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The turbidite-contourite-tidalite-baroclinite-hybridite problem: orthodoxy vs. empirical evidence behind the “bouma sequence”

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Journal of Palaeogeography 2021年第2期10卷 125-156页

作者： g.shanmugam Department of Earth and Environmental sciences The University of Texas at ArlingtonTX 76019USA

The underpinning problems of deep-water facies still remain unresolved.(1) The Tb, Tc, and Td divisions of the turbidite facies model, with traction structures, are an integral part of the "bouma sequence"(Ta, Tb, Tc, Td, Te).However, deposits of thermohaline contour currents, wind-driven bottom currents, deep-marine tidal currents, and baroclinic currents(internal waves and tides) also develop discrete rippled units, mimicking Tc.(2) The application of "cut-out" logic of sequences, which was originally introduced for the "bouma sequence", with sharp basal contacts and sandy divisions containing well-developed traction structures, to muddy contorts with gradational basal contacts and an absence of well-developed traction structures is incongruent.(3) The presence of five internal divisions and hiatus in the muddy contoured facies model is in dispute.(4) Intersection of along slope contour currents with down slope sediment-gravity flows, triggering hybrid flows, also develops traction structures.(5) The comparison of genuine hybrid flows with down slope flow transformation of gravity flows is inconsistent with etymology of the term "hybrid".(6) A reexamination of the Annot sandstone at the Peira Cava type locality in sE France fails to validate either the orthodoxy of five internal divisions of the "bouma sequence" or their origin by turbidity currents. For example, the "Ta" division is composed of amalgamated units with inverse grading and floating mudstone clasts, suggesting a mass-transport deposit(MTD). The "Tb" and "Tc" divisions are composed of double mud layers and sigmoidal cross bedding, respectively, which suggest a tidalite origin.(7) Although it was reasonable to introduce a simplistic "bouma sequence" in 1962, at a time of limited knowledge on deep-water processes, it is obsolete now in 2021 to apply this model to the rock record amid a wealth of new knowledge.(8)The disconnect between 12 observed, but questionable, modern turbidity currents and over 10,

关键词： Turbidity currents Contour currents Tidal currents Internal waves and tides Hybrid flows The bouma sequence bCRs(i.e. bottom-current reworked sands)

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Watershed-based Image segmentation with Region Merging and Edge Detection

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High Technology Letters 2003年第1期9卷 58-63页

作者： salman n H Institute of Image Processing Pattern Recognition shanghai Jiaotong University Shanghai P. R. China 200030

The clustering technique is used to examine each pixel in the image which assigned to one of the clusters depending on the minimum distance to obtain primary classified image into different intensity regions. A watershed transformation technique is then employes. This includes: gradient of the classified image, dividing the image into markers, checking the Marker Image to see if it has zero points (watershed lines). The watershed lines are then deleted in the Marker Image created by watershed algorithm. A Region Adjacency graph (RAg) and Region Adjacency boundary (RAb) are created between two regions from Marker Image. Finally region merging is done according to region average intensity and two edge strengths (T1, T2). The approach of the authors is tested on remote sensing and brain MR medical images. The final segmentation result is one closed boundary per actual region in the image.

关键词： image segmentation edge detection watershed K-means edge strength brain images remote sensing images region adjacency graph (RAg).

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Prevention of DnA re-replication in eukaryotic cells

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Journal of Molecular Cell biology 2011年第1期3卷 13-22页

作者： Lan n.Truong Xiaohua Wu Department of Molecular and Experimental Medicine The Scripps Research InstituteLa JollaCA 92037USA

DnA replication is a highly regulated process involving a number of licensing and replication factors that function in a carefully orchestrated manner to faithfully replicate DnA during every cell *** of proper licensing control leads to deregulated DnA replication including DnA re-replication,which can cause genome instability and *** organisms have established several conserved mechanisms to prevent DnA re-replication and to counteract its potentially harmful *** mechanisms include tightly controlled regulation of licensing factors and activation of cell cycle and DnA damage *** licensing control and its associated compromised checkpoints have both been observed in tumor cells,indicating that proper functioning of these pathways is essential for maintaining genome *** this review,we discuss the regulatory mechanisms of licensing control,the deleterious consequences when both licensing and checkpoints are compromised,and present possible mechanisms to prevent re-replication in order to maintain genome stability.

关键词： DnA re-replication cell cycle checkpoints DnA damage response Cdt1 Dsb repair genome stability tumorigenesis

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Artificial intelligence in gastroenterology: A state-of-the-art review

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World Journal of gastroenterology 2021年第40期27卷 6794-6824页

作者： Paul T Kröner Megan ML Engels benjamin s glicksberg Kipp W Johnson Obaie Mzaik Jeanin E van Hooft Michael b Wallace Hashem b El-serag Chayakrit Krittanawong Division of gastroenterology and Hepatology Mayo ClinicJacksonvilleFL 32224United States Cancer Center Amsterdam Department of Gastroenterology and HepatologyAmsterdam UMCLocation AMCAmsterdam 1105The Netherlands The Hasso Plattner Institute for Digital Health Icahn School of Medicine at Mount SinaiNew YorkNY 10029United States Department of gastroenterology and Hepatology Leiden University Medical CenterAmsterdam 2300The Netherlands Division of gastroenterology and Hepatology Sheikh Shakhbout Medical CityAbu Dhabi 11001United Arab Emirates section of gastroenterology and Hepatology Michael E.DeBakey VA Medical Center and Baylor College of MedicineHoustonTX 77030United States section of Health services Research Michael E.DeBakey VA Medical Center and Baylor College of MedicineHoustonTX 77030United States section of Cardiology Michael E.DeBakey VA Medical CenterHoustonTX 77030United States

The development of artificial intelligence(AI)has increased dramatically in the last 20 years,with clinical applications progressively being explored for most of the medical *** field of gastroenterology and hepatology,substantially reliant on vast amounts of imaging studies,is not an *** clinical applications of AI systems in this field include the identification of premalignant or malignant lesions(e.g.,identification of dysplasia or esophageal adenocarcinoma in barrett’s esophagus,pancreatic malignancies),detection of lesions(e.g.,polyp identification and classification,small-bowel bleeding lesion on capsule endoscopy,pancreatic cystic lesions),development of objective scoring systems for risk stratification,predicting disease prognosis or treatment response[e.g.,determining survival in patients post-resection of hepatocellular carcinoma),determining which patients with inflammatory bowel disease(IbD)will benefit from biologic therapy],or evaluation of metrics such as bowel preparation score or quality of endoscopic *** objective of this comprehensive review is to analyze the available AI-related studies pertaining to the entirety of the gastrointestinal tract,including the upper,middle and lower tracts;IbD;the hepatobiliary system;and the pancreas,discussing the findings and clinical applications,as well as outlining the current limitations and future directions in this field.

关键词： Artificial intelligence Machine learning Deep learning Clinical applications gastroenterology

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The effectiveness of eyespots and masquerade in protecting artificial prey across ontogenetic and seasonal shifts

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Current Zoology 2022年第4期68卷 451-458页

作者： Elizabeth g Postema Department of Entomology and nematology University of CaliforniaDavisCA 95616USA

When constraints on antipredator coloration shift over the course of development,it can be advantageous for animals to adopt different color strategies for each life *** caterpillars in the genus Papilio exhibit unique ontogenetic color sequences:for example,early instars that masquerade as bird feces,with later instars possessing eyespots.I hypothesize that larvae abandon feces masquerade in favor of eyespots due to ontogenetic changes in signaler *** ontogenetic pattern also occurs within broader seasonal shifts in background color and predator activity.I conducted predation experiments with artificial prey to determine how potential signaling constraints(specifically size and season)shape predation risk,and consequently the expression of ontogenetic color change in Papilio ***,both predation and background greenness declined significantly from July to september,though there was little evidence that these patterns impacted the effectiveness of either color *** size and color strongly affected the attack rate of avian predators:attacks increased with prey size regardless of color,and eyespotted prey were attacked more than masquerading prey *** results may reflect a key size-mediated tradeoff between conspicuousness and intimidation in eyespotted prey,and raise questions about how interwoven aspects of behavior and signal environment might maintain the prevalence of large,eyespotted larvae in nature.

关键词： ontogenetic color change eyespots masquerade predator-prey dynamics season

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Role of innate immunity in the development of hepatocellular carcinoma

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World Journal of gastroenterology 2013年第43期19卷 7500-7514页

作者： Rajagopal n Aravalli Department of Radiology University of Minnesota Medical SchoolMinneapolisMN 55455United States

Hepatocellular carcinoma(HCC)is the most common form of liver cancer *** is caused by a variety of risk factors,most common ones being infection with hepatitis viruses,alcohol,and *** often develops in the background of underlying cirrhosis,and even though a number of interventional treatment methods are currently in use,recurrence is fairly common among patients who have had a ***,whole liver transplantation remains the most practical treatment option for *** to the growing incidence of HCC,intense research efforts are being made to understand cellular and molecular mechanisms of the disease so that novel therapeutic strategies can be developed to combat liver *** recent years,it has become clear that innate immunity plays a critical role in the development of a number of liver diseases,including *** particular,the activation of Toll-like receptor signaling results in the generation of immune responses that often results in the production of proinflammatory cytokines and chemokines,and could cause acute inflammation in the *** this review,the current knowledge on the role of innate immune responses in the development and progression of HCC is examined,and emerging therapeutic strategies based on molecular mechanisms of HCC are discussed.

关键词： Hepatocellular carcinoma Innate immunity Toll-like receptor Liver cancer Inflammation

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small cell lung carcinoma metastatic to the stomach: Commonly overlooked, limited treatment options

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World Journal of gastroenterology 2024年第48期30卷 5198-5204页

作者： Terence n Moyana Diagnostic and Molecular Pathology The Ottawa Hospital and University of OttawaOttawa K1H 8L6OntarioCanada

small cell lung carcinoma metastatic to the stomach,whether synchronous or metachronous,is a rare phenomenon accounting for<0.5%of lung *** it can be overlooked by clinicians resulting in delayed *** manuscript commen... 详细信息

small cell lung carcinoma metastatic to the stomach,whether synchronous or metachronous,is a rare phenomenon accounting forng *** it can be overlooked by clinicians resulting in delayed *** manuscript comments on Yang et al’s article which reported 3 such *** main diagnostic features are based on routine morphology comprised of small cells with hyperchromatic nuclei,scant cytoplasm,brisk mitoses and *** can be supplemented by immunohistochemistry demonstrating positivity for cytokeratin,thyroid transcription factor-1 and neuroendocrine markers as well as a high Ki-67 labelling *** modalities such as positron emission tomography/contrast computed tomography help to confirm lung origin and rule out the possibility of extra-pulmonary small cell *** predominant mechanism of spread is most likely *** is generally poor since this represents stage 4 disease but survival can be improved by chemo/ra-diotherapy and palliative surgery in select *** outcomes have not changed much in the last several decades,the recent Food and Drug Adminis-tration approval of immune checkpoint inhibitors was a significant milestone as was the delineation of small cell lung carcinoma molecular *** biopsies are increasingly being used for biomarker studies in clinical trials to assess treatment response and prognosis.

关键词： gastric metastasis small cell lung carcinoma Histopathology Immuno-histochemistry Positron emission tomography/contrast computed tomography Chemo-radiotherapy Immunotherapy surgery biomarkers Clinical trials

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Analysis of heat transfer processes for sapphire growth by horizontal directed crystallization method

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Journal of Advanced Dielectrics 2020年第1期10卷 2-8页

作者： Yu.V.Klunnikova s.P.Malyukov A.V.Filimonov n.Zhang Institute of nanotechnology Electronics and Electronic Equipment Engineering southern Federal University shevchenko 2Taganrog 347928Russia Department of Physical Electronics Peter the great st.Petersburg Polytechnic University st.Petersburg 195251 Politekhnicheskaya 29Russia Electronic Materials Research Laboratory Xi’an Jiaotong University 710049

This research summarizes the analytical and experimental results of heat-transfer processes influence on defects formation during sapphire crystal growth by horizontal directed crystallization method(HDC).The shape of solid-melt interface significantly influences the process of sapphire crystals growth by this *** receive the stefan problem solution for sapphire crystals *** allows investigating the crystal growth process and the related factors(thermal stresses on different stages of growth process),their influence on defects *** investigate the main reasons for the formation of defective structures of the solid phase of sapphire crystals and the influence of thermal unit construction,the crystal geometry on the quality of the resulting sapphire *** study the structure formation process,impurity distribution,and the nature of the defects in the crystal during it growth.

关键词： Crystal growth directional crystallization defects internal stresses analytical methods

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A Comparative study on the structural and Vibrational Properties of Two Potential Antimicrobial and Anticancer Cyanopyridine Derivatives

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Open Journal of synthesis Theory and Applications 2015年第1期4卷 1-19页

作者： María J. Márquez María b. Márquez Pablo g. Cataldo silvia A. brandán Cátedra de Química general Instituto de Química Inorgánica Facultad de Bioquímica Química y Farmacia Universidad Nacional de Tucumán Tucumán Argentina

2-Hydroxy-4,6-dimethylpyridine-3-carbonitrile and 2-chloro-4,6-dimethylpyridine-3-carbonitrile compounds have been studied from a theoretical point of view in order to know their structural and vibrational properties in gas and aqueous solution phases by means of Density Functional Theory (DFT) calculations. The stable structures in both media were optimized by using the hybrid b3LYP/6-31g* method and the solvent effects in aqueous solution were studied by using the integral equation formalism of the polarizable continuum model (IEFPCM) employing the selfconsistent reaction field (sCRF) method. Detailed vibrational analyses for both compounds in the two phases were performed combining the DFT calculations with Pulay’s scaled Quantum Mechanics Force Field (sQMFF) methodology. The different interactions for both compounds were analyzed by means of the bond orders, atomic charges, solvation energies, dipole moments, molecular electrostatic potentials and force constants parameters. The nature of the interactions was studied by using different descriptors.

关键词： Cyanopyridine Vibrational spectra Molecular structure Force Field DFT Calculations

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Environmental Compensation Actions in Costa Rica: Disparity between Commitments and Actions

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Open Journal of Ecology 2022年第5期12卷 287-305页

作者： Fabián bonilla-Murillo Juan s. Monrós Mahmood sasa Marín Clodomiro Picado Institute University of Costa Rica San José Costa Rica Research Center for biodiversity and Tropical Ecology University of Costa Rica & Biology School University of Costa Rica San José Costa Rica Cavanilles Institute of biodiversity and Evolutive biology University of Valencia Valencia Espa&#241 a

Introduction: Environmental compensation is a legal-administrative instrument used by agencies that supervise the environmental impact assessment (EIA) to offset irreversible impacts generated by development projects. The compensation is usually framed in the principle of ecological equivalence, which seeks to equate the losses due to the impact with a net environmental gain obtained by the compensatory actions. Methods: We analyzed the records of development projects that have merited an environmental compensation plan registered by the national Environmental Technical secretariat of Costa Rica (sETEnA) between January 2018 and June 2020. Results: seventy-four projects were analyzed;just over 75% of them corresponded to infrastructure projects while the rest concerned exploitation activities of materials and resources. The main impacts that elicited compensation plans were: deforestation and destruction of riverbanks (13%), earthworks (15.5%), poor water management (15.5%), and administrative faults or non-compliance with environmental commitments (62%). The main compensatory measures conducted were: building school infrastructure (20% of the projects), support for environmental education programs (17%), and reforestation programs (>15%), although actions such as the purchase of school supplies, donation of equipment to local communities and the arrangement of roads and causeways were also recorded. In only three projects, the replacement of the impacted habitat was used as compensation for projected damage. Discussion: The registered compensatory measures do not endorse the spirit of return on components equivalent to those impacted that generate a net environmental gain and respond only to impacts that had not been considered during the preliminary evaluation of the project. The compensation plan used in Costa Rica is a sanctioning instrument based on economic valuation and does not guarantee a return equivalent to environmental losses. Therefore, compensation mu

关键词： Environmental Compensation Impacts Environment Environmental Evaluation

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