6,373 research outputs found
Desperately Seeking Skopas
No full textIn America today, opinion has turned decisively against the resurrection of artistic personalities from Greek antiquity. After investigating why scholars have taken this extreme position, this paper attempts to counter it both methodologically and philologically, then examines what we know about Skopas and his oeuvre. In particular, how do we explain his frequent appearance alongside Praxiteles in the sources, their disputes over attribution included? I then discuss some individual works, offering new or overlooked evidence for their date and attribution, and finally present a new reconstruction and evaluation of the Tegea temple’s interior, based on recent work at Tegea by Jari Pakkanen
Population prevalence, incidence, and predictors of atrial fibrillation in the Renfrew/Paisley study
No full text<b>OBJECTIVES</b> Though atrial fibrillation (AF) is an important cause of cardiovascular morbidity, there are few large epidemiological studies of its prevalence, incidence, and risk factors. The epidemiological features of AF are described in one of the largest population cohorts ever studied.
<b>METHODS</b> The prevalence and incidence of AF were studied in the Renfrew/Paisley population cohort of 15 406 men and women aged 45-64 years living in the west of Scotland. This cohort was initially screened between 1972 and 1976 and again between 1977 and 1979. Incident hospitalisations with AF in the 20 year period following initial screening were also studied.
<b>RESULTS</b> The population prevalence of AF in this cohort was 6.5 cases/1000 examinations. Prevalence was higher in men and older subjects. In those who were rescreened, the four year incidence of AF was 0.54 cases/1000 person years. Radiological cardiomegaly was the most powerful predictor of new AF (adjusted odds ratio 14.0). During 20 year follow up, 3.5% of this cohort was discharged from hospital with a diagnosis of AF; the rate of incident hospitalisation for AF was 1.9 cases/1000 person years. Radiological cardiomegaly (adjusted odds ratio 1.46) and systolic blood pressure (adjusted odds ratio 2.1 for ≥ 169 mm Hg) were independent predictors of this outcome.
<b>CONCLUSIONS</b> Data from one of the largest epidemiological studies ever undertaken confirm that AF has a large population prevalence and incidence, even in middle aged people. More important, it was shown that the long term incidence of hospitalisation related to AF is high and that two simple clinical measurements are highly predictive of incident AF. These findings have important implications for the prevention of AF
Design of Stewart Platform for Wave Compensation
No full textDette kandidat speciale er skrevet i foråret 2012 i forbindelse med afslutningen af civilingeniøruddannelsen inden for 'Elektro-Mekanisk System Design' på Aalborg Universitet. Specialet omhandler design metode, forståelse og optimering af en Stewart platform til kompensering af bølgebevægelsers påvirkning af skibskraner. Projektet er udarbejdet i samarbejde med HYDAC A/S, en større producent indenfor hydraulik komponenter, som har ønsket et dybere kendskab til Stewart platformen, dens kinematik og dimensionerende faktorer. HYDAC A/S har derfor stillet projektforslaget om Stewart platformens brug til bølgekompensering af skibskraner.Skibskraner bruges ikke kun til at laste og losse i rolige havnemiljøer, men bruges også til offshore operationer og begrænses derved af de aktuelle havforhold, da bølgepåvirkninger af kranfartøjet kan forårsage store svingninger i kranlasten. Dette sker selv i forholdsvis roligt vejr med bølgehøjder ned til under 1 m \cite{schaub}, og søgangen kan dermed let udsætte arbejdsopgaver og koste operatøren penge. Det ønskes derfor at designe en Stewart platform som skal fungere som stabilt fundament for kranen, så svingningerne i kranen minimeres.Det initierende problem for projektet er derfor defineret som:Hvordan designes en Stewart platform optimalt til bølgekompensering?En Stewart platform er en seksbenet parallel robot med 6 frihedsgrader. Dette er optimalt til bølgekompensering, da skibsbevægelser netop har 6 frihedsgrader og Stewart platformen har dermed potentiale til at kompensere for den totale skibsbevægelse. Yderligere har Stewart platformen den fordel, at den kan yde store kræfter, da der er 6 hydrauliske cylindere til at aktuere den samme platform. Dermed kan den også opnå stor positioneringsnøjagtighed, da en positionsfejl på en cylinder ikke akkumuleres i robotten som tilfældet er for serielle robotter.Stewart platformen er et komplekst kinematisk system, hvor fordele og ulemper ved et givent design kan være svære at gennemskue. Derfor er en dybdegående teoretisk gennemgang af kinematikken og dens performance kriterier samlet i dette speciale. Ud fra gennemgangen kan relevante kriterier udvælges til det ønskede design. Det vælges, at designe Stewart platformen ud fra et krav om 'dexterity', hvilket beskriver robottens evne til at arbejde med ens kræfter og hastigheder i alle retninger og orienteringer. Yderligere er der for at sikre et realiserbart design af Stewart platformen opstillet en række designkrav der skal tages højde for i designprocessen. Disse skal bl.a. sikre, at de hydrauliske cylindre ikke kolliderer indenfor arbejdsområdet og at aktuatorerne til systemet udnyttes optimalt. For at udregne et optimalt design ift. 'dexterity' og indenfor de givne designrammer, opstilles et optimeringsproblem som løses vha. en ' Sequential Quadratic Programming' (SQP) algoritme. Der bestemmes en optimal løsning for den almindelige Stewart Platform og et modificeret design kaldet den koncentriske cickel Stewart platform. Det viser sig, at der ved brug af det modificerede design kan opnås 13.55 % bedre 'dexterity', hvorfor dette design anses som det bedste til bølgekompensering. Oversigten over performance index er universel for både serielle og paralle robot-typer og kan dermed anvendes generelt for robot design. Desuden er hele den angivne designprocedure overførbar til Stewart platforme til andre applikationer.Afslutningsvis dimensioneres udvalgte hydrauliske komponenter til det optimerede Stewart platform design, samt opstilles en fuld simuleringsmodel af det hydrauliske og mekaniske system. For at bestemme de maksimale kræfter, hastigheder, flow samt effekt i systemet, opstilles endnu flere optimeringsproblemer. Dette gøres da systemkræfterne og bevægelserne er funktioner af mange variable. En optimering har bl.a. beregnet at systemets maksimale effekt ved bølgekompensering er 155 kW. Det kan fra det ovenstående konkluderes, at den endelige Stewart platform opfylder alle designkrav. Desuden kan der fra HYDACs Stewart platform prototype opnås en 59 % forbedring i 'dexterity' til single cirkle designet og yderligere 13.5 % til koncentrisk cirkle designet.Ship mounted cranes has a limited workability on the seas due to wave exited pendulation of the hoisted load. This poses a problem as crane operations are aborted and time is lost. The motion of ships and the pendulation of the hoisted load can be counteracted by a Stewart platform due to its 6 DOF motion capacity. The Stewart platform is a complex parallel manipulator which kinematics is difficult to design by hand. The design procedure involves selecting the type of Stewart platform, creating a design capable of generating forces and velocities in all direction, ensure the prescribed workspace can be reached, and many physical constraints on the design. To solve these problems a thorough theoretical review of kinematics and kinematic performance indices are included in this thesis. Mathematical optimization using Sequential Quadratic Programming (SQP) is used to create the best design for wave compensation. Methods of ensuring feasible actuator relations and avoidance of leg collision are developed and are incorporated into the optimization of kinematic performance indices. All methods described can equally be used for other applications than wave compensation. Two types of Stewart platforms are selected and optimized to find that the traditional type is inferior to a slightly more complex type. The more complex type is smaller and has 13.5 % better dexterity. The demands for a hydraulic actuation system are determined using optimization methods, and finally a complete simulation model of the hydraulic and mechanical system is derived.<br/
Isrogrogidda Falka Af-soomaaliga: Aragti ku aadan Midaynta Qoraalkiisa
No full textQoraagu wuxuu diraasad ku sameeyey sidii loo midayn lahaa af Soomaaliga qoraaal ahaan loo adeegsada. Gaar ahaan wuxuu diiradda saarayaa sidii loo midayn lahaa qaababka isrogrogga falalka oo haatan loo adeegsado siyaabo aan midaysanayn.In questo articolo, l'autore analizza e avanza una proposta relativamente alla standardizzazione del somalo scritto, in particolar modo delle forme di coniugazione dei verbi somali che attualmente non sono scritte in modo omogenea.In this article, the author analyzes and provides a proposal about the standardization of written Somali, in particular relating to verb conjugation forms whose orthography still differs today.Cabdirashid M. Ismaaciil, Cabdalla C. Mansuur, Saynab A. Sharci (eds.
Coastal Research and its Economic Justification
No full textProper and thorough planning of coastal engineering projects is discussed and the economie justification of research work indicated. Examples are given concerning navigational problems, coastal protection problems, and harbor sediment problems.KWP-collectio
Progression to macula-off tractional retinal detachment after a contralateral intraoperative intravitreal bevacizumab injection for proliferative diabetic retinopathy
No full textMichael W Stewart, Michael L Stewart Department of Ophthalmology, Mayo Clinic, Jacksonville, FL, USA In a recent edition of Clinical Ophthalmology, Zlotcavitch et al presented a case of progressive diabetic traction retinal detachment in the fellow eye 1 week after vitrectomy with intravitreal bevacizumab.1 This interesting observation extends previous original work by the same authors in which proliferative diabetic retinopathy was noted to regress following a bevacizumab injection into the fellow eye.2 Several points pertaining to this thought-provoking report deserve further discussion. Read the original article 
Screening for atrial fibrillation within a South Asian community setting using single-lead ECG
No full textTimely detection and treatment of AF is amongst the Government’s cardiovascular priorities. Several initiatives have demonstrated the potential of AF detection using single-lead electrocardiogram (SLECG) technology in primary care settings, such as general practitioners’ (GP) surgeries. Unfortunately, some AF patients, including those from ethnic minorities, may not routinely engage with main-stream healthcare and may go undetected. Compared to White British, South Asians have a higher prevalence of cardiovascular risk factors, however fewer are diagnosed with AF. This study aimed to ascertain the feasibility of opportunistic AF screening within a South Asian community delivered by supervised pharmacy undergraduates using SL-ECG devices
Midaynta iyo Horumarinta Af-soomaaliga
No full textQoraagu wuxuu maqaalkan ku falanqaynayaa arrimo ku saabsan midaynta af Soomaaliga qoran, oo dadka qaarkood ay ku doodaan in ay dhibaato ka taagantahay, iyagoo u aanaynaya kala duwanaanta lahjadaha Soomaaliyeed iyo farta af Soomaaliga oo aan xasillayn. Qoraha oo soo bandhigayaa in arrimahaasu aanu sax ahayn, wuxuuna muujinayaa caqabadaha dhabta ah ee hortaagan houmarinta af Soomaaliga: afku wuxuu la'yahay dawlad si rasmi ah u adeegsato, weerar ba'anna waxaa ku haya af Ingiriisiga, xagga ereyadana nabaadguur xooggan ayaa ku dhacaya, gaar ahaan ereyada la xiriira dhaqanka Soomaaliyeed.L'autore, in questo articolo, analizzando la questione della lingua somala scritta, cerca di illustrare che la situazione del somalo standard non è cosi problematica come a detta di alcuni somali, specialmente, nell'ortografia e nella differenza tra i dialetti, ma il problema somalo è bensì riscontrabile in altri fattori: la mancanza di un stato che continui ad adottare il somalo come lingua ufficiale, l'estinzione di tantissimi vocaboli in disuso, nonché la forte influenza dalla lingua inglese.The author in this article, in analysing the written somali language, wants to show the somali standard situation is not so bad, like some Somalis say, especially in orthography and in vernaculars difference. In spite of, the somali language problem is recognisable in some others factors: lack of state that usually chooses somali language as official language, extinction of many terms in disuse and also the strong influence of English.Cabdirashid M. Ismaaciil, Cabdalla C. Mansuur, Saynab A. Sharci (eds.
Synthetic and partially-purified adenylate cyclase-stimulating proteins from tumors associated with humoral hypercalcemia of malignancy inhibit phosphate transport in a PTH-responsive renal cell line.
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Om inloppet ifrån Östersjön : till SöderTelje eller Egelsta wiken
No full textAuthor: Nathanael Gerhard af Schultén.Dated: "Carlberg den 12 Januari 1806."Digital reproduction, The National Library of Finland, Centre for Preservation and Digitisation, MikkeliA description of the Baltic Sea.TravelEuropeanaSchultén, Nathanael Gerhard af (1750-1825
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