68 research outputs found
Finding Clio in Mid-Atlantic
When he frst stepped ashore in 1867, Mark Twain found Britainâs tiny mid-Atlantic colony of Bermuda a delightful place. Wearied by a long trip to the Holy
Land, Twain found Bermudaâs semi-tropical aesthetic immediately restful. âA few days among the breezy groves, the ïŹower
gardens, the coral caves, and the lovely vistas of blue water,â
he wrote in Te Innocents Abroad, his memoir of the trip, ââŠ
restored the energies dulled by long drowsing on the ocean.â
Twain would return habitually to Bermuda - or âBerm-o-odaâ as
his stretched it out in his Southern drawl. âYou can go to heaven
if you want to â Iâd rather stay here in Bermuda,â he would quip
from the verandah of his favourite hotel. Sadly, he failed to keep
this promise; just weeks before his death in 1910 he was stretchered in pain oïŹ the island to return to his Connecticut home. âI
have no sorrowful associations with Bermuda,â he remarked by
way of consolatio
HMCS \u3cem\u3eThiepval\u3c/em\u3e: The Accidental Tourist Destination
In the spring of 1910 an act of Parliament gave birth to the Canadian navy. What followed were four years of bitter partisan battles over whether this new service would be small and largely coastal, or whether the money was better spent in direct support of the imperial fleet. By the time war came in 1914 the fledgling service consisted of two dilapidated old cruisersâNiobe and Rainbowâacquired solely for training. During the war this navy evolved into a hodgepodge of little auxiliary vessels as it scrambled to meet the new threat from submarines. By the time the war ended, as the official naval historian Gilbert Tucker noted, Canada had nothing more than âa small ship navy.â HMCS Thiepvalâall 357 tons of herâwas borne into this emerging small ship navy in 1917. The little trawler subsequently had a brief but remarkable career in the service of Canada, and a fate that has left her as one of the West Coastâs most famous tourist sites
Social competition stimulates cognitive performance in a sex-specific manner
Social interactions are thought to be a critical driver in the evolution of cognitive ability. Cooperative interactions, such as pair bonding, rather than competitive interactions have been largely implicated in the evolution of increased cognition. This is despite competition traditionally being a very strong driver of trait evolution. Males of many species track changes in their social environment and alter their reproductive strategies in response to anticipated levels of competition. We predict this to be cognitively challenging. Using a Drosophila melanogaster model, we are able to distinguish between the effects of a competitive environment versus generic social contact by exposing flies to same-sex same-species competition versus different species partners, shown to present non-competitive contacts. Males increase olfactory learning/memory and visual memory after exposure to conspecific males only, a pattern echoed by increased expression of synaptic genes and an increased need for sleep. For females, largely not affected by mating competition, the opposite pattern was seen. The results indicate that specific social contacts dependent on sex, not simply generic social stimulation, may be an important evolutionary driver for cognitive ability in fruit flies
Oxygen-regulated gene expression in murine cumulus cells
Oxygen is an important component of the environment of the cumulusâoocyte complex (COC), both in vivo within the ovarian follicle and during in vitro oocyte maturation (IVM). Cumulus cells have a key role in supporting oocyte development, and cumulus cell function and gene expression are known to be altered when the environment of the COC is perturbed. Oxygen-regulated gene expression is mediated through the actions of the transcription factors, the hypoxia-inducible factors (HIFs). In the present study, the effect of oxygen on cumulus cell gene expression was examined following in vitro maturation of the murine COC at 2%, 5% or 20% oxygen. Increased expression of HIF-responsive genes, including glucose transporter-1, lactate dehydrogenase A and BCL2/adenovirus E1B interacting protein 3, was observed in cumulus cells matured at 2% or 5%, compared with 20% oxygen. Stabilisation of HIF1α protein in cumulus cells exposed to low oxygen was confirmed by western blot and HIF-mediated transcriptional activity was demonstrated using a transgenic mouse expressing green fluorescent protein under the control of a promoter containing hypoxia response elements. These results indicate that oxygen concentration influences cumulus cell gene expression and support a role for HIF1α in mediating the cumulus cell response to varying oxygen.Karen L. Kind, Kimberley K. Y. Tam, Kelly M. Banwell, Ashley D. Gauld, Darryl L. Russell, Anne M. Macpherson, Hannah M. Brown, Laura A. Frank, Daniel J. Peet and Jeremy G. Thompso
Finishing the euchromatic sequence of the human genome
The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers âŒ99% of the euchromatic genome and is accurate to an error rate of âŒ1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead
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