196,456 research outputs found
Computer modelling of multiple tee-beam bridges
No full textBridges consisting of multiple parallel pre-stressed and pre-fabricated Tee-beams topped by a cast-on-site concrete slab are often a cost-effective way of constructing simply-supported and multi-span bridge structures in many countries world-wide. For the design of these bridges computer models are often utilised. This thesis presents a comprehensive discussion of modelling issues encountered in the practical design work on this bridge type. A chapter on the modelling of various loading conditions is followed by a detailed discussion of the modelling of the longitudinal load bearing system, the Tee-beams, and the lateral load-bearing system, the roadway slab. A summary of commonly used bridge systems in various countries is also included. All this material is presented considering design code requirements in various internationally used specifications. The information included in this thesis has been used to define specifications for the implementation of a software tool to support the design of so-called Super-Tee bridges. A summary of these specifications is given in the conclusions of this thesis. Material included in this thesis has also been published in the following conference proceedings: Pircher G., Pircher M. (2004) “Computer-aided design and analysis of multiple Tee-beam bridges”, Proceedings: Fifth Austroads Bridge Conference, Hobart, Australia, on CD Pircher M, Pircher G, Wheeler A (2006) “Automated Analysis and Design of Super-Tee Bridges”, Proceedings: Sixth Austroads Bridge Conference, Perth (in publication
Myocardial Ischemia and Reperfusion Leads to Transient CD8 Immune Deficiency and Accelerated Immunosenescence in CMV-Seropositive Patients
No full textRationale: There is mounting evidence of a higher incidence of coronary heart disease (CHD) in cytomegalovirus (CMV) seropositive individuals.
Objective: The aim of this study was to investigate whether acute MI triggers an inflammatory T-cell response that might lead to accelerated immunosenescence in CMV-seropositive patients.
Methods and Results: Thirty-four patients with acute MI undergoing primary PCI (PPCI) were longitudinally studied within 3 months following reperfusion (Cohort A). In addition, 54 patients with acute and chronic MI were analyzed in a cross-sectional study (Cohort B). CMV-seropositive patients demonstrated a greater fall in the concentration of terminally differentiated CD8 effector memory T cells (TEMRA) in peripheral blood during the first 30 min of reperfusion compared with CMV-seronegative patients (-192 vs. -63 cells/µl; p=0.008), correlating with the expression of programmed cell death-1 (PD-1) before PPCI (r=0.8; p=0.0002). A significant proportion of TEMRA cells remained depleted for at least 3 months in CMV-seropositive patients. Using high-throughput 13-parameter flow cytometry and HLA class I CMV-specific dextramers, we confirmed an acute and persistent depletion of terminally differentiated TEMRA and CMV-specific CD8+ cells in CMV-seropositive patients. Long-term reconstitution of the TEMRA pool in chronic CMV-seropositive post-MI patients was associated with signs of terminal differentiation including an increase in KLRG1 and shorter telomere length in CD8+ T cells (2225 bp vs. 3397 bp; p<0.001).
Conclusions: Myocardial ischemia and reperfusion in CMV-seropositive patients undergoing PPCI leads to acute loss of antigen-specific, terminally differentiated CD8 T-cells, possibly through PD-1-dependent programmed cell death. Our results suggest that acute MI and reperfusion accelerate immunosenescence in CMV-seropositive patients
Rischi sanitari legati al ripolamento delle acque interne: Triaenoforosi e Cistidicolosi
No full textNel corso del biennio 2005-2006 si è assistito all’introduzione di due specie parassitarie che
non risultavano fino ad allora descritte sul territorio nazionale, Triaenophorus crassus
(Cestoda: Triaenophoridae) e Cystidicola farionis (Nematoda: Cystidicolidae) in popolazioni
di salmonidi presenti nelle acque pubbliche dell’Alto-Adige.
Per quanto riguarda T. crassus, dopo che la sua presenza era stata segnalata nel 2005 in
coregoni (Coregonus spp.) di un lago della provincia di Bolzano, successive indagini
parassitologiche hanno permesso di individuarne la presenza in tutti gli ospiti coinvolti nel
suo ciclo biologico: Esox lucius quale ospite definitivo, alcune specie di salmonidi (coregoni e
Salmo trutta m. fario) come secondi ospiti intermedi e crostacei copepodi quali primi ospiti
intermedi, indicando una stabile colonizzazione del parassita nell’ecosistema in studio.
In riferimento al nematode C. farionis, rinvenuto per la prima volta nel 2006 da un pescatore
non professionista in trote iridee (Oncorhynchus mykiss) pescate in un corso d’acqua in
prossimità di Merano (BZ), indagini parassitologiche hanno permesso di individuare questo
parassita, fino ad allora descritto solo in Europa settentrionale, Asia e Nord America, in
diverse specie ittiche nostrane. In particolare, prevalenze elevate (80,8%) con intensità
d’infestazione fino a 100 parassiti/ospite sono state osservate nella trota iridea, mentre la trota
fario (S. trutta m. fario) e la trota marmorata (S. trutta m. marmoratus) sono risultate positive
con valori di prevalenza ed intensità d’infestazione nettamente inferiori. Sono tuttora in corso
le ricerche sugli ospiti intermedi, rappresentati da crostacei anfipodi, per valutare la possibilità
che il ciclo biologico si sia già instaurato con successo negli ambienti acquatici in studio.
Le osservazioni istopatologiche condotte in coregoni parassitati da T. crassus e trote iridee
infestate da C. farionis hanno permesso di rilevare evidenti alterazioni patologiche a carico,
rispettivamente, di tessuto muscolare e vescica natatoria, soprattutto in correlazione ad elevate
intensità di infestazione. Va poi evidenziato come, oltre all’effetto patogeno diretto
sull’ospite, questi parassiti possano influenzare negativamente le dinamiche di popolazione in
natura e, soprattutto nel caso di T. crassus, causare un notevole deprezzamento del valore
commerciale del prodotto ittico, fino alla sua esclusione dal mercato.
Il rinvenimento di queste due nuove parassitosi a carico di popolazioni di salmonidi presenti
in sistemi idrici nazionali pone in evidenza la necessità di associare una corretta analisi
parassitologica agli esami sanitari già prescritti dalla normativa vigente per le attività di
semina in acque pubbliche, onde evitare l’introduzione di patogeni parassitari difficilmente
eradicabili qualora si dovesse verificare la loro stabile colonizzazione nell’ecosistema
acquatico, come già dimostrato per T. crassus. Resta inoltre di fondamentale importanza la
sensibilizzazione ed il coinvolgimento delle associazioni di pesca sportiva, in quanto dai dati
in nostro possesso la causa più probabile dell’introduzione di queste due specie parassitarie
sarebbe da riferire ad attività di ripopolamento non autorizzate con pesci infestati provenienti dall'ester
Dr. Duane M. Jackson, Morehouse College, July 2011
No full textThis video is a conversation with Dr. Duane M. Jackson. Dr. Jackson talks about his paper, "Recall and the Serial Position Effect: The Role of Primacy and Recency on Accounting Students' Performance." Jackie Daniel, AUC Woodruff Library, is the interviewer
"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States" By M. Carey.
No full text"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States: containing bried sketches of the moral and political character of those states.
By M. Carey, member of the American philosophical, and of the American Antiquarian Society, and author of The Olive Branch, Cindiciae Hibernicae, essays on banking, on political economy, and on internal improvement.
To which are now added the English editor's comments on the subject; together with Important Advice to Emigrants, and Cautions Against Impositions Practiced in the Outports
Plerocercosi da Triaenophorus crassus (Cestoda, Pseudophyllidea) in coregoni (Coregonus spp.): primi riscontri in Italia
No full textDispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Dr. Glendon Swarthout
No full textHosted by Roger M. Busfield, MSU Assistant Professor of Speech and Theater, Meet the Author is designed to introduce a general audience to a contemporary author and their work through in-depth interviews. This episode features a conversation between Dr. Glendon Swarthout, prolific author and English professor at MSU, and assistant professors Sam S. Baskett and Theodore B. Strandness
Optical Coherence Tomography for Examination of Parchment Degradation
No full textA novel application of Optical Coherence Tomography utilizing infrared light of 830 nm central wavelength for non invasive examination of the structure of parchment, some covered with iron gall ink, is presented. It is shown that both the parchment and the ink applied are sufficiently transparent to light of this wavelength. In the study, Spectral OCT (SOCT) as well as Polarisation Sensitive OCT (PS-OCT) techniques were used to obtain cross-sectional images of samples of parchment based on scattering properties. The second technique was additionally employed to recover the birefringence properties and the optical axis orientations of the sample. It was shown that freshly produced parchment exhibits a degree of birefringence. However, this property declines with ageing, and samples of old parchment completely depolarise the incident light
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