaches were followed, a PSI approach for surface displacement mapping and a supervised classification algorithm for land cover/use mapping. The interferometric results show a gradual qualitative and quantitative differentiation of ground deformation from East to West of Alexandria government. We selected three regions of interest, in order to compare the obtained interferometric results with the different land cover types. The ground deformation may be resulted due to different geomorphic and geologic factors encompassing the proximity to the active deltaic plain of the Nile River, the expansion of the urban network within arid regions of recent deposits, the urban density increase, and finally the combination of the above mentioned parameters.
Simulating the Gradually Deteriorating Performance of an RTG
NASA Technical Reports Server (NTRS)
Wood, Eric G.; Ewell, Richard C.; Patel, Jagdish; Hanks, David R.; Lozano, Juan A.; Snyder, G. Jeffrey; Noon, Larry
2008-01-01
Degra (now in version 3) is a computer program that simulates the performance of a radioisotope thermoelectric generator (RTG) over its lifetime. Degra is provided with a graphical user interface that is used to edit input parameters that describe the initial state of the RTG and the time-varying loads and environment to which it will be exposed. Performance is computed by modeling the flows of heat from the radioactive source and through the thermocouples, also allowing for losses, to determine the temperature drop across the thermocouples. This temperature drop is used to determine the open-circuit voltage, electrical resistance, and thermal conductance of the thermocouples. Output power can then be computed by relating the open-circuit voltage and the electrical resistance of the thermocouples to a specified time-varying load voltage. Degra accounts for the gradual deterioration of performance attributable primarily to decay of the radioactive source and secondarily to gradual deterioration of the thermoelectric material. To provide guidance to an RTG designer, given a minimum of input, Degra computes the dimensions, masses, and thermal conductances of important internal structures as well as the overall external dimensions and total mass.
[XPS analysis of beads formed by fuse breaking of electric copper wire].
Wu, Ying; Meng, Qing-Shan; Wang, Xin-Ming; Gao, Wei; Di, Man
2010-05-01
The in-depth composition of beads formed by fuse breaking of the electric copper wire in different circumstances was studied by XPS with Ar+ ion sputtering. In addition, the measured Auger spectra and the calculated Auger parameters were compared for differentiation of the substances of Cu and Cu2O. Corresponding to the sputtering depth, the molten product on a bead induced directly by fuse breaking of the copper wire without cover may be distinguished as three portions: surface layer with a drastic decrease in carbon content; intermediate layer with a gentle change in oxygen content and gradually diminished carbon peak, and consisting of Cu2O; transition layer without Cu2O and with a rapid decrease in oxygen content. While the molten product on a bead formed by fuse breaking of the copper wire after its insulating cover had been burned out may be distinguished as two portions: surface layer with carbon content decreasing quickly; subsurface layer without Cu2O and with carbon and oxygen content decreasing gradually. Thus, it can be seen that there was an obvious interface between the layered surface product and the substrate for the first type of bead, while as to the second type of bead there was no interface. As a result, the presence of Cu2O and the quantitative results can be used to identify the molten product on a bead induced directly by fuse breaking of the copper wire without cover and the molten product on a bead formed by fuse breaking of the cupper wire after its insulating cover had been burned out, as a complementary technique for the judgments of fire cause.
Effect of emergent aquatic insects on bat foraging in a riparian forest.
Fukui, Dai; Murakami, Masashi; Nakano, Shigeru; Aoi, Toshiki
2006-11-01
1. Riparian zones serve several ecological functions for bats. They provide a source of prey and likely provide favourable structural habitats and shelter from predators. Many studies have shown that bats use the space above streams, ponds or riparian vegetation as feeding habitat. These studies, however, have never distinguished between the effects of habitat structure and prey availability on the foraging activities of bats. Such effects can only be distinguished by an experimental approach. We predicted that bat activity along a stream is influenced by the number of emerged aquatic insects. 2. We evaluated the response of terrestrial consumers, insectivorous bats, to changes in the abundance of emergent aquatic insects by conducting a manipulative field experiment. In a deciduous riparian forest in Japan, aquatic insect flux from the stream to the riparian zone was controlled with an insect-proof cover over a 1.2 km stream reach. 3. We estimated the abundance of emergent aquatic and flying terrestrial arthropods near the treatment and control reaches using Malaise traps. The foraging activity of bats was evaluated in both treatment and control reaches using ultrasonic detectors. 4. The insect-proof cover effectively reduced the flux of emergent aquatic insects to the riparian zone adjacent to the treatment reach. Adjacent to the control reach, adult aquatic insect biomass was highest in spring, and then decreased gradually. Terrestrial insect biomass increased gradually during the summer at both treatment and control reaches. 5. Foraging activity of bats was correlated with insect abundance. In spring, foraging activity of bats at the control reach was significantly greater than at the treatment reach, and increased at both sites with increasing terrestrial insect abundance. 6. Our result suggests that the flux of aquatic insects emerging from streams is one of the most important factors affecting the distribution of riparian-foraging bats. As is the case with other riparian consumers, resource subsidies from streams can directly enhance the performance or population density of riparian-dependent bats. To conserve and manage bat populations, it is important to protect not only forest ecosystems, but also adjacent aquatic systems such as streams.
NASA Astrophysics Data System (ADS)
Sadr, Alireza; Mandurah, Mona; Nakashima, Syozi; Shimada, Yasushi; Kitasako, Yuichi; Tagami, Junji; Sumi, Yasunori
Early detection, monitoring and remineralization repair of enamel lesions are top research priorities in the modern dentistry focusing on minimal intervention concept for caries management. We investigate the use of swept-source optical coherence tomography system (SS-OCT) without polarization-sensing at 1319 nm wavelength developed for clinical dentistry (Dental OCT System Prototype 2, Panasonic Healthcare Co., Ltd., Japan) in quantitative assessment of artificial enamel lesions and their remineralization. Bovine enamel blocks were subjected to demineralization to create subsurface lesions approximately 130 μm in depth over 2 weeks, and subjected to remineralization in solution containing bioavailable calcium and 1ppm fluoride at pH 6.5 for 2 weeks. Cross-sectional images of sound, demineralized and remineralized specimens were captured under hydrated conditions by the OCT. Finally, the specimens were cut into sections for nanoindentation to measure hardness through the lesion under 2mN load. Reflectivity had increased with demineralization. OCT images of lesions showed a boundary closely suggesting the lesion depth that gradually progressed with demineralization time. After remineralization, the boundary depth gradually decreased and nanoindentation showed over 60% average hardness recovery rate. A significant negative correlation was found between the slope power-law regression as a measure of attenuation and overall nanohardness for a range of data covering sound, demineralized and remineralized areas. In conclusion, OCT could provide clear images of early enamel lesion extent and signal attenuation could indicate its severity and recovery. Clinical data of natural lesions obtained using Dental OCT and analyzed by this approach will also be presented. Study supported by GCOE IRCMSTBD and NCGG.
NASA Astrophysics Data System (ADS)
Kamthonkiat, D.; Rodfai, C.; Saiwanrungkul, A.; Koshimura, S.; Matsuoka, M.
2011-07-01
In the aftermath of the 2004 Indian Ocean Tsunami, it has been proven that mangrove ecosystems provide protection against coastal disasters by acting as bioshields. Satellite data have been effectively used to detect, assess, and monitor the changes in mangroves during the pre- and post- tsunami periods. However, not much information regarding mangrove restoration or reforestation is available. Rather than undertaking time-consuming fieldwork, this study proposed using geoinformatic technologies such as Remote Sensing (RS), Geographic Information System (GIS), and Global Positioning System (GPS) to monitor the mangrove recovery. The analysis focused only on the tsunami-impacted mangrove areas along the western coast of the Tai Muang, Takuapa and Khuraburi Districts of Phang Nga Province, southern region of Thailand. The results consisted of 2 parts, first: the supervised classification of main land uses, namely forest, mangrove, agricultural land, built-up area, bare soil, water body, and miscellaneous covers in ASTER images, was conducted using the maximum likelihood method with higher than 75 % for overall accuracy. Once the confusion between classes was improved in post-processing, the accuracy of mangrove class was greater than 85 % for all dates. The results showed that the mangrove area in 2005 was reduced by approximately 5 % (1054.5 ha) from 2003 due to the impact of the 2004 Indian Ocean Tsunami. Although the recovery program (replacing the same species of dead mangrove trees, mainly the Rhizophora apiculata Bl and Rhizophora mucronata Poir, in situ) had started by mid-2005, the areas gradually decreased to approximately 7-8 % in 2006 and 2010 compared with the reference year of 2003. Second, the recovery trend was observed in the Normalized Difference Vegetation Index (NDVI) fluctuation curve and the supporting field survey data. The recovery patterns were summarized into 2 categories: (i) gradually recovery, and (ii) fluctuating recovery. The gradually recovery category that implied the homogeneous pattern or uniform reforestation was observed in the seriously damaged area where most of the mangrove trees were swept away during the tsunami. This pattern covered approximately 50.35 % of the total reforested area. The NDVI time series of the uniform or homogeneous reforested mangrove at the sampled plots has gradually increased after 2005. The fluctuating recovery category that implied the heterogeneous pattern or non-uniform reforestation was observed in partially damaged areas where some of the mangrove trees were swept away and broken but still some trees were remained in the area. The heterogeneous patterns covered approximately 49.65 % of the total reforested area.
Satellite assessment of increasing tree cover 1982-2016
NASA Astrophysics Data System (ADS)
Song, X. P.; Hansen, M.
2017-12-01
The Earth's vegetation has undergone dramatic changes as we enter the Anthropocene. Recent studies have quantified global forest cover dynamics and resulting biogeochemical and biophysical impacts to the climate for the post-2000 time period. However, long-term gradual changes in undisturbed forests are less well quantified. We mapped annual tree cover using satellite data and quantified tree cover change during 1982-2016. The dataset was produced by combining optical observations from multiple satellite sensors, including the Advanced Very High Resolution Radiometer, the Moderate Resolution Imaging Spectroradiometer, the Landsat Enhanced Thematic Mapper Plus and various very high spatial resolution sensors. Contrary to current understanding of forest area change, global tree cover increased by 7%. The overall net gain in tree cover is a result of net loss in the tropics overweighed by net gain in the subtropical, temperate and boreal zones. All mountain systems, regardless of climate domain, experienced increases in tree cover. Regional patterns of tree cover gain including eastern United States, eastern Europe and southern China, indicate profound influences of socioeconomic, political or land management changes in shaping long-term environmental change. Results provide the first comprehensive record of global tree cover dynamics over the past four decades and may be used to reduce uncertainties in the quantification of the global carbon cycle.
Xian, George Z.; Homer, Collin G.; Aldridge, Cameron L.
2012-01-01
This research investigated the effects of climate and land cover change on variation in sagebrush ecosystems. We combined information of multi-year sagebrush distribution derived from multitemporal remote sensing imagery and climate data to study the variation patterns of sagebrush ecosystems under different potential disturbances. We found that less than 40% of sagebrush ecosystem changes involved abrupt changes directly caused by landscape transformations and over 60% of the variations involved gradual changes directly related to climatic perturbations. The primary increases in bare ground and declines in sagebrush vegetation abundance were significantly correlated with the 1996-2006 decreasing trend in annual precipitation.
Nd Isotopic Provenance of Sedimentary Rocks Along Margins of North America: ten Years of Study
NASA Astrophysics Data System (ADS)
Patchett, J.; Ross, G. M.
2001-12-01
Ten years of effort, principally employing Nd isotopes, have resulted in substantial advances in understanding of the movements of sedimentary material around North America from Cambrian to Cretaceous time. This synthesis has depended upon work of current and former students S. Samson, J. Gleason, N. Boghossian, C. Garzione, M. Roth, B. Canale and E. Rosenberg, as well as collaborators W. Dickinson and A. Embry, among others. Nd isotopes are particularly good at documenting movements of sedimentary material on the largest (continental) scale and over extended times. What has emerged is a picture of a largely exposed North America-Greenland craton from Neoproterozoic to Ordovician time, a partial to complete burial by detritus from Caledonian-Appalachian mountains starting in the Ordovician, a gradual exhumation during Late Paleozoic and Mesozoic time, followed by a partial burial with Cordilleran detritus during Late Jurassic to Tertiary time. One current question is the nature of the Mesozoic and Tertiary sedimentary material eroded from the North American Cordillera, and its relevance for Cordilleran orogenesis. Another current question is the extent to which Caledonian-Appalachian detritus covered the craton in Devonian-Carboniferous time, and the timing and manner of its removal during Mesozoic time. At first glance, available Nd isotopic data appear to suggest that the Canada-Greenland Shield was largely covered during most of Mesozoic time, a conclusion that would have profound effects on models of dynamic topography. However, this conclusion is also very dependent on the relationship between topography and erosion, because in certain situations a geographically-restricted cover sequence could dominate over low-relief cratonic terrain as a sediment source.
The Two Sources of Solar Energetic Particles
NASA Astrophysics Data System (ADS)
Reames, Donald V.
2013-06-01
Evidence for two different physical mechanisms for acceleration of solar energetic particles (SEPs) arose 50 years ago with radio observations of type III bursts, produced by outward streaming electrons, and type II bursts from coronal and interplanetary shock waves. Since that time we have found that the former are related to "impulsive" SEP events from impulsive flares or jets. Here, resonant stochastic acceleration, related to magnetic reconnection involving open field lines, produces not only electrons but 1000-fold enhancements of 3He/4He and of ( Z>50)/O. Alternatively, in "gradual" SEP events, shock waves, driven out from the Sun by coronal mass ejections (CMEs), more democratically sample ion abundances that are even used to measure the coronal abundances of the elements. Gradual events produce by far the highest SEP intensities near Earth. Sometimes residual impulsive suprathermal ions contribute to the seed population for shock acceleration, complicating the abundance picture, but this process has now been modeled theoretically. Initially, impulsive events define a point source on the Sun, selectively filling few magnetic flux tubes, while gradual events show extensive acceleration that can fill half of the inner heliosphere, beginning when the shock reaches ˜2 solar radii. Shock acceleration occurs as ions are scattered back and forth across the shock by resonant Alfvén waves amplified by the accelerated protons themselves as they stream away. These waves also can produce a streaming-limited maximum SEP intensity and plateau region upstream of the shock. Behind the shock lies the large expanse of the "reservoir", a spatially extensive trapped volume of uniform SEP intensities with invariant energy-spectral shapes where overall intensities decrease with time as the enclosing "magnetic bottle" expands adiabatically. These reservoirs now explain the slow intensity decrease that defines gradual events and was once erroneously attributed solely to slow outward diffusion of the particles. At times the reservoir from one event can contribute its abundances and even its spectra as a seed population for acceleration by a second CME-driven shock wave. Confinement of particles to magnetic flux tubes that thread their source early in events is balanced at late times by slow velocity-dependent migration through a tangled network produced by field-line random walk that is probed by SEPs from both impulsive and gradual events and even by anomalous cosmic rays from the outer heliosphere. As a practical consequence, high-energy protons from gradual SEP events can be a significant radiation hazard to astronauts and equipment in space and to the passengers of high-altitude aircraft flying polar routes.
A Web Based Puzzle for Energy Sources
ERIC Educational Resources Information Center
Secken, Nilgun
2006-01-01
At present many countries in the world consume too much fossil fuels such as petroleum, natural gas and coal to meet their energy needs. These fossil fuels are not renewable; their sources are limited and reducing gradually. More importantly they have been becoming more expensive day by day and their damage to the environment has been increasing.…
Yin, Ke; Zhu, Rongzhen; Zhang, Bin; Jiang, Tian; Chen, Shengping; Hou, Jing
2016-09-05
Fiber based supercontinuum (SC) sources with output spectra covering the infrared atmospheric window are very useful in long-range atmospheric applications. It is proven that silica fibers can support the generation of broadband SC sources ranging from the visible to the short-wave infrared region. In this paper, we present the generation of an ultrahigh-brightness spectrally-flat 2-2.5 μm SC source in a cladding pumped thulium-doped fiber amplifier (TDFA) numerically and experimentally. The underlying physical mechanisms behind the SC generation process are investigated firstly with a numerical model which includes the fiber gain and loss, the dispersive and nonlinear effects. Simulation results show that abundant soliton pulses are generated in the TDFA, and they are shifted towards the long wavelength side very quickly with the nonlinearity of Raman soliton self-frequency shift (SSFS), and eventually the Raman SSFS process is halted due to the silica fiber's infrared loss. A spectrally-flat 2-2.5 μm SC source could be generated as the result of the spectral superposition of these abundant soliton pulses. These simulation results correspond qualitatively well to the following experimental results. Then, in the experiment, a cladding pumped large-mode-area TDFA is built for pursuing a high-power 2-2.5 μm SC source. By enhancing the pump strength, the output SC spectrum broadens to the long wavelength side gradually. At the highest pump power, the obtained SC source has a maximum average power of 203.4 W with a power conversion efficiency of 38.7%. It has a 3 dB spectral bandwidth of 545 nm ranging from 1990 to 2535 nm, indicating a power spectral density in excess of 370 mW/nm. Meanwhile, the output SC source has a good beam profile. This SC source, to the best of our knowledge, is the brightest spectrally-flat 2-2.5 μm light source ever reported. It will be highly desirable in a lot of long-range atmospheric applications, such as broad-spectrum LIDAR, free space communication and hyper-spectral imaging.
NASA Astrophysics Data System (ADS)
Velpuri, N. M.; Senay, G. B.
2017-12-01
Information on how much of direct rain water (green water) and/or non-rain water (blue water) are being productively used by the crops/vegetation is critical for efficient water resources management. In this study, we developed a simple but robust methodology to partition actual evapotranspiration (ET) into green (rainfall-based) and blue (surface water/groundwater) sources. We combined two 1 km MODIS-based actual evapotranspiration datasets, one obtained from a root zone water balance model and another from an energy balance model, to partition annual ET into green water ET (GWET) and blue water ET (BWET). Time series maps of GWET and BWET were produced for the conterminous United States (CONUS) over 2001-2015 and spatial variability and dynamics of blue and green water ET were analyzed. Our results indicate that average green and blue water sources for all land cover types in CONUS account for nearly 70% and 30% of the total ET, respectively. The ET in the eastern US arises mostly from green water, and in the western US, it is mostly from blue water sources. Analysis of the BWET in the 16 selected irrigated areas in CONUS revealed interesting results. While the magnitude of the BWET showed a gradual decline from west to east, the increase in coefficient of variation from west to east confirmed greater use of supplemental irrigation in the central and eastern US. We also established relationships between hydro-climatic regions and their blue water requirements. This study provides insights into the relative contributions and the spatiotemporal dynamics of GWET and BWET, which could lead to improved water resources management.
Zhu, Zhe; Fu, Yingchun; Woodcock, Curtis; Olofsson, Pontus; Vogelmann, James; Holden, Christopher; Wang, Min; Dai, Shu; Yu, Yang
2016-01-01
An assessment of the consistency of surface reflectance from Landsat 8 with past Landsat sensors indicates biases in the visible bands of Landsat 8, especially the blue band. Landsat 8 NDVI values were found to have a larger bias than the EVI values; therefore, EVI was used in the analysis of greenness trends for Guangzhou. In spite of massive amounts of development in Guangzhou from 2000 to 2014, greenness was found to increase, mostly as a result of gradual change. Comparison of the greening magnitudes estimated from the approach presented here and a Simple Linear Trend (SLT) method indicated large differences for certain time intervals as the SLT method does not include consideration for abrupt land cover changes. Overall, this analysis demonstrates the importance of considering land cover change when analyzing trends in greenness from satellite time series in areas where land cover change is common.
Sensitivity properties of a biosphere model based on BATS and a statistical-dynamical climate model
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, T.
A biosphere model based on the Biosphere-Atmosphere Transfer Scheme (BATS) and the Saltzman-Vernekar (SV) statistical-dynamical climate model is developed. Some equations of BATS are adopted either intact or with modifications, some are conceptually modified, and still others are replaced with equations of the SV model. The model is designed so that it can be run independently as long as the parameters related to the physiology and physiognomy of the vegetation, the atmospheric conditions, solar radiation, and soil conditions are given. With this stand-alone biosphere model, a series of sensitivity investigations, particularly the model sensitivity to fractional area of vegetation cover,more » soil surface water availability, and solar radiation for different types of vegetation, were conducted as a first step. These numerical experiments indicate that the presence of a vegetation cover greatly enhances the exchanges of momentum, water vapor, and energy between the atmosphere and the surface of the earth. An interesting result is that a dense and thick vegetation cover tends to serve as an environment conditioner or, more specifically, a thermostat and a humidistat, since the soil surface temperature, foliage temperature, and temperature and vapor pressure of air within the foliage are practically insensitive to variation of soil surface water availability and even solar radiation within a wide range. An attempt is also made to simulate the gradual deterioration of environment accompanying gradual degradation of a tropical forest to grasslands. Comparison with field data shows that this model can realistically simulate the land surface processes involving biospheric variations. 46 refs., 10 figs., 6 tabs.« less
Sensitivity properties of a biosphere model based on BATS and a statistical-dynamical climate model
NASA Technical Reports Server (NTRS)
Zhang, Taiping
1994-01-01
A biosphere model based on the Biosphere-Atmosphere Transfer Scheme (BATS) and the Saltzman-Vernekar (SV) statistical-dynamical climate model is developed. Some equations of BATS are adopted either intact or with modifications, some are conceptually modified, and still others are replaced with equations of the SV model. The model is designed so that it can be run independently as long as the parameters related to the physiology and physiognomy of the vegetation, the atmospheric conditions, solar radiation, and soil conditions are given. With this stand-alone biosphere model, a series of sensitivity investigations, particularly the model sensitivity to fractional area of vegetation cover, soil surface water availability, and solar radiation for different types of vegetation, were conducted as a first step. These numerical experiments indicate that the presence of a vegetation cover greatly enhances the exchanges of momentum, water vapor, and energy between the atmosphere and the surface of the earth. An interesting result is that a dense and thick vegetation cover tends to serve as an environment conditioner or, more specifically, a thermostat and a humidistat, since the soil surface temperature, foliage temperature, and temperature and vapor pressure of air within the foliage are practically insensitive to variation of soil surface water availability and even solar radiation within a wide range. An attempt is also made to simulate the gradual deterioration of environment accompanying gradual degradation of a tropical forest to grasslands. Comparison with field data shows that this model can realistically simulate the land surface processes involving biospheric variations.
Designing a gradual transition to a hydrogen economy in Spain
NASA Astrophysics Data System (ADS)
Brey, J. J.; Brey, R.; Carazo, A. F.; Contreras, I.; Hernández-Díaz, A. G.; Gallardo, V.
The lack of sustainability of the current Spanish energy system makes it necessary to study the adoption of alternative energy models. One of these is what is known as the hydrogen economy. In this paper, we aim to plan, for the case of Spain, an initial phase for transition to this energy model making use of the potential offered by each Spanish region. Specifically, the target pursued is to satisfy at least 15% of energy demand for transport by 2010 through renewable sources. We plan to attain this target gradually, establishing intermediate stages consisting of supplying 5 and 10% of the energy demand for transport by 2006 and 2008, respectively. The results obtained allow us to determine, for each region, the hydrogen production and consumption, the renewable energy sources used to obtain hydrogen and the transport requirements between regions.
Pb concentrations and isotopic record preserved in northwest Greenland snow.
Kang, Jung-Ho; Hwang, Heejin; Han, Changhee; Hur, Soon Do; Kim, Seong-Joong; Hong, Sungmin
2017-11-01
We present high-resolution lead (Pb) concentrations and isotopic ratios from a northwest Greenland snow pit covering a six-year period between 2003 and 2009. Pb concentrations ranged widely from 2.7 pg g -1 to 97.3 pg g -1 , with a mean concentration of 21.6 pg g -1 . These values are higher than those recorded for the pre-industrial period. Pb concentrations exhibit seasonal spikes in winter-spring layers. Crustal Pb enrichment factors (EF) suggest that the northwest Greenland snow pit is highly enriched with Pb of predominantly anthropogenic origin. The 206 Pb/ 207 Pb ratios ranged from 1.144 to 1.169 with a mean value of 1.156, which fall between less radiogenic Eurasian-type and more radiogenic Canadian-type signatures. This result suggests that several potential source areas of Pb impact on northwest Greenland. Abrupt changes in Pb concentrations and Pb isotope ratios were observed and related to seasonal shifts in source regions of aerosol transport. The 206 Pb/ 207 Pb isotope ratio increased gradually between 2003 and 2009. The similarity of the three-isotope plot ( 206 Pb/ 207 Pb versus 208 Pb/ 207 Pb) between some of our samples and Chinese urban aerosols suggests a steadily increasing contribution of Chinese Pb to northwest Greenland snow. Copyright © 2017. Published by Elsevier Ltd.
Fu, Qiang; Hou, Renjie; Li, Tianxiao; Jiang, Ruiqi; Yan, Peiru; Ma, Ziao; Zhou, Zhaoqiang
2018-01-22
In this study, the spatial variations of soil water and heat under bare land (BL), natural snow (NS), compacted snow (CS) and thick snow (TS) treatments were analyzed. The relationship curve between soil temperature and water content conforms to the exponential filtering model, by means of the functional form of the model, it was defined as soil water and heat relation function model. On this basis, soil water and heat function models of 10, 20, 40, 60, 100, and 140 cm were established. Finally, a spatial variation law of the relationship effect was described based on analysising of the differences between the predicted and measured results. During freezing period, the effects of external factors on soil were hindered by snow cover. As the snow increased, the accuracy of the function model gradually improved. During melting period, infiltration by snowmelt affected the relationship between the soil temperature and moisture. With the increasing of snow, the accuracy of the function models gradually decreased. The relationship effects of soil water and heat increased with increasing depth within the frozen zone. In contrast, below the frozen layer, the relationship of soil water and heat was weaker, and the function models were less accurate.
NASA Astrophysics Data System (ADS)
Nieuwendam, Alexandre; Ramos, Miguel; Vieira, Gonçalo
2015-04-01
In permafrost areas the seasonal snow cover is an important factor on the ground thermal regime. Snow depth and timing are important in ground insulation from the atmosphere, creating different snow patterns and resulting in spatially variable ground temperatures. The aim of this work is to characterize the interactions between ground thermal regimes and snow cover and the influence on permafrost spatial distribution. The study area is the ice-free terrains of northwestern Hurd Peninsula in the vicinity of the Spanish Antarctic Station "Juan Carlos I" and Bulgarian Antarctic Station "St. Kliment Ohridski". Air and ground temperatures and snow thickness data where analysed from 4 sites along an altitudinal transect in Hurd Peninsula from 2007 to 2012: Nuevo Incinerador (25 m asl), Collado Ramos (110 m), Ohridski (140 m) and Reina Sofia Peak (275 m). The data covers 6 cold seasons showing different conditions: i) very cold with thin snow cover; ii) cold with a gradual increase of snow cover; iii) warm with thick snow cover. The data shows three types of periods regarding the ground surface thermal regime and the thickness of snow cover: a) thin snow cover and short-term fluctuation of ground temperatures; b) thick snow cover and stable ground temperatures; c) very thick snow cover and ground temperatures nearly constant at 0°C. a) Thin snow cover periods: Collado Ramos and Ohridski sites show frequent temperature variations, alternating between short-term fluctuations and stable ground temperatures. Nuevo Incinerador displays during most of the winter stable ground temperatures; b) Cold winters with a gradual increase of the snow cover: Nuevo Incinerador, Collado Ramos and Ohridski sites show similar behavior, with a long period of stable ground temperatures; c) Thick snow cover periods: Collado Ramos and Ohridski show long periods of stable ground, while Nuevo Incinerador shows temperatures close to 0°C since the beginning of the winter, due to early snow cover, which prevents cooling. Reina Sofia shows a very different behavior from the other sites, with a frequent stabilization of ground temperatures during all the winters, and last until late-fall. This situation could be related to the structure, and physical and thermal properties of snow cover. The analysis of the Freezing Degree Days (FDDs) and freezing n-factor reveals significant interannual variations. Ohridski shows the highest FDDs values followed by Reina Sofia. Nuevo Incinerador showed the lowest FDDs values. The freezing n-factor shows highest values at Ohridski, followed by Collado Ramos and Reina Sofia with very similar values. Nuevo Incinerador shows the lowest n-factor values. Snow cover doesn't insulate the ground from freezing, but depending on its thickness, density and the amount of heat in the ground, it decreases ground temperatures amplitudes and increases delays relative to air temperature changes. Even where snow cover remains several centimeters thick for several months, slow decrease of bottom temperature is possible, reaching a minimum value at the end of the winter. The results demonstrate that Reina Sofia and Ohridski sites, because of the seasonal behavior, FDDs and freezing n-factor, demonstrate higher winter ground cooling. This research was funded by PERMANTAR-3 (PTDC/AAG-GLO/3908/2012) project (Fundação para a Ciência e a Tecnologia of Portugal)
Slow recovery in desert perennial vegetation following prolonged human disturbance
Guo, Q.
2004-01-01
The study shows an exceptionally long-term recovery of perennial vegetation from prolonged heavy grazing and other human impacts. Since protection in 1906, overall species richness and habitat heterogeneity at the study site continued to increase until the 1960s when diversity, density and cover stabilized. During the same period, overall plant density and cover also increased. Species turnover increased gradually with time but no significant relation between any of the three community variables and precipitation or Palmer Drought Severity Index (PDSI) was detected. The increases in plant species richness, density, and cover of the perennial vegetation were mostly due to the increase of herbaceous species, especially palatable species. The lack of clear relationship between environment (e.g., precipitation) and community variables suggests that site history and plant life history must be taken into account in examining the nature of vegetation recovery process after disturbances.
Axially Tapered And Bilayer Microchannels For Evaporative Cooling Devices
Nilson, Robert; Griffiths, Stewart
2005-10-04
The invention consists of an evaporative cooling device comprising one or more microchannels whose cross section is axially reduced to control the maximum capillary pressure differential between liquid and vapor phases. In one embodiment, the evaporation channels have a rectangular cross section that is reduced in width along a flow path. In another embodiment, channels of fixed width are patterned with an array of microfabricated post-like features such that the feature size and spacing are gradually reduced along the flow path. Other embodiments incorporate bilayer channels consisting of an upper cover plate having a pattern of slots or holes of axially decreasing size and a lower fluid flow layer having channel widths substantially greater than the characteristic microscale dimensions of the patterned cover plate. The small dimensions of the cover plate holes afford large capillary pressure differentials while the larger dimensions of the lower region reduce viscous flow resistance.
Response of herbivore functional groups to sequential perturbations in Moorea, French Polynesia
NASA Astrophysics Data System (ADS)
Han, Xueying; Adam, Thomas C.; Schmitt, Russell J.; Brooks, Andrew J.; Holbrook, Sally J.
2016-09-01
The reefs surrounding the island of Moorea, French Polynesia, experienced two large pulse perturbations between 2008 and 2010, an outbreak of the crown-of-thorns seastar ( Acanthaster planci) followed by a cyclone, that resulted in the reduction in live coral cover on the fore reef from ~40 to <5 %. Live coral cover in back reef and fringing reef habitats initially remained relatively stable, but began a gradual decline around 2010. We assessed the changes in the functional composition of the herbivorous fish community following the pulse perturbations and during the time of gradual coral decline on the back reef and fringing reef. Forty-nine species of herbivorous fishes quantified in yearly surveys between 2006 and 2014 were assigned to six functional groups: browser, detritivore, excavator, farmer, grazer/detritivore, and scraper. Non-metric multidimensional scaling analyses revealed that despite unique functional assemblages initially existing among the fringing reef, back reef, and fore reef habitats, the herbivorous fish communities in all three habitats responded in a qualitatively similar fashion to coral decline by moving toward functional communities characterized by an increased representation of excavators and scrapers. Island-wide scraper biomass increased by ~sevenfold in the post-disturbance time period, while excavator biomass increased by nearly threefold. The biomass of detritivores and grazers/detritivores also increased over the same time period, but to a much lesser degree, while the biomass of browsers and farmers remained essentially unchanged. Macroalgae remained a relatively minor space holder (<10 % cover) in lagoon habitats and on the fore reef through 2014, enabling recruitment of juvenile coral and initiating coral recovery on the fore reef. Results suggest that a functional community with a substantial biomass of herbivores and the capacity for the biomass of scrapers and excavators to increase rapidly in response to landscape-scale declines in coral cover may enhance resilience by preventing the widespread establishment of macroalgae.
Thresholds for boreal biome transitions.
Scheffer, Marten; Hirota, Marina; Holmgren, Milena; Van Nes, Egbert H; Chapin, F Stuart
2012-12-26
Although the boreal region is warming twice as fast as the global average, the way in which the vast boreal forests and tundras may respond is poorly understood. Using satellite data, we reveal marked alternative modes in the frequency distributions of boreal tree cover. At the northern end and at the dry continental southern extremes, treeless tundra and steppe, respectively, are the only possible states. However, over a broad intermediate temperature range, these treeless states coexist with boreal forest (∼75% tree cover) and with two more open woodland states (∼20% and ∼45% tree cover). Intermediate tree covers (e.g., ∼10%, ∼30%, and ∼60% tree cover) between these distinct states are relatively rare, suggesting that they may represent unstable states where the system dwells only transiently. Mechanisms for such instabilities remain to be unraveled, but our results have important implications for the anticipated response of these ecosystems to climatic change. The data reveal that boreal forest shows no gradual decline in tree cover toward its limits. Instead, our analysis suggests that it becomes less resilient in the sense that it may more easily shift into a sparse woodland or treeless state. Similarly, the relative scarcity of the intermediate ∼10% tree cover suggests that tundra may shift relatively abruptly to a more abundant tree cover. If our inferences are correct, climate change may invoke massive nonlinear shifts in boreal biomes.
NASA Technical Reports Server (NTRS)
Schlegel, E.; Norris, Jay P. (Technical Monitor)
2002-01-01
This project was awarded funding from the CGRO program to support ROSAT and ground-based observations of unidentified sources from data obtained by the EGRET instrument on the Compton Gamma-Ray Observatory. The critical items in the project are the individual ROSAT observations that are used to cover the 99% error circle of the unidentified EGRET source. Each error circle is a degree or larger in diameter. Each ROSAT field is about 30 deg in diameter. Hence, a number (>4) of ROSAT pointings must be obtained for each EGRET source to cover the field. The scheduling of ROSAT observations is carried out to maximize the efficiency of the total schedule. As a result, each pointing is broken into one or more sub-pointings of various exposure times. This project was awarded ROSAT observing time for four unidentified EGRET sources, summarized in the table. The column headings are defined as follows: 'Coverings' = number of observations to cover the error circle; 'SubPtg' = total number of sub-pointings to observe all of the coverings; 'Rec'd' = number of individual sub-pointings received to date; 'CompFlds' = number of individual coverings for which the requested complete exposure has been received. Processing of the data can not occur until a complete exposure has been accumulated for each covering.
Recovery audits are back: tactics for tough times.
Cascardo, Debra
2010-01-01
The Recovery Audit Contractor (RAC) Program was implemented in stages in 2009. Section 302 of the Tax Relief and Health Care Act of 2006 required full implementation no later than January 1, 2010. The first phase began in March 2009 and covered various states; the second phase began in August 2009. The Centers for Medicare & Medicaid Services is gradually implementing the RAC permanent program, and it will ultimately affect every provider in every state.
Stress Corrosion of Ceramic Materials.
1986-08-01
rupture directly, or are hydrolyzed by the water in the environment. This type of reaction is known to be important to the corrosion of glass in basic...covered .ith silanol groups so that the surface is virtually uncharged. As the pH is increased, the surface gradually hydrolyzes forming silanolate...is plotted assuming a decay distance of 0.3 nm. The data on lecithin is obtained by a non-fracture technique in which the layer spacing is determined
NASA Astrophysics Data System (ADS)
Wang, Weiming; Wang, Zhixuan; Chen, Xuan; Long, Fei; Lu, Shuangfang; Liu, Guohong; Tian, Weichao; Su, Yue
In this paper, in a case study of Santanghu Basin in China, the morphological characteristics and size distribution of nanoscale pores in the volcanic rocks of the Haerjiawu Formation were investigated using the results of low temperature nitrogen adsorption experiments. This research showed that within the target layer, a large number of nanoscale, eroded pores showed an “ink bottle” morphology with narrow pore mouths and wide bodies. The fractal dimension of pores increases gradually with increasing depth. Moreover, as fractal dimension increases, BET-specific surface area gradually increases, average pore diameter decreases and total pore volume gradually increases. The deeper burial of the Haerjiawu volcanic rocks in the Santanghu Basin leads to more intense erosion by organic acids derived from the basin’s source rocks. Furthermore, the internal surface roughness of these corrosion pores results in poor connectivity. As stated above, the corrosion process is directly related to the organic acids generated by the source rock of the interbedded volcanic rocks. The deeper the reservoir, the more the organic acids being released from the source rock. However, due to the fact that the Haerjiawu volcanic rocks are tight reservoirs and have complicated pore-throat systems, while organic acids dissolve unstable minerals such as feldspars which improve the effective reservoir space; the dissolution of feldspars results in the formation of new minerals, which cannot be expelled from the tight reservoirs. They are instead precipitated in the fine pore throats, thereby reducing pore connectivity, while enhancing reservoir micro-preservation conditions.
Clark, Christopher James
2014-01-01
Models of character evolution often assume a single mode of evolutionary change, such as continuous, or discrete. Here I provide an example in which a character exhibits both types of change. Hummingbirds in the genus Selasphorus produce sound with fluttering tail-feathers during courtship. The ancestral character state within Selasphorus is production of sound with an inner tail-feather, R2, in which the sound usually evolves gradually. Calliope and Allen's Hummingbirds have evolved autapomorphic acoustic mechanisms that involve feather-feather interactions. I develop a source-filter model of these interactions. The ‘source’ comprises feather(s) that are both necessary and sufficient for sound production, and are aerodynamically coupled to neighboring feathers, which act as filters. Filters are unnecessary or insufficient for sound production, but may evolve to become sources. Allen's Hummingbird has evolved to produce sound with two sources, one with feather R3, another frequency-modulated sound with R4, and their interaction frequencies. Allen's R2 retains the ancestral character state, a ∼1 kHz “ghost” fundamental frequency masked by R3, which is revealed when R3 is experimentally removed. In the ancestor to Allen's Hummingbird, the dominant frequency has ‘hopped’ to the second harmonic without passing through intermediate frequencies. This demonstrates that although the fundamental frequency of a communication sound may usually evolve gradually, occasional jumps from one character state to another can occur in a discrete fashion. Accordingly, mapping acoustic characters on a phylogeny may produce misleading results if the physical mechanism of production is not known. PMID:24722049
Characteristics of phonation onset in a two-layer vocal fold model.
Zhang, Zhaoyan
2009-02-01
Characteristics of phonation onset were investigated in a two-layer body-cover continuum model of the vocal folds as a function of the biomechanical and geometric properties of the vocal folds. The analysis showed that an increase in either the body or cover stiffness generally increased the phonation threshold pressure and phonation onset frequency, although the effectiveness of varying body or cover stiffness as a pitch control mechanism varied depending on the body-cover stiffness ratio. Increasing body-cover stiffness ratio reduced the vibration amplitude of the body layer, and the vocal fold motion was gradually restricted to the medial surface, resulting in more effective flow modulation and higher sound production efficiency. The fluid-structure interaction induced synchronization of more than one group of eigenmodes so that two or more eigenmodes may be simultaneously destabilized toward phonation onset. At certain conditions, a slight change in vocal fold stiffness or geometry may cause phonation onset to occur as eigenmode synchronization due to a different pair of eigenmodes, leading to sudden changes in phonation onset frequency, vocal fold vibration pattern, and sound production efficiency. Although observed in a linear stability analysis, a similar mechanism may also play a role in register changes at finite-amplitude oscillations.
Identifying optimal remotely-sensed variables for ecosystem monitoring in Colorado Plateau drylands
Poitras, Travis; Villarreal, Miguel; Waller, Eric K.; Nauman, Travis; Miller, Mark E.; Duniway, Michael C.
2018-01-01
Water-limited ecosystems often recover slowly following anthropogenic or natural disturbance. Multitemporal remote sensing can be used to monitor ecosystem recovery after disturbance; however, dryland vegetation cover can be challenging to accurately measure due to sparse cover and spectral confusion between soils and non-photosynthetic vegetation. With the goal of optimizing a monitoring approach for identifying both abrupt and gradual vegetation changes, we evaluated the ability of Landsat-derived spectral variables to characterize surface variability of vegetation cover and bare ground across a range of vegetation community types. Using three year composites of Landsat data, we modeled relationships between spectral information and field data collected at monitoring sites near Canyonlands National Park, UT. We also developed multiple regression models to assess improvement over single variables. We found that for all vegetation types, percent cover bare ground could be accurately modeled with single indices that included a combination of red and shortwave infrared bands, while near infrared-based vegetation indices like NDVI worked best for quantifying tree cover and total live vegetation cover in woodlands. We applied four models to characterize the spatial distribution of putative grassland ecological states across our study area, illustrating how this approach can be implemented to guide dryland ecosystem management.
40 CFR 63.7282 - What parts of my plant does this subpart cover?
Code of Federal Regulations, 2011 CFR
2011-07-01
... CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Coke Ovens: Pushing... cover? (a) This subpart applies to each new or existing affected source at your coke plant. The affected source is each coke oven battery. (b) This subpart covers emissions from pushing, soaking, quenching, and...
40 CFR 63.7282 - What parts of my plant does this subpart cover?
Code of Federal Regulations, 2014 CFR
2014-07-01
... CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Coke Ovens: Pushing... cover? (a) This subpart applies to each new or existing affected source at your coke plant. The affected source is each coke oven battery. (b) This subpart covers emissions from pushing, soaking, quenching, and...
40 CFR 63.7282 - What parts of my plant does this subpart cover?
Code of Federal Regulations, 2010 CFR
2010-07-01
... CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Coke Ovens: Pushing... cover? (a) This subpart applies to each new or existing affected source at your coke plant. The affected source is each coke oven battery. (b) This subpart covers emissions from pushing, soaking, quenching, and...
40 CFR 63.7282 - What parts of my plant does this subpart cover?
Code of Federal Regulations, 2013 CFR
2013-07-01
... CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Coke Ovens: Pushing... cover? (a) This subpart applies to each new or existing affected source at your coke plant. The affected source is each coke oven battery. (b) This subpart covers emissions from pushing, soaking, quenching, and...
40 CFR 63.7282 - What parts of my plant does this subpart cover?
Code of Federal Regulations, 2012 CFR
2012-07-01
... CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Coke Ovens: Pushing... cover? (a) This subpart applies to each new or existing affected source at your coke plant. The affected source is each coke oven battery. (b) This subpart covers emissions from pushing, soaking, quenching, and...
Kuwait Oil Fields as seen from STS-58
NASA Technical Reports Server (NTRS)
1993-01-01
A clear view of the northern Kuwait coast shows the southern part of Kuwait City, and the major oil fields to the south. Oil laden sands, where wells were set ablaze during the Gulf War in 1991, are visible south of Kuwait City as a dark, elongated patch surrounded by light-colored sand. Oil-stained sandbetween well sites (dots) and criss-crossing roads is gradually being covered by clean sand carried by strong, seasonal northwest winds.
NASA Astrophysics Data System (ADS)
Han, Xianming; Zuo, Depeng; Xu, Zongxue; Cai, Siyang; Gao, Xiaoxi
2018-06-01
The Yarlung Zangbo River Basin is located in the southwest border of China, which is of great significance to the socioeconomic development and ecological environment of Southwest China. Normalized Difference Vegetation Index (NDVI) is an important index for investigating the change of vegetation cover, which is widely used as the representation value of vegetation cover. In this study, the NDVI is adopted to explore the vegetation condition in the Yarlung Zangbo River Basin during the recent 17 years, and the relationship between NDVI and meteorological variables has also been discussed. The results show that the annual maximum value of NDVI usually appears from July to September, in which August occupies a large proportion. The minimum value of NDVI appears from January to March, in which February takes up most of the percentage. The higher values of NDVI are generally located in the lower elevation area. When the altitude is higher than 3250 m, NDVI began to decline gradually, and the NDVI became gradual stabilization as the elevation is up to 6000 m. The correlation coefficient between NDVI and precipitation in the Yarlung Zangbo River Basin is greater than that with temperature. The Hurst index of the whole basin is 0.51, indicating that the NDVI of the Yarlung Zangbo River Basin shows a weak sustainability.
Seasonally-Dynamic SPARROW Modeling of Nitrogen Flux Using Earth Observation Data
NASA Astrophysics Data System (ADS)
Smith, R. A.; Schwarz, G. E.; Brakebill, J. W.; Hoos, A. B.; Moore, R. B.; Shih, J.; Nolin, A. W.; Macauley, M.; Alexander, R. B.
2013-12-01
SPARROW models are widely used to identify and quantify the sources of contaminants in watersheds and to predict their flux and concentration at specified locations downstream. Conventional SPARROW models describe the average relationship between sources and stream conditions based on long-term water quality monitoring data and spatially-referenced explanatory information. But many watershed management issues stem from intra- and inter-annual changes in contaminant sources, hydrologic forcing, or other environmental conditions which cause a temporary imbalance between inputs and stream water quality. Dynamic behavior of the system relating to changes in watershed storage and processing then becomes important. In this study, we describe dynamically calibrated SPARROW models of total nitrogen flux in three sub-regional watersheds: the Potomac River Basin, Long Island Sound drainage, and coastal South Carolina drainage. The models are based on seasonal water quality and watershed input data for a total 170 monitoring stations for the period 2001 to 2008. Frequently-reported, spatially-detailed input data on the phenology of agricultural production, terrestrial vegetation growth, and snow melt are often challenging requirements of seasonal modeling of reactive nitrogen. In this NASA-funded research, we use Enhanced Vegetation Index (EVI), gross primary production and snow/ice cover data from MODIS to parameterize seasonal uptake and release of nitrogen from vegetation and snowpack. The spatial reference frames of the models are 1:100,000-scale stream networks, and the computational time steps are 0.25-year seasons. Precipitation and temperature data are from PRISM. The model formulation accounts for storage of nitrogen from nonpoint sources including fertilized cropland, pasture, urban land, and atmospheric deposition. Model calibration is by non-linear regression. Once calibrated, model source terms based on previous season export allow for recursive dynamic simulation of stream flux: gradual increases or decreases in export occur as source supply rates and hydrologic forcing change. Based on an assumption that removal of nitrogen from watershed storage to stream channels and to 'permanent' sinks (e.g. the atmosphere and deep groundwater) occur as parallel first-order processes, the models can be used to estimate the approximate residence times of nonpoint source nitrogen in the watersheds.
Von Benda-Beckmann, Alexander M; Wensveen, Paul J; Kvadsheim, Petter H; Lam, Frans-Peter A; Miller, Patrick J O; Tyack, Peter L; Ainslie, Michael A
2014-02-01
Ramp-up or soft-start procedures (i.e., gradual increase in the source level) are used to mitigate the effect of sonar sound on marine mammals, although no one to date has tested whether ramp-up procedures are effective at reducing the effect of sound on marine mammals. We investigated the effectiveness of ramp-up procedures in reducing the area within which changes in hearing thresholds can occur. We modeled the level of sound killer whales (Orcinus orca) were exposed to from a generic sonar operation preceded by different ramp-up schemes. In our model, ramp-up procedures reduced the risk of killer whales receiving sounds of sufficient intensity to affect their hearing. The effectiveness of the ramp-up procedure depended strongly on the assumed response threshold and differed with ramp-up duration, although extending the duration of the ramp up beyond 5 min did not add much to its predicted mitigating effect. The main factors that limited effectiveness of ramp up in a typical antisubmarine warfare scenario were high source level, rapid moving sonar source, and long silences between consecutive sonar transmissions. Our exposure modeling approach can be used to evaluate and optimize mitigation procedures. © 2013 Society for Conservation Biology.
Effects of Cover Crops on Pratylenchus penetrans and the Nematode Community in Carrot Production
Grabau, Zane J.; Zar Maung, Zin Thu; Noyes, D. Corey; Baas, Dean G.; Werling, Benjamin P.; Brainard, Daniel C.; Melakeberhan, Haddish
2017-01-01
Cover cropping is a common practice in U.S. Midwest carrot production for soil conservation, and may affect soil ecology and plant-parasitic nematodes—to which carrots are very susceptible. This study assessed the impact of cover crops—oats (Avena sativa), radish (Raphanus sativus) cv. Defender, rape (Brassica napus) cv. Dwarf Essex, and a mixture of oats and radish—on plant-parasitic nematodes and soil ecology based on the nematode community in Michigan carrot production systems. Research was conducted at two field sites where cover crops were grown in Fall 2014 preceding Summer 2015 carrot production. At Site 1, root-lesion (Pratylenchus penetrans) and stunt (Tylenchorhynchus sp.) nematodes were present at low population densities (less than 25 nematodes/100 cm3 soil), but were not significantly affected (P > 0.05) by cover crops. At Site 2, P. penetrans population densities were increased (P ≤ 0.05) by ‘Defender’ radish compared to other cover crops or fallow control during cover crop growth and midseason carrot production. At both sites, there were few short-term impacts of cover cropping on soil ecology based on the nematode community. At Site 1, only at carrot harvest, radish-oats mixture and ‘Dwarf Essex’ rape alone enriched the soil food web based on the enrichment index (P ≤ 0.05) while rape and radish increased structure index values. At Site 2, bacterivore abundance was increased by oats or radish cover crops compared to control, but only during carrot production. In general, cover crops did not affect the nematode community until nearly a year after cover crop growth suggesting that changes in the soil community following cover cropping may be gradual. PMID:28512383
Future landfill emissions and the effect of final cover installation--a case study.
Laner, David; Fellner, Johann; Brunner, Paul H
2011-07-01
Municipal solid waste (MSW) landfills are potential long-term sources of emissions. Hence, they need to be managed after closure until they do not pose a threat to humans or the environment. The case study on the Breitenau MSW landfill was performed to evaluate future emission levels for this site and to illustrate the effect of final cover installation with respect to long-term environmental risks. The methodology was based on a comprehensive assessment of the state of the landfill and included analysis of monitoring data, investigations of landfilled waste, and an evaluation of containment systems. A model to estimate future emission levels was established and site-specific predictions of leachate emissions were presented based on scenario analysis. The results are used to evaluate the future pollution potential of the landfill and to compare different aftercare concepts in view of long-term emissions. As some leachable substances became available for water flow during cover construction due to a change in the water flow pattern of the waste, a substantial increase in leachate concentrations could be observed at the site (e.g. concentrations of chloride increased from 200 to 800 mg/l and of ammonia-nitrogen from 140 to about 500 mg/l). A period of intensive flushing before the final cover installation could have reduced the amount of leachable substances within the landfill body and rapidly decreased the leachate concentrations to 11 mg Cl/l and 79 mg NH(4)-N/l within 50 years. Contrarily, the minimization of water infiltration is associated with leachate concentrations in a high range for centuries (above 400 mg Cl/l and 200 mg NH(4)-N/l) with low concomitant annual emission loads (below 12 kg/year of Cl or 9 kg/year of NH(4)-N, respectively). However, an expected gradual decrease of barrier efficiency over time would be associated with higher emission loads of 50 kg of chloride and 30 kg of ammonia-nitrogen at the maximum, but a faster decrease of leachate concentration levels. Copyright © 2011 Elsevier Ltd. All rights reserved.
APTI Course 450, Source Sampling for Particulate Pollutants. Instructor's Guide.
ERIC Educational Resources Information Center
Aldina, G. J.; And Others
This manual covers a four and one half day laboratory course in source sampling for particulates. The course presents principles and techniques necessary for performing isokinetic source sampling procedures. Lectures cover formulas dealing with basic fluid mechanics appropriate to the techniques employed. Laboratory exercises are intended to…
NASA Technical Reports Server (NTRS)
Spruce, Joseph P.; Smoot, James; Ellis, Jean; Swann, Roberta
2011-01-01
This presentation will discuss the development and use of Landsat-based impervious cover products in conjunction with land use land cover change products to assess multi-decadal urbanization across the Mobile Bay region at regional and watershed scales. This nationally important coastal region has undergone a variety of ephemeral and permanent land use land cover change since the mid-1970s, including gradual but consequential increases in urban surface cover. This urban sprawl corresponds with increased regional percent impervious cover. The region s coastal zone managers are concerned about the increasing percent impervious cover, since it can negatively influence water quality and is an important consideration for coastal conservation and restoration work. In response, we processed multi-temporal Landsat data to compute maps of percent impervious cover for multiple dates from 1974 through 2008, roughly at 5-year intervals. Each year of product was classified using one single date of leaf-on and leaf-off Landsat data in conjunction with Cubist software. We are assessing Landsat impervious cover product accuracy through comparisons to available reference data, including available NLCD impervious cover products from the USGS, raw Landsat data, plus higher spatial resolution aerial and satellite data. In particular, we are quantitatively comparing the 2008 Landsat impervious cover products to those from QuickBird 2.4-meter multispectral data. Initial visual comparisons with the QuickBird impervious cover product suggest that the 2008 Landsat product tends to underestimate impervious cover for high density urban areas and to overestimate impervious cover in established residential subdivisions mixed with forested cover. Landsat TM and ETM data appears to produce more accurate impervious cover products compared to those using lower resolution Landsat MSS data. Although imperfect, these Landsat impervious cover products have helped the Mobile Bay National Estuary Program visualize basic urbanization trends for multiple HUC-12 watersheds of concern to them and their constituents
Topographic Maps: Rediscovering an Accessible Data Source for Land Cover Change Research
ERIC Educational Resources Information Center
McChesney, Ron; McSweeney, Kendra
2005-01-01
Given some limitations of satellite imagery for the study of land cover change, we draw attention here to a robust and often overlooked data source for use in student research: USGS topographic maps. Topographic maps offer an inexpensive, rapid, and accessible means for students to analyze land cover change over large areas. We demonstrate our…
Vogelmann, James; Gallant, Alisa L.; Shi, Hua; Zhu, Zhe
2016-01-01
There are many types of changes occurring over the Earth's landscapes that can be detected and monitored using Landsat data. Here we focus on monitoring “within-state,” gradual changes in vegetation in contrast with traditional monitoring of “abrupt” land-cover conversions. Gradual changes result from a variety of processes, such as vegetation growth and succession, damage from insects and disease, responses to shifts in climate, and other factors. Despite the prevalence of gradual changes across the landscape, they are largely ignored by the remote sensing community. Gradual changes are best characterized and monitored using time-series analysis, and with the successful launch of Landsat 8 we now have appreciable data continuity that extends the Landsat legacy across the previous 43 years. In this study, we conducted three related analyses: (1) comparison of spectral values acquired by Landsats 7 and 8, separated by eight days, to ensure compatibility for time-series evaluation; (2) tracking of multitemporal signatures for different change processes across Landsat 5, 7, and 8 sensors using anniversary-date imagery; and (3) tracking the same type of processes using all available acquisitions. In this investigation, we found that data representing natural vegetation from Landsats 5, 7, and 8 were comparable and did not indicate a need for major modification prior to use for long-term monitoring. Analyses using anniversary-date imagery can be very effective for assessing long term patterns and trends occurring across the landscape, and are especially good for providing insights regarding trends related to long-term and continuous trends of growth or decline. We found that use of all available data provided a much more comprehensive level of understanding of the trends occurring, providing information about rate, duration, and intra- and inter-annual variability that could not be readily gleaned from the anniversary date analyses. We observed that using all available clear Landsat 5–8 observations with the new Continuous Change Detection and Classification (CCDC) algorithm was very effective for illuminating vegetation trends. There are a number of potential challenges for assessing gradual changes, including atmospheric impacts, algorithm development and visualization of the changes. One of the biggest challenges for studying gradual change will be the lack of appropriate data for validating results and products.
NASA Astrophysics Data System (ADS)
Kędzior, Artur; Popa, Mihai E.
2013-06-01
Kędzior, A. and Popa, E.M. 2013. Sedimentology of the Early Jurassic terrestrial Steierdorf Formation in Anina, Colonia Cehă Quarry, South Carpathians, Romania. Acta Geologica Polonica, 63 (2), 175-199. Warszawa. The continental, coal bearing Steierdorf Formation, Hettangian - Sinemurian in age, is included in the Mesozoic cover of the Reşiţa Basin, Getic Nappe, South Carpathians, Romania. The Steierdorf Formation can be studied in Anina, a coal mining center and an exceptional locality for Early Jurassic flora and fauna, occurring in the middle of the Reşiţa Basin. This paper presents the results of sedimentological, stratigraphical and paleobotanical researches undertaken in Colonia Cehă open cast mine in Anina, where the Steierdorf Formation outcrops widely. Several sedimentary facies associations have been described, these associations permitting the reconstruction of various depositional systems such as alluvial fans, braided and meandering river systems, as well as lacustrine and coal generating marsh systems of the Steierdorf Formation. The sedimentary associations recorded within the Steierdorf Formation show a gradual fining upward trend, pointing to a rising marine water table and a decreasing relief within the source area.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hu, Huidong; Liu, Ying D.; Wang, Rui
We analyze multi-spacecraft observations associated with the 2012 July 12 coronal mass ejection (CME), covering the source region on the Sun from the Solar Dynamics Observatory , stereoscopic imaging observations from the Solar Terrestrial Relations Observatory ( STEREO ), magnetic field characteristics from Mercury Surface, Space Environment, Geochemistry, and Ranging ( MESSENGER ), and type II radio burst and in situ measurements from Wind . A triangulation method based on STEREO stereoscopic observations is employed to determine the kinematics of the CME, and the outcome is compared with the results derived from the type II radio burst using a solarmore » wind electron density model. A Grad–Shafranov technique is applied to Wind in situ data to reconstruct the flux-rope structure and compare it with the observations of the solar source region, which helps in understanding the geo-effectiveness associated with the CME structure. Our conclusions are as follows: (1) the CME undergoes an impulsive acceleration, a rapid deceleration before reaching MESSENGER , and then a gradual deceleration out to 1 au, which should be considered in CME kinematics models; (2) the type II radio burst was probably produced from a high-density interaction region between the CME-driven shock and a nearby streamer or from the shock flank with lower heights, which implies uncertainties in the determination of CME kinematics using solely type II radio bursts; (3) the flux-rope orientation and chirality deduced from in situ reconstructions at Wind agree with those obtained from solar source observations; (4) the prolonged southward magnetic field near the Earth is mainly from the axial component of the largely southward inclined flux rope, which indicates the importance of predicting both the flux-rope orientation and magnetic field components in geomagnetic activity forecasting.« less
Phenotypic Plasticity of Cuticular Hydrocarbon Profiles in Insects.
Otte, Tobias; Hilker, Monika; Geiselhardt, Sven
2018-03-01
The insect integument is covered by cuticular hydrocarbons (CHCs) which provide protection against environmental stresses, but are also used for communication. Here we review current knowledge on environmental and insect-internal factors which shape phenotypic plasticity of solitary living insects, especially herbivorous ones. We address the dynamics of changes which may occur within minutes, but may also last weeks, depending on the species and conditions. Two different modes of changes are suggested, i.e. stepwise and gradual. A switch between two distinct environments (e.g. host plant switch by phytophagous insects) results in stepwise formation of two distinct adaptive phenotypes, while a gradual environmental change (e.g. temperature gradients) induces a gradual change of numerous adaptive CHC phenotypes. We further discuss the ecological and evolutionary consequences of phenotypic plasticity of insect CHC profiles by addressing the question at which conditions is CHC phenotypic plasticity beneficial. The high plasticity of CHC profiles might be a trade-off for insects using CHCs for communication. We discuss how insects cope with the challenge to produce and "understand" a highly plastic, environmentally dependent CHC pattern that conveys reliable and comprehensible information. Finally, we outline how phenotypic plasticity of CHC profiles may promote speciation in insects that rely on CHCs for mate recognition.
The impact of state road fund debt limits : an empirical analysis.
DOT National Transportation Integrated Search
2005-07-01
States have been gradually increasing their reliance on debt financing to meet their transportation funding needs. Increased reliance on debt financing has been driven by the slow growth of highway and Road Fund revenue sources, resistance to tax exp...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ko, Yuan-Kuen; Wang, Yi-Ming; Tylka, Allan J.
Gradual solar energetic particle (SEP) events are those in which ions are accelerated to their observed energies by interactions with a shock driven by a fast coronal mass ejection (CME). Previous studies have shown that much of the observed event-to-event variability can be understood in terms of shock speed and evolution in the shock-normal angle. However, an equally important factor, particularly for the elemental composition, is the origin of the suprathermal seed particles upon which the shock acts. To tackle this issue, we (1) use observed solar-wind speed, magnetograms, and the potential-field source-surface model to map the Sun-L1 interplanetary magneticmore » field (IMF) line back to its source region on the Sun at the time of the SEP observations and (2) then look for a correlation between SEP composition (as measured by Wind and Advanced Composition Explorer at ∼2-30 MeV nucleon{sup –1}) and characteristics of the identified IMF source regions. The study is based on 24 SEP events, identified as a statistically significant increase in ∼20 MeV protons and occurring in 1998 and 2003-2006, when the rate of newly emergent solar magnetic flux and CMEs was lower than in solar-maximum years, and the field-line tracing is therefore more likely to be successful. We find that the gradual SEP Fe/O is correlated with the field strength at the IMF source, with the largest enhancements occurring when the footpoint field is strong due to the nearby presence of an active region (AR). In these cases, other elemental ratios show a strong charge-to-mass (q/M) ordering (at least on average), similar to that found in impulsive events. Such results lead us to suggest that magnetic reconnection in footpoint regions near ARs bias the heavy-ion composition of suprathermal seed ions by processes qualitatively similar to those that produce larger heavy-ion enhancements in impulsive SEP events. To address potential technical concerns about our analysis, we also discuss efforts to exclude impulsive SEP events from our event sample.« less
Mariner 9 Solar Array Design, Manufacture, and Performance
NASA Technical Reports Server (NTRS)
Sequeira, E. A.
1973-01-01
The mission of Mariner 9, the first spacecraft to orbit another planet, was to make scientific observations of the surface of Mars. Throughout this unique mission, the Mariner 9 solar array successfully supported the power requirements of the spacecraft without experiencing anomalies. Basically, the design of the solar array was similar to those of Mariners 6 and 7; however, Mariner 9 had the additional flight operational requirement to perform in a Mars orbit environment mode. The array special tests provided information on the current-voltage characteristics and array space degradation. Tests indicated that total solar array current degradation was 3.5 percent, which could probably be attributed to the gradual degradation of the cover glass and/or the RTV 602 adhesive employed to cement the cover glass to the solar cell.
de Jong, Bouke; Siewers, Verena; Nielsen, Jens
2012-08-01
Transportation fuels will gradually shift from oil based fuels towards alternative fuel resources like biofuels. Current bioethanol and biodiesel can, however, not cover the increasing demand for biofuels and there is therefore a need for advanced biofuels with superior fuel properties. Novel cell factories will provide a production platform for advanced biofuels. However, deep cellular understanding is required for improvement of current biofuel cell factories. Fast screening and analysis (-omics) methods and metabolome-wide mathematical models are promising techniques. An integrated systems approach of these techniques drives diversity and quantity of several new biofuel compounds. This review will cover the recent technological developments that support improvement of the advanced biofuels 1-butanol, biodiesels and jetfuels. Copyright © 2011 Elsevier Ltd. All rights reserved.
Intercultural Education for the Mississippi Air National Guard (Coronet Gyro).
1980-10-01
Divide dough into thirds and roll each part into a strip about 18 inches long. Braid loosely on a greased cookie sheet. Cover with a cloth and let rise...and American) such as, candy, cookies , toilet articles, magazines, and cigarettes, but you will need Greek Drachmaes to barter with. 19. WHAT KIND OF...flour 1 teaspoon salt cup lukewarm water 2 tablespoons salad oil Sift flour and salt into a bowl. Gradually add water, stirring to make a stiff dough
1975-03-01
serves 8). 10. Add cooked dough . (See topping procedure). 11. Cover, label and place in blast freezer. Totals Rotes: 1. Reheating...3. Gradually add cold water and mix only enough to form a soft dough . 4. Place dough on a lightly floured board, kneeding lightly about 1...minute or until dough Is smooth. 5. Roll out to a uniform thickness of 1/4 inch. 6. Cut into 2 i/4-inch diameter biscuits. 7. Bake for 15 minutes in
Kuwait Oil Fields as seen from STS-58
1993-10-20
STS058-73-054 (18 Oct-1 Nov 1993) --- A clear view of the northern Kuwaiti coast shows the southern part of Kuwait City, and the major oil fields to the south. Oil-laden sands, where wells were set ablaze during the Gulf War in 1991, are visible south of Kuwait City as a dark, elongated patch surrounded by light-colored sand. Oil-stained sand between well sites (dots) and criss-crossing roads is gradually being covered by clean sand carried by strong, seasonal northwest winds.
Reducing Stressful Aspects of Information Technology in Public Services.
ERIC Educational Resources Information Center
Quinn, Brian
1995-01-01
Identifies sources of technological stress for public services librarians and patrons and proposes ways to reduce stress, including communicating with staff, implementing a system gradually, providing adequate training, creating proper documentation, planning, considering ergonomics in hardware and software selection, selecting a good interface,…
Modeling the influence of snow cover temperature and water content on wet-snow avalanche runout
NASA Astrophysics Data System (ADS)
Valero, Cesar Vera; Wever, Nander; Christen, Marc; Bartelt, Perry
2018-03-01
Snow avalanche motion is strongly dependent on the temperature and water content of the snow cover. In this paper we use a snow cover model, driven by measured meteorological data, to set the initial and boundary conditions for wet-snow avalanche calculations. The snow cover model provides estimates of snow height, density, temperature and liquid water content. This information is used to prescribe fracture heights and erosion heights for an avalanche dynamics model. We compare simulated runout distances with observed avalanche deposition fields using a contingency table analysis. Our analysis of the simulations reveals a large variability in predicted runout for tracks with flat terraces and gradual slope transitions to the runout zone. Reliable estimates of avalanche mass (height and density) in the release and erosion zones are identified to be more important than an exact specification of temperature and water content. For wet-snow avalanches, this implies that the layers where meltwater accumulates in the release zone must be identified accurately as this defines the height of the fracture slab and therefore the release mass. Advanced thermomechanical models appear to be better suited to simulate wet-snow avalanche inundation areas than existing guideline procedures if and only if accurate snow cover information is available.
NASA Astrophysics Data System (ADS)
Li, Xinghua; Fu, Wenxuan; Shen, Huanfeng; Huang, Chunlin; Zhang, Liangpei
2017-08-01
Monitoring the variability of snow cover is necessary and meaningful because snow cover is closely connected with climate and ecological change. In this work, 500 m resolution MODIS daily snow cover products from 2000 to 2014 were adopted to analyze the status in Hengduan Mountains. In order to solve the spatial discontinuity caused by clouds in the products, we propose an adaptive spatio-temporal weighted method (ASTWM), which is based on the initial result of a Terra and Aqua combination. This novel method simultaneously considers the temporal and spatial correlations of the snow cover. The simulated experiments indicate that ASTWM removes clouds completely, with a robust overall accuracy (OA) of above 93% under different cloud fractions. The spatio-temporal variability of snow cover in the Hengduan Mountains was investigated with two indices: snow cover days (SCD) and snow fraction. The results reveal that the annual SCD gradually increases and the coefficient of variation (CV) decreases with elevation. The pixel-wise trends of SCD first rise and then drop in most areas. Moreover, intense intra-annual variability of the snow fraction occurs from October to March, during which time there is abundant snow cover. The inter-annual variability, which mainly occurs in high elevation areas, shows an increasing trend before 2004/2005 and a decreasing trend after 2004/2005. In addition, the snow fraction responds to the two climate factors of air temperature and precipitation. For the intra-annual variability, when the air temperature and precipitation decrease, the snow cover increases. Besides, precipitation plays a more important role in the inter-annual variability of snow cover than temperature.
Estimating Sediment Losses Generated from Highway Cut and Fill Slopes in the Lake Tahoe Basin
DOT National Transportation Integrated Search
2014-12-01
Lake Tahoes famed water clarity has gradually declined over the last 50 years, partially as a result of fine sediment particle (FSP, < 16 micrometers in diameter) contributions from urban stormwater. Of these urban sources, highway cut and fill sl...
Production of Spirulina biomass: maintenance of Monoalgal culture outdoors
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vonshak, A.; Abeliovich, A.; Boussiba, S.
1983-02-01
The effects of sodium bicarbonate concentration, population density, and temperature on the maintenance of an outdoor monoculture of the cyanobacterium Spirulina platensis were studied. A clear response by Spirulina to the concentration of bicarbonate was evident, with 0.2M bicarbonate representing the lowest concentration in which a monoculture could be maintained. When the temperatures fell during the winter period to some 20-25/sup 0/C below the optimum for Spirulina. Chlorella sp. gradually increased and became the dominant species in the culture. Raising the temperature by covering the pond with transparent polyethylene resulted in a sharp decline in the population of Chlorella, andmore » a gradual resumption of species dominance by Spirulina. In winter, there was an inverse relationship in the pond between the population density of Spirulina and the extent of contamination by Chlorella sp., but no such effect was observed under field conditions at temperatures higher than 25/sup 0/C.« less
Florid urticarial vasculitis heralding a flare up of ulcerative colitis.
Boules, Evon; Lyon, Calum
2014-12-22
A 75-year-old man with ulcerative colitis (UC) and diet controlled diabetes mellitus presented with a 3-week history of slightly itchy, red plaques on both lower limbs ascending gradually to cover the trunk and arms. One week later, he developed a flare up of his UC. Routine blood tests showed modest drop in haemoglobin (122 g/L) and C reactive protein (85 mg/L). Serology was remarkable for high antiproteinase 3 (c-ANCA). Serum electrophoresis showed a mildly positive paraprotein band (γ region). Stool culture was negative. Urine analysis showed proteinuria. Skin biopsy showed features of urticarial vasculitis (UV). He underwent a flexible sigmoidoscopy after the flare up showed mildly active UC. The patient was given hydrocortisone for 7 days and then prednisolone. Both rash and UC subsided. Electrophoresis was repeated 4 weeks later showing normal pattern. Prednisolone has been gradually reduced. Although rare, UV can be considered as one of the skin manifestations of UC. 2014 BMJ Publishing Group Ltd.
Vogelmann, James E.; Xian, George; Homer, Collin G.; Tolk, Brian
2012-01-01
The focus of the study was to assess gradual changes occurring throughout a range of natural ecosystems using decadal Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper Plus (ETM +) time series data. Time series data stacks were generated for four study areas: (1) a four scene area dominated by forest and rangeland ecosystems in the southwestern United States, (2) a sagebrush-dominated rangeland in Wyoming, (3) woodland adjacent to prairie in northwestern Nebraska, and (4) a forested area in the White Mountains of New Hampshire. Through analyses of time series data, we found evidence of gradual systematic change in many of the natural vegetation communities in all four areas. Many of the conifer forests in the southwestern US are showing declines related to insects and drought, but very few are showing evidence of improving conditions or increased greenness. Sagebrush communities are showing decreases in greenness related to fire, mining, and probably drought, but very few of these communities are showing evidence of increased greenness or improving conditions. In Nebraska, forest communities are showing local expansion and increased canopy densification in the prairie–woodland interface, and in the White Mountains high elevation understory conifers are showing range increases towards lower elevations. The trends detected are not obvious through casual inspection of the Landsat images. Analyses of time series data using many scenes and covering multiple years are required in order to develop better impressions and representations of the changing ecosystem patterns and trends that are occurring. The approach described in this paper demonstrates that Landsat time series data can be used operationally for assessing gradual ecosystem change across large areas. Local knowledge and available ancillary data are required in order to fully understand the nature of these trends.
A Cognitive and Communications System of Behavior.
ERIC Educational Resources Information Center
Rose, Bruce J.
This research examined the nature of the "self-fulfilling prophecy" by investigating how the gradual accumulation of information and the relationship of the source and content of information may affect teachers' perceptions and ratings of trust, social ability, and academic ability of individual students. The study sought to answer two…
Verheyen, A; Vanparijs, O; Borgers, M; Thienpont, D
1978-06-01
The time-related topographical changes in mature cysticerci of Taenia taeniaformis induced after medication of infected mice with 250 ppm of mebendazole are described. The changes included the gradual disappearance of microtriches and progressive degeneration of the tegment resulting in an irregular surface with grooves, holes, and craterlike structures. Host cells adhered to the altered areas and the number of these cells increased when more severe changes became apparent. Finally the necrotized cysticerci, which lost their tegument completely, were almost entirely covered with adhesive host cells. A difference in the time sequence of the reported changes occurred between the scolex, the pseudoproglottids, and the bladder. This difference in susceptibility towards the drug between the three parts of the parasite in relation to the morphology of their microtrichous covering is discussed.
NASA Astrophysics Data System (ADS)
Arppe, Laura; Kurki, Eija; Wooller, Matthew; Luoto, Tomi; Zajączkowski, Marek; Ojala, Antti
2017-04-01
The oxygen isotope composition of head capsule chitin of chironomid larvae picked from a sediment core covering the past 5500 years from lake Svartvatnet in southern Spitsbergen was used to reconstruct the isotopic composition of oxygen in lake water (δ18Olw) and local precipitation. Consistent with the gradual cooling of climate over the Neoglacial period, the δ18Olw record displays a gentle decreasing trend over the study period. The Svartvatnet δ18Olwrecord shows a maximum at ca. 1900-1800 cal BP, consistent with the timing of the Roman Warm Period, and three negative excursions increasing in intensity towards the present-day at 3400-3200, 1250-1100 and 350-50 cal BP, which are tentatively linked to multidecadal periods of low solar activity amplified by oceanic and atmospheric feedbacks. The time period of the Little Ice Age shows a two-step decrease in δ18Olwvalues, with a remarkable, 8-9‰ drop at 350-50 cal BP construed to predominantly represent significantly decreased winter temperatures during a period of increased seasonal differences and extended sea ice cover inducing changes in moisture source regions. Similarity of the trends between the δ18Olwrecord and a July-T reconstruction based on chironomid assemblages (Luoto et al., in review) from the same core suggests that air temperature exerts a significant control over the δ18Olwvalues, but the record is most likely influenced by changes in sea ice extent and possibly the seasonal distribution of precipitation. Reference: Luoto TP, Ojala A, Brooks S et al. Synchronized proxy-based temperature reconstructions reveal mid-to late Holocene climate oscillations in High Arctic Svalbard. Journal of Quaternary Science, submitted.
NASA Astrophysics Data System (ADS)
Gabtni, H.; Jallouli, C.; Mickus, K. L.; Zouari, H.; Turki, M. M.
2006-03-01
Gravity and magnetic data were analyzed to add constraints on the location and nature of the Telemzan-Ghadames boundary (TGB) and structure of the Ghadames basin in southern Tunisia. TGB is the boundary between the thick sedimentary cover of the intracratonic Ghadames basin to the south and the thin sedimentary cover of the Saharan platform to the north. The upward continuation of the Bouguer gravity anomalies showed that the TGB is a regional geophysical feature that may have controlled the amount of sediment being deposited both north and south of the boundary and the tectonic environment in the region since Paleozoic time. To emphasize the shorter wavelength gravity and magnetic anomalies, a series of gray scale images of the directional horizontal gradients were constructed that determined a series of previously unknown east-west-trending gravity and magnetic anomalies south of 31.6°N that correspond to lineaments seen on a Landsat 7 image and the location of the TGB. Also, an edge-enhancement analysis illustrated the same linear gravity anomalies and showed the subbasins and uplifts within the Ghadames basin had source depths of between 0.5 and 3.4 km. A north-south trending gravity model showed that the TGB is a relatively gradual feature (possibly basement stepped down by relatively low-displacement faulting) controlling the subsidence of the main Ghadames basin and confirms the edge-enhancement analysis that subbasin S3 and uplift U1 are the main structural features within the Ghadames basin. The knowledge of basement architecture of the Ghadames basin is important for future petroleum exploration within this intracratonic basin.
From sink to source: Regional variation in U.S. forest carbon futures
Wear, David N.; Coulston, John W.
2015-01-01
The sequestration of atmospheric carbon (C) in forests has partially offset C emissions in the United States (US) and might reduce overall costs of achieving emission targets, especially while transportation and energy sectors are transitioning to lower-carbon technologies. Using detailed forest inventory data for the conterminous US, we estimate forests’ current net sequestration of atmospheric C to be 173 Tg yr−1, offsetting 9.7% of C emissions from transportation and energy sources. Accounting for multiple driving variables, we project a gradual decline in the forest C emission sink over the next 25 years (to 112 Tg yr−1) with regional differences. Sequestration in eastern regions declines gradually while sequestration in the Rocky Mountain region declines rapidly and could become a source of atmospheric C due to disturbances such as fire and insect epidemics. C sequestration in the Pacific Coast region stabilizes as forests harvested in previous decades regrow. Scenarios simulating climate-induced productivity enhancement and afforestation policies increase sequestration rates, but would not fully offset declines from aging and forest disturbances. Separating C transfers associated with land use changes from sequestration clarifies forests’ role in reducing net emissions and demonstrates that retention of forest land is crucial for protecting or enhancing sink strength. PMID:26558439
From sink to source: Regional variation in U.S. forest carbon futures.
Wear, David N; Coulston, John W
2015-11-12
The sequestration of atmospheric carbon (C) in forests has partially offset C emissions in the United States (US) and might reduce overall costs of achieving emission targets, especially while transportation and energy sectors are transitioning to lower-carbon technologies. Using detailed forest inventory data for the conterminous US, we estimate forests' current net sequestration of atmospheric C to be 173 Tg yr(-1), offsetting 9.7% of C emissions from transportation and energy sources. Accounting for multiple driving variables, we project a gradual decline in the forest C emission sink over the next 25 years (to 112 Tg yr(-1)) with regional differences. Sequestration in eastern regions declines gradually while sequestration in the Rocky Mountain region declines rapidly and could become a source of atmospheric C due to disturbances such as fire and insect epidemics. C sequestration in the Pacific Coast region stabilizes as forests harvested in previous decades regrow. Scenarios simulating climate-induced productivity enhancement and afforestation policies increase sequestration rates, but would not fully offset declines from aging and forest disturbances. Separating C transfers associated with land use changes from sequestration clarifies forests' role in reducing net emissions and demonstrates that retention of forest land is crucial for protecting or enhancing sink strength.
Shafiei, Rasoul; Zarmehrkhorshid, Raziyeh; Mounir, Majid; Thonart, Philippe; Delvigne, Frank
2017-05-01
Much research has been conducted about different types of fermentation at high temperature, but only a few of them have studied cell viability changes during high-temperature fermentation. In this study, Acetobacter senegalensis, a thermo-tolerant strain, was used for gluconic acid production at 38 °C. The influences of different carbon sources and physicochemical conditions on cell viability and the resuscitation of viable but nonculturable (VBNC) cells formed during fermentation were studied. Based on the obtained results, A. senegalensis could oxidize 95 g l - 1 glucose to gluconate at 38 °C (pH 5.5, yield 83%). However, despite the availability of carbon and nitrogen sources, the specific rates of glucose consumption (q s ) and gluconate production (q p ) reduced progressively. Interestingly, gradual q s and q p reduction coincided with gradual decrease in cellular dehydrogenase activity, cell envelope integrity, and cell culturability as well as with the formation of VBNC cells. Entry of cells into VBNC state during stationary phase partly stemmed from high fermentation temperature and long-term oxidation of glucose, because just about 48% of VBNC cells formed during stationary phase were resuscitated by supplementing the culture medium with an alternative favorite carbon source (low concentration of ethanol) and/or reducing incubation temperature to 30 °C. This indicates that ethanol, as a favorable carbon source, supports the repair of stressed cells. Since formation of VBNC cells is often inevitable during high-temperature fermentation, using an alternative carbon source together with changing physicochemical conditions may enable the resuscitation of VBNC cells and their use for several production cycles.
NASA Technical Reports Server (NTRS)
Barnes, J. C. (Principal Investigator)
1980-01-01
The author has identified the following significant results. Analysis of HCMM digital thermal data for daytime passes over the Salt-Verde Watershed area on five dates show a gradual depletion of snow cover in the watershed (and in the Little Colorado Watershed to the north) from a maximum on February 9th to a nearly complete disappearance of the snow pack by April 15th. Temperature contours correspond closely with the snowline observed in the visible image.
Ankersen, Jeppe; Grogan, Kenneth; Mertz, Ole; Fensholt, Rasmus; Castella, Jean-Christophe; Lestrelin, Guillaume; Nguyen, Dinh Tien; Danielsen, Finn; Brofeldt, Søren; Rasmussen, Kjeld
2015-05-01
One of the prerequisites of the REDD+ mechanism is to effectively predict business-as-usual (BAU) scenarios for change in forest cover. This would enable estimation of how much carbon emission a project could potentially prevent and thus how much carbon credit should be rewarded. However, different factors like forest degradation and the lack of linearity in forest cover transitions challenge the accuracy of such scenarios. Here we predict and validate such BAU scenarios retrospectively based on forest cover changes at village and district level in North Central Vietnam. With the government's efforts to increase the forest cover, land use policies led to gradual abandonment of shifting cultivation since the 1990s. We analyzed Landsat images from 1973, 1989, 1998, 2000, and 2011 and found that the policies in the areas studied did lead to increased forest cover after a long period of decline, but that this increase could mainly be attributed to an increase in open forest and shrub areas. We compared Landsat classifications with participatory maps of land cover/use in 1998 and 2012 that indicated more forest degradation than was captured by the Landsat analysis. The BAU scenarios were heavily dependent on which years were chosen for the reference period. This suggests that hypothetical REDD+ activities in the past, when based on the remote sensing data available at that time, would have been unable to correctly estimate changes in carbon stocks and thus produce relevant BAU scenarios.
NASA Astrophysics Data System (ADS)
Ankersen, Jeppe; Grogan, Kenneth; Mertz, Ole; Fensholt, Rasmus; Castella, Jean-Christophe; Lestrelin, Guillaume; Nguyen, Dinh Tien; Danielsen, Finn; Brofeldt, Søren; Rasmussen, Kjeld
2015-05-01
One of the prerequisites of the REDD+ mechanism is to effectively predict business-as-usual (BAU) scenarios for change in forest cover. This would enable estimation of how much carbon emission a project could potentially prevent and thus how much carbon credit should be rewarded. However, different factors like forest degradation and the lack of linearity in forest cover transitions challenge the accuracy of such scenarios. Here we predict and validate such BAU scenarios retrospectively based on forest cover changes at village and district level in North Central Vietnam. With the government's efforts to increase the forest cover, land use policies led to gradual abandonment of shifting cultivation since the 1990s. We analyzed Landsat images from 1973, 1989, 1998, 2000, and 2011 and found that the policies in the areas studied did lead to increased forest cover after a long period of decline, but that this increase could mainly be attributed to an increase in open forest and shrub areas. We compared Landsat classifications with participatory maps of land cover/use in 1998 and 2012 that indicated more forest degradation than was captured by the Landsat analysis. The BAU scenarios were heavily dependent on which years were chosen for the reference period. This suggests that hypothetical REDD+ activities in the past, when based on the remote sensing data available at that time, would have been unable to correctly estimate changes in carbon stocks and thus produce relevant BAU scenarios.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Koivisto, H., E-mail: hannu.koivisto@phys.jyu.fi; Kalvas, T.; Tarvainen, O.
Several ion source related research and development projects are in progress at the Department of Physics, University of Jyväskylä (JYFL). The work can be divided into investigation of the ion source plasma and development of ion sources, ion beams, and diagnostics. The investigation covers the Electron Cyclotron Resonance Ion Source (ECRIS) plasma instabilities, vacuum ultraviolet (VUV) and visible light emission, photon induced electron emission, and the development of plasma diagnostics. The ion source development covers the work performed for radiofrequency-driven negative ion source, RADIS, beam line upgrade of the JYFL 14 GHz ECRIS, and the development of a new room-temperature-magnetmore » 18 GHz ECRIS, HIISI.« less
NASA Technical Reports Server (NTRS)
Ko, Yuan-Kuen; Tylka, Allan J.; Ng, Chee K.; Wang, Yi-Ming; Dietrich, William F.
2013-01-01
Gradual solar energetic particle (SEP) events are those in which ions are accelerated to their observed energies by interactions with a shock driven by a fast coronal mass-ejection (CME). Previous studies have shown that much of the observed event-to-event variability can be understood in terms of shock speed and evolution in the shock-normal angle. But an equally important factor, particularly for the elemental composition, is the origin of the suprathermal seed particles upon which the shock acts. To tackle this issue, we (1) use observed solar-wind speed, magnetograms, and the PFSS model to map the Sun-L1 interplanetary magnetic field (IMF) line back to its source region on the Sun at the time of the SEP observations; and (2) then look for correlation between SEP composition (as measured by Wind and ACE at approx. 2-30 MeV/nucleon) and characteristics of the identified IMF-source regions. The study is based on 24 SEP events, identified as a statistically-significant increase in approx. 20 MeV protons and occurring in 1998 and 2003-2006, when the rate of newly-emergent solar magnetic flux and CMEs was lower than in solar-maximum years and the field-line tracing is therefore more likely to be successful. We find that the gradual SEP Fe/O is correlated with the field strength at the IMF-source, with the largest enhancements occurring when the footpoint field is strong, due to the nearby presence of an active region. In these cases, other elemental ratios show a strong charge-to-mass (q/M) ordering, at least on average, similar to that found in impulsive events. These results lead us to suggest that magnetic reconnection in footpoint regions near active regions bias the heavy-ion composition of suprathermal seed ions by processes qualitatively similar to those that produce larger heavy-ion enhancements in impulsive SEP events. To address potential technical concerns about our analysis, we also discuss efforts to exclude impulsive SEP events from our event sample.
NASA Astrophysics Data System (ADS)
Tylka, A. J.; Ko, Y.; Ng, C. K.; Wang, Y.; Dietrich, W. F.
2013-12-01
Gradual solar energetic particle (SEP) events are those in which ions are accelerated to their observed energies by interactions with a shock driven by a fast coronal mass-ejection (CME). Previous studies have shown that much of the observed event-to-event variability can be understood in terms of shock speed and evolution in the shock-normal angle. But an equally important factor, particularly for the elemental composition, is the origin of the suprathermal seed particles upon which the shock acts. To tackle this issue, we (1) use observed solar-wind speed, magnetograms, and the PFSS model to map the Sun-L1 interplanetary magnetic field (IMF) line back to its source region on the Sun at the time of the SEP observations; and (2) then look for correlation between SEP composition (as measured by Wind and ACE at ~2-30 MeV/nucleon) and characteristics of the identified IMF-source regions. The study is based on 24 SEP events, identified as a statistically-significant increase in ~20 MeV protons and occurring in 1998 and 2003-2006, when the rate of newly-emergent solar magnetic flux and CMEs was lower than in solar-maximum years and the field-line tracing is therefore more likely to be successful. We find that the gradual SEP Fe/O is correlated with the field strength at the IMF-source, with the largest enhancements occurring when the footpoint field is strong, due to the nearby presence of an active region. In these cases, other elemental ratios show a strong charge-to-mass (q/M) ordering, at least on average, similar to that found in impulsive events. These results lead us to suggest that magnetic reconnection in footpoint regions near active regions bias the heavy-ion composition of suprathermal seed ions by processes qualitatively similar to those that produce larger heavy-ion enhancements in impulsive SEP events. To address potential technical concerns about our analysis, we also discuss efforts to exclude impulsive SEP events from our event sample.
Slow recovery in desert perennial vegetation following prolonged human disturbance
Guo, Q.
2004-01-01
Questions: How long may it take for desert perennial vegetation to recover from prolonged human disturbance and how do different plant community variables (i.e. diversity, density and cover) change during the recovery process? Location: Sonoran Desert, Arizona, USA. Methods: Since protection from grazing from 1907 onwards, plant diversity, density and cover of perennial species were monitored intermittently on ten 10 m x 10 m permanent plots on Tumamoc Hill, Tucson, Arizona, USA. Results: The study shows an exceptionally slow recovery of perennial vegetation from prolonged heavy grazing and other human impacts. Since protection, overall species richness and habitat heterogeneity at the study site continued to increase until the 1960s when diversity, density and cover had been stabilized. During the same period, overall plant density and cover also increased. Species turnover increased gradually with time but no significant relation between any of the three community variables and precipitation or Palmer Drought Severity Index (PDSI) was detected. Conclusions: It took more than 50 yr for the perennial vegetation to recover from prolonged human disturbance. The increases in plant species richness, density, and cover of the perennial vegetation were mostly due to the increase of herbaceous species, especially palatable species. The lack of a clear relationship between environment (e.g. precipitation) and community variables suggests that site history and plant life history must be taken into account in examining the nature of vegetation recovery processes after disturbance.
Growth methods for controlled large-area fabrication of high-quality graphene analogs
Najmaei, Sina; Liu, Zheng; Ajayan, Pulickel M.; Lou, Jun
2017-02-28
In some embodiments, the present disclosure pertains to methods of growing chalcogen-linked metallic films on a surface in a chamber. In some embodiments, the method comprises placing a metal source and a chalcogen source in the chamber, and gradually heating the chamber, where the heating leads to the chemical vapor deposition of the chalcogen source and the metal source onto the surface, and facilitates the growth of the chalcogen-linked metallic film from the chalcogen source and the metal source on the surface. In some embodiments, the chalcogen source comprises sulfur, and the metal source comprises molybdenum trioxide. In some embodiments, the growth of the chalcogen-linked metallic film occurs by formation of nucleation sites on the surface, where the nucleation sites merge to form the chalcogen-linked metallic film. In some embodiments, the formed chalcogen-linked metallic film includes MoS.sub.2.
Fuchs-Kliewer phonons of H-covered and clean GaN(1 1 bar 00)
NASA Astrophysics Data System (ADS)
Rink, M.; Himmerlich, M.; Krischok, S.; Kröger, J.
2018-01-01
Inelastic electron scattering is used to study surface phonon polaritons on H-covered and clean GaN(1 1 bar 00) surfaces. The Fuchs-Kliewer phonon of GaN(1 1 bar 00) -H gives rise to characteristic signatures of its single and multiple excitation in specular electron energy loss spectra. The loss intensities for multi-phonon scattering processes decrease according to a Poisson distribution. Vibrational spectra of this surface are invariant on the time scale of days reflecting its chemical passivation by the H layer. In contrast, vibrational spectra of pristine GaN(1 1 bar 00) are subject to a pronounced temporal evolution where spectroscopic weight is gradually shifted towards the multiple excitation of the Fuchs-Kliewer phonon. As a consequence, the monotonous decrease of the cross section for multiple quantum excitation as observed for the H-covered surface is not applicable. This remarkable effect is particularly strong in spectra acquired at low primary energies of incident electrons, which hints at processes occurring in the very surface region. Scenarios that may contribute to these observations are discussed.
Effect of water content on the water repellency for hydrophobized sands
NASA Astrophysics Data System (ADS)
Subedi, S.; Kawamoto, K.; Kuroda, T.; Moldrup, P.; Komatsu, T.
2011-12-01
Alternative earthen covers such as capillary barriers (CBs) and evapotranspirative covers are recognized as useful technical and low-cost solutions for limiting water infiltration and controlling seepage flow at solid waste landfills in semi-arid and arid regions. However, their application to the landfills at wet regions seems to be matter of concern due to loss of their impending capability under high precipitation. One of the possible techniques to enhance the impermeable properties of CBs is to alter soil grain surfaces to be water-repellent by mixing/coating hydrophobic agents (HAs). In order to examine a potential use of model sands hydrophobized with locally available and environmental-friendly HAs such as oleic acid (OA) and stearic acid (SA) for hydrophobic CBs. In the present study, we first characterized the effect of water content on the degree of water repellency (WR) for hydrophobized sands and volcanic ash soil at different depth. Secondly, the time dependency of the contact angle in hydrophobized sands and volcanic ash soils at different water content was evaluated. Further, the effects of hydrophobic organic matter contents on the WR of hydrophobized sands were investigated by horizontal infiltration test. We investigated the degree of WR as functions of volumetric water content (θ) of a volcanic ash soil samples from different depth and water adjusted hydrophobized sand samples with different ratio of HAs by using sessile drop method (SDM). The initial contact angle (αi) measured from SDM decreased gradually with increasing water content in OA and SA coated samples. Measured αi values for volcanic ash soils increased with increasing water content and reached a peak values of 111.7o at θ= 0.325 cm3 cm-3, where-after αi gradually decreased. Each test sample exhibited sharp decrease in contact angle with time at higher water content. Sorptivity values for oleic acid coated samples decreased with increasing HA content and reached the minimum value of 0.068 cm s-1/2 at 1 g HA kg-1 sand, and then gradually increased.
Jansen, Louisa J M; Carrai, Giancarlo; Morandini, Luca; Cerutti, Paolo O; Spisni, Andrea
2006-08-01
In the turmoil of a rapidly changing economy the Albanian government needs accurate and timely information for management of their natural resources and formulation of land-use policies. The transformation of the forestry sector has required major changes in the legal, regulatory and management framework. The World Bank financed Albanian National Forest Inventory project provides an analysis of spatially explicit land-cover/use change dynamics in the period 1991-2001 using the FAO/UNEP Land Cover Classification System for codification of classes, satellite remote sensing and field survey for data collection and elements of the object-oriented geo-database approach to handle changes as an evolution of land-cover/use objects, i.e. polygons, over time to facilitate change dynamics analysis. Analysis results at national level show the trend of natural resources depletion in the form of modifications and conversions that lead to a gradual shift from land-cover/use types with a tree cover to less dense tree covers or even a complete removal of trees. Policy failure (e.g., corruption, lack of law enforcement) is seen as the underlying cause. Another major trend is urbanisation of areas near large urban centres that change urban-rural linkages. Furthermore, after privatisation agricultural areas increased in the hills where environmental effects may be detrimental, while prime agricultural land in the plains is lost to urbanisation. At district level, the local variability of spatially explicit land-cover/use changes shows different types of natural resources depletion. The distribution of changes indicates a regional prevalence, thus a decentralised approach to the natural resources management could be advocated.
INFLUENCE OF REMOTE SENSING IMAGERY SOURCE ON QUANTIFICATION OF RIPARIAN LAND COVER/LAND USE
This paper compares approaches to quantifying land cover/land use (LCLU) in riparian corridors of 23 watersheds in Oregon's Willamette Valley using aerial photography (AP) and Thematic Mapper (TM) imagery. For each imagery source, we quantified LCLU adjacent to stream networks ac...
40 CFR 63.11436 - What parts of my plant does this subpart cover?
Code of Federal Regulations, 2010 CFR
2010-07-01
... CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Clay Ceramics... subpart cover? (a) This subpart applies to any existing or new affected source located at a clay ceramics... glazed ceramic ware located at a clay ceramics manufacturing facility. (c) An affected source is existing...
40 CFR 72.65 - Public notice of opportunities for public comment.
Code of Federal Regulations, 2011 CFR
2011-07-01
...) AIR PROGRAMS (CONTINUED) PERMITS REGULATION Federal Acid Rain Permit Issuance Procedures § 72.65... area where the source covered by the Acid Rain permit application is located or in a State publication... designated representative for the affected source. (3) Identification of each unit covered by the Acid Rain...
40 CFR 72.65 - Public notice of opportunities for public comment.
Code of Federal Regulations, 2013 CFR
2013-07-01
...) AIR PROGRAMS (CONTINUED) PERMITS REGULATION Federal Acid Rain Permit Issuance Procedures § 72.65... area where the source covered by the Acid Rain permit application is located or in a State publication... designated representative for the affected source. (3) Identification of each unit covered by the Acid Rain...
40 CFR 72.65 - Public notice of opportunities for public comment.
Code of Federal Regulations, 2012 CFR
2012-07-01
...) AIR PROGRAMS (CONTINUED) PERMITS REGULATION Federal Acid Rain Permit Issuance Procedures § 72.65... area where the source covered by the Acid Rain permit application is located or in a State publication... designated representative for the affected source. (3) Identification of each unit covered by the Acid Rain...
40 CFR 72.65 - Public notice of opportunities for public comment.
Code of Federal Regulations, 2010 CFR
2010-07-01
...) AIR PROGRAMS (CONTINUED) PERMITS REGULATION Federal Acid Rain Permit Issuance Procedures § 72.65... area where the source covered by the Acid Rain permit application is located or in a State publication... designated representative for the affected source. (3) Identification of each unit covered by the Acid Rain...
49 CFR 173.124 - Class 4, Divisions 4.1, 4.2 and 4.3-Definitions.
Code of Federal Regulations, 2012 CFR
2012-10-01
... exothermic decomposition even without participation of oxygen (air). A material is excluded from this... external ignition source, can ignite within five (5) minutes after coming in contact with air when tested... material that through a process where the gradual reaction of that substance with oxygen (in air) generates...
The Sources and Experience of Anxiety in Practice Teaching.
ERIC Educational Resources Information Center
Sinclair, Ken; Nicoll, Vivienne
For most student teachers, practice teaching is a difficult and anxiety-provoking experience. Anxiety arises when feelings of self-adequacy and security are threatened. A survey of 84 teacher education majors shows that anxiety levels are often high immediately prior to the internship; however, the anxiety level gradually declines by the middle of…
Erosion processes and prediction in NW U.S. forests
W. J. Elliot; P. R. Robichaud; R. B. Foltz
2011-01-01
The greatest amounts of forest erosion usually follow infrequent wildfires. Sediment from these fires is gradually routed through the stream system. The forest road network is usually the second greatest source of sediment, generating sediment annually. Erosion rates associated with timber harvest, biomass removal, and prescribed fire are generally minimal with current...
Mule deer and elk winter diet as an indicator of habitat competition
Michael R. Frisina; Carl L. Wambolt; W. Wyatt Fraas; Glen Guenther
2008-01-01
Mule deer (Odocoileus hemionus) populations have gradually declined in recent decades, while elk (Cervus elaphus) have often increased throughout their common ranges. The cause is uncertain and a source of debate. Increasing elk numbers on these ungulate winter ranges may be causing competition for resources. We contrast winter...
Bobowski, Nuala
2015-01-01
Dietary salt reduction of Americans has been a focus of public health initiatives for more than 40 years primarily due to the association between high salt intake and development of hypertension. Despite past efforts, salt intake of Americans has remained at levels well above dietary recommendations, likely due in part to the hedonic appeal of salty taste. As such, in 2010 the Institute of Medicine suggested a strategy of gradual salt reduction of processed foods, the primary source of Americans’ dietary salt intake, via an approach intended to minimize impact on consumer acceptability of lower-sodium foods. This brief review discusses the ontogeny and development of human salt taste preference, the role of experience in shifting salt preference, and sources of dietary salt. Our current understanding of shifting human salt taste preference is discussed within the context of potential opportunities for success in reducing dietary salt, and gaps in the research that both limit our ability to predict effectiveness of gradual salt reduction and that need be addressed before a strategy to shift salt preference can realistically be implemented. PMID:26451233
Ying, Hangjun
2017-01-01
Abstract With the fast‐growing demand for green and safe energy sources, rechargeable ion batteries have gradually occupied the major current market of energy storage devices due to their advantages of high capacities, long cycling life, superior rate ability, and so on. Metallic Sn‐based anodes are perceived as one of the most promising alternatives to the conventional graphite anode and have attracted great attention due to the high theoretical capacities of Sn in both lithium‐ion batteries (LIBs) (994 mA h g−1) and sodium‐ion batteries (847 mA h g−1). Though Sony has used Sn–Co–C nanocomposites as its commercial LIB anodes, to develop even better batteries using metallic Sn‐based anodes there are still two main obstacles that must be overcome: poor cycling stability and low coulombic efficiency. In this review, the latest and most outstanding developments in metallic Sn‐based anodes for LIBs and SIBs are summarized. And it covers the modification strategies including size control, alloying, and structure design to effectually improve the electrochemical properties. The superiorities and limitations are analyzed and discussed, aiming to provide an in‐depth understanding of the theoretical works and practical developments of metallic Sn‐based anode materials. PMID:29201624
Ying, Hangjun; Han, Wei-Qiang
2017-11-01
With the fast-growing demand for green and safe energy sources, rechargeable ion batteries have gradually occupied the major current market of energy storage devices due to their advantages of high capacities, long cycling life, superior rate ability, and so on. Metallic Sn-based anodes are perceived as one of the most promising alternatives to the conventional graphite anode and have attracted great attention due to the high theoretical capacities of Sn in both lithium-ion batteries (LIBs) (994 mA h g -1 ) and sodium-ion batteries (847 mA h g -1 ). Though Sony has used Sn-Co-C nanocomposites as its commercial LIB anodes, to develop even better batteries using metallic Sn-based anodes there are still two main obstacles that must be overcome: poor cycling stability and low coulombic efficiency. In this review, the latest and most outstanding developments in metallic Sn-based anodes for LIBs and SIBs are summarized. And it covers the modification strategies including size control, alloying, and structure design to effectually improve the electrochemical properties. The superiorities and limitations are analyzed and discussed, aiming to provide an in-depth understanding of the theoretical works and practical developments of metallic Sn-based anode materials.
Matsumoto, H; Oguchi, Y; Miyake, Y; Masuda, Y; Masada, S; Kuno, Y; Shibahara, I; Takashima, K; Yamane, H; Yamagata, S; Noishiki, Y; Yamane, Y
1996-07-01
Canine pericardium which had been treated with polyepoxy compounds (Denacol EX-313) was used as a patch graft for the correction of experimentally-created diaphragmatic defects in five dogs belonging to the same litter. Clinical, macroscopic and histological examinations were conducted every month up to five months after suturing of the patch graft. Clinical examination of the patch graft showed no apparent abnormalities. Macroscopic examination conducted during autopsy showed that the patch graft maintained adequate elasticity for five months after suturing, the surface of the patch graft was covered with a thin membrane and neovascularization was observed. Histological examination showed that the surface of the patch graft was covered with a thin membrane. Inflammatory tissue reactions were observed at one month, but gradually decreased from the second month onwards. In addition, the patch graft had excellent tissue affinity.
Thin sheets achieve optimal wrapping of liquids
NASA Astrophysics Data System (ADS)
Paulsen, Joseph; Démery, Vincent; Davidovitch, Benny; Santangelo, Christian; Russell, Thomas; Menon, Narayanan
2015-03-01
A liquid drop can wrap itself in a sheet using capillary forces [Py et al., PRL 98, 2007]. However, the efficiency of ``capillary origami'' at covering the surface of a drop is hampered by the mechanical cost of bending the sheet. Thinner sheets deform more readily by forming small-scale wrinkles and stress-focussing patterns, but it is unclear how coverage efficiency competes with mechanical cost as thickness is decreased, and what wrapping shapes will emerge. We place a thin (~ 100 nm) polymer film on a drop whose volume is gradually decreased so that the sheet covers an increasing fraction of its surface. The sheet exhibits a complex sequence of axisymmetric and polygonal partially- and fully- wrapped shapes. Remarkably, the progression appears independent of mechanical properties. The gross shape, which neglects small-scale features, is correctly predicted by a simple geometric approach wherein the exposed area is minimized. Thus, simply using a thin enough sheet results in maximal coverage.
Chronic environmental stress enhances tolerance to seasonal gradual warming in marine mussels
Múgica, Maria; Izagirre, Urtzi; Sokolova, Inna M.
2017-01-01
In global climate change scenarios, seawater warming acts in concert with multiple stress sources, which may enhance the susceptibility of marine biota to thermal stress. Here, the responsiveness to seasonal gradual warming was investigated in temperate mussels from a chronically stressed population in comparison with a healthy one. Stressed and healthy mussels were subjected to gradual temperature elevation for 8 days (1°C per day; fall: 16–24°C, winter: 12–20°C, summer: 20–28°C) and kept at elevated temperature for 3 weeks. Healthy mussels experienced thermal stress and entered the time-limited survival period in the fall, became acclimated in winter and exhibited sublethal damage in summer. In stressed mussels, thermal stress and subsequent health deterioration were elicited in the fall but no transition into the critical period of time-limited survival was observed. Stressed mussels did not become acclimated to 20°C in winter, when they experienced low-to-moderate thermal stress, and did not experience sublethal damage at 28°C in summer, showing instead signs of metabolic rate depression. Overall, although the thermal threshold was lowered in chronically stressed mussels, they exhibited enhanced tolerance to seasonal gradual warming, especially in summer. These results challenge current assumptions on the susceptibility of marine biota to the interactive effects of seawater warming and pollution. PMID:28333994
Galvez, Miguel; Grossman, Kenneth; Betts, David
2013-11-12
There is herein described a lamp for providing white light comprising a plurality of light sources positioned on a substrate. Each of said light sources comprises a blue light emitting diode (LED) and a dome that substantially covers said LED. A first portion of said blue light from said LEDs is transmitted through said domes and a second portion of said blue light is converted into a red light by a first phosphor contained in said domes. A cover is disposed over all of said light sources that transmits at least a portion of said red and blue light emitted by said light sources. The cover contains a second phosphor that emits a yellow light in response to said blue light. The red, blue and yellow light combining to form the white light and the white light having a color rendering index (CRI) of at least about 80.
A new thermal shape memory Ti-Ni alloy stent covered with silicone.
Nakamura, T; Shimizu, Y; Ito, Y; Matsui, T; Okumura, N; Takimoto, Y; Ariyasu, T; Kiyotani, T
1992-01-01
An attempt was made to develop an airway stent for nonsurgical transluminal implantation using a bronchofiberscope. The stent is composed of a single wire with a diameter of 0.5 mm. The wire is made of thermal shape memory titanium nickel alloy, with a transition temperature of 25-30 degrees C. To avoid direct contact between the metal and the tissue, the wire is covered with a 300 microns thick coating of silicone. The stent is horseshoe shaped in cross-section. It is 15 mm in outer transverse diameter and 40 mm long. Ten stents were implanted in 10 dogs whose tracheal cartilages had been previously broken. The stents were first cooled in ice water to reduce their diameter and then inserted into the target site. The wire was warmed to body temperature and recovered its initial shape within 10 sec. The dogs were killed for examination between 1 week and 6 months after implantation. All the stents were located at the implantation sites and were patent. Tissue reactions, such as ulceration and granulation formation, were less severe than in those with previously implanted non-silicone covered stents. Microscopic observation showed that the wires became gradually covered with epithelium within 2 months. This transluminal technique for preserving airway patency shows promise for clinical application.
NASA Astrophysics Data System (ADS)
Lee, Yun Gon; Koo, Ja-Ho; Kim, Jhoon
2015-10-01
This study investigated how cloud fraction and snow cover affect the variation of surface ultraviolet (UV) radiation by using surface Erythemal UV (EUV) and Near UV (NUV) observed at the King Sejong Station, Antarctica. First the Radiative Amplification Factor (RAF), the relative change of surface EUV according to the total-column ozone amount, is compared for different cloud fractions and solar zenith angles (SZAs). Generally, all cloudy conditions show that the increase of RAF as SZA becomes larger, showing the larger effects of vertical columnar ozone. For given SZA cases, the EUV transmission through mean cloud layer gradually decreases as cloud fraction increases, but sometimes the maximum of surface EUV appears under partly cloudy conditions. The high surface EUV transmittance under broken cloud conditions seems due to the re-radiation of scattered EUV by cloud particles. NUV transmission through mean cloud layer also decreases as cloud amount increases but the sensitivity to the cloud fraction is larger than EUV. Both EUV and NUV radiations at the surface are also enhanced by the snow cover, and their enhancement becomes higher as SZA increases implying the diurnal variation of surface albedo. This effect of snow cover seems large under the overcast sky because of the stronger interaction between snow surface and cloudy sky.
An extended superhot solar flare X-ray source
NASA Technical Reports Server (NTRS)
Hudson, H. S.; Ohki, K. I.; Tsuneta, S.
1985-01-01
A superhot hard X-ray source in a solar flare occulted by the solar limb was identified. Its hard X-ray image was found to show great horizontal extent but little vertical extent. An H alpha brightening at the same limb position about an hour later suggests a multi-component loop prominence system, so that it appears that a superhot source can evolve in the same manner as a normal solar soft X-ray source. The assignment of plausiable values to physical parameters in the source suggests (from the simplest form of classical thermal-conduction theory) that either new physics will be required to suppress conduction, or else that gradual energy release well after the impulsive phase of the flare must occur. In this respect too, the superhot source appears to resemble ordinary soft X-ray sources, except of course that its temperature is higher.
Koivisto, H; Kalvas, T; Tarvainen, O; Komppula, J; Laulainen, J; Kronholm, R; Ranttila, K; Tuunanen, J; Thuillier, T; Xie, D; Machicoane, G
2016-02-01
Several ion source related research and development projects are in progress at the Department of Physics, University of Jyväskylä (JYFL). The work can be divided into investigation of the ion source plasma and development of ion sources, ion beams, and diagnostics. The investigation covers the Electron Cyclotron Resonance Ion Source (ECRIS) plasma instabilities, vacuum ultraviolet (VUV) and visible light emission, photon induced electron emission, and the development of plasma diagnostics. The ion source development covers the work performed for radiofrequency-driven negative ion source, RADIS, beam line upgrade of the JYFL 14 GHz ECRIS, and the development of a new room-temperature-magnet 18 GHz ECRIS, HIISI.
NASA Astrophysics Data System (ADS)
Alpert, Pinhas; Egert, Smadar; Uzan, Leenes
2017-04-01
On 7 Sep 2015 an unprecedented huge dust plume approached the SE Mediterranean basin from the northeast- Syria region. According to the Israeli meteorological service it is the first time in 75 years of measurements, that a dust storm reaches Israel early September, lasts several days and dust concentrations reach values 100 times the normal (1700µg/m3). Dust storms are normally monitored in the east Mediterranean using satellites and surface PM data. Obviously, these cannot show the vertical evolution of the dust including penetration, sinking and cleaning since vertical profiles are not available. High-resolution, micro Lidar Ceilometer network is gradually established in Israel. A few instruments of this network were already operational during the dust storm. The most crucial vertical information, monitored by these Ceilometers with 10m resolution vertically, every 16s, is analyzed. The difference in the cloud-layers allow the investigation of the high altitude of 1000m dust penetration, its sinking into the complex structured 250-500m mixed layer and the gradual 3D cleaning. This finding contradicts the conventional understanding that cleaning is due to gradual descent and shows not only the vertical fluctuation during the entire event but also the vertical rise to 2000m at the end of the event. The vertical information showed that the actual event period duration was 7 days, compared to only 90 hours based on traditional detectors. Is it a new dust source in the E. Mediterranean-long and short term trends?
NASA Astrophysics Data System (ADS)
Zhang, Yinsheng; Ma, Ning
2018-04-01
Changes in the extent and amount of snow cover in Eurasia are of great interest because of their vital impacts on the global climate system and regional water resource management. This study investigated the spatial and temporal variability of the snow cover extent (SCE) and snow water equivalent (SWE) of the continental Eurasia using the Northern Hemisphere Equal-Area Scalable Earth Grid (EASE-Grid) Weekly SCE data for 1972-2006 and the Global Monthly EASE-Grid SWE data for 1979-2004. The results indicated that, in general, the spatial extent of snow cover significantly decreased during spring and summer, but varied little during autumn and winter over Eurasia in the study period. The date at which snow cover began to disappear in spring has significantly advanced, whereas the timing of snow cover onset in autumn did not vary significantly during 1972-2006. The snow cover persistence period declined significantly in the western Tibetan Plateau as well as partial area of Central Asia and northwestern Russia, but varied little in other parts of Eurasia. "Snow-free breaks" (SFBs) with intermittent snow cover in the cold season were principally observed in the Tibetan Plateau and Central Asia, causing a low sensitivity of snow cover persistence period to the timings of snow cover onset and disappearance over the areas with shallow snow. The averaged SFBs were 1-14 weeks during the study period and the maximum intermittence could even reach 25 weeks in certain years. At a seasonal scale, SWE usually peaked in February or March, but fell gradually since April across Eurasia. Both annual mean and annual maximum SWE decreased significantly during 1979-2004 in most parts of Eurasia except for eastern Siberia as well as northwestern and northeastern China. The possible cross-platform inconsistencies between two passive microwave radiometers may cause uncertainties in the detected trends of SWE here, suggesting an urgent need of producing a long-term, more homogeneous SWE product in future.
Forecasting land cover change impacts on drinking water treatment costs in Minneapolis, Minnesota
NASA Astrophysics Data System (ADS)
Woznicki, S. A.; Wickham, J.
2017-12-01
Source protection is a critical aspect of drinking water treatment. The benefits of protecting source water quality in reducing drinking water treatment costs are clear. However, forecasting the impacts of environmental change on source water quality and its potential to influence future treatment processes is lacking. The drinking water treatment plant in Minneapolis, MN has recognized that land cover change threatens water quality in their source watershed, the Upper Mississippi River Basin (UMRB). Over 1,000 km2 of forests, wetlands, and grasslands in the UMRB were lost to agriculture from 2008-2013. This trend, coupled with a projected population increase of one million people in Minnesota by 2030, concerns drinking water treatment plant operators in Minneapolis with respect to meeting future demand for clean water in the UMRB. The objective of this study is to relate land cover change (forest and wetland loss, agricultural expansion, urbanization) to changes in treatment costs for the Minneapolis, MN drinking water utility. To do this, we first developed a framework to determine the relationship between land cover change and water quality in the context of recent historical changes and projected future changes in land cover. Next we coupled a watershed model, the Soil and Water Assessment Tool (SWAT) to projections of land cover change from the FOREcasting SCEnarios of Land-use Change (FORE-SCE) model for the mid-21st century. Using historical Minneapolis drinking water treatment data (chemical usage and costs), source water quality in the UMRB was linked to changes in treatment requirements as a function of projected future land cover change. These analyses will quantify the value of natural landscapes in protecting drinking water quality and future treatment processes requirements. In addition, our study provides the Minneapolis drinking water utility with information critical to their planning and capital improvement process.
Nakahara, Takehiro; Jinzaki, Masahiro; Niwamae, Nogiku; Saito, Yuuichirou; Arai, Masashi; Tsushima, Yoshito; Kuribayashi, Sachio; Kurabayashi, Masahiko
2014-01-01
Despite the improvement of cardiac CT, right heart visualization remains challenging. We herein describe a new method, called the time-adjusted gradual replacement injection protocol. The aim of this study was to compare this protocol with the split-bolus injection protocol. Fifty-two patients who had undergone dual-source cardiac CT were retrospectively recruited. Twenty-six patients were injected by using the split-bolus injection protocol, and 26 patients were injected by using the time-adjusted gradual replacement injection protocol. For this method, we injected contrast medium for 10 seconds at a flow rate of 0.07 × body weight mL/s, then gradually replaced the contrast material with saline until 2 seconds before finishing the scans. The CT attenuation was measured in 4 chambers, the aorta, and the coronary arteries. The visualization of the anatomic structures and the occurrence and severity of streak artifacts were scored for the cardiac structures in the heart. For the analyses, either Welch t-test or Student t-test was performed. In the right heart, the CT values and visualization scores were significantly higher in the time-adjusted replacement injection group than in the split-bolus injection group, whereas the artifact scores were comparable between the 2 groups. The CT values, visualization scores, and artifact scores of the left heart were not significantly different between the 2 groups. In this study, the time-adjusted gradual replacement injection protocol provided excellent attenuation for visualization of the right heart. This method may help to accurately evaluate the right cardiac anatomy and thereby identify any potential diseases. Copyright © 2014 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.
Evaluation of seven drought tolerant tree species for central California
E.G. McPherson; S. Albers
2014-01-01
Climate change poses challenges for the Southwest, where an already parched region is expected to get hotter and, in its southern half, significantly drier (Garfin et al. 2013). Increased heat and sustained drought will stress water sources and redefine urban landscapes. As landscapes gradually evolve from lush to xeric, tolerance of trees to water-related stress...
Erosion processes and prediction with WEPP technology in forests in the Northwestern U.S.
W. J. Elliot
2013-01-01
In the northwestern U.S., the greatest amounts of forest erosion usually follow infrequent wildfires. Sediment from these fires is gradually routed through the stream system. The forest road network is usually the second greatest source of sediment, generating sediment annually. Erosion rates associated with timber harvest, biomass removal, and prescribed fire are...
Peer Learning and Support of Technology in an Undergraduate Biology Course to Enhance Deep Learning
ERIC Educational Resources Information Center
Tsaushu, Masha; Tal, Tali; Sagy, Ornit; Kali, Yael; Gepstein, Shimon; Zilberstein, Dan
2012-01-01
This study offers an innovative and sustainable instructional model for an introductory undergraduate course. The model was gradually implemented during 3 yr in a research university in a large-lecture biology course that enrolled biology majors and nonmajors. It gives priority to sources not used enough to enhance active learning in higher…
ERIC Educational Resources Information Center
Yilmaz, Oguzhan
2016-01-01
The world has been changing, information sources have been diversifying; and the importance of reading book has been gradually increasing. Books' constituting a place in life children as vitally important in developing their learning and imagination depends upon their close surrounding and essentially their learning Turkish. Therefore, in this…
Novel Labels Support 10-Month-Olds' Attention to Novel Objects
ERIC Educational Resources Information Center
Mather, Emily; Plunkett, Kim
2010-01-01
What is the source of the "mutual exclusivity" bias whereby infants map novel labels onto novel objects? In an intermodal preferential looking task, we found that novel labels support 10-month-olds' attention to a novel object over a familiar object. In contrast, familiar labels and a neutral phrase gradually reduced attention to a novel object.…
The Impact of the Use of Energy Sources on the Quality of Life of Poor Communities
ERIC Educational Resources Information Center
Martins, John
2005-01-01
Over the last few decades, the energy literature has been dominated by a theory of transition. The theory of transition is based on the notion that households gradually ascend an "energy ladder", which begins with traditional biomass fuels (firewood and charcoal), moves through modern commercial fuels (kerosene and liquid petroleum gas…
[Water utilization characteristics of the degraded poplar shelterbelts in Zhangbei, Hebei, China.
Zhang, Huan; Cao, Jun; Wang, Hua Bing; Song, Bo; Jia, Guo Dong; Liu, Zi Qiang; Yu, Xin Xiao; Zeng, Jia
2018-05-01
In Zhangbei County, Hebei Province, poplar-dominated shelterbelts are degraded to different extents. Water availability is the main limiting factor for plant survival in arid areas. The purpose of this study was to reveal the relationship between water availability and poplar degradation. Based on the hydrogen and oxygen stable isotope techniques, we explored the water sources of Populus simonii under different degradation degrees by comparing the isotopic values of P. simonii xylem water with that in potential water source, and calculated the utilization ratio of each water source. The results showed that the water sources of poplar trees varied with degradation degree. The water sources of P. simonii gradually transferred from the deep layer to the surface layer with the increases of degradation. P. simonii with no degradation mainly absorbed soil water in the range of 320-400 cm, with the utilization rate being 25.1%. P. simonii with slight degradation mainly used soil water at depth of 120-180, 180-240 and 240-320 cm. The total utilization rate of three layers was close to 50.0%, with less utilization of water from other layers. The moderately degraded P. simonii mainly used soil water at depth of 20-40, 40-60 and 60-80 cm. The utilization rate of each layer was 17.5%-20.9%, and the contribution rate of soil water under 120 cm was less than 10.0%. The severely degraded P. simonii mainly used water from surface soil layer (0-20 cm), with the utilization rate being 30.4%, which was significantly higher than that of other water sources. The water sources of poplar shelter forests were gradually shallower during the process of degradation. However, the low soil water content in the shallow layer could not meet the normal water demand of poplar, which would accelerate the degradation and even decline of poplar.
NASA Astrophysics Data System (ADS)
Baranova, Alina; Schickhoff, Udo; Shunli, Wang; Ming, Jin
2015-04-01
Qilian Mountains are the water source region for the low arid reaches of HeiHe river basin (Gansu province, NW China). Due to overstocking and overgrazing during the last decades adverse ecological ef¬fects, in particular on soil properties and hydrological cycle, are to be expected in growing land areas. Vegetation cover is very important to prevent erosion process and to sustain stable subsurface runoff and ground water flow. The aim of this research is to identify plant communities, detecting grazing-induced and spatially differentiated changes in vegetation patterns, and to evaluate status of pasture land degradation.The study area is located in the spring/autumn pasture area of South Qilian Mountains between 2600-3600 m a.s.l., covering five main vegetation types: spruce forest, alpine shrubland, shrubby grassland, mountain grassland, degraded mountain grassland. In order to analyze gradual changes in vegetation patterns along altitudinal and grazing gradients and to classify related plant communities, quantitative and qualitative relevé data were collected (coverage, species composition, abundance of unpalatable plants, plant functional types, etc.). Vegetation was classified using hierarchical cluster analyses. Indirect Detrended Correspondence Analysis (DCA) was used to analyze variation in relationships between vegetation, environmental factors, and grazing impact. According to DCA results, distribution of the plant communities was strongly affected by altitude and exposition. Grassland floristic gradients showed greater dependence on grazing impact, which correlated contrarily with soil organic content, soil moisture and pH. Highest numbers of species richness and alpha diversity were detected in alpine shrubland vegetation type. Comparing the monitoring data for the recent nine years, a trend of deterioration, species successions and shift in dominant species becomes obvious. Species indicating degrading site environmental conditions were identified. Most of the grasslands have become secondary vegetation, with a considerable percentage of unpalatable, toxic and often thorny or spiny shrub and herb species that have a lower grazing value and rarely form a closed vegetation cover, at least in loess slopes. To prevent further degradation of the grassland and to sustain the diversity of the plant species (affecting the carrying capacity pastureland) appropriate pasture management strategy should be implemented.
Simulation of Glacial Cycles Before and After the Mid-Pleistocene Transition
NASA Astrophysics Data System (ADS)
Ganopolski, A.; Willeit, M.; Calov, R.
2017-12-01
In spite of significant progress achieved in understanding of glacial cycles, the cause of Mid-Pleistocene transition (MPT) is still not fully understood. To study possible mechanisms of the MPT we used the Earth system model of intermediate complexity CLIMBER-2 which incorporates all major components of the Earth system - atmosphere, ocean, land surface, northern hemisphere ice sheets, terrestrial biota and soil carbon, aeolian dust and marine biogeochemistry. We run the model through the entire Quaternary. The only prescribed forcing in these simulations is variations in Earth orbital parameters. In addition we prescribed gradually evolving in time terrestrial sediment cover and global volcanic outgassing. We found that gradual removal of terrestrial sediment from the Northern Hemisphere continent by glacial processes is sufficient to explain transition from 40-ka to 100-ka worlds around 1 million years ago. By starting the model at different times and using the same initial conditions we found that modeling results converge to the same solution which depends only on the orbital forcing and lower boundary conditions. Our results thus strongly suggest that Quaternary glacial cycles are externally forced and nearly deterministic.
Application of remote sensing to estimating soil erosion potential
NASA Technical Reports Server (NTRS)
Morris-Jones, D. R.; Kiefer, R. W.
1980-01-01
A variety of remote sensing data sources and interpretation techniques has been tested in a 6136 hectare watershed with agricultural, forest and urban land cover to determine the relative utility of alternative aerial photographic data sources for gathering the desired land use/land cover data. The principal photographic data sources are high altitude 9 x 9 inch color infrared photos at 1:120,000 and 1:60,000 and multi-date medium altitude color and color infrared photos at 1:60,000. Principal data for estimating soil erosion potential include precipitation, soil, slope, crop, crop practice, and land use/land cover data derived from topographic maps, soil maps, and remote sensing. A computer-based geographic information system organized on a one-hectare grid cell basis is used to store and quantify the information collected using different data sources and interpretation techniques. Research results are compared with traditional Universal Soil Loss Equation field survey methods.
The National Land Cover Data (NLCD) is a land cover classification derived from Landsat Thematic Mapper satellite data collected in the early to mid-1990s. In this work, land use coverages calculated from the NLCD database are used to assess the impact of non-point sources on the...
Ross, Beth E.; Haukos, David A.; Hagen, Christian A.; Pitman, James C.
2016-01-01
Habitat loss and degradation compound the effects of climate change on wildlife, yet responses to climate and land cover change are often quantified independently. The interaction between climate and land cover change could be intensified in the Great Plains region where grasslands are being converted to row-crop agriculture concurrent with increased frequency of extreme drought events. We quantified the combined effects of land cover and climate change on a species of conservation concern in the Great Plains, the Lesser Prairie-Chicken (Tympanuchus pallidicinctus ). We combined extreme drought events and land cover change with lek count surveys in a Bayesian hierarchical model to quantify changes in abundance of male Lesser Prairie-Chickens from 1978 to 2014 in Kansas, the core of their species range. Our estimates of abundance indicate a gradually decreasing population through 2010 corresponding to drought events and reduced grassland areas. Decreases in Lesser Prairie-Chicken abundance were greatest in areas with increasing row-crop to grassland land cover ratio during extreme drought events, and decreased grassland reduces the resilience of Lesser Prairie-Chicken populations to extreme drought events. A threshold exists for Lesser Prairie-Chickens in response to the gradient of cropland:grassland land cover. When moving across the gradient of grassland to cropland, abundance initially increased in response to more cropland on the landscape, but declined in response to more cropland after the threshold (δ=0.096, or 9.6% cropland). Preservation of intact grasslands and continued implementation of initiatives to revert cropland to grassland should increase Lesser Prairie-Chicken resilience to extreme drought events due to climate change.
Rheometric properties of canine vocal fold tissues: Variation with anatomic location
Kimura, Miwako; Mau, Ted; Chan, Roger W.
2010-01-01
Objective To evaluate the in vitro rheometric properties of the canine vocal fold lamina propria and muscle at phonatory frequencies, and their changes with anatomic location. Methods Six canine larynges were harvested immediately postmortem. Viscoelastic shear properties of anterior, middle, and posterior portions of the vocal fold cover (lamina propria) as well as those of the medial thyroarytenoid (TA) muscle (vocalis muscle) were quantified by a linear, controlled-strain simple-shear rheometer. Measurements of elastic shear modulus (G’) and dynamic viscosity (η’) of the specimens were conducted with small-amplitude sinusoidal shear deformation over a frequency range of 1 Hz to 250 Hz. Results All specimens showed similar frequency dependence of the viscoelastic functions, with G’ gradually increasing with frequency and η’ decreasing with frequency monotonically. G’ and η’ of the canine vocalis muscle were significantly higher than those of the canine vocal fold cover, and η’ of the canine vocal fold cover was significantly higher than that of the human vocal fold cover. There were no significant differences in G’ and in η’ between different portions of the canine vocal fold cover. Conclusion These preliminary data based on the canine model suggested that the vocalis muscle, while in a relaxed state in vitro, is significantly stiffer and more viscous than the vocal fold cover during vibration at phonatory frequencies. For large-amplitude vocal fold vibration involving the medial portion of the TA muscle, such distinct differences in viscoelastic properties of different layers of the vocal fold should be taken into account in multi-layered biomechanical models of phonation. PMID:21035291
The bright thread: the Bulletin's 75th anniversary.
Beatty, W K
1986-01-01
This chronological review of the Bulletin of the Medical Library Association deals with the years 1911 through 1985. The Bulletin has had nineteen editors, from Marcia C. Noyes and John Ruhräh, M.D. (1911-26), through Susan Crawford, Ph.D. (1983-1986). This paper describes the Bulletin's gradual expansion in size and contents, the initiation of various departments and sections, and some of the pioneering articles. Major steps in expenses, income, and subscription price are given. Important changes in the format and the growth of the administrative and advisory structures are covered. Images PMID:3527309
The bright thread: the Bulletin's 75th anniversary.
Beatty, W K
1998-01-01
This chronological review of the Bulletin of the Medical Library Association deals with the years 1911 through 1985. The Bulletin has had nineteen editors, from Marcia C. Noyes and John Ruhräh, M.D. (1911-26), through Susan Crawford, Ph.D. (1983-1986). This paper describes the Bulletin's gradual expansion in size and contents, the initiation of various departments and sections, and some of the pioneering articles. Major steps in expenses, income, and subscription price are given. Important changes in the format and the growth of the administrative and advisory structures are covered. Images PMID:9578946
NASA Astrophysics Data System (ADS)
Sprigg, W. A.; Sahoo, S.; Prasad, A. K.; Venkatesh, A. S.; Vukovic, A.; Nickovic, S.
2015-12-01
Identification and evaluation of sources of aeolian mineral dust is a critical task in the simulation of dust. Recently, time series of space based multi-sensor satellite images have been used to identify and monitor changes in the land surface characteristics. Modeling of windblown dust requires precise delineation of mineral dust source and its strength that varies over a region as well as seasonal and inter-annual variability due to changes in land use and land cover. Southwest USA is one of the major dust emission prone zone in North American continent where dust is generated from low lying dried-up areas with bare ground surface and they may be scattered or appear as point sources on high resolution satellite images. In the current research, various satellite derived variables have been integrated to produce a high-resolution dust source mask, at grid size of 250 m, using data such as digital elevation model, surface reflectance, vegetation cover, land cover class, and surface wetness. Previous dust source models have been adopted to produce a multi-parameter dust source mask using data from satellites such as Terra (Moderate Resolution Imaging Spectroradiometer - MODIS), and Landsat. The dust source mask model captures the topographically low regions with bare soil surface, dried-up river plains, and lakes which form important source of dust in southwest USA. The study region is also one of the hottest regions of USA where surface dryness, land use (agricultural use), and vegetation cover changes significantly leading to major changes in the areal coverage of potential dust source regions. A dynamic high resolution dust source mask have been produced to address intra-annual change in the aerial extent of bare dry surfaces. Time series of satellite derived data have been used to create dynamic dust source masks. A new dust source mask at 16 day interval allows enhanced detection of potential dust source regions that can be employed in the dust emission and transport pathways models for better estimation of emission of dust during dust storms, particulate air pollution, public health risk assessment tools and decision support systems.
Open-tube diffusion techniques for InP/LnGaAs heterojunctior bipolar transistors
NASA Astrophysics Data System (ADS)
Schuitemaker, P.; Houston, P. A.
1986-11-01
Open-tube diffusion techniques used between 450 and 600° C are described which involve the supply of diffusant from a vapour source (via a solution) and a solid evaporated metal source. Investigations of Zn into InP and InGaAs(P) have been undertaken using both sources. SIMS profile analyses show that in the case of the vapour source the profiles indicate a concentration-dependent diffusion coefficient while the solid source diffusions can be well described by a Gaussian-type profile. The usefulness of the vapour source method has been demonstrated in the fabrication of bipolar transistors which exhibit good d.c. characteristics. The solid source method is limited by the slow diffusion velocity and more gradual profile. The InGaAs(P)/InP materials system has important applications in optical communications and future high speed microwave and switching devices. Useful technologies allied to the introduction of impurities into Si by diffusion, have gradually been emerging for use in the III-V semiconductor family. Closed tube systems1 have been used in order to contain the volatile group V species and prevent surface erosion. In addition, simpler open tube systems2,3 have been developed that maintain a sufficient overpressure of the group V element. Zn and Cd p-dopants have been studied extensively because of the volatility and relatively large diffusion rates in III-V semiconductors. Opentube diffusion into both InP and InGaAs2-6 has been studied but little detail has appeared concerning InGaAs and InGaAsP. In this paper we describe a comprehensive study of the diffusion of Zn into InP and InGaAs(P) using both open-tube vapour source and a Au/Zn/Au evaporated solid source with SiNx acting both as a mask and also an encapsulant to prevent loss of Zn and decomposition of the substrate material. The techniques have been successfully applied to the fabrication of InP/lnGaAs heterojunction bipolar transistors which show good dc characteristics. Reference to InGaAs in the text implies the InP lattice-matched composition In0.53Ga0.47As.
Wesolowski, Edwin A.
1996-01-01
Two separate studies to simulate the effects of discharging treated wastewater to the Red River of the North at Fargo, North Dakota, and Moorhead, Minnesota, have been completed. In the first study, the Red River at Fargo Water-Quality Model was calibrated and verified for icefree conditions. In the second study, the Red River at Fargo Ice-Cover Water-Quality Model was verified for ice-cover conditions.To better understand and apply the Red River at Fargo Water-Quality Model and the Red River at Fargo Ice-Cover Water-Quality Model, the uncertainty associated with simulated constituent concentrations and property values was analyzed and quantified using the Enhanced Stream Water Quality Model-Uncertainty Analysis. The Monte Carlo simulation and first-order error analysis methods were used to analyze the uncertainty in simulated values for six constituents and properties at sites 5, 10, and 14 (upstream to downstream order). The constituents and properties analyzed for uncertainty are specific conductance, total organic nitrogen (reported as nitrogen), total ammonia (reported as nitrogen), total nitrite plus nitrate (reported as nitrogen), 5-day carbonaceous biochemical oxygen demand for ice-cover conditions and ultimate carbonaceous biochemical oxygen demand for ice-free conditions, and dissolved oxygen. Results are given in detail for both the ice-cover and ice-free conditions for specific conductance, total ammonia, and dissolved oxygen.The sensitivity and uncertainty of the simulated constituent concentrations and property values to input variables differ substantially between ice-cover and ice-free conditions. During ice-cover conditions, simulated specific-conductance values are most sensitive to the headwatersource specific-conductance values upstream of site 10 and the point-source specific-conductance values downstream of site 10. These headwater-source and point-source specific-conductance values also are the key sources of uncertainty. Simulated total ammonia concentrations are most sensitive to the point-source total ammonia concentrations at all three sites. Other input variables that contribute substantially to the variability of simulated total ammonia concentrations are the headwater-source total ammonia and the instream reaction coefficient for biological decay of total ammonia to total nitrite. Simulated dissolved-oxygen concentrations at all three sites are most sensitive to headwater-source dissolved-oxygen concentration. This input variable is the key source of variability for simulated dissolved-oxygen concentrations at sites 5 and 10. Headwatersource and point-source dissolved-oxygen concentrations are the key sources of variability for simulated dissolved-oxygen concentrations at site 14.During ice-free conditions, simulated specific-conductance values at all three sites are most sensitive to the headwater-source specific-conductance values. Headwater-source specificconductance values also are the key source of uncertainty. The input variables to which total ammonia and dissolved oxygen are most sensitive vary from site to site and may or may not correspond to the input variables that contribute the most to the variability. The input variables that contribute the most to the variability of simulated total ammonia concentrations are pointsource total ammonia, instream reaction coefficient for biological decay of total ammonia to total nitrite, and Manning's roughness coefficient. The input variables that contribute the most to the variability of simulated dissolved-oxygen concentrations are reaeration rate, sediment oxygen demand rate, and headwater-source algae as chlorophyll a.
Skills Conversion Project: Chapter 19, Profile of the Technological Manpower Pool. Final Report.
ERIC Educational Resources Information Center
National Society of Professional Engineers, Washington, DC.
In the absence of any one central source of data covering the profile of the unemployed aerospace and defense technical professional, an extensive analysis of multiple data sources was conducted for the U.S. Department of Labor by the National Society for Professional Engineers. The survey and analysis included data covering approximately 63,000…
Sediment delivery to the Gulf of Alaska: source mechanisms along a glaciated transform margin
Dobson, M.R.; O'Leary, D.; Veart, M.
1998-01-01
Sediment delivery to the Gulf of Alaska occurs via four areally extensive deep-water fans, sourced from grounded tidewater glaciers. During periods of climatic cooling, glaciers cross a narrow shelf and discharge sediment down the continental slope. Because the coastal terrain is dominated by fjords and a narrow, high-relief Pacific watershed, deposition is dominated by channellized point-source fan accumulations, the volumes of which are primarily a function of climate. The sediment distribution is modified by a long-term tectonic translation of the Pacific plate to the north along the transform margin. As a result, the deep-water fans are gradually moved away from the climatically controlled point sources. Sets of abandoned channels record the effect of translation during the Plio-Pleistocene.
NASA Astrophysics Data System (ADS)
Ricaurte-Villota, Constanza; Gonzalez-Yajimovich, Oscar; Betancourt-Portela, Julian
2014-05-01
This study used biomarkers such as n-alkanes, especially focused on the long chain n-alkanes and some diagnostic indexes derived from abundance, to elucidate molecular changes in the contribution of organic matter to the sediments, especially terrestrial vegetation surrounding continental areas around of Alfonso basin in response to climate change, particularly changes in the hydrological cycle. The results show that in general the n-alkanes of organic matter (OM) of Alfonso basin sediments are composed of a mixture of waxes derived from phytoplankton and terrestrial plants, with a greater contribution from phytoplankton compare to terrestrial vegetation, in the oldest part of the record, associated with a marine productivity increased period favored by rainfall. Maximum abundance of C29, and high values of C27/C31 ratio indicate leaves from trees as a source wax, probably succulents plants characteristic of arid zones, with C3 as one of their metabolic pathway, identified from mean ACL values around 29.5. The low CPI index indicates contamination and microbial communities as a possible source of long chain n-alkanes, probably due to anoxic bottom conditions in Alfonso basin favor the development of these communities. Finally, it is suggested no change in the community, at least for the last ~ 3.5 ka BP, but increased cover vegetation (biomass) in southern California during periods of increased rainfall (from ~ 3.5 to ~ 1.7 ka BP). The ability of terrestrial plant communities to adapt for longer periods before being replaced by other species, when faced with gradual changes rather than rapid climate change is reflected in a few changes in its composition.
Kookana, Rai S.; Williams, Mike; Boxall, Alistair B. A.; Larsson, D. G. Joakim; Gaw, Sally; Choi, Kyungho; Yamamoto, Hiroshi; Thatikonda, Shashidhar; Zhu, Yong-Guan; Carriquiriborde, Pedro
2014-01-01
Active pharmaceutical ingredients (APIs) can enter the natural environment during manufacture, use and/or disposal, and consequently public concern about their potential adverse impacts in the environment is growing. Despite the bulk of the human population living in Asia and Africa (mostly in low- or middle-income countries), limited work relating to research, development and regulations on APIs in the environment have so far been conducted in these regions. Also, the API manufacturing sector is gradually shifting to countries with lower production costs. This paper focuses mainly on APIs for human consumption and highlights key differences between the low-, middle- and high-income countries, covering factors such as population and demographics, manufacture, prescriptions, treatment, disposal and reuse of waste and wastewater. The striking differences in populations (both human and animal), urbanization, sewer connectivity and other factors have revealed that the environmental compartments receiving the bulk of API residues differ markedly between low- and high-income countries. High sewer connectivity in developed countries allows capture and treatment of the waste stream (point-source). However, in many low- or middle-income countries, sewerage connectivity is generally low and in some areas waste is collected predominantly in septic systems. Consequently, the diffuse-source impact, such as on groundwater from leaking septic systems or on land due to disposal of raw sewage or septage, may be of greater concern. A screening level assessment of potential burdens of APIs in urban and rural environments of countries representing low- and middle-income as well as high-income has been made. Implications for ecological risks of APIs used by humans in lower income countries are discussed. PMID:25405973
Brain responses to tonal changes in the first two years of life
Jing, Hongkui; Benasich, April A.
2007-01-01
Maturation of auditory perceptual and discrimination process within the first two years of life is investigated in healthy infants by examining event-related potentials (ERPs). High-density EEG signals were recorded from the scalp monthly between 3 and 24 months of age. Two types of stimuli (100 vs. 100 Hz for standard stimuli; 100 vs. 300 Hz for deviant stimuli; occurrence rate: 85:15%) were presented using an oddball paradigm. Latencies and amplitudes were compared across development. The results showed that latencies of P150, N250, P350, and N450 components gradually decreased with increasing age. Amplitudes of the N250 and P350 components gradually increased and reached the maximum at 9 months, and then gradually decreased with the increase of age. Mismatch negativity was not obvious at 3 months of age, but was seen at 4–5 months and became robust after 6 months. Robust late positivity was recorded at all ages. These mismatch responses were noticeable in the frontal, central, and parietal areas, and the maximal MMN amplitude distribution gradually moved from the parietal area to the frontal area across the age range. Two important periods—one around 6 months and the other around 9 months are suggested in the maturation of auditory central system. Dynamical changes in the underlying source strengths and orientations may be principal contributors to ERP morphological changes in infants within the first 24 months. PMID:16373083
Source Water Quality Monitoring
Presentation will provide background information on continuous source water monitoring using online toxicity monitors and cover various tools available. Conceptual and practical aspects of source water quality monitoring will be discussed.
NASA Astrophysics Data System (ADS)
Goren, Tom; Muelmenstaedt, Johannes; Rosenfeld, Daniel; Quaas, Johannes
2017-04-01
Marine stratocumulus clouds (MSC) occur in two main cloud regimes of open and closed cells that differ significantly by their cloud cover. Closed cells gradually get cleansed of high CCN concentrations in a process that involves initiation of drizzle that breaks the full cloud cover into open cells. The drizzle creates downdrafts that organize the convection along converging gust fronts, which in turn produce stronger updrafts that can sustain more cloud water that compensates the depletion of the cloud water by the rain. In addition, having stronger updrafts allow the clouds to grow relatively deep before rain starts to deplete its cloud water. Therefore, lower droplet concentrations and stronger rain would lead to lower cloud fraction, but not necessary also to lower liquid water path (LWP). The fundamental relationships between these key variables derived from global climate model (GCM) simulations are analyzed with respect to observations in order to determine whether the GCM parameterizations can represent well the governing physical mechanisms upon MSC regime transitions. The results are used to evaluate the feasibility of GCM's for estimating aerosol cloud-mediated radiative forcing upon MSC regime transitions, which are responsible for the largest aerosol cloud-mediated radiative forcing.
NASA Astrophysics Data System (ADS)
Nguyen, Son Tung; Minkman, Ellen; Rutten, Martine
2016-04-01
Citizen science is being increasingly used in the context of environmental research, thus there are needs to evaluate cognitive ability of humans in classifying environmental features. With the focus on land cover, this study explores the extent to which citizen science can be applied in sensing and measuring the environment that contribute to the creation and validation of land cover data. The Day Basin in Vietnam was selected to be the study area. Different methods to examine humans' ability to classify land cover were implemented using different information sources: ground based photos - satellite images - field observation and investigation. Most of the participants were solicited from local people and/or volunteers. Results show that across methods and sources of information, there are similar patterns of agreement and disagreement on land cover classes among participants. Understanding these patterns is critical to create a solid basis for implementing human sensors in earth observation. Keywords: Land cover, classification, citizen science, Landsat 8
X ray photoelectron spectroscopy (XPS) analysis of Photosensitive ZrO2 array
NASA Astrophysics Data System (ADS)
Li, Y.; Zhao, G.; Zhu, R.; Kou, Z.
2018-03-01
Based on organic zirconium source as the starting material, by adding chemical modifiers which are made up with photosensitive ZrO2 sol. A uniformed ZrO2 array dot was fabricated with a mean diameter of around 800 nm. By using UV-vis spectra and X-ray photoelectron spectroscopy analysis method, studies the photosensitive ZrO2 gel film of photochemical reaction process and the photosensitive mechanism, to determine the zirconium atom centered chelate structure, reaction formed by metal chelate Zr atom for the center, and to establish the molecular model of the chelate. And studied the ultraviolet light in the process of the variation of the XPS spectra, Zr3d5/2 to 184.9 eV corresponding to the binding energy of the as the combination of state peak gradually reduce; By combining with the status of Zr-O peak gradually increase; The strength of the peak is gradually decline. This suggests that in the process of ultraviolet light photo chemical reaction happened. This study is of great significance to the micro fabrication of ZrO2 array not only to the memory devices but also to the optical devices.
Electron-Ion Intensity Dropouts in Gradual Solar Energetic Particle Events during Solar Cycle 23
NASA Astrophysics Data System (ADS)
Tan, Lun C.
2017-09-01
Since the field-line mixing model of Giacalone et al. suggests that ion dropouts cannot happen in the “gradual” solar energetic particle (SEP) event because of the large size of the particle source region in the event, the observational evidence of ion dropouts in the gradual SEP event should challenge the model. We have searched for the presence of ion dropouts in the gradual SEP event during solar cycle 23. From 10 SEP events the synchronized occurrence of ion and electron dropouts is identified in 12 periods. Our main observational facts, including the mean width of electron-ion dropout periods being consistent with the solar wind correlation scale, during the dropout period the dominance of the slab turbulence component and the enhanced turbulence power parallel to the mean magnetic field, and the ion gyroradius dependence of the edge steepness in dropout periods, are all in support of the solar wind turbulence origin of dropout events. Also, our observation indicates that a wide longitude distribution of SEP events could be due to the increase of slab turbulence fraction with the increased longitude distance from the flare-associated active region.
Remote sensing as a source of land cover information utilized in the universal soil loss equation
NASA Technical Reports Server (NTRS)
Morris-Jones, D. R.; Morgan, K. M.; Kiefer, R. W.; Scarpace, F. L.
1979-01-01
In this study, methods for gathering the land use/land cover information required by the USLE were investigated with medium altitude, multi-date color and color infrared 70-mm positive transparencies using human and computer-based interpretation techniques. Successful results, which compare favorably with traditional field study methods, were obtained within the test site watershed with airphoto data sources and human airphoto interpretation techniques. Computer-based interpretation techniques were not capable of identifying soil conservation practices but were successful to varying degrees in gathering other types of desired land use/land cover information.
Estimating the extent of impervious surfaces and turf grass across large regions
Claggett, Peter; Irani, Frederick M.; Thompson, Renee L.
2013-01-01
The ability of researchers to accurately assess the extent of impervious and pervious developed surfaces, e.g., turf grass, using land-cover data derived from Landsat satellite imagery in the Chesapeake Bay watershed is limited due to the resolution of the data and systematic discrepancies between developed land-cover classes, surface mines, forests, and farmlands. Estimates of impervious surface and turf grass area in the Mid-Atlantic, United States that were based on 2006 Landsat-derived land-cover data were substantially lower than estimates based on more authoritative and independent sources. New estimates of impervious surfaces and turf grass area derived using land-cover data combined with ancillary information on roads, housing units, surface mines, and sampled estimates of road width and residential impervious area were up to 57 and 45% higher than estimates based strictly on land-cover data. These new estimates closely approximate estimates derived from authoritative and independent sources in developed counties.
NASA Astrophysics Data System (ADS)
Huang, Y.; Engdahl, N.
2017-12-01
Proactive management to improve water resource sustainability is often limited by a lack of understanding about the hydrological consequences of human activities and climate induced land use and land cover (LULC) change. Changes in LULC can alter runoff, soil moisture, and evapotranspiration, but these effects are complex and traditional modeling techniques have had limited successes in realistically simulating the relevant feedbacks. Recent studies have investigated the coupled interactions but typically do so at coarse resolutions with simple topographic settings, so it is unclear if the previous conclusions remain valid in the steep, complex terrains that dominate the western USA. This knowledge gap was explored with a series of integrated hydrologic simulations based on the Dry Creek Experimental Watershed (DCEW) in southwestern Idaho, USA, using the ParFlow.CLM model. The DCEW has extensive monitoring data that allowed for a direct calibration and validation of the base-case simulation, which is not commonly done with integrated models. The effects of LULC change on the hydrologic and water budgets were then assessed at two grid resolutions (20m and 40m) under four LULC scenarios: 1) current LULC; 2) LULC change from a small but gradual decrease in potential recharge (PR); 3) LULC change from a large but rapid decrease in PR; and 4) LULC change from a large but gradual decrease in PR. The results show that the methods used for terrain processing and the grid resolution can both heavily impact the simulation results and that LULC change can significantly alter the relative amounts of groundwater storage and runoff.
Environmental state and tendencies of the Puerto Morelos CARICOMP site, Mexico.
Rodríguez-Martínez, Rosa E; Ruíz-Rentería, Francisco; van Tussenbroek, Brigitta; Barba-Santos, Guadalupe; Escalante-Mancera, Edgar; Jordán-Garza, Guillermo; Jordán-Dahlgren, Eric
2010-10-01
The CARICOMP site at Puerto Morelos, Mexico was monitored from 1993 to 2005. No significant changes in air temperature, wind patterns, periodicity and quantity of rainfall, sea-surface temperature and water transparency were observed between sampling years. During the study four hurricane impacts were registered. At the coral reef site overall mean cover of fleshy algae (47%) and turf algae (36%) were high, whereas cover of corals (2%) and sponges (3%), and abundance of sea-urchins (0.04 org m(-2)) were consistently low. Gorgonians were dominant and showed changes in their community structure; the number of species increased from 1993 to 1995, their abundance decreased after Hurricane Roxanne (1995) and recovered by 2001. At four seagrass sites total community biomass remained constant (707.1-929.6 g dry m(-2)) but the above-ground biomass of the seagrass Syringodium filiforme and fleshy algae increased gradually. Total biomass (531-699 g dry m(-2)) and leaf productivity (0.89-1.56 g dry m(-2) d(-1)) of the seagrass Thalassia testudinum remained constant, but the species invested proportionally more biomass in above-ground leaf tissues at the end of the study. The minor hurricanes from 1993 until 2005 had no detectable impacts on the seagrass beds, however, the major Hurricane Wilma (October 2005) changed the community composition at three stations and caused complete burial of the vegetation at a coastal station. The gradual changes in the seagrass and reef communities recorded in the 12 years of continuous monitoring of the CARICOMP site may reflect the increased pollution caused by the rapid augment in urban and tourist developments along the coasts and inland from Puerto Morelos, coupled with poor water management practices.
Source water monitoring and biomonitoring systems
Presentation will provide background information on continuous source water monitoring using online toxicity monitors and cover various tools available. Conceptual and practical aspects of source water quality monitoring will be discussed.
A Heuristic Model of Media Conflict Systems in the Wake of Expose of Cover-Ups.
ERIC Educational Resources Information Center
Nager, Norman R.
The purpose of this study was to stimulate scholarly investigation of a conflict systems model for news media and the interaction of sources in the wake of an expose. A search of the literature led to nine tentative axioms that focus attention on systemic conflict of media and sources related to cover-ups and suggested additional theory…
Development of a 20 mA negative hydrogen ion source for cyclotrons
NASA Astrophysics Data System (ADS)
Etoh, H.; Onai, M.; Arakawa, Y.; Aoki, Y.; Mitsubori, H.; Sakuraba, J.; Kato, T.; Mitsumoto, T.; Yajima, S.; Hatayama, A.; Okumura, Y.
2017-08-01
A cesiated DC negative ion source has been developed for proton cyclotrons in medical applications. A continuous H- beam of 23 mA was stably extracted at an arc power of 3 kW. The beam current gradually decreases with a constant arc power and without additional Cs injection and the decay rate was about 0.03 mA (0.14%) per hour. A feed-back control system that automatically adjusts the arc power to stabilize the beam current is able to keep the beam current constant at ±0.04 mA (±0.2%).
The global carbon dioxide budget
Sundquist, E.T.
1993-01-01
The increase in atmospheric CO2 levels during the last deglaciation was comparable in magnitude to the recent historical increase. However, global CO2 budgets for these changes reflect fundamental differences in rates and in sources and sinks. The modern oceans are a rapid net CO2 sink, whereas the oceans were a gradual source during the deglaciation. Unidentified terrestrial CO2 sinks are important uncertainties in both the deglacial and recent CO2 budgets. The deglacial CO2 budget represents a complexity of long-term dynamic behavior that is not adequately addressed by current models used to forecast future atmospheric CO2 levels.
Multicriteria analysis for sources of renewable energy using data from remote sensing
NASA Astrophysics Data System (ADS)
Matejicek, L.
2015-04-01
Renewable energy sources are major components of the strategy to reduce harmful emissions and to replace depleting fossil energy resources. Data from remote sensing can provide information for multicriteria analysis for sources of renewable energy. Advanced land cover quantification makes it possible to search for suitable sites. Multicriteria analysis, together with other data, is used to determine the energy potential and socially acceptability of suggested locations. The described case study is focused on an area of surface coal mines in the northwestern region of the Czech Republic, where the impacts of surface mining and reclamation constitute a dominant force in land cover changes. High resolution satellite images represent the main input datasets for identification of suitable sites. Solar mapping, wind predictions, the location of weirs in watersheds, road maps and demographic information complement the data from remote sensing for multicriteria analysis, which is implemented in a geographic information system (GIS). The input spatial datasets for multicriteria analysis in GIS are reclassified to a common scale and processed with raster algebra tools to identify suitable sites for sources of renewable energy. The selection of suitable sites is limited by the CORINE land cover database to mining and agricultural areas. The case study is focused on long term land cover changes in the 1985-2015 period. Multicriteria analysis based on CORINE data shows moderate changes in mapping of suitable sites for utilization of selected sources of renewable energy in 1990, 2000, 2006 and 2012. The results represent map layers showing the energy potential on a scale of a few preference classes (1-7), where the first class is linked to minimum preference and the last class to maximum preference. The attached histograms show the moderate variability of preference classes due to land cover changes caused by mining activities. The results also show a slight increase in the more preferred classes for utilization of sources of renewable energy due to an increase area of reclaimed sites. Using data from remote sensing, such as the multispectral images and the CORINE land cover datasets, can reduce the financial resources currently required for finding and assessing suitable areas.
Modeling of Passive Forces of Machine Tool Covers
NASA Astrophysics Data System (ADS)
Kolar, Petr; Hudec, Jan; Sulitka, Matej
The passive forces acting against the drive force are phenomena that influence dynamical properties and precision of linear axes equipped with feed drives. Covers are one of important sources of passive forces in machine tools. The paper describes virtual evaluation of cover passive forces using the cover complex model. The model is able to compute interaction between flexible cover segments and sealing wiper. The result is deformation of cover segments and wipers which is used together with measured friction coefficient for computation of cover total passive force. This resulting passive force is dependent on cover position. Comparison of computational results and measurement on the real cover is presented in the paper.
Goodarzi, Fariborz; Sanei, Hamed; Labonté, Marcel; Duncan, William F
2002-06-01
The spatial distribution and deposition of lead and zinc emitted from the Trail smelter, British Columbia, Canada, was studied by strategically locating moss bags in the area surrounding the smelter and monitoring the deposition of elements every three months. A combined diffusion/distribution model was applied to estimate the relative contribution of stack-emitted material and material emitted from the secondary sources (e.g., wind-blown dust from ore/slag storage piles, uncovered transportation/trucking of ore, and historical dust). The results indicate that secondary sources are the major contributor of lead and zinc deposited within a short distance from the smelter. Gradually, the stack emissions become the main source of Pb and Zn at greater distances from the smelter. Typical material originating from each source was characterized by SEM/EDX, which indicated a marked difference in their morphology and chemical composition.
Determining the torus covering factors for a sample of type 1 AGN in the local Universe
NASA Astrophysics Data System (ADS)
Ezhikode, Savithri H.; Gandhi, Poshak; Done, Chris; Ward, Martin; Dewangan, Gulab C.; Misra, Ranjeev; Philip, Ninan Sajeeth
2017-12-01
In the unified scheme of active galactic nuclei, a dusty torus absorbs and then reprocesses a fraction of the intrinsic luminosity which is emitted at longer wavelengths. Thus, subject to radiative transfer corrections, the fraction of the sky covered by the torus as seen from the central source (known as the covering factor fc) can be estimated from the ratio of the infrared to the bolometric luminosities of the source as fc = Ltorus/LBol. However, the uncertainty in determining LBol has made the estimation of covering factors by this technique difficult, especially for AGN in the local Universe where the peak of the observed spectral energy distributions lies in the UV (ultraviolet). Here, we determine the covering factors of an X-ray/optically selected sample of 51 type 1 AGN. The bolometric luminosities of these sources are derived using a self-consistent, energy-conserving model that estimates the contribution in the unobservable far-UV region, using multifrequency data obtained from SDSS, XMM-Newton, WISE, 2MASS and UKIDSS. We derive a mean value of fc ∼ 0.30 with a dispersion of 0.17. Sample correlations, combined with simulations, show that fc is more strongly anticorrelated with λEdd than with LBol. This points to large-scale torus geometry changes associated with the Eddington-dependent accretion flow, rather than a receding torus, with its inner sublimation radius determined solely by heating from the central source. Furthermore, we do not see any significant change in the distribution of fc for sub-samples of radio-loud sources or Narrow Line Seyfert 1 galaxies (NLS1s), though these sub-samples are small.
Long-term dynamics of a high-latitude coral reef community at Sodwana Bay, South Africa
NASA Astrophysics Data System (ADS)
Porter, S. N.; Schleyer, M. H.
2017-06-01
Dynamics in reef cover, mortality and recruitment success of a high-latitude coral community in South Africa were studied over 20 yr with the aim to detect the effects of climate change. Coral communities at this locality are the southernmost on the African continent, non-accretive, attain high biodiversity and are dominated by soft corals. Long-term monitoring within fixed transects on representative reef was initiated in 1993 and has entailed annual photo-quadrat surveys and hourly temperature logging. Although sea temperatures rose by 0.15 °C p.a. at the site up to 2000, they have subsequently been decreasing, and the overall trend based on monthly means has been a significant decrease of 0.03 °C p.a. Despite this, minor bleaching was encountered in the region during the 1998 El Niño-Southern Oscillation event, again in the summer of 2000/2001 and in 2005. A significant decreasing trend of 0.95% p.a. in soft coral cover has been evident throughout the monitoring period, attributable to significant decreases in Sinularia and Lobophytum spp. cover. In contrast, hard coral cover gradually and significantly increased up to 2005, this being largely attributable to increases in cover by Acropora spp. Recruitment success and mortality of both soft and hard corals has displayed high inter-annual variability with increasing but non-significant trends in the last 5 yr. The reduction in soft coral cover has been more consistent and greater than that of hard corals, but it is difficult at this stage to attribute this to changes in water quality, acidification-linked accretion or temperature.
40 CFR 63.8682 - What parts of my plant does this subpart cover?
Code of Federal Regulations, 2010 CFR
2010-07-01
... CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Asphalt Processing and Asphalt Roofing Manufacturing What This Subpart Covers § 63.8682 What parts of my plant does this subpart cover? (a) This subpart applies to each new, reconstructed, or existing affected source at asphalt...
40 CFR 63.8682 - What parts of my plant does this subpart cover?
Code of Federal Regulations, 2014 CFR
2014-07-01
... CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Asphalt Processing and Asphalt Roofing Manufacturing What This Subpart Covers § 63.8682 What parts of my plant does this subpart cover? (a) This subpart applies to each new, reconstructed, or existing affected source at asphalt...
40 CFR 63.8682 - What parts of my plant does this subpart cover?
Code of Federal Regulations, 2011 CFR
2011-07-01
... CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Asphalt Processing and Asphalt Roofing Manufacturing What This Subpart Covers § 63.8682 What parts of my plant does this subpart cover? (a) This subpart applies to each new, reconstructed, or existing affected source at asphalt...
40 CFR 63.8682 - What parts of my plant does this subpart cover?
Code of Federal Regulations, 2013 CFR
2013-07-01
... CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Asphalt Processing and Asphalt Roofing Manufacturing What This Subpart Covers § 63.8682 What parts of my plant does this subpart cover? (a) This subpart applies to each new, reconstructed, or existing affected source at asphalt...
40 CFR 63.8682 - What parts of my plant does this subpart cover?
Code of Federal Regulations, 2012 CFR
2012-07-01
... CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Asphalt Processing and Asphalt Roofing Manufacturing What This Subpart Covers § 63.8682 What parts of my plant does this subpart cover? (a) This subpart applies to each new, reconstructed, or existing affected source at asphalt...
Cellulosic Biofuel Production with Winter Cover Crops: Yield and Nitrogen Implications
USDA-ARS?s Scientific Manuscript database
Interest in renewable energy sources derived from plant biomass is increasing. Growing cover crops after harvest of the primary crop has been proposed as a solution to producing cellulosic biomass on existing crop-producing land without reducing food-harvest potential. Growing cover crops is a recom...
Section summary: Remote sensing
Belinda Arunarwati Margono
2013-01-01
Remote sensing is an important data source for monitoring the change of forest cover, in terms of both total removal of forest cover (deforestation), and change of canopy cover, structure and forest ecosystem services that result in forest degradation. In the context of Intergovernmental Panel on Climate Change (IPCC), forest degradation monitoring requires information...
NASA Astrophysics Data System (ADS)
Isobe, H.; Torii, M.
2016-12-01
2016 Kumamoto Earthquake triggered numerous landslides in Aso caldera area, Japan and incurred heavy casualties. Landslides occurred not only on steep slopes at the caldera cliffs or the barranco but also on relatively gradual slopes at the side of the central cones in the Aso caldera. The Aso volcano is a volcanic complex with huge caldera formed by catastrophic eruption at approximately 90ka and central cones formed by subsequent activities to recent years. The central cones are volcanic peaks contain various rocks including basaltic, andesitic and rhoyolitic lavas and pyroclastic materials. In this study, we analyzed the samples collected from the bottom surface of landslides occurred at the gradual hillside on the western flank of the Aso central cones. The subsurface geology of the site is Takanoobane rhyolite lava, 51ka, covered by dark silty or pelitic tuffs and black soil strata including Kusasenri pumice layer, 31ka. The bottom plane of the landslides can be seen as flat surfaces at boundaries between units in the Kusasenri pumice or bottom of the Kusasenri pumice on the pelitic tuff with charcoaled plants. The Kusasenri pumice layer is a coarse grained and highly permeable but poorly continuous. X-ray diffraction analysis revealed that the main component of the samples is halloysite (10Å). Halloysite (10Å) is alteration product of fine grained volcanic ash, and swellable clay with interlayer water molecules which bring sticky and deformable characteristics. The landslides caused by 2016 Kumamoto Earthquake occurred without precipitation within a week. Strong earthquake may fluidize swellable clay layers in gradual slopes and triggered heavy landslides.
NASA Astrophysics Data System (ADS)
Li, Jun; Qin, Qiming; Xie, Chao; Zhao, Yue
2012-10-01
The update frequency of digital road maps influences the quality of road-dependent services. However, digital road maps surveyed by probe vehicles or extracted from remotely sensed images still have a long updating circle and their cost remain high. With GPS technology and wireless communication technology maturing and their cost decreasing, floating car technology has been used in traffic monitoring and management, and the dynamic positioning data from floating cars become a new data source for updating road maps. In this paper, we aim to update digital road maps using the floating car data from China's National Commercial Vehicle Monitoring Platform, and present an incremental road network extraction method suitable for the platform's GPS data whose sampling frequency is low and which cover a large area. Based on both spatial and semantic relationships between a trajectory point and its associated road segment, the method classifies each trajectory point, and then merges every trajectory point into the candidate road network through the adding or modifying process according to its type. The road network is gradually updated until all trajectories have been processed. Finally, this method is applied in the updating process of major roads in North China and the experimental results reveal that it can accurately derive geometric information of roads under various scenes. This paper provides a highly-efficient, low-cost approach to update digital road maps.
Cancer incidence rates in the Kurdistan region/Iraq from 2007-2009.
Othman, Ramadhan T; Abdulljabar, Rezvan; Saeed, Abdullah; Kittani, Sarwar Sadiq; Sulaiman, Hushyar M; Mohammed, Sami A; Rashid, Rekawt M; Hussein, Nawfal R
2011-01-01
Cancer is a disease of gradual increase in incidence overall the world. Kurdistan Region in Iraq has been exposed to several carcinogenic hazards. There are few reports about the increased risk of cancer in different cities in Iraq. These reports did not cover Kurdistan region. The aim of this paper was to study cancer incidence and to identify possible risks of cancer in this region. Cancer registries from 9 hospitals in three cities of Kurdistan were used as a source of data. Information on these cases was subjected to careful verification regarding repetition, place of residence and other possible errors. Overall registered cases in 2007, 2008 and 2009 were 1444, 2081, 2356 respectively. 49% of registered cases were males and 51% were female. The Age Standardized Rate of cancer was 89.83/100 000 among male and 83.93/100 000 among female. The results showed major variation in incidence rates of different types of cancer in the three governorates of Kurdistan. Furthermore, there was evidence of increased risks of cancer in Kurdistan Region in Iraq. Hematological malignancies were the most common cancer among male (21.13% of all cancer in males) and second most common in female (18.8% of all cancer in female), only exceeded by breast cancer. To reach sound conclusions about extent and determinants of cancer in Kurdistan, enormous multi-spectrum efforts are now needed.
Early-warning signals for catastrophic soil degradation
NASA Astrophysics Data System (ADS)
Karssenberg, Derek
2010-05-01
Many earth systems have critical thresholds at which the system shifts abruptly from one state to another. Such critical transitions have been described, among others, for climate, vegetation, animal populations, and geomorphology. Predicting the timing of critical transitions before they are reached is of importance because of the large impact on nature and society associated with the transition. However, it is notably difficult to predict the timing of a transition. This is because the state variables of the system show little change before the threshold is reached. As a result, the precision of field observations is often too low to provide predictions of the timing of a transition. A possible solution is the use of spatio-temporal patterns in state variables as leading indicators of a transition. It is becoming clear that the critically slowing down of a system causes spatio-temporal autocorrelation and variance to increase before the transition. Thus, spatio-temporal patterns are important candidates for early-warning signals. In this research we will show that these early-warning signals also exist in geomorphological systems. We consider a modelled vegetation-soil system under a gradually increasing grazing pressure causing an abrupt shift towards extensive soil degradation. It is shown that changes in spatio-temporal patterns occur well ahead of this catastrophic transition. A distributed model describing the coupled processes of vegetation growth and geomorphological denudation is adapted. The model uses well-studied simple process representations for vegetation and geomorphology. A logistic growth model calculates vegetation cover as a function of grazing pressure and vegetation growth rate. Evolution of the soil thickness is modelled by soil creep and wash processes, as a function of net rain reaching the surface. The vegetation and soil system are coupled by 1) decreasing vegetation growth with decreasing soil thickness and 2) increasing soil wash with decreasing vegetation cover. The model describes a critical, catastrophic transition of an underexploited system with low grazing pressure towards an overexploited system. The underexploited state has high vegetation cover and well developed soils, while the overexploited state has low vegetation cover and largely degraded soils. We first show why spatio-temporal patterns in vegetation cover, morphology, erosion rate, and sediment load should be expected to change well before the critical transition towards the overexploited state. Subsequently, spatio-temporal patterns are quantified by calculating statistics, in particular first order statistics and autocorrelation in space and time. It is shown that these statistics gradually change before the transition is reached. This indicates that the statistics may serve as early-warning signals in real-world applications. We also discuss the potential use of remote sensing to predict the critical transition in real-world landscapes.
Mapping erodibility in dust source regions based on geomorphology, meteorology, and remote sensing
NASA Astrophysics Data System (ADS)
Parajuli, Sagar Prasad; Yang, Zong-Liang; Kocurek, Gary
2014-09-01
Mineral dust in the atmosphere has implications for Earth's radiation budget, biogeochemical cycles, hydrological cycles, human health, and visibility. Currently, the simulated vertical mass flux of dust differs greatly among the existing dust models. While most of the models utilize an erodibility factor to characterize dust sources, this factor is assumed to be static, without sufficient characterization of the highly heterogeneous and dynamic nature of dust source regions. We present a high-resolution land cover map of the Middle East and North Africa (MENA) in which the terrain is classified by visually examining satellite images obtained from Google Earth Professional and Environmental Systems Research Institute Basemap. We show that the correlation between surface wind speed and Moderate Resolution Imaging Spectroradiometer deep blue aerosol optical depth (AOD) can be used as a proxy for erodibility, which satisfactorily represents the spatiotemporal distribution of soil-derived dust sources. This method also identifies agricultural dust sources and eliminates the satellite-observed dust component that arises from long-range transport, pollution, and biomass burning. The erodible land cover of the MENA region is grouped into nine categories: (1) bedrock: with sediment, (2) sand deposit, (3) sand deposit: on bedrock, (4) sand deposit: stabilized, (5) agricultural and urban area, (6) fluvial system, (7) stony surface, (8) playa/sabkha, and (9) savanna/grassland. Our results indicate that erodibility is linked to the land cover type and has regional variation. An improved land cover map, which explicitly accounts for sediment supply, availability, and transport capacity, may be necessary to represent the highly dynamic nature of dust sources in climate models.
The development of microalgal biotechnology in the Czech Republic.
Masojídek, Jiří; Prášil, Ondřej
2010-12-01
Microscopic algae and cyanobacteria are excellent sources of numerous compounds, from raw biomass rich in proteins, oils, and antioxidants to valuable secondary metabolites with potential medical use. In the former Czechoslovakia, microalgal biotechnology developed rapidly in the 1960s with the main aim of providing industrial, high-yield sources of algal biomass. Unique cultivation techniques that are still in use were successfully developed and tested. Gradually, the focus changed from bulk production to more sophisticated use of microalgae, including production of bioactive compounds. Along the way, better understanding of the physiology and cell biology of productive microalgal strains was achieved. Currently, microalgae are in the focus again, mostly as possible sources of bioactive compounds and next-generation biofuels for the 21st century.
The noise generated by a landing gear wheel with hub and rim cavities
NASA Astrophysics Data System (ADS)
Wang, Meng; Angland, David; Zhang, Xin
2017-03-01
Wheels are one of the major noise sources of landing gears. Accurate numerical predictions of wheel noise can provide an insight into the physical mechanism of landing gear noise generation and can aid in the design of noise control devices. The major noise sources of a 33% scaled isolated landing gear wheel are investigated by simulating three different wheel configurations using high-order numerical simulations to compute the flow field and the FW-H equation to obtain the far-field acoustic pressures. The baseline configuration is a wheel with a hub cavity and two rim cavities. Two additional simulations are performed; one with the hub cavity covered (NHC) and the other with both the hub cavity and rim cavities covered (NHCRC). These simulations isolate the effects of the hub cavity and rim cavities on the overall wheel noise. The surface flow patterns are visualised by shear stress lines and show that the flow separations and attachments on the side of the wheel, in both the baseline and the configuration with only the hub cavity covered, are significantly reduced by covering both the hub and rim cavities. A frequency-domain FW-H equation is used to identify the noise source regions on the surface of the wheel. The tyre is the main low frequency noise source and shows a lift dipole and side force dipole pattern depending on the frequency. The hub cavity is identified as the dominant middle frequency noise source and radiates in a frequency range centered around the first and second depth modes of the cylindrical hub cavity. The rim cavities are the main high-frequency noise sources. With the hub cavity and rim cavities covered, the largest reduction in Overall Sound Pressure Level (OASPL) is achieved in the hub side direction. In the other directivities, there is also a reduction in the radiated sound.
Near earth tracking/data exploration
NASA Technical Reports Server (NTRS)
Spearing, Robert
1990-01-01
The future challenges facing NASA's data acquisition program are examined, with emphasis on the near-earth exploration activity and the associated data systems. It is noted that the process that is being followed is an evolutionary one: new technologies are being gradually integrated into currently operating systems. For example, advanced handling is already being introduced into such programs as the Space Telescope and the Gamma Ray Source Observatory System.
Scenarios for Russian Agricultural Development to 2021
2011-12-01
dependence on government intervention in both good times and bad, and an unwieldy, inefficient bureaucracy strained to effectively carry out the myriad...information is estimated to average 1 hour per response, including the time for reviewing instruction, searching existing data sources, gathering and...issue analysis. Emerging issue analysis begins with the premise that problems develop gradually over time , and are often ignored until they reach
ERIC Educational Resources Information Center
Yucel, Robyn; Bird, Fiona L.; Young, Jodie; Blanksby, Tania
2014-01-01
Lack of clarity about assessment criteria and standards is a source of anxiety for many first-year university students. The Developing Understanding of Assessment for Learning (DUAL) programme was designed as a staged approach to gradually familiarise students with expectations, and to provide opportunities for the development of the skills…
NASA Astrophysics Data System (ADS)
Dai, Lu; Weng, Chengyu
2015-12-01
The upper part (191-1439 cm) of the marine sediment core MD05-2906 from the northern South China Sea (SCS) was palynologically investigated. The chronology suggested that it covered the record since ~19 calendar kiloyears before present (cal ka BP) and revealed a detailed environmental change history since the late last glacial maximum (LGM). During the late LGM, due to the lowered sea level (~100 m lower) and the shortened distance from the shore to the study site, the pollen concentration was very high. The pollen assemblages were dominated by non-arboreal taxa, especially Artemisia pollen, before ~15 cal ka BP. Abundant subtropical and tropical pollen taxa were still important components and a south subtropical climate prevailed during the late LGM. The coexistent rich Artemisia pollen possibly was not derived from near shores, but was derived mainly from the northern exposed continental shelf in the East China Sea (ECS). After ~15 cal ka BP, with the rise in the sea level and enhanced distance from the pollen source areas to the core site, pollen concentrations started to decline gradually. However, during the late deglaciation and early Holocene, the higher concentrations of many pollen taxa reoccurred, which cannot be attributed to the sea level changes. Pinus pollen deposited in the core, which is considered to be mostly water-carried based on many modern pollen surveys, also started to dramatically increase at the same time. Therefore, the higher pollen concentration, with more Pinus and Typha (an aquatic plant) pollen indicated a notably enhanced terrestrial runoff and precipitation during the last deglaciation/Holocene transition (~11.3-9.4 cal ka BP). We inferred that a strong summer monsoon occurred at this time. During the late LGM/deglaciation transition period, the pollen assemblage reflected a gradually warming climate, and the climate fluctuations derived from the high-latitudes were not well-identified. This study suggests that solar insolation played a crucial role in controlling the East Asian monsoon and hydrological cycle in the northern SCS.
Bait distribution among multiple colonies of Pharaoh ants (hymenoptera: Formicidae).
Oi, D H; Vail, K M; Williams, D F
2000-08-01
Pharaoh ant, Monomorium pharaonis (L.), infestations often consist of several colonies located at different nest sites. To achieve control, it is desirable to suppress or eliminate the populations of a majority of these colonies. We compared the trophallactic distribution and efficacy of two ant baits, with different modes of action, among groups of four colonies of Pharaoh ants. Baits contained either the metabolic-inhibiting active ingredient hydramethylnon or the insect growth regulator (IGR) pyriproxyfen. Within 3 wk, the hydramethylnon bait reduced worker and brood populations by at least 80%, and queen reductions ranged between 73 and 100%, when nests were in proximity (within 132 cm) to the bait source. However, these nest sites were reoccupied by ants from other colonies located further from the bait source. The pyriproxyfen bait was distributed more thoroughly to all nest locations with worker populations gradually declining by 73% at all nest sites after 8 wk. Average queen reductions ranged from 31 to 49% for all nest sites throughout the study. Even though some queens survived, brood reductions were rapid in the pyriproxyfen treatment, with reductions of 95% at all locations by week 3. Unlike the metabolic inhibitor, the IGR did not kill adult worker ants quickly, thus, more surviving worker ants were available to distribute the bait to all colonies located at different nest sites. Thus, from a single bait source, the slow-acting bait toxicant provided gradual, but long-term control, whereas the fast-acting bait toxicant provided rapid, localized control for a shorter duration.
Climate-driven regime shifts in Arctic marine benthos
Kortsch, Susanne; Primicerio, Raul; Beuchel, Frank; Renaud, Paul E.; Rodrigues, João; Lønne, Ole Jørgen; Gulliksen, Bjørn
2012-01-01
Climate warming can trigger abrupt ecosystem changes in the Arctic. Despite the considerable interest in characterizing and understanding the ecological impact of rapid climate warming in the Arctic, few long time series exist that allow addressing these research goals. During a 30-y period (1980–2010) of gradually increasing seawater temperature and decreasing sea ice cover in Svalbard, we document rapid and extensive structural changes in the rocky-bottom communities of two Arctic fjords. The most striking component of the benthic reorganization was an abrupt fivefold increase in macroalgal cover in 1995 in Kongsfjord and an eightfold increase in 2000 in Smeerenburgfjord. Simultaneous changes in the abundance of benthic invertebrates suggest that the macroalgae played a key structuring role in these communities. The abrupt, substantial, and persistent nature of the changes observed is indicative of a climate-driven ecological regime shift. The ecological processes thought to drive the observed regime shifts are likely to promote the borealization of these Arctic marine communities in the coming years. PMID:22891319
Elzouki, A-N; Smeo, M-N; Sammud, M; Elahmer, O; Daw, M; Furarah, A; Abudher, A; Mohamed, M K
2013-07-01
A high prevalence of hepatitis B (HBV) and C virus (HCV) infections has been reported among specific patient groups in Libya; a survey was thus designed to determine the extent of the problem at the national level. A multi-stage sampling design covering all administrative areas of Libya was applied, covering > 65,000 individuals of all age groups. All subjects gave a blood sample and completed a questionnaire on demographic and risk behaviour data. The prevalence of HBV surface antigen (HBsAg) and anti-HCV were 2.2% and 1.3% respectively. The prevalence of anti-HCV increased with age, rising gradually after age 30 years, in contrast to a stable prevalence of HBsAg in all age groups 10+ years. Age-adjusted risk factors for HCV infection were previous hospitalization, surgical operations, previous blood transfusions and intravenous drug use; for HBV infection only family exposure or contact with HBV case were identified.
High-frequency monopole sound source for anechoic chamber qualification
NASA Astrophysics Data System (ADS)
Saussus, Patrick; Cunefare, Kenneth A.
2003-04-01
Anechoic chamber qualification procedures require the use of an omnidirectional monopole sound source. Required characteristics for these monopole sources are explicitly listed in ISO 3745. Building a high-frequency monopole source that meets these characteristics has proved difficult due to the size limitations imposed by small wavelengths at high frequency. A prototype design developed for use in hemianechoic chambers employs telescoping tubes, which act as an inverse horn. This same design can be used in anechoic chambers, with minor adaptations. A series of gradually decreasing brass telescoping tubes is attached to the throat of a well-insulated high-frequency compression driver. Therefore, all of the sound emitted from the driver travels through the horn and exits through an opening of approximately 2.5 mm. Directivity test data show that this design meets all of the requirements set forth by ISO 3745.
[Experimental rationale for carcinogenic risk of asbestos cement industry and its products].
Pylev, D N; Smirnova, O V; Vasil'eva, L A; Khrustalev, S A; Vezentsev, A I; Gudkova, E A; Naumova, L N
2010-01-01
During intraperitoneal administration of dispersiveness-comparable chrysotile or asbestos cement fibers to rats (20 mg thrice), mesotheliomas were found in 45.1 and 7.7% of cases respectively. Asbestos cement dust induced tumors in 2.5% of cases, which is of biological importance. Cement or freeze asbestos destruction cement dust failed to cause tumors. The latter were not detected in a control group receiving physiological saline. Asbestos cement fibers and fascicles are covered by a cement matrix. Fiber amorphization gradually occurs. In lung tissue, there may be destruction of the cement coat of fascicles and release of native chrysotile fibers that are carcinogenic.
A Review of Land-Cover Mapping Activities in Coastal Alabama and Mississippi
Smith, Kathryn E.L.; Nayegandhi, Amar; Brock, John C.
2010-01-01
INTRODUCTION Land-use and land-cover (LULC) data provide important information for environmental management. Data pertaining to land-cover and land-management activities are a common requirement for spatial analyses, such as watershed modeling, climate change, and hazard assessment. In coastal areas, land development, storms, and shoreline modification amplify the need for frequent and detailed land-cover datasets. The northern Gulf of Mexico coastal area is no exception. The impact of severe storms, increases in urban area, dramatic changes in land cover, and loss of coastal-wetland habitat all indicate a vital need for reliable and comparable land-cover data. Four main attributes define a land-cover dataset: the date/time of data collection, the spatial resolution, the type of classification, and the source data. The source data are the foundation dataset used to generate LULC classification and are typically remotely sensed data, such as aerial photography or satellite imagery. These source data have a large influence on the final LULC data product, so much so that one can classify LULC datasets into two general groups: LULC data derived from aerial photography and LULC data derived from satellite imagery. The final LULC data can be converted from one format to another (for instance, vector LULC data can be converted into raster data for analysis purposes, and vice versa), but each subsequent dataset maintains the imprint of the source medium within its spatial accuracy and data features. The source data will also influence the spatial and temporal resolution, as well as the type of classification. The intended application of the LULC data typically defines the type of source data and methodology, with satellite imagery being selected for large landscapes (state-wide, national data products) and repeatability (environmental monitoring and change analysis). The coarse spatial scale and lack of refined land-use categories are typical drawbacks to satellite-based land-use classifications. Aerial photography is typically selected for smaller landscapes (watershed-basin scale), for greater definition of the land-use categories, and for increased spatial resolution. Disadvantages of using photography include time-consuming digitization, high costs for imagery collection, and lack of seasonal data. Recently, the availability of high-resolution satellite imagery has generated a new category of LULC data product. These new datasets have similar strengths to the aerial-photo-based LULC in that they possess the potential for refined definition of land-use categories and increased spatial resolution but also have the benefit of satellite-based classifications, such as repeatability for change analysis. LULC classification based on high-resolution satellite imagery is still in the early stages of development but merits greater attention because environmental-monitoring and landscape-modeling programs rely heavily on LULC data. This publication summarizes land-use and land-cover mapping activities for Alabama and Mississippi coastal areas within the U.S. Geological Survey (USGS) Northern Gulf of Mexico (NGOM) Ecosystem Change and Hazard Susceptibility Project boundaries. Existing LULC datasets will be described, as well as imagery data sources and ancillary data that may provide ground-truth or satellite training data for a forthcoming land-cover classification. Finally, potential areas for a high-resolution land-cover classification in the Alabama-Mississippi region will be identified.
Karayannis, Miltiades I; Efstathiou, Constantinos E
2012-12-15
In this review the history of chemistry and specifically the history and the significant steps of the evolution of analytical chemistry are presented. In chronological time spans, covering the ancient world, the middle ages, the period of the 19th century, and the three evolutional periods, from the verge of the 19th century to contemporary times, it is given information for the progress of chemistry and analytical chemistry. During this period, analytical chemistry moved gradually from its pure empirical nature to more rational scientific activities, transforming itself to an autonomous branch of chemistry and a separate discipline. It is also shown that analytical chemistry moved gradually from the status of exclusive serving the chemical science, towards serving, the environment, health, law, almost all areas of science and technology, and the overall society. Some recommendations are also directed to analytical chemistry educators concerning the indispensable nature of knowledge of classical analytical chemistry and the associated laboratory exercises and to analysts, in general, why it is important to use the chemical knowledge to make measurements on problems of everyday life. Copyright © 2012 Elsevier B.V. All rights reserved.
Haug, Joachim T; Haug, Carolin
2016-03-01
We re-investigated the fossil species tenera Oppel, 1862, an achelatan lobster (traditionally named Palinurina tenera) found in 150 million years old limestones of southern Germany. All known specimens attributed to this species show a mixture of characters, which in modern forms occur either in larvae or post-larval juveniles. Hence these specimens provide insight into a phase in ontogeny that is no longer present in the developmental sequence of any modern achelatan lobster, as the latter ones skip this phase and replace it by a drastic metamorphosis. Comparable cases have been described earlier, yet did only comprise single stages or two successive ones at most. In the here described case four developmental stages are preserved. The reconstructed ontogeny of tenera therefore represents the currently best known sequence of an early achelatan lobster that covers this specific intermediate phase. The largest known stage most likely still represents an immature of a yet undiscovered adult. These findings support the interpretation that early achelatan lobsters developed in a more gradual ontogenetic sequence than modern forms. It furthermore demonstrates that it was even more gradual than anticipated previously. Copyright © 2015 Elsevier Ltd. All rights reserved.
Intermediate filament protein nestin is expressed in developing meninges.
Yay, A; Ozdamar, S; Canoz, O; Baran, M; Tucer, B; Sonmez, M F
2014-01-01
Nestin is a type VI intermediate filament protein known as a marker for progenitor cells that can be mostly found in tissues during the embryonic and fetal periods. In our study, we aimed to determine the expression of nestin in meninges covering the brain tissue at different developmental stages and in the new born. In this study 10 human fetuses in different development stages between developmental weeks 9-34 and a newborn brain tissue were used. Fetuses in paraffin section were stained with H+E and nestin immunohistochemical staining protocol was performed. In this study, in the human meninges intense nestin expression was detected as early as in the 9th week of development. Intensity of this expression gradually decreased in later stages of development and nestin expression still persisted in a small population of newborn meningeal cells. In the present study, nestin positive cells gradually diminished in the developing and maturing meninges during the fetal period. This probably depends on initiation of a decrease in nestin expression and replacement with other tissue-specific intermediate filaments while the differentiation process continues. These differences can make significant contributions to the investigation and diagnosis of various pathological disorders (Tab. 1, Fig. 3, Ref. 36).
Sun, Ran-Hao; Chen, Li-Ding; Wang, Wei; Wang, Zhao-Ming
2012-06-01
Understanding the effect of land cover pattern on nutrient losses is of great importance in management of water resources. The extensive application of mechanism models is limited in large-scale watersheds owing to the intensive data and calibration requirements. On the other hand, the traditional landscape indexes only take the areas and types of land cover into account, considering less about their topographic features and spatial patterns. We constructed a location-weighted landscape index (LWLI) based on the Lorenz curve, which plots the cumulative proportion of areas for sink and source landscapes respectively against cumulative proportion of their relative location to the outlet in a watershed, including relative elevation, distance and slope. We assessed the effect of land cover pattern on total nitrogen losses in the Haihe River. Firstly, 26 watersheds were derived from 1: 250 000 digital elevation model (DEM), and their "source" and "sink" landscape types were identified from Landsat TM images in 2007. The source" landscapes referred to the paddy land, dry land and residential area, correspondingly the "sink" landscapes referred to the forest and grassland. Secondly, LWLI was calculated according to the landscape types and spatial patterns for each watershed. Thirdly, we accessed the effect of land cover pattern on total nitrogen (TN) flux according to the value of LWLI, comparing with the area proportion of sink-source landscapes. The correlation coefficients were different in three parts of Haihe River, i. e., 0.86, 0.67 and 0.65 in the Yanshan Mts, Taihang Mts and lower Haihe River. The results showed strong correlations between TN and LWLI in contrast to the weak correlations between TN and area proportion of sink and source landscape types. This study indicates the spatial pattern of land cover is essential for accessing the nutrient losses, and the location-weighted landscape pattern analysis may be an alternate to existing water quality models, especially in large watershed scales. The sink-source index is sufficiently simple that it can be compared across watersheds and be easily interpreted, and potentially be used in landscape pattern optimal designing and planning.
Simonaitis, Linas; McDonald, Clement J
2009-10-01
The utility of National Drug Codes (NDCs) and drug knowledge bases (DKBs) in the organization of prescription records from multiple sources was studied. The master files of most pharmacy systems include NDCs and local codes to identify the products they dispense. We obtained a large sample of prescription records from seven different sources. These records carried a national product code or a local code that could be translated into a national product code via their formulary master. We obtained mapping tables from five DKBs. We measured the degree to which the DKB mapping tables covered the national product codes carried in or associated with the sample of prescription records. Considering the total prescription volume, DKBs covered 93.0-99.8% of the product codes from three outpatient sources and 77.4-97.0% of the product codes from four inpatient sources. Among the in-patient sources, invented codes explained 36-94% of the noncoverage. Outpatient pharmacy sources rarely invented codes, which comprised only 0.11-0.21% of their total prescription volume, compared with inpatient pharmacy sources for which invented codes comprised 1.7-7.4% of their prescription volume. The distribution of prescribed products was highly skewed, with 1.4-4.4% of codes accounting for 50% of the message volume and 10.7-34.5% accounting for 90% of the message volume. DKBs cover the product codes used by outpatient sources sufficiently well to permit automatic mapping. Changes in policies and standards could increase coverage of product codes used by inpatient sources.
Ammonia pollution characteristics of centralized drinking water sources in China.
Fu, Qing; Zheng, Binghui; Zhao, Xingru; Wang, Lijing; Liu, Changming
2012-01-01
The characteristics of ammonia in drinking water sources in China were evaluated during 2005-2009. The spatial distribution and seasonal changes of ammonia in different types of drinking water sources of 22 provinces, 5 autonomous regions and 4 municipalities were investigated. The levels of ammonia in drinking water sources follow the order of river > lake/reservoir > groundwater. The levels of ammonia concentration in river sources gradually decreased from 2005 to 2008, while no obvious change was observed in the lakes/reservoirs and groundwater drinking water sources. The proportion of the type of drinking water sources is different in different regions. In river drinking water sources, the ammonia level was varied in different regions and changed seasonally. The highest value and wide range of annual ammonia was found in South East region, while the lowest value was found in Southwest region. In lake/reservoir drinking water sources, the ammonia levels were not varied obviously in different regions. In underground drinking water sources, the ammonia levels were varied obviously in different regions due to the geological permeability and the natural features of regions. In the drinking water sources with higher ammonia levels, there are enterprises and wastewater drainages in the protected areas of the drinking water sources.
Assessing urban forest canopy cover using airborne or satellite imagery
Jeffrey T. Walton; David J. Nowak; Eric J. Greenfield
2008-01-01
With the availability of many sources of imagery and various digital classification techniques, assessing urban forest canopy cover is readily accessible to most urban forest managers. Understanding the capability and limitations of various types of imagery and classification methods is essential to interpreting canopy cover values. An overview of several remote...
40 CFR 63.2132 - What parts of my plant does this subpart cover?
Code of Federal Regulations, 2014 CFR
2014-07-01
... Yeast What This Subpart Covers § 63.2132 What parts of my plant does this subpart cover? (a) This... cerevisiae at a nutritional yeast manufacturing facility. (b) The affected source is the collection of equipment used in the manufacture of the nutritional yeast species Saccharomyces cerevisiae. This collection...
40 CFR 63.2132 - What parts of my plant does this subpart cover?
Code of Federal Regulations, 2013 CFR
2013-07-01
... Yeast What This Subpart Covers § 63.2132 What parts of my plant does this subpart cover? (a) This... cerevisiae at a nutritional yeast manufacturing facility. (b) The affected source is the collection of equipment used in the manufacture of the nutritional yeast species Saccharomyces cerevisiae. This collection...
40 CFR 63.2132 - What parts of my plant does this subpart cover?
Code of Federal Regulations, 2012 CFR
2012-07-01
... Yeast What This Subpart Covers § 63.2132 What parts of my plant does this subpart cover? (a) This... cerevisiae at a nutritional yeast manufacturing facility. (b) The affected source is the collection of equipment used in the manufacture of the nutritional yeast species Saccharomyces cerevisiae. This collection...
Code of Federal Regulations, 2011 CFR
2011-07-01
... covered calcium carbide furnaces with wet air pollution control devices subcategory. 424.40 Section 424.40... FERROALLOY MANUFACTURING POINT SOURCE CATEGORY Covered Calcium Carbide Furnaces With Wet Air Pollution... with wet air pollution control devices subcategory. The provisions of this subpart are applicable to...
Code of Federal Regulations, 2010 CFR
2010-07-01
... covered calcium carbide furnaces with wet air pollution control devices subcategory. 424.40 Section 424.40... FERROALLOY MANUFACTURING POINT SOURCE CATEGORY Covered Calcium Carbide Furnaces With Wet Air Pollution... with wet air pollution control devices subcategory. The provisions of this subpart are applicable to...
Code of Federal Regulations, 2013 CFR
2013-07-01
... covered calcium carbide furnaces with wet air pollution control devices subcategory. 424.40 Section 424.40... FERROALLOY MANUFACTURING POINT SOURCE CATEGORY Covered Calcium Carbide Furnaces With Wet Air Pollution... with wet air pollution control devices subcategory. The provisions of this subpart are applicable to...
Code of Federal Regulations, 2014 CFR
2014-07-01
... covered calcium carbide furnaces with wet air pollution control devices subcategory. 424.40 Section 424.40... FERROALLOY MANUFACTURING POINT SOURCE CATEGORY Covered Calcium Carbide Furnaces With Wet Air Pollution... with wet air pollution control devices subcategory. The provisions of this subpart are applicable to...
Code of Federal Regulations, 2012 CFR
2012-07-01
... covered calcium carbide furnaces with wet air pollution control devices subcategory. 424.40 Section 424.40... FERROALLOY MANUFACTURING POINT SOURCE CATEGORY Covered Calcium Carbide Furnaces With Wet Air Pollution... with wet air pollution control devices subcategory. The provisions of this subpart are applicable to...
NASA Astrophysics Data System (ADS)
Matsumoto, Y.; Inoue, T.
2009-12-01
The role of fine particle organic matters (FPOM) is important in the energy source of benthic organisms and microbes and organic transportation from terrestrial water ecosystem to costal water ecosystem. Accumulated FPOM at a river bed is called Fine benthic organic matter (FBOM). It is considered that FBOM is the source of FPOM at the flood period. But the mechanism of the accumulation and the flush of FBOM are not concerned in research. In this research, we examined effects of hydrological and biological factors on FBOM. The purpose of this research is 1) the routine sampling of FBOM for the collecting basic FBOM data, 2) the examination of the relationship between of the water level or the current velocity and the mass of FBOM, 3) the determination of the FBOM mass of microbial decomposition by a double exponential model. This study was conducted in Tomoe river which was substream of Yahagi river whose length was 117km, located at central of Honshu Island, Japan. The above sea level of the sampling site is 320m and 75km upstream from an estuary. The drainage basin is covered over 90 % by a forest. The stream bed is covered by the coarse fragment and sand. The barrage of a hydroelectric power plant is located at 100m downstream from the sampling site. The sampling area was 30 cm diameter divided by the polyethylene barrel. These samples were divided into two fractions: Coarse-Sediment, over 1mm and Fine-Sediment, 2mm - 63μm. FBOM and CBOM were determined from the amount of carbon containing in Fine-Sediment and Coarse-Sediment. Total C and Total N were measured by CN coder. The water level of river was measured by a level rod and the surface current velocity was measured by a floater at a sampling day. Sampling of FBOM was performed every 2 weeks from the end of August 2008 to the middle of April 2009. The heavy precipitation(98.0 mm/day) was measured at the end of August. This precipitation caused highest water level and fastest current velocity of river during this investigation. The water level of river decreased gradually after the end of August. There were small rain events during September to December, but these events did not let the water level increased. The mass of FBOM collected 0.2(g/m2) at the end of August. The mass of FBOM was increased and decreased between September and October. The mass of FBOM was 4.5(g/m2) at the end of October, subsequently decreased 0.5(g/m2) gradually at April 2009. These investigations showed that FBOM is decreased severely by the large flood, but the other factors are influenced to the FBOM fluctuation. As the effect of hydrology on FBOM, the mass of FBOM was decreased with increasing the water level during the water level increasing period. But the mass of FBOM had the negative relationship with the current velocity during the water level deceasing period. CN ratio of CBOM was larger than that of FBOM. This means that FBOM is biodegraded by organisms from CBOM or CPOM. Then the calculated result of the ratio of decomposition of FBOM was showed that the biodegraded mass of FBOM from CBOM might be less affected than hydrological factors during 2 weeks at investigation site.
Prestele, Reinhard; Alexander, Peter; Rounsevell, Mark D. A.; ...
2016-05-02
Model-based global projections of future land use and land cover (LULC) change are frequently used in environmental assessments to study the impact of LULC change on environmental services and to provide decision support for policy. These projections are characterized by a high uncertainty in terms of quantity and allocation of projected changes, which can severely impact the results of environmental assessments. In this study, we identify hotspots of uncertainty, based on 43 simulations from 11 global-scale LULC change models representing a wide range of assumptions of future biophysical and socio-economic conditions. We attribute components of uncertainty to input data, modelmore » structure, scenario storyline and a residual term, based on a regression analysis and analysis of variance. From this diverse set of models and scenarios we find that the uncertainty varies, depending on the region and the LULC type under consideration. Hotspots of uncertainty appear mainly at the edges of globally important biomes (e.g. boreal and tropical forests). Our results indicate that an important source of uncertainty in forest and pasture areas originates from different input data applied in the models. Cropland, in contrast, is more consistent among the starting conditions, while variation in the projections gradually increases over time due to diverse scenario assumptions and different modeling approaches. Comparisons at the grid cell level indicate that disagreement is mainly related to LULC type definitions and the individual model allocation schemes. We conclude that improving the quality and consistency of observational data utilized in the modeling process as well as improving the allocation mechanisms of LULC change models remain important challenges. Furthermore, current LULC representation in environmental assessments might miss the uncertainty arising from the diversity of LULC change modeling approaches and many studies ignore the uncertainty in LULC projections in assessments of LULC change impacts on climate, water resources or biodiversity.« less
Prestele, Reinhard; Alexander, Peter; Rounsevell, Mark D A; Arneth, Almut; Calvin, Katherine; Doelman, Jonathan; Eitelberg, David A; Engström, Kerstin; Fujimori, Shinichiro; Hasegawa, Tomoko; Havlik, Petr; Humpenöder, Florian; Jain, Atul K; Krisztin, Tamás; Kyle, Page; Meiyappan, Prasanth; Popp, Alexander; Sands, Ronald D; Schaldach, Rüdiger; Schüngel, Jan; Stehfest, Elke; Tabeau, Andrzej; Van Meijl, Hans; Van Vliet, Jasper; Verburg, Peter H
2016-12-01
Model-based global projections of future land-use and land-cover (LULC) change are frequently used in environmental assessments to study the impact of LULC change on environmental services and to provide decision support for policy. These projections are characterized by a high uncertainty in terms of quantity and allocation of projected changes, which can severely impact the results of environmental assessments. In this study, we identify hotspots of uncertainty, based on 43 simulations from 11 global-scale LULC change models representing a wide range of assumptions of future biophysical and socioeconomic conditions. We attribute components of uncertainty to input data, model structure, scenario storyline and a residual term, based on a regression analysis and analysis of variance. From this diverse set of models and scenarios, we find that the uncertainty varies, depending on the region and the LULC type under consideration. Hotspots of uncertainty appear mainly at the edges of globally important biomes (e.g., boreal and tropical forests). Our results indicate that an important source of uncertainty in forest and pasture areas originates from different input data applied in the models. Cropland, in contrast, is more consistent among the starting conditions, while variation in the projections gradually increases over time due to diverse scenario assumptions and different modeling approaches. Comparisons at the grid cell level indicate that disagreement is mainly related to LULC type definitions and the individual model allocation schemes. We conclude that improving the quality and consistency of observational data utilized in the modeling process and improving the allocation mechanisms of LULC change models remain important challenges. Current LULC representation in environmental assessments might miss the uncertainty arising from the diversity of LULC change modeling approaches, and many studies ignore the uncertainty in LULC projections in assessments of LULC change impacts on climate, water resources or biodiversity. © 2016 The Authors. Global Change Biology Published by John Wiley & Sons Ltd.
The transition of North Atlantic dust deposition and Saharan landscape during the Holocene
NASA Astrophysics Data System (ADS)
Egerer, S.; Claussen, M.; Stanelle, T.; Reick, C. H.
2017-12-01
The sudden increase in North Atlantic dust deposition about 5 ka BP indicated by sediment records along the West African margin has been associated with an abrupt end of the African Humid Period (AHP). We perform several time slice simulations from 8 ka BP until the pre-industrial era to explore changes in the Holocene dust cycle. To do so, we use the coupled aerosol-climate model ECHAM6-HAM2 including interactive vegetation and dust, whereas ocean conditions and lakes are prescribed. The interactive coupling of vegetation, dust and atmosphere allows to set the dynamics of North Atlantic dust deposition in context to Holocene climate and landscape change in North Africa.In agreement with marine sediment records, we find an abrupt increase in simulated dust deposition at the location of the core sites roughly between 6 and 4 ka BP. Accordingly, dust emission in the North-west Sahara increases rapidly indicating that dust was transported by the same wind systems throughout the Holocene. The sudden increase in dust emission in the North-west Sahara is partly a consequence of a fast decline of vegetation cover from 22°N to 18°N due to vegetation-climate feedbacks and the rapid replacement of shrubs by grasses. Additionally, the prescribed strong but gradual reduction of lake surface area enforces accelerated dust release as former areas covered by lakes turn into highly productive dust sources. Changes in the Saharan landscape and dust emission south of 18°N and in the eastern Sahara as well as changes in atmospheric circulation play a minor role in driving the dynamics of North Atlantic dust deposition at the specific core sites. Our study emphasizes spatial and temporal differences in the transition of North African landscape implying that implications from local data records to large scales have to be treated with caution.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Prestele, Reinhard; Alexander, Peter; Rounsevell, Mark D. A.
Model-based global projections of future land use and land cover (LULC) change are frequently used in environmental assessments to study the impact of LULC change on environmental services and to provide decision support for policy. These projections are characterized by a high uncertainty in terms of quantity and allocation of projected changes, which can severely impact the results of environmental assessments. In this study, we identify hotspots of uncertainty, based on 43 simulations from 11 global-scale LULC change models representing a wide range of assumptions of future biophysical and socio-economic conditions. We attribute components of uncertainty to input data, modelmore » structure, scenario storyline and a residual term, based on a regression analysis and analysis of variance. From this diverse set of models and scenarios we find that the uncertainty varies, depending on the region and the LULC type under consideration. Hotspots of uncertainty appear mainly at the edges of globally important biomes (e.g. boreal and tropical forests). Our results indicate that an important source of uncertainty in forest and pasture areas originates from different input data applied in the models. Cropland, in contrast, is more consistent among the starting conditions, while variation in the projections gradually increases over time due to diverse scenario assumptions and different modeling approaches. Comparisons at the grid cell level indicate that disagreement is mainly related to LULC type definitions and the individual model allocation schemes. We conclude that improving the quality and consistency of observational data utilized in the modeling process as well as improving the allocation mechanisms of LULC change models remain important challenges. Furthermore, current LULC representation in environmental assessments might miss the uncertainty arising from the diversity of LULC change modeling approaches and many studies ignore the uncertainty in LULC projections in assessments of LULC change impacts on climate, water resources or biodiversity.« less
NASA Astrophysics Data System (ADS)
Clark, Peter U.; Archer, David; Pollard, David; Blum, Joel D.; Rial, Jose A.; Brovkin, Victor; Mix, Alan C.; Pisias, Nicklas G.; Roy, Martin
2006-12-01
The emergence of low-frequency, high-amplitude, quasi-periodic (˜100-kyr) glacial variability during the middle Pleistocene in the absence of any significant change in orbital forcing indicates a fundamental change internal to the climate system. This middle Pleistocene transition (MPT) began 1250 ka and was complete by 700 ka. Its onset was accompanied by decreases in sea surface temperatures (SSTs) in the North Atlantic and tropical-ocean upwelling regions and by an increase in African and Asian aridity and monsoonal intensity. During the MPT, long-term average ice volume gradually increased by ˜50 m sea-level equivalent, whereas low-frequency ice-volume variability experienced a 100-kyr lull centered on 1000 ka followed by its reappearance ˜900 ka, although as a broad band of power rather than a narrow, persistent 100-kyr cycle. Additional changes at 900 ka indicate this to be an important time during the MPT, beginning with an 80-kyr event of extreme SST cooling followed by the partial recovery and subsequent stabilization of long-term North Atlantic and tropical ocean SSTs, increasing Southern Ocean SST variability primarily associated with warmer interglacials, the loss of permanent subpolar sea-ice cover, and the emergence of low-frequency variability in Pacific SSTs and global deep-ocean circulation. Since 900 ka, ice sheets have been the only component of the climate system to exhibit consistent low-frequency variability. With the exception of a near-universal organization of low-frequency power associated with marine isotope stages 11 and 12, all other components show an inconsistent distribution of power in frequency-time space, suggesting a highly nonlinear system response to orbital and ice-sheet forcing. Most hypotheses for the origin of the MPT invoke a response to a long-term cooling, possibly induced by decreasing atmospheric pCO 2. None of these hypotheses, however, accounts for the geological constraint that the earliest Northern Hemisphere ice sheets covered a similar or larger area than those that followed the MPT. Given that the MPT was associated with an increase in ice volume, this constraint requires that post-MPT ice sheets were substantially thicker than pre-MPT ice sheets, indicating a change in subglacial conditions that influence ice dynamics. We review evidence in support of the hypothesis that such an increase in ice thickness occurred as crystalline Precambrian Shield bedrock became exposed by glacial erosion of a thick mantle of regolith. This exposure of a high-friction substrate caused thicker ice sheets, with an attendant change in their response to the orbital forcing. Marine carbon isotope data indicate a rapid transfer of organic carbon to inorganic carbon in the ocean system during the MPT. If this carbon came from terrigenous sources, an increase in atmospheric pCO 2 would be likely, which is inconsistent with evidence for widespread cooling, Apparently rapid carbon transfer from terrestrial sources is difficult to reconcile with gradual erosion of regolith. A more likely source of organic carbon and nutrients (which would mitigate pCO 2 rise) is from shelf and upper slope marine sediments, which were fully exposed for the first time in millions of years in response to thickening ice sheets and falling sealevels during the MPT. Modeling indicates that regolith erosion and resulting exposure of crystalline bedrock would cause an increase in long-term silicate weathering rates, in good agreement with marine Sr and Os isotopic records. We use a carbon cycle model to show that a post-MPT increase in silicate weathering rates would lower atmospheric pCO 2 by 7-12 ppm, suggesting that the attendant cooling may have been an important feedback in causing the MPT.
Annual global tree cover estimated by fusing optical and SAR satellite observations
NASA Astrophysics Data System (ADS)
Feng, M.; Sexton, J. O.; Channan, S.; Townshend, J. R.
2017-12-01
Tree cover defined structurally as the proportional, vertically projected area of vegetation (including leaves, stems, branches, etc.) of woody plants above a given height affects terrestrial energy and water exchanges, photosynthesis and transpiration, net primary production, and carbon and nutrient fluxes. Tree cover provides a measurable attribute upon which forest cover may be defined. Changes in tree cover over time can be used to monitor and retrieve site-specific histories of forest disturbance, succession, and degradation. Measurements of Earth's tree cover have been produced at regional, national, and global extents. However, most representations are static, and those for which multiple time periods have been produced are neither intended nor adequate for consistent, long-term monitoring. Moreover, although a substantial proportion of change has been shown to occur at resolutions below 250 m, existing long-term, Landsat-resolution datasets are either produced as static layers or with annual, five- or ten-year temporal resolution. We have developed an algorithms to retrieve seamless and consistent, sub-hectare resolution estimates of tree-canopy from optical and radar satellite data sources (e.g., Landsat, Sentinel-2, and ALOS-PALSAR). Our approach to estimation enables assimilation of multiple data sources and produces estimates of both cover and its uncertainty at the scale of pixels. It has generated the world's first Landsat-based percent tree cover dataset in 2013. Our previous algorithms are being adapted to produce prototype percent-tree and water-cover layers globally in 2000, 2005, and 2010—as well as annually over North and South America from 2010 to 2015—from passive-optical (Landsat and Sentinel-2) and SAR measurements. Generating a global, annual dataset is beyond the scope of this support; however, North and South America represent all of the world's major biomes and so offer the complete global range of environmental sources of error and uncertainty.
Survey methods for assessing land cover map accuracy
Nusser, S.M.; Klaas, E.E.
2003-01-01
The increasing availability of digital photographic materials has fueled efforts by agencies and organizations to generate land cover maps for states, regions, and the United States as a whole. Regardless of the information sources and classification methods used, land cover maps are subject to numerous sources of error. In order to understand the quality of the information contained in these maps, it is desirable to generate statistically valid estimates of accuracy rates describing misclassification errors. We explored a full sample survey framework for creating accuracy assessment study designs that balance statistical and operational considerations in relation to study objectives for a regional assessment of GAP land cover maps. We focused not only on appropriate sample designs and estimation approaches, but on aspects of the data collection process, such as gaining cooperation of land owners and using pixel clusters as an observation unit. The approach was tested in a pilot study to assess the accuracy of Iowa GAP land cover maps. A stratified two-stage cluster sampling design addressed sample size requirements for land covers and the need for geographic spread while minimizing operational effort. Recruitment methods used for private land owners yielded high response rates, minimizing a source of nonresponse error. Collecting data for a 9-pixel cluster centered on the sampled pixel was simple to implement, and provided better information on rarer vegetation classes as well as substantial gains in precision relative to observing data at a single-pixel.
Expansion of chromospheric matter in the gradual phase of solar flares
NASA Technical Reports Server (NTRS)
Ohki, K.
1975-01-01
Interferometric observations at 17 GHz of several small X-ray flares are presented along with soft X-ray observations of preflare active regions to show that a large mass increase accompanies the formation of an X-ray hot region in the corona. The total amount of energy contained in a hot coronal region is estimated, and a model is proposed in which a significant amount of the hot matter is supplied to the corona from the chromosphere during each flare. According to this model, energy produced by some coronal instability is transported by thermal conduction to the chromosphere, where dense gas is heated and subsequently expands into the corona. It is shown that impulsive heating of the chromosphere by nonthermal electrons cannot be the energy source of this model because the total energy supplied to the hot region during the gradual phase must be much greater than that supplied during the impulsive phase.
SOURCEBOOK: NOX CONTROL TECHNOLOGY DATA
The report, a compilation of available information on the control of nitrogen oxide (NOx) emissions from stationary sources, is provided to assist new source permitting activities by regulatory agencies. he sources covered are combustion turbines, internal combustion engines, non...
Getting the lead out: understanding risks in the distribution ...
This presentation discusses the importance of the water distribution system as a component of the source-to-tap continuum in public health protection. Issues covered include: understanding source water quality changes and their impacts throughout the system; use of mitigation measures such as filters); and holistic approaches and/or strategies that could be used to avoid unintended consequences of decisions from source to tap. Invited presentation on topics indicated as of interest. With exposure to lead as the context, this presentation discusses the importance of the water distribution system as a component of the source-to-tap continuum in public health protection. Issues covered include: understanding source water quality changes and their impacts throughout the system; use of mitigation measures such as filters); and holistic approaches and/or strategies that could be used to avoid unintended consequences of decisions from source to tap.
NASA Astrophysics Data System (ADS)
Hyer, E. J.; Reid, J. S.
2006-12-01
As more forecast models aim to include aerosol and chemical species, there is a need for source functions for biomass burning emissions that are accurate, robust, and operable in real-time. NAAPS is a global aerosol forecast model running every six hours and forecasting distributions of biomass burning, industrial sulfate, dust, and sea salt aerosols. This model is run operationally by the U.S. Navy as an aid to planning. The smoke emissions used as input to the model are calculated from the data collected by the FLAMBE system, driven by near-real-time active fire data from GOES WF_ABBA and MODIS Rapid Response. The smoke source function uses land cover data to predict properties of detected fires based on literature data from experimental burns. This scheme is very sensitive to the choice of land cover data sets. In areas of rapid land cover change, the use of static land cover data can produce artifactual changes in emissions unrelated to real changes in fire patterns. In South America, this change may be as large as 40% over five years. We demonstrate the impact of a modified land cover scheme on FLAMBE emissions and NAAPS forecasts, including a fire size algorithm developed using MODIS burned area data. We also describe the effects of corrections to emissions estimates for cloud and satellite coverage. We outline areas where existing data sources are incomplete and improvements are required to achieve accurate modeling of biomass burning emissions in real time.
Temporal variation in spatial sources of mercury loading to rivers (presentation)
Source areas within the Fox River watershed (WI, USA) were mapped for individual discharge events. The spatial distribution of source areas varied between, and over the duration of, individual discharge events. The percent contribution of runoff by land cover type within source a...
Remote sensing of land use/cover changes and its effect on wind erosion potential in southern Iran
Sameni, Abdolmajid; Fallah Shamsi, Seyed Rashid; Bartholomeus, Harm
2016-01-01
Wind erosion is a complex process influenced by different factors. Most of these factors are stable over time, but land use/cover and land management practices are changing gradually. Therefore, this research investigates the impact of changing land use/cover and land management on wind erosion potential in southern Iran. We used remote sensing data (Landsat ETM+ and Landsat 8 imagery of 2004 and 2013) for land use/cover mapping and employed the Iran Research Institute of Forest and Rangeland (IRIFR) method to estimate changes in wind erosion potential. For an optimal mapping, the performance of different classification algorithms and input layers was tested. The amount of changes in wind erosion and land use/cover were quantified using cross-tabulation between the two years. To discriminate land use/cover related to wind erosion, the best results were obtained by combining the original spectral bands with synthetic bands and using Maximum Likelihood classification algorithm (Kappa Coefficient of 0.8 and 0.9 for Landsat ETM+ and Landsat 8, respectively). The IRIFR modelling results indicate that the wind erosion potential has increased over the last decade. The areas with a very high sediment yield potential have increased, whereas the areas with a low, medium, and high sediment yield potential decreased. The area with a very low sediment yield potential have remained constant. When comparing the change in erosion potential with land use/cover change, it is evident that soil erosion potential has increased mostly in accordance with the increase of the area of agricultural practices. The conversion of rangeland to agricultural land was a major land-use change which lead to more agricultural practices and associated soil loss. Moreover, results indicate an increase in sandification in the study area which is also a clear evidence of increasing in soil erosion. PMID:27547511
The formation of helical mesoporous silica nanotubes
NASA Astrophysics Data System (ADS)
Wan, Xiaobing; Pei, Xianfeng; Zhao, Huanyu; Chen, Yuanli; Guo, Yongmin; Li, Baozong; Hanabusa, Kenji; Yang, Yonggang
2008-08-01
Three chiral cationic gelators were synthesized. They can form translucent hydrogels in pure water. These hydrogels become highly viscous liquids under strong stirring. Mesoporous silica nanotubes with coiled pore channels in the walls were prepared using the self-assemblies of these gelators as templates. The mechanism of the formation of this hierarchical nanostructure was studied using transmission electron microscopy at different reaction times. The results indicated that there are some interactions between the silica source and the gelator. The morphologies of the self-assemblies of gelators changed gradually during the sol-gel transcription process. It seems that the silica source directed the organic self-assemblies into helical nanostructures.
Update of NIST half-life results corrected for ionization chamber source-holder instability.
Unterweger, M P; Fitzgerald, R
2014-05-01
As reported at the ICRM 2011, it was discovered that the source holder used for calibrations in the NIST 4πγ ionization chamber (IC) was not stable. This has affected a large number of half-life measurement results previously reported and used in compilations of nuclear data. Corrections have been made on all of the half-life data based on the assumption that the changes to the ionization chamber response were gradual. The corrections are energy dependent and therefore radionuclide specific. This presentation will review our results and present the recommended changes in half-life values and/or uncertainties. © 2013 Published by Elsevier Ltd.
Primary water chemistry improvement for radiation exposure reduction at Japanese PWR Plants
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nishizawa, Eiichi
1995-03-01
Radiation exposure during the refueling outages at Japanese Pressurized Water Reactor (PWR) Plants has been gradually decreased through continuous efforts keeping the radiation dose rates at relatively low level. The improvement of primary water chemistry in respect to reduction of the radiation sources appears as one of the most important contributions to the achieved results and can be classified by the plant operation conditions as follows
The new health legacy: when pertussis becomes a heritage transmitted from mothers to infants.
Zouari, Asma; Smaoui, Hanen; Bousnina, Souad; Menif, Khaled; Ben Jaballah, Najla; Kechrid, Amel
2011-10-01
Despite high vaccination coverage rates, there has been a gradual increase in reported pertussis cases. Although whooping cough affects all ages, young infants continue to suffer the greatest pertussis disease burden. Adolescents and adults are the primary source of infection for young babies. In this paper, we report two cases involving the likely transmission of pertussis from mothers to infants in Tunisia.
Witnessing the Gradual Slowdown of Powerful Extragalactic Jets: The X-Ray-Optical-Radio Connection
NASA Technical Reports Server (NTRS)
Georganopoulos, Markos; Kazanas, Demosthenes
2004-01-01
A puzzling feature of the Chandra-detected quasar jets is that their X-ray emission decreases faster along the jet than their radio emission, resulting from an outward-increasing radio-to-X-ray ratio. In some sources this behavior is so extreme that the radio emission peak is located clearly downstream of that of the X-rays. This is a rather unanticipated behavior given that the inverse Compton nature of the X-rays and the synchrotron radio emission are attributed to roughly the same electrons of the jet's nonthermal electron distribution. In this letter we show that this morphological behavior can result from the gradual deceleration of a relativistic flow and that the offsets in peak emission at different wavelengths carry the imprint of this deceleration. This notion is consistent with another recent finding, namely, that the jets feeding the terminal hot spots of powerful radio galaxies and quasars are still relativistic with Lorentz factors GAMMA approximately 2-3. The picture of the kinematics of powerful jets emerging from these considerations is that they remain relativistic as they gradually decelerate from kiloparsec scales to the hot spots, where, in a final collision with the intergalactic medium, they slow down rapidly to the subrelativistic velocities of the hot spot advance speed.
Hydrogen energy: A bibliography with abstracts. Cumulative volume, 1953 - 1973
NASA Technical Reports Server (NTRS)
Cox, K. E.
1974-01-01
A bibliography on hydrogen as an energy source is presented. Approximately 8,000 documents are abstracted covering the period 1953 through 1973. Topics covered include: production, utilization, transmission, distribution, storage, and safety.
Statistical Sources on Women: A Critical Evaluation.
ERIC Educational Resources Information Center
Krikos, Linda A.
1996-01-01
Evaluates 27 print statistical sources that specifically cover women and were published in English during the 1990s in the areas of criminal justice; economics, labor, and income; education; health; lesbians; general sources; international women; Europe; and politics. (Author/LRW)
Tan, Z.; Liu, S.; Johnston, C.A.; Liu, J.; Tieszen, L.L.
2006-01-01
Our ability to forecast the role of ecosystem processes in mitigating global greenhouse effects relies on understanding the driving forces on terrestrial C dynamics. This study evaluated the controls on soil organic C (SOC) changes from 1973 to 2000 in the northwest Great Plains. SOC source-sink relationships were quantified using the General Ensemble Biogeochemical Modeling System (GEMS) based on 40 randomly located 10 × 10 km2 sample blocks. These sample blocks were aggregated into cropland, grassland, and forestland groups based on land cover composition within each sample block. Canonical correlation analysis indicated that SOC source-sink relationship from 1973 to 2000 was significantly related to the land cover type while the change rates mainly depended on the baseline SOC level and annual precipitation. Of all selected driving factors, the baseline SOC and nitrogen levels controlled the SOC change rates for the forestland and cropland groups, while annual precipitation determined the C source-sink relationship for the grassland group in which noticeable SOC sink strength was attributed to the conversion from cropped area to grass cover. Canonical correlation analysis also showed that grassland ecosystems are more complicated than others in the ecoregion, which may be difficult to identify on a field scale. Current model simulations need further adjustments to the model input variables for the grass cover-dominated ecosystems in the ecoregion.
49 CFR 232.107 - Air source requirements and cold weather operations.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 49 Transportation 4 2011-10-01 2011-10-01 false Air source requirements and cold weather... source requirements and cold weather operations. (a) Monitoring plans for yard air sources. (1) A... to the equipment and territory of that railroad to cover safe train operations during cold weather...
Multiwavelength study of the low-luminosity outbursting young star HBC 722
NASA Astrophysics Data System (ADS)
Kóspál, Á.; Ábrahám, P.; Acosta-Pulido, J. A.; Dunham, M. M.; García-Álvarez, D.; Hogerheijde, M. R.; Kun, M.; Moór, A.; Farkas, A.; Hajdu, G.; Hodosán, G.; Kovács, T.; Kriskovics, L.; Marton, G.; Molnár, L.; Pál, A.; Sárneczky, K.; Sódor, Á.; Szakáts, R.; Szalai, T.; Szegedi-Elek, E.; Szing, A.; Tóth, I.; Vida, K.; Vinkó, J.
2016-11-01
Context. HBC 722 (V2493 Cyg) is a young eruptive star in outburst since 2010. Spectroscopic evidence suggests that the source is an FU Orionis-type object, with an atypically low outburst luminosity. Aims: Because it was well characterized in the pre-outburst phase, HBC 722 is one of the few FUors from which we can learn about the physical changes and processes associated with the eruption, including the role of the circumstellar environment. Methods: We monitored the source in the BVRIJHKS bands from the ground and at 3.6 and 4.5 μm from space with the Spitzer Space Telescope. We analyzed the light curves and studied the evolving spectral energy distribution by fitting a series of steady accretion disk models at many epochs covering the outburst. We also analyzed the spectral properties of the source based on our new optical and infrared spectra, comparing our line inventory with those published in the literature for other epochs. We also mapped HBC 722 and its surroundings at millimeter wavelengths. Results: From the light-curve analysis we conclude that the first peak of the outburst in 2010 September was mainly due to an abrupt increase in the accretion rate in the innermost part of the system. This was followed after a few months by a long-term process, when the brightening of the source was mainly due to a gradual increase in the accretion rate and the emitting area. Our new observations show that the source is currently in a constant plateau phase. We found that the optical spectrum was similar in the first peak and following periods, but around the peak the continuum was bluer and the Hα profile changed significantly between 2012 and 2013. The source was not detected in the millimeter continuum, but we discovered a flattened molecular gas structure with a diameter of 1700 au and mass of 0.3 M⊙ centered on HBC 722. Conclusions: While the first brightness peak might be interpreted as a rapid fall of piled-up material from the inner disk onto the star, the later monotonic flux rise suggests the outward expansion of a hot component according to a previously described theory. Our study of HBC 722 demonstrates that accretion-related outbursts can occur in young stellar objects even with very low-mass disks in the late Class II phase. This work is based on observations made with the Spitzer Space Telescope. Spitzer is operated by the Jet Propulsion Laboratory, California Institute of Technology under a contract with NASA.
The Mount Logan (Yukon) Ice Cores: Preliminary Results
NASA Astrophysics Data System (ADS)
Fisher, D. A.
2004-05-01
Three ice cores were taken at different elevations on or near My Logan in the years 2001 and 2002. The summit core (PRCol) comes from the summit plateau ( 5340 masl, length 187 m to bedrock, mean temperature -29 C ) and was done by the Geological Survey of Canada. The NIPR group cored 210m on the flanks of the mountain at King Col (4200 masl mean temperature -16C) and the UNH group cored 20 km from the mountain at Eclipse "Dome" (3015 masl,length 345 m mean temperature -5C) . The three cores were done cooperatively by GSC, NIPR and UNH and cover nominally 30 ka, 1 ka and 2ka respectively . Located very close to the Gulf of Alaska these core records are thought to reflect the climate history of the Pacific Ocean and having three widely spaced elevations, the sites "see" different distances to different sources. The lowest site (Eclipse) has excellent seasonals but a very muted δ 18O history with no obvious little ice age, whereas the most recent 1ka of the PRCol summit sites contains two very large and sudden δ 18O and d (deuterium excess) shifts at 1850 AD and ~ 800 AD. The δ 18O shifts which happen from one year to the next are about 4 o/oo . The summit site (PRCol) δ 18O response is "backwards", ie the Little Ice Age δ 18O values are 4 o/oo more positive than recent ones. The PRCol δ 18O and d suggest that the source water can either be ëlocalí (Gulf of Alaska) or very distant (tropics) . The Eclipse site seems only to get the local water . A massive dust storm originating in central Asia (Gobi) in April 2001 dumped a visible layer all over the St Elias Mountains and this layer was sampled, to provide a calibration "Asian dust event". The satellite and isotoic signatures both agreed that Gobi was the source. The PRCol record covers the Holocene and well back into the ice age. The transition is defined by a sudden ECM shift on the flanks of a more gradual O18 shift. Acknowledgements. Logan consortium consists of : Geological Survey of Canada : Jocelyne Bourgeois, Mike Demuth, David Fisher, Roy Koerner,Chris Zdanowicz, James Zheng. University of Ottawa: Ian Clarke,Raphaelle Cardyn. National Institute of Polar Research (Japan): Kumiko Goto-Azuma University of New Hampshire: Cam Wake, Kaplan Yalcin. University of Maine: Karl Kreutz, Paul Mayewski, Erich Osterberg. Arctic Institute of North America: Gerald Holdsworth. University of Washington: Eric J. Steig, Summer B. Rupper. University of Copenhagen: Dorthe Dahl-Jensen. David Fisher is the presenter but many contributed to what is a joint preliminary offering.
Multi-source remotely sensed data fusion for improving land cover classification
NASA Astrophysics Data System (ADS)
Chen, Bin; Huang, Bo; Xu, Bing
2017-02-01
Although many advances have been made in past decades, land cover classification of fine-resolution remotely sensed (RS) data integrating multiple temporal, angular, and spectral features remains limited, and the contribution of different RS features to land cover classification accuracy remains uncertain. We proposed to improve land cover classification accuracy by integrating multi-source RS features through data fusion. We further investigated the effect of different RS features on classification performance. The results of fusing Landsat-8 Operational Land Imager (OLI) data with Moderate Resolution Imaging Spectroradiometer (MODIS), China Environment 1A series (HJ-1A), and Advanced Spaceborne Thermal Emission and Reflection (ASTER) digital elevation model (DEM) data, showed that the fused data integrating temporal, spectral, angular, and topographic features achieved better land cover classification accuracy than the original RS data. Compared with the topographic feature, the temporal and angular features extracted from the fused data played more important roles in classification performance, especially those temporal features containing abundant vegetation growth information, which markedly increased the overall classification accuracy. In addition, the multispectral and hyperspectral fusion successfully discriminated detailed forest types. Our study provides a straightforward strategy for hierarchical land cover classification by making full use of available RS data. All of these methods and findings could be useful for land cover classification at both regional and global scales.
Using modern analogues to reconstruct past landcover
NASA Astrophysics Data System (ADS)
Brewer, Simon
2016-04-01
The physical cover of the earth plays an important role in the earth system. It affects the climate through feedbacks such as albedo and surface roughness, forms part of the carbon cycle as both sink and source and is both affected by and can affect human societies. Reconstructing past changes in land use and land cover helps to understand how these interactions may have changed over time, and provides important boundary conditions for paleoclimate models. Pollen assemblages, extracted from sedimentary sequences, provide one of the most abundant sources of information about past changes in land cover over the Holocene period. However, the relationship between plant cover and sedimentary pollen abundance is complex and non-linear, being affected by differential dispersal, production and taxonomic resolution. One method to correct for this and provide quantified estimates of past land cover is to calibrate modern pollen assemblages against contemporary remotely sensed estimates of land cover. Results will be presented from developing such a calibration for a set of European modern pollen samples and AVHRR-based tree cover estimates. An emphasis will be placed on the output of validation tests of the calibration, and what this indicates for the predictive skill of this approach. The calibration will then be applied to a set of pollen sequences for the European continent for the past 11,000 years, and the patterns of reconstructed land cover will be discussed.
Unique Signatures of Population III Stars in the Global 21-cm Signal
NASA Astrophysics Data System (ADS)
Mirocha, Jordan; Mebane, Richard H.; Furlanetto, Steven R.; Singal, Krishma; Trinh, Donald
2018-05-01
We investigate the effects of Population III stars on the sky-averaged 21-cm background radiation, which traces the collective emission from all sources of ultraviolet and X-ray photons before reionization is complete. While UV photons from Pop III stars can in principle shift the onset of radiative coupling of the 21-cm transition - and potentially reionization - to early times, we find that the remnants of Pop III stars are likely to have a more discernible impact on the 21-cm signal than Pop III stars themselves. The X-rays from such sources preferentially heat the IGM at early times, which elongates the epoch of reheating and results in a more gradual transition from an absorption signal to emission. This gradual heating gives rise to broad, asymmetric wings in the absorption signal, which stand in contrast to the relatively sharp, symmetric signals that arise in models treating Pop II sources only. A stronger signature of Pop III, in which the position of the absorption minimum becomes inconsistent with Pop II-only models, requires extreme star-forming events that may not be physically plausible, lending further credence to predictions of relatively high frequency absorption troughs, νmin ˜ 100 MHz. As a result, though the trough location alone may not be enough to indicate the presence of Pop III, the asymmetric wings should arise even if only a few Pop III stars form in each halo before the transition to Pop II star formation occurs, provided that the Pop III IMF is sufficiently top-heavy and at least some Pop III stars form in binaries.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Konert, G.; Van Den Brink, H.A.; Visser, W.
1991-08-01
The prolific Eastern Flank Heavy Oil province east of the South Oman Salt basin is unique because of the widespread occurrence of Precambrian source rocks from which the hydrocarbons originated. Fission-track analysis and burial studies suggest that most of these source rocks became mature and generated hydrocarbons in the Ordovician; subsequently, the source beds were uplifted and did not re-enter the oil window. Its uniqueness is also based on the all-important role played by Precambrian salt. The traps in Palaeozoic clastics were initially structured by halokinesis, and subsequently by salt dissolution. The latter process gradually removed the salt from themore » area is largely responsible for the present-day structure with palaeo-withdrawal basins inverted in present-day turtles. Present-day traps are mainly post-Late Jurassic in age, significantly post-dating the time of oil generation. Detailed field studies indicate that charge phases appear to correlate with periods of increased salt dissolution in the Late Jurassic-Early Cretaceous, Late Cretaceous, and Tertiary. Oil was probably stored in intermediate traps below and within the salt. It was gradually released upon progressive tilting of the basin flank; it migrated updip toward the basinward retreating salt edge, and subsequently (back) spilled into the stratigraphically younger traps. Also, removal of the top seal of intra-salt and sub-salt traps by salt dissolution allowed upward remigration. It follows that charge concepts in the Eastern Flank Heavy Oil province depend on defining salt-edge-related hydrocarbon release areas, rather than on kitchen modeling.« less
40 CFR 52.1168 - Certification of no sources.
Code of Federal Regulations, 2013 CFR
2013-07-01
... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) Massachusetts § 52.1168... sources are located in the Commonwealth which are covered by the following Control Techniques Guidelines...
40 CFR 52.1168 - Certification of no sources.
Code of Federal Regulations, 2011 CFR
2011-07-01
... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) Massachusetts § 52.1168... sources are located in the Commonwealth which are covered by the following Control Techniques Guidelines...
40 CFR 52.1168 - Certification of no sources.
Code of Federal Regulations, 2010 CFR
2010-07-01
... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) Massachusetts § 52.1168... sources are located in the Commonwealth which are covered by the following Control Techniques Guidelines...
40 CFR 52.1168 - Certification of no sources.
Code of Federal Regulations, 2014 CFR
2014-07-01
... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) Massachusetts § 52.1168... sources are located in the Commonwealth which are covered by the following Control Techniques Guidelines...
40 CFR 63.8390 - What parts of my plant does this subpart cover?
Code of Federal Regulations, 2010 CFR
2010-07-01
... with a design capacity equal to or greater than 9.07 Mg/hr (10 tph) of fired product will be called a... Products Manufacturing What This Subpart Covers § 63.8390 What parts of my plant does this subpart cover... manufacturing facility. (b) The existing affected source is an existing tunnel kiln with a design capacity equal...
USDA-ARS?s Scientific Manuscript database
Manure storages, and in particular those storing digested manure, are a source of ammonia (NH3) emissions. Permeable manure storage covers can reduce NH3 emissions, however performance can decline as they degrade. Thermochemical conversion of biomass through pyrolysis and steam treatment could incre...
Response of two semiarid grasslands to a second fire application
Carleton S. White; Rosemary L. Pendleton; Burton K. Pendleton
2006-01-01
Prescribed fire was used in two semiarid grasslands to reduce shrub cover, promote grass production, and reduce erosional loss that represents a potential nonÂpoint-source of sediment to degrade water quality. This study measured transported soil sediment, dynamics in soil surface microtopography, cover of the woody shrub, grass, and bare ground cover classes, and soil...
Seng, Chang Moh; Setha, To; Nealon, Joshua; Chantha, Ngan; Socheat, Doung; Nathan, Michael B
2008-12-01
Dengue in Cambodia is mainly transmitted by Aedes aegypti (L.) mosquitoes that primarily breed in large, concrete jars (> or =200 liters) used for the storage of water for domestic use. Following a preliminary risk assessment, long-lasting insecticidal netting (LN) treated with deltamethrin was incorporated into the design of the covers for these jars. Their effect on immature and adult female populations of Ae. aegypti in six villages in a peri-urban area of Cambodia were compared with populations in six nearby control villages before and for 22 weeks after distribution of the jar covers. There were significantly fewer pupae per house in intervention villages than in control villages (6.6 and 31.9, respectively, p<0.01). Fewer pupae were recovered from intervention houses than from control houses at every post-intervention assessment. Two weeks after the intervention, the average number of indoor resting female Ae. aegypti per house in the intervention villages had declined approximately three-fold, whereas in the controls there was only a slight reduction (16%). The magnitude of the difference between the two areas diminished over time, which contact bioassays confirmed was likely due to a gradual reduction of insecticidal effect of the jar covers. In the study area, insecticide-treated covers for large concrete water storage jars were efficacious for controlling Ae. aegypti in the protected water jars and with a demonstrable effect on adult densities and survival. Further studies of this targeted container strategy in Cambodia, and elsewhere, are recommended. However, improvements in technology that would extend the duration of insecticidal effectiveness of LN materials may be needed for the development of cost-effective public health applications.
2000-11-20
can be found in large numbers throughout the Yucatan , southern Mexico and Guatemala (Kumm et at. 1943, Loyola et a1. 1991, Arredondo-Jimenez et a1...material or detritus as a nutritional source as well as plant cover for shade. Anopheles yestitipennis exhibits its highest numbers during the rainy...species appears to require plant material or detritus as a nutritional source as well as plant cover for shade. Both species also have a clear seasonal
The Dependence of Characteristic Times of Gradual SEP Events on Their Associated CME Properties
NASA Astrophysics Data System (ADS)
Pan, Z. H.; Wang, C. B.; Xue, X. H.; Wang, Y. M.
It is generally believed that coronal mass ejections CMEs are the drivers of shocks that accelerate gradual solar energetic particles SEPs One might expect that the characteristics of the SEP intensity time profiles observed at 1 AU are determined by properties of the associated CMEs such as the radial speed and the angular width Recently Kahler statistically investigated the characteristic times of gradual SEP events observed from 1998-2002 and their associated coronal mass ejection properties Astrophys J 628 1014--1022 2005 Three characteristic times of gradual SEP events are determined as functions of solar source longitude 1 T 0 the time from associated CME launch to SEP onset at 1 AU 2 T R the rise time from SEP onset to the time when the SEP intensity is a factor of 2 below peak intensity and 3 T D the duration over which the SEP intensity is within a factor of 2 of the peak intensity However in his study the CME speeds and angular widths are directly taken from the LASCO CME catalog In this study we analyze the radial speeds and the angular widths of CMEs by an ice-cream cone model and re-investigate their correlationships with the characteristic times of the corresponding SEP events We find T R and T D are significantly correlated with radial speed for SEP events in the best-connected longitude range and there is no correlation between T 0 and CME radial speed and angular width which is consistent with Kahler s results On the other hand it s found that T R and T D are also have
Planning for retirement from medicine: a mixed-methods study.
Pannor Silver, Michelle; Easty, Laura K
2017-01-01
Evidence suggests there are important personal and social consequences associated with inadequate retirement planning for physicians. We evaluated whether academic physicians felt satisfied with their retirement planning, and identified obstacles to retirement planning and a set of factors to facilitate retirement planning. We applied a sequential mixed-methods research design to explore and examine factors that facilitate academic physician retirement planning using data collected from multiple sources (including 7 focus groups, an internet-based survey and 23 in-depth interviews). We examined survey results regarding retirement planning satisfaction and preferences for complete versus gradual retirement. We used thematic analysis to examine verbatim transcripts and notes from the focus groups and interviews. Survey data (response rate 51%) indicated that 10% of respondents were very satisfied with their retirement planning and 89.5% would prefer to retire gradually rather than stop work completely. Key barriers to retirement planning that emerged included poor personal financial management, rigid institutional structures and professional norms. Facilitators included financial planning resources for physicians at multiple career stages, opportunities and resources for later-career transitions and later-career mentorship support for intergenerational collaboration, and recognition of retirees. Key findings highlight perceived barriers to retirement planning at various career stages in addition to factors that can enhance physicians' retirement planning, including creating gradual and flexible retirement options, supporting ongoing discussions about financial planning and later career transitions, and fostering a culture that continues to honour and involve retirees. Medical institutions could foster innovative models for later-career transitions from medicine in ways that address physicians' needs at various career stages, support gradual transitions from practice and recognize the value of experienced, capable later-career physicians and retirees.
Planning for retirement from medicine: a mixed-methods study
Pannor Silver, Michelle; Easty, Laura K.
2017-01-01
Background: Evidence suggests there are important personal and social consequences associated with inadequate retirement planning for physicians. We evaluated whether academic physicians felt satisfied with their retirement planning, and identified obstacles to retirement planning and a set of factors to facilitate retirement planning. Methods: We applied a sequential mixed-methods research design to explore and examine factors that facilitate academic physician retirement planning using data collected from multiple sources (including 7 focus groups, an internet-based survey and 23 in-depth interviews). We examined survey results regarding retirement planning satisfaction and preferences for complete versus gradual retirement. We used thematic analysis to examine verbatim transcripts and notes from the focus groups and interviews. Results: Survey data (response rate 51%) indicated that 10% of respondents were very satisfied with their retirement planning and 89.5% would prefer to retire gradually rather than stop work completely. Key barriers to retirement planning that emerged included poor personal financial management, rigid institutional structures and professional norms. Facilitators included financial planning resources for physicians at multiple career stages, opportunities and resources for later-career transitions and later-career mentorship support for intergenerational collaboration, and recognition of retirees. Interpretation: Key findings highlight perceived barriers to retirement planning at various career stages in addition to factors that can enhance physicians' retirement planning, including creating gradual and flexible retirement options, supporting ongoing discussions about financial planning and later career transitions, and fostering a culture that continues to honour and involve retirees. Medical institutions could foster innovative models for later-career transitions from medicine in ways that address physicians' needs at various career stages, support gradual transitions from practice and recognize the value of experienced, capable later-career physicians and retirees. PMID:28401128
Nutrition Updates "Carotenoids and Health"
USDA-ARS?s Scientific Manuscript database
This symposium covered current topics in carotenoids and health, with special emphasis on healthy aging. The carotenoids covered were beta-carotene, lycopene, lutein, and beta-cryptoxanthin. Topics included the best food sources of these carotenoids, the importance of carotenoids as antioxidants an...
ERIC Educational Resources Information Center
Jewell, W. J.; Switzenbaum, M. S.
1978-01-01
Presents a literature review of agricultural wastes, covering publications of 1976-77. Some of the areas covered are: (1) water characteristics and impacts; (2) waste treatment; (3) reuse of agricultural wastes; and (4) nonpoint pollution sources. A list of 150 references is also presented. (HM)
ASTRONAUTICS INFORMATION. ABSTRACTS, VOL. V, NO. 3. Abstracts 5,201- 5,330
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hardgrove, B.J.; Warren, F.L. comps.
1962-03-01
Abstracts of astronautics information covering the period March 1962 are presented. The 129 abstracts cover the subject of spaceflight and applicable data and techniques. Author, subject, and source indexes are included. (M.C.G.)
[Characteristics of chemical pollution of snow cover in Aktobe areas].
Iskakov, A Zh
2010-01-01
The paper gives data on the nature of snow cover pollution in the urbanized areas in relation to the remoteness from the basic sources of ambient air pollution. The total snow content of carcinogens has been estimated.
Takahashi, Kazunori
2012-08-01
A radiofrequency (rf) antenna for helicon plasma thruster experiments is developed and tested using a permanent magnets helicon plasma source immersed in a vacuum chamber. A magnetic nozzle is provided by permanent magnets arrays and an argon plasma is produced by a 13.56 MHz radiofrequency helicon-wave or inductively-coupled discharge. A parasitic discharge outside the source tube is successfully suppressed by covering the rf antenna with a ceramic ring and a grounded shield; a decrease in the ion saturation current of a Langmuir probe located outside the source tube is observed and the ion saturation current on axis increases simultaneously, compared with the case of a standard uncovered rf antenna. It is also demonstrated that the covered antenna can yield stable operation of the source.
JPRS Report, Near East & South Asia, Bangladesh
1991-08-13
General Secretary of She however alleged that Avhi circle, the accused killers of the DUCSU, a competently source close to the high Dr. Milon are now...prior to the February 27 parliamentary elections were not Milon is now indulging in hooliganism on the campuses yet materialised. Even the 10-point...result, unemployment has been gradually taking a very serious shape, she added. Replying a question he firmly said unless the killers of Dr. Milon who were
Un regard international sur la sécurité nucléaire
NASA Astrophysics Data System (ADS)
Birkhofer, Adolf
2002-10-01
Safety has always been an important objective in nuclear technology. Starting with a set of sound physical principles and prudent design approaches, safety concepts have gradually been refined and cover now a wide range of provisions related to design, quality and operation. Research, the evaluation of operating experiences and probabilistic risk assessments constitute an essential basis and international co-operation plays a significant role in that context. Concerning future developments a major objective for new reactor concepts, such as the EPR, is to practically exclude a severe core damage accident with large scale consequences outside the plant. To cite this article: A. Birkhofer, C. R. Physique 3 (2002) 1059-1065.
Mechanisms of Cardiopulmonary Adaptation to Microgravity. Part 1
NASA Technical Reports Server (NTRS)
1997-01-01
Session TA1 includes short reports covering: (1) Indices of Baroreceptor Reflex Sensitivity: The Use in Rehabilitation Medicine and Space Cardiology; (2) +Gz and +Gx Tolerance of Healthy Persons of Non-Flying Trades at Primary Selection of the Centrifuge; (3) Effect of Dry Immersion on Calf Blood Supply During Sustained Contraction and Upright Exercise in Man; (4) Cardiovascular and Valsalva Responses during Parabolic flight; (5) An Analysis of the Cardiovascular Responses under Hyper- and Hypo-Gravity Environments using a Mathematical model; (6) Effect of Very Gradual Onset Rate +Gz Exposures on the Cardiovascular System; and (7) NASA Specialized Center of Research and Training (NSCORT) in Integrated Physiology: Mechanisms of Physiological Adaptations to Microgravity.
Schachter, L; Stiebing, K E; Dobrescu, S
2009-01-01
The influence of metal-dielectric (MD) layers (MD structures) inserted into the plasma chamber of an electron cyclotron resonance ion source (ECRIS) onto the production of electron bremsstrahlung radiation has been studied in a series of dedicated experiments at the 14 GHz ECRIS of the Institut für Kernphysik der Universität Frankfurt. The IKF-ECRIS was equipped with a MD liner, covering the inner walls of the plasma chamber, and a MD electrode, covering the plasma-facing side of the extraction electrode. On the basis of similar extracted currents of highly charged ions, significantly reduced yields of bremsstrahlung radiation for the "MD source" as compared to the standard (stainless steel) source have been measured and can be explained by the significantly better plasma confinement in a MD source as compared to an "all stainless steel" ECRIS.
Regional land cover characterization using Landsat thematic mapper data and ancillary data sources
Vogelmann, James E.; Sohl, Terry L.; Campbell, P.V.; Shaw, D.M.; ,
1998-01-01
As part of the activities of the Multi-Resolution Land Characteristics (MRLC) Interagency Consortium, an intermediate-scale land cover data set is being generated for the conterminous United States. This effort is being conducted on a region-by-region basis using U.S. Standard Federal Regions. To date, land cover data sets have been generated for Federal Regions 3 (Pennsylvania, West Virginia, Virginia, Maryland, and Delaware) and 2 (New York and New Jersey). Classification work is currently under way in Federal Region 4 (the southeastern United States), and land cover mapping activities have been started in Federal Regions 5 (the Great Lakes region) and 1 (New England). It is anticipated that a land cover data set for the conterminous United States will be completed by the end of 1999. A standard land cover classification legend is used, which is analogous to and compatible with other classification schemes. The primary MRLC regional classification scheme contains 23 land cover classes.The primary source of data for the project is the Landsat thematic mapper (TM) sensor. For each region, TM scenes representing both leaf-on and leaf-off conditions are acquired, preprocessed, and georeferenced to MRLC specifications. Mosaicked data are clustered using unsupervised classification, and individual clusters are labeled using aerial photographs. Individual clusters that represent more than one land cover unit are split using spatial modeling with multiple ancillary spatial data layers (most notably, digital elevation model, population, land use and land cover, and wetlands information). This approach yields regional land cover information suitable for a wide array of applications, including landscape metric analyses, land management, land cover change studies, and nutrient and pesticide runoff modeling.
Printing and Publishing Monitoring Information
Stationary source emissions monitoring is required to demonstrate that a source is meeting the requirements in Federal or state rules. This page covers monitoring information specific to the printing and publishing industry.
Climate Change for Agriculture, Forest Cover and 3d Urban Models
NASA Astrophysics Data System (ADS)
Kapoor, M.; Bassir, D.
2014-11-01
This research demonstrates the important role of the remote sensing in finding out the different parameters behind the agricultural crop change, forest cover and urban 3D models. Standalone software is developed to view and analysis the different factors effecting the change in crop productions. Open-source libraries from the Open Source Geospatial Foundation have been used for the development of the shape-file viewer. Software can be used to get the attribute information, scale, zoom in/out and pan the shapefiles. Environmental changes due to pollution and population that are increasing the urbanisation and decreasing the forest cover on the earth. Satellite imagery such as Landsat 5(1984) to Landsat TRIS/8 (2014), Landsat Data Continuity Mission (LDCM) and NDVI are used to analyse the different parameters that are effecting the agricultural crop production change and forest change. It is advisable for the development of good quality of NDVI and forest cover maps to use data collected from the same processing methods for the complete region. Management practices have been developed from the analysed data for the betterment of the crop and saving the forest cover
Archaeology: A Student's Guide to Reference Sources.
ERIC Educational Resources Information Center
Desautels, Almuth, Comp.
This bibliography lists reference sources for research in archaeology. It is arranged in sections by type of reference source with subsections for general works and works covering specific areas. Categorized are handbooks; directories, biographies, and museums; encyclopedias; dictionaries; atlases; guides, manuals, and surveys; bibliographies; and…
NASA Astrophysics Data System (ADS)
Aharonian, F. A.; Akhperjanian, A. G.; Beilicke, M.; Bernloehr, K.; Bojahr, H.; Bolz, O.; Boerst, H.; Coarasa, T.; Contreras, J. L.; Cortina, J.; Denninghoff, S.; Fonseca, V.; Girma, M.; Goetting, N.; Heinzelmann, G.; Hermann, G.; Heusler, A.; Hofmann, W.; Horns, D.; Jung, I.; Kankanyan, R.; Kestel, M.; Kettler, J.; Kohnle, A.; Konopelko, A.; Kornmeyer, H.; Kranich, D.; Krawczynski, H.; Lampeitl, H.; Lopez, M.; Lorenz, E.; Lucarelli, F.; Mang, O.; Meyer, H.; Mirzoyan, R.; Moralejo, A.; Ona, E.; Panter, M.; Plyasheshnikov, A.; Puehlhofer, G.; Rauterberg, G.; Reyes, R.; Rhode, W.; Ripken, J.; Roehring, A.; Rowell, G. P.; Sahakian, V.; Samorski, M.; Schilling, M.; Siems, M.; Sobzynska, D.; Stamm, W.; Tluczykont, M.; Voelk, H. J.; Wiedner, C. A.; Wittek, W.
2002-12-01
Using the HEGRA system of imaging atmospheric Cherenkov telescopes, one quarter of the Galactic plane (-2o < l < 85o) was surveyed for TeV gamma-ray emission from point sources and moderately extended sources (φ <= 0.8o). The region covered includes 86 known pulsars (PSR), 63 known supernova remnants (SNR) and nine GeV sources, representing a significant fraction of the known populations. No evidence for emission of TeV gamma radiation was detected, and upper limits range from 0.15 Crab units up to several Crab units, depending on the observation time and zenith angles covered. The ensemble sums over selected SNR and pulsar subsamples and over the GeV-sources yield no indication of emission from these potential sources. The upper limit for the SNR population is 6.7% of the Crab flux and for the pulsar ensemble is 3.6% of the Crab flux.
GENERATING HIGH QUALITY IMPERVIOUS COVER DATA
Nonpoint source pollution (NPS) from urban/ suburban areas is rapidly increasing as the population increases in the United States. Research in recent years has consistently shown a strong relationship between the percentage of impervious cover in a drainage basin and the health...
Method and apparatus for recovering a gas from a gas hydrate located on the ocean floor
Wyatt, Douglas E.
2001-01-01
A method and apparatus for recovering a gas from a gas hydrate on the ocean floor includes a flexible cover, a plurality of steerable base members secured to the cover, and a steerable mining module. A suitable source for inflating the cover over the gas hydrate deposit is provided. The mining module, positioned on the gas hydrate deposit, is preferably connected to the cover by a control cable. A gas retrieval conduit or hose extends upwardly from the cover to be connected to a support ship on the ocean surface.
Land Cover Characterization Program
,
1997-01-01
(2) identify sources, develop procedures, and organize partners to deliver data and information to meet user requirements. The LCCP builds on the heritage and success of previous USGS land use and land cover programs and projects. It will be compatible with current concepts of government operations, the changing needs of the land use and land cover data users, and the technological tools with which the data are applied.
A radio source occultation experiment with comet Austin 1982g, with unusual results
NASA Technical Reports Server (NTRS)
De Pater, I.; Ip, W.-H.
1984-01-01
A radio source occultation by comet Austin 1982g was observed on September 15-16, 1982. A change in the apparent position of 1242 + 41 by 1.3 arcsec occurred when the source was 220,000 km away from the cometary ion tail. If this change was due to refraction by the cometary plasma, it indicates an electron density of the plasma of about 10,000/cu cm. When the radio source was on the other side of the plasma tail, at a distance of 230,000 km, the position angle of the electric vector of the radio source changed gradually over about 140 deg within two hours. This observation cannot be explained in terms of ionospheric Faraday rotation, and results from either an intrinsic change in the radio source or Faraday rotation in the cometary plasma due to a change in the direction and/or strength of the magnetic field. In the latter case, the cometary coma must have an electron density and a magnetic field strength orders of magnitude larger than current theories predict.
NASA Astrophysics Data System (ADS)
Pan, L., Sr.; Ren, J.
2017-12-01
The South China Sea (SCS) is one of the largest marginal sea on southeast Asia continental margin, developed Paleogene extension-rifting continental margin system which is rare in the world and preserving many deformed characterizes of this kind system. With the investigation of the SCS, guiding by the development of tectonics and geo-physics, especially the development of tectonics and the high quality seismic data based on the development of geo-physics, people gradually accept that the northern margin of the SCS has some detachment basin characterizes. After researching the northern margin of the SCS, we come up with lithosphere profiles across the shelf, slope and deep sea basin in the northeast of the SCS to confirm the tectonic style of ocean-continental transition and the property of the detachment fault. Furthermore, we describe the outline of large detachment basins at northern SCS. Based on the large number of high-quality 2D and 3D deep seismic profile(TWT,10s), drilling and logging data, combined with domestic and international relevant researches, using basin dynamics and tectono-stratigraphy theory, techniques and methods of geology and geophysics, qualitative and quantitative, we describe the formation of the detachment basin and calculate the fault activity rate, stretching factor and settlement. According to the research, we propose that there is a giant and complete detachment basin system in the northern SCS and suggest three conclusions. First of all, the detachment basin system can be divided into three domains: proximal domain covering the Yangjiang Sag, Shenhu uplift and part of Shunde Sag, necking zone covering part of the Shunde Sag and Heshan Sag, distal domain covering most part of Heshan Sag. Second, the difference of the stretching factor is observed along the three domains of the detachment basin system. The factor of the proximal domain is the minimum among them. On the other side, the distal domain is the maximum among them. This phenomenon can be concluded as the factor is gradually increasing from the continent to the ocean. Third, the development of detachment basin is episodic which can be divided into two stages approximately: the rifting and thermal subsidence.
Spatial Dmbs Architecture for a Free and Open Source Bim
NASA Astrophysics Data System (ADS)
Logothetis, S.; Valari, E.; Karachaliou, E.; Stylianidis, E.
2017-08-01
Recent research on the field of Building Information Modelling (BIM) technology, revealed that except of a few, accessible and free BIM viewers there is a lack of Free & Open Source Software (FOSS) BIM software for the complete BIM process. With this in mind and considering BIM as the technological advancement of Computer-Aided Design (CAD) systems, the current work proposes the use of a FOSS CAD software in order to extend its capabilities and transform it gradually into a FOSS BIM platform. Towards this undertaking, a first approach on developing a spatial Database Management System (DBMS) able to store, organize and manage the overall amount of information within a single application, is presented.
NASA Astrophysics Data System (ADS)
Stockli, Martin P.; Welton, Robert F.; Han, Baoxi
2018-05-01
The Spallation Neutron Source operates reliably at 1.2 MW and will gradually ramp to 1.4 MW. This paper briefly recalls some of the struggles when the unprecedented project was started and ramped to 1 MW over a 3½ year period. This was challenging, especially for the H- ion source and the low-energy beam transport system, which make up the H- injector. It took several more years to push the H- injector to the 1.4 MW requirements, and even longer to reach close to 100% injector availability. An additional breakthrough was the carefully staged, successful extension of the H- source service cycle so that disruptive source changes became rare events. More than 7 A.h of extracted H- ions have been demonstrated with a single source without maintenance, more than twice the single-source quantity of ions produced by any other high-current H- accelerator facility. Achieving the 1.4 MW requirements with close to 100% availability and record-breaking source service cycles were the basis for the 2017 Brightness Award.
Urban base flow with low impact development
Bhaskar, Aditi; Hogan, Dianna M.; Archfield, Stacey A.
2016-01-01
A novel form of urbanization, low impact development (LID), aims to engineer systems that replicate natural hydrologic functioning, in part by infiltrating stormwater close to the impervious surfaces that generate it. We sought to statistically evaluate changes in a base flow regime because of urbanization with LID, specifically changes in base flow magnitude, seasonality, and rate of change. We used a case study watershed in Clarksburg, Maryland, in which streamflow was monitored during whole-watershed urbanization from forest and agricultural to suburban residential development using LID. The 1.11-km2 watershed contains 73 infiltration-focused stormwater facilities, including bioretention facilities, dry wells, and dry swales. We examined annual and monthly flow during and after urbanization (2004–2014) and compared alterations to nearby forested and urban control watersheds. We show that total streamflow and base flow increased in the LID watershed during urbanization as compared with control watersheds. The LID watershed had more gradual storm recessions after urbanization and attenuated seasonality in base flow. These flow regime changes may be because of a reduction in evapotranspiration because of the overall decrease in vegetative cover with urbanization and the increase in point sources of recharge. Precipitation that may once have infiltrated soil, been stored in soil moisture to be eventually transpired in a forested landscape, may now be recharged and become base flow. The transfer of evapotranspiration to base flow is an unintended consequence to the water balance of LID.
Alslaibi, Tamer M; Abunada, Ziyad; Abu Amr, Salem S; Abustan, Ismail
2017-09-22
Landfills are one of the main point sources of groundwater pollution. This research mainly aims to assess the risk of nitrate [Formula: see text] transport from the unlined landfill to subsurface layers and groundwater using experimental results and the SESOIL model. Samples from 12 groundwater wells downstream of the landfill were collected and analyzed in 2008, 21 years after the landfill construction. The average [Formula: see text] concentration in the wells was 54 mg/L, slightly higher than the World Health Organization ([Formula: see text] 50 mg/L) standards. SESOIL model was used to predict the [Formula: see text] concentration at the bottom of the unsaturated zone. Results indicated that the current mean [Formula: see text] concentration at the bottom of the unsaturated zone is 75 mg/L. the model predicted that the level of NO 3 will increased up to 325 mg/L within 30 years. Accordingly, the [Formula: see text] concentration in groundwater wells near the landfill area is expected to gradually increase with time. Although the current risk associated with the [Formula: see text] level might not be harm to adults, however, it might pose severe risks to both adults and infants in the near future due to [Formula: see text] leaching. Urgent mitigation measures such as final cell cover (cap), lining system and vertical expansion should be considered at the landfill to protect the public health in the area.
NASA Astrophysics Data System (ADS)
Schurr, B.; Hainzl, S.; Bedford, J. R.; Hoechner, A.; Wang, R.; Zhang, Y.; Oncken, O.; Palo, M.; Bartsch, M.; Moreno, M.; Tilmann, F. J.; Dahm, T.; Victor, P.; Barrientos, S. E.; Vilotte, J. P.
2014-12-01
On April 1st, 2014, Northern Chile, was struck by a magnitude 8.1 earthquake near the city of Iquique following a protracted series of foreshocks. The earthquake occurred within a seismic gap left behind by two great earthquakes devastating the northern Chilean and southern Peruvian coast about 140 years ago in 1868 and 1877. This segment, about 500 km long, was the only one along the Chilean subduction zone that has not ruptured within the last century. The Integrated Plate boundary Observatory Chile (IPOC) monitored the entire sequence of events, providing unprecedented resolution of the build-up to the main event and its rupture evolution. We analyzed the entire seismicity in this section of the subduction zone since 2007. The offshore rupture region of the Iquique event has been more or less continuously seismically active within our observation period. This is in contrast to the segments to the north and south, which are still unruptured and seismically quiet. Starting in July 2013, three foreshock clusters with increasingly larger magnitudes occurred within the future rupture area. The largest Mw 6.7 foreshock, two weeks before the mainshock, had a source mechanism distinctively different from the mainshock and with a centroid depth of only 9 km probably occurred in the upper plate. The Iquique mainshock initiated then at the northern end of the foreshock zone, inside a region of intermediate interseismic locking. Comparing the foreshock distribution to the long term deformation history of the margin, we find that the area exhibits a high gradient of locking from weakly locked updip to fully locked downdip. Mapping the b-value of the foreshocks indicates significantly lower b-values in the source area compared to all other regions where the b-value can be resolved. Importantly, a gradual drop of the b-value from about 0.75 to below 0.6 is observed in the source region within the three years before the Iquique earthquake. This has only been reversed within the last days of the foreshock sequence. We conclude that gradual weakening of the central part of the seismic gap accentuated by the foreshock activity in a zone of intermediate seismic coupling was instrumental in causing final failure.
Silvestri, Stefano
2009-01-01
In Italy during the last three decades important changes in employment have occurred. During the '70s, thanks to a variety of factors, the hygiene conditions of work have undergone a process of slow, but gradual improvement, which has not been arrested during the following decades. New legislation, partly deriving from European directives, has been introduced, and processes of outsourcing have moved the most burdensome and pollutants industrial productions to developing countries. Nevertheless, the estimates of the number of exposed (or even potentially so) workers, to carcinogens remain quite high. Currently, in absence of the planned National Information System on Prevention, it is impossible to estimate in how many and which workplaces primary prevention plans and facilities have been already installed. This paper aims to describe the situation related to most occupationally diffused carcinogenic agents: asbestos, wood and crystalline silica dusts, each one for its specificity. It also describes the innovations introduced by the most recent legislation, in particular with regard to the asbestos risk control. Finally, it stresses the need for a reform of the insurance premiums in order to introduce a mechanism for rewarding those employers who implement primary prevention facilities and penalizing those who don't. The economic advantages should gradually cover the cost of risk control technology.
NASA Astrophysics Data System (ADS)
Dostálek, Jiří; Frantík, Tomáš
2012-04-01
Dry grasslands are one of the most species rich and endangered types of vegetation in Europe. In the Czech Republic, dry grasslands are mainly of anthropogenic origin and were formed as a result of grazing after the clear-cutting of thermophilous oak woods. Gradual changes in the farming landscape throughout the 20th century, particularly in the 1960s, resulted in the abandonment of the relatively infertile habitats of dry grasslands. After abandonment, dry grasslands decline and degrade due to the gradual overgrowth of woody species and expansion of perennial tall grasses. In the year 2000, a grazing management program was introduced in the protected areas within the territory of Prague City to maintain the species diversity of dry grasslands. The responses of the expansive grass species, Arrhenatherum elatius L. and multiple woody species (especially, Prunus spinosa L.) to differences in grazing periods were monitored for over a decade . Grazing in spring through the end of June had the greatest impact on the reduction of A. elatius and woody species. Grazing in the height of summer through autumn did not reduce the cover of these plants, and may support the prosperity of both A. elatius and the woody species due to higher levels of nutrients.
Forecasting land cover change impacts on drinking water treatment costs in Minneapolis, Minnesota
Source protection is a critical aspect of drinking water treatment. The benefits of protecting source water quality in reducing drinking water treatment costs are clear. However, forecasting the impacts of environmental change on source water quality and its potential to influenc...
40 CFR 63.7490 - What is the affected source of this subpart?
Code of Federal Regulations, 2010 CFR
2010-07-01
... PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Industrial, Commercial, and Institutional Boilers and Process Heaters What This Subpart Covers § 63.7490 What is the affected source of this...
Teaching Discrete Mathematics Entirely from Primary Historical Sources
ERIC Educational Resources Information Center
Barnett, Janet Heine; Bezhanishvili, Guram; Lodder, Jerry; Pengelley, David
2016-01-01
We describe teaching an introductory discrete mathematics course entirely from student projects based on primary historical sources. We present case studies of four projects that cover the content of a one-semester course, and mention various other courses that we have taught with primary source projects.
The influence of lithology on surface water sources
Understanding the temporal and spatial variability of surface water sources within a basin is vital to our ability to manage the impacts of climate variability and land cover change. Water stable isotopes can be used as a tool to determine geographic and seasonal sources of water...
Evaluation of forest cover estimates for Haiti using supervised classification of Landsat data
NASA Astrophysics Data System (ADS)
Churches, Christopher E.; Wampler, Peter J.; Sun, Wanxiao; Smith, Andrew J.
2014-08-01
This study uses 2010-2011 Landsat Thematic Mapper (TM) imagery to estimate total forested area in Haiti. The thematic map was generated using radiometric normalization of digital numbers by a modified normalization method utilizing pseudo-invariant polygons (PIPs), followed by supervised classification of the mosaicked image using the Food and Agriculture Organization (FAO) of the United Nations Land Cover Classification System. Classification results were compared to other sources of land-cover data produced for similar years, with an emphasis on the statistics presented by the FAO. Three global land cover datasets (GLC2000, Globcover, 2009, and MODIS MCD12Q1), and a national-scale dataset (a land cover analysis by Haitian National Centre for Geospatial Information (CNIGS)) were reclassified and compared. According to our classification, approximately 32.3% of Haiti's total land area was tree covered in 2010-2011. This result was confirmed using an error-adjusted area estimator, which predicted a tree covered area of 32.4%. Standardization to the FAO's forest cover class definition reduces the amount of tree cover of our supervised classification to 29.4%. This result was greater than the reported FAO value of 4% and the value for the recoded GLC2000 dataset of 7.0%, but is comparable to values for three other recoded datasets: MCD12Q1 (21.1%), Globcover (2009) (26.9%), and CNIGS (19.5%). We propose that at coarse resolutions, the segmented and patchy nature of Haiti's forests resulted in a systematic underestimation of the extent of forest cover. It appears the best explanation for the significant difference between our results, FAO statistics, and compared datasets is the accuracy of the data sources and the resolution of the imagery used for land cover analyses. Analysis of recoded global datasets and results from this study suggest a strong linear relationship (R2 = 0.996 for tree cover) between spatial resolution and land cover estimates.
Development of a global land cover characteristics database and IGBP DISCover from 1 km AVHRR data
Loveland, Thomas R.; Reed, B.C.; Brown, Jesslyn F.; Ohlen, D.O.; Zhu, Z.; Yang, L.; Merchant, J.W.
2000-01-01
Researchers from the U.S. Geological Survey, University of Nebraska-Lincoln and the European Commission's Joint Research Centre, Ispra, Italy produced a 1 km resolution global land cover characteristics database for use in a wide range of continental-to global-scale environmental studies. This database provides a unique view of the broad patterns of the biogeographical and ecoclimatic diversity of the global land surface, and presents a detailed interpretation of the extent of human development. The project was carried out as an International Geosphere-Biosphere Programme, Data and Information Systems (IGBP-DIS) initiative. The IGBP DISCover global land cover product is an integral component of the global land cover database. DISCover includes 17 general land cover classes defined to meet the needs of IGBP core science projects. A formal accuracy assessment of the DISCover data layer will be completed in 1998. The 1 km global land cover database was developed through a continent-by-continent unsupervised classification of 1 km monthly Advanced Very High Resolution Radiometer (AVHRR) Normalized Difference Vegetation Index (NDVI) composites covering 1992-1993. Extensive post-classification stratification was necessary to resolve spectral/temporal confusion between disparate land cover types. The complete global database consists of 961 seasonal land cover regions that capture patterns of land cover, seasonality and relative primary productivity. The seasonal land cover regions were aggregated to produce seven separate land cover data sets used for global environmental modelling and assessment. The data sets include IGBP DISCover, U.S. Geological Survey Anderson System, Simple Biosphere Model, Simple Biosphere Model 2, Biosphere-Atmosphere Transfer Scheme, Olson Ecosystems and Running Global Remote Sensing Land Cover. The database also includes all digital sources that were used in the classification. The complete database can be sourced from the website: http://edcwww.cr.usgs.gov/landdaac/glcc/glcc.html.
40 CFR 424.26 - Pretreatment standards for new sources.
Code of Federal Regulations, 2014 CFR
2014-07-01
... GUIDELINES AND STANDARDS FERROALLOY MANUFACTURING POINT SOURCE CATEGORY Covered Electric Furnaces and Other... a publicly owned treatment works must comply with 40 CFR part 403. [60 FR 33957, June 29, 1995] ...
40 CFR 424.26 - Pretreatment standards for new sources.
Code of Federal Regulations, 2012 CFR
2012-07-01
... GUIDELINES AND STANDARDS FERROALLOY MANUFACTURING POINT SOURCE CATEGORY Covered Electric Furnaces and Other... a publicly owned treatment works must comply with 40 CFR part 403. [60 FR 33957, June 29, 1995] ...
40 CFR 424.26 - Pretreatment standards for new sources.
Code of Federal Regulations, 2010 CFR
2010-07-01
... GUIDELINES AND STANDARDS FERROALLOY MANUFACTURING POINT SOURCE CATEGORY Covered Electric Furnaces and Other... a publicly owned treatment works must comply with 40 CFR part 403. [60 FR 33957, June 29, 1995] ...
40 CFR 424.26 - Pretreatment standards for new sources.
Code of Federal Regulations, 2013 CFR
2013-07-01
... GUIDELINES AND STANDARDS FERROALLOY MANUFACTURING POINT SOURCE CATEGORY Covered Electric Furnaces and Other... a publicly owned treatment works must comply with 40 CFR part 403. [60 FR 33957, June 29, 1995] ...
40 CFR 424.26 - Pretreatment standards for new sources.
Code of Federal Regulations, 2011 CFR
2011-07-01
... GUIDELINES AND STANDARDS FERROALLOY MANUFACTURING POINT SOURCE CATEGORY Covered Electric Furnaces and Other... a publicly owned treatment works must comply with 40 CFR part 403. [60 FR 33957, June 29, 1995] ...
Iwata, Masaki; Ohno, Yoshikazu; Otaki, Joji M.
2014-01-01
Butterfly wings are covered with regularly arranged single-colored scales that are formed at the pupal stage. Understanding pupal wing development is therefore crucial to understand wing color pattern formation. Here, we successfully employed real-time in vivo imaging techniques to observe pupal hindwing development over time in the blue pansy butterfly, Junonia orithya. A transparent sheet of epithelial cells that were not yet regularly arranged was observed immediately after pupation. Bright-field imaging and autofluorescent imaging revealed free-moving hemocytes and tracheal branches of a crinoid-like structure underneath the epithelium. The wing tissue gradually became gray-white, epithelial cells were arranged regularly, and hemocytes disappeared, except in the bordering lacuna, after which scales grew. The dynamics of the epithelial cells and scale growth were also confirmed by fluorescent imaging. Fluorescent in vivo staining further revealed that these cells harbored many mitochondria at the surface of the epithelium. Organizing centers for the border symmetry system were apparent immediately after pupation, exhibiting a relatively dark optical character following treatment with fluorescent dyes, as well as in autofluorescent images. The wing tissue exhibited slow and low-frequency contraction pulses with a cycle of approximately 10 to 20 minutes, mainly occurring at 2 to 3 days postpupation. The pulses gradually became slower and weaker and eventually stopped. The wing tissue area became larger after contraction, which also coincided with an increase in the autofluorescence intensity that might have been caused by scale growth. Examination of the pattern of color development revealed that the black pigment was first deposited in patches in the central areas of an eyespot black ring and a parafocal element. These results of live in vivo imaging that covered wide wing area for a long time can serve as a foundation for studying the cellular dynamics of living wing tissues in butterflies. PMID:24586829
Iwata, Masaki; Ohno, Yoshikazu; Otaki, Joji M
2014-01-01
Butterfly wings are covered with regularly arranged single-colored scales that are formed at the pupal stage. Understanding pupal wing development is therefore crucial to understand wing color pattern formation. Here, we successfully employed real-time in vivo imaging techniques to observe pupal hindwing development over time in the blue pansy butterfly, Junonia orithya. A transparent sheet of epithelial cells that were not yet regularly arranged was observed immediately after pupation. Bright-field imaging and autofluorescent imaging revealed free-moving hemocytes and tracheal branches of a crinoid-like structure underneath the epithelium. The wing tissue gradually became gray-white, epithelial cells were arranged regularly, and hemocytes disappeared, except in the bordering lacuna, after which scales grew. The dynamics of the epithelial cells and scale growth were also confirmed by fluorescent imaging. Fluorescent in vivo staining further revealed that these cells harbored many mitochondria at the surface of the epithelium. Organizing centers for the border symmetry system were apparent immediately after pupation, exhibiting a relatively dark optical character following treatment with fluorescent dyes, as well as in autofluorescent images. The wing tissue exhibited slow and low-frequency contraction pulses with a cycle of approximately 10 to 20 minutes, mainly occurring at 2 to 3 days postpupation. The pulses gradually became slower and weaker and eventually stopped. The wing tissue area became larger after contraction, which also coincided with an increase in the autofluorescence intensity that might have been caused by scale growth. Examination of the pattern of color development revealed that the black pigment was first deposited in patches in the central areas of an eyespot black ring and a parafocal element. These results of live in vivo imaging that covered wide wing area for a long time can serve as a foundation for studying the cellular dynamics of living wing tissues in butterflies.
NASA Astrophysics Data System (ADS)
Rover, J.; Goldhaber, M. B.; Holen, C.; Dittmeier, R.; Wika, S.; Steinwand, D.; Dahal, D.; Tolk, B.; Quenzer, R.; Nelson, K.; Wylie, B. K.; Coan, M.
2015-12-01
Multi-year land cover mapping from remotely sensed data poses challenges. Producing land cover products at spatial and temporal scales required for assessing longer-term trends in land cover change are typically a resource-limited process. A recently developed approach utilizes open source software libraries to automatically generate datasets, decision tree classifications, and data products while requiring minimal user interaction. Users are only required to supply coordinates for an area of interest, land cover from an existing source such as National Land Cover Database and percent slope from a digital terrain model for the same area of interest, two target acquisition year-day windows, and the years of interest between 1984 and present. The algorithm queries the Landsat archive for Landsat data intersecting the area and dates of interest. Cloud-free pixels meeting the user's criteria are mosaicked to create composite images for training the classifiers and applying the classifiers. Stratification of training data is determined by the user and redefined during an iterative process of reviewing classifiers and resulting predictions. The algorithm outputs include yearly land cover raster format data, graphics, and supporting databases for further analysis. Additional analytical tools are also incorporated into the automated land cover system and enable statistical analysis after data are generated. Applications tested include the impact of land cover change and water permanence. For example, land cover conversions in areas where shrubland and grassland were replaced by shale oil pads during hydrofracking of the Bakken Formation were quantified. Analytical analysis of spatial and temporal changes in surface water included identifying wetlands in the Prairie Pothole Region of North Dakota with potential connectivity to ground water, indicating subsurface permeability and geochemistry.
AMI-LA observations of the SuperCLASS supercluster
NASA Astrophysics Data System (ADS)
Riseley, C. J.; Grainge, K. J. B.; Perrott, Y. C.; Scaife, A. M. M.; Battye, R. A.; Beswick, R. J.; Birkinshaw, M.; Brown, M. L.; Casey, C. M.; Demetroullas, C.; Hales, C. A.; Harrison, I.; Hung, C.-L.; Jackson, N. J.; Muxlow, T.; Watson, B.; Cantwell, T. M.; Carey, S. H.; Elwood, P. J.; Hickish, J.; Jin, T. Z.; Razavi-Ghods, N.; Scott, P. F.; Titterington, D. J.
2018-03-01
We present a deep survey of the Super-Cluster Assisted Shear Survey (SuperCLASS) supercluster - a region of sky known to contain five Abell clusters at redshift z ˜ 0.2 - performed using the Arcminute Microkelvin Imager (AMI) Large Array (LA) at 15.5 GHz. Our survey covers an area of approximately 0.9 deg2. We achieve a nominal sensitivity of 32.0 μJy beam-1 towards the field centre, finding 80 sources above a 5σ threshold. We derive the radio colour-colour distribution for sources common to three surveys that cover the field and identify three sources with strongly curved spectra - a high-frequency-peaked source and two GHz-peaked-spectrum sources. The differential source count (i) agrees well with previous deep radio source counts, (ii) exhibits no evidence of an emerging population of star-forming galaxies, down to a limit of 0.24 mJy, and (iii) disagrees with some models of the 15 GHz source population. However, our source count is in agreement with recent work that provides an analytical correction to the source count from the Square Kilometre Array Design Study (SKADS) Simulated Sky, supporting the suggestion that this discrepancy is caused by an abundance of flat-spectrum galaxy cores as yet not included in source population models.
Assessing winter cover crop nutrient uptake efficiency using a water quality simulation model
NASA Astrophysics Data System (ADS)
Yeo, I.-Y.; Lee, S.; Sadeghi, A. M.; Beeson, P. C.; Hively, W. D.; McCarty, G. W.; Lang, M. W.
2013-11-01
Winter cover crops are an effective conservation management practice with potential to improve water quality. Throughout the Chesapeake Bay Watershed (CBW), which is located in the Mid-Atlantic US, winter cover crop use has been emphasized and federal and state cost-share programs are available to farmers to subsidize the cost of winter cover crop establishment. The objective of this study was to assess the long-term effect of planting winter cover crops at the watershed scale and to identify critical source areas of high nitrate export. A physically-based watershed simulation model, Soil and Water Assessment Tool (SWAT), was calibrated and validated using water quality monitoring data and satellite-based estimates of winter cover crop species performance to simulate hydrological processes and nutrient cycling over the period of 1991-2000. Multiple scenarios were developed to obtain baseline information on nitrate loading without winter cover crops planted and to investigate how nitrate loading could change with different winter cover crop planting scenarios, including different species, planting times, and implementation areas. The results indicate that winter cover crops had a negligible impact on water budget, but significantly reduced nitrate leaching to groundwater and delivery to the waterways. Without winter cover crops, annual nitrate loading was approximately 14 kg ha-1, but it decreased to 4.6-10.1 kg ha-1 with winter cover crops resulting in a reduction rate of 27-67% at the watershed scale. Rye was most effective, with a potential to reduce nitrate leaching by up to 93% with early planting at the field scale. Early planting of winter cover crops (~30 days of additional growing days) was crucial, as it lowered nitrate export by an additional ~2 kg ha-1 when compared to late planting scenarios. The effectiveness of cover cropping increased with increasing extent of winter cover crop implementation. Agricultural fields with well-drained soils and those that were more frequently used to grow corn had a higher potential for nitrate leaching and export to the waterways. This study supports the effective implement of winter cover crop programs, in part by helping to target critical pollution source areas for winter cover crop implementation.
The Greek-Turkish Rapprochement Process, 1999-2004: Paradigm Shift or Epi-phenomenon
2004-12-01
ke y U ni te d K in gd om T ot al N A T O E ur op e C an ad a U ni te d S ta te s T ot al N or th A m er ic a To ta l N A T O 1980 1990 2001... C . METHODOLOGY AND SOURCES...................................................... 4 D. SIGNIFICANCE...13 b. Gradual Reciprocation in Tension Reduction .......... 14 C . STATES’ COOPERATION AND
1987-09-01
the species Emiliania huxleyi, diatoms, and silicoflagellates) and , terrigenous matter from the Danube and nearby local rivers. The relative...this time period for the coccolithophorid Emiliania huxleyi to exist. The Black Sea was a fresh water environment before more than 5,000 years ago...and gradually became brackish; Emiliania huxleyi becameJ .. 4 established after the salinity exceeded 11 %o. The terrigenous matter supply remained
Change of Monascus pigment metabolism and secretion in different extractive fermentation process.
Chen, Gong; Tang, Rui; Tian, Xiaofei; Qin, Peng; Wu, Zhenqiang
2017-06-01
Monascus pigments that were generally produced intracellularly from Monascus spp. are important natural colorants in food industry. In this study, change of pigment metabolism and secretion was investigated through fed-batch extractive fermentation and continuous extractive fermentation. The biomass, secreting rate of pigment and total pigment yield closely correlated with the activated time of extractive fermentation as well as the composition of feeding nutrients. Metal ions played a key role in both the cell growth and pigment metabolism. Nitrogen source was necessary for a high productivity of biomass but not for high pigment yield. Furthermore, fermentation period for the fed-batch extractive fermentation could be reduced by 18.75% with a nitrogen source free feeding medium. Through a 30-day continuous extractive fermentation, the average daily productivity for total pigments reached 74.9 AU day -1 with an increase by 32.6 and 296.3% compared to that in a 6-day conventional batch fermentation and a 16-day fed-batch extractive fermentation, respectively. At the meantime, proportions of extracellular pigments increased gradually from 2.7 to 71.3%, and yellow pigments gradually became dominated in both intracellular and extracellular pigments in the end of continuous extractive fermentation. This findings showed that either fed-batch or continuous extractive fermentation acted as a promising method in the efficient production of Monascus pigments.
NASA Astrophysics Data System (ADS)
Ebisawa, Ken; Naoki, Iso
2012-07-01
X-ray intensities and spectra of the Seyfert galaxies are known to be variable. Some of the sources have characteristic seemingly broad iron line structure, and their spectral variations are small in the iron line energy band. MCG-6-30-15 is such an archetypal source, and Miyakawa (2011) proposed a "Variable Partial Covering (VPC)" model to explain its continuum spectral variation, seemingly broad iron line structure, and small spectral variation in the iron energy band simultaneously, only due to variation of a single parameter. That single parameter is the "partial covering fraction" to describe the geometrical fraction of the X-ray emitting area covered by the ionized absorbers in the line of sight. The intrinsic X-ray luminosity is hardly variable in this model. We have applied the VPC model to the 27 Seyfert galaxies observed with Suzaku, and found that spectral variations of the 22 sources are successfully explained by this model only varying the partial covering fraction. Intrinsic X-ray luminosities of Seyfert galaxies are not variable, as opposed to what they apparently seem, and gravitationally red-shifted iron line is not necessary. Those ionized absorbing clouds are most likely to be Broad Line Region (BLR) clouds, and we will be able to constrain the BLR structure from X-ray observations.
Shifting material source of Chinese Loess since ~2.7 Ma reflected by Sr isotopic composition.
Zhang, Wenfang; Chen, Jun; Li, Gaojun
2015-05-21
Deciphering the sources of eolian dust on the Chinese Loess Plateau (CLP) is fundamental to reconstruct paleo-wind patterns and paleo-environmental changes. Existing datasets show contradictory source evolutions of eolian dust on the CLP, both on orbital and tectonic timescales. Here, the silicate Sr and Nd isotopic compositions of a restricted grain size fraction (28-45 μm) were measured to trace the source evolution of the CLP since ~2.7 Ma. Our results revealed an unchanged source on orbital timescales but a gradual source shift from the Qilian Mountains to the Gobi Altay Mountains during the past 2.7 Ma. Both tectonic uplift and climate change may have played important roles for this shift. The later uplift of the Gobi Altay Mountains relative to the Qilian Mountains since 5 ± 3 Ma might be responsible for the increasing contribution of Gobi materials to the source deserts in Alxa arid lands. Enhanced winter monsoon may also facilitate transportation of Gobi materials from the Alxa arid lands to the CLP. The shifting source of Asian dust was also reflected in north Pacific sediments. The finding of this shifting source calls for caution when interpreting the long-term climate changes based on the source-sensitive proxies of the eolian deposits.
Delay Tolerant Networking on NASA's Space Communication and Navigation Testbed
NASA Technical Reports Server (NTRS)
Johnson, Sandra; Eddy, Wesley
2016-01-01
This presentation covers the status of the implementation of an open source software that implements the specifications developed by the CCSDS Working Group. Interplanetary Overlay Network (ION) is open source software and it implements specifications that have been developed by two international working groups through IETF and CCSDS. ION was implemented on the SCaN Testbed, a testbed located on an external pallet on ISS, by the GRC team. The presentation will cover the architecture of the system, high level implementation details, and issues porting ION to VxWorks.
All Source Analysis System (ASAS): Migration from VAX to Alpha AXP computer systems
NASA Technical Reports Server (NTRS)
Sjoholm-Sierchio, Michael J.; Friedman, Steven Z. (Editor)
1994-01-01
The Jet Propulsion Laboratory's (JPL's) experience migrating existing VAX applications to Digital Equipment Corporation's new Alpha AXP processor is covered. The rapid development approach used during the 10-month period required to migrate the All Source Analysis System (ASAS), 1.5 million lines of FORTRAN, C, and Ada code, is also covered. ASAS, an automated tactical intelligence system, was developed by the Jet Propulsion Laboratory for the U. S. Army. Other benefits achieved as a result of the significant performance improvements provided by Alpha AXP platform are also described.
Who pays for agricultural injury care?
Costich, Julia
2010-01-01
Analysis of 295 agricultural injury hospitalizations in a single state's hospital discharge database found that workers' compensation covered only 5% of the inpatient stays. Other sources were commercial health insurance (47%), Medicare (31%), and Medicaid (7%); 9% were uninsured. Estimated mean hospital and physician payments (not costs or charges) were $12,056 per hospitalization. Nearly one sixth (16%) of hospitalizations were either unreimbursed or covered by Medicaid, indicating a substantial cost-shift to public funding sources. Problems in characterizing agricultural injuries and states' exceptions to workers' compensation coverage mandates point to the need for comprehensive health coverage.
Tonozuka, Ryosuke; Yunoki, Shunji; Itoi, Takao; Sofuni, Atsushi; Tsuchiya, Takayoshi; Ishii, Kentaro; Tanaka, Reina; Honjo, Mitsuyoshi; Mukai, Shuntaro; Fujita, Mitsuru; Yamamoto, Kenjiro; Asai, Yasutsugu; Matsunami, Yukitoshi; Kurosawa, Takashi; Kojima, Hiroyuki; Nagakawa, Yuichi; Nagakawa, Yoshiyasu
2018-06-05
EUS-guided transmural drainage (EUS-TD) using a covered biflanged metal stent (CBFMS) and a conventional tubular biliary covered self-expandable metal stent (CSEMS) has recently been performed by EUS experts. However, appropriate traction force of the sheath to prevent the migration during stent deployment is well unknown. Herein, we assessed the anchoring force (AF) of the distal flange in CBFMSs and CSEMSs. The AFs of 4 CBFMSs (Stents AX, NG, PL, and SX) and 6 CSEMSs (Stents BF, BP, EG, HN, SP, and WF) were compared in an ex vivo setting. We assessed the AF produced by each stent using an EUS-TD model and an EUS-guided hepaticogastrostomy (EUS-HGS) model consisting of sheet-shaped specimens of the stomach, gelatin gel, and gelatin tubes. For CBFMSs, the maximum AF of Stent AX was significantly higher than those of Stents PL and SX (P < 0.05) in the porcine model. In the gelatin series, all stents except Stent NG showed a nearly similar AF. For CSEMSs, Stents HN, EG, BF, and WF showed gradual AF elevation in the porcine stomach. Stents SP and BP showed a lower AF than the other 4 stents. For the gelatin setting, the maximum AF of Stents HN, EG, and WF were higher than those of the other stents regardless of the type of specimens. The significance of the AF and traction distance according to the property of various CBFMSs and CSEMSs could be elucidated using ex-vivo models. This article is protected by copyright. All rights reserved.
Efficient Location of Research Reference Sources in the Field of Dance.
ERIC Educational Resources Information Center
Kissinger, Pat; Jay, Danielle
More than 45 basic dance reference research sources that would be useful to students, scholars, teachers, historians, and therapists are discussed in this bibliographic essay. Aspects of dance covered include choreography, criticism, teaching principles, aesthetic theory, dance therapy, and history. Sources are grouped by type: dictionaries and…
40 CFR 72.90 - Annual compliance certification report.
Code of Federal Regulations, 2014 CFR
2014-07-01
... is subject to the Acid Rain emissions limitations, the designated representative of the source at... the source and the affected units at the source in compliance with the Acid Rain Program, whether each... covered by the report in compliance with the requirements of the Acid Rain Program applicable to the unit...
40 CFR 72.90 - Annual compliance certification report.
Code of Federal Regulations, 2011 CFR
2011-07-01
... is subject to the Acid Rain emissions limitations, the designated representative of the source at... the source and the affected units at the source in compliance with the Acid Rain Program, whether each... covered by the report in compliance with the requirements of the Acid Rain Program applicable to the unit...
40 CFR 72.90 - Annual compliance certification report.
Code of Federal Regulations, 2012 CFR
2012-07-01
... is subject to the Acid Rain emissions limitations, the designated representative of the source at... the source and the affected units at the source in compliance with the Acid Rain Program, whether each... covered by the report in compliance with the requirements of the Acid Rain Program applicable to the unit...
40 CFR 72.90 - Annual compliance certification report.
Code of Federal Regulations, 2013 CFR
2013-07-01
... is subject to the Acid Rain emissions limitations, the designated representative of the source at... the source and the affected units at the source in compliance with the Acid Rain Program, whether each... covered by the report in compliance with the requirements of the Acid Rain Program applicable to the unit...
40 CFR 63.7182 - What parts of my facility does this subpart cover?
Code of Federal Regulations, 2010 CFR
2010-07-01
... (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE... subpart applies to each new, reconstructed, or existing affected source that you own or operate that manufactures semiconductors. (b) An affected source subject to this subpart is the collection of all...
Micrographics: A Bibliography of Sources.
ERIC Educational Resources Information Center
Thornberry, Patricia Lee; Michael, James D.
This extensive micrographics bibliography, which includes citations drawn from a literature search and prepared bibliographies, covers microforms, microfiche, and microfilm. Sections include 3 pages of book citations, 6 pages citing ERIC documents, and 33 pages of journal citations. Topics covered include microform library usage and usage in other…
Coronal Magnetic Field Topology and Source of Fast Solar Wind
NASA Technical Reports Server (NTRS)
Guhathakurta, M.; Sittler, E.; Fisher, R.; McComas, D.; Thompson, B.
1999-01-01
We have developed a steady state, 2D semi-empirical MHD model of the solar corona and the solar wind with many surprising results. This model for the first time shows, that the boundary between the fast and the slow solar wind as observed by Ulysses beyond 1 AU, is established in the low corona. The fastest wind observed by Ulysses (680-780 km/s) originates from the polar coronal holes at 70 -90 deg. latitude at the Sun. Rapidly diverging magnetic field geometry accounts for the fast wind reaching down to a latitude of +/- 30 deg. at the orbit of Earth. The gradual increase in the fast wind observed by Ulysses, with latitude, can be explained by an increasing field strength towards the poles, which causes Alfven wave energy flux to increase towards the poles. Empirically, there is a direct relationship between this gradual increase in wind speed and the expansion factor, f, computed at r greater than 20%. This relationship is inverse if f is computed very close to the Sun.
The acquisition of biological knowledge during childhood: Cognitive conflict or tabula rasa?
NASA Astrophysics Data System (ADS)
Lawson, Anton E.
Clinical interviews were conducted with three elementary school children, who varied in age but not in family or school environment, to determine the extent to which they held naive misconceptions about important biological topics and to determine agewise trends in the development of biological knowledge. Does early biological knowledge acquisition follow a pattern of spontaneous naive theory construction and cognitive conflict or does it follow a pattern of gradual accretion to an initially blank slate? Contrary to findings in the physical sciences, little evidence was found for biological misconceptions as knowledge acquisition appeared to more directly follow the gradual accretion hypothesis with the primary source of that knowledge adult authority rather than personal experience. However, conceptual change teaching is still advocated due to its ability to provoke students to consider and test alternative conceptions (even if they are not their own) as a means of encouraging the development of important general reasoning patterns utilized in the testing of causal hypotheses.
Non-linear intensification of Sahel rainfall as a possible dynamic response to future warming
NASA Astrophysics Data System (ADS)
Schewe, Jacob; Levermann, Anders
2017-07-01
Projections of the response of Sahel rainfall to future global warming diverge significantly. Meanwhile, paleoclimatic records suggest that Sahel rainfall is capable of abrupt transitions in response to gradual forcing. Here we present climate modeling evidence for the possibility of an abrupt intensification of Sahel rainfall under future climate change. Analyzing 30 coupled global climate model simulations, we identify seven models where central Sahel rainfall increases by 40 to 300 % over the 21st century, owing to a northward expansion of the West African monsoon domain. Rainfall in these models is non-linearly related to sea surface temperature (SST) in the tropical Atlantic and Mediterranean moisture source regions, intensifying abruptly beyond a certain SST warming level. We argue that this behavior is consistent with a self-amplifying dynamic-thermodynamical feedback, implying that the gradual increase in oceanic moisture availability under warming could trigger a sudden intensification of monsoon rainfall far inland of today's core monsoon region.
Global Monitoring of Martian Surface Albedo Changes from Orbital Observations
NASA Astrophysics Data System (ADS)
Geissler, P.; Enga, M.; Mukherjee, P.
2013-12-01
Martian surface changes were first observed from orbit during the Mariner 9 and Viking Orbiter missions. They were found to be caused by eolian processes, produced by deposition of dust during regional and global dust storms and subsequent darkening of the surface through erosion and transportation of dust and sand. The albedo changes accumulated in the 20 years between Viking and Mars Global Surveyor were sufficient to alter the global circulation of winds and the climate of Mars according to model calculations (Fenton et al., Nature 2007), but little was known about the timing or frequency of the changes. Since 1999, we have had the benefit of continuous monitoring by a series of orbiting spacecraft that continues today with Mars Reconnaissance Orbiter, Mars Odyssey, and Mars Express. Daily synoptic observations enable us to determine whether the surface albedo changes are gradual or episodic in nature and to record the seasons that the changes take place. High resolution images of surface morphology and atmospheric phenomena help identify the physical mechanisms responsible for the changes. From these data, we hope to learn the combinations of atmospheric conditions and sediment properties that produce surface changes on Mars and possibly predict when they will take place in the future. Martian surface changes are particularly conspicuous in low albedo terrain, where even a thin layer of bright dust brightens the surface drastically. Equatorial dark areas are repeatedly coated and recoated by dust, which is later shed from the surface by a variety of mechanisms. An example is Syrtis Major, suddenly buried in bright dust by the global dust storm of 2001. Persistent easterly winds blew much of the dust cover away over the course of the next Martian year, but episodic changes continue today, particularly during southern summer when regional dust storms are rife. Another such region is Solis Planum, south of the Valles Marineris, where changes take place relentlessly in all seasons as bright dust and dark sand battle to dominate the landscape. Elsewhere, gradual processes steadily shift albedo boundaries between bright and dark terrain. Dark terrain near the Spirit rover landing site is gradually spreading to the north, driven by seasonal southerly winds. A bright fringe of newly deposited dust appears ahead of the moving boundary, populated by wind streaks and dust avalanches. Dark terrain at higher latitudes gradually creeps towards the equator by the dust cleaning action of dust devils, for example at Nilosytis (43°N, 85°E). Much less obvious is the deposition and erosion of dust on already bright, dust-covered terrain. Changes in the distribution of fresh dust take place frequently in the region surrounding the Tharsis Montes. Dust in this high altitude zone is constantly on the move as faint dark streaks mark the removal of recently deposited dust that is only slightly brighter than the dust already settled on the surface. Dramatic deposition of dust onto dusty terrain took place at much lower elevations in northwestern Amazonis between 2002 and 2005. Since then, the dust has been energetically eroded by towering dust devils that cluster here each summer.
Pulsed Neutron Powder Diffraction for Materials Science
NASA Astrophysics Data System (ADS)
Kamiyama, T.
2008-03-01
The accelerator-based neutron diffraction began in the end of 60's at Tohoku University which was succeeded by the four spallation neutron facilities with proton accelerators at the High Energy Accelerator Research Organization (Japan), Argonne National Laboratory and Los Alamos Laboratory (USA), and Rutherford Appleton Laboratory (UK). Since then, the next generation source has been pursued for 20 years, and 1MW-class spallation neutron sources will be appeared in about three years at the three parts of the world: Japan, UK and USA. The joint proton accelerator project (J-PARC), a collaborative project between KEK and JAEA, is one of them. The aim of the talk is to describe about J-PARC and the neutron diffractometers being installed at the materials and life science facility of J-PARC. The materials and life science facility of J-PARC has 23 neutron beam ports and will start delivering the first neutron beam of 25 Hz from 2008 May. Until now, more than 20 proposals have been reviewed by the review committee, and accepted proposal groups have started to get fund. Those proposals include five polycrystalline diffractometers: a super high resolution powder diffractometer (SHRPD), a 0.2%-resolution powder diffractometer of Ibaraki prefecture (IPD), an engineering diffractometers (Takumi), a high intensity S(Q) diffractometer (VSD), and a high-pressure dedicated diffractometer. SHRPD, Takumi and IPD are being designed and constructed by the joint team of KEK, JAEA and Ibaraki University, whose member are originally from the KEK powder group. These three instruments are expected to start in 2008. VSD is a super high intensity diffractometer with the highest resolution of Δd/d = 0.3%. VSD can measure rapid time-dependent phenomena of crystalline materials as well as glass, liquid and amorphous materials. The pair distribution function will be routinely obtained by the Fourier transiformation of S(Q) data. Q range of VSD will be as wide as 0.01 Å-1
Human influences on trophic cascades along rocky shores
Lindberg, D.R.; Estes, J.A.; Warheit, K.I.
1998-01-01
A three-trophic-level interaction among American Black Oystercatchers (Haematopus bachmani), limpets (Lottia spp.), and erect fleshy algae in rocky intertidal communities of central and southern California was documented via manipulative and 'natural' experiments. Removal of the territorial limpet (Lottia gigantea) initially caused large increases in the percent cover of erect fleshy algae, followed by a more gradual increase in density of small limpets (Lottia spp.) and a decline in algal cover. Algal cover increased following the removal of small limpets at the sites from which L. gigantea had been removed earlier, thus demonstrating that the large and small limpets had similar inhibitory effects on plant populations. A comparison of sites with and without oyster-catchers showed that L. gigantea occupied substrate inclinations in proportion to their availability at sites where oystercatchers were rare, whereas the distribution of L. gigantea was skewed toward vertically inclined substrates where oystercatchers were common. Survival rates of limpets translocated to horizontal and vertical substrates were similar in sites lacking oystercatcher predation, but were much lower on horizontal substrates where oystercatchers were common. Our results are consistent with those from several prior studies in demonstrating that shorelines frequented by humans typically lack oystercatchers. Humans also exploit L. gigantea and reduce populations to low densities of small individuals. These findings may explain why the midlittoral zone of rocky intertidal communities in western North America are so often dominated by high population densities of small limpets.
Zeng, Hong-Da; Du, Zi-Xian; Yang, Yu-Sheng; Li, Xi-Bo; Zhang, Ya-Chun; Yang, Zhi-Feng
2010-03-01
By using Vario EL III element analyzer, the vertical distribution characteristics of soil organic carbon (SOC) and light-fraction organic carbon (LFOC) in the lawn, patch plantation, and reed wetland at river banks of Fuzhou urban area were studied in July 2007. For all the three land cover types, the SOC and LFOC contents were the highest in surface soil layer, and declined gradually with soil depth. Compared with reed wetland, the lawn and patch plantation had higher SOC and LFOC contents in each layer of the soil profile (0-60 cm), and the lawn had significantly higher contents of SOC and LFOC in 0-20 cm soil layer, compared with the patch plantation. After the reed wetland was converted into lawn and patch plantation, the SOC stock in the soil profile was increased by 94.8% and 72.0%, and the LFOC stock was increased by 225% and 93%, respectively. Due to the changes of plant species, plant density, and management measure, the conversion from natural wetland into human-manipulated green spaces increased the SOC and LFOC stocks in the soil profile, and improved the soil quality. Compared with the SOC, soil LFOC was more sensitive to land use/cover change, especially for those in 0-20 cm soil layer.
Verification Games: Crowd-Sourced Formal Verification
2016-03-01
VERIFICATION GAMES : CROWD-SOURCED FORMAL VERIFICATION UNIVERSITY OF WASHINGTON MARCH 2016 FINAL TECHNICAL REPORT...DATES COVERED (From - To) JUN 2012 – SEP 2015 4. TITLE AND SUBTITLE VERIFICATION GAMES : CROWD-SOURCED FORMAL VERIFICATION 5a. CONTRACT NUMBER FA8750...clarification memorandum dated 16 Jan 09. 13. SUPPLEMENTARY NOTES 14. ABSTRACT Over the more than three years of the project Verification Games : Crowd-sourced
The Earth: Plasma Sources, Losses, and Transport Processes
NASA Astrophysics Data System (ADS)
Welling, Daniel T.; André, Mats; Dandouras, Iannis; Delcourt, Dominique; Fazakerley, Andrew; Fontaine, Dominique; Foster, John; Ilie, Raluca; Kistler, Lynn; Lee, Justin H.; Liemohn, Michael W.; Slavin, James A.; Wang, Chih-Ping; Wiltberger, Michael; Yau, Andrew
2015-10-01
This paper reviews the state of knowledge concerning the source of magnetospheric plasma at Earth. Source of plasma, its acceleration and transport throughout the system, its consequences on system dynamics, and its loss are all discussed. Both observational and modeling advances since the last time this subject was covered in detail (Hultqvist et al., Magnetospheric Plasma Sources and Losses, 1999) are addressed.
Code of Federal Regulations, 2010 CFR
2010-07-01
... composites production facility is a new affected source or an existing affected source? 63.5795 Section 63... for Hazardous Air Pollutants: Reinforced Plastic Composites Production What This Subpart Covers § 63.5795 How do I know if my reinforced plastic composites production facility is a new affected source or...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-08-23
...This action announces how the EPA proposes to address the reviews of the new source performance standards for volatile organic compound and sulfur dioxide emissions from natural gas processing plants. We are proposing to add to the source category list any oil and gas operation not covered by the current listing. This action also includes proposed amendments to the existing new source performance standards for volatile organic compounds from natural gas processing plants and proposed standards for operations that are not covered by the existing new source performance standards. In addition, this action proposes how the EPA will address the residual risk and technology review conducted for the oil and natural gas production and natural gas transmission and storage national emission standards for hazardous air pollutants. This action further proposes standards for emission sources within these two source categories that are not currently addressed, as well as amendments to improve aspects of these national emission standards for hazardous air pollutants related to applicability and implementation. Finally, this action addresses provisions in these new source performance standards and national emission standards for hazardous air pollutants related to emissions during periods of startup, shutdown and malfunction.
Development of a land-cover characteristics database for the conterminous U.S.
Loveland, Thomas R.; Merchant, J.W.; Ohlen, D.O.; Brown, Jesslyn F.
1991-01-01
Information regarding the characteristics and spatial distribution of the Earth's land cover is critical to global environmental research. A prototype land-cover database for the conterminous United States designed for use in a variety of global modelling, monitoring, mapping, and analytical endeavors has been created. The resultant database contains multiple layers, including the source AVHRR data, the ancillary data layers, the land-cover regions defined by the research, and translation tables linking the regions to other land classification schema (for example, UNESCO, USGS Anderson System). The land-cover characteristics database can be analyzed, transformed, or aggregated by users to meet a broad spectrum of requirements. -from Authors
40 CFR 63.9882 - What parts of my plant does this subpart cover?
Code of Federal Regulations, 2010 CFR
2010-07-01
... CATEGORIES (CONTINUED) National Emissions Standards for Hazardous Air Pollutants for Primary Magnesium... affected sources are each new and existing primary magnesium refining facility. (b) This subpart covers emissions from each spray dryer stack, magnesium chloride storage bins scrubber stack, melt/reactor system...
40 CFR 63.9882 - What parts of my plant does this subpart cover?
Code of Federal Regulations, 2012 CFR
2012-07-01
... CATEGORIES (CONTINUED) National Emissions Standards for Hazardous Air Pollutants for Primary Magnesium... affected sources are each new and existing primary magnesium refining facility. (b) This subpart covers emissions from each spray dryer stack, magnesium chloride storage bins scrubber stack, melt/reactor system...
40 CFR 63.9882 - What parts of my plant does this subpart cover?
Code of Federal Regulations, 2014 CFR
2014-07-01
... CATEGORIES (CONTINUED) National Emissions Standards for Hazardous Air Pollutants for Primary Magnesium... affected sources are each new and existing primary magnesium refining facility. (b) This subpart covers emissions from each spray dryer stack, magnesium chloride storage bins scrubber stack, melt/reactor system...
40 CFR 63.9882 - What parts of my plant does this subpart cover?
Code of Federal Regulations, 2011 CFR
2011-07-01
... CATEGORIES (CONTINUED) National Emissions Standards for Hazardous Air Pollutants for Primary Magnesium... affected sources are each new and existing primary magnesium refining facility. (b) This subpart covers emissions from each spray dryer stack, magnesium chloride storage bins scrubber stack, melt/reactor system...
40 CFR 63.9882 - What parts of my plant does this subpart cover?
Code of Federal Regulations, 2013 CFR
2013-07-01
... CATEGORIES (CONTINUED) National Emissions Standards for Hazardous Air Pollutants for Primary Magnesium... affected sources are each new and existing primary magnesium refining facility. (b) This subpart covers emissions from each spray dryer stack, magnesium chloride storage bins scrubber stack, melt/reactor system...
LAND-COVER CHARACTERIZATION AND CHANGE DETECTION USING MULTI-TEMPORAL MODIS NDIV DATA
Land-cover (LC) composition and conversions are important factors that affect ecosystem condition and function. These data are frequently used as a primary data source to generate landscape-based metrics to assess landscape condition at multiple assessment scales. The use of sate...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gastelum, Zoe N.; Whitney, Paul D.; White, Amanda M.
2013-07-15
Pacific Northwest National Laboratory has spent several years researching, developing, and validating large Bayesian network models to support integration of open source data sets for nuclear proliferation research. Our current work focuses on generating a set of interrelated models for multi-source assessment of nuclear programs, as opposed to a single comprehensive model. By using this approach, we can break down the models to cover logical sub-problems that can utilize different expertise and data sources. This approach allows researchers to utilize the models individually or in combination to detect and characterize a nuclear program and identify data gaps. The models operatemore » at various levels of granularity, covering a combination of state-level assessments with more detailed models of site or facility characteristics. This paper will describe the current open source-driven, nuclear nonproliferation models under development, the pros and cons of the analytical approach, and areas for additional research.« less
A new global 1-km dataset of percentage tree cover derived from remote sensing
DeFries, R.S.; Hansen, M.C.; Townshend, J.R.G.; Janetos, A.C.; Loveland, Thomas R.
2000-01-01
Accurate assessment of the spatial extent of forest cover is a crucial requirement for quantifying the sources and sinks of carbon from the terrestrial biosphere. In the more immediate context of the United Nations Framework Convention on Climate Change, implementation of the Kyoto Protocol calls for estimates of carbon stocks for a baseline year as well as for subsequent years. Data sources from country level statistics and other ground-based information are based on varying definitions of 'forest' and are consequently problematic for obtaining spatially and temporally consistent carbon stock estimates. By combining two datasets previously derived from the Advanced Very High Resolution Radiometer (AVHRR) at 1 km spatial resolution, we have generated a prototype global map depicting percentage tree cover and associated proportions of trees with different leaf longevity (evergreen and deciduous) and leaf type (broadleaf and needleleaf). The product is intended for use in terrestrial carbon cycle models, in conjunction with other spatial datasets such as climate and soil type, to obtain more consistent and reliable estimates of carbon stocks. The percentage tree cover dataset is available through the Global Land Cover Facility at the University of Maryland at http://glcf.umiacs.umd.edu.
Upstream watershed condition predicts rural children's health across 35 developing countries.
Herrera, Diego; Ellis, Alicia; Fisher, Brendan; Golden, Christopher D; Johnson, Kiersten; Mulligan, Mark; Pfaff, Alexander; Treuer, Timothy; Ricketts, Taylor H
2017-10-09
Diarrheal disease (DD) due to contaminated water is a major cause of child mortality globally. Forests and wetlands can provide ecosystem services that help maintain water quality. To understand the connections between land cover and childhood DD, we compiled a database of 293,362 children in 35 countries with information on health, socioeconomic factors, climate, and watershed condition. Using hierarchical models, here we find that higher upstream tree cover is associated with lower probability of DD downstream. This effect is significant for rural households but not for urban households, suggesting differing dependence on watershed conditions. In rural areas, the effect of a 30% increase in upstream tree cover is similar to the effect of improved sanitation, but smaller than the effect of improved water source, wealth or education. We conclude that maintaining natural capital within watersheds can be an important public health investment, especially for populations with low levels of built capital.Globally diarrheal disease through contaminated water sources is a major cause of child mortality. Here, the authors compile a database of 293,362 children in 35 countries and find that upstream tree cover is linked to a lower probability of diarrheal disease and that increasing tree cover may lower mortality.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gandini, Roberto; Pipitone, Vincenzo; Konda, Daniel, E-mail: danielkonda@yahoo.com
2005-01-15
A 68-year-old woman presenting with gastrointestinal bleeding (hematocrit 19.3%) and in a critical clinical condition (American Society of Anesthesiologists grade 4) from a giant superior mesenteric artery pseudoaneurysm (196.0 x 131.4 mm) underwent emergency endovascular treatment. The arterial tear supplying the pseudoaneurysm was excluded using a 5.0 mm diameter and 31 mm long monorail expanded polytetrafluoroethylene (ePTFE)-covered self-expanding nitinol stent. Within 6 days of the procedure, a gradual increase in hemoglobin levels and a prompt improvement in the clinical condition were observed. Multislice CT angiograms performed immediately, 5 days, 30 days and 3 months after the procedure confirmed the completemore » exclusion of the pseudoaneurysm.« less
Operation quality assessment model for video conference system
NASA Astrophysics Data System (ADS)
Du, Bangshi; Qi, Feng; Shao, Sujie; Wang, Ying; Li, Weijian
2018-01-01
Video conference system has become an important support platform for smart grid operation and management, its operation quality is gradually concerning grid enterprise. First, the evaluation indicator system covering network, business and operation maintenance aspects was established on basis of video conference system's operation statistics. Then, the operation quality assessment model combining genetic algorithm with regularized BP neural network was proposed, which outputs operation quality level of the system within a time period and provides company manager with some optimization advice. The simulation results show that the proposed evaluation model offers the advantages of fast convergence and high prediction accuracy in contrast with regularized BP neural network, and its generalization ability is superior to LM-BP neural network and Bayesian BP neural network.
The Astrophysics Source Code Library by the numbers
NASA Astrophysics Data System (ADS)
Allen, Alice; Teuben, Peter; Berriman, G. Bruce; DuPrie, Kimberly; Mink, Jessica; Nemiroff, Robert; Ryan, PW; Schmidt, Judy; Shamir, Lior; Shortridge, Keith; Wallin, John; Warmels, Rein
2018-01-01
The Astrophysics Source Code Library (ASCL, ascl.net) was founded in 1999 by Robert Nemiroff and John Wallin. ASCL editors seek both new and old peer-reviewed papers that describe methods or experiments that involve the development or use of source code, and add entries for the found codes to the library. Software authors can submit their codes to the ASCL as well. This ensures a comprehensive listing covering a significant number of the astrophysics source codes used in peer-reviewed studies. The ASCL is indexed by both NASA’s Astrophysics Data System (ADS) and Web of Science, making software used in research more discoverable. This presentation covers the growth in the ASCL’s number of entries, the number of citations to its entries, and in which journals those citations appear. It also discusses what changes have been made to the ASCL recently, and what its plans are for the future.
Controlling hazardous energy sources (lockout/tagout)
NASA Technical Reports Server (NTRS)
Dominguez, Manuel B.
1991-01-01
The minimum requirements as established by the Occupational Safety and Health Administration (OSHA) standard 29 CFR 1910.147 are discussed for preventing the unexpected operation of equipment or release of energy which could cause injury to personnel, damage to equipment, harm to the environment, or loss or compromise of test data. Safety requirements both for government and contractor personnel are explained for potentially hazardous energy sources during work operations at LeRC (Cleveland and Plum Brook Stations). Basic rules are presented to ensure protection against harmful exposures, and baseline implementation requirements are discussed from which detailed lockout/tagout procedures can be developed for individual equipment items. Examples of energy sources covered by this document include electrical, pneumatic, mechanical, chemical, cryogenic, thermal, spring tension/compression suspended or moving loads, and other potentially hazardous sources. Activities covered by this standard include, but are not limited to, construction, maintenance, installation, calibration, inspection, cleaning, or repair.
Controlling hazardous energy sources (lockout/tagout)
NASA Astrophysics Data System (ADS)
Dominguez, Manuel B.
1991-10-01
The minimum requirements as established by the Occupational Safety and Health Administration (OSHA) standard 29 CFR 1910.147 are discussed for preventing the unexpected operation of equipment or release of energy which could cause injury to personnel, damage to equipment, harm to the environment, or loss or compromise of test data. Safety requirements both for government and contractor personnel are explained for potentially hazardous energy sources during work operations at LeRC (Cleveland and Plum Brook Stations). Basic rules are presented to ensure protection against harmful exposures, and baseline implementation requirements are discussed from which detailed lockout/tagout procedures can be developed for individual equipment items. Examples of energy sources covered by this document include electrical, pneumatic, mechanical, chemical, cryogenic, thermal, spring tension/compression suspended or moving loads, and other potentially hazardous sources. Activities covered by this standard include, but are not limited to, construction, maintenance, installation, calibration, inspection, cleaning, or repair.
NASA Astrophysics Data System (ADS)
Ohte, N.; Sebestyen, S. D.; Doctor, D. H.; Wankel, S. D.; Shanley, J. B.; Kendall, C.; Boyer, E. W.
2003-12-01
To quantify the contributions of atmospheric nitrogen deposition and mechanisms of nitrate discharge to stream, nitrogen chemistry and isotopes (δ 15N and δ 18O of NO3-) of streamwater were studied as part of an ongoing study of nutrient dynamics at the Sleepers River Research Watershed in Vermont, USA. We employed novel analytical procedures for high throughput of NO3- isotopic measurements. The denitrifier method for measurement of δ 15N and δ 18O of NO3- requires a smaller volume of water samples than previously applied methods, thus it enables fine resolution analysis of isotopes for stream, well, and soil water samples. Samples were collected throughout the spring 2003 snowmelt. Snowmelt runoff was initiated in the middle of March and peaked at the end of the month. Then, the runoff rate decreased gradually through April and May, and responded to several storm events. The highest concentration of NO3- in the stream was observed at the beginning of snowmelt (the end of March), and thereafter it declined continuously. The temporal course of NO3- discharge process during snowmelt period was divided into four phases based on changes in the relationship between runoff rate and NO3- concentration. During the earliest phase (very low runoff rate and highest NO3- concentration) isotope signatures, especially δ 18O of NO3-, indicated higher contribution of the atmospherically derived NO3-, meaning that the direct discharge from snow pack was the dominant source of NO3- to the stream. This also suggested that streamwater consisted only of a small volume of groundwater discharge and melt water of the in-stream snow pack and/or stream-covering snow pack. The δ 15N and δ 18O isotope compositions of NO3- during the middle phase of snowmelt indicated that the contribution of the NO3- generated by nitrifiers in soil increased gradually accompanied with increase of groundwater level. These detailed descriptions in the changes of NO3- discharge during snowmelt events were enabled by the dual-isotope analysis of NO3-. The fine resolution isotope analysis of NO3- in our experiment can provide advantages for elucidating the discharge mechanisms of nitrogen in forested watersheds with high atmospheric nitrogen depositions.
[Reducing nutrients loss by plastic film covering chemical fertilizers].
Chen, Huo-jun; Wei, Ze-bin; Wu, Qi-tang; Zeng, Shu-cai
2010-03-01
With the low utilization rate of fertilizers by crop and the growing amount of fertilizer usage,the agricultural non-point source pollution in China is becoming more and more serious. The field experiments planting corns were conducted, in which the applied chemical fertilizers were recovered with plastic film to realize the separation of fertilizers from rain water. In the experiments, the influences of different fertilizing treatments on the growing and production of sweet corn were observed. The fertilizer utilization rate and the nutrient contents in surface run-off water with and without the film covering were also determined. Results showed that, with only 70% of the normal amount of fertilizers,the sweet corn could already get high yield under the experimental soil conditions. Soil analysis after corn crops showed that the amounts of available N, P and K in the soil increased obviously with the film-covering, and the decreasing order was: 100% fertilizers with film-covering > 70% fertilizers with film-covering > 100% fertilizers, 70% fertilizers > no fertilizer. The average utilization coefficients of fertilizers by the crop were 42%-87%, 0%-3%, 5%-15% respectively for N, P and K. It was higher with film-covering than that without covering, especially for the high fertilization treatment. Analysis of water samples collected for eight run-off events showed that, without film-covering, N, P and K average concentrations in the runoff waters with fertilizations were 27.72, 2.70 and 7.07 mg x L(-1), respectively. And they were reduced respectively by 39.54%, 28.05%, 43.74% with the film-covering. This can give significant benefits to the decrease of agricultural non-point source pollution and water eutrophication.
Siudek, Patrycja
2016-12-01
In the present paper, the inter-seasonal Hg variability in snow cover was examined based on multivariate statistical analysis of chemical and meteorological data. Samples of freshly fallen snow cover were collected at the semi-urban site in Poznań (central Poland), during 3-month field measurements in winter 2013. It was showed that concentrations of atmospherically deposited Hg were highly variable in snow cover, from 0.43 to 12.5 ng L -1 , with a mean value of 4.62 ng L -1 . The highest Hg concentration in snow cover coincided with local intensification of fossil fuel burning, indicating large contribution from various anthropogenic sources such as commercial and domestic heating, power generation plants, and traffic-related pollution. Moreover, the variability of Hg in collected snow samples was associated with long-range transport of pollutants, nocturnal inversion layer, low boundary layer height, and relatively low air temperature. For three snow episodes, Hg concentration in snow cover was attributed to southerly advection, suggesting significant contribution from the highly polluted region of Poland (Upper Silesia) and major European industrial hotspots. However, the peak Hg concentration was measured in samples collected during predominant N to NE advection of polluted air masses and after a relatively longer period without precipitation. Such significant contribution to the higher Hg accumulation in snow cover was associated with intensive emission from anthropogenic sources (coal combustion) and atmospheric conditions in this area. These results suggest that further measurements are needed to determine how the Hg transformation paths in snow cover change in response to longer/shorter duration of snow cover occurrence and to determine the interactions between mercury and absorbing carbonaceous aerosols in the light of climate change.
LC-MS/MS Identification of Species-Specific Muscle Peptides in Processed Animal Proteins.
Marchis, Daniela; Altomare, Alessandra; Gili, Marilena; Ostorero, Federica; Khadjavi, Amina; Corona, Cristiano; Ru, Giuseppe; Cappelletti, Benedetta; Gianelli, Silvia; Amadeo, Francesca; Rumio, Cristiano; Carini, Marina; Aldini, Giancarlo; Casalone, Cristina
2017-12-06
An innovative analytical strategy has been applied to identify signature peptides able to distinguish among processed animal proteins (PAPs) derived from bovine, pig, fish, and milk products. Proteomics was first used to elucidate the proteome of each source. Starting from the identified proteins and using a funnel based approach, a set of abundant and well characterized peptides with suitable physical-chemical properties (signature peptides) and specific for each source was selected. An on-target LC-ESI-MS/MS method (MRM mode) was set up using standard peptides and was then applied to selectively identify the PAP source and also to distinguish proteins from bovine carcass and milk proteins. We believe that the method described meets the request of the European Commission which has developed a strategy for gradually lifting the "total ban" toward "species to species ban", therefore requiring official methods for species-specific discrimination in feed.
Russian History; A Guide to Reference Sources.
ERIC Educational Resources Information Center
McGill Univ., Montreal (Quebec). McLennan Library.
This guide identifies reference sources for the study of Russian and Soviet history available in the McGill University (Montreal) McLennan Library. Russian, English, French, and German language works covering Russian history from its origins to World War II are included. The guide is arranged in two parts: general reference sources and…
It is expected that human activity and terrestrial input (i.e., leaf litter, throughfall) will be the dominant sources of N and P, but that sources will vary greatly at small spatial scales. Preliminary work suggests that tree species cover, soil characteristics and snowmel...
40 CFR 63.5490 - What parts of my plant does this subpart cover?
Code of Federal Regulations, 2011 CFR
2011-07-01
... to each new, reconstructed, or existing affected source for the Miscellaneous Viscose Processes and Cellulose Ethers Production source categories. (b) The affected source for the Miscellaneous Viscose... paragraph (c)(3) or (4) of this section. (1) The input to the storage vessel from your viscose process or...
40 CFR 63.5490 - What parts of my plant does this subpart cover?
Code of Federal Regulations, 2010 CFR
2010-07-01
... to each new, reconstructed, or existing affected source for the Miscellaneous Viscose Processes and Cellulose Ethers Production source categories. (b) The affected source for the Miscellaneous Viscose... paragraph (c)(3) or (4) of this section. (1) The input to the storage vessel from your viscose process or...
7 CFR 1.413 - Submission of a sourcing area application.
Code of Federal Regulations, 2010 CFR
2010-01-01
... sourced is located. Where the sourcing area application will cover purchases from more than one agency, application is to be made to the agency from which the applicant expects to purchase the preponderance of its... agency concerned. The lead agency shall make the decision in consultation with, and upon co-signature of...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-06-03
... National Emission Standards for Hazardous Air Pollutants: Area Source Standards for Paints and Allied... when they should not be covered. This action clarifies text of the National Emission Standards for Hazardous Air Pollutants: Paints and Allied Products Manufacturing Area Source Standards which was published...
Attosecond light sources in the water window
NASA Astrophysics Data System (ADS)
Ren, Xiaoming; Li, Jie; Yin, Yanchun; Zhao, Kun; Chew, Andrew; Wang, Yang; Hu, Shuyuan; Cheng, Yan; Cunningham, Eric; Wu, Yi; Chini, Michael; Chang, Zenghu
2018-02-01
As a compact and burgeoning alternative to synchrotron radiation and free-electron lasers, high harmonic generation (HHG) has proven its superiority in static and time-resolved extreme ultraviolet spectroscopy for the past two decades and has recently gained many interests and successes in generating soft x-ray emissions covering the biologically important water window spectral region. Unlike synchrotron and free-electron sources, which suffer from relatively long pulse width or large time jitter, soft x-ray sources from HHG could offer attosecond time resolution and be synchronized with their driving field to investigate time-resolved near edge absorption spectroscopy, which could reveal rich structural and dynamical information of the interrogated samples. In this paper, we review recent progresses on generating and characterizing attosecond light sources in the water window region. We show our development of an energetic, two-cycle, carrier-envelope phase stable laser source at 1.7 μm and our achievement in producing a 53 as soft x-ray pulse covering the carbon K-edge in the water window. Such source paves the ways for the next generation x-ray spectroscopy with unprecedented temporal resolution.
Automated detection of ice cliffs within supraglacial debris cover
NASA Astrophysics Data System (ADS)
Herreid, Sam; Pellicciotti, Francesca
2018-05-01
Ice cliffs within a supraglacial debris cover have been identified as a source for high ablation relative to the surrounding debris-covered area. Due to their small relative size and steep orientation, ice cliffs are difficult to detect using nadir-looking space borne sensors. The method presented here uses surface slopes calculated from digital elevation model (DEM) data to map ice cliff geometry and produce an ice cliff probability map. Surface slope thresholds, which can be sensitive to geographic location and/or data quality, are selected automatically. The method also attempts to include area at the (often narrowing) ends of ice cliffs which could otherwise be neglected due to signal saturation in surface slope data. The method was calibrated in the eastern Alaska Range, Alaska, USA, against a control ice cliff dataset derived from high-resolution visible and thermal data. Using the same input parameter set that performed best in Alaska, the method was tested against ice cliffs manually mapped in the Khumbu Himal, Nepal. Our results suggest the method can accommodate different glaciological settings and different DEM data sources without a data intensive (high-resolution, multi-data source) recalibration.
Environmental news: coverage of the Earth Summit by Brazilian newspapers.
Reis, R
1999-12-01
This article examines how two important Brazilian newspapers (Floha de S. Paulo and O Globo) covered the UN Conference on Environment and Development (UNCED) or Earth Summit. The analysis will also determine the characteristics of the environmental media and its significance when it comes to coverage of environmental issues. This article provides historical background information on the environmental media in the US and in Brazil, contextual information on the Earth Summit, a content analysis of stories about UNCED published by the two Brazilian newspapers. Overall, 649 news items were used to determine the type of sources used, as well as the kind of issues covered. The analysis showed that government officials were the most frequently cited sources, while environmentalists and scientists were all but ignored as news sources. The analysis also indicated that economic issues were surprisingly prominent in the coverage. These results are compatible with the previous studies done in several countries and indicate that environmental media are still extremely reliant on "official" voices. The finding also highlight the fact that the range of issues covered by the environmental media largely reflects the perceived public agenda.
46 CFR 38.05-20 - Insulation-TB/ALL.
Code of Federal Regulations, 2013 CFR
2013-10-01
... possible high temperature or source of ignition shall be either: (i) Incombustible, complying with the... Cellular Polymeric Materials,” (incorporated by reference, see § 38.01-3) and covered by a suitable steel cover. (2) Insulation in a location protected against possible ignition by enclosure in a tight steel...
46 CFR 38.05-20 - Insulation-TB/ALL.
Code of Federal Regulations, 2014 CFR
2014-10-01
... possible high temperature or source of ignition shall be either: (i) Incombustible, complying with the... Cellular Polymeric Materials,” (incorporated by reference, see § 38.01-3) and covered by a suitable steel cover. (2) Insulation in a location protected against possible ignition by enclosure in a tight steel...
46 CFR 38.05-20 - Insulation-TB/ALL.
Code of Federal Regulations, 2012 CFR
2012-10-01
... possible high temperature or source of ignition shall be either: (i) Incombustible, complying with the... Cellular Polymeric Materials,” (incorporated by reference, see § 38.01-3) and covered by a suitable steel cover. (2) Insulation in a location protected against possible ignition by enclosure in a tight steel...
Hydrologic, land cover and seasonal patterns of waterborne pathogens in great lakes tributaries
USDA-ARS?s Scientific Manuscript database
Great Lakes tributaries deliver waterborne pathogens from a host of sources. To examine the hydrologic, land cover, and seasonal variability of waterborne pathogens, protozoa (2), pathogenic bacteria (4) and human (8) and bovine (8) viruses from eight rivers were monitored in the Great Lakes watersh...
40 CFR 63.8184 - What parts of my plant does this subpart cover?
Code of Federal Regulations, 2014 CFR
2014-07-01
... in the manufacture of product chlorine, product caustic, and by-product hydrogen at a plant site. This subpart covers mercury emissions from by-product hydrogen streams, end box ventilation system vents, and fugitive emission sources associated with cell rooms, hydrogen systems, caustic systems, and...
40 CFR 63.8184 - What parts of my plant does this subpart cover?
Code of Federal Regulations, 2011 CFR
2011-07-01
... in the manufacture of product chlorine, product caustic, and by-product hydrogen at a plant site. This subpart covers mercury emissions from by-product hydrogen streams, end box ventilation system vents, and fugitive emission sources associated with cell rooms, hydrogen systems, caustic systems, and...
40 CFR 63.8184 - What parts of my plant does this subpart cover?
Code of Federal Regulations, 2012 CFR
2012-07-01
... in the manufacture of product chlorine, product caustic, and by-product hydrogen at a plant site. This subpart covers mercury emissions from by-product hydrogen streams, end box ventilation system vents, and fugitive emission sources associated with cell rooms, hydrogen systems, caustic systems, and...
40 CFR 63.8184 - What parts of my plant does this subpart cover?
Code of Federal Regulations, 2013 CFR
2013-07-01
... in the manufacture of product chlorine, product caustic, and by-product hydrogen at a plant site. This subpart covers mercury emissions from by-product hydrogen streams, end box ventilation system vents, and fugitive emission sources associated with cell rooms, hydrogen systems, caustic systems, and...
Rye cover crop effects on nitrous oxide emissions from a corn-soybean system
USDA-ARS?s Scientific Manuscript database
Agricultural activities are a major source nitrous oxide emitted to the atmosphere. Development of management practices to reduce these emissions is needed. Non-leguminous cover crops are efficient scavengers of residual soil nitrate, but their effects on nitrous oxide emissions have not been well d...
Social Structure and Social Change in Eastern Europe.
ERIC Educational Resources Information Center
Fischer, George; Schenkel, Walter
This specialized bibliography of scholarly writings since 1945 on Eastern Europe covers the countries of Albania, Bulgaria, Czechoslovakia, Greece, Hungary, Poland, Romania, and Yugoslavia. Distinct entries number about 700 and cover works published in English in the United States and Great Britain and also sources in French and German published…
Climate and Land-Cover Change Impacts on Stream Flow in the Southwest U.S.
Vegetation change in arid and semi-arid climatic regions of the American West are a primary concern in sustaining key ecosystem services such as clean, reliable water sources for multiple uses. Land cover and climate change impacts on stream flow were investigated in a southeast ...
Operational monitoring of land-cover change using multitemporal remote sensing data
NASA Astrophysics Data System (ADS)
Rogan, John
2005-11-01
Land-cover change, manifested as either land-cover modification and/or conversion, can occur at all spatial scales, and changes at local scales can have profound, cumulative impacts at broader scales. The implication of operational land-cover monitoring is that researchers have access to a continuous stream of remote sensing data, with the long term goal of providing for consistent and repetitive mapping. Effective large area monitoring of land-cover (i.e., >1000 km2) can only be accomplished by using remotely sensed images as an indirect data source in land-cover change mapping and as a source for land-cover change model projections. Large area monitoring programs face several challenges: (1) choice of appropriate classification scheme/map legend over large, topographically and phenologically diverse areas; (2) issues concerning data consistency and map accuracy (i.e., calibration and validation); (3) very large data volumes; (4) time consuming data processing and interpretation. Therefore, this dissertation research broadly addresses these challenges in the context of examining state-of-the-art image pre-processing, spectral enhancement, classification, and accuracy assessment techniques to assist the California Land-cover Mapping and Monitoring Program (LCMMP). The results of this dissertation revealed that spatially varying haze can be effectively corrected from Landsat data for the purposes of change detection. The Multitemporal Spectral Mixture Analysis (MSMA) spectral enhancement technique produced more accurate land-cover maps than those derived from the Multitemporal Kauth Thomas (MKT) transformation in northern and southern California study areas. A comparison of machine learning classifiers showed that Fuzzy ARTMAP outperformed two classification tree algorithms, based on map accuracy and algorithm robustness. Variation in spatial data error (positional and thematic) was explored in relation to environmental variables using geostatistical interpolation techniques. Finally, the land-cover modification maps generated for three time intervals (1985--1990--1996--2000), with nine change-classes revealed important variations in land-cover gain and loss between northern and southern California study areas.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 40 Protection of Environment 13 2012-07-01 2012-07-01 false How do I know if my boat manufacturing... Pollutants for Boat Manufacturing What the Subpart Covers § 63.5692 How do I know if my boat manufacturing facility is a new source or an existing source? (a) A boat manufacturing facility is a new source if it...
Code of Federal Regulations, 2014 CFR
2014-07-01
... 40 Protection of Environment 13 2014-07-01 2014-07-01 false How do I know if my boat manufacturing... Pollutants for Boat Manufacturing What the Subpart Covers § 63.5692 How do I know if my boat manufacturing facility is a new source or an existing source? (a) A boat manufacturing facility is a new source if it...
Code of Federal Regulations, 2013 CFR
2013-07-01
... 40 Protection of Environment 13 2013-07-01 2012-07-01 true How do I know if my boat manufacturing... Pollutants for Boat Manufacturing What the Subpart Covers § 63.5692 How do I know if my boat manufacturing facility is a new source or an existing source? (a) A boat manufacturing facility is a new source if it...
Sayell, E.H.
1973-10-23
A radioisotopic heat source is described which includes a core of heat productive, radioisotopic material, an impact resistant layer of graphite surrounding said core, and a shell of iridium metal intermediate the core and the impact layer. The source may also include a compliant mat of iridium between the core and the iridium shell, as well as an outer covering of iridium metal about the entire heat source. (Official Gazette)
Predicting DNAPL Source Zone and Plume Response Using Site-Measured Characteristics
2017-05-19
FINAL REPORT Predicting DNAPL Source Zone and Plume Response Using Site- Measured Characteristics SERDP Project ER-1613 MAY 2017...Final Report 3. DATES COVERED (From - To) 2007 - 2017 4. TITLE AND SUBTITLE PREDICTING DNAPL SOURCE ZONE AND PLUME RESPONSE USING SITE- MEASURED ...historical record of concentration and head measurements , particularly in the near-source region. For each site considered, currently available data
Novel measurement technologies for ambient and combustion source aerosols
Thie presentaiton examines the chemical properties of atmospheric and combustion source aerosols. It describes the aerosol chemical fractions and the specific chemical constituents in these aerosols. The presentation will cover (i) the limitatins and benefits of hyphenated chroma...
Freshwater Biological Traits Database (Data Sources)
When EPA release the final report, Freshwater Biological Traits Database, it referenced numerous data sources that are included below. The Traits Database report covers the development of a database of freshwater biological traits with additional traits that are relevan...
The Chandra Source Catalog: Source Properties and Data Products
NASA Astrophysics Data System (ADS)
Rots, Arnold; Evans, Ian N.; Glotfelty, Kenny J.; Primini, Francis A.; Zografou, Panagoula; Anderson, Craig S.; Bonaventura, Nina R.; Chen, Judy C.; Davis, John E.; Doe, Stephen M.; Evans, Janet D.; Fabbiano, Giuseppina; Galle, Elizabeth C.; Gibbs, Danny G., II; Grier, John D.; Hain, Roger; Hall, Diane M.; Harbo, Peter N.; He, Xiang Qun (Helen); Houck, John C.; Karovska, Margarita; Kashyap, Vinay L.; Lauer, Jennifer; McCollough, Michael L.; McDowell, Jonathan C.; Miller, Joseph B.; Mitschang, Arik W.; Morgan, Douglas L.; Mossman, Amy E.; Nichols, Joy S.; Nowak, Michael A.; Plummer, David A.; Refsdal, Brian L.; Siemiginowska, Aneta L.; Sundheim, Beth A.; Tibbetts, Michael S.; van Stone, David W.; Winkelman, Sherry L.
2009-09-01
The Chandra Source Catalog (CSC) is breaking new ground in several areas. There are two aspects that are of particular interest to the users: its evolution and its contents. The CSC will be a living catalog that becomes richer, bigger, and better in time while still remembering its state at each point in time. This means that users will be able to take full advantage of new additions to the catalog, while retaining the ability to back-track and return to what was extracted in the past. The CSC sheds the limitations of flat-table catalogs. Its sources will be characterized by a large number of properties, as usual, but each source will also be associated with its own specific data products, allowing users to perform mini custom analysis on the sources. Source properties fall in the spatial (position, extent), photometric (fluxes, count rates), spectral (hardness ratios, standard spectral fits), and temporal (variability probabilities) domains, and are all accompanied by error estimates. Data products cover the same coordinate space and include event lists, images, spectra, and light curves. In addition, the catalog contains data products covering complete observations: event lists, background images, exposure maps, etc. This work is supported by NASA contract NAS8-03060 (CXC).
Dailey, Deena D; Braun, Christopher B
2011-08-01
Goldfish (Carassius auratus) were conditioned to suppress respiration to a 40-Hz vibratory source and subsequently tested for stimulus generalization to frequency, stimulus amplitude, and position (azimuth). Animals completely failed to generalize to frequencies separated by octave intervals both lesser and greater than the CS. However, they did appear to generalize weakly to an aerial loudspeaker stimulus of the same frequency (40 Hz) after conditioning with an underwater vibratory source. Animals had a gradually decreasing amount of generalization to amplitude changes, suggesting a perceptual dimension of loudness. Animals generalized largely or completely to the same underwater source presented at a range of source azimuths. When these azimuths were presented at a transect of 3 cm, some animals did show decrements in generalization, while others did not. This suggests that although azimuth may be perceived more saliently at distances closer to a dipole source, perception of position is not immediately salient in conditioned vibratory source detection. Differential responding to test stimuli located toward the head or tail suggests the presence of perceptual differences between sources that are rostral or caudal with respect to the position of the animal or perhaps the head. PsycINFO Database Record (c) 2011 APA, all rights reserved.
Addante, Richard, J.; Ranganath, Charan; Yonelinas, Andrew, P.
2012-01-01
Recollection is typically associated with high recognition confidence and accurate source memory. However, subjects sometimes make accurate source memory judgments even for items that are not confidently recognized, and it is not known whether these responses are based on recollection or some other memory process. In the current study, we measured event related potentials (ERPs) while subjects made item and source memory confidence judgments in order to determine whether recollection supported accurate source recognition responses for items that were not confidently recognized. In line with previous studies, we found that recognition memory was associated with two ERP effects: an early on-setting FN400 effect, and a later parietal old-new effect [Late Positive Component (LPC)], which have been associated with familiarity and recollection, respectively. The FN400 increased gradually with item recognition confidence, whereas the LPC was only observed for highly confident recognition responses. The LPC was also related to source accuracy, but only for items that had received a high confidence item recognition response; accurate source judgments to items that were less confidently recognized did not exhibit the typical ERP correlate of recollection or familiarity, but rather showed a late, broadly distributed negative ERP difference. The results indicate that accurate source judgments of episodic context can occur even when recollection fails. PMID:22548808
NASA Astrophysics Data System (ADS)
de Oliveira, Lília M.; Santos, Nádia A. P.; Maillard, Philippe
2013-10-01
Non-point source pollution (NPSP) is perhaps the leading cause of water quality problems and one of the most challenging environmental issues given the difficulty of modeling and controlling it. In this article, we applied the Manning equation, a hydraulic concept, to improve models of non-point source pollution and determine its influence as a function of slope - land cover roughness for runoff to reach the stream. In our study the equation is somewhat taken out of its usual context to be applies to the flow of an entire watershed. Here a digital elevation model (DEM) from the SRTM satellite was used to compute the slope and data from the RapidEye satellite constellation was used to produce a land cover map later transformed into a roughness surface. The methodology is applied to a 1433 km2 watershed in Southeast Brazil mostly covered by forest, pasture, urban and wetlands. The model was used to create slope buffer of varying width in which the proportions of land cover and roughness coefficient were obtained. Next we correlated these data, through regression, with four water quality parameters measured in situ: nitrate, phosphorous, faecal coliform and turbidity. We compare our results with the ones obtained by fixed buffer. It was found that slope buffer outperformed fixed buffer with higher coefficients of determination up to 15%.
Assessing winter cover crop nutrient uptake efficiency using a water quality simulation model
Yeo, In-Young; Lee, Sangchui; Sadeghi, Ali M.; Beeson, Peter C.; Hively, W. Dean; McCarty, Greg W.; Lang, Megan W.
2013-01-01
Winter cover crops are an effective conservation management practice with potential to improve water quality. Throughout the Chesapeake Bay Watershed (CBW), which is located in the Mid-Atlantic US, winter cover crop use has been emphasized and federal and state cost-share programs are available to farmers to subsidize the cost of winter cover crop establishment. The objective of this study was to assess the long-term effect of planting winter cover crops at the watershed scale and to identify critical source areas of high nitrate export. A physically-based watershed simulation model, Soil and Water Assessment Tool (SWAT), was calibrated and validated using water quality monitoring data and satellite-based estimates of winter cover crop species performance to simulate hydrological processes and nutrient cycling over the period of 1991–2000. Multiple scenarios were developed to obtain baseline information on nitrate loading without winter cover crops planted and to investigate how nitrate loading could change with different winter cover crop planting scenarios, including different species, planting times, and implementation areas. The results indicate that winter cover crops had a negligible impact on water budget, but significantly reduced nitrate leaching to groundwater and delivery to the waterways. Without winter cover crops, annual nitrate loading was approximately 14 kg ha−1, but it decreased to 4.6–10.1 kg ha−1 with winter cover crops resulting in a reduction rate of 27–67% at the watershed scale. Rye was most effective, with a potential to reduce nitrate leaching by up to 93% with early planting at the field scale. Early planting of winter cover crops (~30 days of additional growing days) was crucial, as it lowered nitrate export by an additional ~2 kg ha−1 when compared to late planting scenarios. The effectiveness of cover cropping increased with increasing extent of winter cover crop implementation. Agricultural fields with well-drained soils and those that were more frequently used to grow corn had a higher potential for nitrate leaching and export to the waterways. This study supports the effective implement of winter cover crop programs, in part by helping to target critical pollution source areas for winter cover crop implementation.
Mercury emission to the atmosphere from municipal solid waste landfills: A brief review
NASA Astrophysics Data System (ADS)
Tao, Zhengkai; Dai, Shijin; Chai, Xiaoli
2017-12-01
Municipal solid waste (MSW) landfill is regarded as an important emission source of atmospheric mercury (Hg), which is associated with potential health and environmental risks, as outlined by the Minamata Convention on Hg. This review presents the current state of knowledge with regards to landfill Hg sources, Hg levels in MSW and cover soils, Hg emission to the atmosphere, available Hg biogeochemical transformations, research methods for Hg emission, and important areas for future research. In addition, strategies for controlling landfill Hg emissions are considered, including reducing the Hg load in landfill and in situ controls. These approaches mainly focus on Hg source reduction, Hg recycling programs, public education, and in situ technology such as timely soil cover, vegetation, and end-of-pipe technology for controlling Hg emission from landfill gas.
SOURCES AND TRANSFORMATIONS OF NITROGEN, CARBON, AND PHOSPHORUS IN THE POTOMAC RIVER ESTUARY
NASA Astrophysics Data System (ADS)
Pennino, M. J.; Kaushal, S.
2009-12-01
Global transport of nitrogen (N), carbon (C), and phosphorus (P) in river ecosystems has been dramatically altered due to urbanization. We examined the capacity of a major tributary of the Chesapeake Bay, the Potomac River, to transform carbon, nitrogen, and phosphorus inputs from the world’s largest advanced wastewater treatment facility (Washington D.C. Water and Sewer Authority). Surface water and effluent samples were collected along longitudinal transects of the Potomac River seasonally and compared to long-term interannual records of carbon, nitrogen, and phosphorus. Water samples from seasonal longitudinal transects were analyzed for dissolved organic and inorganic nitrogen and phosphorus, total organic carbon, and particulate carbon, nitrogen, and phosphorus. The source and quality of organic matter was characterized using fluorescence spectroscopy, excitation emission matrices (EEMs), and PARAFAC modeling. Sources of nitrate were tracked using stable isotopes of nitrogen and oxygen. Along the river network stoichiometric ratios of C, N, and P were determined across sites and related to changes in flow conditions. Land use data and historical water chemistry data were also compared to assess the relative importance of non-point sources from land-use change versus point-sources of carbon, nitrogen, and phosphorus. Preliminary data from EEMs suggested that more humic-like organic matter was important above the wastewater treatment plant, but more protein-like organic matter was present below the treatment plant. Levels of nitrate and ammonia showed increases within the vicinity of the wastewater treatment outfall, but decreased rapidly downstream, potentially indicating nutrient uptake and/or denitrification. Phosphate levels decreased gradually along the river with a small increase near the wastewater treatment plant and a larger increase and decrease further downstream near the high salinity zone. Total organic carbon levels show a small decrease downstream. Ecological stoichiometric ratios along the river indicate increases in C/N ratios downstream, but no corresponding trend with C/P ratios. The N/P ratios increased directly below the treatment plant and then decreased gradually downstream. The C/N/P ratios remained level until the last two sampling stations within 20 miles of the Chesapeake Bay, where there is a large increase. Despite large inputs, there may be large variations in sources and ecological stoichiometry along rivers and estuaries, and knowledge of these transformations will be important in predicting changes in the amounts, forms, and stoichiometry of nutrient loads to coastal waters.
This is a 2016 table that looks at oil and natural gas industry site types and lists the applicable rules for the 2012 and 2016 new source performance standards (NSPS) and Volatile Organic Compounds (VOC) rules.
ERIC Educational Resources Information Center
Council of Europe, Strasbourg (France). Documentation Center for Education in Europe.
A survey was conducted to update a series of documents published by the Council of Europe in 1975. This survey covers the following countries: Austria, Belgium (Dutch-speaking area), Cyprus, Denmark, Finland, Iceland, Ireland, Liechtenstein, Luxembourg, Switzerland, and the United Kingdom. For each country, details are given concerning sources of…
Creating a Project on Difference Equations with Primary Sources: Challenges and Opportunities
ERIC Educational Resources Information Center
Ruch, David
2014-01-01
This article discusses the creation of a student project about linear difference equations using primary sources. Early 18th-century developments in the area are outlined, focusing on efforts by Abraham De Moivre (1667-1754) and Daniel Bernoulli (1700-1782). It is explained how primary sources from these authors can be used to cover material…
Energy: A Guide to Organizations and Information Resources in the United States.
ERIC Educational Resources Information Center
Center for California Public Affairs, Claremont.
A central source of information on the key organizations concerned with energy in the United States has been compiled. Chapter 2 covers organizations involved with broad questions of energy policy; Chapters 2-6 describe organizations having to do with sources of energy: oil, natural gas, coal, water power, nuclear fission, and alternate sources;…
Field based plastic contamination sensing
USDA-ARS?s Scientific Manuscript database
The United States has a long-held reputation of being a dependable source of high quality, contaminant-free cotton. Recently, increased incidence of plastic contamination from sources such as shopping bags, vegetable mulch, surface irrigation tubing, and module covers has threatened the reputation o...
NASA Technical Reports Server (NTRS)
Wahlen, Martin
1994-01-01
The topics covered include the following: biogenic methane studies; forest soil methane uptake; rice field methane sources; atmospheric measurements; stratospheric samples; Antarctica; California; and Germany.
40 CFR 63.2440 - What parts of my plant does this subpart cover?
Code of Federal Regulations, 2014 CFR
2014-07-01
...? (a) This subpart applies to each miscellaneous organic chemical manufacturing affected source. (b) The miscellaneous organic chemical manufacturing affected source is the facilitywide collection of... CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Miscellaneous Organic...
40 CFR 63.2440 - What parts of my plant does this subpart cover?
Code of Federal Regulations, 2012 CFR
2012-07-01
...? (a) This subpart applies to each miscellaneous organic chemical manufacturing affected source. (b) The miscellaneous organic chemical manufacturing affected source is the facilitywide collection of... CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Miscellaneous Organic...
40 CFR 63.2440 - What parts of my plant does this subpart cover?
Code of Federal Regulations, 2013 CFR
2013-07-01
...? (a) This subpart applies to each miscellaneous organic chemical manufacturing affected source. (b) The miscellaneous organic chemical manufacturing affected source is the facilitywide collection of... CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Miscellaneous Organic...
ERIC Educational Resources Information Center
Burke, Arvid J.; Burke, Mary A.
After a summary of background knowledge useful in searching for information, the authors cover extensively the sources available to the researcher interested in locating educational data or conducting a search of bibliographic materials. They list reference books, dictionaries, almanacs, yearbooks, subject matter summaries; and sources for…
Samarium-145 and its use as a radiation source
Fairchild, Ralph G.; Laster, Brenda H.; Packer, Samuel
1989-09-05
The present invention covers a new radiation source, samarium-145, with radiation energies slightly above those of I-125 and a half-life of 340 days. The samarium-145 source is produced by neutron irradiation of SM-144. This new source is useful as the implanted radiation source in photon activation therapy of malignant tumors to activate the stable I-127 contained in the IdUrd accumulated in the tumor, causing radiation sensitization and Auger cascades that irreperably damage the tumor cells. This new source is also useful as a brachytherapy source.
Samarium-145 and its use as a radiation source
Fairchild, Ralph G.; Laster, Brenda H.; Packer, Samuel
1989-01-01
The present invention covers a new radiation source, samarium-145, with radiation energies slightly above those of I-125 and a half-life of 340 days. The samarium-145 source is produced by neutron irradiation of SM-144. This new source is useful as the implanted radiation source in photon activation therapy of malignant tumors to activate the stable I-127 contained in the IdUrd accumulated in the tumor, causing radiation sensitization and Auger cascades that irreperably damage the tumor cells. This new source is also useful as a brachytherapy source.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 40 Protection of Environment 12 2011-07-01 2009-07-01 true How do I know if my boat manufacturing... AIR POLLUTANTS FOR SOURCE CATEGORIES National Emission Standards for Hazardous Air Pollutants for Boat Manufacturing What the Subpart Covers § 63.5692 How do I know if my boat manufacturing facility is a new source...
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 12 2010-07-01 2010-07-01 true How do I know if my boat manufacturing... AIR POLLUTANTS FOR SOURCE CATEGORIES National Emission Standards for Hazardous Air Pollutants for Boat Manufacturing What the Subpart Covers § 63.5692 How do I know if my boat manufacturing facility is a new source...
Organic supplemental nitrogen sources for field corn production after a hairy vetch cover crop
USDA-ARS?s Scientific Manuscript database
The combined use of legume cover crops and animal byproduct organic amendments could provide agronomic and environmental benefits to organic farmers by increasing corn grain yield while optimizing N and P inputs. To test this hypothesis we conducted a two-year field study and a laboratory soil incu...
5 CFR 890.1104 - Notification by agency.
Code of Federal Regulations, 2014 CFR
2014-01-01
... requirements for being considered a covered family member, the employing office must notify the child of his or... notification by the child, another family member, or any other source that the child no longer meets the requirements for being considered a covered family member. (c)(1) In the case of a former spouse who is...
Inflatable O-ring seal would ease closing of hatch cover plate
NASA Technical Reports Server (NTRS)
Neary, K. J.
1966-01-01
Inflatable O-ring seal provides positive sealing means that does not require the manual exertion of a large compressive force during opening or closing of a rotary-type hatch cover plate. The O-ring is deflated during opening and closing and inflated after closure by a gas pressure source.
40 CFR 35.101 - Environmental programs covered by the subpart.
Code of Federal Regulations, 2013 CFR
2013-07-01
...) of the Safe Drinking Water Act). (5) Underground water source protection (section 1443(b) of the Safe... 104(b)(3) of the Clean Water Act). (17) Wetlands development grants program (section 104(b)(3) of the... 40 Protection of Environment 1 2013-07-01 2013-07-01 false Environmental programs covered by the...
40 CFR 35.101 - Environmental programs covered by the subpart.
Code of Federal Regulations, 2014 CFR
2014-07-01
...) of the Safe Drinking Water Act). (5) Underground water source protection (section 1443(b) of the Safe... 104(b)(3) of the Clean Water Act). (17) Wetlands development grants program (section 104(b)(3) of the... 40 Protection of Environment 1 2014-07-01 2014-07-01 false Environmental programs covered by the...
40 CFR 35.101 - Environmental programs covered by the subpart.
Code of Federal Regulations, 2012 CFR
2012-07-01
...) of the Safe Drinking Water Act). (5) Underground water source protection (section 1443(b) of the Safe... 104(b)(3) of the Clean Water Act). (17) Wetlands development grants program (section 104(b)(3) of the... 40 Protection of Environment 1 2012-07-01 2012-07-01 false Environmental programs covered by the...
Combining accuracy assessment of land-cover maps with environmental monitoring programs
Stephen V. Stehman; Raymond L. Czaplewski; Sarah M. Nusser; Limin Yang; Zhiliang Zhu
2000-01-01
A scientifically valid accuracy assessment of a large-area, land-cover map is expensive. Environmental monitoring programs offer a potential source of data to partially defray the cost of accuracy assessment while still maintaining the statistical validity. In this article, three general strategies for combining accuracy assessment and environmental monitoring...
The 14,582 km2 Neuse River Basin in North Carolina was characterized based on a user defined land-cover (LC) classification system developed specifically to support spatially explicit, non-point source nitrogen allocation modeling studies. Data processing incorporated both spect...
Minor Maintenance. A Resource Manual for Custodians.
ERIC Educational Resources Information Center
Florida State Dept. of Education, Tallahassee.
Areas of minor maintenance covered by this manual are--(1) electrical, (2) carpentry, (3) plumbing, (4) painting, and (5) masonry. Each area is defined, tools and equipment for maintenance are listed, and the job procedure is given. The description of electrical work also covers sources of electricity and power transmission. The description of…
USDA-ARS?s Scientific Manuscript database
The estimation of spatial patterns in surface fluxes from aircraft observations poses several challenges in presence of heterogeneous land cover. In particular, the effects of turbulence on scalar transport and the different behavior of passive (e.g. moisture) versus active (e.g. temperature) scalar...
Manufacturing in Space: (It's Getting off the Ground!) Resources in Technology.
ERIC Educational Resources Information Center
Technology Teacher, 1988
1988-01-01
Discusses current issues and work on the planned manufacturing Space Station. Such topics as human resources, energy sources, and types of products to be manufactured in space are covered. The possibility of mining other planets for raw materials is considered. Student activities and a quiz covering the article are included. (CH)
USDA-ARS?s Scientific Manuscript database
Accurate and timely spatial predictions of vegetation cover from remote imagery are an important data source for natural resource management. High-quality in situ data are needed to develop and validate these products. Point-intercept sampling techniques are a common method for obtaining quantitativ...
Boyle, Kerry E.; Monaco, Hilary; van Ditmarsch, Dave; Deforet, Maxime; Xavier, Joao B.
2015-01-01
Many unicellular organisms live in multicellular communities that rely on cooperation between cells. However, cooperative traits are vulnerable to exploitation by non-cooperators (cheaters). We expand our understanding of the molecular mechanisms that allow multicellular systems to remain robust in the face of cheating by dissecting the dynamic regulation of cooperative rhamnolipids required for swarming in Pseudomonas aeruginosa. We combine mathematical modeling and experiments to quantitatively characterize the integration of metabolic and population density signals (quorum sensing) governing expression of the rhamnolipid synthesis operon rhlAB. The combined computational/experimental analysis reveals that when nutrients are abundant, rhlAB promoter activity increases gradually in a density dependent way. When growth slows down due to nutrient limitation, rhlAB promoter activity can stop abruptly, decrease gradually or even increase depending on whether the growth-limiting nutrient is the carbon source, nitrogen source or iron. Starvation by specific nutrients drives growth on intracellular nutrient pools as well as the qualitative rhlAB promoter response, which itself is modulated by quorum sensing. Our quantitative analysis suggests a supply-driven activation that integrates metabolic prudence with quorum sensing in a non-digital manner and allows P. aeruginosa cells to invest in cooperation only when the population size is large enough (quorum sensing) and individual cells have enough metabolic resources to do so (metabolic prudence). Thus, the quantitative description of rhlAB regulatory dynamics brings a greater understating to the regulation required to make swarming cooperation stable. PMID:26102206
Development of an Independent Global Land Cover Validation Dataset
NASA Astrophysics Data System (ADS)
Sulla-Menashe, D. J.; Olofsson, P.; Woodcock, C. E.; Holden, C.; Metcalfe, M.; Friedl, M. A.; Stehman, S. V.; Herold, M.; Giri, C.
2012-12-01
Accurate information related to the global distribution and dynamics in global land cover is critical for a large number of global change science questions. A growing number of land cover products have been produced at regional to global scales, but the uncertainty in these products and the relative strengths and weaknesses among available products are poorly characterized. To address this limitation we are compiling a database of high spatial resolution imagery to support international land cover validation studies. Validation sites were selected based on a probability sample, and may therefore be used to estimate statistically defensible accuracy statistics and associated standard errors. Validation site locations were identified using a stratified random design based on 21 strata derived from an intersection of Koppen climate classes and a population density layer. In this way, the two major sources of global variation in land cover (climate and human activity) are explicitly included in the stratification scheme. At each site we are acquiring high spatial resolution (< 1-m) satellite imagery for 5-km x 5-km blocks. The response design uses an object-oriented hierarchical legend that is compatible with the UN FAO Land Cover Classification System. Using this response design, we are classifying each site using a semi-automated algorithm that blends image segmentation with a supervised RandomForest classification algorithm. In the long run, the validation site database is designed to support international efforts to validate land cover products. To illustrate, we use the site database to validate the MODIS Collection 4 Land Cover product, providing a prototype for validating the VIIRS Surface Type Intermediate Product scheduled to start operational production early in 2013. As part of our analysis we evaluate sources of error in coarse resolution products including semantic issues related to the class definitions, mixed pixels, and poor spectral separation between classes.
Changes in Landscape Greenness and Climatic Factors over ...
Monitoring and quantifying changes in vegetation cover over large areas using remote sensing can be achieved using the Normalized Difference Vegetation Index (NDVI), an indicator of greenness. However, distinguishing gradual shifts in NDVI (e.g. climate change) versus direct and rapid changes (e.g., fire, land development) is challenging as changes can be confounded by time-dependent patterns, and variation associated with climatic factors. In the present study we leveraged a method, that we previously developed for a pilot study, to address these confounding factors by evaluating NDVI change using autoregression techniques that compare results from univariate (NDVI vs. time) and multivariate analyses (NDVI vs. time and climatic factors) for ~7,660,636 1-km2 pixels comprising the 48 contiguous states of the USA, over a 25-year period (1989−2013). NDVI changed significantly for 48% of the nation over the 25-year in the univariate analyses where most significant trends (85%) indicated an increase in greenness over time. By including climatic factors in the multivariate analyses of NDVI over time, the detection of significant NDVI trends increased to 53% (an increase of 5%). Comparisons of univariate and multivariate analyses for each pixel showed that less than 4% of the pixels had a significant NDVI trend attributable to gradual climatic changes while the remainder of pixels with a significant NDVI trend indicated that changes were due to direct factors. Whi
NASA Astrophysics Data System (ADS)
Streit, Kathrin; Bennett, Sarah A.; Van Dover, Cindy L.; Coleman, Max
2015-06-01
Hydrothermal vents harbor ecosystems mostly decoupled from organic carbon synthesized with the energy of sunlight (photosynthetic carbon source) but fueled instead by oxidation of reduced compounds to generate a chemosynthetic carbon source. Our study aimed to disentangle photosynthetic and chemosynthetic organic carbon sources for the shrimp species Rimicaris hybisae, a primary consumer presumed to obtain its organic carbon mainly from ectosymbiotic chemoautotrophic bacteria living on its gill cover membrane. To provide ectosymbionts with ideal conditions for chemosynthesis, these shrimp live in dense clusters around vent chimneys; they are, however, also found sparsely distributed adjacent to diffuse vent flows, where they might depend on alternative food sources. Densely and sparsely distributed shrimp were sampled and dissected into abdominal tissue and gill cover membrane, covered with ectosymbiotic bacteria, at two hydrothermal vent fields in the Mid-Cayman rise that differ in vent chemistry. Fatty acids (FA) were extracted from shrimp tissues and their carbon isotopic compositions assessed. The FA data indicate that adult R. hybisae predominantly rely on bacteria for their organic carbon needs. Their FA composition is dominated by common bacterial FA of the n7 family (~41%). Bacterial FA of the n4 FA family are also abundant and found to constitute good biomarkers for gill ectosymbionts. Sparsely distributed shrimp contain fractions of n4 FA in gill cover membranes ~4% lower than densely packed ones (~18%) and much higher fractions of photosynthetic FA in abdominal tissues, ~4% more (compared with 1.6%), suggesting replacement of ectosymbionts along with exoskeletons (molt), while they take up alternative diets of partly photosynthetic organic carbon. Abdominal tissues also contain photosynthetic FA from a second source taken up presumably during an early dispersal phase and still present to c. 3% in adult shrimp. The contribution of photosynthetic carbon to the FA pool of adult R. hybisae is, however, overall small (max. 8%). Significant differences in carbon isotopic values of chemosynthetically derived FA between vent fields suggest that different dominant C fixation pathways are being used.
Validation of national land-cover characteristics data for regional water-quality assessment
Zelt, Ronald B.; Brown, Jesslyn F.; Kelley, M.S.
1995-01-01
Land-cover information is used routinely to support the interpretation of water-quality data. The Prototype 1990 Conterminous US Land Cover Characteristics Data Set, developed primarily from Advanced Very High Resolution Radiometer (AVHRR) data, was made available to the US Geological Survey's National Water-Quality Assessment (NAWQA) Program. The study described in this paper explored the utility of the 1990 national data set for developing quantitative estimates of the areal extent of principal land-cover types within large areal units. Land-cover data were collected in 1993 at 210 sites in the Central Nebraska Basins, one of the NAWQA study units. Median percentage-corn estimates for each sampling stratum wre used to produce areally weighted estimates of the percentage-corn cover for hydrologic units. Comparison of those areal estimates with an independent source of 1992 land-cover data showed good agreement. -Authors
Fronstin, P
2001-12-01
This Issue Brief provides summary data on the insured and uninsured populations in the nation and in each state. It discusses the characteristics most closely related to an individual's health insurance status. Based on EBRI estimates from the March 2001 Current Population Survey (CPS), it represents 2000 data--the most recent available. Between 1999 and 2000, the percentage of Americans with health insurance increased: 84.1 percent of nonelderly Americans were covered by some form of health insurance in 2000, up from 83.8 percent in 1999. The percentage of nonelderly Americans without health insurance coverage declined from 16.2 percent in 1999 to 15.9 percent in 2000, continuing a trend that started between 1998 and 1999. The main reason for the decline in the number of uninsured Americans was the strong economy and low unemployment. Between 1999 and 2000, the percentage of nonelderly Americans covered by employment-based health insurance increased from 66.6 percent to 67.3 percent, continuing a longer-term trend that started between 1993 and 1994. In 2000, 34.3 million Americans received health insurance from public programs, and an additional 16.1 million purchased it directly from an insurer. More than 25 million Americans participated in Medicaid or the State Children's Health Insurance Program, and 6.1 million received their health insurance through the Tricare and CHAMPVA programs and other government programs designed to provide coverage for retired military members and their families. Even though the number and percentage of uninsured declined substantially between 1998 and 2000, more than 38 million Americans remain uninsured. While an increasing percentage of Americans were being covered by employment-based health plans, this trend may not continue because of the combined re-emergence of health care cost inflation and the weak economy. As long as the economy is strong and unemployment is low, employment-based health insurance coverage will expand and the uninsured will decline gradually. However, the combination of the current weak economy and the rising cost of providing health benefits will likely result in more Americans without health insurance coverage. Should the uninsured remain unchanged and continue to represent 15.9 percent of the nonelderly population, 40 million would be uninsured by 2005. If the uninsured represented 25 percent of the population, 63 million would be uninsured in 2005 and 65 million nonelderly Americans would be uninsured by 2010.
2MASS Extended Source Catalog: Overview and Algorithms
NASA Technical Reports Server (NTRS)
Jarrett, T.; Chester, T.; Cutri, R.; Schneider, S.; Skrutskie, M.; Huchra, J.
1999-01-01
The 2 Micron All-Sky Survey (2MASS)will observe over one-million galaxies and extended Galactic sources covering the entire sky at wavelenghts between 1 and 2 m. Most of these galaxies, from 70 to 80%, will be newly catalogued objetcs.
Statistical Sources for Health Science Librarians.
ERIC Educational Resources Information Center
Weise, Frieda
This continuing education course syllabus presents information on the collection of vital and health statistics, lists of agencies or organizations involved in statistical collection and/or dissemination, annotated bibliographies of statistical sources, and guidelines for accessing statistical information. Topics covered include: (1) the reporting…
40 CFR 63.2440 - What parts of my plant does this subpart cover?
Code of Federal Regulations, 2011 CFR
2011-07-01
... CATEGORIES National Emission Standards for Hazardous Air Pollutants: Miscellaneous Organic Chemical... subpart applies to each miscellaneous organic chemical manufacturing affected source. (b) The miscellaneous organic chemical manufacturing affected source is the facilitywide collection of MCPU and heat...
40 CFR 63.2440 - What parts of my plant does this subpart cover?
Code of Federal Regulations, 2010 CFR
2010-07-01
... CATEGORIES National Emission Standards for Hazardous Air Pollutants: Miscellaneous Organic Chemical... subpart applies to each miscellaneous organic chemical manufacturing affected source. (b) The miscellaneous organic chemical manufacturing affected source is the facilitywide collection of MCPU and heat...
Getting the lead out: understanding risks in the distribution system
This presentation discusses the importance of the water distribution system as a component of the source-to-tap continuum in public health protection. Issues covered include: understanding source water quality changes and their impacts throughout the system; use of mitigation me...
THE ASSOCIATION OF LAND USE/LAND COVER AND NUTRIENT LEVELS IN MARYLAND STREAMS
Anthropogenic nonpoint sources of nutrients are known to cause accelerated eutrophication of estuaries. The Chesapeake Bay is one of the world's largest estuaries exhibiting the eutrophication problem caused by pollution from various land use activities. The sources contributing ...
Cornelius, Craig W; Heinrichs, Leroy; Youngblood, Patricia; Dev, Parvati
2007-01-01
Stanford University Medical Media and Information Technologies's technical workshop "Prototyping of Surgical Simulators using Open Source Simulation Software" was held in August 2006 at Stanford University. The objectives, program, and topics covered are presented in this short report.
Stenting complex aorta aneurysms with the Cardiatis multilayer flow modulator: first impressions.
Debing, E; Aerden, D; Gallala, S; Vandenbroucke, F; Van den Brande, P
2014-06-01
Our aim was to assess the feasibility and efficacy of the Cardiatis multilayer flow modulator in the treatment of complex aorta aneurysms. This is a single-center prospective registry. Six patients (4 males and 2 females; mean age 74 years) with complex aorta aneurysms (unsuitable for endovascular repair with standard, fenestrated, or branched stent grafts) were treated with the Cardiatis multilayer flow modulator. Clinical success was 100%. Median follow-up was 10 months. One patient died the third postoperative day due to aneurysm rupture. Four aneurysms were completely thrombosed between 1 and 6 months after the procedure. The patency of the covered aortic branches was 100%. At 6 months, the sac volume was decreased in two patients, increased in two patients and remains stable in one patient. There were no stent migrations, retractions, thrombosis, fractures, or reinterventions. The device preserves flow into the covered aortic branches and completed aneurysm thrombosis occurs gradually; however, the stent did not prevent rupture immediately after the implantation. Longer follow-up is mandatory to prove the efficacy of this technology. Copyright © 2014 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.
A Review of Glass-Ionomer Cements for Clinical Dentistry
Sidhu, Sharanbir K.; Nicholson, John W.
2016-01-01
This article is an updated review of the published literature on glass-ionomer cements and covers their structure, properties and clinical uses within dentistry, with an emphasis on findings from the last five years or so. Glass-ionomers are shown to set by an acid-base reaction within 2–3 min and to form hard, reasonably strong materials with acceptable appearance. They release fluoride and are bioactive, so that they gradually develop a strong, durable interfacial ion-exchange layer at the interface with the tooth, which is responsible for their adhesion. Modified forms of glass-ionomers, namely resin-modified glass-ionomers and glass carbomer, are also described and their properties and applications covered. Physical properties of the resin-modified glass-ionomers are shown to be good, and comparable with those of conventional glass-ionomers, but biocompatibility is somewhat compromised by the presence of the resin component, 2 hydroxyethyl methacrylate. Properties of glass carbomer appear to be slightly inferior to those of the best modern conventional glass-ionomers, and there is not yet sufficient information to determine how their bioactivity compares, although they have been formulated to enhance this particular feature. PMID:27367737
Development of a super-pressure balloon with a diamond-shaped net
NASA Astrophysics Data System (ADS)
Saito, Y.; Iijima, I.; Matsuzaka, Y.; Matsushima, K.; Tanaka, S.; Kajiwara, K.; Shimadu, S.
2014-10-01
The essential reason of the lobed-pumpkin shaped super-pressure balloon to withstand against the high pressure is that the local curvature of the balloon film is kept small. Recently, it has been found that the small local curvature can also be obtained if the balloon is covered by a diamond-shaped net with a vertically elongated shape. The development of the super-pressure balloon using this method was started from a 3-m balloon with a polyethylene film covered by a net using Kevlar ropes. The ground inflation test showed the expected high burst pressure. Then, a 6-m and a 12-m balloon using a polyethylene film and a net using the Vectran were developed and stable deployment was checked through the ground inflation tests. The flight test of a 3000 m3 balloon was performed in 2013 and shown to resist a pressure of at least 400 Pa. In the future, after testing a new design to relax a possible stress concentration around the polar area, test flights of scaled balloons will be performed gradually enlarging their size. The goal is to launch a 300,000 m3 super-pressure balloon.
Late Cenozoic History of the Genus Micromys (Mammalia, Rodentia) in Central Europe
Horáček, Ivan; Knitlová, Markéta; Wagner, Jan; Kordos, László; Nadachowski, Adam
2013-01-01
Molecular phylogeography suggests that Micromys minutus, the sole extant species of the genus, colonized its extensive range quite recently, during the Late Pleistocene-Holocene period. Rich Pliocene and Pleistocene fossil records both from Europe and China suggest rather continuous and gradual in situ phenotype rearrangements from the Pliocene to the Recent periods. To elucidate the discrepancy we reexamined a considerable part of the European fossil record of the genus (14 sites from MN15 to Q3, 0.4–4.2 Ma, including the type series of M. preaminutus from MN15 Csarnóta 2), analyzed them with the aid of detailed morphometric comparisons, and concluded that: (a) The European Pliocene form, M. praeminutus, differs significantly from the extant species; (b) it exhibits a broad phenotypic variation covering the presumptive diagnostic characters of MN16 M. caesaris; (c) despite having smaller dimensions, the Early and Middle Pleistocene forms (MN17-Q3, 2.6–0.4 Ma) seem to be closer to M. praeminutus than to the extant species; (d) the extinction of M. praeminutus during Q3 and the re-occupation of its niche by the recent expansion of M. minutus from E-European – C Asiatic sources (suggested by phylogeographic hypotheses) cannot be excluded. Discussing interpretations of the phylogenetic past of the genus we emphasize the distinct history of the West Palearctic clade (Late Miocene-Early Pleistocene) terminating with M. praeminutus and the East Asiatic clade (chalceus, tedfordi, minutus), and the possible identity of the Western clade with the Late Miocene genus Parapodemus. PMID:23671605
Estimation of child vaccination coverage at state and national levels in India
Gupta, Satish; Kumar, Rakesh; Haldar, Pradeep; Sethi, Raman; Bahl, Sunil
2016-01-01
Abstract Objective To review the data, for 1999–2013, on state-level child vaccination coverage in India and provide estimates of coverage at state and national levels. Methods We collated data from administrative reports, population-based surveys and other sources and used them to produce annual estimates of vaccination coverage. We investigated bacille Calmette–Guérin vaccine, the first and third doses of vaccine against diphtheria, tetanus and pertussis, the third dose of oral polio vaccine and the first dose of vaccine against measles. We obtained relevant data covering the period 1999–2013 for each of 16 states and territories and the period 2001–2013 for the state of Jharkhand – which was only created in 2000. We aggregated the resultant state-level estimates, using a population-weighted approach, to give national values. Findings For each of the vaccinations we investigated, about half of the 253 estimates of annual coverage at state level that we produced were based on survey results. The rest were based on interpolation between – or extrapolation from – so-called anchor points or, more rarely, on administrative data. Our national estimates indicated that, for each of the vaccines we investigated, coverage gradually increased between 1999 and 2010 but then levelled off. Conclusion The delivery of routine vaccination services to Indian children appears to have improved between 1999 and 2013. There remains considerable scope to improve the recording and reporting of childhood vaccination coverage in India and regular systematic reviews of the coverage data are recommended. PMID:27843162
Semiarid ethnoagroforestry management: Tajos in the Sierra Gorda, Guanajuato, Mexico.
Hoogesteger van Dijk, Vincent M; Casas, Alejandro; Moreno-Calles, Ana Isabel
2017-06-12
The semi-arid environments harbor nearly 40% of biodiversity, and half of indigenous cultures of Mexico. Thousands of communities settled in these areas depend on agriculture and using wild biodiversity for their subsistence. Water, soil, and biodiversity management strategies are therefore crucial for people's life. The tajos, from Sierra Gorda, are important, poorly studied, biocultural systems established in narrow, arid alluvial valleys. The systems are constructed with stone-walls for capturing sediments, gradually creating fertile soils in terraces suitable for agriculture in places where it would not be possible. We analyzed biocultural, ecological, economic and technological relevance of the artificial oasis-like tajos, hypothesizing their high capacity for maintaining agricultural and wild biodiversity while providing resources to people. We conducted our research in three sections of the Mezquital-Xichú River, in three communities of Guanajuato, Mexico. Agroforestry management practices were documented through semi-structured and in-depth qualitative interviews. Vegetation composition of local forests and that maintained in tajos was sampled and compared. Tajos harbor high agrobiodiversity, including native varieties of maize and beans, seven secondary crops, 47 native and 25 introduced perennial plant species. Perennial plants cover on average 26.8% of the total surface of plots. Tajos provide nearly 70% of the products required by households' subsistence and are part of their cultural identity. Tajos are heritage of TEK and land management forms of pre-Columbian Mexican and Mediterranean agricultural techniques, adapting and integrating modern agricultural practices. Tajos are valuable biocultural systems adapted to local semiarid conditions and sources of technology for similar areas of the World.
NASA Astrophysics Data System (ADS)
Bowman, Dan; Korjenkov, Andrey; Porat, Naomi; Czassny, Birka
2004-11-01
The Tien Shan is a most active intracontinental mountain-building range with abundant Quaternary fault-related folding. In order to improve our understanding of Quaternary intermontane basin deformation, we investigated the intermontane Issyk-Kul Lake area, an anticline that was up-warped through the piedmont cover, causing partitioning of the alluvial fan veneer. To follow the morphological scenario during the warping process, we relied on surface-exposed and trenched structures and on alluvial fans and bajadas as reference surfaces. We used air photos and satellite images to analyze the spatial-temporal morphological record and determined the age of near surface sediments by luminescence dating. We demonstrate that the up-warped Ak-Teke hills are a thrust-generated subdued anticline with strong morphological asymmetry which results from the coupling of the competing processes of up-warp and erosional feedback. The active creeks across the up-warped anticline indicate that the antecedent drainage system kept pace with the rate of uplift. The rivers which once sourced the piedmont, like the Toru-Aygyr, Kultor and the Dyuresu, became deeply entrenched and gradually transformed the study area into an abandoned morphological surface. The up-warp caused local lateral drainage diversion in front of the northern backlimb and triggered the formation of a dendritic drainage pattern upfan. Luminescence dating suggest that the period of up-warp and antecedent entrenchment started after 157 ka. The morphologically mature study area demonstrates the response of fluvial systems to growing folds on piedmont areas, induced by a propagating frontal fold at a thrust belt edge, following shortening.
Aromatic acids in an Arctic ice core from Svalbard: a proxy record of biomass burning
NASA Astrophysics Data System (ADS)
Grieman, Mackenzie M.; Aydin, Murat; Isaksson, Elisabeth; Schwikowski, Margit; Saltzman, Eric S.
2018-05-01
This study presents vanillic acid and para-hydroxybenzoic acid levels in an Arctic ice core from Lomonosovfonna, Svalbard covering the past 800 years. These aromatic acids are likely derived from lignin combustion in wildfires and long-range aerosol transport. Vanillic and para-hydroxybenzoic acid are present throughout the ice core, confirming that these compounds are preserved on millennial timescales. Vanillic and para-hydroxybenzoic acid concentrations in the Lomonosovfonna ice core ranged from below the limits of detection to 0.2 and 0.07 ppb, respectively (1 ppb = 1000 ng L-1). Vanillic acid levels are high (maximum of 0.1 ppb) from 1200 to 1400 CE, then gradually decline into the twentieth century. The largest peak in the vanillic acid in the record occurs from 2000 to 2008 CE. In the para-hydrobenzoic acid record, there are three centennial-scale peaks around 1300, 1550, and 1650 CE superimposed on a long-term decline in the baseline levels throughout the record. Ten-day air mass back trajectories for a decade of fire seasons (March-November, 2006-2015) indicate that Siberia and Europe are the principle modern source regions for wildfire emissions reaching the Lomonosovfonna site. The Lomonosovfonna data are similar to those from the Eurasian Arctic Akademii Nauk ice core during the early part of the record (1220-1400 CE), but the two ice cores diverge markedly after 1400 CE. This coincides with a shift in North Atlantic climate marked by a change of the North Atlantic Oscillation from a positive to a more negative state.
NASA Astrophysics Data System (ADS)
Krumpe, M.; Miyaji, T.; Brunner, H.; Hanami, H.; Ishigaki, T.; Takagi, T.; Markowitz, A. G.; Goto, T.; Malkan, M. A.; Matsuhara, H.; Pearson, C.; Ueda, Y.; Wada, T.
2015-01-01
We present data products from the 300 ks Chandra survey in the AKARI North Ecliptic Pole Deep Field. This field has a unique set of nine-band infrared photometry covering 2-24 μm from the AKARI Infrared Camera, including mid-infrared (MIR) bands not covered by Spitzer. The survey is one of the deepest ever achieved at ˜15 μm, and is by far the widest among those with similar depths in the MIR. This makes this field unique for the MIR-selection of AGN at z ˜ 1. We design a source detection procedure, which performs joint maximum likelihood PSF (point spread function) fits on all of our 15 mosaicked Chandra pointings covering an area of 0.34 deg2. The procedure has been highly optimized and tested by simulations. We provide a point source catalogue with photometry and Bayesian-based 90 per cent confidence upper limits in the 0.5-7, 0.5-2, 2-7, 2-4, and 4-7 keV bands. The catalogue contains 457 X-ray sources and the spurious fraction is estimated to be ˜1.7 per cent. Sensitivity and 90 per cent confidence upper flux limits maps in all bands are provided as well. We search for optical-MIR counterparts in the central 0.25 deg2, where deep Subaru Suprime-Cam multiband images exist. Among the 377 X-ray sources detected there, ˜80 per cent have optical counterparts and ˜60 per cent also have AKARI MIR counterparts. We cross-match our X-ray sources with MIR-selected AGN from Hanami et al. Around 30 per cent of all AGN that have MIR SEDs purely explainable by AGN activity are strong Compton-thick AGN candidates.
Maina, J N
1990-01-01
The general gill morphology of Oreochromis alcalicus grahami, a teleost adapted to high salinity and hyperosmosis, is basically similar to that of other teleostean fish. The species has four pairs of gill arches, all of which have well developed filaments. Each of the arches (holobranchs) has two rows of filaments (hemibranchs). Bilaterally situated secondary lamellae branch from the central axis of the filaments. The lamellae reach their maximum size at the middle of the filament, gradually decrease in size and eventually disappear towards the tip of the filament, which is bare. The leading edge of the gill filament and the immediate interlamellar space is covered by a stratified epithelium consisting of pavement cells, mucous cells, chloride cells and undifferentiated cells. The surface of these cells is made up of concentric microridges. The chloride cells were found only on the primary epithelium (filamental epithelium) and very rarely on the secondary epithelium (lamellar epithelium). Two types of chloride cells were observed in the gills of Oreochromis. The superficial chloride cells have fewer mitochondria concentrated towards the basal aspect of the cell, and a network of tubules towards the apical surface and are less electron dense. These cells intercommunicate with the water through an apical pore. The deep chloride cells have numerous diffuse mitochondria intercalated between a fine profuse tubular network and are more electron dense. These cells are covered by one or more layers of pavement cells and thus do not have access to the external surface. After gradual dilution of the lake water in which the fish were kept, both types of chloride cells remained topographically and ultrastructurally distinct. However, in both kinds of cell the mitochondria decreased in number and size. Initially there was an increase in the diameter and the degree of interdigitation of the tubules followed by a gradual decrease. An increase in the quantity of rough endoplasmic reticulum, particularly at the perinuclear region of the cell, was noted. The morphometric analysis of the branchial system indicated that the gills of Oreochromis are well adapted for gas exchange by having numerous and relatively long gill filaments with a high lamellar density. These features provide a large surface for gas exchange which, when coupled with the notably thin water-blood barrier of an average thickness of only 0.83 micro, would facilitate efficient absorption of oxygen by the gills. Oreochromis alcalicus was observed to be incapable of adapting to freshwater. This may have been due to the progressive degeneration of the chloride cells.(ABSTRACT TRUNCATED AT 400 WORDS)
Federal Register 2010, 2011, 2012, 2013, 2014
2012-08-16
...This action finalizes the review of new source performance standards for the listed oil and natural gas source category. In this action the EPA revised the new source performance standards for volatile organic compounds from leaking components at onshore natural gas processing plants and new source performance standards for sulfur dioxide emissions from natural gas processing plants. The EPA also established standards for certain oil and gas operations not covered by the existing standards. In addition to the operations covered by the existing standards, the newly established standards will regulate volatile organic compound emissions from gas wells, centrifugal compressors, reciprocating compressors, pneumatic controllers and storage vessels. This action also finalizes the residual risk and technology review for the Oil and Natural Gas Production source category and the Natural Gas Transmission and Storage source category. This action includes revisions to the existing leak detection and repair requirements. In addition, the EPA has established in this action emission limits reflecting maximum achievable control technology for certain currently uncontrolled emission sources in these source categories. This action also includes modification and addition of testing and monitoring and related notification, recordkeeping and reporting requirements, as well as other minor technical revisions to the national emission standards for hazardous air pollutants. This action finalizes revisions to the regulatory provisions related to emissions during periods of startup, shutdown and malfunction.
ERIC Educational Resources Information Center
Frazier, Gregory W.
This book provides American Indian and Alaska Native students with sources for securing financial aid for higher education. The first section covers sources of funding and grants for individuals who are pursuing undergraduate degrees. This financial support includes scholarships with state residency requirements, general undergraduate…
ERIC Educational Resources Information Center
Hunt, Thomas C., Ed.; Carper, James C., Ed.
This book presents 24 chapters on religious denomination affiliated institutions of higher education. Most chapters begin with an historical essay followed by annotated bibliographic entries covering primary and secondary sources dating back to 1986 on various denomination-connected institutions. Chapters have the following titles and authors:…
40 CFR 63.7882 - What site remediation sources at my facility does this subpart affect?
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 13 2010-07-01 2010-07-01 false What site remediation sources at my... Remediation What This Subpart Covers § 63.7882 What site remediation sources at my facility does this subpart... remediation as designated by paragraphs (a)(1) through (3) of this section. (1) Process vents. The affected...
Assessing winter cover crop nutrient uptake efficiency using a water quality simulation model
NASA Astrophysics Data System (ADS)
Yeo, I.-Y.; Lee, S.; Sadeghi, A. M.; Beeson, P. C.; Hively, W. D.; McCarty, G. W.; Lang, M. W.
2014-12-01
Winter cover crops are an effective conservation management practice with potential to improve water quality. Throughout the Chesapeake Bay watershed (CBW), which is located in the mid-Atlantic US, winter cover crop use has been emphasized, and federal and state cost-share programs are available to farmers to subsidize the cost of cover crop establishment. The objective of this study was to assess the long-term effect of planting winter cover crops to improve water quality at the watershed scale (~ 50 km2) and to identify critical source areas of high nitrate export. A physically based watershed simulation model, Soil and Water Assessment Tool (SWAT), was calibrated and validated using water quality monitoring data to simulate hydrological processes and agricultural nutrient cycling over the period of 1990-2000. To accurately simulate winter cover crop biomass in relation to growing conditions, a new approach was developed to further calibrate plant growth parameters that control the leaf area development curve using multitemporal satellite-based measurements of species-specific winter cover crop performance. Multiple SWAT scenarios were developed to obtain baseline information on nitrate loading without winter cover crops and to investigate how nitrate loading could change under different winter cover crop planting scenarios, including different species, planting dates, and implementation areas. The simulation results indicate that winter cover crops have a negligible impact on the water budget but significantly reduce nitrate leaching to groundwater and delivery to the waterways. Without winter cover crops, annual nitrate loading from agricultural lands was approximately 14 kg ha-1, but decreased to 4.6-10.1 kg ha-1 with cover crops resulting in a reduction rate of 27-67% at the watershed scale. Rye was the most effective species, with a potential to reduce nitrate leaching by up to 93% with early planting at the field scale. Early planting of cover crops (~ 30 days of additional growing days) was crucial, as it lowered nitrate export by an additional ~ 2 kg ha-1 when compared to late planting scenarios. The effectiveness of cover cropping increased with increasing extent of cover crop implementation. Agricultural fields with well-drained soils and those that were more frequently used to grow corn had a higher potential for nitrate leaching and export to the waterways. This study supports the effective implementation of cover crop programs, in part by helping to target critical pollution source areas for cover crop implementation.
A Model Evaluation Data Set for the Tropical ARM Sites
Jakob, Christian
2008-01-15
This data set has been derived from various ARM and external data sources with the main aim of providing modelers easy access to quality controlled data for model evaluation. The data set contains highly aggregated (in time) data from a number of sources at the tropical ARM sites at Manus and Nauru. It spans the years of 1999 and 2000. The data set contains information on downward surface radiation; surface meteorology, including precipitation; atmospheric water vapor and cloud liquid water content; hydrometeor cover as a function of height; and cloud cover, cloud optical thickness and cloud top pressure information provided by the International Satellite Cloud Climatology Project (ISCCP).
NASA Technical Reports Server (NTRS)
Kimball, John; Kang, Sinkyu
2003-01-01
The original objectives of this proposed 3-year project were to: 1) quantify the respective contributions of land cover and disturbance (i.e., wild fire) to uncertainty associated with regional carbon source/sink estimates produced by a variety of boreal ecosystem models; 2) identify the model processes responsible for differences in simulated carbon source/sink patterns for the boreal forest; 3) validate model outputs using tower and field- based estimates of NEP and NPP; and 4) recommend/prioritize improvements to boreal ecosystem carbon models, which will better constrain regional source/sink estimates for atmospheric C02. These original objectives were subsequently distilled to fit within the constraints of a 1 -year study. This revised study involved a regional model intercomparison over the BOREAS study region involving Biome-BGC, and TEM (A.D. McGuire, UAF) ecosystem models. The major focus of these revised activities involved quantifying the sensitivity of regional model predictions associated with land cover classification uncertainties. We also evaluated the individual and combined effects of historical fire activity, historical atmospheric CO2 concentrations, and climate change on carbon and water flux simulations within the BOREAS study region.
NASA Astrophysics Data System (ADS)
Vaida, Mihai E.; Bernhardt, Thorsten M.
2017-11-01
The femtosecond-laser induced photodissociation of CH3Br adsorbed at sub-monolayer coverage on a solid surface was investigated by time-resolved pump-probe mass spectrometry. To tune the interaction of the CH3Br molecules with the substrate, an Mo(1 0 0) surface was covered with ultrathin insulating MgO layers of variable thickness. By gradually decreasing the magnesia layer thickness to the 2D limit the photodissociation dynamics observed by detection of the methyl fragment indicates an energetic lowering of the relevant methyl bromide excited states due to the increasing spatial proximity of the metallic support. Potential orientational effects of the methyl bromide adsorption geometry are also considered.
Psychosomatic approaches to obstetrics, gynaecology and andrology--a review.
Lal, Mira
2009-01-01
This review aims to clarify the scope and clinical importance of psychosomatic approaches to obstetrics, gynaecology and andrology. This gradually expanding sub-specialty covers a wide domain of complex disease conditions that can be managed more effectively if the various biological, psychological and social aspects are recognised at the start and concurrent treatment initiated. The current need to practise biopsychosocial management of disease conditions is highlighted along with a description of what this would involve. The nine-field psychosomatic approach, which can be applied to everyday clinical encounters, has been illustrated. Clinical applications of the psychosomatic approach are discussed for various conditions including chronic pelvic pain, eating disorders, tokophobia, post-traumatic stress disorder, depression, menstrual disorders, infertility, bereavement and testicular cancer. Cultural considerations and the need for further research are also briefly discussed.
NASA Astrophysics Data System (ADS)
Shang, Yanliang; Han, Tongyin; Shi, Wenjun; Du, Shouji; Qin, Zhichao
2017-10-01
The development of urban subway is becoming more and more rapid and plays an increasingly important role. The shield tunneling method has become the first choice for the construction of urban subway tunnel in the construction of urban subway. The paper takes the interval of Shijiazhuang Metro Line 3 Administrative Center Station and Garden Park Station as the engineering background. The establishment of double shield finite difference model by considering the thickness of covering soil, tunnel excavation and excavation at the same time, distance and other factors, the surface deformation, and soil thickness. The ground deformation law is obtained, the surface settlement is inversely proportional to the overburden thickness and the double line spacing, and the gradual excavation is smaller than the synchronous excavation.
VizieR Online Data Catalog: Classification of 2XMM variable sources (Lo+, 2014)
NASA Astrophysics Data System (ADS)
Lo, K. K.; Farrell, S.; Murphy, T.; Gaensler, B. M.
2017-06-01
The 2XMMi-DR2 catalog (Cat. IX/40) consists of observations made with the XMM-Newton satellite between 2000 and 2008 and covers a sky area of about 420 deg2. The observations were made using the European Photon Imaging Camera (EPIC) that consists of three CCD cameras - pn, MOS1, and MOS2 - and covers the energy range from 0.2 keV to 12 keV. There are 221012 unique sources in 2XMM-DR2, of which 2267 were flagged as variable by the XMM processing pipeline (Watson et al. 2009, J/A+A/493/339). The variability test used by the pipeline is a {Chi}2 test against the null hypothesis that the source flux is constant, with the probability threshold set at 10-5. (1 data file).
Discontinuous model with semi analytical sheath interface for radio frequency plasma
NASA Astrophysics Data System (ADS)
Miyashita, Masaru
2016-09-01
Sumitomo Heavy Industries, Ltd. provide many products utilizing plasma. In this study, we focus on the Radio Frequency (RF) plasma source by interior antenna. The plasma source is expected to be high density and low metal contamination. However, the sputtering the antenna cover by high energy ion from sheath voltage still have been problematic. We have developed the new model which can calculate sheath voltage wave form in the RF plasma source for realistic calculation time. This model is discontinuous that electronic fluid equation in plasma connect to usual passion equation in antenna cover and chamber with semi analytical sheath interface. We estimate the sputtering distribution based on calculated sheath voltage waveform by this model, sputtering yield and ion energy distribution function (IEDF) model. The estimated sputtering distribution reproduce the tendency of experimental results.
Radiological Studies for the LCLS Beam Abort System
DOE Office of Scientific and Technical Information (OSTI.GOV)
Santana Leitner, M.; Vollaire, J.; Mao, X.S.
2008-03-25
The Linac Coherent Light Source (LCLS), a pioneer hard x-ray free electron laser is currently under construction at the Stanford Linear Accelerator Center. It is expected that by 2009 LCLS will deliver laser pulses of unprecedented brightness and short length, which will be used in several forefront research applications. This ambitious project encompasses major design challenges to the radiation protection like the numerous sources and the number of surveyed objects. In order to sort those, the showers from various loss sources have been tracked along a detailed model covering 1/2 mile of LCLS accelerator by means of the Monte Carlomore » intra nuclear cascade codes FLUKA and MARS15. This article covers the FLUKA studies of heat load; prompt and residual dose and environmental impact for the LCLS beam abort system.« less
Carbon Nanotube Bundle Array Cold Cathodes for THz Vacuum Tube Sources
NASA Astrophysics Data System (ADS)
Manohara, Harish M.; Toda, Risaku; Lin, Robert H.; Liao, Anna; Bronikowski, Michael J.; Siegel, Peter H.
2009-12-01
We present high performance cold cathodes composed of arrays of carbon nanotube bundles that routinely produce > 15 A/cm2 at applied fields of 5 to 8 V/µm without any beam focusing. They have exhibited robust operation in poor vacuums of 10-6 to 10-4 Torr- a typically achievable range inside hermetically sealed microcavities. A new double-SOI process was developed to monolithically integrate a gate and additional beam tailoring electrodes. The ability to design the electrodes for specific requirements makes carbon nanotube field emission sources extremely flexible. The lifetime of these cathodes is found to be affected by two effects: a gradual decay of emission due to anode sputtering, and catastrophic failure because of dislodging of CNT bundles at high fields ( > 10 V/µm).
Interpreting intraplate tectonics for seismic hazard: a UK historical perspective
NASA Astrophysics Data System (ADS)
Musson, R. M. W.
2012-04-01
It is notoriously difficult to construct seismic source models for probabilistic seismic hazard assessment in intraplate areas on the basis of geological information, and many practitioners have given up the task in favour of purely seismicity-based models. This risks losing potentially valuable information in regions where the earthquake catalogue is short compared to the seismic cycle. It is interesting to survey how attitudes to this issue have evolved over the past 30 years. This paper takes the UK as an example, and traces the evolution of seismic source models through generations of hazard studies. It is found that in the UK, while the earliest studies did not consider regional tectonics in any way, there has been a gradual evolution towards more tectonically based models. Experience in other countries, of course, may differ.
Li, Ronggang; Liu, Xingyan; Chen, Keming; Ye, Jianjun; Gao, Mingxuan; Ge, Baofeng; Wang, Yong; Xiong, Faming; Liang, Jianping
2010-03-01
Gunshot wound spreads to the surrounding tissues and organs, it is difficult to debride and easy to infect. The conventional treatment is thorough, extensive debridement, fully open drainage, which often causes normal tissue damage and complications. To evaluate the effectiveness of vacuum sealing drainage (VSD) treating the penetrating wound in porcine extremity by MRI and pathological methods so as to provide theoretical basis for future clinical use. Eight healthy adult pigs, weighing (45 +/- 5) kg, were selected. Eight pairs of hind limb penetrating wounds (16 wounds) were made by using Chinese-made 95-type rifle at 25 meters distance, which were randomly divided into experimental group (left side, n=8) and the control group (right side, n=8). After debriding and disinfecting the penetrating wounds at 6 hours after injury, wounds were treated with VSD in experimental group. The ballistics exports of the wounds were covered with single-layer gauze and imports were directly sutured and covered with sterile gauze in control group. The trajectory and the general condition of the adjacent skin were observed. MRI and histological observation were taken at 5, 24, 48, and 72 hours after injury, bacterial counting analysis was done at 0, 12, 24, 48, and 72 hours after injury. The aperture of the trajectory exit and entry were (5.00 +/- 2.50) cm and (0.30 +/- 0.15) cm immediately after injury. The wound surface was clean, rosy without leakage and swelling after 72 hours in experimental group; wound and adjacent tissue were swelling obviously, pus, muscle necrosis and exfoliative tissue was observed, and deep defect cavity at the trajectory exit could be seen in control group. MRI showed that pairs of linear low signal in T1WI and T2WI was seen in trajectory of experimental group at 5 hours after injury, and signal in T1WI gradually increased at disrupted area and tissue deformation area at 24, 48, and 72 hours; in control group, low signal in T1WI was observed at 5 hours after injury, and signal in T2WI gradually increased and a clear boundary between edema and surrounding tissue, and the increase of signal in T1WI was not obvious at 24, 48, and 72 hours. The histological observation showed that wound was dominated by effusion at 5 hours after injury, granulation tissue gradually increased, muscle tissue dissolved and inflammatory cell infiltration was not obvious at 24, 48, and 72 hours in experimental group; in control group, the gradual dissolution of muscle fibers and inflammatory cell infiltration were observed at 5, 24, and 48 hours, muscle tissue became swelling, dissolving and degeneration and a large number of inflammatory cell infiltration gathered into the bacteria group at 72 hours. There was no significant difference in the number of bacteria per gram of tissue (P > 0.05) between experimental group and control group at 0 hour after injury; the numbers of bacteria in control group were significantly higher than those in experimental group at 12, 24, 48, and 72 hours (P < 0.05). MRI combined with pathology show diagnostic meaning in treatment of gunshot wound with VSD. MRI can accurately reflect the scope of limb gunshot wound 72 hours after injury. VSD may be an approach to delay infective time, shorten wound healing time, and promote the growth of healthy granulation tissue.
40 CFR 443.41 - Specialized definitions.
Code of Federal Regulations, 2012 CFR
2012-07-01
... PERFORMANCE AND PRETREATMENT STANDARDS FOR NEW SOURCES FOR THE PAVING AND ROOFING MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Linoleum and Printed Asphalt Felt Subcategory § 443.41 Specialized definitions... from the production of linoleum and printed asphalt felt floor coverings. (c) The term “process...
40 CFR 443.41 - Specialized definitions.
Code of Federal Regulations, 2014 CFR
2014-07-01
... PERFORMANCE AND PRETREATMENT STANDARDS FOR NEW SOURCES FOR THE PAVING AND ROOFING MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Linoleum and Printed Asphalt Felt Subcategory § 443.41 Specialized definitions... from the production of linoleum and printed asphalt felt floor coverings. (c) The term “process...
40 CFR 443.41 - Specialized definitions.
Code of Federal Regulations, 2013 CFR
2013-07-01
... PERFORMANCE AND PRETREATMENT STANDARDS FOR NEW SOURCES FOR THE PAVING AND ROOFING MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Linoleum and Printed Asphalt Felt Subcategory § 443.41 Specialized definitions... from the production of linoleum and printed asphalt felt floor coverings. (c) The term “process...
Lighting the Gym: A Guide to Illuminating Non-Traditional Spaces.
ERIC Educational Resources Information Center
Womack, Jennifer; Nelson, Steve
2000-01-01
Covers all the steps needed to light an open, non-traditional performance space--everything from where to locate lights, support towers, and power sources, to cable and dimmer requirements. Covers safety issues, equipment costs, what students should and should not be allowed to do, and how to deal with electricians and rental companies. (SC)
Biomass and health based forest cover delineation using spectral un-mixing
Mohan Tiruveedhula; Joseph Fan; Ravi R. Sadasivuni; Surya S. Durbha; David L. Evans
2009-01-01
Remote sensing is a well-suited source of information on various forest characteristics such as forest cover type, leaf area, biomass, and health. The use of appropriate layers helps to quantify the variables of interest. For example, normalized difference vegetation index (NDVI) and greenness help explain variability in biomass as well as health of forests....
Relationships between fire frequency and woody canopy cover in a semi-arid African savanna
Andrew T. Hudak; Bruce H. Brockett
2003-01-01
Landscape-scale fire patterns result from complex interactions among weather, ignition sources, vegetation type and the biophysical environment (Hargrove et al. 2000, Morgan et al. 2001, Keane et al. 2002, Hudak, Fairbanks & Brockett in press). Patch characteristics (e.g. woody canopy cover) influence fire characteristics, which in turn influence patch...
ERIC Educational Resources Information Center
Wisconsin State Dept. of Public Instruction, Madison.
This guide is intended to assist Wisconsin school districts in accessing the health care financing system as a means of supporting specialized services. Topics covered include: determination of a local education agency's potential for third-party covered services; the need to become a certified provider dependent upon the funding source;…
Higher Education in the News: A Look into the Topics, Sources, and Views of the Print Media.
ERIC Educational Resources Information Center
Devitt, James
This study examined how higher education is represented in the press by analyzing how four leading newspapers, "The New York Times,""USA Today,""The Washington Post," and "The Wall Street Journal," covered higher education in 1997. The study analyzed a total of 610 higher education stories covering 21…
40 CFR 63.11505 - What parts of my plant does this subpart cover?
Code of Federal Regulations, 2011 CFR
2011-07-01
... subpart cover? 63.11505 Section 63.11505 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Plating and Polishing Operations Applicability and Compliance Dates § 63.11505 What parts of my plant does... section, at all times. A new source is defined in § 63.11511, “What definitions apply to this subpart?” (1...
40 CFR 63.11505 - What parts of my plant does this subpart cover?
Code of Federal Regulations, 2014 CFR
2014-07-01
... subpart cover? 63.11505 Section 63.11505 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Plating and Polishing Operations Applicability and Compliance Dates § 63.11505 What parts of my plant does... paragraphs (a)(1) through (3) of this section, at all times. A new source is defined in § 63.11511, “What...
40 CFR 63.11505 - What parts of my plant does this subpart cover?
Code of Federal Regulations, 2013 CFR
2013-07-01
... subpart cover? 63.11505 Section 63.11505 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Plating and Polishing Operations Applicability and Compliance Dates § 63.11505 What parts of my plant does... paragraphs (a)(1) through (3) of this section, at all times. A new source is defined in § 63.11511, “What...
40 CFR 63.11505 - What parts of my plant does this subpart cover?
Code of Federal Regulations, 2012 CFR
2012-07-01
... subpart cover? 63.11505 Section 63.11505 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Plating and Polishing Operations Applicability and Compliance Dates § 63.11505 What parts of my plant does... paragraphs (a)(1) through (3) of this section, at all times. A new source is defined in § 63.11511, “What...
Measurement of Interfacial Profiles of Wavy Film Flow on Inclined Wall
NASA Astrophysics Data System (ADS)
Rosli, N.; Amagai, K.
2016-02-01
Falling liquid films on inclined wall present in many industrial processes such as in food processing, seawater desalination and electronic devices manufacturing industries. In order to ensure an optimal efficiency of the operation in these industries, a fundamental study on the interfacial flow profiles of the liquid film is of great importance. However, it is generally difficult to experimentally predict the interfacial profiles of liquid film flow on inclined wall due to the instable wavy flow that usually formed on the liquid film surface. In this paper, the liquid film surface velocity was measured by using a non-intrusive technique called as photochromic dye marking method. This technique utilizes the color change of liquid containing the photochromic dye when exposed to the UV light source. The movement of liquid film surface marked by the UV light was analyzed together with the wave passing over the liquid. As a result, the liquid film surface was found to slightly shrink its gradual movement when approached by the wave before gradually move again after the intersection with the wave.
Are international securitized property markets converging or diverging?
NASA Astrophysics Data System (ADS)
Hui, Eddie C. M.; Chen, Jia; Chan, Ka Kwan Kevin
2016-03-01
This study establishes a new framework which combines the recursive model with the Fractionally Integrated Vector Error Correction Model (FIVECM) to investigate the cointegration relationship among 9 securitized real estate indices, which are divided into three groups: Asian, European and North American groups. Our new combined framework has the advantage of reflecting the changes in cointegration dynamics over a period of time instead of a single result for the whole period. The results show that the three groups of markets follow a similar cointegration trend: the cointegration relationship gradually increases before the global financial crisis, reaches a peak during the crisis, and dies down gradually after the crisis. However, cointegration among Asian and European countries occurs at a much later time than cointegration among North American countries does, showing that North America is the source of cointegration, while Asia and Europe are the recipients. This study has important implications to investors and related authorities that investors can adjust their portfolio according to the test results to reduce their risk, while related authorities can take appropriate measures to stabilize the economy and mitigate the effects of financial crises.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tan, Lun C., E-mail: ltan@umd.edu
Since the field-line mixing model of Giacalone et al. suggests that ion dropouts cannot happen in the “gradual” solar energetic particle (SEP) event because of the large size of the particle source region in the event, the observational evidence of ion dropouts in the gradual SEP event should challenge the model. We have searched for the presence of ion dropouts in the gradual SEP event during solar cycle 23. From 10 SEP events the synchronized occurrence of ion and electron dropouts is identified in 12 periods. Our main observational facts, including the mean width of electron–ion dropout periods being consistentmore » with the solar wind correlation scale, during the dropout period the dominance of the slab turbulence component and the enhanced turbulence power parallel to the mean magnetic field, and the ion gyroradius dependence of the edge steepness in dropout periods, are all in support of the solar wind turbulence origin of dropout events. Also, our observation indicates that a wide longitude distribution of SEP events could be due to the increase of slab turbulence fraction with the increased longitude distance from the flare-associated active region.« less
Almli, Lynn M; Alter, Caroline C; Russell, Rebecca B; Tinker, Sarah C; Howards, Penelope P; Cragan, Janet; Petersen, Emily; Carrino, Gerard E; Reefhuis, Jennita
2017-01-27
Birth defects are a leading cause of infant mortality in the United States (1), accounting for approximately 20% of infant deaths. The rate of infant mortality attributable to birth defects (IMBD) in the United States in 2014 was 11.9 per 10,000 live births (1). Rates of IMBD differ by race/ethnicity (2), age group at death (2), and gestational age at birth (3). Insurance type is associated with survival among infants with congenital heart defects (CHD) (4). In 2003, a checkbox indicating principal payment source for delivery was added to the U.S. standard birth certificate (5). To assess IMBD by payment source for delivery, CDC analyzed linked U.S. birth/infant death data for 2011-2013 from states that adopted the 2003 revision of the birth certificate. The results indicated that IMBD rates for preterm (<37 weeks of gestation) and term (≥37 weeks) infants whose deliveries were covered by Medicaid were higher during the neonatal (<28 days) and postneonatal (≥28 days to <1 year) periods compared with infants whose deliveries were covered by private insurance. Similar differences in postneonatal mortality were observed for the three most common categories of birth defects listed as a cause of death: central nervous system (CNS) defects, CHD, and chromosomal abnormalities. Strategies to ensure quality of care and access to care might reduce the difference between deliveries covered by Medicaid and those covered by private insurance.
Land Cover and Hydrologic Variability in Residential Watersheds: Drivers of N Loss in Sacramento CA
NASA Astrophysics Data System (ADS)
McConaghie, J. B.; Zhou, W.; Cadenasso, M. L.
2011-12-01
A key aspect to understanding N loss from urban systems is the link between landscape heterogeneity and variability in non-point source (NPS) nitrogen (N) flux. Because water transports N across the landscape and into receiving streams as runoff, understanding how landscape heterogeneity influences water quantity and movement is also needed. High variability in N loss has been documented from urban systems. However, typical NPS studies characterize landscape heterogeneity by land use and only weakly explain variability in stream N. Focusing on land cover, rather than land use, may better explain observed variability in N loss because land cover elements may better indicate major drivers of N loss. Also, most studies have been conducted in temperate urban systems with stream flow year round. In semi-arid urban systems, storm flow accounts for the majority of stream discharges, and residential irrigation contributes significantly to flows in the dry season. To address how landscape heterogeneity affects variability in water quantity and quality in urban streams, we examined how land cover influences stream flows and N loss in residential streams of metropolitan Sacramento, CA. We analyzed fine-scale variation in land cover and stream N during base flow and storm events in 4 residential watersheds which differ substantially in land cover. We classified land cover using HERCULES (High Ecological Resolution Classification for Urban Landscapes and Environmental Systems) which was developed specifically for urban systems. HERCULES classifies high-resolution aerial photographs into 5 elements: buildings, pavement, herbaceous and woody vegetation, and bare soil. Streams were sampled for discharge, NO3, and Total N using auto samplers during storms in the 2010-2011 rainy season and monthly in the dry season. Partial correlation analysis and multivariate models describe the relationships between land cover elements, water retention, and stream N in these watersheds. We found an early season flush of N from streams during the first storms, and N levels diminished through progressive storms. Also, N concentrations were higher during the rainy season compared to the dry season. High proportion of impervious cover was associated with greater flow rates overall, while high proportion of herbaceous cover was associated with reduced flow rates during storms. The proportion of pavement in the watersheds, a commonly used indicator of urban intensity, did not strongly correlate with increased levels of stream N except during the flush, but did correlate with the magnitude and timing of flows during storms. However, high proportions of building cover, e.g. residential homes, did correlate with higher N fluxes. The use of fertilizers or enhanced N cycling through vegetation management near residential buildings is a possible source of increased N. Management to reduce aquatic enrichment of N from urban ecosystems may be best directed toward identifying N sources and sinks associated with specific land covers. Management must also account for seasonal dynamics, such as annual hydrologic patterns, which drive the loss of N.
Method and apparatus for reducing diffraction-induced damage in high power laser amplifier systems
Campillo, Anthony J.; Newnam, Brian E.; Shapiro, Stanley L.; Terrell, Jr., N. James
1976-01-01
Self-focusing damage caused by diffraction in laser amplifier systems may be minimized by appropriately tailoring the input optical beam profile by passing the beam through an aperture having a uniform high optical transmission within a particular radius r.sub.o and a transmission which drops gradually to a low value at greater radii. Apertures having the desired transmission characteristics may readily be manufactured by exposing high resolution photographic films and plates to a diffuse, disk-shaped light source and mask arrangement.
1979-11-01
shaft seals during the CASREP data period. Five of these CASREPs reported excessive leakage , two reported ruptured inflatable seals , and one reported...failures, like the DDG-37 Class CASREPs, were related to lube oil problems, steam valve problems, or leaking packing ( steam or oil seals ) that had become...sources of this water: (1) gradual deterioration of the turbine labyrinth seals , (2) leaking of exhaust and relief valves, and (3) condensation in the
From ought to is physics and the naturalistic fallacy.
Stanley, Matthew
2014-09-01
In the eighteenth and nineteenth centuries there were many attempts to justify political and social systems on the basis of physics and astronomy. By the early twentieth century such moves increasingly also integrated the life and social sciences. The physical sciences gradually became less appealing as a sole source for sociopolitical thought. The details of this transition help explain the contemporary reluctance to capitalize on an ostensibly rich opportunity for naturalistic social reasoning: the anthropic principle in cosmology, which deals with the apparent "fine-tuning" of the universe for life.
NASA Astrophysics Data System (ADS)
Nezlobin, David; Pariente, Sarah; Lavee, Hanoch; Sachs, Eyal
2017-04-01
Source-sink systems are very common in hydrology; in particular, some land cover types often generate runoff (e.g. embedded rocks, bare soil) , while other obstruct it (e.g. vegetation, cracked soil). Surface runoff coefficients of patchy slopes/plots covered by runoff generating and obstructing covers (e.g., bare soil and vegetation) depend critically on the percentage cover (i.e. sources/sinks abundance) and decrease strongly with observation scale. The classic mathematical percolation theory provides a powerful apparatus for describing the runoff connectivity on patchy hillslopes, but it ignores strong effect of the overland flow directionality. To overcome this and other difficulties, modified percolation theory approaches can be considered, such as straight percolation (for the planar slopes), quasi-straight percolation and models with limited obstruction. These approaches may explain both the observed critical dependence of runoff coefficients on percentage cover and their scale decrease in systems with strong flow directionality (e.g. planar slopes). The contributing area increases sharply when the runoff generating percentage cover approaches the straight percolation threshold. This explains the strong increase of the surface runoff and erosion for relatively low values (normally less than 35%) of the obstructing cover (e.g., vegetation). Combinatorial models of urns with restricted occupancy can be applied for the analytic evaluation of meaningful straight percolation quantities, such as NOGA's (Non-Obstructed Generating Area) expected value and straight percolation probability. It is shown that the nature of the cover-related runoff scale decrease is combinatorial - the probability for the generated runoff to avoid obstruction in unit area decreases with scale for the non-trivial percentage cover values. The magnitude of the scale effect is found to be a skewed non-monotonous function of the percentage cover. It is shown that the cover-related scale effect becomes less prominent if the obstructing capacity decreases, as generally occurs during heavy rainfalls. The plot width have a moderate positive statistical effect on runoff and erosion coefficients, since wider patchy plots have, on average, a greater normalized contributing area and a higher probability to have runoff of a certain length. The effect of plot width depends by itself on the percentage cover, plot length, and compared width scales. The contributing area uncertainty brought about by cover spatial arrangement is examined, including its dependence on the percentage cover and scale. In general, modified percolation theory approaches and combinatorial models of urns with restricted occupancy may link between critical dependence of runoff on percentage cover, cover-related scale effect, and statistical uncertainty of the observed quantities.
Women's Studies: A Bibliographic Essay.
ERIC Educational Resources Information Center
Kirtland, Monika
The essay section provides a definition and short history of women's studies and explores the implications in regard to the administration and teaching of such courses. The bibliography lists and annotates material useful for all levels of education. Information sources covered include government agencies and societies, reference sources (such as…
40 CFR 443.41 - Specialized definitions.
Code of Federal Regulations, 2010 CFR
2010-07-01
... PRETREATMENT STANDARDS FOR NEW SOURCES FOR THE PAVING AND ROOFING MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Linoleum and Printed Asphalt Felt Subcategory § 443.41 Specialized definitions. For the purpose of... linoleum and printed asphalt felt floor coverings. (c) The term “process wastewater pollutants” shall mean...
40 CFR 443.41 - Specialized definitions.
Code of Federal Regulations, 2011 CFR
2011-07-01
... PRETREATMENT STANDARDS FOR NEW SOURCES FOR THE PAVING AND ROOFING MATERIALS (TARS AND ASPHALT) POINT SOURCE CATEGORY Linoleum and Printed Asphalt Felt Subcategory § 443.41 Specialized definitions. For the purpose of... linoleum and printed asphalt felt floor coverings. (c) The term “process wastewater pollutants” shall mean...
A Guide to U.S. Government Documents.
ERIC Educational Resources Information Center
Clark, Suzanne M., Comp.
This listing of government documents in the Bailey/Howe Library of the University of Vermont covers (1) general information sources including guides, current catalogs and indexes, retrospective catalogs and indexes, and biographical and statistical materials; (2) Presidential and Executive Branch activity information sources, such as addresses,…
2014-06-01
User Manual and Source Code for a LAMMPS Implementation of Constant Energy Dissipative Particle Dynamics (DPD-E) by James P. Larentzos...Laboratory Aberdeen Proving Ground, MD 21005-5069 ARL-SR-290 June 2014 User Manual and Source Code for a LAMMPS Implementation of Constant...3. DATES COVERED (From - To) September 2013–February 2014 4. TITLE AND SUBTITLE User Manual and Source Code for a LAMMPS Implementation of
Perforation and bacterial contamination of microscope covers in lumbar spinal decompressive surgery.
Osterhoff, Georg; Spirig, José; Klasen, Jürgen; Kuster, Stefan P; Zinkernagel, Annelies S; Sax, Hugo; Min, Kan
2014-01-01
To determine the integrity of microscope covers and bacterial contamination at the end of lumbar spinal decompressive surgery. A prospective study of 25 consecutive lumbar spinal decompressions with the use of a surgical microscope was performed. For detection of perforations, the microscope covers were filled with water at the end of surgery and the presence of water leakage in 3 zones (objective, ocular and control panel) was examined. For detection of bacterial contamination, swabs were taken from the covers at the same locations before and after surgery. Among the 25 covers, 1 (4%) perforation was observed and no association between perforation and bacterial contamination was seen; 3 (4%) of 75 smears from the 25 covers showed post-operative bacterial contamination, i.e. 2 in the ocular zone and 1 in the optical zone, without a cover perforation. The incidence of microscope cover perforation was very low and was not shown to be associated with bacterial contamination. External sources of bacterial contamination seem to outweigh the problem of contamination due to failure of cover integrity. © 2014 S. Karger AG, Basel.
Perforation and Bacterial Contamination of Microscope Covers in Lumbar Spinal Decompressive Surgery
Osterhoff, Georg; Spirig, José; Klasen, Jürgen; Kuster, Stefan P.; Zinkernagel, Annelies S.; Sax, Hugo; Min, Kan
2014-01-01
Objective To determine the integrity of microscope covers and bacterial contamination at the end of lumbar spinal decompressive surgery. Materials and Methods A prospective study of 25 consecutive lumbar spinal decompressions with the use of a surgical microscope was performed. For detection of perforations, the microscope covers were filled with water at the end of surgery and the presence of water leakage in 3 zones (objective, ocular and control panel) was examined. For detection of bacterial contamination, swabs were taken from the covers at the same locations before and after surgery. Results Among the 25 covers, 1 (4%) perforation was observed and no association between perforation and bacterial contamination was seen; 3 (4%) of 75 smears from the 25 covers showed post-operative bacterial contamination, i.e. 2 in the ocular zone and 1 in the optical zone, without a cover perforation. Conclusions The incidence of microscope cover perforation was very low and was not shown to be associated with bacterial contamination. External sources of bacterial contamination seem to outweigh the problem of contamination due to failure of cover integrity. PMID:24903448
The Astrophysics Source Code Library: An Update
NASA Astrophysics Data System (ADS)
Allen, Alice; Nemiroff, R. J.; Shamir, L.; Teuben, P. J.
2012-01-01
The Astrophysics Source Code Library (ASCL), founded in 1999, takes an active approach to sharing astrophysical source code. ASCL's editor seeks out both new and old peer-reviewed papers that describe methods or experiments that involve the development or use of source code, and adds entries for the found codes to the library. This approach ensures that source codes are added without requiring authors to actively submit them, resulting in a comprehensive listing that covers a significant number of the astrophysics source codes used in peer-reviewed studies. The ASCL moved to a new location in 2010, and has over 300 codes in it and continues to grow. In 2011, the ASCL (http://asterisk.apod.com/viewforum.php?f=35) has on average added 19 new codes per month; we encourage scientists to submit their codes for inclusion. An advisory committee has been established to provide input and guide the development and expansion of its new site, and a marketing plan has been developed and is being executed. All ASCL source codes have been used to generate results published in or submitted to a refereed journal and are freely available either via a download site or from an identified source. This presentation covers the history of the ASCL and examines the current state and benefits of the ASCL, the means of and requirements for including codes, and outlines its future plans.
Wei, Xiao; Wang, Shijie; Ji, Hongbing; Shi, Zhenhua
2018-01-01
The isotope ratios of Sr are useful tracers for studying parent material sources, weathering processes, and biogeochemical cycling. Mineralogical and geochemical investigations of two lateritic weathering covers, in an area close to the Tropic of Cancer (Guangxi Province, southern China), were undertaken to study the regional weathering processes and Sr isotopic sources. We found that weathering and decomposition of Rb- and Sr-bearing minerals change the Sr isotopic composition in weathering products (lateritic soils). Weathering of illite lowered the 87Sr/86Sr ratio whereas dissolving and leaching of carbonate minerals increased the 87Sr/86Sr ratio. An Fe nodular horizon is widely developed on the top of the weathering covers in the studied area and it differs from the lateritic soil horizon in mineral composition, construction, and elemental concentration. Furthermore, both Fe2O3 and P2O5 (concentrations) are negatively correlated with the 87Sr/86Sr ratios, suggesting fixation of apatite by Fe oxides is a controlling factor of the Sr isotopic composition in the Fe nodular horizon. The 87Sr/86Sr and Nb/Sr ratios imply the contents and proportions of Fe nodules and clay are critical in controlling the changes of Sr isotopic composition in the Fe nodular horizon. The two stages of the weathering process of carbonate rocks are revealed by the87Sr/86Sr versus Nb/Sr diagram. The 87Sr/86Sr and Rb/Sr ratios suggest that Sr isotopes in the weathering covers within the studied area are derived mainly from parent rock weathering and that the contributions from allothogenic Sr isotopes are limited. A comparison of Sr isotopic composition signatures in the weathering covers of the studied area and Guizhou Province provided insight into the Sr isotopic source and paleogeographic evolution of southern China. From the Permian to the Triassic, the continental fragment sources of the South China sedimentary basin changed significantly. In the Permian, Southern China presented the paleogeographic pattern that the north was higher (in elevation) than the south. PMID:29373592
Wei, Xiao; Wang, Shijie; Ji, Hongbing; Shi, Zhenhua
2018-01-01
The isotope ratios of Sr are useful tracers for studying parent material sources, weathering processes, and biogeochemical cycling. Mineralogical and geochemical investigations of two lateritic weathering covers, in an area close to the Tropic of Cancer (Guangxi Province, southern China), were undertaken to study the regional weathering processes and Sr isotopic sources. We found that weathering and decomposition of Rb- and Sr-bearing minerals change the Sr isotopic composition in weathering products (lateritic soils). Weathering of illite lowered the 87Sr/86Sr ratio whereas dissolving and leaching of carbonate minerals increased the 87Sr/86Sr ratio. An Fe nodular horizon is widely developed on the top of the weathering covers in the studied area and it differs from the lateritic soil horizon in mineral composition, construction, and elemental concentration. Furthermore, both Fe2O3 and P2O5 (concentrations) are negatively correlated with the 87Sr/86Sr ratios, suggesting fixation of apatite by Fe oxides is a controlling factor of the Sr isotopic composition in the Fe nodular horizon. The 87Sr/86Sr and Nb/Sr ratios imply the contents and proportions of Fe nodules and clay are critical in controlling the changes of Sr isotopic composition in the Fe nodular horizon. The two stages of the weathering process of carbonate rocks are revealed by the87Sr/86Sr versus Nb/Sr diagram. The 87Sr/86Sr and Rb/Sr ratios suggest that Sr isotopes in the weathering covers within the studied area are derived mainly from parent rock weathering and that the contributions from allothogenic Sr isotopes are limited. A comparison of Sr isotopic composition signatures in the weathering covers of the studied area and Guizhou Province provided insight into the Sr isotopic source and paleogeographic evolution of southern China. From the Permian to the Triassic, the continental fragment sources of the South China sedimentary basin changed significantly. In the Permian, Southern China presented the paleogeographic pattern that the north was higher (in elevation) than the south.
Code of Federal Regulations, 2012 CFR
2012-10-01
... Flammability of Flexible Cellular Materials Using a Radiant Heat Energy Source. (v) ASTM E 119-00a, Standard... Method for Surface Flammability of Materials Using a Radiant Heat Energy Source. (vii) ASTM E 648-00, Standard Test Method for Critical Radiant Flux of Floor-Covering Systems Using a Radiant Heat Energy Source...
Code of Federal Regulations, 2013 CFR
2013-10-01
... Flammability of Flexible Cellular Materials Using a Radiant Heat Energy Source. (v) ASTM E 119-00a, Standard... Method for Surface Flammability of Materials Using a Radiant Heat Energy Source. (vii) ASTM E 648-00, Standard Test Method for Critical Radiant Flux of Floor-Covering Systems Using a Radiant Heat Energy Source...
Code of Federal Regulations, 2011 CFR
2011-10-01
... Flammability of Flexible Cellular Materials Using a Radiant Heat Energy Source. (v) ASTM E 119-00a, Standard... Method for Surface Flammability of Materials Using a Radiant Heat Energy Source. (vii) ASTM E 648-00, Standard Test Method for Critical Radiant Flux of Floor-Covering Systems Using a Radiant Heat Energy Source...
Code of Federal Regulations, 2014 CFR
2014-10-01
... Flammability of Flexible Cellular Materials Using a Radiant Heat Energy Source. (v) ASTM E 119-00a, Standard... Method for Surface Flammability of Materials Using a Radiant Heat Energy Source. (vii) ASTM E 648-00, Standard Test Method for Critical Radiant Flux of Floor-Covering Systems Using a Radiant Heat Energy Source...
2016-04-01
DEVELOPING TOPOLOGICAL INSULATOR FIBER BASED PHOTON PAIRS SOURCE FOR ULTRAFAST OPTOELECTRONIC APPLICATIONS NORTHWESTERN UNIVERSITY...REPORT TYPE FINAL TECHNICAL REPORT 3. DATES COVERED (From - To) APRIL 2015 – DEC 2015 4. TITLE AND SUBTITLE DEVELOPING TOPOLOGICAL INSULATOR FIBER BASED...in developing a new source for the production of correlated/entangled photon pairs based on the unique nanolayer properties of topological insulator
Trends in Renewable Energy Consumption and Electricity
2012-01-01
Presents a summary of the nation’s renewable energy consumption in 2010 along with detailed historical data on renewable energy consumption by energy source and end-use sector. Data presented also includes renewable energy consumption for electricity generation and for non-electric use by energy source, and net summer capacity and net generation by energy source and state. The report covers the period from 2006 through 2010.
NASA Astrophysics Data System (ADS)
Minasyants, Gennady; Minasyants, Tamara; Tomozov, Vladimir
2018-03-01
We report the results of the investigation into plasma physical characteristics at various solar activity manifestations and in periods of their absence. These results have been obtained from quantitative estimates of the relative abundance of Fe/O ions in different energy ranges. Maximum values of the Fe/O ratio is shown to correspond to particle fluxes from impulsive flares for ions with energies <2 MeV/n (the most significant manifestation of the FIP effect). In particle fluxes from gradual flares, the Fe/O value decreases smoothly with ion energy and is noticeably inferior to values of fluxes in impulsive events. We have established that the properties of flares of solar cosmic rays indicate their belonging to a separate subclass in the total population of gradual events. Relying on variations in the abundance of Fe/O ions, we propose an explanation of the solar plasma behavior during the development of flares of both classes. Magnetic clouds (a separate type of coronal mass ejections (CME)), which have regions of turbulent compression and are sources of strong geomagnetic storms, exhibit a relative composition of Fe ions comparable to the abundance of Fe in ion fluxes from gradual flares. We have found out that the Fe/O value can be used to detect penetration of energetic flare plasma into the CME body at the initial phase of their joint development and to estimate its relative contribution. During solar minimum with the complete absence of sunspots, the Fe/O ratio during periods of "quiet" solar wind show absolutely low values of Fe/O=0.004-0.010 in the energy range from 2-5 to 30 MeV/n. This is associated with the manifestation of the cosmic ray anomalous component, which causes an increase in the intensity of ion fluxes with a high first ionization potential, including oxygen (O), and elements with a low first ionization potential (Fe) demonstrate the weakening of the fluxes. As for particles with higher energies (Ek>30 MeV/n), the Fe/O increase is due to the decisive influence of galactic cosmic rays on the composition of impurity elements in the solar wind under solar minimum conditions. The relative content of heavy elements in galactic cosmic rays 30-500 MeV/n is similar to values in fluxes from gradual flares during high solar activity. During solar minimum without sunspots, the behavior of Fe/O for different ion energy ranges in plasma flows from coronal holes (CH) and in the solar wind exhibits only minor deviations. At the same time, plasma flows associated with the disturbed frontal CH region can be sources of moderate geomagnetic storms.
Southern Africa seismic structure and source studies
NASA Astrophysics Data System (ADS)
Zhao, Ming
1998-09-01
The upper mantle seismic velocity structure beneath southern Africa is investigated using travel time and waveform data. Waveform and travel time data used in this study come mainly from a large mine tremor in South Africa (msb{b} 5.6) recorded on stations of the southern Africa and the Tanzania Broadband Seismic Experiment. Auxiliary data along similar profiles are obtained from other moderate events within eastern and southern Africa. The waveform data from the large tremor show upper mantle triplications for both the 400 and 670-km discontinuities between 18sp° and 27sp° distance. The most notable feature of the data is a large, late P phase that propagates to at least 27sp°. This phase is striking because of its late arrival time (as much as 15 seconds after direct P at 27sp°) and high amplitude relative to the first arrival. Travel times from all available stations are used to invert for the P wave velocity structure down to 800 km depth and S wave velocity structure down to 200 km using the Wiechert-Herglotz (W-H) inversion technique. The P wave velocities from the uppermost mantle down to 300 km are as much as 3% higher than the global average and are slightly slower than the global average between 300 and 400 km depths. The velocity gradient between 300 and 400 km is 0.0015 1/s. The S wave travel time data yield fast velocities above 200-km depth. The S wave velocity structure appears inconsistent with the P wave structure model indicating varying Poisson's ratio in the upper mantle. Little evidence is found for a pronounced upper mantle low velocity zone. Both sharp and gradual-change 400-km discontinuities are favored by the waveform data. The 670-km discontinuity appears as a gradual-change zone. The source mechanism of the mb 5.6 mining tremor itself is important for seismic discrimination and insight into mining tremor sources. Source parameters for this event as well as some other large mining tremors from the South African gold mines are studied using detailed waveform modeling. All these events (mb > 4.8) indicate normal-faulting slip with P wave nodal planes striking approximately NS. Tectonic stress is essential to control the mining seismicity of large magnitude. Mining geometry also plays an important role in influencing the seismicity. The crustal velocity structure at the study area is investigated in detail using teleseismic receiver function and regional surface wave dispersion data. The results indicate some lateral variation in the shallow crust. The thickness of the crust beneath the GSN station BOSA is 33-36 km. Gradually increasing velocities with depth in the crust are preferred. A thin layer with rather low velocity at the top of the crust beneath BOSA is important for generating the regional waveforms. The crust beneath LBTB is a few kilometers thicker than at BOSA and the Moho there is likely to be dipping. (Abstract shortened by UMI.)
Land cover controls on summer discharge and runoff solution chemistry of semi-arid urban catchments
NASA Astrophysics Data System (ADS)
Gallo, Erika L.; Brooks, Paul D.; Lohse, Kathleen A.; McLain, Jean E. T.
2013-04-01
SummaryRecharge of urban runoff to groundwater as a stormwater management practice has gained importance in semi-arid regions where water resources are scarce and urban centers are growing. Despite this trend, the importance of land cover in controlling semi-arid catchment runoff quantity and quality remains unclear. Here we address the question: How do land cover characteristics control the amount and quality of storm runoff in semi-arid urban catchments? We monitored summertime runoff quantity and quality from five catchments dominated by distinct urban land uses: low, medium, and high density residential, mixed use, and commercial. Increasing urban land cover increased runoff duration and the likelihood that a rainfall event would result in runoff, but did not increase the time to peak discharge of episodic runoff. The effect of urban land cover on hydrologic responses was tightly coupled to the magnitude of rainfall. At distinct rainfall thresholds, roads, percent impervious cover and the stormwater drainage network controlled runoff frequency, runoff depth and runoff ratios. Contrary to initial expectations, runoff quality did not vary in repose to impervious cover or land use. We identified four major mechanisms controlling runoff quality: (1) variable solute sourcing due to land use heterogeneity and above ground catchment connectivity; (2) the spatial extent of pervious and biogeochemically active areas; (3) the efficiency of overland flow and runoff mobilization; and (4) solute flushing and dilution. Our study highlights the importance of the stormwater drainage systems characteristics in controlling urban runoff quantity and quality; and suggests that enhanced wetting and in-stream processes may control solute sourcing and retention. Finally, we suggest that the characteristics of the stormwater drainage system should be integrated into stormwater management approaches.
Pengra, Bruce; Gallant, Alisa L.; Zhu, Zhe; Dahal, Devendra
2016-01-01
The U.S. Geological Survey (USGS) has begun the development of operational, 30-m resolution annual thematic land cover data to meet the needs of a variety of land cover data users. The Continuous Change Detection and Classification (CCDC) algorithm is being evaluated as the likely methodology following early trials. Data for training and testing of CCDC thematic maps have been provided by the USGS Land Cover Trends (LC Trends) project, which offers sample-based, manually classified thematic land cover data at 2755 probabilistically located sample blocks across the conterminous United States. These samples represent a high quality, well distributed source of data to train the Random Forest classifier invoked by CCDC. We evaluated the suitability of LC Trends data to train the classifier by assessing the agreement of annual land cover maps output from CCDC with output from the LC Trends project within 14 Landsat path/row locations across the conterminous United States. We used a small subset of circa 2000 data from the LC Trends project to train the classifier, reserving the remaining Trends data from 2000, and incorporating LC Trends data from 1992, to evaluate measures of agreement across time, space, and thematic classes, and to characterize disagreement. Overall agreement ranged from 75% to 98% across the path/rows, and results were largely consistent across time. Land cover types that were well represented in the training data tended to have higher rates of agreement between LC Trends and CCDC outputs. Characteristics of disagreement are being used to improve the use of LC Trends data as a continued source of training information for operational production of annual land cover maps.