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This innovative approach to teaching the finite element method blends theoretical, textbook-based learning with practical application using online and video resources. This hybrid teaching package features computational software such as MATLAB®, and tutorials presenting software applications such as PTC Creo Parametric, ANSYS APDL, ANSYS Workbench and SolidWorks, complete with detailed annotations and instructions so students can confidently develop hands-on experience. Suitable for senior undergraduate and graduate level classes, students will transition seamlessly between mathematical models and practical commercial software problems, empowering them to advance from basic differential equations to industry-standard modelling and analysis. Complete with over 120 end-of chapter problems and over 200 illustrations, this accessible reference will equip students with the tools they need to succeed in the workplace.
To develop a pediatric research agenda focused on pediatric healthcare-associated infections and antimicrobial stewardship topics that will yield the highest impact on child health.
The study included 26 geographically diverse adult and pediatric infectious diseases clinicians with expertise in healthcare-associated infection prevention and/or antimicrobial stewardship (topic identification and ranking of priorities), as well as members of the Division of Healthcare Quality and Promotion at the Centers for Disease Control and Prevention (topic identification).
Using a modified Delphi approach, expert recommendations were generated through an iterative process for identifying pediatric research priorities in healthcare associated infection prevention and antimicrobial stewardship. The multistep, 7-month process included a literature review, interactive teleconferences, web-based surveys, and 2 in-person meetings.
A final list of 12 high-priority research topics were generated in the 2 domains. High-priority healthcare-associated infection topics included judicious testing for Clostridioides difficile infection, chlorhexidine (CHG) bathing, measuring and preventing hospital-onset bloodstream infection rates, surgical site infection prevention, surveillance and prevention of multidrug resistant gram-negative rod infections. Antimicrobial stewardship topics included β-lactam allergy de-labeling, judicious use of perioperative antibiotics, intravenous to oral conversion of antimicrobial therapy, developing a patient-level “harm index” for antibiotic exposure, and benchmarking and or peer comparison of antibiotic use for common inpatient conditions.
We identified 6 healthcare-associated infection topics and 6 antimicrobial stewardship topics as potentially high-impact targets for pediatric research.
This is the first report on the association between trauma exposure and depression from the Advancing Understanding of RecOvery afteR traumA(AURORA) multisite longitudinal study of adverse post-traumatic neuropsychiatric sequelae (APNS) among participants seeking emergency department (ED) treatment in the aftermath of a traumatic life experience.
We focus on participants presenting at EDs after a motor vehicle collision (MVC), which characterizes most AURORA participants, and examine associations of participant socio-demographics and MVC characteristics with 8-week depression as mediated through peritraumatic symptoms and 2-week depression.
Eight-week depression prevalence was relatively high (27.8%) and associated with several MVC characteristics (being passenger v. driver; injuries to other people). Peritraumatic distress was associated with 2-week but not 8-week depression. Most of these associations held when controlling for peritraumatic symptoms and, to a lesser degree, depressive symptoms at 2-weeks post-trauma.
These observations, coupled with substantial variation in the relative strength of the mediating pathways across predictors, raises the possibility of diverse and potentially complex underlying biological and psychological processes that remain to be elucidated in more in-depth analyses of the rich and evolving AURORA database to find new targets for intervention and new tools for risk-based stratification following trauma exposure.
Supported by (1) medical research grants CMRPG3C0041/42 from Chang Gung Memorial Hospital and NRRPG2H0031 from Ministry of Science and Technology, Taiwan to Chemin Lin (2) NMRPG3G6031/32 from Ministry of Science and Technology, Taiwan to Shwu-Hua, Lee (3) the KKHo International Charitable Foundation to Tatia Lee.
Suicide rate tends to peak in old age, and major depression is the most salient risk factor for late-life suicide. However, few studies have focused on the neuroscientific facet of suicide in the context of late-life depression (LLD).
We recruited 114 participants of LLD (28 with history of suicide attempt and 86 without) and 47 elderly controls. They received MRI scanning and behavioral assessment. White matter hyperintensity (WMH) was quantified by an automated segmentation algorithm and graph theoretical analysis was applied to resting-state fMRI. We used ANCOVA to compare group difference in WMH loading and multivariate generalized linear model to compare global and local topological parameters in fMRI signals, controlling for demographics. Partial correlation was conducted between imaging parameters and behavioral data in group of suicide attempters.
We found significant higher WMH in suicide attempters than those of LLD without suicide attempts and elderly controls (F =7.091; p = 0.001). Suicide attempters also had increased betweenness centrality (BC) in right superior occipital gyrus (SOG) (Bonferroni corrected), right precuneus (False positive corrected) and right superior temporal gyrus (uncorrected) and decreased BC in left hippocampus (uncorrected). In suicide attempters, higher BC in right SOG correlated with higher WMH, higher depression severity, higher illness awareness and insight, and lower cognitive function (digit backward), while higher BC in right precuneus correlated with higher decrease awareness and insight and higher cognitive function (digit backward).
Resonating with the vascular hypothesis in LLD, higher WMH was found in those having history of suicide attempts. However, the re-organized brain topology changes are related with divergent cognitive function and convergent heightened disease insight.
Background: Nosocomial central-line–associated bloodstream infections (CLABSIs) are an important cause of morbidity and mortality in hospitalized patients. CLABSI surveillance establishes rates for internal and external comparison, identifies risk factors, and allows assessment of interventions. Objectives: To determine the frequency of CLABSIs among adult patients admitted to intensive care units (ICUs) in CNISP hospitals and evaluate trends over time. Methods: CNISP is a collaborative effort of the Canadian Hospital Epidemiology Committee, the Association of Medical Microbiologists and Infectious Disease Canada and the Public Health Agency of Canada. Since 1995, CNISP has conducted hospital-based sentinel surveillance of healthcare-associated infections. Overall, 55 CNISP hospitals participated in ≥1 year of CLABSI surveillance. Adult ICUs are categorized as mixed ICUs or cardiovascular (CV) surgery ICUs. Data were collected using standardized definitions and collection forms. Line-day denominators for each participating ICU were collected. Negative-binomial regression was used to test for linear trends, with robust standard errors to account for clustering by hospital. We used the Fisher exact test to compare binary variables. Results: Each year, 28–42 adult ICUs participated in surveillance (27–37 mixed, 6–8 CV surgery). In both mixed ICUs and CV-ICUs, rates remained relatively stable between 2011 and 2018 (Fig. 1). In mixed ICUs, CLABSI rates were 1.0 per 1,000 line days in 2011, and 1.0 per 1,000 line days in 2018 (test for linear trend, P = .66). In CV-ICUs, CLABSI rates were 1.1 per 1,000 line days in 2011 and 0.8 per 1,000 line days in 2018 (P = .19). Case age and gender distributions were consistent across the surveillance period. The 30-day all-cause mortality rate was 29% in 2011 and in 2018 (annual range, 29%–35%). Between 2011 and 2018, the percentage of isolated microorganisms that were coagulase-negative staphylococci (CONS) decreased from 31% to 18% (P = .004). The percentage of other gram-positive organisms increased from 32% to 37% (P = .34); Bacillus increased from 0% to 4% of isolates and methicillin-susceptible Staphylococcus aureus from 2% to 6%). The gram-negative organisms increased from 21% to 27% (P = .19). Yeast represented 16% in 2011 and 18% in 2018; however, the percentage of yeast that were Candida albicans decreased over time (58% of yeast in 2011 and 30% in 2018; P = .04). Between 2011 and 2018, the most commonly identified species of microorganism in each year were CONS (18% in 2018) and Enterococcus spp (18% in 2018). Conclusions: Ongoing CLABSI surveillance has shown stable rates of CLABSI in adult ICUs from 2011 to 2018. The causative microorganisms have changed, with CONS decreasing from 31% to 18%.
Funding: CNISP is funded by the Public Health Agency of Canada.
Disclosures: Allison McGeer reports funds to her for studies, for which she is the principal investigator, from Pfizer and Merck, as well as consulting fees from Sanofi-Pasteur, Sunovion, GSK, Pfizer, and Cidara.
A study of low-speed streaks (LSSs) embedded in the near-wall region of a turbulent boundary layer is performed using selective visualization and analysis of time-resolved tomographic particle image velocimetry (tomo-PIV). First, a three-dimensional velocity field database is acquired using time-resolved tomo-PIV for an early turbulent boundary layer. Second, detailed time-line flow patterns are obtained from the low-order reconstructed database using ‘tomographic visualizations’ by Lagrangian tracking. These time-line patterns compare remarkably well with previously observed patterns using hydrogen bubble flow visualization, and allow local identification of LSSs within the database. Third, the flow behaviour in proximity to selected LSSs is examined at varying wall distances (
$10 < y^+ < 100$
) and assessed using time-line and material surface evolution, to reveal the flow structure and evolution of a streak, and the flow structure evolving from streak development. It is observed that three-dimensional wave behaviour of the detected LSSs appears to develop into associated near-wall vortex flow structures, in a process somewhat similar to transitional boundary layer behaviour. Fourth, the presence of Lagrangian coherent structures is assessed in proximity to the LSSs using a Lagrangian-averaged vorticity deviation process. It is observed that quasi-streamwise vortices, adjacent to the sides of the streak-associated three-dimensional wave, precipitate an interaction with the streak. Finally, a hypothesis based on the behaviour of soliton-like coherent structures is made which explains the process of LSS formation, bursting behaviour and the generation of hairpin vortices. Comparison with other models is also discussed.
Investigation of treatments that effectively treat adults with post-traumatic stress disorder from childhood experiences (Ch-PTSD) and are well tolerated by patients is needed to improve outcomes for this population.
The purpose of this study was to compare the effectiveness of two trauma-focused treatments, imagery rescripting (ImRs) and eye movement desensitisation and reprocessing (EMDR), for treating Ch-PTSD.
We conducted an international, multicentre, randomised clinical trial, recruiting adults with Ch-PTSD from childhood trauma before 16 years of age. Participants were randomised to treatment condition and assessed by blind raters at multiple time points. Participants received up to 12 90-min sessions of either ImRs or EMDR, biweekly.
A total of 155 participants were included in the final intent-to-treat analysis. Drop-out rates were low, at 7.7%. A generalised linear mixed model of repeated measures showed that observer-rated post-traumatic stress disorder (PTSD) symptoms significantly decreased for both ImRs (d = 1.72) and EMDR (d = 1.73) at the 8-week post-treatment assessment. Similar results were seen with secondary outcome measures and self-reported PTSD symptoms. There were no significant differences between the two treatments on any standardised measure at post-treatment and follow-up.
ImRs and EMDR treatments were found to be effective in treating PTSD symptoms arising from childhood trauma, and in reducing other symptoms such as depression, dissociation and trauma-related cognitions. The low drop-out rates suggest that the treatments were well tolerated by participants. The results from this study provide evidence for the use of trauma-focused treatments for Ch-PTSD.
Several decades of basic research support the neural basis of multiple memory systems. These systems are highly relevant to all health behaviors, since behaviors are learned from experience and require some form of memory process to retain learning and affect subsequent action. Research on the neuroscience of appetitive behaviors has rigorously studied motivational processes involved in behaviors such as drug use, diet, and sex. However, very little of this otherwise stellar research has attempted to integrate its findings with multiple memory system views that acknowledge the wide range of memory effects uncovered in several highly relevant basic research areas. Further, good explanatory theories of multiple memory systems studied mostly in addiction and in animal research have not yet been integrated with the vast knowledge base from human cognitive science. Moreover, most research on the epidemiology, prevention, or treatment of problems in appetitive behavior has not taken into account these basic research findings and has instead focused on theories and methods derived primarily from survey research. Yet, basic research areas from neuroscience and cognitive science are highly relevant to all areas of study of appetitive behavior, and the prevailing focus in prevention science on concepts derived from survey research may be channeled mostly by the training of investigators and disciplinary history. This chapter provides one example of how these disparate literatures from basic research might be integrated to advance our understanding of this class of behavior and derive new possibilities for intervention. It highlights examples of key findings supporting the need for a greater translational effort but also highlights large gaps in knowledge. Future research filling these gaps and others in the void between compelling research domains could substantially change and advance the study of addictions and all appetitive or habit-forming behaviors.
The events surrounding the prodemocracy movement in Hong Kong from 2013 to 2015 represent the latest chapter in a long and torturous struggle for democracy that can be dated back to the early 1980s when Britain and China held their negotiations over the city’s future (So, 1998). The Occupy Central Movement (OCM), initiated by three prodemocracy activists, exhorted supporters to block major roads and exercise civil disobedience in the struggle for full democracy. It soon provoked the Chinese Communist Party-state (“party-state”) to initiate a campaign to counter OCM. Executed mainly through their unofficial agents and sponsored organizations in Hong Kong, its scale of operation was almost unprecedented, at least since the social riot in 1967 (which was largely the spillover of the Cultural Revolution).
Biogas digesters convert waste matter into a natural gas-like fuel and a nutrient-rich digestate by-product. This digestate has the potential to be used as a soil amendment to benefit crop production with or without biochar, a purported nutrient sponge. In a greenhouse study of several crop species, the effects of digestate fertilization on crop growth, photosynthetic efficiency, vegetable production and chemical nutrient levels were tested. Results indicate that increasing potency of the applied digestate fosters higher growth and fruit production rates of several studied plants but to a lesser degree than a conventional fertilizer. More potent digestate application increases antioxidant capacity, total phenolics content and ascorbic acid levels in kale compared to the control chemical fertilizer test groups but has confounding results on legume nutrient levels. Additionally, the combined application of biochar and biogas digestate added to compost and used as potting media positively impacts crop germination. This work has relevance to agrarian communities that could benefit from recycling livestock and food waste into fuel and a renewable fertilizer.
For CHD patients undergoing corrective surgery utilising cardiopulmonary bypass, post-operative inhaled nitric oxide has been administered to alleviate pulmonary hypertension. We performed a systematic review and meta-analyses to determine the effect of inhaled nitric oxide on haemodynamics, gas exchange, and hospitalisation characteristics in children immediately after cardiopulmonary bypass.
Materials and methods:
A systematic review of the literature was performed to identify full-text manuscripts in English. PubMed, EMBASE, and the Cochrane databases were queried. Once manuscripts were identified for inclusion, a list of all the endpoints in each manuscript was created. Endpoints with data present from two or more studies were then kept for pooled analyses. All endpoints included were continuous variables and so mean and standard deviation were utilised as the effect data for comparison.
A total of eight studies were deemed appropriate for inclusion. There were significant differences with decreases in mean pulmonary artery pressure of −6.82 mmHg, left atrial pressure of −1.16 mmHg, arteriovenous oxygen difference of −1.63, arterial carbon dioxide concentration of −2.41 mmHg, mechanical ventilation duration of −8.56 hours, and length of cardiac ICU stay duration of −0.91 days. All significant variables achieved p < 0.001.
Inhaled nitric oxide in children immediately after cardiopulmonary bypass decreases mean pulmonary artery pressure significantly and decreases the arterial carbon dioxide concentration significantly without significantly altering other haemodynamic parameters. This results in a statistically shorter duration of mechanical ventilation and cardiac ICU length of stay without altering overall hospital length of stay.
Previous research has suggested an association between depression and subsequent acute stroke incidence, but few studies have examined any effect modification by sociodemographic factors. In addition, no studies have investigated this association among primary care recipients with hypertension.
We examined the anonymized records of all public general outpatient visits by patients aged 45+ during January 2007–December 2010 in Hong Kong to extract primary care patients with hypertension for analysis. We took the last consultation date as the baseline and followed them up for 4 years (until 2011–2014) to observe any subsequent acute hospitalization due to stroke. Mixed-effects Cox models (random intercept across 74 included clinics) were implemented to examine the association between depression (ICPC diagnosis or anti-depressant prescription) at baseline and the hazard of acute stroke (ICD-9: 430–437.9). Effect modification by age, sex, and recipient status of social security assistance was examined in extended models with respective interaction terms specified.
In total, 396 858 eligible patients were included, with 9099 (2.3%) having depression, and 10 851 (2.7%) eventually hospitalized for stroke. From the adjusted analysis, baseline depression was associated with a 17% increased hazard of acute stroke hospitalization [95% confidence interval (CI) 1.03–1.32]. This association was suggested to be even stronger among men than among women (hazard ratio = 1.29, 95% CI 1.00–1.67).
Depression is more strongly associated with acute stroke incidence among male than female primary care patients with hypertension. More integrated services are warranted to address their needs.
“C-K theory”, a theory of reasoning in design, offers a formal modelling language with the power to describe the unfolding of creativity and the generation of new innovative objects as integral parts of design practice. However, the theory has limited ability to analyze and describe the particulars of design practice when the target area is service. To address this question, the purpose of this paper is to refine the “C-K theory” by embedding service relevant constructs and exploring strategies for enhancing the creative engagement resulting in the innovative service concepts.
Patulous Eustachian tube appears to be caused by a concave defect in the anterolateral wall of the tubal valve of the Eustachian tube. This study aimed to compare the clinical features of patulous Eustachian tube patients with or without a defect in the anterolateral wall of the tubal valve.
Sixty-six patients with a patulous Eustachian tube completed a questionnaire, which was evaluated alongside endoscopic findings of the tympanic membrane, nasal cavity and Eustachian tube orifice.
Females were more frequently diagnosed with a patulous Eustachian tube, but the valve defect was more common in males (p = 0.007). The ratio of patulous Eustachian tube patients with or without defects in the anterolateral wall of the tubal valve was 1.6:1. Weight loss in the previous six months and being refractory to conservative management were significantly associated with the defect (p = 0.035 and 0.037, respectively). Symptom severity was significantly higher in patients with the defect.
Patulous Eustachian tube patients without a defect in the anterolateral wall of the tubal valve can be non-surgically treated more often than those with the defect. Identification of the defect could assist in making treatment decisions for patulous Eustachian tube patients.
To inform the efficient allocation of testing resources, we evaluated the characteristics of those tested for COVID-19 to determine predictors of a positive test. Recent travel and exposure to a confirmed case were both highly predictive of positive testing. Symptom-based screening strategies alone may be inadequate to control the ongoing pandemic.
Experimental work has revealed causal links between physical cleansing and various psychological variables. Empirically, how robust are they? Theoretically, how do they operate? Major prevailing accounts focus on morality or disgust, capturing a subset of cleansing effects, but cannot easily handle cleansing effects in non-moral, non-disgusting contexts. Building on grounded views on cognitive processes and known properties of mental procedures, we propose grounded procedures of separation as a proximate mechanism underlying cleansing effects. This account differs from prevailing accounts in terms of explanatory kind, interpretive parsimony, and predictive scope. Its unique and falsifiable predictions have received empirical support: Cleansing attenuates or eliminates otherwise observed influences of prior events (1) across domains and (2) across valences. (3) Cleansing manipulations produce stronger effects the more strongly they engage sensorimotor capacities. (4) Reversing the causal arrow, motivation for cleansing is triggered more readily by negative than positive entities. (5) Conceptually similar effects extend to other physical actions of separation. On the flipside, grounded procedures of connection are also observed. Together, separation and connection organize prior findings relevant to multiple perspectives (e.g., conceptual metaphor, sympathetic magic) and open up new questions. Their predictions are more generalizable than the specific mappings in conceptual metaphors, but more fine-grained than the broad assumptions of grounded cognition. This intermediate level of analysis sheds light on the interplay between mental and physical processes.
Introduction: Assessment of point-of-care ultrasound (POCUS) competency has been reliant on practical, visual and written examinations performed 1-on-1 with an examiner. These tools attempt to assess competency through subjective ratings, checklists and multiple-choice questions that are labour intensive using surrogate measures. Eye-tracking has been used on a limited basis in various fields of medicine for training and assessment. This technology explores visual processing and holds great promise as a tool to monitor training progress towards the development of expertise. We hypothesize that eye-tracking may differentiate novices and experts as they progress to become competent in interpretation of POCUS images and provide an objective measure in assessment of competency. Methods: Medical students, residents and attending physicians working in an academic emergency department were recruited. Participants viewed a series of 16 ultrasound video clips in a POCUS protocol for Focused Assessment using Sonography in Trauma (FAST). The gaze pattern of the participants was recorded using a commercially available eye-tracking device. The primary outcome was the gaze parameters including total gaze time in the area of interest (AOI), average time to fixation on the AOI, number of fixations in the AOI and average duration of first fixation on the AOI. Secondary outcome was the accuracy on the interpretation of the FAST scan. Results: Four novices and eight experts completed this study. The total gaze time in the AOI (mean +/- SD) was 76.72 +/- 18.84s among experts vs 53.64 +/- 10.33s among novices (p = 0.048), average time to fixation on the AOI was 0.561 +/- 0.319s vs 1.048 +/- 0.280s (p = 0.027), number of fixations in the AOI was 158.9 +/- 29.0 vs 121.8 +/- 17.5 (p = 0.042) and average duration of first fixation was 0.444 +/- 0.119s vs 0.390 +/- 0.024s (p = 0.402). The accuracy of the answers was 79.7 +/- 14.1% vs 45.3 +/- 21.9% (p = 0.007). Conclusion: In this pilot study, eye tracking shows potential to differentiate between POCUS experts and novices by their gaze patterns. Gaze patterns captured by eye tracking may not necessarily translate to cognitive processing. However, it allows educators to visualise the thought processes of the learner by their gaze patterns and provide insight on how to guide them towards competency. Future studies are needed to further validate the metrics for competency in POCUS applications.
Cardiac surgery induces profound sympathetic nervous system and inflammatory responses. This so-called ‘stress response’ to surgery causes a multitude of adverse haemodynamic, metabolic, haematological, endocrine and immunological effects. In the setting of cardiac surgery, the attenuation of pain and sympathetic autonomic activity has many theoretical attractions. The introduction of high-dose opioid techniques into cardiac anaesthesia was based, in part, on the belief that they would inhibit the stress response. Failure to block the stress response completely, combined with equivocal evidence of clinical benefit and the need for prolonged postoperative mechanical ventilation, made the technique unpopular. The demonstration that thoracic sympathetic blockade improves the blood flow in severely diseased coronary arteries, the emergence of less invasive cardiac surgical techniques and economic pressures have prompted renewed interest in regional anaesthetic techniques.
Prior tests of Hicks’ Induced Innovation Hypothesis (IIH) have been greatly hampered because the lack of supply-side data implicitly requires the untenable assumption that the marginal research cost is the same for different inputs. We document that, with appropriate model specification and panel data, a two-way fixed-effects estimator can account for much of the non-neutrality of the innovation function. Using a test procedure that is robust to a time-variant and non-neutral innovation function, we test the IIH in U.S. agriculture for the period 1960–2004. We use only readily available data for innovation demand and total public research expenditures.