1,950 results on '"Rao, P. S. C."'
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152. Gastrointestinal Motility in Patients with Ulcerative Colitis
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Rao, S. S. C. and Read, N. W.
- Abstract
In the first study 62 patients with ulcerative colitis and 20 healthy controls were fed a test meal of mashed potatoes and baked beans containing transit markers. Mouth-to-caecum transit was significantly slower in the patients than in controls; gastric emptying, however, was similar. Patients with active colitis had proximal colonic stasis, with rapid transit through the rectosigmoid region. In the patients with quiescent colitis the colonic distribution of markers was normal. Stool weight and frequency were significantly higher in the patients with active colitis. In the second study anorectal function was assessed in 29 patients with ulcerative colitis and in 12 healthy controls by measuring interluminal pressures at multiple sites in the anus and rectum before and during serial distention of a rectal balloon. Overall, resting and maximum squeeze sphincter pressures did not differ in patients with active or quiescent colitis and controls; however, in six patients with moderately severe colitis and incontinence, maximum squeeze pressure was significantly lower than in controls. The rectal volumes required to induce sensations of wind, a desire to defaecate, and pain were significantly lower in the patients with active colitis than patients with quiescent colitis and controls. Rectal pressures in response to rectal distention were higher in patients with active colitis. During disease remission rectal sensitivity decreased and rectal compliance increased. In the third study integrated pressure activity of the sigmoid colon, rectum, and anus was studied in patients with ulcerative colitis and healthy controls before and during provocation by rectal infusion of 1500 ml of warm saline. Resting motor activity was significantly lower in the patients with active colitis than in patients with quiescent colitis and controls. No anorectal contractions during the 1-h study were recorded in 7 of 18 patients with active colitis, 1 of 17 with quiescent colitis, and 1 of 18 controls. The volume of saline infused before leakage and total volume retained were significantly lower in the patients than in controls. The amplitude of regular contractions after rectal infusion of saline Was significantly higher in patients with active colitis than in patients with quiescent colitis and controls. Thus, the rectum in active colitis is tense and quiescent but responds to stimulation by generating large contractions.
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- 1990
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153. Sorption and Transport of Hydrophobic Organic Chemicals in Aqueous and Mixed Solvent Systems: Model Development and Preliminary Evaluation
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Rao, P. S. C., Hornsby, A. G., Kilcrease, D. P., and Nkedi‐Kizza, P.
- Abstract
A theoretical approach, based upon the assumption of predominance of solvophobic interactions, was formulated to quantitatively describe the sorption and transport of hydrophohic organic chemicals (HOC) from aqueous and aqueous‐organic‐solvent mixtures. In the theoretical approach, solvent‐sorbate interactions (solubility) are specifically considered in order to predict sorbate‐sorbent interactions (sorption). For HOC sorption from a single solvent, the HOC sorption coefficient was shown to increase loglinearly with the hydrocarbonaceous surface area (HSA) of the sorbate. For HOC sorption from aqueous‐organic binary solvent mixtures, the sorption coefficient is predicted to decrease exponentially as the fraction of organic cosolvent increases. This is a direct consequence of increased HOC solubility in the binary solvent. Because sorption and mobility of HOC are inversely related, a decrease in sorption coefficient leads to an enhanced HOC mobility as the fraction of organic cosolvent is increased. A preliminary verification of the theory was performed by an analysis of published data for (i) HOC sorption by soils and sediments from water, (ii) HOC retention by reversed‐phase chromatographic sorbents during isocratic elution with methanol‐water binary solvent mixture, and (iii) HOC mobility on soil‐TLC plates eluted with ethanol‐water mixtures.
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- 1985
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154. Field Study of Solute Movement in a Highly Aggregated Oxisol with Intermittent Flooding: II. Picloram
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Rao, P. S. C., Green, R. E., Balasubramanian, V., and Kanehiro, Y.
- Abstract
Most of the applied herbicide picloram (potassium salt of 4‐amino‐3,5,6‐trichloropicolinic acid) was retained in the top 40‐cm depth of the Molokai soil with cumulative applications of 48 to 74 cm water following application of the chemical to the soil surface. Distribution of picloram in the soil profile one week after each irrigation was determined by in situsampling of soil solution with porous ceramic cups placed at several depths. Although movement of the picloram peak was retarded more than was anticipated from equilibrium adsorption measurements, a significant fraction of the applied herbicide moved ahead of the peak deep into the profile (down to the 143‐cm depth) after a single application of 24‐cm water. Rapid flow through macropore sequences combined with temporary retention of picloram in aggregate micropores appear to be responsible for the unusual pattern of movement. Published data for nitrate movement in the same field plots of Molokai soil were compared with picloram movement data to provide a measure of the relative mobility of these solutes. A comparison of the results reported here with published field data of solute leaching in other soils indicated a greater retardation of solute peak movement in Molokai soil than in less aggregated soils.
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- 1974
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155. Experimental and Mathematical Description of Nonadsorbed Solute Transfer by Diffusion in Spherical Aggregates
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Rao, P. S. C., Jessup, R. E., Rolston, D. E., Davidson, J. M., and Kilcrease, D. P.
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Diffusion of nonadsorbed solutes (3H2O and 36Cl‐) out of two sizes of porous ceramic spheres (0.55‐ and 0.75‐cm radius) was measured. These data were analyzed to provide independent estimates of the input parameters required in two simulation models for describing solute transport in aggregated porous media with distinct mobile and stagnant pore‐water regions. Tracer‐saturated porous spheres were placed in tracer‐free 0.01NCaCl2solution and the rate of tracer diffusion out of the porous spheres was measured by monitoring the increase in tracer concentration with time in the external electrolyte solution. Experimental results were analyzed using two mathematical models. Fick's second law, written in spherical coordinates, formed the basis for Model I. In Model II, the time‐rate of solute transfer into or out of the porous spheres was assumed to be proportional to the difference in tracer concentration inside and outside the porous spheres. The analytical solution to Model I for given initial and boundary conditions was substituted into Model II, to derive an explicit expression relating the empirical mass transfer rate coefficient (α) in Model II and known physical constants of the system. This theoretical analysis indicated that the α value is dependent upon the sphere radius, time of diffusion, volumetric water contents inside and outside the sphere, and the molecular diffusion coefficient. Over a range of experimental conditions, excellent agreement was found between measured α values and those calculated using the analytic expression developed here.
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- 1980
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156. Solute Transport in Aggregated Porous Media: Theoretical and Experimental Evaluation
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Rao, P. S. C., Rolston, D. E., Jessup, R. E., and Davidson, J. M.
- Abstract
Breakthrough curves (BTC's) for 36Cl‐and 3H2O displacement through water‐saturated columns of aggregated and nonaggregated porous media were measured at pore‐water velocities varying over an order of magnitude (2 to 96 cm/hour). These BTC's were used to verify two conceptual solute transport models in which the pore‐water was partitioned into inter‐ and intra‐aggregate regions. In both models, convective‐dispersive solute transport was assumed to be limited to the inter‐aggregate pore‐water region, while the intra‐aggregate pore‐water was assumed to behave as a diffusion sink/source for solute. The rate of solute transfer between the two pore‐water regions was described either by Fick's second law of diffusion written in spherical coordinates (Model I) or was assumed proportional to the concentraion difference between the two regions (Model II). Values of all input parameters in each model were measured in independent experiments rather than by curvefitting to the measured BTC's. Agreement between calculated and measured BTC's at all velocities was good for both models. The value of the mass transfer rate coefficient in Model II was found to vary with aggregate radius, time, and pore‐water velocity. This result was predicted based on theory and experimental results presented in an earlier paper. Conditions under which solute diffusion in aggregates leads to tailing or asymmetry in measured BTC's (during saturated water flow) were identified from a sensitivity analysis using Model I. For certain aggregate radii and pore‐water velocities, the diffusion sink/source effects of the aggregates could be incorporated into the dispersion coefficient, and this lumped‐parameter approach was used to successfully describe the measured BTC's.
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- 1980
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157. Factors Influencing Oxygen Consumption Rates in Flooded Soils
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Reddy, K. R., Rao, P. S. C., and Patrick, W. H.
- Abstract
Thirty‐seven surface soil samples varying in physico‐chemical properties were incubated under reduced (anaerobic) conditions to study the factors influencing oxygen consumption rates. Oxygen consumption rates were measured after introduction of a known amount of oxygen into a reduced (anaerobic) soil system and following the disappearance of oxygen as a function of time. The time dependence of oxygen consumption in all flooded soils could be described as a two‐phase first order reaction process. Rapid oxygen consumption during Phase I was followed by relatively slower consumption during Phase II. The first‐order rate coefficient (k1, hour−1) for Phase I was approximately the same for all 37 soils evaluated, whereas each soil was characterized by a different rate coefficient (k11, hour−1) for Phase II. The average value for k1was 0.15 hour−1(coefficient of variation = 20%) while the values of k11ranged from 0.0027 to 0.054 hour−1. Step‐wise regression analysis of the data showed that NaOAc‐extractable Fe of a reduced soil was the single best predictor of k11and also the fractional consumption associated with Phase I. Significant improvement in these regressions was obtained when total NH4‐N content of the reduced soil, in addition to reducible Fe2+was considered.
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- 1980
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158. Evaluation of Conceptual Models for Describing Nonequilibrium Adsorption‐Desorption of Pesticides During Steady‐flow in Soils
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Rao, P. S. C., Davidson, J. M., Jessup, R. E., and Selim, H. M.
- Abstract
Breakthrough curves (BTC) from miscible displacement of two pesticides through three soils were measured for two input concentrations of each pesticide. These BTC data were used to evaluate two conceptual models for describing the nonequilibrium adsorption‐desorption of pesticides in soils under steady‐state water flow conditions. In both models, adsorption on one group of sites was assumed to be instantaneous, while the rate of adsorption on the second group of sites followed either nonlinear reversible kinetics (Model I) or was a diffusion‐controlled process (Model II). Parameters in both models were estimated by curve‐fitting model predictions to one set of measured BTC data using a nonlinear least‐squares optimization procedure. These parameter values were then used to verify the conceptual models by comparing simulated and measured BTC for a different input concentration. A different set of model parameters were required to describe the BTC data for each input concentration for the same soil‐pesticide combination. The measured 3H2O BTC for all three soils were symmetrical in shape with no apparent tailing. Evaluation of Model I and II using these BTC suggested that the mobile‐immobile water concept may not be applicable to the three soils used in this study.
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- 1979
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159. Evaluation of a Capillary Bundle Model for Describing Solute Dispersion in Aggregated Soils
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Rao, P. S. C., Green, R. E., Ahuja, L. R., and Davidson, J. M.
- Abstract
A simple capillary bundle model was evaluated for describing solute dispersion in two well‐aggregated soils of Hawaii. The model enables the use of pore‐water velocity distribution rather than an average pore‐water velocity. The pore‐size distribution was calculated from the soil water characteristic data. The position and relative shape of the break‐through curves calculated by the capillary bundle model was dependent more on the pore‐water velocity distribution than on dispersion owing to mixing within a pore. The predicted breakthrough curves were extremely skewed and did not describe the measured curves. The mixing of solute between adjacent flow paths, a process not accounted for in the model, apparently resulted in failure of the model. A measure of pore accessibility and interconnectedness of pore sequences is essential for quantitative description of the influence of soil pore geometry on solute dispersion.
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- 1976
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160. A Stereoselective and Regioselective Total Synthesis of (π)-Trichodiene
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Welch, S. C., Rao, A. S. C. P., and Gibbs, C. G.
- Abstract
Trichodiene (1), a sesquiterpene hydrocarbon, was isolated and characterized by Nozoe and Machida in 1970.1 Trichodiene (1) has been shown to be the biogenetic precursor of the trichothecane family of sesquiterpenoids characterized by the cytotoxic fungal metabolite (-)-trichodermin (2).2,3 We recently reported a total synthesis of (±)-trichodiene (1) via lactone 3.4 Now, we wish to report another stereoselective total synthesis of (±)-trichodiene (1) via lactone 3 which is highly regioselective.
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- 1976
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161. Field Study of Solute Movement in a Highly Aggregated Oxisol with Intermittent Flooding: I. Nitrate
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Balasubramanian, V., Kanehiro, Y., Rao, P. S. C., and Green, R. E.
- Abstract
Movement of applied nitrate (a concentrated solution sprayed uniformly over the soil surface) under intermittent flooding was investigated in Molokai silty clay (Typic Torrox), an important soil for sugarcane (Saccharum officinarumL.) and pineapple (Ananas comosus) production in Hawaii. Nitrate distribution in the profile was characterized under an extended irrigation scheme by in situsampling of soil solutions with suction probes 1 week after each water application. The nitrate peak moved only one‐third as far as would have been predicted by a piston displacement model. Equilibration of applied nitrate solution with the aggregated surface soil for 1 week prior to flood irrigation further retarded nitrate leaching. Apparently, equilibration involved bulk flow and diffusion of nitrate into aggregate micropores where the solute was less susceptible to transport in water being conducted mostly in the macropores during and soon after irrigation. Prediction of nitrate distribution based on dispersion (diffusion plus convection) equation approximated experimental results for successive irrigations reasonably well when equation parameters were obtained by fitting one set of experimental data. The drawback of this theoretical model is discussed.
- Published
- 1973
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162. Using index and physically-based models to evaluate the intrinsic groundwater vulnerability to non-point source pollutants in an agricultural area in Sardinia (Italy).
- Author
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Porru, Maria Chiara, Hassan, Shawkat B. M., Abdelmaqsoud, Mostafa S. M., Vacca, Andrea, Da Pelo, Stefania, and Coppola, Antonio
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AGRICULTURE ,GROUNDWATER pollution ,WATER table ,GROUNDWATER ,GROUNDWATER analysis ,SOIL profiles ,HYDROGEOLOGY - Abstract
This research aims at studying the intrinsic vulnerability of groundwater to diffuse environmental pollutants in the Muravera coastal agricultural area of Sardinia, Italy. The area faces contamination risks arising from agricultural practices, especially the use of fertilizers, pesticides, and various chemicals that can seep into the groundwater. The study examined the interplay among hydrological elements, including soil characteristics, groundwater depth, climate conditions, land use, and aquifer properties. To do that, the outcomes of FLOWS 1D physically-based agrohydrological model were analyzed in parallel with those of the overlay-and-index model SINTACS, in a sort of reciprocal benchmarking. By using FLOWS, water movement and solute transport in the unsaturated zone were simulated by, respectively, solving the Richard Equation (RE) and the Advection-Dispersion equation (ADE). As such, this model allowed to account for the role of soil hydraulic and hydrodispersive properties variability in determining the travel times of a conservative solute through the soil profile to the groundwater. For FLOWS simulations, a complete dataset was used as input, including soil horizons, soil physical and hydraulic properties of 36 soil profiles, average annual depth to groundwater table at each soil profile (ranging from 1 to 50 meters), and climatic temporal series data on rainfall and evapotranspiration. Detailed analyses of travel times for the movement of 25, 50, 75, and 100% of the solute mass to reach groundwater were conducted, revealing that the depth to groundwater predominantly influences vulnerability. This result was coherent with SINTACS vulnerability map due to the large impact of the depth to groundwater on SINTACS analysis. [ABSTRACT FROM AUTHOR]
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- 2024
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163. Identification of metacommunities in bioregions with historical habitat networks.
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Harisena, Nivedita Varma, Grêt‐Regamey, Adrienne, and Van Strien, Maarten J.
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HABITAT conservation ,BIODIVERSITY conservation ,KNOWLEDGE transfer ,TIME series analysis ,HABITATS - Abstract
Although metacommunity theory provides many useful insights for conservation planning, the transfer of this knowledge to practice is hampered due to the difficulty of identifying metacommunities in bioregions. This study aims to identify the spatial extent of metacommunities at bioregional scales using current and historical habitat data, especially because contemporary biodiversity patterns may be a result of time‐lagged responses to historical habitat configurations. Further, this estimation of the metacommunity spatial extent is based on both the habitat structure and the dispersal ability of the species. Focusing on dragonfly and damselfly (odonate) species in the eastern Swiss Plateau, the research uses wetland habitat information spanning over 110 years to create a time series of nine habitat networks between 1899 and 2010. From these networks, we identified the spatial extents of metacommunities based on the year of habitat information as well as on watershed boundaries. To identify the best metacommunity spatial extents, the study investigates whether patch pairs within a metacommunity exhibit greater similarity in species composition (i.e. lower beta‐diversity) than patch pairs between metacommunities. For the different metacommunities, we further investigated correlations between gamma diversity and metacommunity size and compare them to theoretical expectations. In both analyses we found that augmenting spatial metacommunity identification with historical geographical proximity results in stronger associations with biodiversity patterns (beta and gamma diversity) than when using only current‐day habitat or watershed information. [ABSTRACT FROM AUTHOR]
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- 2024
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164. On the Development of State-of-the-Art Computational Decision Support Systems for Efficient Water Quality Management: Prospects and Opportunities in a Climate Changing World.
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Fameso, Festus Oluwadare, Ndambuki, Julius Musyoka, Kupolati, Williams Kehinde, and Snyman, Jacques
- Abstract
The concept of water quality has often generally revolved around the all-round safety of water for human consumption. The quality of much of the 3% of the earth's humanly consumable water classed as freshwater is under threat of climate change, rising population numbers, indiscriminate land usage, detrimental agricultural practices and contamination from poor waste management. The need for optimal water quality enhancement has become more germane to sustainable socio-economic development. This paper examines the evolution of efforts made by the scientific community over the years to ensure water quality can be characterized and properly managed to ensure the global ever-growing demand for clean water for human consumption is continually met. The development of state-of-the-art computational decision support systems (DSS) should play a vital role. However, efforts in this regard are currently bedevilled by major challenges such as quantifying, measuring, processing and controlling the numerous metrics of water quality, as well as their adaptation and integration into a fully developed universal water quality model. In addressing these challenges, a shift towards simpler modelling approaches and the integration of uni-purpose models which can be cascaded into decision-making systems is being popularly proposed. However, with technological advancements already stimulating a water quality management revolution, there is a shift in paradigm to more universal modelling attempts with great optimism towards overcoming the challenges of developing universal water quality models and DSS. The prospects and opportunities of a water quality management renaissance offered by radical scientific innovations look promising, as the world races with time to provide support systems that can help deal better with the dynamics of sustainable water supply in increasingly contaminable environments and progressively unpredictable climates. [ABSTRACT FROM AUTHOR]
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- 2024
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165. Determination of a pedotransfer function for specific air–water interfacial area in sandy soils: A pore network‐informed multigene genetic programming approach.
- Author
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Mirghafari, Rasoul, Nikooee, Ehsan, Raoof, Amir, and Habibagahi, Ghassem
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GENETIC programming ,SANDY soils ,DATABASES ,GRAIN size ,X-ray imaging ,INTERFACIAL bonding ,HYDROLOGY ,POROSITY - Abstract
Understanding specific air–water interfacial area (SAWIA) is essential for characterizing and modeling various phenomena in vadose zone hydrology, such as virus and colloid transport, contaminant dissolution, evaporation, and the hydro‐mechanical behavior of unsaturated soils. Traditional measurement methods, including X‐ray imaging and tracer techniques, often encounter challenges, leading to a scarcity of studies that provide a reliable relationship for SAWIA. Currently, no pedotransfer function in the literature links SAWIA with saturation and suction using readily measurable soil properties such as median grain size and porosity. In this study, we initially developed a pore network model capable of predicting SAWIA by calibrating it with corresponding soil‐water retention curves (SWRCs). We then used these models to compile a comprehensive database of SAWIA for six sandy soils, for which experimental SWRCs were available, covering a range of median grain sizes and porosities. Utilizing this database, we established a pedotransfer function through multigene genetic programming. The accuracy of this function was validated against experimental data not previously used in its training and testing. Our parametric study indicated that increases in either porosity or median particle size led to a decrease in the regions exhibiting higher SAWIA in terms of saturation and suction. Core Ideas: Estimating the specific air–water interfacial area in different hydraulic branches using a pore network approach.Compiling a specific interfacial area database for soils with different values of porosity and median grain size.Using multigene‐genetic programming to extract a pedotransfer function for specific interfacial area.The proposed specific interfacial area pedotransfer function requires only soil median grain size and porosity. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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166. RoGeR v3.0.5 – a process-based hydrological toolbox model in Python.
- Author
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Schwemmle, Robin, Leistert, Hannes, Steinbrich, Andreas, and Weiler, Markus
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WATER management ,PYTHON programming language ,TRAVEL time (Traffic engineering) ,HYDROLOGIC models ,WATER supply ,SOFTWARE architecture - Abstract
Although water availability and water quality are equally important for effective water resources management at various spatial and temporal scales, to date, a combined representation of soil water balance components and water quality components in Python is not available. The new RoGeR toolbox contains models that can be used for not only the quantification of hydrological processes, fluxes and stores, but also solute transport processes based on StorAge selection (SAS). This study presents the code structure and functionalities of RoGeR developed as a scientific model toolbox following defined open-source software guidelines. RoGeR uses five different computational backends covering just-in-time compilation, parallelism and graphical processing units (GPUs) that might be used for optimizing computational performance. We show that graphical processing unit computing has the greatest potential to improve computation time and energy usage, especially for large modelling experiments. A simple modelling experiment highlights the capabilities of the new RoGeR model toolbox. We simulated the soil water balance, stable water isotope (18 O) transport, and corresponding travel time distributions of the Eberbaechle catchment, Germany, for a 3-year period. Due to the current limitations of a variety of process components, further development of RoGeR as a scientific software is needed. Future modifications are easily possible due to the open software architecture of RoGeR. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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167. Characterizing Climatic Socio‐Environmental Tipping Points in Coastal Communities: A Conceptual Framework for Research and Practice.
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Shortridge, J. E., Bukvic, A., Mitchell, M., Goldstein, J., and Allen, T.
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SEA level ,SOCIETAL reaction ,RISK assessment ,SOCIAL impact ,COMPARATIVE studies - Abstract
The concept of climate tipping points in socio‐environmental systems is increasingly being used to describe nonlinear climate change impacts and encourage social transformations in response to climate change. However, the processes that lead to these tipping points and their impacts are highly complex and deeply uncertain. This is due to numerous interacting environmental and societal system components, constant system evolution, and uncertainty in the relationships between events and their consequences. In the face of this complexity and uncertainty, this research presents a conceptual framework that describes systemic processes that could lead to tipping points socio‐environmental systems, with a focus on coastal communities facing sea level rise. Within this context, we propose an organizational framework for system description that consists of elements, state variables, links, internal processes, and exogenous influences. This framework is then used to describe three mechanisms by which socio‐environmental tipping could occur: feedback processes, cascading linkages, and nonlinear relationships. We presented this conceptual framework to an expert panel of coastal practitioners and found that it has potential to characterize the effects of secondary climatic impacts that are rarely the focus of coastal risk analyses. Finally, we identify salient areas for further research that can build upon the proposed conceptual framework to inform practical efforts that support climate adaptation and resilience. Plain Language Summary: In the face of climate change, there is growing concern that incremental adaptation measures will be insufficient in addressing climate risks. Socio‐environmental tipping points describe situations where a small change or pressure results in a societal system moving into a fundamentally different state. This concept is increasingly used to describe risks from climate change and the meaningful societal changes necessary to reduce these risks. However, understanding how climatic tipping points might unfold in socio‐environmental systems is very challenging because these systems are highly complex, with human, built, and environmental components that interact in unpredictable ways. This research presents a framework for describing tipping points in socio‐environmental systems, and uses this descriptive framework to identify three tipping point mechanisms. These are feedback processes, cascading linkages, and nonlinear relationships. A panel of coastal practitioners reviewed the framework and found that it could capture the multiple potential tipping points that they have found in their work. By developing a common way of describing climatic tipping points in socio‐environmental systems, this framework can support comparative studies across different locations and the development of computational models for exploring the impact of tipping points and potential interventions. Key Points: The study presents a conceptual framework of climate‐related tipping points in socio‐environmental systemsIt identifies and describe three tipping mechanisms: feedback processes, cascading linkages, and nonlinear relationshipsAn expert panel of coastal practitioners validated the framework and provided multiple examples of tipping points in practice [ABSTRACT FROM AUTHOR]
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- 2024
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168. Accumulation of soil phosphorus within closed depressions of a drained agricultural watershed.
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Mumbi, R. C. K., Williams, M. R., Penn, C. J., and Camberato, J. J.
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PHOSPHORUS in soils ,AGRICULTURAL landscape management ,AGRICULTURE ,MENTAL depression ,SOIL sampling ,WATERSHEDS - Abstract
Closed depressions are common landscape features across glaciated landscapes. Erosion and runoff from depression hillslopes may result in phosphorus (P) accumulation near the bottom of the depression, with this "legacy P" potentially at risk of loss to surface waters when drained via tile drainage. We assessed spatial patterns of soil P within a tile‐drained watershed in northeastern Indiana as a function of landscape position and agricultural management practices. Paired soil samples (depression bottom vs. hillslope contributing area) were collected from agricultural (n = 14) depressions at four depths (0–60 cm). Water‐extractable phosphorus (WEP), Mehlich‐3 extracted phosphorus (M3‐P), total phosphorus (TP), Hedley P fractions, and other physical and chemical characteristics were determined. To assess the risk of P loss, P desorption from surface soils (0–5 cm) was quantified using flow‐through experiments. Results showed that WEP, M3‐P, and TP were 2–10 times greater in the depression bottom compared to hillslopes across all depths. Long‐term management practices such as P application history and tillage influenced the magnitude of soil P concentration, degree of P saturation, and vertical stratification of soil P. Flow‐through experiments highlighted that the risk of P loss was highly dependent on M3‐P concentration for both hillslope and depression soils. Findings therefore indicate that closed depressions may act as hotspots for P cycling and loss in tile‐drained watersheds. Including low‐lying depressional areas as part of a routine soil sampling strategy combined with variable rate P application could lessen P accumulation in depressions and reduce P loading to surface waters. Core Ideas: Phosphorus accumulation in closed depressions of a tile‐drained watershed was assessed.WEP, Mehlich‐3 extracted phosphorus (M3‐P), and total P were significantly greater near the depression bottom compared to hillslopes.Topography and agricultural management influenced P accumulation within depressions.Phosphorus desorption during flow‐through experiments showed that P loss was dependent on M3‐P concentration.Soil sampling in depressions combined with variable rate P application could reduce the risk of P loss. [ABSTRACT FROM AUTHOR]
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- 2024
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169. Single quantum dots for slow and fast light in a planar photonic crystal
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Manga Rao, V. S. C. and Hughes, S.
- Abstract
We theoretically investigate slow and fast light propagation and pulse velocity control in a nanocavity containing a single quantum dot side-coupled to a planar-photonic-crystal waveguide. We demonstrate that low coupling strength (i.e., the weak coupling regime) between a cavity and a dot, under on-resonance condition, can lead to delays of about +90 ps for a pulse 1/e-width of 280 ps. The group delay dependence on the various coupling parameters suggests achievable delays of +300 ps and consequently very slow light speeds of around 5000 m/s in a 1.5 μm cavity-waveguide section. We also show that under off-resonant condition one can achieve significant pulse advancement of −60 ps.
- Published
- 2007
170. Atomic absorbers for controlling pulse propagation in resonators
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Manga Rao, V. S. C., Gupta, Subhasish Dutta, and Agarwal, Girish S.
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We consider pulse propagation through a Fabry–Perot cavity with silver mirrors that contain macroscopic samples of resonant absorbers. We show that the pulse velocity can be tuned from subluminal to superluminal in a strongly coupled atom–cavity system. We delineate the effects of the interplay of cavity and absorbers. We demonstrate the saturation effects of pulse advancement with increasing mirror thickness and atomic damping.
- Published
- 2004
171. Modelling hydrologic and geochemical filtering of reactive solute transport in catchments
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Rao, P. S. C., Basu, N. B., Zanarado, S., Ciaran Harman, Sivapalan, M., and Rinaldo, A.
172. Laboratory testing of temperature increases, surfactants and co-solvents as options to enhance dissolution in a brominated-solvent source zone
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Davis, G. B., Bastow, T. P., Johnston, C. D., Patterson, B. M., Annable, M. D., Rao, P. S. C., Geste, Y., Robert Woodbury, and Rhodes, S.
173. Resilience Dynamics of Urban Water Supply Security and Potential of Tipping Points
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Krueger, E. H., Borchardt, D., Jawitz, J. W., Klammler, H., Yang, S., Zischg, J., and Rao, P. S. C.
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13. Climate action ,11. Sustainability ,1. No poverty ,6. Clean water - Abstract
Cities are the drivers of socioeconomic innovation and are also forced to address the accelerating risk of failure in providing essential services such as water supply today and in the future. Here, we investigate the resilience of urban water supply security, which is defined in terms of the services that citizens receive. The resilience of services is determined by the availability and robustness of critical system elements or “capitals” (water resources, infrastructure, finances, management efficacy, and community adaptation). We translate quantitative information about this portfolio of capitals from seven contrasting cities on four continents into parameters of a coupled system dynamics model. Water services are disrupted by recurring stochastic shocks, and we simulate the dynamics of impact and recovery cycles. Resilience emerges under various constraints, expressed in terms of each city's capital portfolio. Systematic assessment of the parameter space produces the urban water resilience landscape, and we determine the position of each city along a continuous gradient from water insecure and nonresilient to secure and resilient systems. In several cities stochastic disturbance regimes challenge steady-state conditions and drive system collapse. While water insecure and nonresilient cities risk being pushed into a poverty trap, cities which have developed excess capitals risk being trapped in rigidity and crossing a tipping point from high to low services and collapse. Where public services are insufficient, community adaptation improves water security and resilience to varying degrees. Our results highlight the need for resilience thinking in the governance of urban water systems under global change pressures.
174. Dynamic spatio-temporal patterns of metapopulation occupancy in patchy habitats
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Bertassello, L. E., Botter, G., Jawitz, J. W., Aubeneau, A. F., Hoverman, J. T., Rinaldo, A., and Rao, P. S. C.
- Subjects
links ,capacity ,isolated wetlands ,metapopulation ,landscape connectivity ,persistence ,extinction thresholds ,populations ,ecohydrology ,wetlandscape ,models ,framework ,ecological networks ,stochastic modelling ,dispersal - Abstract
Spatio-temporal dynamics in habitat suitability and connectivity among mosaics of heterogeneous wetlands are critical for biological diversity and species persistence in aquatic patchy landscapes. Despite the recognized importance of stochastic hydroclimatic forcing in driving wetlandscape hydrological dynamics, linking such effects to emergent dynamics of metapopulation poses significant challenges. To fill this gap, we propose here a dynamic stochastic patch occupancy model (SPOM), which links parsimonious hydrological and ecological models to simulate spatio-temporal patterns in species occupancy in wetlandscapes. Our work aims to place ecological studies of patchy habitats into a proper hydrologic and climatic framework to improve the knowledge about metapopulation shifts in response to climate-driven changes in wetlandscapes. We applied the dynamic version of the SPOM (D-SPOM) framework in two wetlandscapes in the US with contrasting landscape and climate properties. Our results illustrate that explicit consideration of the temporal dimension proposed in the D-SPOM is important to interpret local- and landscape-scale patterns of habitat suitability and metapopulation occupancy. Our analyses show that spatio-temporal dynamics of patch suitability and accessibility, driven by the stochasticity in hydroclimatic forcing, influence metapopulation occupancy and the topological metrics of the emergent wetlandscape dispersal network. D-SPOM simulations also reveal that the extinction risk in dynamic wetlandscapes is exacerbated by extended dry periods when suitable habitat decreases, hence limiting successful patch colonization and exacerbating metapopulation extinction risks. The proposed framework is not restricted only to wetland studies but could also be applied to examine metapopulation dynamics in other types of patchy habitats subjected to stochastic external disturbances.
175. Treating constipation with bile: a new target
- Author
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Rao, Satish S C
- Published
- 2018
- Full Text
- View/download PDF
176. Reply to Comments on “Factors Influencing Oxygen Consumption Rates in Flooded Soils”
- Author
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Reddy, K. R., primary, Rao, P. S. C., additional, and Patrick, W. H., additional
- Published
- 1981
- Full Text
- View/download PDF
177. Adsorption of Diuron and 2,4,5‐T on Soil Particle‐Size Separates
- Author
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Nkedi‐Kizza, P., primary, Rao, P. S. C., additional, and Johnson, Jennifer W., additional
- Published
- 1983
- Full Text
- View/download PDF
178. Influence of organic cosolvents on sorption of hydrophobic organic chemicals by soils
- Author
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Nkedi-Kizza, P., primary, Rao, P. S. C., additional, and Hornsby, A. G., additional
- Published
- 1985
- Full Text
- View/download PDF
179. Nonequilibrium Conditions for Ammonium Adsorption-desorption During Flow in Soils
- Author
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Rao, P. S. C., primary and Davidson, J. M., additional
- Published
- 1978
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- View/download PDF
180. Residue Reviews, Volume 80
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Rao, P. S. C., primary, Wheeler, W. B., additional, and Neary, D. G., additional
- Published
- 1982
- Full Text
- View/download PDF
181. Pertinent Criteria for Describing the Dissolution of Gypsum Beds in Flowing Water
- Author
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Keisling, T. C., primary, Rao, P. S. C., additional, and Jessup, R. E., additional
- Published
- 1978
- Full Text
- View/download PDF
182. Estimation of the Spatial Variability of the Soil-Water Flux
- Author
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Rao, P. S. C., primary, Rao, P. V., additional, and Davidson, J. M., additional
- Published
- 1977
- Full Text
- View/download PDF
183. Degradation and metabolism of Oxamyl and phenamiphos in soils
- Author
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Ou, L. -T., primary and Rao, P. S. C., additional
- Published
- 1986
- Full Text
- View/download PDF
184. A stochastic approach for describing convective‐dispersive solute transport in saturated porous media
- Author
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Rao, P. V., primary, Portier, K. M., additional, and Rao, P. S. C., additional
- Published
- 1981
- Full Text
- View/download PDF
185. SIMULATION OF DENITRIFICATION LOSSES OF NITRATE FERTILIZER APPLIED TO UNCROPPED, CROPPED, AND MANURE-AMENDED FIELD PLOTS
- Author
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ROLSTON, D. E., primary, RAO, P. S. C., additional, DAVIDSON, J. M., additional, and JESSUP, R. E., additional
- Published
- 1984
- Full Text
- View/download PDF
186. Divergence Between Long‐Term and Event‐Scale Nitrate Export Patterns.
- Author
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Winter, Carolin, Jawitz, James W., Ebeling, Pia, Cohen, Matthew J., and Musolff, Andreas
- Subjects
NITRATES ,AGRICULTURE ,DATA analysis - Abstract
The mechanisms driving catchment nitrogen storage and release operate at multiple spatiotemporal scales. Consequently, analyses grounded in different observational timescales can yield discrepant interpretations of underlying mechanisms. To assess the consistency of nitrate export patterns between event‐ and inter‐annual scales, we evaluated multiple years of high‐frequency observations of nitrate concentrations (C) and discharge (Q) including 3,480 discrete discharge events from 28 dominantly agricultural catchments. We observed consistent and often drastic divergence between long‐term and median event‐specific C‐Q patterns. Most catchments showed long‐term enrichment patterns (positive C‐Q slope), but events were, on average, more chemostatic (close‐to‐zero C‐Q slopes). C‐Q slope variability was high for small events but decreased with event magnitude, approaching chemostatic patterns during the largest storms, yielding compelling evidence against nitrate source limitation. We conclude that nitrate export patterns observed at different temporal scales and event magnitudes are controlled by different processes, therefore embedding complementary information. Plain Language Summary: Storage and mobilization of nitrogen in the landscape ultimately shape nitrate concentration dynamics in streams and their transport to downstream receiving waters. However, the temporal resolution of data analyses (e.g., long‐term or high‐flow events) can affect the interpretation of nitrate export from catchments and underlying mechanisms. To test whether nitrate export patterns differ between event and long‐term time scales, we evaluated several years of daily observations of nitrate concentration and discharge, including 3,480 high‐flow events from 28 dominantly agricultural catchments. We observed consistent and often drastic divergence between long‐term and average event‐specific export patterns. The variability in export patterns between events decreased with event magnitude toward patterns that indicate no nitrogen source limitation. Nitrate export patterns are regulated by different controls depending on the temporal scale of analysis, which must be considered to avoid incomplete and misleading interpretations about the underlying mechanisms. Key Points: Long‐term and event‐scale nitrate export patterns diverge, pointing at complementary drivers of catchment functioning across time scalesEvent‐scale C‐Q slopes decreased in variability with event magnitude and showed no signs of source limitation at high‐magnitude eventsMulti‐catchment high‐frequency data revealed the crucial role of time scale and event magnitude for interpreting nitrate export patterns [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
187. Levee system transformation in coevolution between humans and water systems along the Kiso River, Japan.
- Author
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Nakamura, Shinichiro, Nakai, Fuko, Ito, Yuichiro, Okada, Ginga, and Oki, Taikan
- Subjects
LEVEES ,COEVOLUTION ,HOMINIDS ,WATER use ,FLOODPLAINS - Abstract
Floodplain societies decide whether to protect themselves against floods (fight), live with floods (adapt), or adopt an approach that represents some combination of the two. The formation of a levee system is an important factor in determining whether a society fights or adapts to floods; however, these factors have been considered fixed boundaries in previous studies in human–flood interactions. We analyze a levee system transformation process covering the past century, from the indigenous ring-type levee system with floods to modern continuous levees against floods in the Kiso River basin in Japan by applying a historical sociohydrological approach. The results show degradation processes of the indigenous levee system and traditional communities alongside the installation of modern continuous levees, and a trade-off relationship was observed between the lengths of both. There are interactions between the levee systems and the human–water system through various water uses and different-scale components, and the dynamics within the region are connected to external socioeconomic trends through the installed modern levees and institutions. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
188. APLICAÇÃO DE ANÁLISE ESTATÍSTICA PARA VALIDAÇÃO DE PARÂMETROS NA MEDIÇÃO DE DESEMPENHO DA VULNERABILIDADE DA REDE VIÁRIA.
- Author
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Dantas dos Santos, João Evangelista and Vieira Bertoncini, Bruno
- Subjects
TRAVEL time (Traffic engineering) ,LITERATURE reviews ,HIGHWAY planning ,CITIES & towns ,DESCRIPTIVE statistics - Abstract
Copyright of Brazilian Journal of Production Engineering / Revista Brasileira de Engenharia de Produção is the property of Brazilian Journal of Production Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2024
- Full Text
- View/download PDF
189. Greenery hypothesis: An evolutionary explanation for why presence/absence of green affects humans.
- Author
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Fukano, Yuya and Soga, Masashi
- Subjects
BIODIVERSITY conservation ,URBAN planning ,CONSERVATION & restoration ,HYPOTHESIS ,BIOPHILIA hypothesis - Abstract
A growing body of empirical evidence shows that experiences of nature provide people with diverse psychological benefits, including improved cognitive function and mental health. While our understanding of the proximate causes of these positive psychological responses of humans to nature has advanced, the ultimate (evolutionary) drivers behind them remain poorly understood.In this study, we provide a summary of several widely accepted evolutionary hypotheses originating from Biophilia, reviewing their challenges and limitations. Subsequently, we propose a new evolutionary psychological hypothesis—the greenery hypothesis—that integrates recent findings in evolutionary psychiatry with many experimental results unexplained by existing hypotheses/theories.Our proposed hypothesis states that humans have adapted to periodic severe drought and re‐watering cycles by developing both negative and positive psychological responses to the absence or presence of greenery within the landscape as cues to optimise their own behavioural activity.The greenery hypothesis holds the potential to yield several insights into the fundamental understanding of human psychological responses to nature exposure with significant implications for various related fields, including psychiatry, urban planning, and biodiversity conservation and restoration. Read the free Plain Language Summary for this article on the Journal blog. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
190. Microbial mediated carbon and nitrogen cycling in the spatially heterogeneous vadose zone: A modeling study.
- Author
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Khurana, Swamini, Heße, Falk, Hildebrandt, Anke, and Thullner, Martin
- Subjects
NITROGEN cycle ,CARBON cycle ,SPATIAL variation ,MICROBIAL communities ,MICROORGANISMS - Abstract
Spatially distributed properties of the subsurface result in varying water saturation and preferential flow paths, which lead to heterogeneous solute transport patterns and heterogeneous microbial environments. This, in turn, influences the distribution of nutrients and energy gradients, microbial biomass, and activity thereof. By their very nature, current field sampling techniques do not resolve subsampling scale heterogeneities in microbial biomass and activity, resulting in inaccurate estimates of microbially mediated carbon and nitrogen turnover in the heterogeneous subsurface. Thus, in this study, we undertook a numerical modeling approach to study the impact of spatial heterogeneity on microbially mediated carbon and nitrogen turnover in the vadose zone. We adapted an established biogeochemical process network that captures a variety of respiration pathways, carbon decomposition strategies, and microbial life processes to simulate microbially mediated carbon and nitrogen turnover in variably saturated spatially heterogeneous settings, using an established numerical tool (OGS#BRNS). The fractionation of microbial communities into active and inactive states, as well as immobile and mobile states followed could be linked to the bulk average saturation. Lastly, we identified three reactive systems, distinguished by the rate ratio of aerobic respiration and transfer of oxygen from the air to the water phase, to evaluate the impact of spatial heterogeneity on carbon and nitrogen removal in subsurface heterogeneous domains. Specifically, when this ratio is approximately 1, there is no impact on carbon removal, while when this ratio is very high, then carbon removal decreases as the domain tends to be oxygen limited. Core Ideas: Spatial heterogeneity leads to spatial variation of saturation in the vadose zone.Spatial heterogeneity leads to variation in the distribution of nutrients in the subsurface.The saturation and flow regime of a subsurface system influence the play‐off between respiration and aeration.Aeration may cause a homogenization effect in spatially heterogeneous domains.The location and activity of microbes can be predicted using average saturation and flow regime. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
191. Soil nitrate nitrogen levels as an index of nitrogen fertilizer needs of sugarbeets
- Author
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Reuss, J. O., primary and Rao, P. S. C., additional
- Published
- 1971
- Full Text
- View/download PDF
192. Current Applications and Future Trends of Artificial Intelligence and Machine Learning in the Resilience of Interdependent Critical Infrastructures.
- Author
-
Alkhaleel, Basem A.
- Subjects
ARTIFICIAL intelligence ,MACHINE learning ,META-analysis ,ENGINEERING ,WATER supply - Abstract
Critical infrastructures, such as power and water networks, are vital for society and the economy. However, they are vulnerable to various disruptions such as component failures, cyber-attacks, and natural disasters. These disruptions can cascade across critical infrastructure networks (CINs), causing significant socioeconomic losses. Decision-makers face the challenge of protecting CINs before disruptions and restoring their functions afterward, considering interdependencies and uncertainties. Current methods struggle to model big data, complex interactions, and multilayer dependencies between CINs. Artificial intelligence (AI) and machine learning (ML) applications can be used to overcome these challenges, as they can model complex systems and discover data patterns representing a promising research trend that could benefit both private companies and governments. This article undertakes a comprehensive review of the literature on the applications of machine learning in improving the resilience of interdependent critical infrastructure systems (ICISs). The aim is to address the existing knowledge gap and dispersed research articles in this area, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol. The primary goal of this article is to assess the current state of ML applications in the ICISs resilience engineering field by examining the available literature, in order to discover future opportunities and trends. The findings are summarized, and potential future trends and opportunities are listed, aiming to inspire resilience engineering practitioners to explore these future directions in the field. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
193. Pneumoperitoneum and Ascites Secondary to Bacterial Overgrowth
- Author
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Raju, G. S., Rao, Satish S. C., and Lu, C.
- Abstract
Abdominal bloating, weight loss, pneumoperitoneum, and ascites developed in a 73-year-old woman. She had scleroderma, megajejunum, small bowel dysmotility, and bacterial overgrowth. After treatment with a course of antibiotics, the pneumoperitoneum and ascites resolved, but her symptoms and the pneumoperitoneum recurred after the antibiotics were stopped. She was placed on cyclical antibiotics, and during a 2-year follow-up period she has remained well. The pneumoperitoneum and ascites may have been secondary to small bowel bacterial overgrowth. Ours is the first case that demonstrates this association.
- Published
- 1997
194. A Total Synthesis of (±)-Trichodiene
- Author
-
Rao, A. S. C. P., Wong, R. Y., and Welch, S. C.
- Abstract
Trichodiene (1), a sesquiterpene hydrocarbon, was isolated from the extract of mycelium of Trichothecium roseum. The structure of trichodiene (1) was elucidated by Nozoe and Machida in 1970 via degradation and spectroscopy.1 Trichodiene (1) has been shown to be the biogenetic precursor of the trichothecane family of sesquiterpenoids as characterized by the cytotoxic fungal metabolite (-)-trichodermin (2).2,3 The structure and absolute stereochemistry of (-)-trichodermin (2) were determined by X-ray diffraction and, therefore, the structure and absolute stereochemistry of trichodiene (1) are now firmly established.4 We wish to report a total synthesis of (±)-trichodiene (1) via previously reported lactone 3.5,6
- Published
- 1976
- Full Text
- View/download PDF
195. Evaluating soil quality and carbon storage in Western Ghats Forests, Karnataka, India, for sustainable forest management.
- Author
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Saha K, Kumar KSA, Nair KM, Lalitha M, Das P, Maske SP, Jacob PJ, Jessy MD, Karthika KS, Ramamurthy V, and Patil NG
- Subjects
- India, Carbon Sequestration, Conservation of Natural Resources methods, Ecosystem, Forests, Soil chemistry, Environmental Monitoring, Carbon analysis, Forestry
- Abstract
Monitoring soil quality index (SQI) and soil organic carbon (SOC) stock status of the Western Ghats (WG) forests in India is crucial for providing vital ecosystem services alongside sustainable forest management practices. However, comprehensive profile data on SQI and SOC stock across different forest types under WG forests are limited. The study evaluated SQI and SOC stock under three forest types, i.e. tropical wet evergreen (TWE), tropical semi-evergreen (TSE), and tropical moist deciduous (TMD) across WG in Karnataka. SQI was assessed using principal component analysis with two indexing approaches and scoring methodologies, with weightage indexing through nonlinear scoring functions (NLSF) showing superiority over other methodologies. TMD forests exhibited the highest SQI, followed by TWE and TSE, while the lowest was observed in Rippon Pet RF (0.36 surface, 0.28 control section), primarily due to limitations in organic carbon and clay content. SOC stock mirrored SQI trends (TMD > TWE > TSE), with the highest values in Kollegal RF (339.3 MG ha
-1 ) and lowest in Rippon Pet RF (102.5 MG ha-1 ). Although SOC and SQI were established to be ideal indicators for dynamic ecosystem services (ESs), high OC content in surface soils of Poomale NF induces pedogenic acidification and Al toxicities, indicating potential forest soil degradation. Significant correlation with control section SQI and SOC (p < 0.05) emphasises monitoring subsurface soil status to identify soil degradation, sustainable forestry practices, and complex ESs in forest systems., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)- Published
- 2024
- Full Text
- View/download PDF
196. High-resolution multi-scaling of outdoor human thermal comfort and its intra-urban variability based on machine learning.
- Author
-
Briegel, Ferdinand, Wehrle, Jonas, Schindler, Dirk, and Christen, Andreas
- Subjects
THERMAL comfort ,HUMAN comfort ,MACHINE learning ,CLIMATIC zones ,URBAN climatology ,URBAN plants ,URBAN trees ,ATMOSPHERIC temperature - Abstract
As the frequency and intensity of heatwaves will continue to increase in the future, accurate and high-resolution mapping and forecasting of human outdoor thermal comfort in urban environments are of great importance. This study presents a machine-learning-based outdoor thermal comfort model with a good trade-off between computational cost, complexity, and accuracy compared to common numerical urban climate models. The machine learning approach is basically an emulation of different numerical urban climate models. The final model consists of four submodels that predict air temperature, relative humidity, wind speed, and mean radiant temperature based on meteorological forcing and geospatial data on building forms, land cover, and vegetation. These variables are then combined into a thermal index (universal thermal climate index – UTCI). All four submodel predictions and the final model output are evaluated using street-level measurements from a dense urban sensor network in Freiburg, Germany. The final model has a mean absolute error of 2.3 K. Based on a city-wide simulation for Freiburg, we demonstrate that the model is fast and versatile enough to simulate multiple years at hourly time steps to predict street-level UTCI at 1 m spatial resolution for an entire city. Simulations indicate that neighbourhood-averaged thermal comfort conditions vary widely between neighbourhoods, even if they are attributed to the same local climate zones, for example, due to differences in age and degree of urban vegetation. Simulations also show contrasting differences in the location of hotspots during the day and at night. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
197. CAMELS-Chem: augmenting CAMELS (Catchment Attributes and Meteorology for Large-sample Studies) with atmospheric and stream water chemistry data.
- Author
-
Sterle, Gary, Perdrial, Julia, Kincaid, Dustin W., Underwood, Kristen L., Rizzo, Donna M., Haq, Ijaz Ul, Li, Li, Lee, Byung Suk, Adler, Thomas, Wen, Hang, Middleton, Helena, and Harpold, Adrian A.
- Subjects
STREAM chemistry ,WATER chemistry ,METEOROLOGY ,ATMOSPHERIC deposition ,LAND cover ,CAMELS ,RELATIONAL databases - Abstract
Large sample datasets are transforming the catchment sciences, but there are few off-the-shelf stream water chemistry datasets with complementary atmospheric deposition, streamflow, meteorology, and catchment physiographic attributes. The existing CAMELS (Catchment Attributes and Meteorology for Large-sample Studies) dataset includes data on topography, climate, streamflow, land cover, soil, and geology across the continental US. With CAMELS-Chem, we pair these existing attribute data for 516 catchments with atmospheric deposition data from the National Atmospheric Deposition Program and water chemistry and instantaneous discharge data from the US Geological Survey over the period from 1980 through 2018 in a relational database and corresponding dataset. The data include 18 common stream water chemistry constituents: Al, Ca, Cl, dissolved organic carbon, total organic carbon, HCO 3 , K, Mg, Na, total dissolved N, total organic N, NO 3 , dissolved oxygen, pH (field and lab), Si, SO 4 , and water temperature. Annual deposition loads and concentrations include hydrogen, NH 4 , NO 3 , total inorganic N, Cl, SO 4 , Ca, K, Mg, and Na. We demonstrate that CAMELS-Chem water chemistry data are sampled effectively across climates, seasons, and discharges for trend analysis and highlight the coincident sampling of stream constituents for process-based understanding. To motivate their use by the larger scientific community across a variety of disciplines, we show examples of how these publicly available datasets can be applied to trend detection and attribution, biogeochemical process understanding, and new hypothesis generation via data-driven techniques. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
198. The role of sharia microfinance institutions in developing MSMEs.
- Author
-
Isfianadewi, Dessy
- Subjects
BUSINESS development ,MICROFINANCE ,SMALL business ,ISLAMIC law ,ENTREPRENEURSHIP - Abstract
This study aims to investigate and identify the current conditions regarding the role of Sharia microfinance institutions in developing MSME businesses. The community needs Microfinance institutions, especially low-income groups and small and micro-entrepreneurs who have yet to be reached by banking financial services, especially public banks. In providing loans to MSMEs, microfinance institutions must effectively educate and equip their clients with relevant entrepreneurial knowledge and skills. This research will use a qualitative approach with a case study method, which does not use statistical generalizations but uses logical generalizations and replication. Three Sharia microfinance institutions and sixteen MSME cases will be selected in this research. The research was conducted at Sharia Microfinance Institutions as providers of microcredit and MSMEs receiving microcredit in the Southern region of the Special Region of Yogyakarta, Gunungkidul, and Kulonprogo. This research will use three data collection methods, namely interviews, observation, and documentation, to maintain the validity and reliability of the data. Data triangulation is used to test the validity of the data. The data analysis process in this research uses two stages: descriptive analysis and case analysis. The findings of this research show hope regarding the promise of easy access to capital or funding sources as an effective tool for improving MSME business development through effectiveness, supervision, and guidance carried out by Sharia microfinance institutions. This change can be realized if the community has economic stability obtained through easy access to capital, increasing business income, and empowering the community to be ready to become entrepreneurs. It supports the development of a creative economy industry based on entrepreneurship and globally competitive ethics. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
199. An assessment of potential improvements in social capital, risk awareness, and preparedness from digital technologies.
- Author
-
Piseddu, Tommaso, Englund, Mathilda, and Barquet, Karina
- Subjects
RISK perception ,DIGITAL technology ,SOCIAL capital ,EMERGENCY management ,PREPAREDNESS ,REMOTE-sensing images - Abstract
Contributions to social capital, risk awareness, and preparedness constitute the parameters against which applications of digital technologies in the field of disaster risk management should be tested. We propose here an evaluation of four of these: mobile positioning data, social media crowdsourcing, drones, and satellite imaging, with an additional focus on acceptability and feasibility. The assessment is carried out through a survey disseminated among stakeholders. The frame of the analysis also grants the opportunity to investigate to what extent different methodologies to aggregate and evaluate the results, i.e., the Criteria Importance Through Criteria Correlation (CRITIC) model, the (Euclidean)-distance Criteria Importance Through Criteria Correlation (dCRITIC) model, the entropy model, the mean weight model, and the standard deviation model, may influence the preference of one technology over the others. We find that the different assumptions on which these methodologies rely deliver diverging results. We therefore recommend that future research adopt a sensitivity analysis that considers multiple and alternatives methods to evaluate survey results. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
200. Assessment of business resilience abilities: the case of industry and commerce of Santa Maria - RS.
- Author
-
Valau Soares, Matheus Pedroso and Soliman, Marlon
- Subjects
SAMPLING (Process) ,ORGANIZATIONAL resilience ,ECONOMIC sectors ,RESEARCH personnel ,SAMPLE size (Statistics) - Abstract
Copyright of Brazilian Journal of Management / Revista de Administração da UFSM is the property of Brazilian Journal of Management / Revista de Administracao da UFSM and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2024
- Full Text
- View/download PDF
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