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Blister aneurysms  [PDF]
Journal of Neurological Sciences , 2009,
Abstract: The majority of saccular cerebral aneurysms arise at arterial branchings; those arising elsewhere are rare. Blister aneurysms are elusive and technically challenging rare lesions characterized by a hemispherical shape and fragile walls for both neurosurgeon and endovascular radiologist to treat. Blister aneurysms also exhibit rapid change in size and morphology in followup angiograms. Small size of blood-blister aneurysm and atypical location may result in incomplete visualization of these lesions. Therefore, multiple oblique views are essential during angiography. The weak nature and small size of blister aneurysms with a broad neck renders endovascular treatment technically challenging. Wrapping with cellulose fabric (Bemsheet) and holding clipping technique could be chosen as the optimal surgical modality for prevention of rebleeding from these lesions.
Study of the time and space distribution of beta+ emitters from 80 MeV/u carbon ion beam irradiation on PMMA  [PDF]
C. Agodi,F. Bellini,G. A. P. Cirrone,F. Collamati,G. Cuttone,E. De Lucia,M. De Napoli,A. Di Domenico,R. Faccini,F. Ferroni,S. Fiore,P. Gauzzi,E. Iarocci,M. Marafini,I. Mattei,A. Paoloni,V. Patera,L. Piersanti,F. Romano,A. Sarti,A. Sciubba,C. Voena
Physics , 2012, DOI: 10.1016/j.nimb.2012.04.021
Abstract: Proton and carbon ion therapy is an emerging technique used for the treatment of solid cancers. The monitoring of the dose delivered during such treatments and the on-line knowledge of the Bragg peak position is still a matter of research. A possible technique exploits the collinear $511\ \kilo\electronvolt$ photons produced by positrons annihilation from $\beta^+$ emitters created by the beam. This paper reports rate measurements of the $511\ \kilo\electronvolt$ photons emitted after the interactions of a $80\ \mega\electronvolt / u$ fully stripped carbon ion beam at the Laboratori Nazionali del Sud (LNS) of INFN, with a Poly-methyl methacrylate target. The time evolution of the $\beta^+$ rate was parametrized and the dominance of $^{11}C$ emitters over the other species ($^{13}N$, $^{15}O$, $^{14}O$) was observed, measuring the fraction of carbon ions activating $\beta^+$ emitters $A_0=(10.3\pm0.7)\cdot10^{-3}$. The average depth in the PMMA of the positron annihilation from $\beta^+$ emitters was also measured, $D_{\beta^+}=5.3\pm1.1\ \milli\meter$, to be compared to the expected Bragg peak depth $D_{Bragg}=11.0\pm 0.5\ \milli\meter$ obtained from simulations.
Charged particle's flux measurement from PMMA irradiated by 80 MeV/u carbon ion beam  [PDF]
C. Agodi,G. Battistoni,F. Bellini,G. A. P. Cirrone,F. Collamati,G. Cuttone,E. De Lucia,M. De Napoli,A. Di Domenico,R. Faccini,F. Ferroni,S. Fiore,P. Gauzzi,E. Iarocci,M. Marafini,I. Mattei,S. Muraro,A. Paoloni,V. Patera,L. Piersanti,F. Romano,A. Sarti,A. Sciubba,E. Vitale,C. Voena
Physics , 2012, DOI: 10.1088/0031-9155/57/18/5667
Abstract: Hadrontherapy is an emerging technique in cancer therapy that uses beams of charged particles. To meet the improved capability of hadrontherapy in matching the dose release with the cancer position, new dose monitoring techniques need to be developed and introduced into clinical use. The measurement of the fluxes of the secondary particles produced by the hadron beam is of fundamental importance in the design of any dose monitoring device and is eagerly needed to tune Monte Carlo simulations. We report the measurements done with charged secondary particles produced from the interaction of a 80 MeV/u fully stripped carbon ion beam at the INFN Laboratori Nazionali del Sud, Catania, with a Poly-methyl methacrylate target. Charged secondary particles, produced at 90$\degree$ with respect to the beam axis, have been tracked with a drift chamber, while their energy and time of flight has been measured by means of a LYSO scintillator. Secondary protons have been identified exploiting the energy and time of flight information, and their emission region has been reconstructed backtracking from the drift chamber to the target. Moreover a position scan of the target indicates that the reconstructed emission region follows the movement of the expected Bragg peak position. Exploting the reconstruction of the emission region, an accuracy on the Bragg peak determination in the submillimeter range has been obtained. The measured differential production rate for protons produced with $E^{\rm Prod}_{\rm kin} >$ 83 MeV and emitted at 90$\degree$ with respect to the beam line is: $dN_{\rm P}/(dN_{\rm C}d\Omega)(E^{\rm Prod}_{\rm kin} > 83 {\rm ~MeV}, \theta=90\degree)= (2.69\pm 0.08_{\rm stat} \pm 0.12_{\rm sys})\times 10^{-4} sr^{-1}$.
The mechanism of nucleation of hydrogen blister in metals
XueChong Ren,QingJun Zhou,WuYang Chu,JinXu Li,YanJing Su,LiJie Qiao
Chinese Science Bulletin , 2007, DOI: 10.1007/s11434-007-0269-y
Abstract: The nucleating, growing and cracking of hydrogen blister have been investigated experimentally and theoretically. The results show that atomic hydrogen induces superabundant vacancies in metals. The superabundant vacancies and hydrogen aggregate into a hydrogen-vacancy cluster (microcavity). The hydrogen atoms in the microcavity become hydrogen molecules which can stabilize the cluster. And the hydrogen blister nucleates. With the entry of vacancies and hydrogen atoms, the blister nucleus grows and the pressure in the cavity increases. When the stress induced by hydrogen pressure on the blister is up to the cohesive strength, cracks will initiate from the wall of the blister.
How a Blister Heals  [PDF]
Jonathan E. Longley,L. Mahadevan,Manoj K. Chaudhury
Physics , 2014, DOI: 10.1209/0295-5075/104/46002
Abstract: We use experiments to study the dynamics of the healing of a blister, a localized bump in a thin elastic layer that is adhered to a soft substrate everywhere except at the bump. We create a blister by gently placing a glass cover slip on a PDMS substrate. The pressure jump across the elastic layer drives fluid flow through micro-channels that form at the interface between the layer and the substrate; these channels coalesce at discrete locations as the blister heals and eventually disappear at a lower critical radius. The spacing of the channel follows a simple scaling law that can be theoretically justified, and the kinetics of healing is rate limited by fluid flow, but with a non-trivial dependence on the substrate thickness that likely arises due to channelization. Our study is relevant to a variety of soft adhesion scenarios.
The Liquid Blister Test  [PDF]
J. Chopin,D. Vella,A. Boudaoud
Physics , 2008, DOI: 10.1098/rspa.2008.0095
Abstract: We consider a thin elastic sheet adhering to a stiff substrate by means of the surface tension of a thin liquid layer. Debonding is initiated by imposing a vertical displacement at the centre of the sheet and leads to the formation of a delaminated region, or `blister'. This experiment reveals that the perimeter of the blister takes one of three different forms depending on the vertical displacement imposed. As this displacement is increased, we observe first circular, then undulating and finally triangular blisters. We obtain theoretical predictions for the observed features of each of these three families of blisters. The theory is built upon the F\"{o}ppl-von K\'{a}rm\'{a}n equations for thin elastic plates and accounts for the surface energy of the liquid. We find good quantitative agreement between our theoretical predictions and experimental results, demonstrating that all three families are governed by different balances between elastic and capillary forces. Our results may bear on micrometric tapered devices and other systems where elastic and adhesive forces are in competition.
Karolina Vrande?i?,Dra?enka Jurkovi?,Jasenka ?osi?,Jelena Po?ti?
Poljoprivreda (Osijek) , 2011,
Abstract: The obligate fungi inside the family Albuginaceae are widespread world wide and cause white rust or white blister disease. Mycopopulation of weeds has been researched within the project The role of weeds in epidemiology of row-crop diseases“. The aim of this research was to identify white blister species occurring on weeds in Eastern Croatia. Weed plants with disease symptoms characteristic for white blister species have been collected since 2001 on location Slavonia and Baranja country. Determination of white blister species was based on morphological characters of pathogen and the host. Wilsoniana bliti was determined on Amaranthus retroflexus and Amaranthus hybridus leaves. Capsella bursa pastoris is a host for Albugo candida. Ambrosia artemisiifolia is a host for Pustula sp. and Cirsium arvense was found to be host for Pustula spinulosa. Wilsoniana portulaceae was determined on Portulaca oleracea.
Blister fluid immunofluorescence in a case of pemphigus vulgaris
Shanmugasekar C,Ram Ganesh V,Jayaraman Alamelu,Srinivas C
Indian Journal of Dermatology , 2010,
Abstract: Indirect immunofluorescence with serum is used in the diagnosis of pemphigus. We report a case in whom blister fluid was used as the specimen for indirect immunofluorecscence.
Effect of Microstructures and Material Compositions on Blister Formation  [PDF]
Yunan Prawoto. Jern Phye Tan Tan, Choon Yong Loh
Materials Sciences and Applications (MSA) , 2010, DOI: 10.4236/msa.2010.13025
Abstract: One of the early failures of coating is blister. Here two different coatings were applied on various materials and microstructures. The formation of the blister, and its microstructural and material dependencies were evaluated. It is concluded that general organic coating forms more severe blisters than that of the metallic effect coating. General organic coating protects the samples by insulation film while metallic coating protects by acting as galvanic protection. Therefore, the failure modes are also different, namely blister and filiform corrosion. The dependencies on the microstructures and on material types also follow the insulation film concept and galvanic protection concept.
Naevus depiomentosus treated with suction blister grafting  [cached]
Ravikumar B,Sabitha L,Balachandran C
Indian Journal of Dermatology, Venereology and Leprology , 2000,
Abstract: Naevus depigmentosus is a congenital hypomelanotic condition in which the off white lesions are permanent and cosmetically embarassing. There has been no effective treatment reported so for for this condition. Here we are reporting a patient of naevus depigmentosus on whom we performed suction blister grafting and the resultant pigmentation was satisfactory
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