York University Libraries' Open Access Author Fund

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https://hdl.handle.net/10315/27520

York University Libraries (YUL) provided York researchers with access to an Open Access Author Fund from 2013 to 2023. The fund was a small pool of money that helped York faculty and students cover article processing charges (APC) they incurred when publishing in Gold open access journals. Historically, the fund covered APCs for about 20 journal articles a year.

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Now showing 1 - 20 of 73

Open Access
Altered anterior visual system development following early monocular enucleation
(Elsevier Inc., 01/11/2013) Kelly, Krista; McKetton, Larissa; Schneider, Keith; Gallie, Brenda; Steeves, Jennifer
Purpose Retinoblastoma is a rare eye cancer that generally occurs before 5 years of age and often results in enucleation (surgical removal) of the cancerous eye. In the present study, we sought to determine the consequences of early monocular enucleation on the morphological development of the anterior visual pathway including the optic chiasm and lateral geniculate nucleus. Methods A group of adults who had one eye enucleated early in life due to retinoblastoma was compared to binocularly intact controls. Although structural changes have previously been reported in late enucleation, we also collected data from one late enucleated participant to compare to our early enucleated participants. Measurements of the optic nerves, optic chiasm, optic tracts and lateral geniculate nuclei were evaluated from T1 weighted and proton density weighted images collected from each participant. Results The early monocular enucleation group exhibited overall degeneration of the anterior visual system compared to controls. Surprisingly, however, optic tract diameter and geniculate volume decreases were less severe contralateral to the remaining eye. Consistent with previous research, the late enucleated participant showed no asymmetry and significantly larger volume decreases in both geniculate nuclei compared to controls. Conclusions The novel finding of an asymmetry in morphology of the anterior visual system following long-term survival from early monocular enucleation indicates altered postnatal visual development. Possible mechanisms behind this altered development include recruitment of deafferented cells by crossing nasal fibres and/or geniculate cell retention via feedback from primary visual cortex. These data highlight the importance of balanced binocular input during postnatal maturation for typical anterior visual system morphology.
Open Access
Antiviral Strategies for Emerging Influenza Viruses in Remote Communities
(PLoS ONE, 2013-04-22) Marek, Laskowski; Amy L., Greer; Moghadas, Seyed
Background: Due to the lack of timely access to resources for critical care, strategic use of antiviral drugs is crucial for mitigating the impact of novel influenza viruses with pandemic potential in remote and isolated communities. We sought to evaluate the effect of antiviral treatment and prophylaxis of close contacts in a Canadian remote northern community. Methods: We used an agent-based, discrete-time simulation model for disease spread in a remote community, which was developed as an in-silico population using population census data. Relative and cumulative age-specific attack rates, and the total number of infections in simulated model scenarios were obtained. Results: We found that early initiation of antiviral treatment is more critical for lowering attack rates in a remote setting with a low population-average age compared to an urban population. Our results show that a significant reduction in the relative, age-specific attack rates due to increasing treatment coverage does not necessarily translate to a significant reduction in the overall arrack rate. When treatment coverage varies from low to moderate, targeted prophylaxis has a very limited impact in reducing attack rates and should be offered at a low level (below 10%) to avoid excessive waste of drugs. Conclusions: In contrast to previous work, for conservative treatment coverages, our results do not provide any convincing evidence for the implementation of targeted prophylaxis. The findings suggest that public health strategies in remote communities should focus on the wider availability (higher coverage) and timely distribution of antiviral drugs for treatment of clinically ill individuals.
Open Access
A Test for Pre-Adapted Phenotypic Plasticity in the Invasive Tree Acer negundo L.
(PLoS ONE, 2013-09-09) Lamarque, Laurent J.; Porté, Annabel; Eymeric, Camille; Lasnier, Jean-Baptiste; Lortie, Christopher; Delzon, Sylvain
Phenotypic plasticity is a key mechanism associated with the spread of exotic plants and previous studies have found that invasive species are generally more plastic than co-occurring species. Comparatively, the evolution of phenotypic plasticity in plant invasion has received less attention, and in particular, the genetic basis of plasticity is largely unexamined. Native from North America, Acer negundo L. is aggressively impacting the riparian forests of southern and eastern Europe thanks to higher plasticity relative to co-occurring native species. We therefore tested here whether invasive populations have evolved increased plasticity since introduction. The performance of 1152 seedlings from 8 native and 8 invasive populations was compared in response to nutrient availability. Irrespective of nutrients, invasive populations had higher growth and greater allocation to above-ground biomass relative to their native conspecifics. More importantly, invasive genotypes did not show increased plasticity in any of the 20 traits examined. This result suggests that the high magnitude of plasticity to nutrient variation of invasive seedlings might be pre-adapted in the native range. Invasiveness of A. negundo could be explained by higher mean values of traits due to genetic differentiation rather than by evolution of increased plasticity.
Open Access
With Great Power Comes Great Responsibility: the Importance of Rejection, Power, and Editors in the Practice of Scientific Publishing
(PLoS ONE, 2013-12-30) Lortie, Christopher; Allesina, Stefano; Aarssen, Lonnie; Grod, Olyana; Budden, Amber
Peer review is an important element of scientific communication but deserves quantitative examination. We used data from the handling service manuscript Central for ten mid-tier ecology and evolution journals to test whether number of external reviews completed improved citation rates for all accepted manuscripts. Contrary to a previous study examining this issue using resubmission data as a proxy for reviews, we show that citation rates of manuscripts do not correlate with the number of individuals that provided reviews. Importantly, externally-reviewed papers do not outperform editor-only reviewed published papers in terms of visibility within a 5-year citation window. These findings suggest that in many instances editors can be all that is needed to review papers (or at least conduct the critical first review to assess general suitability) if the purpose of peer review is to primarily filter and that journals can consider reducing the number of referees associated with reviewing ecology and evolution papers.
Open Access
Bees collect polyurethane and polyethylene plastics as novel nest materials
(Ecological Society of America, 2013-12-31) MacIvor, Scott; Moore, Andrew E.
Plastic waste pervades the global landscape. Although adverse impacts on both species and ecosystems have been documented, there are few observations of behavioral flexibility and adaptation in species, especially insects, to increasingly plastic-rich environments. Here, two species of megachilid bee are described independently using different types of polyurethane and polyethylene plastics in place of natural materials to construct and close brood cells in nests containing successfully emerging brood. The plastics collected by each bee species resembled the natural materials usually sought; Megachile rotundata, which uses cut plant leaves, was found constructing brood cells out of cut pieces of polyethylene-based plastic bags, and Megachile campanulae, which uses plant and tree resins, had brood cells constructed out of a polyurethane-based exterior building sealant. Although perhaps incidentally collected, the novel use of plastics in the nests of bees could reflect ecologically adaptive traits necessary for survival in an increasingly human-dominated environment.
Open Access
The Heterodimeric Glycoprotein Hormone, GPA2/GPB5, Regulates Ion Transport across the Hindgut of the Adult Mosquito, Aedes aegypti
(PLoS ONE, 2014-01-20) Paluzzi, Jean-Paul; Vanderveken, Mark; O’Donnell, Michael J.
A family of evolutionarily old hormones is the glycoprotein cysteine knot-forming eterodimers consisting of alpha- (GPA) and beta-subunits (GPB), which assemble by noncovalent bonds. In mammals, a common glycoprotein hormone alphasubunit (GPA1) pairs with unique beta-subunits that establish receptor specificity, forming thyroid stimulating hormone (GPA1/TSHb) and the gonadotropins luteinizing hormone GPA1/LHb), follicle stimulating hormone (GPA1/FSHb), choriogonadotropin (GPA1/CGb). A novel glycoprotein heterodimer was identified in vertebrates by genome analysis, called thyrostimulin, composed of two novel subunits, GPA2 and GPB5, and homologs occur in arthropods, nematodes and cnidarians, implying that this neurohormone system existed prior to the emergence of bilateral metazoans. In order to discern possible physiological roles of this hormonal signaling system in mosquitoes, we have isolated the glycoprotein hormone genes producing the alpha- and beta-subunits (AedaeGPA2 and AedaeGPB5) and assessed their temporal expression profiles in the yellow and dengue-fever vector, Aedes aegypti. We have also isolated a putative receptor for this novel mosquito hormone, AedaeLGR1, which contains features conserved with other glycoprotein leucine-rich repeating containing G protein-coupled receptors. AedaeLGR1 is expressed in tissues of the alimentary canal such as the midgut, Malpighian tubules and hindgut, suggesting that this novel mosquito glycoprotein hormone may regulate ionic and osmotic balance. Focusing on the hindgut in adult stage A. aegypti, where AedaeLGR1 was highly enriched, we utilized the Scanning Ion-selective Electrode Technique (SIET) to determine if AedaeGPA2/GPB5 modulated cation transport across this epithelial tissue. Our results suggest that AedaeGPA2/GPB5 does indeed participate in ionic and osmotic balance, since it appears to inhibit natriuresis and promote kaliuresis. Taken together, our findings imply this hormone may play an important role in ionic balance when levels of Na+ are limited and levels of K+ are in excess â€“ such as during the digestion and assimilation of erythrocytes following vertebrate blood-feeding by females.
Open Access
Food cravings, appetite, and snack-food consumption in response to a psychomotor stimulant drug: the moderating effect of "food-addiction"
(Frontiers, 2014-05-08) Davis, Caroline; Levitan, Robert; Kaplan, Allan S.; Kennedy, James; Carter, Jacqueline C.
There is mounting evidence that many highly processed foods have addictive properties, and that some cases of compulsive overeating resemble an addiction disorder. While support for the Yale Food Addiction Scale (YFAS) as a valid diagnostic tool has been impressive and continues to increase, to date, no research has examined the food-addiction construct in response to an actual food stimulus, and in relation to direct measures of appetite and food consumption. As part of a larger community-based study of overeating in healthy adults who were predominately overweight and obese (aged 25–50 years), 136 participants completed the YFAS, of whom 23 met the diagnostic criteria for food-addiction. They took part in a 2-day, double-blind, cross-over, single-dose drug challenge using a psychomotor stimulant (methylphenidate) and placebo. Participants were first assessed on ratings of appetite and food cravings after holding and tasting their favorite snack food, after which they were able to eat all or part of the snack, as they wished. Three separate repeated-measures analysis-of-variance procedures were carried out, each with two between-subjects factors (Diagnosis: food-addiction vs. non-food addiction) and (Sex: male vs. female) and 1 within-subjects factor (Days: drug vs. placebo). As anticipated, for all three dependent variables, there was a significant main effect for Days with a response decrease from placebo to the drug condition. With respect to food cravings and appetite ratings, results indicated that the food addiction group had significantly higher scores on both variables. For food consumption, there was a significant Days × Diagnosis interaction whereby the food-addiction group showed no food-intake suppression across days compared to the non-food-addiction group who demonstrated a significant decrease in snack-food consumption with methylphenidate. The finding that the food-addiction group was resistant to the food-intake suppression typically induced by a dopamine agonist supports evidence of dopamine signaling-strength differences in individuals with compulsive overeating compared to those without this disorder. This represents the first demonstration that individuals defined by their food-addiction status have a unique pattern of food-intake following a pharmacologic challenge with such agents.
Open Access
Amino acid-induced impairment of insulin sensitivity in healthy and obese rats is reversible
(Physiological Reports, 2014-07-04) Jeganathan, Senthure; Abdullahi, Abdikarim; Zargar, Sana; Maeda, Naomi; Riddell, Michael; ADEGOKE, OLASUNKANMI
High-protein diets (HPDs) promote weight loss but other studies implicate these diets and their constituent amino acids (AAs) in insulin resistance. We hypothesized that AA-induced insulin resistance is a temporal and reversible metabolic event. L6 myotubes were serum deprived for 4 h and then incubated in AA and/or insulin (100 nmol/L). Another group of cells was incubated overnight in AA + insulin, starved again, and then reincubated with AA and insulin. Mammalian (mechanistic) target of rapamycin complex 1 (mTORC1) signaling and glucose uptake were then measured. Healthy or insulin-resistant rats were gavaged with leucine (0.48 g/kg) and insulin sensitivity was examined. In myotubes, incubation with AA and insulin significantly (P < 0.05) increased the phosphorylation of the mTORC1 substrate ribosomal protein S6 kinase 1 (S6K1, T389) and of insulin receptor substrate 1 (IRS-1, serine residues), but suppressed insulinstimulated glucose uptake by 40% (P < 0.01). These modifications were mTORC1-dependent and were reversible. In vivo, leucine gavage reversibly increased S6K1 phosphorylation and IRS-1 serine phosphorylation 5- to 12- fold in skeletal muscle and impaired insulin tolerance of glucose (P < 0.05) in lean rats. In insulin-resistant rats, the impairment of whole blood glucose and AA metabolism induced by leucine gavage (0.001 < P < 0.05) was more severe than that observed in lean rats; however, the impairment was reversible within 24 h of treatment. If these data are confirmed in long-term studies, it would imply that the use of leucine/HPD in treating metabolic diseases is unlikely to have lasting negative effects on insulin sensitivity.
Open Access
Dataset: York University Libraries Open Access Author Fund
(2014-2018) Lupton, Aaron; Davidson, Catherine; Kosavic, Andrea
This dataset contains the list of Article Processing Charges supported by the York University Libraries Open Access Author Fund, established in 2009. Included is the journal title, publisher name, and the rate paid by York University Libraries. This list will be updated on an annual basis. Information about the fund can be found here: http://researchguides.library.yorku.ca/open_access The structure of this spreadsheet and the posting of this dataset is inspired by and modelled after the University of Ottawa Library's dataset available here: http://hdl.handle.net/10393/24935
Open Access
Validating potential energy surfaces for classical trajectory calculations
(Royal Society of Chemistry, 2015) Pritchard, Huw O.
Two possible methods for probing flaws in empirical potential energy surfaces are examined, using a simple unimolecular isomerisation as an example. One is a heuristic estimate of the degree of chaos in a vibrating molecule; the other is the energy distribution profiles at the instant of reaction. It is found that deliberate increases in the degree of computational chaos do not alter the ensemble average of intrinsic vibrational advances chaos in these trajectories.
Open Access
Attention-deficit/hyperactivity disorder in relation to addictive behaviors: a moderated-mediation analysis of personality-risk factors and sex
(Frontiers, 2015-04-20) Davis, Caroline; Cohen, Alina; Davids, Mark; Rabindranath, Alex
Introduction: Research has shown that those with attention-deficit/hyperactivity disorder (ADHD) have an increased risk for addiction disorders like alcoholism and substance abuse. What is less clear is the mechanism(s) whereby ADHD gives rise to increased engagement in addictive behaviors, and whether there are sex differences in the ADHD-addiction propensity. Both ADHD and addictions have also been associated with personality traits such as impulsivity, reward seeking, anxiousness, and negative affect. In this study, we tested a moderator-mediation model, which predicted that both sex and ADHD-symptom status would make independent contributions to the variance in personality risk and in addictive behaviors, with males, and those with diagnosed ADHD, scoring higher on both dependent variables. Our model also predicted that the effect of sex and ADHD-symptom status on addictive behaviors would be via the mediating or intervening influence of personality-risk factors. Methods: A community-based sample of young men and women took part in the study. Among these individuals, 46 had received a lifetime diagnosis of ADHD. The nondiagnosed participants were dichotomized into a high-ADHD-symptom group (n D83) and a low-symptom group (nD84). Results: We found that a high-risk personality profile may, in part, account for the relationship between ADHD symptomatology and the use/abuse of a broad range of addictive behaviors. However, we found no sex differences in personality risk for addiction or in the use of addictive behaviors; nor did sex moderate the relationships we assessed. Conclusion: While ADHD status showed a strong relationship with both dependent variables in the model, we found no difference between those who had been diagnosed with ADHD and treated with stimulants, and their high-symptom non-diagnosed/ non-treated counterparts. These results add support to claims that the treatment of ADHD with stimulant medication neither protects nor fosters the risk for substance abuse disorders.
Open Access
Factors Associated with Premenstrual Syndrome and its Different Symptom Domains among University Students in Lebanon
(ClinMed International Library, 2018-04-21) Costanian, Christy; Akiki, Zeina; Rabah, Zeinab; Daou, Safaa; Assaad, Shafika
Objectives: This study aimed to estimate the prevalence and examine the characteristics of premenstrual syndrome (PMS) among female university students. It also aimed to determine the factors associated with the affective and somatic domains of PMS. Methods: This cross sectional study was conducted among 2115 Lebanese female university students, who completed questionnaires on PMS symptoms and other factors. PMS was defined according to the “American College of Obstetricians and Gynecologists” criteria. Bivariate and multivariable associations between PMS, PMS affective and somatic domains respectively and other covariates were conducted using logistic regression. Results: Almost 63% of participants reported having PMS with 42.5% having severe PMS. The most common affective and somatic symptoms were “angry outbursts” and “abdominal bloating” respectively. Obesity, having unemployed fathers, caffeine consumption (coffee/tea), and pain medication use, and sleeping pill use were significantly associated with PMS. Among these factors, caffeine consumption, and medication use for pain were associated with PMS affective domain while BMI, caffeine consumption, and medication use for pain were related to PMS somatic domain. Conclusion: The proportion of Lebanese females with PMS and affective and somatic symptoms are notably high. These findings highlight the importance of weight management to minimize PMS symptoms.
Open Access
Altered white matter connectivity associated with visual hallucinations following occipital stroke
(Wiley, 2018-05-21) Rafique, Sara; Richards, John R.; Steeves, Jennifer
Introduction: Visual hallucinations that arise following vision loss stem from aberrant functional activity in visual cortices and an imbalance of activity across associated cortical and subcortical networks subsequent to visual pathway damage. We sought to determine if structural changes in white matter connectivity play a role in cases of chronic visual hallucinations associated with visual cortical damage. Methods: We performed diffusion tensor imaging (DTI) and probabilistic fiber tractography to assess white matter connectivity in a patient suffering from continuous and disruptive phosphene (simple) visual hallucinations for more than 2 years following right occipital stroke. We compared these data to that of healthy age-matched controls. Results: Probabilistic tractography to reconstruct white matter tracts suggests regeneration of terminal fibers of the ipsilesional optic radiations in the patient. However, arrangement of the converse reconstruction of these tracts, which were seeded from the ipsilesional visual cortex to the intrahemispheric lateral geniculate body, remained disrupted. We further observed compromised structural characteristics, and changes in diffusion (measured using diffusion tensor indices) of white matter tracts in the patient connecting the visual cortex with frontal and temporal regions, and also in interhemispheric connectivity between visual cortices. Conclusions: Cortical remapping and the disruption of communication between visual cortices and remote regions are consistent with our previous functional magnetic resonance imaging (fMRI) data showing imbalanced functional activity of the same regions in this patient (Rafique et al, 2016, Neurology, 87, 1493–1500). Long-term adaptive and disruptive changes in white matter connectivity may account for the rare nature of cases presenting with chronic and continuous visual hallucinations.
Open Access
Cost-effectiveness of a potential Zika vaccine candidate: a case study for Colombia
(Biomed Central, 2018-07-03) Shoukat, Affan; Vilches, Thomas; Moghadas, Seyed
Background: A number of Zika vaccine platforms are currently being investigated, some of which have entered clinical trials. We sought to evaluate the cost-effectiveness of a potential Zika vaccine candidate under the WHO Vaccine Target Product Profile for outbreak response, prioritizing women of reproductive age to prevent microcephaly and other neurological disorders. Methods: Using an agent-based simulation model of ZIKV transmission dynamics in a Colombian population setting, we conducted cost-effectiveness analysis with and without pre-existing herd immunity. The model was parameterized with estimates associated with ZIKV infection, risks of microcephaly in different trimesters, direct medical costs, and vaccination costs. We assumed that a single dose of vaccine provides a protection efficacy in the range 60% to 90% against infection. Cost-effectiveness analysis was conducted from a government perspective. Results: Under a favorable scenario when the reproduction number is relatively low (R0 = 2.2) and the relative transmissibility of asymptomatic infection is 10% compared with symptomatic infection, a vaccine is cost-saving (with negative incremental cost-effective ratio; ICER) for vaccination costs up to US$6 per individual without herd immunity, and up to US$4 per individual with 8% herd immunity. For positive ICER values, vaccination is highly cost-effective for vaccination costs up to US$10 (US$7) in the respective scenarios with the willingness-to-pay of US$6610 per disability-adjusted life-year, corresponding to the average per capita GDP of Colombia between 2013 and 2017. Our results indicate that the effect of other control measures targeted to reduce ZIKV transmission decreases the range of vaccination costs for cost-effectiveness due to reduced returns of vaccine-induced herd immunity. In all scenarios investigated, the median reduction of microcephaly exceeded 64% with vaccination. Conclusions: Our study suggests that a Zika vaccine with protection efficacy as low as 60% could significantly reduce the incidence of microcephaly. From a government perspective, Zika vaccination is highly cost-effective, and even cost-saving in Colombia if vaccination costs per individual is sufficiently low. Efficacy data from clinical trials and number of vaccine doses will be important requirements in future studies to refine our estimates, and conduct similar studies in other at-risk populations. Keywords: Zika, Microcephaly, Vaccination, Agent-based modeling, Cost-effectiveness
Open Access
The fast contribution of visual-proprioceptive discrepancy to reach aftereffects and proprioceptive recalibration
(PLOS, 2018-07-17) Ruttle, Jennifer E.; 't Hart, Bernard; Henriques, Denise
Adapting reaches to altered visual feedback not only leads to motor changes, but also to shifts in perceived hand location; “proprioceptive recalibration”. These changes are robust to many task variations and can occur quite rapidly. For instance, our previous study found both motor and sensory shifts arise in as few as 6 rotated-cursor training trials. The aim of this study is to investigate one of the training signals that contribute to these rapid sensory and motor changes. We do this by removing the visuomotor error signals associated with classic visuomotor rotation training; and provide only experience with a visual-proprioceptive discrepancy for training. While a force channel constrains reach direction 30o away from the target, the cursor representing the hand unerringly moves straight to the target. The resulting visual-proprioceptive discrepancy drives significant and rapid changes in no-cursor reaches and felt hand position, again within only 6 training trials. The extent of the sensory change is unexpectedly larger following the visual-proprioceptive discrepancy training. Not surprisingly the size of the reach aftereffects is substantially smaller than following classic visuomotor rotation training. However, the time course by which both changes emerge is similar in the two training types. These results suggest that even the mere exposure to a discrepancy between felt and seen hand location is a sufficient training signal to drive robust motor and sensory plasticity.
Open Access
Anaphase Chromosomes in Crane-Fly Spermatocytes Treated With Taxol (Paclitaxel) Accelerate When Their Kinetochore Microtubules Are Cut: Evidence for Spindle Matrix Involvement With Spindle Forces
(Frontiers, 2018-07-24) Forer, Arthur; Sheykhani, Rozhan; Berns, Michael
Various experiments have indicated that anaphase chromosomes continue to move after their kinetochore microtubules are severed. The chromosomes move poleward at an accelerated rate after the microtubules are cut but they slow down 1–3 min later and move poleward at near the original speed. There are two published interpretations of chromosome movements with severed kinetochore microtubules. One interpretation is that dynein relocates to the severed microtubule ends and propels them poleward by pushing against non kinetochore microtubules. The other interpretation is that components of a putative “spindle matrix” normally push kinetochore microtubules poleward and continue to do so after the microtubules are severed from the pole. In this study we distinguish between these interpretations by treating cells with taxol. Taxol eliminates microtubule dynamics, alters spindle microtubule arrangements, and inhibits dynein motor activity in vivo. If the dynein interpretation is correct, taxol should interfere with chromosome movements after kinetochore microtubules are severed because it alters the arrangements of spindle microtubules and because it blocks dynein activity. If the “spindle matrix” interpretation is correct, on the other hand, taxol should not interfere with the accelerated movements. Our results support the spindle matrix interpretation: anaphase chromosomes in taxol-treated crane-fly spermatocytes accelerated after their kinetochore microtubules were severed.
Open Access
Conservation Genomics of the Declining North American Bumblebee Bombus terricola Reveals Inbreeding and Selection on Immune Genes
(Frontiers Media, 2018-08-10) Kent, Clement; Dey, Alivia; Patel, Harshilkumar; Tsvetkov, Nadejda; Tiwari, Tanushree; MacPhail, Victoria J.; Gobeil, Yann; Harpur, Brock; Gurtowski, James; Schatz, Michael; Colla, Sheila R.; Zayed, Amro
The yellow-banded bumblebee Bombus terricola was common in North America but has recently declined and is now on the IUCN Red List of threatened species. The causes of B. terricola’s decline are not well understood. Our objectives were to create a partial genome and then use this to estimate population data of conservation interest, and to determine whether genes showing signs of recent selection suggest a specific cause of decline. First, we generated a draft partial genome (contig set) for B. terricola, sequenced using Pacific Biosciences RS II at an average depth of 35×. Second, we sequenced the individual genomes of 22 bumblebee gynes from Ontario and Quebec using Illumina HiSeq 2500, each at an average depth of 20×, which were used to improve the PacBio genome calls and for population genetic analyses. The latter revealed that several samples had long runs of homozygosity, and individuals had high inbreeding coefficient F, consistent with low effective population size. Our data suggest that B. terricola’s effective population size has decreased orders of magnitude from pre-Holocene levels. We carried out tests of selection to identify genes that may have played a role in ameliorating environmental stressors underlying B. terricola’s decline. Several immune-related genes have signatures of recent positive selection, which is consistent with the pathogen-spillover hypothesis for B. terricola’s decline. The new B. terricola contig set can help solve the mystery of bumblebee decline by enabling functional genomics research to directly assess the health of pollinators and identify the stressors causing declines.
Open Access
Transnational pharmacogovernance: emergent patterns in the jazz of pharmaceutical policy convergence
(Biomed Central, 2018-08-22) Wiktorowicz, Mary; Moscou, Kathy; Lexchin, Joel
Background: As a transnational policy network, the International Council for Harmonization of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH) aligns international regulatory standards to address the pressures of globalization on the pharmaceutical industry and increase access to new medicines. Founding ICH members include regulators and pharmaceutical industry trade associations in the European Union, the United States and Japan. In this paper we explore the manner in which state interdependence fosters the conditions for regulatory harmonization by tracing the underlying parallels between ICH and member state pharmacogovernance to clarify emergent patterns in regulatory policy convergence. Results: A shift to the life cycle approach to pharmaceutical regulation corresponded with international convergence in pre-market standards as emphasis shifted to post-market standards where convergence remains unresolved. Transnational pharmacogovernance was found to concentrate regulatory authority within a coregulatory model of bilateral negotiation with pharmaceutical trade associations in defining safety and efficacy standards. Given a context of state interdependence, parallels were found between transnational and ICH member pharmacogovernance modes that guide policy development. Divergent modes of state regulatory governance that re-calibrate perceptions of risk and risk mitigation were found to coincide with post-market policy dissonance. Conclusion: Although interdependence fostered harmonization in pre-market standards and aligned with increased focus on post-market approaches, the confluence of divergent state governance modes and perceptions of risk may inspire improvisation in post-market standards. As the ICH expands to an ensemble with a greater global reach, further research is needed to clarify the manner in which interdependence shapes transnational pharmacogovernance and the conditions that foster policy convergence in the public interest. Keywords: Pharmaceutical regulation, Medicines policy, Transnational governance, Transnational regulation, Pharmacogovernance, Policy network, Policy convergence, Drug safety, Pharmacovigilance
Open Access
Thermoelectric Nanocomposite Foams Using Non-Conducting Polymers with Hybrid 1D and 2D Nanofillers
(MDPI, 2018-09-18) Aghelinejad, Mohammadmehdi; Leung, Siu Ning
A facile processing strategy to fabricate thermoelectric (TE) polymer nanocomposite foams with non-conducting polymers is reported in this study. Multilayered networks of graphene nanoplatelets (GnPs) and multi-walled carbon nanotubes (MWCNTs) are deposited on macroporous polyvinylidene fluoride (PVDF) foam templates using a layer-by-layer (LBL) assembly technique. The open cellular structures of foam templates provide a platform to form segregated 3D networks consisting of one-dimensional (1D) and/or two-dimensional (2D) carbon nanoparticles. Hybrid nanostructures of GnP and MWCNT networks synergistically enhance the material system’s electrical conductivity. Furthermore, the polymer foam substrates possess high porosity to provide ultra-low thermal conductivity without compromising the electrical conductivity of the TE nanocomposites. With an extremely low GnP loading (i.e., ~1.5 vol.%), the macroporous PVDF nanocomposites exhibit a thermoelectric figure-of-merit of ~10−3. To the best of our knowledge, this ZT value is the highest value reported for organic TE materials using non-conducting polymers and MWCNT/GnP nanofillers. The proposed technique represents an industrially viable approach to fabricate organic TE materials with enhanced energy conversion efficiencies. The current study demonstrates the potential to develop light-weight, low-cost, and flexible TE materials for green energy generation.
Open Access
Associations between mother-preschooler attachment and maternal depression symptoms: A systematic review and meta-analysis
(PLOS, 2018-10-02) Martin, Jodi; Guérin-Marion, Camille; O’Neill, Monica; Pillai Riddell, Rebecca; Bureau, Jean-François; Spiegel, Rebecca; Badovinac, Shaylea
The current study aimed to systematically review and meta-analyze concurrent and longitudinal associations between maternal depression symptoms and mother-child attachment during the preschool period (aged 2 to 7 years) as assessed using the coding systems by Cassidy and Marvin (1992) and Main and Cassidy (1988). The review was pre-registered with PROSPERO (International Prospective Register of Systematic Reviews; Registration number CRD42017073417) and was conducted in accordance with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. A total of 7,969 records were screened and 18 articles were deemed as eligible for inclusion in the review. Studies were reviewed using qualitative synthesis techniques and, where appropriate, meta-analysis. Qualitative synthesis indicated that mothers of disorganized/controlling children most consistently reported the highest levels of depressive symptoms, both concurrently and longitudinally. The association between disorganized/controlling child attachment and concurrent maternal depressive symptoms was significant (n = 1,787; g = 0.27, 95% CI [0.13,0.40]), and was not moderated by sample type, child gender, or risk of bias. Findings of a relationship between child attachment insecurity and maternal depressive symptoms must be qualified due to significant within-study heterogeneity and publication bias. Results suggest that maternal depressive symptoms may confer risk for disorganized/controlling attachment during the preschool period.

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