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MR Imaging of Knee Osteoarthritis and Correlation of Findings with Reported Patient Pain

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Journal of Huazhong University of Science and Technology(Medical Sciences) 2010年第2期30卷 248-254页

作者：艾飞余铖张炜 john N Morelli Kacher d 李小明 department of Radiology Tongji HospitalTongji Medical CollegeHuazhong University of Science and Technology department of Radiology Scott & White Clinic and HospitalTexas A&M University Health Science Center department of Radiology Brigham & Women's HospitalHarvard Medical School

Summary： To evaluate lesion detection of MRI in knee joint osteoarthritis in patients with symptoms of pain, the correlation between MRI findings and varying degrees of reported pain was assessed. Twenty-eight patients （31 knees） with osteoarthritis were recruited for this study. The degree of knee pain was assessed by VRS scores. The knees were evaluated by plain film radiograph utilizing Kellgren-Lawrence scores. Multiple MR sequences were performed on a 1.5T MR-system, including sagittal and coronal dual fast spin echo （TRITE 3660/11/120 ms, slice thickness 5 mm）, coronal spin echo T1-weighted （TR/TE 360/9 ms, slice thickness 5 mm）, sagittal fat saturated 3d-spoiled gradient-recalled echo （TR/TE 50/6 ms; slice thickness 1.5 mm; flip angle 40°）, and 3d steady-state free precession （TR/TE 6/2.2 ms; slice thickness 1.6 mm; flip angle 30°） pulse sequences for the purpose of detecting abnormities of cartilage, menisci, the anterior cruciate ligaments, bone marrow edema-like lesions, osteophytes, synovitis, and joint effusions. MR findings were compared with the degree of pain using Fisher exact test with P values less than 0.05 indicating a statistically significant difference. The results showed that, of the 31 knees evaluated, mild pain was reported in 11 and severe pain in the remainder. Kellgren-Lawrence scores of all 31 evaluated OA knees were as follows： grade 1 lesions （n=6）, grade 2 lesions （n=14）, grade 3 lesions （n=8）, and grade 4 lesions （n=3）. Articular cartilaginous defects were found in 37.1% of knees. Abnormalities of the menisci and anterior cruciate ligaments, bone marrow edema-like lesions, osteophytes, synovitis, and joint effusions were detected in 32.3%, 38.7%, 45.2%, 100%, 15.1% and 67.7% of knees, respectively. Of these variables, only the differences in prevalence of joint effusions were significantly different in the mild and severe pain groups （P=0.004）. It is concluded that MRI evaluates the entire joint structure of the osteoarthritic knee,

关键词： knee osteoarthritis magnetic resonance imaging pain

Effect of Explicit Water Molecules on the Color-Tuning Mechanism of the Firefly

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Chinese Journal of Chemistry 2011年第11期29卷 2301-2307页

作者：闵春刚邹陆一孙颖郭景富任爱民 Goddard, john d State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry Jilin University Changchun Jilin 130023 China School of Physics Northeast Normal University Changchun Jilin 130024 China department of Chemistry University of Guelph Guelph Ontario Canada NIG 2 W1

The contributions of explicit water molecules to color-tuning mechanism of firefly were studied. The explicit water molecules cause two different structures in the geometrical parameters of keto（-1） both in vacuo and aqueous solution. There are somewhat larger influences on absorption and emission spectra. When water molecules were added only on the side of benzothiazole ring, the spectra shift to the blue. In contrast, when waters were added only on the side of the thiazoline ring, the spectra shift to red. In a word, the color modulation of the emitted light depends on charge redistribution of molecule keto（-1）, mainly the charge change of the benzothiazole and thiazole tings at the two terminal in keto（-1）.

关键词： explicit water molecules firefly bioluminescence density functional theory absorption and emission spectra

Using doubly-Labeled Water to Measure Energy Expenditure in an Important Small Ectotherm drosophila melanogaster

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Journal of Genetics and Genomics 2014年第9期41卷 505-512页

作者： Matthew d.W.Piper Colin Selman john R.Speakman Linda Partridge Institute of Healthy Ageing Department of GeneticsEvolution and EnvironmentUniversity College LondonGower StreetLondonWCIE 6BTUK Institute of Biodiversity Animal Health and Comparative Medicine University of Glasgow Institute of Biological and Environmental Sciences University of Aberdeen State Key Laboratory of Molecular developmental Biology Institute of Genetics and Developmental BiologyChinese Academy of Sciences

Energy expenditure is a key variable in the study of ageing, and the fruit fly drosophila melanogaster is a model organism that has been used to make step changes in our understanding of the ageing process. Standard methods for measurement of energy expenditure involve placing individuals in metabolic chambers where their oxygen consumption and CO2 production can be quantified. These measurements require separating individuals from any social context, and may only poorly reflect the environment in which the animals normally live. The doubly-labeled water （dLW） method is an isotope-based technique for measuring energy expenditure which overcomes these problems. However, technical challenges mean that the smallest animals this method has been previously applied to weighed 50-200 mg. We overcame these technical challenges to measure energy demands in drosophila weighing 0.78 mg. Mass-specific energy expenditure varied between 43 and 65 mW·g^-1. These estimates are considerably higher than estimates using indirect calorimetry of drosophila in small metabolic chambers （around 18 mW·g^-1）. The methodology we have established extends downwards by three orders of magnitude the size of animals that can be measured using dLW. This approach may be of considerable value in future ageing research attempting to understand the genetic and genomic basis of ageing.

关键词： doubly-labeled water Respiration rate Effect of mating status and sex drosophila

Linewidth narrowing in self-injection-locked on-chip lasers

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Light(Science & Applications) 2023年第10期12卷 2074-2083页

作者： Emad Alkhazraji Weng W.Chow Frédéric Grillot john E.Bowers Yating Wan Integrated Photonics Lab King Abdullah University of Science and TechnologyThuwal 23955Saudi Arabia Sandia National Laboratories AlbuquerqueNM 87185-1086USA LTCI Télécom ParisInstitut Polytechnique de Paris91120 PalaiseauFrance department of Electronic and Computer Engineering University of California-Santa BarbaraSanta BarbaraCA 93106USA

Stable laser emission with narrow linewidth is of critical importance in many applications,including coherent communications,LIdAR,and remote *** this work,the physics underlying spectral narrowing of self-injection-locked on-chip lasers to Hz-level lasing linewidth is investigated using a composite-cavity *** integrated III–V/SiN lasers operating with quantum-dot and quantum-well active regions are analyzed with a focus on the effects of carrier quantum *** intrinsic differences are associated with gain saturation and carrier-induced refractive index,which are directly connected with 0-and 2-dimensional carrier densities of *** from parametric studies are presented for tradeoffs involved with tailoring the linewidth,output power,and injection current for different device *** both quantum-well and quantum-dot devices show similar linewidth-narrowing capabilities,the former emits at a higher optical power in the self-injection-locked state,while the latter is more ***,a multi-objective optimization analysis is provided to optimize the operation and design *** the quantum-well laser,minimizing the number of quantum-well layers is found to decrease the threshold current without significantly reducing the output *** the quantum-dot laser,increasing the quantum-dot layers or density in each layer increases the output power without significantly increasing the threshold *** findings serve to guide more detailed parametric studies to produce timely results for engineering design.

关键词： narrowing injection quantum

Summer egg diapause in a matchstick grasshopper synchronizes the life cycle and buffers thermal extremes

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Integrative Zoology 2018年第4期13卷 437-449页

作者： Michael R.KEARNEY john dEUTSCHER Jacinta d.KONG Ary A.HOFFMANN School of BioSciences The University of MelbourneParkvilleAustralia

The phenological response is among the most important traits affecting a species’sensitivity to *** insects,strongly seasonal environments often select for a univoltine life cycle such that one seasonal extreme is avoided as an inactive *** understanding the underlying mechanisms for univoltinism,and the consequences of its failure,we can better predict insect responses to climate *** we combine empirical data and simulation studies to investigate the consequences of an unusual diapause mechanism in a parthenogenetic matchstick grasshopper,Warramaba virgo,from arid southern *** field body temperature measurements indicate that this species is a thermoconformer and our laboratory studies of the thermal response of feeding rate imply strong constraints on winter ***,the species exhibits no obligate winter diapause,and eggs can develop in 1 month under constant temperatures approximating the mean soil temperature at the time of oviposition(summer).We show that diurnal temperature cycles exceeding a peak of 36℃ inhibit egg development in summer,and that this is sufficient to prevent autumnal hatching of *** is also strongly retarded below 24℃.Microclimate-driven simulation studies of egg development show that these thermal responses provide robust maintenance of a univoltine life cycle,thereby resulting in survival of heat stress as an egg(due to limited developmental state)and avoidance of cold stress as a nymph and adult(due to overwintering in the soil as an egg).

关键词： egg diapause life cycle matchstick grasshopper phenology thermal extremes thermoregulation

Three-dimensional impact kinetics with foot-strike manipulations during running

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Journal of Sport and Health Science 2017年第4期6卷 489-497页

作者： Andrew d. Nordin Janet S. dufek john A. Mercer department of Kinesiology and Nutrition Sciences University of Nevada Las Vegas NV 89154 USA

Background: Lack of an observable vertical impact peak in fore/mid-foot running has been suggested as a means of reducing lower extremity impact forces, although it is unclear if impact characteristics exist in other axes. The purpose of the investigation was to compare three-dimensional(3 d) impact kinetics among foot-strike conditions in over-ground running using instantaneous loading rate–time ***: Impact characteristics were assessed by identifying peak loading rates in each direction(medial–lateral(ML), anterior–posterior(AP),vertical, and 3 d resultant) following foot-strike instructions(fore-foot, mid-foot, subtle heel, and obvious heel strike). Kinematic and kinetic data were analyzed among 9 male participants in each foot-strike ***: Loading rate peaks were observed in each direction and foot-strike condition, differing in magnitude by direction(3 d resultant and vertical > AP > ML, p ≤ 0.031) and foot-strike: ML(fore-foot and mid-foot strike > obvious heel strike, p ≤ 0.032), AP(fore-foot and mid-foot strikes > subtle-heel and obvious heel strikes, p ≤ 0.023). In each direction, the first loading rate peak occurred later during heel strike running relative to fore-foot(p ≤ 0.019), with vertical and 3 d resultant impact durations exceeding shear(ML and AP, p ≤ 0.007) in each ***: Loading rate–time assessment identified contrasting impact characteristics in each direction and the 3 d resultant following foot-strike manipulations, with potential implications for lower extremity structures in running.

关键词： Fore-foot Heel strike Loading rate Mid-foot Overground Resultant

Leading Approaches to Vascularize Kidney Constructs in Tissue Engineering

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Engineering 2022年第12期19卷 117-127页

作者： diana S.Lim john d.Jackson Anthony Atala James J.Yoo Wake Forest Institute for Regenerative Medicine Wake Forest University School of MedicineMedical Center BoulevardNC 27157USA

There is an unprecedented need for new treatments for renal failure,as the incidence of this disease is increasing disproportionately to advancements in *** treatments are limited by the availability of viable organs,for which there is a worldwide *** treatment modalities also require a substantial amount of infrastructure,significantly limiting the access to care in most *** tissue engineering approaches promise to develop alternative solutions that address many of the inadequacies in current *** many advancements have been made—primarily in the past decade—in biofabrication and whole-organ tissue engineering,many challenges *** major hindrance to the progress of current tissue engineering approaches is establishing successful vascularization of developed engineered tissue *** review focuses on the recent advancements that address the vascular challenge,including the biofabrication of vasculature,whole-organ engineering through decellularization and recellularization approaches,microscale organogenesis,and vascularization using organoids in the context of kidney tissue *** also highlight the specific challenges that remain in developing successful strategies capable of clinical translation.

关键词： Kidney Vascularization Tissue engineering Biofabrication Organoids

detection and identification of S1 and S2 heart sounds using wavelet decomposition method

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International Journal of Biomathematics 2015年第6期8卷 141-155页

作者： Ali Tavakoli Golpaygani Nahid Abolpour Kamran Hassani d. john doyle Biomedical Engineering departmentFaculty of Electrical Mechanical and Construction Engineering Standard Research Institute Karaj Iran department of Physics and Biomedical EngineeringShiraz University of Medical Sciences Shiraz Iran department of Biomechanics Science and Research Branch Islamic Azad University Tehran Iran department of General AnesthesiologyAnesthesiology Institute Cleveland Clinic Abu Dhabi Abu Dhabi UAE

Phonocardiogram （PCG）, the digital recording of heart sounds is becoming increasingly popular as a primary detection system for diagnosing heart disorders and it is relatively inexpensive. Electrocardiogram （ECG） is used during the PCG in order to identify the systolic and diastolic parts manually. In this study a heart sound segmentation algorithm has been developed which separates the heart sound signal into these parts automa- tically. This study was carried out on 100 patients with normal and abnormal heart sounds. The algorithm uses discrete wavelet decomposition and reconstruction to pro- duce PCG intensity envelopes and separates that into four parts： the first heart sound, the systolic period, the second heart sound and the diastolic period. The performance of the algorithm has been evaluated using 14,000 cardiac periods from 100 digital PCG recordings, including normal and abnormal heart sounds. In tests, the algorithm was over93% correct in detecting the first and second heart sounds. The presented automatic seg- mentation Mgorithm using w^velet decomposition and reconstruction to select suitable frequency band for envelope calculations has been found to be effective to segment PCG signals into four parts without using an ECG.

关键词： Phonocardiography auscultation murmurs wavelet decomposition waveletreconstruction segmentation.

Etiology,diagnosis, management and outcomes of epiphora referrals to an oculoplastic practice

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International Journal of Ophthalmology(English edition) 2016年第12期9卷 1751-1755页

作者： Guang-Lin Shen john d.Ng Xiao-Ping Ma department of Ophthalmology Zhongshan Hospital of Fudan University Casey Eye Institute Oregon Health and Science University

AIM： To investigate the etiology, diagnosis, management and outcome of epiphora referrals to an oculoplastic ***： Retrospective chart review of patients referred for epiphora to an oculoplastic clinic between 2005 and 2009. Patient demographics, past history, ophthalmic examination, treatment and outcome were ***： There were 237 subjects with a primary complaint of epiphora. They included 130 （55%） females and 107 （45%） males with an average age of 55.9±25.9y. The most common cause of epiphora was lacrimal obstruction （46%）; followed by multifactorial epiphora （22%）, reflex tearing （22%） and eyelid malposition （11%）. differences in prevalence of etiology were noted in terms of age and gender distribution. Of the 182 （77%） patients who returned for follow up, 41 （23%） reported a complete resolution and 102 （56%） reported a significant improvement in their ***： Epiphora is a common condition with many causes. A thorough history and examination are required to provide the appropriate treatment tailored to the underlying cause.

关键词： epiphora etiology lacrimal disease dry eye