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exploring the mass gap:Black holes in green pea galaxies

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Science China(Physics,Mechanics & Astronomy) 2024年第10期67卷 170-171页

作者： james e.Rhoads School of earth and Space exploration Arizona State UniversityTempeAZ 85287USA

We know about black holes primarily on two mass scales(e.g.,see Figure 22 of ref.[1]).Supermassive black holes inhabit the centers of galaxies,where they sometimes power active galactic nuclei(AGN).Their populations can be probed through AGN surveys,tidal disruption event surveys,and(in the closest galaxies)stellar and gas dynamics in the innermost regions where the black hole dominates the gravitational potential.

关键词： galaxies tidal galactic

Prediction of performance, combustion and emission characteristics of diesel-thermal cracked cashew nut shell liquid blends using artificial neural network

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Frontiers in energy 2016年第1期10卷 114-124页

作者： Arunachalam VeLMURUGAN Marimuthu LOGANATHAN e. james GUNASeKARAN Department of Mechanical engineering Annamalai University Annamalainagar 608002 India

This paper explores the use of artificial neural networks （ANN） to predict performance, combustion and emissions of a single cylinder, four stroke stationary, diesel engine operated by thermal cracked cashew nut shell liquid （TC-CNSL） as the biodiesel blended with diesel. The tests were performed at three different injection timings （21°, 23°, 25℃A bTDC） by changing the thickness of the advance shim. The ANN was used to predict eight different engine-output responses, namely brake thermal efficiency （BTe）, brake specific fuel consumption （BSFC）, exhaust gas temperature （eGT）, carbon monoxide （CO）, oxide of nitrogen （NOx）, hydrocarbon （HC）, maximum pressure （Pm~,,） and heat release rate （HRR）. Four pertinent engine operating parameters, i.e., injection timing （IT）, injection pressure （IP）, blend percentage and pecentage load were used as the input parameters for this modeling work. The ANN results show that there is a good correlation between the ANN predicted values and the experimental values for various engine performances, combustion parameters and exhaust emission characteristics. The mean square error value （MSe） is 0.005621 and the regression value ofR2 is 0.99316 for training, 0.98812 for validation, 0.9841 for testing while the overall value is 0.99173. Thus the developed ANN model is fairly powerful for predicting the performance, combustion and exhaust emissions of internal combustion engines.

关键词： cashew nut shell liquid (CNSL) artificialneural networks (ANN) thermal cracking mean squareerror (MSe)

Correspondence of bubble size and frother partitioning in flotation

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Journal of Central South University 2014年第6期21卷 2383-2390页

作者：张炜 Jan e.Nesset james A.Finch Mining & Mineral Resources Division Department of Business AdministrationChinalco China Copper Corporation Limited Department of Mining and Materials engineering McGill UniversityMontrealQCH3A 0C5Canada

The size of bubbles created in the flotation process is of great importance to the efficiency of the mineral separation ***,it is believed that frother transport between phases is perhaps the most important reason for the interactive nature of the phenomena occurring in the bulk and froth phases in flotation,as frother adsorbed in the surface of rising bubbles is removed from the bulk phase and then released into the froth as a fraction of the bubbles *** causes the increased concentration in the froth compared to the bulk concentration,named as frother *** reflects the adsorption of frother on bubbles and how to influence bubble size is not *** currently exists no such a topic aiming to link these two key *** fill this vacancy,the correspondence between bubble size and frother partitioning was *** size was measured by sampling-for-imaging(SFI)*** total organic carbon(TOC)analysis to measure the frother partitioning between froth and bulk phases was *** have shown,with no exceptions including four different frothers,higher frother concentration is in the bulk than in the *** results also show strong partitioning giving an increase in bubble size which implies there is a compelling relationship between these two,represented by CFroth/CBulk and *** CFroth/CBulkand D32 curves show similar exponential decay relationships as a function of added frother in the system,strongly suggesting that the frother concentration gradient between the bulk solution and the bubble interface is the driving force contributing to bubble size reduction.

关键词： flotation frother bubble size frother partitioning total organic carbon (TOC) analysis concentration gradient

A novel approach to prevent bubble coalescence during measurement of bubble size in flotation

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Journal of Central South University 2014年第1期21卷 338-343页

作者：张炜 Jan e.Nesset james A.Finch Mining and Mineral Resources Division Department of Business AdministrationChinalco China Copper Corporation Limited Department of Mining and Materials engineering McGill University

effect of frothers in preventing bubble coalescence during flotation of minerals has long been *** evaluate the performance of a frother,an apparatus to measure the bubble size is a basic *** Bubble Size Analyzer(MBSA) or bubble viewer that has been developed and completed by McGill University's Mineral Processing Group during the last decade is a unique instrument to serve this *** parameters which are thought to influence the bubble size measurements by McGill bubble viewer include water quality and frother concentration in the *** show that there is no difference in Sauter mean(D32) when tap or de-ionized water was used instead of process ***,the frother concentration,in this research DowFroth 250(DF250),inside the chamber exhibited a pronounced effect on bubble *** concentration below a certain point can not prevent coalescence inside the chamber and therefore caution must be taken in plant *** was also noted that the frother concentration which has been so far practiced in plant measurements(CCC75-CCC95) is high enough to prevent coalescence with the bubble viewer.

关键词： flotation frother bubble size bubble coalescence

Bubble size as a function of some situational variables in mechanical flotation machines

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Journal of Central South University 2014年第2期21卷 720-727页

The specific results of the work investigating the effect of gas density and water temperature on bubble size were *** were surrogate variables designed to investigate the effect of viscosity(varying water temperature) and altitude(varying gas density).The results show that there is a measurable but relatively small effect of gas density on bubble *** D32 is revealed to increase proportionally as(ρ0/ρg)*** projected impact on flotation kinetics at 4500 m versus sea level is small,of the order of 0.5% recovery loss for a bank of eight flotation *** effect of water temperature(4-40 °C) on bubble size is more significant than gas *** relationship correlates with water viscosity values quite closely.A finding that D32 increases proportionally as(μ/μ20)0.776 highlights the importance of accounting for viscosity effects if,for example,large process temperature fluctuations or deviation from design/test conditions are expected.

关键词： flotation frother bubble size viscosity altitude

Olfactory Dysfunction as an early Biomarker in Parkinson's Disease

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Neuroscience Bulletin 2017年第5期33卷 515-525页

作者： Michelle e.Fullard james F.Morley John e.Duda Parkinson's Disease Research Education and Clinical Center Corporal Michael J. Crescenz VA Medical CenterPhiladelphia PA 19104 USA Department of Neurology University of Pennsylvania School of Medicine Philadelphia PA 19104 USA

Olfactory dysfunction is common in Parkinson＇s disease （PD） and often predates the diagnosis by years, reflecting early deposition of Lewy pathology, the histo- logic hallmark of PD, in the olfactory bulb. Clinical tests are available that allow for the rapid characterization of olfactory dysfunction, including tests of odor identification, discrimination, detection, and recognition thresholds, memory, and tests assessing the build-up of odor intensity across increasing suprathreshold stimulus concentrations. The high prevalence of olfactory impairment, along with the ease and low cost of assessment, has fostered great interest in olfaction as a potential biomarker for PD. Hyposmia may help differentiate PD from other causes of parkinsonism, and may also aid in the identification of ＂pre-motor＂ PD due to the early pathologic involvement of olfactory pathways. Olfactory function is also correlated with other non-motor features of PD and may serve as a predictor of cognitive decline. In this article, we summarize the existing literature on olfaction in PD, focusing on the potential for olfaction as a biomarker for early or differential diagnosis and prognosis.

关键词： Olfaction · Parkinson's disease · Biomarker ·Parkinsonism · Pathology

Development of Water Quality Index (WQI) model for the groundwater in Tirupur district, South India

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Chinese Journal Of Geochemistry 2013年第3期32卷 261-268页

作者： P.J.Sajil Kumar e.J.james Water Institute Karunya University

Groundwater quality of the Tiruppur district in Tamil Nadu was investigated in this study to develop a Water Quality Index (WQI) model. Hydrochemical parameters showed tremendous variation in certain location over the seasons. Ionic chemistry of groundwater suggested that textile industries and rock-water interaction are major threats to the water quality. Analysis of Na and Ca concentration indicates that direct as well as the inverse cation exchange controls the natural cation chemistry. NO3 concentration shows that the pre-monsoon samples were affected by the fertilizer usage in agricultural fields. Na-Cl type of the water was dominant throughout the study area except few locations. WQI showed that 55% of the pre-monsoon samples and the 47% of the post monsoon samples were classified as poor/very poor/unsuitable for drinking category. Leaching of the textile waste and their transport to the downstream was well observed during the post-monsoon season. The specific contribution of river Noyyal in the transport of the solutes to the discharge zones was proved by the hydrochemistry of the samples.

关键词：地下水模型水质指数印度水岩相互作用离子化学 O3浓度纺织废料化学样品

Region-specific microRNA signatures in the human epididymis

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Asian Journal of Andrology 2018年第6期20卷 539-544页

作者： james A Browne Shih-Hsing Leir Scott e eggener Ann Harris Department of Genetics and Genome Sciences Case Western Reserve UniversityClevelandOH 44106USA Human Molecular Genetics Program Lurie Children＇s Research CenterChicagoIL 60614USA Department of Pediatrics Northwestern University Feinberg School of MedicineChicagoIL 60611USA Section of Urology University of Chicago Medical CenterChicagoIL 60611USA.

The epithelium of the human epididymis maintains an appropriate luminal environment for sperm maturation that is essential for male fertility. Regional expression of small noncoding RNAs such as microRNAs contributes to segment-specific gene expression and differentiated functions. MicroRNA profiles were reported in human epididymal tissues but not specifically in the epithelial cells derived from those regions. Here, we reveal miRNA signatures of primary cultures of caput, corpus, and cauda epididymis epithelial cells and of the tissues from which they were derived. We identify 324 epithelial cell-derived microRNAs and 259 tissue-derived microRNAs in the epididymis, some of which displayed regionalized expression patterns in cells and/or tissues. Caput cell-enriched miRNAs included miR-573 and miR-155. Cauda cell-enriched miRNAs included miR-1204 and miR-770. Next, we determined the gene ontology pathways associated with in silico predicted target genes of the differentially expressed miRNAs. The effect of androgen receptor stimulation on miRNA expression was also investigated. These data show novel epithelial cell-derived miRNAs that may regulate the expression of important gene networks that are responsible for the regionalized gene expression and function of the epididymis.

关键词： caput cauda corpus human epididymis microRNA

Role of cardiovascular intervention as a bridge to liver transplantation

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World Journal of Gastroenterology 2014年第31期20卷 10651-10657页

作者： Zankhana Raval Matthew e Harinstein james D Flaherty Bluhm Cardiovascular Institute Feinberg School of Medicine of Northwestern UniversityChicago IL 60611 United States University of Pittsburgh Medical Center Heart and Vascular Institute Pittsburgh PA 15219 United States

end stage liver disease(eSLD) is associated with many specific derangements in cardiovascular physiology, which influence perioperative outcomes and may pro-foundly influence diagnostic and management strate-gies in the preoperative period. This review focuses on evidence-based diagnosis and management of coro-nary, hemodynamic and pulmonary vascular disease in this population with an emphasis on specific strategies that may provide a bridge to transplantation. Specifi-cally, we address the underlying prevalence of cardio-vascular disease states in the eSLD population, and relevant diagnostic criteria thereof. We highlight tradi-tional and non-traditional predictors of cardiovascular outcomes following liver transplant, as well as data to guide risk-factor based diagnostic strategies. We go on to discuss the alterations in cardiovascular physiology which influence positive- and negative-predictive values of standard noninvasive testing modalities in the eSLD population, and review the data regarding the safetyand efficacy of invasive testing in the face of eSLD and its co-morbidities. Finally, based upon the totality of available data, we outline an evidence-based ap-proach for the management of ischemia, heart failure and pulmonary vascular disease in this population. It is our hope that such evidence-driven strategies can be employed to more safely bridge appropriate candidates to liver transplant, and to improve their cardiovascular health and outcomes in the peri-operative period.

关键词： Perioperative management Liver transplantation Coronary heart disease Cirrhotic cardiomyopathy Heart failure Pulmonary vascular disease