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Freeze Tolerance Of Cyphoderris Monstrosa (Orthoptera: Prophalangopsidae), Jantina Toxopeus, Jacqueline Lebenzon, Alexander H. Mckinnon, Brent J. Sinclair

Biology Publications

The great grig, Cyphoderris monstrosa Uhler (Orthoptera: Prophalangopsidae), is a large (20-30 mm, >1 g), nocturnal ensiferan that in habits montane coniferous forests in northwestern North America. C. monstrosa overwinters as a late-instar nymph, but its cold tolerance strategy has not previously been reported. We collected nymphs from near Kamloops, British Columbia, in late spring to determine their cold tolerance strategy. C. monstrosa nymphs were active at low temperatures until they froze at -4.6 ± 0.3 °C. The nymphs survived internal ice formation (i.e. are freeze tolerant), had a lethal temperature between -9 and -12 °C, and could survive for …

Epithelial-To-Mesenchymal Transition Leads To Disease-Stage Differences In Circulating Tumor Cell Detection And Metastasis In Pre-Clinical Models Of Prostate Cancer, Lori E. Lowes, David Goodale, Ying Xia, Carl Postenka, Matthew M. Piaseczny, Freeman Paczkowski, Alison L. Allan

Anatomy and Cell Biology Publications

Metastasis is the cause of most prostate cancer (PCa) deaths and has been associated with circulating tumor cells (CTCs). The presence of >= 5 CTCs/7.5mL of blood is a poor prognosis indicator in metastatic PCa when assessed by the CellSearch (R) system, the "gold standard" clinical platform. However, similar to 35% of metastatic PCa patients assessed by CellSearch (R) have undetectable CTCs. We hypothesize that this is due to epithelial-to-mesenchymal transition (EMT) and subsequent loss of necessary CTC detection markers, with important implications for PCa metastasis. Two pre-clinical assays were developed to assess human CTCs in xenograft models; one comparable …

Can We Predict Ectotherm Responses To Climate Change Using Thermal Performance Curves And Body Temperatures?, Brent J Sinclair, Katie E Marshall, Mary A Sewell, Danielle L Levesque, Christopher S Willett, Stine Slotsbo, Yunwei Dong, Christopher D G Harley, David J Marshall, Brian S Helmuth, Raymond B Huey

Biology Publications

Thermal performance curves (TPCs), which quantify how an ectotherm's body temperature (Tb ) affects its performance or fitness, are often used in an attempt to predict organismal responses to climate change. Here, we examine the key - but often biologically unreasonable - assumptions underlying this approach; for example, that physiology and thermal regimes are invariant over ontogeny, space and time, and also that TPCs are independent of previously experienced Tb. We show how a critical consideration of these assumptions can lead to biologically useful hypotheses and experimental designs. For example, rather than assuming that TPCs are fixed during ontogeny, one …

Winter Warming Effects On Overwinter Survival, Energy Use, And Spring Emergence Of Cerotoma Trifurcata (Coleoptera: Chrysomelidae), Emily A. Berzitis, Heather A. Hager, Brent J Sinclair, Rebecca H. Hallett, Jonathan A. Newman

Biology Publications

1. Bean leaf beetle Cerotoma trifurcata (Förster) (Coleoptera: Chrysomelidae) is a pest of soybean in the U.S.A. and is becoming a concern in Canada. The projected increase in winter temperatures under climate change could affect overwinter survival, timing of spring emergence and, ultimately, the severity of this pest.
2. We assessed the potential effects of warmer winters in field experiments performed in three consecutive years. Three warming levels were applied: (i) heated approximately 4 °C above ambient; (ii) unheated with snow cover left intact; and (iii) unheated with snow cover removed. Survival and date of emergence were assessed in all years, and …

Regulation Of Amyloid Oligomer Binding To Neurons And Neurotoxicity By The Prion Protein-Mglur5 Complex, Flavio H. Beraldo, Valeriy G. Ostapchenko, Fabiana A. Caetano, Andre L. S. Guimaraes, Giulia D. S. Ferretti, Nathalie Daude, Lisa Bertram, Katiane O. P. C. Nogueira, Jerson L. Silva, David Westaway, Neil R. Cashman, Vilma R. Martins, Vania F. Prado, Marco A. M. Prado

Anatomy and Cell Biology Publications

The prion protein (PrPC) has been suggested to operate as a scaffold/receptor protein in neurons, participating in both physiological and pathological associated events. PrPC, laminin, and metabotropic glutamate receptor 5 (mGluR5) form a protein complex on the plasma membrane that can trigger signaling pathways involved in neuronal differentiation. PrPC and mGluR5 are co-receptors also for -amyloid oligomers (AOs) and have been shown to modulate toxicity and neuronal death in Alzheimer's disease. In the present work, we addressed the potential crosstalk between these two signaling pathways, laminin-PrPC-mGluR5 or AO-PrPC-mGluR5, as well as their interplay. Herein, we demonstrated that an existing complex …

Vacht Overexpression Increases Acetylcholine At The Synaptic Cleft And Accelerates Aging Of Neuromuscular Junctions, Satoshi Sugita, Leland L. Fleming, Caleb Wood, Sydney K. Vaughan, Matheus P. S. M. Gomes, Wallace Camargo, Ligia A. Naves, Vania F. Prado, Marco A. M. Prado, Cristina Guatimosim, Gregorio Valdez

Anatomy and Cell Biology Publications

Background: Cholinergic dysfunction occurs during aging and in a variety of diseases, including amyotrophic lateral sclerosis (ALS). However, it remains unknown whether changes in cholinergic transmission contributes to age-and disease-related degeneration of the motor system. Here we investigated the effect of moderately increasing levels of synaptic acetylcholine (ACh) on the neuromuscular junction (NMJ), muscle fibers, and motor neurons during development and aging and in a mouse model for amyotrophic lateral sclerosis (ALS). Methods: Chat-ChR2-EYFP (VAChTHyp) mice containing multiple copies of the vesicular acetylcholine transporter (VAChT), mutant superoxide dismutase 1 (SOD1G93A), and Chat-IRES-Cre and tdTomato transgenic mice were used in this …

Preterm Neonatal Lateral Ventricle Volume From Three-Dimensional Ultrasound Is Not Strongly Correlated To Two-Dimensional Ultrasound Measurements, Jessica Kishimoto, Sandrine De Ribaupierre, Fateme Salehi, Walter Romano, David S. C. Lee, Aaron Fenster

Anatomy and Cell Biology Publications

The aim of this study is to compare longitudinal two-dimensional (2-D) and three-dimensional (3-D) ultrasound (US) estimates of ventricle size in preterm neonates with posthemorrhagic ventricular dilatation (PHVD) using quantitative measurements of the lateral ventricles. Cranial 2-D US and 3-D US images were acquired from neonatal patients with diagnosed PHVD within 10 min of each other one to two times per week and analyzed offline. Ventricle index, anterior horn width, third ventricle width, and thalamo-occipital distance were measured on the 2-D images and ventricle volume (VV) was measured from 3-D US images. Changes in the measurements between successive image sets …

Editorial Overview: Global Change Biology: Linking Pattern And Process To Prediction And Policy., Vladimir Koštál, Brent J Sinclair

Biology Publications

No abstract provided.

Can We Predict The Effects Of Multiple Stressors On Insects In A Changing Climate?, Sirpa Kaunisto, Laura V Ferguson, Brent J Sinclair

Biology Publications

The responses of insects to climate change will depend on their responses to abiotic and biotic stressors in combination. We surveyed the literature, and although synergistic stressor interactions appear common among insects, the thin taxonomic spread of existing data means that more multi-stressor studies and new approaches are needed. We need to move beyond descriptions of the effects of multiple stressors to a mechanistic, predictive understanding. Further, we must identify which stressor interactions, and species' responses to them, are sufficiently generalizable (i.e. most or all species respond similarly to the same stressor combination), and thus predictable (for new combinations of …

Effects Of Aging And Coronary Artery Disease On Sympathetic Neural Recruitment Strategies During End-Inspiratory And End-Expiratory Apnea, Mark B. Badrov, Sophie Lalande, T Dylan Olver, Neville Suskin, J Kevin Shoemaker

Kinesiology Publications

In response to acute physiological stress, the sympathetic nervous system modifies neural outflow through increased firing frequency of lower-threshold axons, recruitment of latent subpopulations of higher-threshold axons, and/or acute modifications of synaptic delays. Aging and coronary artery disease (CAD) often modify efferent muscle sympathetic nerve activity (MSNA). Therefore, we investigated whether CAD (n = 14; 61 ± 10 yr) and/or healthy aging without CAD (OH; n = 14; 59 ± 9 yr) modified these recruitment strategies that normally are observed in young healthy (YH; n = 14; 25 ± 3 yr) individuals. MSNA (microneurography) was measured at baseline and during …

Role Of Spinophilin In Group I Metabotropic Glutamate Receptor Endocytosis, Signaling, And Synaptic Plasticity, Andrea R. Di Sebastiano, Sandra Fahim, Henry A. Dunn, Cornelia Walther, Fabiola M. Ribeiro, Sean P. Cregan, Stephane Angers, Susanne Schmid, Stephen S. G. Ferguson

Anatomy and Cell Biology Publications

Activation of Group I metabotropic glutamate receptors (mGluRs) activates signaling cascades, resulting in calcium release from intracellular stores, ERK1/2 activation, and long term changes in synaptic activity that are implicated in learning, memory, and neurodegenerative diseases. As such, elucidating the molecular mechanisms underlying Group I mGluR signaling is important for understanding physiological responses initiated by the activation of these receptors. In the current study, we identify the multifunctional scaffolding protein spinophilin as a novel Group I mGluR-interacting protein. We demonstrate that spinophilin interacts with the C-terminal tail and second intracellular loop of Group I mGluRs. Furthermore, we show that interaction …

Increasing Nonsedentary Behaviors In University Students Using Text Messages: Randomized Controlled Trial, Emma Cotten, Harry Prapavessis

Kinesiology Publications

BACKGROUND: Sedentary behavior (SB) has been linked to many health problems such as type 2 diabetes and heart disease. Increasing the length and frequency of breaks from sitting and increasing the time spent standing and engaged in light and moderate physical activity are ways to decrease SB. Text message-based interventions have succeeded in aiding smoking cessation and increase both physical activity and healthy eating, but they have not been shown to reduce SB.

OBJECTIVE: The primary purpose of this pilot study was to determine the effectiveness of a text message-based intervention in increasing nonsedentary behaviors in university students. A secondary …

Domains Of Stip1 Responsible For Regulating Prpc-Dependent Amyloid-Β Oligomer Toxicity., Andrzej Maciejewski, Valeriy G Ostapchenko, Flavio H Beraldo, Vania F Prado, Marco A M Prado, Wing-Yiu Choy

Biochemistry Publications

Soluble oligomers of amyloid-beta peptide (AβO) transmit neurotoxic signals through the cellular prion protein (PrP(C)) in Alzheimer's disease (AD). Secreted stress-inducible phosphoprotein 1 (STIP1), an Hsp70 and Hsp90 cochaperone, inhibits AβO binding to PrP(C) and protects neurons from AβO-induced cell death. Here, we investigated the molecular interactions between AβO and STIP1 binding to PrP(C) and their effect on neuronal cell death. We showed that residues located in a short region of PrP (90-110) mediate AβO binding and we narrowed the major interaction in this site to amino acids 91-100. In contrast, multiple binding sites on STIP1 (DP1, TPR1 and TPR2A) …

Effects Of Acute And Chronic Interval Sprint Exercise Performed On A Manually Propelled Treadmill On Upper Limb Vascular Mechanics In Healthy Young Men., T Dylan Olver, Steph M Reid, Alan R Smith, Mair Zamir, Peter W R Lemon, M Harold Laughlin, J Kevin Shoemaker

Kinesiology Publications

Interval sprint exercise performed on a manually propelled treadmill, where the hands grip the handle bars, engages lower and upper limb skeletal muscle, but little is known regarding the effects of this exercise modality on the upper limb vasculature. We tested the hypotheses that an acute bout of sprint exercise and 6 weeks of training induces brachial artery (BA) and forearm vascular remodeling, favoring a more compliant system. Before and following a single bout of exercise as well as 6 weeks of training three types of vascular properties/methodologies were examined in healthy men: (1) stiffness of the entire upper limb …

Impact Of Long-Term Endurance Training Vs. Guideline-Based Physical Activity On Brain Structure In Healthy Aging, Katelyn N. Wood, Robert Nikolov, J Kevin Shoemaker

Kinesiology Publications

Brain structure is a fundamental determinant of brain function, both of which decline with age in the adult. Whereas short-term exercise improves brain size in older adults, the impact of endurance training on brain structure when initiated early and sustained throughout life, remains unknown. We tested the hypothesis that long-term competitive aerobic training enhances cortical and subcortical mass compared to middle to older-aged healthy adults who adhere to the minimum physical activity guidelines. Observations were made in 16 masters athletes (MA; 53 ± 6 years, VO2max = 55 ± 10 ml/kg/min, training > 15 years), and 16 active, healthy, and cognitively …

Ion And Water Balance In Gryllus Crickets During The First Twelve Hours Of Cold Exposure., Lauren E Des Marteaux, Brent J Sinclair

Biology Publications

Insects lose ion and water balance during chilling, but the mechanisms underlying this phenomenon are based on patterns of ion and water balance observed in the later stages of cold exposure (12 or more hours). Here we quantified the distribution of ions and water in the hemolymph, muscle, and gut in adult Gryllus field crickets during the first 12h of cold exposure to test mechanistic hypotheses about why homeostasis is lost in the cold, and how chill-tolerant insects might maintain homeostasis to lower temperatures. Unlike in later chill coma, hemolymph [Na(+)] and Na(+) content in the first few hours of …

Generation Of Organ-Conditioned Media And Applications For Studying Organ-Specific Influences On Breast Cancer Metastatic Behavior, Matthew M. Piaseczny, Graciella M. Pio, Jenny E. Chu, Ying Xia, Kim Nguyen, David Goodale, Alison Allan

Anatomy and Cell Biology Publications

Breast cancer preferentially metastasizes to the lymph node, bone, lung, brain and liver in breast cancer patients. Previous research efforts have focused on identifying factors inherent to breast cancer cells that are responsible for this observed metastatic pattern (termed organ tropism), however much less is known about factors present within specific organs that contribute to this process. This is in part because of a lack of in vitro model systems that accurately recapitulate the organ microenvironment. To address this, an ex vivo model system has been established that allows for the study of soluble factors present within different organ microenvironments. …

Associative Spike Timing-Dependent Potentiation Of The Basal Dendritic Excitatory Synapses In The Hippocampus In Vivo., Thomas K Fung, Clayton S Law, L Stan Leung

Physiology and Pharmacology Publications

Spike timing-dependent plasticity in the hippocampus has rarely been studied in vivo. Using extracellular potential and current source density analysis in urethane-anesthetized adult rats, we studied synaptic plasticity at the basal dendritic excitatory synapse in CA1 after excitation-spike (ES) pairing; E was a weak basal dendritic excitation evoked by stratum oriens stimulation, and S was a population spike evoked by stratum radiatum apical dendritic excitation. We hypothesize that positive ES pairing-generating synaptic excitation before a spike-results in long-term potentiation (LTP) while negative ES pairing results in long-term depression (LTD). Pairing (50 pairs at 5 Hz) at ES intervals of -10 …

Reproductive Arrest And Stress Resistance In Winter-Acclimated Drosophila Suzukii., Jantina Toxopeus, Ruth Jakobs, Laura V Ferguson, Tara D Gariepy, Brent J Sinclair

Biology Publications

Overwintering insects must survive the multiple-stress environment of winter, which includes low temperatures, reduced food and water availability, and cold-active pathogens. Many insects overwinter in diapause, a developmental arrest associated with high stress tolerance. Drosophila suzukii (Diptera: Drosophilidae), spotted wing drosophila, is an invasive agricultural pest worldwide. Its ability to overwinter and therefore establish in temperate regions could have severe implications for fruit crop industries. We demonstrate here that laboratory populations of Canadian D. suzukii larvae reared under short-day, low temperature, conditions develop into dark 'winter morph' adults similar to those reported globally from field captures, and observed by us …

Possible Radiation-Induced Damage To The Molecular Structure Of Wooden Artifacts Due To Micro-Computed Tomography, Handheld X-Ray Fluorescence, And X-Ray Photoelectron Spectroscopic Techniques, Madalena Kozachuk, Alexandra Suda, Lisa Ellis, Mary Walzak, Mark Biesinger, Sheila Macfie, Robert Hudson, Andrew Nelson, Ronald Martin, Arlen Heginbotham

Biology Publications

This study was undertaken to ascertain whether radiation produced by X-ray photoelectron spectroscopy (XPS), micro-computed tomography (μCT) and/or portable handheld X-ray fluorescence (XRF) equipment might damage wood artifacts during analysis. Changes at the molecular level were monitored by Fourier transform infrared (FTIR) analysis. No significant changes in FTIR spectra were observed as a result of μCT or handheld XRF analysis. No substantial changes in the collected FTIR spectra were observed when XPS analytical times on the order of minutes were used. However, XPS analysis collected over tens of hours did produce significant changes in the FTIR spectra.

Paradoxical Acclimation Responses In The Thermal Performance Of Insect Immunity., Laura V Ferguson, David E Heinrichs, Brent J Sinclair

Biology Publications

Winter is accompanied by multiple stressors, and the interactions between cold and pathogen stress potentially determine the overwintering success of insects. Thus, it is necessary to explore the thermal performance of the insect immune system. We cold-acclimated spring field crickets, Gryllus veletis, to 6 °C for 7 days and measured the thermal performance of potential (lysozyme and phenoloxidase activity) and realised (bacterial clearance and melanisation) immune responses. Cold acclimation decreased the critical thermal minimum from -0.5 ± 0.25 to -2.1 ± 0.18 °C, and chill coma recovery time after 72 h at -2 °C from 16.8 ± 4.9 to 5.2 …

Paradoxical Acclimation Responses In The Thermal Performance Of Insect Immunity., Laura V Ferguson, David E Heinrichs, Brent J Sinclair

Biology Publications

Winter is accompanied by multiple stressors, and the interactions between cold and pathogen stress potentially determine the overwintering success of insects. Thus, it is necessary to explore the thermal performance of the insect immune system. We cold-acclimated spring field crickets, Gryllus veletis, to 6 °C for 7 days and measured the thermal performance of potential (lysozyme and phenoloxidase activity) and realised (bacterial clearance and melanisation) immune responses. Cold acclimation decreased the critical thermal minimum from -0.5 ± 0.25 to -2.1 ± 0.18 °C, and chill coma recovery time after 72 h at -2 °C from 16.8 ± 4.9 to 5.2 …

Global Deletion Of Panx3 Produces Multiple Phenotypic Effects In Mouse Humeri And Femora, Deidre Caskenette, Silvia Penuela, Vanessa Lee, Kevin Barr, Frank Beier, Dale W. Laird, Katherine E. Willmore

Anatomy and Cell Biology Publications

© 2016 Anatomical Society. Pannexins form single-membrane channels that allow passage of small molecules between the intracellular and extracellular compartments. Of the three pannexin family members, Pannexin3 (Panx3) is the least studied but is highly expressed in skeletal tissues and is thought to play a role in the regulation of chondrocyte and osteoblast proliferation and differentiation. The purpose of our study is to closely examine the in vivo effects of Panx3 ablation on long bone morphology using micro-computed tomography. Using Panx3 knockout (KO) and wildtype (WT) adult mice, we measured and compared aspects of phenotypic shape, bone mineral density (BMD), …

Evaluation Of Ct Perfusion Biomarkers Of Tumor Hypoxia, Qi Qi, Timothy Pok Chi Yeung, Ting-Yim Lee, Glenn Bauman, Cathie Crukley, Laura Morrison, Lisa Hoffman, Slav Yartsev

Anatomy and Cell Biology Publications

Background Tumor hypoxia is associated with treatment resistance to cancer therapies. Hypoxia can be investigated by immunohistopathologic methods but such procedure is invasive. A non-invasive method to interrogate tumor hypoxia is an attractive option as such method can provide information before, during, and after treatment for personalized therapies. Our study evaluated the correlations between computed tomography (CT) perfusion parameters and immunohistopathologic measurement of tumor hypoxia. Methods Wistar rats, 18 controls and 19 treated with stereotactic radiosurgery (SRS), implanted with the C6 glioma tumor were imaged using CT perfusion on average every five days to monitor tumor growth. A final CT …

A Unified Analytic Framework For Prioritization Of Non-Coding Variants Of Uncertain Significance In Heritable Breast And Ovarian Cancer, Eliseos J. Mucaki, Natasha G. Caminsky, Ami M. Perri, Ruipeng Lu, Alain Laederach, Matthew Halvorsen, Joan H. M. Knoll, Peter K. Rogan

Biochemistry Publications

Background

Sequencing of both healthy and disease singletons yields many novel and low frequency variants of uncertain significance (VUS). Complete gene and genome sequencing by next generation sequencing (NGS) significantly increases the number of VUS detected. While prior studies have emphasized protein coding variants, non-coding sequence variants have also been proven to significantly contribute to high penetrance disorders, such as hereditary breast and ovarian cancer (HBOC). We present a strategy for analyzing different functional classes of non-coding variants based on information theory (IT) and prioritizing patients with large intragenic deletions.

Methods

We captured and enriched for coding and non-coding variants …

Molecular Assessment Of Bacterial Vaginosis By Lactobacillus Abundance And Species Diversity, Joke A. M. Dols, Douwe Molenaar, Jannie J. Van Der Helm, Martien P. M. Caspers, Alie De Kat Angelino-Bart, Frank H. J. Schuren, Adrianus G. C. L. Speksnijder, Hans V. Westerhoff, Jan Hendrik Richardus, Mathilde E. Boon, Gregor Reid, Henry J. C. De Vries, Remco Kort

Microbiology & Immunology Publications

Background

To date, women are most often diagnosed with bacterial vaginosis (BV) using microscopy based Nugent scoring or Amsel criteria. However, the accuracy is less than optimal. The aim of the present study was to confirm the identity of known BV-associated composition profiles and evaluate indicators for BV using three molecular methods.

Methods

Evaluation of indicators for BV was carried out by 16S rRNA amplicon sequencing of the V5-V7 region, a tailor-made 16S rRNA oligonucleotide-based microarray, and a PCR-based profiling technique termed IS-profiling, which is based on fragment variability of the 16S-23S rRNA intergenic spacer region. An inventory of vaginal …

Medial Prefrontal And Anterior Insular Connectivity In Early Schizophrenia And Major Depressive Disorder: A Resting Functional Mri Evaluation Of Large-Scale Brain Network Models, Jacob Penner, Kristen A. Ford, Reggie Taylor, Betsy Schaefer, Jean Theberge, Richard W. J. Neufeld, Elizabeth A. Osuch, Ravi S. Menon, Nagalingam Rajakumar, John M. Allman, Peter C. Williamson

Anatomy and Cell Biology Publications

Anomalies in the medial prefrontal cortex, anterior insulae, and large-scale brain networks associated with them have been proposed to underlie the pathophysiology of schizophrenia and major depressive disorder (MDD). In this study, we examined the connectivity of the medial prefrontal cortices and anterior insulae in 24 healthy controls, 24 patients with schizophrenia, and 24 patients with MDD early in illness with seed based resting state functional magnetic resonance imaging analysis using Statistical Probability Mapping. As hypothesized, reduced connectivity was found between the medial prefrontal cortex and the dorsal anterior cingulate cortex and other nodes associated with directed effort in patients …

Cost-Effectiveness Of Using A Gene Expression Profiling Test To Aid In Identifying The Primary Tumour In Patients With Cancer Of Unknown Primary., M B Hannouf, E Winquist, S M Mahmud, M Brackstone, S Sarma, G Rodrigues, P Rogan, J S Hoch, G S Zaric

Biochemistry Publications

We aimed to investigate the cost-effectiveness of a 2000-gene-expression profiling (GEP) test to help identify the primary tumor site when clinicopathological diagnostic evaluation was inconclusive in patients with cancer of unknown primary (CUP). We built a decision-analytic-model to project the lifetime clinical and economic consequences of different clinical management strategies for CUP. The model was parameterized using follow-up data from the Manitoba Cancer Registry, cost data from Manitoba Health administrative databases and secondary sources. The 2000-GEP-based strategy compared to current clinical practice resulted in an incremental cost-effectiveness ratio (ICER) of $44,151 per quality-adjusted life years (QALY) gained. The total annual-budget …

Automated Discrimination Of Dicentric And Monocentric Chromosomes By Machine Learning-Based Image Processing., Yanxin Li, Joan H Knoll, Ruth C Wilkins, Farrah N Flegal, Peter K Rogan

Biochemistry Publications

Dose from radiation exposure can be estimated from dicentric chromosome (DC) frequencies in metaphase cells of peripheral blood lymphocytes. We automated DC detection by extracting features in Giemsa-stained metaphase chromosome images and classifying objects by machine learning (ML). DC detection involves (i) intensity thresholded segmentation of metaphase objects, (ii) chromosome separation by watershed transformation and elimination of inseparable chromosome clusters, fragments and staining debris using a morphological decision tree filter, (iii) determination of chromosome width and centreline, (iv) derivation of centromere candidates, and (v) distinction of DCs from monocentric chromosomes (MC) by ML. Centromere candidates are inferred from 14 image …

The Utility Of A Protection Motivation Theory Framework For Understanding Sedentary Behavior, Tiffany S. Wong, Anca Gaston, Stefanie Dejesus, Harry Prapavessis

Kinesiology Publications

Multilevel determinants of sedentary behavior (SB), including constructs couched within evidence-based psychological frameworks, can contribute to more efficacious interventions designed to decrease sitting time. This study aimed to: (1) examine the factor structure and composition of sedentary-derived protection motivation theory (PMT) constructs and (2) determine the utility of these constructs in predicting general and leisure sedentary goal intention (GI), implementation intention (II), and self-reported SB. Sedentary-derived PMT (perceived severity, PS; perceived vulnerability, PV; response efficacy, RE; self-efficacy, SE), GI, and II constructs, and a modified SB questionnaire were completed by undergraduate students (n = 596). SE was broken into …