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Probabilistic estimate of rock mass static and dynamic demands for underground excavation stabilisation

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第3期11卷 481-493页

作者： Ernesto Villaescusa Alan Thompson christopher Windsor Western Australia School of Mines Curtin UniversityLocked Bag 30KalgoorlieWA 6433Australia Alan Thompson Geotechnology Pty Ltd. 40B Windich StreetEsperanceWA 6450Australia

Excavation damage under high in situ stress depends largely upon the potential block size associated with any violent *** size and shape of the dynamic instability are largely controlled by the location,orientation and extent of the pre-existing geological discontinuities.A new methodology is presented in which the rock mass demand can be expressed in terms of the mass in tonnes of unstable rock that is ejected per unit area of the excavation surface where failure occurs.A probabilistic approach has been implemented to estimate the potential rock mass instabilities and their associated static and dynamic *** new methodology considers that the strain energy released by the rock mass during violent stress-driven failure is largely converted into kinetic energy of ejection for *** estimated dynamic demand has been favourably compared with observations of rock mass damage in a number of underground excavations.

关键词： Geological structures Probabilistic design Underground excavations High stresses Dynamic and static demands Deep mining

Obstructive sleep apnea syndrome and fatty liver: Association or causal link?

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World Journal of Gastroenterology 2010年第34期16卷 4243-4252页

作者： Mohamed H Ahmed christopher D Byrne Chemical Pathology Department Southampton University Hospital NHS Trust Southampton SO16 6YD United Kingdom Endocrinology and Metabolism DOHaD Division University of Southampton and Southampton University Hospitals Trust Southampton SO16 6YD United Kingdom

Obstructive sleep apnea (OSA) is a complex disorder that consists of upper airway obstruction, chronic intermittent hypoxia and sleep fragmentation. OSA is well known to be associated with hypoxia, insulin resistance and glucose intolerance, and these factors can occur in the presence or absence of obesity and metabolic syndrome. Although it is well established that insulin resistance, glucose intolerance and obesity occur frequently with non-alcoholic fatty liver disease (NAFLD), it is now becoming apparent that hypoxia might also be important in the development of NAFLD, and it is recognized that there is increased risk of NAFLD with OSA. This review discusses the association between OSA, NAFLD and cardiovascular disease, and describes the potential role of hypoxia in the development of NAFLD with OSA.

关键词： Sleep apnea syndrome Hyperlipidemia Non-alcoholic fatty liver disease Insulin resistance

Geographic context-aware text mining:enhance social media message classification for situational awareness by integrating spatial and temporal features

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International Journal of Digital Earth 2021年第11期14卷 1721-1743页

作者： christopher Scheele Manzhu Yu Qunying Huang Spatial Computing and Data Mining Lab Department of GeographyUniversity of Wisconsin-MadisonMadisonWIUSA Department of Geography Pennsylvania State UniversityUniversity ParkPAUSA

To find disaster relevant social media messages,current approaches utilize natural language processing methods or machine learning algorithms relying on text only,which have not been perfected due to the variability and uncertainty in the language used on social media and ignoring the geographic context of the messages when ***,a disaster relevant social media message is highly sensitive to its posting location and ***,limited studies exist to explore what spatial features and the extent of how temporal,and especially spatial features can aid text *** paper proposes a geographic context-aware text mining method to incorporate spatial and temporal information derived from social media and authoritative datasets,along with the text information,for classifying disaster relevant social media *** work designed and demonstrated how diverse types of spatial and temporal features can be derived from spatial data,and then used to enhance text *** deep learning-based method and commonly used machine learning algorithms,assessed the accuracy of the enhanced text-mining *** performance results of different classification models generated by various combinations of textual,spatial,and temporal features indicate that additional spatial and temporal features help improve the overall accuracy of the classification.

关键词： Spatial data science spatially enabled text mining situational awareness deep learning GeoAI spatial features

Common and distinct regulation of human and mouse brown and beige adipose tissues： a promising therapeutic target for obesity

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Protein & Cell 2017年第6期8卷 446-454页

作者： Xuejiao Liu christopher Cervantes Feng Liu Department of Metabolism and Endocrinology Metabolic Syndrome Research Center of Central South University The Second Xianqya Hospital Central South University Changsha 410011 China Department of Pharmacology University of Texas Health Science Center at San Antonio San Antonio TX 78229 USA

Obesity, which underlies various metabolic and cardio- vascular diseases, is a growing public health challenge for which established therapies are inadequate. Given the current obesity epidemic, there is a pressing need for more novel therapeutic strategies that will help adult individuals to manage their weight. One promising therapeutic intervention for reducing obesity is to enhance energy expenditure. Investigations into human brown fat and the recently discovered beige/brite fat have galvanized intense research efforts during the past decade because of their pivotal roles in energy dissi- pation. In this review, we summarize the evolution of human brown adipose tissue （hBAT） research and dis- cuss new in vivo methodologies for evaluating energy expenditure in patients. We highlight the differences between human and mouse BAT by integrating and comparing their cellular morphology, function, and gene expression profiles. Although great advances in hBAT biology have been achieved in the past decade, more cellular models are needed to acquire a better under- standing of adipose-specific processes and molecular mechanisms. Thus, this review also describes the development of a human brown fat cell line, which could provide promising mechanistic insights into hBAT function, signal transduction, and development. Finally, we focus on the therapeutic potential and current limi- tations of hBAT as an anti-glycemic, anti-lipidemic, and weight loss-inducing ＇metabolic panacea＇.

关键词： human brown adipose tissue energymetabolism obesity

Repeated hydrogen peroxide dosing briefly reduces cyanobacterial blooms and microcystin while increasing fecal bacteria indicators in a eutrophic pond

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Journal of Environmental Sciences 2023年第2期124卷 522-543页

作者： Mark W.Lusty christopher J.Gobler School of Marine and Atmospheric Sciences Stony Brook UniversitySouthamptonNY 11968USA

This study explored the effects of H_(2)O_(2)on Cyanobacteria and non-target microbes using fluorometry,microscopy,flow cytometry,and high throughput DNA sequencing of the 16S rRNA gene during a series of mesocosm and whole-ecosystem experiments in a eutrophic pond in NY,*** addition of H_(2)O_(2)(8 mg/L)significantly reduced Cyanobacteria concentrations during a majority of experiments(66%;6 of 9)and significantly increased eukaryotic green and unicellular brown algae in 78%and 45%of experiments,*** heterotrophic bacteria declined significantly following H_(2)O_(2)addition in all experiments,bacteria indicative of potential fecal contamination(Escherichia coli,Enterococcus,fecal coliform bacteria)consistently and significantly increased in response to H_(2)O_(2),evidencing a form of‘pollution swapping’.H_(2)O_(2)more effectively reduced Cyanobacteria in enclosed mesocosms compared to whole-ecosystem *** whole-pond H_(2)O_(2)applications over a twoyear period temporarily reduced cyanobacterial levels but never reduced concentrations below bloom thresholds and populations always rebounded in two weeks or *** bacterial phyla of Cyanobacteria,Actinobacteria,and Planctomycetes were the most negatively impacted by H_(2)O_(2).Microcystis was always reduced by H_(2)O_(2),as was the toxin microcystin,but Microcystis remained dominant even after repeated H_(2)O_(2)*** H_(2)O_(2)favored the growth of eukaryotic algae over potentially harmful Cyanobacteria,the inability of H_(2)O_(2)to end cyanobacterial blooms in this eutrophic waterbody suggests it is a non-ideal mitigation approach in high biomass ecosystems and should be used judiciously due to potential negative impacts on non-target organisms and promotion of bacteria indicative of fecal contamination.

关键词： Indicator bacteria Toxic cyanobacteria Microcystin Microcystis Hydrogen peroxide Bacteria Enterococcus E.coli Pollution swapping

Assessment of potential impacts to surface and subsurface water bodies due to longwall mining

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International Journal of Mining Science and Technology 2017年第1期27卷 57-64页

作者： christopher new.an Zacharias Agioutantis Gabriel Boede Jimenez Leon Department of Mining Engineering University of KentuckyLexingtonKY 40506USA

Ground movements due to longwall mining operations have the potential to damage the hydrological balance within as well as outside the mine permit area in the form of increased surface ponding and changes to hydrogeological properties. Recently, the Office of Surface Mining, Reclamation and Enforcement(OSMRE) in the USA, has completed a public comment period on a newly proposed rule for the protection of streams and groundwater from adverse impacts of surface and underground mining operations(80 FR 44435). With increased community and regulatory focus on mining operations and their potential to adversely affect streams and groundwater, now there is a greater need for better prediction of the possible effects mining has on both surface and subsurface bodies of water. With mining induced stress and strain within the overburden correlated to changes in the hydrogeological properties of rock and soil, this paper investigates the evaluation of the hydrogeological system within the vicinity of an underground mining operation based on strain values calculated through a surface deformation prediction model. Through accurate modeling of the pre- and post-mining hydrogeological system, industry personnel can better depict mining induced effects on surface and subsurface bodies of water aiding in the optimization of underground extraction sequences while maintaining the integrity of water resources.

关键词： Streams Aquifers Ground strain Coal mining

High resolution tracking of adult horseshoe crabs Limulus polyphemus in a new Hampshire estuary using fixed array ultrasonic telemetry

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Current Zoology 2010年第5期56卷 599-610页

作者： Winsor H.WATSON Ⅲ christopher C.CHABOT Department of Biological Sciences University of New Hampshire Department of Biology Plymouth State University

While several studies have documented the large-scale, seasonal movements of horseshoe crabs, little is known about their fine-scale, daily movement patterns. In this study we used a fixed array ultrasonic telemetry system to track the movements of 12 male and 16 female horseshoe crabs in the Great Bay estuary, new Hampshire. Data were obtained during the mating season, as well as during the remainder of the summer and fall, in the years 2005-2008. During the mating season animals were often, but not always, active during the high tides when they were approaching and leaving the spawning beaches. On average, both males and females approached mating beaches during 33% of the high tides they experienced and they most often made the tran- sition from being inactive to active during the last two hours of an incoming tide. From April-October horseshoe crabs were significantly more active during high tide periods vs low tide periods, with no clear preference for diurnal vs nocturnal activity. After the mating season ended horseshoe crabs continued to move into shallower water at high tide and then return to deeper water at low tide. Observations by SCUBA divers suggest that during these excursions into the mudflats horseshoe crabs were digging pits in the sediment while foraging for food. Thus, the tidal rhythm of activity that has been so well documented during the mating season probably persists into the fall, and primarily involves foraging activities

关键词： Telemetry Tracking Movements Mating Foraging Estuary

Effect of slab width on choice of appropriate casting speed in steel production

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Journal of Iron and Steel Research International 2022年第1期29卷 71-79页

作者： Daniel christopher Merten Marc-Thorsten Hütt Yilmaz Uygun Department of Mathematics and Logistics Jacobs University BremenBremen 28759Germany Department of Life Sciences and Chemistry Jacobs University BremenBremen 28759Germany

In steel continuous casting(CC),the choice of the appropriate speed at which the slab is cast can be influenced by many different factors and *** the slab thickness seems to have the biggest impact,other features like the slab width have been consistently *** fact,the slab width practically limits the casting speed via the mass flow constraint which governs the input and output balance at the ***,we present a case study that aims at analyzing steel production data from the perspective of casting speed *** studying the speed fluctuations of an industrial CC machine,we identify a strategic regime change toward a stricter consideration of the mass flow *** regime change manifests itself in a significant increase in the correlation between the actual casting speed and the maximal speed associated with the mass flow *** the surface,taking greater account of the input and output balance at the tundish has reduced the productivity of the continuous caster;however,one can argue that the lessened yield is compensated by a diminished risk of eventual slab *** the perspective of this trade-off,we establish a visualization technique that enables us to pinpoint the boundary beyond which one strategic regime becomes economically more advantageous than the other.

关键词： Continuous casting Casting speed Slab width Slab thickness Mass flow constraint Machine length constraint

Gold Nanozymes:From Concept to Biomedical Applications

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Nano-Micro Letters 2021年第1期13卷 138-173页

作者： Javier Lou‑Franco Bhaskar Das christopher Elliott Cuong Cao Institute for Global Food Security School of Biological SciencesQueen’s University of Belfast19 Chlorine GardensBelfast BT95DLUK Present Address:Department of Biotechnology and Medical Engineering National Institute of Technology RourkelaRourkelaIndia

In recent years,gold nanoparticles have demonstrated excellent enzyme-mimicking activities which resemble those of peroxidase,oxidase,catalase,superoxide dismutase or ***,merged with their ease of synthesis,tunability,biocompatibility and low cost,makes them excellent candidates when compared with biological enzymes for applications in biomedicine or biochemical ***,over 200 research papers have been systematically reviewed to present the recent progress on the fundamentals of gold nanozymes and their potential *** review reveals that the morphology and surface chemistry of the nanoparticles play an important role in their catalytic properties,as well as external parameters such as pH or ***,real applications often require specific biorecognition elements to be immobilized onto the nanozymes,leading to unexpected positive or negative effects on their ***,rational design of efficient nanozymes remains a challenge of paramount *** implementation paths have already been explored,including the application of peroxidase-like nanozymes for the development of clinical diagnostics or the regulation of oxidative stress within cells via their catalase and superoxide dismutase *** review also indicates that it is essential to understand how external parameters may boost or inhibit each of these activities,as more than one of them could ***,further toxicity studies are required to ensure the applicability of gold nanozymes in *** challenges and future prospects of gold nanozymes are discussed in this review,whose significance can be anticipated in a diverse range of fields beyond biomedicine,such as food safety,environmental analyses or the chemical industry.

关键词： Gold nanoparticles Catalysis Nanozymes Diagnosis Nanomedicine