51 research outputs found

    Marketing Budget Allocation with Offline Constrained Deep Reinforcement Learning

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    We study the budget allocation problem in online marketing campaigns that utilize previously collected offline data. We first discuss the long-term effect of optimizing marketing budget allocation decisions in the offline setting. To overcome the challenge, we propose a novel game-theoretic offline value-based reinforcement learning method using mixed policies. The proposed method reduces the need to store infinitely many policies in previous methods to only constantly many policies, which achieves nearly optimal policy efficiency, making it practical and favorable for industrial usage. We further show that this method is guaranteed to converge to the optimal policy, which cannot be achieved by previous value-based reinforcement learning methods for marketing budget allocation. Our experiments on a large-scale marketing campaign with tens-of-millions users and more than one billion budget verify the theoretical results and show that the proposed method outperforms various baseline methods. The proposed method has been successfully deployed to serve all the traffic of this marketing campaign.Comment: WSDM 23, Best Paper Candidat

    Prevention of Diabetic Nephropathy by Sulforaphane: Possible Role of Nrf2 Upregulation and Activation

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    The present study was to investigate whether sulforaphane (SFN) can prevent diabetic nephropathy in type 1 diabetic mouse model induced by multiple low-dose streptozotocin. Diabetic and age-matched control mice were given SFN at 0.5 mg/kg body weight daily for 3 months. At the end of 3-month SFN treatment, the diabetic nephropathy, shown by renal inflammation, oxidative damage, fibrosis, and dysfunction, was significantly prevented along with an elevation of renal Nrf2 expression and transcription in diabetes/SFN group compared with diabetic group. However, this renal prevention by SFN was not seen when the 3-month SFN-treated diabetic mice were aged for additional 3 months without further SFN treatment. Nrf2-mediated renal protective effects in diabetes were evaluated in human renal tubular HK11 cells transfected with control and Nrf2 siRNA and treated with 27.5 mM mannitol or high glucose plus palmitate (300 μM). Blockade of Nrf2 expression completely abolished SFN prevention of the profibrotic effect induced by high glucose plus palmitate. These results support that renal Nrf2 expression and its transcription play important roles in SFN prevention of diabetes-induced renal damage. However, the SFN preventive effect on diabetes-induced renal pathogeneses is not sustained, suggesting the requirement of continual use of SFN for its sustained effect

    Spatial analysis of construction land expansion in Suqian during 2007-2017

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    By using Geographic Information System(GIS)spatial analysis tools,the spatial characteristics of construction land expansion within Suqian during 2007-2017 were studied by employing the remote sensing(RS) data of Suqian in 2007,2012 and 2017.The results showed that the construction land in Suqian had entered a stage of rapid growth since 2007.Besides,the spatial expansion intensity of construction land in Sucheng District,Siyang County and Shuyang County had a dominant position.Meanwhile,the spatial difference of expansion intensity of construction land within Suqian was obvious.The strong expansion type and stable type were in the east and west of Suqian respectively between 2007 and 2012.However,the distribution of all kinds of expansion types was decentralized.The severe expansion type mainly distributed in the north,the strong expansion type in the middle,the weak expansion type in the west,and the stable type in the south of Suqian

    Three-dimensional discrete element simulation of the amplification effect of the slope surface under the action of strong earthquakes

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    To study the dynamic amplification effect of slope surfaces under the action of strong earthquakes, a three-dimensional model was established using a rocky slope in Mian County, Shaanxi Province, as an example. The discrete element software 3DEC is used to simulate the deformation and instability process of the slope under dynamic conditions, analyse the dynamic response characteristics of the slope surface, and study the difference in the dynamic response of the slope surface under different seismic wave input conditions. The main conclusions are that when considering the influence of seismic longitudinal waves, the vertical acceleration is significantly enhanced, and the PGA amplification factor of the slope is increased by approximately 1.62 times. The slope shape strongly affects the dynamic response characteristics of the slope surface. Under the action of strong earthquakes, the amplification of the slope shoulder and the slope turning point is very strong, followed by the protruding parts, and the amplification on both sides of the slope surface is the weakest. Under different input conditions, the horizontal PGA amplification factor at the slope turning point maintains a high value, especially when only the horizontal acceleration is input, and this part should be given special attention in the prevention of earthquake landslide disasters. The movement process of a landslide caused by strong earthquakes can be summarized as the initiation stage of the landslide-the high-speed movement stage of the squeeze collision-the accumulation stage. The research results can provide certain theoretical support for disaster prevention and mitigation in this region

    Preventive and Therapeutic Effects of MG132 by Activating Nrf2-ARE Signaling Pathway on Oxidative Stress-Induced Cardiovascular and Renal Injury

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    So far, cardiovascular and renal diseases have brought us not only huge economic burden but also serious society problems. Since effective therapeutic strategies are still limited, to find new methods for the prevention or therapy of these diseases is important. Oxidative stress has been found to play a critical role in the initiation and progression of cardiovascular and renal diseases. In addition, activation of nuclear-factor-E2-related-factor-2- (Nrf2-) antioxidant-responsive element (ARE) signaling pathway protects cells and tissues from oxidative damage. As a proteasomal inhibitor, MG132 was reported to activate Nrf2 expression and function, which was accompanied with significant preventive and/or therapeutic effect on cardiovascular and renal diseases under most conditions; therefore, MG132 seems to be a potentially effective drug to be used in the prevention of oxidative damage. In this paper, we will summarize the information available regarding the effect of MG132 on oxidative stress-induced cardiovascular and renal damage, especially through Nrf2-ARE signaling pathway

    Nuclear medicine radiomics in digestive system tumors: Concept, applications, challenges, and future perspectives

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    Abstract Radiomics aims to develop novel biomarkers and provide relevant deeper subvisual information about pathology, immunophenotype, and tumor microenvironment. It uses automated or semiautomated quantitative analysis of high‐dimensional images to improve characterization, diagnosis, and prognosis. Recent years have seen a rapid increase in radiomics applications in nuclear medicine, leading to some promising research results in digestive system oncology, which have been driven by big data analysis and the development of artificial intelligence. Although radiomics advances one step further toward the non‐invasive precision medical analysis, it is still a step away from clinical application and faces many challenges. This review article summarizes the available literature on digestive system tumors regarding radiomics in nuclear medicine. First, we describe the workflow and steps involved in radiomics analysis. Subsequently, we discuss the progress in clinical application regarding the utilization of radiomics for distinguishing between various diseases and evaluating their prognosis, and demonstrate how radiomics advances this field. Finally, we offer our viewpoint on how the field can progress by addressing the challenges facing clinical implementation

    Carbon Supported Oxide-Rich Pd-Cu Bimetallic Electrocatalysts for Ethanol Electrooxidation in Alkaline Media Enhanced by Cu/CuOx

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    Different proportions of oxide-rich PdCu/C nanoparticle catalysts were prepared by the NaBH4 reduction method, and their compositions were tuned by the molar ratios of the metal precursors. Among them, oxide-rich Pd0.9Cu0.1/C (Pd:Cu = 9:1, metal atomic ratio) exhibits the highest electrocatalytic activity for ethanol oxidation reaction (EOR) in alkaline media. X-ray photoelectron spectroscopy (XPS) and high resolution transmission electron microscopy (HRTEM) confirmed the existence of both Cu and CuOx in the as-prepared Pd0.9Cu0.1/C. About 74% of the Cu atoms are in their oxide form (CuO or Cu2O). Besides the synergistic effect of Cu, CuOx existed in the Pd-Cu bimetallic nanoparticles works as a promoter for the EOR. The decreased Pd 3d electron density disclosed by XPS is ascribed to the formation of CuOx and the spill-over of oxygen-containing species from CuOx to Pd. The low Pd 3d electron density will decrease the adsorption of CH3COads intermediates. As a result, the electrocatalytic activity is enhanced. The onset potential of oxide-rich Pd0.9Cu0.1/C is negative shifted 150 mV compared to Pd/C. The oxide-rich Pd0.9Cu0.1/C also exhibited high stability, which indicated that it is a candidate for the anode of direct ethanol fuel cells (DEFCs)

    A transient production prediction method for tight condensate gas wells with multiphase flow

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    Considering the phase behaviors in condensate gas reservoirs and the oil-gas two-phase linear flow and boundary-dominated flow in the reservoir, a method for predicting the relationship between oil saturation and pressure in the full-path of tight condensate gas well is proposed, and a model for predicting the transient production from tight condensate gas wells with multiphase flow is established. The research indicates that the relationship curve between condensate oil saturation and pressure is crucial for calculating the pseudo-pressure. In the early stage of production or in areas far from the wellbore with high reservoir pressure, the condensate oil saturation can be calculated using early-stage production dynamic data through material balance models. In the late stage of production or in areas close to the wellbore with low reservoir pressure, the condensate oil saturation can be calculated using the data of constant composition expansion test. In the middle stages of production or when reservoir pressure is at an intermediate level, the data obtained from the previous two stages can be interpolated to form a complete full-path relationship curve between oil saturation and pressure. Through simulation and field application, the new method is verified to be reliable and practical. It can be applied for prediction of middle-stage and late-stage production of tight condensate gas wells and assessment of single-well recoverable reserves

    Land Use Change and Ecosystem Health Assessment on Shanghai–Hangzhou Bay, Eastern China

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    Reasonable quantitative assessment on urban ecosystem health is conducive to the sustainable development of the economy and human society. This paper quantitatively evaluated the impact of land use change on ecosystem services and ecosystem health by building a comprehensive evaluation system (vigor–organization–resilience–ecosystem services), and then analyzed the spatial-temporal pattern, evolution characteristics, and driving factors in the Shanghai–Hangzhou Bay area (SHB) over the 2000–2015 period. The results show that: the area of cropland and forest accounted for more than 65% and was mainly converted into built-up land in the past 15 years. The overall ESV showed a trend of first increasing and then decreasing. Forest accounted for the largest proportion of the total ESV, more than 60% in each year. The ecosystem health value of SBH decreased from 2000 to 2015. At the city scale, the ecosystem health was significantly deteriorated. All cities reached the lowest value by 2015. At the districts/counties scale, the number with the relatively well or well level decreased from 32 in 2000 to 20 in 2015 by 24.64% of the total area. Overall, inland regions of SBH had better ecosystem health situation than coastal areas. The rapid urbanization of population and economy were driving factors for the decline of the ecosystem health. The indicator system of integrating the vigor, organization, resilience, and ecosystem service for ecosystem health assessment is a potential method which could provide a quantitative and comprehensive way for evaluating ecological and environmental effects in the future
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