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An integrative insight into the synsacral canal of fossil and extant Antarctic penguins

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Integrative Zoology 2023年第2期18卷 237-253页

作者： Piotr JADWISZCZAK Anders SVENSSON-mARCIAL thomas mÖRS Faculty of Biology University of BialystokBialystokPoland Department of Clinical Science Intervention and Technology at Karolinska InstituteStockholmSweden Department of Palaeobiology Swedish Museum of Natural HistoryStockholmSweden

The lumbosacral-canal system in birds most likely operates as a sense organ involved in the control of balanced walking and perching,but our knowledge of it is superﬁ*** constitute interesting objects for the study of this system due to their upright walking,but only the Humboldt penguin,Spheniscus humboldti,and some incomplete fossil penguin synsacra have been studied in this ***,we give an integrative comparative in-sight into the synsacral canal of extant Emperor penguin,Aptenodytes forsteri,Adelie penguin,Pygoscelis adeliae,and Eocene giant Anthropornis and/or Palaeeudyptes Antarctic penguins,using computed tomography imaging and associated data-extraction methodologies,complemented by analytical approaches ranging from geometric morphometrics to modularity,curvature,and wavelet *** document that the variability in the number of synsacro-lumbar vertebrae is evolutionarily conserved,and all studied synsacra possess osteological correlates of the lumbosacral-canal *** also found that Eocene and extant Antarctic penguins were separable on the basis of the main direction of the shape-related(size-independent)variability within said system,and *** was unique in the entire studied set in terms of the relative cranial shift of this compound ***,we suggest that the evolutionary processes,shaping both the terrestrial posture and gait,were responsible,in extant penguins,for the increased simplicity and stability of the synsacral canal cross-sectional periodic patterns,as well as pave the way for the lumbosacral-canal system modularity characterized by reduced atomization/complexity.

关键词： Antarctica Cenozoic lumbosacral canals Sphenisciformes synsacrum

Kinematic and Dynamic Analysis of a 3-■US Spatial Parallel manipulator

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Chinese Journal of mechanical Engineering 2020年第1期33卷 114-130页

作者： mervin Joe thomas m.L.Joy A.P.Sudheer mechatronics/Robotics Lab Department of Mechanical EngineeringNational Institute of Technology CalicutKozhikodeIndia

Parallel Kinematic machines(PKms)are being widely used for precise applications to achieve complex motions and variable poses for the end effector *** are found in medical,assembly and manufacturing industries where accuracy is *** is often desired to have a compact and simple architecture for the robotic *** this paper,the kinematic and dynamic analysis of a novel 3-PRUS(P:prismatic joint,R:revolute joint,U:universal joint,S:spherical joint)parallel manipulator with a mobile platform having 6 Degree of Freedom(Do F)is *** kinematic equations for the proposed spatial parallel mechanism are formulated using the modified Denavit-Hartenberg(DH)technique considering both active and passive *** kinematic equations are used to derive the Jacobian matrix of the mechanism to identify the singular points within the workspace.A Jacobian based sti ness analysis is done to understand the variations in sti ness for different poses of the mobile platform and further,it is used to decide trajectories for the end effector within the singularity free *** analytical model of the robot dynamics is presented using the Euler-Lagrangian approach with Lagrangian multipliers to include the system *** gravity and inertial forces of all links are considered in the mathematical *** analytical results of the dynamic model are compared with ADAmS simulation results for a pre-defined trajectory of the end effector.

关键词： Parallel manipulator Kinematic modelling Workspace analysis Euler-Lagrangian modelling Singularity analysis Stiffness analysis

Synthesis and electronic properties of expanded 5-(hetero)arylthien-2-yl substituted 3-ethynyl quinoxalines with AIE characteristics

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Science China Chemistry 2018年第8期61卷 909-924页

作者： Franziska K.merkt thomas J.J.müller Institute of Organic Chemistry and macromolecular Chemistry Heinrich Heine University Düsseldorf

Expanded 5-(hetero)aryl-thien-2-yl substituted 3-ethynyl quinoxaline dyes with variable substitution pattern on the peripheral thiophene ring were synthesized in moderate to very good yields by Suzuki and Buchwald-Hartwig coupling of the corresponding brominated 3-ethynyl quinoxalines. Dumbbell-shaped bis(thienyl 3-ethynyl quinoxalines) are also accessible by the Suzuki protocol. The photophysical properties were investigated by UV and fluorescence spectroscopy. most of the obtained compounds display fluorescence in solution and some of them also in the solid state. Additionally, tuning of the emission color of the quinoxaline based chromophores can be conveniently accomplished by the remote substituent group. The determined absorption and emission maximum as well as the Stokes shifts strongly correlate with Hammett σp+parameters. Besides,photophysical properties of selected derivatives in the solid state, biphasic solutions, and PmmA films, along with their relationships, are comparatively investigated. moreover, two 5-(hetero)aryl-thien-2-yl substituted 3-ethynyl quinoxaline dyes are aggregation induced emission(AIE) chromophores indicated by restriction of molecular motions. A covalently restricted 3-ethynyl quinoxaline supports that the inhibition of molecular rotation is responsible for the significant enhancement of fluorescence in acetonitrile/water mixtures.

关键词： absorption aggregation induced emission cross-coupling fluorescence heterocycles palladium

Ion Channels at the Nucleus： Electrophysiology meets the Genome

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molecular Plant 2010年第4期3卷 642-652页

作者： Antonius J.m. matzkea thomas m. Weiger marjori matzke Gregor mendel Institute of molecular Plant Biology Austrian Academy of Sciences Dr. Bohr-Gasse 3 A-1030 Vienna Austria Department of Cell Biology University of Salzburg A-5020 Salzburg Austria

The nuclear envelope is increasingly viewed from an electrophysiological perspective by researchers interested in signal transduction pathways that influence gene transcription and other processes in the nucleus. Here, we describe evidence for ion channels and transporters in the nuclear membranes and for possible ion gating by the nuclear pores. We argue that a systems-level understanding of cellular regulation is likely to require the assimilation of nuclear electrophysiology into molecular and biochemical signaling pathways.

关键词： Ion channel nuclear Ca^+2 signaling nuclear electrophysiology nuclear membrane nuclear pore.

How will the latest modifications to the CG189 NICE guidelines for obesity management likely impact clinical care?

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Hepatobiliary Surgery and Nutrition 2023年第3期12卷 413-416页

作者： thomas m.Barber Warwickshire Institute for the Study of Diabetes Endocrinology and MetabolismUniversity Hospitals Coventry and WarwickshireClifford Bridge RoadCoventryUK Division of Biomedical Sciences Clinical Sciences Research LaboratoriesWarwick Medical SchoolUniversity of WarwickCoventryUK

Based on the 2019 Health Survey for England,nearly two thirds of the adult population and one third of children(aged 2-15 years)are either overweight or obese(1).In England,obesity affects 28%of adults,20%of boys and 13%of girls(1).Obesity is a chronic,often life-long disease that associates with>50 weight-related conditions,most notably type 2 diabetes mellitus(T2D),and other dysmetabolic conditions that contribute towards the metabolic syndrome and many other conditions that impact on nearly every aspect of physiology and mental functioning(2).Obesity has a huge economic burden,with government estimates indicating the current costs of obesity in the UK at£6.1 billion to the National Health Service(NHS),and£27 billion to wider society(1).Despite this,obesity remains fundamentally misunderstood and *** is reflected by woeful under-funding of management strategies for obesity(despite many of these being highly efficacious),guidelines that place time-limitations on potentially effective therapies(with possible negative outcomes that stem from subsequent weight re-gain),and a prevailing fog of obesity-related stigma that seems to pervade its way throughout society like a contagion.

关键词： Obesity compassion awareness adaptability

models for lifetime estimation： an overview with focus on applications to wind turbines

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Advances in manufacturing 2014年第1期2卷 79-87页

作者： thomas m. Weite Ke-Sheng Wang SINTEF Energy Research 7465 Trondheim Norway Department of Production and Quality Engineering NorwegianUniversity of Science and Technology Trondheim Norway

This paper provides an overview of models and methods for estimation of lifetime of technical components. Although the focus in this paper is on wind turbine applications, the major content of the paper is of general nature. Thus, most of the paper content is also valid for lifetime models applied to other technical systems. The models presented and discussed in this paper are classified in different types of model classes. The main classification used in this paper divides the models in the following classes： physical models, stochastic models, data-driven models and artificial intelligence, and combined models. The paper provides an overview of different models for the different classes. Furthermore, advantages and disadvantages of the models are discussed, and the estimation of model parameters is briefly described. Finally, a number of literature examples are given in this paper, providing an overview of applications of different models on wind turbines.

关键词： Lifetime estimation model classification Wind turbine

Formulation of self-nanoemulsifying drug delivery systems containing monoacyl phosphatidylcholine and Kolliphor^(■) RH40 using experimental design

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Asian Journal of Pharmaceutical Sciences 2018年第6期13卷 536-545页

作者： Thuy Tran thomas Rades Anette müllertz Department of Pharmacy Faculty of Health and Medical Sciences University of Copenhagen Bioneer: FARmA Faculty of Health and Medical Sciences University of Copenhagen

The development of self-nanoemulsifying drug delivery systems(SNEDDS) to enhance the oral bioavailability of lipophilic drugs is usually based on traditional one-factor-at-a-time approaches. These approaches may be inadequate to analyse the effect of each excipient and their potential interactions on the emulsion droplet size formed when dispersing the SNEDDS in an aqueous environment. The current study investigates the emulsion droplet sizes formed from SNEDDS containing different levels of the natural surfactant monoacyl phosphatidylcholine to reduce the concentration of the synthetic surfactant polyoxyl 40 hydrogenated castor oil(Kolliphor ~? RH40). monoacyl phosphatidylcholine was used in the form of Lipoid S LPC 80(LPC, containing approximately 80% monoacyl phosphatidylcholine, 13% phosphatidylcholine and 4% concomitant components). The investigated SNEDDS comprised of long-chain or medium-chain glycerides(40% to 75%), Kolliphor ~? RH40(5% to 55%), LPC(0 to 40%) and ethanol(0 to 10%). D-optimal design, multiple linear regression, and partial least square regression were used to screen different SNEDDS within the investigated excipient ranges and to analyse the effect of each excipient on the resulting droplet size of the dispersed SNEDDS measured by dynamic light scattering. All investigated formulations formed nano-emulsions with droplet sizes from about 20 to 200 nm. The use of mediumchain glycerides was more likely to result in smaller and more monodisperse droplet sizes compared to the use of long-chain glycerides. Kolliphor~? RH40 exhibited the most significant effect on reducing the emulsion droplet sizes. Increasing LPC concentration increased the emulsion droplet sizes, possibly because of the reduction of Kolliphor~? RH40 concentration. A higher concentration of ethanol resulted in an insignificant reduction of the emulsion droplet size. The study provides different ternary diagrams of SNEDDS containing LPC and Kolliphor ~? RH40 as a reference for form

关键词： monoacyl phosphatidylcholine Self-nanoemulsifying drug delivery systems D-optimal design Polyoxyl 40 hydrogenated castor oil Kolliphor^(■)(RH40) Droplet size Cryogenic transmission electron microscopy

Predation changes the shape of thermal performance curves for population growth rate

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Current Zoology 2016年第5期62卷 501-505页

作者： thomas m. LUHRING John P. DELONG School of Biological Sciences University of Nebraska Lincoln Nebraska 68588 USA

Ectotherms generally demonstrate nonlinear changes in performance （e.g., movement speed, indi- vidual growth, population growth） as a function of temperature that are characterized by thermal performance curves （TPC）. Predation risk elicits phenotypic and behavioral changes that likewise impact performance measures. We tested whether exposure to predation Orthocyclops modestus impacts the maximum population growth rate （rmax） TPC of the protist Paramecium aurelia. We fit predator and non-predator exposed P. aurelia population growth rates to a function previously shown to best describe Paramecium population growth rate TPC＇s （Lactin-2） and compared subse- quent parameter estimates between curves. For Paramecium exposed to predation risk, maximum population growth increased more rapidly as temperatures rose and decreased more rapidly as temperatures fell compared to the initial temperature. The area under each TPC curve remained ap- proximately the same, consistent with the idea of a trade-off in performance across temperatures. Our results indicate TPCs are flexible given variation in food web context and that trophic inter- actions may play an important role in shaping TPCs. Furthermore, this and other studies illustrate the need for a mechanistic model of TPCs with parameters tied to biologically meaningful properties.

关键词： paramecium phenotypic plasticity predation reaction norm temperature thermal performance curve.

Comparison of the demographic characteristics of pediatric and adult colorectal cancer patients: a national inpatient sample based analysis

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World Journal of Pediatrics 2019年第1期15卷 37-41页

作者： thomas m.Attard Caitlin E.Lawson University of missouri Kansas City Kansas CityMOUSA Pediatric Gastroenterology Children's Mercy Hospital2401Gillham RdKansas CityMO 64108USA Division of Genetics Children's Mercy HospitalKansas CityMOUSA

Background Colorectal cancer in children is rare,but characterized by late presentation,unfavorable histology and poor *** factors for colorectal cancer in children overlap with those for adults with greater influence of hereditary *** epidemiology of colon cancer in children is poorly understood;the aim of this study was to characterize and compare the demographics and relevant clinical characteristics of pediatric and adult colon cancer,using a national inpatient *** The AHRQ online resource HCUPnet/KID database was queried for children,under the age of 18 admitted with ICD 9 Cm diagnoses relating to colorectal cancer,at the time of *** comparison,the corresponding diagnoses in adult patients were queried for each successive *** demographics including residential type and median income by zip-code,tumor localization;if recorded,and mean hospital charges were all accrued and *** Inpatient admissions for pediatric colorectal cancer were more likely male (54%),in the 15-17 years age bracket (57%).They were significantly more likely from Southwestern regions of the Unites States,and were significantly more likely from residential zip-codes identified as at or below the lowest income quartile than adult CRC patients or pediatric patients as a *** charges have more than quadrupled over the time period studied (1997-2012).Conclusions Pediatric colorectal cancer is the most common primary gastrointestinal malignancy in *** understanding associated risk factors including those associated with gender,geographic region and social economic status may contribute to future prevention or early detection strategies.

关键词： Colorectal cancer Colorectal neoplasms Demography International classification of diseases Pediatric risk factors