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41.
Yarlagadda S Gude VG Camacho LM Pinappu S Deng S 《Journal of hazardous materials》2011,192(3):1388-1394
In this study, the feasibility of the direct contact membrane distillation (DCMD) process to recover arsenic, uranium and fluoride contaminated saline ground waters was investigated. Two types of membranes (polypropylene, PP; and polytetrafluoroethylene, PTFE) were tested to compare the permeate production rates and contaminant removal efficiencies. Several experiments were conducted to study the effect of salts, arsenic, fluoride and uranium concentrations (synthetic brackish water with salts: 1000-10,000 ppm; arsenic and uranium: 10-400 ppb; fluoride: 1-30 ppm) on the desalination efficiency. The effect of process variables such as feed flow rate, feed temperature and pore size was studied. The experimental results proved that the DCMD process is able to achieve over 99% rejection of the salts, arsenic, fluoride and uranium contaminants and produced a high quality permeate suitable for many beneficial uses. The ability to utilize the low grade heat sources makes the DCMD process a viable option to recover potable water from a variety of impaired ground waters. 相似文献
42.
Carlos Garcia-Padilla Estefanía Lozano-Velasco María del Mar Muoz-Gallardo Juan Manuel Castillo-Casas Sheila Cao-Carrillo Francisco Jos Martínez-Amaro Virginio García-Lpez Amelia Arnega Diego Franco Virginio García-Martínez Carmen Lpez-Snchez 《International journal of molecular sciences》2022,23(15)
Various treatments based on drug administration and radiotherapy have been devoted to preventing, palliating, and defeating cancer, showing high efficiency against the progression of this disease. Recently, in this process, malignant cells have been found which are capable of triggering specific molecular mechanisms against current treatments, with negative consequences in the prognosis of the disease. It is therefore fundamental to understand the underlying mechanisms, including the genes—and their signaling pathway regulators—involved in the process, in order to fight tumor cells. Long non-coding RNAs, H19 in particular, have been revealed as powerful protective factors in various types of cancer. However, they have also evidenced their oncogenic role in multiple carcinomas, enhancing tumor cell proliferation, migration, and invasion. In this review, we analyze the role of lncRNA H19 impairing chemo and radiotherapy in tumorigenesis, including breast cancer, lung adenocarcinoma, glioma, and colorectal carcinoma. 相似文献
43.
Iván Cores Gabriel Rodríguez Mará J. martín Patricia González Roberto R. Osorio 《New Generation Computing》2013,31(3):163-185
The execution times of large-scale parallel applications on nowadays multi/many-core systems are usually longer than the mean time between failures. Therefore, parallel applications must tolerate hardware failures to ensure that not all computation done is lost on machine failures. Checkpointing and rollback recovery is one of the most popular techniques to implement fault-tolerant applications. However, checkpointing parallel applications is expensive in terms of computing time, network utilization and storage resources. Thus, current checkpoint-recovery techniques should minimize these costs in order to be useful for large scale systems. In this paper three different and complementary techniques to reduce the size of the checkpoints generated by application-level checkpointing are proposed and implemented. Detailed experimental results obtained on a multicore cluster show the effectiveness of the proposed methods to reduce checkpointing cost. 相似文献
44.
A combined idle channel assignment (ICA) and fixed channel assignment (FCA) scheme is proposed to improve the traffic performance in a hierarchical network. This dual-mode network integrates the Frequency Division Duplex (FDD) and Time Division Duplex (TDD) modes of the Universal Mobile Telecommunication System (UMTS) and Terrestrial Radio Access (UTRA) in a given cell. This approach includes a high traffic load area and a blocked area as an example to evaluate the traffic performance. The ICA threshold and network timeout period effects on the traffic performance of this integrated dual-mode network are also investigated. The analytical results show that the handoff failure probabilities of the integrated dual-mode network can be reduced significantly with a minimal increase in the new call blocking probability when the combined ICA and FCA scheme replaces the FCA scheme. The integrated dual-mode network using the combined ICA and FCA scheme also increases the carried traffic. The traffic performance improvements for non-uniformly generated new calls are more significant than those for uniformly generated new calls when the combined ICA and FCA scheme is used. An increase in the high ICA threshold will result in an increase in the total carried traffic and an increase in the new call blocking and handoff failure probabilities for higher-tiered and low-tiered systems located in the high traffic load area. The traffic performance was evaluated using the discrete time simulation method to validate the analysis results. 相似文献
45.
The mixed-signal programmable system-on-chip (PSOC) architecture for high-volume low-cost applications is presented. Programmable analog, digital, and clocking circuits are combined with flash memory and a microcontroller to provide a platform for single-chip solutions for low-cost consumer applications. Both programmable analog and digital circuits are designed to support a moderate level of abstraction, balancing flexibility against cost and performance. A rough comparison of alternative approaches based on functionality and cost is presented. 相似文献
46.
Ricardo García Elena Verdú Luisa M. Regueras Juan P. de Castro María J. Verdú 《Expert systems with applications》2013,40(10):4096-4105
Web mapping has become a popular way of distributing interactive digital maps over the internet. Instead of dynamically generating map images on the fly, those can be pre-generated and served from a server-side cache for faster retrieval. However, these caches can grow unmanageably in size when the cartography covers mid to large areas for multiple rendering scales. This forces modest organizations to use partial caches containing just a subset of the total tiles, and makes their services less attractive than other mapping services like Google Maps or Microsoft Bing Maps. This work proposes a neural-network-based intelligent system that predicts which areas are likely to be requested in the future from a catalog of geographic features and a short history of past requests. These priority regions can be used by a tile prefetching policy to achieve an optimal population of the cache. Neural networks are trained and validated using supervised learning with real data-sets from a public nation-wide web map service. Trace-driven simulations demonstrate that accurate long-term predictions, up to 90% in terms of cache-hit ratio, can be obtained with the proposed model by prefetching a low fraction, only the 20% of the total tiles, and with a short training period. 相似文献
47.
Andrés Vignaga Frédéric Jouault María Cecilia Bastarrica Hugo Brunelière 《Software and Systems Modeling》2013,12(1):105-119
Model management is essential for coping with the complexity introduced by the increasing number and varied nature of artifacts involved in model-driven engineering-based projects. Global model management (GMM) addresses this issue by enabling the representation of artifacts, particularly transformation composition and execution, within a model called a megamodel. Type information about artifacts can be used for preventing type errors during execution. Built on our previous work, in this paper we present the core elements of a type system for GMM that improves its original typing approach and enables both typechecking and type inference on artifacts within a megamodel. This type system is able to deal with non-trivial situations such as the use of higher order transformations. We also present a prototypical implementation of such a type system. 相似文献
48.
Nicolette Pegels Isabel González Irene Martín María Rojas Teresa García Rosario Martín 《Food Control》2011,22(8):1189-1196
A TaqMan real-time polymerase chain reaction (PCR) method was developed for specific detection of bovine, ovine and caprine processed animal protein (PAP) in industrial feedstuffs. The method uses species-specific primers and probes targeting short mitochondrial D-loop sequences, and a positive amplification control based on 18S rRNA gene. The applicability of the real-time PCR protocol was assessed through analysis of 126 industrial feed samples that were manufactured to reproduce rendering processes of commercial feeds destined for farmed animals. The assay successfully classified samples as positive or negative according to the ruminant composition, enabling qualitative detection of banned material in feeds at levels as low as 0.1%. Although the method provides quantitative potential, results suggest that the real quantitative capability of the assay is limited by the existing variability in terms of composition and processing treatments of the feeds, which affect the amount and quality of amplifiable DNA. 相似文献
49.
50.
Incorporation of process integration into life cycle analysis for the production of biofuels 总被引:1,自引:1,他引:0
Pascale Chouinard-Dussault Laura Bradt José María Ponce-Ortega Mahmoud M. El-Halwagi 《Clean Technologies and Environmental Policy》2011,13(5):673-685
This article presents a new approach for incorporating process-integration tools into life cycle analysis (LCA) for biofuel production. Process synthesis techniques using mass- and energy-integration tools are employed to generate various scenarios for reducing mass and energy consumption in the process. The global implications of these changes and the associated trade-offs are assessed using the LCA tool: GREET. The developed approach enables the consideration of several levels of process integration while tracking the process economics and the reduction of the net greenhouse gas emissions. Several cases of biofuels with different processing technologies have been considered in this study, and the results show that when the process-integration tools are effectively utilized and combined with LCA, better insights are obtained and the net greenhouse gas emissions decrease drastically for different biofuels. 相似文献