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1
Fox, David M. "Bolted joint studies in GRP." Thesis, Monterey, California. Naval Postgraduate School, 1994. http://hdl.handle.net/10945/25716.
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Glass-reinforced polymeric (GRP) materials offer certain advantages to the designer of Naval ships. A large strength-to-weight ratio, coupled with electromagnetic transparency and (possibly engineered) sound-dampening properties, render GRP materials as attractive materials for ship decks and deckhouse skins. Unfortunately, these materials, which use a thermosetting resin as a matrix material, cannot be welded as steel can. Thus, if a large structure is to be built of GRP, the inevitable joints must be either adhesively bounded or mechanically fastened. These joining techniques are frequently combined in joints which must support large loads. Because of this, an understanding of the mechanical behavior of joints in GRP is important
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Fox, David M. (David Michael). "Bolted joint studies in GRP." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/37524.
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Thesis (Nav. E.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 1994, and Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Materials Sciences & Engineering, 1994.Vita.
Includes bibliographical references (leaves ).
by David M. Fox.
M.S.
Nav.E.
3
McKillop, Jane Marie. "Studies with GRP and related peptides." Thesis, Queen's University Belfast, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.356949.
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Hoffman, Timothy Joseph. "GRP receptor specific analogues of bombesin /." free to MU campus, to others for purchase, 1996. http://wwwlib.umi.com/cr/mo/fullcit?p9924958.
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Flaherty, Annette E. "Support of GRP vessels : a comparative study for the horizontal support of laminate construction GRP storage vessels." Thesis, University of Strathclyde, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366892.
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Hartshorn, Robert T. "The mechanical behaviour of cylindrical GRP panels." Thesis, Aston University, 1987. http://publications.aston.ac.uk/11895/.
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Glass reinforced plastic (GRP) is now an established material for the fabrication of sonar windows. Its good mechanical strength, light weight, resistance to corrosion and acoustic transparency, are all properties which fit it for this application. This thesis describes a study, undertaken at the Royal Naval Engineering College, Plymouth, into the mechanical behaviour of a circular cylindrical sonar panel. This particular type of panel would be used to cover a flank array sonar in a ship or submarine. The case considered is that of a panel with all of its edges mechanically clamped and subject to pressure loading on its convex surface. A comprehensive program of testing, to determine the orthotropic elastic properties of the laminated composite panel material is described, together with a series of pressure tests on 1:5 scale sonar panels. These pressure tests were carried out in a purpose designed test rig, using air pressure to provide simulated hydrostatic and hydrodynamic loading. Details of all instrumentation used in the experimental work are given in the thesis. The experimental results from the panel testing are compared with predictions of panel behaviour obtained from both the Galerkin solution of Flugge's cylindrical shell equations (orthotropic case), and finite element modelling of the panels using PAFEC. A variety of appropriate panel boundary conditions are considered in each case. A parametric study, intended to be of use as a preliminary design tool, and based on the above Galerkin solution, is also presented. This parametric study considers cases of boundary conditions, material properties, and panel geometry, outside of those investigated in the experimental work Final conclusions are drawn and recommendations made regarding possible improvements to the procedures for design, manufacture and fixing of sonar panels in the Royal Navy.
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Afifi, Amal Afifi Mohamed. "Buckling of stiffened pultruded GRP plates and columns." Thesis, Lancaster University, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.497222.
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The research work presented in this thesis is focused or investigating the buckling behaviour of wide range pultruded structural GRP profiles. Investigations of both global and local buckling of GRP profiles have been carried out to determine the buckling capacities. An investigation on improving the buckling capacity of plates and columns was carried out. The program of research undertaken to enhance column buckling capacity included analytical and finite element modelling of the buckling of GRP plates and columns and experimental work on the buckling of GRP columns.
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Velecela, Chuquilla Orlando Jonathan. "Energy absorption capability of GRP composite sandwich structures." Thesis, University of Sheffield, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.434504.
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Charlesworth, Amanda. "Signalling pathways mediated by the bombesin/GRP receptor." Thesis, University College London (University of London), 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.244267.
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Engstrand, Andreas. "Railway surveying - A case study of the GRP 5000." Thesis, KTH, Geoinformatik och Geodesi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-31747.
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The GRP 5000 is a track measuring trolley capable of collecting track geometry data and performing clearance analyses based on laser scanning technology. The obtained laser data can also be used for as-built documentation, and the track recording functionality makes applications such as surveying, tamping assistance and slab track construction possible. The accuracy, huge data amount and time efficiency by which the system operates sets a new standard in railway surveying, and outdates traditional methods of manual and visual inspection. This thesis is a case study of the GRP 5000 with several objectives: a functional and technical description of the system is given; the accuracy of the system is evaluated, showing overall good values except for one of the sensors used; comparisons are made to other railway surveying techniques, such as track recording vehicles, manual devices and other track recording trolleys; possible improvements are pointed out, both based on comparison results as well as testing results. Finally, new and innovative ways of using the trolley, such as offtrack usage, as well as for the obtained laser data, such as GIS, maintenance aspects and CFD aspects, are examined.
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Wang, Pu. "Structural integrity of bolted joints for pultruded GRP profiles." Thesis, Lancaster University, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.429955.
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Pultruded glass-fibre reinforced plastics (GRP) are becoming a popular alternative to conventional materials in Civil Engineering industry. The work presented in this thesis attempts to carry out an integrated and comprehensive programme of research on pultruded GRP bolted joints, in order to provide useful data, knowledge and guidance for design engineers seeking to use bolted joints in pultruded GRP structures. The research was sub-divided into three phases. Phase 1 included determining material properties, conducting tests in double-lap single-bolt tension joints at elevated temperature and starting to develop ANSYS FE models of single-bolt joints. Phase 2 covered testing of double-lap single-bolt tension joints under wet and hot-wet conditions, FE stress and displacement analyses of the tested joint geometries and assessing existing joint design approaches. In Phase 3 the focus was on testing concentrically loaded double-lap multi-bolt tension joints and FE modelling of these joints. In addition, work was undertaken on correlating strains around the hole edge, recorded using the PhotoStress method and conventional strain gauges, with FE analysis. Work was also undertaken on an assessment of current approaches to the design of bolted joints in fibre-reinforced polymeric composite materials, particularly the EUROCOMP Simplified and Hart-Smith design methods.
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Furniss, Jonathan P. "Testing and evaluation of GRP rockbolts for tunnel reinforcement." Thesis, University of Nottingham, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.395497.
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Price, J. N. "The propagation of stress corrosion cracks in aligned GRP." Thesis, University of Liverpool, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.372730.
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Eksik, Ömer. "Structural performance of GRP top hat stiffened marine structures." Thesis, University of Southampton, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.431952.
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Chen, Fangping. "Study of blister formation in GRP laminates in water." Thesis, Loughborough University, 1989. https://dspace.lboro.ac.uk/2134/33055.
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Glass fibre reinforced polyesters (GRP) are widely used in boat and swimming pool manufacture. One drawback for these materials is that they may develop blistering after prolonged and continuous contact with water. The aim of the research programme reported in this thesis is to understand the fundamental reasons for the blister formation, as well as the factors affecting it. Various polyester resins, epoxy resin, vinyl ester resin, different chopped strand glass mats (CSM) and initiators were used for GRP laminates and blister trials carried out. Blisters were examined visually and by an optical microscope; they are classified into four groups according to their origins: (1) contaminants, (2) bubbles, (3) pre-cracks, (4) glass fibre bundles. Detailed study of their relative importance shows that the last two categories are most significant.
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Lutz, Cyprien. "Structural integrity of bolted joints for pultruded GRP profiles." Thesis, University of Warwick, 2004. http://wrap.warwick.ac.uk/110311/.
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Presented in this thesis is a combined physical testing and computational modelling programme of research for the structural integrity of bolted joints for Pultruded Fibre Reinforced Polymer (PFRP) profiles. The work was carried out in a joint EPSRC funded Structural Integrity (SI) project between the Universities of Warwick and Lancaster. It will be shown in the thesis that it provides a significant new body of scientific understanding and relevant independent joint test data, which can be used in the future preparation of design guidance for the safe and rational design of joints. The contribution from the author to this SI project on plate-to-plate steel bolted joints can subdivided into four parts. The first part includes the evaluation of the 10 single-bolted and the 5 multi-bolted double lap-joint test series that appeared before 2001. This identifies that the 15 test series, from 10 centres, are often different because the researchers chose different parameters to study. Of the 800 concentric strength tests 640 were single-bolted and 160 were multi-bolted. It is noteworthy that few of these previous tests include environmental conditioning of the joints. A review of design methods is given in this part of the thesis. This shows that significant joint test data is required to appraise SI design methods for PFRP bolted joints, such as presented in the EUROCOMP Design Code and Handbook of 1996 and in 1981 by Hart-Smith. The EUROCOMP simplified and rigorous methods are expected to be generic and involve damage tolerance to increase the strength of the joint design. It is further found that application of these methods requires Finite Element (FE) stress calculations for the target analysis due to bolt bearing, and for the source analysis, for multi-bolted joints, to determine the bolt load distribution and by-pass loads. Parts two and three of the contribution from the author are combinations of experimental and FE analysis work that focuses on the target and the source problems, respectively. The strain field close to a notch is measured in part two using a pin-bearing test method and strain gauged specimens. To find out if FEA can predict the target strains/stresses an ABAQUS© FE model is developed. The PFRP material is assumed to be homogeneous and possess orthotropic properties. It is shown that a linear elastic analysis, with contact and friction modelled, gives strains that are similar to those measured. This observation is supported by a small photo-elastic strain analysis using the GFP 1000 system from Stress Photonics. By way of the evaluation of previous testing in part one it was decided in part three to conduct a comprehensive series of multi-bolted joint tests. Constant variables in this series of concentric loaded tests are the PFRP material, the plate thickness, the material orientation, the bolt diameter, the clearance hole size, and the bolt torque. This test series, design using a method by Taguchi, comprised four different joint configurations, twelve different joint geometries and four different environmental conditionings (including a temperature of 60oC and ‘wet’ ageing for 1000hrs). The author presents the testing procedure and 432 resistance results for 144 different joints, having a batch size of three. Mechanisms and modes of failure are identified, and several unrelated to the distinct modes of bearing, shear-out and net-tension used in current design approaches are presented. Using this fairly large number of consistent data points an evaluation is made on the influence of the various variables. It is shown that is not straightforward to establish simple strength trends. Furthermore, the findings of this test series suggest that a batch size of three is too small, as batch strength variability is relatively high. By way of a Round-Robin exercise between the two Universities, with joints having a batch size of 10, it is shown that the high strength variability can be associated with the non-homogeneity of the reinforcement arrangement in the PFRP material. Two multi-bolted joints having three rows of three bolts are instrumented with strain gauges to determine the strain distributions linked to bolt load distribution and by-pass loads. Measured strains are compared to numerical predictions from an ABAQUS FE analysis using the same modelling methodology as for the pin-bearing target analysis. The source analysis comparison is acceptable, but like many of the results presented in the thesis it appears likely that the experimental measurements are affected by the non-homogeneity in the macrostructure of the PFRP. Presented in part four is a preliminary appraisal of the EUROCOMP simplified design method and the Hart-Smith design method. The EUROCOMP method is shown to possess deficiencies, via a critique by Lancaster University, which indicates that it cannot be used in practice. By taking information from the multi-bolted joint test series in part three the author constructs semi-universal design charts using the Hart-Smith method, which can be used to design joints with changing geometry. An important finding from this preliminary appraisal is that the SI design methods are difficult to apply since they require lots of physical test data and relevant and reliable stress results from FEA. Finally, despite the programme of research providing a significant new body of scientific understanding and relevant independent joint test data it is concluded that further work is needed before an SI method for the universal design of plate-to-plate PFRP bolted joints can be considered for a code of practice.
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Gray, Joseph. "The design, synthesis and biochemical application of bombesin/grp analogues." Thesis, Queen's University Belfast, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317440.
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Al-Rawe, Auday. "Design methodology for optimising the performance of underground GRP tanks." Thesis, Nottingham Trent University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263388.
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Cornélio, Daniela Baumann. "Neuropeptídeos GRP e BDNF como alvos moleculares em neoplasias femininas." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2012. http://hdl.handle.net/10183/72309.
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Receptores de neuropeptídeos e neurotrofinas constituem importantes alvos moleculares no câncer. Fatores de crescimento como o peptídeo liberador da gastrina (GRP) e fator neurotrófico derivado do cérebro (BDNF) estão envolvidos na proliferação celular e progressão do câncer, influenciando na invasão local, angiogênese, metastatização e apoptose. O receptor de GRP (GRPR) tem sido identificado em muitos tumores humanos, mas até o presente trabalho não havia nenhuma informação na literatura quanto à sua expressão em câncer cervical. Nosso estudo inicial demonstrou pela primeira vez a expressão aberrante em GRPR em displasias e câncer do colo uterino, levantando a hipótese de que este receptor poderia estar implicado no processo carcinogênico destes tumores. Para explorar o papel de GRPR como um biomarcador de lesões de colo uterino, em nosso segundo estudo objetivamos avaliar o potencial diagnóstico da detecção de GRPR por imunocitoquímica, técnica que também não havia sido previamente descrita. Verificamos que este receptor foi fortemente associado com displasia e neoplasia cervical invasora. Além disso, o exame demonstrou elevada acurácia para lesões classificadas como células escamosas atípicas de significado indeterminado (ASCUS). Com base nestes resultados, concluímos que a expressão de GRPR por imunocitoquímica pode ser considerada como um método adicional para a detecção de lesões cervicais. Estudos prévios indicam que o bloqueio de GRPR ou do receptor tropomiosina quinase B (TrkB) pode ter efeito antiproliferativo em células de câncer. Neste trabalho mostramos que a ativação do GRPR pode reduzir, ao passo que o bloqueio pode aumentar a viabilidade de células de câncer de ovário, mama e colo uterino. Além disso, demonstramos que a inibição TrkB reduz a viabilidade destas células, sendo que o tratamento com BDNF aumentou a viabilidade de células de ovário. Os resultados obtidos reforçam o conhecimento de que as sinalizações GRP/GRPR e BDNF/TrkB regulam a viabilidade de células de câncer. Ainda mais importante, fornecem a primeira evidência de que, sob certas condições, a ativação de GRPR pode inibir, em vez de estimular, células neoplásicas de mama, ovário e colo uterino.Neuropeptide and neurotrophin receptors are increasingly important molecular targets in cancer. Growth factors as the gastrin-releasing peptide (GRP) and brain-derived neurotrophic factor (BDNF) are involved in cell proliferation and cancer progression, enhancing local invasion, angiogenesis, distant metastasis and apoptosis. The GRP receptor has been identified in many human malignancies, but no information regarding its expression in cervical cancer was found in the literature. Considering that cervical cancer is a very important cause of morbidity and mortality worldwide, we aimed to evaluate the GRPR expression profile in preinvasive and invasive cervical lesions. Our initial study demonstrated for the first time the aberrant GRPR expression in human cervical dysplasia and cancer, raising the hypothesis that GRPR could be implicated in the carcinogenic process of cervical tumors. To further exploit GRPR as a biomarker, in our second study we aimed to evaluate the diagnostic potential of GRPR immunocytochemistry in detecting cervical dysplasia and invasive cancer. This was the first immunocytochemical evaluation of GRPR expression in cervical epithelial cells. This receptor was strongly associated with cervical dysplasia and invasive cancers. Additionally, GRPR immunosignaling showed high accuracy in detecting dysplasias in cells classified as atypical squamous cells of undetermined significance (ASCUS). Based on these results, we concluded that immunocytochemistry for GRPR may be regarded as a valuable method for early detection of cervical intraepithelial neoplasia. Previous studies have indicated that compounds that act by blocking gastrin-releasing peptide receptors (GRPR) or tropomyosin receptor kinase B (TrkB) receptors can display antiproliferative activities against cancer cells. Here we show that GRPR activation can reduce, whereas its blockade can increase, the viability of breast, ovarian, and cervical cancer cell lines. In addition, we demonstrate that TrkB inhibition reduces the viability of these cells and BDNF increases the viability of ovarian cells. The results support the view that GRPR and BDNF/TrkB signaling regulate cancer cell viability. Most importantly, the findings provide the first evidence that, under certain conditions, GRPR activation can inhibit, rather than stimulate, breast, ovarian and cervical cancer cells.
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Wahono, A. R. "Response of GRP sandwich panels to quasi-static and blast pressure." Thesis, University of Manchester, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.488320.
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Barber, Simon. "Industrial mediation in jazz production : A case study of GRP records." Thesis, University of Liverpool, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.511095.
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Varnam, Steven Michael. "Local loads on attachments and nozzles to GRP cylinders of varying thickness." Thesis, University of Manchester, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320762.
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Frånlund, Ebba. "Exon sequencing of the gene encoding UCMA/GRP in healthy and clinical subjects." Thesis, Linköpings universitet, Institutionen för fysik, kemi och biologi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-68647.
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Mineralization of soft tissues can cause significantly increased morbidity and mortality. The mechanism for this process is still unknown; however, patients with chronic kidney disease (CKD) are at high risk of developing vascular calcifications. Coronary artery calcification occurs faster in CKD patients undergoing dialysis in comparison with the general population. The pathological process of vascular calcification is the leading cause of death in patients with CKD. Upper zone of growth plate and cartilage matrix associated protein (UCMA) is a novel vitamin-K dependent (VKD) protein expressed in bone and the vascular system. The UCMA protein contains 15 γ-carboxyglutamic acid (Gla) residues in its 138 residue sequence which is the highest ratio between the number of Gla-residues and the size of the mature protein found in any protein so far. These Gla-residues form a domain that gives unique calcium binding properties for UCMA with high affinity for calcium phosphate crystals (i.e., hydroxyapatite). Even though the function of UCMA remains to be elucidated, it has been speculated that UCMA inhibits calcification of soft tissues and could therefore have a protective function against vascular calcification. Any mutations in the gene coding for UCMA might lead to a diminished function or defective protein. The aim of this study was to determine whether the gene encoding UCMA in patients with the most progressed stage of CKD (stage 5 CKD) contained any mutations. This was accomplished by performing a full re-sequencing of all five exons with dideoxy sequencing in 16 patients with stage 5 CKD on heamodialysis. If any mutations were discovered, pyrosequencing would be performed on 98 healthy control individuals. This would help to determine if the mutation was exclusive for the patients or existed in the general population as well. Genomic DNA was extracted from whole blood originating from 16 patients with CKD on haemodialysis. Each of UCMAs five exons were amplified with PCR and the results were visualized using gel electrophoresis. Each exon was re-sequenced and pyrosequencing was performed on 98 healthy control samples. The acquired results were compared with the sequence of the UCMA gene identified at NCBI-GenBank (NCBI, build 37.2, NM_145314.1, Gene ID: 221044) and the Ensemble genome browser (ENSG00000165623). In addition, the frequencies of each SNP were calculated and compared with a study at the Ensemble database originating from the 1000 genomes project (1000GENOMES:low_coverage: CEU). Because the population of our study group was too small to yield appropriate power for statistical calculations, no definite conclusions could be drawn from the acquired results. Nevertheless, this is the first patient group with CKD ever studied and should thus be regarded as a pilot study due to the limited size. However, no indication was found that UCMA had major defects in the investigated patients. Instead, a heterozygous transversion mutation was found in SNP rs4750328, indicating that the site of this SNP is subject to other modifications. Furthermore, a novel SNP was discovered which has not been described in other populations to our knowledge. The novel SNP is non-synonymous (i.e., causes an amino acid exchange) and located at the carboxyl-terminal of the protein. A serine is incorporated instead of threonine giving a 138Thr>Ser change since the last ACC codon in exon 5 (adjacent to the stop codon) is altered to an AGC codon. The UCMA 138Thr>Ser polymorphism was submitted to the dbSNP database and has been assigned the accession number ss283927876, which will be publicly available upon the release of the next dbSNP Build, B134. In order to determine the physiological significance of the discovered SNP, functional studies are required on both the wild-type and mutated UCMA variants.
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Javed, Muhammad Afzal. "Stability analysis of P.F.R.P. box-sections." Thesis, University of Newcastle upon Tyne, 2003. http://hdl.handle.net/10443/3623.
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lass fibre reinforced plastic (GRP) structural profiles, in standard shapes and sizes are now being commercially manufactured by the process of pultrusion. GRP profiles are light weight, posses higher specific strengths and are more durable than the conventional metal or concrete counterparts. GRP pultruded profiles have open or closed cross-sections comprising thin composite walls of low elastic moduli. Stability failure has been identified as the main cause of failure for these profiles when subjected to compressive stresses, as it may occurs at stresses much lower than the ultimate strengths. Therefore, the load carrying capacities of composite compression members mainly depends upon stability criteria. The conventional stability analyses for the prediction of buckling loads are not considered adequate as the GRP material is orthotropic and its behaviour is different from steel (non-yielding). The existing guidance for the design of composite members under compression ignores the presence of geometrical imperfections inherited in the pultruded profiles, whilst, experimental evidence suggests considerable loss of stiffness due to the imperfections particularly in the intermediate column heights. The design guidance provided by the manufacturers gives empirical equations based on data obtained from experiments on specified profiles. A universal design curve based on the experimental results of concentrically loaded GRP columns has been developed and presented. However, conducting a vast experimental study is not always feasible. The need to develop a procedure, predicting failure load numerically for the development of a design curve for GRP columns has been recognised. Two GRP box-sections (closed square cross-sections) have been investigated for failure/buckling loads using experimental and numerical methods. In the experimental phase, specimen columns of various heights have been concentrically loaded in compression to measure the failure loads. Experimental results have been compared with the theoretical predictions made using classical methods and the equations given by the design manuals. Based on the experimental and analytical failure loads, an experimental design curve has been derived. In the numerical study, 3-dimensional full scale finite element models representing experimental configuration of the composite columns, have been analysed using both linear and nonlinear solutions. Imperfections of known amplitudes have been included parametrically to establish the sensitivity of the failure loads towards imperfections. Imperfect model have been calibrated for the estimation of imperfection amplitude present in the profiles using experimental data. Using the numerical and analytical data, a design curve has been derived establishing interaction coefficients for each profile. The numerical design curve is compared with the experimental design curve for the validation of the numerical procedure adopted in this study. Effects of perforations (circular holes) on the buckling stiffness of GRP box-section columns have also been investigated. Holes are drilled in the walls of profiles and tested experimentally to measure the loss in the buckling loads. Finite element models of columns with holes have been developed and analysed for buckling loads. Comparisons of experimental and numerical results are plotted. For use in the numerical representation of the composite columns, mechanical properties of the orthotropic GRP material of the both sections have been established analytically and experimentally. In-plane shear properties have been measured by physically testing standard sized coupons, extracted along the length of profiles. However, short coupons were available in the transverse directions due to dimensional constraints. Short coupons, similar in geometry to the standard coupon, but smaller in size, have been validated for performance using finite element analyses and comparing the outcomes with the models of standard coupons. Both standard and short coupons have been used for the experimental measurement of the in-plane shear properties. Compression properties have also been measured experimentally. Ultimate failure/buckling loads of the composite columns depend upon their heights, material properties, and the cross-sectional dimensions. These factors have been combined into one characteristic parameter 'λ', the slenderness ratio. As the later two factors are constant for a particular box-section profile, the ultimate loads depend upon column heights. Four types of failure modes; global, local, modal interaction and material failure have been observed. The loss in the buckling stiffness is minimal for smaller circular holes, provided the interval between holes is not less than 20 times the diameter of the holes. For bigger holes and an inter hole spacing of 10time the diameter, a loss of 30% have been measured. Finite element representation of pultruded columns adequately predicted the numerical failure loads and failure modes for most of the column heights.
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Zhang, Xiangping. "Characterization of filament wound GRP pipes under lateral quasi-static and low velocity impact loads." Thesis, University of Aberdeen, 1998. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU551705.
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Glass-fibre reinforced plastic pipes are widely used to convey fluids for various purposes. They offer a number of distinct advantages over conventional metals, such as high specific strengths, high specific moduli, superior corrosion resistance and low coefficient of thermal expansion. However, their behaviour under lateral quasi-static and impact loading are still not well known. The research programme described in this thesis was designed to characterise the performance of 55° winding angle GRP pipes, subjected to lateral quasi-static and impact loading. Two approaches: experimental tests and finite element analysis, were used to investigate the behaviour of the GRP pipes. The experimental investigation was started with diametral compression of short GRP pipes to examine the structural behaviour and failure mechanisms. Subsequently, lateral indentation tests were conducted on rigid-foundation supported or simply supported specimens using two different indenter geometries: line-ended and flat-ended. Furthermore, low-velocity impact tests were performed under similar conditions as those for indentation tests in order to characterise the response of the GRP pipes and to identify the correlation between the two forms of loading. The pipes exhibited multi-mode failure mechanisms, resin cracks, delaminations and fibre breakage. It is found that delamination, which resulted in significant loss in stiffness and strength, was the most significant mode of failure for the GRP pipes. A good correlation in behaviour was identified between quasi-static indentation and its energy equivalent low-velocity impact when the global bending stiffness of the GRP specimens were high. Specimens with span S 10.5D i, where Di is the internal diameter of the pipe, are considered to have high bending stiffness, while simply supported specimens with S10.5D i have low bending stiffness. Irrespective of the support conditions and loading type, specimens with high bending stiffness followed a failure mechanism sequence: local resin failure, delamination and the fibre breakage. However, the large global bending experienced by low bending stiffness specimens resulted in a change of failure mechanism, only local damage and surface tensile cracks were observed.
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Abd, El-Galiel Wael Refat. "Studies on radiometal chelator-bombesin peptide-based radiopharmaceuticals for tumor GRP-receptor substype mediated radioimaging." Diss., Columbia, Mo. : University of Missouri-Columbia, 2007. http://hdl.handle.net/10355/5962.
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Thesis (Ph.D.)--University of Missouri-Columbia, 2007.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on March 12, 2009) Includes bibliographical references.
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Carturan, Federico. "Seismic Risk Analysis of Revenue Losses, Gross Regional Product and transportation systems." Doctoral thesis, Università degli studi di Padova, 2013. http://hdl.handle.net/11577/3423071.
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Natural threats like earthquakes, hurricanes or tsunamis have shown seri- ous impacts on communities. In the past, major earthquakes in the United States like Loma Prieta 1989, Northridge 1994, or recent events in Italy like L’Aquila 2009 or Emilia 2012 earthquake emphasized the importance of pre- paredness and awareness to reduce social impacts. Earthquakes impacted businesses and dramatically reduced the gross regional product. Seismic Hazard is traditionally assessed using Probabilistic Seismic Hazard Anal- ysis (PSHA). PSHA well represents the hazard at a specific location, but it’s unsatisfactory for spatially distributed systems. Scenario earthquakes overcome the problem representing the actual distribution of shaking over a spatially distributed system. The performance of distributed productive systems during the recovery process needs to be explored.
Scenario earthquakes have been used to assess the risk in bridge networks and the social losses in terms of gross regional product reduction. The proposed method for scenario earthquakes has been applied to a real case study: Treviso, a city in the North East of Italy. The proposed method for scenario earthquakes requires three models: one representation of the sources (Italian Seismogenic Zonation 9), one attenuation relationship (Sa- betta and Pugliese 1996) and a model of the occurrence rate of magnitudes (Gutenberg Richter). A methodology has been proposed to reduce thou- sands of scenarios to a subset consistent with the hazard at each location. Earthquake scenarios, along with Mote Carlo method, have been used to simulate business damage. The response of business facilities to earthquake has been obtained from fragility curves for precast industrial building. Fur- thermore, from business damage the reduction of productivity has been simulated using economic data from the National statistical service and a proposed piecewise “loss of functionality model”. To simulate the economic process in the time domain, an innovative businesses recovery function has been proposed.
The proposed method has been applied to generate scenarios earthquakes at the location of bridges and business areas. The proposed selection method- ology has been applied to reduce 8000 scenarios to a subset of 60. Subse- quently, these scenario earthquakes have been used to calculate three system performance parameters: the risk in transportation networks, the risk in terms of business damage and the losses of gross regional product. A novel model for business recovery process has been tested. The proposed model has been used to represent the business recovery process and simulate the effects of government aids allocated for reconstruction.
The proposed method has efficiently modeled the seismic hazard using scenario earthquakes. The scenario earthquakes presented have been used to assess possible consequences of earthquakes in seismic prone zones and to increase the preparedness. Scenario earthquakes have been used to sim- ulate the effects to economy of the impacted area; a significant Gross Regional Product reduction has been shown, up to 77% with an earthquake with 0.0003 probability of occurrence. The results showed that limited funds available after the disaster can be distributed in a more efficient way.Gli eventi naturali quali terremoti, uragani, tsunami causano importanti impatti negativi nelle comunità. Gli eventi accaduti in passato, come il terremoto di Loma Prieta del 1989 o i più recenti eventi sismici come L’Aquila 2009 o Emilia Romagna 2012, hanno evidenziato la necessità e l’importanza di un’attiva preparazione pre-evento e la consapevolezza che sia necessario ridurre le conseguenze negative indotte da tali eventi. In tale ambito si inserisce l’attività di ricerca, focalizzandosi in particolar modo sulle conseguenze che eventi sismici hanno nel prodotto interno lordo della regione colpita. Nella letteratura scientifica non sono stati definiti scenari di scuotimento sismico ad uso ingegneristico in Italia. Il dipartimento di Protezione Civile ha pubblicato le mappe di pericolosità sismica, che sono state ricavate con analisi Probabilistic Seismic Hazard Analsys, tuttavia tali mappe non permettono la puntuale valutazione dei singoli scenari sismici che contribuiscono alla pericolosità. Risulta interessante, inoltre, determinare quali siano le conseguenze degli eventi sismici nei sistemi produttivi e quale sia il loro impatto nella riduzione del prodotto interno lordo. Infine, la riduzione di produttività nel sistema delle attività risulta legata alla presenza di un efficiente sistema dei trasporti. Il sistema dei trasporti viene danneggiato dall’evento sismico, pertanto è necessario determinare la relazione esistente tra questo ed il sistema produttivo. Inoltre, per effettuare analisi economiche di tipo Benefici-Costi è necessario sviluppare modelli di recupero e simulare gli effetti di aiuti statali nel processo di ricostruzione. Lo scopo della ricerca è stato pertanto la costruzione di scenari sismici utilizzando un approccio ingegneristico, tali scenari sono stati poi utilizzati per valutare le conseguenze economiche nelle regioni colpite da terremoto e l’interazione tra il sistema dei trasporti e quello produttivo. Per promuovere la consapevolezza degli effetti prodotti da un terremoto in una comunità intesa come un insieme unitario, è stata proposta una metodologia per lo sviluppo di scenari sismici. Tali scenari sono stati impiegati per valutare i danni agli edifici produttivi e ai ponti presenti nella rete di trasporto. La metodologia così sviluppata è stata applicata ad una regione test, l’area della città di Treviso nel Nord-Est d’Italia. Partendo dalle sorgenti sismogenetiche descritte nel progetto Zone Sismiche 9, impiegando la relazione di attenuazione di Sabetta e Pugliese del 1996 assieme al modello di occorrenza Gutenberg Ricther sono stati generati 8000 scenari sismici. Tale numero è stato ridotto tramite una procedura proposta per la rappresentazione della curva di pericolosità in corrispondenza di ogni singola posizione. Utilizzando il metodo di Montecarlo per il campionamento statistico della fragilità di edifici e di ponti sono state generati gli scenari di danno sismico ai sistemi produttivi ed alle infrastrutture di trasporto. Il rischio indotto dagli eventi sismici è stato poi calcolato e rappresentato tramite la curva di rischio del sistema. Nel corso del lavoro di ricerca sono stati proposti modelli innovativi per quanto riguarda il comportamento delle attività produttive successivamente ai danni causati da terremoti, un modello innovativo per descrivere il processo di ricostruzione degli edifici e quindi il recupero della produttività. Un ulteriore prodotto innovativo è la relazione tra il sistema produttivo e le infrastrutture di trasporto. I risultati ottenuti possono così essere riassunti: una procedura innovativa per la generazione di scenari sismici partendo dalla descrizione delle zone ad attività sismica, di utilizzo ingegneristico. Tale procedura può essere generalizzata per l’applicazione ad altre realtà. Un insieme di scenari di scuotimento sismico compatibili con la descrizione della pericolosità di sito è stata presentata per la prima volta Italia. Un modello innovativo per la valutazione della funzionalità post-evento in relazione alla fragilità degli edifici è stato proposto. Un innovativo modello per rappresentare il processo di ricostruzione post-terremoto è stato presentato per la prima volta. Sono stati esplorati gli effetti degli aiuti finanziari erogati dalle istituzioni. E’ stata valutata la relazione tra il sistema produttivo ed il sistema di trasporto.
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Francl, Jessica M. "Regulation of neuropeptide release in the SCN circadian clock: in vivo assessments of NPY, VIP, and GRP." Kent State University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=kent1289328898.
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Heierli, Daniel. "Gefässspezifische Expression des Bohnengens grp 1.8 : modularer Aufbau des Promotors und Charakterisierung des bZIP-Proteins VSF-1 /." [S.l.] : [s.n.], 1993. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=10337.
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Ziv, Michael. "A study of the behavior of the GRP hat-stiffened panel bondline under high strain rate loading." Thesis, Monterey, California. Naval Postgraduate School, 1995. http://hdl.handle.net/10945/26270.
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Shah, Syed Iftikhar Hussain, and Syed Hassan Shaheed. "PERFORMANCE EVALUATION OF MANET ROUTING PROTOCOLS." Thesis, Blekinge Tekniska Högskola, Sektionen för datavetenskap och kommunikation, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-1101.
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The research study determines OPNET simulation to evaluate the MANET routing protocols i.e. AODV, DSR, GRP and OLSR performance for HTTP and FTP base application traffic. Results from the simulation result helps to measure the performance matrix i.e. packet delivery fraction, normalized routing load, throughput and end to end delay. Scalar values are extracted from simulation to plot desired performance graphs to analyze. The research results and conclusion produces enough information for the selection of best routing protocol for MANET in terms of HTTP and FTP application types.
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Czepielewski, Rafael Sanguinetti. "Investiga??o dos efeitos do pept?deo liberador de gastrina (GRP) e seu antagonista RC-3095 em c?lulas mieloides." Pontif?cia Universidade Cat?lica do Rio Grande do Sul, 2016. http://tede2.pucrs.br/tede2/handle/tede/7588.
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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES
Tumor microenvironment and inflammatory diseases promote alterations in our immune system along with their development. Several molecules are implicated in this modulation and are therefore considered therapeutic targets. Gastrin-releasing peptide (GRP) is produced in tumors where it promotes cellular proliferation. It is also correlated with chronic diseases, as in rheumatoid arthritis and asthma, and in the acute condition of sepsis. Recently, our group found a direct GRP action over neutrophils, promoting migration. This work aimed to study the interface between GRP-producing tumors and the recruitment of immune cells, as well as extend the cellular studies about neutrophil activation and migration processes promoted by the peptide. In tumors, we observed that a lung adenocarcinoma cell line does not proliferate in response to GRP. Yet, it is induced to migrate when exposed to the peptide, indicating a potential role for GRP in metastasis of this type of cancer. In our tumor immunology studies, we established a novel in vivo model by overexpressing GRP in a melanoma cell line (B16F10). We observed the augment of infiltrating inflammatory monocytes in the tumor microenvironment of these tumors. In parallel, we verified that reactive oxygen species production and migration in response to GRP is dependent of the NADPH oxidase complex. GRP stimulation promotes an intense activation, which culminates in neutrophil extracellular traps (NETs) release. In addition, the GRP receptor (GRPR) antagonist RC-3095 presented anti-inflammatory potential, inhibiting neutrophil migration towards IL-8 and reducing the extent of acetaminophen-induced liver damage. This effect was due to motility alterations in infiltrating neutrophils within the tissue and reduction of cell adhesion molecules. The results presented herein demonstrate the wide panorama of GRP?s interactions in tumor and immune biology.
O microambiente tumoral e as doen?as inflamat?rias promovem altera??es nas c?lulas do nosso sistema imune ? medida que progridem. Diversas mol?culas est?o envolvidas nessa modula??o, e por isso s?o alvos terap?uticos. O pept?deo liberador de gastrina (GRP) ? produzido por tumores, onde promove prolifera??o celular. Este tamb?m est? correlacionado com doen?as cr?nicas como a artrite reumatoide e asma, e em doen?as agudas, como a sepse. Recentemente, nosso grupo descobriu a??o direta do GRP em neutr?filos, promovendo indu??o de migra??o. O presente trabalho se prop?s a estudar a interface entre tumores produtores de GRP e o recrutamento celular, assim como aprofundar os estudos celulares sobre os processos de ativa??o e migra??o de neutr?filos promovidos pelo pept?deo. Em tumores, observamos que uma linhagem de adenocarcinoma pulmonar n?o prolifera quando exposto ao GRP, por?m ? induzida a migrar quando exposta ao pept?deo, estabelecendo um potencial papel deste na promo??o de met?stases para esse tipo tumoral. Na interface da imunologia tumoral, atrav?s do desenvolvimento de um modelo in vivo de superexpress?o de GRP em melanoma murino (B16F10), observamos que esse aumento do GRP induz a infiltra??o de mon?citos inflamat?rios no microambiente tumoral. Em paralelo, verificamos que a produ??o de esp?cies reativas de oxig?nio e a migra??o em dire??o ao GRP s?o dependentes do complexo NADPH oxidase. Esse est?mulo promove ativa??o intensa, culminando na produ??o de redes extracelulares de neutr?filos (NETs). J? o antagonista do seu receptor, GRPR, apresentou potencial antiinflamat?rio, sendo capaz de inibir a migra??o neutrof?lica via modula??o de IL-8 e reduzindo a extens?o da les?o hep?tica induzida por paracetamol (acetaminofeno), alterando a motilidade dos neutr?filos no tecido e a express?o de mol?culas de ades?o. Assim, os resultados aqui apresentados demonstram um panorama amplo da fun??o do GRP na biologia tumoral e no sistema imune.
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Hajjaj, Bouchra. "Conception, synthèse et évaluation biologique d’antagonistes de la bombésine pour la visualisation de cancers par imagerie médicale." Thesis, Montpellier 1, 2013. http://www.theses.fr/2013MON13517.
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La surexpression des récepteurs GRP au niveau de différents types de cancers communs offre la possibilité d'utiliser des analogues radiomarqués de la bombésine pour leur diagnostic et leur traitement. Ce travail de thèse est consacré à la conception, la synthèse et l'évaluation biologique de nouveaux radiopharmaceutiques, contenant un antagoniste des récepteurs GRP, un bras espaceur et le chélatant cyclique DOTA. Nous avons tout d'abord déterminé la longueur du bras espaceur permettant une optimisation des propriétés biologiques. Puis en se basant sur les résultats de cette étude nous avons réalisé la synthèse et l'évaluation biologique de radio-ligands constitués d'antagonistes originaux des récepteurs GRP. Ces antagonistes ont été conçus en se basant sur le composé JMV 594, un antagoniste puissant de la bombésine synthétisé dans notre laboratoire. En plus de modifications réalisées sur ce peptide, des dimères ont également été synthétisés de façon à obtenir des antagonistes plus stables et plus affins pour les récepteurs GRPThe abundant expression of the GRP receptor in many frequently occurring cancers that inflict humans provides the opportunity to use radiolabeled bombesin analogs for their diagnosis and treatment. This postgraduate work is dedicated to the design, synthesis and biological evaluation of new radiopharmaceuticals. These are made up of a GRP receptor antagonist, a spacer and the cyclic metal chelating agent DOTA. We first determined the spacer length which has optimal biological properties. Moving forward from this study, different radio-ligands containing new bombesin antagonists have been synthesized and biologically evaluated. Those antagonists are based on compound JMV 594, a powerful bombesin antagonist synthesized in our laboratory. Besides modifications of this peptide also dimers have been made to obtain more stable bombesin antagonist with more affinity to the GRP receptor
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Kleinspehn, Edgar Verfasser], and Eike Sebastian [Akademischer Betreuer] [Debus. "Kombinatorische Anwendung von TRH und GRP in einem humanen in-vitro-Wundheilungsmodell / Edgar Kleinspehn ; Betreuer: E. Sebastian Debus." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2016. http://d-nb.info/1121783074/34.
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Chile, Thais. "Análise da expressão dos genes CRABP1, CRABP2, GRP e RERG em adenomas hipofisários funcionantes e clinicamente não funcionantes." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/5/5135/tde-05032010-171210/.
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Os tumores hipofisários representam cerca de 10% a 15% das neoplasias intracranianas. Embora a etiopatogenia ainda não seja plenamente caracterizada, muitos mecanismos moleculares envolvidos na tumorigênese hipofisária já foram desvendados. Utilizandose da metodologia de arranjos de cDNA contendo aproximadamente 20.000 genes, nosso grupo recentemente comparou a expressão de duas condições distintas: um pool de quatro adenomas hipofisários clinicamente não funcionantes e a metástase de um carcinoma hipofisário não funcionante. Vários genes mostraram-se diferencialmente expressos, entre eles, CRABP1 (cellular retinoic acid binding protein 1), CRABP2 (cellular retinoic acid binding protein 2), GRP (gastrin-releasing peptide) e RERG (RAS-like, estrogen-regulated, growth inhibitor). Este estudo visou avaliar a expressão desses quatro genes em uma série de 59 adenomas hipofisários (30 adenomas clinicamente não funcionantes, 13 somatotrofinomas, 8 corticotrofinomas e 8 prolactinomas), comparando cada grupo tumoral com um conjunto de tecidos hipofisários normais. Enquanto os prolactinomas demonstraram expressão reduzida do RNAm dos genes CRABP1 e CRABP2 quando comparados ao grupo de tecidos normais, os somatotrofinomas apresentaram expressão reduzida apenas do RNAm de CRABP2. Os adenomas clinicamente não funcionantes, por sua vez, demonstraram menor expressão do RNAm de GRP e maior expressão do RNAm de RERG quando comparados ao grupo de hipófises normais. Portanto, observou-se que tanto o gene CRABP1 quanto os genes CRABP2, GRP e RERG apresentaram diferenças na expressão do transcrito entre os grupos de adenomas de hipófise, contudo, seu papel na tumorigênese hipofisária permanece a ser investigado.Pituitary tumors account for approximately 10%-15% of the intracranial neoplasms. Although the pathogenesis is not fully characterized, many molecular mechanisms involved in pituitary tumorigenesis have been unraveled. Using the methodology of cDNA microarray containing approximately 20000 genes, our group recently compared the expression of two distinct conditions: a pool of four clinically nonfunctioning pituitary adenomas and a spinal cord metastasis of a nonfunctioning pituitary carcinoma. Several genes were shown to be differentially expressed, among them, CRABP1 (cellular retinoic acid binding protein 1), CRABP2 (cellular retinoic acid binding protein 2), GRP (gastrin-releasing peptide) and RERG (RAS-like, estrogen-regulated, growth inhibitor). This study aimed to evaluate the expression of these four genes in a series of 59 pituitary adenomas (30 nonfunctioning, 13 GH-secreting, 8 ACTH-secreting and 8 PRL-secreting adenomas), comparing each tumor group with a set of normal pituitary tissues. While PRL-secreting adenomas showed lower expression of CRABP1 and CRABP2 mRNA when compared with normal tissues, GH-secreting adenomas had only lower expression of CRABP2 mRNA. Clinically nonfunctioning adenomas showed lower expression of GRP mRNA and higher expression of RERG mRNA when compared with the normal pituitary glands. Therefore, it was observed that not only the CRABP1 gene but also the CRABP2, GRP and RERG genes showed differences in transcript expression between the groups of pituitary adenomas. However, their role in pituitary tumorigenesis remains to be investigated.
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Jaeger, Natália. "Investigação do efeito proliferativo e migratório do peptídeo liberador de gastrina (GRP) sobre uma linhagem de adenocarcinoma pulmonar." Pontifícia Universidade Católica do Rio Grande do Sul, 2014. http://hdl.handle.net/10923/6965.
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Previous issue date: 2014Lung cancer is the most commonly diagnosed type of cancer and the leading cause of cancer related mortality in the world, causing nearly one million deaths per year. Among all histological types, adenocarcinoma is the most frequent one (75-80%). Gastrin-releasing peptide (GRP) is considered to be a mitogen, capable of inducing cell proliferation, since it is involved in fetal lung development. This neuropeptide had its effect on tumor growth first identified in human cells of small cell lung cancer, acting as an autocrine growth factor for tumor tissues by binding to its receptor GRPR. The receptor has been found in many tumor types such as prostate, breast, stomach, pancreas and colon. Moreover, this peptide acts as a morphogen, in angiogenesis and is related to inflammatory processes and in the regulation of cells of the immune system. Furthermore, asymptomatic smokers have high levels of GRP in bronchoalveolar lavage and urine. However, little is known about its effects in tumorigenesis and metastasis, and which molecular mechanisms and signaling pathways are responsible for the effects found. Our group demonstrated recently that GRP could act as a chemotactic molecule for neutrophils. Thus, we hypothesized that GRP could be also a chemotactic stimulus to tumor cells expressing the GRPR. In this study, we tested this hypothesis by examining the effect of GRP on proliferation, survival and migration of cells from the adenocarcinoma cell line A549, seeking to identify the mechanisms of action of this peptide. These cells express high levels of GRPR and treatment with GRP leads to activation of kinases such as AKT and ERK1/2 that are involved in the cellular processes mentioned. Our results suggest that GRP is a migratory stimulus to these cells without evidence of significant effect on their proliferation or survival to treatment with the chemotherapy drug cisplatin (CDDP). Nonetheless, they become more sensitive to CDDP when the drug is combined with a GRPR antagonist. Thus, we believe that future studies should consider a possible role for GRP in metastasis of NSCLC.
O câncer de pulmão é o tipo de câncer que mais comumente diagnosticado e o que mais mata no mundo levando a quase 1 milhão de mortes por ano. Entre todos os tipos histológicos, o adenocarcinoma é o mais frequente (75-80%). O peptídeo liberador de gastrina (GRP) é considerado um agente mitogênico, capaz de induzir a proliferação celular, uma vez que está envolvido no desenvolvimento fetal dos pulmões. Este peptídeo teve sua ação sobre o crescimento tumoral primeiramente identificada em células humanas de câncer de pulmão de pequenas células, atuando como fator autócrino de crescimento de tecidos e tumores através da ligação ao seu receptor GRPR. Este receptor foi encontrado em diversos tipos de tumores como próstata, mama, estômago, pâncreas e cólon. Além disso, este peptídeo atua como um morfógeno, na angiogênese e, está relacionado a processos inflamatórios e na regulação de células do sistema imune. E, fumantes assintomáticos possuem altos níveis de GRP no lavado broncoalveolar e na urina. No entanto, pouco se conhece sobre os seus efeitos na tumorigênese e metástase e, quais os mecanismos moleculares e as vias de sinalização que são responsáveis pelos efeitos encontrados. Nosso grupo demonstrou, recentemente, que o GRP pode atuar como uma molécula quimiotática para neutrófilos. Desta forma, hipotetizamos que o GRP poderia constituir num estimulo quimiotático também para as células tumorais que expressão o GRPR. Neste trabalho, testamos essa hipótese, analisando o efeito do GRP sobre a proliferação, sobrevivência e migração de células da linhagem de adenocarcinoma A549, buscando identificar mecanismos de ação desse peptídeo. Esta linhagem expressa altos níveis de GRPR.O tratamento com GRP leva a ativação de quinases como a AKT e ERK1/2 que estão envolvidas nestes processos celulares. Nossos resultados sugerem que o GRP é principalmente um estímulo migratório para estas células, sem evidências de efeito significativo sobre a sua proliferação ou sobrevivência ao tratamento com a droga quimioterápica cisplatina, mas tornam-se mais sensíveis quando a droga é combinada com um antagonista do GRPR. Dessa forma, acreditamos que estudos futuros devam considerar um possível papel para o GRP na metástase.
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Wei, Lixia. "Development of a Novel Protein Based MRI Contrast Agent for Molecular Imaging of Prostate Cancer." Digital Archive @ GSU, 2010. http://digitalarchive.gsu.edu/biology_diss/75.
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Molecular Imaging provides new aspects in cancer diagnosis and treatment. With the ap-plication of imaging and biological techniques, molecular imaging can monitor molecular and cellular changes of different diseases. To interpret the mechanism of disease, more and more at-tention is focused on the development of new probes for molecular imaging. Magnetic resonance imaging (MRI) is a powerful, non-invasive clinical diagnostic tool with high spatial resolution without the limitation of the depth of tissues. Applications of MRI contrast agents can amply the MRI signal during imaging. Many studies have been devoted to developing targeted MR contrast agents. Proteins and peptides have been widely used for target-ing cancer cells in cancer diagnosis and treatments. GRP, gastrin-releasing peptide, is one of a well-characterized group of mammalian bombesin-like peptides. GRP acts through its cell surface receptors, GRP receptor (GRPR). It has been reported that there is a high density of GRP receptors in the majority of prostate carci-noma. In contrast, the GRPRs are not highly expressed in normal cells of most tissues. Thus, this tumor specific expression pattern provides an advantage for cancer targeting. A novel class of MRI contrast agent was designed by adding the Gd3+ binding sites into a stable host protein, the domain 1 of rat CD2. Due to the unique features of the designed metal binding properties, the protein contrast agent (ProCA1) exhibits more than 10-fold enhanced MRI relaxivity compared to that of the more commonly used Gd-DTPA. The high relaxivity of the designed protein contrast agent largely overcomes the major barrier of low sensitivity of MRI techniques. A peptide of ten amino acids from the C-terminal of GRP was grafted onto ProCA1. GRP-grafted protein contrast agents (ProCA1.GRPs) showed the targeting capability to the GRPRs which are over-expressed on prostate cancer cells. Cell MRI Imaging demonstrated that ProCA1.GRP(52) grafted between Lys51 and Ser52 had better targeting capability than C-terminal one. Administration of ProCA1.GRP into xenograft tumor model enhances the contrast in the GRPR+ prostate tumor under MRI and optical imaging. Study demonstrated a potential application for disease marker targeted MR imaging by using our developed protein contrast agent.
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Filali, Bilal. "Caractérisation des ondes radar de surface par la simulation numérique et les mesures GRP pour l'auscultation en génie civil." Thèse, Université de Sherbrooke, 2014. http://hdl.handle.net/11143/6635.
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Les ondes radar de surface sont définies comme étant la partie des ondes de volume qui se propage sur l'interface entre deux milieux. Cette partie du milieu de propagation est la plus ciblée par l'auscultation en génie civil. Une étude de caractérisation de ces ondes s'avère alors indispensable et préalable à toute mesure les employant, ce qui représente l'objectif de cette Thèse. On procède d'abord à la caractérisation des ondes radar de surface (ORS) par la simulation numérique à des fréquences centrées à 300, 400, et 500 MHz. Les ORS sont visualisées dans un radargramme et leurs temps d'arrivée et amplitudes sont obtenus afin de déduire de deux différentes façon leur profondeur de propagation. On a montré théoriquement que les ondes de surface couvrent suffisamment de volume du milieu pour le contrôle non destructif en génie civil. De plus, on montre que cette profondeur augmente lorsque les antennes réceptrice et émettrice sont plus écartées. Une variation significative de cette profondeur en fonction de la fréquence est également observée et expliquée. Cependant, afin de rendre possible ce travail de modélisation, une méthode de simulation numérique est développée dans le cadre de cette Thèse. Il s'agit d'une méthode nouvelle de simulation de la réponse GPR qui a l'avantage important de s'adapter facilement aux modèles du génie civil, par rapport à celles déjà appliquées dans le domaine du GPR pour la géophysique. La simulation consiste à modéliser une radiation d'antenne à travers le milieu ausculté afin d'obtenir la réponse GPR. On montre que la méthode des éléments finis (FEM) est la plus avantageuse pour la simulation de la réponse GPR lorsqu'appliquée en génie civil. En raison de sa flexibilité de maillage, le temps de calcul est considérablement optimisé notamment lorsqu'on considère la nature des matériaux de ce domaine. La résolution des modèles se faisant à une seule fréquence à la fois, les milieux dispersifs sont modélisés plus aisément suivant cette méthode. Pour l'analyse des ORS, le traitement du signal dans le domaine temporel est une procédure indispensable pour. les objectifs en question. Une méthode de traitement de signal est alors développée basée sur la dérivée de la phase spectrale. Il sera prouvé que cette méthode est la seule valable pour le calcul des temps d'arrivée d'un signal quelconque de radiation. Une méthode d'inversion est appliquée pour calculer l'indice de réfraction, qui est trouvé clairement proche à sa valeur prévue. La légère différence est expliquée par l'incertitude' déduite de la distribution normale des fluctuations de la phase spectrale. Finalement, pour confirmer la valeur de la profondeur de propagation des ORS, des essais de laboratoire sont élaborés sur un banc de sable de dimensions adéquates et monté de façon à permettre le contrôle de sa teneur en eau. La variation de la teneur en eau dans le sable et son gradient surtout seront utilisés pour distinguer la profondeur couverte par ces ondes dans leur propagation. L'étude démontre que les ondes de surface peuvent couvrir toutes les profondeurs visées par les tests non destructifs en génie civil, ce qui les rend intéressante à exploiter dans ce domaine. On parle d'une valeur entre 10 cm et prés de 30 cm de profondeur de propagation, qui variable de façon contrôlable.
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Oliveira, Sílvia Helena Soares. "Mecanismos moleculares envolvidos na ação modulatória do receptor GRP sobre a consolidação da memória na área Ca1 do hipocampo." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2006. http://hdl.handle.net/10183/17318.
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O peptídeo liberador da gastrina (gastrin-releasing peptide, GRP), pertencente à família dos peptídeos semelhantes à bombesina, e seus receptores estão presentes em todo o sistema nervoso central, em particular em áreas límbicas cerebrais como o hipocampo e a amídala, as quais estão envolvidas de forma importante na regulação emocional, na função cognitiva e em transtornos neuropsiquiátricos e neurodegenerativos. Há estudos sugerindo que receptores GRP podem ter um papel na regulação da plasticidade sináptica, de respostas emocionais e da formação da memória. Apesar disso, esse sistema tem sido relativamente pouco estudado quanto a seu papel na função cerebral e não são conhecidos os mecanismos celulares envolvidos na transdução de sinal ativada por receptores GRP no sistema nervoso. Estudos em outros tipos de células sugerem que a ativação de receptores GRP pode levar a uma ativação das vias de transdução de sinal mediadas por proteína cinase C (protein kinase C, PKC) e pela proteína cinase ativada por mitógeno (mitogen-activated protein kinase, MAPK). O envolvimento da via da adenilato ciclase/AMPc/proteína cinase A (protein kinase A, PKA) é controverso. Por outro lado, já está estabelecido que as vias de sinalização da PKC, MAPK e PKA estão envolvidas de forma crucial na formação da memória emocional na área CA1 do hipocampo dorsal. Assim, é possível que a ativação de receptores GRP module a memória através da ativação de uma ou mais dessas vias. No presente trabalho, propomos uma abordagem farmacológica de investigação, utilizamos para isso, um modelo bem estabelecido de memória emocional em roedores, para analisar as interações entre receptores GRP e os eventos biológicos que se seguem à ativação do receptor, ou seja, a ativação de cascatas de sinalização neuronal mediadas por proteínas cinases, na região CA1 do hipocampo dorsal. Ratos Wistar machos foram tratados com uma infusão bilateral de agonista do GRPR, bombesina, no hipocampo dorsal imediatamente após o treino em esquiva inibitória. Doses intermediárias de bombesina induziram uma facilitação, enquanto doses mais altas prejudicaram a retenção da memória medida 24 horas após o treino. A facilitação da memória induzida pela bombesina foi prevenida por infusões pré-treino de um antagonista GRP ou de inibidores de PKC, MAPK ou PKA, mas não por um antagonista do receptor de neuromedina B (NMB). Os resultados indicam que a modulação da consolidação da memória por GRPRs hipocampais depende das vias da PKC, MAPK e PKA.Gastrin-releasing peptide (GRP), a bombesin-like peptide, and their receptors are gifts in all the central nervous system, particular in cerebral limbic areas as hippocampus and amigdala, which are involved in an important way in the emotional regulation, cognitive function and neurodegenerative and neuropsychiatric disorders. Studies suggest that GRPR can act in synaptic plasticity regulation, emotional answers and memory formation. Although this, this system has been relatively little studied how much its paper in the cerebral function and the involved cellular mechanisms in the transdução of signal are not known activated for receivers GRP in the nervous system. Studies in other cell types suggest that activation of GRPR can active signal transduction pathways mediated by protein cinase C (protein kinase C, PKC) and mitogen-activated protein kinase (MAPK). The envolvement of protein kinase A (PKA) pathways are controversial. Already it is established that PKC, MAPK and PKA signal pathways are involved of crucial form in emotional memory formation in CA1 area of dorsal hippocampus. Thus, it is possible that the activation of GRPR modulates the memory through the activation of one or more than these ways. In present study, we propose an pharmacological investigation, using an established emotional memory model in rodents, to analyze the interactions between GRPRs and the biological events following to the receptores activation in other words, the neuronal sign cascades activation mediated by proteins kinases, in CA1 hippocampus area. Male Wistar rats received bilateral infusions of the GRPR agonist bombesin into the dorsal hippocampus immediately after inhibitory avoidance training. Intermediate doses of bombesin enhanced, whereas a higher doses impaired 24-h memory retention. The bombesin-induced memory enhancement was prefented by pretraining infusions of a GRPR antagonist or inhibitors of PKC, MAPK and PKA, but not a neuromedin B (NMB) antagonist. We conclude that memory modulation by hippocampal GRPRs is mediated by the PKC, MAPK and PKA pathways.
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Giacchetti, Sylvie. "Facteurs de croissance et cancers du sein : étude du récepteur à la bombesine-GRP (Gastrin Releasing Peptide) in vitro." Paris 6, 1990. http://www.theses.fr/1990PA062036.
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Tsai, Liren. "SHOCK WAVE STRUCTURE AND SPALL STRENGTH OF LAYERED HETEROGENEOUS GLASS/POLYMER COMPOSITE." Case Western Reserve University School of Graduate Studies / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=case1138377998.
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Jaeger, Nat?lia. "Investiga??o do efeito proliferativo e migrat?rio do pept?deo liberador de gastrina (GRP) sobre uma linhagem de adenocarcinoma pulmonar." Pontif?cia Universidade Cat?lica do Rio Grande do Sul, 2014. http://tede2.pucrs.br/tede2/handle/tede/5511.
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Previous issue date: 2014-12-10Lung cancer is the most commonly diagnosed type of cancer and the leading cause of cancer related mortality in the world, causing nearly one million deaths per year. Among all histological types, adenocarcinoma is the most frequent one (75-80%). Gastrin-releasing peptide (GRP) is considered to be a mitogen, capable of inducing cell proliferation, since it is involved in fetal lung development. This neuropeptide had its effect on tumor growth first identified in human cells of small cell lung cancer, acting as an autocrine growth factor for tumor tissues by binding to its receptor GRPR. The receptor has been found in many tumor types such as prostate, breast, stomach, pancreas and colon. Moreover, this peptide acts as a morphogen, in angiogenesis and is related to inflammatory processes and in the regulation of cells of the immune system. Furthermore, asymptomatic smokers have high levels of GRP in bronchoalveolar lavage and urine. However, little is known about its effects in tumorigenesis and metastasis, and which molecular mechanisms and signaling pathways are responsible for the effects found. Our group demonstrated recently that GRP could act as a chemotactic molecule for neutrophils. Thus, we hypothesized that GRP could be also a chemotactic stimulus to tumor cells expressing the GRPR. In this study, we tested this hypothesis by examining the effect of GRP on proliferation, survival and migration of cells from the adenocarcinoma cell line A549, seeking to identify the mechanisms of action of this peptide. These cells express high levels of GRPR and treatment with GRP leads to activation of kinases such as AKT and ERK1/2 that are involved in the cellular processes mentioned. Our results suggest that GRP is a migratory stimulus to these cells without evidence of significant effect on their proliferation or survival to treatment with the chemotherapy drug cisplatin (CDDP). Nonetheless, they become more sensitive to CDDP when the drug is combined with a GRPR antagonist. Thus, we believe that future studies should consider a possible role for GRP in metastasis of NSCLC.
O c?ncer de pulm?o ? o tipo de c?ncer que mais comumente diagnosticado e o que mais mata no mundo levando a quase 1 milh?o de mortes por ano. Entre todos os tipos histol?gicos, o adenocarcinoma ? o mais frequente (75-80%). O pept?deo liberador de gastrina (GRP) ? considerado um agente mitog?nico, capaz de induzir a prolifera??o celular, uma vez que est? envolvido no desenvolvimento fetal dos pulm?es. Este pept?deo teve sua a??o sobre o crescimento tumoral primeiramente identificada em c?lulas humanas de c?ncer de pulm?o de pequenas c?lulas, atuando como fator aut?crino de crescimento de tecidos e tumores atrav?s da liga??o ao seu receptor GRPR. Este receptor foi encontrado em diversos tipos de tumores como pr?stata, mama, est?mago, p?ncreas e c?lon. Al?m disso, este pept?deo atua como um morf?geno, na angiog?nese e, est? relacionado a processos inflamat?rios e na regula??o de c?lulas do sistema imune. E, fumantes assintom?ticos possuem altos n?veis de GRP no lavado broncoalveolar e na urina. No entanto, pouco se conhece sobre os seus efeitos na tumorig?nese e met?stase e, quais os mecanismos moleculares e as vias de sinaliza??o que s?o respons?veis pelos efeitos encontrados. Nosso grupo demonstrou, recentemente, que o GRP pode atuar como uma mol?cula quimiot?tica para neutr?filos. Desta forma, hipotetizamos que o GRP poderia constituir num estimulo quimiot?tico tamb?m para as c?lulas tumorais que express?o o GRPR. Neste trabalho, testamos essa hip?tese, analisando o efeito do GRP sobre a prolifera??o, sobreviv?ncia e migra??o de c?lulas da linhagem de adenocarcinoma A549, buscando identificar mecanismos de a??o desse pept?deo. Esta linhagem expressa altos n?veis de GRPR. O tratamento com GRP leva a ativa??o de quinases como a AKT e ERK1/2 que est?o envolvidas nestes processos celulares. Nossos resultados sugerem que o GRP ? principalmente um est?mulo migrat?rio para estas c?lulas, sem evid?ncias de efeito significativo sobre a sua prolifera??o ou sobreviv?ncia ao tratamento com a droga quimioter?pica cisplatina, mas tornam-se mais sens?veis quando a droga ? combinada com um antagonista do GRPR. Dessa forma, acreditamos que estudos futuros devam considerar um poss?vel papel para o GRP na met?stase.
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Cruz, Luciane Beitler da. "Efeitos do antagonista dos receptores Gastrin-Releasing Peptide (GRP) sobre peso, alimentação, parâmetros metabólicos, bioquímicos e composição corporal de ratos wistar." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2014. http://hdl.handle.net/10183/110313.
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Introdução e objetivo: Gastrin-releasing peptide (GRP) está envolvido em diversas funções cerebrais e gastrointestinais, incluindo secreção pancreática, liberação de hormônios peptídeos gastrointestinais e redução da ingestão alimentar. O objetivo deste estudo é testar os efeitos da injeção intraperitoneal do antagonista do receptor GRP sobre o peso, ingestão alimentar, parâmetros metabólicos e bioquímicos e composição corporal. Métodos: Foram utilizados 35 ratos Wistar adultos jovens, submetidos a uma perda ponderal mínima de 7%, divididos em quatro grupos: Grupo Controle (G0) que recebeu injeção de solução salina; Grupo 1 (G1) que recebeu 0,1 mg/kg de RC-3095; Grupo 2 (G2) que recebeu 0,3 mg/kg de RC-3095 e Grupo 3 (G3) que recebeu 1,0 mg/kg de RC-3095 durante 14 dias. Resultados: A variação da média diária de ingestão alimentar foi estatisticamente diferente entre os grupos (F: 3,139; df: 3; P = 0,039) e o G2, que recebeu a dose intermediária de 0,3 mg/kg de RC-3095, mostrou uma ingestão alimentar maior do que o G0 (P = 0,041). Houve um aumento similar do peso, de aproximadamente 22% (F: 0,572; df: 3; P = 0,638), assim como uma média de peso similar dos animais (F: 1,145; df: 9,685; P = 0,338) entre os grupos durante o período do estudo. Porém, a média de peso do G2 foi mais alta do que a média de peso dos animais do G0 (P = 0,042). Ao final do estudo, nenhuma diferença foi observada entre os grupos no total de massa magra ou de massa gorda da carcaça, fígado e pele dos animais. Comparando os níveis séricos de albumina, amilase, glicose, colesterol total, HDL-colesterol e interleucina-6 do Dia 1 (D1) para o Dia 14 (D14), não houve diferença estatisticamente relevante entre os grupos. Entretanto, o nível médio de triglicerídeos no G2 mostrou um aumento maior quando comparado ao G0 (P = 0,038). Conclusões: Neste estudo, a injeção da dose intermediária do antagonista do receptor GRP, o RC-3095 (0,3 mg/kg/dia), em ratos Wistar adultos jovens saudáveis submetidos a perda ponderal, interferiu na ingestão alimentar e no peso médio. Nenhum efeito sobre o ganho de peso, composição corporal ou parâmetros metabólicos e bioquímicos foi observado, exceto um aumento maior do nível sérico de triglicerídeos. Estes resultados demonstram alguns dos efeitos fisiológicos do GRP sobre a ingestão alimentar e peso, ampliando possibilidades de futuros estudos sobre fome, saciedade e metabolismo de macronutrientes ou em animais submetidos a uma condição de estresse maior, como o câncer.Introduction and Objective: Gastrin-releasing peptide (GRP) is involved in several brain and gastrointestinal functions, including pancreatic secretion, gastrointestinal peptide hormone release, and reduction of food intake. We tested the effects of an intraperitoneal injection of the GRP receptor (GRPR) antagonist RC-3095 on weight, food intake, biochemical metabolic parameters, and body composition. Methods: Thirty-five young adult male Wistar rats, submitted to a minimal weight loss of 7%, were divided into four groups: the control group (G0) received saline; Group 1 (G1) received 0.1 mg/kg RC-3095; Group 2 (G2) received 0.3 mg/kg RC-3095; and Group 3 (G3) received 1.0 mg/kg RC-3095 for 14 days. Results: The mean daily variation of food intake was statistically different between the groups (F: 3.139; df: 3; P = 0.039); and G2, which received the intermediate dose of 0.3 mg/kg RC-3095, showed a greater food intake than G0 (P = 0.041). There was a similar increase in weight, approximately 22% (F: 0.572; df: 3; P = 0.638), as well as a similar mean animal weight (F: 1.145; df: 9.685; P = 0.338) between the groups during the study period. However, the mean weight of G2 animals was more than the mean weight of G0 animals (P = 0.042). At the end of the study, no difference was observed between the groups in terms of the total lean mass or fat mass from the rat carcass, liver, and skin. Comparing the serum levels of albumin, amylase, glucose, total cholesterol, high-density lipoprotein (HDL) cholesterol, and interleukin (IL)-6 from day 1 (D1) to D14, there were no statistically relevant differences between the groups. However, the mean triglyceride level in G2 compared to G0 showed a greater increase (P = 0.038). Conclusion: In this study, the injection of an intermediate dose of GRPR antagonist RC- 3095 (0.3 mg/kg/day) into healthy young adult Wistar rats submitted to weight loss affected food intake and the mean weight. No effects on weight gain, body composition, or biochemical metabolic parameters were observed, except for a great increase in the serum triglyceride levels. These results demonstrate some physiological effects of GRP on food intake and weight, expanding the possibilities of future studies on hunger/satiety and macronutrient metabolism as well as highly stressful conditions like cancer.
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Elder, David James, and d. elder@crc-acs com au. "Optimisation of parametric equations for shock transmission through surface ships from underwater explosions." RMIT University. Aerospace, Mechanical and Manufacturing Engineering, 2006. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20080212.105012.
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Currently shock effects on surface ships can be determined by full scale shock trials, Finite Element Analysis or semi empirical methods that reduce the analytical problem to a limited number of degrees of freedom and include hull configurations, construction methods and materials in an empirical way to determine any debilitating effects that an explosion may have on the ship. This research has been undertaken to better understand the effect of hull shape on surface ships' shock response to external underwater explosions (UNDEX). The study is within the semi empirical method category of computations. A set of simple closed-form equations has been developed that accurately predicts the magnitude of dynamic excitation of different 2- D rigid-hull shapes subject to far-field UNDEX events. This research was primarily focused on the affects of 2-D rigid hull shapes and their contribution to global ship motions. A section of the thesis,
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Alibabaei, Navid. "Wireless Mesh Networks: a comparative study of Ad-Hoc routing protocols toward more efficient routing." Thesis, Blekinge Tekniska Högskola, Institutionen för kommunikationssystem, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-1023.
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Each day, the dream of seamless networking and connectivity everywhere is getting closer to become a reality. In this regard, mobile Ad-Hoc networks (MANETs) have been a hot topic in the last decade; but the amount of MANET usage nowadays confines to a tiny percentage of all our network connectivity in our everyday life, which connectivity through infrastructured networks has the major share. On the other hand, we know that future of networking belongs to Ad-Hocing , so for now we try to give our everyday infrastructure network a taste of Ad-Hocing ability; these types of networks are called Wireless Mesh Networks (WMN) and routing features play a vital role in their functionality. In this thesis we examine the functionality of 3 Ad-Hoc routing protocols known as AODV, OLSR and GRP using simulation method in OPNET17.5. For this goal we set up 4 different scenarios to examine the performance of these routing protocols; these scenarios vary from each other in amount of nodes, background traffic and mobility of the nodes. Performance measurements of these protocols are done by network throughput, end-end delay of the transmitted packets and packet loss ratio as our performance metrics. After the simulation run and gathering the results we study them in a comparative view, first based on each scenario and then based on each protocol. For conclusion, as former studies suggest AODV, OLSR and DRP are among the best routing protocols for WMNs, so in this research we don’t introduce the best RP based on the obtained functionality results, instead we discuss the network conditions that each of these protocols show their best functionality in them and suggest the best routing mechanism for different networks based on the analysis from the former part.
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Zahir, Aishath Zehereen. "Degradation of e-glass fibre in selected organic acids." Thesis, Curtin University, 2008. http://hdl.handle.net/20.500.11937/1654.
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E-glass has been widely used as a reinforcing material for years, especially as a plastic reinforcer in the production of GRP (Glass Reinforced Plastic). Failure of GRP materials under stress came in to the picture quite recently. Since then studies have been conducted in an attempt to understand the causes and the underlying behaviour.Except for the last section of the research (analysis using a kinetic approach) where glass fibre was cut out to weigh approximately 1.0g, standard sized specimens were soaked in the required acid solutions of desired concentrations for varying temperatures and time frames. Wherever tensile strength retention was measured, LLOYD instrument was employed. Leaching of the cations were analysed using Inductively Coupled Plasma – Optical Emission Spectroscopy (ICP-OES and also know and ICP-AES).The scope of this project can be divided in to four sections; first section involved investigating the effects of malonic acid. The study of malonic acid was narrowed to investigating the trend in strength retention. A rapid strength loss was observed initially followed by a much steady decline in the strength. However the continuation of the loss of strength was unmistakable throughout the time period of exposure. Furthermore, temperature can be observed as a facilitating factor in this degradation reaction.Secondly the corrosive effect of glyoxylic acid on E-glass fibre was studied. This was explored at two different temperatures for two specific time frames using various concentrations of the acid of interest. The influence of this acid on the glass fibre was found out in terms of strength retention and loss of cations from the glass matrix. The mildness of this acid was accentuated by the fact that 70% or more of the strength was retained at all the conditions employed. A minima in strength retention was observed at 2M acid concentration similar to the trends observed in the past (Betz and Jones 2003 and Jones and Chandler 1986). Leaching of cations reflected this trend. The large strength retention could be related to the fewer amounts of Ca and K leached from the glass matrix (Kumosa and Qui, 1997). Similar to malonic acid, an unusually large amount of B was leached out that could be due to the favourable orientation of the anion with the trivalent ions during the complex formation. Yet again temperature was found to enhance the degradation process.Next the extent of passivation (if any) showed by malonic acid was investigated using E-glass fibre pre-treated in 5M malonic acid and post treated in known corrosive acids hydrochloric acid and oxalic acid. Passivation of malonic acid was put to test through examination of strength retention of the fibres under these conditions. This segment was carried out as an extension of a finding (a behaviour synonymous to passivation) shown by malonic that surfaced the previous year by the present researcher. Increasing the pre-treatment time showed a great improvement in the retained strength for all the post-treatment acid mediums. Furthermore, while Jones and Betz (2004) featured 20-40% strength retention within a short time frame in 3M HCl, the immense amount of strength retention (60-70%) preceding pre-treatment should definitely be noted. Similarly strength retention of about 80% was observed when post-treated with the severely corrosive oxalic acid. Hence its is clear that passivation can be induced through prolonged pre-treatment in 5M malonic acid that could inhibit the attack of corrosive acid at least for a period of time.The last fragment of the study focussed on understanding and working out the mechanism behind the reactions between the E-glass fibre and acid medium in terms of kinetics. The acids utilized were 1.5M malonic acid and 3M glyoxylic acid and the assessments were made through the analysis of the weight changes brought about by the acid medium at various temperatures and time frames. In addition leaching patterns of cations were evaluated as this could contribute in achieving the objective. Maximum weight loss reached 4% in glyoxylic acid while that for malonic acid exceeded 20%. The general trend was that the glass fibres lost weight in both acids for a period of time followed by an evident weight gain. Furthermore the weight loss results fit the first order rate law. While the leaching of cations reflects the weight loss for the shorter time frames, steady loss of ions was visible even for the longer time frames where the weight has increased. The weight gain could be explained in terms of binding of anions to certain cations on the glass surface, accounting for the hindrance in the loss of cations at the longer time frames as well. About 50% of weight loss was associated to Ca while 20% was to Al, leaving 6% to B where as the rest of the ions had shown almost insignificant contribution to the weight loss.
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Ghazanfar, Katrina. "BIOINFORMATIC ANALYSIS OF A MAMMALIAN BIP GENE FOR INSERTION INTO GREEN ALGAE AND COMPARISON OF ITS POSSIBLE EFFECTS ON THE SYNTHESIS OF A MAMMALIAN ANTIBODY." VCU Scholars Compass, 2004. http://scholarscompass.vcu.edu/etd/36.
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This dissertation describes a study utilizing bioinformatics to analyze homologues of a molecular chaperone, glucose-regulated protein 78 (grp 78), also known as BiP. The selected homologous proteins originate from organisms of infinitely diverse genera. Comparisons of protein sequence yielded the first clues of a common ancestry among these proteins. Furthermore, protein molecular weights, isoelectric points, N-terminal amino acids and half-lives of a known homolog and a non-homologous protein were examined. Additionally, electroporation, a state-of-the-art plasmid insertion technique, was explored using Chlamydomonas reinhardtii, a green alga, as the recipient of a parent plasmid, pSP124S. Distinctive hypertonic solutions and three separate field strengths were used in the plasmolysis of the cell wall of C. reinhardtii and subsequent electroporation, respectively. The number of transformants was tallied to evaluate which electroporation condition would yield the most transformed colonies. We had two discrete hypotheses: 1) that a structurally and functionally similar protein to glucose-regulated protein 78 exists across a wide spectrum of organisms and 2) that Chlamydomonas reinhardtii could be successfully transformed with pSP124S under certain electroporation conditions. The bioinformatics investigation revealed that analogous proteins to Human GRP 78 existed in Mus musculus (mouse), Rattus norvegicus (rat), Gallus domesticus (chicken), Gallus domesticus (chicken), Mesocricetus auratus (golden hamster), Bos taurus (cow), Xenopus laevis (frog), and Spinacia oleracea (spinach). Moreover, these homologous proteins more likely have a common evolutionary origin.
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Zahir, Aishath Zehereen. "Degradation of e-glass fibre in selected organic acids." Curtin University of Technology, Department of Applied Chemistry, 2008. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=128425.
Full textAbstract:
E-glass has been widely used as a reinforcing material for years, especially as a plastic reinforcer in the production of GRP (Glass Reinforced Plastic). Failure of GRP materials under stress came in to the picture quite recently. Since then studies have been conducted in an attempt to understand the causes and the underlying behaviour.Except for the last section of the research (analysis using a kinetic approach) where glass fibre was cut out to weigh approximately 1.0g, standard sized specimens were soaked in the required acid solutions of desired concentrations for varying temperatures and time frames. Wherever tensile strength retention was measured, LLOYD instrument was employed. Leaching of the cations were analysed using Inductively Coupled Plasma – Optical Emission Spectroscopy (ICP-OES and also know and ICP-AES).
The scope of this project can be divided in to four sections; first section involved investigating the effects of malonic acid. The study of malonic acid was narrowed to investigating the trend in strength retention. A rapid strength loss was observed initially followed by a much steady decline in the strength. However the continuation of the loss of strength was unmistakable throughout the time period of exposure. Furthermore, temperature can be observed as a facilitating factor in this degradation reaction.
Secondly the corrosive effect of glyoxylic acid on E-glass fibre was studied. This was explored at two different temperatures for two specific time frames using various concentrations of the acid of interest. The influence of this acid on the glass fibre was found out in terms of strength retention and loss of cations from the glass matrix. The mildness of this acid was accentuated by the fact that 70% or more of the strength was retained at all the conditions employed. A minima in strength retention was observed at 2M acid concentration similar to the trends observed in the past (Betz and Jones 2003 and Jones and Chandler 1986). Leaching of cations reflected this trend. The large strength retention could be related to the fewer amounts of Ca and K leached from the glass matrix (Kumosa and Qui, 1997). Similar to malonic acid, an unusually large amount of B was leached out that could be due to the favourable orientation of the anion with the trivalent ions during the complex formation. Yet again temperature was found to enhance the degradation process.
Next the extent of passivation (if any) showed by malonic acid was investigated using E-glass fibre pre-treated in 5M malonic acid and post treated in known corrosive acids hydrochloric acid and oxalic acid. Passivation of malonic acid was put to test through examination of strength retention of the fibres under these conditions. This segment was carried out as an extension of a finding (a behaviour synonymous to passivation) shown by malonic that surfaced the previous year by the present researcher. Increasing the pre-treatment time showed a great improvement in the retained strength for all the post-treatment acid mediums. Furthermore, while Jones and Betz (2004) featured 20-40% strength retention within a short time frame in 3M HCl, the immense amount of strength retention (60-70%) preceding pre-treatment should definitely be noted. Similarly strength retention of about 80% was observed when post-treated with the severely corrosive oxalic acid. Hence its is clear that passivation can be induced through prolonged pre-treatment in 5M malonic acid that could inhibit the attack of corrosive acid at least for a period of time.
The last fragment of the study focussed on understanding and working out the mechanism behind the reactions between the E-glass fibre and acid medium in terms of kinetics. The acids utilized were 1.5M malonic acid and 3M glyoxylic acid and the assessments were made through the analysis of the weight changes brought about by the acid medium at various temperatures and time frames. In addition leaching patterns of cations were evaluated as this could contribute in achieving the objective. Maximum weight loss reached 4% in glyoxylic acid while that for malonic acid exceeded 20%. The general trend was that the glass fibres lost weight in both acids for a period of time followed by an evident weight gain. Furthermore the weight loss results fit the first order rate law. While the leaching of cations reflects the weight loss for the shorter time frames, steady loss of ions was visible even for the longer time frames where the weight has increased. The weight gain could be explained in terms of binding of anions to certain cations on the glass surface, accounting for the hindrance in the loss of cations at the longer time frames as well. About 50% of weight loss was associated to Ca while 20% was to Al, leaving 6% to B where as the rest of the ions had shown almost insignificant contribution to the weight loss.
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Åström, Erik. "Is there an economic value for elite sports? : The case of Swedish Hockey League." Thesis, Linnéuniversitetet, Institutionen för nationalekonomi och statistik (NS), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-65826.
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The economic value of sport has long been an interesting subject to study. Proponents arguing there is big monetary return for a region hosting a professional sports team. However, majority of studies done on the subject point in the same direction where it seems economic return are negligible. Researchers even argue there is rather an alternative cost where money could be better spent on other social structure such as education and health care. The value of sport creates both direct and indirect effect. In this essay I will look at whether there could be any indirect spillover effects from hosting a hockey team in the highest league. Due to its simplicity, a difference-in-difference (DiD) method will be used on municipalities hosting a hockey team. This when looking at Gross Regional Product (GRP), unemployment rate and population growth to municipalities without a hockey team. The results of this study are ambiguous and hard to interpret when sign on coefficient differ between variables and municipalities. However, there seem to be a correlation between lower unemployment rate and population growth and an increase in GRP when a team is qualifying to SHL. It cannot be determined whether this depend on economic growth or success of their professional sports team.
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Yuan, Fuping. "PLATE IMPACT EXPERIMENTS TO INVESTIGATE DYNAMIC SLIP, DEFORMATION AND FAILURE OF MATERIALS." Case Western Reserve University School of Graduate Studies / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=case1193161550.
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