2,688 results on '"Shedden, A."'
Search Results
2. Runtime Resolution of Feature Interactions through Adaptive Requirement Weakening
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Chu, Simon, Shedden, Emma, Zhang, Changjian, Meira-Góes, Rômulo, Moreno, Gabriel A., Garlan, David, and Kang, Eunsuk
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Computer Science - Software Engineering ,Computer Science - Formal Languages and Automata Theory ,Computer Science - Logic in Computer Science ,Electrical Engineering and Systems Science - Systems and Control - Abstract
The feature interaction problem occurs when two or more independently developed components interact with each other in unanticipated ways, resulting in undesirable system behaviors. Feature interaction problems remain a challenge for emerging domains in cyber-physical systems (CPS), such as the Internet of Things and autonomous drones. Existing techniques for resolving feature interactions take a "winner-takes-all" approach, where one out of the conflicting features is selected as the most desirable one, and the rest are disabled. However, when multiple of the conflicting features fulfill important system requirements, being forced to select one of them can result in an undesirable system outcome. In this paper, we propose a new resolution approach that allows all of the conflicting features to continue to partially fulfill their requirements during the resolution process. In particular, our approach leverages the idea of adaptive requirement weakening, which involves one or more features temporarily weakening their level of performance in order to co-exist with the other features in a consistent manner. Given feature requirements specified in Signal Temporal Logic (STL), we propose an automated method and a runtime architecture for automatically weakening the requirements to resolve a conflict. We demonstrate our approach through case studies on feature interactions in autonomous drones., Comment: 10 pages, submitted to SEAMS conference
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- 2023
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3. Sex-specific dementia risk in known or suspected obstructive sleep apnea: a 10-year longitudinal population-based study.
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Braley, Tiffany, Lyu, Xiru, Dunietz, Galit, Schulz, Paul, Bove, Riley, Chervin, Ronald, Paulson, Henry, and Shedden, Kerby
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OSA ,cognitive function ,dementia ,neurodegenerative disorders ,neurological disorders ,women’s health - Abstract
STUDY OBJECTIVES: To evaluate sex-specific associations between known or suspected obstructive sleep apnea (OSA) and dementia risk over 10 years among older women and men. METHODS: This study included 18 815 women and men age 50+ years (dementia-free at baseline) who participated in the Health and Retirement Study (HRS), a nationally representative cohort of US adults. Presence of OSA was defined by self-reported diagnosis or key HRS items that correspond to elements of a validated OSA screening tool (STOP-Bang). Incident dementia cases were identified using a validated, HRS-based algorithm derived from objective cognitive assessments. Survey-weighted regression models based on pseudo-values were utilized to estimate sex- and age-specific differences in cumulative incidence of dementia by OSA status. RESULTS: Data from 18 815 adults were analyzed, of which 9% of women and 8% of men (weighted proportions) met criteria for incident dementia. Known/suspected OSA was more prevalent in men than in women (weighted proportions 68% vs. 31%). Unadjusted sex-stratified analyses showed that known/suspected OSA was associated with higher cumulative incidence of dementia across ages 60-84 years for women and men. By age 80, relative to adults without known/suspected OSA, the cumulative incidence of dementia was 4.7% higher (CI 2.8%, 6.7%) for women with known/suspected OSA, and 2.5% (CI 0.5%, 4.5%) for men with known/suspected OSA, respectively. Adjusted associations between age-specific OSA and cumulative incidence of dementia attenuated for both women and men but remained statistically significant. CONCLUSIONS: OSA contributes to dementia risk in older adults, particularly women. This study illuminates the impact of a potentially modifiable yet frequently overlooked risk factor for dementia onset.
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- 2024
4. Correction: Aberrant BCAT1 expression augments MTOR activity and accelerates disease progression in chronic lymphocytic leukemia
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Shao, Qiangqiang, Wykretowicz, Jedrzej, Hu, Nan, Bedi, Karan, Rizk, Mohamed, Malek, Isabella A., Kumar, Surinder, Lombard, David B., Shedden, Kerby, Scott, David, and Malek, Sami N.
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- 2025
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5. Trends in Mental Health Outcomes of College Students Amid the Pandemic (Roadmap mHealth App): Longitudinal Observational Study
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Gautham Jayaraj, Xiao Cao, Adam Horwitz, Michelle Rozwadowski, Skyla Shea, Shira N Hanauer, David A Hanauer, Muneesh Tewari, Kerby Shedden, and Sung Won Choi
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Computer applications to medicine. Medical informatics ,R858-859.7 ,Public aspects of medicine ,RA1-1270 - Abstract
BackgroundThe mental health crisis among college students intensified amid the COVID-19 pandemic, suggesting an urgent need for innovative solutions to support them. Previous efforts to address mental health concerns have been constrained, often due to the underuse or shortage of services. Mobile health (mHealth) technology holds significant potential for providing resilience-building support and enhancing access to mental health care. ObjectiveThis study aimed to examine the trends in mental health and well-being outcomes over 3 years among college students, with an exploratory aim to assess the potential impact of the Roadmap mHealth app on these outcomes. MethodsA fully automated longitudinal observational study was conducted remotely from a large public academic institution in the Midwestern United States, evaluating mental health and well-being outcomes among college students using the Roadmap mHealth app over 3 fall semesters from 2020 to 2022. The study enrolled 2164 college students in Year I, with 1128 and 1033 students returning in Years II and III, respectively. Participants completed various self-reported measures, including the Patient Health Questionnaire-9 for depression, Generalized Anxiety Disorder-7 for anxiety, and additional metrics for coping, flourishing, and loneliness. ResultsThe findings indicated an evolving trajectory in students’ mental health. In Year I, depression and anxiety levels were higher compared with levels reported between 2014 and 2019, remaining stable into Year II. However, significant decreases were noted by Year III for both depression (Year I mean 7.78, SD 5.65 vs Year III mean 6.21, SD 4.68; t108=–2.90; P=.01) and anxiety (Year I mean 6.61, SD 4.91 vs Year III mean 5.62, SD 4.58; t116=–2.02; P=.046). Problem-focused coping decreased initially from Year I (mean 2.46, SD 0.58) to Year II (mean 2.36, SD 0.60; t1073=–5.87; P
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- 2025
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6. Correlates of multidimensional sleep in premenopausal women: The BioCycle study
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Xinrui Wu, Galit Levi Dunietz, Kerby Shedden, Ronald D. Chervin, Erica C. Jansen, Xiru Lyu, Louise M. O'Brien, Ana Baylin, Jean Wactawski-Wende, Enrique F. Schisterman, and Sunni L. Mumford
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Sleep ,Sleep health ,Sleep variability ,Insomnia ,Bedtime ,Women's health ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Purpose: To identify sleep dimensions (characteristics) that co-occur in premenopausal women. The second aim was to examine associations between multiple dimensions of sleep and a set of demographic, lifestyle, and health correlates. The overarching goal was to uncover patterns of poor-sleep correlates that might inform interventions to improve sleep health of women in this age group. Methods: The BioCycle Study included 259 healthy women aged 18–44y recruited between 2005 and 2007 from Western New York. Participants reported sleep data through daily diaries and questionnaires that were used to create five sleep health dimensions (duration, variability, timing, latency, and continuity). We used multivariate analysis – canonical correlation methods – to identify links among dimensions of sleep health and patterns of demographic, psychological, and occupational correlates. Results: Two distinct combinations of sleep dimensions were identified. The first - primarily determined by low variability in nightly sleep duration, low variability in bedtime (timing), greater nocturnal awakening, and less sleep onset latency – was distinguished from the second – primarily determined by sleep duration.The first combination of sleep dimensions was associated with older age and higher parity, fewer depressive symptoms, and higher stress level. The second combination of sleep dimensions was associated with perception of longer sleep duration as optimal, lower parity, not engaging in shift work, older age, lower stress level, higher prevalence of depressive symptoms, and White race. Conclusion: Among premenopausal women, we demonstrated distinct patterns of sleep dimensions that co-occur and vary by demographic, health, and lifestyle correlates. These findings shed light on the correlates of sleep health vulnerabilities among young women.
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- 2024
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7. Results of selective decontamination with oral neomycin and metronidazole for major colorectal surgery in Australia: A cohort study
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James Wei Tatt Toh, Devansh Shah, Henry Wang, Charlotte Kwik, Joseph Do Woong Choi, Chelsie Leonie Beinke, Paul Morris, Eleni Baird-Gunning, Geoffrey Peter Collins, Fiona Gavegan, Karen Shedden, Toufic El-Khoury, Nimalan Pathma-Nathan, and Kerry Hitos
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Neomycin ,Metronidazole ,Colorectal surgery ,Anastomotic leakage ,Surgical site infection ,Surgery ,RD1-811 - Abstract
Objective: The role of selective decontamination with oral antibiotics (OABs) and mechanical bowel preparation (MBP) prior to elective colorectal surgery is still widely debated. The objective of this study was to compare the outcomes of selective decontamination with neomycin, metronidazole and MBP compared to those of decontamination with MBP alone or with no preparation. Methods: Selective decontamination with neomycin and metronidazole combined with bowel preparation was introduced prior to elective colorectal surgery as part of an enhanced recovery after surgery program at Westmead Hospital, a major Australian tertiary referral hospital, between June 2017 and January 2023. Comparisons between short-term outcomes of OAB + MBP and MBP/no preparation were made using prospectively collected data on length of stay (LOS), readmission, mortality within 30 days, anastomotic leakage (AL), surgical site infection (SSI), urinary tract infection, deep venous thrombosis and/or pulmonary embolism, pneumonia, and ileus. Follow-up was limited to hospital stays and subsequent presentations within the health district within thirty days of surgery. The Mann–Whitney U test was used to analyse continuous data, and the chi-square test was used for categorical data. Univariate and multivariate regression modelling was performed to identify risk factors associated with an increased likelihood of SSI and AL. Results: Patients with oral neomycin and metronidazole combined with bowel preparation had reduced superficial SSI (2.7% vs. 7.6%, p = 0.043) and overall complications (32.7% vs. 44.6%, p = 0.020), particularly Clavien–Dindo 1 complications (7.3% vs. 16.5%, p = 0.009). However, the differences in AL (2.7% vs. 4.5%, p = 0.369) and organ/space SSI (1.3% vs. 3.7%, p = 0.327) were not statistically significant. The median LOS (6 d vs. 6 d, p = 0.370) was not different between the groups. Conclusion: Selective decontamination with neomycin and metronidazole reduces the risk of SSIs and overall complications. There was a trend to toward a lower AL, but this difference was not statistically significant.
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- 2024
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8. Causal Relationships and Programming Outcomes: A Transcranial Magnetic Stimulation Experiment.
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Hammad Ahmad, Madeline Endres, Kaia Newman, Priscila Santiesteban, Emma Shedden, and Westley Weimer
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- 2024
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9. Toward a Measure of Collective Digital Capacity: An Exploratory Analysis.
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Tawanna R. Dillahunt, Kerby Shedden, Mila Ekaterina Filipof, Soyoung Lee, Mustafa Naseem, Kentaro Toyama, and Julie Hui
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- 2024
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10. The overlooked burden of persistent physical symptoms: a call for action in European healthcare
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Blanch, Jordi, Bogaerts, Katleen, Boye, Birgitte, Burton, Chris, Cosci, Fiammetta, Engelmann, Petra, Fink, Per, Fischer, Susanne, Frisch, Stephan, Frostholm, Lisbeth, Gormsen, Lise Kirstine, Greco, Monica, Kallesoe, Karen Hansen, Hartman, Tim olde, Hechler, Tanja, Hennemann, Severin, Henningsen, Peter, Hüfner, Katharina, Hüsing, Paul, Ronel, Joram, von Känel, Roland, Kenedi, Christopher A., Köteles, Ferenc, Kohlmann, Sebastian, Kop, Willem J., Lehnen, Nadine, Levenson, James, Löwe, Bernd, Maehder, Kerstin, Martin, Alexandra, Pieh, Christoph, Pitron, Victor, Rask, Charlotte Ulrikka, Rief, Winfried, Rosendal, Marianne, Rosmalen, Judith, Rymaszewska, Joanna, Sainio, Markku, Salzmann, Stefan, Schaefert, Rainer, Selinheimo, Sanna, Shedden-Mora, Meike, Stone, Jon, Tak, Lineke, Toussaint, Anne, Uhlenbusch, Natalie, Van den Bergh, Omer, de Vroege, Lars, Weigel, Angelika, Werneke, Ursula, and Witthöft, Michael
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- 2025
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11. Do trap-neuter-return (TNR) practices contribute to human–coyote conflicts in southern California?
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Bucklin, Danielle M., Shedden, Jennifer M., Quinn, Niamh M., Cummings, Robert, and Stapp, Paul
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- 2023
12. Psychological factors associated with Long COVID: a systematic review and meta-analysisResearch in context
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Petra Engelmann, Max Reinke, Clara Stein, Stefan Salzmann, Bernd Löwe, Anne Toussaint, and Meike Shedden-Mora
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Long COVID ,Post COVID-19 condition ,Persistent somatic symptoms ,Biopsychosocial model ,Psychological factors ,Medicine (General) ,R5-920 - Abstract
Summary: Background: Despite the immense impact of Long COVID on public health and those affected, its aetiology remains poorly understood. Findings suggest that psychological factors such as depression contribute to symptom persistence alongside pathophysiological mechanisms, but knowledge of their relative importance is limited. This study aimed to synthesise the current evidence on psychological factors potentially associated with Long COVID and condition-relevant outcomes like quality of life. Methods: In this systematic review and meta-analysis, MEDLINE, PsycINFO, and the Cochrane Database of Systematic Reviews were searched for peer-reviewed studies published in English from 2019 to January 2, 2024. Studies providing cross-sectional or longitudinal data on the association between at least one psychological variable and the presence of Long COVID (primary outcome) or condition-relevant secondary outcomes (symptom severity, impairment, quality of life, and healthcare utilisation) were included. Psychological constructs with at least five comparisons were pooled as odds ratio (OR) for categorical data and standardised mean difference (SMD) for continuous data in random-effects meta-analyses of cross-sectional studies with control groups. This review is registered with PROSPERO, CRD42023408320. Findings: 113 studies (n = 312,831 patients with Long COVID) provided data on at least one psychological variable, 63 in cross-sectional group comparisons, 53 in cross-sectional associations, and 18 longitudinal. Most reported findings related to depression and anxiety, and — less frequently — to physical activity, posttraumatic stress disorder, stress, and history of mental illness. Depression (OR 2.35; 95% CI, 1.49–3.70) and anxiety (OR 2.53; 95% CI, 1.76–3.61) were significantly associated with Long COVID and higher in affected patients than controls (depression: SMD 0.88; 95% CI, 0.66–1.11; anxiety: SMD 0.74; 95% CI, 0.50–0.99), while results for physical activity and stress were non-significant. In most prospective studies, the investigated psychological constructs significantly predicted Long COVID. Interpretation: Evidence suggests depression and anxiety to be co-occurring phenomena and predictive factors of Long COVID. Future studies should prospectively investigate psychological constructs such as emotion regulation or dysfunctional symptom expectations, which are well-known risk factors and therapeutic targets of persistent somatic symptoms in other medical conditions, but are so far understudied in Long COVID. Funding: None.
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- 2024
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13. Psychological risk factors of somatic symptom disorder: A systematic review and meta-analysis of cross-sectional and longitudinal studies
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Smakowski, Abigail, Hüsing, Paul, Völcker, Sophia, Löwe, Bernd, Rosmalen, Judith G.M., Shedden-Mora, Meike, and Toussaint, Anne
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- 2024
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14. Can side effect expectations be assessed implicitly? A comparison of explicit and implicit expectations of vaccination side effects
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Borgmann, Anna, Petrie, Keith J., Seewald, Anna, and Shedden-Mora, Meike
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- 2024
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15. Is preoperative hypoalbuminemia or hypoproteinemia a reliable marker for anastomotic leakage risk in patients undergoing elective colorectal surgery in an enhanced recovery after surgery (ERAS) program?
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Do Woong Choi, Joseph, Kwik, Charlotte, Vivekanandamoorthy, Nurojan, Shanmugalingam, Aswin, Allan, Lachlan, Gavegan, Fiona, Shedden, Karen, Peters, Ashleigh, Khoury, Toufic El, Pathmanathan, Nimalan, and Toh, James Wei Tatt
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- 2023
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16. Logs or Self-Reports? Misalignment Between Behavioral Trace Data and Surveys When Modeling Learner Achievement Goal Orientation.
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Heeryung Choi, Philip H. Winne, Christopher Brooks 0001, Warren Li, and Kerby Shedden
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- 2023
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17. Response to Commentary: The framework for systematic reviews on psychological risk factors for persistent somatic symptoms and related syndromes and disorders (PSY-PSS)
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Paul Hüsing, Abigail Smakowski, Bernd Löwe, Maria Kleinstäuber, Anne Toussaint, and Meike C. Shedden-Mora
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somatic symptom and related disorders ,systematic reviews ,somatoform disorders ,bodily distress disorder ,psychological factors ,persistent somatic symptoms ,Psychiatry ,RC435-571 - Published
- 2024
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18. Modeling periodicity in equid serial enamel isotopes as a proxy for precipitation seasonality
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Norwood, Alexandra L., Pobiner, Briana L., Shedden, Kerby, and Kingston, John D.
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- 2023
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19. Testing Landmark-Specific Effects on Route Navigation in an Ecologically Valid Setting: A Simulated Driving Study
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Jabbari, Yasaman, Kenney, Darren M., von Mohrenschildt, Martin, and Shedden, Judith M.
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We used a driving simulator to investigate landmark-based route navigation in young adults. Previous research has examined how proximal and distal landmarks influence route navigation, however, these effects have not been extensively tested in ecologically-relevant settings. We used a virtual town in which participants learned various routes while simultaneously driving. We first examined the effect of four different landmark conditions on navigation performance, such that each driver experienced one of four versions of the town with either proximal landmarks only, distal landmarks only, both proximal and distal landmarks, or no landmarks. Drivers were given real-time navigation directions along a route to a target destination, and were then tested on their ability to navigate to the same destination without directions. We found that the presence of proximal landmarks significantly improved route navigation. We then examined the effect of prior exposure to proximal vs. distal landmarks by testing the same drivers in the same environment they previously encountered, but with the landmarks removed. In this case, we found that prior exposure to distal landmarks significantly improved route navigation. The present results are in line with existing research on route navigation and landmarks, suggesting that these findings can be extended to ecologically-relevant settings.
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- 2022
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20. Stimulus Onset Asynchrony Affects Weighting-related Event-related Spectral Power in Self-motion Perception.
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Ben Townsend, Joey K. Legere, Martin v. Mohrenschildt, and Judith M. Shedden
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- 2023
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21. "It's teaching Jim, but not as we know it" : an examination of the beliefs and attitudes of teachers to the use of technology in Further & Vocational Education from a teacher's perspective
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Shedden, Robert John
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371.33 - Abstract
This study sought to understand the beliefs and attitudes of teachers in Further and Vocational Education regarding the use and usefulness of technology in their teaching practice. Policymakers and advocates view increased access to, but continued under-utilisation of technology as indicative of how the sector is failing to meet the expectations and demands from industry. This study examined the underlying perceptions of teachers and identified the barriers and enablers that presented themselves to technology integration. I wanted to gain an understanding in what ways and how often teachers were using technology in their teaching practices. Additionally, teacher's perceptions about the potential contribution that technology could make to their teaching practice would be explored. The study was completed in three phases; the first was an online questionnaire distributed through the college intranet networks and yielded 229 responses. The second phase was another online questionnaire; and this one was distributed directly to teachers that had confirmed that they would be prepared to continue with the study and was sent to 31 teacher’s work email addresses resulting in 21 completed surveys. Eleven one-to-one interviews completed the third phase of the study. The interviews used photo-elicitation to examine the beliefs of the teachers from the Further Education (FE) colleges across a range of subject areas. Each phase of the research was designed to elicit information relating to teacher’s perceptions of the utility and value of technology in their teaching. The results presented in this thesis reflect many of the findings from previous research from other education sectors, namely schools and universities; however other perceptions reflected the uniqueness of the Further and Vocational Education sector and are perhaps a reflection of the demographics of the sector. The main findings of the study were that several barriers existed to the integration and use of technology, a perceived lack of time along with lack of training and support in how to teach effectively using technology. Insufficient provision and access to technology within colleges meant that there was a reliance on students using personal devices to supplement lack of provision in the college, raising issues in low socioeconomic areas. Additionally, there was a perception that technology integration had been superseded in recent years by other CPD mandated for external audits and inspection.
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- 2020
22. Evaluating the ecological hypothesis: early life salivary microbiome assembly predicts dental caries in a longitudinal case-control study
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Freida Blostein, Deesha Bhaumik, Elyse Davis, Elizabeth Salzman, Kerby Shedden, Melissa Duhaime, Kelly M. Bakulski, Daniel W. McNeil, Mary L. Marazita, and Betsy Foxman
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Oral microbiome ,Early childhood ,Ecological hypothesis ,Early childhood caries ,16S rRNA gene ,Whole genome shotgun metagenomics ,Microbial ecology ,QR100-130 - Abstract
Abstract Background Early childhood caries (ECC)—dental caries (cavities) occurring in primary teeth up to age 6 years—is a prevalent childhood oral disease with a microbial etiology. Streptococcus mutans was previously considered a primary cause, but recent research promotes the ecologic hypothesis, in which a dysbiosis in the oral microbial community leads to caries. In this incident, density sampled case-control study of 189 children followed from 2 months to 5 years, we use the salivary bacteriome to (1) prospectively test the ecological hypothesis of ECC in salivary bacteriome communities and (2) identify co-occurring salivary bacterial communities predicting future ECC. Results Supervised classification of future ECC case status using salivary samples from age 12 months using bacteriome-wide data (AUC-ROC 0.78 95% CI (0.71–0.85)) predicts future ECC status before S. mutans can be detected. Dirichlet multinomial community state typing and co-occurrence network analysis identified similar robust and replicable groups of co-occurring taxa. Mean relative abundance of a Haemophilus parainfluenzae/Neisseria/Fusobacterium periodonticum group was lower in future ECC cases (0.14) than controls (0.23, P value < 0.001) in pre-incident visits, positively correlated with saliva pH (Pearson rho = 0.33, P value < 0.001) and reduced in individuals who had acquired S. mutans by the next study visit (0.13) versus those who did not (0.20, P value < 0.01). In a subset of whole genome shotgun sequenced samples (n = 30), case plaque had higher abundances of antibiotic production and resistance gene orthologs, including a major facilitator superfamily multidrug resistance transporter (MFS DHA2 family P BH value = 1.9 × 10−28), lantibiotic transport system permease protein (P BH value = 6.0 × 10−6) and bacitracin synthase I (P BH value = 5.6 × 10−6). The oxidative phosphorylation KEGG pathway was enriched in case plaque (P BH value = 1.2 × 10−8), while the ABC transporter pathway was depleted (P BH value = 3.6 × 10−3). Conclusions Early-life bacterial interactions predisposed children to ECC, supporting a time-dependent interpretation of the ecological hypothesis. Bacterial communities which assemble before 12 months of age can promote or inhibit an ecological succession to S. mutans dominance and cariogenesis. Intragenera competitions and intergenera cooperation between oral taxa may shape the emergence of these communities, providing points for preventive interventions. Video Abstract
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- 2022
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23. Parasitism in heterogeneous landscapes: Association between conserved habitats and gastrointestinal parasites in populations of wild mammals.
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Solórzano-García, Brenda, White, Jennifer M., and Shedden, Aralisa
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- 2023
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24. Tensor models for linguistics pitch curve data of native speakers of Afrikaans
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Hornstein, Michael, Zhou, Shuheng, and Shedden, Kerby
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Statistics - Methodology - Abstract
We use tensor analysis techniques for high-dimensional data to gain insight into pitch curves, which play an important role in linguistics research. In particular, we propose that demeaned phonetics pitch curve data can be modeled as having a Kronecker product inverse covariance structure with sparse factors corresponding to words and time. Using data from a study of native Afrikaans speakers, we show that by targeting conditional independence through a graphical model, we reveal relationships associated with natural properties of words as studied by linguists. We find that words with long vowels cluster based on whether the vowel is pronounced at the front or back of the mouth, and words with short vowels have strong edges associated with the initial consonant., Comment: 20 pages, 7 figures, 1 table in main paper; 51 pages, 48 figures, 2 tables in Appendix
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- 2018
25. Are TNR Practices Contributing to Human-Coyote Conflicts in Southern California?
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Bucklin, Danielle M., Shedden, Jennifer M., Quinn, Niamh M., Cummings, Robert, and Stapp, Paul
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Canis latrans ,free-roaming cats ,human-wildlife conflict ,southern California ,TNR ,trap-neuter-release ,urban coyotes ,wildlife feeding - Abstract
Coyotes are among the most successful carnivores in urban and suburban environments, which has increasingly led to conflicts with pets and people in southern California. One possible contributor to high coyote population densities and human-coyote conflicts is an abundance of free-roaming domestic cats subsidized by backyard feeding and trap-neuter-release (TNR) programs. To determine if coyotes regularly eat free-roaming cats, we identified prey items in the stomachs of 311 coyotes between 2015 and 2018; specimens were either road-killed coyotes or coyotes taken as nuisance animals. We used two methods to estimate coyote diet: visual identification of stomach contents and molecular polymerase-chain reaction (PCR) analysis of prey remains in stomachs. A total of 245 coyotes stomachs contained identifiable food items, including 200 (43%) that contained mammalian prey (based on hair, bones, and tissue); 178 of these had sufficient tissue from which DNA could be extracted. Combining the two methods, we found cat remains in 35% (n = 86) of stomachs with identifiable mammalian remains. This makes cats the most common mammalian prey item identified, surpassing rabbits and small rodents, and means cats are likely a more common prey than has been reported previously, including in other areas of southern California. We used a GIS approach to compare landscape characteristics associated with known locations of coyotes that ate cats to the same characteristics around locations determined to be TNR cat colonies based on public shelter records. These characteristics included amount and intensity of urban development, coverage of grassland and shrubland, building density, and the distance to the nearest natural vegetation; these were entered into a principal component analysis (PCA) to create composite variables that described the degree of urbanization around coyote and TNR colony locations. Logistic regression of PCA variables revealed that cat-eating coyotes were significantly associated with landscapes that were more intensively developed, had little natural or altered green space, and a higher building density than coyotes that did not have cats in their stomachs. Locations of TNR cat colonies had similar landscape characteristics, with colonies often located in intensively developed areas such as apartment complexes or industrial or commercial zones that are relatively far from natural areas. The subset of coyotes associated with TNR colonies were also highly likely to have consumed cats. Coyotes that had been removed (vs. roadkill) tended to be cat-eaters, suggesting that consumption of pets may have led to targeting these coyotes for lethal removal. The high frequency of cats in coyote diets, combined with the concordance of landscape characteristics associated with TNR colonies and cat-eating coyotes, support the argument that high cat densities and supplemental feeding attract coyotes. Effective mitigation of human-coyote conflicts in southern California may require a ban on outdoor feeding of cats and wildlife, and the removal of TNR colonies that coyotes apparently exploit as an abundant source of food.
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- 2020
26. Do Coyotes Eat Mesocarnivores in Southern California? A Molecular Genetic Analysis
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Shedden, Jennifer M., Bucklin, Danielle M., Quinn, Niamh M., and Stapp, Paul
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Canis latrans ,coyote ,Didelphis virginiana ,Mephitis mephitis ,mesocarnivores ,molecular genetics ,opossum ,Procyon lotor ,raccoon ,rodenticide ,striped skunk ,urban carnivores - Abstract
Urban coyotes are commonly exposed to rodenticides used to control non-native commensal rodents, but these rodents are rare in published accounts of their diets. An alternative source of rodenticide exposure is through the consumption of mesocarnivores that have themselves eaten either toxic bait directly or poisoned rodents or invertebrates. Carcasses of 311 nuisance and road-killed coyotes from suburban and urban areas of southern California were collected from 2016-2018. Stomachs were dissected and prey items were identified visually. Stomach contents containing tissue from suspected mammalian prey (N = 178) were homogenized and DNA was extracted. Genus-specific primers (123-366 bp) were designed for Virginia opossums, raccoons, and striped skunks, regionally common species that are known to be consumed by coyotes. PCR was performed for each primer pair, and presence of PCR products of particular amplicon lengths were determined by gel electrophoresis. Coyote stomachs containing a PCR product of the appropriate size were considered to contain that prey item. Land use data were used to assess landscape factors that are associated with the consumption of mesocarnivores. Combining both techniques, mesocarnivores were detected at low frequencies: opossums (8%) were more common than raccoons (2%) and skunks (2%). Some 72% of meso-carnivores present in stomachs were detected by molecular methods, while 66% were identified by morphological methods. Opossums were associated with increased development and anthropogenic land use, while skunks were associated with large natural areas, and raccoons used all habitat types. The extent to which mesocarnivores themselves eat poisoned prey remains unknown, although they may be a potential source of exposure for coyotes. Additionally, landscape factors do not appear to be related to raccoon consumption but may influence presence, and therefore consumption, of skunks and opossums.
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- 2020
27. Pre-surgery optimization of patients’ expectations to improve outcome in heart surgery: Study protocol of the randomized controlled multi-center PSY-HEART-II trial
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Salzmann, Stefan, Laferton, Johannes A.C., Shedden-Mora, Meike C., Horn, Nicole, Gärtner, Laura, Schröder, Lara, Rau, Jörn, Schade-Brittinger, Carmen, Murmann, Kirsten, Rastan, Ardawan, Andrási, Térezia B., Böning, Andreas, Salzmann-Djufri, Miriam, Löwe, Bernd, Brickwedel, Jens, Albus, Christian, Wahlers, Thorsten, Hamm, Alfons, Hilker, Lutz, Albert, Wolfgang, Falk, Volkmar, Zimmermann, Tanja, Ismail, Issam, Strauß, Bernhard, Doenst, Torsten, Schedlowski, Manfred, Moosdorf, Rainer, and Rief, Winfried
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- 2022
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28. Baseline depressive symptoms, personal control, and concern moderate the effects of preoperative psychological interventions: the randomized controlled PSY-HEART trial
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Horn, Nicole, Laferton, Johannes A. C., Shedden-Mora, Meike C., Moosdorf, Rainer, Rief, Winfried, and Salzmann, Stefan
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Coronary artery bypass -- Psychological aspects -- Methods ,Depression, Mental -- Risk factors -- Health aspects ,Preoperative care -- Psychological aspects ,Psychology and mental health - Abstract
This study examined whether baseline (3-14 days pre-surgery) levels of (i) depressive or (ii) anxiety symptoms and (iii) illness beliefs moderate the effects of additional preoperative interventions before coronary artery bypass graft surgery on (i) depressive or (ii) anxiety symptoms and (iii) illness beliefs 1 day before surgery, 1 week and 6 months after surgery. In the PSY-HEART trial, 115 patients were assessed. They were randomized into one of three groups: 1. receiving standard medical care only (SMC), additional psychological interventions: 2. aiming to optimize patients' expectations (EXPECT), or 3. focusing on emotional support. Patients with a higher baseline level of depressive symptoms receiving a preoperative psychological intervention indicated lower depressive symptoms 6 months after surgery compared to SMC. EXPECT increased personal control and concern levels in patients with low baseline personal control/concern 1 day before surgery. Brief preoperative psychological interventions can improve psychological outcomes in heart surgery patients. Baseline status may moderate these effects. The study has been approved by the medical ethics committee of the Philipps University of Marburg and has been pre-registered at www.clinicaltrials.gov (NCT01407055) on August 1, 2011., Author(s): Nicole Horn [sup.1] , Johannes A. C. Laferton [sup.2] , Meike C. Shedden-Mora [sup.3] [sup.4] , Rainer Moosdorf [sup.5] , Winfried Rief [sup.1] , Stefan Salzmann [sup.1] Author Affiliations: [...]
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- 2022
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29. Key patient demographics shape innate immune topography in noncritical hypoxic COVID-19 pneumonia
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Allison C. Billi, Rachael Wasikowski, Feiyang Ma, Srilakshmi Yalavarthi, Claire K. Hoy, Yu Zuo, Matthew T. Patrick, Neha Shah, Christine Parker, Chad Aaronson, Alyssa Harbaugh, Matthew F. Lucido, Kerby Shedden, Krishna Rao, Heidi B. IglayReger, Charles F. Burant, J. Michelle Kahlenberg, Lam C. Tsoi, Johann E. Gudjonsson, Jason S. Knight, and Yogendra Kanthi
- Subjects
COVID-19 ,Immunology ,Medicine - Abstract
Risk of severe disease and death due to COVID-19 is increased in certain patient demographic groups, including those of advanced age, male sex, and obese body mass index. Investigations of the biological variations that contribute to this risk have been hampered by heterogeneous severity, with immunologic features of critical disease potentially obscuring differences between risk groups. To examine immune heterogeneity related to demographic risk factors, we enrolled 38 patients hospitalized with clinically homogeneous COVID-19 pneumonia — defined as oxygen saturation less than 94% on room air without respiratory failure, septic shock, or multiple organ dysfunction — and performed single-cell RNA-Seq of leukocytes collected at admission. Examination of individual risk factors identified strong shifts within neutrophil and monocyte/dendritic cell (Mo/DC) compartments, revealing altered immune cell type–specific responses in higher risk COVID-19 patient subgroups. Specifically, we found transcriptional evidence of altered neutrophil maturation in aged versus young patients and enhanced cytokine responses in Mo/DCs of male versus female patients. Such innate immune cell alterations may contribute to outcome differences linked to these risk factors. They also highlight the importance of diverse patient cohorts in studies of therapies targeting the immune response in COVID-19.
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- 2023
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30. Beta-band power is an index of multisensory weighting during self-motion perception
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Townsend, Ben, Legere, Joey K., Mohrenschildt, Martin v., and Shedden, Judith M.
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- 2022
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31. Long-term assessment of the translocation of an endangered primate into an agroforestry system
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M Franquesa-Soler, JF Aristizabal, E Andresen, I Vélez del Burgo, A Shedden-González, and E Rodríguez-Luna
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Zoology ,QL1-991 ,Botany ,QK1-989 - Abstract
Translocation is increasingly being used as a conservation tool in wildlife management, but long-term assessments of the animals’ establishment in the new habitat are rarely done. In addition, finding protected areas for translocations can often be a limitation, but habitat patches managed for productive purposes could potentially be used for translocations. Here, we present a translocation case study of the Endangered Mexican howler monkey Alouatta palliata mexicana into a forest fragment managed as an agroforest in the Los Tuxtlas Biosphere Reserve (Mexico). We compared the behavior of the translocated focal group 6 yr after translocation with that observed 1 yr after translocation (Year 1 vs. Year 6), and with reference parameters for conserved forest. We also examined the 14 yr trajectory of the translocated population through published data. We found that in Year 6, monkeys spent less time on locomotion and more time consuming fruit than in Year 1. The focal group in Year 6 had doubled its activity area compared to Year 1. All behavioral parameters during Year 6 were similar to those reported for the species in conserved forest. During the first 14 yr, the translocated population increased at a rate of 1.29 ind. yr-1. We conclude that this translocation succeeded in establishing a thriving population and that certain agroforestry systems may be adequate habitat for primate translocations. We also discuss how the translocation of howler monkeys into defaunated habitats might help restore ecological functions associated with these primates, such as the dispersal of large-seeded plants. Long-term information on successful primate translocations has high practical value for designing adequate conservation strategies in anthropogenic landscapes.
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- 2022
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32. Patterns of Sleep Duration and Metabolic Biomarkers Across the Menstrual Cycle.
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Dunietz, Galit Levi, Shedden, Kerby, Lyu, Xiru, Chervin, Ronald D, Baylin, Ana, O'Brien, Louise M, Jansen, Erica C, Wactawski-Wende, Jean, Schisterman, Enrique F, and Mumford, Sunni L
- Subjects
SLEEP duration ,SLEEP ,INSULIN resistance ,DIARY (Literary form) ,MENSTRUAL cycle ,LEPTIN - Abstract
Context Along the menstrual cycle, associations between inconsistent sleep duration and levels of metabolic biomarkers are uncertain and could involve fluctuations in estrogen concentrations. Objective To examine associations between patterns of sleep duration and metabolic biomarkers across 2 menstrual cycles within a cohort of premenopausal women. Methods The BioCycle Study was conducted in New York between 2005 and 2007, enrolling 259 premenopausal women over 2 menstrual cycles. This microlongitudinal cohort study involved intensive data collection including daily sleep diaries and biomarker assessments of leptin, insulin, and glucose at 16 key points timed to menstrual cycle phases. We considered dynamic sleep duration as hours slept 1 night or as mean hours slept during the 2 nights before each biomarker assessment. Variability in habitual sleep duration (ie, reported daily sleep duration) was summarized across both menstrual cycles. Variation in habitual sleep duration was computed using L-moments, a robust version of dispersion, skewness, and kurtosis. To examine associations between patterns of sleep duration and metabolic biomarkers, we fitted a series of linear mixed models with random intercepts and inverse probability weighting. These models were adjusted for potential demographic, lifestyle, health confounders, and menstrual cycle phase. Results Sleep duration 1 night or 2 nights before clinic visits were not associated with metabolic biomarker measures. However, overall variability (dispersion) in habitual sleep duration was associated with lower mean insulin Homeostatic Model Assessment for Insulin Resistance levels, but not glucose. Moreover, extremely short or long bouts of sleep duration were associated with higher mean levels of leptin, insulin, and Homeostatic Model Assessment for Insulin Resistance. Conclusion These data suggest that variation in habitual sleep duration along the menstrual cycle may be associated with metabolic function. [ABSTRACT FROM AUTHOR]
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- 2025
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33. Non-separable covariance models for spatio-temporal data, with applications to neural encoding analysis
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Park, Seyoung, Shedden, Kerby, and Zhou, Shuheng
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Statistics - Methodology ,Statistics - Applications - Abstract
Neural encoding studies explore the relationships between measurements of neural activity and measurements of a behavior that is viewed as a response to that activity. The coupling between neural and behavioral measurements is typically imperfect and difficult to measure.To enhance our ability to understand neural encoding relationships, we propose that a behavioral measurement may be decomposable as a sum of two latent components, such that the direct neural influence and prediction is primarily localized to the component which encodes temporal dependence. For this purpose, we propose to use a non-separable Kronecker sum covariance model to characterize the behavioral data as the sum of terms with exclusively trial-wise, and exclusively temporal dependencies. We then utilize a corrected form of Lasso regression in combination with the nodewise regression approach for estimating the conditional independence relationships between and among variables for each component of the behavioral data, where normality is necessarily assumed. We provide the rate of convergence for estimating the precision matrices associated with the temporal as well as spatial components in the Kronecker sum model. We illustrate our methods and theory using simulated data, and data from a neural encoding study of hawkmoth flight; we demonstrate that the neural encoding signal for hawkmoth wing strokes is primarily localized to a latent component with temporal dependence, which is partially obscured by a second component with trial-wise dependencies., Comment: 48 pages, 10 figures
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- 2017
34. Dyadic and Individual Variation in 24-Hour Heart Rates of Cancer Patients and Their Caregivers
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Rajnish Kumar, Junhan Fu, Bengie L. Ortiz, Xiao Cao, Kerby Shedden, and Sung Won Choi
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heart rate (HR) ,cancer ,hematopoietic cell transplantation (HCT) ,dyad ,circadian ,canonical correlation analysis ,Technology ,Biology (General) ,QH301-705.5 - Abstract
Background: Twenty-four-hour heart rate (HR) integrates multiple physiological and psychological systems related to health and well-being, and can be continuously monitored in high temporal resolution over several days with wearable HR monitors. Using HR data from two independent datasets of cancer patients and their caregivers, we aimed to identify dyadic and individual patterns of 24 h HR variation and assess their relationship to demographic, environmental, psychological, and clinical variables of interest. Methods: a novel regularized approach to high-dimensional canonical correlation analysis (CCA) was used to identify factors reflecting dyadic and individual variation in the 24 h (circadian) HR trajectories of 430 people in 215 dyads, then regression analysis was used to relate these patterns to explanatory variables. Results: Four distinct factors of dyadic covariation in circadian HR were found, contributing approximately 7% to overall circadian HR variation. These factors, along with non-dyadic factors reflecting individual variation exhibited diverse and statistically robust patterns of association with explanatory variables of interest. Conclusions: Both dyadic and individual anomalies are present in the 24 h HR patterns of cancer patients and their caregivers. These patterns are largely synchronous, and their presence robustly associates with multiple explanatory variables. One notable finding is that higher mood scores in cancer patients correspond to an earlier HR nadir in the morning and higher HR during the afternoon.
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- 2024
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35. Forest maturity has a stronger influence on the prevalence of spider monkeys than howler monkeys in an anthropogenically impacted rainforest landscape
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Shedden, A., Dunn, J. C., Martínez-Mota, R., Cristóbal-Azkárate, J., Gillingham, P. K., MacSwiney-González, C., Newton, A. C., Rodríguez-Luna, E., and Korstjens, A. H.
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- 2022
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36. The framework for systematic reviews on psychological risk factors for persistent somatic symptoms and related syndromes and disorders (PSY-PSS)
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Paul Hüsing, Abigail Smakowski, Bernd Löwe, Maria Kleinstäuber, Anne Toussaint, and Meike C. Shedden-Mora
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persistent somatic symptoms ,somatic symptom disorder ,bodily distress disorder ,functional somatic syndromes ,psychological risk factors ,Psychiatry ,RC435-571 - Abstract
IntroductionNumerous psychological factors are believed to play a pivotal role in the development and maintenance of persistent somatic symptoms (PSS) in all fields of medicine. However, very few of these factors have been empirically investigated in relation to PSS. The aim of this study is firstly to propose a framework and define search terms for systematic reviews on the empirical evidence and diagnostic value of psychological risk factors for PSS and PSS-related outcomes (PSY-PSS). Secondly, the application of the framework is illustrated using the example of a systematic review on the relevance of psychological factors in somatic symptom disorders (SSD; DSM-5) and bodily distress disorders (BDD; ICD-11).MethodsFollowing a narrative review approach, two comprehensive lists of search terms to identify studies in (1) relevant patient groups with PSS and (2) relevant psychological factors were generated by reviewing the current literature and employing an iterative process of internal revision and external expert feedback.ResultsWe identified 83 relevant symptoms, syndromes and disorders for which we defined a total of 322 search terms (list 1). We further comprised 120 psychological factors into 42 subcategories and 7 main categories (list 2). The introduced lists can be combined to conduct systematic reviews on one or more specific psychological factors in combination with any symptom, syndrome or disorder of interest. A protocol of the application of this framework in a systematic review and meta-analysis on psychological etiological factors of SSD and BDD is presented following the PRISMA guidelines.DiscussionThis framework will help to gather systematic evidence on psychological factors in order to improve the understanding of the etiology of PSS, to refine future diagnostic conceptualizations of PPS, and to develop optimized mechanism-based interventions for individuals with PPS and related syndromes and disorders.
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- 2023
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37. Runtime Resolution of Feature Interactions through Adaptive Requirement Weakening.
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Simon Chu, Emma Shedden, Changjian Zhang, Rômulo Meira-Góes, Gabriel A. Moreno, David Garlan, and Eunsuk Kang
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- 2023
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38. The Role of Deception in Securing Our Cyberspace
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Mphago, Banyatsang, primary, Mpoeleng, Dimane, additional, and Masupe, Shedden, additional
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- 2022
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39. Symptom perception in chronic kidney disease - an expert survey among nephrologists (SOMA.CK study)
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Birte, Jessen, primary, Christian, Schmidt-Lauber, additional, Huber, Tobias B., additional, Löwe, Bernd, additional, and Shedden-Mora, Meike, additional
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- 2024
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40. Psychological factors with relevance to Long COVID: A systematic review and meta-analysis
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Petra, Engelmann, primary, Max, Reinke, additional, Clara, Stein, additional, Stefan, Salzmann, additional, Bernd, Löwe, additional, Anne, Toussaint, additional, and Meike, Shedden-Mora, additional
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- 2024
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41. The impact of variations in care and complications within a colorectal Enhanced Recovery After Surgery program on length of stay
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James Wei Tatt Toh, Jack Cecire, Kerry Hitos, Karen Shedden, Fiona Gavegan, Nimalan Pathmanathan, Toufic El Khoury, Angelina Di Re, Annelise Cocco, Alex Limmer, Tom Liang, Kar Yin Fok, James Rogers, Edgardo Solis, and Grahame Ctercteko
- Subjects
enhanced recovery after surgery ,colorectal surgery ,colonic neoplasms ,rectal neoplasms ,Diseases of the digestive system. Gastroenterology ,RC799-869 - Abstract
Purpose Enhanced Recovery After Surgery (ERAS) has become standard of care in colorectal surgery. However, there is not a universally accepted colorectal ERAS protocol and significant variations in care exist between institutions. The aim of this study was to examine the impact of variations in ERAS interventions and complications on length of stay (LOS). Methods This study was a single-center review of the first 200 consecutive patients recruited into our prospectively collected ERAS database. The primary outcome of this study was to examine the rate of compliance to ERAS interventions and the impact of these interventions on LOS. The secondary outcome was to assess the impact of complications (anastomotic leak, ileus, and surgical site infections) on LOS. ERAS interventions, rate of adherence, LOS, readmissions, morbidity, and mortality were recorded, and statistical analysis was performed. Results ERAS variations and complications significantly influenced patient LOS on both univariate and multivariate analysis. ERAS interventions identified as the most important strategies in reducing LOS included laparoscopic surgery, mobilization twice daily postoperative day (POD) 0 to 1, discontinuation of intravenous fluids on POD 0 to 1, upgrading to solid diet by POD 0 to 2, removal of indwelling catheter by POD 0 to 2, avoiding nasogastric tube reinsertion and removing drains early. Both major and minor complications increased LOS. Anastomotic leak and ileus were associated with the greatest increase in LOS. Conclusion Seven high-yield ERAS interventions reduced LOS. Major and minor complications increased LOS. Reducing variations in care and complications can improve outcomes following colorectal surgery.
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- 2022
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42. Supporting staff in healthcare professions to reflect on the emotional aspects of their work
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Shedden, F.
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150 ,BF0636 Applied psychology - Abstract
Background. There is a continued interest around the use of Schwartz Center Rounds© (Rounds) to address the emotional impact of caring for clients. Studies indicate positive outcomes for staff and clients, yet there is a paucity of research exploring how these outcomes occur. This study aimed to understand whether attending Rounds had an impact on how staff perceived themselves and their work. Primarily, it sought to understand what psychological processes may facilitate such an effect and at what point these might occur. Method. Eleven staff members were interviewed about their experience of attending a Round. Grounded theory methodology was used to analyse the interview data. Results. Five key psychological processes of occupying a different space, reciprocity, containment, connection and gaining perspective were identified as facilitating an effect on staffs’ perception of self and work. Processes were fostered during Rounds and seemed to continue afterwards. Discussion. This study is the first to explore psychological processes and build a theoretical model of how Rounds work. Findings can be used to inform the continued implementation of Rounds and facilitator training programmes. Directions for future research are suggested.
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- 2018
43. Optimal group testing designs for estimating prevalence with uncertain testing errors
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Huang, Shih-Hao, Huang, Mong-Na Lo, Shedden, Kerby, and Wong, Weng Kee
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Mathematics - Statistics Theory - Abstract
We construct optimal designs for group testing experiments where the goal is to estimate the prevalence of a trait by using a test with uncertain sensitivity and specificity. Using optimal design theory for approximate designs, we show that the most efficient design for simultaneously estimating the prevalence, sensitivity and specificity requires three different group sizes with equal frequencies. However, if estimating prevalence as accurately as possible is the only focus, the optimal strategy is to have three group sizes with unequal frequencies. On the basis of a chlamydia study in the U.S.A., we compare performances of competing designs and provide insights into how the unknown sensitivity and specificity of the test affect the performance of the prevalence estimator. We demonstrate that the locally D- and Ds-optimal designs proposed have high efficiencies even when the prespecified values of the parameters are moderately misspecified.
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- 2017
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44. The Treatment Expectation Questionnaire (TEX-Q): Validation of a generic multidimensional scale measuring patients' treatment expectations.
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Meike C Shedden-Mora, Jannis Alberts, Keith J Petrie, Johannes A C Laferton, Pia von Blanckenburg, Sebastian Kohlmann, Yvonne Nestoriuc, and Bernd Löwe
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Medicine ,Science - Abstract
BackgroundPatients' expectations, as a central mechanism behind placebo and nocebo effects, are an important predictor of health outcomes. Yet, theoretically based generic assessment tools allowing for an integrated understanding of expectations across conditions and treatments are lacking. Based on the preliminary 35-item version, this study reports the development and validation of the Treatment Expectation Questionnaire (TEX-Q), a generic, multidimensional self-report scale measuring patients' expectations of medical and psychological treatments.MethodsThe TEX-Q was developed in a validation sample of n = 251 patients undergoing different treatments using exploratory factor analyses and item analyses, as well as analysis of convergent and divergent validity. Confirmatory factor analysis was conducted in an independent sample of n = 303 patients undergoing cancer treatment. Two-weeks test-retest reliability was assessed in n = 28 psychosomatic outpatients.ResultsFactor analyses revealed six theoretically founded stable subscales. The TEX-Q assesses expectations of treatment benefit, positive impact, adverse events, negative impact, process and behavioural control with a total of 15 items. Results for the subscales and the sum score indicated good internal consistency (α = .71-.92), moderate to high test-retest reliability (r = .39-.76) as well as good convergent validity with regard to other expectation measures (r = .42-.58) and divergent validity with regard to measures of generalized expectations (r < .32) and psychopathology (r < .28).ConclusionsWhile further validation is needed, the results suggest that the TEX-Q is a valid and reliable scale for the generic, multidimensional assessment of patients' treatment expectations. The TEX-Q overcomes constraints of ad-hoc and disease-specific scales, while allowing to compare the impact of different expectation constructs across conditions and treatments.
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- 2023
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45. Joint mean and covariance estimation with unreplicated matrix-variate data
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Hornstein, Michael, Fan, Roger, Shedden, Kerby, and Zhou, Shuheng
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Statistics - Machine Learning - Abstract
It has been proposed that complex populations, such as those that arise in genomics studies, may exhibit dependencies among observations as well as among variables. This gives rise to the challenging problem of analyzing unreplicated high-dimensional data with unknown mean and dependence structures. Matrix-variate approaches that impose various forms of (inverse) covariance sparsity allow flexible dependence structures to be estimated, but cannot directly be applied when the mean and covariance matrices are estimated jointly. We present a practical method utilizing generalized least squares and penalized (inverse) covariance estimation to address this challenge. We establish consistency and obtain rates of convergence for estimating the mean parameters and covariance matrices. The advantages of our approaches are: (i) dependence graphs and covariance structures can be estimated in the presence of unknown mean structure, (ii) the mean structure becomes more efficiently estimated when accounting for the dependence structure among observations; and (iii) inferences about the mean parameters become correctly calibrated. We use simulation studies and analysis of genomic data from a twin study of ulcerative colitis to illustrate the statistical convergence and the performance of our methods in practical settings. Several lines of evidence show that the test statistics for differential gene expression produced by our methods are correctly calibrated and improve power over conventional methods., Comment: 15 Figures; 79 pages and 4 tables; to appear in the Journal of the American Statistical Association; Technical Report 540, Department of Statistics, University of Michigan; removed condition (A1') and corrected condition (A1) and (A2)
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- 2016
46. Plosive voicing in Afrikaans: Differential cue weighting and tonogenesis
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Coetzee, Andries W, Beddor, Patrice Speeter, Shedden, Kerby, Styler, Will, and Wissing, Daan
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Language ,Communication and Culture ,Language Studies ,Linguistics ,Clinical Research ,Voicing ,Fundamental frequency ,Afrikaans ,Speech perception ,Production-perception relation ,Cue weighting ,Education ,Psychology and Cognitive Sciences ,Speech-Language Pathology & Audiology - Abstract
This study documents the relation between f0 and prevoicing in the production and perception of plosive voicing in Afrikaans. Acoustic data show that Afrikaans speakers differed in how likely they were to produce prevoicing to mark phonologically voiced plosives, but that all speakers produced large and systematic f0 differences after phonologically voiced and voiceless plosives to convey the contrast between the voicing categories. This pattern is mirrored in these same participants’ perception: although some listeners relied more than others on prevoicing as a perceptual cue, all listeners used f0 (especially in the absence of prevoicing) to perceptually differentiate historically voiced and voiceless plosives. This variation in the speech community is shown to be generationally structured such that older speakers were more likely than younger speakers to produce prevoicing, and to rely on prevoicing perceptually. These patterns are consistent with generationally determined differential cue weighting in the speech community and with an ongoing sound change in which the original consonantal voicing contrast is being replaced by a tonal contrast on the following vowel.
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- 2018
47. Brain-wide functional connectivity patterns support general cognitive ability and mediate effects of socioeconomic status in youth
- Author
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Chandra Sripada, Mike Angstadt, Aman Taxali, D. Angus Clark, Tristan Greathouse, Saige Rutherford, Joseph R. Dickens, Kerby Shedden, Arianna M. Gard, Luke W. Hyde, Alexander Weigard, and Mary Heitzeg
- Subjects
Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Abstract General cognitive ability (GCA) is an individual difference dimension linked to important academic, occupational, and health-related outcomes and its development is strongly linked to differences in socioeconomic status (SES). Complex abilities of the human brain are realized through interconnections among distributed brain regions, but brain-wide connectivity patterns associated with GCA in youth, and the influence of SES on these connectivity patterns, are poorly understood. The present study examined functional connectomes from 5937 9- and 10-year-olds in the Adolescent Brain Cognitive Development (ABCD) multi-site study. Using multivariate predictive modeling methods, we identified whole-brain functional connectivity patterns linked to GCA. In leave-one-site-out cross-validation, we found these connectivity patterns exhibited strong and statistically reliable generalization at 19 out of 19 held-out sites accounting for 18.0% of the variance in GCA scores (cross-validated partial η 2). GCA-related connections were remarkably dispersed across brain networks: across 120 sets of connections linking pairs of large-scale networks, significantly elevated GCA-related connectivity was found in 110 of them, and differences in levels of GCA-related connectivity across brain networks were notably modest. Consistent with prior work, socioeconomic status was a strong predictor of GCA in this sample, and we found that distributed GCA-related brain connectivity patterns significantly statistically mediated this relationship (mean proportion mediated: 15.6%, p
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- 2021
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48. Visual-vestibular integration is preserved with healthy aging in a simple acceleration detection task
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Kenney, Darren M., Jabbari, Yasaman, von Mohrenschildt, Martin, and Shedden, Judith M.
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- 2021
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49. Vestibular cues improve landmark-based route navigation: A simulated driving study
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Jabbari, Yasaman, Kenney, Darren M., von Mohrenschildt, Martin, and Shedden, Judith M.
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- 2021
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50. Predictors of somatic symptom persistence in patients with chronic kidney disease (SOMA.CK): study protocol for a mixed-methods cohort study
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Bernd Löwe, Christian Schmidt-Lauber, Omer Van den Bergh, Tobias B Huber, Meike C Shedden-Mora, Birte Jessen, Michael Rösch, Hendrik Dannemeyer, and Joachim Gloy
- Subjects
Medicine - Abstract
Introduction Seven of 10 patients with non-dialysis chronic kidney disease (CKD) experience burdensome persistent somatic symptoms (PSS). Despite the high prevalence and relevance for quality of life, disease progression and mortality, the pathogenesis of PSS in CKD remains poorly understood. The SOMA.CK study aims to investigate biopsychosocial predictors and their interactions for PSS in non-dialysis CKD and to develop a multivariate prognostic prediction model for PSS in CKD.Methods and analysis The study is a mixed-methods cohort study with assessments at baseline, 6 and 12 months. It aims to include 330 patients with CKD stages G2–4 (eGFR=15–89 mL/min/1.73 m2). Primary outcome is the CKD-specific somatic symptom burden assessed with the CKD Symptom Burden Index. Secondary outcomes include quality of life, general somatic symptom burden and functioning. The interplay of biomedical (eg, biomarkers, epigenetics), treatment-related (eg, therapies and medication) and psychosocial variables (eg, negative affectivity, expectations) will be investigated to develop a prognostic prediction model for PSS. In an embedded mixed-methods approach, an experimental study in 100 patients using an affective picture paradigm will test the effect of negative affect induction on symptom perception. An embedded longitudinal qualitative study in 40–50 newly diagnosed patients will use thematic analysis to explore mechanisms of symptom development after receiving a CKD diagnosis. SOMA.CK is part of the interdisciplinary research unit ‘Persistent SOMAtic Symptoms ACROSS Diseases’.Ethics and dissemination The study was approved by the Ethics Committee of the Hamburg Medical Association (2020-10195-BO-ff). Findings will be disseminated through peer-reviewed publications, scientific conferences, the involvement of our patient advisory board and the lay public. Focusing on subjective symptom burden instead of objective disease markers will fundamentally broaden the understanding of PSS in CKD and pave the path for the development of mechanism-based tailored interventions.Trial registration number ISRCTN16137374.
- Published
- 2022
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