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81.
The development of cancer is a multifactorial phenomenon, while it constitutes a major global health problem. Viruses are an important factor that is involved in tumorigenesis and is associated with 12.1% of all cancer cases. Major examples of oncogenic viruses which are closely associated with the digestive system are HBV, HCV, EBV, HPV, JCV, and CMV. EBV, HPV, JCV, and CMV directly cause oncogenesis by expressing oncogenic proteins that are encoded in their genome. In contrast, HBV and HCV are correlated indirectly with carcinogenesis by causing chronic inflammation in the infected organs. In addition, the tumor microenvironment contains various immune cells, endothelial cells, and fibroblasts, as well as several growth factors, cytokines, and other tumor-secreted molecules that play a key role in tumor growth, progression, and migration, while they are closely interrelated with the virus. The presence of T-regulatory and B-regulatory cells in the tumor microenvironment plays an important role in the anti-tumor immune reaction. The tumor immune microenvironments differ in each type of cancer and depend on viral infection. The alterations in the immune microenvironment caused by viruses are also reflected in the effectiveness of immunotherapy. The present review aims at shedding light on the association between viruses and digestive system malignancies, the characteristics of the tumor immune microenvironment that develop, and the possible treatments that can be administered.  相似文献   
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We present Stratosphere, an open-source software stack for parallel data analysis. Stratosphere brings together a unique set of features that allow the expressive, easy, and efficient programming of analytical applications at very large scale. Stratosphere’s features include “in situ” data processing, a declarative query language, treatment of user-defined functions as first-class citizens, automatic program parallelization and optimization, support for iterative programs, and a scalable and efficient execution engine. Stratosphere covers a variety of “Big Data” use cases, such as data warehousing, information extraction and integration, data cleansing, graph analysis, and statistical analysis applications. In this paper, we present the overall system architecture design decisions, introduce Stratosphere through example queries, and then dive into the internal workings of the system’s components that relate to extensibility, programming model, optimization, and query execution. We experimentally compare Stratosphere against popular open-source alternatives, and we conclude with a research outlook for the next years.  相似文献   
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ABSTRACT

This paper shows how Markov chain schemes can be used for analyzing equipment availability problems, forecasting the number of dozer engines replacements, studying hoist traffic pattern between various levels in an underground mine and modelling the occurence of good and defective idlers along a conveyor.  相似文献   
86.
This paper proposes a novel method for scheduling and allocating atomic and complex tasks in large-scale networks of homogeneous or heterogeneous cooperative agents. Our method encapsulates the concepts of searching, task allocation and scheduling seamlessly in a decentralized process where no accumulated or centralized knowledge or coordination is necessary. Efficient searching for agent groups that can facilitate the scheduling of tasks is accomplished through the use of a dynamic overlay structure of gateway agents and the exploitation of routing indices. The task allocation and the scheduling of complex tasks are accomplished by combining dynamic reorganization of agent groups and distributed constraint optimization methods. Experimental results display the efficiency of the proposed method.  相似文献   
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Photovoltaic (PV) simulators are indispensable for the operational evaluation of PV energy production system components (e.g. battery chargers, DC/AC inverters, etc.), in order to avoid the time-consuming and expensive field-testing process. In this paper, the development of a novel real-time PV simulator based on Field Programmable Gate Arrays (FPGAs), is presented. The proposed system consists of a Buck-type DC/DC power converter, which is controlled by an FPGA-based unit using the Pulse Width Modulation (PWM) principle. The system operator is able to define both the PV module type to be simulated and the environmental conditions under which the selected PV module operates. The proposed design method enhances the rapid system prototyping capability and enables the reduction of the power converter size and cost due to the high clock speed feature of the FPGA-based control unit. The experimental results indicate that, using the proposed method, the PV module current-voltage characteristics examined are reproduced with an average accuracy of 1.03%.  相似文献   
89.
Abstract  Permeable reactive barriers (PRBs) and flow-through reaction cells are fairly new passive treatment alternatives to conventional lime treatment of acidic rock drainage (ARD). They are ideal for the treatment of flowing ARD and are particularly useful when contaminants are likely to persist for several years. This paper describes column tests performed to simulate a PRB constructed using Bauxsol™, a chemically and physically treated bauxite refinery residue, as a reactive material. This experimentation shows promising results for the Bauxsol™ PRB method in neutralizing pH and removing metals from acidic mine effluents.  相似文献   
90.
Pattern Analysis and Applications - A correction to this paper has been published: 10.1007/s10044-021-01012-9  相似文献   
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