The Basic Course: A Means of Protecting the Speech Communication Discipline

During the summer of 1995, Spectra included articles and news items regarding speech communication programs designated for elimination. Some leaders in the discipline warned that this trend would likely continue. This article argues that departments of communication, operating under federal and state requirements for communication competency, may be well advised to work toward establishing the basic course as the sole fulfillment of their institutions\u27 core requirement in communication and to plan a marketing strategy for their discipline. In addition, this paper suggests that the basic course, taught as public speaking, may be more easily defended in meeting the course requirement, as opposed to the hybrid course and other courses within that discipline

Calcium binding activity of the epidermal growth factor-like domains of the apicomplexan microneme protein EtMIC4

Microneme proteins are secreted from apicomplexan parasites during invasion of host cells and they play crucial roles in parasite-host cell adhesion. EtMIC4 is a 240 kDa transmembrane protein from Eimeria tenella that contains 31 tandemly arranged epidermal growth factor (EGF), like repeats within its extracellular domain. The majority of these repeats have calcium binding (cb) consensus sequences. Little is known about cbEGFs in apicomplexan parasites but their presence in microneme proteins suggests that they may contribute to parasite-host interactions. To investigate the potential role of cbEGFs we have expressed and correctly refolded a cbEGF triplet from EtMIC4 (cbEGF7-9) and demonstrated that this triplet binds calcium. Circular dichroism spectroscopic analysis of cbEGF7-9 demonstrates that the molecule undergoes a gradual change in conformation with increasing levels of calcium. In the presence of calcium, the triplet becomes resistant to proteolytic degradation by a variety of proteases, a characteristic feature of cbEGF repeats from higher eukaryotic proteins, such as fibrillin, suggesting that calcium binding induces the formation of a rigid conformation. Moreover, mass spectrometric mapping of the cleavage sites that are protected by calcium shows that these sites are located both close to and distant from the calcium binding sites, indicating that protection is not due to steric hindrance by calcium ions, but rather due to the overall conformation adopted by the triplet in the presence of calcium. Thus, the tandemly-arranged cbEGF repeats within EtMIC4 provide a mechanism whereby, in the calcium-rich extracellular environment, the molecule could adopt a protease-resistant, rigid structure that could favour its interaction with host cell ligands

Ice Scours in the Sediments of Glacial Lake Iroquois, Prince Edward County, Eastern Ontario

Straight or slightly curved ice scours are found in thin glacilacustrine sediment of eastern Lake Iroquois, especially near the crest of an escarpment in Prince Edward County. They are large (to 3.57 km long and 174 m wide), shallow (about 1 m deep) and oriented in a nearly westerly direction. Irregular ridges of sediment have been pushed up along the sides and at the western end of some scours. Bedrock is near the ground surface, but had little influence on the formation of the scours. Based on their shape, location and pattern, we conclude that the scours were most likely formed in shallow water of the short-lived Sydney phase of Lake Iroquois by lake ice driven by prevailing northeasterly winds from the retreating Laurentide Ice Sheet.On trouve des sillons glaciels, rectilignes ou courbes, dans des sédiments lacustres de l'est du Lac Iroquois, en particulier près du sommet d'un escarpement dans le comté de Prince Edward. Ces sillons sont larges (jusqu'à 3,57 km de longueur et 174 m de largeur), peu profonds (environ 1 m) et orientés vers l'ouest. Des bourrelets irréguliers de sédiments apparaissent en bordure et à l'extrémité ouest de quelques dépressions. Le substratrum affleure presque, mais a eu peu d'influence sur la formation des sillons. En se fondant sur leur forme, leur emplacement et leur agencement, on en conclut que les sillons ont été formés dans les eaux peu profondes du Lac Iroquois au cours de la courte phase de Sydney, par les glaces du lac poussées par les vents dominants du nord-est, en provenance de l'Inlandsis laurentidien alors en retrait.,1EZlOBbIE B0P03Zlbl B HAHOCAX 3AMEP3lilErO HP0KE3CK0r0 03EPA. TPAOCTBO nPMHU 3ZtBAPZl. BOCTOMHbM OHTAPHO. B TOHKHX JieaOBblX HaHOCaX B BOCTOi-lHOH HacTH Hpok-e3Ckoro 03epa ocoôeHHO pa/ioM c rpefiHeM KpyToro ck'JioHa rpa(|)CTBa flpnnu dnsapn MOAHO na6^ioziaTb npSMbie tum cnerka HSBHBaiolilnecn .neaoBbie 6opo3AU. OHM HMeioT fkyibunie pa3Mepw (no 3.57 KM B JWHHy H 174 M B mnpnHyi. MCAKM H opueH TnpoBanbi npenMylilecTBeHHO Ha 3anaa. HepeperyjiapHbie rpefJHH HaHocoB HaxoflflT-CJi no fjoKaM H B 3anaziHbix OKOHLiaHiiax HeKOTopwx 6opo3/j. HecMOTpa Ha TO. MTO nopo/ia HaxoziHTCfi 6^H3KO OT noBepxHocTH rpyHTa. eë B^nflnne Ha (|K>pMnpoBaHHe mix 6opo34 HeBCiHKO. Ha ocHOBaHiin (tjopMbl, pacnano*eHHfl H piicyHKa 5opo3/t /icnaeTC" BUBO/1, MTO OHH. CKOpee BCerO. f)W/lH ClpOpMHpOBaHbl B MeJIKHX BOZiaX MpOKe3CKOrO 03epa BO BpeMfl KopoTkOH (ba3bi Cn/iHeiï nozi B03,aeHCTBi(eM 03ëpnoro j\t>j\a, HaitccetiHoro /lOMHHHpyiOlilHMH CeBepOBOCTOMHhlMH BeTpaMH OT OTcTynaioUJero /laBpenTHitcKoro MaTepnKOBoro neaHHKa

Capillary condensation in one-dimensional irregular confinement

Peer reviewedPublisher PD

Zero-temperature random-field Ising model on a bilayered Bethe lattice

Peer reviewedPublisher PD

The Anisotropic Bak-Sneppen model

The Bak-Sneppen model is shown to fall into a different universality class with the introduction of a preferred direction, mirroring the situation in spin systems. This is first demonstrated by numerical simulations and subsequently confirmed by analysis of the multitrait version of the model, which admits exact solutions in the extremes of zero and maximal anisotropy. For intermediate anisotropies, we show that the spatiotemporal evolution of the avalanche has a power law `tail' which passes through the system for any non-zero anisotropy but remains fixed for the isotropic case, thus explaining the crossover in behaviour. Finally, we identify the maximally anisotropic model which is more tractable and yet more generally applicable than the isotropic system

Economics of tillage management systems in northeastern Alberta

Non-Peer ReviewedThe economic returns and riskiness of continuous barley production using four tillage management systems were compared at five sites in three soil zones in northeastern Alberta. The study used five years of data from a tillage experiment in northeastern Alberta. The four tillage systems included conventional one (C1), which leaves 5% standing stubble, conventional two (C2), which leaves 50% standing stubble, minimum-tillage (Min), and zero-tillage (ZT). Economic calculations were based on 1992 input costs and product prices. The systems were evaluated at barley prices of $46,$69, and $92 t-1, calculated with and without all risk crop insurance. Over the five sites the expected net returns were generally higher for ZT at all barley prices. Income variability was usually lower for ZT and C2 depending on the site. The study concluded that use of reduced tillage management systems by producers in northeastern Alberta could increase farm-level returns and reduce the risk of financial loss, while potentially decreasing the amount of soil erosion

Seismic Assessment of Syncrude Tailings Dyke

This paper describes the assessment of seismic risk at the Syncrude Site. It reviews the site physiographic and geologic setting and considers the site position relative to observed seismic events, strain release patterns, and main tectonic features in western Canada. Both deterministic and probabilistic approaches were employed in the seismic risk assessment. Data on seismic events that occurred between 1899 and 1985 were included in the evaluation. Of particular importance was determination of the impact on the site of a series of large earthquakes which occurred in the Nahanni area of the Northwest Territories during 1985. Hasegawa et al. (1981) attentuation relations were used for computing ground motion amplitudes at the site. The review confirmed that the seismic risk at the Syncrude Site remains low