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Automated manufacturing of thermoplastic composites has found increased interest in aerospace applications over the past three decades because of its great potential in low-cost, high rate, repeatable production of high performance composite structures. Experimental validation is a key element in the development of structures made using this emerging technology. In this work, a
mm variable-stiffness unitised integrated-stiffener out-of-autoclave thermoplastic composite wingbox is tested for a combined shear-bending-torsion induced buckling load. The wingbox is manufactured by in-situ consolidation using a laser-assisted automated tape placement technique. It is made and tested as a demonstrator section located at 85% of the wing semi-span of a B-737/A320 sized aircraft. A bespoke in-house test rig and two aluminium dummy wingboxes are also designed and manufactured for testing the wingbox assembly which spans more than 3m. Prior to testing, the wingbox assembly and the test rig were analysed using a high fidelity finite element method to minimise the failure risk due to the applied load case. The experimental test results of the wingbox are also compared with the predictions made by a numerical study performed by nonlinear finite element analysis showing less than 5% difference in load-displacement behaviour and buckling load and full agreement in predicting the buckling mode shape.
This study examined the long-term effects of a randomized controlled trial of the Family Check-Up (FCU) intervention initiated at age 2 on inhibitory control in middle childhood and adolescent internalizing and externalizing problems. We hypothesized that the FCU would promote higher inhibitory control in middle childhood relative to the control group, which in turn would be associated with lower internalizing and externalizing symptomology at age 14. Participants were 731 families, with half (n = 367) of the families assigned to the FCU intervention. Using an intent-to-treat design, results indicate that the FCU intervention was indirectly associated with both lower internalizing and externalizing symptoms at age 14 via its effect on increased inhibitory control in middle childhood (i.e., ages 8.5–10.5). Findings highlight the potential for interventions initiated in toddlerhood to have long-term impacts on self-regulation processes, which can further reduce the risk for behavioral and emotional difficulties in adolescence.
Failing to communicate a message in everyday settings can be a frustrating experience. However, miscommunication can lead to disaster in high-stakes situations. Yet in these contexts, under pressure to perform efficiently, speakers may also find themselves with limited resources to devote to message clarity. To understand how cognitive constraint affects communication and explore a possible low-cost solution, we investigated a method for moderating ambiguity production in the face of competing attentional demands: taking the perspective of the listener. Over two experiments, speakers labeled images (Experiment 1) or provided instructions (Experiment 2) to listeners in a non-interactive communication task. In both experiments, speakers were randomly assigned to cognitive constraint and perspective-taking conditions, such that some speakers were under higher cognitive constraint and some speakers received a simple perspective-taking directive. We replicated previous findings that additional cognitive constraint impairs speakers’ ability to avoid ambiguity. Additionally, we found that a simple directive can promote speaker clarity when labeling images, but not when providing instructions. These results suggest that a simple directive is likely insufficient to ensure speaker clarity in all cases.
This study investigates suicide risk in late childhood and early adolescence in relation to a family-centered intervention, the Family Check-Up, for problem behavior delivered in early childhood. At age 2, 731 low-income families receiving nutritional services from Women, Infants, and Children programs were randomized to the Family Check-Up intervention or to a control group. Trend-level main effects were observed on endorsement of suicide risk by parents or teachers from ages 7.5 to 14, with higher rates of suicide risk endorsement in youth in the control versus intervention condition. A significant indirect effect of intervention was also observed, with treatment-related improvements in inhibitory control across childhood predicting reductions in suicide-related risk both at age 10.5, assessed via diagnostic interviews with parents and youth, and at age 14, assessed via parent and teacher reports. Results add to the emerging body of work demonstrating long-term reductions in suicide risk related to family-focused preventive interventions, and highlight improvements in youth self-regulatory skills as an important mechanism of such reductions in risk.
Animal disease outbreaks can cause disruptions in domestic and international markets. Business continuity aims to provide a proactive approach to alleviate some of these negative effects on consumers, producers, and agribusinesses. Using a partial equilibrium model of the U.S. egg industry, the economic impacts of business continuity during an epidemiological simulated disease event are modeled. Results show total welfare losses can be reduced by allowing permitted movement during an outbreak given a specified level of biosecurity. Understanding the potential market responses business continuity can have on the market may lead to reductions in the negative implications of a disease event.
This study examined the effectiveness of a formal postdoctoral education program designed to teach skills in clinical and translational science, using scholar publication rates as a measure of research productivity.
Participants included 70 clinical fellows who were admitted to a master’s or certificate training program in clinical and translational science from 1999 to 2015 and 70 matched control peers. The primary outcomes were the number of publications 5 years post-fellowship matriculation and time to publishing 15 peer-reviewed manuscripts post-matriculation.
Clinical and translational science program graduates published significantly more peer-reviewed manuscripts at 5 years post-matriculation (median 8 vs 5, p=0.041) and had a faster time to publication of 15 peer-reviewed manuscripts (matched hazard ratio = 2.91, p=0.002). Additionally, program graduates’ publications yielded a significantly higher average H-index (11 vs. 7, p=0.013).
These findings support the effectiveness of formal training programs in clinical and translational science by increasing academic productivity.
OBJECTIVES/SPECIFIC AIMS: A key factor for success in science is the ability to communicate clearly and succinctly using language appropriate to the audience. Most predoctoral training programs offer opportunities for students to build oral and written communication skills at local and national conferences. However, this rarely provides specific feedback and tends to be episodic. The Mayo Clinic Center for Clinical and Translational Science (CCaTS) has developed an environment for deliberate practice of presentation skills within a weekly Works in Progress and Journal Club session using a learning management system, Blackboard Collaborate. The learning management system captures the presentation that can then be viewed by the student. Watching yourself give a presentation is a powerful learning tool. The learning objectives of the sessions provide students deliberate practice to: (1) Build critical presentation skills for a 1-minute elevator talk, a 2-minute poster overview, a 10-minute oral presentation of your science to a science audience and to a non-science audience. (2) Develop constructive reviewer skills by completing peer reviews of presentations. (3) Develop critical thinking skills to ask thought provoking questions during presentations. By utilizing a curriculum that offers video-recording for reflection and self-evaluation, Mayo Clinic CCaTS has developed an environment in which predoctoral students are encouraged and supported to constantly hone their presentation skills. METHODS/STUDY POPULATION: All CCaTS predoctoral students are asked to prepare presentations in several formats for the weekly 1-hour session. The students’ presentations of their science or journal articles are recorded and saved within Blackboard; a link is provided for the student to review personally, with a mentor, and with the Education Coordinator to discuss the strengths and weaknesses of the presentation. During each session, faculty facilitators encourage students to ask thought provoking questions, and student reviewers are assigned to provide critical and constructive written feedback to the presenter. Sessions providing tools and guidelines for constructive feedback and developing critical and constructive questions are regularly interspersed. RESULTS/ANTICIPATED RESULTS: By reviewing a video recording of their presentations, CCaTS predoctoral students get the opportunity to self-evaluate their performance as an audience member. By going through this process of preparing, presenting, reflecting on their presentations, and discussing their strengths and weaknesses with mentors and classmates, the students gain both powerful presentation skills and methods to improve their delivery and reviewer skills. DISCUSSION/SIGNIFICANCE OF IMPACT: Successful scientists, whether in academia or industry, have the ability to communicate their science clearly using appropriate and common language specific to each audience they present to. By utilizing a curriculum that offers video-recording for reflection and self-evaluation, Mayo Clinic CCaTS has developed an environment in which predoctoral students are encouraged and supported to constantly hone their presentation skills.
To determine the impact of recurrent Clostridium difficile infection (RCDI) on patient behaviors following illness.
Using a computer algorithm, we searched the electronic medical records of 7 Chicago-area hospitals to identify patients with RCDI (2 episodes of CDI within 15 to 56 days of each other). RCDI was validated by medical record review. Patients were asked to complete a telephone survey. The survey included questions regarding general health, social isolation, symptom severity, emotional distress, and prevention behaviors.
In total, 119 patients completed the survey (32%). On average, respondents were 57.4 years old (standard deviation, 16.8); 57% were white, and ~50% reported hospitalization for CDI. At the time of their most recent illness, patients rated their diarrhea as high severity (58.5%) and their exhaustion as extreme (30.7%). Respondents indicated that they were very worried about getting sick again (41.5%) and about infecting others (31%). Almost 50% said that they have washed their hands more frequently (47%) and have increased their use of soap and water (45%) since their illness. Some of these patients (22%–32%) reported eating out less, avoiding certain medications and public areas, and increasing probiotic use. Most behavioral changes were unrelated to disease severity.
Having had RCDI appears to increase prevention-related behaviors in some patients. While some behaviors are appropriate (eg, handwashing), others are not supported by evidence of decreased risk and may negatively impact patient quality of life. Providers should discuss appropriate prevention behaviors with their patients and should clarify that other behaviors (eg, eating out less) will not affect their risk of future illness.
Climatic fluctuation is often cited as a major factor in the collapse of Maya civilisation during the Terminal Classic Period (e.g. Luzzadder-Beach et al.2016). Evidence of how people dealt or failed to deal with it has only recently become a more widespread focus for archaeologists. Investigations at Xcoch in the Puuc Hills show the various ways in which resident populations sought to manage water stores when faced with a climate prone to drought and other meteorological extremes. The study also presents results from the analysis of nearby speleothem laminae, which indicate that severe episodes of flooding and droughts may have contributed to a collapse in the population around AD 850.
We present an age-structured mathematical model of malaria and pneumonia to study the effect of two capacity-building interventions: Integrated Management of Infectious Diseases (IMID) and On-site Support Services (OSS). IMID leads to a reduction in malaria prevalence by more than 2·4% across the [0,5), [5,14) and [14,50) age groups. IMID + OSS reduces it by more than 16·0% across all age groups. IMID decreases pneumonia prevalence by more than 3·0% across all age groups while IMID + OSS decreases it by more than 1·0% across all age groups. The number of malaria and pneumonia deaths is reduced by 7·8% by IMID across all age groups and IMID + OSS decreases this number by 30·5% across all age groups, which translates to saving a life of a child per month. Prevalence of malaria-pneumonia for the [0,5) age group is 0·52% at baseline, and IMID and IMID + OSS reduce it by 6·6% and 23·6%, respectively. There is no change in incidence of malaria or pneumonia disease episodes. The results also indicate that triaging of children contributes more than 50% to the effect of the interventions in reduction of deaths and a range of 14–91% in reduction of disease cases.
Surfactant is a unique lipid and protein substance made by type II cells in the lung that provides inflation stability, decreases the work of breathing, and has components with innate host defense properties. Surfactant is normally synthesized and secreted into the airspaces of the fetal lung as term approaches, but it can be induced earlier in gestation by fetal exposures to corticosteroids or inflammation. The surfactant deficiency associated with preterm birth can cause severe respiratory failure termed respiratory distress syndrome (RDS), a frequently lethal disease before the availability of clinical surfactants to treat infants. Surfactant components each have complex metabolic characteristics in the premature and mature lung. Term infants can have severe surfactant dysfunction because of rare mutations that disrupt surfactant protein synthesis or processing. The research resulting in the understanding of surfactant metabolism and function and subsequent treatment of RDS is a highlight of progress from science to cure strategies in pulmonary medicine.
The imperfection sensitivity of cylindrical panels under compression loading is shown to be not only reduced but effectively eliminated using stiffness tailoring techniques. Shells are designed with variable angle-tow (VAT) laminae, giving their laminates variable-stiffness properties over the surface co-ordinates. By employing an asymptotic model of the non-linear shell behaviour and a genetic algorithm, the post-buckling stability was maximised with respect to the VAT design variables. Results for optimised straight-fibre and VAT shells are presented in comparison with quasi-isotropic designs. In the straight-fibre case, small improvements in the post-buckling stability are shown to be possible but at the expense of the buckling load. In the VAT case, on the other hand, considerable improvements in the post-buckling stability are obtained and drops in axial stiffness and load associated with buckling are reduced to negligible levels. The improvements are shown to be a result of a benign membrane stress distribution prior to buckling and a localisation of the buckling mode. The asymptotic results are compared with non-linear finite-element analyses and are found to be in good agreement. Potential future multi-objective optimisation studies are discussed.
Background: There are no disease modifying agents for the treatment of Alzheimer’s disease (AD). Pathologically, AD is associated with the misfolding of two peptides: beta-amyloid (plaques) and tau (tangles). Methods: Using large-scale computer simulations, we modelled the misfolding of both beta-amyloid and tau, identifying a common conformational motif (CCM; i.e. an abnormal peptide shape), present in both beta-amyloid and tau, that promotes their misfolding. We screened a library of 11.8 million compounds against this in silico model of protein misfolding, identifying three novel molecular classes of putative therapeutics as anti-protein misfolding agents. We synthesized approximately 400 new chemical entity drug-like molecules in each of these three classes (i.e. 1200 potential drug candidates). These were comprehensively screened in a battery of five in vitro protein oligomerization assays. Selected compounds were next evaluated in the APP/PS1 doubly transgenic mouse model of AD. Results: Two new classes of molecules were identified with the ability to block the oligomerization of both beta-amyloid and tau. These compounds are drug-like with good pharmacokinetic properties and are brain-penetrant. They exhibit excellent efficacy in transgenic mouse models. Conclusion: Computer aided drug design has enabled the discovery of novel drug-like molecules able to inhibit both tau and beta-amyloid misfolding.
To determine whether implementation of a multifaceted intervention would significantly reduce the incidence of central line–associated bloodstream infections.
Prospective cohort collaborative.
SETTING AND PARTICIPANTS
Intensive care units of the Abu Dhabi Health Services Company hospitals in the Emirate of Abu Dhabi.
A bundled intervention consisting of 3 components was implemented as part of the program. It consisted of a multifaceted approach that targeted clinician use of evidence-based infection prevention recommendations, tools that supported the identification of local barriers to these practices, and implementation ideas to help ensure patients received the practices. Comprehensive unit-based safety teams were created to improve safety culture and teamwork. Finally, the measurement and feedback of monthly infection rate data to safety teams, senior leaders, and staff in participating intensive care units was encouraged. The main outcome measure was the quarterly rate of central line–associated bloodstream infections.
Eighteen intensive care units from 7 hospitals in Abu Dhabi implemented the program and achieved an overall 38% reduction in their central line–associated bloodstream infection rate, adjusted at the hospital and unit level. The number of units with a quarterly central line–associated bloodstream infection rate of less than 1 infection per 1,000 catheter-days increased by almost 40% between the baseline and postintervention periods.
A significant reduction in the global morbidity and mortality associated with central line–associated bloodstream infections is possible across intensive care units in disparate settings using a multifaceted intervention.
Infect. Control Hosp. Epidemiol. 2015;36(7):816–822
Photo-actuating structures inspired by the chemical sensing and signal transmission observed in sun-tracking leaves have recently been proposed by Dicker et al. The proposed light tracking structures are complex, multicomponent material systems, principally composed of a reversible photoacid or base, combined with a pH responsive hydrogel actuator. New modelling and characterization approaches for pH responsive hydrogels are presented in order to facilitate the development of the proposed structures. The model employs Donnan equilibrium for the prediction of hydrogel swelling in systems where the pH change is a variable resulting from the equilibrium interaction of all free and fixed (hydrogel) species. The model allows for the fast analysis of a variety of combinations of material parameters, allowing for the design space for the proposed photo-actuating structures to be quickly established. In addition, experimental examination of the swelling of a polyether-based polyurethane and poly(acrylic acid) interpenetrating network hydrogel is presented. The experiment involves simultaneously performing a titration of the hydrogel, and undertaking digital image correlation (DIC) to determine the hydrogel’s state of swelling. DIC allows for the recording of the hydrogel’s state of swelling with previously unattained levels of resolution. Experimental results provide both model material properties, and a means for model validation.
Since the publication of “A Compendium of Strategies to Prevent Healthcare-Associated Infections in Acute Care Hospitals” in 2008, prevention of healthcare-associated infections (HAIs) has become a national priority. Despite improvements, preventable HAIs continue to occur. The 2014 updates to the Compendium were created to provide acute care hospitals with up-to-date, practical, expert guidance to assist in prioritizing and implementing their HAI prevention efforts. It is the product of a highly collaborative effort led by the Society for Healthcare Epidemiology of America (SHEA), the Infectious Diseases Society of America (IDSA), the American Hospital Association (AHA), the Association for Professionals in Infection Control and Epidemiology (APIC), and The Joint Commission, with major contributions from representatives of a number of organizations and societies with content expertise, including the Centers for Disease Control and Prevention (CDC), the Institute for Healthcare Improvement (IHI), the Pediatric Infectious Diseases Society (PIDS), the Society for Critical Care Medicine (SCCM), the Society for Hospital Medicine (SHM), and the Surgical Infection Society (SIS).