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Three-stage Transfer Learning with AlexNet50 for MRI Image Multi-Class Classification with Optimal Learning Rate

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Computer Modeling in Engineering & sciences 2025年第1期142卷 155-183页

作者： suganya Athisayamani A.robert singh Gyanendra Prasad Joshi Woong Cho school of Computing Sastra Deemed to be UniversityThanjavur613401India Department of Computational Intelligence SRM Institute of Science and TechnologyKattankulathur603203India Department of AI and software Engineering Kangwon National UniversitySamcheok25913Republic of Korea Department of Electronics Information and Communication EngineeringKangwon National UniversitySamcheok25913Republic of Korea

In radiology,magnetic resonance imaging(MRI)is an essential diagnostic tool that provides detailed images of a patient’s anatomical and physiological *** is particularly effective for detecting soft tissue ***,radiologists manually interpret these images,which can be labor-intensive and time-consuming due to the vast amount of *** address this challenge,machine learning,and deep learning approaches can be utilized to improve the accuracy and efficiency of anomaly detection in MRI *** manuscript presents the use of the Deep AlexNet50 model for MRI classification with discriminative learning *** are three stages for learning;in the first stage,the whole dataset is used to learn the *** the second stage,some layers of AlexNet50 are frozen with an augmented dataset,and in the third stage,AlexNet50 with an augmented dataset with the augmented *** method used three publicly available MRI classification datasets:Harvard whole brain atlas(HWBA-dataset),the school of Biomedical Engineering of southern Medical University(sMU-dataset),and The National Institute of Neuroscience and Hospitals brain MRI dataset(NINs-dataset)for *** hyperparameter optimizers like Adam,stochastic gradient descent(sGD),Root mean square propagation(RMs prop),Adamax,and AdamW have been used to compare the performance of the learning ***-dataset registers maximum classification *** evaluated the performance of the proposed classification model using several quantitative metrics,achieving an average accuracy of 98%.

关键词： MRI tumors classification AlexNet50 transfer learning hyperparameter tuning optimizer

The missing hydrogen ion,part-1:Historical precedents *** concepts

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sports Medicine and Health science 2023年第4期5卷 336-343页

作者： robert Robergs Bridgette O'Malley sam Torrens Jason siegler school of Exercise and Nutrition sciences Queensland University of TechnologyKelvin GroveQueensland4059Australia AsU Health Futures Center College of Health SolutionsArizona State University6161 East Mayo BlvdPhoenix85054ArizonaUSA

The purpose of this review and commentary was to provide an historical and evidence-based account of organic acids and the biochemical and organic chemistry evidence for why cells do not produce metabolites that are *** scientific study of acids has a long history dating to the 16th and 17th centuries,and the definition of an acid was proposed in 1884 as a molecule that when in an aqueous solution releases a hydrogen ion(H^(+)).There are three common ionizable functional groups for molecules classified as acids:1)the carboxyl group,2)the phos-phoryl group and 3)the amine *** propensity by which a cation will associate or dissociate with a negatively charged atom is quantified by the equilibrium constant(K_(eq))of the dissociation constant(K_(d))of the ionization(K_(eq)=K_(d)),which for lactic acid(HLa)***(La^(-))is expressed as:K_(eq)=K_(d)=[H^(+)][La^(-)]/[HLa]=4677.3514(ionic strength=0.01 Mol⋅L^(-1),T=25℃).The negative log10 of the dissociation pKd reveals the pH at which half of the molecules are ionized,which for HLa=***,knowing the pKd and the pH of the solution at question will reveal the extent of the ionization *** of molecules that are classified as acids.

关键词： Hydrogen ion Acid Acidosis pH Equilibrium constant(K_(eq)) Ionization Dissociation constant(K_(d))

Lipid droplets in the nervous system:involvement in cell metabolic homeostasis

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Neural Regeneration Research 2025年第3期20卷 740-750页

作者： Yuchen Zhang Yiqing Chen Cheng Zhuang Jingxuan Qi robert Chunhua Zhao Jiao Wang school of Life sciences Shanghai UniversityShanghaiChina school of Medicine Shanghai UniversityShanghaiChina Institute of Basic Medical sciences Chinese Academy of Medical sciences School of Basic MedicinePeking Union Medical CollegeBeijingChina Center of Excellence in Tissue Engineering Chinese Academy of Medical SciencesBeijingChina Beijing Key Laboratory of New Drug Development and Clinical Trial of stem Cell Therapy BeijingChina

Lipid droplets serve as primary storage organelles for neutral lipids in neurons,glial cells,and other cells in the nervous *** droplet formation begins with the synthesis of neutral lipids in the endoplasmic ***,lipid droplets were recognized for their role in maintaining lipid metabolism and energy homeostasis;however,recent research has shown that lipid droplets are highly adaptive organelles with diverse functions in the nervous *** addition to their role in regulating cell metabolism,lipid droplets play a protective role in various cellular stress ***,lipid droplets exhibit specific functions in neurons and glial *** of lipid droplet formation leads to cellular dysfunction,metabolic abnormalities,and nervous system *** review aims to provide an overview of the role of lipid droplets in the nervous system,covering topics such as biogenesis,cellular specificity,and ***,it will explore the association between lipid droplets and neurodegenerative *** the involvement of lipid droplets in cell metabolic homeostasis related to the nervous system is crucial to determine the underlying causes and in exploring potential therapeutic approaches for these diseases.

关键词： Alzheimer's disease lipid droplet biogenesis lipid droplets lipid metabolism nervous system neurodegenerative disorders oxidative stress Parkinson's disease

The missing hydrogen ion, part-2: Where the evidence leads to

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sports Medicine and Health science 2024年第1期6卷 94-100页

作者： robert Robergs Bridgette O’Malley sam Torrens Jason siegler school of Exercise and Nutrition sciences Queensland University of TechnologyKelvin GroveQueensland4059Australia AsU Health Futures Center College of Health SolutionsArizona State University6161 East Mayo BlvdPhoenix85054ArizonaUSA

The purpose of this manuscript was to present the evidence for why cells do not produce metabolic *** addition,evidence that opposes common viewpoints and arguments used to support the cellular production of lactic acid(HLa)or liver keto-acids have been *** chemistry reveals that many molecules involved in cellular energy catabolism contain functional groups classified as *** two main acidic functional groups of these molecules susceptible to-H^(+) þrelease are the carboxyl and phosphoryl structures,though the biochemistry and organic chemistry of molecules having these structures reveal they are produced in a non-acidic ionic(negatively charged)structure,thereby preventing pH dependent -H^(+)þ*** evidence from the industrial production of HLa further reveals that lactate(La)is produced followed by an acidification step that converts La to HLa due to pH dependent-H^(+)þ***,there is a plentiful list of other molecules that are classified as acids and compared to HLa have similar values for their Hþdissociation constant(pKd).For many metabolic conditions,the cumulative turnover of these molecules is far higher than for *** collective evidence documents the non-empirical basis for the construct of the cellular production of HLa,or any other metabolic acid.

关键词： Metabolic biochemistry Acidosis Carboxyl Phosphoryl Metabolic acid Dissociation Association pH

sleep as a window to understand and regulate Alzheimer's disease:emerging roles of thalamic reticular nucleus

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Neural Regeneration Research 2025年第6期20卷 1711-1712页

作者： Haoqi sun shiqian shen robert J.Thomas M.Brandon Westover Can Zhang Department of Neurology Beth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMAUSA Center for Translational Pain Research Department of AnesthesiaCritical Care and Pain MedicineMassachusetis General HospitalHarvard Medical SchoolBostonMAUSA Division of Pulmonary Critical Care and Sleep MedicineDepartment of MedicineBeth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMAUSA Genetics and Aging Research Unit McCance Center for Brain HealthMass General Institute for Neurodegenerative DiseaseDepartment of NeurologyMassachusetts General HospitalHarvard Medical SchoolBostonMAUSA

Introduction:Alzheimer 's disease(AD) is a common neurodegenerative disorder and the primary cause of dementia. Considerable evidence supports the “amyloid hypothesis,” stating that the pathogenesis of AD is primarily caused by the deposition of amyloid-β(Aβ), which drives tau phosphorylation, neuroinflammation, and neurodegeneration in the brain. The amyloid hypothesis is strengthened by the significant and moderate benefit of lecanemab, a humanized antibody through an anti-amyloid mechanism,showing slowed clinical decline(van Dyck et al.,2023). The recent positive results of anti-amyloid trials have brought back focus on the amyloid hypothesis through biochemical, genetic, and pharmacological approaches(Zhang, 2023).

关键词： Alzheimer inflammation hypothesis

High-nickel insects and nickel hyperaccumulator plants： A review

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Insect science 2009年第1期16卷 19-31页

作者： robert s. Boyd Department of Biological sciences 101 Life Sciences Building Auburn University Alabama 36849-5407 USA

Insects can vary greatly in whole-body elemental concentrations. Recent investigations of insects associated with Ni hyperaccumulator plants have identified insects with relatively elevated whole-body Ni levels. Evaluation of the limited data available indicates that a whole-body Ni concentration of 500μg Ni/g is exceptional： I propose that an insect species with a mean value of 500μg Ni/g or greater, in either larval/nymphal or adult stages, be considered a ＂high-Ni insect＂. Using the 500μg Ni/g criterion, 15 species ofhigh-Ni insects have been identified to date from studies in Mpumalanga （south Africa）, New Caledonia and California （UsA）. The highest mean Ni concentration reported is 3 500 μg Ni/g for nymphs of a south African stenoscepa species （Orthoptera： Pyrgomorphidae）. The majority of high-Ni insects （66%） are heteropteran herbivores. studies of high-Ni insect host preference indicate they are monophagous （or nearly so） on a particular Ni hyperaccumulator plant species. Much of the Ni in bodies of these insects is in their guts （up to 66%-75%）, but elevated levels have also been found in Malpighian tubules, suggesting efficient elimination as one strategy for dealing with a high-Ni diet. Tissue levels of Ni are generally much lower than gut concentrations, but up to 1200μg Ni/g has been reported from exuviae, suggesting that molting may be another pathway of Ni elimination. One ecological function of the high Ni concentration of these insects may be to defend them against natural enemies, but to date only one experimental test has supported this ＂elemental defense＂ hypothesis. Community-level studies indicate that high-Ni insects mobilize Ni into food webs but that bioaccumulation of Ni does not occur at either plant-herbivore or herbivorepredator steps. Unsurprisingly, Ni bioaccumulation indices are greater for high-Ni insects compared to other insect species that feed on Ni hyperaccumulator plants. There is some evidence of Ni mobilization into food webs

关键词： bioaccumulation elemental defense heavy metals herbivore defense,hyperaccumulation metal tolerance nickel

Lygus hesperus （Heteroptera： Miridae） tolerates high concentrations of dietary nickel

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Insect science 2007年第3期14卷 201-205页

作者： robert s. BOYD Department of Biological sciences Auburn University Alabama USA

Nickel hyperaccumulator plants contain unusually elevated levels of Ni （〉 1 000 μg Ni/g）. some insect herbivores, including Lygus hesperus （Western tarnished plant bug）, have been observed feeding on the California Ni hyperaccumulator streptanthus polygaloides. This bug may be able to utilize s. polygaloides as a host either through its feeding behavior or by physiological tolerance of Ni. This experiment determined the Ni tolerance of L hesperus by offering insects artificial diet amended with 0, 0.4, 1, 2, 4.5, 10, 20 and 40 mmol Ni/L and recording survival. survival varied due to Ni concentration, with diets containing 10 mmol Ni/L and greater resulting in significantly lower survival compared to the control （0 mmol Ni/L） treatment. Insects tolerated diet containing as much as 4.5 mmol Ni/L, a relatively elevated Ni concentration. I conclude that L hesperus can feed on s. polygaloides because it is Ni-tolerant, probably due to physiological mechanisms that provide it with resistance to plant chemical defenses including elemental defenses such as hyperaccumulated Ni.

关键词： elemental defense heavy metals herbivore defense hyperaccumulation metal tolerance nickel

Back-to-Front Ordering of Triangles in Digital Terrain Models over Regular Grids

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Journal of Computer science & Technology 2018年第6期33卷 1192-1203页

作者： Jesús Alonso robert Joan-Arinyo Informatics in Engineering Group Technical University of Catalonia 08028 Barcelona Catalonia Center for Biomedical Engineering Research Sant Joan de Ddu Research Institute 08028 Barcelona Catalonia Visualization Interaction and Virtual Reality Group Technical University of Catalonia 08028 Barcelona Catalonia

Visiting triangles that conform a digital terrain model is a core operation in a number of fields like animationand video games or generating profiles, cross-sections, and contours in civil engineering. Perfornfing the visit in an efficientmanner is an issue specially when the output of the traversal depends in some way on additional parameters or informationchanging over time, for example, a moving point of view. In this work we report a set of rules that, given a digital terrainmodel defined over a regular grid and an arbitrary point of view outside the terrain, define a total back-to-front order in theset of digital terrain model triangles with respect to the point. The set of rules is minimal, complete and correct. To assesshow the rules perform, we have implemented a CPU-based algorithm for realistically rendering height fields defined overregular grids. The algorithm does not make use of the z-buffer or shaders featured by our graphics card. We show how ouralgorithm is implemented and show visual results obtained from synthetic and real data. We further discuss the algorithmperformance with respect to two algorithms： a naive algorithm that visits triangles according to grid indices and does notsolve the hidden line problem, and the z-buffer provided by the graphics card featured by our computer. Our algorithmallows real-time interaction when the point of view arbitrarily moves in 3D space and we show that its performance is asgood as that of the z-buffer graphics card.

关键词： back-to-front ordering digital terrain model elevation terrain model triangle strip, visibility

Tectonic Implications of Paleomagnetic Results From Upper silurian series Along the Hexi Corridor, Gansu, China

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science China Chemistry 1993年第6期36卷 720-728页

作者：孟自芳 robert s. Coe Lanzhou Institute of Geology Academia Sinica Lanzhou 730000 PRC University of California at santa Cruz USA

Characteristic directions of remanent magnetization of 38 samples from Upper silurian series (Hanxia Formation) along the Hexi Corridor passed fold test at a 99% confidence level. The corresponding paleopole is located at 45.1°N, 5.5°E (A_(95)= 4.7°, κ=25.1), close to the Late Permian pole for this area (41.4°N, 358.6°E; A_(95)= 4.3°, κ=26.6). However, there appears an obvious difference between paleolatitudes for these two stages (6°±). Based on paleomagnetic data, it can be deduced that the Hexi Corridor had probably been the western extension of the North China Block by the time of Late silurian and kept being tectonically mobile compared with the principal parts of the North China Block. In addition, paleomagnetic data reveal that the Hexi Corridor experienced a southward displacement of about 600 km during the Late Paleozoic Era.

关键词： Hexi Corridor Upper silurian series southward displacement.