This thesis reports on a case study which explores the nature and processes of entrepreneurship learning, teaching and assessment centred on the experiences of a group of students enrolled on an ...undergraduate entrepreneurship degree programme in the UK. It contributes towards an understanding of entrepreneurship education by exploring how students learn and construct knowledge within a curriculum that has an emphasis on experiential and action-based form of learning located in the university settings and through work-integrated learning. This study utilised a mixed methods approach whereby a combination of literature reviews and in-depth interviews have been utilised to generate data to explore the research questions. Presented in a journal format, I report and theorise on my research findings in four outputs in the form of journal articles. The first output, How do we teach entrepreneurship in university? A conceptual review of the literature, presents a conceptual review of the published literature in the teaching practices of entrepreneurship in higher education and synthesise the conceptual developments and diverse empirical findings towards a more integrated understanding of how to teach entrepreneurship in university. The second output, Assessment practices in entrepreneurship education in higher education: A scoping review of the literature, presents a scoping review of the published literature in the assessment practices of entrepreneurship education within which I discuss and develop a conceptual synthesis of the key concepts in the field. The third and fourth outputs report on the empirical findings of the in-depth interviews. The third output, Towards an understanding of how university students learn within an entrepreneurship education programme, explores how students learn entrepreneurship and construct knowledge through a range of learning activities within the curriculum as well as social interactions with tutors and peers inside and outside the classroom. The fourth output, Work-integrated learning in entrepreneurship education: A case study of the experiences of university students within an undergraduate entrepreneurship programme, explores the work-integrated learning experiences of entrepreneurship students during work placements and how they translate entrepreneurship learning into practice at the workplace. I conclude with a critical synthesis of the findings of the four outputs against my research questions, a summary of the contributions to knowledge and implications for academic practice, and recommendations for further research. Taken as a whole, this study makes original contributions to knowledge in its claim that entrepreneurship learning can be perceived and understood as a process of construction in which students construct what they know on the basis of their experience. Learning and development are not solely the outcomes of engagement with activities within an education curriculum and that such activities need to be understood as part of a fuller engagement between teachers, students and the various environments in which they evolve within their lifeworlds.
Most but not all of the established insulin-like growth factor-binding proteins (IGFBPs) are expressed in the rat ovary. To continue the process of characterizing these ovarian IGFBPs, a solution ...hybridization/RNase protection assay was used to study IGFBP-6 gene expression, cellular localization, and hormonal regulation in the immature rat ovary. Total RNA was hybridized with a 458-base long 32P-labeled rat IGFBP-6 cRNA. A single protected fragment (380 bases long) corresponding to IGFBP-6 transcripts was identified in RNA from ovary and lung, but not kidney or liver. The amount of IGFBP-6 transcripts was higher in ovaries from immature rats (25-28 days old) than in ovaries from adult rats and was higher in theca-interstitial than in granulosa cell preparations. Hypophysectomy resulted in a significant (P < 0.05) 2.3 +/- 0.7-fold (mean +/- SD) increase in whole ovarian IGFBP-6 transcripts. This suggests that ovarian IGFBP-6 gene expression is subject to inhibition by one or more pituitary hormones. Therefore, the effect of replacement of FSH, GH, diethylstilbestrol (DES), or combinations thereof was evaluated. Treatment with FSH resulted in a 2.4-fold decrease (P < 0.05) in the abundance of ovarian IGFBP-6 transcripts relative to that in hypophysectomized controls. Provision of DES yielded comparable results. Moreover, the combined provision of FSH and DES resulted in a synergistic decrease (6.0-fold) in ovarian IGFBP-6 transcripts. In contrast, treatment of hypophysectomized rats with GH proved without effect. However, treatment with FSH or DES in addition to GH resulted in a decrease in ovarian IGFBP-6 transcripts (3.9- and 2.7-fold, respectively). To assess the role of ovarian IGFBP-6, its influence on gonadotropin action in primary cultures of rat granulosa cells was also studied. Increasing concentrations (0.01-1 micrograms/ml) of recombinantly expressed human IGFBP-6 did not inhibit the FSH-supported accumulation of either progesterone or estradiol. These findings 1) establish the theca-interstitial compartment of the immature rat ovary as a prominent site of IGFBP-6 gene expression, 2) implicate FSH and DES as inhibitors of IGFBP-6 transcript levels in the whole ovary, 3) and disclose the limited antigonadotropic action of IGBP-6F on the rat granulosa cell.
Transcatheter aortic valve replacement (TAVR) has become the standard of care in the majority of patients with symptomatic severe aortic stenosis. Data on long-term mortality and durability of ...transcatheter heart valves (THVs) beyond 5 years are limited. Our study aimed to assess elderly and high-risk patients’ long-term outcomes treated with TAVR in a prospective single-centre registry focusing on the durability of THVs.
We included 795 patients with severe calcific aortic stenosis treated by transfemoral TAVR between 2006 and 2011. Echocardiography was performed at baseline; discharge; 1 year; and afterward, annually, until the longest available follow-up. Mortality rates were estimated for 1, 5, 6, 7, and 8 years. The rates of structural valve deterioration (SVD) and bioprosthetic valve failure (BVF) were assessed in accordance with consensus definitions. Outcome measures were adjudicated according to Valve Academic Research Consortium-2 (VARC-2).
Median (interquartile range) follow-up time was 1345 (316; 2015) days. One-year, 5-year, 6-year, 7-year, and 8-year overall mortality was 25.4%, 59.0%, 64.6%, 67.9%, and 69.2%, respectively. At 8 years, no significant differences in mortality were found comparing self-expanding vs balloon-expandable valves (69.5% vs 68.0%, P = 0.709) and postdilatation (PD) vs no-PD (69.4% vs 69.2%, P = 0.363). SVD was detected in 26 patients (3.3%), and 19 (2.4%) of the 795 patients had evidence of BVF during follow-up.
Our study demonstrates good long-term results for high-risk patients who were alive up to 8 years after TAVR.
Le remplacement valvulaire aortique par cathéter (RVAC) est maintenant la norme de soins dans la majorité des cas de sténose de l’aorte grave symptomatique. On dispose de peu de données sur la mortalité à long terme et sur la durabilité des valves cardiaques transcathéter (VCT) au-delà de 5 ans. Nous avons donc évalué les résultats à long terme, notamment la durabilité des VCT, chez les patients âgés et les patients exposés à un risque élevé traités par RVAC figurant dans un registre prospectif unicentrique.
Notre étude comprenait 795 patients présentant une sténose calcifiée de l’aorte grave traitée par RVAC transfémoral entre 2006 et 2011. Une échocardiographie a été réalisée au départ, à la sortie de l’hôpital, 1 an plus tard et tous les ans par la suite, jusqu’au suivi le plus long disponible. Les taux de mortalité à 1, 5, 6, 7 et 8 ans ont été estimés. Les taux de détérioration structurelle des valves (DSV) et de défaillance de la bioprothèse valvulaire (DBV) ont été évalués selon des définitions établies par consensus. Les mesures des résultats ont été confirmées selon les critères du VARC-2 (Valve Academic Research Consortium-2).
La durée médiane (intervalle interquartile) du suivi était de 1 345 (316 à 2 015) jours. Les taux de mortalité globaux s’établissaient comme suit : taux à 1 an : 25,4 %; à 5 ans : 59,0 %; à 6 ans : 64,6 %; à 7 ans : 67,9 % et à 8 ans : 69,2 %. À 8 ans, on n’a noté aucune différence significative en ce qui concerne la mortalité chez les patients ayant reçu une valve auto-expansible comparativement à ceux ayant reçu une valve expansible par ballonnet (69,5 % vs 68,0 %; p = 0,709) et chez ceux ayant subi une post-dilatation ou non (69,4 % vs 69,2 %; p = 0,363). Une DSV a été détectée chez 26 patients (3,3 %), et 19 (2,4 %) des 795 patients ont présenté des signes de DBV pendant la période de suivi.
Notre étude a révélé de bons résultats à long terme chez les patients présentant un risque élevé qui étaient toujours en vie 8 ans après le RVAC.
The Bcl-2 homologue, Bak, is a potent inducer of apoptosis. FISH data presented here located the gene to 6p21.3. Mapping was consistent with its location centromeric of the
HSET locus and ...approximately 400
kb from the MHC. The construction of a contig of genomic clones across the locus facilitated the sequencing of a PAC containing the gene. Comparison of the gene structure to functional and physical domains revealed a good agreement between the physical structure and the intron–exon organisation. The position of a single intron was conserved in comparison to other members of the Bcl-2 family, namely
Bax,
CED-9,
Bcl-X and
Bcl-2, but all other introns were displaced, consistent with a divergent phylogeny.
The retrieval of NO and Tk from MIPAS upper atmospheric observation is described NO and Tk climatology is compared to models Diurnal variations of thermospheric NO are analyzed We present vertically ...resolved thermospheric temperatures and NO abundances in terms of volume mixing ratio retrieved simultaneously from spectrally resolved 5.3 m emissions recorded by the Michelson Interferometer for Passive Atmospheric Spectroscopy (MIPAS) in its upper atmospheric observation mode during 20052009. These measurements are unique since they represent the first global observations of temperature and NO for both day and night conditions taken from space. A retrieval scheme has been developed which accounts for vibrational, rotational and spin-orbit non-LTE distributions of NO. Retrieved polar temperature and NO profiles have a vertical resolution of 510 km for high Ap values, and degrade to 1020 km for low Ap conditions. Though retrieved NO abundances depend strongly on the atomic oxygen profile used in the non-LTE modeling, observations can be compared to model results in a consistent manner by applying a simple correction. Apart from this, total retrieval errors are dominated by instrumental noise. The typical single measurement precision of temperature and NO abundances are 540 K and 1030%, respectively, for high Ap values, increasing to 3070 K for Tk and 2050% for NO VMR for low Ap conditions. Temperature and NO profiles observed under auroral conditions are rather insensitive to smoothing errors related to the mapping of a priori profile shapes. However, for extra-polar and low Ap conditions, a potential systematic bias in the retrieved nighttime temperature and NO profiles related to smoothing errors has been identified from a comparison to Thermosphere Ionosphere Mesosphere Electrodynamics General Circulation Model (TIME-GCM) simulations. We have constructed a solar minimum monthly climatology of thermospheric temperature and NO from MIPAS observations taken during 20082009. MIPAS temperature distributions agree well, on average, with the Mass Spectrometer and Incoherent Scatter radar model (NRLMSISE-00), but some systematic differences exist. MIPAS temperatures are generally colder than NRLMSISE-00 in the polar middle thermosphere (mainly in the summer polar region) by up to 40 K; and are warmer than NRLMSISE-00 in the lower thermosphere around 120125 km by 1040 K. Thermospheric NO daytime distributions agree well with the Nitric Oxide Empirical Model (NOEM), based on Student Nitric Oxide Explorer (SNOE) observations. A comparison of MIPAS NO number density with the previous climatology for the declining phases of the solar cycle based on HALOE and SME data shows that MIPAS is generally larger with values ranging from 10 to 40%, except in the auroral region and at the equatorial latitudes above 130 km where the MIPAS/HALOE+SME ratio varies from 1.6 to 2. Day-night differences in MIPAS NO show daytime enhancements of up to 140% in the tropical and midlatitudes middle thermosphere. In the lower thermosphere, the diurnal amplitude is smaller and NO concentrations are generally higher during night by about 1030%, particularly in the auroral regions.
Headache is the most common symptom of colloid cysts, Rathke cysts, and craniopharyngioma due to their location in the midline, being extra-axial and typically presenting in the parasellar region.
...Although these tumors are generally considered benign, each has its typical characteristics defined by its location and histology. These individual characteristics define whether surgery is necessary at all and if so, the preferred surgical approach and resection's totality. The histopathological findings primarily indicate that embryonic malformations-at the first glance, ectodermal in nature-cause these tumors.
Due to the fact that these disturbances occur at the boundary between ectodermal stomodeum and endodermal cephalogaster, however, does leave some doubts.
The origin and maintenance of a plastidic tandem repeat next to the
trn
F
UUC
gene were analyzed in the genus
Boechera
in a phylogenetic context and were compared to published analogous examples that ...emerged in parallel in the Asteraceae and Juncaceae, respectively. Although we identified some features common to these taxonomic groups with respect to structure and origin of the region, obvious differences were encountered, which argue against a specific mechanism or evolutionary principle underlying the parallel origin and maintenance of the
trn
F‐tandem repeats in those families. In contrast to the situation in the Asteraceae, no reciprocal recombinant repeat types have been observed in the Brassicaceae. Forty copy types, classified into three groups, were isolated from 103 chloroplast haplotypes of
Boechera
and it was demonstrated that they are composed of four subregions of various origins. We discuss various mutation mechanisms such as DNA replication slippage, and inter‐ and intrachromosomal recombination which were reported to mediate variation in copy numbers and other types of observed sequence length polymorphism. It is shown that the observed molecular structure of the tandem repeat region did not fully fit the particular patterns expected under a scenario of evolution including any of the known mechanisms. Nevertheless, it appeared that intermolecular unequal crossing‐over is most likely the driving force in the evolution of this tandem repeat. However, it remains to be explained, why no reciprocal recombinant copy types have been observed. The reconstructed phylogenetic relationships among copies reflected different evolutionary scenarios as follows: (1) A single and ancient origin of copies pre‐dates the radiation of
Boechera
. (2) Parallel expansion and shortening of the tandem repeat within different
Boechera
lineages. (3) Conservation of the first copy, as it was the only one present in all chloroplast haplotypes.
PDF
