999 resultados para VOLUME DILATATION


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Breakup process of polyamide 6 (PA6) in polypropylene (PP) matrix under shear flow was online studied by using a Linkam CSS 450 stage equipped with optical microscopy. Both tip streaming and fracture breakup modes of PA6 droplets were observed in this study. It was reported that the droplet would break up by tip streaming model when the radio of the droplet phase viscosity to the matrix phase viscosity (n(r) = n(d)/n(m)) is smaller than 0.1 (Taylor, Proc R Soc London A 1934, 146, 501; Grace, Chem Eng Commun 1982, 14, 225; Bartok and Mason, J Colloid Sci 1959, 14, 13; Rumscheidt and Mason, J Colloid Sci 1961, 16, 238; de Bruijn, Chem Eng Sci 1993, 48, 277). However, the tip streaming model was observed even when the viscosity ratio was much greater than 0.1 (n(r) = 1.9). In this study for the tip streaming mode, small droplets were ruptured from the tip of the mother droplet. On the other hand, the mother droplet was broken into two or more daughter droplets with one or several satellite droplets between them for the fracture mode. It was found that PA6 droplet was much elongated at first, and then broke up via tip streaming or fracture to form daughter droplets or small satellite droplets with the shape of fiber or ellipse.

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Pulmonary emphysema causes decrease in lung function due to irreversible dilatation of intrapulmonary air spaces, which is linked to high morbidity and mortality. Lung volume reduction (LVR) is an invasive therapeutical option for pulmonary emphysema in order to improve ventilation mechanics. LVR can be carried out by lung resection surgery or different minimally invasive endoscopical procedures. All LVR-options require mandatory preinterventional evaluation to detect hyperinflated dysfunctional lung areas as target structures for treatment. Quantitative computed tomography can determine the volume percentage of emphysematous lung and its topographical distribution based on the lung's radiodensity. Modern techniques allow for lobebased quantification that facilitates treatment planning. Clinical tests still play the most important role in post-interventional therapy monitoring, but CT is crucial in the detection of postoperative complications and foreshadows the method's high potential in sophisticated experimental studies. Within the last ten years, LVR with endobronchial valves has become an extensively researched minimally-invasive treatment option. However, this therapy is considerably complicated by the frequent occurrence of functional interlobar shunts. The presence of "collateral ventilation" has to be ruled out prior to valve implantations, as the presence of these extraanatomical connections between different lobes may jeopardize the success of therapy. Recent experimental studies evaluated the automatic detection of incomplete lobar fissures from CT scans, because they are considered to be a predictor for the existence of shunts. To date, these methods are yet to show acceptable results. KEY POINTS Today, surgical and various minimal invasive methods of lung volume reduction are in use. Radiological and nuclear medical examinations are helpful in the evaluation of an appropriate lung area. Imaging can detect periinterventional complications. Reduction of lung volume has not yet been conclusively proven to be effective and is a therapeutical option with little scientific evidence.

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AIMS: Limited data are available concerning the evolution of the left atrial volume index (LAVI) in pre-heart failure (HF) patients. The aim of this study was to investigate clinical characteristics and serological biomarkers in a cohort with risk factors for HF and evidence of serial atrial dilatation.

METHODS AND RESULTS: This was a prospective substudy within the framework of the STOP-HF cohort (NCT00921960) involving 518 patients with risk factors for HF electively undergoing serial clinical, echocardiographic, and natriuretic peptide assessment. Mean follow-up time between assessments was 15 ± 6 months. 'Progressors' (n = 39) were defined as those with serial LAVI change ≥3.5 mL/m(2) (and baseline LAVI between 20 and 34 mL/m(2)). This cut-off was derived from a calculated reference change value above the biological, analytical, and observer variability of serial LAVI measurement. Multivariate analysis identified significant baseline clinical associates of LAVI progression as increased age, beta-blocker usage, and left ventricular mass index (all P < 0.05). Serological biomarkers were measured in a randomly selected subcohort of 30 'Progressors' matched to 30 'Non-progressors'. For 'Progressors', relative changes in matrix metalloproteinase 9 (MMP9), tissue inhibitor of metalloproteinase 1 (TIMP1), and the TIMP1/MMP9 ratio, markers of interstitial remodelling, tracked with changes in LAVI over time (all P < 0.05).

CONCLUSION: Accelerated LAVI increase was found to occur in up to 14% of all pre-HF patients undergoing serial echocardiograms over a relatively short follow-up period. In a randomly selected subcohort of 'Progressors', changes in LAVI were closely linked with alterations in MMP9, TIMP1, and the ratio of these enzymes, a potential aid in highlighting this at-risk group.

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An unstructured mesh �nite volume discretisation method for simulating di�usion in anisotropic media in two-dimensional space is discussed. This technique is considered as an extension of the fully implicit hybrid control-volume �nite-element method and it retains the local continuity of the ux at the control volume faces. A least squares function recon- struction technique together with a new ux decomposition strategy is used to obtain an accurate ux approximation at the control volume face, ensuring that the overall accuracy of the spatial discretisation maintains second order. This paper highlights that the new technique coincides with the traditional shape function technique when the correction term is neglected and that it signi�cantly increases the accuracy of the previous linear scheme on coarse meshes when applied to media that exhibit very strong to extreme anisotropy ratios. It is concluded that the method can be used on both regular and irregular meshes, and appears independent of the mesh quality.

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President’s Report Hello fellow AITPM members, Welcome to the first edition of the AITPM National Newsletter for 2009! I trust we all had a relaxing break and managed to lose track of all things transport for just a little while. I know I had trouble doing so when hunting for a car space at the shopping centre, and experiencing new projects such as the Tugun Bypass – the new gateway between New South Wales and Queensland. Byron Bay is now as close as Noosa for those high profile beach goers of Brisbane. There was also my experience of the reduced posted speed of 90km/h on the Bruce Highway around the troublesome Gympie stretch, when returning from a short Fraser Coast holiday. I expect that this relatively inexpensive safety improvement will pay substantial dividends in terms of crash reduction. The Newsletter took its annual leave last month and is refreshed and ready for a new year to keep us all informed of the latest in traffic and transport engineering, planning and management. I would like to take this opportunity to acknowledge the ongoing significant contributions of many volunteers in the Newsletter’s production. Mr Andrew Hulse, AITPM’s Immediate Past National President, serves as the Editorial Coordinator on behalf of the Institute. Each Branch Committee also includes a Newsletter Coordinator and committee members frequently contribute as well. And the ongoing contributions of readers enable us to offer the Newsletter as a vehicle for dialogue and debate around our sector. If you would like to contribute please email AITPM’s administration officer Josephine Mitton at aitpm@aitpm.com or through your local Branch Committee. I would also like to welcome back on deck our Editor, Mr David Brown of Driven Media, who creates a fantastic package for us each month. Lastly, members would have received the Call for Papers for the AITPM 2009 National Conference, Traffic Beyond Tomorrow, to be held at the Adelaide Convention Centre between 5 – 7 August. Abstracts will be accepted up to 20 February 2009. We look forward to seeing everyone at this, our flagship event for the year. To all a good year ahead, Jon Bunker Post Script: We all will have seen through the media the enormous scale and nature of the two natural disasters Australia is experiencing at present. AITPM’s thoughts are with all of those members, family and friends who may be experiencing hardship as a result of the Victorian bushfires and North Queensland floods. AITPM is a not for profit organisation however the National Executive has taken the decision to donate in measure to the Red Cross Victorian Bushfire Disaster Relief fund and the Queensland Premier’s Disaster Relief fund as a gesture to support our fellow Australians in their time of need. Details about these funds can be found via the Victorian and Queensland Governments’ websites.

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President’s Report Hello fellow AITPM members, First I would like on behalf of all AITPM members to send our condolences to all who have been affected by February’s tragic bushfires in regional Victoria, and deliver our best wishes to all of those involved in the rebuilding efforts. Over time I expect that the Victorian Government’s Royal Commission will analyse the circumstances and put forward a range of measures which will improve fire safety in vulnerable areas. As transport professionals it will be important for us to consider the findings and look to undertaking any recommendations that relate to the work we do. Not only in Victoria, but nationwide. In particular, the importance of logistics was highlighted following the fire events. Donors across Australia were this time requested to donate money rather than goods, presumably due in part to problems associated with the transport system coping with additional uncoordinated freight load, whilst being needed to support emergency management vehicle and managed freight movements. Notwithstanding, it was wonderful to see otherwise difficult to obtain goods, such as animal feed, being donated from far afield and transported in kind by trucking operators. As stated in last month’s Newsletter, AITPM made a direct cash donation to the Red Cross Bushfire Appeal immediately following the events, and a further donation to the Queensland Premier’s Disaster Relief Fund to support recovery after the North Queensland floods, which claimed seven lives. Again, we will need to monitor how the rebuilding effort unfolds particularly in regional Victoria and centres including Ingham in North Queensland, but I would urge all AITPM members who are in a position to support the restoration of the affected communities to play a part, particularly over time once the initial shock subsides and the steady job of rebuilding is underway. Onto lighter matters, AITPM’s flagship event, the 2009 AITPM National Conference, Traffic Beyond Tomorrow, being held in Adelaide from 5 to 7 August, is fast approaching. www.aitpm.com has all of the details about how to register, sponsor a booth, and so forth. We are looking forward to catching up with our conference “regulars” and meeting with new folks to AITPM, and Australian traffic and transport planning and management. Adelaide is one of my favourite places to visit and I’m looking forward to riding the light rail line extension through town and checking out progress on the road system development. Best regards all, Jon Bunker

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President’s Report Hello fellow AITPM members, A few weeks ago we saw another example of all levels of Government pulling together in real time to try to deal with a major transport incident, this time it was container loads of ammonium nitrate falling off the Pacific Adventurer during Cyclone Hamish and the associated major oil spill due to piercing of its hull off Moreton Bay in southern Queensland. The oil spill was extensive, affecting beaches and estuaries from Moreton Island north to the Sunshine Coast; a coastal stretch of at least 60km. We saw the Queensland Government, Brisbane, Moreton Bay and Sunshine Coast Regional Council crews deployed quickly once the gravity of the situation was realised to clean up toxic oil on beaches and prevent extensive upstream contamination. Environmental agencies public and private were quick to respond to help affected wildlife. The Navy’s HMAS Yarra and another minesweeper were deployed to search for the containers in the coastal area in an effort to have them salvaged before all ammonium nitrate could leach into and harm marine habitat, which would have a substantial impact not only on that environment but also the fishing industry. all of this during the final fortnight before a State election.) While this could be branded as a maritime problem, the road transport and logistics system was crucial to the cleanup. The private vehicular ferries were enlisted to transport plant and equipment from Brisbane to Moreton Island. The plant themselves, such as graders, were drawn from road building and maintenance inventory. Hundreds of Councils’ staff were released from other activities to undertake the cleanup. While it will take some time for us to know the long term impacts of this incident, it seems difficult to fault “grassroots” government crews and their private counterparts, such as Island tourism staff, in the initial cleanup effort. From a traffic planning and management perspective, we should also remember that this sort of incident has happened on road and rail corridors in the past, albeit on lesser scales. It underlines that we do need to continue to protect communities, commercial interests, and the environment through rigorous heavy vehicle management, planning and management of dangerous goods routesincluding rail corridors through urban areas), and carefully considered incident and disaster recovery plans and protocols. I’d like to close in reminding everyone again that AITPM’s flagship event, the 2009 AITPM National Conference, Traffic Beyond Tomorrow, is being held in Adelaide from 5 to 7 August. SA Branch President Paul Morris informs me that we have had over 50 paper submissions to date, from which a very balanced and informative programme of sessions has been prepared. www.aitpm.com has all of the details about how to register, sponsor a booth, session, etc. Best regards all, Jon Bunker

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President’s Message Hello fellow AITPM members, We’ve been offered a lot of press lately about the Federal Government’s plan for the multibillion dollar rollout of its high speed broadband network, which at the moment is being rated to a speed of 100Mb/s. This seems fantastic in comparison to the not atypical 250 to 500kb/s that I receive on my metropolitan cable broadband, which incidentally my service provider rates at theoretical speeds of up to 8 Mb/s. I have no doubt that such a scheme will generate significant advantages to business and consumers. However, I also have some reservations. Only a few of years ago I marvelled at my first 256Mb USB stick, which cost my employer about $90. Last month I purchased a 16Gb stick with a free computer carry bag for $80, which on the back of my envelope has given me about 72 times the value of my first USB stick not including the carry bag! I am pretty sure the technology industry will find a way to eventually push a lot more than 100Mb/s down the optic fibre network just as they have done with pushing several Mb/s ADSL2 down antique copper wire. This makes me wonder about the general problem of inbuilt obsolescence of all things high-tech due to rapid advances in the tech industry. As a transport professional I then think to myself that our industry has been moving forward at somewhat of a slower pace. We certainly have had major milestones having significant impacts, such as the move from horse and cart to the self propelled motor vehicle, sealing and formal geometric design of roads, development of motorways, signalisation of intersections, coordination of networks, to simulation modelling for real time adaptive control (perhaps major change has been at a frequency of 30 years or so?). But now with ITS truly penetrating the transport market, largely thanks to the in-car GPS navigator, smart phone, e-toll and e-ticket, I believe that to avoid our own obsolescence we’re going to need to “plan for ITS” rather than just what we seem to have been doing up until now, that is, to get it out there. And we’ll likely need to do it at a faster pace. It will involve understanding how to data mine enormous data sets, better understanding the human/machine interface, keeping pace with automotive technology more closely, resolving the ethical and privacy chestnuts, and in the main actually planning for ITS to make peoples’ lives easier rather than harder. And in amongst this we’ll need to keep pace with the types of technology advances similar to my USB stick example above. All the while we’ll be making a brand new set of friends in the disciplines that will morph into ITS along with us. Hopefully these will all be “good” problems for our profession to have. I should close in reminding everyone again that AITPM’s flagship event, the 2009 AITPM National Conference, Traffic Beyond Tomorrow, is being held in Adelaide from 5 to 7 August. www.aitpm.com has all of the details about how to register, sponsor a booth, session, etc. Best regards all, Jon Bunker

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President’s Message Hello fellow AITPM members, Due to three colliding forces of nature I find myself writing this month’s message from home – today, I am still getting over a persistent virus that seemed to set in just after returning from Singapore a couple of weeks ago, which my diabetes won’t let me get away with too easily (no Kermit the Frog swine flu jokes please). Combine this with a very wet day in Brisbane – in fact the wettest for 20 years (how can we complain, except for flash flooding?). And in Queensland today is a state school teachers’ strike, so one half of our brood is over watching TV. Family snapshots aside, the biggest news for our industry of late is the $8.5 billion announced in the Federal Budget for transport infrastructure projects; many “shovel ready”, but some – and fortunate for our profession – desktop ready. This newsletter provides nationwide coverage on the transport infrastructure aspects of the Federal Budget. We’ll need a bit more time to carefully look at the ensuing State Budgets’ announcements. Regarding the federal budget announcements, I am pleased to see serious attention being paid to upgrading the M1 system – I hope to see a motorway standard facility connecting Adelaide to at least Rockhampton in my lifetime. But some other important roads are of course missing out in this particular budget. Various levels of commitment are being made to urban passenger rail – some project significant while others planning significant. Enhancement of suburban rail is important across the capitals and Australia’s medium sized cities such as the Gold Coast and Newcastle. Not much on road safety initiatives jumped out at me, but I believe it is implied in the large road projects and in some of the detail elsewhere. I do believe it’s about time a ‘Vision Zero’ style policy is adopted at the National level, since any death is unacceptable on the road, just as it is in any other workplace. So, overall some good news on building transport infrastructure to keep the economy purring during this recession, and strongly supporting it during future boom times. The other edge to the sword, of course, is that we tax payers will be paying a considerable amount for borrowings for these projects over a long period of time. I close again in reminding everyone again that AITPM’s flagship event, the 2009 AITPM National Conference, Traffic Beyond Tomorrow, is being held in Adelaide from 5 to 7 August. www.aitpm.com has all of the details about how to register, sponsor a booth, session, etc. Best regards all, Jon Bunker