Teaching Tracheostomy Tube Changes: Comparison of Operant Learning Versus Traditional Demonstration.

Objective: Tracheostomy tube change is a multistep skill that must be performed rapidly and precisely. Despite the critical importance of this skill, there is wide variation in teaching protocols. Methods: An innovative operant conditioning teaching methodology was employed and compared to traditional educational techniques. Medical student volunteers at a tertiary care academic institution (Albert Einstein College of Medicine) were recruited and randomly distributed into 2 groups: operant vs traditional (control). Following the educational session, each group was provided with practice time and then asked to perform 10 tracheostomy tube changes. Performance was recorded and scored by blinded raters using deidentified video recordings. Results: The operant learning group (OLG) demonstrated greater accuracy in performing a tracheostomy tube change than the traditional demonstration group. Twelve of 13 operant learners performed the skill accurately each time compared to 3 of 13 in the traditional group (P = 0.002). The median lesson time was longer for the OLG (535 seconds) than for the traditional group, (200 seconds P < 0.001). The average time per tracheostomy change was not significantly different between the 2 groups (operant learners mean 7.1 seconds, traditional learners mean 7.5 seconds, P = 0.427). Discussion: Although the operant conditioning methodology necessarily requires a greater time to teach, the results support this methodology over traditional learning modalities as it enhances accuracy in the acquired skill. Operant learning methodology is under consideration for other skills and education sessions in our program. Future steps include the application and adaptation of this education model to students and residents in other settings and fields. Implications for Practice: Operant learning is effective for teaching multistep skills such as tracheostomy tube changes with decreased error rates.

Modified VMAT Plans for Locally Advanced Centrally Located Non-Small Cell Lung Cancer (NSCLC).

OBJECTIVES: This study aimed to find the optimal radiotherapy VMAT plans, that achieved high conformity and homogeneity to the planned target volume (PTV), and minimize the dose to nearby organs at risk including the non-PTV lung, heart and oesophagus for patients with centrally located non-small Cell Lung Cancer. METHODS: A total of 18 patients who were treated for stage III centrally located non-small Cell Lung Cancer were selected retrospectively for this study. Identical CT datasets, 4D CT and structure dataset were used for radiotherapy planning based on single-planar VMAT (SP-VMAT), dual-planar VMAT (DP-VMAT) and Hybrid VMAT (H-VMAT). For SP-VMAT, one full arc and two half arcs were created on single-plane with couch at 0°. For DP-VMAT, one full arc was created with couch at 0°, and two half arcs with couch rotation of 330° or 30°. For H-VMAT, anterior-posterior opposing fixed beam and two half arcs were planned at couch at 0°. Dose constraints were adhered to the RTOG0617. Dose volumetric parameters were collected for statistical analysis. RESULTS: There were no significant differences for the PTV, HI, CI between the SP-VMAT, DP-VMAT and H-VMAT. For the non-PTV lungs, Dmean, V20, V10, V5, D1500 and D1000 were significantly lower (2.05 Gy, 6.47%, 15.89%, 11.66% 4.17 Gy and 5.47 Gy respectively) in H-VMAT than that of SP-VMAT (all p < 0.001). For the oesophagus, Dmax, Dmean, V30 and V18.8 of H-VMAT were 0.08 Gy, 1.73 Gy, 5.54% and 7.17% lower than that of the SP-VMAT plan. For the heart, Dmean, V34, V28, V20 and V10 of DP-VMAT were lower than that of SP-VMAT by 1.45 Gy, 0.65%, 1.74%, 4.8% and 7.11% respectively. CONCLUSION: The proposed H-VMAT showed more favourable plan quality than the SP-VMAT for centrally located stage III NSCLC, in particular for non-PTV lungs and the oesophagus. It will benefit patients, especially those who planned for immunotherapy (Durvalumab) after standard chemo-irradiation. The proposed DP-VMAT plan showed significant dose reduction to the heart when compared to the H-VMAT plan.

Roles of Cholesterol in Early and Late Steps of the Nipah Virus Membrane Fusion Cascade.

Cholesterol has been implicated in various viral life cycle steps for different enveloped viruses, including viral entry into host cells, cell-cell fusion, and viral budding from infected cells. Enveloped viruses acquire their membranes from their host cells. Although cholesterol has been associated with the binding and entry of various enveloped viruses into cells, cholesterol's exact function in the viral-cell membrane fusion process remains largely elusive, particularly for the paramyxoviruses. Furthermore, paramyxoviral fusion occurs at the host cell membrane and is essential for both virus entry (virus-cell fusion) and syncytium formation (cell-cell fusion), central to viral pathogenicity. Nipah virus (NiV) is a deadly member of the Paramyxoviridae family, which also includes Hendra, measles, mumps, human parainfluenza, and various veterinary viruses. The zoonotic NiV causes severe encephalitis, vasculopathy, and respiratory symptoms, leading to a high mortality rate in humans. We used NiV as a model to study the role of membrane cholesterol in paramyxoviral membrane fusion. We used a combination of methyl-beta cyclodextrin (MßCD), lovastatin, and cholesterol to deplete or enrich cell membrane cholesterol outside cytotoxic concentrations. We found that the levels of cellular membrane cholesterol directly correlated with the levels of cell-cell fusion induced. These phenotypes were paralleled using NiV/vesicular stomatitis virus (VSV)-pseudotyped viral infection assays. Remarkably, our mechanistic studies revealed that cholesterol reduces an early F-triggering step but enhances a late fusion pore formation step in the NiV membrane fusion cascade. Thus, our results expand our mechanistic understanding of the paramyxoviral/henipaviral entry and cell-cell fusion processes.IMPORTANCE Cholesterol has been implicated in various steps of the viral life cycle for different enveloped viruses. Nipah virus (NiV) is a highly pathogenic enveloped virus in the Henipavirus genus within the Paramyxoviridae family, capable of causing a high mortality rate in humans and high morbidity in domestic and agriculturally important animals. The role of cholesterol for NiV or the henipaviruses is unknown. Here, we show that the levels of cholesterol influence the levels of NiV-induced cell-cell membrane fusion during syncytium formation and virus-cell membrane fusion during viral entry. Furthermore, the specific role of cholesterol in membrane fusion is not well defined for the paramyxoviruses. We show that the levels of cholesterol affect an early F-triggering step and a late fusion pore formation step during the membrane fusion cascade. Thus, our results expand our mechanistic understanding of the viral entry and cell-cell fusion processes, which may aid the development of antivirals.

Cueing healthier alternatives for take-away: a field experiment on the effects of (disclosing) three nudges on food choices.

BACKGROUND: The current field experiment demonstrates the effectiveness of nudging to promote healthy food choices. METHODS: Three types of nudges were implemented at a take-away food vendor: 1) an accessibility nudge that placed fruits at the front counter; 2) a salience nudge that presented healthy bread rolls to be more visually attractive; and 3) a social proof nudge that conveyed yoghurt as a popular choice. We additionally assessed whether nudging effects would remain robust when a disclosure message was included. The field experiment was conducted over a seven-week period. The measured outcome was the sales of the targeted healthy food products. RESULTS: The accessibility nudge significantly increased the sales of the fresh fruits. The impact of the salience nudge was limited presumably due to existing preferences or habits that typically facilitate bread purchases. As the sales of the yoghurt shakes remained consistently low over the seven-week period the impact of the social proof nudge remained unexamined. Critically, disclosing the purpose of the nudges did not interfere with effects. CONCLUSIONS: Current findings suggest nudging as an effective strategy for healthy food promotion, and offer implications for topical debate regarding the ethics of nudges.

The Hunger Games: Using hunger to promote healthy choices in self-control conflicts.

The majority of existing research and conventional wisdom would advise against shopping on an empty stomach as hunger is assumed to encourage impulsive choices that typically lead to self-control failure (i.e., favouring short-term gratifications at the expense of long-term goals). Nonetheless, through two studies the current research aims to demonstrate that hungry consumers would not always be disadvantaged when encountering a self-control conflict involving a trade-off choice between a healthy vs. a more palatable but unhealthy choice. Particularly we posit that the choice outcome of the self-control conflict is dependent on contextual cues, such that hungry consumers with the tendency to make fast decisions could benefit from following a social proof heuristic promoting the healthy options. In Study 1, we indeed observed participants' self-reported hunger to be negatively associated with state self-control, but as most participants generally experienced low levels of hunger we did not observe apparent effects of hunger on food choice (DV), and correspondingly the potential influence of the social proof heuristic in moderating the choice outcome. However, in Study 2 where hunger was manipulated, we found hungry participants making significantly less healthy choices than satiated participants, but a social proof heuristic mitigated this effect (i.e., in the presence of social proof heuristic hungry participants made just as many healthy food choices as satiated participants; and hungry participants made more healthy choices in the social proof condition than in the no heuristic condition). These findings support our approach of providing contextual cues in the environment in order to work with, rather than against, the impulsivity triggered by hunger to promote successful self-control behaviours.

Ability of mini-implant-facilitated micro-osteoperforations to accelerate tooth movement in rats.

INTRODUCTION: Although current techniques for accelerated tooth movement often involve invasive surgical procedures, micro-osteoperforations (MOPs) using mini-implants may facilitate orthodontic tooth movement without raising flaps, reduce surgical risks, and increase patient acceptance. In this study, we evaluated the effectiveness of mini-implant-facilitated MOPs in inducing accelerated tooth movement and investigated the potential risks for root resorption. METHODS: Five MOPs were placed on the left side around the maxillary first molars in 6 rats using an automated mini-implant driver, whereas the right side received no MOPs as the control. Closed-coiled springs were secured from incisors to first molars for orthodontic tooth movement. Tooth movement was measured, and samples underwent radiologic and histologic analyses. RESULTS: The MOP side exhibited a 1.86-fold increase in the rate of tooth movement with decreased bone density and bone volume around the first molars compared with the control side. Hematoxylin and eosin and tartrate-resistant acid phosphatase analyses showed increased numbers of osteoclasts as well as new bone formation. Three-dimensional volumetric analysis of all 5 roots of the maxillary first molars demonstrated no statistically significant difference in root volumes. CONCLUSIONS: Mini-implant-facilitated MOPs accelerated tooth movement without increased risk for root resorption and therefore may become a readily available and efficient treatment option to shorten orthodontic treatment time with improved patient acceptance.

A Multilab Preregistered Replication of the Ego-Depletion Effect.

Good self-control has been linked to adaptive outcomes such as better health, cohesive personal relationships, success in the workplace and at school, and less susceptibility to crime and addictions. In contrast, self-control failure is linked to maladaptive outcomes. Understanding the mechanisms by which self-control predicts behavior may assist in promoting better regulation and outcomes. A popular approach to understanding self-control is the strength or resource depletion model. Self-control is conceptualized as a limited resource that becomes depleted after a period of exertion resulting in self-control failure. The model has typically been tested using a sequential-task experimental paradigm, in which people completing an initial self-control task have reduced self-control capacity and poorer performance on a subsequent task, a state known as ego depletion Although a meta-analysis of ego-depletion experiments found a medium-sized effect, subsequent meta-analyses have questioned the size and existence of the effect and identified instances of possible bias. The analyses served as a catalyst for the current Registered Replication Report of the ego-depletion effect. Multiple laboratories (k = 23, total N = 2,141) conducted replications of a standardized ego-depletion protocol based on a sequential-task paradigm by Sripada et al. Meta-analysis of the studies revealed that the size of the ego-depletion effect was small with 95% confidence intervals (CIs) that encompassed zero (d = 0.04, 95% CI [-0.07, 0.15]. We discuss implications of the findings for the ego-depletion effect and the resource depletion model of self-control.

Endothelial Cell Senescence Increases Traction Forces due to Age-Associated Changes in the Glycocalyx and SIRT1.

Endothelial cell (EC) aging and senescence are key events in atherogenesis and cardiovascular disease development. Age-associated changes in the local mechanical environment of blood vessels have also been linked to atherosclerosis. However, the extent to which cell senescence affects mechanical forces generated by the cell is unclear. In this study, we sought to determine whether EC senescence increases traction forces through age-associated changes in the glycocalyx and antioxidant regulator deacetylase Sirtuin1 (SIRT1), which is downregulated during aging. Traction forces were higher in cells that had undergone more population doublings and changes in traction force were associated with altered actin localization. Older cells also had increased actin filament thickness. Depletion of heparan sulfate in young ECs elevated traction forces and actin filament thickness, while addition of heparan sulfate to the surface of aged ECs by treatment with angiopoietin-1 had the opposite effect. While inhibition of SIRT1 had no significant effect on traction forces or actin organization for young cells, activation of SIRT1 did reduce traction forces and increase peripheral actin in aged ECs. These results show that EC senescence increases traction forces and alters actin localization through changes to SIRT1 and the glycocalyx.

Under consumers' scrutiny - an investigation into consumers' attitudes and concerns about nudging in the realm of health behavior.

BACKGROUND: Nudging strategies have recently attracted attention from scholars and policy makers for their potential in influencing people's behaviors on large scales. But is the fact that nudges do not forbid any choice-options or significantly alter people's economic incentives sufficient to conclude that nudges should be implemented? While this is discussed amongst scholars from various disciplines the voices of consumers, the target-group of nudges, remain unheard. Since understanding their knowledge about nudging and their opinions on being nudged are crucial for the evaluation of the moral appropriateness of nudging, the current study examines consumers' knowledge of and attitudes toward nudging in general and the realm of health behavior. METHODS: In this qualitative investigation in-depth semi-structured interviews with UK consumers were conducted to examine consumers' attitudes to four domains of inquiry around which the scholarly discussions about nudging have revolved: consumers' approval of nudging, consumers' views on the origin of nudges, consumers' perceived effectiveness of nudging, and consumers' concerns about manipulative aspects of nudging. RESULTS: Interviews revealed that consumers are largely unfamiliar with the concept of nudging altogether. Once defined and explained to them most consumers approve of the concept, especially in the realm of health behavior, given particular conditions: 1. Nudges should be designed for benefiting individuals and society; 2. consumers comprehend the decision-making context and the reasoning behind the promotion of the targeted behavior. Interviews revealed very limited concerns with manipulative aspects of nudges. CONCLUSIONS: These findings call for better information-management to ensure consumers knowledge of nudges and awareness of their current implementation. Under that condition the findings encourage the implementation of nudges benefitting individuals and society in domains that consumers comprehend, such as health behaviors. Further research is required to clarify consumers' concerns and requirements for nudges in more complex domains such as financial decisions and retirement plans.

Put a limit on it: The protective effects of scarcity heuristics when self-control is low.

Low self-control is a state in which consumers are assumed to be vulnerable to making impulsive choices that hurt long-term goals. Rather than increasing self-control, the current research exploits the tendency for heuristic-based thinking in low self-control by employing scarcity heuristics to promote better consumption choices. Results indicate that consumers low in self-control especially benefited and selected more healthy choices when marketed as "scarce" (Study 1), and that a demand (vs supply) scarcity heuristic was most effective in promoting utilitarian products (Study 2) suggests low self-control involves both an enhanced reward orientation and increased tendency to conform to descriptive norms.

Why are people with high self-control happier? The effect of trait self-control on happiness as mediated by regulatory focus.

BACKGROUND: While self-control has often been related to positive outcomes in life such as higher academic achievements and better health, recent insights reveal that people with high trait self-control (TSC) may even experience greater life satisfaction or happiness. OBJECTIVE: The current study further scrutinizes this potential association between TSC and happiness, and examines how regulatory focus, defined as the way people frame and direct their goal pursuit strategies, plays a role in this relationship. Accordingly, the present study examines the mediating role of regulatory-focus (promotion and prevention focus) on the relationship between TSC and happiness. METHOD: Data was collected from 545 individuals (65.9% female, M age = 27.52 years) regarding their TSC, regulatory focus, and happiness. RESULTS: Mediation analyses demonstrate that TSC positively predicts happiness, while this effect was partially mediated by relatively more promotion focus and less prevention focus. CONCLUSION: RESULTS suggest that people with higher TSC are happier possibly because they are: (1) more promotion-focused on acquiring positive gains thereby facilitating more approach-oriented behaviors, and (2) less prevention-focused on avoiding losses thereby reducing avoidance-oriented behaviors. These findings are relevant for topical scientific debates regarding the underlying mechanisms of self-control regarding initiatory and inhibitory behaviors.

The Effect of Stress-Induced Senescence on Aging Human Cord Blood-Derived Endothelial Cells.

PURPOSE: We sought to determine the effect of stress-induced senescence on the permeability to albumin of aging endothelial progenitor cells. METHODS: Human umbilical cord blood derived endothelial cells (hCB-ECs) and human aortic endothelial cells (HAECs) were treated with 200 µM H2O2 and permeability to FITC-bovine serum albumin was measured. Some samples were subsequently treated with 100µM 8-pCPT-2'-O-Me-cAMP, a cAMP analog that activates the Epac1-Rap1 pathway. Cell proliferation was measured with the EdU assay. Phase contrast, and immunofluorescence images were taken to observe morphological changes in cells after exposure to H2O2. RESULTS: hCB-ECs exposed to H2O2 exhibited a significant increase in permeability, but their response differed from the HAECs. Low passage hCB-ECs had a permeability increase of about 82% (p<0.01) compared to aged cells which had a permeability increase of about 37% (p<0.05). This increase in permeability was reduced by treating the cells with 100 µM 8-pCPT-2'-O-Me-cAMP. The younger cells exhibited a significant decrease in proliferation after being subjected to various concentrations of H2O2 whereas the aged cells exhibited a more gradual decrease in the percent of cells in S-phase. These changes also correlated with changes in cell morphology and junction staining. When placed back in the original media, the morphology and permeability of the hCB-ECs returned to the control condition, while the HAECs did not. CONCLUSIONS: The permeability of low and high passage hCB-ECs and HAECs initially increases in response to oxidative stress. hCB-ECs, but not HAECs, were able to recover from the stress 24 hours later. Early passage hCB-ECs were more susceptible to exogenous H2O2 than late passage hCB-ECs. The increase in permeability of hCB-ECs to H2O2 also correlated with decreased cell proliferation and changes in cell junctions.

Effect of walkway length and turning direction on the distance covered in the 6-minute walk test among adults over 50 years of age: a cross-sectional study.

OBJECTIVE: To examine the effect of walkway length and turning direction on the distance covered in the 6-minute walk test (6MWT) in healthy adults aged ≥50 years. DESIGN: Cross-sectional study. SETTING: University-based rehabilitation centre. PARTICIPANTS: Twenty-five healthy adults aged ≥50 years. OUTCOME MEASURES: Distance covered in the 6MWT (6MWD) was recorded in metres. Number of turns during the test using walkways of various lengths (10, 20 and 30m) and different turning directions (turning towards dorminant and non-dorminant side), rate of perceived exertion and heart rate were recorded before and after the test. RESULTS: The 6MWD and the number of turns differed significantly with walkway length (P<0.05). The greatest 6MWD and the lowest number of turns were recorded in the 30-m walkway. Significant increases in heart rate and rate of perceived exertion (P<0.05) were found between the pre-test and post-test for all testing conditions. No significant difference was found between the two turning directions for any distance covered. CONCLUSION: The length of the walkway had a significant effect on the 6MWD, but the turning direction did not. This suggests that subjects can turn in either direction without significantly affecting the results when using a standard walkway in the 6MWT.

Effect of cellular senescence on the albumin permeability of blood-derived endothelial cells.

In this study, we tested the hypotheses that endothelial cells (ECs) derived from human umbilical cord blood (hCB-ECs) exhibit low permeability, which increases as hCB-ECs age and undergo senescence, and that the change in the permeability of hCB-ECs is due to changes in tight junction protein localization and the activity of exchange protein activated by cAMP (Epac)1. Albumin permeability across low-passage hCB-EC monolayers on Transwell membranes was 10 times lower than for human aortic ECs (HAECs) (P < 0.01) but similar to in vivo values in arteries. Expression of the tight junction protein occludin and tyrosine phosphorylation of occludin were less in hCB-ECs than in HAECs (P < 0.05). More hCB-ECs than HAECs underwent mitosis (P < 0.01). hCB-ECs that underwent >44 population doublings since isolation had a significantly higher permeability than hCB-ECs that underwent <31 population doublings (P < 0.05). This age-related increase in hCB-EC permeability was associated with an increase in tyrosine phosphorylation of occludin (P < 0.01); permeability and occludin phosphorylation were reduced by treatment with 2 µM resveratrol. Tyrosine phosphorylation of occludin and cell age influence the permeability of hCB-ECs, whereas levels of EC proliferation and expression of tight junction proteins did not explain the differences between hCB-EC and HAEC permeability. The elevated permeability in late passage hCB-ECs was reduced by 25-40% by elevation of membrane-associated cAMP and activation of the Epac1 pathway. Given the similarity to in vivo permeability to albumin and the high proliferation potential, hCB-ECs may be a suitable in vitro model to study transport-related pathologies and cell aging.

Three dimensional assessment of the pharyngeal airway in individuals with non-syndromic cleft lip and palate.

INTRODUCTION: Children with cleft lip and palate (CLP) are known to have airway problems. Previous studies have shown that individuals with CLP have a 30% reduction in nasal airway size compared to non-cleft controls. No reports have been found on cross-sectional area and volume of the pharyngeal airway in clefts. Introduction of Cone-Beam CT (CBCT) and imaging software has facilitated generation of 3D images for assessment of the cross-sectional area and volume of the airway. OBJECTIVE: To assess the pharyngeal airway in individuals with CLP using CBCT by measuring volume and smallest cross-sectional areas and compare with 19 age- and sex-matched non-cleft controls. METHODS: Retrospective study of CBCT data of pre-adolescent individuals (N = 19, Mean age = 10.6, 7 females, 12 males, UCLP = 6, BCLP = 3) from the Center for Craniofacial Anomalies. Volumetric analysis was performed using image segmentation features in CB Works 3.0. Volume and smallest cross-sectional were studied in both groups. Seven measurements were repeated to verify reliability using Pearson correlation coefficient. Volume and cross-sectional area differences were analyzed using paired t-tests. RESULTS: The method was found to be reliable. Individuals with CLP did not exhibit smaller total airway volume and cross sectional area than non-CLP controls. CONCLUSION: 3D imaging using CBCT and CB Works is reliable for assessing airway volume. Previous studies have shown that the nasal airway is restricted in individuals with CLP. In our study, we found that the pharyngeal airway is not compromised in these individuals.

Walkway length, but not turning direction, determines the six-minute walk test distance in individuals with stroke.

OBJECTIVES: To examine (1) the effect of different walkway distances, and (2) turning directions on the six-minute walk test (6MWT) in subjects with stroke. DESIGN: A cross-sectional study. SETTING: University-based rehabilitation center. PARTICIPANTS: Subjects (N=26) with chronic stroke. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Total distance covered and number of turns in the 6MWT with different walkway lengths (10-, 20-, and 30-m walkway distances) and turning directions (turning to affected side and unaffected side); rate of perceived exertion (RPE) using Borg Scale, and heart rate (HR) using handheld pulse oximeter recorded before and immediately after the test. RESULTS: The distance covered and the number of turns in the 6MWT were significantly different between different walkway lengths (P<.05), with the longest distance covered and lowest number of turns in the 30-m walkway distance. For all walkway lengths, turning to the affected or unaffected side did not result in significant differences in the distance covered and the number of turns in the 6MWT. Significant increases were found between the pretest and posttest for the HR and RPE (P<.05) in all testing conditions. There was no significant effect of walkway distance and turning direction on the change in HR and RPE between the 6 conditions of the 6MWT. CONCLUSIONS: Different walkway distances have a significant effect on the distance covered in the 6MWT, whereas turning direction did not significantly affect the distance covered in the 6MWT.