Journal articles: 'Diffuse inputs'

1

Wilson, James G. "Diffuse inputs of nutrients to Dublin Bay." Water Science and Technology 51, no. 3-4 (February 1, 2005): 231–37. http://dx.doi.org/10.2166/wst.2005.0596.

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The River Liffey is the main source of diffuse nutrients to Dublin Bay and accounts for some 85% of all riverine inputs. The total load from the various rivers has been calculated at some 6601 kg N d1 and 748 kg P d1, of which around 82% and 52% are in the form of DIN and phosphate respectively. Sewage discharge adds almost the same again to the load, with minor contributions from the sediments (which may simply be remineralising the particulates) and from nitrogen fixation. However, these inputs are very much less than those exchanged twice-daily by tidal action. These contributions are due to change very shortly with the advent of the new STW in Dublin, but the major change may be more in the speciation of the nutrients, and in particular the dissolved/particulate balance.

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Muhammetoğlu, A., H. Muhammetoğlu, and S. Soyupak. "Evaluation of efficiencies of diffuse allochthonous and autochthonous nutrient input control in restoration of a highly eutrophic lake." Water Science and Technology 45, no. 9 (May 1, 2002): 195–203. http://dx.doi.org/10.2166/wst.2002.0238.

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Mogan Lake is an important recreational area for Metropolitan Ankara-Turkey. It is a shallow eutrophic lake with a dense growth of macrophytes. The main contributors of nutrients and other pollutants to the lake are the creeks carrying the runoff water from the watershed and upland farming land, in addition to the domestic and industrial wastewater discharges from a nearby town and industries. Hydrodynamic and water quality modeling techniques were used to determine the optimum management schemes for the lake restoration and diffuse pollution control. Management scenarios were devised and tested to control allochthonous and autochthonous nutrient inputs to the lake. Phosphorus and nitrogen load reductions were the main test elements for the control of allochthonous nutrient inputs. The scenario analysis revealed that reduction of phosphorus and nitrogen loads from diffused sources will have a marginal effect on controlling eutrophication if macrophyte growth is left uncontrolled. Scenarios employing macrophyte harvesting and sediment dredging have been evaluated for autochthonous nutrient input control. Sediment dredging alone has been shown to yield the most favorable conditions for water quality improvement in Mogan Lake. Further, control of diffuse pollution was an essential final step to achieve an acceptable long-term sustainable water quality improvement in the lake.

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Tetzlaff, B., P. Kreins, R. Kunkel, and F. Wendland. "Area-differentiated modelling of P-fluxes in heterogeneous macroscale river basins." Water Science and Technology 55, no. 3 (February 1, 2007): 123–31. http://dx.doi.org/10.2166/wst.2007.080.

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A model (MEPhos) for the calculation of the total phosphorus output from diffuse sources by drainage, wash-off, groundwater outflow, soil erosion and rainwater sewers as well as from point sources is presented. The model is based on a pathway- and area-differentiated emissions approach and calculates mean long-term P-inputs to surface waters. Phosphotopes are used for spatial discretization and modelling of diffuse P-inputs. Based on the modelling results “hot spots” for high P-loads can be localized and a management option for the input reduction to surface waters can be proposed which are adapted to site properties. The applicability of the model is demonstrated for two macroscale river basins in Germany (∼13,000 km2 each) with contrasting natural conditions and land use patterns.

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Lam, Ying-Wan, and S. Murray Sherman. "Different Topography of the Reticulothalmic Inputs to First- and Higher-Order Somatosensory Thalamic Relays Revealed Using Photostimulation." Journal of Neurophysiology 98, no. 5 (November 2007): 2903–9. http://dx.doi.org/10.1152/jn.00782.2007.

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The thalamic reticular nucleus is a layer of GABAergic neurons that occupy a strategic position between the thalamus and cortex. Here we used laser scanning photostimulation to compare in young mice (9–12 days old) the organization of the reticular inputs to first- and higher-order somatosensory relays, namely, the ventral posterior lateral nucleus and posterior nucleus, respectively. The reticulothalamic input footprints to the ventral posterior lateral nucleus neurons consisted of small, single, topographically organized elliptical regions in a tier away from the reticulothalamic border. In contrast, those to the posterior nucleus were complicated and varied considerably among neurons: although almost all contained a single elliptical region near the reticulothalamic border, in most cases, they consisted of additional discontinuous regions or relatively diffuse regions throughout the thickness of the thalamic reticular nucleus. Our results suggest two sources of reticular inputs to the posterior nucleus neurons: one that is relatively topographic from regions near the reticulothalamic border and one that is relatively diffuse and convergent from most or all of the thickness of the thalamic reticular nucleus. We propose that the more topographic reticular input is the basis of local inhibition seen in posterior nucleus neurons and that the more diffuse and convergent input may represent circuitry through which the ventral posterior lateral and posterior nuclei interact.

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5

Urch, Catherine. "Normal Pain Transmission." Reviews in Pain 1, no. 1 (August 2007): 2–6. http://dx.doi.org/10.1177/204946370700100102.

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• Acute (normal) pain transmission is part of a survival response to prevent tissue damage and attend to and protect damaged tissue. • A cycle of afferent transmission, response to stimuli, followed by temporary hypersensitivity, then attenuation and resolution occurs. • Primary afferent, spinal cord ascending and descending pathways are fixed; however the response elicited is highly dynamic and not a linear relationship with input intensity. • Somatic inputs are topographically accurate, in contrast to diffuse visceral inputs. • Primary afferents code differentially for stimuli (heat, acid, pressure etc) and intensity. • The dorsal horn allows extensive modulation of initial inputs, either excitation or inhibition. • Higher CNS areas allow extensive modulation of inputs, account for the conscious recognition of pain: the intensity, location, emotional and memory aspects. • Descending pathways arising from midbrain regions can be inhibitory or excitatory.

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Bach, M., A. Huber, and H. G. Frede. "Modeling pesticide losses from diffuse sources in Germany." Water Science and Technology 44, no. 7 (October 1, 2001): 189–96. http://dx.doi.org/10.2166/wst.2001.0421.

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A GIS-based model estimates the losses from diffuse sources in surface waters in Germany for 42 active ingredients applied to 11 field crops, vineyards and orchards. For the following pathways of entry: tile drainage, runoff and spray drift, the calculated mean pesticide input amounts to 1490 kg/year, 9060 kg/year and 3350 kg/year, respectively, in 1994. The model results are highly sensitive to the model parameters, primarily the chemical properties of the active ingredients. The modeled water inputs were compared with measured pesticide loads in smaller catchments and large river basins to validate model results. Both datasets agree as to the order of magnitude, nevertheless due to the scale of the study the results should be addressed mainly to comparative interpretations with the focus on the proportions between different active ingredients, soil regions, climates and application periods.

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Bowes, Michael J., Jim T. Smith, Helen P. Jarvie, and Colin Neal. "Modelling of phosphorus inputs to rivers from diffuse and point sources." Science of The Total Environment 395, no. 2-3 (June 2008): 125–38. http://dx.doi.org/10.1016/j.scitotenv.2008.01.054.

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8

Vandenberghe, V., A. van Griensven, W. Bauwens, and P. A. Vanrolleghem. "Propagation of uncertainty in diffuse pollution into water quality predictions: application to the River Dender in Flanders, Belgium." Water Science and Technology 51, no. 3-4 (February 1, 2005): 347–54. http://dx.doi.org/10.2166/wst.2005.0609.

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The uncertainty of water quality predictions caused by uncertainty in the inputs related to emissions of diffuse pollution is analysed. An uncertainty analysis of the effects of diffuse pollution is essential to compare the cost and benefits of measures to lower those emissions. We focus on diffuse nitrate pollution due to fertiliser use. Using an efficient Monte Carlo method and Latin Hypercube sampling, the contribution to the overall uncertainty by each of the inputs is calculated. The modelling environment is ESWAT, an extension of SWAT, which allows for integral modelling of the water quantity and quality processes in river basins. The diffuse pollution sources are assessed by considering crop and soil processes. The crop simulations include growth, uptake of water and nutrients and several land management practices. The in-stream water quality model is based on QUAL2E. The spatial variability of the terrain strongly affects the non-point source pollution processes. The methodology is applied to the Dender basin in Belgium. Eight inputs have significant influence on the time that the nitrate content in the river is higher than 3 mg/l. The uncertainty analysis indicated wide uncertainty bounds (95% percentile bounds differ up to ±50% from the average NO3 predictions).

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Werner, W., and H. P. Wodsak. "The role of non-point nutrient sources in water pollution - present situation, countermeasures, outlook." Water Science and Technology 31, no. 8 (April 1, 1995): 87–97. http://dx.doi.org/10.2166/wst.1995.0270.

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In a recent estimation of the quantitative importance of diffuse and point sources on the nitrogen and phosphorus pollution of surface waters in both parts of Germany just before the reunification, the share of the diffuse sources on the total input was found very similar in the case of N (56 and 57%), but different in the case of P (42% in the old FRG and 33% in the former GDR). The diffuse N and P inputs are dominated by the joint pathways ground water/drain water and soil erosion/surface run off, respectively. The reduction of the diffuse pollution potential until 1995 (compared to 1987/89) is estimated with about 18% for N and 30% for P. This is far below the governmental target of a 50% reduction in the period 1985 to 1995. The reasons, why the up-to-now success of the different countermeasures against diffuse water pollution with N and P from agriculture is still unsatisfactory are discussed. Demands for an accelerated implementation of efficient countermeasures have to be addressed by both farmers and politicians.

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10

Johnson, M. D., and C. J. Heckman. "Interactions between focused synaptic inputs and diffuse neuromodulation in the spinal cord." Annals of the New York Academy of Sciences 1198, no. 1 (June 2010): 35–41. http://dx.doi.org/10.1111/j.1749-6632.2010.05430.x.

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11

Wade, A. J., D. Butterfield, T. Griffiths, and P. G. Whitehead. "Eutrophication control in river-systems: an application of INCA-P to the River Lugg." Hydrology and Earth System Sciences 11, no. 1 (January 17, 2007): 584–600. http://dx.doi.org/10.5194/hess-11-584-2007.

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Abstract. The Integrated Catchments model of Phosphorus dynamics (INCA-P) was applied to the River Lugg to determine the key factors controlling delivery of phosphorus to the main channel and to quantify the relative contribution of diffuse and point sources to the in-stream phosphorus (P) load under varying hydrological conditions. The model is able to simulate the seasonal variations and inter-annual variations in the in-stream total-phosphorus concentrations. However, difficulties in simulating diffuse inputs arise due to equifinality in the model structure and parameters. The River Lugg is split into upper and lower reaches. The upper reaches are dominated by grassland and woodland, so the patterns in the stream-water total-phosphorus concentrations are typical of diffuse source inputs; application of the model leads to estimates of the relative contribution to the in-stream P load from diffuse and point sources as 9:1. In the lower reaches, which are more intensively cultivated and urbanised, the stream-water total-phosphorus concentration dynamics are influenced more by point-sources; the simulated relative diffuse/point contribution to the in-stream P load is 1:1. The model set-up and simulations are used to identify the key source-areas of P in the catchment, the P contribution of the Lugg to the River Wye during years with contrasting precipitation inputs, and the uptake and release of P from within-reach sediment. In addition, model scenarios are run to identify the impacts of likely P reductions at sewage treatment works on the in-stream soluble-reactive P concentrations and the suitability of this as a management option is assessed for reducing eutrophication.

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12

Collins, Adrian L., Steven G. Anthony, Julia Hawley, and Tony Turner. "Predicting potential change in agricultural sediment inputs to rivers across England and Wales by 2015." Marine and Freshwater Research 60, no. 7 (2009): 626. http://dx.doi.org/10.1071/mf08033.

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Recent work has evaluated the gap between current and compliant suspended sediment losses due to farming across England and Wales and the potential for change by 2015. The study adopted the guideline annual average sediment threshold of 25 mg L–1 cited by the European Union Freshwater Fish Directive. Compliance testing required national scale sediment source apportionment to assess the current contributions of diffuse agricultural and urban sector losses, channel bank erosion and point source discharges to the total suspended sediment loads delivered to all rivers. Results suggested that the agricultural sector dominates present day (year 2000) sediment inputs to rivers (1929 kt = 76%) compared with eroding channel banks (394 kt = 15%), diffuse urban sources (147 kt = 6%) and point source discharges (76 kt = 3%). Projected change in farming by 2015, represented by the Business As Usual forecast of structural developments and predicted uptake of sediment mitigation methods, suggested a 9% reduction in sediment losses from the agricultural sector across England and Wales. Further mitigation of diffuse agricultural sediment transfers to watercourses will therefore be necessary to ensure ‘good ecological status’ in some catchments. A similar modelling framework could be applied in other countries.

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13

Novotny, Vladimir. "The next step – incorporating diffuse pollution abatement into watershed management." Water Science and Technology 51, no. 3-4 (February 1, 2005): 1–9. http://dx.doi.org/10.2166/wst.2005.0569.

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The majority of adverse changes in watersheds impairing water quality occurred over a period of thirty to more than one hundred years. In many areas over a period of about 80 years more than 90% of the wetlands were drained, cultivated and converted to agricultural and urban uses. This conversion changed the redox status of the soils and soil cover with a concurrent large increase of suspended solids, dissolved organic matter, nitrogen, and phosphate loads from the watersheds located in the affected regions. The question whether these adverse changes are reversible by reduction or discontinuation of excessive inputs of pollutants came to light and has been analyzed recently after the political changes in Eastern Europe. Reliable dynamic long term models that would describe interactions between nutrient inputs, outputs, storage etc., have not been developed yet. It is becoming apparent that it may take longer for the watersheds to recover after nutrient loads to surface and groundwater are reduced if remedial measures are gradually implemented.

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14

Müller, Claudia E., Nora Spiess, Andreas C. Gerecke, Martin Scheringer, and Konrad Hungerbühler. "Quantifying Diffuse and Point Inputs of Perfluoroalkyl Acids in a Nonindustrial River Catchment." Environmental Science & Technology 45, no. 23 (December 2011): 9901–9. http://dx.doi.org/10.1021/es202140e.

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15

MARSHAK, DAVID W., ELIZABETH S. YAMADA, ANDREA S. BORDT, and WENDY C. PERRYMAN. "Synaptic input to an ON parasol ganglion cell in the macaque retina: A serial section analysis." Visual Neuroscience 19, no. 3 (May 2002): 299–305. http://dx.doi.org/10.1017/s0952523802192078.

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A labeled ON parasol ganglion cell from a macaque retina was analyzed in serial, ultrathin sections. It received 13% of its input from diffuse bipolar cells. These directed a large proportion of their output to amacrine cells but received a relatively small proportion of their amacrine cell input via feedback synapses. In these respects, they were similar to the DB3 bipolar cells that make synapses onto OFF parasol cells. Bipolar cell axons that contacted the ON parasol cell in stratum 4 of the inner plexiform layer always made synapses onto the dendrite, and therefore, the number of bipolar cell synapses onto these ganglion cells could be estimated reliably by light microscopy in the future. Amacrine cells provided the majority of inputs to the ON parasol cell. Only a few of the presynaptic amacrine cell processes received inputs from the same bipolar cells as the parasol cells, and most of the presynaptic amacrine cell processes did not receive any inputs at all within the series. These findings suggest that most of the inhibitory input to the ON parasol cell originates from other areas of the retina. Amacrine cells presynaptic to the parasol ganglion cell interacted very infrequently with other neurons in the circuit, and therefore, they would be expected to act independently, for the most part.

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Jun, K. S., J. W. Kang, and K. S. Lee. "Simultaneous estimation of model parameters and diffuse pollution sources for river water quality modeling." Water Science and Technology 56, no. 1 (July 1, 2007): 155–62. http://dx.doi.org/10.2166/wst.2007.447.

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Diffuse pollution sources along a stream reach are very difficult to both monitor and estimate. In this paper, a systematic method using an optimal estimation algorithm is presented for simultaneous estimation of diffuse pollution and model parameters in a stream water quality model. It was applied with the QUAL2E model to the South Han River in South Korea for optimal estimation of kinetic constants and diffuse loads along the river. Initial calibration results for kinetic constants selected from a sensitivity analysis reveal that diffuse source inputs for nitrogen and phosphorus are essential to satisfy the system mass balance. Diffuse loads for total nitrogen and total phosphorus were estimated by solving the expanded inverse problem. Comparison of kinetic constants estimated simultaneously with diffuse sources to those estimated without diffuse loads, suggests that diffuse sources must be included in the optimization not only for its own estimation but also for adequate estimation of the model parameters. Application of the optimization method to river water quality modeling is discussed in terms of the sensitivity coefficient matrix structure.

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Khatib, Tamer, Azah Mohamed, K. Sopian, and M. Mahmoud. "Solar Energy Prediction for Malaysia Using Artificial Neural Networks." International Journal of Photoenergy 2012 (2012): 1–16. http://dx.doi.org/10.1155/2012/419504.

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This paper presents a solar energy prediction method using artificial neural networks (ANNs). An ANN predicts a clearness index that is used to calculate global and diffuse solar irradiations. The ANN model is based on the feed forward multilayer perception model with four inputs and one output. The inputs are latitude, longitude, day number, and sunshine ratio; the output is the clearness index. Data from 28 weather stations were used in this research, and 23 stations were used to train the network, while 5 stations were used to test the network. In addition, the measured solar irradiations from the sites were used to derive an equation to calculate the diffused solar irradiation, a function of the global solar irradiation and the clearness index. The proposed equation has reduced the mean absolute percentage error (MAPE) in estimating the diffused solar irradiation compared with the conventional equation. Based on the results, the average MAPE, mean bias error and root mean square error for the predicted global solar irradiation are 5.92%, 1.46%, and 7.96%. The MAPE in estimating the diffused solar irradiation is 9.8%. A comparison with previous work was done, and the proposed approach was found to be more efficient and accurate than previous methods.

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Correll, D. L., T. E. Jordan, and D. E. Weller. "Cross Media Inputs to Eastern US Watersheds and Their Significance to Estuarine Water Quality." Water Science and Technology 26, no. 12 (December 1, 1992): 2675–83. http://dx.doi.org/10.2166/wst.1992.0368.

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Extensive research on Chesapeake Bay estuary, its drainage basin, and its airshed have now demonstrated that atmospheric deposition and diffuse land discharges are the largest sources for many parameters affecting estuarine water quality. For example, phosphorus and sediments are transported to the Bay largely in overland storm flows, nitrate largely in atmospheric deposition and in ground water, many pesticides and other toxic materials in surface waters and atmospheric deposition, and silicate primarily in ground water. Concerns over point sources such as sewage treatment outfalls and industrial outfalls have led to greatly improved treatment methods, alleviating the relative magnitude of these sources. The realization of the magnitude and importance of diffuse sources has led to research on improved land use practices, including better patterns of land use in the Chesapeake Bay landscape. One example is the use of and improved management of forested riparian buffer zones in the coastal plain part of the drainage basin.

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Balogh, S., M. Meyer, and K. Johnson. "Diffuse and point source mercury inputs to the Mississippi, Minnesota, and St. Croix Rivers." Science of The Total Environment 213, no. 1-3 (June 1998): 109–13. http://dx.doi.org/10.1016/s0048-9697(98)00081-3.

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20

Legović, Tarzan, Nedžad Limić, and Vladivoj Valković. "Estimation of diffuse inputs to a coastal sea: Solution to an inverse modelling problem." Estuarine, Coastal and Shelf Science 30, no. 6 (June 1990): 619–34. http://dx.doi.org/10.1016/0272-7714(90)90097-b.

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21

Matsui, Y., K. Narita, T. Inoue, and T. Matsushita. "Using precise data sets on farming and pesticide properties to verify a diffuse pollution hydrological model for predicting pesticide concentration." Water Science and Technology 56, no. 1 (July 1, 2007): 71–80. http://dx.doi.org/10.2166/wst.2007.437.

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Verification of a diffuse pollution model involves comparing results actually observed with those predicted by precise model inputs. Acquisition of precise model inputs is, however, problematic. In particular, when the target catchment is large and substantial estimation uncertainty exists, not only model verification but also prediction is difficult. Therefore, in this study, rice-farming data were collected for all paddy fields from all farmers in a catchment and pesticide adsorption and degradation rates in paddy field soil samples were measured to obtain precise model inputs. The model inputs successfully verified the model's capability to predict pesticide concentrations in river water. Sensitivity analyses of the model inputs elucidated the processes significantly affecting pesticide runoff from rice farms. Pesticide adsorption and degradation rates of the soil did not significantly affect pesticide concentrations, although pesticide discharge to river water accounted for less than 50% of the total quantity of pesticide applied to fields, possibly owing to pesticide adsorption and degradation. The timing of increases in pesticide concentrations in river water was affected mostly by the farming schedule, including the time of pesticide application and irrigation, and secondarily by rainfall events.

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22

Bach, M., A. Huber, and H. G. Frede. "Input pathways and river load of pesticides in Germany - a national scale modeling assessment." Water Science and Technology 43, no. 5 (March 1, 2001): 261–68. http://dx.doi.org/10.2166/wst.2001.0301.

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A model has been developed which estimates the magnitude and the spatial distribution of pesticide losses from diffuse sources (surface run-off, tile drains and spraydrift) into surface waters for the entire area of Germany. The cumulative annual losses of 42 active ingredients applied to 11 field crops, orchards and vineyards are calculated for river basins in Germany based on grid maps with a resolution of 1 × 1 km2. The model validation showed a sufficient degree of accuracy of the model results compared to measured pesticide loads in 13 small catchments. According to the model results the pesticide input from diffuse sources into surface waters amounted to 13.8 t in 1994 aggregated for the entire area of Germany. Input via surface runoff contributed 9.1 t while tile drainage was 1.4 t and spraydrift 3.4 t respectively. Alongside the model calculations empirical data of the pesticide load of rivers in Germany are presented. A comparison of the measured river loads with the modeled inputs from non-point sources leads to the conclusion that in most regions of Germany the largest portion of the load is due to the input from farm effluents.

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Tetzlaff, B., and F. Wendland. "P-pollution in a heavily urbanized river basin from point and diffuse sources: the River Ruhr case study (Germany)." Water Science and Technology 56, no. 1 (July 1, 2007): 29–37. http://dx.doi.org/10.2166/wst.2007.433.

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An area-differentiated model approach (MEPhos) for the quantification of mean annual P-inputs from point and diffuse sources is presented. The following pathways are considered: artificial drainage, wash-off, groundwater outflow, soil erosion, rainwater sewers, combined sewer overflows, municipal waste water treatment plants and industrial effluents. Based on the modelling results “hot spots” for high P-loads can be localized and management option for the input reduction to surface waters proposed. The model is applied to the River Ruhr basin (4,485 km2) in Germany with contrasting natural conditions, land use patterns as well as population and industry densities.

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Vink, Rona, Horst Behrendt, and Wim Salomons. "Development of the heavy metal pollution trends in several European rivers: an analysis of point and diffuse sources." Water Science and Technology 39, no. 12 (June 1, 1999): 215–23. http://dx.doi.org/10.2166/wst.1999.0549.

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A comparison has been made between the metal pollution in several European rivers in various stages of clean-up and management for the period of 1980-1996. The investigated rivers were Rhine, Meuse, Scheldt, Weser and Elbe. The results from this comparison showed that the simple statement that characterizes the river Elbe as ‘the most polluted river in Europe’ is a simplification. Three independent methods are presented to estimate point and diffuse source contributions in emissions and riverine transports. All methods were applied to the Elbe and Rhine rivers to estimate the contribution of point and diffuse sources for six heavy metals. The results of the source apportionment estimates show that there are temporal differences in source strength and source origin. A dramatic drop in industrial inputs and inputs from waste water treatment plants can be observed. The comparison of all methods shows some differences, which might be caused by retention processes (such as sedimentation) in the river system.

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Puthussery, Theresa, Jacqueline Gayet-Primo, W. Rowland Taylor, and Silke Haverkamp. "Immunohistochemical identification and synaptic inputs to the diffuse bipolar cell type DB1 in macaque retina." Journal of Comparative Neurology 519, no. 18 (October 17, 2011): 3640–56. http://dx.doi.org/10.1002/cne.22756.

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Puthussery, Theresa, Jacqueline Gayet-Primo, W. Rowland Taylor, and Silke Haverkamp. "Immunohistochemical identification and synaptic inputs to the diffuse bipolar cell type DB1 in macaque retina." Journal of Comparative Neurology 519, no. 18 (October 17, 2011): Spc1. http://dx.doi.org/10.1002/cne.22794.

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Bastian, J. "Plasticity in an electrosensory system. I. General features of a dynamic sensory filter." Journal of Neurophysiology 76, no. 4 (October 1, 1996): 2483–96. http://dx.doi.org/10.1152/jn.1996.76.4.2483.

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1. In this study we describe changes in neuronal responses within the primary electrosensory processing nucleus of a weakly electric fish that occur when the fish are exposed to repetitive patterns of electrosensory stimuli. Extracellular single-unit recordings show that pyramidal cells within the electrosensory lateral line lobe develop, over a time course of several minutes, an insensitivity to repetitive stimuli applied to a cell's receptive field (local stimulus). The pyramidal cell response cancellation only develops if the local stimulus is applied simultaneously with a diffuse pattern of electrosensory stimulation that affects the entire fish, or with proprioceptive stimuli. 2. The mechanism by which responses to repetitive afferent inputs are canceled relies on the central generation of "negative image inputs" that provide increased inhibitory input to a cell's apical dendrites at times when excitatory afferent input is increased. The negative image input becomes excitatory when afferent excitation is reduced or when input from inhibitory interneurons is predominant. The integration of a specific pattern of receptor afferent input with the complementary negative image input results in strong attenuation of pyramidal cell responses. The negative image inputs are plastic, so that a single pyramidal cell can learn to reject a variety of afferent input patterns. 3. These electric fish commonly experience repetitive electrosensory signals as a result of changes in posture. Because the electric organ is located in the trunk and tail, cyclical movements associated with exploratory behaviors result in amplitude modulations (AMs) of the electric field, and these AMs alter electroreceptor afferent firing frequency but not the firing frequency of second-order pyramidal cells. The adaptive cancellation mechanism described in this study can account for the insensitivity of pyramidal cells to reafferent electrosensory stimulation caused by tail movements and other postural changes. 4. The tail movements generate proprioceptive as well as electrosensory inputs, and either of these signals alone provides sufficient information for the generation of negative image inputs. The size of the negative image is larger, however, if both inputs are active. 5. The synaptic plasticity underlying the development of negative image inputs has a long-term component; under appropriate conditions changes in synaptic efficacy persist for > 30 min. 6. Normally functioning glutamatergic synapses are necessary for the expression of the synaptic plasticity associated with this cancellation mechanism. The development of negative image responses is blocked by micropressure ejection of the glutamate antagonist 6,7-dinitroquinoxaline-2,3-dione into the neighborhood of the pyramidal cell apical dendrites. 7. The adaptive cancellation of repetitive inputs is based on anti-Hebbian mechanisms; that is, correlated pre- and postsynaptic activity lead to a reduction in the excitatory input provided by the plastic synapses. As has been shown for several other systems, the cancellation mechanism reduces the cells responses to reafferent patterns of sensory input. In addition, the results of this study indicate that the mechanism may be more general, enabling the system to also cancel patterns of input resulting from exogenous stimuli.

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Zhao, Juan, Jian Min Bian, and Zhen Zhen Zhang. "Spatial and Temporal Changes of Nitrogen Balance and its Environmental Impact of Eastern Liao River29." Advanced Materials Research 864-867 (December 2013): 22–25. http://dx.doi.org/10.4028/www.scientific.net/amr.864-867.22.

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The nitrogen (N) balance is studied the spatial and temporal changes of N inputs and outputs in eastern Liao River watershed. Using the social economic and the related hydrological data from 2001 to 2010, the N inputs are quantified from the aspects of fertilizer use, human and animal excreta, atmospheric deposition and biological nitrogen fixation, and the N outputs from the aspects of denitrification, ammonium volatilization, crop harvest. Results indicates that the mean annual N inputs vary from 185.01 ×106kga-1 to 200.68×106kga-1, with a mean value of 192.02×106 kga-1. Diffuse sources shows that chemical N fertilizer constitutes the largest source of total N inputs, accounting for about 50.23%. The mean annual N outputs range from 132.10×106kga-1 to 170.38×106kga-1, and agricultural N output is the maximum output. The large gap between N inputs and outputs results in the high N surplus of 132.10×106 kga-1~170.38×106kga-1, which results in the transfer of N from the terrestrial system to the aquatic system and increasing the risk of water eutrophication.

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Röpke, B., M. Bach, and H. G. Frede. "DRIPS - a decision support system estimating the quantity of diffuse pesticide pollution in German river basins." Water Science and Technology 49, no. 3 (February 1, 2004): 149–56. http://dx.doi.org/10.2166/wst.2004.0184.

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The GIS based decision support system DRIPS - Drainage Spraydrift and Runoff Input of Pesticides in Surface Waters - has been developed to estimate the predicted environmental concentration (PECsw) of pesticides in surface waters resulting from diffuse sources. PECsw can be calculated on a catchment scale by quantifying the expected mean daily inputs of pesticides via surface runoff, tile drainage and spraydrift for various types of river basins characterized by their daily discharges. DRIPS is fitted with a Graphical User Interface (GUI) to provide easy access to the model algorithms. Model parameters like dose rate, DT50, Koc and date of pesticides application, etc. can be modified by the user in order to generate customized scenarios predicting PECsw for a choice of field crops, orchards and vineyards. Results are available as grid cell maps for the territory of Germany with high temporal and spatial resolution featuring distinct PECsw values for approximately 400 catchments.

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Miller, B. S. "Mussels as biomonitors of point and diffuse sources of trace metals in the clyde sea area, Scotland." Water Science and Technology 39, no. 12 (June 1, 1999): 233–40. http://dx.doi.org/10.2166/wst.1999.0551.

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Following a series of international conferences on pollution of the North Sea, the UK Government committed itself in 1990 to reducing the inputs of certain dangerous substances reaching the aqueous environment from point and diffuse sources. The target was a 50% reduction in loadings over the period 1985-95. Metals loadings from rivers and sewage works to the Clyde Sea Area are presented for the period 1990-97. These are compared to trace metals body burdens in mussels collected from shores throughout the Clyde Sea Area over the period 1980-97. For most metals, no clear trend either increasing or decreasing was observed in metals loadings from point sources or in mussel body burdens. The exceptions were cadmium, which showed downward trends with time in loadings and in concentrations in Clyde Estuary mussels, and lead, which showed a downward trend in mussel concentrations. Metals loadings from point sources may have reached baseline levels, below which further reductions will be difficult to achieve. Elevated mussel body burdens of specific metals provided good evidence that some shores are severely affected by point source inputs, others by bulk contamination from far-field point sources, and others by diffuse sources of metals.

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Prasuhn, Volker, and Ulrich Sieber. "Changes in diffuse phosphorus and nitrogen inputs into surface waters in the Rhine watershed in Switzerland." Aquatic Sciences 67, no. 3 (September 2005): 363–71. http://dx.doi.org/10.1007/bf02506139.

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Prasuhn, Volker, and Ulrich Sieber. "Changes in diffuse phosphorus and nitrogen inputs into surface waters in the Rhine watershed in Switzerland." Aquatic Sciences 67, no. 3 (August 29, 2005): 363–71. http://dx.doi.org/10.1007/s00027-005-0774-5.

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Mohaupt, V., U. Sieber, J. van den Roovaart, C. G. Verstappen, F. Langenfeld, and M. Braun. "Diffuse sources of heavy metals in the Rhine basin." Water Science and Technology 44, no. 7 (October 1, 2001): 41–49. http://dx.doi.org/10.2166/wst.2001.0385.

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An estimate of diffuse sources of heavy metals (Hg, Cd, Cu, Zn, Pb, Cr, Ni) in the Rhine catchment stressed the urban storm water discharges in the German part and drainage flow in the Dutch part as the most important pathways. Additional sources are erosion and, to a far lesser extent, atmospheric deposition on open water areas. All other pathways were of minor importance. Meanwhile, after reduction of the point sources by between 72-95%, the diffuse sources dominate the total emissions. For several metals the anthropogenic diffuse sources amounted to 40-80%, the point sources to 15-40% and the geogeneous sources to 5-40%. The estimated inputs sufficiently agreed with the loads of the river Rhine. For the estimation, mean values were used for the water masses and the substance concentrations of the different hydrological pathways. It is recommended to undertake further studies on diffuse sources of heavy metals in urban areas and on the possibilities to improve urban storm water management. The calculation methods and the recommendations of the International Commission for the Protection of the Rhine (ICPR) are explained in detail.

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Wendland, F., R. Kunkel, H. Bogena, H. Gömann, and P. Kreins. "Water fluxes and diffuse nitrate pollution at river basin scale: coupling of agro-economic models and hydrological approaches." Water Science and Technology 55, no. 3 (February 1, 2007): 133–42. http://dx.doi.org/10.2166/wst.2007.081.

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An integrated model system has been developed to estimate the impact of nitrogen reduction measures on the nitrogen load in groundwater and in river catchment areas. The focus lies on an area-wide, regionally differentiated, consistent link-up between the indicator “nitrogen balance surplus” and nitrogen charges into surface waters. As a starting point of the analysis actual nitrogen surpluses in the soil were quantified using the agro-economic RAUMIS-model, which considers the most important N-inputs to the soil and N-removals from the soil through crop harvest. The most important pathways for diffuse nitrogen inputs into river systems are modelled with the water balance model GROWA. Additionally, the time-dependent nitrogen degradation along the nitrogen pathways in soil and groundwater are modelled using the WEKU-model. The two selected river basins in Germany cover a variety of landscape units with different hydrological, hydrogeological and socio-economic characteristics. The results indicate a wide range of annual nitrogen surpluses for the rural areas between than 10 kg N ha−1•a−1 and 200 kg N ha−1•a−1 or more, depending on the type and intensity of farming. The level of nitrogen inputs into the surface waters is reduced because of degradation processes during transport in soil and groundwater. Policy impact analyses for a nitrogen tax and a limitation of the livestock density stress the importance of regionally adjusted measures.

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Matsui, Y., K. Narita, T. Inoue, and T. Matsushita. "Screening level analysis for monitoring pesticide in river water using a hydrological diffuse pollution model with limited input data." Water Science and Technology 53, no. 10 (May 1, 2006): 173–81. http://dx.doi.org/10.2166/wst.2006.310.

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To predict rice-farming pesticide concentrations in river water with imprecise model inputs for screening-level analysis, a basin-scale runoff model was developed. The Monte Carlo method was applied to create estimates of input data regarding agricultural work schedules and parameters for pesticide decomposition and sorption in solids and water. The prediction accuracy of the model was evaluated when used with non-optimised pesticide parameters; the model was calibrated using hydrological data alone without reference to observed pesticide concentration data. Overall, predictions for the pesticide concentrations were successful within order-of-magnitude accuracy. The pesticide rankings according to the predicted concentration roughly agreed with those observed. The success of screening-level analysis indicates that the model prediction can help in selection of pesticides to be monitored and in determining the monitoring schedule for the river basin.

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36

Cohen, Martin. "The Diffuse Near- and Mid-Infrared Emission from the Galaxy." Symposium - International Astronomical Union 204 (2001): 35–46. http://dx.doi.org/10.1017/s0074180900225862.

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Recognition of an isotropic cosmic near-infrared (NIR) and mid-infrared (MIR) background involves the removal of the zodiacal foreground (both scattered and reradiated), of the truly diffuse Galactic foreground (dominated by fluorescent bands of polcyclic aromatic hydrocarbons), and of resolved and unresolved Galactic point sources. I discuss model simulations of the near- and mid-infrared point source sky from which one can assess its particular contribution to the diffuse Galactic infrared foreground. I will also indicate the transitional stage which characterizes our knowledge of fundamental stellar parameters that are essential inputs to any such models. Using the latest version of the SKY model (Wainscoat et al. 1992; Cohen 1993; Cohen 1994; Cohen et al. 1994; Cohen 1995; Ruphy et al. 1997), I will demonstrate matches to deep point source counts for a variety of passbands and galactic latitudes, and will try to quantify the uncertainties achievable in model predictions of the integrated surface brightness due to the smearing of all these foreground point sources.

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Panagos, Panos, Cristiano Ballabio, Emanuele Lugato, Arwyn Jones, Pasquale Borrelli, Simone Scarpa, Alberto Orgiazzi, and Luca Montanarella. "Potential Sources of Anthropogenic Copper Inputs to European Agricultural Soils." Sustainability 10, no. 7 (July 9, 2018): 2380. http://dx.doi.org/10.3390/su10072380.

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In the European Union (EU), copper concentration in agricultural soil stems from anthropogenic activities and natural sources (soil and geology). This manuscript reports a statistical comparison of copper concentrations at different levels of administrative units, with a focus on agricultural areas. Anthropogenic sources of diffuse copper contamination include fungicidal treatments, liquid manure (mainly from pigs), sewage sludge, atmospheric deposition, mining activities, local industrial contamination and particles from car brakes. Sales of fungicides in the EU are around 158,000 tonnes annually, a large proportion of which are copper based and used extensively in vineyards and orchards. Around 10 million tonnes of sewage sludge is treated annually in the EU, and 40% of this (which has a high copper content) is used as fertilizer in agriculture. In the EU, 150 million pigs consume more than 6.2 million tonnes of copper through additives in their feed, and most of their liquid manure ends up in agricultural soil. These three sources (sales of fungicides, sewage sludge and copper consumption for pigs feed) depend much on local traditional farming practices. Recent research towards replacing copper spraying in vineyards and policy developments on applying sewage and controlling the feed given to pigs are expected to reduce copper accumulation in agricultural soil.

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Behrendt, H. "A comparison of different methods of source apportionment of nutrients to river basins." Water Science and Technology 39, no. 12 (June 1, 1999): 179–87. http://dx.doi.org/10.2166/wst.1999.0545.

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Seven different methods of source apportionment were applied in an analysis of the nutrient emissions from point and diffuse sources of 14 river basins in Northeastern Germany. The aim was to compare the results relating to the uncertainties of the methods and to test whether the difference between the emissions and load is caused by systematical errors or by retention and loss processes in the river systems. Beside the simplest method, where the diffuse emission is the difference between the observed transport and the point source inventory, other immission methods including a nutrient retention term are applied. The emission methods used also estimate the diffuse nutrient inputs by different ways. For all methods the relative standard deviation of the estimated diffuse emission was calculated for each of the river basins. The mean standard deviation of the original data sets for all emission methods and the immission approaches with the retention term was 22% for nitrogen and 48% for phosphorus. By variation of additionally introduced coefficients this standard deviation can be reduced to 18% and 24% for nitrogen and phosphorus, respectively. Tests regarding possible systematical under- and/or overestimation of the measured load and the diffuse emissions, respectively, show indications of such a behavior for phosphorus, only. Nevertheless, a large difference between the nutrient emissions and the load remains, which can only be explained by intensive retention processes.

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Dąbrowska, Jolanta, Paweł Dąbek, and Iwona Lejcuś. "Identifying Surface Runoff Pathways for Cost-Effective Mitigation of Pollutant Inputs to Drinking Water Reservoir." Water 10, no. 10 (September 21, 2018): 1300. http://dx.doi.org/10.3390/w10101300.

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Surface runoff (overland flow) is the main element of the water cycle and is also crucial in the delivery of phosphorus and nitrogen from catchments to water bodies. Watercourses and reservoirs in agricultural catchments are particularly vulnerable to the delivery of biogenic compounds via surface runoff. Forested riparian buffers are considered effective in reducing nutrients and sediment loads in runoff from agricultural areas. Regrettably, the concentration of surface runoff may significantly limit the buffering capacity of vegetation strips, as channelised overland flow tends to avoid buffers without making optimal use of their ability to retain nutrients and sediment. The aim of the undertaken research was to delineate surface runoff pathways from surrounding areas to a drinking water reservoir as well as to identify potential concentration spots of overland flow. The research was conducted for the Dobromierz drinking water reservoir (GPS N: 50°54′27″, E: 16°14′37″). The reservoir is situated in a submountain catchment, where rainfall is an important factor taking part in driving diffuse P and N loads from land to water. Presented GIS-based method using high resolution Digital Terrain Model obtained from Light Detection and Ranging (LiDAR) allowed to determine areas with a tendency for high accumulation (concentration) of overland flow in the direct catchment of the reservoir. As main surface runoff areas, three sites each exceeding 100 ha were designated. The analysis of spatial data also allowed to establish the risk of agricultural diffuse pollution transfer via channelised overland flow to the reservoir from individual accumulation areas. It was found that in the forested part of the catchment (serving as a riparian buffer) there is no visible tendency for concentration of surface runoff, but simultaneously the vegetation strip does not prevent the transfer of runoff waters from agricultural areas through the privileged pathways of concentrated flow.

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Jones, Edward G. "Thalamic circuitry and thalamocortical synchrony." Philosophical Transactions of the Royal Society of London. Series B: Biological Sciences 357, no. 1428 (December 29, 2002): 1659–73. http://dx.doi.org/10.1098/rstb.2002.1168.

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The corticothalamic system has an important role in synchronizing the activities of thalamic and cortical neurons. Numerically, its synapses dominate the inputs to relay cells and to the γ–amino butyric acid (GABA)ergic cells of the reticular nucleus (RTN). The capacity of relay neurons to operate in different voltage–dependent functional modes determines that the inputs from the cortex have the capacity directly to excite the relay cells, or indirectly to inhibit them via the RTN, serving to synchronize high– or low–frequency oscillatory activity respectively in the thalamocorticothalamic network. Differences in the α–amino–3–hydroxy–5–methyl–4–isoxazolepropionic acid (AMPA) subunit composition of receptors at synapses formed by branches of the same corticothalamic axon in the RTN and dorsal thalamus are an important element in the capacity of the cortex to synchronize low–frequency oscillations in the network. Interactions of focused corticothalamic axons arising from layer VI cortical cells and diffuse corticothalamic axons arising from layer V cortical cells, with the specifically projecting core relay cells and diffusely projecting matrix cells of the dorsal thalamus, form a substrate for synchronization of widespread populations of cortical and thalamic cells during high–frequency oscillations that underlie discrete conscious events.

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Patoine, M., S. Hébert, and F. D'Auteuil-Potvin. "Water quality trends in the last decade for ten watersheds dominated by diffuse pollution in Québec (Canada)." Water Science and Technology 65, no. 6 (March 1, 2012): 1095–101. http://dx.doi.org/10.2166/wst.2012.850.

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The aim of this work is to evaluate and discuss river water quality trends over the last decade in ten watersheds where diffuse pollution represents more than half of the annual load of phosphorus (P) and nitrogen (N). Trend analyses taking into account flow data indicate a significant reduction of total P in eight rivers, of ammonia N in five rivers, of nitrate + nitrite in four rivers, of total filtered N in three rivers and of suspended solids in two rivers. An increase of turbidity was observed in four rivers and, for fecal coliforms, no trends. P decrease can be explained by reduced mineral P inputs on cropped lands related to means such as agro-environmental fertilization plans and addition of phytase in pig and poultry feed. However, for seven of them, median P concentrations remain at least two times greater than the Québec water quality guideline for protection of rivers against eutrophication. Concentrations of other parameters remain problematic in some rivers too. These results indicate the need to continue the efforts for further diffuse pollution reduction. Future work should better quantify actions taken at the watershed scale to reduce diffuse pollution.

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Crabtree, Bob, Sarah Kelly, Hannah Green, Graham Squibbs, and Gordon Mitchell. "Water Framework Directive catchment planning: a case study apportioning loads and assessing environmental benefits of programme of measures." Water Science and Technology 59, no. 3 (February 1, 2009): 407–16. http://dx.doi.org/10.2166/wst.2009.875.

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Complying with proposed Water Framework Directive (WFD) water quality standards for ‘good ecological status’ in England and Wales potentially requires a range of Programmes of Measures (PoMs) to control point and diffuse sources of pollution. There is an urgent need to define the benefits and costs of a range of potential PoMs. Water quality modelling can be used to understand where the greatest impact in a catchment can be achieved through ‘end of pipe’ and diffuse source reductions. This information can be used to guide cost-effective investment by private water companies and those with responsibilities for agricultural, industrial and urban diffuse inputs. In the UK, river water quality modelling with the Environment Agency SIMCAT model is regarded as the best current approach to support decision making for river water quality management and planning. The paper describes how a SIMCAT model has been used to conduct a trial WFD integrated catchment planning study for the River Ribble catchment in the North West of England. The model has been used to assess over 80 catchment planning scenarios. The results are being used support a national assessment of the cost-effectiveness of proposed PoMs.

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Delia-Gabriela, Calinoiu, and Paulescu Marius. "Impact of Aerosol on the Estimation Accuracy of Solar Radiation." Annals of West University of Timisoara - Physics 60, no. 1 (August 1, 2018): 97–103. http://dx.doi.org/10.2478/awutp-2018-0010.

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AbstractThe paper is focused on the solar irradiance estimation in clear-sky conditions and an aerosol-loaded atmosphere. Two parametric models developed by our group and three empirical models are tested. The estimates of the parametric models are based on three atmospheric parameters (ozone, nitrogen dioxide and water vapor column content) and the aerosol properties quantified by means of several specific parameters (Ångström turbidity coefficient, single scattering albedo, asymmetry factor). The empirical models contain no inputs for aerosol properties. Data collected from 10 stations were used to test the models. The inputs for the parametric models were retrieved from Aerosol Robotic Network - AERONET. Global and diffuse solar irradiance data at high-quality standards were retrieved from the Baseline Surface Radiation Network BSRN. A comparative analysis of the models’ accuracy in estimating clear-sky solar irradiance is discussed from the perspective of aerosol proprieties.

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Bowes, Michael J., Jim T. Smith, Helen P. Jarvie, Colin Neal, and Ruth Barden. "Changes in point and diffuse source phosphorus inputs to the River Frome (Dorset, UK) from 1966 to 2006." Science of The Total Environment 407, no. 6 (March 2009): 1954–66. http://dx.doi.org/10.1016/j.scitotenv.2008.11.026.

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Terekhanova, T. A., B. Helm, J. Traenckner, and P. Krebs. "IWRM decision support with material flow analysis: consideration of urban system input." Water Science and Technology 66, no. 11 (December 1, 2012): 2432–38. http://dx.doi.org/10.2166/wst.2012.470.

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A review of material flow analysis (MFA) tools, comparison of case studies and analysis of approximately 20 MFA tools (static, semi-empirical models) are performed. The evaluation of the quantification procedures revealed several deficits in the approaches. The following principal complications for a reliable quantification of inputs from the urban water system are identified: (1) frequently insufficient data for urban system model validation (e.g. combined sewer overflow (CSO) discharges); (2) the necessity for additionally quantifying diffuse sources in order to verify modelling results at basin scale, where both input pathways occur, and (3) the contradictions arising when describing the highly dynamic urban system with the help of static MFA models. However, a wise selection of appropriate calculation procedures with regard to the concrete systems characteristics and available data can minimize the model deviations significantly. Criteria and suggestions for designing adapted quantification procedures are given.

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EKESTEN, BJORN, and PETER GOURAS. "Cone and rod inputs to murine retinal ganglion cells: Evidence of cone opsin specific channels." Visual Neuroscience 22, no. 6 (November 2005): 893–903. http://dx.doi.org/10.1017/s0952523805226172.

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To identify ultraviolet (UV) and middle- (M) wavelength-sensitive cone and rod signals in murine retinal ganglion cells, single ganglion cell responses were studied in anesthetized, light-adapted C57/BL6 mice with tungsten microelectrodes driven through the sclera and vitreous to the neural retina. One hundred fifty-four ganglion cells were examined in 43 retinas of 34 mice. The retina was stimulated with diffuse flashes and/or pulses of ultraviolet (360 nm) or green (520 nm) light in the presence and absence of a strong steady orange adapting light. Twelve ganglion cells were studied in the dark-adapted retina in order to identify the signals of rods. Three functionally different types of ganglion cells were found: (1) phasic responding cells (31%) with no spontaneous activity and large impulse amplitudes; (2) tonic responding cells (60%) with irregular, low frequency (5–10 Hz) spontaneous activity and smaller impulse amplitudes; and (3) metronome-like cells (9%) with regular, relatively high-frequency (20–40 Hz) spontaneous activity. A few cells (1%) had habituating responses. Every cell encountered was affected by diffuse stimulation. The more common two types were excited at either the ON or OFF or at both the ON and OFF phases of stimulation. Type III cells had weaker responses, sometimes only inhibited by turning off a light. In the light-adapted state, most cells received signals of the same polarity from UV- and M-cones but UV-cone inputs were usually more dominant, especially in ventral retina. A fraction of cells received signals from only UV- (18%) or only M- (3%) cones. In rare cases (2%) these cone inputs had an opposite polarity on the same cell. In the dark-adapted state, all cells were at least four or five logarithmic units more sensitive and more to green than ultraviolet light. The results indicate that co-expression of both UV-and M-cone opsins cannot be ubiquitous in murine retina. Some cones, especially UV cones, exist without the presence of any functional M-cone opsin. This must be the case to explain the presence of ganglion cells that receive inputs only from UV-cones and others that receive inputs of opposite polarity from UV- and M-cones. The results support the hypothesis that murine retina has the physiological capacity to relay signals to the brain that allow the sensing of chromatic contrast and color vision.

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Hiscock, Keith. "The ecology and conservation of sublittoral hard substratum ecosystems in Scotland." Proceedings of the Royal Society of Edinburgh. Section B. Biological Sciences 100 (1992): 95–112. http://dx.doi.org/10.1017/s0269727000011088.

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SynopsisThe species assemblages which occur on sublittoral hard substrata in Scotland reflect the following major environmental features: physiographic nature of the coastline, salinity, wave exposure, strength of tidal streams and depth modified by factors such as geographical location, geology, local topographical features, artificial substrata, scour, grazing, disturbance and pollution. Sublittoral hard substratum habitats and communities are affected by many of mans' activities including fishing and harvesting, damage by fishing equipment, organic input, nutrient input, chemical inputs, harbours and moorings, and construction work. Energy generation through wave and tidal power are potential threats. Some of mans' activities also create habitats of scientific interest. Conservation of sublittoral hard substratum habitats and communities requires: description of the character and distribution of habitats, communities and species; evaluation of survey information through application of nature conservation criteria; identification of areas/sites of nature conservation importance; establishment of appropriate consultative and statutory frameworks; obtaining information on biology of species, dynamics/longevity of natural communities and species, and mechanisms ‘driving’ communities; evaluation of damage and recovery; evaluation of effects of diffuse pollution; informing, consulting and educating.

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Holdefer, R. N., J. C. Houk, and L. E. Miller. "Movement-Related Discharge in the Cerebellar Nuclei Persists After Local Injections of GABAA Antagonists." Journal of Neurophysiology 93, no. 1 (January 2005): 35–43. http://dx.doi.org/10.1152/jn.00603.2004.

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Limb movement-related neurons in the cerebellar nuclei (CN) typically produce bursts of discharge in association with movement. Consequently, given the inhibitory nature of the Purkinje cell (PC) projection to CN, it is puzzling that only a minority of movement-related PCs pause; the majority burst. Some of the movement-related CN activity may be the result of excitation from collaterals of mossy and climbing fiber projections to the cerebellar cortex. The only other input to CN is diffuse and neuromodulatory, from locus ceruleus and raphe nuclei. To investigate the role of the excitatory mossy fiber input, single units in CN were recorded in macaque monkeys during the performance of reaching and manipulation tasks, before and after blocking the PC input with local microinjections of GABAA antagonists (bicuculline or SR95531). After these injections, the movement-related modulation of CN discharge was greater and began earlier, compared with the modulation in the preinjection group of neurons. These observations indicate that an important excitatory drive is provided by extracerebellar inputs to CN, most likely from collaterals of mossy fibers. PCs may serve primarily to regulate this activity, by either pausing or bursting as necessary.

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Kunkel, R., H. Bogena, H. Goemann, P. Kreins, and F. Wendland. "Management of regional German river catchments (REGFLUD) impact of nitrogen reduction measures on the nitrogen load in the River Ems and the River Rhine." Water Science and Technology 51, no. 3-4 (February 1, 2005): 291–99. http://dx.doi.org/10.2166/wst.2005.0603.

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The REGFLUD-project, commissioned by Germany's Federal Research Ministry (BMBF), addresses the problem of reducing diffuse pollution from agricultural production. The objective of the project is the development and application of multi-criteria scientific methods, which are able to predict diffuse pollution in river basins subject to economic feasibility and social acceptability. The selected river basins (Ems and Rhine basins) cover a variety of landscape units with different hydrological, hydrogeological and socio-economic characteristics. This paper focuses on the analysis of the effects of certain policy measures to reduce diffuse pollution by nitrogen. For this purpose a model system consisting of an agricultural sector model, a water balance model and a residence time/denitrification model was developed and applied. First results indicate a wide range of annual nitrogen surpluses for the rural areas between less than 10 kg N/ha up to 200 kg N/ha or more depending on the type and intensity of farming. Compared to the level of nitrogen surpluses the level of nitrogen inputs into the surface waters is relatively moderate because of degradation processes during transport in soil and groundwater. Policy impact analysis for a nitrogen tax and a limitation of the livestock density stress the importance of regionally tailored measures.

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Hollitt, C., and M. Johnston-Hollitt. "Feature Detection in Radio Astronomy using the Circle Hough Transform." Publications of the Astronomical Society of Australia 29, no. 3 (2012): 309–17. http://dx.doi.org/10.1071/as11051.

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AbstractWhile automatic detection of point sources in astronomical images has experienced a great degree of success, less effort has been directed towards the detection of extended and low-surface-brightness features. At present, existing telescopes still rely on human expertise to reduce the raw data to usable images and then to analyse the images for non-pointlike objects. However, the next generation of radio telescopes will generate unprecedented volumes of data making manual data reduction and object extraction infeasible. Without developing new methods of automatic detection for extended and diffuse objects such as supernova remnants, bent-tailed galaxies, radio relics and halos, a wealth of scientifically important results will not be uncovered. In this paper we explore the response of the Circle Hough Transform to a representative sample of different extended circular or arc-like astronomical objects. We also examine the response of the Circle Hough Transform to input images containing noise alone and inputs including point sources.

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Journal articles on the topic 'Diffuse inputs'

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