Faculty of Arts & Science

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11,000 yrs of environmental change in the Northwest Passage; a multiproxy core record from central Parry Channel, Canadian High Arctic
(2013) Pieńkowski, Anna J.; England, John H.; Furze, Mark F.A.; Blasco, Steve; Mudie, Peta J.; MacLean, Brian
a rare paleoenvironmental archive from the understudied west-central Canadian Arctic Archipelago. Lithological, biogeochemical, and microfossil (dinoflagellate cysts, non-pollen palynomorphs, benthic and planktonic foraminifera) characteristics, in combination with a chronostratigraphy based on seventeen radiocarbon dates, show seven prominent paleoenvironmental episodes since the end of the last regional glaciation. The basal diamict (Zone I) records decoupling of previously grounded glacial ice, followed by ice-proximal conditions (Zone IIa) commencing at ~ 10.8 cal ka BP (age-depth model extrapolation). After an interval of pervasive sea-ice (Zone IIb), ice-distal conditions are established (Zone IIc). Although sparse microfossils are present in glaciomarine sediments (Zone II), noticeable biological activity with heightened abundances and diversities across all groups begins in the postglacial Zone III (10.3–10.0 cal ka BP) when planktonic foraminifera (Neogloboquadrina pachyderma) appear. As planktonics are excluded from the study area today (due to shallow inter-channel sills), this likely signals the inflow of relatively warm and saline Atlantic-derived Arctic Intermediate Water below 250 m, presumably facilitated by glacio-isostatically enhanced deglacial water depths. The subsequent Zone IV (10.0–7.0 cal ka BP), characterized by heightened biological productivity in both plankton and benthos and reduced seasonal sea-ice cover, may correspond to a previously proposed Holocene Thermal Maximum. This apparent amelioration ends by the mid Holocene (Zone V; 7.0–5.7 cal ka BP) when Arctic Intermediate Water is excluded from the study area and water depths approach modern values. High-Arctic conditions with seasonal sea-ice cover, a circulation dominated by Arctic Ocean Surface Water, and microfossil assemblages similar to modern are found from ~ 5.7 cal ka BP onwards (Zones VI–VII). As only minor environmental fluctuations are apparent during the late Holocene, shorter-term climatic episodes (e.g. Little Ice Age) are not recognized in this record.
2021 Canadian federal election, election report: Facebook use by political parties
(2022) Boulianne, Shelley; Stevens, Leanne; Mullin, Samantha; Rondeau, Caroline; El-hakim, Yaseen; Johal, Sunpreet; Mamo, Natalie
We coded Facebook posts from a four-week period beginning August 23, 2021 and ending September 20, 2021. A team of six coders were trained using a codebook that includes more than 300 variables. This report covers a handful of the variables. Coders were given a Facebook link, which they opened in one window. Then in another window, they went through an online questionnaire hosted by SoSciSurvey.
An abdominal stridulation organ in Cyphoderris (Prophalangopsidae) and concerning the systematic classification of the Ensifera (Saltatoria)
(2021-01-11) Ander, Kjell; Sander, Barbara; Judge, Kevin; translated.com
Ensiferan insects (crickets, katydids, grigs and allies) are well known for rubbing parts of their cuticle together to produce sound: a process called stridulation. In this article Swedish entomologist Kjell Ander describes a novel (at the time) stridulatory apparatus in the great grig, Cyphoderris monstrosa (Prophalangopsidae), a relict ensiferan found in the mountainous regions of western North America. Ander used preserved specimens to predict the sound-producing function of a pair of abdominal file-scraper apparatuses, although he was never able to directly test his proposed mechanism nor did he speculate as to the adaptive significance of the structures. The article concludes with a review of the systematic placement of various higher level taxa within the order Orthoptera, of which Ensifera is one suborder.
Absent animals in Patrick Deville's Kampuchéa
(2023) Epp, Marla
This article focuses on the ways in which encounters with animals, a frequent trope in travel literature, are reworked in Patrick Deville's Kampuchéa (2011) to reflect the current dire ecological situation. Deville's narrator is in South East Asia following the path of French naturalist Henri Mouhot, whose diary of his travels was published in 1868. Although the travel routes are similar and the basic components of a travel narrative remain, Mouhot's literary style is reconfigured to reflect the twenty-first-century traveller's awareness of the violent past of the region and anxiety over the future of the planet. If animals abound in Mouhot's diary, they are remarkable in Kampuchéa primarily through their absence. Deville does not, however, occlude them from his narrative, but rather writes about them in absentia. This article studies the implications of Deville's writing about animals without any meaningful face-to-face encounters. It further considers the repercussions of these lost moments of exchange and argues that Deville's commitment to writing about animals, even those who are absent, works to keep their looming extinction at the forefront of readers' minds.
Absolute pitch in boreal chickadees and humans: exceptions that test a phylogenetic rule
(2010) Weisman, Ronald G.; Balkwill, Laura-Lee; Hoeschele, Marisa; Moscicki, Michele; Bloomfield, Laurie L.; Sturdy, Christopher B.
This research examined generality of the phylogenetic rule that birds discriminate frequency ranges more accurately than mammals. Human absolute pitch chroma possessors accurately tracked transitions between frequency ranges. Independent tests showed that they used note naming (pitch chroma) to remap the tones into ranges; neither possessors nor nonpossessors were accurate at octave (pitch height) naming. Boreal chickadees discriminated frequency ranges less accurately than other birds; they tracked reward across several lower frequency ranges but failed at frequencies over 4000 Hz. The results revealed the error of describing species differences solely in terms of their discrimination of frequency ranges. Exceptions to the rule disappear when the rule is restated in terms of underlying mechanism: birds are superior to mammals in the ability to use absolute pitch height perception to discriminate pitches and ranges of pitches.
Absorption of electromagnetic waves in sandstone saturated with brine and nanofluids for application in enhanced oil recovery
(2019) Ali, Hassan; Soleimani, Hassan; Yahya, Noorhana; Lorimer, Shelley; Sabet, Maziyar; Demiral, Birol M. R.; Adebayo, Lawal Lanre
In this study, scattering parameters of sandstone saturated with brine and nanofluids are evaluated experimentally and numerically for the application in enhanced oil recovery (EOR). Zinc Oxide (ZnO) and Bismuth ferrite BiFeO3 (BFO) nanoparticles were synthesized via facile sol–gel method followed by nanofluid preparation. Sandstone samples were saturated with brine and nanofluids for 48 h. Electromagnetic properties of the saturated sandstones were measured experimentally using the vector network analyzer, and the scattering parameters of the samples were studied numerically by finite element method. BFO displayed higher permeability value of 1.52 and 1.30, as well as superior dielectric permittivity value 11.55 and 6.59 for real and imaginary parts, respectively. In addition, the sandstone saturated with BFO showed an impressive reflection loss (RL) value of −9.77 dB at high frequency. Conclusively, BiFeO3 nanofluids showed the best potential to enhance oil recovery which can be accredited to the superior electromagnetic properties of BFO.
Abundance of the parasitic copepod Caligus elongatus on wild pollock near commercial salmonid net-pens
(1996) Shaw, Ross; Opitz, M.
Between July and December 1993, wild pollock Pollachius virens collected near salmonid net‐pens on the Atlantic coast of Maine in the United States were examined for parasitic copepods of the family Caligidae to determine the role of pollock as host reservoirs. Only Caligus elongatus was detected on 1,456 pollock sampled. Most pollock (97.39%) had two or fewer sea lice per fish. A maximum prevalence (percent of fish infested) of 50%, an abundance (average number per fish) of 0.9, and an intensity (average number per infested fish) of L79 were recorded. Only one larval C. elongatus was found. No seasonal or geographic trends in infestation statistics were observed.
Abuse histories and attributions of sexual offenders
(2011) Jung, Sandy; Carlson, Elizabeth; Jung, Sandy
The current study is an exploratory study examining the relationship between the abuse histories of 89 sexual offenders and the constructs of locus of control, sexual attitudes, general empathy, and denial. Of the 89 offenders, 14.6% were sexually abused, 13.5% physically abused, and 9% both sexually and physically abused, with 61.5% having no abuse history. Analyses indicated that motivation to change was higher for abused versus non‐abused offenders, and that those who were sexually abused had significantly more cognitive distortions about children than those who experienced physical abuse. Although no differences emerged in locus of control scores, our findings indicated that physically abused offenders were more able to take on the perspective of others than those who have not experienced physical abuse. The findings provide several avenues to pursue in examining the longstanding effects of abuse in the thinking and cognitions of sexual offenders.
Academic procrastination: the pattern and correlates of behavioural postponement
(2006) Powell, Russell A.; Howell, Andrew J.; Watson, David; Buro, Karen
Using a series of computer-based assignments, we examined whether students’ submission patterns revealed a hyperbolic pattern of temporal discounting, such that few assignments are submitted far ahead of the deadline and submission of assignments accelerates at an increasing rate as the deadline becomes imminent. We further examined whether variables related to self-regulation – namely, self-reported procrastination, implementation intentions, say-do correspondence, and perceived academic control – correlated with behavioural postponement. Results revealed strong behavioural evidence of temporal discounting, especially among those who identified themselves as procrastinators. Among the self-regulation measures, only say-do correspondence consistently correlated with procrastination.
Academics in practice: moving beyond appreciation
(2022) Cowling, Erin; Garza, Ana Karen Rodas
In this short article, a professor and her student reflect on an ongoing project that brings them into close contact with theatrical adaptations. They discuss the ups and downs of working closely with Sor Juana’s Los empeños de una casa and Mexican actor Fernando Villa Proal of EFE TRES Teatro throughout the pandemic that started in early 2020 and has extended long into 2021. The piece also includes interview materials from theater practitioners who are interested in the overlap between theater and research. These are just some of the conclusions and suggestions that they have arrived at throughout this process, with an aim to bring academic and artistic practices into closer alignment.
The account of Thoulis, king of Egypt, in the Chronographia of John Malalas
(2014) Garstad, Benjamin
Thoulis first appears in the sixth-century chronicle of John Malalas. It has been suggested that his name is a corruption of the material found in the traditional Egyptian king-lists, but it seems more likely that he and the narrative associated with him are a fiction of more recent invention.Thoulis is modeled on Sesostris, Osiris, and Alexander the Great and the narrative of his exploits alludes to the stories of these figures. The focus of this narrative is an oracle which deflates the king’s arrogance and obliquely prophesies the doctrine of the Trinity. This oracle is consistent with the exploitation of ostensibly genuine oracles in the pagan-Christian polemics of the fourth century. Indeed, the account of Thoulis as a whole seems to have been drafted to advance the Christian position in this debate, apparently by one Bouttios in the late fourth century.
The Achaemenid Persian empire in the west and Persian-period Yehud
(2018) Ristau, Kenneth A.
The disruption and caesura caused by the destruction of Jerusalem in 587 BCE are not easily overstated. In addition to precipitating severe ideological tremors that undermined the traditional political and religious claims of Jerusalem's inviolability and Yahweh's perpetual support for the house of David, the architectonic and demographic evisceration of the city and its environs as well as the concomitant collapse of the kingdom of Judah were undeniably dramatic. In the wake of destruction and collapse, Judean society splintered. On the one hand, the Babylonian campaigns in 597 and 587 produced exiles and refugees, which created or added to Diaspora communities throughout the greater Near East that had been growing and developing since the Neo-Assyrian period (ca. 732-604 BCE). On the other hand, the remnants left in the land coalesced into two distinct enclaves: one in Benjamin, centered on Mizpah, and a second in the highlands south of Jerusalem. These enclaves consisted of a few landholding families, an impoverished populace, and disenfranchised refugees with tribal sheikhs, clan chiefs, and family heads as the local leadership.
Acute fluoxetine exposure alters crab anxiety-like behaviour, but not aggressiveness
(2016) Hamilton, Trevor; Kwan, Garfield T.; Gallup, Joshua; Tresguerres, Martin
Aggression and responsiveness to noxious stimuli are adaptable traits that are ubiquitous throughout the animal kingdom. Like vertebrate animals, some invertebrates have been shown to exhibit anxiety-like behaviour and altered levels of aggression that are modulated by the neurotransmitter serotonin. To investigate whether this influence of serotonin is conserved in crabs and whether these behaviours are sensitive to human antidepressant drugs; the striped shore crab, Pachygrapsus crassipes, was studied using anxiety (light/dark test) and aggression (mirror test) paradigms. Crabs were individually exposed to acute doses of the selective serotonin reuptake inhibitor, fluoxetine (5 or 25 mg/L), commonly known as Prozac®, followed by behavioural testing. The high dose of fluoxetine significantly decreased anxiety-like behaviour but had no impact on mobility or aggression. These results suggest that anxiety-like behaviour is more sensitive to modulation of serotonin than is aggressiveness in the shore crab.
An adaptive method for statistical detection with applications to drug discovery
(2003) Zhu, Mu; Chipman, Hugh A.; Su, Wanhua
Researchers have tried to tackle various statistical detection problems using state-of-the-art classification techniques but are often disappointed at the results. The reason is two-fold. First of all, as classification problems, these statistical detection problems are heavily unbalanced: the class of interest is rare in the training data; an overwhelming majority of the training data belong to what can be called a background class. A primary example is drug discovery, where most of the chemical compounds in the data set are inactive whereas the goal is to detect a small number of active compounds. Secondly, the goal of statistical detection is fundamentally different from that of classification, making misclassification rate the wrong criterion to focus on. In this article, we develop an adaptive method for statistical detection and demonstrate that it can be an effective tool for drug discovery.
Adjustable methacrylate porous monolith polymer layer open tubular silica capillary microextraction for the determination of polycyclic aromatic hydrocarbons
(2016) Mugo, Samuel; Huybregts, Lauren; Mazurok, James
A novel adjustable porous polymer monolith layer open tubular silica capillary microextraction (PLOT-ME) device was fabricated by thermal polymerization of a poly(glycidylmethacrylate-co-ethylene glycol dimethacrylate) (GMA-co-EDMA) polymer film (∼20 µm) within a 250 µm internal diameter silica capillary initiated with 4,4′-azobis(4-cyanopentanoyl chloride). The polymer film thickness and morphology were controlled by the polymerization time and temperature. The length of the microextraction platform immersed in the sample was adjusted by the sample concentration and sample matrix. Furthermore, since the microextraction platform performance typically degraded with use, the PLOT-ME device affords a new microextraction zone that may be exposed by cleaving off the end. This ability significantly reduces the cost of microextraction for academic and research environments. The performance of the PLOT-ME device was tested for microextraction of polycyclic aromatic hydrocarbons (PAHs): naphthalene, 2,6-dimethylnaphthalene, anthracene, 9-methylanthracene, and phenanthrene in aqueous media. Linear calibration curves for the PAHs were obtained with correlation coefficients near unity and relative standard deviations from 2 to 20% for PAH standards from 100 to 0.1 µg/L. The limits of detection for the PAHs were between 0.02 and 0.06 µg/L, while the recoveries were from 97 to 104% in lake water. The precision between different PLOT-ME devices was 11%.
Adolescent sexuality and the changing romance novel market
(1994) Bereska, Tami
After initial success, the adolescent series romance genre rapidly declined in the literary market during the 1980s. This research explores that decline through a comparative content analysis with other romance genres. Results suggest a key factor to be the relative lack of sexuality in the content of the adolescent series romances. Given the changing socio-sexual environment of adolescent girls in the 1980s, the adolescent series romances became increasingly remote from girls' own life experiences. Implications warranting further analysis include the salience and acceptability of sexuality in their daily lives, as well as their resistance to its denial.
Adsorption of selected heavy metals on modified nano cellulose
(2016) Madivoli, Edwin S.; Kareru, Patrick G.; Gachanja, Anthony N.; Mugo, Samuel; Murigi, Martin K.; Kairigo, P. K.; Kipyegon, Cheruiyot; Mutembei, Jackson K.; Njonge, Francis K.
Cellulose is an inexpensive, renewable, bio-based and an abundant raw material suitable for the development of filter membranes for water purification. This is because it has numerous functional groups that afford ease of modification to create active surfaces upon chemical modification. In this study, cellulose was isolated from two abundant biomasses, namely, Eichhornia crassipes and Cyperus papyrus using the soda process followed by bleaching with peracetic acid. The percent yield of cellulose nanofibrils (CNF) obtained from E. crassipes and C. papyrus was found to be 31.64 ± 1.46% and 29.55 ± 0.64% respectively. The degree of crystallinity and crystal sizes were calculated to be 71.42% and 0.059 nm for E. crassipes and 46.15% and 0.068 nm for C. papyrus respectively. The FT-IR absorption of the carbonyl functional group of an ester indicated that effective esterification of cellulose using citric acid was obtained when cellulose nanofibrils to citric acid ratio was 1:1. From batch adsorption studies, the capacity for citric acid modified cellulose to remove heavy metals was determined to be 8.36 mg/g Zn2+, 18.06 mg/g Cu2+, 42.69 mg/g Cd2+ and 21.64 mg/g Pb2+. In comparison to the % adsorption using unmodified cellulose of less than 5%, the heavy metals adsorption using modified nanocellulose materials were 86.47% Pb2+, 85.20% Cd2+, 77.40% Cu2+, and 70.04% Zn2+. From these results, it was concluded that modified cellulose could be used as a low cost adsorbent for removal of heavy metals and that development of household water filtration units using modified cellulose could be exploited.
Advances in Titicaca basin archaeology
(2006) Valdez, Lidio M.
This edited volume explores the ancient history of the Andean Altiplano region. The editors, especially Stanish and Aldenderfer, have been working in the south central Andean region for more than a decade and have established themselves as leading scholars of the archaeology of the Altiplano. The volume consists of eighteen chapters, arranged in chronological order, which were written by several scholars who present the results of various field studies carried out in the Titicaca Basin over the years.
Affective blindsight in the absence of input from face processing regions in occipital-temporal cortex
(2017) Striemer, Christopher; Whitwell, Robert L.; Goodale, Melvyn
Previous research suggests that the implicit recognition of emotional expressions may be carried out by pathways that bypass primary visual cortex (V1) and project to the amygdala. Some of the strongest evidence supporting this claim comes from case studies of “affective blindsight” in which patients with V1 damage can correctly guess whether an unseen face was depicting a fearful or happy expression. In the current study, we report a new case of affective blindsight in patient MC who is cortically blind following extensive bilateral lesions to V1, as well as face and object processing regions in her ventral visual stream. Despite her large lesions, MC has preserved motion perception which is related to sparing of the motion sensitive region MT+ in both hemispheres.
Affinity crystallography: a new approach to extracting high-affinity enzyme inhibitors from natural extracts
(2016) Aguda, Adeleke H.; Lavallee, Vincent; Cheng, Ping; Bott, Tina; Meimetis, Labros G.; Law, Simon; Nguyen, Nham T.; Williams, David E.; Kaleta, Jadwiga; Villanueva, Ivan; Davies, Julian; Andersen, Raymond J.; Brayer, Gary D.; Brömme, Dieter
Natural products are an important source of novel drug scaffolds. The highly variable and unpredictable timelines associated with isolating novel compounds and elucidating their structures have led to the demise of exploring natural product extract libraries in drug discovery programs. Here we introduce affinity crystallography as a new methodology that significantly shortens the time of the hit to active structure cycle in bioactive natural product discovery research. This affinity crystallography approach is illustrated by using semipure fractions of an actinomycetes culture extract to isolate and identify a cathepsin K inhibitor and to compare the outcome with the traditional assay-guided purification/structural analysis approach. The traditional approach resulted in the identification of the known inhibitor antipain (1) and its new but lower potency dehydration product 2, while the affinity crystallography approach led to the identification of a new high-affinity inhibitor named lichostatinal (3). The structure and potency of lichostatinal (3) was verified by total synthesis and kinetic characterization. To the best of our knowledge, this is the first example of isolating and characterizing a potent enzyme inhibitor from a partially purified crude natural product extract using a protein crystallographic approach.

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