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Liver-gut axis in the regulation of iron homeostasis

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World Journal of Gastroenterology 2007年第35期13卷 4737-4745页

作者： Deepak Darshan Gregory J anderson Iron Metabolism Laboratory The Queensland Institute of Medical ResearchBrisbaneAustralia

The human body requires about 1-2 mg of iron per day for its normal functioning, and dietary iron is the only source for this essential metal. Since humans do not possess a mechanism for the active excretion of iron, the amount of iron in the body is determined by the amount absorbed across the proximal small intestine and, consequently, intestinal iron absorption is a highly regulated process. In recent years, the liver has emerged as a central regulator of both iron absorption and iron release from other tissues. It achieves this by secreting a peptide hormone called hepcidin that acts on the small intestinal epithelium and other cells to limit iron delivery to the plasma. Hepcidin itself is regulated in response to various systemic stimuli including variations in body iron stores, the rate of erythropoiesis, inflammation and hypoxia, the same stimuli that have been known for many years to modulate iron absorption. This review will summarize recent findings on the role played by the liver and hepcidin in the regulation of body iron absorption.

关键词： Iron Homeostasis Intestinal iron absorption Liver Hepcidin

Laparoscopic resection of pancreatic adenocarcinoma: Dream or reality?

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World Journal of Gastroenterology 2014年第39期20卷 14255-14262页

作者： Blaire anderson Shahzeer Karmali Department of Surgery University of Alberta Edmonton Alberta T6G 2B7 Canada Center for the Advancement of Minimally Invasive Surgery Royal Alexandra Hospital Edmonton Alberta T5H 3V9 Canada

Laparoscopic pancreatic surgery is in its infancy despite initial procedures reported two decades ago. Both laparoscopic distal pancreatectomy(LDP) and laparoscopic pancreaticoduodenectomy(LPD) can be performed competently; however when minimally invasive surgical(MIS) approaches are implemented the indication is often benign or low-grade malignant pathologies. Nonetheless, LDP and LPD afford improved perioperative outcomes, similar to those observed when MIS is utilized for other purposes. This includes decreased blood loss, shorter length of hospital stay, reduced post-operative pain, and expedited time to functional recovery. What then is its role for resection of pancreatic adenocarcinoma? The biology of this aggressive cancer and the inherent challenge of pancreatic surgery have slowed MIS progress in this field. In general, the overall quality of evidence is low with a lack of randomized control trials, a preponderance of uncontrolled series, short follow-up intervals, and small sample sizes in the studies available. Available evidence compiles heterogeneous pathologic diagnoses and is limited by case-by-case follow-up, which makes extrapolation of results difficult. Nonetheless, shortterm surrogate markers of oncologic success, such as margin status and lymph node harvest, are comparable to open procedures. Unfortunately disease recurrence and long-term survival data are lacking. In this review we explore the evidence available regarding laparoscopic resection of pancreatic adenocarcinoma, a promising approach for future widespread application.

关键词： Laparoscopic surgery Pancreatic cancer Laparoscopic distal pancreatectomy Laparoscopic pancreaticoduodenectomy Adenocarcinoma

How We Will Discover Sentience in AI

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Journal of Social Computing 2023年第3期4卷 181-192页

作者： Marc M.anderson the LORIA UMR 7503Universitéde LorraineInria the CNRS Vandoeuvre-lès-Nancy 54506France

This paper explores the question of how we can know if Artificial Intelligence(AI)systems have become or are becoming *** an overview of some arguments regarding AI sentience,it proceeds to an outline of the notion of negation in the philosophy of Josiah Royce,which is then applied to the arguments already ***’s notion of the primitive dyadic and symmetric negation relation is shown to bypass such *** negation relation and its expansion into higher types of order are then considered with regard to how,in small variations of active negation,they would disclose sentience in AI ***,I argue that the much-hyped arguments and apocalyptic speculations regarding Artificial General Intelligence(AGI)takeover and similar scenarios,abetted by the notion of unlimited data,are based on a fundamental misunderstanding of how entities engage their ***,limitation,proceeding from the symmetric negation relation,expands outward into higher types of order in polyadic relations,wherein the entity self-limits and creatively moves toward uniqueness.

关键词： artificial intelligence sentience consciousness negation Josiah Royce logic Artificial General Intelligence(AGI)

Lim kinase,a bi-functional effector in injury-induced structural plasticity of synapses

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Neural Regeneration Research 2016年第7期11卷 1029-1032页

作者： Weiwei Wang Ellen Townes-anderson Department of Pharmacology Physiology and NeuroscienceNew Jersey Medical SchoolGraduate School of Biomedical SciencesRutgers Biomedical and Health SciencesRutgersThe State University of New Jersey

The structural plasticity of synaptic terminals contributes to normal nervous system function but also to neural degeneration, in the form of terminal retraction, and regeneration, due to process growth. Synaptic morphological change is mediated through the actin cytoskeleton, which is enriched in axonal and dendritic terminals. Whereas the three RhoGTPases, RhoA, Cdc42 and Rac, function as upstream signaling nodes sensitive to extracellular stimuli, LIMK-cofilin activity serves as a common downstream effector to up-regulate actin turnover, which is necessary for both polymerization and depolymerization. The dual effects of LIMK activity make LIMK a potential target of therapeutic intervention for iniury-induced synaptic plasticity, as LIMK inhibition can stabilize actin cytoskeleton and preserve existing structure. This therapeutic benefit of LIMK inhibition has been demonstrated in animal models of injury-induced axon retraction and neuritic sprouting by rod photoreceptors. A better understanding of the regulation of LIMK-cofilin activity and the interaction with the microtubular cytoskeleton may open new ways to promote synaptic regeneration that can benefit neuronal degenerative disease.

关键词： LIMK cofilin RhoGTPases actin turnover structural plasticity synaptic degeneration andregeneration

Investigation of Pain Mechanisms by Calcium Imaging Approaches

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Neuroscience Bulletin 2018年第1期34卷 194-199页

作者： Michael anderson Qin Zheng Xinzhong Dong The Solomon H.Snyder Department of Neuroscience Center for Sensory Biology School of Medicine Johns Hopkins University Howard Hughes Medical Institute School of Medicine Johns Hopkins University

Due to the complex circuitry and plethora of cell types involved in somatosensation, it is becoming increasingly important to be able to observe cellular activity at the population level. In addition, since cells rely on an intricate variety of extracellular factors, it is important to strive to maintain the physiological environment. Many electrophysiological techniques require the implementation of artificially-produced physiological environments and it can be difficult to assess the activity of many cells simultane- ously. Moreover, imaging Ca^2＋ transients using Ca^2＋- sensitive dyes often requires in vitro preparations or in vivo injections, which can lead to variable expression levels. With the development of more sensitive geneticallyencoded Ca^2＋ indicators （GECIs） it is now possible to observe changes in Ca^2＋ transients in large populations of cells at the same time. Recently, groups have used a GECI called GCaMP to address fundamental questions in somatosensation. Researchers can now induce GCaMP expression in the mouse genome using viral or gene knock- in approaches and observe the activity of populations of cells in the pain pathway such as dorsal root ganglia （DRG）, spinal neurons, or glia. This approach can be used in vivo and thus maintains the organism＇s biological integrity. The implementation of GCaMP imaging has led to many advances in our understanding of somatosensation. Here, we review the current findings in pain research using GCaMP imaging as well as discussing potential method- ological considerations.

关键词： DRG Spinal cord GCaMP imaging Pain pathways Neural circuit

Data-Driven Earthquake Multi-impact Modeling:A Comparison of Models

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International Journal of Disaster Risk Science 2024年第3期15卷 421-433页

作者： Hamish Patten Max anderson Loake David Steinsaltz Information Management International Federation of Red Cross and Red Crescent Societies(IFRC)1211GenevaSwitzerland Department of Statistics University of OxfordOxfordOX13LBUK

In this study,a broad range of supervised machine learning and parametric statistical,geospatial,and non-geospatial models were applied to model both aggregated observed impact estimate data and satellite image-derived geolocated building damage data for earthquakes,via regression-and classification-based models,*** the aggregated observational data,models were ranked via predictive performance of mortality,population displacement,building damage,and building destruction for 375 observations across 161 earthquakes in 61 *** the satellite image-derived data,models were ranked via classification performance(damaged/unaff ected)of 369,813 geolocated buildings for 26 earthquakes in 15 *** k-fold,3-repeat cross validation was used to ensure out-of-sample predictive *** importance of several variables used as proxies for vulnerability to disasters indicates covariate *** 2023 Türkiye-Syria earthquake event was used to explore model limitations for extreme ***,applying the AdaBoost model on the 27,032 held-out buildings of the 2023 Türkiye-Syria earthquake event,predictions had an AUC of ***,without any geospatial,building-specific,or direct satellite image information,this model accurately classified building damage,with significantly improved performance over satellite image trained models found in the literature.

关键词： Disaster risk modeling Earthquake impact models Machine learning Disaster statistics Satellite image-derived buildingdamage

Within-day travel speed pattern unsupervised classification——A data driven case study of the State of Alabama during the COVID-19 pandemic

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Journal of Traffic and Transportation Engineering(English Edition) 2021年第2期8卷 170-185页

作者： Niloufar Shirani-bidabadi Rui Ma Michael anderson Connecticut Transportation Institute University of ConnecticutStorrs-MansfieldCT 06269USA Department of Civil and Environmental Engineering University of Alabama in HuntsvilleHuntsuilleAL 35899USA

Recent comparative studies on mobility patterns are emerging to describe the changes in mobility patterns due to the COVID-19 *** of the current studies utilize travel volume per day as the critical indicator and identify the impacted period by the dates of governmental lockdown or stay-at-home orders,which however may not accurately present the actual impacted *** objective of this study is to provide an alternative perspective to identify the normal and pandemic-influenced daily traffic *** of only using traffic volumes per day or assuming the impacted travel pattern began with the stay-at-home order,the methodology in this study investigates the within-day timedependent travel speed as time series,and then applies dynamic time warping algorithm and hierarchical clustering unsupervised classification methods to classify days into various groups without assuming a start date for any *** the state-wide travel speed data in Alabama,these study measures dissimilarities among within-day travel speed time *** incorporating the dissimilarities/distance matrix,various agglomerative hierarchical clustering(AHC)methods(average,complete,Ward’s)are tested to conduct proper unsupervised *** Ward’s AHC classification results show that within-day travel speed pattern in Alabama shifted more than two weeks before the issuance of the State stay-at-home *** results further show that a new travel speed pattern appears at the end of stay-at-home order,which is different from either the normal pattern before the pandemic or the initial pandemic-influenced pattern,which leads to a conclusion that a’new normal’within-day travel pattern emerges.

关键词： COVID-19 Within-day traffic dynamics Dynamic time warping Hierarchical clustering Unsupervised classification

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Automated pebble mosaic stylization of images

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Computational Visual Media 2019年第1期5卷 33-44页

作者： Lars Doyle Forest anderson Ehren Choy David Mould Carleton University

Digital mosaics have usually used regular tiles, simulating historical tessellated mosaics. In this paper, we present a method for synthesizing pebble mosaics, a historical mosaic style in which the tiles are rounded pebbles. We address both the tiling problem,of distributing pebbles over the image plane so as to approximate the input image content, and the problem of geometry, creating a smooth rounded shape for each pebble. We adopt simple linear iterative clustering(SLIC)to obtain elongated tiles conforming to image content,and smooth the resulting irregular shapes into shapes resembling pebble cross-sections. Then, we create an interior and exterior contour for each pebble and solve a Laplace equation over the region between them to obtain height-field geometry. The resulting pebble set approximates the input image while representing full geometry that can be rendered and textured for a highly detailed representation of a pebble mosaic.

关键词： non-photorealistic rendering digital mosaics image stylization segmentation image processing

Autonomous machine learning for early bot detection in the internet of things

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Digital Communications and Networks 2023年第6期9卷 1301-1309页

作者： Alex Medeiros Araujo anderson Bergamini de Neira Michele Nogueira Department of Informatics Federal University of Parana(UFPR)CuritibaBrazil Department of Computer Science Federal University of Minas Gerais(UFMG)Belo HorizonteBrazil

The high costs incurred due to attacks and the increasing number of different devices in the Internet of Things(IoT)highlight the necessity of the early detection of botnets(i.e.,a network of infected devices)to gain an advantage against ***,early botnet detection is challenging because of continuous malware mutations,the adoption of sophisticated obfuscation techniques,and the massive volume of *** literature addresses botnet detection by modeling the behavior of malware spread,the classification of malicious traffic,and the analysis of traffic *** article details ANTE,a system for ANTicipating botnEt signals based on machine learning *** system adapts itself to different scenarios and detects different types of *** autonomously selects the most appropriate Machine Learning(ML)pipeline for each botnet and improves the classification before an attack effectively *** system evaluation follows trace-driven experiments and compares ANTE results to other relevant results from the literature over four representative datasets:ISOT HTTP Botnet,CTU-13,CICDDoS2019,and *** show an average detection accuracy of 99.06%and an average bot detection precision of 100%.

关键词： Network security Bot early detection Autonomous machine learning Network traffic analysis