Thèses : « Eye Rats »

1

Nikitina, Natalya. « African mole rats as models for regressive evolution of the eye ». Doctoral thesis, University of Cape Town, 2006. http://hdl.handle.net/11427/3187.

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Includes bibliographical references (leaves 152-166).
Darkness-adapted mammals with reduced eyes can serve as valuable models for the study of regressive evolution, as well as for research into the genetic and developmental processes underlying the "degeneration" of the eye. The aim of this work was to characterize two African mole rate species (Heterocephalus glaber and Bathyergus suillus) and explore their potential use as novel models for evolutionary developmental eye research. To this end, this histological structure of the adult eye, the development of the eye and the expression of several molecular markers were investigated. The important abnormal features noted were: the abnormal shape and nuclear distribution in the lens, the extremely large ciliary body and delay in the formation of the anterior chamber compared to other ocular structures.

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Brown, Kevin L. « The ontogeny of dual-interstimulus interval eyeblink classical conditioning in a rat model of fetal alcohol spectrum disorders ». Access to citation, abstract and download form provided by ProQuest Information and Learning Company ; downloadable PDF file, 254 p, 2008. http://proquest.umi.com/pqdweb?did=1605135131&sid=7&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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3

Mayo, Paul Raymond II. « Topically applied leptin accumulates in the eye and hypothalamus but does not influence food intake in rats / ». Adobe Acrobat Reader required to view document, 2008. http://necolib.neco.edu/library/theses/MayoThesisMay08.pdf.

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4

Goldberg, Julie R. « Eye-opening dependent elaboration and refinement of the cortical projection to the superficial superior colliculus in rats ». Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/46664.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Brain and Cognitive Sciences, February 2009.
Includes bibliographical references.
The superior colliculus (SC) is a multi-layered midbrain structure responsible for multimodal integration and orienting behavior in mammals. The superficial layers of the SC (sSC) receive direct visual input from retinal ganglion cells (RGC) as well as input from pyramidal cells in layer V of the ipsilateral visual cortex (VC). The retinal input is refined well before eye opening (EO) and RGC axons arborize topographically to form an appropriate map of visual space. The projection from VC is still broad and unrefined at the time of EO, however. In both sSC and VC, physiological and biochemical evidence indicate considerable synaptic refinement in response to EO, which occurs naturally at the end of the second postnatal week. These studies use anterograde filling of corticocollicular axons in combination with controlled eyelid opening and reclosing paradigms to compare the corticocollicular projections of age-matched eye-opened and eye-sutured littermates. Reconstructions of individual corticocollicular axons in rat pups and statistically sampled arborization patterns across the colliculus at set times before and after controlled eye-lid opening, show that the onset of pattern vision is critical for the establishment of registration between the cortical and collicular maps of visual space. Moreover, if pattern vision is delayed by prolonging eye-lid closure the cortical projection withdraws to single axon cylinders. A latent plasticity remains, however; the corticocollicular axons can reestablish topologically appropriate arborization if eye opening occurs within at least a week of its normal occurrence.
by Julie R. Goldberg.
Ph.D.

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Berteotti, Chiara <1979&gt. « Central autonomic control in spontaneously hypertensive rats : a study on phasic phenomena during rapid-eye-movement sleep ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2007. http://amsdottorato.unibo.it/495/.

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The cardiovascular regulation undergoes wide changes in the different states of sleepwake cycle. In particular, the relationship between spontaneous fluctuations in heart period and arterial pressure clearly shows differences between the two sleep states. In non rapid-eye-movement sleep, heart rhythm is under prevalent baroreflex control, whereas in rapid-eye-movement sleep central autonomic commands prevail (Zoccoli et al., 2001). Moreover, during rapid-eye-movement sleep the cardiovascular variables show wide fluctuations around their mean value. In particular, during rapid-eyemovement sleep, the arterial pressure shows phasic hypertensive events which are superimposed upon the tonic level of arterial pressure. These phasic increases in arterial pressure are accompanied by an increase in heart rate (Sei & Morita, 1996; Silvani et al., 2005). Thus, rapid-eye-movement sleep may represent an “autonomic stress test” for the cardiovascular system, able to unmask pathological patterns of cardiovascular regulation (Verrier et al. 2005), but this hypothesis has never been tested experimentally. The aim of this study was to investigate whether rapid-eye-movement sleep may reveal derangements in central autonomic cardiovascular control in an experimental model of essential hypertension. The study was performed in Spontaneously Hypertensive Rats, which represent the most widely used model of essential hypertension, and allow full control of genetic and environmental confounding factors. In particular, we analyzed the cardiovascular, electroencephalogram, and electromyogram changes associated with phasic hypertensive events during rapid-eyemovement sleep in Spontaneously Hypertensive Rats and in their genetic Wistar Kyoto control strain. Moreover, we studied also a group of Spontaneously Hypertensive Rats made phenotypically normotensive by means of a chronic treatment with an angiotensin converting enzyme inhibitor, the Enalapril maleate, from the age of four weeks to the end of the experiment. All rats were implanted with electrodes for electroencephalographic and electromyographic recordings and with an arterial catheter for arterial pressure measurement. After six days for postoperative recovery, the rats were studied for five days, at an age of ten weeks.The study indicated that the peak of mean arterial pressure increase during the phasic hypertensive events in rapid-eye-movement sleep did not differ significantly between Spontaneously Hypertensive Rats and Wistar Kyoto rats, while on the other hand Spontaneously Hypertensive Rats showed a reduced increase in the frequency of theta rhythm and a reduced tachicardia with respect to Wistar Kyoto rats. The same pattern of changes in mean arterial pressure, heart period, and theta frequency was observed between Spontaneously Hypertensive Rats and Spontaneously Hypertensive Rats treated with Enalapril maleate. Spontaneously Hypertensive Rats do not differ from Wistar Kyoto rats only in terms of arterial hypertension, but also due to multiple unknown genetic differences. Spontaneously Hypertensive Rats were developed by selective breeding of Wistar Kyoto rats based only on the level of arterial pressure. However, in this process, multiple genes possibly unrelated to hypertension may have been selected together with the genetic determinants of hypertension (Carley et al., 2000). This study indicated that Spontaneously Hypertensive Rats differ from Wistar Kyoto rats, but not from Spontaneously Hypertensive Rats treated with Enalapril maleate, in terms of arterial pH and theta frequency. This feature may be due to genetic determinants unrelated to hypertension. In sharp contrast, the persistence of differences in the peak of heart period decrease and the peak of theta frequency increase during phasic hypertensive events between Spontaneously Hypertensive Rats and Spontaneously Hypertensive Rats treated with Enalapril maleate demonstrates that the observed reduction in central autonomic control of the cardiovascular system in Spontaneously Hypertensive Rats is not an irreversible consequence of inherited genetic determinants. Rather, the comparison between Spontaneously Hypertensive Rats and Spontaneously Hypertensive Rats treated with Enalapril maleate indicates that the observed differences in central autonomic control are the result of the hypertension per se. This work supports the view that the study of cardiovascular regulation in sleep provides fundamental insight on the pathophysiology of hypertension, and may thus contribute to the understanding of this disease, which is a major health problem in European countries (Wolf-Maier et al., 2003) with its burden of cardiac, vascular, and renal complications.

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Shuster, Jaime Lynn. « RECOVERY OF SENSORIMOTOR FUNCTION IN RATS FOLLOWING ACUTE RAPID EYE MOVEMENT SLEEP DEPRIVATION AND CONTROLLED CORTICAL IMPACT ». Cleveland State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=csu1301676196.

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Wilkinson, Christopher Richard. « The application of high precision timing in the high resolution fly's eye cosmic ray detector ». Title page, contents and abstract only, 1998. http://hdl.handle.net/2440/37715.

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This thesis represents work performed by the author on the development of the High Resolution Fly's Eye (HiRes) detector for the study of extremely high energy (>10 [superscript 18] eV) cosmic rays. Chapter 1 begins with an review of this field. This chapter details the development of the field, the physics questions we seek to answer, and our current understanding based on experimental and theoretical results. It provides the basis for understanding why detectors such as HiRes are being constructed. This review leads into chapter 2, which discuses the development of cosmic ray induced extensive air showers (EAS) and the techniques used to study them. Particular emphasis is placed upon the air fluorescence technique utilised by HiRes. The two site HiRes prototype detector is then discussed in detail in chapter 3. This covers the different components that form the detector, together with details of the calibration performed to extract useful information from the data. Chapter 4 discusses the installation and subsequent testing of GPS based clock systems for the two sites that make up the HiRes prototype detector. The entire timing system was checked, and some previously hidden bugs fixed. This chapter concludes with work performed on the time to digital converter calibration for the second HiRes site. The high relative timing accuracy provided by the GPS clocks allowed the use of timing information in programs to reconstruct the arrival directions of cosmic rays. Chapter 5 covers the development of a program to use geometrical and timing information to reconstruct EAS viewed by both HiRes sites. This chapter concludes with an evaluation of the likely reconstruction accuracy of the new HiRes (stage1) detector. A well reconstructed EAS trajectory is the first step in the determination of more interesting parameters such as primary particle energy. Chapter 6 covers the collation and analysis of EAS viewed by the both sites of the prototype detector. This includes an evaluation of effects such as the atmosphere, and an estimation of the performance of the new (stage 1) HiRes detector based on results with the prototype detector. Finally the conclusions from this thesis are summarised and sugestions made for further follow up work.
Thesis (Ph.D.)--Department of Physics and Mathematical Physics, 1998.

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Träisk, Frank. « Evaluation of the infrared reflection method for saccadic eye movement velocity analysis / ». Stockholm, 2006. http://diss.kib.ki.se/2006/91-7140-609-3/.

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Murray, Bryon Michael. « Determination of eye dose from personnel monitoring devices in medical institutions ». Thesis, Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/17040.

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Tessem, May-Britt. « Metabolic effects of ultraviolet radiation on the anterior part of the eye ». Doctoral thesis, Norwegian University of Science and Technology, Faculty of Medicine, 2006. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-742.

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Ultraviolet radiation (UV-R) is an environmental factor known to increase the risk of developing an irreversible opacification of the lens (cataract). Increased irradiance of UV-R to the earth because of depletion of stratospheric ozone is of current concern considering cataract formation. Detailed metabolic information from the cornea, lens and aqueous humour might give valuable knowledge on the biochcemical processes occurring in the eye after exposure to UV-R, and thereby a better understanding of the mechanisms by which UV-R induces cataractogenesis. The purpose of this thesis was to study metabolic effects of exposure to UV-R on the anterior part of the eye. Effects of UV-B (280-315 nm) and UV-A (315-400 nm) on the aqueous humour, cornea and the lens from animal models were investigated by ¹H nuclear magnetic resonance (NMR) spectroscopy. Since the lens is composed of functionally distinct anatomical compartments, with different metabolic activity, biochemical changes in various compartments of the lens were analyzed.

Application of NMR-based metabonomics was effective to analyze metabolic changes in the anterior part of the eye after exposure to UV-R. High-resolution (HR) magic angle spinning (MAS)¹H NMR spectroscopy provided high quality spectra from intact tissue of cornea and lens, and provided important information about metabolic alteration occurring in these tissues after exposure to UV-R. The results from this thesis show that in vivo UV-B radiation affects metabolism of the anterior compartments of the eye. Metabolic changes were observed in aqueous humour, cornea, lens and in the different compartments of the lens. The antioxidants, glutathione and ascorbate, several amino acids, high energetic phosphates, and compounds important for membrane building and osmoregulation were substantially altered after exposure to UV-B radiation. Several biochemical effects such as oxidation, membrane disruption, osmoregulatory problems, lipid peroxidation, problems with cellular signalling and impairment of growth and protein synthesis were suggested. After UV-A exposure, no observable metabolic alterations were found in the anterior part of the eye in the present animal models.

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Majeke, Lunga. « Preliminary investigation into estimating eye disease incidence rate from age specific prevalence data ». Thesis, University of Fort Hare, 2011. http://hdl.handle.net/10353/464.

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This study presents the methodology for estimating the incidence rate from the age specific prevalence data of three different eye diseases. We consider both situations where the mortality may differ from one person to another, with and without the disease. The method used was developed by Marvin J. Podgor for estimating incidence rate from prevalence data. It delves into the application of logistic regression to obtain the smoothed prevalence rates that helps in obtaining incidence rate. The study concluded that the use of logistic regression can produce a meaningful model, and the incidence rates of these diseases were not affected by the assumption of differential mortality.

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Nguyen, Anthony Giang. « Rate control based on human visual perception characteristics and its application in encoding time-lapse video / ». Thesis, Connect to this title online ; UW restricted, 2002. http://hdl.handle.net/1773/5921.

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Bhagavatheeshwaran, Govind. « Magnetic Resonance Imaging of the Rat Retina ». Worcester, Mass. : Worcester Polytechnic Institute, 2008. http://www.wpi.edu/Pubs/ETD/Available/etd-041608-144837/.

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Thesis (Ph.D.)--Worcester Polytechnic Institute.
Keywords: Mn54-autoradiography, rat retina, manganese enchanced mri, rcs rat, magnetic resonance imaging, retinal degeneration, high-resolution mri, blood volume imaging Includes bibliographical references (leaves 211-226).

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Seedorff, Michael Thomas. « Methods for testing for group differences in highly correlated, nonlinear eye-tracking data ». Diss., University of Iowa, 2018. https://ir.uiowa.edu/etd/6279.

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Data resulting from eye-tracking experiments allows researchers to analyze the decision making process as study participants consider alternative items prior to the ultimate end point selection. The aim of such an analysis is to extract the underlying cognitive decision making process that develops throughout the experiment. Resulting data can be difficult to analyze, however, as eye-tracking curves have very high autocorrelation values which consists of measurements that are milliseconds apart, as mandated by the nature of eye movements. We propose an analytic approach to eye-tracking data that tests for statistically significant differences at every time point along the curve while calculating an appropriate familywise error rate correction which is based upon an autoregressive correlation assumption of the test statistics. Our technique has been implemented in the R package BDOTS with various extensions relevant to the real-world analysis of highly correlated nonlinear data. A popular alternative approach to analyzing eye-tracking data is to fit mixed models to the area under the curve. Through simulation studies we provide evidence for the benefit of using information criterion measures in selection of the random effects structure and make an argument against current industry-standard approaches such as sequential likelihood ratio tests or always using a maximal random effects structure.

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Blissitt, Martyn. « Olfactory discrimination of ewe urine odours by rams ». Thesis, University of Edinburgh, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.293089.

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Lee, Jeffrey C. « ARCHITECTURAL CONSIDERATIONS FOR A VARIABLE BIT RATE DATA ACQUISITION TELEMETRY ENCODER ». International Foundation for Telemetering, 2007. http://hdl.handle.net/10150/604502.

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ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada
Modern telemetry systems require flexible bit rate telemetry encoders in order to optimize mission formats for varying data rate requirements and/or signal to noise conditions given a fixed transmitter power. Implementing a variable bit rate telemetry encoder requires consideration of several possible architectural topologies that place different system requirements on data acquisition modules within the encoder in order to maintain adequate signal fidelity of sensor information. This paper focuses on the requirements, design considerations and tradeoffs associated with differing architectural topologies for implementing a variable bit rate encoder and the resulting implications on the encoder systems data acquisition units.

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Hughes, Michelle Ann. « Molecular analysis of ovulation rate in the Cambridge ewe ». Thesis, Bangor University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.295279.

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Abou, Zeid Elias. « Multi-rate predictive control scheme for a robotic eye/head system integrating visual and self-motion cues ». Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=40801.

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In primates, the vestibular-ocular reflex (VOR) is known to stabilize gaze during head perturbations. Also, the internal brain circuits controlling eye movements are found to operate with neural delays much smaller than delays in visual processing pathways (~2 ms vs. 150 ms). Based on these biological findings, we present a unified multi-rate biomimetic gaze controller integrating VOR mechanisms (self-motion cues) with tracking (pursuit and saccades) for a robotic head with two cameras. The controller uses automatic parametric switching in shared premotor circuits to alternate between two movements types: slow phase (smooth pursuit) relying on visual feedback, and fast phase (blind corrective jumps) producing nystagmus. Similar to the mammalian gaze system, in the absence of a visual target (in dark), the controller generates vestibular nystagmus in response to sinusoidal passive head inputs. During fixation or tracking of a target (slow phase), a head-motion sensor (VOR) detects head rotation direction and drives the cameras in the opposite direction so that gaze in space remains on the visual target. A multi-rate scheme coupled with input prediction is used to allow the internal controller to operate at 600 Hz, while the visual system is limited to a 30 Hz frame rate. Since the saccade circuit is effectively blind, the higher rate controller operation allows increasing saccade bandwidths without ringing to over 30 Hz. Adding slip and memory (PDI control) in the visual feedback overcomes inherent delays in the visual system, increases the tracking response bandwidth to around 5 Hz, and improves steady state tracking gain.
Chez les primates, le réflexe oculovestibulaire (ROV) sert à stabiliser le regard durant les perturbations de la tête. Aussi, les circuits cérébrals internes qui contrôllent les mouvements des yeux opèrent avec des délais beaucoup plus courts que les délais dans les régions de traitement visuels (~2 ms vs. 150 ms). En se basant sur ces faits biologiques, nous présentons un contrôleur de regard biomimétic, unifié, et multi-rate, intégrant les mécanismes du ROV et poursuite (pursuit et saccade) pour un système robotique d’une tête surmontée par deux caméras. Le contrôleur change automatiquement les paramètres dans les circuits prémoteurs partagés affin d’altérner entre deux types de mouvements : phase lente (poursuite lisse) dépendant sur un feed-back visuel, et phase rapide (sauts correctifs aveugles) produisant le nystagmus. Comme le système de regard chez les mammifères, en absence d’une cible visuelle, le contrôleur produit un mouvement nystagmus vestibulaire en réponse à des perturbations de la tête. Durant la fixation ou la poursuite (phase lente) d’une cible, un détecteur de mouvement de la tête (ROV) détecte la direction de la rotation et conduit les caméras dans la direction opposée, ainsi le regard reste sur la cible. Un procédé multirate couplé avec prévision (extrapolation) des signaux d’entrée (le système visuel étant limité à 30 Hz) est utilisé pour permettre d’opérer le contrôleur interne à 600 Hz. Comme le circuit de saccade est effectivement aveugle, l’opération du controlleur interne à cette fréquence élevée permette d’augmenter la bande passante des saccades jusqu’à plus que 30 Hz sans sonneries. L’ajout de dérivée et intégration (contrôle PDI) dans le feed-back visuel surmonte les délais dans le système visuel, augmente la bande passante de la réponse jusqu’à ~5 Hz, et améliore le gain de la poursuite à l’état d’équilibre.

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Mayes, Caryl Ann. « A screen for novel genes involved in Drosophila compound eye development and the cloning and characterisation of rasputin, a homologue of G3BP ». Thesis, University of Sussex, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.323053.

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Cooper, A. C. « The endocrine control of ovulation and ovulation rate in the ewe ». Thesis, University of Nottingham, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.383767.

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Silva, Germana Alegro da [UNESP]. « Efeitos do citrato de sildenafila sobre a neuroproteção na neuropatia óptica, em ratos (Lewis/SsNHsd) com glaucoma agudo ». Universidade Estadual Paulista (UNESP), 2014. http://hdl.handle.net/11449/121866.

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Projetam-se que mais de 80 milhões de pessoas no mundo e um número significativo de animais serão atingidos pelo glaucoma até o final desta década. A doença perpetra-se como sem solução, obrigando a que se desenvolvam alternativas terapêuticas mais eficazes. A perda de visão decorre da morte de células ganglionares da retina (CGR) e de seus axônios, que compõem as fibras do nervo óptico. Avanços na compreensão da fisiopatologia evidenciam que isquemia local e que anormalidades de perfusão são condições decisivas na patogênese da neuropatia. Mostrou-se que o Sildenafila, fármaco vasodilatador, inibe a fosfodiesterase do tipo 5 (PDE-5), aumenta os níveis de guanosina monofosfato cíclica, prolonga efeitos do óxido nítrico (ON) e aumenta a sobrevida celular em modelos de lesão isquêmica. Objetivou-se avaliar o efeito neuroprotetor do tratamento citrato de sildenafila em ratos com hipertensão ocular aguda induzida, à histopatologia e à morfometria da retina e quanto à avaliação da expressão de marcadores relacionados à sobrevivência das CGR, empregando-se a imunohistoquímica (IHC) e a marcação TUNEL. Os Parâmetros histológicos observados foram: alterações celulares, vasculares e teciduais e os morfométricos foram: espessura das camadas da retina e contagem de células ganglionares. À IHC, observou-se a marcação da caspase-9, da caspase-3, do Bcl-2, da NOS-2, da PDE- 5, e da PDE-6. Foram avaliados olhos de 27 ratos, machos, adultos (Lewis/SsNHsd). Compuseram-se cinco grupos, um grupo controle composto por 3 animais, sem glaucoma e sem tratamento, e quatro grupos tratados compostos, cada um, por 6 animais com glaucoma agudo unilateral induzido, dos quais 3 foram tratados com Sildenafila e 3 tratados com placebo. Esses grupos foram separados conforme dia de indução do glaucoma até a eutanásia, em 1, 13, 14 e 20 dias, e receberam diferentes doses e períodos de tratamento. A indução do glaucoma ...
Protrude more than 80 million people worldwide and a significant number of animals are affected by glaucoma by the end of this decade. The disease perpetrates as unresolved, forcing them to develop more effective therapeutic alternatives. Vision loss results from the death of retinal ganglion cells (RGCs) and their axons, the fibers that make up the optic nerve. Advances in understanding the pathophysiology show that local ischemia and perfusion abnormalities are critical in the pathogenesis of neuropathy conditions. It has been shown that sildenafil drug vasodilator, inhibits phosphodiesterase type 5 (PDE -5) increases the levels of cyclic guanosine monophosphate extends effects of nitric oxide (NO) and increases cell survival in models of ischemic injury. Aimed to evaluate the neuroprotective effect of sildenafil citrate treatment in rats with induced acute ocular hypertension, by histopathological and morphometric examination of the retina and the evaluation of the expression of markers related to RGC survival , using immunohistochemistry (IHC) and TUNEL labeling. The observed histological parameters: cellular , tissue and vascular and morphometric changes were: thickness of the layers of the retina and ganglion cell count , IHC, there was labeling of caspase-9, caspase-3, Bcl-2, NOS-2, PDE-5, and PDE-6. Eyes of 27 rats, adult (Lewis/ SsNHsd) were evaluated after acute unilateral elevation of intraocular pressure (IOP). Composed by five groups , a control group of 3 animals without glaucoma and untreated and four treated groups consisting of 6 animals with induced unilateral acute glaucoma, of which 3 were treated with Sildenafil and 3 with placebo, these groups were separated by days of glaucoma´s induction to euthanasia, and they received districts dose and period of treatment. The induction of glaucoma was made by anterior chamber paracentesis needle attached to a bottle of saline solution 0.9 %, provided the height of 150 cm ...

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Silva, Germana Alegro da. « Efeitos do citrato de sildenafila sobre a neuroproteção na neuropatia óptica, em ratos (Lewis/SsNHsd) com glaucoma agudo / ». Jaboticabal, 2014. http://hdl.handle.net/11449/121866.

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Orientador: José Luiz Laus
Banca: Renée Laufer Amorim
Banca: Andréia Vitor Couto do Amaral
Resumo: Projetam-se que mais de 80 milhões de pessoas no mundo e um número significativo de animais serão atingidos pelo glaucoma até o final desta década. A doença perpetra-se como sem solução, obrigando a que se desenvolvam alternativas terapêuticas mais eficazes. A perda de visão decorre da morte de células ganglionares da retina (CGR) e de seus axônios, que compõem as fibras do nervo óptico. Avanços na compreensão da fisiopatologia evidenciam que isquemia local e que anormalidades de perfusão são condições decisivas na patogênese da neuropatia. Mostrou-se que o Sildenafila, fármaco vasodilatador, inibe a fosfodiesterase do tipo 5 (PDE-5), aumenta os níveis de guanosina monofosfato cíclica, prolonga efeitos do óxido nítrico (ON) e aumenta a sobrevida celular em modelos de lesão isquêmica. Objetivou-se avaliar o efeito neuroprotetor do tratamento citrato de sildenafila em ratos com hipertensão ocular aguda induzida, à histopatologia e à morfometria da retina e quanto à avaliação da expressão de marcadores relacionados à sobrevivência das CGR, empregando-se a imunohistoquímica (IHC) e a marcação TUNEL. Os Parâmetros histológicos observados foram: alterações celulares, vasculares e teciduais e os morfométricos foram: espessura das camadas da retina e contagem de células ganglionares. À IHC, observou-se a marcação da caspase-9, da caspase-3, do Bcl-2, da NOS-2, da PDE- 5, e da PDE-6. Foram avaliados olhos de 27 ratos, machos, adultos (Lewis/SsNHsd). Compuseram-se cinco grupos, um grupo controle composto por 3 animais, sem glaucoma e sem tratamento, e quatro grupos tratados compostos, cada um, por 6 animais com glaucoma agudo unilateral induzido, dos quais 3 foram tratados com Sildenafila e 3 tratados com placebo. Esses grupos foram separados conforme dia de indução do glaucoma até a eutanásia, em 1, 13, 14 e 20 dias, e receberam diferentes doses e períodos de tratamento. A indução do glaucoma ...
Abstract: Protrude more than 80 million people worldwide and a significant number of animals are affected by glaucoma by the end of this decade. The disease perpetrates as unresolved, forcing them to develop more effective therapeutic alternatives. Vision loss results from the death of retinal ganglion cells (RGCs) and their axons, the fibers that make up the optic nerve. Advances in understanding the pathophysiology show that local ischemia and perfusion abnormalities are critical in the pathogenesis of neuropathy conditions. It has been shown that sildenafil drug vasodilator, inhibits phosphodiesterase type 5 (PDE -5) increases the levels of cyclic guanosine monophosphate extends effects of nitric oxide (NO) and increases cell survival in models of ischemic injury. Aimed to evaluate the neuroprotective effect of sildenafil citrate treatment in rats with induced acute ocular hypertension, by histopathological and morphometric examination of the retina and the evaluation of the expression of markers related to RGC survival , using immunohistochemistry (IHC) and TUNEL labeling. The observed histological parameters: cellular , tissue and vascular and morphometric changes were: thickness of the layers of the retina and ganglion cell count , IHC, there was labeling of caspase-9, caspase-3, Bcl-2, NOS-2, PDE-5, and PDE-6. Eyes of 27 rats, adult (Lewis/ SsNHsd) were evaluated after acute unilateral elevation of intraocular pressure (IOP). Composed by five groups , a control group of 3 animals without glaucoma and untreated and four treated groups consisting of 6 animals with induced unilateral acute glaucoma, of which 3 were treated with Sildenafil and 3 with placebo, these groups were separated by days of glaucoma's induction to euthanasia, and they received districts dose and period of treatment. The induction of glaucoma was made by anterior chamber paracentesis needle attached to a bottle of saline solution 0.9 %, provided the height of 150 cm ...
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Viñoles, Gil Carolina. « Effect of nutrition on follicle development and ovulation rate in the ewe / ». Uppsala : Dept. of Clinical Chemistry, Swedish Univ. of Agricultural Sciences, 2003. http://epsilon.slu.se/v165.pdf.

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Pazos, López Marta. « Rat optic nerve head anatomy within three- dimensional histomorphometric reconstructions of normal and early experimental glaucoma eyes ». Doctoral thesis, Universitat Autònoma de Barcelona, 2016. http://hdl.handle.net/10803/381080.

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Objetciu: Reconstruir en 3D caps del nervi òptic (CNOs) de rata camb glaucoma experimental (GExp) precoç unilateral, per proporcionar la primera descripció histomorfomètrica del CNO de controls normales i amb GExp primerenc en aquesta espècie. Métodos: Es va injectar sèrum salí hipertònic unilateralment en les venes epiesclerals de 8 rates noruegues que van ser sacrificades 4 setmantes després (fixació-perfusió). Cinc observadors enmascarats graduaren el dany de seccions del nervi òptic (NO) orbitari (1 Normal-5 Extens). Es van reconstruir en 3D, es van visualitzar, deliniar i parametritzar els CNOs i l’esclera peripapil·lar. Els paràmetres globals i específics per ull van ser avaluats conjuntament i regionalment amb un model d’efectes linials mixtes amb criteris de significació ajustats per a comparacións múltiples. Resultats: El CNO de la rata consisteix en 2 obertures esclerals (una superior neurovascular i una altra otra inferior arterial) separades por una cingla escleral. Dins l’obertura superior, el nervi es recolza un una prominent extensió de la Membrana de Bruch’s (MB) superiorment i està rodejat d’un plexe vascular. El NO i l’Obertura Anterior del Canal Escleral (ASCO) van expandir-se significativament en 7 dels 8 ulls amb GExp. En almenys 5 ulls amb GExp van detectar-se expansions significativae de l’Obertura de la MB (BMO) (3-10%), de l’ASCO y de l’Obertura Posterior del Canal Escleral (PSCO) (8-21% i 8-41% respectivament). L’expansió del NO va correlacionar-se significativament amb el grau de dany (R2=0.668, p<0.05). Conclusions: La complexitat 3D del CNO de rata y el gau en el què es diferencia de la del primat han estat infravalorats en estudis previs en 2D. En el CNO de rata, el NO, el BMO que el rodeja I el canal neurovascular s’expandeixen de manera precoç en resposta a l’elevació experimental crònica de PIO. Aquestes troballes aporten nous punts de referència i objectius d’imatge per detectar el desenvolupament de la neuropatia glaucomatosa experimental en ulls de rata.
Objetivo: Reconstruir en 3D cabezas del nervio óptico (CNOs) de rata con glaucoma experimental (GExp) precoz unilateral, para proporcionar la primera descripción histomorfométrica de la CNO de controles normales y GExp precoz en esta especie. Métodos: Se inyectó suero salino hipertónico unilaterlamente en las venas epiesclerales de 8 ratas noruegas que se sacrificaron 4 semanas después (fijación-perfusión). Cinco observadores enmascarados graduaron el daño de secciones del nervio óptico (NO) orbitario (1 Normal-5 Extenso). Se reconstruyeron en 3D, se visualizaron, delinearon y parametrizaron las CNOs junto con la esclera peripapilar. Los parámetros globales y específicos por ojo fueron evaluados conjuntamente y regionalmente con un modelo de efectos lineares mixtos con criterios de significación ajustados para comparaciones múltiples. Resultados: La CNO de la rata consiste en 2 aperturas esclerales (una superior neurovascular y otra inferior arterial) separados por una cincha escleral. Dentro de la apertura superior, el nervio se apoya en una prominente extensión de la Membrana de Bruch’s (MB) superiormente y está rodeado de un plexo vascular. El NO y la Apertura Anterior del Canal Escleral (ASCO) se expandieron significativamente en 7 de 8 ojos con GExp. En al menos 5 ojos con GExp se detectaron expansiones significativas de la apertura de la MB (BMO) (3-10%), de la ASCO y de la Apertura Posterior del Canal Escleral (PSCO) (8-21% y 8-41% resp.). La expansión del NO se correlacionó significativamente con el grado de daño (R2=0.668, p<0.05). Conclusiones: La complejidad 3D de la CNO de rata y el grado en el que se diferencia de la del primate han sido infravalorados en los estudios previos en 2D. En la CNO de rata, el NO, el BMO que lo rodea y el canal neurovascular se expanden de manera temprana en respuesta a la elevación experimental crónica de PIO. Estos hallazgos proporcionan nuevos puntos de referencia y objetivos de imagen para detectar el desarrollo de la neuropatía glaucomatosa experimental en ojos de rata.
Purpose: To Three-Dimensionally (3D) reconstruct rat optic nerve heads (ONHs) with varying stages of unilateral early experimental glaucoma (EG), so as to provide the first histomorphometrical description of nomal controls and early EG ONH anatomy in this species. Methods: Hypertonic saline was unilaterally injected into the episcleral veins of 8 Brown Norway rats and animals were sacrificed 4 weeks later by perfusion fixation. Orbital optic nerve (ON) crosssections from were graded (1 normal, 5 extensive injury) by 5 masked observers. ONH’s with peripapillary ONH sclera were 3D reconstructed, visualized, delineated, and parameterized. Overall and animal-especific EG versus control eye ONH parameters differences were assessed globally and regionally by linear mixed effect models with significance criteria adjusted for multiple comparisons. Results: The rat ONH consists of 2 scleral openings (a superior neurovascular and inferior arterial) separated by a scleral sling. Within the superior opening, the nerve abuts a prominent extension of Bruch’s Membrane (BM) superiorly and is surrounded by a vascular plexus. Expansions of the ON and anterior scleral canal opening (ASCO) achieved statistical significance overall and in 7 of 8 EG eyes. In at least 5 EG eyes, significant expansions in Bruch’s Membrane Opening (BMO) (3-10%), the ASCO and Posterior Scleral Canal Openings (PSCOs) (8-21% and 8-41%, respectively) were detected. ON expansion was significantly correlated to ON damage (R2=0.668, p<0.05). Conclusions: The 3D complexity of the rat ONH and the extent to which it differs from the primate have been under-appreciated within previous 2D studies. In the rat ONH, the ON ansd surrounding BMO and neurovascular canal expand early in their response to chronic experimental IOP elevation. These findings provide phenotypic landmarks and imaging targets for detecting the development of EG optic neuropathy in the rat eye.

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Giuliano, Ryan. « Where the Heart Meets the Mind’s Eye : Associations Between Cardiac Measures of Autonomic Activity and Selective Attention in Children and Adults ». Thesis, University of Oregon, 2017. http://hdl.handle.net/1794/22624.

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Multiple theoretical frameworks posit that interactions between the autonomic nervous system and higher-order neural networks are crucial for cognitive regulation. However, few studies have directly examined whether autonomic physiology influences brain activity during cognitive tasks, and even fewer of those studies have examined both autonomic branches when doing so. Measures of selective attention derived from event-related brain potentials (ERPs) are particularly well-suited for addressing this question, given that ERP selective attention tasks are designed to control for the influences of psychomotor processes and arousal and are predictive of higher-order cognitive function in children and adults. Such research is particularly promising for understanding how early adversity impacts neurocognitive development in children, given that stress experienced early in life impacts both autonomic function and selective attention. Here, a broad literature review is presented, integrating findings across studies of autonomic physiology, cognition, and brain activity in children and adults (Chapter 1). Then, two experiments are described where cardiac measures of parasympathetic and sympathetic activity were recorded concurrently with ERPs during an auditory selective task in a sample of adults (Chapter 2) and in a sample of preschool-aged children (Chapter 3). Results from both experiments demonstrate a key role for the sympathetic nervous system in selective attention for adults and children, such that greater sympathetic activity is associated with larger effects of selective attention on ERPs. These findings are then reviewed with suggestions for how existing models of neurovisceral integration might be updated to better emphasize the role of sympathetic nervous system activity in neurocognitive processes, emphasizing measures of threat-related and reward-related arousal, as represented by galvanic skin response and pre-ejection period, respectively (Chapter 4). Future directions are also discussed, including recommendations for future studies of neurovisceral integration to examine associations between physiology, behavior, and brain activity at the single-trial level, to incorporate participants from more diverse backgrounds of life experience, and to examine the plasticity of autonomic mechanisms implicated in neurocognitive function.

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De, Graaf Brandon Michael. « Determining the Effect of Shielding for an Eye Exposed to Secondary Particles Produced by Galactic Cosmic Rays using MCNPX Modeling ». University of Cincinnati / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1288379556.

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Le, Roy-Le Gaouyat Brigitte. « Proprietes oestrogeniques de l'androst-5-ene beta-diol : un steroide hermaphrodiol ». Rennes 1, 1992. http://www.theses.fr/1992REN1B022.

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Zorka, Grgić. « Uticaj prevremenog rođenja na rast oka i proces emetropizacije ». Phd thesis, Univerzitet u Novom Sadu, Medicinski fakultet u Novom Sadu, 2016. https://www.cris.uns.ac.rs/record.jsf?recordId=96912&source=NDLTD&language=en.

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Stopa prematuriteta konstantno raste, a sve više prevremeno rođenih beba koje prežive neonatalni i perinatalni period zahteva adekvatno sistemsko i oftalmološko praćenje i tretman. Prematuritet sam po sebi, predstavlja rizik za razvoj vida. Taj rizik dodatno povećava prisustvo prematurne retinopatije i refraktivnih mana. Skrining i tretman promena na retini u sklopu prematuriteta, kao i optička korekcija refraktivnih mana obezbeđuju uslove za razvoj vida. Cilj ovog istraživanja je bio utvrditi promene biometrijskih karakteristika oka prematurusa, sa i bez prematurne retinopatije, tokom šestogodišnjeg praćenja, utvrditi refraktivni status ove dve grupe dece sa šest godina, te povezati promene biometrijskih karakteristika oka sa refrakcijom. U ispitivanje je uključeno 192 prevremeno rođena deteta (384 oka). Vršena su tri pregleda, u uzrastu od 3 meseca, 12 meseci i 6 godina starosti. Nakon prvog pregleda ispitivani uzorak je, u zavisnosti od nalaza na očnom dnu, podeljen na bebe sa prematurnom retinopatijom i bebe bez ovog oboljenja, a kako bi se uporedile proučavane karakteristike. U sva tri navedena uzrasta je pregledano očno dno i merene su tri glavne biometrijske karakteristike koje utiču na refraktivni status: aksijalna dužina oka, dubina prednje očne komore i debljina očnog sočiva. Sa šest godina je određena refrakcija, uključujući zakrivljenost rožnjače odnosno kornealni astigmatizam, vidna oštrina bez korekcije refraktivne mane, a zatim i nakon korekcije. Ostali neophodni podaci su dobijeni iz medicinske dokumentacije. Pokazano je da prematurna retinopatija utiče na refraktivni status i vidni ishod sa šest godina, pre svega uticajem na zakrivljenost rožnjače, aksijalnu dužinu oka i dubinu prednje očne komore, dok su promene debljine očnog sočiva bez posebnog značaja. Vidne oštrine oba oka u predškolskom uzrastu prevremeno rođene dece sa prematurnom retinopatijom su statistički značajno manje kada se uporede sa vidnim oštrinama prevremeno rođene dece bez retinopatije, ali razlika u ovim dvema vrednostima gubi statističku značajnost nakon optičke korekcije. Učestalost astigmatizma u prematurnoj populaciji sa 6 godina je visoka, a od onih koji imaju astigmatizam u tom uzrastu, više od dve trećine je imalo prematurnu retinopatiju. Ukupna učestalost miopije, hipermetropije i emetropije u prematurnoj populaciji sa 6 godina je 18,9%, 54,7% i 13,2%, a preostalih 13,2% su anizometropi. U više od trećine dece, sa prematurnom retinopatijom u najranijem uzrastu, sa šest godina postoji gubitak vidne sposobnosti, koji je najčešće blag, no može biti i potpun.
The number of babies born prematurely is constantly growing, so more and more of them need appropriate systemic and ophthalmologic monitoring and treatament. Prematurity itself, represents a risk for the development of vision. This risk further reinforces the presence of retinopathy of prematurity and refractive errors. Screening and treatment of retinopathy, as well as optical correction of refractive errors provide adequate conditions for the development of vision. The aim of this study was to determine changes of biometric features of eyes of the prematurely born infants, with and without retinopathy of prematurity, during the six-year follow-up. We also want to determine the refractive status of these two groups of children in the six year, and to link changes of biometric features with their eye refraction. The study included 192 prematurely born children (384 eyes). The examinations were performed at 3 months, 12 months and 6 years and they included fundus examination and measurements of the ocular axial length, anterior chamber depth and lens thickness. After dividing the subjects into two groups, based on the results of the fundus examination at 3 months, the results of the children with and without retinopathy were compared. At the age of six we also determine the refraction of eyes, including the curvature of the cornea and corneal astigmatism, visual acuity without correction of refractive error, and then after it. Other necessary data were obtained from medical documentation. It is shown that retinopathy of prematurity affects the refractive status and visual outcome at sixth year, primarily by the changes of curvature of the cornea, the axial length of the eye and the depth of the anterior chamber, while the change in the lens thickness has no significance. Visual acuity in both eyes in the preschool age preterm born children with retinopathy of prematurity are significantly less, when compared to visual acuity in preterm infants without retinopathy, but the difference in these two values lost statistical significance after optical correction. The rate of astigmatism in preterm population of six years is high, and of those who have astigmatism in this age group, more than two-thirds had retinopathy of prematurity. The overall incidence of myopia, hypermetropia and emetropia in the prematurely born, six years old children is 18.9%, 54.7% and 13.2%, and the remaining 13.2% have anisometropia. In more than a third of children with retinopathy of prematurity at an early age, with six years, there has been loss of visual acuity, which is usually mild, but it can be complete.

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Clarke, Linda Sue. « Breed group effects on pregnancy rate and ewe performance in different seasons of the year ». Thesis, Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/53062.

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Thirty-one Dorset (D), 24 Finnish Landrace (F), 35 Barbados Blackbelly x Dorset (BD), 10 Dorset x Finn (F), 24 Finn x Dorset (FD) and 35 grade Rambouillet (R) ewes were exposed to rams in various seasons. Ewes were born in 1979 or 1980; no R ewes were born in 1980. Ewes were bred in April, 1980 (APR80); November, 1980 (NOV80); August, 1981 (AUG81); May, 1982 (MAY82); and April, 1983 (APR83). Ewes born in 1980 entered the study in NOV80. The analytical model used to describe ewe performance included effects of ewe birth year (EBY), breed/EBY, season/EBY, breed x season/EBY and ewe (random).
Master of Science

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Wallace, Jacqueline Moira. « The role of follicle stimulating hormone in the control of ovulation rate in the ewe ». Thesis, University of Edinburgh, 1985. http://hdl.handle.net/1842/19389.

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Liao, Joseph. « Influence of Age on the Rate of Estimated Retinal Ganglion Cell Counts in Healthy Eyes ». Thesis, The University of Arizona, 2017. http://hdl.handle.net/10150/623468.

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A Thesis submitted to The University of Arizona College of Medicine - Phoenix in partial fulfillment of the requirements for the Degree of Doctor of Medicine.
To evaluate aging effects on estimated retinal ganglion cell (RGC) counts in healthy eyes. This was a longitudinal observational cohort study involving 100 eyes of 50 healthy patients recruited from Diagnostic Innovations in Glaucoma Study (DIGS) and African Descent and Glaucoma Evaluation Study (ADAGES). Subjects were followed for an average of 4.9 ± 2.6 years. All patients underwent standard automated perimetry (SAP) visual field testing and optical coherence tomography (OCT) on follow‐up visits. Estimated RGC counts were obtained by a previously described method using SAP sensitivity thresholds and OCT retinal nerve fiber layer measurements. Linear mixed effects models were used to investigate the relationship between age and rates of change in estimated RGC counts over time. The mean age at baseline was 49.4 ± 16.2 years, ranging from 22.9 to 90.0 years. At baseline, average estimated RGC count was 1,144,010 ± 222,084 cells. In univariable model, the rate of change in estimated RGC count was ‐6,880 ± 2,398 cells/year (P = 0.004). Analyses were also performed adjusting for baseline age, gender, race, OCT signal strength and axial length. After adjusting for confounding factors, the rate of estimated RGC loss was ‐6,276 ± 2,441 cells/year (P = 0.010) in healthy eyes. There was a significant age‐related decline in estimated RGC counts obtained from combining information from structural and functional tests. After accounting for confounding factors, the age‐related decline found was similar to those obtained in previous histologic studies reported on the literature.

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Hager, Michele LynnManeca. « A Study of Contact Lens Comfort in Patients Wearing Comfilcon A Soft Contact Lenses Compared to Their Habitual Soft Contact Lenses ». The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1243711014.

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Eakins, Kaylee Marie. « Impact of Noise Level on Task Performance and Workload and Correlation to Personality ». Wright State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=wright1527162272457947.

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Berg, Simon, et Victor Elfström. « IRRBB in a Low Interest Rate Environment ». Thesis, KTH, Matematisk statistik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-273589.

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Financial institutions are exposed to several different types of risk. One of the risks that can have a significant impact is the interest rate risk in the bank book (IRRBB). In 2018, the European Banking Authority (EBA) released a regulation on IRRBB to ensure that institutions make adequate risk calculations. This article proposes an IRRBB model that follows EBA's regulations. Among other things, this framework contains a deterministic stress test of the risk-free yield curve, in addition to this, two different types of stochastic stress tests of the yield curve were made. The results show that the deterministic stress tests give the highest risk, but that the outcomes are considered less likely to occur compared to the outcomes generated by the stochastic models. It is also demonstrated that EBA's proposal for a stress model could be better adapted to the low interest rate environment that we experience now. Furthermore, a discussion is held on the need for a more standardized framework to clarify, both for the institutions themselves and the supervisory authorities, the risks that institutes are exposed to.
Finansiella institutioner är exponerade mot flera olika typer av risker. En av de risker som kan ha en stor påverkan är ränterisk i bankboken (IRRBB). 2018 släppte European Banking Authority (EBA) ett regelverk gällande IRRBB som ska se till att institutioner gör tillräckliga riskberäkningar. Detta papper föreslår en IRRBB modell som följer EBAs regelverk. Detta regelverk innehåller bland annat ett deterministiskt stresstest av den riskfria avkastningskurvan, utöver detta så gjordes två olika typer av stokastiska stresstest av avkastningskurvan. Resultatet visar att de deterministiska stresstesten ger högst riskutslag men att utfallen anses vara mindre sannolika att inträffa jämfört med utfallen som de stokastiska modellera genererade. Det påvisas även att EBAs förslag på stressmodell skulle kunna anpassas bättre mot den lågräntemiljö som vi för tillfället befinner oss i. Vidare förs en diskussion gällande ett behov av ett mer standardiserat ramverk för att tydliggöra, både för institutioner själva och samt övervakande myndigheter, vilka risker institutioner utsätts för.

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Zanoni, Diogo Sousa [UNESP]. « Análise histológica, morfométrica, expressão de genes, proteínas e western blot na retina de ratos com glaucoma induzido e tratados com citrato de sildenafil ». Universidade Estadual Paulista (UNESP), 2018. http://hdl.handle.net/11449/180638.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
O glaucoma é a principal causa global de cegueira irreversível e o número de pessoas com glaucoma em todo o mundo aumentará para 111,8 milhões em 2040, mesmo com os tratamentos vigentes. Deste modo, enseja uma necessidade de desenvolver terapias neuroprotetoras que possam ser usadas para reduzir os efeitos perniciosos do glaucoma, como a morte de células ganglionares da retina (CGR). Avanços na compreensão da fisiopatologia do glaucoma é um fator chave na compreensão da patogênese da neuropatia glaucomatosa. Neste contexto a isquemia retiniana desempenha um papel central em várias doenças da retina. A patogênese da isquemia retiniana envolve alterações temporais da morfologia e morfometria da retina assim como mudanças na expressão gênica e protéica. O Citrato de Sildenafila (SC) mostrou efeito protetor nos modelos de isquemia/reperfusão (I/R) com efeitos neuroprotetores. Contudo, a administração oral de CS, em humanos, encontra inúmeros efeitos colaterais, tais como redução da pressão arterial, dores de cabeça, rubor e congestão nasal são concomitantes,
Glaucoma is the leading global cause of irreversible blindness and the number of people with glaucoma worldwide will increase to 111.8 million by 2040, even with current treatments. Thus, there is a need to develop neuroprotective therapies that can be used to reduce the deleterious effects of glaucoma, such as retinal ganglion cell death (RBC). Advances in understanding the pathophysiology of glaucoma are a key factor in understanding the pathogenesis of glaucomatous neuropathy. In this context, retinal ischemia plays a central role in various diseases of the retina. The pathogenesis of retinal ischemia involves temporal changes in retinal morphology and morphometry as well as changes in gene and protein expression. Sildenafil Citrate (SC) showed protective effect in the ischemia / reperfusion (I / R) models with neuroprotective effects. However, oral administration of CS in humans finds numerous side effects such as reduced blood pressure, headaches, flushing and nasal congestion are concomitant, as well as patients with moderate to severe cardiovascular disease or those undergoing nitrate therapy have increased secondary risks for adverse cardiovascular effects. Thus, we propose that the eye drops administration of CS may be an alternative to the oral route and also be equally neuroprotective in glaucoma and may minimize the undesirable risks in the systemic use of this drug, as well as offer a new approach for the therapeutic intervention in the pathogenesis of neuropathy glaucomatous. If our results are positive, in such a comprehensive study, it may lead to a clinical trial of this safe and promising drug in patients with glaucoma.
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Bergman, Gerald Rae. « Evaluation of exposure to optical radiation used in diagnostic and treatment in medicine and dentistry ». Connect to full-text via OhioLINK ETD Center, 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=mco1095952844.

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Thesis (M.S.)--Medical College of Ohio, 2004.
"In partial fulfillment of the requirements for the degree of Master of Science in Occupational Health." Major advisor: Farhang Akbar. Includes abstract. Document formatted into pages: iv, 75 p. Title from title page of PDF document. Includes bibliographical references (p. 58-68).

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Castro, Glaucia Monteiro de. « Estudo da ação imunomoduladora de gangliosideos sobre a evolução da encefalomielite experimental autoimune (EAE) em ratos Lewis ». [s.n.], 1999. http://repositorio.unicamp.br/jspui/handle/REPOSIP/317519.

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Orientadores: Francesco Langone, Leonilda Maria Barbosa dos Santos
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: A encefalomielite experimental autoimune (EAE) é uma doença mediada por linfócitos T CD4, que penetram através da barreira hematoencefálica promovendo uma reação inflamatória local e edema, responsáveis pela ocorrência das deficiências neurológicas da doença. Como modelo da esclerose múltipla, a EAE tem sido usada na avaliação de estratégias terapêuticas. No presente trabalho, nós investigamos o efeito do tratamento com gangliosídeos na evolução da encefalomielite experimental autoimune. Para tanto foi realizado estudo morfológicojmorfométrico, imunoistoquímico, ensaio de linfoproliferação e dosagem de fator de necrose tumorala (TNF-a) e fator transformador de crescimento-p (TGF- ß). OS resultados mostram que a administração de gangliosídeos na fase efetora leva à supressão parcial ou total dos sinais clínicos, refletindo-se na contagem de infiltrados, onde o número destes foi significativamente menor no cérebro. A avaliação imunológica demonstrou que os animais tratados com gangliosídeos apresentam níveis significativamente menores de TNF-a, uma das principais citocinas envolvidas na gênese da EAE. Estes resultados comprovam a ação imunomoduladora dos gangliosídeos na evolução da EAE, relacionada com a provável inibição na produção do TNF-a devido a supressão na proliferação de linfócitos Th1, o que leva a propor a possibilidade de um novo agente terapêutico para o tratamento da esclerose múltipla
Abstract: The experimental autoimmune encephalomyelitis (EAE) is a disease mediated by CD4 T cells, that penetrate nervous tissue across the blood-brain barrier and promote a local inflammatory reaction and edema, responsible for the occurrence of the neurological deficits of the disease. As a model of the multiple sclerosis, EAE has been used for the evaluation of therapeutic strategies for this pathological condition. In the present work, we investigated the effect on EAE evolution of treatment with gangliosides. The disease was induced in Lewis rats and they received two daily doses of the gangliosides mixture (lOOmg/Kg). The Lewis rats were accompanied for clinical evaluation and sacrificed for morphological, morphometric, and immunohistochemical analysis of the nervous tissue. We also made a proliferation assay, tumor necrosis factor-a (TNF-a) and transforming growth factor- ß (TGF- ß) dosage. The results showed that the administration of gangliosides in the effector phase of EAE leads to the partial or total suppression of the clinical signs. This finding was valiated by the significantly lesser number of inflammatory cell infiltrations in the brain of treated animals. Moreover, the TNF-a levels were smaller in Lewis rats that were immunized and received gangliosides. Our results showed very strong immunomodulatory action of the gangliosides on the evolution of EAE, suggesting that these compound may have an important role in multiple sclerosis therapeutics
Mestrado
Biologia Celular
Mestre em Ciências Biológicas

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Whittow, William. « Specific absorption rate perturbations in the eyes and head by metallic spectacles at personal radio communication frequencies ». Thesis, University of Sheffield, 2004. http://etheses.whiterose.ac.uk/10269/.

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The research in this thesis involves the absorption in the human head of microwaves in the frequency range 0.5 to 3GHz with the excitation positioned in front of the face. It is hypothesised that metallic spectacles can significantly affect the absorption in the head. The effects of metallic spectacles have been primarily investigated using computer modelling. The finite-difference time-domain (FDTD) is the most common computational tool used in bioelectromagnetics. For this research an independent, specially written FDTD code has been used. The accuracy of the code was carefully validated against controls. Two anatomically accurate heads were implemented into the FDTD code. Different shapes and sizes of metallic spectacles were modelled. The materials that the spectacles were made of were also investigated. Realistic and geometric spectacles were considered. Vertically and horizontally polarised plane waves as well as vertically and horizontally orientated dipoles are used as sources. A genetic algorithm (GA) was employed as a search technique to optimise the spectacles for the specific absorption rates (SAR) in the eyes and the head. Measurements were also made of a phantom with metallic spectacles. Results showed good agreement with the FDTD code. Results confirmed the hypothesis that metallic spectacles can significantly affect the SAR in the head and particularly in the eyes.

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Vos, Etienne Eben. « Cosmic ray modulation processes in the heliosphere / Vos E.E ». Thesis, North-West University, 2011. http://hdl.handle.net/10394/7266.

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The solar minimum of 2009 has been identified as an exceptional event with regard to cosmic ray (CR)modulation, since conditions in the heliosphere have reached unprecedented quiet levels. This unique minimum has been observed by the Earth–orbiting satellite, PAMELA, launched in June, 2006, from which vast sets of accurate proton and electron preliminary observations have been made available. These simultaneous measurements from PAMELA provide the ideal opportunity to conduct an in–depth study of CR modulation, in particular charge–sign dependent modulation. In utilizing this opportunity, a three–dimensional, steady–state modulation model was used to reproduce a selection of consecutive PAMELA proton and electron spectra from 2006 to 2009. Thiswas done by assuming full drifts and simplified diffusion coefficients, where the rigidity dependence and absolute value of themean free paths for protons and electrons were sequentially adjusted below 3 GV and 300 MV, respectively. Care has been taken in calculating yearly–averaged current–sheet tilt angle and magnetic field values that correspond to the PAMELA spectra. Following this study where the numerical model was used to investigate the individual effects resulting from changes in the tilt angle, diffusion coefficients, and global drifts, it was found that all these modulation processes played significant roles in contributing to the total increase in CR intensities from 2006 to 2009, as was observed by PAMELA. Furthermore, the effect that drifts has on oppositely charged particles was also evident from the difference between the peak–shaped time profiles of protons and the flatter time profiles of electrons, as is expected for an A < 0 polarity cycle. Since protons, which drift into the heliosphere along the heliospheric current–sheet, haven’t yet reached maximum intensity levels by 2008, their intensities increased notably more than electrons toward the end of 2009. The time and energy dependence of the electron to proton ratios were also studied in order to further illustrate and quantify the effect of drifts during this remarkable solar minimum period.
Thesis (M.Sc. (Physics))--North-West University, Potchefstroom Campus, 2012.

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Dorociak, Petr. « Vliv polarizační disperze na chybovost optického kanálu ». Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2008. http://www.nusl.cz/ntk/nusl-217496.

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Master’s thesis engages in the impact of polarization mode dispersion on optical communication system. Polarization mode dispersion is mathematically described by Stoke’s and Jone’s space and ensure the theoretic causes of the rise of polarization mode dispersion that are divided on the external and internal effects. On the basis of these effects grow up a differential group delay (DGD) which makes causes that individual polarization modes have between them a time delay and limitation of maximum bit rate. Then master´s thesis analyses the influence of the polarization mode dispersion on the pulse enlargement and on the modulation signal. In this work, there are described the most applicated optical modulation formats. Polarization mode dispersion has also influence on the bit error rate of optical fibre link and closing of eye diagram too. Eye diagram is used to view the transmission characteristics and diagnoses the channel errors. Eye diagram is connected with the definitions as a bit error rate (BER) and signal-to-noise ratio (SNR) that are explained in this work too. Following the gained experiences it was designed an useful graphic interface to display the effect of the polarization mode dispersion on the transmitted signal. Realization of the graphic interface is created in the program MATLAB. In Matlab-Simulink are created six models according to the kind of modulations with characteristic AWGN (Additive White Gaussian Noise) channel. Program was tested for a typical values. In all calculations it is counted only with the losses that are caused by the polarization mode dispersion. It is not calculated with the losses that are caused by a chromatic dispersion and attenuation. At the end of this work are evaluated all types of modulation formats depending on the polarization mode dispersion, optical fibre length, price and complexity of the realization. Atteined results of my master’s thesis are compared with two foreign articles.

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Novaski, Silvia Mansur Scagliusi. « Envolvimento das celulas TTCR gama delta na fase de recuperação da encefalomielite experimental autoemune (EAE) induzida em ratos Lewis ». [s.n.], 1998. http://repositorio.unicamp.br/jspui/handle/REPOSIP/316939.

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Orientador: Leonilda Maria Barbosa dos Santos
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: A EAE é uma doença autoimune causada por linfócitos T CD4 +. Pode ser induzida em animais geneticamente susceptíveis através da imunização com mielina ou seus componentes, ou ser transferida passivamente para animais normais através de clones autorreativos aos componentes da mielina. É utilizada como modelo para o estudo da Esclerose Múltipla Humana. A EAE induzida em ratos Lewis é caracterizada por se apresentar como doença monofásica, isto é, após a inoculação com o neuroantígeno, o animal apresenta um único e severo pico da doença, se recupera e não volta mais a apresentar períodos de exacerbação. Vários autores têm demonstrado o envolvimento das células T TCR ?d, citocinas como o TGFß, e deleção dos clones autorreativos por apoptose no modelo de EAE. Desta forma, no presente trabalho demonstramos que as células T TCR ?d estão significativamente aumentadas no período de recuperação da doença e que esta população celular secreta TGF, citocina e também esta envolvida na recuperação da mesma por seu efeito regulador do sistema imune. Foi também demonstrado que a recuperação do animal é devido a deleção dos clones autorreativos por apoptose
Mestrado
Imunologia
Mestre em Ciências Biológicas

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Cruz, Estael Luzia Coelho Madeira da. « Avaliação de formulações de uso tópico a base de insulina no distúrbio das glândulas lacrimais e na regeneração da córnea em ratos diabéticos ». Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/60/60137/tde-30102014-141541/.

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Distúrbios na superfície da córnea e nas glândulas lacrimais acometem com frequência os indivíduos com diabetes mellitus. Atualmente não existe tratamento seguro e eficaz para feridas na córnea e o tratamento da síndrome do olho seco (SOS) é predominantemente sintomático. A administração tópica da insulina (INS) é uma estratégia promissora para tratar esses distúrbios, devido à presença de seus receptores na superfície ocular e na glândula lacrimal, e aos seus efeitos metabólicos e mitogênicos. No entanto, os fármacos aplicados topicamente na forma de solução são rapidamente drenados do olho, resultando em uma baixa biodisponibilidade local. O objetivo deste trabalho foi desenvolver formulações contendo INS e avaliar a sua influência no distúrbio das glândulas lacrimais e na regeneração da córnea em ratos diabéticos. Foram desenvolvidas quatro formulações contendo 1 UI/mL de INS: dispersão contendo insulina (DISP INS), dispersão contendo micropartículas quitosana/INS (DISP MP INS), gel termorreversível in situ com INS (Gel INS) e Gel contendo as micropartículas quitosana/INS (Gel MP INS). Também foram produzidas formulações \"brancas\", sem a veiculação do fármaco: dispersão contendo micropartículas sem insulina (DISP MP s/INS); gel termorreversível in situ sem insulina (Gel s/INS). As MP incorporadas nas formulações foram preparadas por spray drying e apresentaram tamanho de 4,0±0,1 ?m, morfologia adequada e grande quantidade de INS (77±6%). Todas as formulações apresentaram pH e osmolalidade compatíveis com o uso ocular. Durante o estudo in vivo, foi realizado o tratamento diário (15 dias) dos animais diabéticos, com as formulações (50 ?L) em ambos os olhos, exceto nos controles positivo (sem diabetes) e controle negativo (diabético não tratado). Todos os animais tratados com INS aumentaram a produção de fluido lacrimal, sendo que, ao término do tratamento, não foi observada diferença estatística entre o controle positivo e aqueles tratados com DISP INS e com Gel MP INS. A INS foi detectada na glândula lacrimal e no globo ocular dos animais tratados com DISP MP INS, Gel INS e Gel MP INS, sendo que a maior concentração de INS foi encontrada nos ratos tratados com Gel MP INS. Ao término do tratamento houve redução da glicemia dos animais tratados com a INS, o que pode sugerir um tratamento coadjuvante em pacientes diabéticos. Estudos de citologia de impressão mostraram que o Gel INS e Gel MP INS foram capazes de aumentar o número de células do epitélio da córnea e melhorar a relação núcleo/citoplasma em relação ao controle negativo. A histologia do globo ocular mostrou que essas duas formulações também melhoraram a espessura do epitélio da córnea, que foi semelhante a dos controles positivos. Conclui-se que a incorporação da INS nos géis e nas micropartículas desenvolvidas desempenhou um efeito positivo no tratamento da síndrome do olho seco e de lesões na córnea.
Disorders in the corneal surface and the lachrymal glands often affect individuals with diabetes mellitus. Nowadays there is no safe and effective treatment for wounds in the cornea and the treatment of dry eye syndrome (DES) is primarily symptomatic. Topical administration of insulin (INS) is a promising strategy for treating these disorders due to the presence of receptors on the ocular surface and lacrimal gland, besides its metabolic and mitogenic effects. However, the drugs applied topically in the form of a solution are quickly drained from the eye, resulting in a low local bioavailability. The aim of this study was to develop formulations containing INS and evaluate their influence on disorders of lacrimal glands and cornea healing in diabetic rats. Four formulations containing 1 IU/mL of INS were developed: dispersion containing insulin (DISP INS), dispersion containing chitosan microparticles/INS (DISP MP INS), in situ forming gel containing INS (Gel INS) and in situ forming gel containing microparticles chitosan/INS (Gel MP INS). \"White\" formulations were also produced without the drug: dispersion containing microparticles without insulin and in situ forming gel without insulin. MP incorporated in the formulations were prepared by spray drying and showed size of 4.0±0.1 ?m, proper morphology and high INS load (77±6%). All formulations exhibited pH and osmolarity compatible with the ocular use. In vivo studies were performed using diabetic rats that were treated daily (15 days) with instillation of the formulations (50 ?L) in both eyes, except in the positive controls (health rats) and negative control (untreated diabetic rats). All animals treated with INS showed an increase in the production of tear fluid. After treatment, no statistical difference was observed between the positive control and those treated with DISP INS and Gel MP INS. The INS was detected in the lacrimal gland of the animals treated with DISP MP INS, Gel INS and Gel MP INS, with the highest concentration of INS found in mice treated with Gel MP INS. After treatment there was a reduction in blood glucose of the animals treated with formulations containing INS, which suggests that developed formulations may be used as an adjuvant treatment in diabetic patients. Impression cytology studies showed that the Gel INS and Gel MP INS were able to increase the number of the corneal epithelium cells and improve nucleus/cytoplasm ratio compared to the negative control. The histology of the eyeball showed that these two formulations have improved the thickness of the corneal epithelium, which was similar to the positive controls. In conclusion, incorporation of INS in the gels and MP developed induced a positive effect in the treatment of dry eye syndrome and corneal wound.

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Laqui, Calizaya Fernando Ramiro. « Estimación de la erosión y transporte potencial de sedimentos hasta el eje de la futura represa Callazas en sub-cuenca del río Callazas en la región Tacna-Perú ». Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2019. http://hdl.handle.net/10757/626410.

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La investigación consiste en la estimación de la tasa potencial media de erosión hídrica (ton/ha. año) y el volumen promedio del transporte potencial de sedimentos en millones de metros cúbicos (MMC) en proyección a 50 años hasta el eje de la futura represa Callazas. La delimitación del área de estudio se ubica desde aguas abajo de la laguna Suches hasta el eje de la futura represa Callazas denominada subcuenca Callazas Zona 1. Se estima que la tasa de erosión hídrica promedio con la metodología de USLE a nivel conceptual es 108.9 (ton/ha. Año) y con herramienta GIS un valor de 64.3 (ton/ha. año), el cual se considera una erosión ligera/moderada. Asimismo, se estima el volumen de sedimentos del vaso proyectado de la represa Callazas con el valor de 0.372 MMC del registro histórico de 50 años con USLE y con la fórmula de transporte total de sedimentos de Englund-Hansen la estimación de 0.485 MMC en proyección a 50 años de operación. Por tanto, por un factor de seguridad de resultados se complementan las 2 metodologías con un volumen muerto de 0.857 MMC. El resultado preliminar se podría considerar aceptable ya que el estudio de factibilidad de la represa Callazas estima 11.5 MMC de volumen de almacenamiento y 1 MMC de volumen muerto, el cual resulta menor al volumen muerto proyectado.
The research consists in estimating the average potential rate of water erosion (ton / ha. Year) and the average volume of potential sediment transport in millions of cubic meters (MMC) in projection at 50 years to the axis of the future dam Callazas. The delimitation of the study area is located from downstream of the Suches lagoon to the axis of the future Callazas dam called Callazas sub-basin Zone 1. It is estimated that the average water erosion rate with the USLE methodology at the average conceptual level is 108.9 (ton / ha. year) and with GIS tool an average of 64.3 (ton / ha. year), which is considered a light / moderate erosion. Likewise, the volume of sediments of the projected vessel of the Callazas dam is estimated with the value of 0.372 MMC of the historical record of 50 years with USLE and with the formula of total transport of sediments of Englund-Hansen the estimate of 0.485 MMC in projection to 50 years of operation. Therefore, the 2 methodologies area complemented by a safety factor of results with a dead volume of 0.857 MMC. The preliminary result could be considered acceptable since the feasibility study of the Callazas dam estimates 11.5 MMC of storage volume and 1 MMC of dead volume, which is less than the projected dead volume.
Tesis

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Arvidsson, Emma. « Skiljer sig blinkfrekvensen vid läsning på olika medier ? » Thesis, Linnéuniversitetet, Institutionen för medicin och optometri (MEO), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-76021.

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Syfte: Syftet med den här studien var att undersöka om Spontaneous Eye Blink Rate (SEBR) skiljde sig åt vid läsning på utskrivet papper, surfplatta eller smartphone. Det jämfördes också huruvida fullständiga och ofullständiga blinkningar skiljde sig åt vid läsning på de olika medierna. Metod: Deltagarna (n=29) fick läsa tre olika texter på utskrivet papper, surfplatta och smartphone samtidigt som de filmades. I efterhand granskades samtliga videos två gånger för att räkna fullständiga blinkningar, ofullständiga blinkningar och totalt antal blinkningar (SEBR). Resultat: Den här studien visade att där finns en signifikant skillnad av totalt antal blinkningar vid läsning på utskrivet papper och surfplatta (p=0,03), där blinkningar/minut sjönk med 14,9% vid läsning på utskrivet papper, jämfört med surfplatta. För ofullständiga blinkningar fanns en statistiskt signifikant skillnad mellan utskrivet papper och surfplatta (p=0,02), där antalet ofullständiga blinkningar/minut ökade med 30,0% vid läsning på surfplatta, jämfört med utskrivet papper. Vid läsning på surfplatta och smartphone fanns en signifikant skillnad gällande ofullständiga blinkningar (p=0,01), där antalet ofullständiga blinkningar/minut ökade med 42% vid läsning på surfplattan, jämfört med smartphone. Slutsats: Spontaneous Eye Blink Rate skiljer sig vid läsning på papper och surfplatta. Ofullständiga blinkningar är flest vid läsning på surfplatta. Inga signifikanta skillnader finns mellan utskrivet papper och smartphone.
Purpose: The purpose of this study was to evaluate whether Spontaneous Eye Blink Rate (SEBR) differ when reading on hard copy, tablet or smartphone. Complete and incomplete blinks were also evaluated to see if there were any differences regarding the hard copy, tablet and smartphone. Methods: The participants read three different texts on hard copy, tablet and smartphone while they were being filmed. Afterwards, each video was analysed twice in order to count complete blinks, incomplete blinks and total blink rate (SEBR). Results: This study showed that there is a significant difference in total blink rate between reading on hard copy and tablet (p=0.03), where blinks/minute decreased by 14.9% for the hard copy condition. There was also a significant difference in incomplete blinks regarding the two devices (p=0.02), where incomplete blinks increased by 30.0% when reading on tablet. Tablet and smartphone reading also resulted in a significant difference, where incomplete blinks increased by 42% when reading on tablet (p=0.01). Conclusion: Spontaneous Eye Blink Rate differ when reading on hard copy and tablet. Incomplete blinks increase when reading on tablet. No significant differences are found between hard copy and smartphone.

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Ferreira, Pedro João Bem-Haja Gabriel. « Psychophysiology of eyewitness testimony ». Doctoral thesis, Universidade de Aveiro, 2018. http://hdl.handle.net/10773/22797.

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Doutoramento em Psicologia
As testemunhas oculares são muitas vezes o único meio que temos para aceder à autoria de um crime. Contudo, apesar dos 100 anos de evidência de erros no testemunho ocular, a consciência das suas limitações como meio de prova só ganhou força no advento do ADN. De facto os estudos de exoneração mostraram que 70 % das ilibações estavam associadas a erros de testemunho ocular. Estes erros têm um impacto social elevado principalmente os falsos positivos, por colocar inocentes na prisão. De acordo com a literatura, deverão ser utilizadas novas abordagens para tentar reduzir o numero de erros de identificação. Destas abordagens, destacam-se a análise dos padrões de movimentos oculares e os potenciais evocados. Nos nossos estudos utilizamos essas novas abordagens com o objetivo de examinar os padrões de acerto ou de identificação do criminoso, usando um paradigma de deteção de sinal. No que diz respeito aos movimentos oculares, não foram encontrados padrões robustos de acerto. No entanto, obtiveram-se evidências oculométricas de que a fusão de dois procedimentos (Alinhamento Simultâneo depois de um Alinhamento Sequencial com Regra de Paragem) aumenta a probabilidade de acerto. Em relação aos potenciais evocados, a P100 registou maior amplitude quando identificamos um inocente. Este efeito é concomitante com uma hiperactivação no córtex prefrontal ventromedial (CPFVM) identificada na análise de estimação de fontes. Esta hiperativação poderá estar relacionada com uma exacerbação emocional da informação proveniente da amígdala. A literatura relaciona a hiperativação no CPFVM com as falsas memorias, e estes resultados sugerem que a P100 poderá ser um promissor indicador de falsos positivos. Os resultados da N170 não nos permitem associar este componente ao acerto na identificação. Relativamente à P300, os resultados mostram uma maior amplitude deste componente quando identificamos corretamente um alvo, mas não diferiu significativamente de quando identificamos um inocente. Porém, a estimação de fontes mostrou que nessa janela temporal (300-600 ms) se verifica uma hipoativação dos Campos Oculares Frontais (COF) quando um distrator é identificado. Baixas ativações dos COF estão relacionadas com redução da eficiência de processamento e com a incapacidade para detetar alvos. Nas medidas periféricas, a eletromiografia facial mostrou que a maior ativação do corrugador e a menor ativação do zigomático são um bom indicador de quando estamos perante um criminoso. No que diz respeito ao ritmo cardíaco, a desaceleração esperada para os alvos devido à sua saliência emocional apenas foi obtida quando a visualização de um alvo foi acompanhada por um erro na identificação (i.e., um falso negativo). Neste trabalho de investigação parece que o sistema nervoso periférico está a responder corretamente, identificando o alvo, por ser emocionalmente mais saliente, enquanto que a modulação executiva efectuada pelo CPFVM conduz ao falso positivo. Os resultados obtidos são promissores e relevantes, principalmente quando o resultado de um erro poderá ser uma condenação indevida e, consequentemente, uma vida injustamente destruída.
Eyewitnesses are often the only way we can access the author of a crime. However, despite 100 years of evidence of errors in eyewitness testimony, awareness of its limitations only gained strength with the advent of DNA. In fact, 70% of exonerations have been associated with eyewitness errors. These errors have a high social impact, mainly false positives. According to the literature, new approaches to try to reduce the number of identification errors should be used. Of these, the study of oculometric patterns and event-related Potentials (ERP) stand out. In our studies, these new approaches were used with the objective of examining patterns of accuracy, using a signal detection paradigm. Regarding eye movements, no entirely clear patterns were found. However, there was oculometric evidence that the merging of two procedures (Simultaneous Lineup after a Sequential Lineup with Stopping Rule) increases performance accuracy. Regarding ERPs, the P100 registered a larger amplitude when an innocent was identified. This effect is concomitant with a hyperactivation in the ventromedial prefrontal cortex (VMPFC) identified by source estimation analysis. This hyperactivation might be related to an emotional exacerbation of the information coming from the amygdala. The literature relates the hyperactivation in the VMPFC with false memories, and these results suggest that the P100 component might be a promising marker of false positive errors. The results of the N170 do not allow to associate this component with accuracy. Regarding the P300, the results showed a greater amplitude of this component when a target was correctly identified but did not differ significantly from when an innocent was identified. However, source analysis in this time window (300-600 ms) showed a hypoactivation of Frontal Eye Fields (FEF) when a distractor was identified. FEF inactivations are related to the reduction of processing efficiency and to the inability to detect a target. Concerning the peripheral measures, facial electromyography showed that the greater activation of the corrugator and the lower activation of the zygomaticus are a good marker of when we are facing a perpetrator. Regarding heart rate, the expected deceleration for the targets due to their emotional salience was only obtained when the visualization of a target was accompanied by an error in the identification (i.e., a miss). In this research it seems that the peripheral nervous system is responding correctly, identifying the target, because it is emotionally more salient, while the executive modulation carried out by the VMPFC causes the false positive error. The results presently obtained are promising and relevant, especially when the result of an error might be an undue condemnation of an innocent and consequently a destroyed life.

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Silva, Marlon Richard Hilário da. « Efeitos de diferentes taxas de crescimento na recria sobre o desempenho, idade a puberdade e produção leiteira em fêmeas da raça Santa Inês ». Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/11/11139/tde-14122009-154229/.

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Experimento I: Foram utilizadas 60 borregas da raça Santa Inês com o objetivo de avaliar os efeitos de três taxas de crescimento até os 7 meses de idade. Os tratamentos foram delineados visando obter alta taxa de crescimento (ATC), moderada taxa de crescimento (MTC) e baixa taxa de crescimento (BTC). Foram avaliados o consumo de matéria seca, o ganho de peso corporal e as concentrações séricas de progesterona para a detecção da idade à puberdade. Foram verificados efeitos lineares (p<0,01) para o peso corporal e metabólico, sendo os maiores valores encontrados para os animais do tratamento ATC. Efeito linear (p<0,01) foi verificado para o ganho médio diário (GMD) sendo de 0,182; 0,156 e 0,136 kg/dia para os tratamentos ATC, MTC e BTC respectivamente. Borregas pertencentes ao tratamento ATC apresentaram maior conversão alimentar sendo os valores para o tratamento ATC de 6,1; MTC de 7,1 e BTC de 9,2 kg MS/ kg de ganho de peso. Verificou-se diferença (p<0,01) quanto a porcentagem de animais que atingiram a puberdade sendo o tratamento MTC com o maior número de borregas púberes até os 7 meses de idade (60%), seguida dos tratamentos ATC (45%) e BTC (15%)com peso médio de 39,3 kg de peso corporal, sendo 70% do peso adulto. Experimento II: As borregas utilizadas no experimento 1 com 37 Kg de PC entraram em estação de monta e após o parto receberam uma única dieta, sendo blocadas de acordo com o peso e dias de lactação. Observou-se efeito quadrático (p<0,01) na produção de leite em 3h (137,9; 150,1 e 104,4 g), efeito quadrático (p<0,05) para LCG (167,2; 178,9 e 129,4) e efeito quadrático (p<0,03) LCGP (216,5; 140,5 e 162,7). Os teores de gordura (9,8; 8,9 e 8,3%) e de proteína (4,2; 4,2 e 4,6 apresentaram efeitos lineares sendo (p=0,01) para gordura e (p<0,01) para proteína. Experimento III: Os objetivos deste experimento foram avaliar o efeito da inclusão de bagaço de cana-de-açúcar in natura (BIN) sobre o consumo e a digestibilidade aparente dos nutrientes, balanço de nitrogênio e os parâmetros ruminais de cordeiros Santa Inês. Quatro cordeiros providos de cânula ruminal com peso corporal (PC) médio inicial de 30kg foram alojados individualmente em gaiolas para ensaios de metabolismo. O tratamento controle positivo (CONT) consistia de uma ração de alto concentrado contendo de 10% de feno de coastcross (Cynodon sp.) na MS, sendo os demais tratamentos níveis crescentes de BIN em 10, 20 e 30% da MS, constituindo os tratamentos 10BC, 20BC e 30BC. As rações experimentais foram isonitrogenadas (13,75±0,25% PB). Não verificou-se efeito de tratamento (p>0,05) sobre o consumo de MS, MO, e PB em kg/dia e g/kg de PC 0,75; apenas sobre consumo de FDN com efeito linear (p< 0,01). O balanço de nitrogênio, assim como a concentração de acetato, propionato, butirato, concentração total de AGCC, amônia no fluido ruminal e a de digestibilidade aparente da MS, MO, PB e FDN não foram afetados pelos tratamentos.
Trial I: Sixty Santa Ines ewe lambs were used to evaluate the effects of three growing rates until 7 months of age. Treatments were defined to achieve high (HGR), moderate (MGR) and low (LGR) growing rates. The dry matter intake and average daily gain (ADG) were evaluated, well as serum levels of progesterone in order to detect the age of puberty. Linear effects (P<0.01) to body weight (BW) with values being 59.5, 61.4, and 58.0 to HGR, MGR and LGR, respectively. Linear effects (P<0.01) was also observed for average daily gain with values being 0.182, 0.156, and 0.136 kg/day, for HGR, MGR and LGR, respectively. The feed:gain ratio showed a linear effects (p<0.02) according to raw sugarcane bagasse inclusion in diet with values being 6.1, 7.1 (M) and 9.2 kgDM/kg BW for HGR, MGR and LGR, respectively. Linear effects (p<0.01) was observed for the percentage of animals of ewe lambs the reached puberty at 7 months of age, showing highest values for MGR (60%), followed by HGR (45%) and LGR (15%) treatment. Trial II: The same ewe lambs of Experiment 1 were bred at 37 kg of BW and after lambing they received a unique diet. The ewe lambs were blocked according to body weight and days in milking. According to the energy density increase in the diet, quadratic effects (p<0.01) was observed on milk production recorded in a 3-hour interval (137.9; 150.1 and 104.4 g), fat corrected milk (167.2, 178.9 and 129.4 g) and fat and protein corrected milk (216.5, 140.5, 162.7g). Fat (9.77, 8.92 and 8.35%) and protein (4.2, 4.2, and 4.6%) showed linear effects (P=0.01) for fat and (P<0.01) for protein. Trial III: The aim of this study was to evaluate the inclusion of raw sugarcane bagasse (RSB) on dry matter intake and apparent digestibility of nutrients, nitrogen balance and ruminal parameters of Santa Ines ram lambs. Four ruminally fistulated ram lambs averaging 30 kg of BW were placed in metabolism crates. The control treatment (CONT) consisted of a high concentrate diet with 10% of coastcross (Cynodon sp.) hay in the dietary DM and the others treatments consisted of 10, 20 and, 30% of RBS in the dietary DM. The diets were formulated to provide similar concentration of crude protein (13.75±0.25%). No effects were observed for DMI, OM, and CP in kg/day and g/kg of BW0.75. Linear effects (p<0.02) was observed for NDF intake according RBS inclusion. Variables, as well as total SCFA, acetate, propionate, and butyrate concentrations. Ruminal ammonia and apparent nutrient digestibility also did not differ among treatments.

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Vedegytė, Vaida. « Ūkio dydžio įtaka avių produktyvumui ». Master's thesis, Lithuanian Academic Libraries Network (LABT), 2014. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2014~D_20140618_233058-29401.

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Temos aktualumas. Avininkystė Lietuvoje yra svarbi žemės ūkio sritis. Šio sektoriaus plėtrai šalyje yra palankios gamtinės sąlygos, susiformavusios gyvulių auginimo tradicijos, sukaupta patirtis. Gyvulininkystės sektorius yra daugiašakė ir įvairiapuse produkcija pasižyminti veikla, reikšminga Lietuvos gyventojams daugeliu ekonominių ir socialinių aspektų. Šis sektorius yra reikšmingas, aprūpinant Lietuvos vartotojus įvairiais maisto produktais bei svarbus Lietuvos eksporto šaltinis. Gyvūninės kilmės produktai yra svarbi subalansuotos mitybos dalis. Juose yra daug žmogaus organizmui reikalingų maisto medžiagų, vitaminų ir mineralų. Lietuvos Respublikos žemės ūkis atlieka svarbią ekonominę, socialinę, gamtosauginę ir etnokultūrinę funkciją, todėl laikomas prioritetine ūkio šaka. Jis pajėgus aprūpinti šalies gyventojus visais kokybiškais maisto produktais ir dalį jų eksportuoti. Nors ir lėtai, avininkystės sektorius plečiasi. Auga mėsos paklausa, atsigauna ir vilnos bei kailių perdirbėjai. Vidutinis avių ūkis Lietuvoje, palyginti su vakarų šalimis, dar yra labai mažas. Dauguma augintojų laiko nedaug avių. O tų žmonių, kuriems avininkystė yra verslas, tėra vos kelios dešimtys. Tačiau mažieji augintojai pamažu didina savo bandas. Įdiegus pažangias intensyvaus avių auginimo technologijas, auginant perspektyvias krypties avių veisles, galima tikėtis šio verslo sėkmės. Darbo objektas: skirtingą skaičių avių turintys ūkiai. Darbo tikslas: išanalizuoti ūkio dydžio įtaką avių... [toliau žr. visą tekstą]
Relevance of the thesis. Shepherding has an important place in Lithuania‘s agriculture. There are suitable enviromental conditions, established cattle herding traditions and accumulated experience needed for this sector‘s further development in the country. The area of animal husbandry is activity known for its multisectoral and multifaceted production, many aspects of which has great economical and social significance for Lithuanians. This area is also very significant when providing Lithuanian consumer with eatables, furthermore it is very important branch of Lithuania‘s export. Products of animal origin takes big part in a balanced diet. They contain many components, vitamins and minerals which human body requires daily. Husbandry has important economical, social, enviromental and ethnocultural function in the Republic of Lithuania, thus it has priority in Lithuania‘s economy. It has capability not only to provide quality eatables for citizens, but also to export some. Sheepherding sector is growing, even though the growth rate is not very pronounced. The demand for meat grows; wool and fur processors are recovering. In Lithuania average sheep farm is very small when comparing with farms in other western countries. Most livestock owners don‘t have a lot of sheep. Furthermore, there are only few who make business out of it. However the small farmers seem to be increasing their flocks. If this business were introduced to advanced sheep herding technologies as well as... [to full text]

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Behrami, Drilon. « Maskulinitet, ras och identitet i J. Coles studioalbum 4 Your Eyez Only : Nutidshistoria, kollektivt minne och intersektionalitet i samtida hiphopmusik ». Thesis, Linnéuniversitetet, Institutionen för kulturvetenskaper (KV), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-97930.

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This study examines intersectionality and identity in rapper Jermaine Lamarr Cole’s studio album 4 Your Eyez Only. Through discourse analysis, the essay studies the representation of aspects of identity in the album, with a focus on gender, race, class and sexuality. The study also examines prosthetic memory in the album, with the intention of finding correlating narratives that create a general concensus of how society is viewed from marginalised groups in the US. The findings conclude that gender, race and class are expressed as the main buildingblocks for a characters identity in the album. It is telling that sexuality remains untouched in this regard. The reader is exclusively exposed to the normative heterosexual perspective, completely ignoring any notion of varied sexual orientations. Furthermore the findings conclude that J. Cole showcases a generally negative view on the govornment, as it is percieved as one of many instances keeping marginalised groups at the bottom of a societal foodchain

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SANCHEZ, ANDREA. « Projeto e confecção de simuladores oftálmicos para aplicações clínicas ». reponame:Repositório Institucional do IPEN, 2006. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11431.

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Made available in DSpace on 2014-10-09T12:51:51Z (GMT). No. of bitstreams: 0
Made available in DSpace on 2014-10-09T14:06:32Z (GMT). No. of bitstreams: 0
Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

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Horský, Tomáš. « Rozšíření optického vláknového přenosového systému ». Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2021. http://www.nusl.cz/ntk/nusl-442378.

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The diploma thesis describes the elaboration of a program for the simulation of an optical transmission path. The work introduces the basic parameters of optical transmission, such as attenuation, dispersion and bandwidth. Furthermore, the techniques of line code and error detection are described in the work, especially a cyclic redundancy sum. The key parameter of this thesis is dispersion of the optical signal. The work includes the characteristics of the eye diagram and its analysis. The resulting program can also be used to measure the real transmission route and its parameters.

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Thèses sur le sujet « Eye Rats »

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