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Barton, Samantha. "Emptying reservoirs of latent HIV-1". Nature Reviews Drug Discovery 4, n.º 11 (24 de outubro de 2005): 886. http://dx.doi.org/10.1038/nrd1888.
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Smith, Nicholas M., Hossein Ebrahimi, Ranajay Ghosh e Andrew K. Dickerson. "High-speed microjets issue from bursting oil gland reservoirs of citrus fruit". Proceedings of the National Academy of Sciences 115, n.º 26 (11 de junho de 2018): E5887—E5895. http://dx.doi.org/10.1073/pnas.1720809115.
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The rupture of oil gland reservoirs housed near the outer surface of the citrus exocarp is a common experience to the discerning citrus consumer and bartenders the world over. These reservoirs often rupture outwardly in response to bending the peel, which compresses the soft material surrounding the reservoirs, the albedo, increasing fluid pressure in the reservoir. Ultimately, fluid pressure exceeds the failure strength of the outermost membrane, the flavedo. The ensuing high-velocity discharge of oil and exhaustive emptying of oil gland reservoirs creates a method for jetting small quantities of the aromatic oil. We compare this jetting behavior across five citrus hybrids through high-speed videography. The jetting oil undergoes an extreme acceleration to reach velocities in excess of 10 m/s. Through material characterization and finite element simulations, we rationalize the combination of tuned material properties and geometries enabling the internal reservoir pressures that produce explosive dispersal, finding the composite structure of the citrus peel is critical for microjet production.
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Shagapov, V. Sh, e G. Ya Galeeva. "The emptying of channels and reservoirs accompanied by boiling". High Temperature 48, n.º 3 (junho de 2010): 388–96. http://dx.doi.org/10.1134/s0018151x10030132.
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Mohafid, Said, Laila Stour e Ali Agoumi. "Quantitative assessment of sedimentation in Moroccan dam reservoirs: analysis and projections". Multidisciplinary Science Journal 6, n.º 7 (13 de janeiro de 2024): 2024105. http://dx.doi.org/10.31893/multiscience.2024105.
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The siltation of dam reservoirs is the phenomenon that most embarrasses dam managers and water reservoir operators. In Morocco, this phenomenon affects all the watersheds to different degrees. Dam managers schedule bathymetric measurement companies to estimate the quantities of mud deposited in reservoirs. These companies are neither regular in time nor generalized on the 152 large dams of the Kingdom because of the high cost of the bathymetry operations. In our research work, the bathymetric data available for about a century were collected, checked, corrected, and sorted to be exploited.In the next step, we extrapolated over time and updated the siltation rates for each dam according to the trend curves of the evolution of silted volume. Most of these trend curves were linear. For the nonlinear curves, we looked for explanations throughout history. These are dams whose reservoirs have undergone human intervention such as desilting operations or emptying of reservoirs, or following natural phenomena such as drought or exceptional floods. The research work subsequently made it possible to estimate the annual siltation rates for 53 large dams whose reservoir capacities total approximately 92% of that of the entire country. It also revealed an overall siltation rate of 18.14% for the entire country and rates ranging from 10% to 52% for each watershed. The discussions of these results in this article give explanations on the highest rates, based on the natural data of the watersheds in question. These results will help decision-makers to define the priorities of desilting operations or the construction of new dams, help investors and industrialists wishing to extract and use mud from dam reservoirs as raw material, and can also be used in various scientific fields such as dam reservoir management, flood risk prevention, environmental impact studies, spatial planning, and research and development studies.
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Mhiribidi, Delight, Joel Nobert, Webster Gumindoga e Donald T. Rwasoka. "Optimal water resource allocation modelling in the Lowveld of Zimbabwe". Proceedings of the International Association of Hydrological Sciences 378 (29 de maio de 2018): 67–72. http://dx.doi.org/10.5194/piahs-378-67-2018.
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Abstract. The management and allocation of water from multi-reservoir systems is complex and thus requires dynamic modelling systems to achieve optimality. A multi-reservoir system in the Southern Lowveld of Zimbabwe is used for irrigation of sugarcane estates that produce sugar for both local and export consumption. The system is burdened with water allocation problems, made worse by decommissioning of dams. Thus the aim of this research was to develop an operating policy model for the Lowveld multi-reservoir system.The Mann Kendall Trend and Wilcoxon Signed-Rank tests were used to assess the variability of historic monthly rainfall and dam inflows for the period 1899–2015. The WEAP model was set up to evaluate the water allocation system of the catchment and come-up with a reference scenario for the 2015/2016 hydrologic year. Stochastic Dynamic Programming approach was used for optimisation of the multi-reservoirs releases.Results showed no significant trend in the rainfall but a significantly decreasing trend in inflows (p < 0.05). The water allocation model (WEAP) showed significant deficits ( ∼ 40 %) in irrigation water allocation in the reference scenario. The optimal rule curves for all the twelve months for each reservoir were obtained and considered to be a proper guideline for solving multi- reservoir management problems within the catchment. The rule curves are effective tools in guiding decision makers in the release of water without emptying the reservoirs but at the same time satisfying the demands based on the inflow, initial storage and end of month storage.
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Ari Wulandari, Dyah, Suseno Darsono e Dwi Kurniani. "Optimization of Gunungrowo Reservoir operation". MATEC Web of Conferences 270 (2019): 04016. http://dx.doi.org/10.1051/matecconf/201927004016.
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Inaccurate water release has occurred from Gunungrowo Reservoir. In May–June, there is excess water release from Gunungrowo Reservoir while in the period from July to August there is a shortage of water release. Therefore the reservoir operation should be evaluated and updated in order to obtain optimal results and to adjust the changes. The purpose of this study was to evaluate the existing reservoir operation and to carry out an optimization to find the optimal reservoir operation. The objective is to conduct hydrological analysis, evaluate the reservoir operation, formulate a model of reservoir operation, optimize the reservoir operation, and analyse the results of reservoir operation optimization. Optimization of reservoir operation generates the water level of reservoirs and the release of water in each period as well as the objective function value under each scenario of reservoir operation. The existing reservoir operation is not optimal and has a reliability of only 24%. In the operation of the existing reservoir, emptying of the reservoir storage always happens and inaccuracies in the release of water have occurred. The optimal reservoir operation is scenario I, with a reliability of 75%, in which water is released in Planting Season II and Planting Season III.
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Al-Amoud, A. I., H. M. Hathoot e F. S. Mohammad. "On the Estimation of the Time Required for Emptying Cylindrical Reservoirs Connected to Pipes". Journal of King Saud University - Engineering Sciences 9, n.º 1 (1997): 129–43. http://dx.doi.org/10.1016/s1018-3639(18)30671-8.
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Menéndez, Javier, e Jorge Loredo. "Numerical modelling of water subsurface reservoirs during the operation phase in underground pumped storage hydropower plants". E3S Web of Conferences 152 (2020): 02001. http://dx.doi.org/10.1051/e3sconf/202015202001.
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Underground pumped storage hydropower (UPSH) plants may be an alternative to store subsurface energy with lower environmental impacts than conventional pumped storage hydropower (PSH) plants. Network of tunnels in closed mines (i.e. coal mines) could be used as water lower reservoir of UPSH plants. The amount of storable energy depends on the water mass and the net head between upper and lower reservoirs. Depending on the direction of the water flow rate, pumping or turbine modes may be used to produce or consume electrical energy. Filling and emptying processes during the operation stage in the underground reservoir are complicated due to the presence of two fluids (water and air) interacting inside the network of tunnels. This paper explores the underground reservoir during the operation stage considering a water flow rate of 55 m3s-1. Two-phase three dimensional CFD numerical models using Ansys Fluent have been developed in order to know the behaviour of the air flow on tunnels and ventilation shaft. Static pressure and air velocity have been analyzed in the simulations at the exit of the ventilation shaft as well as the junction zone between the ventilation shaft and the tunnels network. The results obtained show that a static pressure up to 8,600 Pa and air velocities up to 80 m s-1 could be reached in turbine mode considering a vent shaft with 1 m in diameter. The static pressure increases up to 258,000 Pa if a ventilation shaft of 0.5 m in diameter is considered.
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Dumka, Rakesh, Pallabee Choudhury, V. K. Gahalaut, Kalpna Gahalaut e Rajeev Kumar Yadav. "GPS Measurements of Deformation Caused by Seasonal Filling and Emptying Cycles of Four Hydroelectric Reservoirs in India". Bulletin of the Seismological Society of America 108, n.º 5B (25 de setembro de 2018): 2955–66. http://dx.doi.org/10.1785/0120170355.
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Bakiev, Masharif, Shakhnoza Djabbarova e Khojiakbar Khasanov. "Determination of the time of lowering depression surface in transition zones with a smooth and instantaneous decrease in water level in reservoir". E3S Web of Conferences 365 (2023): 03014. http://dx.doi.org/10.1051/e3sconf/202336503014.
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The Republic of Uzbekistan pays great attention to the development and implementation of a program for the development of hydropower based on ensuring the share of hydropower in the energy potential and the integrated development of hydropower potential. Over the last three years, hydropower plants have been built or reconstructed in more than a dozen small and medium-sized earth dams to accomplish this task. Typically, unstable filtration is observed in the body of earth dams because of deviations from the normal filling and emptying of water reservoirs. The main goal of the research is to determine the time to lower the depression surface in the Tupalang earth dam transition zones, which characterizes the intensity of unstable filtration during a smooth and sudden drop in reservoir water level. The calculations were made according to the theoretical dependences of V.P.Nedriga for two cases of smooth and sudden lowering of the water level in the reservoir, starting from the normal backed level (NBL). In the calculations, the values of the main parameters were taken to be the coefficient of water loss of the soil (0.3), the coefficient of filtration of the transition zones (9.5 m/day), and the coefficient of laying the slope of the transition zones (0.2). Calculations showed that the time of lowering the depression surface in the transition zones with a gradual decrease in the water level in the reservoir was 84.1 days, and with an instantaneous decrease in the water level during the operation of a dam with a height of 120 m 3.86 days, and during the operation of a dam with a height of 185 m 6.82 days.
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Velychko, Svitlana, Olena Dupliak e Tetiana Kurbanova. "SLOPE STABILITY ASSESSMENT OF THE UPSTREAM SLOPE OF THE DRY MOUNTAIN FLOOD CONTROL RESERVOIR DURING THE FLOOD". Problems of Water supply, Sewerage and Hydraulic, n.º 37 (12 de dezembro de 2021): 4–12. http://dx.doi.org/10.32347/2524-0021.2021.37.4-12.
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The flood control is one of the priority goal for successful economic activity on the areas that are periodically suffer from floods. Such areas are the mountainous regions of the Ukrainian Carpathian Mountains. Floods on the mountain rivers are repeated several times each year, and are characterized by the sudden water level rise with almost the same rapid decrease of the water level. Active flood protection measures include dry mountain flood control reservoirs, the principle of which is to transform part of the flood runoff and to accumulate water for the short time in the the artificial reservoir, with followed rapid emptying to the minimum level. The complex hydraulic regime is formed in the body of the dam which forms the flood control reservoir during the flood, that is different from the operation of the water permanent reservoir. The design of the flood control structures is car-ried out in accordance with Ukrainian building codes for the construction of the water reservoirs with constant water level, and require testing the stability of the downstream slope for the maximum water levels under steady state seepage conditions and assessment the upstream slope stability during the water level decreasing from the maximum level calculated in the steady state condition, these calculations do not correspond to the real seepage processes in the body of the dam of the dry flood control reservoir. Therefore, the purpose of this work is to determine the necessary boundary conditions of the flood control reservoir operation and upstream slope stability assessment by the limit equilibrium method. In the article the operation of the dry mountain flood control reservoir was analysed and found that the dam was characterized by two states: dry reservoir with water minimum water level and variable position of the seepage curve in the core and the upstream prism during the flood. The main factors influencing the upstream slope stability are the physical and mechanical properties of the soil, the laying of the slope, the period of time when the high-water level is maintained and the intensity of water level dropping. The upstream slope stability was evaluated by the Morgenstern & Price and Ordinary methods on the Slope/w software package. After the first 25 hours of the flood (period of high-water levels and the next water level dropping) the Safety Factor evaluated by limit equilibrium methods began to decrease, and reached the minimum value during the greatest seepage curve gradients at the time between 45 and 50 hours. Slope stability calculations by the limit equilibrium method were compared with the results of calculations performed by the SRM method, the values of the Safety Factor and the way of their change during the flood evaluated by Ordinary and SRM methods almost coincide, which indicates the reliability of the results obtained by different methods of slope stability analysis
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Burszta-Adamiak, Ewa, e Janusz Łomotowski. "Modelling of percolation rate of stormwater from underground infiltration systems". Water Science and Technology 68, n.º 10 (25 de outubro de 2013): 2144–50. http://dx.doi.org/10.2166/wst.2013.467.
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Underground or surface stormwater storage tank systems that enable the infiltration of water into the ground are basic elements used in Sustainable Urban Drainage Systems (SUDS). So far, the design methods for such facilities have not taken into account the phenomenon of ground clogging during stormwater infiltration. Top layer sealing of the filter bed influences the infiltration rate of water into the ground. This study presents an original mathematical model describing changes in the infiltration rate variability in the phases of filling and emptying the storage and infiltration tank systems, which enables the determination of the degree of top ground layer clogging. The input data for modelling were obtained from studies conducted on experimental sites on objects constructed on a semi-technological scale. The experiment conducted has proven that the application of the model developed for the phase of water infiltration enables us to estimate the degree of module clogging. However, this method is more suitable for reservoirs embedded in more permeable soils than for those located in cohesive soils.
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Heppell, Jacques. "Intestinal Motility after Ileal Pouch-Anal Anastomosis". Canadian Journal of Gastroenterology 4, n.º 7 (1990): 432–35. http://dx.doi.org/10.1155/1990/678614.
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Colectomy, mucosal proctectomy and ileal pouch-anal anastomosis, has become the procedure of choice for carefully selected patients with ulcerative colitis requiring surgery. Pathophysiological studies after the operation have led to a better understanding of the mechanisms of continence and to the development of new technology to study anorectal function. Manometric studies of the anal sphincter, ileal pouch and distal ileum have shown that the operation alters the mechanisms of continence. The maximal tolerable volume of distension of an ileal pouch often approximates that of a normal rectum and yet the functional outcome may differ from a well functioning ileorectal anastomosis. Many other factors influence the result of the operation. The influence of the pattern of motility of the proximal and distal small bowel has been evaluated. The ileal pouch accommodation to distension has been correlated to clinical outcome. Scintigraphic techniques were designed to study the relationship between motility, filling and emptying of the ileal reservoirs. Measures designed to slow intestinal transit, increase absorption and reduce stool output are under investigation.
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Lindinger, Michael Ivan. "Oral electrolyte supplementation and prevention of dehydration in horses". UK-Vet Equine 8, n.º 1 (2 de janeiro de 2024): 45–50. http://dx.doi.org/10.12968/ukve.2024.8.1.45.
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Dehydration is common in equine disciplines and can be avoided by effective oral rehydration strategies. Thermoregulatory loss of heat in horses requires sweating which, in turn, can result in considerable loss of water and electrolytes. Maintenance of hydration and prevention of dehydration requires the continuous replacement of lost electrolytes and water. The stomach and small intestine can function as reservoirs to facilitate the uptake of water and electrolytes consumed 1–2 hours prior to competitions, training and transport. Ions and water are rapidly absorbed in the small intestine and taken up by muscles and the skin, where they serve to replace losses resulting from muscle contraction and sweating. An effective electrolyte supplement replaces electrolytes in the proportion that they are lost through sweating; failure to do this results in an electrolyte imbalance. Electrolyte solution osmolality must be maintained at less than that of bodily fluids to promote gastric emptying and intestinal absorption. Palatability of the electrolyte supplement should be high, and horses should be trained to drink the solution voluntarily before any dehydrating event to try to prevent dehydration from occurring.
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Saad Omer, T. Z., S. E. Ahmed e A. Karimi. "OPTIMAL OPERATION OF MULTIPURPOSE RESERVOIRS IN SERIES: ROSEIRES AND SENNAR CASE STUDY". Міжвідомчий тематичний науковий збірник "Меліорація і водне господарство", n.º 2 (23 de dezembro de 2021): 5–23. http://dx.doi.org/10.31073/mivg202102-310.
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The Roseires-Sennar Dams System (RSDS) at lower part of Blue Nile River play a vital role in water supply to the irrigation schemes in Sudan. The existing rule curves for this system belong to 1925 and 1966 for Sennar and Roseires reservoirs, respectively. Introduction of new irrigation schemes, approved climate change impacts on Blue Nile River flow and upstream developments in Ethiopia as well as the heightening of the Roseires Dam from elevation 480 to 490 m.a.s.l have shown the RSDS is losing its efficiency in terms of fully supplying the water demands. The literature addresses the simulation of Roseires and Sennar dams, and tries to find the best coordinated rule curves through a limited number of operation rules to find optimal operating rules for reservoirs that minimize the impacts of new developments, water demand growth and climate change on water supply to various demands on Blue Nile River. Such decisions are locally optimal in best condition since they do not consider the storage and carry-over capability of reservoirs that can transfer the non-optimal (locally optimal) decisions to other time steps of planning horizon and creat shortages in other time steps. Therefore, aim of this research is to find optimal coordinating operation rules for Roseires and Sennar dams that through a non-linear multi-period optimization model that considers the conditions of climate change, flow regime and water demand as scenarios. Model is validated by comparison with observed reservoir operation during November 1999 till May 2000. Eighteen scenarios that cover the normal, dry and very dry flow regimes, along with three suggested crop patterns and climate change impact are analyzed. Results shows in normal conditions of flow, crop pattern 2 is the most recommended with more than 11 Billion USD marginal profit and fully supplying the water demand and 1530 GWh energy generation per annum. The coordinated rule curves have a totally different pattern of emptying and filling compared with existing ones. Rule curves change from one flow regime to another, which proves how change in conditions of the system has influence on optimal operation rules. Comparison of marginal profits with crop pattern 2 shows in three inflow conditions of normal, dry and very dry years multi-period optimization model could keep the marginal profits above 11 Billion USD, let’s say, 11,050, 11,056 and 11,042 Billion USD, respectively, which shows the robustness of model in dealing with all conditions and keeping the marginal profits not affected. However, the Roseires rule curves are different in these three condition, while Sennar rules curves are almost the same. Without climate change impact, model can manage to supply the water demands fully in all flow conditions. However, water supply reliability is affected by climate change with all crop patterns. Roseires-Sennar Dams system in a normal year under climate change can produce 10,688 Billion USD marginal profit and 1371 GWh per year energy. It shows that model could manage the system performance so that climate change decrease the marginal profit by 3.27%, while inflow is reduced by 25% and water demands and evaporation increased by 19%. Energy generation under climate change has decreased by 10.5%, which is the most affected sector. Crop pattern 2 and 3 are not suitable for climate change conditions since up to 65% deficit in water supply can happen if very dry year realizing with climate change. In very dry conditions crop pattern 1 is more suitable to be practiced.
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Smith, Orla M. "Emptying the reservoir". Science 360, n.º 6388 (3 de maio de 2018): 503.4–503. http://dx.doi.org/10.1126/science.360.6388.503-d.
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Flølo, L. H., J. M. Kjærefjord, D. M. Arnesen, W. P. Menard e K. W. Weissenburger. "Revealing the Petrophysical Properties of a Thin-Bedded Rock in a Norwegian Sea Reservoir With Logs, Core, and Miniperm Data". SPE Reservoir Evaluation & Engineering 3, n.º 03 (1 de junho de 2000): 249–55. http://dx.doi.org/10.2118/64273-pa.
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Summary An unconventional thin-bed analysis based on logs, core, and miniperm data was needed to calculate the petrophysical properties of a reservoir under development in the Norwegian Sea. More than half of the reservoir section under investigation is composed of heterolithic facies: thinly interbedded sandstone and mudstone layers from one to several centimeters in thickness and of variable quality. By using miniperm measurements with 1-cm spacing on slabbed core, it was possible to resolve the properties of the rock far below the vertical resolution of conventional wireline logs and relate them to the bulk log measurements. Introduction The Tilje and A°re Formations in the Heidrun Field in the Norwegian Sea are very heterogeneous Jurassic sandstone reservoirs. Rock quality varies from clean, high-porosity, and high-permeability channel sands to low-porosity and low-permeability mudstones. In 1996, a stochastic reservoir simulation study was performed on these formations. This study defined the so-called "marginal facies" as those facies with poor production properties and low recovery.1 The study also estimated that these marginal facies contained about 180 million Sm3 of oil in place. In 1997, a reservoir engineering project was established with the purpose of developing drainage strategies to improve the recovery from the marginal facies. A Marginal Facies Project team was put together to build a new detailed reservoir simulation model, to develop drainage strategies, and to develop well and completion solutions to accommodate the drainage strategy. The team consisted of a geophysicist, petrophysicist, sedimentologist, geomodeler, production geologist, reservoir engineer, production engineer, and a well and completion engineer. The team focused on the bayfill facies, a 50- to 150-m-thick marginal facies of the Åre formation. Cores from Åre bayfills showed the rock to be very heterogeneous with large sections of interbedded sandstone-mudstone laminations down to 1 cm in thickness (Fig. 1). The bayfill facies was neither well described nor well understood with regard to facies architecture, sedimentological features, petrophysical properties, or dynamic properties. The facies architecture and petrophysical properties would strongly influence the dynamic behavior of this reservoir. They would also be critical for improving the estimate of oil in place. To determine an optimum drainage strategy for this kind of reservoir, the reservoir simulation model must have enough detail to accurately reflect the reservoir complexity. Before construction of the simulation model could begin, it was necessary to build up the sedimentological understanding of the bayfill facies, define the conceptual model, rebuild the fine-scale stochastic reservoir model, and eventually upscale and build a detailed simulation model of a selected segment of the reservoir. This paper will concentrate mainly on the petrophysical modeling of the heterogeneous thinly interbedded sandstone-mudstone sequences that constitute a major fraction of the bayfill facies. It will also describe how the petrophysical modeling is connected to the sedimentological understanding and modeling of the bayfill architecture. The Bayfill Facies—Conceptual Model An understanding of the sedimentology and facies architecture of bayfills was built up from well log and core data and from studies of reservoir analogue outcrops (the Campanian Neslen Formation in the Book Cliffs, Utah2). Depositional Environment. As the name implies, bayfills are deposited in marginal marine interdistributary bays, gradually filling with sediments brought by longshore currents from nearby mouthbars and distributary channels/crevasses emptying into the bays. As the bay fills, the shore gradually progrades outward, leaving a relatively thin sheet-like deposit, typically 2 to 8 m thick and 3 to 8 km in diameter. The bayfill sheet is typically coarsening upwards from a mudstone package at the base into a heterolithic package in the middle and a sandstone package at the top (Fig. 2). Down to the depth of the fair weather wave base, the energy level is highest, resulting in sand deposition. Deeper in the bay, where sand is occasionally brought in by storm waves, the energy level is variable and alternating sand and mud are deposited, resulting in a heterolithic lithology. In the deepest parts of the bay, there is no wave influence and mud is deposited. As the bay fills, it is possible for a marsh to form backshore. The marsh vegetation can be transformed into a coal layer. This is often present on top of bayfills. Depositional Environment. As the name implies, bayfills are deposited in marginal marine interdistributary bays, gradually filling with sediments brought by longshore currents from nearby mouthbars and distributary channels/crevasses emptying into the bays. As the bay fills, the shore gradually progrades outward, leaving a relatively thin sheet-like deposit, typically 2 to 8 m thick and 3 to 8 km in diameter. The bayfill sheet is typically coarsening upwards from a mudstone package at the base into a heterolithic package in the middle and a sandstone package at the top (Fig. 2). Down to the depth of the fair weather wave base, the energy level is highest, resulting in sand deposition. Deeper in the bay, where sand is occasionally brought in by storm waves, the energy level is variable and alternating sand and mud are deposited, resulting in a heterolithic lithology. In the deepest parts of the bay, there is no wave influence and mud is deposited. As the bay fills, it is possible for a marsh to form backshore. The marsh vegetation can be transformed into a coal layer. This is often present on top of bayfills.
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Kritsky, Delane, e Masato Nitta. "Dactylogyrids (Platyhelminthes: Monogenoidea) Infecting the Gill Lamellae of Flatheads (Scorpaeniformes: Platycephalidae), with Proposal of Platycephalotrema n. gen. and Descriptions of New Species from Australia and Japan". Diversity 11, n.º 8 (12 de agosto de 2019): 132. http://dx.doi.org/10.3390/d11080132.
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Platycephalotrema n. gen. (Dactylogyridae) is proposed for four new species and 5 previously described species parasitizing the gills of flatheads (Scorpaeniformes: Platycephalidae) as follows: Platycephalotrema ogawai n. sp. (type species) from Platycephalus sp. 1 (type host) and Platycephalus sp. 2, both of Nakabo & Kai (2013) (locally known as “Yoshino-gochi” and “Ma-gochi,” respectively) (Japan); Platycephalotrema austrinum n. sp. from Platycephalus endrachtensis Quoy & Gaimard (type host) and Platycephalus sp. (Australia); Platycephalotrema bassensis (Hughes, 1928) n. comb. from Platycephalus bassensis Cuvier (Australia); Platycephalotrema koppa n. sp. from Platycephalus fuscus Cuvier (Australia); Platycephalotrema macassarensis (Yamaguti, 1963) n. comb. from Platycephalus indicus (Linnaeus) (China, Macassar); Platycephalotrema mastix n. sp. from P. fuscus and P. endrachtensis (Australia); Platycephalotrema platycephali (Yin & Sproston, 1948) n. comb. from P. indicus (China) and P. fuscus (Australia); Platycephalotrema sinensis (Yamaguti, 1963) n. comb. from Cociella punctata (Cuvier) (China); Platycephalotrema thysanophrydis (Yamaguti, 1937) n. comb. from Inegocia japonica (Cuvier), Inegocia ochiaii Imamura, and Cociella crocodilus (Cuvier) (Japan, China). Other species requiring further study but potentially members of Platycephalotrema include Ancyrocephalus vesiculosus Murray, 1931, Haliotrema indicum Tripathi, 1957, Haliotrema swatowensis Yao, Wang, Xia, & Chen, 1998, and Haliotrema pteroisi Paperna, 1972. The primary features differentiating Platycephalotrema include species having: (1) tandem gonads (testis postgermarial); (2) two prostatic reservoirs, each emptying independently into the base of the male copulatory organ; (3) a dextral vaginal pore and large vaginal vestibule; (4) dorsal and ventral pairs of morphologically similar anchors; (5) a ventral bar with spatulate ends; (6) a dorsal bar with bifurcated ends, and (7) absence of an accessory piece. The new species are described, and P. thysanophrydis is redescribed based on newly collected and museum specimens.
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Wu, Chia-Wen, Frederick N. F. Chou e Fong-Zuo Lee. "Minimizing the impact of vacating instream storage of a multi-reservoir system: a trade-off study of water supply and empty flushing". Hydrology and Earth System Sciences 25, n.º 4 (19 de abril de 2021): 2063–87. http://dx.doi.org/10.5194/hess-25-2063-2021.
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Abstract. A reservoir operator does not favor storage above a certain level in situations such as the pre-release operation prior to a flood; scheduled engineering construction; or mechanical excavation of sediment in the impoundments, drawdown, and empty flushing, etc. This paper selects empty flushing as the case study, and a method is presented to promote the feasibility of emptying the reservoir storage. The impact of emptying reservoir on water supply is minimized through appropriate joint operation in a multi-reservoir system, where drawdown and empty flushing is carried out in a primary reservoir, and the other reservoir provides backup water for supply. This method prioritizes allocating the storage in the primary reservoir for water supply during specific periods prior to its emptying. If the storage of every reservoir achieves its predefined conditions, drawdown of the primary reservoir is activated and followed by empty flushing. Previously preserved storage in the other reservoir ensures adequate water supply during the periods of emptying the primary reservoir. Flushing of the primary reservoir is continued until either the accumulative released water exceeds the specified volume, storage in the backup reservoir drops below the predefined threshold, or the inflow to the primary reservoir recedes from the flood peak to be below the releasing capacity of outlets. This behavior is simulated and linked with a nonlinear optimization algorithm to calibrate the optimal parameters defining the activation and termination of empty flushing. The optimized strategy limits the incremental water shortage within the acceptable threshold and maximizes the expected benefits of emptying reservoir.
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Saunders, Steve, Eric Tenor, Joseph Wakawa e John Nohou. "Twenty-Two Years of GPS Monitoring at Rabaul Caldera, a Narrative History". Geosciences 13, n.º 8 (18 de agosto de 2023): 249. http://dx.doi.org/10.3390/geosciences13080249.
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It has long been recognised that volcanoes deform as fluids migrate, or change pressure in fractures and reservoirs within the volcano or in the crust below and around them. Calderas in particular have been shown to deform in complex and often major ways. The Rabaul Caldera is a type example of a caldera that undergoes complex and occasionally rapid deformation. This was first recognised by visual observations, and by the 1970s these movements were being monitored by traditional surveying techniques. Between 1972 and 1994, the centre of the caldera was uplifted by approximately 2 m. Following the 1994 eruption, it was indirectly found that parts of the caldera were uplifted ~6 m in the final hours before the eruption. It was realized that ‘real-time’ monitoring of the uplift may have given a better warning that an eruption was imminent. Traditional surveying techniques are time consuming; in the late 1990s, the only option for real-time monitoring was a Global Positioning System (GPS). By early 2000, a real-time GPS system was working at Rabaul Volcanological Observatory (RVO). Twenty-two years of continually recording differential GPS or Global Navigational Satellite System (GNSS) has proven the technique to be of immense importance. Often it has been the only parameter showing that unrest is happening. At times, inflation and deflation have warned of impending activity or recorded the emptying of the system; at other times, patterns of deformation have been more difficult to interpret. The technique has proven its worth in monitoring the status or general ‘health’ of the caldera, but for more precise forecasts it can only form part of an integrated monitoring system. Current testing of much cheaper receivers and improvements in telemetry mean the technique may soon be available for the more remote volcanoes of Papua New Guinea.
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Ikejder, Youssef, Majda Sebbani, Iliass Hendy, Mounia Khramz, Ali Khatouri e Laila Bendriss. "Impact of Arterial Hypertension on Left Atrial Size and Function". BioMed Research International 2020 (15 de setembro de 2020): 1–7. http://dx.doi.org/10.1155/2020/2587530.
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An increase in left atrial (LA) size in patients with arterial hypertension (AHT) has long been known to be associated with worse cardiovascular morbidity and mortality contributes to various complications, including atrial arrhythmias, stroke, and heart failure. The aim of our study was to evaluate the impact of arterial hypertension (AHT) on the LA size and function. This cross-sectional investigation included one hundred patients with essential hypertension without valvular or structural heart disease and atrial fibrillation. All recruits had a transthoracic echocardiography. LA volumes were measured by area-length method in transthoracic echocardiography at different cardiac cycle times. The indices of LA function were calculated: the reservoir function (total emptying fraction, total emptying volume, and expansion index), the conduit function (passive emptying fraction and passive emptying volume), and the pump function (active emptying fraction and active emptying volume). For all statistical tests, a p value ≤0.05 (represents the degree of significance) is considered statistically significant. In univariate analysis, LA was dilated in 9% of patients. The LA reservoir function and the pump function were increased, respectively, in 85% and 82% of patients. LA conduit function was impaired in 80% of patients. In bivariate analysis, the most powerful factors for this repercussion were diabetes (LA volume MAX dilated in nondiabetic patients (p=0.037)), obesity (the reservoir function was impaired in obese patients (p=0.015)), and antihypertensive drugs (the reservoir function was impaired in patients who take beta blockers (p=0.023); the LA pump function was significantly impaired in patients treated with calcium antagonists (p=0.012)). This study proved the impact of AHT on the LA size and function. Further investigations are necessary to evaluate the potential predictive value of LA remodeling in hypertensive patients like speckle tracking imaging.
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Yannur, Budi, Didit Suprihanto, Happy Nugroho, Aji Ery Burhandenny e Restu Mukti Utomo. "Prototype System Water Level Reservoir untuk Pengendalian Kelebihan Air dengan Mikrokontroller Arduino Uno R3". Edumatic: Jurnal Pendidikan Informatika 5, n.º 2 (20 de dezembro de 2021): 352–61. http://dx.doi.org/10.29408/edumatic.v5i2.4233.
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PDAM Loa Kulu Branch still uses sticks or poles as an indicator of the water level in the reservoir. Reservoir is a place to store clean water production from PDAM, the weakness of using sticks or poles is when the operator does not monitor continuously causing air loss when production becomes large. The goal of the study was to design a water-level prototype to control excess water in the reservoir. The method used is a prototype with the stage of gathering information through interviewing PDAM staff, creating and repairing prototypes and testing prototypes. The test used hardware consisting of Arduino uno r3, ultrasonic sensor hc-sr04, flowmeter sensor yf-s201, 16 x 2 lcd, relay module, buzzer, solenoid valve 12 V_dc, pump 12 V_dc and display measurement results in the visual studio application 2019. Our findings are that the length of reservoir charging with an average input discharge of 3.6 liters / minute is 2.93 minutes. As for the length of emptying the reservoir with an average output discharge of 1.06 liters / minute is 12.10 minutes. The conclusion of this study is that the system can monitor the water level inside the reservoir automatically and know the time needed for the feeling and emptying process of the reservoir.
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Yannur, Budi, Didit Suprihanto, Happy Nugroho, Aji Ery Burhandenny e Restu Mukti Utomo. "Prototype System Water Level Reservoir untuk Pengendalian Kelebihan Air dengan Mikrokontroller Arduino Uno R3". Edumatic: Jurnal Pendidikan Informatika 5, n.º 2 (20 de dezembro de 2021): 352–61. http://dx.doi.org/10.29408/edumatic.v5i2.4223.
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PDAM Loa Kulu Branch still uses sticks or poles as an indicator of the water level in the reservoir. Reservoir is a place to store clean water production from PDAM, the weakness of using sticks or poles is when the operator does not monitor continuously causing air loss when production becomes large. The goal of the study was to design a water-level prototype to control excess water in the reservoir. The method used is a prototype with the stage of gathering information through interviewing PDAM staff, creating and repairing prototypes and testing prototypes. The test used hardware consisting of Arduino uno r3, ultrasonic sensor hc-sr04, flowmeter sensor yf-s201, 16 x 2 lcd, relay module, buzzer, solenoid valve 12 V_dc, pump 12 V_dc and display measurement results in the visual studio application 2019. Our findings are that the length of reservoir charging with an average input discharge of 3.6 liters / minute is 2.93 minutes. As for the length of emptying the reservoir with an average output discharge of 1.06 liters / minute is 12.10 minutes. The conclusion of this study is that the system can monitor the water level inside the reservoir automatically and know the time needed for the feeling and emptying process of the reservoir.
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Steven, Steven, Priyendiswara Agustina Bella, I. G. Oka Sindhu Pribadi e Liong Ju Tjung. "HUBUNGAN RESILIENSI DENGAN ADAPTASI MASYARAKAT TERHADAP BENCANA BANJIR DI TELUK GONG KECAMATAN PENJARINGAN JAKARTA UTARA". Jurnal Sains, Teknologi, Urban, Perancangan, Arsitektur (Stupa) 5, n.º 2 (31 de outubro de 2023): 1827–36. http://dx.doi.org/10.24912/stupa.v5i2.24339.
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Teluk Gong has become an area that is often flooded every year, especially during the rainy season. The intensity of rain is high and accompanied by the inability of drainage channels and reservoirs that should be able to collect rainwater. Floods in Teluk Gong have occurred since 2007 and floods continue every year. Therefore, the author wants to do research on Teluk Gong. The author uses 2 methods, namely the analysis of the characteristics and impacts of flooding and the relationship between resilience and adaptation forms. The research approach that the author uses is a quantitative method and the nature of this research is scientific research which is research conducted based on facts that actually occur in the field and is supported by theoretical studies related to disaster resilience and adaptation theory as a basis for identifying the relationship between resilience and form of adaptation of the Teluk Gong community house, Penjaringan District. The results of the analysis show that the majority of the people of Teluk Gong have a high level of resilience, with a percentage of 53% and as much as 69% of the people of Teluk Gong have adapted by increasing the floors of their houses, emptying part of the first floor of the building, using flood water barriers, and making parks as a water absorbent. Keywords: resilience; adaptation; floods disaster Abstrak Teluk Gong telah menjadi Kawasan yang sering terendam banjir setiap tahunnya, khususnya pada musim hujan. Intensitas hujan yang tinggi dan disertai ketidakmampuan saluran drainase dan waduk yang seharusnya bisa menampung air hujan. Banjir di Teluk Gong sudah terjadi dari tahun 2007 dan setiap tahunnya terus terjadi banjir. Maka dari itu, penulis ingin melakukan penelitian pada Teluk Gong. Penulis menggunakan 2 metode yaitu analisis karakteristik dan dampak banjir dan hubungan resiliensi terhadap bentuk adaptasi. Pendekatan penelitian yang penulis gunakan adalah metode kuantitatif dan sifat penelitian ini adalah penelitian ilmiah yang merupakan penelitian yang dilakukan berdasarkan fakta yang benar-benar terjadi di lapangan dan didukung dengan kajian teori yang bersangkutan dengan resiliensi bencana dan teori adaptasi sebagai bahan landasan untuk menidentifikasi hubungan resiliensi dengan bentuk adaptasi rumah masyarakat Teluk Gong Kecamatan Penjaringan. Hasil analisis menunjukkan bahwa mayoritas masyarakat Teluk Gong memiliki tingkatan resiliensi yang tinggi yaitu dengan persentase sebesar 53% dan sebanyak 69% masyarakat Teluk Gong telah beradaptasi dengan cara meningkatkan lantai rumah, mengosongkan bagian lantai satu bangunan, menggunakan barier penahan air banjir, dan membuat taman sebagai penyerap air.
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Hameed, Hasan, Khaled Abdullah e Raad Irzooki. "Slopes Stability Simulation of the Proposed Makhool Dam Against Earthquake Action". Iraqi Geological Journal 56, n.º 2B (31 de agosto de 2023): 210–23. http://dx.doi.org/10.46717/igj.56.2b.16ms-2023-8-25.
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This study was designed to analyze the stability of the slopes of the proposed Makhool dam under the influence of the highest seismic acceleration experienced by the dam area since (1997-2022), which is 0.29g with a degree of 7.3ML, due to the earthquake that struck most of the cities of Iraq in 2017. Makhool Dam is a zoned earth dam that is proposed to be built on the Tigris River in north Iraq with length of 3670 m. The study was carried out using Geoslope programs, which used the finite element method. The stability of the dam slopes were analyzed under the influence of the earthquake for three cases, the first at the end of construction (the reservoir is empty), and the second at the maximum level of the reservoir (152.15 m), As for the third, in the case of rapid emptying of the reservoir . The results indicate that the seismic safety factors for the upstream and downstream slopes of the dam are stable and correspond to the minimum acceptable safety factors for the Makhool Dam project. With the exception of the case of the earthquake coinciding with the case of the rapid emptying of the reservoir, where critical stability or collapse of some parts of the upstream slope of the dam may occur, and this case is rare.
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Civilini, F., M. K. Savage e J. Townend. "Shear wave velocity changes induced by earthquakes and rainfall at the Rotokawa and Ngatamariki geothermal fields, Taupō Volcanic Zone, New Zealand". Geophysical Journal International 221, n.º 1 (4 de dezembro de 2019): 97–114. http://dx.doi.org/10.1093/gji/ggz547.
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SUMMARY Fluid injection for geothermal production has the potential to produce subsidence and microseismicity that can incur heavy financial cost or hazard. Due to this, novel ways to monitor subsurface deformation to supplement existing methods are highly sought after. We use seismic ambient noise to obtain time-dependent measurements of shear velocity within the geothermal reservoirs of Rotokawa and Ngatamariki, two producing geothermal fields in the Taupō Volcanic Zone located in the central North Island of New Zealand and operated by Mercury Energy. We investigate the relationship between shear wave velocity changes and geothermal injection by selecting time periods at the fields when injection and production volumes were significantly altered: 2009–2010 at Rotokawa, when geothermal injection was quadrupled due to the start-up of a new power station, and 2012–2013 at Ngatamariki, the beginning of geothermal injection for electricity production at that field. Shear wave velocity changes are computed from the ambient noise cross-correlation coda using the Moving Window Cross-Spectral (MWCS) technique, with a reference stack encompassing all data prior to the change in injection rate and moving stacks of 10–50 d. Gradual positive and negative shear velocity changes with a periodicity of approximately 12 months were observed at both sites, with maximum amplitude of 0.06 ± 0.04 and –0.08 ± 0.03 per cent at Rotokawa and 0.07 ± 0.03 and –0.06 ± 0.02 per cent at Ngatamariki. We hypothesize that these changes are due to seasonal rainfall, as seismic velocities computed by ambient noise are sensitive to the filling and emptying of near-surface pore space. In addition to these gradual responses, we found several sharp negative changes in velocity that reach minimum values over a few days and then gradually equilibrate to prior values over a few weeks. The amplitude of these responses is between –0.03 and –0.07 per cent and coincides with regional and local earthquakes. We hypothesize that these responses are primarily produced by the creation of new fractures, the same mechanism that produces gradual groundwater level decreases at regional distances from earthquake epicentres. We analyse a periodic signal within the time-delay measurements and determine that it is at least in part caused by the MWCS window size smoothing the cross-coherence of the ambient seismic signal. We do not observe shear wave velocity changes coinciding with geothermal injection, which may suggest that the signal has lower amplitude compared to the seasonal and seismic responses. We use bandstop filters and polynomial curve fitting to remove the contribution of the seasonal signal, but see no evidence of a shear wave velocity response due to geothermal fluid injection.
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Ravelli, Alberto M., Lewis Spitz e Peter J. Milla. "Gastric Emptying in Children with Gastric Transposition". Journal of Pediatric Gastroenterology and Nutrition 19, n.º 4 (novembro de 1994): 403–9. http://dx.doi.org/10.1002/j.1536-4801.1994.tb11460.x.
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SummaryUsing the noninvasive technique of electrical impedance tomography (EIT), gastric emptying was studied in 12 children, aged 9 months to 17 years, who had undergone gastric transposition (six with pyloroplasty) for oesophageal replacement (seven oesophageal atresia, five severe caustic or peptic damage). In two patients, gastric antral electrical control activity was also studied using surface electrogastrography. Nine patients had problems on oral feeds (respiratory symptoms, feeding difficulties, vomiting, abdominal pain, symptoms suggesting dumping), whilst three were asymptomatic. All 12 patients were tested with a milk meal; in addition four (two with and two without dumping symptoms) were tested with a hypertonic glucose drink; gastric emptying of the milk meal was expressed as the percentage of the meal remaining in the stomach at 60 min (R60). Mean (±2 SD) R60 was 54.6% (±17.4%) in 12 healthy controls and 59.8% (±83.2%) in the 12 patients. Gastric emptying was normal in one patient (R60, 42.6%), delayed in seven (mean R60, 91.2%; range, 74.4–100%), and accelerated in four (R60, 0%). The emptying rate was unrelated to the presence or absence of pyloroplasty. Furthermore, the emptying pattern was extremely irregular, suggesting that gastroesophageal as well as duodenogastric reflux episodes occurred in all patients. The hypertonic glucose drink induced dumping (50% of the meal emptied at 1–3 min) in all four patients, two of whom had delayed emptying of the milk meal, but the gastric antral electrical control activity occurred at the normal frequency of 0.05 Hz. The transposed stomach does not behave as a simple conduit; in most cases it retains its reservoir function. Irrespective of the patient's symptoms, the transposed stomach empties in an abnormal fashion, and the composition of the meal may considerably affect the emptying pattern.
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Tyszczuk, Krzysztof, Grzegorz Domek e Andrzej Kołodziej. "Problems of Removing Loos Biological Material from a Vacuum Accumulator". MATEC Web of Conferences 357 (2022): 02015. http://dx.doi.org/10.1051/matecconf/202235702015.
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Precise fragmentizer RPW17-TN he allows to the crumbling oily materials of biological (flax seeds, white mustard). The ambition of the product of crumbling from the reservoir is the indispensable element of the process. The introduction of pneumatic transportation changes the working arrangement and the fall of the efficiency of the process of crumbling causes, even to the zero –what joins with blocking fragmentizer. The discussion was undertaken in the article over the possible law suits and constructional solutions of the industrial use of emptying the hypotensive reservoir.
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Jamaluddin, Jamaluddin, Nuruddin Kafy El-Ridlo, Hamriani Ryka e Maria Maria. "SIMULASI DISTRIBUSI TEKANAN INJEKSI PADA RESERVOIR MENGGUNAKAN METODE FINITE DIFFERENCE". JURNAL GEOCELEBES 4, n.º 1 (1 de janeiro de 2020): 1. http://dx.doi.org/10.20956/geocelebes.v4i1.7439.
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The modeling of reservoir injection pressure distribution is very important to perceive reservoir management, especially in estimating the pushing mechanism. The modeling of reservoir injection pressure distribution was carried out by applying the analytic equation of fluid flow to the porous media of Darcy's law and transformed to a finite difference numerical equation which then used Neumann boundary conditions. The parameters used in the modeling were: permeability, average layer thickness, porosity, acceleration of gravity, viscosity, and area’s width. Based on the results of modeling, the injection pressure distribution area decreased as injection pressure rate increased. This decrease occurred due to an imbalance between the volume of reservoir fluid produced by the volume of water from the aquifer that replaced the reservoir, caused emptying. From the results of the modeling the amount of oil production, obtained from the remaining oil reserves to the initial oil acquisition in the reservoir after the process of pressure maintenance, could be found.
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N, Karthikrao. "ASSESSMENT OF LEFT ATRIAL FUNCTION IN PATIENTS WITHMITRAL VALVE DISEASES". Asian Journal of Pharmaceutical and Clinical Research 9, n.º 6 (1 de novembro de 2016): 334. http://dx.doi.org/10.22159/ajpcr.2016.v9i6.14677.
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ABSTRACTObjective:To observe and assess left atrial (LA) function by observing the differences in conventional Doppler echo parameters of left ventricular inflow, Left atrial appendage, among patients with mitral valve disease.Methods: Forty three mitral valve disease subjects appearing consecutively for echocardiogram (ECHO) test at the cardiology department in a tertiary care hospital were recruited into the study as per the pre-set inclusion and exclusion criteria. The data from the ECHO was pooled using Microsoft excel and analyzed using SPSS software by application of appropriate statistical tests.Results:Of the 43 objects, 39 had MS, 3 had MR and 2 of them were found to have both MS and MR. The major presenting symptom as observed in 33 subjects, was dyspnea. LA maximum volume was found to be 91±59 ml and minimum was 66±51 ml. Left atrial expansion index was 128±91. Left atrial active emptying fraction was 29±13 and passive emptying fraction was 31±15. No significant change in LA global strain among groups with MR and without MR was observed. Further, no significant difference was observed in left atrial indices like left atrial emptying fraction, left atrial passive emptying fraction, atrial fraction, Left atrial expansion index among groups having MR and no MR.Conclusion:LA contractile, reservoir and conduit function was significantly reduced in mitral valve diseases due to increased hemodynamic load. No significant difference was noted in global LA strain irrespective of MS or MR.Key Words: Valvular disease; Left atria; Strain; Contractile function
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Dhukia, Suman, Asem Rangita Chanu, Sambit Sagar, Jasim Jaleel, Priyanka Gupta, Dikhra Khan, Sivasankar Kanankulam Velliangiri, Bangkim Chandra Khangembam, Chetan Patel e Rakesh Kumar. "Normative Data of Liquid Gastric Emptying and Small-bowel Transit: A Prospective Cross-sectional Study". Indian Journal of Nuclear Medicine 39, n.º 2 (março de 2024): 98–105. http://dx.doi.org/10.4103/ijnm.ijnm_148_23.
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Abstract Purpose of the Study: The primary objective was to establish the reference values for liquid gastric emptying and small bowel. The secondary objectives encompassed comparing the anterior view and geometric mean methods, assessing gender differences, and exploring potential correlations with age. Materials and Methods: Thirty-five consecutive healthy participants (28 females and 7 males) with a mean age of 42 ± 11 years (median, 42; range, 23–65) underwent liquid gastric emptying scintigraphy at five intervals (0, 0.5, 1, 2, and 4 h), with optional additional imaging at 24 h. Liquid gastric emptying was evaluated using percent retention and half-time (T1/2). Small-bowel transit was assessed using the index of small-bowel transit (ISBT), calculated as the ratio of terminal ileal reservoir counts to total abdominal counts at 4 h. Reference values were established based on percentiles or mean and standard deviation (SD). Rapid small-bowel transit was determined through visual inspection. Statistical analysis involved paired Samples t-test or Wilcoxon signed-rank test for comparing imaging methods, independent Samples t-test or Mann–Whitney U-test for gender comparison, and Spearman’s rank correlation for assessing age-related associations. A 2-tailed P < 0.05 indicated significance. Results: Rapid liquid gastric emptying based on the geometric mean method was defined as percent retention <8% at 30 min, while delayed emptying as percent retention >33%, >20%, and >4% at 1, 2, and 4 h, respectively. The reference range of T1/2 of gastric emptying was 10–60 min. The reference value for small-bowel transit using the geometric mean method was established as ISBT >30% at 4 h, while rapid small-bowel transit was defined as the first visualization of activity in the cecum-ascending colon within 1 h. Parameters for liquid gastric emptying and small-bowel transit were notably higher in the anterior view method compared to the geometric mean method (P ≤ 0.019), except for percent retention at 2 h (P = 0.510). Nevertheless, the obtained reference values, whether based on percentiles or mean and SD, showed no notable variance between the two methods to warrant clinical significance. Gender did not display an impact on liquid gastric emptying or small-bowel transit in either method (P ≥ 0.173), and age demonstrated no significant moderate or strong correlations (Spearman’s ρ ≤ 0.397). Conclusion: The study determined reference values for liquid gastric emptying and small-bowel transit through a standard gastric emptying scintigraphy protocol, avoiding additional complex procedures or extended imaging sessions. The established normative data can apply to individuals of both genders aged ≥18 years. While advocating the geometric mean method as the primary choice, the study acknowledges that in busy centers handling multiple studies with limited resources and a single-head gamma camera catering to multiple studies, the anterior view method remains a feasible alternative.
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Williamson, M. E. R., J. C. Boyce, A. S. Miller, W. G. Lewis, D. Johnston e A. H. Smith. "Measurement of pelvic ileal reservoir emptying after restorative proctocolectomy for ulcerative colitis". Nuclear Medicine Communications 16, n.º 4 (abril de 1995): 232. http://dx.doi.org/10.1097/00006231-199504000-00083.
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Heppell, J., P. Belliveau, R. Taillefer, S. Dubé e V. Derbekyan. "Quantitative assessment of pelvic ileal reservoir emptying with a semisolid radionuclide enema". Diseases of the Colon & Rectum 30, n.º 2 (fevereiro de 1987): 81–85. http://dx.doi.org/10.1007/bf02554934.
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Riesenkampff, Eugénie, Lena Mengelkamp, Matthias Mueller, Siegfried Kropf, Hashim Abdul-Khaliq, Samir Sarikouch, Philipp Beerbaum et al. "Integrated analysis of atrioventricular interactions in tetralogy of Fallot". American Journal of Physiology-Heart and Circulatory Physiology 299, n.º 2 (agosto de 2010): H364—H371. http://dx.doi.org/10.1152/ajpheart.00264.2010.
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The atria play an important role in cardiac performance. We evaluated their function and the atrioventricular interaction in operated patients with tetralogy of Fallot (TOF). Twenty patients who had undergone surgical repair of TOF and seven controls were investigated. Patients had residual pulmonary but no major tricuspid valve insufficiency. Atrial and ventricular strain rates were obtained by echocardiographic speckle tracking. Cine MRI-derived volumetric analysis provided atrial and ventricular time volume and time volume change curves yielding emptying and filling parameters. In addition, at the atrial level, reservoir, conduit and pump function, and cyclic volume change were calculated. At the atrioventricular valve level, tricuspid and mitral annular plane systolic excursion (TAPSE and MAPSE, respectively) were measured by two-dimensional echocardiography. In the patients compared with controls, right ventricular end-diastolic volumes were increased and biventricular ejection fraction was decreased (all P < 0.05). Biventricular measures of early diastolic ventricular filling were at control levels, but in late diastole, right ventricular filling parameters and strain rates were decreased ( P < 0.001). The maximal right atrial size was slightly but not significantly diminished, but cyclic volume change was significantly reduced ( P < 0.0001). Pump and reservoir function were decreased ( P < 0.05), and conduit function was elevated ( P < 0.001). The left atrium showed reduced reservoir function and cyclic volume change ( P < 0.05). TAPSE and MAPSE were also decreased ( P < 0.05). There were statistically significant interdependencies between RV ejection fraction, TAPSE, and right atrial filling and emptying parameters (all P < 0.05). In TOF patients, moderate systolic and diastolic right ventricular dysfunction is associated with clearly impaired right atrial function. The left atrium is affected to a lesser extent.
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Milanović, Saša, Ljiljana Vasić, Branislav Petrović, Tina Dašić, Veljko Marinović e Petar Vojnović. "The Impact on Karst Aquifer Regimes Induced by a Surface Reservoir in Karst through Multiparametric Analyses (Reservoir Bileća—Herzegovina)". Sustainability 15, n.º 15 (3 de agosto de 2023): 11968. http://dx.doi.org/10.3390/su151511968.
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The results of long-term groundwater monitoring in the Bileća reservoir adjacent (eastern Herzegovina, Bosnia and Herzegovina) indicate that there is a good hydraulic connection between the reservoir and the karst aquifer located in the right bank of the reservoir. In remote parts of the right-bank karst aquifer, due to complex lithostratigraphic characteristics and a tectonic structure, the influence of the reservoir is very variable and has been insufficiently studied up until now. This paper presents the analysis and synthesis of new, relevant hydrogeological data, as a basis for the creation of a 3D spatial model, i.e., the analysis of the karst system’s behaviour, both under regular and artificial hydrological conditions of surface reservoir construction and its continuous use (filling and emptying). The interactive connection of the model and complex surface and groundwater time series monitoring data of this system is presented through the analysis of its hydrodynamic characteristics, which completes the spatial model of the karst regime caused by low and high groundwater levels and low and high reservoir water levels. The integration of all the data into one model and further multiparametric analyses revealed the different types of hydrodynamic conditions prevailing in the karst aquifer with regard to the influence of the high or low waters of the reservoir.
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Yu, Shou Bing, Kai Rong Wang e Wan Zhan Wang. "Study on Dynamic Equilibrium of Sediment Transport by Qingshuigou Course of the Yellow River". Applied Mechanics and Materials 212-213 (outubro de 2012): 351–57. http://dx.doi.org/10.4028/www.scientific.net/amm.212-213.351.
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The multi-object application of the Xiaolangdi Reservoir and water and sediment regulation have greatly changed flow and sediment conditions emptying into the Yellow River Estuary. By use of flow and sediment field data at the Lijin Hydrological Station and river cross-section elevation data during 2001~2010, the paper has analyzed characteristics of the Yellow River Estuary in terms of incoming flow and sediment conditions, main flume area, average river longitudinal section and river length. The results show that annual total water volume emptying into the Estuary since 2003 has maintained about 200×108 m3, annual total sediment 1.77×108 t, whole annual average sediment concentration 9.3kg/m3, which are stable and beneficial for dynamic equilibrium of sediment transport. Interannual stability of main flume area, average river bed elevation and river length since the Lijin Section during 2007-2010 indicate that current Qingshuigou Course of the Yellow River has achieved dynamic equilibrium of sediment transport.
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Zedan, Adnan Jayed, Marewan Ridha Faris e Ali Kareem Bdaiwi. "Performance Assessment of Shirin Earth Dam in Iraq Under Various Operational Conditions". Tikrit Journal of Engineering Sciences 29, n.º 2 (4 de agosto de 2022): 61–74. http://dx.doi.org/10.25130/tjes.29.2.8.
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Proper dam management should be ensured regularly to avoid breaches and failure. In this study, the finite element method was used to analyse the stability of the Shirin earthen dam under various conditions. The necessary laboratory tests for soils used in the construction of the dam were carried out in the laboratories of the College of the Engineering /University of Tikrit, and these data were employed in the GEO-STUDIO program to analyse the seepage and stability of the dam. The seepage was analysed at three levels of the water lake reservoir including the highest, middle and lowest water levels. In addition, factors such as the permeability of the shell layer, the presence and thickness of the dam’s core layer, the placement of filters at the back of the dam and the exit gradient have been considered. The results have shown that by increasing the permeability of the shell layer, the exit gradient is decreased while the seepage through the dam body is increased. The presence of the dam’s core layer has a significant effect on reducing the amount of seepage through the dam’s body as the amount of seepage is reduced by (99%). Moreover, it was found that the minimum safety factor is 1.95 and it occurs after (4 days) of the rapid emptying of the reservoir, and this indicates that the upstream slope of the dams is safe during water emptying.
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Zherlov, G. K., C. P. Bashirov, I. V. Pankratov e D. G. Chepezubov. "Surgery of «low» rectal cancer — prospects of modern oncoproctology". Bulletin of Siberian Medicine 3, n.º 3 (30 de setembro de 2004): 80–86. http://dx.doi.org/10.20538/1682-0363-2004-3-80-86.
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Use of endoscopic ultrasonography in diagnostics of rectal low-ampullar malignant neoplasms has permitted to the authors to define the list of intersphincteric resection indications consisted in total mesorectumectomy and rectal and interior sphincter resection. The method of spheroidal reservoir formation with artificial unstriped muscular sphincter-cuff has been developed for the prophylaxis of anal incontinence and multimoment emptying after intersphincter resection with the colon bringing down. 14 patients have been operated with survey time up to 3,5 years. According to the data of clinical investigations the spheroidal reservoir form with small initial size and with the ability to extensibility as well as autonomous obturator function of striped muscular sphincter have become the basic conditions for the restoration of continence act and stool frequency in far period after intersphincter resection.
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Williamson, Michael E. R., Jeanetta C. Boyce, Andrew S. Miller, Wyn G. Lewis, Peter M. Sagar, Peter J. Holdsworth, Alan H. Smith e David Johnston. "The effect of pelvic ileal reservoir volume and antiperistaltic reflux on emptying efficiency". Diseases of the Colon & Rectum 43, n.º 10 (outubro de 2000): 1368–74. http://dx.doi.org/10.1007/bf02236632.
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Laub, M., K. Hvid-Jacobsen, P. Hovind, I. L. Kanstrup, N. J. Christensen e S. L. Nielsen. "Spleen emptying and venous hematocrit in humans during exercise". Journal of Applied Physiology 74, n.º 3 (1 de março de 1993): 1024–26. http://dx.doi.org/10.1152/jappl.1993.74.3.1024.
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The spleen may release pooled erythrocytes to the general circulation during strenuous conditions such as heavy exercise. Most of our knowledge of this reservoir function of the spleen derives from animal studies, and the splenic contribution to the circulating blood volume in humans has been regarded as unimportant. We recorded the erythrocyte content in the human spleen during graded bicycle exercise to maximal working capacity. In five normal adults 99mTc-labeled autologous erythrocytes were injected intravenously, and the subjects were placed on bicycles with the back against a gamma camera focusing on the spleen. During increasing exercise the splenic erythrocyte content decreased linearly, and at maximal work load it had been reduced to a mean of 34.2% (range 44–26%) of the initial count rate at supine rest. Concomitantly norepinephrine and epinephrine in plasma increased gradually, whereas neuropeptide Y increased only at maximal exercise. A rise in hematocrit from a mean of 44.6 to 48 was observed, but the autotransfusion of erythrocytes from the spleen only partly explains the rise in hematocrit during physical activity.
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Sareban, Mahdi, David Zügel, Paul Hartveg, Martina Zügel, Thomas Gary, Josef Niebauer, Jürgen Steinacker e Gunnar Treff. "Preserved Left Atrial Mechanics Following a 5-h Laboratory Triathlon in Euhydrated Athletes". International Journal of Sports Medicine 40, n.º 02 (3 de janeiro de 2019): 88–94. http://dx.doi.org/10.1055/a-0750-5780.
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AbstractThe purpose of this study was to investigate echocardiographic changes in left ventricular (LV) diastolic filling and left atrial (LA) strain mechanics following prolonged exercise. Ten male triathletes completed a 60-min swim, 180-min bike exercise, and a 60-min all-out run in a laboratory environment. Special attention was paid to prevent dehydration and energy deficit during the exercise protocol. All participants underwent comprehensive echocardiographic analyses of Doppler- and volumetric-derived LV diastolic filling indices and novel speckle-tracking echocardiography (STE)-derived LA strain indices. LV stroke volume (pre: 108.0±15.9 vs. post: 88.8±19.0 mL; p=0.03) and LA passive emptying volume (pre: 31.2±7.5 vs. post: 22.4±9.8 mL; p=0.05) were significantly reduced following the exercise protocol. Of the STE-derived indices of LA function, reservoir and conduit strain did not change significantly, while there was a trend towards enhanced contraction strain (pre: 15.1±3.8 vs. post: 19.4±4.8%; p=0.07). Resting heart rate was significantly higher post-exercise (53.1±5.0 vs. 81.9±16.9 bpm; p<0.001) and its change correlated strongly with depression of Doppler-derived ratio of early to late ventricular filling velocities (r=0.74, p=0.01) and reduction of LA passive emptying volume (r=0.86, p=0.01). Following prolonged exercise, LV stroke volume was reduced due to heart rate related reduction in LA passive emptying volume whereas global LA strain mechanics were not compromised in this study.
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Fedirko, Volodymyr O., Andrii G. Naboichenko, Mykola V. Iehorov, Albina I. Trеtiakova e Oleksandra Y. Malysheva. "Treatment strategy for the tumor cyst of the medulla in an eloquent area: a case report and review of the literature". Ukrainian Neurosurgical Journal 27, n.º 1 (29 de março de 2021): 51–56. http://dx.doi.org/10.25305/unj.215544.
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This is a clinical case of a 24-year-old woman with the unrescetable cystic tumor of the medulla because of eloquent area involved and severe neurological symptoms caused by the recurrent cystic component. The patient underwent emptying the cyst twice previously by means of safe entry zone myelotomy. Later there was a recurrence of the cyst with a significant neurological and oweral deterioration which is typical for such neoplasms. Recurrent cystic mass-effect was resolved with the help of newly designed device implanted. It provided simultaneous stable cisternal drainage and an opportunity for active aspiration via Ommaya reservoir.
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Ran, Hong, Matthias Schneider, Lin-lin Wan, Jun-yi Ren, Xiao-wu Ma e Ping-yang Zhang. "Four-Dimensional Volume-Strain Expression in Asymptomatic Primary Hypertension Patients Presenting with Subclinical Left Atrium-Ventricle Dysfunction". Cardiology 145, n.º 9 (2020): 578–88. http://dx.doi.org/10.1159/000508887.
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Objective: The purpose of this study was to evaluate the different components of left atrial (LA) dysfunction predictors in asymptomatic primary systemic hypertension patients with preserved left ventricular (LV) ejection fraction, particularly using LA 4-dimensional (4D) longitudinal and circumferential strain values. Methods and Results: Patients with no left ventricular hypertrophy (NLVH) and left ventricular hypertrophy (LVH) are all asymptomatic regarding primary blood hypertension. Thirty NLVH patients and 30 LVH patients according to LV mass index and 40 controls analyzed by 4D echocardiography were prospectively enrolled. LA volumes and longitudinal and circumferential strains were measured using 4D volume-strain echocardiography with a Vivid E95 Version 203 instrument. Correlation analysis indicated a significant relation between LV 4D mass index and LA 4D longitudinal/circumferential strain (r = –0.446 to 0.381, p = 0.000–0.042). LVH patients had a reduced LA emptying fraction compared with NLVH patients and control subjects (p < 0.01). NLVH patients had an impaired LA conduit function and increased contractile function compared with the control group (p < 0.01). LVH patients had increased LA volumes and significantly decreased reservoir, conduit and contractile functions compared with the controls (p < 0.01). LVH patients had increased LA volumes and decreased reservoir and contractile functions compared with NLVH patients (p < 0.01). The clinical utility of LA 4D volume-strain measurement was verified by receiver-operating characteristic curve analysis showing larger net benefits as evaluated with NLVH, LVH and control group comparisons. Interclass correlation coefficients of interobserver and intraobserver assessments in the LV and LA 4D value evaluations were >0.75 and >0.85, respectively. Conclusions: LVH patients showed increased LA volumes and decreased LA emptying fractions. LA reservoir, conduit and contractile functions were significantly impaired in LVH patients. Decreased LA conduit function and increased contractile function were revealed in NLVH patients. LA volumetric and functional analyses with 4D volume-strain echocardiography may facilitate the recognition of subtle LA and LV dysfunctions in asymptomatic systemic hypertension patients.
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Berisha, Gëzim, Gani Bajraktari, Pranvera Ibrahimi, Ibadete Bytyçi, Nehat Rexhepaj, Shpend Elezi e Michael Y. Henein. "Impaired Left Atrial Reservoir Function in Metabolic Syndrome Predicts Symptoms in HFpEF Patients". International Cardiovascular Forum Journal 4 (4 de dezembro de 2015): 37. http://dx.doi.org/10.17987/icfj.v4i0.171.
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<p><strong>Background and Aim.</strong> The Metabolic Syndrome (MetS) has been shown to be independently associated with increased risk for incident heart failure (HF) and coronary artery disease. The aim of this study was to investigate the additional effect of MetS on LA dysfunction in a group of patients with HF and preserved ejection fraction (HFpEF) and its relationship with symptoms.</p><p><strong>Methods. </strong>This study included 194 consecutive patients (age 62 ± 9 years) with stable HFpEF. LV dimensions, ejection fraction (EF), mitral annulus peak systolic excursion (MAPSE), myocardial velocities (s’, e’ and a’), LA dimensions and volumes were measured. Total LA emptying fraction (LA EF) was measured by Simpson rule volumes. Based on the NCEP-ATP III criteria, patients were divided into two groups; MetS (n=95) and non-MetS (n=108) and were compared with 34 age and gender matched controls.</p><p><strong>Results. </strong>Age and gender were not different between patients and control neither between MetS and non-Met. LV dimensions, EF and longitudinal function indices were also not different. The<strong> </strong>MetS patients had higher LV mass index (p=0.038), lower septal and lateral e’ (p=0.003 and p=0.001, respectively) velocities, larger LA minimal volume (p=0.007) and lower LA EF (p<0.001) compared with the non-MetS patients. Age, LA EF and MetS independently predicted the NYHA class.</p><strong>Conclusions. </strong>Despite no difference in LV systolic function, patients with HFpEF and MetS have worse LA emptying fraction, compared with HFpEF and non-MetS patients. In addition, LA reservoir function impairment and MetS independently predict patients limiting symptoms, thus add to a better understanding of HFpEF.
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Sorokin, Yu N. "Neurogenic dysfunction of the lower urinary tract (neurogenic bladder)". Russian neurological journal 26, n.º 5 (12 de novembro de 2021): 61–72. http://dx.doi.org/10.30629/2658-7947-2021-26-5-61-72.
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The lecture presents information about the central and peripheral structures that provide innervation and regulation of the functions of the lower urinary tract — the bladder and urethra. The mechanisms of regulation of the functions of accumulation and retention of urine (reservoir function) and emptying of the bladder (evacuation function) are shown.Neural control of urination is organized in the form of a hierarchical system. The spinal centers are the executive structures, and the cerebral centers are the controlling structures. Involuntary implementation of the act of urination occurs through segmental sympathetic and parasympathetic mechanisms. The regulation of these functions and voluntary urination are carried out by the central mechanisms of the brain — the actuation of the urination reflex is under strict volitional control, which makes it possible to plan the emptying of the bladder in a socially acceptable place and time.The information on the clinical symptoms of neurogenic dysfunction of the lower urinary tract (neurogenic bladder) is reviewed. The features of clinical manifestations depending on the level of damage to neural structures and in various neurological diseases are shown. Methods for assessing urodynamics and treatment directions for neurogenic dysfunction of the lower urinary tract are presented.
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Opp, Christian, Jens Hahn, Nina Zitzer e Gabriela Laufenberg. "Heavy Metal Concentrations in Pores and Surface Waters during the Emptying of a Small Reservoir". Journal of Geoscience and Environment Protection 03, n.º 10 (2015): 66–72. http://dx.doi.org/10.4236/gep.2015.310011.
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Said Abdelkarim, Taher, Mohamed Abd El-Hafez Fouly e Ashraf Zahrah. "Assessment of left atrial function in dilated cardiomyopathy patients using speckle-tracking echocardiography". Egyptian Cardiothoracic Surgeon 2, n.º 1 (1 de janeiro de 2020): 27–32. http://dx.doi.org/10.35810/ects.v2i1.112.
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Background: The available methods to assess left atrial function (LAF) have some limitations as angle dependence and opposite distortion. The objective of the current study was to evaluate LAF in dilated cardiomyopathy (DCM) of ischemic (IDCM) and non-ischemic etiologies (NIDCM) using speckle tracking echocardiography (STE).
Methods: 52 patients with systolic heart failure were included in our study; 27 with IDCM and 25 with NIDCM along with 15 healthy controls. All patients underwent conventional echocardiography, tissue doppler imaging, and speckle tracking echocardiography. The later modality was used to compare left atrial function in IDCM and NIDCM groups.
Results: We found the left atrial maximum volume and the left atrial total emptying volume to be higher in patients with dilated cardiomyopathy compared to healthy patients (52.19 ± 6.01 vs. 21.87 ± 1.69 cm3/m2; p <0.001 and 28.67 ± 4.34 vs. 15.67 ± 2.02 cm3/m2, respectively). Conversely, left atrial emptying index and left atrial active ejection fraction were lower in patients with DCM compared to healthy controls (9.60 ± 2.29 vs. 8.27 ± 3.01 cm3/m2; p< 0.001 and 23 ± 2.56 vs. 37.47 ± 3.54 %; p<0.001, respectively). When comparing the IDCM group with NIDCM patients, we found no significant difference in left atrial maximum volume and left atrial active emptying volume. However, the NIDCM patients had significantly lower left atrial total emptying volume, and left atrial active ejection fraction (8.93 ± 1.86 vs. 9.60 ± 2.29 cm3/m2 and 23 ± 2.56 vs. 31.19 ± 1.66 %; p<0.001). on comparing strain function, DCM patients had lower systolic (28.22 ± 3.84 vs. 60.87 ± 3.07 %, p<0.001), and left atrial systolic strain rate (-2.66 ± 0.45 vs. -3.81 ± 0.35; p = 0.003) compared to healthy controls. All strains and strain rates were significantly lower in NIDCM patients compared to IDCM patients.
Conclusion: STE is a promising method for evaluating LAF in DCM patients. Patients with DCM had significantly lower left atrial systolic and late diastolic strains and strain rates compared to healthy patients. Moreover, NIDCM could be differentiated from IDCM by having more impairment in the LA dynamic reservoir and booster pump function.
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van der Ven, Jelle P. G., Sjoerd S. M. Bossers, Eva van den Bosch, Niels Dam, Irene M. Kuipers, Gabrielle G. van Iperen, Lucia J. M. Kroft, Livia Kapusta, Arend D. J. ten Harkel e Willem A. Helbing. "Dobutamine stress testing for the evaluation of atrial and diastolic ventricular function in Fontan patients". Open Heart 8, n.º 1 (março de 2021): e001487. http://dx.doi.org/10.1136/openhrt-2020-001487.
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ObjectiveTo assess the atrial and ventricular diastolic function response to dobutamine stress in Fontan patients, and to relate these measurements to exercise capacity and events during the follow-up.MethodsWe performed a secondary analysis of a cross-sectional multicentre study of Fontan patients with intra-atrial lateral tunnel (ILT) or extracardiac conduit (ECC) modification. Subjects underwent cardiac MRI during rest and low-dose dobutamine stress, and cardiopulmonary exercise testing. Atrial and diastolic ventricular function parameters were derived from volume-time curves.Medical records were abstracted for a composite end-point of death, listing for transplant, arrhythmia and reintervention. Spearman’s r correlation tests and Cox proportional hazards models were used to assess the relation between the dobutamine response for atrial and diastolic ventricular function and outcomes, including exercise capacity.ResultsWe included 57 patients (26 ECC; 31 ILT) aged 12.8 (IQR (10.3–15.5)) years. During dobutamine stress atrial cyclic volume change increased (3.0 (0.4–5.9) mL/m2, p<0.001), as did early (1.9 (−1.6 to 3.6) mL/m2, p=0.001) and late emptying volume (2.2 (0.2–4.4) mL/m2, p<0.001).Ventricular early filling decreased (−1.6 (−5.7 to 0.7) mL/m2,p=0.046) and ventricular late filling increased (1.0 (−0.4 to 3.4) mL/m2,p<0.001) while stroke volume remained similar.Only for patients with the ECC modification, atrial early emptying volume increase correlated with peak oxygen uptake (ρ=0.66,p=0.002). No other parameter related to exercise capacity.During a median 7.1-year follow-up, 22 patients reached the composite endpoint. No parameter predicted events during the follow-up.ConclusionsDobutamine stress augmented atrial reservoir and pump function for Fontan patients. Atrial early emptying reserve related to exercise capacity in ECC patients. No other atrial or diastolic ventricular function parameter related to outcomes.
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Latuamury, Bokiraiya Okky, Lydia Riekie Parera e Husein Marasabessy. "Characterizing River Baseflow Recession Using Linear Reservoir Model in Alang Watershed, Central Java, Indonesia". Indonesian Journal of Geography 52, n.º 1 (28 de abril de 2020): 15. http://dx.doi.org/10.22146/ijg.43565.
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Alang is a sub-watershed emptying into the Gajah Mungkur Reservoir in Wonogiri, Central Java Indonesia, with an area of 51.01 km2 and lithology composed of Baturetno Formation and Wonosari Formation. Baseflow is a major component of river flow during the dry season. Hence, the characterization of its recession becomes necessary, and it can be performed with innovation in baseflow hydrological modeling, that is, the recession curve. This study was designed to describe the distinctive features of baseflow recession using a linear reservoir model, which is depicted in individual and master recession curves. The baseflow recession in AlangSubwatershed was represented by a combination of varying initial recession discharge (Q0), α, and recession constants (Krb). The individual recession curves were typified by Q0=0.19-9.11, α= 0.089-0.243, and Krb=0.7843-0.9148. As for the master recession curve, it had Q0=9.99, α=0.085, and Krb=0.928. These results signify a sloping recession curve, meaning that the water storage and aquifer characteristics that store and transmit water in Alang Subwatershed are in good condition.
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Camilleri, M., L. J. Colemont, S. F. Phillips, M. L. Brown, G. M. Thomforde, N. Chapman e A. R. Zinsmeister. "Human gastric emptying and colonic filling of solids characterized by a new method". American Journal of Physiology-Gastrointestinal and Liver Physiology 257, n.º 2 (1 de agosto de 1989): G284—G290. http://dx.doi.org/10.1152/ajpgi.1989.257.2.g284.
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Our first aim was to compare 111In-labeled Amberlite IR-12OP resin pellets and 131I-labeled fiber in the assessment of gastric and small bowel transit and colonic filling in healthy humans. Both radiolabels were highly stable for 3 h in an in vitro stomach model and remained predominantly bound to solid phase of stools collected over 5 days [90.5 +/- 2.1 (SE)% for 131I and 87.4 +/- 1.4% for 111In). The lag phase of gastric emptying was shorter for 111In-pellets (30 +/- 11 min compared with 58 +/- 12 min for 131I-fiber, P less than 0.05). However, the slope of the postlag phase of gastric emptying and the half time of small bowel transit were not significantly different for 111In-pellets and 131I-fiber. Filling of the colon was characterized by bolus movements of the radiolabel (10-80% range, 26% mean) followed by plateaus (periods of no movement of isotope into colon lasting 15-120 min, range; 51 min, mean). Half of the bolus movements occurred within 1 h of the intake of a second meal. Thus 111In-labeled Amberlite pellets provide an excellent marker for the study of gastric and small bowel transit and colonic filling in humans. The ileum acts as a reservoir and transfers boluses of variable sizes into the colon, often soon after the intake of a subsequent meal.