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Tribology Letters - Most asteroids with a diameter larger than $$\sim 300 \ {\mathrm{m}}$$ are rubble piles, i.e., consisting of more than one solid object. All asteroids are rotating but almost...  相似文献   
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The separation of binary mixtures which form azeotropes is not possible through conventional distillation and they are usually separated by extractive or azeotropic distillation. The optimization of extractive distillation columns is usually performed using a process simulator; however, normally, the result is only obtained after several simulations and the simultaneous analysis of several graphs. This paper sets out to present a systematic procedure, using a process simulator (Aspen Plus®), in order to obtain the optimum condition for extractive distillation columns. The optimization achieved is characterized by the fact that it is not necessary to perform various simulations, and it also avoids the simultaneous analysis of dozens of curves. The dehydration of aqueous mixtures of ethanol using ethylene glycol as solvent was the system chosen as a case study.  相似文献   
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The success of hydraulic simulation models of water distribution networks is associated with the ability of these models to represent real systems accurately. To achieve this, the calibration phase is essential. Current calibration methods are based on minimizing the error between measured and simulated values of pressure and flow. This minimization is based on a search of parameter values to be calibrated, including pipe roughness, nodal demand, and leakage flow. The resulting hydraulic problem contains several variables. In addition, a limited set of known monitored pressure and flow values creates an indeterminate problem with more variables than equations. Seeking to address the lack of monitored data for the calibration of Water Distribution Networks (WDNs), this paper uses a meta-model based on an Artificial Neural Network (ANN) to estimate pressure on all nodes of a network. The calibration of pipe roughness applies a metaheuristic search method called Particle Swarm Optimization (PSO) to minimize the objective function represented by the difference between simulated and forecasted pressure values. The proposed method is evaluated at steady state and over an extended period for a real District Metering Area (DMA), named Campos do Conde II, and the hypothetical network named C-town, which is used as a benchmark for calibration studies.  相似文献   
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This paper introduces DILIGENT, a digital library infrastructure built by integrating digital library and Grid technologies and resources. This infrastructure allows different communities to dynamically build specialised digital libraries capable to support the entire e-Science knowledge production and consumption life-cycle by using shared computing, storage, content, and application resources. The paper presents some of the main software services that implement the DILIGENT system. Moreover, it exemplifies the provided features by presenting how the DILIGENT infrastructure is being exploited in supporting the activity of user communities working in the Earth Science Environmental sector. This work is partially funded by the European Commission in the context of the DILIGENT project, under the 2nd call of FP6 IST priority.  相似文献   
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BACKGROUND: Systemic lupus erythematosus is a chronic, multisystem, autoimmune disorder that primarily affects women. Morbidity and mortality have improved for lupus patients during the last 15 years. An increased risk of malignancy in patients with lupus has been shown in some, but not all studies. The purpose of this study was to ascertain cancer risk in lupus patients by linking two disease registries. METHODS: Participants in the Chicago Lupus Cohort included 616 women with lupus who were residents of Cook County, Illinois. They were seen during 1985-1995 at 4 University, inner city, and suburban inpatient and outpatient clinics in Chicago. Malignancies occurring in these subjects during the study interval, 1985-1995, were identified from the Illinois State Cancer Registry by matching name, birthdate, and social security number. Standardized incidence ratios (SIRs) were estimated for all malignancies in this cohort of lupus patients using age, gender, and all race or race-stratified specific cancer incidence data from Cook County, Illinois. RESULTS: The registry linkage study with the Illinois State Cancer Registry documented that 30 women with lupus had a malignancy. The expected number of malignancies for women in the lupus cohort was 15.0. There were 8 cases of breast cancer and 4 each of lung and cervical cancer. In the remaining 14 women, 12 different types of cancers were noted. The SIR and 95% confidence interval (CI) for malignancy for all women with lupus in the study were 2.0 (1.4, 2.9) and lung cancer was the only individual cancer increased in all women--SIR and 95% CI were 3.1 (1.3, 7.9). In the analysis stratified by race, the risk of malignancy (SIR and 95% CI) was increased in Caucasian women, 2.3 (1.4, 3.9). Breast cancer was the only individual cancer increased in Caucasian women with lupus with an SIR and 95% CI of 2.9 (1.4, 6.4). CONCLUSIONS: Lupus patients have an increased risk of malignancy. Breast, lung, and gynecological malignancies were the most common malignancies observed in the cohort and breast cancer was significantly increased in Caucasian women.  相似文献   
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Magnetogenetics is emerging as a novel approach for remote‐controlled manipulation of cellular functions in tissues and organisms with high spatial and temporal resolution. A critical, still challenging issue for these techniques is to conjugate target proteins with magnetic probes that can satisfy multiple colloidal and biofunctional constraints. Here, semisynthetic magnetic nanoparticles are tailored based on human ferritin coupled to monomeric enhanced green fluorescent protein (mEGFP) for magnetic manipulation of proteins inside living cells. This study demonstrates efficient delivery, intracellular stealth properties, and rapid subcellular targeting of those magnetic nanoparticles via GFP–nanobody interactions. By means of magnetic field gradients, rapid spatial reorganization in the cytosol of proteins captured to the nanoparticle surface is achieved. Moreover, exploiting efficient nanoparticle targeting to intracellular membranes, remote‐controlled arrest of mitochondrial dynamics using magnetic fields is demonstrated. The studies establish subcellular control of proteins and organelles with unprecedented spatial and temporal resolution, thus opening new prospects for magnetogenetic applications in fundamental cell biology and nanomedicine.  相似文献   
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Melamine is a nitrogen-rich compound (about 66%) whose fraudulent addition to foods aims to increase the apparent protein content. In 2008, melamine adulteration incidents occurred in China caused several deaths in humans from kidney failure and other health problems. This issue prompted private as well as governmental laboratories to develop several analytical methods in order to determine melamine in foods. This review aims to provide an overview of the analytical techniques currently available in the literature for melamine detection and measurement in milk and dairy products, including a specific section related to sample preparation. Recent studies concerning conventional (both screening and confirmatory) methods are reported, and technical and critical issues are discussed for each technique (liquid and gas chromatography, mass spectrometry, liquid chromatography coupled to mass spectrometry, gas chromatography coupled to mass spectrometry, and capillary electrophoresis). These techniques, very sensitive and specific but also time-consuming, may require tedious sample preparation, costly instrumentation, and skilled personnel. Therefore, new innovative detection methods are also provided, focusing attention on immunoassay, sensor technology, vibrational spectroscopy coupled to chemometrics, hyperspectral imaging, micellar liquid chromatography, magnetic resonance spectroscopy, and chemiluminescence.  相似文献   
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Tony Manzi 《Housing Studies》2017,32(2):209-224
The relationship between professionalism, education and housing practice has become increasingly strained following the introduction of austerity measures and welfare reforms across a range of countries. Focusing on the development of UK housing practice, this article considers how notions of professionalism are being reshaped within the context of welfare retrenchment and how emerging tensions have both affected the identity of housing professionals and impacted on the delivery of training and education programmes. The article analyses the changing knowledge and skills valued in contemporary housing practice and considers how the sector has responded to the challenges of austerity. The central argument is that a dominant logic of competition has culminated in a crisis of identity for the sector. Although the focus of the article is on UK housing practice, the processes identified have a wider relevance for the analysis of housing and welfare delivery in developed economies.  相似文献   
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