• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 9
  • 5
  • 2
  • 1
  • 1
  • 1
  • Tagged with
  • 24
  • 6
  • 5
  • 4
  • 4
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 2
  • 2
  • 2
  • 2
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Travel bound and the need for vacation a phenomenological study to understand the tourism experiences of at risk youth

Richards, Alix S. 12 September 2016 (has links)
This study offers a better understanding of the tourism experiences of at risk youth. A Husserlian phenomenology consisting of semi-structured interviews with a group of at risk youth residing in a treatment centre reveals a broader understanding of the tourism phenomenon as well as the essence of these experiences. Findings revealed that at risk youth value tourism and the opportunities that these experiences provide. The importance of support during this multi-phasic experience contributed to outcomes including increased learning opportunities, liberty to exercise free-choice and independence, skill acquisition, gains in social capital, improved self-perception and ultimately, increased resilience. / October 2016
2

Differential regulation of MLC20 phosphorylation in tonic and phasic smooth muscles of the stomach

Al-Shboul, Othman 05 April 2011 (has links)
Gastrointestinal (GI) smooth muscle possesses distinct regional and functional properties that distinguish it from other types of visceral and vascular smooth muscle. On the basis of electrical properties and contractile phenotype, GI smooth muscles have been classified into phasic (non-sphinteric) and tonic (sphinteric) smooth muscles. The biochemical basis of phasic and tonic phenotypes of smooth muscle is not clear and is the major question of inquiry of the present study. Phosphorylation of Ser19 on the 20 kDa myosin light chain (MLC) is essential for acto-myosin interaction and contraction in both phasic and tonic muscles. The levels of MLC20 phosphorylation are regulated by Ca2+/calmodulin-dependent MLC kinase (MLCK) and MLC phosphatase (MLCP), and the activity of these enzymes are in turn regulated by various signaling molecules whose expression and activity are important in determining the strength and duration of their activity. The signaling proteins are AMP kinase (MLCK activity), Rho kinase, zipper-interacting protein kinase (ZIPK), CPI-17 and telokin (MLCP activity), phosphodiesterase 5 (PDE5) and multi-drug resistance protein 5 (MRP5). The overarching goal of the dissertation is to identify the differences in the signaling pathways that regulate MLCK and MLCP activities, and thus MLC20 phosphorylation and muscle function. Using biochemical, molecular and functional approaches, and antrum (distal stomach) and fundus (proximal stomach) of rabbit stomach as models of phasic and tonic smooth muscles, respectively, the present study characterized important differences in the signaling pathways that highly correlate with the contractile phenotype. These include: 1) tissue-specific expression of contractile proteins such as myosin heavy chain isoforms, actin, caldesmon, calponin, - and β-tropomyosin, smoothelin-A and -B; 2) higher expression of AMPK, selective feedback inhibition of MLCK activity via AMPK-mediated phosphorylation, and higher expression of telokin and activation of MLCP correlate with the rapid cyclical contractile function in phasic muscle; 3) higher expression and activation of Rho kinase/ZIPK/MYPT1 and PKC/CPI-17 pathways, preferential inhibition of MLCP activity, and sustained phosphorylation of MLC20 correlate with the sustained contraction in tonic muscle; and 4) rapid termination of cGMP signal and muscle relaxation by preferential degradation and efflux of cGMP via higher expression of PDE5 and MRP5, respectively, correlate with the brief relaxation and rapid restoration of contraction in tonic muscle. It is anticipated that these findings could be important in providing the underlying mechanisms involved in the pathophysiology of smooth muscle function and new insights for the development of therapeutic agents that should act on smooth muscle in the gut to treat motility disorders as well as in other regions such as airways and vascular smooth muscle where similar intracellular mechanisms may prevail.
3

Möjligheternas städer? : En kohortstudie av social mobilitet under urbaniseringen i Sverige 1890-1940 / Cities of possibility? : A cohort study of social mobility during the urbanization of Sweden 1890-1940.

Berggren, Evelina January 2024 (has links)
Cities of possibility? – A cohort study of social mobility during the urbanization of Sweden 1890-1940  This cohort study examines the social mobility of countryside migrants to Swedish cities in the period of 1890-1940. The purpose is to determine whether the claim that cities had enhanced possibilities for the individual and therefore offered a chance for social advancement. The question in operation is whether migration to a city meant an improved social advancement. To aid the analysis classic urbanization theory and multi-phasic demographic response were added. To observe the social mobility in cities a cohort of 315 people born in the southeast of Kalmar län in the year 1890 were observed on indicators of geographical and social mobility as well as family life. This group was then divided into one cohort that moved to the cities and one that stayed in the countryside. The study found, in agreement with previous research on the area, that most of the individuals moving to the cities were from a blue-collar [obesutten] background and that this group had a small majority of women. The individuals from a white-collar [besutten] background mostly skirted the cities, preferring to stay in the countryside or to emigrate. However, Swedish urbanization studies of this period have not agreed on whether cities had a positive, neutral, or negative impact on the social mobility of those who migrated there. This study found a complicated pattern where blue-collar women had an improved social advancement in the cities. Meanwhile, white-collar women had a larger risk of degrading socially and blue-collar men in the cities had the least mobility of all groups involved. To summarize, migration to the cities were mostly a choice by those with blue-collar background and while the women did enhance their social advancement as a group the rest of those who urbanized were negatively impacted. This, on top of only a few white-collar women and only two white-collar men choosing to move to a city indicates, with aid of the theory of multi-phasic demographic response, that cities mostly did not offer an opportunity better than the countryside or a life overseas could. Hence, it was found that cities did not improve social advancement.
4

Maturação nuclear e citoplasmática de oócitos de cadelas colhidos em diferentes fases do ciclo estral e cultivados in vitro em meios sequenciais com hormônios e espermatozóides /

Apparício-Ferreira, Maricy. January 2010 (has links)
Orientador: Wilter Ricardo Russiano Vicente / Banca: Camila Infantosi Vannucchi / Banca: Lúcia Daniel Machado da Silva / Banca: Maria Denise Lopes / Banca: Marion Burkhardt Koivisto / Resumo: Este estudo foi realizado com o intuito de avaliar comparativamente os efeitos do emprego de meios seqüenciais com hormônios no desenvolvimento meiótico e citoplasmático de oócitos caninos durante o período de cultivo de 72 horas. Os oócitos foram coletados de 49 cadelas hígidas submetidas à ovariosalpingo-histerectomia ou ovariectomia, divididas em três grupos de acordo com seu status reprodutivo (fase folicular, lútea e anestro). Os óocitos foram aleatoriamente distribuídos em quatro sistemas de cultivo diferentes sendo o meio básico (MB) o TCM 199 suplementado. Os demais consistiam: no sistema A (controle) os oócitos foram maturados por 72 horas no (MB) com 10 UI/mL de hCG, 1 mg/mL de progesterona (P4) e 1 mg/mL de estradiol (E2), ou seja, expostos de forma contínua à estes hormônios; no sistema seqüenciado B os oócitos foram maturados no meio base com hCG por 48 horas e nas 24 horas adicionais no MB com P4; no sistema seqüenciado C os oócitos foram maturados no MB com hCG, P4 e E2 por 48 horas e nas 24 horas adicionais no MB com P4; no sistema D (controle) os oócitos foram maturados no MB, sem hormônios. Nos meios B e C, os hormônios foram suplementados nas mesmas concentrações empregadas no sistema A. Os resultados evidenciaram efeito positivo dos meios seqüenciais na progressão da meiose e na maturação citoplasmática (P<0,05). Não houve influência da condição reprodutiva das fêmeas doadoras nas taxas de maturação oocitária (P>0,05). A presença de espermatozóides nos meios de cultivo não teve efeito benéfico sobre as taxas de MII; em contrapartida, a porcentagem de oócitos degenerados aumentou consideravelmente (P>0,05). / Abstract: The aim of this work was to study the influence of different bi-phasic systems with gonadotrophins and steroids on meiotic and cytoplasmic development of canine oocytes cultured for 72 hours. Oocytes were collected after ovariohysterectomy or ovariectomy from 49 healthy bitches, divided into 3 groups according to their reproductive status (follicular, luteal and anestrous stages). Oocytes were randomly allocated in four different culture systems with the base medium (BM) consisting of TCM-199. The systems were as follows: in system A oocytes were matured for 72 h in BM with 10 UI/mL hCG, 1 mg/mL progesterone (P4), 1 mg/mL estradiol (E2); in bi-phasic system B oocytes were matured for 48 h in BM with hCG and for 24 h in BM with P4; in bi-phasic system C oocytes were matured for 48 h in BM with hCG, P4 and E2, and for 24 h in BM with P4. In system D (control), oocytes were cultured in BM without hormones. In sytems B and C hormones were supplemented at the same doses as in system A. The results suggest that the use of bi-phasic systems was beneficial for oocyte meiosis and cytoplasmic maturation (P<0,05). No difference was noticed with regards to the influence of reproductive status on maturation rates (P>0,05). The addition of spermatozoa to the medium had no benefit on MII stage rates (P>0,05); however, the percentage of degenerated oocytes has significantly increased. / Doutor
5

PMS: Bi-Phasic Differences in Personality and Marital Relations Among a Clinical Sample

Rogers, Donna R. 01 May 1987 (has links)
Premenstrual Syndrome (PMS) is a controversial and widely misunderstood syndrome which encompasses mood, behavior, and physical symptoms that occur cyclically and are associated with the menstrual cycle. Many women report suffering from recurring PMS symptoms severe enough to create a temporary physical or mental incapacitation which may affect the marital relationship. A study was initiated to document bi-phasic personality and marital changes related to PMS. This sample consisted of 119 adult females and their husbands, ranging in age between 18 and 60, who sought diagnosis and treatment at the Utah PMS Center in Salt Lake City, Utah. Within this clinical sample, comparisons were made between those who appeared to have the most positive indicators of PMS, as identified by the Dalton Diagnostic Pointer, the monthly symptom calendar, and the dOCtor's diagnostic impression, and those who did not, according to the same criteria. The marital relationship was assessed by both husband and wife during the follicular (approximately day 6 to day 14) and luteal (approximately day 14 to first day of menses) phases of the menstrual cycle using the Locke-Wallace Marital Adjustment Scale. Personality changes were measured by the Minnesota Multiphasic Personality Inventory (MMPO, which was administered to the wife only during both phases. Repeated measures analysis of variance was used to determine if I) for the entire sample, there are differences in women's mental health, and marital adjustment (as reported by both husband and wife) between the two cyclic phases, and 2) whether or not mental health and marital adjustment changes are similar between those women with positive indicators of PMS, versus those without. Final results of this study show that, overall, the entire sample is reporting significantly less healthy personality adjustment for the wife, as well as lower marital adjustment for both husband and wife during the symptomatic phase. There are some indications that, although these changes are present in both groups (those with PMS and those without), the changes are less dramatic for those women and couples with less likelihood of PMS. These findings have important implications for counselors and marriage therapists in that PMS has been shown to be related to psychological dysfunction and marital stress. Diagnosticians who test women during the symptomatic phase and obtain test results which are not representative of the client"s overall health and well-being would also benefit from the results of this study. These findings have important implications for counselors and marriage therapists in that PMS has been shown to be related to psychological dysfunction and marital stress. Diagnosticians who test women during the symptomatic phase and obtain test results which are not representative of the client"s overall health and well-being would also benefit from the results of this study.
6

SPECIFIC OR NONSPECIFIC: INVESTIGATING THE EFFECT OF EVENT-BASED SEQUENTIAL MODULATION ON TEMPORAL PREPARATION

Tianfang Han (9739232) 25 April 2023 (has links)
<p>Anticipating the occurrence of a future event is an ability that helps people prepare for various daily activities. This preparation is regarded as a non-specific process because it is initiated by a warning signal that does not contain specific information about the critical event. Previous research reported that the intertrial repetition of a stimulus-response event in a choice-reaction task shortened the reaction time more at the short foreperiod (interval between the end of the warning signal and onset of the target stimulus). I conducted four experiments to investigate whether the interaction was due to the event sequence effect being overridden by preparation processes (“overriding” hypothesis) or the quick-decaying characteristic of the event sequence effect itself (“quick-decay” hypothesis). Experiments 1 and 2 manipulated the relative magnitudes of the preparation effect by changing how foreperiods were distributed within a trial block. The results showed similar asymmetric event sequence effects, which indicated that whether preparation was better at the short or long foreperiod did not affect the event-based modulation. Experiment 3 manipulated the temporal distance between two consecutive stimulus-response events across trial blocks and found that the asymmetric event-based modulation on preparation was diminished by a long enough inter-trial interval. The final experiment compared alerting trials with no-alerting trials and found an asymmetric event-based modulation caused by the absence of repetition benefit in a certain context (an alerting trial preceded by a no-alerting trial). Therefore, the event sequence effect is not directly related to “nonspecific preparation”, but this event-specific component could be embedded in the measurement of preparation in some scenarios, which could lead to misinterpretation of the preparation effect itself. This finding clarifies the mechanism underlying the interaction between preparation and event sequence. The conclusion also questions the validity of the current measures of nonspecific preparation, including temporal preparation and phasic alertness.</p>
7

MECHANISMS OF NEURODEGENERATION IN A MOUSE MODEL OF SANDHOFF DISEASE: ROLES OF INFLAMMATION, EXCITOTOXICITY, AND APOPTOSIS / MECHANISMS OF NEURODEGENERATION IN A MOUSE MODEL OF SANDHOFF DISEASE

Hooper, Alexander William Maurice January 2016 (has links)
Lysosomal storage disorders are a group of rare neurodegenerative diseases that are collectively common, sharing many aspects with other neurodegenerative disorders, including substrate build-up and neuroinflammation. The GM2 Gangliosidoses, Tay-Sachs disease and Sandhoff disease, are pathologically overlapping lysosomal storage disorders, with high prevalence within specific ethnicities. Their effects are neurologically devastating and often fatal at young ages. Current treatments only slow or stall an inevitable decline in health. Novel treatment targets are needed for these disorders, and others with similar pathologies. In these works we demonstrate the negative effect the inflammatory cytokine tumour necrosis factor-alpha has on survival of a model of Sandhoff disease. We demonstrate its role in the upregulation of astrogliosis, and apoptosis, and we present evidence that this effect on astrogliosis occurs through an upregulation of the JAK-2/STAT3 pathway. Though fruitful, a singular focus on inflammation/gliosis in these diseases has left a vacuum in the research into neuron specific molecular processes. We observe the development of inflammation, astrogliosis and neuronal processes in our model, and demonstrate a bi-phasic disease progression, in which early onset microgliosis precedes terminal astrogliosis, apoptosis, and a decline in excitatory glutamate receptors, suggesting neuron-specific malfunction. Furthermore, we show that knockout of the synaptic protein neuronal pentraxin 1 retards neurodegeneration and extends the lifespan of Sandhoff disease mice, independent of inflammation or astrogliosis. Through electrophysiology, we provide evidence of dysregulation of glutamate receptors in Sandhoff disease, and show that knockout of neuronal pentraxin 1 provides rescue from this dysregulation. This work expands on research into gliosis in GM2 gangliosidoses, presents the finding of a novel protein isoform, and presents a new focus on non-glial disease mechanisms and treatments for these and other neurodegenerative disorders. / Thesis / Doctor of Philosophy (PhD) / Lysosomal storage disorders are a group of neurological diseases that are debilitating, and often fatal at a young age. Two diseases of this group- Tay-Sachs disease and Sandhoff disease – are similar in their causes and symptoms. Current treatments for these diseases only slow or stall an inevitable decline in health. New targets for treatment are required, and we provide data suggesting several proteins that may fit this criterion. We also provide evidence of the discovery of a new form of one of these proteins, which is found in high levels in the disease, indicating it may be important in these and other neurodegenerative diseases. Finally, we provide findings indicating that a certain cell type, which is largely ignored in current research for these diseases, may be important in the disease progress. These findings increase our knowledge of Tay-Sachs disease and Sandhoff disease, and open new avenues for medicinal intervention.
8

The effect of musical tempo on subjective and physiological indices of affective response

Ellis, Robert J. 28 September 2009 (has links)
No description available.
9

Alavo fosfido fotoelektroninis spektras / Photo electronis spectra of tin fosfydium

Eidrigevičius, Saulius 30 June 2009 (has links)
Šiame baigiamajame magistro darbe nagrinėjamas alavo fosfido fotoelektroninis spektras. Tyrimo objektu pasirinktas Sn2P2S6 kristalas. Jis pasižymi pirmos rūšies faziniu virsmu. Kambario temperatūroje yra feroelektrikas, 360 K temperatūroje paraelektrikas. Darbe nagrinėjami kristalo fotoelektroninio spektro atlikto XPS metodu skitrumai po fazinio virsmo, bei atliktas lyginimas su teoriniu kristalo modeliu. Teorinis modelis remiasi Hartre-Foko-Rutano metodu. / In this graduating master`s work is researched photo electronis spectra of tin fosfydium crystal (Sn2P2S6). It is unique by ability to be feroelectric in ferophase (room temperature) and papaelectric in paraphase (360 K). In this work we are researching XPS differences of given crystal after the phasic transformation. Also we are comparing experimental XPS to theoretical crystal model, made by Hartree-Fock-Rutan method.
10

Maturação nuclear e citoplasmática de oócitos de cadelas colhidos em diferentes fases do ciclo estral e cultivados in vitro em meios sequenciais com hormônios e espermatozóides

Apparício-Ferreira, Maricy [UNESP] 26 February 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-02-26Bitstream added on 2014-06-13T18:46:21Z : No. of bitstreams: 1 apparicioferreira_m_dr_jabo.pdf: 8938205 bytes, checksum: 540b8a495ebda2425790114eece3d47a (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Este estudo foi realizado com o intuito de avaliar comparativamente os efeitos do emprego de meios seqüenciais com hormônios no desenvolvimento meiótico e citoplasmático de oócitos caninos durante o período de cultivo de 72 horas. Os oócitos foram coletados de 49 cadelas hígidas submetidas à ovariosalpingo-histerectomia ou ovariectomia, divididas em três grupos de acordo com seu status reprodutivo (fase folicular, lútea e anestro). Os óocitos foram aleatoriamente distribuídos em quatro sistemas de cultivo diferentes sendo o meio básico (MB) o TCM 199 suplementado. Os demais consistiam: no sistema A (controle) os oócitos foram maturados por 72 horas no (MB) com 10 UI/mL de hCG, 1 mg/mL de progesterona (P4) e 1 mg/mL de estradiol (E2), ou seja, expostos de forma contínua à estes hormônios; no sistema seqüenciado B os oócitos foram maturados no meio base com hCG por 48 horas e nas 24 horas adicionais no MB com P4; no sistema seqüenciado C os oócitos foram maturados no MB com hCG, P4 e E2 por 48 horas e nas 24 horas adicionais no MB com P4; no sistema D (controle) os oócitos foram maturados no MB, sem hormônios. Nos meios B e C, os hormônios foram suplementados nas mesmas concentrações empregadas no sistema A. Os resultados evidenciaram efeito positivo dos meios seqüenciais na progressão da meiose e na maturação citoplasmática (P<0,05). Não houve influência da condição reprodutiva das fêmeas doadoras nas taxas de maturação oocitária (P>0,05). A presença de espermatozóides nos meios de cultivo não teve efeito benéfico sobre as taxas de MII; em contrapartida, a porcentagem de oócitos degenerados aumentou consideravelmente (P>0,05). / The aim of this work was to study the influence of different bi-phasic systems with gonadotrophins and steroids on meiotic and cytoplasmic development of canine oocytes cultured for 72 hours. Oocytes were collected after ovariohysterectomy or ovariectomy from 49 healthy bitches, divided into 3 groups according to their reproductive status (follicular, luteal and anestrous stages). Oocytes were randomly allocated in four different culture systems with the base medium (BM) consisting of TCM-199. The systems were as follows: in system A oocytes were matured for 72 h in BM with 10 UI/mL hCG, 1 mg/mL progesterone (P4), 1 mg/mL estradiol (E2); in bi-phasic system B oocytes were matured for 48 h in BM with hCG and for 24 h in BM with P4; in bi-phasic system C oocytes were matured for 48 h in BM with hCG, P4 and E2, and for 24 h in BM with P4. In system D (control), oocytes were cultured in BM without hormones. In sytems B and C hormones were supplemented at the same doses as in system A. The results suggest that the use of bi-phasic systems was beneficial for oocyte meiosis and cytoplasmic maturation (P<0,05). No difference was noticed with regards to the influence of reproductive status on maturation rates (P>0,05). The addition of spermatozoa to the medium had no benefit on MII stage rates (P>0,05); however, the percentage of degenerated oocytes has significantly increased.

Page generated in 0.0484 seconds