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Prognostic factors in patients hospitalized with acute heart failure syndrome

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Journal of Geriatric Cardiology 2006年第4期3卷 199-209页

作者： Liviu Klein john b.o’Connell Division of Cardiology Center for Heart Failure Northwestern University Feinberg School of MedicineChicagoIL 60611USA

Each year, there are over one million hospitalizations for acute heart failure syndrome (AHFS) in the United States alone,with a similar number in Western Europe. These patients have very high short-term (2-6 months) mortality and readmission rates, while the healthcare system incurs substantial costs. Until recently, the clinical characteristics, management patterns, and outcomes of these patients have been poorly understood and, in consequence, risk stratification for these patients has not been well defined. Several risk prediction models that can accurately identify high-risk patients have been developed in the last year using data from clinical trials, large registries or administrative databases. Use of multi-variable risk models at the time of hospital admission or discharge offers better risk stratification and should be encouraged, as it allows for appropriate allocation of existing resources and development of clinical trials testing new treatment strategies for patients admitted with AHFS. The emerging observation that the prognosis for the ensuing three to six months may be obtained at presentation for AHFS has major implications for development of future therapies.

关键词： heart failure hospitalization risk factors prognosis

Targeting Trkb–PSD-95 coupling to mitigate neurological disorders

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Neural Regeneration Research 2025年第3期20卷 715-724页

作者： Xin Yang Yu-Wen Alvin Huang john Marshall Department of Molecular b.ology Cell Biology and BiochemistryBrown UniversityProvidenceRIUSA Department of Neurology Warren Alpert Medical School of Brown UniversityProvidenceRIUSA Center for Translational Neuroscience Robert J.and Nancy D.Carney Institute for Brain Science and Brown Institute for Translational ScienceBrown UniversityProvidenceRIUSA

Tropomyosin receptor kinase b(Trkb)signaling plays a pivotal role in dendritic growth and dendritic spine formation to promote learning and *** activity-dependent release of brain-derived neurotrophic factor at synapses binds to pre-or postsynaptic Trkb resulting in the strengthening of synapses,reflected by long-term ***,the association of postsynaptic density protein-95 with Trkb enhances phospholipase Cγ-Ca^(2+)/calmodulin-dependent protein kinaseⅡand phosphatidylinositol 3-kinase-mechanistic target of rapamycin signaling required for long-term *** this review,we discuss Trkb-postsynaptic density protein-95 coupling as a promising strategy to magnify brain-derived neurotrophic factor signaling towards the development of novel therapeutics for specific neurological disorders.A reduction of Trkb signaling has been observed in neurodegenerative disorders,such as Alzheimer's disease and Huntington's disease,and enhancement of postsynaptic density protein-95 association with Trkb signaling could mitigate the observed deficiency of neuronal connectivity in schizophrenia and *** with brain-derived neurotrophic factor is problematic,due to poor pharmacokinetics,low brain penetration,and side effects resulting from activation of the p75 neurotrophin receptor or the truncated Trkb.T1 *** Trkb agonists and antibodies that activate Trkb are being intensively investigated,they cannot distinguish the multiple human Trkb splicing isoforms or cell type-specific *** Trkb–postsynaptic density protein-95 coupling provides an alternative approach to specifically b.ost Trkb signaling at localized synaptic sites versus global stimulation that risks many adverse side effects.

关键词： Angelman syndrome autism brain-derived neurotrophic factor depression neurodegenerative disorder neurodevelopmental disorder postsynaptic density protein-95 synaptic plasticity Trkb

Magnetohydrodynamic‑based Internal Cooling System for a Ceramic Cutting Tool:Concept Design,Numerical Study,and Experimental Evalidation

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Nanomanufacturing and Metrology 2023年第4期6卷 60-80页

作者： john o’Hara Fengzhou Fang Center of Micro/Nano Manufacturing Technology(MNMT-Dublin) University College DublinDublin 4Ireland State Key Laboratory of Precision Measuring Technology and Instruments Laboratory of Micro/Nano Manufacturing Technology(MNMT)Tianjin UniversityTianjin 300072China

The efective removal of the heat generated during mechanical cutting processes is crucial to enhancing tool life and produc-ing workpieces with superior surface *** internal cooling systems used in cutting inserts employ a liquid water-based solvent as the primary medium to transport the excess thermal energy generated during the cutting *** limitations of this approach are the low thermal conductivity of water and the need for a mechanical input to circulate the coolant around the inner chamber of the cutting *** this context,this paper proposes an alternative method in which liquid gallium is used as the coolant in combination with a magnetohydrodynamic(MHD)pump,which avoids the need for an external power *** computational fuid dynamics,we created a numerical model of an internal cooling system and then solved it under conditions in which a magnetic feld was applied to the liquid *** was followed by a simulation study performed to evaluate the efectiveness of liquid gallium over liquid *** results of experiments conducted under non-cooling and liquid gallium cooling conditions were analyzed and compared in terms of the tool wear *** results showed that after six machining cycles at a cutting speed Vc=250 m min−1,the corner wear Vbc rate was 75µm with the coolant of and 48µm with the MHD-based coolant on,representing a decrease of 36%in tool *** Vc=900 m min−1,the corner wear Vbc rate was 75µm with the coolant of and 246µm with the MHD-based coolant on,representing a decrease of 31%in tool *** external cooling using liquid water was added,the results showed at Vc=250 m min−1,the diference between the tool wear rate reduction with the internal liquid gallium coolant relative to the external coolant was 29%.When the cutting speed was increased to Vc=900 m min−1,the diference observed between the internal liquid gallium coolant relative to the external coolant was 16%.The study proves the feasibility of using liqu

关键词： Internal cooling Heat transfer Liquid metal Magnetic feld Cutting tool

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Introduction

Journal of Geriatric Cardiology 2006年第4期3卷 196-页

作者： john b.o’Connell MD Guest Editor Professor of Medicine Northwestern University Feinberg School of Medicine Director Center for Heart Failure Bluhm Cardiovascular Institute ChicagoUSA

　　Heart Failure (HF) is a major source of morbidity and mortality worldwide. In the United States, five million people carry this diagnosis. It accounts for in excess of one million hospitalizations and costs approximately $30 billion to *** elderly population is particularly affected since more than 80% of those hospitalized for HF are over age 65 *** the development of evidence-based therapy and guidelines in the management of chronic HF for use by physicians and other health care providers, the mortality remains high.……

关键词： HF

Sifting for small primes from an arithmetic progression

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Science China Mathematics 2023年第12期66卷 2715-2730页

作者： john b.Friedlander Henryk Iwaniec Department of Mathematics University of TorontoTorontoON M5S 2E4Canada Department of Mathematics Rutgers UniversityPiscatawayNJ 08903USA

In this work and its sister paper(Friedlander and Iwaniec(2023)),we give a new proof of the famous Linnik theorem bounding the least prime in an arithmetic *** sieve machinery in both papers,we are able to dispensh with the log-free zero density bounds and the repulsion property of exceptional zeros,two deep innovations begun by Linnik and relied on in earlier proofs.

关键词： sieve small primes Linnik theorem

Highly cross-linked polyethylene is the new‘gold standard’bearing material for total hip arthroplasty

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b.osurface and b.otribology 2021年第2期7卷 53-59页

作者： john b.Medley Department of Mechanical and Mechatronics Engineering University of WaterlooWaterlooOntarioCanada

Conventional polyethylene is not used much in total hip arthroplasty(THA);it has been supplanted by oxidation-resistant cross-linked polyethylene(≥50 kGy irradiation).However,studies persist that de-emphasize or ignore cross-linked polyethylene.A se-lective literature review is used briefly to present the early use of conventional poly-ethylene and its implication in wear particle-induced osteolysis leading to premature revision *** current situation is established based on Australian registry data and other studies that advocate the use of cross-linked polyethylene in preference to conventional *** some studies suggest caution in using cross-linked polyethylene,overall it is strongly *** the author’s opinion,cross-linked polyethylene is the new reference standard bearing material in THA.

关键词： cross Highly planted

Specific features of Eu^(3+) and Tb^(3+) magnetooptics in gadolinium-gallium garnet (Gd_3Ga_5o_(12))

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Journal of Rare Earths 2011年第8期29卷 776-782页

作者： Uygun V. Valiev john b. Gruber 付德君 Vasiliy o. Pelenovich Gary W. burdick Mariya E. Malysheva Faculty of Physics National University of Uzbekistan Department of Physics and Astronomy The University of Texas at San Antonio Department of Physics Wuhan University Department of Physics Andrews University

We reported magnetooptical properties of Eu3＋（4f（6）） and Tb3＋（4f（8）） in single crystals of Gd3Ga5o12 （GGG）, Y3Ga5o12 （YGG）, and Eu3＋（4f（6）） in Eu3Ga5o12 （EuGG） for both ions occupying sites of D2 symmetry in the garnet structure. Ab.orption, luminescence, and magnetic circular polarization of luminescence （MCPL） spectra of Tb3＋ in GGG and YGG and ab.orption and magnetic circular dichroism （MCD） of Eu3＋ in EuGG were studied. The data were obtained at 85 K and room temperature （RT）. Magnetic susceptibility of Eu3＋ in EuGG was also measured between 85 K and RT. The magnetooptical and magnetic susceptibility data were modeled using the wavefunctions of the crystal-field split energy （Stark） levels of Eu3＋ and Tb3＋ occupying D2 sites in the same garnets. The results reported gave a precise determination of these Stark level assignments and confirmed the symmetry labels （irreducible representations） of the closely-spaced Stark levels （quasi-doublets） found in the 5D1 （Eu3＋） and 5D4 （Tb3＋） multiplets. Ultraviolet （UV） excitation （300 nm） of the 6PJ and 6IJ states of Gd3＋ in the doped GGG crystals led to emission from 5D4 （Tb3＋） and 5D1 and 5D0 （Eu3＋） through radiationless energy transfer to the 4f（n–1）5d band of Tb3＋ and to UV quintet states of Eu3＋. The temperature-dependent emission line shapes and line shifts of the magnetooptical transitions excited by UV radiation suggested a novel way to explore energy transfer mechanisms in this rare-earth doped garnet system.

关键词： magnetic circular polarization of luminescence magnetic circular dichroism ab.orption quantum qutting energy transfer magnetic susceptibility rare earths

Magnetooptics of non-Kramers Eu^(3+) ions in garnets:analysis complemented by crystal-field splitting modeling calculations

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Journal of Rare Earths 2013年第9期31卷 837-842页

作者： Uygun V.Valiev john b.Gruber Anvar K.Mukhammadiev Vasiliy o.Pelenovich 付德君 Gary W.burdick Faculty of Physics National University of Uzbekistan Department of Physics and Astronomy The University of Texas at San Antonio School of Physics and Technology Wuhan University Department of Physics Andrews University

Spectra of ab.orption, luminescence, magnetic circular dichroism （MCD）, and magnetic circular polarization of lumines- cence （MCPL） in Gd3Ga5o12：Eu3＋ and Eu3Ga3o12 garnets were studied within the visible spectral range at 300 K. Analysis of the spectral and temperature dependences of the magnetooptical and optical spectra made it possible to identify the magneto-dipole （MD） and electro-dipole （ED） 4f→4f transitions occurring between Stark sublevels of the 7FJ （J=1, 2） and 5D0 multiplets in Eua＋-containing garnet structures. Quantum mechanical ＂mixing＂ had significant influence on quasi-degenerate states of the non-Kramers rare-earth Eu3＋ ion for Eu3Gasol2 in MCD due to forbidden MD transition 7F1→SD0 and for GdaGasoiE：EU3＋ in MCPL due to MD 4f→4f transition 5Do→7F1 and forced ED-transition 5Do→7F2. A parameterized Hamiltonian defined to operate within the entire 4f（6） ground electronic configuration of Eu3＋ ion was used to model the experimental Stark levels, including their irreducible rep- resentations and wavefunctions. The crystal-field parameters were determined through a Monte-Carlo method in which nine in- dependent crystal-field parameters, bkq, were given random starting values and optimized using standard least-squares fitting between calculated and experimental levels. The final fitting standard deviation between 57 calculated-to-experimental levels was 0.73 meV.

关键词： : magnetic circular dichroism magnetic circular polarization luminescence adsorption garnet non-Kramers ion rare earths

Study of hybrid nanofluid flow in a stationary cone-disk system with temperature-dependent fluid properties

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 677-694页

作者： A.S.john b.MAHANTHESH G.LoRENZINI Center for Mathematical Needs Department of MathematicsCHRIST(Deemed to be University)Karnataka 560029India School of Mathematical and Statistical Sciences The University of Texas Rio Grande ValleyTexas 78539U.S.A. Department of Engineering and Architecture University of ParmaParma 43124Italy

Cone-disk systems find frequent use such as conical diffusers,medical devices,various rheometric,and viscosimetry *** this study,we investigate the three-dimensional flow of a water-based Ag-Mg o hybrid nanofluid in a static cone-disk system while considering temperature-dependent fluid *** the variable fluid properties affect the dynamics and heat transfer features is studied by Reynolds's linearized model for variable viscosity and Chiam's model for variable thermal *** single-phase nanofluid model is utilized to describe convective heat transfer in hybrid nanofluids,incorporating the experimental *** model is developed as a coupled system of convective-diffusion equations,encompassing the conservation of momentum and the conservation of thermal energy,in conjunction with an incompressibility condition.A self-similar model is developed by the Lie-group scaling transformations,and the subsequent self-similar equations are then solved *** influence of variable fluid parameters on both swirling and non-swirling flow cases is ***,the Nusselt number for the disk surface is *** is found that an increase in the temperature-dependent viscosity parameter enhances heat transfer characteristics in the static cone-disk system,while the thermal conductivity parameter has the opposite effect.

关键词： hybrid nanofluid cone-disk system laminar flow variable fluid property Nusselt number