Academic literature on the topic 'Polyp growth'
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Journal articles on the topic "Polyp growth"
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Zulfikar, Zulfikar, Dedi Soedharma, Zulfigar Yasin, and Aileen Tan Shau Hwai. "Fragmentation method of coral (Caulastrea furcata) for growth measured at controlling condition." Acta Aquatica: Aquatic Sciences Journal 1, no. 1 (October 30, 2014): 20. http://dx.doi.org/10.29103/aa.v1i1.293.
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The objective of the research are: (1) to analyze the water quality condition of water circulation system at laboratory and (2) to measure the growth (length and height) and survival rate of Caulastrea furcata which was fragmented at the laboratory. The water quality condition at the laboratory showed that every parameter has normal value in which organism can live and grow. Natural feed such as Copepoda and Nannoclhoropsis were also cultured at the laboratory as food for the coral. Transplantation was done by cutting the colony of coral or by breaking the branch of coral into pieces from every kind of coral spesies and placed those on artificial substrate made from ceramic bricks. Cutting process was done after the acclimatization process. Fragmentation treatment of C. furcata become 1 polyp, 2 polyp, 3 polyp and 4 polyp that was reared on circulation system did not give significant impact on height and length growth after 160 days. Mean of growth length of C. furcata on treatment 1, 2, 3 and 4 polyps in every month after 160 days was 1.64 mm, 1.55 mm, 1.42 mm and 1.08 mm, respectively, whereas mean of growth broad was 0.71 mm, 0.82 mm, 0.51 mm and 0.62 mm, respectively. Fragmentation treatment of C. furcata become 1 polyp was best length if compare other treatment.Tujuan penelitian ini adalah: (1) menganalisis kondisi kualitas air pada system sirkulasi air di laboratorium dan (2) mengukur pertumbuhan (panjang dan tinggi) dan tingkat kelulushidupan Caulastrea furcate yang telah difrakmentasi di laboratorium. Nilai kualitas air menunjukkan bahwa setiap parameter adalah normal dan dapat mendukung kehidupan dan pertumbuhan organisme. Pakan alami seperti Copepoda dan Nannoclhoropsis yang juga dikultur di laboratorium sebagai pakan karang. Tansplantasi dilakukan melalui pemotongan koloni karang pada bagian cabang karang kedalam bagian kecil dari setiap spesies karang dan ditempatkan pada subtrak buatan yang dibuat dari keramik. Proses pemotongan dilakukan setelah proses aklimatisasi dilakukan. Perlakuan frakmentasi C. furcate menjadi 1 polip, 2 polip, 3 polip dan 4 polip kemudian didedahkan dalam air berskirkulasi tidak memberikan efek yang signifikan terhadap pertumbuhan tinggi dan panjang setelah 160 hari. Rata-rata pertambahan lebar pada perlakuan 1, 2, 3 dan 4 polip pada setiap bulan setelah 160 hari adalah 1.64 mm, 1.55 mm, 1.42 mm dan 1.08 mm. dimana rata-rata pertumbuhan tinggi secara berurutan adalah 0.71 mm, 0.82 mm, 0.51 mm dan 0.62 mm. Perlakuan frakmentasi 1 polip pada C. furcate menghasilkan panjang terbaik dibandingkan perlakuan lainnya.
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Lin, Chiahsin, Chia-Ming Kang, Chih-Yang Huang, Hsing-Hui Li, and Sujune Tsai. "Study on the Development and Growth of Coral Larvae." Applied Sciences 12, no. 10 (May 23, 2022): 5255. http://dx.doi.org/10.3390/app12105255.
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Studies on the early development of corals are required for academic research on coral reefs and applied reef conservation, but the interval between observations is usually weeks or months. Thus, no study has comprehensively explored the development of coral larvae after settlement. This study observed Galaxea fascicularis, Mycedium elephantotus, Pocillopora verrucosa, and Seriatopora caliendrum larvae after settlement, including their growth process and the formation of tentacles, skeletons, and polyps. The G. fascicularis and M. elephantotus polyps exhibited the skeleton-over-polyp mechanism, whereas the P. verrucosa and S. caliendrum polyps exhibited the polyp-over-skeleton mechanism. During asexual reproduction, the Symbiodiniaceae species clustered on the coenosarc, resulting in polyp development and skeletal growth. M. Elephantotus was unique in that its tentacles were umbrella-shaped, and its polyp growth and Symbiodiniaceae species performance during asexual reproduction differed from those of the other three corals. Although both P. verrucosa and S. caliendrum have branching morphologies, their vertical development stages were dissimilar. S. caliendrum relied on the mutual pushing of individuals in the colony to extend upward, whereas P. verrucosa had a center individual that developed vertically. The findings of this study can serve as a reference for future research on coral breeding, growth, and health assessments.
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Wilson, L. S., and J. Lightwood. "Model of estimated rates of colorectal cancer from polyp growth by year of surveillance." Journal of Medical Screening 8, no. 4 (December 1, 2001): 187–96. http://dx.doi.org/10.1136/jms.8.4.187.
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OBJECTIVE:Most studies show protective effects of non-steroidal anti-inflamatory drugs (NSAIDs) against polyps and colorectal cancers (CRCs) of up to 50%. Current models are unable to directly estimate changes in effects of chemoprevention on CRCs. The purpose is to develop a model to examine effects of changes in growth rates of polyps on surveillance intervals and risk of CRC . METHODS:The growth model simulates 500 people after polypectomy, estimating number and size of polyps annually over 10 years. Each polyp is assigned a random growth rate consistent with distributions of empirically observed growth assumed to follow a log linear model. Rates of CRC were calculated from largest polyps distributed to people. RESULTS:Simulated distributions of polyps and CRCs closely match empirical estimates which confirms the usefulness of the model. If polyp growth is 25% of normal, the number of cancers by year 10 after index colonoscopy decrease from 146 to only 57/100 000 for those in risk group 0 (no polyps at index colonoscopy) and from 840 to 124/100 000 for those of risk group 3 (4 or more polyps). CONCLUSIONS:This is the first model based on polyp growth rates. The CRC rates suggest that for those with no polyps on index colonoscopy, surveillance may be as for people of average risk (7–10 years), whereas those with one polyp or more need more surveillance (2–5 years). The use of the model is the indication that surveillance intervals could be increased by as much as 2–10 years if the growth rates of polyps are slowed.
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Gösser, Fabian, Arne Raulf, Axel Mosig, Ralph Tollrian, and Maximilian Schweinsberg. "Signaling pathways of heat- and hypersalinity-induced polyp bailout in Pocillopora acuta." Coral Reefs 40, no. 6 (November 9, 2021): 1713–28. http://dx.doi.org/10.1007/s00338-021-02191-x.
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AbstractPolyp bailout is a drastic response to acute stress where coral coloniality breaks down and polyps detach. We induced polyp bailout in Pocillopora acuta with heat stress and tested for differential gene expression using RNAseq and a qPCR assay. Furthermore, we induced polyp bailout with hypersalinity and compared the results to identify stressor-independent signals and pathways active during polyp bailout. Both stressors led to the onset of polyp bailout and the detachment of vital polyps. We observed activation of microbe-associated molecular pattern receptors and downstream signaling pathways of the innate immune system. Further, we detected growth factors and genes active during Wnt-signaling potentially contributing to wound healing, regeneration, and proliferation. Upregulation of several genes encoding for matrix metalloproteinases and the fibroblast growth factor signaling pathway are the most likely involved in the remodeling of the extracellular matrix, as well as in the detachment of polyps from the calcareous skeleton during polyp bailout. Expression of genes of interest in our qPCR assay of vital polyps from our heat-stress experiment, showed a trend for a normalization of gene expression after polyp bailout. Our results provide new insights into the signaling cascades leading to the observed physiological responses during polyp bailout. Comparison between the two stressors showed that certain signaling pathways are independent of the stressor and suggested that polyp bailout is a general response of corals to acute stress. Furthermore, immune system responses during polyp bailout indicate that microbe-associated partners of corals may lead to the polyp bailout response.
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Baltgalvis, Kristen A., Franklin G. Berger, Maria Marjorette O. Peña, J. Mark Davis, and James A. Carson. "Effect of exercise on biological pathways in ApcMin/+ mouse intestinal polyps." Journal of Applied Physiology 104, no. 4 (April 2008): 1137–43. http://dx.doi.org/10.1152/japplphysiol.00955.2007.
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Many epidemiological studies have demonstrated that level of exercise is associated with reduced colorectal cancer risk. Treadmill training can decrease Apc Min/+ mouse intestinal polyp number and size, but the mechanisms remain unclear. Understanding the molecular changes in the tumor following exercise training may provide insight on the mechanism by which exercise decreases Apc Min/+ mouse polyp formation and growth. The purpose of this study was to determine if exercise can modulate Apc Min/+ mouse intestinal polyp cellular signaling related to tumor formation and growth. Male Apc Min/+ mice were randomly assigned to control ( n = 20) or exercise ( n = 20) treatment groups. Exercised mice ran on a treadmill at a moderate intensity (18 m/min, 60 min, 6 days/wk, 5% grade) for 9 wk. Polyps from Apc Min/+ mice were used to quantify markers of polyp inflammation, apoptosis, and β-catenin signaling. Exercise decreased the number of macrophages in polyps by 35%. Related to apoptosis, exercise decreased the number of terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL)-positive cells by 73% in all polyps. Bax protein expression in polyps was decreased 43% by exercise. β-Catenin phosphorylation was elevated 3.3-fold in polyps from exercised mice. Moderate-intensity exercise training alters cellular pathways in Apc Min/+ mouse polyps, and these changes may be related to the exercise-induced reduction in polyp formation and growth.
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Yariktas, Murat, Fehmi Doner, Recep Sutcu, Mustafa Demirci, Harun Dogru, and Hasan Yasan. "The Effect of Topical Corticosteroid on Basic Fibroblast Growth Factor in Nasal Polyp Tissue." American Journal of Rhinology 19, no. 3 (May 2005): 248–50. http://dx.doi.org/10.1177/194589240501900306.
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Background The etiology of nasal polyposis and pathophysiological mechanisms of polyp formation is still poorly understood. Experimental models have suggested that nasal polyp growth requires extracellular matrix formation and is associated with fibroblast proliferation. Intranasal corticosteroids appear to be useful in reducing nasal polypoid lesions and the likelihood of polyp recurrence after surgery. Basic fibroblast growth factor (bFGF) is a potent angiogenesis factor and is mitogenic for a wide range of cell types. We investigated the alteration of bFGF levels in nasal polyp tissue after administration of topical corticosteroid. Methods Nasal polyp tissues were obtained from 36 patients with diffuse nasal polyposis before and after topical nasal steroid treatment. As a topical nasal steroid mometasone furoate was given for 4 weeks in a dosage of 200 μg/day. The bFGF levels were measured by competitive enzyme immunoassay method. Results The mean levels of tissue bFGF, before and after topical nasal steroid treatment, were 1485 ± 826 ng/mg protein (range, 416–3434 ng/mg) and 1340 ± 749 ng/mg protein (range, 330–3288 ng/mg), respectively. The levels of bFGF in nasal polyps were significantly lower than those before treatment after administration of topical nasal steroid (p = 0.011). Conclusion Administration of topical nasal steroid decreases bFGF levels of nasal polyp. It may be suggested that one of the effects in diminishing the size of nasal polyps is by decreasing the bFGF.
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Borst, Marilyn J., and David A. Margolin. "Polyp Growth and Polyp-Cancer Sequence." Clinics in Colon and Rectal Surgery 15, no. 2 (2002): 097–104. http://dx.doi.org/10.1055/s-2002-32057.
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Powers, Michael R., Janice M. Liebler, Zhenhong Qu, Michael A. Wall, Philip C. Lagesse, and James T. Rosenbaum. "Expression of Basic Fibroblast Growth Factor in Nasal Polyps." Annals of Otology, Rhinology & Laryngology 107, no. 10 (October 1998): 891–97. http://dx.doi.org/10.1177/000348949810701014.
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Basic fibroblast growth factor (bFGF) is a polypeptide that is mitogenic for a wide variety of cell types. We used Northern blot analysis and immunohistochemistry to determine if bFGF is expressed in the nasal polyp tissue; bFGF messenger RNA was detectable in the polyps examined by Northern blot analysis. Strong immunostaining for bFGF was found in blood vessels and along the basement membrane of the epithelial cell layers. Basal epithelial cells and some infiltrating mononuclear cells also stained for bFGF. Proliferating cell nuclear antigen colocalized with bFGF to basal epithelial cells, endothelial cells, and areas of focal epithelial metaplasia. The polyp tissue was double-labeled with a mouse monoclonal antitryptase, a specific mast cell marker, and anti-bFGF. A significant number (65% ± 19%) of the bFGF-positive mononuclear cells in the polyp tissues were positive for tryptase. These findings suggest that bFGF may contribute to the endothelial and epithelial proliferation in nasal polyp tissues and that mast cells are one source of this growth factor.
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Blackstone, Neil W. "Redox state, reactive oxygen species and adaptive growth in colonial hydroids." Journal of Experimental Biology 204, no. 11 (June 1, 2001): 1845–53. http://dx.doi.org/10.1242/jeb.204.11.1845.
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SUMMARYColonial metazoans often encrust surfaces over which the food supply varies in time or space. In such an environment, adaptive colony development entails adjusting the timing and spacing of feeding structures and gastrovascular connections to correspond to this variable food supply. To investigate the possibility of such adaptive growth, within-colony differential feeding experiments were carried out using the hydroid Podocoryna carnea. Indeed, such colonies strongly exhibited adaptive growth, developing dense arrays of polyps (feeding structures) and gastrovascular connections in areas that were fed relative to areas that were starved, and this effect became more consistent over time. To investigate mechanisms of signaling between the food supply and colony development, measurements were taken of metabolic parameters that have been implicated in signal transduction in other systems, particularly redox state and levels of reactive oxygen species. Utilizing fluorescence microscopy of P. carnea cells in vivo, simultaneous measurements of redox state [using NAD(P)H] and hydrogen peroxide (using 2′,7′-dichlorofluorescin diacetate) were taken. Both measures focused on polyp epitheliomuscular cells, since these exhibit the greatest metabolic activity. Colonies 3–5h after feeding were relatively oxidized, with low levels of peroxide, while colonies 24h after feeding were relatively reduced, with high levels of peroxide. The functional role of polyps in feeding and generating gastrovascular flow probably produced this dichotomy. Polyps 3–5h after feeding contract maximally, and this metabolic demand probably shifts the redox state in the direction of oxidation and diminishes levels of reactive oxygen species. In contrast, 24h after feeding, polyps are quiescent, and this lack of metabolic demand probably shifts the redox state in the direction of reduction and increases levels of reactive oxygen species. Within-colony differential feeding experiments were carried out on colonies 24h after the usual, colony-wide feeding. At this time, a single polyp was fed, and this polyp was compared with an otherwise similar polyp from the same colony. A pattern similar to the whole-colony experiments was obtained: the just-fed polyp, as it begins contracting shortly after feeding, appears to be relatively oxidized, with low levels of peroxide compared with the polyp that was not fed. These data are consistent with the hypothesis that adaptive colony development in response to a variable food supply is mediated by redox state or reactive oxygen species or both, although alternative hypotheses are also discussed.
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Choe, Goun, January E. Gelera, and Jeong-Whun Kim. "Case Series of Antrovestibular Polyp: An Unusual Growth of Antral Polyp Toward the Nasal Vestibule Through the Anterior Fontanelle." Journal of Rhinology 27, no. 1 (May 31, 2020): 50–53. http://dx.doi.org/10.18787/jr.2019.00292.
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Background and Objectives: This case series is aimed to introduce a new term, antrovestibular polyp (AVP), for an antral polyp herniating anteriorly toward the nasal vestibule and to describe an antral polyp direction of growth through the anterior and posterior fontanelles.Materials and Method: This is a retrospective study involving review of patients who underwent surgery due to maxillary sinus polyp herniating anteriorly toward the nasal vestibular area or posteriorly toward the choana at a tertiary training hospital from January 2007 through July 2016. Their demographic data, computed tomography scan findings, and endoscopic evaluations were analyzed.Results: This study included 49 subjects; 8 (16.33%, 6 males) with AVP and 41 (83.67%, 24 males) with antrochoanal polyps (ACP). The mean ages of AVP and ACP patients were 9 and 14.4 years, respectively (p=0.006). The subjects were identified as AVP when computed tomography scan showed an antral polyp directed anteriorly toward the nasal vestibular area, while polyps growing toward the choana were identified as ACP. Endoscopic review showed that AVP grew out through an accessory ostium located anterior to the uncinate process at the area of the anterior fontanelle, while ACP started from an accessory ostium of the posterior fontanelle or a widened maxillary natural ostium.
Dissertations / Theses on the topic "Polyp growth"
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Stevenson, Christopher Eric, and Chris Stevenson@aihw gov au. "A microsimulation study of the benefits and costs of screening for colorectal cancer." The Australian National University. National Centre for Epidemiology and Population Health, 2001. http://thesis.anu.edu.au./public/adt-ANU20040611.162207.
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This thesis examines the benefits and costs of screening for colorectal cancer in the context of an organised population screening programme. It uses microsimulation modelling to derive an optimally cost-effective screening protocol for various combinations of the available screening tests. ¶
First a mathematical model for the natural history of colorectal cancer is derived, based on analyses of Australian population and hospital-based cancer registries combined with data from published studies. Then a model for population based screening is derived based mainly on data from published screening studies, including the four major published randomised controlled trials of faecal occult blood test (FOBT) screening. These two models are used to simulate the application of a screening programme to the Australian population. The simulations are applied to a period of 40 years following 1990 (the studys base year), with both costs and benefits discounted back to the base year at an annual rate of 3%.¶
The models are applied to simulating a population screening programme based on FOBT with a colonoscopy follow up of positive tests. This simulation suggests that the optimal application of such a programme would be to offer annual screening to people aged 50 to 84 years. Such a programme would lead to a cumulative fall in years of life lost to colorectal cancer (YLL) of 28.5% at a cost per year of life saved (YLS) of $8,987. These costs and benefits are consistent with those arising from other currently funded health interventions. They are also consistent with the cost per YLS which Australian governments appear willing to pay for health interventions when justified on the basis of cost-effectiveness. The fall in colorectal cancer deaths from this screening programme should be first detectable by a national monitoring system after around three years of screening. However the full benefits from screening would not be realised before around 30 years of screening.¶
These simulations are based on the standard guaiac FOBT, but the results suggest that significant cost-effective gains could be made by using the newer immunochemical FOBT. Further cost-effect gains could be made by offering sigmoidoscopy every five years in addition to annual FOBT.¶
The models are then applied to simulating population screening programmes using colonoscopy and sigmoidoscopy as primary screening tools. Offering colonoscopy every ten years to all people aged from 45 to 85 leads to an overall fall in cumulative YLL of 37.6%, at a cost of $15,585 per YLS. Offering sigmoidoscopy every three years to all people aged 40 to 85 leads to an overall fall in cumulative YLL of 29.1%, at a cost of $4,862 per YLS. Both of these cost and benefit results are also consistent with the cost per YLS which Australian governments appear willing to pay. The fall in deaths with colonoscopy screening would also be detectable after three years of screening but the fall with sigmoidoscopy screening would not be detectable until after six years of screening. Sigmoidoscopy would need around 35 years of screening to reach its potential gains while colonoscopy screening would not reach its full potential during the 40 year screening period.¶
Finally the models are applied to targeting people at higher risk of cancer. The results show that offering colonoscopy every five years to people at higher risk because of a family history of colorectal cancer is a cost-effective addition to the annual FOBT screening programme.¶
An earlier version of chapter two of this thesis has been published as
Stevenson CE 1995. Statistical models for cancer screening. Statistical Methods in Medical Research; 4: 1923.¶
An expanded version of chapter two, along with parts of chapter one, has been published as
Stevenson CE 1998. Models of screening. In: Encyclopedia of Biostatistics. Armitage P, Colton T, eds. John Wiley and Sons Ltd, pp 39994022.
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Bernard, Alexandre. "Polylactide Growth on Various Oxides: Towards New Materials." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1275480586.
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Marinetti, Loris. "The effect of poly(lactide)-poly(carbonate) based block copolymers on the morphology and crystallization of double crystalline poly(lactide)/poly(ε-caprolactone) blends." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/11965/.
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Block copolymers of poly(lactide) and poly(carbonate) were synthetized in three different compositions and characterized by 1H-NMR and ATR analyses. The compatibilization effect of this copolymers on 80/20 (w/w%) PLA/PCL blend was evaluated. SEM micrographs show that all the blends exhibit the typical sea-island morphology characteristic of immiscible blends with PCL finely dispersed in droplets on a PLA matrix. Upon the addiction of the copolymers a reduction on PCL droplets size is observable. At the same time, a Tg depression of the PLA phase is detected when the copolymers are added in the blend. These results indicate that these copolymers are effective as compatibilizers. The copolymer that acts as the best compatibilizer is the one characterized by the same amount of PLA and PC as repeating units. As result, in the blend containing this copolymer PLA phase exhibits the highest spherulitic growth rate. An analyses on PLA phase crystallization behaviour from the glassy state within the blends was evaluated by DSC experiments. Isothermal cold crystallization of the PLA phase is enhanced up an order of magnitude upon the blending with PCL. Annealing experiments demonstrated that the crystallization of the PCL phase induces the formation of active nuclei in PLA when cooled above cooled below Tg. When the crystallization rate of PCL is retarded, a reduction on PLA nucleation is observed.
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Kappenberger, Rhea. "Das System LaFeAsO in Poly- und Einkristallen." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2018. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-235308.
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In dieser Arbeit wurde die Ausgangsverbindung der eisenbasierten Supraleiter, LaFeAsO, durch die Synthese und Charakterisierung von poly- und einkristallinen Proben untersucht. Supraleitung kann in den eisenbasierten Supraleitern durch Elektronen- oder Lochdotierung hervorgerufen werden. Die Substitution von Eisen durch Mangan, formal eine Lochdotierung, hat hingegen einen destruktiven Effekt auf die Supraleitung. Dieser ist bei optimal fluordotiertem LaFeAs(O,F) um Größenordnungen stärker ausgeprägt als bei Nd- oder Sm-FeAs(O,F). Indem Lanthan partiell durch das kleinere Yttrium substituiert wurde, konnte gezeigt werden, dass diese unterschiedlich starke Mangantoleranz durch die Unterschiede im Seltenerdmetall-Ionenradius bedingt ist. Weiterhin finden sich Anzeichen, dass die Unterdrückung der Supraleitung durch Mangan mit Elektronenlokalisierung korreliert ist.
Das Fehlen von großen dreidimensionalen Einkristallen der SEFeAsO-Verbindungsklasse stellt ein großes Hindernis in der Erforschung der elektronischen Eigenschaften der eisenbasierten Supraleiter dar. Im Rahmen dieser Arbeit konnte gezeigt werden, dass das Verfahren der Festkörper-Einkristallzüchtung ein geeignetes Mittel darstellt, um große, facettierte SEFeAsO-Einkristalle mit ausgeprägtem Wachstum in c-Richtung zu erhalten.
Mit diesem neu entwickelten Einkristallzüchtungsverfahren konnte ein aktualisiertes Phasendiagramm von La(Fe,Co)AsO erstellt werden. Die Substitution von Eisen durch Cobalt entspricht einer Elektronendotierung und führt zu Supraleitung mit einer maximalen Sprungtemperatur von 12 K. Die Ausgangsverbindung LaFeAsO zeigt bei etwa 156 K einen strukturellen Phasenübergang von einer tetragonalen zu einer orthorhombischen Struktur, weiterhin tritt unterhalb von etwa 138 K eine Spindichtewelle auf. In Einklang mit dem bekannten Phasendiagramm werden mit Cobaltdotierung die beiden Übergänge unterdrückt, mit höheren Cobaltkonzentrationen kommt es zu Supraleitung.
Anders als beim bekannten Phasendiagramm kann eine deutliche Aufspaltung zwischen magnetischem und strukturellen Übergang bei kleinen Cobaltkonzentrationen beobachtet werden. Außerdem findet sich eine Region der Koexistenz zwischen Supraleitung und Spindichtewelle. Bisher konnte ein solcher Zustand im SE(Fe,Co)AsO-System nicht beobachtet werden.
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Rincón-Rosenbaum, Charlene. "Development of poly(3-octylthiophene) thin films for regulating osteoblast growth." Diss., Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/26493.
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The overall objective of this work was to assess the suitability of poly(3-octylthiophene) (P3OT) to sustain MC3T3-E1 osteoblast attachment and growth. The central hypothesis was that specific P3OT film properties (i.e., thickness, film preparation conditions, and level of doping) are able to regulate osteoblast functions (i.e., attachment and proliferation). Discrete and combinatorial techniques were utilized to prepare and characterize thin films of P3OT, a semiconductor in its undoped state, and to study its interaction with MC3T3-E1 osteoblasts.
In this work we demonstrate that P3OT is a suitable surface to sustain MC3T3-E1 attachment and proliferation with no observed cytotoxicity. We show that P3OT has an effect on MC3T3-E1 attachment and proliferation as area, circularity, and proliferation ratio are significantly different for P3OT compared to control surfaces. We also demonstrate that P3OT doping and film preparation conditions have an effect on osteoblast attachment and proliferation but that thickness over a low and high range does not affect osteoblast functions.
This work is significant because it contributes to the growing area of conducting polymers in biomedical applications and establishes P3OT as a potential cell substrate that sustains MC3T3-E1 attachment and promotes high levels of cell proliferation.
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Rincón-Rosenbaum, Charlene. "Development of poly(3-octylthiophene) thin films for regulating osteoblast growth." Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/26493.
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Thesis (Ph.D)--Chemical Engineering, Georgia Institute of Technology, 2009.Committee Chair: J. Carson Meredith; Committee Member: Hang Lu; Committee Member: Joseph Schork; Committee Member: William Koros; Committee Member: Yadong Wang. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Hrabálková, Lenka. "The importance of poly(A)-binding protein 4 (PABP4) in healthy pregnancy." Thesis, University of Edinburgh, 2016. http://hdl.handle.net/1842/22923.
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Healthy pregnancy requires a tightly regulated materno-fetal dialogue for processes such as embryo implantation, endometrial decidualisation (in the mouse), placentation and maternal adaptation to occur. Disruption of placental development as well as maternal adaptation can lead to fetal intrauterine growth restriction (IUGR) which increases the risk of late miscarriage/stillbirth (e.g. 53% of preterm stillbirth and 26% of term stillbirth are found to be IUGR). Furthermore, IUGR is a risk factor for neurodevelopmental conditions in childhood and for a spectrum of related adult health disorders such as cardiovascular disease and type II diabetes, often termed metabolic syndrome. Despite these pregnancy disorders being common (e.g. 1 in 200 pregnancies results in stillbirth in the UK) the molecular lesion(s) underlying their pathophysiology are poorly understood and in particular those with placental and/or maternal aetiologies most frequently remain unexplained. Here we investigate the hypothesis that poly(A)-binding protein 4 (PABP4) is required for healthy pregnancy in mice. PABP4 is an RNA-binding protein and a member of the PABP family which are central regulators of mRNA translation and stability. Using all four permutations of wild-type and knock-out crosses, we find that maternal PABP4-deficiency results in a reduced litter size and IUGR. The number of implantations at e8.5 were not reduced in Pabp4-/- females, implying that the reduced litter size was not a consequence of decreased ovulation, fertilisation or implantation frequency. Further longitudinal analysis (at e13.5, e15.5 and e18.5) reveals that fetal death primarily occurred between e18.5 and birth, suggesting these mice may provide a unique opportunity to inform on the maternal causes of stillbirth. The onset of IUGR, which was found to be symmetrical in nature, was established by e15.5 preceding the majority of fetal death. During pregnancy, a materno-fetal dialogue directs and responds to changes in gene expression to give rise to the placenta and adapt the maternal physiology. Defects in these processes may result in reduced growth and/or fetal death and were examined in Pabp4-/- mice to shed light on the mechanistic basis of these related phenotypes. Fetal to placental (F:P) weight ratio, whose changes can be indicative of placental insufficiency or placental adaptation in an attempt to aid fetal growth, was found to be increased in Pabp4-/- dams at e15.5 and e18.5 due to the presence of IUGR fetuses with placentas of normal weight. Consistent with this observation, placental volume was unchanged at e18.5. Total placental weight and volume alone fails to discriminate potential differences in the individual placental zones which include the labyrinth zone, where materno-fetal gas and nutrient exchange occur; the junctional zone, which has endocrine functions including those that promote maternal adaptation; and the decidua basalis, derived from the maternal endometrium and is the site of trophoblast invasion and maternal vascular remodelling in early pregnancy. Therefore, volumetric analysis of these zones and the maternal blood spaces, which transcend the decidua basalis and junctional zone, was undertaken. This showed no change in the maternal blood spaces or the labyrinth, the latter being the zone whose size is most frequently altered in IUGR. Critically however, the size of the maternally-derived decidua basalis was increased with a concurrent decrease in the size of the junctional zone. These morphological changes may play a causative role either through directly affecting placental function and/or by the reduced junctional zone failing to promote appropriate maternal adaptation. Alternatively, they may reflect compensatory adaptations to a primary defect elsewhere in the mother. Complementing these morphological studies, functional studies were undertaken: remodelling of maternal vasculature and the resistance index of vessels delivering blood to the fetus were assessed; as was delivery of nutrients to the fetus (measured by fetal glucose); and systemic maternal adaptations (maternal hormonal profile, circulating glucose levels and organ weights). Uterine, umbilical and decidual spiral arteries were examined, but displayed no apparent differences suggestive of normal blood supply to the fetus. However fetal blood glucose was reduced suggesting a reduced delivery of nutrients important for fetal growth. This was not due to lower circulating maternal blood glucose levels, and mRNA levels of the placental glucose transporters Glut-1 and Glut-3 were not reduced but upregulated, suggestive of an attempt to compensate for reduced fetal glucose. Furthermore, upregulation of at least one system A amino acid transporter mRNA, Snat-2, was observed. The maternal physiological state of PABP4-deficient dams showed deviations in some organ weights (e.g. spleen weight is reduced at e13.5 and e15.5) and the levels of some circulating hormones (e.g. estradiol is deceased whereas progesterone is increased at e18.5). However, future work will be required to determine which, if any, of these changes are primary defects rather than downstream consequences and to identify which mis-regulated mRNAs/pathways within in the materno-fetal dialogue underlie the phenotype. Taken together, my results suggest that the regulation of mRNA translation/stability by PABP4 is critical to achieving the correct pattern of gene expression within the materno-fetal dialogue to enable appropriate placentation and maternal adaptation. Furthermore, my results suggest that Pabp4-/- mice provide a unique opportunity to further understand the maternal causes of a spectrum of related pregnancy complications including IUGR, late miscarriage and stillbirth.
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Li, Bingbing. "Phase Behavior of Poly(Caprolactone) Based Polymer Blends As Langmuir Films at the Air/Water Interface." Diss., Virginia Tech, 2007. http://hdl.handle.net/10919/26210.
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Poly (caprolactone) (PCL) has been widely studied as a model system for investigating polymer crystallization. In this thesis, PCL crystallization along with other phase transitions in PCL-based polymer blends are studied as Langmuir films at the air/water (A/W) interface.
In order to understand the phase behavior of PCL-based blends, surface pressure induced crystallization of PCL in single-component Langmuir monolayers was first studied by Brewster angle microscopy (BAM). PCL crystals observed during film compression exhibit butterfly-shapes. During expansion of the crystallized film, polymer chains detach from the crystals and diffuse back into the monolayer as the crystals â meltâ . Electron diffraction on Langmuir-Schaefer films suggests that the lamellar crystals are oriented with the chain axes perpendicular to the substrate surface, while atomic force microscopy (AFM) reveals a crystal thickness of ~ 7.6 nm. In addition, the competition between lower segmental mobility and a greater degree of undercooling with increasing molar mass produces a maximum average growth rate at intermediate molar mass.
PCL was blended with poly(t-butyl acrylate) (PtBA) to study the influence of PtBA on the morphologies of PCL crystals grown in monolayers. For PCL-rich blends, BAM studies reveal dendritic morphologies of PCL crystals. The thicknesses of the PCL dendrites are ~ 7-8 nm. BAM studies during isobaric area relaxation experiments at different surface pressure reveal morphological transitions from highly branched dendrites, to six-arm dendrites, four-arm dendrites, seaweedlike crystals, and distorted rectangular crystals. In contrast, PCL crystallization is suppressed in PtBA-rich blend films.
For immiscible blends of PCL and polystyrene (PS) with intermediate molar masses as Langmuir films, the surface concentration of PCL is the only factor influencing surface pressure below the collapse transition. For PS-rich blends, both BAM and AFM studies reveal that PS nanoparticle aggregates formed at very low surface pressure form networks during film compression. For PCL-rich blends, small PS aggregates serve as heterogeneous nucleation centers for the growth of PCL crystals. During film expansion, BAM images show a gradual change in the surface morphology from highly continuous networklike structures (PS-rich blends) to broken ringlike structures (intermediate composition) to small discontinuous aggregates (PCL-rich blends).Ph. D.
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Merrett, Kim. "Interactions of corneal cells with transforming growth factor-beta modified poly(dimethyl siloxane) surfaces." Thesis, University of Ottawa (Canada), 2002. http://hdl.handle.net/10393/6410.
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Although the growth of native corneal epithelial cells over the anterior surface of an artificial corneal implant is desired, the growth of these cells on the interface located between the implant and the stromal layer of the host eye tissue (i.e. epithelial cell downgrowth) poses a significant problem to be overcome in developing a suitable implant. In this study the growth factor surface modification of a polymer substrate was examined as a means of inhibiting the proliferation of corneal epithelial cells while promoting corneal stromal cell growth. Two separate studies were conducted in which transforming growth factor-beta1 (TGF-beta1) and transforming growth factor-beta2 (TGF-beta2) respectively, were immobilized via a bifunctional poly (ethylene glycol) (PEG) spacer, MW 3400, to poly(dimethyl siloxane) surfaces (PDMS) that had been aminated by the plasma polymerization of allylamine. The modified surfaces were chemically and biologically characterized. The effect of the surface modification with TGF-beta1 and TGF-beta2 respectively, on interactions with corneal epithelial and corneal stromal cells was examined using in vitro cell culture. (Abstract shortened by UMI.)
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Kennedy, Mary A. "Crystallization and melting behavior studies of un-nucleated and silica-nucleated isotactic polystyrene and isotactic poly(propylene oxide)." Thesis, McGill University, 1988. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=75765.
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The effect of silica on the crystallization and melting behavior of a highly isotactic, well characterized isotactic polystyrene (i-PS) have been investigated. The origins of the various endotherms obtained upon heating have been defined by partial scanning experiments and by a study of the effect of heating rate using differential scanning calorimetry (DSC). The presence of 1 part silica in 100 parts polymer (1 pph) decreases the maximum degree of crystallinity considerably but has a minimal effect on the rate of crystallization. Analysis by the Avrami method shows that the silica does not affect the overall rate of crystallization significantly. The decrease in the crystallinity indicates that silica affects the level of secondary crystallization, thus the crystal perfection.The surface morphologies and growth rates of i-PS spherulites, as studied by photomicroscopy, were not affected by 1 pph of silica. The experimental data were fitted to a modified form of the Hoffman-Lauritzen equation.
The effect of silica on spherulite growth rates and surface morphologies of isotactic poly(propylene oxide) (i-PPO) have also been investigated by optical microscopy. Two distinct i-PPO samples of different molecular weights were used, each of which was highly isotactic. The addition of silica has a pronounced effect on the morphology of the spherulites, producing dendritic type morphology. Upon step-crystallization, the spherulites exhibited mixed morphologies, i.e., fibrillar and ringed. Silica depresses the spherulite growth rates throughout the entire temperature range. The effects were more profound as the quantity of filler increased. The growth rate-temperature behavior was analysed in terms of the classical Hoffman-Lauritzen equation and a modified version to take into account the polymer-filler interaction.
Books on the topic "Polyp growth"
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Mwaluma, James. Culture experiment on the growth and production of mud crabs, mullets, milkfish and prawns in Mtwapa mangrove system, Kenya. [Zanzibar]: WIOMSA, 2003.
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Snell, Jamey, and Thomas J. Mancuso. Cystic Fibrosis. Edited by Kirk Lalwani, Ira Todd Cohen, Ellen Y. Choi, and Vidya T. Raman. Oxford University Press, 2018. http://dx.doi.org/10.1093/med/9780190685157.003.0023.
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Cystic fibrosis (CF) is an inherited, autosomal recessive, multisystem disease. Dysfunction of the cystic fibrosis transmembrane conductance regulator protein (CFTR) in epithelial cells is the primary defect in CF. Defects in CFTR are the cause for lung disease, exocrine pancreatic insufficiency and failure, male infertility, and liver disease. CF can present with a variety of respiratory and gastrointestinal signs, including meconium ileus in the newborn period, hypernatremic dehydration, pulmonary insufficiency, nasal polyps, and insulin-dependent diabetes mellitus. As affected children grow, dysfunction in CFTR leads to chronic and progressive lung disease, characterized by suppurative infection and the development of bronchiectasis. CFTR dysfunction also affects exocrine function, leading to pancreatic insufficiency, malabsorption, and growth failure. In the past, history and physical exam with sweat chloride testing were the cornerstones of diagnosis. Diagnosis is now made with the newborn screening test for immunoreactive trypsinogen.
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Theologis, Tim. Musculoskeletal injuries in children. Oxford University Press, 2011. http://dx.doi.org/10.1093/med/9780199550647.003.014001.
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♦ In children, bone is more flexible and heals faster than in adults but is at risk of growth disturbance. It is also capable of remodelling♦ The physis is weaker than the structures around it and therefore is liable to disruption in trauma♦ The possibility of injuries as a result of abuse must be considered in children and have a characteristic pattern♦ In poly trauma, children are more susceptible to hypothermia. Abdominal viscera and the cranium are more vulnerable. However, the central nervous system has more scope for recovery, and the cardiovascular system has an excellent capacity for coping with hypovolaemic shock♦ A reliable specific paediatric score should be used to plan treatment♦ The management of fractures is more likely to involve traction, plaster, and K-wires.
Book chapters on the topic "Polyp growth"
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Merks, Roeland, Alfons Hoekstra, Jaap Kaandorp, and Peter Sloot. "Spontaneous Branching in a Polyp Oriented Model of Stony Coral Growth." In Lecture Notes in Computer Science, 88–96. Berlin, Heidelberg: Springer Berlin Heidelberg, 2002. http://dx.doi.org/10.1007/3-540-46043-8_8.
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Labadie, Jeff W., James L. Hedrick, and Mitsuru Ueda. "Poly(aryl ether) Synthesis." In Step-Growth Polymers for High-Performance Materials, 210–25. Washington, DC: American Chemical Society, 1996. http://dx.doi.org/10.1021/bk-1996-0624.ch012.
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Matray, T. J., R. J. Twieg, and James L. Hedrick. "Poly(aryl ether benzazole)s." In Step-Growth Polymers for High-Performance Materials, 266–75. Washington, DC: American Chemical Society, 1996. http://dx.doi.org/10.1021/bk-1996-0624.ch016.
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Wang, Sheng, and J. E. McGrath. "Synthesis of Poly(Arylene Ether)s." In Synthetic Methods in Step-Growth Polymers, 327–74. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2003. http://dx.doi.org/10.1002/0471220523.ch6.
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Yamamoto, Kimihisa, and Eishun Tsuchida. "Poly(sulfonium cation) for the Synthesis of High-Molecular-Weight Poly(phenylene sulfide)." In Step-Growth Polymers for High-Performance Materials, 377–90. Washington, DC: American Chemical Society, 1996. http://dx.doi.org/10.1021/bk-1996-0624.ch024.
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Hay, Allan S. "Synthesis of Novel Poly(aryl ether)s." In Step-Growth Polymers for High-Performance Materials, 239–49. Washington, DC: American Chemical Society, 1996. http://dx.doi.org/10.1021/bk-1996-0624.ch014.
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Androsch, René, Christoph Schick, and Maria Laura Di Lorenzo. "Kinetics of Nucleation and Growth of Crystals of Poly(l-lactic acid)." In Synthesis, Structure and Properties of Poly(lactic acid), 235–72. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/12_2016_13.
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Marquardt, L. M., R. A. Scott, and R. K. Willits. "Neurite Growth in Protein-Conjugated Poly(Ethylene Glycol) Hydrogels." In IFMBE Proceedings, 173–74. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-642-01697-4_63.
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Carter, Kenneth R. "Investigation of Monomer Reactivity in Poly(aryl ether) Synthesis Utilizing19F NMR Spectroscopy." In Step-Growth Polymers for High-Performance Materials, 276–91. Washington, DC: American Chemical Society, 1996. http://dx.doi.org/10.1021/bk-1996-0624.ch017.
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Huang, J., A. Prasad, and H. Marand. "Analysis of the Spherulitic Growth Rate of Poly(Pivalolactone) in Blends with Poly(Vinylidene Fluoride)." In Crystallization of Polymers, 581–86. Dordrecht: Springer Netherlands, 1993. http://dx.doi.org/10.1007/978-94-011-1950-4_60.
Full textConference papers on the topic "Polyp growth"
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Walker, Ebonee A., Roberto Aga, and Richard Mu. "Low Temperature Growth of ZnO Nanowires for Hybrid Chemical Sensors." In ASME 2007 International Mechanical Engineering Congress and Exposition. ASMEDC, 2007. http://dx.doi.org/10.1115/imece2007-41480.
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Hybrid nanocomposites, such as ZnO nanowires embedded in conducting polymers, are very attractive for chemical sensing applications. Previous studies have shown that tuning ZnO nanowire concentration with respect to the polymer can be employed to tailor chemical sensitivity and selectivity. In this work, we investigate the effect of ZnO nanowire growth time on the electrical transport properties of sensors with and without the polymer matrix. Varying growth times may affect wire lengths, wire concentration, as well as wire interconnectivity. Using pure Zn as the source, ZnO nanowires are grown on a glass substrate by a low temperature thermal evaporation method. Poly(3-hexylthiophene) is employed as the polymeric matrix to form a hybrid structure. The response to ethanol vapor of sensors with different nanowire growth times is evaluated.
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Evrensel, Cahit A., Lisbeth A. Welniak, Alan Fuchs, Jigar Patel, William J. Murphy, and Faramarz Gordaninejad. "Utilization of Biocompatible Ferrous Particles for a New Cancer Therapy." In ASME 2009 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2009. http://dx.doi.org/10.1115/sbc2009-206803.
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Magneto-rheologiacal Fluid (MRF), suspensions of polarizable micron size particles, is synthesized from suspensions of iron particles (micron and nano size) in phosphate buffered saline (PBS). The iron particles have been surface coated using atom transfer radical polymerization (ATRP) with various polymers, such as poly(N-isopropylacrylamide) (poly(NIPAAm)), and poly(acrylamide) (poly(AAm)). The surface grafted polymer has been characterized using differential scanning calorimetry (DSC), and properties of resulting fluid have been measured using a rheometer. A mathematical model is developed to explore the force induced by the particles on the neighboring tissue under externally applied magnetic field. This force results in the damage of the tumor cell lines and trigger the immune system response. The effect of MRF on primary and metastasized tumor growth were evaluated by using an orthotopic murine breast cancer model (4T1). Tumors were evaluated by growth measurements and histological changes following injection of MRF or carrier fluid alone into the tumor and the effects of subsequent application of a magnetic field to the site. Results indicate slowed tumor growth and increased dendritic cell activation with this therapy and they are encouraging.
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Gao, Bo, Xin-Ping He, Hui Suo, and Chun Zhao. "Direct Growth of Poly(3,4-ethylenedioxythiophene) on Carbon Cloth for Supercapacitor." In 2014 International Conference on Mechatronics, Electronic, Industrial and Control Engineering. Paris, France: Atlantis Press, 2014. http://dx.doi.org/10.2991/meic-14.2014.180.
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Ikejiri, K., K. Tomioka, S. Imai, and T. Fukui. "Growth of GaAs Nanowires on Poly-Si by Selective-Area MOVPE." In 2011 International Conference on Solid State Devices and Materials. The Japan Society of Applied Physics, 2011. http://dx.doi.org/10.7567/ssdm.2011.p-13-4.
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Castro, Nathan J., Christopher O’Brien, and Lijie Grace Zhang. "Development of Biomimetic and Bioactive 3D Nanocomposite Scaffolds for Osteochondral Regeneration." In ASME 2013 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/imece2013-66107.
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Osteochondral tissue is composed of ordered and random biological nanostructures and can, in principal, be classified as a nanocomposite material. Thus, the objective of this research is to develop a novel biomimetic biphasic nanocomposite scaffold via a series of 3D fabricating techniques for osteochondral tissue regeneration. For this purpose, a highly porous Poly(caprolactone) (PCL) bone layer with bone morphogenetic protein-2 (BMP-2)-encapsulated Poly(dioxanone) (PDO) nanospheres and nanocrystalline hydroxyapatite was photocrosslinked to a Poly(ethylene glycol)-diacrylate (PEG-DA) cartilage layer containing transforming growth factor-β1 (TGF-β1)-encapsulated PLGA nanospheres. Novel tissue-specific growth factor-encapsulated nanospheres were efficiently fabricated via a wet co-axial electrospraying technique. Integration and porosity of the distinct layers was achieved via co-porogen leaching and ultraviolet (UV) photocrosslinking of water soluble poly(ethylene glycol) (PEG) and <150 um sodium chloride salt particles providing greater control over pore size and increased surface area. Our in vitro results showed significantly improved human bone marrow derived mesenchymal stem cells (hMSCs) adhesion and differentiation in bone and cartilage layers, respectively. In addition, we are working on developing a novel table top stereolithography (SL) apparatus for the manufacture of custom designed 3D biomimetic scaffolds with incorporated growth factor encapsulated nanospheres for osteochondral defect repair. Our early-stage SL development has illustrated good corroboration between computer-aided design (CAD) and manufactured constructs with controlled geometry. The ultimate goal of the novel tabletop SL system is the manufacture of patient-specific implantable 3D nanocomposite scaffolds for osteochondral defect repair. The current SL system developed in our lab allows for efficient photocrosslinking of two novel nanocomposite polymeric materials for the manufacture of three-dimensional (3D) osteochondral constructs with good spatiotemporal control of growth factor release in addition to exhibiting similar mechanical properties to that of the native tissues being addressed.
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Mikhailouskaya, N. A., D. V. Voitka, and E. K. Yuzefovitch. "Microbial composition with the properties of plant growth promoter, biofertilizer and biological fungicide." In 2nd International Scientific Conference "Plants and Microbes: the Future of Biotechnology". PLAMIC2020 Organizing committee, 2020. http://dx.doi.org/10.28983/plamic2020.170.
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Microbial composition A. brasilеnse+B. circulans+Т. longibrachiatum (MC) is effective inoculant for grain crops growing in erosion agrolandscaps. MC reveals the properties of plant growth promoter, biological fertilizer and biological fungicide. Poly functional positive action of three-component MC resulted in the increase of grain crops yield and improvement of its quality in stress conditions in erosion agrolandscaps.
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Banait, Arya, Vivek Vishwakarma, Leila Choobineh, and Ankur Jain. "Growth of Patterned Micropores in Poly-Dimethylsiloxane (PDMS) Using the Thermocapillary Effect." In ASME 2013 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/imece2013-65865.
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Poly-dimethylsiloxane (PDMS) is a well-known soft polymer with applications in a wide variety of research fields. PDMS is a particularly attractive material for miniaturized bioanalytical systems because of its biocompatibility, gas permeability, chemical inertness and the ability to reproduce miniature features such as microchannels in PDMS. This paper describes a technique to obtain through-membrane pores in thin PDMS membranes. This is based on thermocapillary effect in a MEMS-based microheater device made on a glass substrate. Uncured PDMS is poured on a microheater device that has been coated with a hydrophilic substrate such as poly-ethylene oxide (PEO). Upon heating, PEO evaporates and form gas bubbles in PDMS. The gas bubbles are attracted towards the hot region of the microheater device. The bubbles eventually self-assemble along the hottest isotherm, which in this case is the microheater line. In this manner, self-assembled pores in the desired pattern are obtained. Experiments conducted at different temperatures and PDMS thicknesses throw light on the physical phenomena behind this process and demonstrate the trade-off between PDMS curing rate and bubble escape rate. Results presented in this work are expected to aid in the design of novel PDMS-based membranes for filtration, separation and concentration.
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Welch, Michael. "Poly-Generation Using Biogas From Agricultural Wastes." In ASME 2019 Power Conference. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/power2019-1822.
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Abstract Across the world, many people, especially in rural communities, still lack access to secure, affordable electricity supplies. Many countries also lack or have under-developed indigenous fossil fuel resources, or rely on environmentally unfriendly fuels such as coal or Heavy Fuel Oil. Many under-developed regions though are blessed with considerable agricultural resources, and well-suited to Distributed Power Generation, where smaller decentralized power plants are located close to the actual energy consumers. Distributed Power eliminates the need for an electricity transmission grid, or reduces the investment costs necessary to strengthen the grid system, and helps ensure stable, secure electricity to support local economic growth. Agricultural wastes can be used as a locally available feedstock to produce the energy required to electrify regions and stimulate economic growth. This paper examines the benefits of applying Poly-generation — the production of multiple products at a single location — and examines a proposed bio-refinery scheme to produce ethanol from agricultural waste. The ethanol production process produces a waste biogas, which can then be used in a high efficiency Cogeneration (or Combined Heat and Power) plant as a fuel for gas turbines to generate electricity and steam (heat), not just for the bio-refinery but also local industry and businesses. By creating a high value product (ethanol) along with a free fuel, the bio-refinery acts as an anchor plant to provide reliable, affordable electricity to the local community. As well as providing economic benefits, such a concept has multiple environmental benefits as regions and nations try to combine growth in energy demand with reduction in global greenhouse gas emissions: agricultural residues that would otherwise have decayed emitting methane and CO2 into the atmosphere are used to create a high value product in ethanol, while using the biogas as a fuel displaces combustion of fossil fuels, reducing both combustion emissions and those associated with transportation of the fuel to the point of use.
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Lim, Heejin, and SangJun Moon. "Parylene coated poly(dimethylsiloxane) microfluidic channel for nonpolar solvent based nanocrystals growth." In 2013 International Conference on Manipulation, Manufacturing and Measurement on the Nanoscale (3M-NANO). IEEE, 2013. http://dx.doi.org/10.1109/3m-nano.2013.6737453.
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Mieno, F., A. Shimizu, S. Nakamura, T. Deguchi, N. Haga, I. Matsumoto, Y. Furumura, et al. "Novel selective poly - and epitaxial - Silicon growth (SPEG) technique for ULSI processing." In 1987 International Electron Devices Meeting. IRE, 1987. http://dx.doi.org/10.1109/iedm.1987.191336.
Full textReports on the topic "Polyp growth"
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Gupta, Aditya, Tong Wang, Shruthi Ravi, Mesbah Talukder, Jessie Carviel, and Mary Bamimore. Relative efficacy of microneedling in the treatment of pattern hair loss: a protocol for a systematic review with network meta-analysis. INPLASY - International Platform of Registered Systematic Review and Meta-analysis Protocols, September 2022. http://dx.doi.org/10.37766/inplasy2022.9.0042.
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Review question / Objective: The objective of the proposed study is to determine the relative efficacy of microneedling and combination of it and other agents for androgenetic alopecia (AGA)—a condition that is also referred to as pattern hair loss. Rationale: Pattern hair loss is one of the most common forms of hair loss in men and women; the condition is associated with decreased quality of life. Oral finasteride and topical minoxidil are treatments currently approved, by the United States Food and Drug Administration, for AGA. However, finasteride has been associated with significant side effects in men, and is not appropriate for women of childbearing potential. Furthermore, topical minoxidil requires daily prolonged use which is time-consuming for patients and requires high compliance to maintain efficacy. Due to these drawbacks, new treatments, such as microneedling, have been investigated. Microneedling involves the creation of small wounds on the scalp that prompt growth factor release and neovascularization—which, in turn, may promote hair growth. Microneedling has been used as a monotherapy—or in combination with other standard therapies—for the treatment of AGA. Further investigation through meta-analysis is salient as this quantitative technique can estimate the relative success of mono- and poly-therapy with microneedling; therefore, findings from a systematic review and meta-analysis on the comparative effectiveness can enable clinicians, patients, and researchers to make more informed decisions.
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Christopher, David A., and Avihai Danon. Plant Adaptation to Light Stress: Genetic Regulatory Mechanisms. United States Department of Agriculture, May 2004. http://dx.doi.org/10.32747/2004.7586534.bard.
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Original Objectives: 1. Purify and biochemically characterize RB60 orthologs in higher plant chloroplasts; 2. Clone the gene(s) encoding plant RB60 orthologs and determine their structure and expression; 3. Manipulate the expression of RB60; 4. Assay the effects of altered RB60 expression on thylakoid biogenesis and photosynthetic function in plants exposed to different light conditions. In addition, we also examined the gene structure and expression of RB60 orthologs in the non-vascular plant, Physcomitrella patens and cloned the poly(A)-binding protein orthologue (43 kDa RB47-like protein). This protein is believed to a partner that interacts with RB60 to bind to the psbA5' UTR. Thus, to obtain a comprehensive view of RB60 function requires analysis of its biochemical partners such as RB43. Background & Achievements: High levels of sunlight reduce photosynthesis in plants by damaging the photo system II reaction center (PSII) subunits, such as D1 (encoded by the chloroplast tpsbAgene). When the rate of D1 synthesis is less than the rate of photo damage, photo inhibition occurs and plant growth is decreased. Plants use light-activated translation and enhanced psbAmRNA stability to maintain D1 synthesis and replace the photo damaged 01. Despite the importance to photosynthetic capacity, these mechanisms are poorly understood in plants. One intriguing model derived from the algal chloroplast system, Chlamydomonas, implicates the role of three proteins (RB60, RB47, RB38) that bind to the psbAmRNA 5' untranslated leader (5' UTR) in the light to activate translation or enhance mRNA stability. RB60 is the key enzyme, protein D1sulfide isomerase (Pill), that regulates the psbA-RN :Binding proteins (RB's) by way of light-mediated redox potentials generated by the photosystems. However, proteins with these functions have not been described from higher plants. We provided compelling evidence for the existence of RB60, RB47 and RB38 orthologs in the vascular plant, Arabidopsis. Using gel mobility shift, Rnase protection and UV-crosslinking assays, we have shown that a dithiol redox mechanism which resembles a Pill (RB60) activity regulates the interaction of 43- and 30-kDa proteins with a thermolabile stem-loop in the 5' UTR of the psbAmRNA from Arabidopsis. We discovered, in Arabidopsis, the PD1 gene family consists of II members that differ in polypeptide length from 361 to 566 amino acids, presence of signal peptides, KDEL motifs, and the number and positions of thioredoxin domains. PD1's catalyze the reversible formation an disomerization of disulfide bonds necessary for the proper folding, assembly, activity, and secretion of numerous enzymes and structural proteins. PD1's have also evolved novel cellular redox functions, as single enzymes and as subunits of protein complexes in organelles. We provide evidence that at least one Pill is localized to the chloroplast. We have used PDI-specific polyclonal and monoclonal antisera to characterize the PD1 (55 kDa) in the chloroplast that is unevenly distributed between the stroma and pellet (containing membranes, DNA, polysomes, starch), being three-fold more abundant in the pellet phase. PD1-55 levels increase with light intensity and it assembles into a high molecular weight complex of ~230 kDa as determined on native blue gels. In vitro translation of all 11 different Pill's followed by microsomal membrane processing reactions were used to differentiate among PD1's localized in the endoplasmic reticulum or other organelles. These results will provide.1e insights into redox regulatory mechanisms involved in adaptation of the photosynthetic apparatus to light stress. Elucidating the genetic mechanisms and factors regulating chloroplast photosynthetic genes is important for developing strategies to improve photosynthetic efficiency, crop productivity and adaptation to high light environments.