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Tesi sul tema "Efferent"

Autore: Grafiati

Pubblicato: 4 giugno 2021

Ultima modifica: 12 febbraio 2022

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1

Garinis, Angela. "Efferent Control of the Human Auditory System". Diss., The University of Arizona, 2008. http://hdl.handle.net/10150/195850.

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The effects of auditory efferent activity on peripheral physiology may be examined by presenting broadband noise (BBN) to the contralateral ear during otoacoustic emission (OAE) recordings. The presentation of BBN typically produces a reduction of OAE amplitudes in comparison to a condition without BBN. This is termed contralateral suppression. Limited information exists regarding the effects of contralateral BBN on responses observed at higher levels in the auditory system. The present study employed this paradigm to investigate interactions of attention and laterality on the transient evoked otoacoustic emission (TEOAE), auditory brainstem response (ABR) and cortical auditory evoked potentials (CAEP) P1-N1-P2. TEOAEs were evoked by 60 dB SPL clicks; ABRs and CAEPs were evoked by 60 dB SPL 2.0 kHz tone pips in 15 normally hearing adults. Four conditions were employed for each ear: 1) quiet (no noise); 2) 60 dB SPL contralateral BBN; 3) words (at -3 dB SNR) embedded in 60 dB SPL contralateral BBN while subjects classified words as animal versus food items; 4) words from condition #3 played backwards and embedded in 60 dB SPL contralateral BBN. For TEOAEs: 1) more suppression was evident in the active attention condition than the passive listening conditions and 2) right ear OAE amplitudes for the 8-18 ms time period exhibited more suppression in the presence of BBN for all noise conditions, although this did not meet statistical significance. For the ABR experiment, amplitudes in the noise conditions decreased in all epochs for the right ear, but not for the left. For the CAEP experiment, asymmetries were evident in temporal regions and an effect of contralateral noise was evident. The outcome of this investigation suggests that efferent activation by noise and active attention has diverse modulatory effects on electroacoustic and electrophysiologic responses along the auditory pathway.

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2

Sutcliffe, Louise Kathleen. "Chemical genetic dissection of efferent IRE1α signalling". Thesis, Durham University, 2012. http://etheses.dur.ac.uk/5943/.

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The Endoplasmic Reticulum is the cellular organelle primarily responsible for producing proteins on the secretory pathway, a pathway important in the production of biopharmaceuticals. One of the requirements for the successful production of a functional protein is correct folding of the polypeptide sequence. During conditions such as viral infection, mutant protein expression and cell differentiation the endoplasmic reticulum is placed under conditions of stress. IRE1 is a protein kinase and endoribonuclease, which along with PERK and ATF6, forms part of the Unfolded Protein Response, the system by which the cell deals with the stress caused by a high protein load. IRE1 is capable of increasing the protein folding capacity of the ER, by upregulating chaperone proteins and reducing the load by attenuating translation, (protective response). This action is mediated by splicing of the mRNA coding for the bZIP transcription factor XBP-1. IRE1 is also capable of causing apoptotic responses via TRAF2 (cell injuring response) resulting in the activation of JNK and NFκB. In this study, using site directed mutagenesis a panel of IRE1 mutants was produced and screened for alterations to the protective and cell injuring responses. Of these the D711A mutant was shown in mouse embryonic fibroblasts to retain endoribonuclease activity, and to display an attenuated cell injuring response. When this mutant was applied to an industrial CHO cell line it appeared to exhibit an increase in biopharmaceutical productivity over the wild type IRE1, indicating its potential for use in the biopharmaceutical cell lines.

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3

Ferry, Robert Thomas. "Auditory Processing and the Medial Olivocochlear Efferent System". Thesis, University of Essex, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.495573.

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The aim of this thesis is to investigate the role of the medial olivocochlear (MaC) efferent system in auditory processing. This was achieved by 'upgradi~g' an existing computer model of the mammalian auditory periphery (Meddis, 2006) to include the effect of stimulating the MaC system. The improved model (Ferry and Meddis, 2007) was evaluated against published physiological data including the responses of the basilar membrane, auditory nerve, and compound action potential. In all cases the model was able to replicate the basic effects ofMaC stimulation at each stage of the auditory periphery as demonstrated physiologically. The model was then used to investigate the suggestion that the MaC system is involved in improving the discriminability of transient sounds such as speech in noise. An improvement in the model auditory nerve response to speech when presented in noise was demonstrated as a result of MaC stimulation. This improvement was then quantified using a series of automatic speech recognition experiments. These experiments demonstrated that MaC stimulation in the model could be used to increase speech recognition performance at all signal-to-noise ratios tested. The temporal effect (or 'overshoot' phenomenon) was then used to characterise the time course of the MaC system psychoacoustically, and also to investigate the role of the MaC system in this phenomenon. The time course measured is in agreement with both temporal effect and MaC system literature and this time course will be added to the model at a future date. The temporal effect was demonstrated in the model only when MaC stimulation is used. This is consistent with the suggestion that the MaC system is an underlying mechanism of the temporal effect phenomenon. The model is proposed as a platform with which it possible to study the complex effects ofMaC stimulation in auditory perception.

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4

Simon, Horst Hubertus. "Development of the efferent system in the segmented chick brainstem". Thesis, King's College London (University of London), 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307096.

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5

MANIERE, CHRISTOPHE. "Acouphenes et exploration fonctionnelle du systeme efferent olivo-cochleaire median". Besançon, 1994. http://www.theses.fr/1994BESA3018.

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6

Fletcher, Mark. "Perceptual correlates of efferent modulation in the human auditory system". Thesis, University of Nottingham, 2015. http://eprints.nottingham.ac.uk/28915/.

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Elicitation of the medial olivocochlear reflex (MOCR) causes a reduction in the amount of gain (amplification) applied by the cochlear amplifier. This gain-control function is thought to play an important role in speech-in-noise perception. Otoacoustic emissions (OAEs) offer a qualitative measure of the effect of the MOCR on cochlear gain, but a quantitative measure is lacking. The aim of this thesis was to test whether any of the putative perceptual correlates of MOCR-induced cochlear gain reduction might provide such a measure. The first study (Chapter 2) is concerned with the mechanism of the overshoot effect, in which a brief signal presented at the onset of a masker is harder to detect when the masker is preceded by silence than when it is preceded by a “precursor” sound. It has been suggested that, in overshoot, the precursor might reduce cochlear gain by eliciting the MOCR and thereby cause a reduction in suppressive masking of the signal (adaptation of suppression). Overshoot, suppression, and adaptation of suppression were measured in the same participants. While the precursor yielded strong overshoot, and the masker produced strong suppression, the precursor did not appear to cause any adaptation of suppression. Predictions based on an established model of the cochlear input-output function indicate that the failure to obtain any adaptation of suppression is unlikely to represent a false negative outcome. It is argued that overshoot may be due to higher-order perceptual factors such as transient masking or attentional diversion. Overshoot was therefore not pursued as a quantitative measure of the MOCR. The second study (Chapter 3) aimed to develop a quantitative measure of the MOCR by modifying the established temporal masking curve (TMC) method for estimating cochlear gain psychophysically. The TMC method involves measuring the lowest masker level needed to just render inaudible a weak signal as a function of the temporal gap between the masker and signal. Here, the masker’s duration was shortened so that the masker would not itself elicit the MOCR in time to affect the signal’s audibility. A new way of estimating cochlear gain from TMC data by fitting the entire data set with a generic model of the cochlear response function was also developed. Using this approach, the effect on cochlear gain of a broadband-noise elicitor presented to the contralateral ear was measured. The TMCs suggest that the elicitor reduced cochlear gain by 4 dB, on average. OAE suppression measurements in the same participants suggested that this gain reduction was mediated by the MOCR. The approach developed in this chapter provides a quantitative estimate of MOCR-induced cochlear-gain reduction caused by a contralateral elicitor. The third study (Chapter 4) aimed to assess the validity of recent findings by Yasin et al. (2014), who reported an MOCR-induced cochlear-gain reduction by an ipsilateral elicitor that was four times larger than that found in the second study using a contralateral elicitor. Yasin et al. (2014) estimated cochlear gain reduction using the fixed-duration masking curve (FDMC) method, which is similar to the TMC method used in Chapter 3. In Chapter 4, the FDMC method was used to estimate the amount of gain reduction caused by a long ipsilateral elicitor, like the one used by Yasin et al. (2014). This was compared to the amount of gain reduction caused by a much shorter ipsilateral elicitor, which was presented at a level that produced the same amount of masking of the signal as the long elicitor, but was too short to have activated the MOCR in time to affect the signal detectability. The long and short elicitors both caused large psychophysical effects, indicating either that the MOCR acts more quickly than previously thought, or that the effect was not due to MOCR-induced cochlear gain reduction. OAE suppression was also found for both the long and short elicitors. It is argued that both the OAE and psychophysical effects of the short and long elicitors may, at least in part, be the result of nonlinear interactions between the elicitor and the masker resulting from direct temporal overlap of their cochlear responses. This thesis provides evidence against the idea that MOCR-induced cochlear-gain reduction plays a major role in either overshoot or in a recently reported large psychophysical masking effect by an ipsilateral noise, both of which have previously been attributed to the MOCR. This thesis has also contributed towards the refinement of an approach for quantitatively measuring cochlear gain and MOCR-induced cochlear gain reduction by a contralateral noise. In future, this approach could become a valuable audiometric profiling tool, and may give insight into the individual differences that underlie hearing problems in audiometrically normal listeners. Parametric exploration of the MOCR using this approach may also allow the functional importance of the MOCR in humans to be better understood.

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7

Ahmadi, Seyedeh Mahnaz. "CENTRAL VERSUS MONOTIC MASKING IN NON-SIMULTANEOUS MASKING CONDITIONS". The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1268166584.

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8

Shepherd, Iain Thomas. "The early development of the tectal efferent projection in the chick". Thesis, University of Oxford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.359514.

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9

Hill, Jennifer Clare. "The relationship between auditory efferent function and frequency selectivity in man". Thesis, University College London (University of London), 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.313735.

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10

Mahmood, Sally L. "The effect of the menstrual cycle on evoked otoacoustic efferent suppression". College Park, Md. : University of Maryland, 2008. http://hdl.handle.net/1903/8148.

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Thesis (Au.D.) -- University of Maryland, College Park, 2008.
Thesis research directed by: Dept. of Hearing and Speech Sciences. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.

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11

Welch, David 1968. "Investigation of the function of the olivocochlear efferent nerve pathway in humans". Thesis, University of Auckland, 2003. http://hdl.handle.net/2292/6032.

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The cochlea transduces sound into neural information. An important part of this transduction is an active process whereby the passive resonant characteristics are enhanced, leading to greater sensitivity and frequency selectivity. A population of sensory cells, called the outer hair cells, are the primary effectors of the active process, and can alter their length and stiffness dynamically. The outer hair cells are also innervated by the efferent nerve pathway descending from the region of the brainstem surrounding the medial portion of the superior olivary complex, and called the medial olivocochlear pathway. Previous research has demonstrated that activation of this pathway is associated with changes in cochlear micromechanics, and changes in the output measured at the auditory nerve. The pathway innervating one ear can be stimulated by presentation of sound to the contralateral ear. The roles of these pathways in hearing are not understood. The present research has investigated the perceptual effects of different levels of efferent activation in human subjects. Adaptive psychophysical procedures were used to investigate the change in monaural detectability of signals (broadband, high frequency, and low frequency noise; and 1-kHz tones, 7-kHz tones, and 100-µs clicks embedded in background noise) under a range of contralateral noise stimulation (from none to 80 dB SPL). Additionally, transient otoacoustic emissions were measured under the same range of contralateral stimuli, to confirm cochlear physiological changes. Auditory evoked potentials in response to a click, embedded in noise, were recorded from scalp electrodes, in order to confirm that the output of the cochlea was altered. A decrease in the detectability of all the noise stimuli, and click and 1-kHz tone signals embedded in background noise with increasing efferent activation was observed. The function relating change in detectability of the 7- kHz tone in noise to level of contralateral stimulation was U-shaped, suggesting that detectability was improved by middle levels of contralateral stimulation. Otoacoustic emission amplitudes were reduced by contralateral noise at the same levels at which the changes in detectability occurred. The amplitude and latency of the first wave of the auditory brainstem response were reduced with increasing olivocochlear pathway activation. It was reasoned that these effects resulted from suppression of the function of active processes within the cochlea by the activity of the olivocochlear pathway. In all cases, this produced a monotonic decrease in detectability of the signals, except for the 7-kHz tone in noise. The explanation for this finding was that the 7-kHz tone would have been more strongly masked by the broadband noise than either the 1-kHz tone or the click because of the upward spread of masking. Thus, suppression of activity in response to the noise would have improved the detectability of the tone under middle levels of efferent activity.

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12

Lukashkin, Andrei Nikolaevich. "Measurement and theory of cochlear non-linearity : mechanoelectrical transduction and efferent control". Thesis, University of Sussex, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285109.

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13

Holmes, Preston H. "The afferent and efferent connections of the telencephalon in the Senegal Bichir /". Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2001. http://wwwlib.umi.com/cr/ucsd/fullcit?p3022223.

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14

Darrow, Keith N. (Keith Noble). "Role of the lateral olivocochlear efferent system in hearing : selective lesioning studies". Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/37977.

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Thesis (Ph. D.)--Harvard-MIT Division of Health Sciences and Technology, 2006.
Includes bibliographical references (leaves 62-68).
Sensory cells and afferent auditory neurons in the cochlea receive efferent feedback via olivocochlear (OC) neurons originating in the brainstem's olivary complex. The OC system comprises 1) medial (M)OC neurons that decrease electromotility in outer hair cells, and 2) lateral (L)OC neurons that elicit slow excitation or inhibition of auditory nerve dendrites that contact inner hair cells. We investigated the organization and function of the LOC system by immunohistochemical and physiological studies in mice with unilateral stereotaxic destruction of LOC cell bodies. Double immunostaining in control cochleas and brainstems revealed two cytochemical subgroups of LOC neurons: a majority cholinergic population and a minority dopaminergic population. The observation of two LOC subgroups is consistent with reports that LOC activation can either excite or inhibit auditory nerve activity. In lesioned mice, we observed two physiological abnormalities. First, ipsilateral ears were more vulnerable to noise-induced auditory nerve dysfunction, consistent with speculation that dopaminergic transmission controls glutamate excitotoxicity of auditory nerve dendrites after acoustic overexposure.
(cont.) Second, ipsilateral auditory nerve responses were increased while contralateral responses were decreased, and the normal tight correlation of neural excitability between the two ears was disrupted. A neural circuit is proposed to explain bilateral effects from unilateral LOC innervation. We suggest that a key LOC function is to bilaterally balance ascending inputs to olivary complex neurons, which are responsible for computing sound location based on the interaural level differences coded in the response rates of auditory nerve fibers.
by Keith N. Darrow.
Ph.D.

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15

Gamze, Poyraz. "Läsning som estetisk upplevelse eller inhämtning av fakta : En studie om undervisningsmetoder i skönlitteratur för grundskolans mellanår". Thesis, Södertörns högskola, Lärarutbildningen, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-31639.

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The purpose of this study is to get an insight into how fiction tutoring in Swedish can be practised and how the reading is encouraged. A teacher can through her working methods control how the pupils relate to fiction and has therefor an important role, because of this the subordinate purpose of this study is to problematize and highlight how the teacher can encourage her pupils into different styles of reading. Questions:•What didactic choices does the teacher make in literature teaching?•What does the teacher want the pupils to pay attention to? •What are the learning methods for the pupils? This study has been made through observations and interviews with teachers who teach in primary school in Sweden. The empirical data have been analyzed based on Rosenblatt’s reading concepts and Langer’s conceptual worlds and furthermore their view of literature teaching and the teacher's role in it. The study shows that all of the teachers combine reading with writing assignments, where linguistic approaches are most common and usually primary. Even though the teachers showed an awareness of the importance of an aesthetic reading, they did not support aesthetic reading in their lessons. In the observed lesson it was shown that the method used by the teachers stimulated phase one in the imaginary worlds and an efferent reading which both pay attention for the impersonal and the general aspects that can be verified in a text. It should be noted that this study had a teacher’s perspective and not the perspective of the pupils.

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16

Beilin, Silvia Adriana. "Physiological effects of proctolin, octopamine and serotonin in a ventilatory muscle of the crayfish second maxilla". Thesis, McGill University, 1988. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=64099.

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17

Leijon, Sara. "Molecular characterization of cholinergic vestibular and olivocochlear efferent neurons in the rodent brainstem". Thesis, Linköping University, Department of Physics, Chemistry and Biology, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-56844.

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The neural code from the inner ear to the brain is dynamically controlled by central nervous efferent feedback to the audio-vestibular epithelium. Although such efference provides the basis for a cognitive control of our hearing and balance, we know surprisingly little about this feedback system. This project has investigated the applicability of a transgenic mouse model, expressing a fluorescent protein under the choline-acetyltransferase (ChAT) promoter, for targeting the cholinergic audio-vestibular efferent neurons in the brainstem. It was found that the mouse model is useful for targeting the vestibular efferents, which are fluorescent, but not the auditory efferents, which are not highlighted. This model enables, for the first time, physiological studies of the vestibular efferent neurons and their synaptic inputs. We next assessed the expression of the potassium channel family Kv4, known to generate transient potassium currents upon depolarization. Such potassium currents are found in auditory efferent neurons, but it is not known whether Kv4 subunits are expressed in these neurons. Moreover, it is not known if Kv4 is present and has a function in the vestibular efferent neurons. Double labelling with anti-ChAT and anti-Kv4.2 or Kv4.3 demonstrates that the Kv4.3 subunits are abundantly expressed in audio-vestibular efferents, thus indicating that this subunit is a large contributor to the excitability and firing properties of the auditory efferent neurons, and most probably also for the vestibular efferent neurons. In addition, we also unexpectedly found a strong expression of Kv4.3 in principal cells of the superior olive, the neurons which are important for sound localization.

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18

Lilaonitkul, Watjana 1975. "Frequency specificity of the ipsilateral, contralateral and binaural medical efferent reflexes in humans". Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/87179.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2002.
Includes bibliographical references (leaves 41-45).
by Watjana Lilaonitkul.
S.M.

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19

Vanderlaan, Gary. "Differential roles for hedgehog signaling in motor neuron development". Diss., Columbia, Mo. : University of Missouri-Columbia, 2006. http://hdl.handle.net/10355/4461.

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Thesis (Ph.D.)--University of Missouri-Columbia, 2006.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on April 29, 2009) Vita. Includes bibliographical references.

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20

Lima, da Costa Deise Mara. "Activité de base globale du nerf auditif, système olivocochléaire efferent médian et effets des aminosides". Bordeaux 2, 1997. http://www.theses.fr/1997BOR28469.

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21

Mertes, Ian Benjamin. "Repeatability of medial olivocochlear efferent effects on transient-evoked otoacoustic emissions in normal-hearing adults". Diss., University of Iowa, 2014. https://ir.uiowa.edu/etd/1364.

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The medial olivocochlear reflex (MOCR) is a brainstem-mediated reflex that reduces cochlear amplifier gain when elicited by sound. The MOCR may provide benefits such as protection from acoustic trauma and improved hearing in background noise. Measurement of MOCR effects may also have clinical applications. MOCR effects can be measured using transient-evoked otoacoustic emissions (TEOAEs), as amplitudes of TEOAEs are typically reduced during MOCR activation. The primary purpose of the current study was to quantify the repeatability of MOCR effects on TEOAEs because high repeatability in a healthy population is a necessary (but not sufficient) component of a clinically-useful test. A secondary purpose was to assess the relationship between MOCR strength and speech perception in noise. Twenty-one normal hearing subjects ages 18-30 participated. TEOAEs were elicited using 35 dB sensation level (SL) clicks. The MOCR was elicited using contralateral acoustic stimulation (CAS) consisting of 35 dB SL broadband noise. Sixteen measurements were made across a 5-week period (4 visits × 4 measurements per visit). TEOAEs were bandpass filtered in 1/6-octaves from 1-2 kHz. An individualized time-frequency analysis was used to select the largest TEOAE envelope peak within a restricted time analysis window. Responses were characterized as the complex ratio of TEOAEs obtained with versus without CAS. The statistical significance of effects was assessed. Results revealed generally high levels of stability across time, as assessed by the interquartile ranges of all results and as assessed by Cronbach's alpha. Four MOCR measurements appeared to be adequate to obtain a reliable baseline measurement. Individualized time-frequency analyses were also important for obtaining reliable measurements. However, several subjects showed stable baseline measurements but unusual patterns of variability at subsequent sessions. These changes did not appear to be the result of changes in auditory status, methodological issues, or equipment issues. No significant relationship was found between MOCR strength and speech perception in noise. Results suggest that MOCR measurements are stable in most subjects when using careful measurement and analysis methods, but that further work is needed to better characterize changes in MOCR and to validate the current methodology in a larger number of subjects.

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22

Karhumaa, P. (Pepe). "Carbonic anhydrases in the reproductive system:with special emphasis on isoenzymes VI, IX, XII, and a novel nuclear nonclassical form". Doctoral thesis, University of Oulu, 2002. http://urn.fi/urn:isbn:9514266641.

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Abstract Carbonic anhydrases (CAs) are a group of zinc-containing metalloenzymes that catalyze the interconversion of carbon dioxide and bicarbonate (CO2 + H2O ⇔ HCO3- + H+). They are present in almost all organs and are implicated in various biological functions, the most important of which is participation in the regulation of ion, water, and acid-base balance. Recently, some members of the CA gene family have been suggested to promote cell proliferation and to act as trophic growth factors. The present study was undertaken to examine the distribution of CA isoenzymes in the reproductive system, to attain a more detailed view on their linkage to the reproductive processes and to neonatal development. The expression of membrane-bound CA IX and CA XII was studied in the female and male reproductive tracts by immunohistochemistry and western blotting. CA XII was found to be expressed in the basolateral plasma membrane of luminal and glandular epithelia in human uterus. In human efferent ducts, it was located in the basolateral plasma membrane of luminal epithelium, where it coexpressed with Aquaporin-1. In epididymal duct, CA XII was only expressed in occasional epithelial cells. These cells coexpressed CA II, suggesting that they represent apical mitochondria-rich cells (AMRC). CA IX was also expressed in the basolateral plasma membrane of luminal epithelium in human efferent ducts, but its expression was not uniform among the tubules. These findings suggest that basolateral plasma membrane-associated CA IX and CA XII contribute, along with CA II and CA IV, to the regulation of acid-base balance and water transport in the reproductive tract. Western blotting of rat Leydig tumor cells and testis for CA II revealed an unidentified 66-kDa polypeptide band. The polypeptide was successfully purified from several rat tissues using CA inhibitor affinity chromatography. The amino acid sequence of the polypeptide showed it to be identical to NonO/p54nrb, a non-POU domain-containing octamer-binding protein previously implicated in transcriptional regulation. The recombinant NonO/p54nrb was shown to display CA activity, and the antibody to it predominantly immunostained the nuclei in lymphocytes, where CA activity was also detected histochemically. Accordingly, the nuclear Leydig cell CA immunoreactivity represents NonO/p54nrb. It is classified as a novel, nonclassical CA, and it may participate in pH-related events in the nucleus. Human and rat milk was found to contain CA VI by immunohistochemistry and western blotting. The enzyme purified from human milk by CA inhibitor affinity chromatography was confirmed by PNGase F digestion and amino acid sequence as CA VI. The CA VI concentrations in human colostral milk were approximately eight times higher than those in mature milk (34.7 mg/l vs. 4.5 mg/l). Secretion of CA VI into milk is suggested by its localization in the alveolar epithelium of the rat mammary gland. The structural and functional stability of CA VI in an acidic milieu, its suggested growth-supporting function in taste bud stem cells, and its high concentration in colostrum suggest that it is an essential factor for the growth and development of the newborn alimentary canal.

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23

Karlsson, Mattias O. "Genomleva eller genomlida? : En didaktisk studie av gymnasieelevers upplevelser av litteraturläsning och litteraturundervisning". Thesis, Högskolan för lärande och kommunikation, Högskolan i Jönköping, HLK, Sektionen för språk, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-17884.

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Denna studie syftar till att undersöka hur gymnasieelever upplever litteraturläsning samt i vilken utsträckning estetiska läsningar görs. Vidare undersöks hur litteraturläsningens potentiella pedagogisk-didaktiska funktioner uppnås och/eller utnyttjas. Data har samlats in genom en enkät med öppna och slutna frågor. Genom diskursanalys har respondenternas svar kategoriserats och kommenterats. Resultatet visar att eleverna både genomlider och genomlever undervisningen och läsningen. Andelen estetiska läsningar är låg jämfört med andelen efferenta. En grupp respondenter signalerar att de inte kan skapa någon mening i och av sin läsning alls och det finns respondenter som gör uttalat efferenta läsningar och som därvid lyckas sämre med att skapa mening: dessa genomlider således. Det finns tecken på goda estetiska läsningar i respondentgruppen som ett resultat av ett genomlevande av litteraturen. Dessa läsningar lyfts sällan fram som bas för kunskapsutvecklande samtal kring läsning vilket sannolikt skulle gynna den förra gruppen respondenter. Studien visar även att vissa respondenters läsningsförmåga är svag och denna primärt behöver stärkas. Studien visar på en relativt svag uppfattning kring litteraturläsningens syfte: från disciplinär åtgärd via språkriktighet till insikt om den egna individen. Det finns utrymme för att öka litteraturläsningens didaktiska funktioner och positiva effekter på kunskaps- och personlighetsutveckling. Studien visar att detta kan uppnås genom att främja läsningsförmågan hos efferenta och allmänt svaga läsare genom en förstärkning av uppfattningen av litteraturläsningens syften, uppdelning mellan litteraturhistoria och utveckling av läsningsförmåga, stärkt stöd före och efter läsningen, gemensam läsning och bok- och textsamtal. Formativ bedömning skulle stärka individuella insatser i förmågansutvecklingen samt höja den kvalitativa nivån på elevernas läsningar.

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24

Ramadan, Mohamed R. M. "Effect of distension of the urinary bladder on activity in efferent vagal and renal nerve fibres". Thesis, University of Leeds, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.235641.

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25

Grant, Lisa. "The role of ryanodine receptors and transient efferent innervation in cochlear inner hair cell afferent transmission". Thesis, University of Bristol, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.424421.

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26

Walters, G. E. "An electrophysiological study of the effects of stimulation of left atrial receptors on efferent vagal nerve fibres". Thesis, University of Leeds, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.378839.

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27

Mishra, Srikanta Kumar. "Otoacoustic emission (OAE)-based measurement of the functioning of the human cochlea and the efferent auditory system". Thesis, University of Southampton, 2010. https://eprints.soton.ac.uk/158633/.

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The discovery of otoacoustic emissions (OAE) has advanced our understanding of cochlear mechanics and the efferent auditory system. OAE are sounds generated within normal cochlea either spontaneously or in response to stimulation. The ability to measure OAE non-invasively, objectively and quickly makes a powerful tool to probe cochlear mechanics. Stimulation of the efferent auditory system causes changes in cochlear amplification processes and hence changes characteristics of OAE. Contralateral acoustic stimulation, commonly called OAE suppression, provides an index of the efferent auditory system (specifically, medial olivocochlear bundle) functioning. OAE is also a sensitive tool to demonstrate subtle changes in cochlear functioning caused by various pathological (e.g., noise exposure, aspirin toxicity, etc.) and non-pathological (e.g.,posture, efferent stimulation) factors. Although OAE are frequently used in both clinic and laboratory, their generation mechanism was not clearly understood until recently. It is currently accepted that distortion product otoacoustic emissions (DPOAE) are composed of two separate components, named wave- and place-fixed emissions. They not only arise from two different cochlear locations but also from two fundamentally different processes. Wave-fixed components arise from distortion sources and manifest a phase that is almost independent of frequency, where as, place-fixed components arise from reflection sources and have a phase that increases systematically with frequency. The overall aim of the work presented in this thesis was to use various OAE methods to examine cochlear function and the efferent auditory system. A related objective was to substantiate the functional relevance of the efferent auditory system in speech-in-noise perception, in order to address the clinical significance of measuring OAE suppression. Cochlear functioning was potentially manipulated by three treatments separately: one extrinsic (electromagnetic radiation exposure from mobile phone) and two intrinsic (posture and efferent activation). Potential changes in auditory function due to mobile phone exposure were evaluated in a within-subject study in a double-blind design (n=35).A comprehensive examination of the auditory system was conducted using audiometry,OAE and auditory event related potentials (ERP). The second experiment used mechanism-based DPOAE to investigate posture-induced changes in cochlear functioning (n=15). Similar DPOAE measurements were performed to evaluate the effect of contralateral acoustic stimulation on cochlear functioning (n=14). The last experiment examined the relationship between contralateral suppression of transient evoked otoacoustic emissions (TEOAE) and recognition of speech in noise (n=13). Results indicate that (i) acute exposure to mobile phone radiation does not cause any significant changes in auditory functions measured by TEOAE suppression, DPOAE or ERP (however, there were changes in auditory thresholds at 6 and 8 kHz), (ii) posture induced cochlear changes and contralateral acoustic stimulation cause significantly greater reduction in place-fixed components than wave-fixed components, and (iii) the efferent auditory system plays an anti-masking role in speech-in-noise recognition. It appears that wave- and place-fixed components are differentiallysensitive to changes in cochlear functioning. Collectively, the present results provide emerging empirical support for the need to separate the wave- and place-fixed components in DPOAE measurements. Because of inherent differences in the generation of wave- and place-fixed components, it is suggested that the separation of the components may improve the efficiency of DPOAE-based measures of cochlear dysfunction and also, of the efferent auditory system function.

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28

Meyers, Erin Elizabeth. "Afferent vs. efferent cervical vagal nerve stimulation: effects on blood glucose, insulin, and glucagon concentrations in rats". Thesis, University of Iowa, 2016. https://ir.uiowa.edu/etd/3144.

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Cervical vagal nerve stimulation (VNS) has been studied in the context of several conditions including epilepsy and depression. However, its effects on glucose metabolism, and its potentially beneficial effects in type II diabetes, have not yet been evaluated in humans. Efferent parasympathetic activation reduces hepatic glucose release and increases pancreatic insulin secretion, while afferent parasympathetic activation may increase hepatic glucose release and inhibit insulin secretion potentially through sympathetic activation. Thus, the effect of combined afferent and efferent cervical VNS is difficult to predict. We hypothesized that selective efferent VNS would decrease blood glucose concentration [Glu] and that selective afferent VNS would increase [Glu]. To investigate these potentially contrasting effects of efferent vs. afferent parasympathetic signaling, we recorded [Glu] and serum insulin and glucagon levels before and during 120 min of VNS in anesthetized rats. The nerve was left intact for combined afferent and efferent VNS (n=9) or sectioned proximal or distal from the stimulation electrode for selective efferent (n=8) of afferent (n=7) VNS, respectively. We found that afferent VNS caused a strong and sustained increase in [Glu] (+108.9±20.9% or +77.6±15.4% after 120 min of combined afferent and efferent VNS or selective afferent VNS) that was not accompanied by an increase in serum insulin concentration. Combined afferent and efferent VNS significantly increased serum glucagon concentration (57.6±23.4% at 120 min of VNS), while selective afferent VNS did not increase glucagon levels. Conversely, selective efferent VNS increased [Glu] only temporarily (+28.8±11.7% at 30 min of VNS). This response coincided with a transient increase in serum glucagon concentration at 30 min of VNS (31.6±8.3%) and a strong and sustained increase in serum insulin concentration (+71.2±27.0% after 120 min of VNS). These findings demonstrate that afferent VNS may increase [Glu] by suppressing pancreatic insulin release, while efferent VNS transiently increases [Glu] by stimulating glucagon secretion before reducing levels to or below baseline values by stimulating the release of insulin. Thus, selective efferent VNS may be potentially effective in the treatment of type II diabetes.

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29

Duteaux, Shelley Brown. "Trichloroethylene metabolizing enzymes in the male reproductive system : adducts and adverse effects in the epididymis and efferent ducts /". For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2003. http://uclibs.org/PID/11984.

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30

Boger, Adam Sprott. "Application of High Frequency Electrical Block on the Efferent Nerves to the Lower Urinary Tract for Bladder Voiding". Cleveland, Ohio : Case Western Reserve University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=case1238788042.

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31

Rosenfeld, Cheryl Susan. "Estrogen receptor-[alpha] and -[beta] regulation of the testes, ovaries, and male and female mesonephric-derived efferent ductules /". free to MU campus, to others for purchase, 2000. http://wwwlib.umi.com/cr/mo/fullcit?p9974680.

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32

Stanković, Konstantina Marka 1969. "Efferent effects on auditory-nerve responses to tones : substantial inhibition even at high sound levels and tail frequencies". Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/47442.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Whitaker College of Health Sciences and Technology, 1998.
Includes bibliographical references (leaves 134-140).
by Konstantina Marka Stanković.
Ph.D.

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33

CASTOR, XAVIER. "Influence de l'age sur les mecanismes actifs cochleaires et sur le systeme efferent olivo-cochleaire median chez l'humain". Besançon, 1993. http://www.theses.fr/1993BESA3075.

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34

Frappier, Brian Lee. "Localization of afferent and efferent innervation of the canine external anal sphincter muscle utilizing horseradish peroxidase neurohistochemical techniques /". The Ohio State University, 1988. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487592050227482.

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35

Taliaferro, Cheryl. "Ninth-grade Students’ Negotiation Of Aesthetic, Efferent, And Critical Stances In Response To A Novel Set In Afghanistan". Thesis, University of North Texas, 2011. https://digital.library.unt.edu/ark:/67531/metadc103398/.

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This qualitative, action research study was guided by two primary research questions. First, how do students negotiate aesthetic, efferent, and critical stances when reading a novel set in Afghanistan? Second, how do aesthetic and efferent stances contribute to or hinder the adoption of a critical stance? A large body of research exists that examines student responses to literature, and much of that research is based on the transactional theory of reading. However, it remains unclear how critical literacy fits into this theory. This study describes how one group of high school students’ aesthetic and efferent responses to a novel set in Afghanistan supported their development of critical stances. Six students enrolled in a ninth-grade English course participated in this study. Data were collected for 13 weeks. Data included two individual interviews with each student, student writing assignments in the form of 6 assigned journal entries and 7 assigned essays, transcriptions of 12 class discussions, field notes, lesson plans, a teacher researcher journal, and research memos. Data were analyzed using the constant comparative method. Three major findings emerged from this study. First, class discussions provided a context for students to adopt stances that were not evident in their individual written responses to the novel, which were completed prior to the discussions. Second, the discussions provided scaffolding that helped several of the students adopt world-efferent and critical stances. Third, both the aesthetic and the efferent stances contributed to students’ adoption of critical stances.

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36

Kazadi, Lubobo-Claude. "The effects of gastric and homeostatic autonomic afferent reflexes on cardiac autonomic efferent activity in healthy human volunteers". Thesis, University of Wolverhampton, 2015. http://hdl.handle.net/2436/600498.

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The effects of gastric autonomic afferent reflexes on cardiovascular autonomic efferent activity are regarded as a direct neural effect of the activation of gastric receptors which send afferent inputs to the central nervous system (CNS) to cause various cardiovascular changes (Van Orshoven et al., 2004; McHugh et al., 2010; Girona et al., 2014). However, the cardiovascular responses to liquid ingestion in humans may be related to gastric distension, volume loading effects, or to its osmotic proprieties. The purpose of this study was to investigate cross autonomic reflex function and to elucidate the effects of the resulting cardiac efferent autonomic activity in resting young healthy subjects. The ingestion of 300 mL of isothermic water increased both the cardiac vagal tone as indicated by increased RMSSD (mean 23.95 ± 20.50 msec increase, p<0.05) and sympathetic activity shown by increased QTc interval (mean 9.86 ± 8.59 msec increase, p< 0.05) during the first 40 minutes post-ingestion. These effects were absent with an identical volume of a physiological (0.9% w/v) saline solution which would increase plasma volume more, indicating that the cardiovascular responses to water drinking are influenced by its hypo-osmotic properties, rather than being related to the volume loading effects. Nevertheless, subjects responded to gastric distension with an ingestion of 300 mL of Fybogel solution with an increase in sympathetic activity during the first 20 minutes post-ingestion, but not in cardiac vagal tone. These results indicate that the mechanisms underlying the cardiovascular responses to water ingestion have additional components to the gastric stretch effect. Contrarily, the cold mediated sympathetic inhibition after drinking the same volume of either cold water or cold Fybogel solution probably happened in the NTS where the two branches of the ANS meet for the first time during their central pathway (Kubin et al., 2006; Thayer and Lane, 2009). In conclusion, the cardiovascular responses to water drinking are influenced by its hypo-osmolality properties and temperature, not by the volume loading effects.

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Sandberg, Cindy. "På en litterär resa : från planering till genomförande". Thesis, Högskolan Kristianstad, Sektionen för lärande och miljö, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:hkr:diva-9524.

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Genom närläsning av ämnesplanen i svenska samt semistrukturerade intervjuer med pedagoger är detta en undersökning som har fokuserat på varför och hur litteraturundervisning sker i klassrummet. Hur kan en pedagog tolka de nya styrdokumenten och därefter lägga upp undervisning i litteratur? Pedagogerna som intervjuades valde, ofta utan elevpåverkan, vilka skönlitterära texter som skulle belysas. Synen på hur litteraturhistorien skulle bearbetas skilde sig åt beroende på den gemensamma hållningen att låta elevernas intressen och erfarenheter stå i centrum. Under läsningen var den vanligaste inställningen att låta eleverna läsa enskilt hemma. Genom att besvara frågor, men även genom att ibland samtala bearbetades sedan läsningen. Såväl kunskapskraven i ämnesplanen som elevernas läslust satte upp ramarna för vilka didaktiska val som gjordes. Att använda multimediala texter var en av de främsta metoderna som nyttjades i syfte att skapa lust att lära om och av skönlitteratur.

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38

Mavoori, Jaideep. "Miniature animal computer interfaces : applied to studies of insect flight and primate motor pathways /". Thesis, Connect to this title online; UW restricted, 2006. http://hdl.handle.net/1773/5991.

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39

Andersson, Thomas, e Frida Johansson. "”Man lär sig fruktansvärt mycket om världen” : En studie kring hur en grupp svensklärare i grundskolans senare år arbetar med skönlitteratur". Thesis, Högskolan i Borås, Institutionen för Pedagogik, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-19531.

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BAKGRUND:Mycket av den forskning som finns kring skönlitteraturens roll i skolan utgår frånlitteraturvetaren Louise M. Rosenblatts teorier där ett värdegrundsarbete är det yttersta måletmed läsningen. Detta stämmer ganska väl överens med dagens kursplan i ämnet svenska. Vifrågar oss hur ett sådant arbete kan se ut i praktiken.SYFTE:Vårt syfte är att undersöka varför och hur en grupp svensklärare på en skola i grundskolanssenare del arbetar med skönlitteratur.METOD:Vi har genomfört en kvalitativ studie inriktad på hur några lärare ser på läsning avskönlitteratur, och har därför använt oss av den öppna ostrukturerade intervjun som redskap.RESULTAT:Vi har funnit att lärarna framhåller färdighetsträning i allmänhet och analytisk förmåga isynnerhet som det främsta syftet med skönlitteraturen. Det finns här en motsättning mellanlärarnas fokus och vad kursplanen i svenska ger för direktiv. Vi har sett tendenser till attläsning av ett efferent slag för träning av praktiska färdigheter dominerar över en estetiskläsning där upplevelsen av det lästa står i centrum. En förklaring till detta skulle kunna varakrav på måluppfyllelse, traditionella arbetssätt och rådande skolkultur – saker som kanskemånga gånger påverkar i större utsträckning är läroplaner och kursplaner.

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40

Maison, Stéphane. "Le faisceau olivocochléaire efférent médian chez l'humain : modalités d'activation centrale et périphérique : caractérisations fonctionnelles". Lyon 1, 1998. http://www.theses.fr/1998LYO1T244.

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41

Rabie, Salim Firas. "Högläsning som undervisningsmetod : En kvalitativ studie om gymnasielärares syn på högläsning i gymnasieskolan". Thesis, Mälardalens högskola, Akademin för utbildning, kultur och kommunikation, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-54822.

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Studiens syfte är att undersöka gymnasielärares arbete med och uppfattning om högläsning.Fyra lärare ingick i undersökningen där en kvalitativ ansats i form av semistruktureradeintervjuer användes. Resultatet visade att lärarna oftast använder högläsning i årskurs 1 pågymnasiet samt att högläsningen oftast kombineras med efterarbete. Lärarnas uppfattning omundervisningsmetoden är att högläsning kan ge elever ingång till litteratur men även att denkan hämma det självständiga läsandet. Slutsatsen av studien är att högläsning både harpositiva såväl som negativa effekter på elevers läsande och att metoden kan användas pågymnasiet för en varierad undervisning.

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42

Rosenthal, Allison Lianne. "Sulfated glycoprotein-1 (SGP-1) biosynthesis and its regulation within the nonciliated cells of rat efferent ducts : an in vivo study". Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=68250.

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The nonciliated epithelial cells of the efferent ducts are specialized in internalizing luminal fluid. They possess an extensive endocytic apparatus which provides an ideal system to study the kinetics of endocytosis. The nonciliated cells actively endocytose sulfated glycoprotein-1 (SGP-1, 70 kDa), a major secretory protein of Sertoli cells. A second form of SGP-1 (65 kDa) present in the secondary lysosomes of Sertoli and nonciliated cells of the efferent ducts is believed to be the equivalent of human prosaposin, the precursor of four small heat stable proteins (saposins A, B, C and D) required for the hydrolysis of sphingolipids by specific lysosomal hydrolases. This study was undertaken to investigate the contribution of Sertoli-derived SGP-1 as well as a putative endogenous SGP-1 within the secondary lysosomes of nonciliated cells. The hormonal control of endogenous lysosomal SGP-1, specifically the influence of testosterone withdrawal and its subsequent replacement was also examined. The results provide evidence that the nonciliated cells of the efferent ducts are involved in the clearance of testicular SGP-1 and reveal the presence of 15 kDa saposins and their 65 kDa precursor in secondary lysosomes of these cells. In addition, the production of an endogenous lysosomal SGP-1 targeted from the Golgi apparatus to the lysosomes after its glycosylation has also been demonstrated. The results further reveal that the endocytosis and lysosomal targeting of SGP-1 in nonciliated cells of the efferent ducts appear to be pituitary controlled.

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43

Berezina, Maria Andrey. "Medial olivocochlear efferent (MOC) effects on stimulus frequency otoacoustic emissions (SFOAEs) and auditory-nerve compound action potentials (CAP) in guinea pigs". Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/97822.

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Thesis: Ph. D., Harvard-MIT Program in Health Sciences and Technology, February 2015.
Cataloged from PDF version of thesis. "February 2015."
Includes bibliographical references.
In humans, SFOAEs can non-invasively assess MOC strength and, may predict the MOC reduction of damage from traumatic sounds. However, the functionally important MOC effect is inhibition of auditory-nerve (AN) responses. Understanding the relationship between MOC effects on SFOAEs and AN CAPs is important for understanding SFOAE generation and for development of clinical tools that use these measures. This thesis presents several novel data sets that address MOC effects on SFOAEs, CAPs and the relationship between them in guinea pigs. Classic theory indicates that SFOAEs come from cochlear irregularities that coherently reflect energy at the peak of the traveling wave (TW), and that reflected energy arrives in the ear canal as a single wave at certain delay. Contrary to theory, in humans and chinchillas there have been reports of SFOAEs having multiple components with different delays, and that lowfrequency SFOAE delays are too short. The first thesis aim used time-frequency analysis to show that guinea pigs have frequency regions over which SFOAEs appear to have multiple components. However, we argue that the multiple components can be a simple result of variations in the patters of irregularities near the TW peak and are not necessarily indicative of multiple SFAOE sources. From comparison of our SFOAE delays with previously reported neural delays, we hypothesize that short SFOAE delays at low frequencies arise from a cochlear motion with a group delay shorter than the TW group delay. Aim 2 investigated how SFOAEs are affected by brainstem electrical stimulation of MOC fibers and found that MOC activation sometimes inhibited and sometimes enhanced SFOAEs. MOC stimulation always decreased CAP sensitivity which rules out SFOAE enhancement from increased cochlear amplification. We propose that shock-evoked MOC activity increases cochlear irregularity which results in increased SFOAE amplitudes. Aim 3 investigated the relationship between MOC effects on SFOAEs and tone-pip-evoked AN CAPs at same frequency and sound level. The ratio of the MOC effect on the SFOAE to the MOC effect on the CAP showed a highly-significant decrease (p<0.001) as the strength of MOC stimulation was increased. Although this observation was unexpected, several hypothesis to explain it are presented.
by Maria Andrey Berezina.
Ph. D.

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44

Larsen, Erik Ph D. Massachusetts Institute of Technology. "Slow modulation of cochlear response by the olivocochlear efferent system elicited by sustained noise or threshold elevation in the contralateral ear". Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/45912.

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Thesis (Ph. D.)--Harvard-MIT Division of Health Sciences and Technology, 2008.
Includes bibliographical references (p. 95-101).
This thesis describes results from two projects related to the efferent innervation of the cochlea. First, we investigated peripheral olivocochlear effects of sustained contralateral broadband noise in anesthetized guinea pig. We found evidence of medial olivocochlear (MOC) effects on two timescales: the classic MOC 'fast effect', followed by a gradually increasing suppression, which we call the MOC 'delayed effect'. Delayed suppression typically takes 2-3 minutes to build up, occurs at all frequencies of guinea pig hearing, and suppresses distortion product otoacoustic emissions (DPOAEs), compound action potentials (CAPs), and round window noise. In contrast to the MOC slow effect, which has been reported for sustained shockevoked MOC activity, MOC delayed suppression does not build up in the outer hair cells but is due to a central modulation (enhancement) of MOC responsiveness and can thus be viewed as a gradual increase in the strength of the MOC fast effect. We found that, on average, the magnitude of the delayed suppression is comparable to that of the MOC fast effect, but that there is an overall negative correlation between fast and delayed effect magnitudes. Thus, it may have significant implications for the functional roles of the MOC system, such as protection against acoustic trauma, anti-masking, and dynamic range extension. Second, we investigated the LOC bilateral balancing model, which proposes that the LOC system acts to balance long-term average neural output from both cochleae, which would be important for binaural processing of sounds. For this, we tested various cohorts of mice by repeatedly measuring bilateral auditory brainstem responses (ABR) and "DPOAE growth functions across a wide range of frequencies and levels for periods of about 1-2 months. About halfway through the period, a unilateral reduction in neural output was created, either by acoustic overexposure or conductive impairment. Although the LOC balancing model predicts that the unilateral reduction in neural output should be matched contralaterally, we found no evidence for short-term or long-term efferent-induced contralateral response changes in any of the cohorts, either for DPOAE or ABR metrics.
(cont.) In view of these results, a revision of the LOC bilateral balancing model is called for.
by Erik Larson.
Ph.D.

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45

Röstlund, Linnéa. ""Man behöver inte älska att läsa men man ska ha läst böcker" : Efferent eller estetisk läsart i boksamtal inom högstadiets litteraturundervisning". Thesis, Stockholms universitet, Institutionen för kultur och estetik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-194868.

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Gelbke, Regine Maria [Verfasser]. "Effekt einer Botulinumtoxin-A-Injektion in den Detrusor auf efferent und afferent induzierte Blasenkontraktionen : Beobachtungen in einem chronischen Minipig-Modell / Regine Maria Gelbke". Kiel : Universitätsbibliothek Kiel, 2011. http://d-nb.info/1020245069/34.

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47

Larsson, Evelina. "Vad tycker elever är viktigast när de läser? : Vilken eller vilka läsarter tillämpas av en klass gymnasieelever i mötet med novellen Ett anspråkslöst förslag (Swift, 1729) i en skolkontext?" Thesis, Högskolan i Halmstad, Sektionen för lärarutbildning (LUT), 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-17228.

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This is a study of the reactions of high school students in Sweden when reading A Modest proposal (Swift, 1729). If they get the chance to write whatever they want about the text, what do they find important? This study emanates from Rosenblatts (2002) view of reading out of two different stances: the aesthetical and the efferent. The aesthetical mode is reading for pleasure and experiencing the text, whilst in efferent reading the reader is primarily focused on what he or she will carry away as information from the text (Rosenblatt). To be able to categorize the material from the students more properly, a different set of ideas about reading modes, obtained from Tengberg (2011), is also presented and used in this essay.

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48

Urnau, Daila. "CARACTERÍSTICAS AUDIOLÓGICAS DE INDIVÍDUOS NORMO-OUVINTES COM QUEIXAS DE ZUMBIDO E HIPERACUSIA". Universidade Federal de Santa Maria, 2011. http://repositorio.ufsm.br/handle/1/6505.

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OBJECTIVES: to verify the occurrence and the effect of transient otoacoustic emissions (TEOAE), existence of association between: tinnitus degrees and hyperacusis degrees, TEOAE suppressive effect and laterality, tinnitus and hyperacusis degrees, and verify the characteristics of normal hearing individuals with complaints of tinnitus and hyperacusis. MATERIALS AND METHODS: The study included 25 normal hearing subjects having complaints of tinnitus and hyperacusis, with 16 female and nine male. About tinnitus, the subjects were asked about the location and tinnitus type and they completed the Tinnitus Handicap Inventory (THI), used for the classification of tinnitus degrees. A developed hyperacusis questionnaire and the questionnaire on handedness The assessment and analysis of handedness: The Edinburgh Inventor were completed too. They were tested about the research of Loudness Discomfort Level (degrees of hyperacusis), Acuphenometry and the suppression effect of otoacoustic emissions (TEOAE) in the frequencies of 1, 1.5, 2, 3 and 4 KHz. We used descriptive and statistical analysis of the data (Fisher exact test, Kruskal Wallis and Mann Whitney U and Spearman correlation). RESULTS: The occurrence of TEOAE ranged from 33 to 88%. We observed the presence of TEOAE suppression effect on 63.7% in the right ear and 81.7% in the left ear. There was no association between tinnitus degrees and hyperacusis degrees, and between the TEOAE suppression effect and laterality, degrees of tinnitus and hyperacusis degrees. About tinnitus, the most subjects reported acute pitch, in anamnesis and in Acuphenometry, bilateral location and mild degree. Women had degree of tinnitus statistically superior than men. The sounds considered uncomfortable were the high intensity ones and the reaction to the sounds most often cited were irritation, anxiety and need to depart from the sound. The difficulty in speech understanding at noise was mentioned. CONCLUSION: We conclude that the occurrence of TEOAE in these subjects was lower than that found in normal hearing subjects. A higher percentage of presence of TEOAE suppression effect has been found in both ears. Degrees of tinnitus and hyperacusis degrees were not correlated in normal-hearing individuals with complaints of tinnitus and hyperacusis, and there was no association between the TEOAE suppression effect and laterality and degrees of tinnitus and hyperacusis. The sample presented acute pitch, bilateral location and mild bilateral tinnitus.High intensity sounds were reported as uncomfortable and irritation was the most cited reaction of the sound.
OBJETIVO: verificar a ocorrência e o efeito de supressão das emissões otoacústicas transientes (EOAT), a existência de associação entre: graus de zumbido e de hiperacusia, efeito supressor das EOAT e lateralidade, graus de zumbido e graus de hiperacusia, e analisar as características audiológicas de indivíduos normo-ouvintes com queixas de zumbido e hiperacusia. MATERIAIS E MÉTODOS: A amostra foi composta por 25 indivíduos normo-ouvintes, com queixas de zumbido e hiperacusia, sendo 16 do gênero feminino e nove do masculino. Em relação ao zumbido, os indivíduos foram questionados sobre o pitch e localização e preencheram o Tinnitus Handicap Inventory brasileiro (THI), utilizado para avaliar o grau de zumbido. O questionário de hiperacusia e o questionário sobre lateralidade manual The assessment and analysis of handedness: The Edinburgh Inventory também foram preenchidos. Os indivíduos foram submetidos a pesquisa do Loudness Discomfort Level (grau de hiperacusia), a acufenometria e a pesquisa e do efeito de supressão das emissões otoacústicas transientes (EOATs) nas frequências de 1, 1,5, 2, 3 e 4 KHz. Utilizou-se análise descritiva e estatística dos dados (testes exato de Fisher, Kruskal Wallis, U de Man Whitney e correlação de Spearman). RESULTADOS: A ocorrência das EOAT variou de 33 a 88%. Houve 63,7% de presença de efeito de supressão na orelha direita e 81,7% na orelha esquerda. Não ocorreu associação significativa entre os graus de zumbido e os graus de hiperacusia, e entre o efeito supressor das EOAT e lateralidade, graus de zumbido e graus de hiperacusia. Em relação ao zumbido, a maioria dos indivíduos apresentou pitch agudo, tanto na anamnese quanto na acufenometria, localização bilateral e grau leve no THI. As mulheres apresentaram grau de zumbido estatisticamente superior ao dos homens. Os sons considerados desconfortáveis foram os de alta intensidade e as reações aos sons mais citadas foram a irritação, ansiedade e necessidade de afastar-se do som. A dificuldade de compreensão de fala na presença de ruído foi referida pela maioria dos indivíduos.CONCLUSÃO: Conclui-se que a ocorrência de EOAT foi inferior a encontrada em sujeitos normo-ouvintes sem esses sintomas. Obteve-se maior percentual de presença do efeito de supressão das EOATs em ambas as orelhas analisadas. Os graus de zumbido e os graus de hiperacusia não apresentaram correlação em indivíduos normo-ouvintes com queixas de zumbido e hiperacusia, bem como não ocorreu associação entre o efeito de supressão das EOAT e lateralidade, graus de zumbido e de hiperacusia. A amostra estudada apresentou predomínio de zumbido de pitch agudo, localização bilateral e grau leve. Os sons considerados desconfortáveis foram os de alta intensidade e a reação de irritação aos sons foi a mais citada.

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49

Broman, Sofia, e Josefine Karlqvist. "Vad motiverar elever att läsa? En fallstudie av vilka faktorer elever på högstadiet anser ökar deras motivation att läsa skönlitteratur". Thesis, Malmö högskola, Fakulteten för lärande och samhälle (LS), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-30582.

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Med bakgrund i elevers minskade läsförståelse och svenskämnets uppdrag har vi idetta arbete undersökt vilka faktorer som motiverar elever på högstadiet att läsaskönlitteratur. Utifrån det insamlade materialet har vi även gjort en analys av vilkaskillnader det finns mellan flickors och pojkars syn på vad som motiverar dem att läsaskönlitteratur. Materialet har samlats in genom fyra fokusgruppsintervjuer, två medflickor och två med pojkar. Resultatet visar att både flickorna och pojkarna uppleveratt de faktorer som kan öka motivationen att läsa är igenkänning i texten, lagomsvårighetsgrad i uttrycksform och innehåll och tid för läsning. Pojkarna görjämförelser med datorspel och menar att datorspelens uppbyggnad bör appliceras påskönlitteraturen för att öka motivationen att läsa. Motviljan mot läsning som framkomi fokusgrupperna tolkar vi som en bristande förmåga att orientera sig igenomskönlitteratur-literacien snarare än en bristande motivation. Vår slutsats är att läraren isin undervisning bör eftersträva en matchning mellan eleven och texten. En estetiskläsning av texter bör ske i alla skolämnen för att höja läsningens status och läraren böräven ge tid för läsning under skoltid

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50

Vujovic, Nina. "Functional organization of the circadian timing system". Thesis, Harvard University, 2013. http://dissertations.umi.com/gsas.harvard:11271.

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The circadian timing system establishes daily rhythms in behavior and physiology throughout the body, ensuring that functions like activity, sleep and hormone release are appropriately timed. Research suggests that his temporal synchrony within the body is quite important for health and survival. In mammals, the central circadian pacemaker in the suprachiasmatic nucleus (SCN) drives rhythms in behavior and physiology in large part by stimulating or inhibiting other brain regions responsible for these functions at the appropriate times of day. This timed signal is often indirect, i.e. relayed or possibly processed through a series of neurons in different brain regions before reaching the effector site. The subparaventricular zone (SPZ), a region adjacent to the SCN which is the main recipient of direct neuronal inputs from the SCN, is thought to be a critical relay for SCN signals, since loss of the SPZ results in loss of circadian rhythms in body temperature, activity and sleep/wakefulness. Another important relay site, the dorsomedial hypothalamic nucleus (DMH) gets direct input from both the SCN and SPZ and is critical for normal expression of various circadian rhythms.

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