Dispelling the myths of online education: learning via the information superhighway

There continues to be a perception that online education is inferior to traditional education. In the U.S. online learning is more developed than in the U.K. This paper provides insights into a U.S. provision and takes a close look at what are perceived as weaknesses of on line learning and argues that these are not necessarily inherent weaknesses of this form of educational delivery. Then, results of two major studies, undertaken in the U.S. are provided comparing the effectiveness of online education to traditional education as perceived by current MBA students and past graduates. Results of these studies suggest that students of MBA modules and MBA graduates perceive the quality and effectiveness of online education to be similar to, if not higher than, the quality and effectiveness of traditional modules and programmes

Transcriptional Evaluation of the Ductus Arteriosus at the Single-Cell Level Uncovers a Requirement for Vim (Vimentin) for Complete Closure

ObjectiveFailure to close the ductus arteriosus, patent ductus arteriosus, accounts for 10% of all congenital heart defects. Despite significant advances in patent ductus arteriosus management, including pharmacological treatment targeting the prostaglandin pathway, a proportion of patients fail to respond and must undergo surgical intervention. Thus, further refinement of the cellular and molecular mechanisms that govern vascular remodeling of this vessel is required.MethodsWe performed single-cell RNA-sequencing of the ductus arteriosus in mouse embryos at E18.5 (embryonic day 18.5), and P0.5 (postnatal day 0.5), and P5 to identify transcriptional alterations that might be associated with remodeling. We further confirmed our findings using transgenic mouse models coupled with immunohistochemistry analysis.ResultsThe intermediate filament vimentin emerged as a candidate that might contribute to closure of the ductus arteriosus. Indeed, mice with genetic deletion of vimentin fail to complete vascular remodeling of the ductus arteriosus. To seek mechanisms, we turned to the RNA-sequencing data that indicated changes in Jagged1 with similar profile to vimentin and pointed to potential links with Notch. In fact, Notch3 signaling was impaired in vimentin null mice and vimentin null mice phenocopies patent ductus arteriosus in Jagged1 endothelial and smooth muscle deleted mice.ConclusionsThrough single-cell RNA-sequencing and by tracking closure of the ductus arteriosus in mice, we uncovered the unexpected contribution of vimentin in driving complete closure of the ductus arteriosus through a mechanism that includes deregulation of the Notch signaling pathway

Books

Current Ocular Therapy. Ed. by F. T. Fraunfelder, F. Hampton Roy and S. Martha Meyer. Pp. xiii + 792. Illustrated. £55. Nonhmead: WB Saunders. 1989.Dysfunctional Uterine Bleeding and Menorrhagia. Bailliere's Clinical Obstetrics and Gynaecolcgy: International Practice and Research, June 1989. Ed. by J. O. Drife. Pp. 217 + 428. Illustrated. £18,50. Northmead: WE Saunders.1989.Treatment of Cancer. 2nd ed. Ed. by Karol Sikora and Keith E. Halnan. Pp. ix + 916. Illustrated. Price £99,50. London: Chapman and Hall Medical. 1990.Ocular Syndromes and Systemic Diseases. 2nd edition. Ed. by F. Hampton Roy. Pp. xlvii + 470. £40. Northmead: WE Saunders. 1989.Non-invasive Cardiac Imaging. British Medical Bulletin. Vol. 45, No. 4. Ed. by D. G. Gibson. Pp. 830 + 1109. Illustrated. £25 (UK) or £31,50 (overseas). New York: Churchill Livingstone. 1989.Laparoscopic Surgery. Bailliere's Clinical Obstetrics and Gynaecology: International Practice and Research, September 1989. Ed. by C. J. G. Sunon. Pp. 429 + 686. Illustrated. £18,50. Northmead: WB Saunders. 1989.Management ofMinor Head Injuries. Ed. by I. J. Swann and D. W. Yates. Pp. x + 102. Illustrated: £14,95. Hampshire: Chapman & Hall Medical. 1989.ABC of Child Abuse. Ed. by Roy Meadow. Pp. 59. Illustrated. London: BMJ. 1989.The Facts of Life. Ed. by Marina Petropulos. Pp. 1 + 222. Illustrated. R19,95 exc!. GST. Cape Town: Tafelberg. 1990.Physical Examination of the Heart and Circulation. 2nd ed. Ed. by Joseph K. Perloff. Pp. viii + 292. Illustrated. £17,95. Northmead: WB Saunders. 1989.Growth Regulation of Thyroid Gland and Thyroid Tumours: Frontiers ofHormone Research. Vo!. 18. Ed. by P. E. Goretzki, and H. D. Roher. Pp. viii + 163. Illustrated. £68,80. Basel: S. Karger. 1989.Topical Diagnosis in Neurology: Anatomy, Physiology, Signs, Symptoms. 2nd revised ed. Ed. by P. Duus. Pp. x + 337. Illustrated. DM 370. Stungart: Georg Thieme Verlag. 1989

Rapid and Repeatable Shifts in Life-History Timing of \u3ci\u3eRhagoletis pomonella\u3c/i\u3e (Diptera: Tephritidae) Following Colonization of Novel Host Plants in the Pacific Northwestern United States

Host shifts of phytophagous insect specialists to novel plants can result in divergent ecological adaptation, generating reproductive isolation and potentially new species. Rhagoletis pomonellafruit flies in eastern North America underwent a host shift ~160 ya from native downy hawthorn (Crataegus mollis) to introduced, domesticated apple (Malus domestica). Divergent selection on diapause phenology related to the earlier fruiting time of apples versus downy hawthorns resulted in partial allochronic reproductive isolation between the fly races. Here, we test for how rapid and repeatable shifts in life-history timing are driving ecological divergence of R. pomonella in the Pacific Northwestern USA. The fly was introduced into the region via larval-infested apples 40–65 ya and now attacks native black hawthorn (Crataegus douglasii) and introduced ornamental hawthorn (Crataegus monogyna), in addition to early- and late-maturing apple varieties in the region. To investigate the life-history timing hypothesis, we used a field-based experiment to characterize the host-associated eclosion and flight activity patterns of adults, and the feeding times of larvae at a field site in Vancouver, Washington. We also assessed the degree to which differences in host-fruiting time generate allochronic isolation among apple-, black hawthorn-, and ornamental hawthorn-associated fly populations. We conclude that host-associated fly populations are temporally offset 24.4% to 92.6% in their seasonal distributions. Our results imply that R. pomonella possesses the capacity for rapid and repeatable shifts in diapause life history to match host-fruiting phenology, which can generate ecologically based reproductive isolation, and potentially biodiversity in the process

Atomistic modelling of large-scale metal film growth fronts

We present simulations of metallization morphologies under ionized sputter deposition conditions, obtained by a new theoretical approach. By means of molecular dynamics simulations using a carefully designed interaction potential, we analyze the surface adsorption, reflection, and etching reactions taking place during Al physical vapor deposition, and calculate their relative probability. These probabilities are then employed in a feature-scale cellular-automaton simulator, which produces calculated film morphologies in excellent agreement with scanning-electron-microscopy data on ionized sputter deposition.Comment: RevTeX 4 pages, 2 figure

Characteristics of patients with venous thromboembolism and atrial fibrillation in Venezuela

<p>Abstract</p> <p>Background</p> <p>Studies describing venous thromboembolic event (VTEE) and atrial fibrillation (AF) in South American populations are limited. The aim of this cross-sectional study was to describe the characteristics of Venezuelan patients admitted and treated for these conditions.</p> <p>Methods</p> <p>A retrospective medical record review of 1397 consecutive patients admitted to three private hospitals or clinics between January 2000 and December 2005 was performed. Data was collected on demographics, anthropometrics, hospital visit, comorbidities and treatment.</p> <p>Results</p> <p>Among 401 VTEE and 996 AF patients, men were more likely to have AF (58%) while more women experienced a VTEE (58%). Most patients were admitted via the emergency room (87%) and had only one event during the study period (83%). Common comorbidities included hypertension (46%), heart failure (17%), diabetes (12%) and congestive heart failure (11%). Characteristics of Venezuelan patients with VTEE and AF are similar to that reported in the literature for other populations.</p> <p>Conclusions</p> <p>These results provide background characteristics for future studies assessing risk factors for AF and VTEE in South American populations.</p