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design of soft magnetic materials

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npj Computational Materials 2022年第1期8卷 17-26页

作者： Ananya Renuka Balakrishna richard d.James Aerospace and Mechanical Engineering University of Southern CaliforniaLos AngelesCA90089USA Aerospace and Engineering Mechanics University of MinnesotaMinneapolisMN55455USA

We present a strategy for the design of ferromagnetic materials with exceptionally low magnetic hysteresis,quantified by *** this strategy,we use a micromagnetic algorithm that we have developed in previous research and which has been validated by its success in solving the“Permalloy Problem”—the well-known difficulty of predicting the composition 78.5%Ni of the lowest coercivity in the Fe–Ni system—and by the insight it provides into the“Coercivity Paradox”of ***,the design strategy predicts that cubic materials with large saturation magnetization ms and large magnetocrystalline anisotropy constant κ_(1) will have low coercivity on the order of that of Permalloy,as long as the magnetostriction constantsλ_(100),λ_(111)are tuned to special *** explicit prediction for a cubic material with low coercivity is the dimensionless number(c_(11)−c_(12))λ_(100)^(2)/(2_(κ_(1)))=81 for〈100〉easy *** results would seem to have broad potential application,especially to magnetic materials of interest in energy research.

关键词： magnetic cubic exceptional

“Teaching old dogs new tricks”:targeting neural extracellular matrix for normal and pathological aging-related cognitive decline

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Neural Regeneration Research 2019年第4期14卷 578-581页

作者： Adam d.richard Xiao-Hong Lu department of Pharmacology Toxicology and Neuroscience Louisiana State University Health Sciences Center

Cognitive decline is a feature of normal and pathological aging. As the proportion of the global aged population continues to grow, it is imperative to understand the molecular and cellular substrates of cognitive aging for therapeutic discovery. This review focuses on the critical role of neural extracellular matrix in the regulation of neuroplasticity underlying learning and memory in another under-investigated "critical period": the aging process. The fascinating ideas of neural extracellular matrix forming a synaptic cradle in the tetrapartite synapse and possibly serving as a substrate for storage of very long-term memories will be introduced. We emphasize the distinct functional roles of diffusive neural extracellular matrix and perineuronal nets and the advantage of the coexistence of two structures for the adaptation to the ever-changing external and internal environments. Our study of striatal neural extracellular matrix supports the idea that chondroitin sulfate proteoglycan-associated extracellular matrix is restrictive on synaptic neuroplasticity, which plays important functional and pathogenic roles in early postnatal synaptic consolidation and aging-related cognitive decline. Therefore, the chondroitin sulfate proteoglycan-associated neural extracellular matrix can be targeted for normal and pathological aging. Future studies should focus on the cell-type specificity of neural extracellular matrix to identify the endogenous, druggable targets to restore juvenile neuroplasticity and confer a therapeutic benefit to neural circuits affected by aging.

关键词： aging cognitive decline neural extracellular matrix tetrapartite synapse long-term memory storage therapeutic targeting striatum chondroitin sulfate proteoglycan

Epigenetic regulation of neuronal dendrite and dendritic spine development

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Frontiers in Biology 2010年第4期5卷 304-323页

作者： richard d.SMRT Xinyu ZHAO department of Neuroscience University of New Mexico School of MedicineAlbuquerqueNew Mexico 87131USA

dendrites and the dendritic spines of neurons play key roles in the connectivity of the brain and have been recognized as the locus of long-term synaptic plasticity,which is correlated with learning and *** development of dendrites and spines in the mammalian central nervous system is a complex process that requires specific molecular events over a period of *** has been shown that specific molecules are needed not only at the spine’s point of contact,but also at a distance,providing signals that initiate a cascade of events leading to synapse *** specific molecules that act to signal neuronal differentiation,dendritic morphology,and synaptogenesis are tightly regulated by genetic and epigenetic *** has been shown that the dendritic spine structure and distribution are altered in many diseases,including many forms of mental retardation(MR),and can also be potentiated by neuronal activities and an enriched *** dendritic spine pathologies are found in many types of MR,it has been proposed that an inability to form normal spines leads to the cognitive and motor deficits that are characteristic of *** mechanisms,including dNA methylation,chromatin remodeling,and the noncoding RNA-mediated process,have profound regulatory roles in mammalian gene *** study of epigenetics focuses on cellular effects that result in a heritable pattern of gene expression without changes to genomic *** extensive efforts to understand the molecular regulation of dendrite and spine development,epigenetic mechanisms have only recently been *** this review,we will focus on epigenetic mechanisms that regulate the development and maturation of dendrites and *** will discuss how epigenetic alterations could result in spine abnormalities that lead to MR,such as is seen in fragile X and Rett *** will also discuss both general methodology and recent technological advances in the study of neuronal den

关键词： epigenetics neurodevelopment dendritic spine synapse microRNA methyl-CpG binding protein 2(MeCP2) mental retardation

Seismic Reflection Characteristics of Naturally-Induced Subsidence Affecting Transportation

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Journal of China University of Geosciences 2009年第3期20卷 496-512页

作者： richard d Miller Jianghai Xia don W Steeples Kansas Geological Survey The University of Kansas Lawrence KS 66047 USA department of Geology The University of Kansas Lawrence KS 66047 USA

High-resolution seismic reflections have been used effectively to investigate sinkholes formed from the dissolution of a bedded salt unit found throughout most of Central Kansas. Surface subsidence can have devastating effects on transportation structures. Roads, rails, bridges, and pipelines can even be dramatically affected by minor ground instability. Areas susceptible to surface subsidence can put public safety at risk. Subsurface expressions significantly larger than surface depressions are consistently observed on seismic images recorded over sinkholes in Kansas. Until subsidence reaches the ground surface, failure appears to be controlled by compressional forces evidenced by faults with reverse orientation. Once a surface depression forms or dissolution of the salt slows or stops, subsidence structures are consistent with a tensional stress environment with prevalent normal faults. detecting areas of rapid subsidence potential, prior to surface failure, is the ultimate goal of any geotechnical survey where the ground surface is susceptible to settling. Seismic reflection images have helped correlate active subsidence to dormant paleofeatures, project horizontal growth of active sinkholes based on subsurface structures, and appraise the risk of catastrophic failure.

关键词： shallow seismic reflection imaging subsidence sinkhole.

Clinical significance of mesenteric panniculitis-like abnormalities on abdominal computerized tomography in patients with malignant neoplasms

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World Journal of Gastroenterology 2016年第48期22卷 10601-10608页

作者： Eli d Ehrenpreis Grigory Roginsky richard M Gore University of Chicago Center for the Study of Complex Diseases Gastroenterology North Shore University Health System Highland Park Hospital department of Radiology North Shore University HealthS ystem

AIM To clarify the association of malignancy with mesenteric panniculitis-like changes on computed tomography(CT).METHOdS All abdominal CT scans performed at North Shore University HealthS ystem showing mesenteric panniculitis from January 2005 to August 2010 were identified in the Radnet(Rad Net Corporation, Los Angeles, CA) database. Patients with a new or known diagnosis of a malignancy were included for this analysis. Longitudinal clinical histories were obtained from electronic medical *** In total, 147794 abdominal CT scans were performed during the study period. Three hundred and fiftynine patients had mesenteric panniculitis(MP)-like abnormalities on their abdominal CT. Of these patients, 81 patients(22.6%) had a known history of cancer at the time of their CT scan. Nineteen(5.3%) had a new diagnosis of cancer in concurrence with their CT, but the majority of these(14/19, 74%) were undergoing CT as part of a malignancy evaluation. Lymphomas were the most common cancers associated with MPlike findings on CT(36 cases, 36%), with follicular lymphoma being the most frequent subtype(17/36). A variety of solid tumors, most commonly prostate(7) and renal cell cancers(6) also were seen. CT follow up was obtained in 56 patients. Findings in the mesentery were unchanged in 45(80%), worsened in 6(11%), and improved in 5 patients(9%). Positron emission tomography(PET) scans performed in 44 patients only showed a positive uptake in the mesenteric mass in 2 patients(5%). CONCLUSION A new diagnosis of cancer is uncommon in patients with CT findings suggestive of MP. MP-like mesenteric abnormalities on CT generally remain stable in patients with associated malignancies. PET scanning is not recommended in the evaluation of patients with mesenteric panniculitis-like findings on CT.

关键词： Panniculitis Peritoneal X ray Neoplasms Computed tomography Small intestine Misty mesentery Lymphoma Tomography Positron emission tomography

Monte Carlo sampling for error propagation in linear regression and applications in isochron geochronology

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Science Bulletin 2019年第3期64卷 189-197页

作者： Yang Li Shuang Zhang richard Hobbs Camila Caiado Adam d.Sproson david Selby Alan d.Rooney State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences department of Earth Sciences Durham University department of Geology and Geophysics Yale University department of Mathematical Sciences Durham University Atmosphere and Ocean Research Institute The University of Tokyo

Geochronology is essential for understanding Earth's history. The availability of precise and accurate isotopic data is increasing; hence it is crucial to develop transparent and accessible data reduction techniques and tools to transform raw mass spectrometry data into robust chronological data. Here we present a Monte Carlo sampling approach to fully propagate uncertainties from linear regressions for isochron dating. Our new approach makes no prior assumption about the causes of variability in the derived chronological results and propagates uncertainties from both experimental measurements(analytical uncertainties) and underlying assumptions(model uncertainties) into the final age *** synthetic examples, we find that although the estimates of the slope and y-intercept(hence age and initial isotopic ratios) are comparable between the Monte Carlo method and the benchmark‘‘Isoplot" algorithm, uncertainties from the later could be underestimated by up to 60%, which are likely due to an incomplete propagation of model uncertainties. An additional advantage of the new method is its ability to integrate with geological information to yield refined chronological constraints. The new method presented here is specifically designed to fully propagate errors in geochronological applications involves linear regressions such as Rb-Sr, Sm-Nd, Re-Os, Pt-Os, Lu-Hf, U-Pb(with discordant points),Pb-Pb and Ar-Ar.

关键词： Linear regression Isochron Geochronology Uncertainty propagation Monte Carlo Isoplot

Wafer-scale quasi-layered tungstate-doped polypyrrole film with high volumetric capacitance

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Nano Research 2023年第4期16卷 4895-4900页

作者： Huabo Liu Jiaxing Liang John Watt richard d.Tilley Rose Amal da-Wei Wang School of Chemical Engineering University of New South WalesSydneyNSW 2052Australia 2 Center for Integrated NanotechnologiesLos Alamos National LaboratoryLos AlamosNW 87545USA 3 School of ChemistryUniversity of New South WalesSydneyNSW 2052Australia

Layered materials are particularly attractive for supercapacitors because of their unique physical,electrical and chemical ***,we demonstrate a facile and scalable electrochemical deposition method for wafer-scale synthesis of quasilayered tungstate-doped polypyrrole films(named TALPy)with controllable thickness and *** as-prepared TALPy film exhibits a high gravimetric density and excellent volumetric capacitance,exceeding many high-performing carbon-and polymerbased film *** on combined results of ex-situ X-ray diffraction(XRd),Raman and X-ray photoelectron spectroscopy(XPS),it is determined that TALPy stores charge through an ion intercalation process accompanied by change in oxidation states of polypyrrole backbone,which is referred as intercalation *** these results suggest the great promise of electrochemical deposition as a scalable and controllable bottom-up approach for synthesizing quasi-layered conductive organic-inorganic hybrid films for electrochemical energy storage applications with high volumetric performance.

关键词： electrochemical deposition conductive polymer polypyrrole organic-inorganic hybrid supercapacitor intercalation pseudocapacitance

Molecular targets in the treatment of alcoholic hepatitis

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World Journal of Gastroenterology 2012年第39期18卷 5504-5513页

作者： Ashwin d dhanda richard WL Lee Peter L Collins C Anne McCune department of Liver Medicine University Hospitals Bristol NHS Foundation TrustBS2 8HW BristolUnited Kingdom department of Cellular and Molecular Medicine School of Clinical SciencesUniversity of BristolBS9 1TD BristolUnited Kingdom

Alcohol related costs to health and society are high. One of the most serious complications of alcohol misuse to the individual is the development of alcoholic hepatitis (AH), a clinical syndrome of jaundice and progressive inflammatory liver injury in patients with a history of recent heavy alcohol use. It has a poor outcome and few existing successful therapies. The use of glucocorticoids in patients with severe AH is still controversial and there remains a group of patients with glucocorticoid-resistant disease. However, as our understanding of the pathogenesis of the condition improves there are opportunities to develop new targeted therapies with specific actions to control liver inflammation without having a detrimental effect on the immune system as a whole. In this article we review the molecular mechanisms of AH concentrating on the activation of the innate and adaptive immune response. We consider existing treatments including glucocorticoids, anti-tumor necrosis factor therapy and pentoxifylline and their limitations. Using our knowledge of the disease pathogenesis we discuss possible novel therapeutic approaches. New targets include pro-inflammatory cytokines such as interleukin (IL)-17, chemokines and their receptors (for example IL-8, CXCL9 and CXCR3) and augmentation of anti-inflam- matory molecules such as IL-10 and IL-22. And there is also future potential to consider combination therapy to selectively modulate the immune response and gain control of disease.

关键词： Alcoholic hepatitis Tumour necrosis factor-m Pentoxifylline Interleukins Chemokine receptors

Explicit and Parameterized Episodes of Warm-Season Precipitation over the Continental United States

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Advances in Atmospheric Sciences 2006年第1期23卷 91-105页

作者： Mitchell W. MONCRIEFF John d. TUTTLE richard E. CARBONE National Center for Atmospheric Research BoulderColorado 80307-3000U. S. A.

This paper describes explicit and parameterized simulations of midsummer precipitation over the continental United States for two distinct episodes： moderate large-scale forcing and weak forcing. The objective is to demonstrate the capability of explicit convection at currently affordable grid-resolution and compare it with parameterized realizations. Under moderate forcing, 3-kin grid-resolution explicit simulations represent rainfall coherence remarkably well. The observed daily convective generation near the Continental divide and the subsequent organization and propagation are reproduced qualitatively. The propagation speed, zonal extent and duration of the rainfall streaks compare favorably with their observed counterparts, although the streak frequency is underestimated. The simulations at -10-km grid-resolution applying conventional convective parameterization schemes also replicate reasonably well the diurnal convective regeneration in moderate forcing. The performance of the 3-km grid-resolution model demonstrates the potential of -1-km-resolution explicit cloud-resolving models for the prediction of warm season precipitation for moderately forced environments. In weak forcing conditions, however, predictions of precipitation coherence and diurnal variability are much poorer. This suggests that an even finer resolution explicit model is required to adequately treat convective initiation and upscale organization typical of the warm season over the continental U.S.

关键词： warm-season precipitation explicit simulation convective parameterization