Downstream Control Research Articles

The evolution and disappearance of “false delta” multi-channel systems in postglacial areas (Central Europe)

Abstract River deltas are complex aggradational systems preserving the history of their evolution in the depositional record. While coastal deltas are extensively studied, little is known about “false delta”, multi-channel systems situated at a certain distance from the sea. The term “false delta” is used here in reference to a system of bifurcating alluvial channels influenced by sea level changes, and variations in discharge and sediment delivery. These interactions resulted in the formation of a multitude of channel planforms, and a “delta-like” fluvial landscape. We present the first study that aims to determine the influence of downstream controls (sea level changes) and upstream controls (discharge and sediment delivery) on the evolution of a “false delta” multi-channel system in the postglacial areas of central Europe. Our study is based on geophysical, geological and remote sensing methods, alongside radiocarbon dating (AMS–accelerator mass spectrometry). We use the example of a “delta-like” system of palaeochannels that connected the Obra and Odra Rivers (central Europe, Poland). The “false delta” formed within an ice-marginal valley by the activity of large-scale meandering channels in the Late Glacial period. Between 13,300 and 11,200 cal. BP, a transition to an anabranching and sinuous planform was caused by the coupled effects of a lowering Baltic Sea level, an increase in flood frequency and in sediment delivery. During this period, bifurcation began conveying 30% of the flow through a former subglacial tunnel to the Warta River. The Holocene evolution of this multi-channel system was driven by the interplay of successive sea level rise and sediment delivery from the middle Obra valley, and former subglacial tunnels. The upstream controls dominated during the last 4400 cal. BP, and were enhanced by mill constructions and deforestation in the last millennium. The false delta “disappeared” in the 18th century owing to a 63% decrease in flows. Based on these findings, we propose a model describing the evolution of “false delta” river systems in postglacial areas of Europe. Three stages of evolution are identified: i) formation by high flows, ii) sustaining the flow through particular branches in conditions of dominating deposition, and iii) discontinuation of the false deltas by hydro technical works. The model can be extrapolated to other areas in postglacial Europe and North America after refinement by further field studies.

Analysis of reservoir flood control risk considering forecast uncertainty

The reservoir flood control risk is closely related to the accuracy of hydrological forecasting. High-accuracy hydrological forecasting technology can greatly reduce the reservoir flood control risk. Based on the definition of reservoir flood control risk, the risk exceeding the check water level of the reservoir and the risk exceeding safe flow of downstream flood control object are selected as the risk index of reservoir flood control in this paper. The relationship between the standard deviation of the relative error and the certainty coefficient of the flood process is analyzed. According to the distribution law of the flood forecast error, the Monte Carlo method is used to generate multiple inflow scenarios to simulate the flood control operation of reservoirs and analyze the risk rate of reservoir flood control operation. Taking Xiluodu and Xiangjiaba cascade reservoirs as an example, the risk rate of exceeding the check water level of the reservoir and exceeding safe flow of downstream flood control object under different flood forecasting accuracy are calculated. It provides a scientific basis for flood forecasting and operation of Xiluodu and Xiangjiaba cascade reservoirs.

How does the downstream boundary affect avulsion dynamics in a laboratory bifurcation?

Abstract. Bifurcations play a major role in the evolution of landscapes by controlling how fluxes such as water and sediment are partitioned in distributary and multithread channel networks. In this paper, we present the first experimental investigation on the effect of the downstream boundary on bifurcations. Our experiments in a fixed-wall Y-shaped flume consist of three phases: progradation, transitional, and bypass; the first two phases are net depositional, whereas during the third the sediment flux exiting the downstream boundary matches the input on average. We find that deposition qualitatively changes bifurcation dynamics; we observe frequent switching in the discharge partitioning under net depositional conditions, whereas bypass results in long periods of time where one branch captures most of the flow. We compare our results with a previously developed model for the effect of deposition on bifurcation dynamics. The switching dynamics we observe are more irregular and complex than those predicted by the model. Furthermore, while we observe long periods of time where one branch dominates under bypass conditions, these are not permanent, unlike in the model. We propose that the range of switching timescales we observe arises from a complex interplay of downstream-controlled avulsion and the effect of bars in the upstream channel, including previously unrecognized long-term dynamics associated with a steady bar. Finally, we describe bifurcation experiments conducted with sand but no water. These experiments share the essential feedbacks of our fluvial bifurcation experiments, but do not include bars. In these experiments, we find that the sandpile grows symmetrically while it progrades, but bypass leads to one branch permanently capturing all avalanches. We conclude that the downstream control of deposition vs. bypass is likely a major influence on bifurcation dynamics across a range of physical systems, from river deltas to talus slopes.

Influence of Pipeline Operating Pressure on Value Setting of Automatic Control Valves at Different Pressure Drop Rates

When a natural gas pipeline ruptures, the adjacent upstream and downstream automatic control valves (ACV) should close quickly to prevent leakage or explosion. The differential pressure set point (DPS) at each valve location is the main criteria for value setting in ACV actions. If the DPS is not properly adjusted, the ACV may mistakenly close or it may not take any actions at a proper time. In this study, the effect of characteristic parameters such as pipeline operational pressure (POP) and pipeline pressure drop rate (ROD) due to rupture or a major leak was experimentally investigated on DPS. 25 different conditions with the double set of the mentioned typical characteristic parameters were chosen. In each condition, the differential pressure (DP) was measured over a period of 180 s by statistically analyzing the experimental results, so 25 maximum DP values (DPSs) were obtained. The DPS rises by an increase in ROD or a decrease in POP. Because of using nitrogen gas instead of natural gas for safety reasons and the uncertainties, the DPS results can be practically applied by adding a safety factor of 15%. Finally, the diagram of DPS with respect to ROD and that of non-dimensional DPS (DOP) versus non-dimensional ROD (RTP) were provided for different POP’s.

RIG-I-like receptors direct inflammatory macrophage polarization against West Nile virus infection

RIG-I-Like Receptors (RLRs) RIG-I, MDA5, and LGP2, are vital pathogen recognition receptors in the defense against RNA viruses. West Nile Virus (WNV) infections continue to grow in the US. Here, we use a systems biology approach to define the contributions of each RLR in the innate immune response to WNV. Genome-wide RNAseq and bioinformatics analyses of macrophages from mice lacking either RLR reveal that the RLRs drive distinct immune gene activation and response polarization to mediate an M1/inflammatory signature while suppressing the M2/wound healing phenotype. While LGP2 functions to modulate inflammatory signaling, RIG-I and MDA5 together are essential for M1 macrophage polarization in vivo and the control of WNV infection through potential downstream control of ATF4 and SMAD4 to regulate target gene expression for cell polarization. These analyses reveal the RLR-driven signature of macrophage polarization, innate immune protection, and immune programming against WNV infection.

Monarch butterflies use an environmentally sensitive, internal timer to control overwintering dynamics.

The monarch butterfly (Danaus plexippus) complements its iconic migration with diapause, a hormonally controlled developmental programme that contributes to winter survival at overwintering sites. Although timing is a critical adaptive feature of diapause, how environmental cues are integrated with genetically-determined physiological mechanisms to time diapause development, particularly termination, is not well understood. In a design that subjected western North American monarchs to different environmental chamber conditions over time, we modularized constituent components of an environmentally-controlled, internal diapause termination timer. Using comparative transcriptomics, we identified molecular controllers of these specific diapause termination components. Calcium signalling mediated environmental sensitivity of the diapause timer, and we speculate that it is a key integrator of environmental condition (cold temperature) with downstream hormonal control of diapause. Juvenile hormone (JH) signalling changed spontaneously in diapause-inducing conditions, capacitating response to future environmental condition. Although JH is a major target of the internal timer, it is not itself the timer. Epigenetic mechanisms are implicated to be the proximate timing mechanism. Ecdysteroid, JH, and insulin/insulin-like peptide signalling are major targets of the diapause programme used to control response to permissive environmental conditions. Understanding the environmental and physiological mechanisms of diapause termination sheds light on fundamental properties of biological timing, and also helps inform expectations for how monarch populations may respond to future climate change.

Ecological flow considered multi-objective storage energy operation chart optimization of large-scale mixed reservoirs

A reservoir operation chart is effective in guiding the actual operation of reservoirs. With the development and construction of large-scale mixed reservoirs, operating reservoirs using multiple objective operations has become a hot issue. This study, therefore, improved and expanded the traditional energy storage operation chart (ESOC) model for pure cascade reservoirs based to the special relationships between hydraulics and water volume of the upstream and downstream reservoirs in a mixed reservoir system. Considering the objectives of flood control, energy generation (including power generation, guaranteed output, and assurance rate), and ecological flow, a multi-objective ESOC optimization model for large-scale mixed reservoirs is established, and the corresponding solving method for this model is proposed. Taking the Pearl river basin of China as an example, the multi-objective Pareto fronts of different minimum discharges of upstream reservoirs are obtained. According to the actual operation demands and constraints, the optimal multi-objective schemes under different assurance rates and different ecological flow satisfaction rates are extracted based on the obtained Pareto fronts. For example, if the assurance rate of power generation is required to be equal to or greater than 90% and the ecological flow, the satisfaction rate of downstream control sections is required to be equal to or greater than 0.97, the scheme is the best when the minimum discharge of upstream reservoirs is 300 m3/s, and the corresponding power generation and guaranteed output are 58.989 × 108 kWh and 439 GW, respectively. On the whole, the proposed models and related results have significance for the actual operation of large-scale mixed reservoirs.

Control of oblique-type breakdown in a supersonic boundary layer employing streaks

The effectiveness of streak modes in controlling the oblique-type breakdown in a supersonic boundary-layer at Mach 2.0 is investigated using direct numerical simulations. Investigations in the literature have shown the effectiveness of streak modes in delaying the onset of transition dominated by two-dimensional waves, but in oblique breakdown, three-dimensional waves and a strong streak mode dominate the transition process. Paredes et al. (J. Fluid Mech., vol. 831, 2017, pp. 524–553) discussed the possible stabilization of supersonic boundary layers by optimally growing streaks using parabolized stability equations. However, no study has as yet been reported regarding direct nonlinear control of oblique breakdown. This study deals with the effects of large-amplitude decaying streak modes generated by a blowing–suction strip at the wall to control full breakdown in a reference case. Modes with four to five times the fundamental wavenumber are found to be beneficial for controlling the transition. In the first region after the control-mode forcing, the beneficial mean-flow distortion (MFD), generated by inducing the control mode, is solely responsible for hampering the growth of the fundamental-mode. On the whole, the MFD and the three-dimensional part of the control contribute equally towards controlling the oblique breakdown. The results show significant suppression of transition, and substantial improvements have been observed in the levels of the skin-friction coefficient and wall-temperature in comparison to the uncontrolled case. Moreover, refreshing the control using an additional downstream control strip increases the gain. However, the forcing amplitude must be carefully chosen in order not to introduce a generalized inflection point in the spanwise averaged mean flow invoking enhanced disturbance growth.

Morphodynamic evolution in a meandering reach of the Middle Yangtze River under upstream and downstream controls

Morphodynamic evolution in an alluvial river is usually controlled by various boundary conditions. During the past nearly 50 years, remarkable morphodynamic evolution occurred in the Jianli reach of the Middle Yangtze River owing to the combined effects of an artificial cutoff, the upstream operation of the Three Gorges Project (TGP), and the downstream confluence of the Dongting Lake. To better understand the characteristics of morphodynamic changes in the whole study reach, variations in thalweg shifting and bankfull channel geometry were quantified using a reach-averaged approach, and the effects of upstream and downstream controls were investigated on channel geometry adjustments. Calculated results indicate that: (i) events of an artificial cutoff and high flows caused the average rate of reach-scale thalweg migration to be greater than 35 m/yr, but there was a 22% reduction in the mean migration rate after the TGP operation; (ii) channel geometry adjusted mostly in the aspect of bankfull depth under various river regulation engineering, with the reach-scale bankfull depth increasing by 0.95 m from 2002 to 2016; (iii) the reach-scale bankfull dimensions are closely associated with these accumulated effects of both the altered flow-sediment regime because of upstream dam construction, and the local base-level variation owing to the downstream confluence of the Dongting Lake. Furthermore, these bankfull variables were expressed by power functions of two key parameters, covering the previous five-year average fluvial erosion intensity during flood seasons at Jianli (upstream control), and the corresponding water level difference between Jianli and Lianhuatang (downstream control). The proposed relations were calibrated by the observed data in 2002–2014, and were further verified by measurements in 2015–2016. The proposed methodology can also be applicable to estimate channel geometry adjustments of other similar alluvial rivers controlled by both upstream and downstream boundary conditions.

Banshee distribution network benchmark and prototyping platform for hardware‐in‐the‐loop integration of microgrid and device controllers

This article provides a unique benchmark to integrate and systematically evaluate advanced functionalities of microgrid and downstream device controllers. The article describes Banshee, a real-life power distribution network. It also details a real-time controller hardware-in-the-loop (HIL) prototyping platform to test the responses of the controllers and verify decision-making algorithms. The benchmark aims to address power industry needs for a common basis to integrate and evaluate controllers for the overall microgrid, distributed energy resources (DERs), and protective devices. The test platform will accelerate microgrid deployment, enable standard compliance verification, and further develop and test controllers' functionalities. These contributions will facilitate safe and economical demonstrations of the state-of-the-possible while verifying minimal impact to existing electrical infrastructure. All aspects of the benchmark and platform development including models, configuration files, and documentation are publicly available via the electric power HIL controls collaborative (EPHCC).

EnsembleCNV: an ensemble machine learning algorithm to identify and genotype copy number variation using SNP array data.

The associations between diseases/traits and copy number variants (CNVs) have not been systematically investigated in genome-wide association studies (GWASs), primarily due to a lack of robust and accurate tools for CNV genotyping. Herein, we propose a novel ensemble learning framework, ensembleCNV, to detect and genotype CNVs using single nucleotide polymorphism (SNP) array data. EnsembleCNV (a) identifies and eliminates batch effects at raw data level; (b) assembles individual CNV calls into CNV regions (CNVRs) from multiple existing callers with complementary strengths by a heuristic algorithm; (c) re-genotypes each CNVR with local likelihood model adjusted by global information across multiple CNVRs; (d) refines CNVR boundaries by local correlation structure in copy number intensities; (e) provides direct CNV genotyping accompanied with confidence score, directly accessible for downstream quality control and association analysis. Benchmarked on two large datasets, ensembleCNV outperformed competing methods and achieved a high call rate (93.3%) and reproducibility (98.6%), while concurrently achieving high sensitivity by capturing 85% of common CNVs documented in the 1000 Genomes Project. Given this CNV call rate and accuracy, which are comparable to SNP genotyping, we suggest ensembleCNV holds significant promise for performing genome-wide CNV association studies and investigating how CNVs predispose to human diseases.

Advanced Hydroinformatic Tools for Modelling of Reservoirs Operation

Reservoirs are used to control water flows through downstream waterways: downstream water supply, irrigation, flood control, canals and recreation for hydroelectricity generation. Operation policy is essential for reservoir operation because the impact of the operation on the environment, society and economy is significant. In the context of climate change, special attention should be paid to the following functions of reservoirs: flood control through retain water during high rainfall events to prevent or reduce downstream flooding - in this case the reservoir should be as empty in order to retain a larger volume of water from precipitation and runoff; water supply and irrigation, especially in periods of drought - in this case the reservoir should be as full in order to ensure the necessary volumes of water. A special attention should be given to electricity generation; a reservoir built for hydroelectricity generation can reduce the net production of greenhouse gases when compared to other sources of energy. Therefore, developments of reservoirs operating regulations are very important. The advanced hydroinformatic help to develop these regulations for different scenarios of dangerous hydrological phenomena: heavy and abundant rainfall; rapid snowmelt and drought. Such a tool is MIKE HYDRO Basin software, developed by DHI – Institute for Water and Environment. MIKE HYDRO Basin is a multi-purpose, map-centric decision support tool for integrated river basin analysis, planning and management. This paper contains also a case study: modelling of operation of three reservoirs (Gozna, Valiug and Secu) located in Superior Barzava hydrographic basin.

Development of River Rating Curves for Simple to Complex Hydraulic Structure Based on Calibrated HEC-RAS Hydraulic Model, in Kwale, Coastal Kenya

Accurate and reliable river flow information is critical to planning and management for sustainable water resources utilization. Most of engineering activities related to hydrologic designs, flood, drought, reservoirs and their operations are heavily dependent on the river flow information derived from river rating curve. The rating curve for a given river section is normally developed from a set of direct stage-discharge measurements for different periods. This involves considerable labour, risk and resources, and presupposes a complex and extensive measuring survey. Extrapolating the rating curve beyond the measured range, as common in many cases, is fraught with errors and uncertainties, due to the complex hydraulic behaviour of the surface water profile in transition from section, channel, downstream and flood plain controls which are often poorly understood with direct measurements. Hydraulic modeling has recently emerged as one of the more promising methods to efficiently develop accurate rating curves for a river section with simple or complex hydraulic structures and conditions. This paper explores the use of a Hydraulic Engineering Center-River Analysis System (HEC-RAS) model to review and develop river rating curves for three hydrometric stations on two rivers in Kwale, coastal Kenya. The HEC-RAS models were set up based on topographical (cross section and longitudinal) survey data for the reaches and engineering drawings for the hydraulic structures commonly used as section controls for flow measurement. The model was calibrated under unsteady state conditions against measured stage-discharge data which were captured using a Velocity Current Meter (Valeport) and an Acoustic Doppler Current Profiler (ADCP) for both low and high flow. The rating curves were extracted from model results and the uncertainty associated with each rating curve analyzed. The results obtained by the HEC-RAS model were satisfactory and deemed acceptable for predicting discharge across the stage range at each river section.

Double Closed-Loop Controller Design for Boost Pressure Control of Turbocharged Gasoline Engines

The precise boost pressure control is the key to guaranteeing reliable turbocharged gasoline engine operation. The closed-loop control requires fast boost pressure tracking performance in wide engine operating range. This paper presents a double closed-loop nonlinear control scheme to improve transient tracking performance. The air-path system of the turbocharged gasoline engine is described by a physics-based, nonlinear, mean value model that presents a long regulation channel from the control input, wastegate-opening, to the control output, boost pressure and brings challenges for the controller design with satisfied tracking performance. To address this problem, the outer loop treats the turbine speed as a downstream control demand and adjusts it by using a feedforward-feedback control to achieve fast boost pressure tracking. Subsequently, a disturbance-observer-based nonlinear inner-loop controller is designed to regulate the wastegate that stabilizes the turbine speed tracking error while handles the uncertainties due to operating variation. The stability of the whole closed-loop system is analyzed by the Lyapunov stability theory and the robustness against operating variation is discussed based on input to state stability (ISS). The effectiveness of the proposed controller is validated through a higher fidelity model in AMESim and its performances are compared with well-tuned baseline controllers.

The Cascade Reservoirs Multi-Objective Ecological Operation Optimization Considering Different Ecological Flow Demand

In order to coordinate the power generation and downstream ecological protection benefits,the optimal ecological scheduling of cascade reservoirs is pivotal. In current paper, an improved chaotic normal cloud shuffling frog leaping algorithm (CNSFLA) based on chaotic initialization, cloud model evolution strategy and heuristic frog activation mechanism is proposed to overcome defects of conventional SFLA. Moreover, the multi-objective ecological scheduling model for Qingjiang cascade reservoirs is established with consideration of basic, suitable and ideal ecological flow requirements in Geheyan and Gaobazhou control sections. Afterwards, the model established is applied to cascade reservoirs ecological scheduling in Qingjiang. The water level corridor and penalty function are used to handle constraints. The scheduling results for long series indicate that benefits of power generation and basic ecology flow requirement in downstream control sections are fulfilled completely. While for suitable and ideal ecology flow requirements, 98.33%, 99.17 and 86.33%, 88.17% guarantee rate corresponding to Geheyan and Gaobazhou control sections can be achieved during whole scheduling periods. In terms of typical dry year, the less inflow makes it hard to reach the ideal ecology flow requirement in control sections during several periods even though the scheduling by CNSFLA. The guarantee rates and mean monthly ecological flow shortage are 66.67%, 66.67% and 71, 36 m3/s, respectively. Finally, performance analysis of CNSFLA verifies its effective search ability with high quality & stability results. The cascade power generation obtained by CNSFLA in long series scheduling is 75.45(108 kW·h), corresponding guarantee rates of ideal ecological flow requirement are 86.33 and 88.17%.

Hierarchical Flood Operation Rules Optimization Using Multi-Objective Cultured Evolutionary Algorithm Based on Decomposition

The operation of a reservoir system for flood resources utilization is a complex problem as it involves many variables, a large number of constraints and multiple objectives. In this paper, a new algorithm named multi-objective cultured evolutionary algorithm based on decomposition (MOCEA/D) is proposed for optimizing the hierarchical flood operation rules (HFORs) with four objectives: upstream flood control, downstream flood control, power generation and navigation. The performance of MOCEA/D is validated through some well-known benchmark problems. On achieving satisfactory performance, MOCEA/D is applied to a case study of HFORs optimization for Three Gorges Project (TGP). The experimental results show that MOCEA/D obtains a uniform non-dominated schemes set. The optimized HFORs can improve the power generation and navigation rate as much as possible under the premise of ensuring flood control safety for small and medium floods (smaller than 1% frequency flood). The obtained results show that MOCEA/D can be a viable alternative for generating multi-objective HFORs for water resources planning and management.

Fluid Flow Past a Circular Cylinder with Tandem Rod and Staggered Rod at Low Reynolds Number

The flow past a primary cylinder with one tandem control rod and one staggered control rod is simulated in this paper through solving the Navier-Stokes equations. Two examples are simulated to validate the model, and the results matched well with those of previous researches. The Reynolds number based on the diameter of the primary cylinder is 500. The diameter ratio between the control rod and the primary cylinder (d/D) is 0.25. It was found that the effect of the combination of one upstream tandem control rod and one staggered control rod on the hydrodynamics of the primary cylinder is a linear superposition of the effect of a corresponding single control rod, and the effect of the upstream tandem control rod is dominant at larger spacing ratios such as G/D = 2. For the combination of a downstream tandem control rod and a staggered control rod, the effect of the control rods is different from that of the corresponding single control rod in the region of 0.2<G/D<0.5 & 30°<α<120° and 0.9<G/D<1.4 & 30°<α<50°, where the additional effect is obvious. In this case, the effect of the downstream tandem control rod is dominant at small spacing ratios (such as G/D = 0.1). At moderate spacing ratios such as G/D = 0.4, the effects of the tandem control rod and the staggered control rod are comparable in both cases.

Multi-angle light scattering as a process analytical technology measuring real-time molecular weight for downstream process control

ABSTRACTFor many protein therapeutics including monoclonal antibodies, aggregate removal process can be complex and challenging. We evaluated two different process analytical technology (PAT) applications that couple a purification unit performing preparative hydrophobic interaction chromatography (HIC) to a multi-angle light scattering (MALS) system. Using first principle measurements, the MALS detector calculates weight-average molar mass, Mw and can control aggregate levels in purification. The first application uses an in-line MALS to send start/stop fractionation trigger signals directly to the purification unit when preset Mw criteria are met or unmet. This occurs in real-time and eliminates the need for analysis after purification. The second application uses on-line ultra-high performance size-exclusion liquid chromatography to sample from the purification stream, separating the mAb species and confirming their Mw using a µMALS detector. The percent dimer (1.5%) determined by the on-line method is in agreement with the data from the in-line application (Mw increase of approximately 2750 Da). The novel HIC-MALS systems demonstrated here can be used as a powerful tool for real-time aggregate monitoring and control during biologics purification enabling future real time release of biotherapeutics.

EZH2 Methyltransferase Activity Controls Pten Expression and mTOR Signaling during Fear Memory Reconsolidation.

Memory retrieval induces a transient period of increased transcriptional and translational regulation in neurons called reconsolidation, which is regulated by the protein kinase B (AKT)-mammalian target of rapamycin (mTOR) pathway. However, it is currently unknown how activation of the AKT-mTOR pathway is regulated during the reconsolidation process. Here, we found that in male rats retrieval of a contextual fear memory transiently increased Enhancer of Zeste Homolog 2 (EZH2) levels along with increased histone H3 lysine 27 trimethylation (H3K27me3) levels, which correlated with decreased levels of phosphatase and tensin homolog (PTEN), a potent inhibitor of AKT-mTOR-dependent signaling in the hippocampus. Further experiments found increased H3K27me3 levels and DNA methylation across the Pten promoter and coding regions, indicating transcriptional silencing of the Pten gene. Pten H3K27me3 levels did not change following training or after the retrieval of a remote (old) fear memory, suggesting that this mechanism of Pten repression was specific to the reconsolidation of a new memory. In vivo siRNA-mediated knockdown of Ezh2 in the hippocampus abolished retrieval-induced increases in H3K27me3 and prevented decreases in PTEN levels. Ezh2 knockdown attenuated increases in the phosphorylation of AKT and mTOR following retrieval, which could be restored by simultaneously reducing Pten, suggesting that H3K27me3 regulates AKT-mTOR phosphorylation via repression of Pten Consistent with these results, knockdown of Ezh2 in area CA1 before retrieval impaired memory on later tests. Collectively, these results suggest that EZH2-mediated H3K27me3 plays a critical role in the repression of Pten transcription necessary for AKT-mTOR activation and memory reconsolidation following retrieval.SIGNIFICANCE STATEMENT Understanding how critical translation pathways, like mTOR-mediated protein synthesis, are regulated during the memory storage process is necessary for improving memory impairments. This study tests whether mTOR activation is coupled to epigenetic mechanisms in the hippocampus following the retrieval of a contextual fear memory. Specifically, this study evaluates the role of epigenetic modifications in the form of histone methylation in downstream mTOR translational control during learning-dependent synaptic plasticity in neurons. Considering the broad implications of transcriptional and translational mechanisms in synaptic plasticity, psychiatric, and neurological and neurodegenerative disorders, these data are of interest to the neuroscience community due to the robust and specific regulation of mTOR signaling we found to be dependent on repressive histone methylation.

Integrated Simulation of Spillway and Diversion Structure in Flood Risk Assessment of Upper Solo River

Wonogiri Reservoir is a multi-purpose hydraulic structure that is used for water supply service and flood control in the watershed area of Upper Solo River. Inflow of the Wonogiri Reservoir comes from 10 rivers in the watershed’s catchment area. As for the purpose of reservoir’s sediment controller, a new spillway is constructed; and also closure dike is being built, which influenced the change on reservoir storage characteristic, and then means that a new reservoir operation guideline is necessary. Therefore, study on flood routing on the watershed of Upper Solo River at the new condition of the reservoir operation is needed. The analysis was conducted to acquire detailed information on flood characteristics of Wonogiri Reservoir and Upper Solo River started from the downstream of the reservoir until the downstream control point in the Jurug Water Level Recorder including the flood discharge and the maximum water level. The analysis procedure was performed by four components, which are flood forecasting, reservoir flood routing, rainfall-runoff lateral inflow, and hydraulic channel routing. The analysis result was integrated into a software package which was arranged by using the Microsoft Visual Studio Express 2012, Microsoft Access, and HEC-RAS. With the support of the software, it was expected that the decision making in the spillway operational is more quickly and more accurate (rapid assessment) in order to improve the flood control performance in the area of Upper Solo River.