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detecting neurodegenerative pathology in multiple sclerosis before irreversible brain tissue loss sets in

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Translational Neurodegeneration 2019年第1期8卷 466-482页

作者： Jeroen Van Schependom Kaat Guldolf Marie Béatrice d’hooghe guy Nagels Miguel d’haeseleer Neurology department Universitair Ziekenhuis BrusselCenter for NeurosciencesVrije Universiteit BrusselLaarbeeklaan 1011090 BrusselBelgium Radiology department Universitair Ziekenhuis Brussel BrusselsBelgium Nationaal Multiple Sclerose Centrum MelsbroekBelgium

Background:Multiple sclerosis(MS)is a complex chronic inflammatory and degenerative disorder of the central nervous *** brain volume loss,or also termed atrophy,is currently emerging as a popular imaging marker of neurodegeneration in affected patients,but,unfortunately,can only be reliably interpreted at the time when irreversible tissue damage likely has already *** of treatment decisions based on brain atrophy may therefore be viewed as *** body:This Narrative Review focuses on alternative techniques with the potential of detecting neurodegenerative events in the brain of subjects with MS prior to the atrophic ***,metabolic and molecular imaging provide the opportunity to identify early subcellular changes associated with energy dysfunction,which is an assumed core mechanism of axonal degeneration in ***,cerebral hypoperfusion has been observed throughout the entire clinical spectrum of the disorder but it remains an open question whether this serves as an alternative marker of reduced metabolic activity,or exists as an independent contributing process,mediated by endothelin-1 ***,both metabolic and perfusion alterations may lead to repercussions at the level of network performance and structural connectivity,respectively assessable by functional and diffusion tensor *** and finally,elevated body fluid levels of neurofilaments are gaining interest as a biochemical mirror of axonal damage in a wide range of neurological conditions,with early rises in patients with MS appearing to be predictive of future brain ***:Recent findings from the fields of advanced neuroradiology and neurochemistry provide the promising prospect of demonstrating degenerative brain pathology in patients with MS before atrophy has *** the overall level of evidence on the presented topic is still preliminary,this Review may pave the way for further longitudinal and multimodal studi

关键词： Brain atrophy magnetic resonance imaging multiple sclerosis neurodegeneration neurofilaments

Retinal sub-layer thicknesses, presence of lacunes, and their interaction with cognitive performance in recent single subcortical infarction

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中华医学杂志(英文版) 2024年第16期137卷 2024 Jul 19页

作者： Cui Jingyu Kwapong William robert Yan Yuying Cao Le Ye Chen Wang Hang Jiang Shuai Wu Bo department of Neurology West China Hospital Sichuan University Chengdu Sichuan China

An assessment of coal pillar system stability criteria based on a mechanistic evaluation of the interaction between coal pillars and the overburden

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International Journal of Mining Science and Technology 2017年第1期27卷 9-15页

作者： Reed.guy Mctyer Kent Frith Russell Mine Advice Pry Ltd NewcastleNSW 2322Australia

Coal pillar design has historically assigned a factor of safety(Fo S) or stability factor(SF) according to their estimated strength and the assumed overburden load acting on them. Acceptable Fo S values have been assigned based on past mining experience or a statistical link between Fo S and probability of failure(Po F). Pillar width-to-height(w/h) ratio has long been established as having a material influence on both pillar strength and its potential failure mode. However, there has been significant disagreement on using both factor of safety(Fo S) and w/h as part of pillar system stability criterion, as compared to using Fo S in isolation. This paper will argue that there are valid technical reasons to bring w/h ratio into system stability criteria(other than its influence on pillar strength), as it is related to the post-failure stiffness of the pillar, as measured in situ, and its interaction with overburden stiffness. When overburden stiffness is also brought into pillar system stability considerations, two issues emerge. The first is the width-todepth(W/d) ratio of the panel and whether it is sub-critical or super-critical from a surface subsidence perspective. The second relates to a re-evaluation of pillar Fo S based on whether the pillar is in an elastic or non-elastic(i.e., post-yield) state in its as-designed condition, as this is relevant to maintaining overburden stiffness at the highest possible level. The significance of the model is the potential to maximise both reserve recovery and mining efficiencies without any discernible increase in geotechnical risk, particularly in thick seams and higher depth of cover mining situations. At a time when mining economics are, at best, marginal, removing potentially unnecessary design conservatism is of interest to all mine operators and is an important topic for discussion amongst the geotechnical community.

关键词： Coa] pillars Stability Overburden Post-failure behaviour Stability criteria

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INVARIANCE ANd STABILITY OF THE PROFILE EQUATIONS OF GEOMETRIC OPTICS

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Acta Mathematica Scientia 2011年第6期31卷 2141-2158页

作者： guy Mtivier Jeffrey Rauch Institut de Mathmatiques de Bordeaux Universit de Bordeaux department of Mathematics University of Michigan

The profile equations of geometric optics are described in a form invariant under the natural transformations of first order systems of partial differential equations. This allows us to prove that various strategies for computing profile equations are equivalent. We prove that if L generates an evolution on L2 the same is true of the profile equations. We prove that the characteristic polynomial of the profile equations is the localization of the characteristic polynomial of the background operator at （y, dφ（y）） where φ is the background phase. We prove that the propagation cones of the profile equations are subsets of the propagation cones of the background operator.

关键词： geometric optics profile equation localisation vector bundles propagation cones

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Impact of a physician-supervised exercise-nutrition program with testosterone substitution in partial androgen-deficient middle-aged obese men

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Journal of Geriatric Cardiology 2011年第4期8卷 201-206页

作者： Ernst R Schwarz robert d Willix Jr Cenegenics Education and Research Foundation Las Vegas and Heart Institute of Southern CaliforniaBeverly Hills348 S Oakhurst DrBeverly HillsCA 90212USA

Background Partial androgen deficiency syndrome in the aging male is associated with signs of aging such as a development of abdominal obesity,sexual dysfunction,increase body fat,weight gain and the development of cardiac *** We assessed the outcome of a commercially available physician supervised nutrition and exercise program with concomitant testosterone replacement therapy in middle age obese men with partial androgen deficiency in order to reduce cardiac risks *** Fifty-six self referred men without diabetes mellitus,hypertension,or cardiovascular disease(ages 52.3±7.8 years)were randomly selected from a large *** weight,body fat composition,fasting glucose,hemoglobin A1c and fasting lipid levels,as well as free and total testosterone levels were *** patients were assessed and followed 6–18 months after initiation of the *** program consisted of a low glycemic load balanced nutrition diet,a recommended structured daily exercise program of 30–60 minutes,as well as once to twice weekly intramuscular testosterone injections(113.0±27.8 mg).Results At follow up,weight was reduced from 233.9±30.0 pounds(lbs)to 221.3±25.1 lbs(Pduced from 33.2±3.3 kg/m2 to 31.3±2.8 kg/m^(2)(Pdy fat was 27.1%±5.2%vs.34.3%±5.7%at baseline(Pduced from 95.3±14.4 mg/dL to 87.5±12.6 mg/dL(Pduced from 195.4±33.0 mg/dL to 172.7±35.0 mg/dL(Pdverse events were *** Testosterone replacement therapy in middle aged obese men with partial androgen deficiency appeared safe and might have promoted the effects of a weight reduction diet and daily exercise program as long as an adequate physician supervision and follow up was *** combination therapy significantly reduced coronary risk factors such as glucose intolerance and hyperlipidemia.

关键词： aging heart disease androgen deficiency testosterone

Continuous frequency and phase spectrograms: a study of their 2d and 3d capabilities and application to musical signal analysis

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第2期9卷 199-206页

作者： Laurent NAVARRO guy COURBEBAISSE Jean-Charles PINOLI Ecole Nationale Supérieure des Mines de Saint-Etienne Centre Ingénierie et Santé (CIS) and LPMG UMR 5148 CNRS 158 cours Fauriel 42023 Saint-Etienne cedex 2 France Medical Imaging Research Center (CREATIS-LRMN) UMR 5220 CNRS U630 INSERM Université Lyon 1 INSA Lyon Bat. Blaise Pascal 7 Av. Jean Capelle 69621 Villeurbanne France

A new lighting and enlargement on phase spectrogram （PS） and frequency spectrogram （FS） is presented in this paper. These representations result from the coupling of power spectrogram and short time Fourier transform （STFT）. The main contribution is the construction of the 3d phase spectrogram （3dPS） and the 3d frequency spectrogram （3dFS）. These new tools allow such specific test signals as small slope linear chirp, phase jump case of musical signal analysis is reported. The main objective is to and small frequency jump to be analyzed. An application detect small frequency and phase variations in order to characterize each type of sound attack without losing the amplitude information given by power spectrogram

关键词： Frequency spectrogram (FS) Phase spectrogram (PS) Time-frequency representations Musical signals

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Three-dimensional analysis of age and sex differences in femoral head asphericity in asymptomatic hips in the United States

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World Journal of Orthopedics 2024年第8期15卷 754-763页

作者： Mahad M Hassan Aliya G Feroe Brenton W douglass Andrew E Jimenez Benjamin Kuhns Charles F Mitchell robert L Parisien daniel A Maranho Eduardo N Novais Young-Jo Kim Ata M Kiapour department of Orthopedic Surgery University of MinnesotaMinneapolisMN 55454United States department of Orthopedic Surgery TRIA Orthopaedic CenterBloomingtonMN 55122United States department of Orthopedic Surgery Boston Children’s HospitalBostonMA 02115United States department of Orthopedic Surgery Mayo ClinicRochesterMN 55901United States department of Orthopaedics and Rehabilitation Yale School of MedicineNew HavenCT 06510United States department of Orthopedic Surgery American Hip Institute Research FoundationDes PlainesIL 60018United States department of Orthopedic Surgery Mount SinaiNew YorkNY 10029United States department of Biomechanics Medicineand Rehabilitation of the Locomotor SystemRibeirao Preto Medical SchoolUniversity of São PauloRibeirao Preto 14048-900São PauloBrazil

BACKGROUNd The sphericity of the femoral head is a metric used to evaluate hip pathologies and is associated with the development of osteoarthritis and femoral-acetabular *** To analyze the three-dimensional asphericity of the femoral head of asymptomatic pediatric *** hypothesized that femoral head asphericity will vary significantly between male and female pediatric hips and increase with age in both *** Computed tomography scans were obtained on 158 children and adolescents from a single institution in the United States(8-18 years;50%male)without hip *** femoral measurements including the femoral head diameter,femoral head volume,residual volume,asphericity index,and local diameter difference were used to evaluate femoral head *** In both sexes,the residual volume increased by age(Pdespite significantly smaller femoral head size in older ages(>13 years)in females,there were no sex-differences in residual volume and aspherity *** were no age-related changes in mean diameter difference in both sexes(P=0.07)with no significant sex-differences across different age groups(P=0.06).In contrast,there were significant increases in local aspherity(maximum diameter difference)across whole surface of the femoral head and all quadrants except the inferior regions in males(P=0.03).There were no sex-differences in maximum diameter difference at any regions and age group(P>0.05).Increased alpha angle was only correlated to increased mean diameter difference across overall surface of the femoral head(P=0.024).CONCLUSION There is a substantial localized asphericity in asymptomatic hips which increases with age *** 2d measured alpha angle can capture overall asphericity of the femoral head,it may not be sensitive enough to represent regional asphericity patterns.

关键词： Hip Femoral head Sphericity Skeletal growth Sex differences

Rapid micro-immunohistochemistry

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Microsystems & Nanoengineering 2020年第1期6卷 285-294页

作者： robert d.Lovchik david Taylor Govind Kaigala IBM Research Europe Saeumerstrasse 48803 RueschlikonSwitzerland Present address:Eidgenossische Technische Hochschule Zurich Department of Mechanical and Process EngineeringSonneggstrasse 38092 ZurichSwitzerland

We present a new and versatile implementation of rapid and localized immunohistochemical staining of tissue ***(IHC)comprises a sequence of specific biochemical reactions and allows the detection of specific proteins in tissue *** the rapid implementation of IHC,we fabricated horizontally oriented microfluidic probes(MFPs)with functionally designed apertures to enable square and circular footprints,which we employ to locally expose a tissue to time-optimized sequences of different *** show that the two main incubation steps of IHC protocols can be performed on MdAMB468-1510A cell block sections in less than 30 min,compared to incubation times of an hour or more in standard *** analysis on the timescale of tens of minutes could potentially be applied during surgery,enabling clinicians to react in more dynamically and ***,this rapid IHC implementation along with conservative tissue usage has strong potential for the implementation of multiplexed assays,allowing the exploration of optimal assay conditions with a small amount of tissue to ensure high-quality staining results for the remainder of the sample.

关键词： versatile steps sections

“Bull’s eye”appearance of hepatocellular adenomas in patients with glycogen storage disease type I-atypical magnetic resonance imaging findings:Two case reports

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World Journal of Clinical Cases 2021年第4期9卷 871-877页

作者： Federica Vernuccio Stephanie Austin Mathias Meyer Cynthia d.guy Priya S Kishnani daniele Marin department of Biomedicine Neuroscience and Advanced DiagnosticsUniversity of PalermoPalermo 90100Italy departments of Pediatrics Duke University Medical CenterDurhamNC 27710United States department of Radiology Duke University Medical HospitalDurhamNC 27708United States department of Pathology Duke UniversityDurhamNC 27710United States division of Medical Genetics Department of PediatricsDuke University Medical CenterDurhamNC 27710United States department of Radiology Duke University Medical CenterDurhamNC 27710United States

BACKGROUNd Hepatocellular adenomas are rare tumors that can occur in patients with glycogen storage disease type *** SUMMARY We herein report two cases of histologically proven hepatocellular adenomas in patients with glycogen storage disease type *** resonance imaging(MRI)was performed after bolus injection of gadoxetate disodium,a liver-specific gadolinium-based MRI contrast *** the present cases,some of the hepatocellular adenomas showed unexpectedly a“bull’s eye”appearance on T2-weighted and post-contrast images,which was not previously described as imaging findings of hepatocellular adenomas in glycogen storage disease.A bull’s eye appearance on T2-weighted images can be encountered in both benign(i.e.,abscess)or malignant(i.e.,epithelioid hemangioendothelioma,cholangiocarcinoma,and metastases)hepatic *** We present two cases of hepatocellular adenomas in patients with glycogen storage disease type 1,in which gadoxetate disodium-MRI showed atypical imaging findings for hepatocellular *** present there is no systematic study evaluating MRI findings of hepatocellular adenomas in patients with glycogen storage disease,further studies are needed to specifically investigate this issue.

关键词： Glycogen storage disease Hepatocellular adenoma Bull’s eye Magnetic resonance imaging Case report Gadoxetate disodium