Waterloo Research

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Developing persuasive health messages for a behaviour-change-support-system that promotes physical activity
(Sage Journals, 2017-05-15) Rezai, Leila; Bassett-Gunter, Rebecca; Burns, Catherine
This paper describes the first of three experiments conducted to investigate the efficacy of a proposed persuasive mHealth messaging intervention that motivates individuals to become more physically active. In order to develop a set of persuasive health messages that can be used in the principal experiment, which examines a particular message-tailoring strategy, we conducted an online survey through Amazon Mechanical Turk. In this online study participants rated a series of health messages to indicate each message’s level of persuasiveness, as well as the message’s focus. This study was essential, as disagreements exist on how to frame persuasive health messages in the context of promoting physical activity. Among the proposed 57 messages, 14 messages rated as the most persuasive were selected for the principal experiment.
Trust in Autonomous Vehicles: The case of Tesla Autopilot and Summon
(2017-10-05) Dikmen, Murat Burns, Catherine
Autonomous driving is on the horizon. Vehicles with partially automated driving capabilities are already in the market. Before the widespread adoption however, human factors issues in the automated driving context need to be addressed. One of the key components of this is how much drivers trust in automated driving systems and how they calibrate their trust and reliance based on their experience. In this paper, we report the results of a survey conducted with Tesla drivers about their experiences with two advanced driver assistance systems, Autopilot and Summon. We found that drivers have high levels of trust in Autopilot and Summon. Trust decreased with age for Autopilot but not for Summon. Drivers who experienced unexpected behaviors from their vehicles reported lower levels of trust in Autopilot. Over time, trust in these systems increased regardless of experience. Additionally, trust was correlated with several attitudinal and behavioral factors such as frequency of use, self-rated knowledge about these systems, and ease of learning. These findings highlight the importance of trust in real world use of autonomous cars. Also, the results suggest that previous
Predictability of decaying stratified turbulence
(AIP Publishing, 2024-06-14) Diaz, Martín F.; Waite, Michael L.
Predictability of geophysical fluid dynamics at various scales remains a crucial challenge for accurate weather and climate forecasting. Following the pioneering framework established by Lorenz, numerous studies on homogeneous and isotropic turbulence have demonstrated that flows characterized by diverse scales may exhibit limited predictability. This limitation arises from the inevitable amplification of errors in the initial conditions from small scales to larger scales, even if the initial error is confined to small scales. This research investigates the predictability of freely decaying homogeneous stratified turbulence, which serves as a representative model for small-scale geophysical turbulence where rotational effects are negligible. Direct numerical simulations are employed to assess predictability by analyzing the growth of errors introduced in pairs of simulations with near-identical initial conditions; errors are modeled as the difference field of the pair. Previous studies have established a connection between the finite range of predictability and the slope of the kinetic energy spectrum. In the context of stratified turbulence, the shape of the energy spectrum exhibits a dependence on the buoyancy Reynolds number (Reb), particularly at lower values of Reb. This work conducts a comparative analysis of both the energy spectra and the error growth behavior across different regimes of stratified turbulence, encompassing a range of Reb values from O(1) to O(10)⁠. The sensitivity of the obtained results to the introduced error is investigated. Modifying the geometrical shape of the error (spherical vs cylindrical complement) and the cutoff wavenumber while maintaining the initial error kinetic energy did not significantly alter the error dynamics. The results are robust to variations in the method of error introduction.
Wearable-sensor-based classification models of faller status in older adults
(Public Library of Science, 2016-04-07) Howcroft, Jennifer; Lemaire, Edward D.; Kofman, Jonathan
Wearable sensors have potential for quantitative, gait-based, point-of-care fall risk assessment that can be easily and quickly implemented in clinical-care and older-adult living environments. This investigation generated models for wearable-sensor based fall-risk classification in older adults and identified the optimal sensor type, location, combination, and modelling method; for walking with and without a cognitive load task. A convenience sample of 100 older individuals (75.5 ± 6.7 years; 76 non-fallers, 24 fallers based on 6 month retrospective fall occurrence) walked 7.62 m under single-task and dual-task conditions while wearing pressure-sensing insoles and tri-axial accelerometers at the head, pelvis, and left and right shanks. Participants also completed the Activities-specific Balance Confidence scale, Community Health Activities Model Program for Seniors questionnaire, six minute walk test, and ranked their fear of falling. Fall risk classification models were assessed for all sensor combinations and three model types: multi-layer perceptron neural network, naïve Bayesian, and support vector machine. The best performing model was a multi-layer perceptron neural network with input parameters from pressure-sensing insoles and head, pelvis, and left shank accelerometers (accuracy = 84%, F1 score = 0.600, MCC score = 0.521). Head sensor-based models had the best performance of the single-sensor models for single-task gait assessment. Single-task gait assessment models outperformed models based on dual-task walking or clinical assessment data. Support vector machines and neural networks were the best modelling technique for fall risk classification. Fall risk classification models developed for point-of-care environments should be developed using support vector machines and neural networks, with a multi-sensor single-task gait assessment.
Attentional effects on phenomenological appearance: How they change with task instructions and measurement methods
(Public Library of Science, 2016-03-29) Anderson, Britt
It has been reported that exogenous cues accentuate contrast appearance. The empirical finding is controversial because non-veridical perception challenges the idea that attention prioritizes processing resources to make perception better, and because philosophers have used the finding to challenge representational accounts of mental experience. The present experiments confirm that when evaluated with comparison paradigms exogenous cues increase the apparent contrast. In addition, contrast appearance was also changed by simply changing the purpose of the secondary task. When comparison and discrimination reports were combined in a single experiment there was a behavioral disassociation: contrast enhanced for comparison responses, but did not change for discrimination judgments, even when participants made both types of judgement for a single stimulus. That a single object can have multiple simultaneous appearances leads inescapably to the conclusion that our unitary mental experience is illusory.
Atheists and agnostics are more reflective than religious believers: Four empirical studies and a meta-analysis
(Public Library of Science, 2016-04-07) Pennycook, Gordon; Ross, Robert M.; Koehler, Derek J.; Fugelsang, Jonathan A.
Individual differences in the mere willingness to think analytically has been shown to predict religious disbelief. Recently, however, it has been argued that analytic thinkers are not actually less religious; rather, the putative association may be a result of religiosity typically being measured after analytic thinking (an order effect). In light of this possibility, we report four studies in which a negative correlation between religious belief and performance on analytic thinking measures is found when religious belief is measured in a separate session. We also performed a meta-analysis on all previously published studies on the topic along with our four new studies (N = 15,078, k = 31), focusing specifically on the association between performance on the Cognitive Reflection Test (the most widely used individual difference measure of analytic thinking) and religious belief. This meta-analysis revealed an overall negative correlation (r) of -.18, 95% Cl [-.21, -.16]. Although this correlation is modest, self-identified atheists (N = 133) scored 18.7% higher than religiously affiliated individuals (N = 597) on a composite measure of analytic thinking administered across our four new studies (d = .72). Our results indicate that the association between analytic thinking and religious disbelief is not caused by a simple order effect. There is good evidence that atheists and agnostics are more reflective than religious believers.
Impact of dissolved oxygen during UV-irradiation on the chemical composition and function of CHO cell culture media
(Public Library of Science, 2016-03-14) Meunier, Sarah M.; Todorovic, Biljana; Dare, Emma V.; Begum, Afroza; Guillemette, Simon; Wenger, Andrew; Saxena, Priyanka; Campbell, J. Larry; Sasges, Michael; Aucoin, Marc G.
Ultraviolet (UV) irradiation is advantageous as a sterilization technique in the biopharmaceutical industry since it is capable of targeting non-enveloped viruses that are typically challenging to destroy, as well as smaller viruses that can be difficult to remove via conventional separation techniques. In this work, we investigated the influence of oxygen in the media during UV irradiation and characterized the effect on chemical composition using NMR and LC-MS, as well as the ability of the irradiated media to support cell culture. Chemically defined Chinese hamster ovary cell growth media was irradiated at high fluences in a continuous-flow UV reactor. UV-irradiation caused the depletion of pyridoxamine, pyridoxine, pyruvate, riboflavin, tryptophan, and tyrosine; and accumulation of acetate, formate, kynurenine, lumichrome, and sarcosine. Pyridoxamine was the only compound to undergo complete degradation within the fluences considered; complete depletion of pyridoxamine was observed at 200 mJ/cm2. Although in both oxygen- and nitrogen-saturated media, the cell culture performance was affected at fluences above 200 mJ/cm2, there was less of an impact on cell culture performance in the nitrogen-saturated media. Based on these results, minimization of oxygen in cell culture media prior to UV treatment is recommended to minimize the negative impact on sensitive media.
Optimizing semantic pointer representations for symbol-like processing in spiking neural networks
(Public Library of Science, 2016-02-22) Gosmann, Jan; Eliasmith, Chris
The Semantic Pointer Architecture (SPA) is a proposal of specifying the computations and architectural elements needed to account for cognitive functions. By means of the Neural Engineering Framework (NEF) this proposal can be realized in a spiking neural network. However, in any such network each SPA transformation will accumulate noise. By increasing the accuracy of common SPA operations, the overall network performance can be increased considerably. As well, the representations in such networks present a trade-off between being able to represent all possible values and being only able to represent the most likely values, but with high accuracy. We derive a heuristic to find the near-optimal point in this trade-off. This allows us to improve the accuracy of common SPA operations by up to 25 times. Ultimately, it allows for a reduction of neuron number and a more efficient use of both traditional and neuromorphic hardware, which we demonstrate here.
Kinetic energy cascade in stably stratified open-channel flows
(Cambridge University Press, 2021-08-26) Atoufi, Amir; Scott, K. Andrea; Waite, Michael L.
In this paper, the kinetic energy cascade in stably stratified open-channel flows is investigated. A mathematical framework to incorporate vertical scales into the conventional kinetic energy spectrum and its budget is introduced. This framework defines kinetic energy density in horizontal spectral and vertical scale space. The energy cascade is studied by analysing the evolution of kinetic energy density. It is shown that energetic streamwise scales (𝜆𝑥) become larger with increasing vertical scale. For the strongest stratification, for which the turbulence becomes intermittent, the energetic streamwise scales are suppressed, and energy density resides in 𝜆𝑥 of the size of the domain. It is shown that, in an unstratified case, vertical scales of the size comparable to the height of the logarithmic layer connect viscous regions to the outer layer. By contrast, in stratified cases, such a connection is not observed. Moreover, it is shown that nonlinear transfer for streamwise scales is dominated by in-plane triad interactions and inter-plane transfer is more active in transferring energy density among small vertical scales of the size comparable to the height of viscous sublayer. The vertical scales of size comparable to the height of the viscous sublayer and buffer layer are the most active scales in the viscous term and the production term in the energy density budget, respectively.
Understanding vaccine hesitancy in Canada: Results of a consultation study by the Canadian Immunization Research Network
(Public Library of Science, 2016-06-03) Dube, Eve; Gagnon, Dominique; Ouakki, Manale; Bettinger, Julia A.; Guay, Maryse; Halperin, Scott; Wilson, Kumanan; Graham, Janice; Witteman, Holly O.; MacDonald, Shannon; Fisher, William; Monnais, Laurence; Tran, Dat; Gagneur, Arnaud; Guichon, Juliet; Saini, Vineet; Heffernan, Jane M.; Meyer, Samantha; Driedger, S. Michelle; Greenberg, Joshua; MacDougall, Heather; Canadian Immunization Research Network
"Vaccine hesitancy" is a concept now frequently used in vaccination discourse. The increased popularity of this concept in both academic and public health circles is challenging previously held perspectives that individual vaccination attitudes and behaviours are a simple dichotomy of accept or reject. A consultation study was designed to assess the opinions of experts and health professionals concerning the definition, scope, and cause of vaccine hesitancy in Canada. We sent online surveys to two panels (1- vaccination experts and 2- front-line vaccine providers). Two questionnaires were completed by each panel, with data from the first questionnaire informing the development of questions for the second. Our participants defined vaccine hesitancy as an attitude (doubts, concerns) as well as a behaviour (refusing some / many vaccines, delaying vaccination). Our findings also indicate that both vaccine experts and front-line vaccine providers have the perception that vaccine rates have been declining and consider vaccine hesitancy an important issue to address in Canada. Diffusion of negative information online and lack of knowledge about vaccines were identified as the key causes of vaccine hesitancy by the participants. A common understanding of vaccine hesitancy among researchers, public health experts, policymakers and health care providers will better guide interventions that can more effectively address vaccine hesitancy within Canada.
Knowledge, perceptions and attitudes toward chronic pain and its management: A cross-sectional survey of frontline pharmacists in Ontario, Canada
(Public Library of Science, 2016-06-07) Patel, Tejal; Chang, Feng; Mohammed, Heba Tallah; Raman-Wilms, Lalitha; Jurcic, Jane; Khan, Ayesha; Sproule, Beth
The treatment of chronic pain consumes a significant share of primary care. Community and family health team pharmacists frequently see patients with chronic pain, thus have the opportunity to improve their care. To assess the knowledge, perceptions, and attitudes of Ontario pharmacists, we invited 5,324 Ontario pharmacists, to participate in an online survey we developed using Qualtrics. The 31-question survey gathered demographic information, assessed pharmacists’ knowledge of three chronic pain conditions; chronic lower back pain (CLBP, eight true/false statements); chronic headache disorder (CHD, eight true/false statements) and painful diabetic neuropathy (PDN, seven true/false statements), and their attitudes toward and perceptions of patients with these conditions, and knowledge, attitudes, and perceptions of opioids in pain management. We received 688 responses (12.9%) and 392 pharmacists completed the survey. The mean age of respondents was 48.5 years and 48.5% were male. More than 50% of respondents were in practice for more than 20 years and 58.7% worked 25–40 hours per week. The mean knowledge scores were 4.5/8, 5.5/8, and 5.3/8 for CBLP, CHD, and PDN respectively. While 95% of respondents were aware of the increasing death rates due to opioid use, only half were familiar with the Canadian guideline for safe opioid prescribing for non-cancer use. Responses were compared based on gender, time in practice and location of practice. Pharmacists with more than ten years of experience scored significantly higher than those with less experience. Fewer differences were found in comparisons of gender and location of practice. Safe and effective care of chronic pain patients, particularly with opioids, will require additional pharmacist education.
Rumen and cecum microbiomes in reindeer (Rangifer tarandus tarandus) are changed in response to a licehn diet and may affect enteric methane emissions
(Public Library of Science, 2016-05-09) Salgado-Flores, Alejandro; Hagen, Live H.; Ishaq, Suzanne L.; Zamanzadeh, Mirzaman; Wright, Andre-Denis G.; Pope, Phillip B.; Sundset, Monica A.
Reindeer (Rangifer tarandus tarandus) are large Holarctic herbivores whose heterogeneous diet has led to the development of a unique gastrointestinal microbiota, essential for the digestions of arctic flora, which may include a large proportion of lichens during winter. Lichens are rich in plant secondary metabolites, which may affect members of the gut microbial consortium, such as the methane-producing methanogenic archaea. Little is known about the effect of lichen consumption on the rumen and cecum microbiotas and how this may affect methanogenesis in reindeer. Here, we examined the effects of dietary lichens on the reindeer gut microbiota, especially methanogens. Samples from the rumen and cecum were collected from two groups of reindeer, fed either lichens (Ld: n=4), or a standard pelleted feed (Pd: n=3). Microbial densities (methanogens, bacteria and protozoa) were quantified using quantitative real-time PCR and methanogen and bacterial diversities were determined by 454 pyrosequencing of the 16S rRNA genes. In general, the density of methanogens were not significantly affected (p>0.05) by the intake of lichens. Methanobrevibacter constituted the main archaeal genus (>95% of reads), with Mbr. thaueri CW as the dominant species in both groups of reindeer. Bacteria belonging to the uncharacterized Ruminococcaceae and the genus Prevotella were the dominant phylotypes in the rumen and cecum, in both diets (ranging between 16-38% total sequences). Bacteria belonging to the genus Ruminococcus (3.5% to 0.6%; p=0.001) and uncharacterized phylotypes within the order Bacteroidales (8.4% to 1.3%; p=0.027), were significantly decreased in the ruman of lichen-fed reindeer, but not in the cecum (p=0.2 and p=0.087, respectively). UniFranc-based analyses showed archaeal and bacterial libraries were significantly different between diets, in both the cecum and the rumen (vegan::Adonis: pseudo-F<0.05). Based upon previous literature, we suggest that the altered methanogen and bacterial profiles may account for expected lower methane emissions from lichen-fed reindeer.
The health and well-being of older adults with Dual Sensory Impairment (DSI) in four countries
(Public Library of Science, 2016-05-05) Guthrie, Dawn M.; Declercq, Anja; Finne-Soveri, Harriet; Fries, Brant E.; Hirdes, John P.
Objectives Dual sensory impairment (DSI) is a combination of vision and hearing impairments that represents a unique disability affecting all aspects of a person's life. The rates of DSI are expected to increase due to population aging, yet little i known about DSI among older adults (65+). The prevalence of DSI and client characteristics were examined among two groups, namely, older adults receiving home care services or those residing in a long-term care (LTC) facility in four countries (Canada, US, Finland, Belgium). Methods Existing data, using an interRAI assessment, were analyzed to compare older adults with DSI to all others across demographic characteristics, functional and psychosocial outcomes. Results In home care, the prevalence of DSI across the four countries ranged from 13.4% to 24.6%; in LTC facilities, it ranged from 9.7% to 33.9%. Clients with DSI were more likely to be 85+, have moderate/severe cognitive impairment, impairments in activities of daily living, and have communication difficulties. Among residents of LTC facilities, individuals with DSI were more likely to be 85+ and more likely have a diagnosis of Alzheimer's disease. Having DSI increased the likelihood of depression in both care settings, but after adjusting for other factors, it remained significant only in the home care sample. Conclusions While the prevalence of DSI cross nationally is similar to that of other illnesses such as diabetes, depression, and Alzheimer's disease, we have a limited understanding of its affects among older adults. Raising awareness of this unique disability is imperative to insure that individuals receive the necessary rehabilitation and supportive services to improve their level of independence and quality of life.
Effects of culture and gender on judgments of intent and responsibility
(Public Library of Science, 2016-04-28) Plaks, Jason E.; Fortune, Jennifer L.; Liang, Lindie H.; Robinson, Jeffrey S.
Do different cultures hold different views of intentionality? In four studies, participants read scenarios in which the actor's distal intent (a focus on a broader goal) and proximal intent (a focus on the mechanics of the act) were manipulated. In Studies 1-2, when distal intent was more prominent in the actor's mind, North Americans rated the actor more responsible than did Chinese and South Asian participants. When proximal intent was more prominent, Chinese and South Asian participants, if anything, rated the actor more responsible. In Studies 3-4, when distal intent was more prominent, male Americans rated the actor more responsible than did female Americans. When proximal intent was more prominent, females rated the actor more responsible. The authors discuss these findings in relation to the literatures on moral reasoning and cultural psychology.
Making sure things really add up: Ways to assess research impact responsibly
(Canadian Association of Research Administrators, 2024-05-13) Bredahl, Laura Megan; Milligan, Ian; Chambers, Thane; Conte, Erica
University administrators love the numbers. The idea of having data to measure, compare, support decision making, and to understand initiatives and invested resources is something we strive for. The idea of using bibliometric data to assess research and benchmark institutional success/lack of success has been a long-standing modus operandi in academic institutions. However, when this type of analysis is done, it often feels like it’s missing something. The data doesn’t always appear to accurately reflect what we know is happening at our institutions, and the impacts that are observed both in our communities and across research disciplines. In this interactive session, we will explore how responsible ways of measuring research, that include quantitative and qualitative assessments and choosing the right indicators, can provide more meaningful data. Through this and thoughtful reflection on the challenges of measuring impacts at large institutions we can more fully reveal the stories of the research being done at our institutions. The session organizers include librarians and research offices, representing the collaborative approach we believe is necessary for institutions to meet these challenges. We will discuss initiatives at Canadian institutions that advocate for the responsible use of research impact metrics. And with the audience, we will explore ways in which these types of assessments can be used at other institutions to change what and how things are measured around research so that more accurate, more holistic, and more meaningful data can be gathered.
Building Momentum in Open Science through Persistent Identifiers: The Final Outcomes of the ORCID Implementation Pilot at the University of Waterloo
(Canadian Research Knowledge Network (CRKN) Online Conference 2026, 2026-05-13) Bredahl, Laura; Ochana, Mary
Persistent identifiers (PIDs) are foundational to advancing open scholarship, improving research visibility, and enabling interoperability across systems. In 2024, the University of Waterloo launched an ORCID Implementation Pilot to strengthen researcher identity management and streamline workflows for researchers and staff. This initiative began as a collaboration between the Library, Office of Research, and Graduate Studies and Postdoctoral Affairs (GSPA), aligning institutional priorities with national and international momentum for PID adoption. Our presentation will share the story of this pilot as a momentum-building collaboration. We will outline the project’s objectives, including integrating ORCID into institutional systems, supporting researchers in creating and maintaining ORCID, and leveraging ORCID to reduce redundancy and improve the consistency and reuse of researcher information. Key highlights will include our success metrics, lessons learned from user engagement, technical and organizational challenges, and strategies we developed for fostering buy-in as we strive toward ORCID becoming embedded in everyday academic and administrative processes.   We will demonstrate how a single pilot can contribute to collective progress toward a sustainable, interoperable research ecosystem. We will discuss future directions and how emerging faculty partnerships serve as proof-of-concept for how ORCID enabled reporting can scale as ORCID has the potential to reshape how researcher information is collected, maintained, and reused across the whole institution. Attendees will gain practical insights into planning and executing ORCID adoption initiatives, as well as how leveraging cross-institutional collaboration can support project success. This session aligns with the conference theme of Creative Collaborations, Collective Momentum by showcasing how partnerships within and beyond an institution can drive meaningful change in research infrastructure and open science practices.
Position Paper: Measuring Research Outputs with Bibliometrics, 2026 Update
(University of Waterloo, 2026) Bredahl, Laura; Carson, Jana; Chan, Wai Yin Winnie; Collins, Nancy; De Gomez, Wendy; Feltracco, Annamaria; Ferrer, Ana; Hale, Jordan; Hirst, Jenny; Kariyapperuma, Kumudinie; Marques, Antonio; Milligan, Ian; Muszycka-Jones, Martha; Santi, Selena M.; Stirling, Peter; Walgate, Jon; University of Waterloo Working Group of Bibliometrics
This current Position Paper is an update from 2016. The inaugural paper provided a high-level review of issues relevant to understanding bibliometrics, and practical recommendations for how to appropriately use these measures. Since first publishing the original paper, there have been consistent questions about; how to better serve the Arts, Humanities and Social Sciences in bibliometrics and research impact, the role of alternative metrics in analyses, the intersection of equity, diversity and inclusion and bibliometrics, collaboration and interdisciplinarity, and practical guidance on the responsible use of metrics. There was also interest in looking at the impact that COVID has had on research and related outcomes. This update incorporates reflections, lessons learned and the modern context into its existing form.
Conceptualizing How to Design for AI Literacy through Game Artifacts
(Association for Computing Machinery New York, NY, United States, 2026-06-13) Tu, Joseph; Smith, Geneva M.; Bassanelli, Simone; Marconi, Annapaola; Nacke, Lennart E.
AI literacy is an emerging research area that increasingly incorporates new forms of computational intelligence, creating opportunities to enrich human learning and interactive experiences. Our scoping review examines design interventions and discourses within AI literacy and games to identify and characterize the learning experiences that prior research has sought to support. Drawing from 45 papers, we identified and analyzed 48 unique design artifacts, including game‑based learning prototypes and gamified systems. We constructed a comprehensive matrix charting each artifact's game or gamification approach, platform, AI literacy focus, game design elements, player requirements, modality, and open‑source availability, providing a detailed view of how AI literacy is represented across these systems. Building on this matrix, we identify nine design suggestions that illustrate how specific design choices shape learners' knowledge, skills, and experiences with AI. Our work clarifies game‑based AI literacy interventions and offers actionable suggestions for designing future systems that effectively leverage games and gamification to support AI learning.
Does reactance against cigarette warning labels matter? Warning label responses and downstream smoking cessation amongst adult smokers in Australia, Canada, Mexico and the United States
(Public Library of Science, 2016-07-13) Cho, Yoo Jin; Thrasher, James F.; Swayampakala, Kamala; Yong, Hua-Hie; McKeever, Robert; Hammond, David; Anshari, Dien; Cummings, K. Michael; Borland, Ron
Objective Some researchers have raised concerns that pictorial health warning labels (HWLs) on cigarette packages may lead to message rejection and reduced effectiveness of HWL messages. This study aimed to determine how state reactance (i.e., negative affect due to perceived manipulation) in response to both pictorial and text-only HWLs is associated with other types of HWL responses and with subsequent cessation attempts. Methods Survey data were collected every 4 months between September 2013 and 2014 from online panels of adult smokers in Australia, Canada, Mexico, and the US were analyzed. Participants with at least one wave of follow-up were included in the analysis (n = 4,072 smokers; 7,459 observations). Surveys assessed psychological and behavioral responses to HWLs (i.e., attention to HWLs, cognitive elaboration of risks due to HWLs, avoiding HWLs, and forgoing cigarettes because of HWLs) and cessation attempts. Participants then viewed specific HWLs from their countries and were queried about affective state reactance. Logistic and linear Generalized Estimating Equation (GEE) models regressed each of the psychological and behavioral HWL responses on reactance, while controlling for socio-demographic and smoking-related variables. Logistic GEE models also regressed having attempted to quit by the subsequent survey on reactance, each of the psychological and behavioral HWL responses (analyzed separately), adjustment variables. Data from all countries were initially pooled, with interactions between country and reactance assessed; when interactions were statistically significant, country-stratified models were estimated. Results Interactions between country and reactance were found in all models that regressed psychological and behavioral HWL responses on study variables. In the US, stronger reactance was associated with more frequent reading of HWLs and thinking about health risks. Smokers from all four countries with stronger reactance reported greater likelihood of avoiding warnings and forgoing cigarettes due to warnings, although the association appeared stronger in the US. Both stronger HWLs responses and reactance were positively associated with subsequent cessation attempts, with no significant interaction between country and reactance. Conclusions Reactance towards HWLs does not appear to interfere with quitting, which is consistent with its being an indicator of concern, not a systematic effort to avoid HWL message engagement.
Impact of soil salinity on the structure of the bacterial endophytic community identified from the roots of caliph medic (Medicago truncatula)
(Public Library of Science, 2016-07-08) Yaish, Mahmoud W.; Al-Lawati, Abbas; Jana, Gerry Aplang; Patankar, Himanshu Vishwas; Glick, Bernard R.
In addition to being a forage crop, Caliph medic (Medicago truncatula) is also a model legume plant and is used for research focusing on the molecular characterization of the interaction between rhizobia and plants. However, the endophytic microbiome in this plant is poorly defined. Endophytic bacteria play a role in supplying plants with the basic requirements necessary for growth and development. Moreover, these bacteria also play a role in the mechanism of salinity stress adaptation in plants. As a prelude to the isolation and utilization of these bacteria in Caliph medic farming, 41 bacterial OTUs were identified in this project from within the interior of the roots of this plant by pyrosequencing of the small ribosomal subunit gene (16S rDNA) using a cultivation-independent approach. In addition, the differential abundance of these bacteria was studied following exposure of the plants to salinity stress. About 29,064 high-quality reads were obtained from the sequencing of six libraries prepared from control and salinity-treated tissues. Statistical analysis revealed that the abundance of ~70% of the OTUs was significantly (p ≤ 0.05) altered in roots that were exposed to salinity stress. Sequence analysis showed a similarity between some of the identified species and other, known, growth-promoting bacteria, marine and salt-stressed soil-borne bacteria, and nitrogen-fixing bacterial isolates. Determination of the amendments to the bacterial community due to salinity stress in Caliph medic provides a crucial step toward developing an understanding of the association of these endophytes, under salt stress conditions, in this model plant. To provide direct evidence regarding their growth promoting activity, a group of endophytic bacteria were isolated from inside of plant roots using a cultivation-dependent approach. Several of these isolates were able to produce ACC-deaminase, ammonia and IAA; and to solubilize Zn+2 and PO4-3. This data is consistent with the predicted occurrence (based on cultivation-independent techniques) of these bacteria and provides some insight into the importance of the endophytic bacteria in Caliph medic when grown under normal and saline conditions.

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