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Xenoestrogens challenge 17β-estradiol protective effects in colon cancer

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World Journal of Gastrointestinal Oncology 2014年第3期6卷 67-73页

作者： maria Marino Department of Science University Roma TreI-00146 RomaItaly

Several epidemiological,cellular,and molecular studies demonstrate the role of environmental chemicals with endocrine disrupting activities,typical of Westernized societies,in the pathogenesis of numerous diseases including *** this information,the design and execution of studies on endocrine disruptors are not yet cognizant that the specific actions of individual hormones often change with development and ageing,they may be different in males and females and may be mediated by different receptors isoforms expressed in different tissues or at different life *** statements are particularly true when assessing the hazard of endocrine disruptors against 17β-estradiol(E2)actions in that this hormone is crucial determinant of sexrelated differences in anatomical,physiological,and behavioral traits which characterize male and female ***,E2 is also involved in *** oncogenic effects of E2 have been investigated extensively in breast and ovarian cancers where hormone-receptor modulators are now an integral part of targeted *** is known about the E2preventive signalling in colorectal cancer,although this disease is more common in men than women,the difference being more striking amongst pre-menopausal women and age-matched *** review aims to dissect the role and action mechanisms of E2 in colorectal cancer evaluating the ability of estrogen disruptors(i.e.,xenoestrogens)in impair these E2 *** discussed here lead to define the possible role of xenoestrogens in the impairment and/or activation of E2signals important for colorectal cancer prevention.

关键词： 17β-Estradiol Estrogen receptors Xenoestrogens Bisphenol A Flavonoids Colorectal cancer

Rare earth elements in flotation products of coals from East Kootenay coalfields,British Columbia

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Journal of Rare Earths 2019年第12期37卷 1366-1372页

作者： Vinoth Kumar Kuppusamy maria Holuszko NBK Institute of Mining Engineering University of British Columbia

With the identification of coal deposits that are enriched in rare earth elements(REEs)across the world,coal and coal by-products are considered as an alternative source for REEs due to the combined supply and demand restrictions for these *** are being conducted to recover these elements from various coal *** this study,coal samples from the East Kootenay coalfields in British Columbia,Canada were examined for the presence of REEs in run-of-mine coal samples and flotation *** reveal that on an ash basis,the concentration of REEs varies from 174 to 1038 mg/kg in the *** understand the REE as sociation,which is essential for extraction purposes,a three-step sequential extraction process along with a mineralogical evaluation using scanning electron microscopy(SEM)with energy dispersive X-ray spectroscopy(EDX)and quantitative X-ray diffraction(XRD)data was *** is found that a significant portion of REEs in the feed samples were reported to middling and tailings *** mineralogical analyses reveal REE association with aluminosilicate mineral in the samples.

关键词： Rare earth elements Coal East Kootenay coalfields Mode of occurrence

Synthetic gauge fields for ultracold atoms

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National Science Review 2016年第2期3卷 166-167页

作者： Ana maria Rey JILA NIST and Department of PhysicsUniversity of Colorado

Ultracold gases are remarkably versatile and controllable systems with untapped potential to emulate a variety of quantum phenomena[1].Atoms are,however,electrically neutral and therefore it is highly desirable to make them behave as charged *** capability has recently been demonstrated in a series of recent experiments[2-4].Although many challenges remain ahead,

关键词： Synthetic gauge fields for ultracold atoms

Robust Control of a Bevel-Tip Needle for Medical Interventional Procedures

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IEEE/CAA Journal of Automatica Sinica 2020年第1期7卷 244-256页

作者： Surender Hans Felix Orlando maria Joseph Department of Electrical Engineering Indian Institute of Technology RoorkeeRoorkeeUttarakhand 247667India

In minimally invasive surgery, one of the main objectives is to ensure safety and target reaching accuracy during needle steering inside the target organ. In this research work, the needle steering approach is determined using a robust control algorithm namely the integral sliding mode control(ISMC) strategy to eliminate the chattering problem associated with the general clinical scenario. In general, the discontinuity component of feedback control input is not appropriate for the needle steering methodology due to the practical limitations of the driving actuators. Thus in ISMC, we have incorporated the replacement of the discontinuous component using a super twisting control(STC)input due to its unique features of chattering elimination and disturbance observation characteristics. In our study, the kinematic model of an asymmetric flexible bevel-tip needle in a soft-tissue phantom is used to evaluate stability analysis. A comparative study based on the analysis of chattering elimination is executed to determine the performance of the proposed control strategy in real-time needle steering with conventional sliding mode control using vision feedback through simulation and experimental results. This validates the efficacy of the proposed control strategy for clinical needle steering.

关键词： Minimal invasive surgery needle steering nonholonomic system robust control sliding mode control

Trends and advances in the development of coal fly ash-based materials for application in hydrogen-rich gas production:A review

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Journal of Energy Chemistry 2022年第10期31卷 485-512,I0013页

作者： Kang Gao maria C.Iliuta Department of Chemical Engineering Laval UniversityQuébecQC G1V 0A6Canada

Coal fly ash(FA),a valuable industrial solid residue generated from coal combustion,is composed of various metal oxides and has a high thermal *** that the coal-based energy will continue to account for a significant portion of global electricity generation in the coming years,the lack of effective management strategies exacerbates the threat of FA wastes to the surrounding environment and human *** a sustainable development,green and renewable hydrogen economy and CO_(2)capture efforts provide appealing opportunities to valorize FA as catalysts and/or sorbents due to their appealing physicochemical *** applications along with carbon neutrality are potential strategies to mitigate climate change crisis,but high processing costs(catalysts/sorbents)are challenging to realize this *** this context,the utilization of FA not only enhances industrial competitiveness(by reducing manufacturing costs),but also provides ecologically friendly approaches to minimizing this solid *** state-of-the-art review highlights a wide-ranging outlook on the valorization of FA as catalysts and sorbents for hydrogen-rich gas production via conventional/intensified processes(CO_(2)/H_(2)O reforming,ammonia decomposition,hydride hydrolysis).The fundamental physicochemical characterizations and hazards/utilization of FA,which significantly affect the FA's utilization in various fields,are first *** influence of several factors(like FA types and catalysis/sorption operation conditions)on the activity performance of FA-based materials is then discussed in *** critical review aims to open the window to further innovative ideas regarding the application of different FA residues in other catalytic and sorption processes.

关键词： Coal fly ash Catalyst/support High temperature CO_(2)sorbent Bifunctional material Hydrogen production Conventional/intensified process

Colonic polyps: Is it useful to characterize them with advanced endoscopy?

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World Journal of Gastroenterology 2014年第26期20卷 8449-8457页

作者： maria Lopez-Ceron Erwin Sanabria maria Pellise Endoscopy Unit Department of GastroenterologyInstitut de Malalties Digestives i MetabòliquesHospital ClinicCentro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd)Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS)

There have been major developments in endoscopic imaging techniques in recent *** with high definition and magnification can provide high quality images that allow for the histological estimation of lesions in vivo and in situ when combined with ancillary enhancement techniques such as chromoendoscopy(CE)and virtual CE(narrow band imaging fujinon intelligent chromoendoscopy,or i-Scan).Despite the enormous potential for these advanced techniques,their value and feasibility in the clinic are still doubted,particularly in cases of colonic polyps that are slated for removal,where in vivo characterization may be deemed ***,there are several advantages offered by such advanced endoscopic *** with or without magnification demonstrates highly accurate histology and invasion depth prediction,and virtual CE is a feasible and less cumbersome alternative to CE in terms of histological estimation,though not sufficiently accurate for depth invasion ***,the supplementary information provided by advanced imaging systems can assist the endoscopist in the selection of a strategic approach,such as in deciding whether a colonic lesion should be resected,left in situ,or requires more intensive surgical ***,advanced high-resolution imaging techniques may be more cost effective,such that histopathology of lowrisk lesions following resection can be *** results of these evaluations and comparisons with traditional CE are presented and *** together,the benefits provided by these advanced capabilities justify their development,and advocates their use for the treatment and management of colonic polyps.

关键词： Colon polyps Chromoendoscopy Narrow band imaging Fujinon intelligent chromoendoscopy i-Scan Colonoscopy Optical biopsy

Body size structure of Pleistocene mammalian communities: what support is there for the “island rule”?

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Integrative Zoology 2009年第4期4卷 341-356页

作者： maria R.PALOMBO Department of Earth Sciences University of Rome“La Sapienza”RomeItaly

Islands are often regarded by scientists as living laboratories of evolution and an optimal context for the study of forces influencing evolution and *** main issues have been attentively scrutinized and debated:the loss of biodiversity and the peculiar changes undergone by island settlers,primarily changes in size of endemic *** time,several hypotheses have been formulated to explain the causal mechanism of body size *** of those islands where mainland taxa migrate more than once provide the most interesting data to answer the question of whether or not trends of insular taxa result from a predictable response to differences in competition and availability of niches between insular and mainland *** contribute to the debate,the body size structure of the Pleistocene mammalian faunas from two Mediterranean islands,Sicily and Crete,were analyzed and compared with the structure of coeval mainland *** results obtained suggest that:(i)size of endemic species does not directly depend on the area of islands;(ii)evolution and size of endemic species seems somewhat affected by the degree of isolation(constraining coloniza-tion from mainland)and physiography(sometimes permitting adaptive radiation);(iii)in unbalanced insular communities,the shift in size of non-carnivorous species largely depends on the nature of competing species;and(iv)body size of carnivorous species mainly depends on the size of the most available ***,it is rational to suppose that the body size of insular mammals mainly results from the peculiar biological dynamics that characterizes unbalanced insular *** interaction,particularly the intraguild competition,is the major driver behind the evolution of insular communities,leading towards an optimization of energy balance through a change in body size of endemic settlers.

关键词： body size islands mammals Mediterranean Pleistocene.Body size structure of Sicilian and Cretan Pleistocene fauna

Calcareous nannoplankton dating of the Late Quaternary deposits in Greece and the eastern Mediterranean: Case studies from terrestrial and marine sites

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Journal of Palaeogeography 2015年第4期4卷 349-358页

作者： maria V.Triantaphyllou Faculty of Geology and Geoenvironment University of Athens

The distribution and abundance of Emiliania huxleyi（E. huxleyi） assemblages in the marine sediments of the Aravonitsa Plateau, Greece, and from the eastern Mediterranean are used（1） to evaluate the calcareous nannoplankton NN21 a and NN21 b biozones and the NN21a/NN21 b boundary, and（2） to analyze the palaeoenvironmental and palaeoclimatic conditions prevailing in this interval. The sediment succession displays varied E. huxleyi assemblages and these are interpreted as reflecting climatic variability during marine isotope stages MIS 1-8.

关键词： Emiliania huxleyi biostratigraphy palaeoclimatic conditions Greece eastern Mediterranean

Past climate and vegetation in Southeast Bulgaria——a study based on the late Miocene pollen record from the Tundzha Basin

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Journal of Palaeogeography 2019年第1期8卷 43-67页

作者： Dimiter Ivanov maria Lazarova Institute of Biodiversity and Ecosystem Research Bulgarian Academy of Sciences

The results of palynological studies on the late Miocene freshwater deposits of the Tundzha Basin(Southeast Bulgaria, SE Europe) are presented. The basin is relatively well known in terms of geology and *** age of sediments in the Tundzha Basin ranges between the late Miocene to the Pliocene, based on mammal and diatom fossils. We carried out a palynological analysis of clayey sediments interlayered with coal beds from four cores and from one outcrop, aiming to obtain information about the composition and the structure of fossil vegetation. The ratios between the main floristic elements and the composition of the fossil flora are analysed and discussed from a palaeoecological point of view. Several main vegetation palaeocommunities were recorded:swamp forests, mixed mesophytic, communities of aquatic plants, and herbaceous palaeocoenoses. The changes in vegetation and in plant diversity are identified. The palaeoclimate analysis indicates a warm temperature climate with high rainfall and mild winter temperatures, without seasonal drier conditions. The early Pontian climate was about 3–4 ℃ warmer than today, with rainfalls per year at least 300 mm higher than today. The results of palaeoecological analysis of the flora and of the quantitative palaeoclimate data show that the climate in the Southeast Bulgaria indicates a climate change towards slight cooling and some drying. This event is consistent with the period of accumulation of the upper, undivided part of the Elhovo Formation.

关键词： Palynology Palaeobotany Coexistence approach Neogene Tundzha Basin Bulgaria