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This paper reports the molecular organization and mechanical properties of electrospun, post-drawn polyacrylonitrile (PAN) nanofibers. Without post-drawing, the polymer chain was kinked and oriented in hexagonal crystalline structures. Immediate post-drawing in the semi-solid state disrupted the crystal structures and chain kink at maximum draw ratio. Structural re-orientation at maximum draw resulted in a 500% increase in Young's modulus and a 100% increase in ultimate tensile strength. By applying post-drawing to electrospinning it may be possible to obtain PAN fibers and PAN-derived carbon fibers with enhanced mechanical properties compared to available fabrication technologies.
Innovation Concept: High-quality cardiopulmonary resuscitation saves lives; however, current certification standards can leave providers poorly prepared to perform effective chest compressions (CCs). We designed a training program based on the emerging model of skill maintenance through frequent short practice sessions. The ideal frequency of training is currently unknown. Our goal was to provide medical students with access to efficient and effective CC training and to determine an optimal training interval. Methods: Thirty-six second-year medical students were randomized to three groups that trained at different frequencies: once every two months (q2m) (n = 12), once every four months (q4m) (n = 13), and control (n = 11). Study duration was eight months with the intervention groups, q2m and q4m, participating in five and three sessions respectively. The control group was assessed at study start and end, receiving no training in between. At each session, participants completed a one-minute pre-test of CC performance, viewed a one-minute training video, practiced CCs for two minutes with real-time feedback, and completed a one-minute post-test. Performance parameters measured were CC depth, rate, release, and hand positioning. A final “compression score” assessed integrated performance across these parameters and served as our primary outcome. Participants also reported pre- and post-training comfort with performing CCs which served as our secondary outcome. Curriculum, Tool or Material: Our “Quick Refresher Sessions” (QRS) were completed by participants independently without requiring an assessor or facilitator. A manikin with the ability to record and provide real-time quantitative feedback on CC quality was connected to a laptop running a customized interface. Participants typed in an individualized code and were guided through their six-minute sessions automatically. Conclusion: Immediately following the first training session, subjects had significant improvement in compression score (p < 0.001) and skill comfort (p < 0.001). At eight months, both intervention groups, q2m and q4m, achieved higher compression scores than control (p = 0.001 and p = 0.011) and showed greater increase in comfort level (p = 0.002 and p = 0.010). Performance between intervention groups at eight months was not statistically different. Overall, we conclude that independent QRS training every two or four months led to improved CC quality and provider comfort. Future directions include increasing sample size and tailoring training intervals to individual performance.
Introduction: Point-of-Care Ultrasound (PoCUS) is being increasingly utilized during cardiac arrests for prognosis. Following the publication of recent studies, the goal of this study was to systematically review and analyze the literature to evaluate the accuracy of PoCUS in predicting return of spontaneous circulation (ROSC), survival to hospital admission (SHA), and survival to hospital discharge (SHD) in adult patients with non-traumatic, non- shockable out- of-hospital or emergency department cardiac arrest. Methods: A systematic review and meta-analysis was completed. A search of Medline, EMBASE, Cochrane, CINAHL, ClinicalTrials.gov and the World Health Organization Registry was completed from 1974 until August 24th 2018. Adult randomized controlled trials and observational studies were included. The QUADAS-2 tool was applied by two independent reviewers. Data analysis was completed according to PRISMA guidelines and with a random effects model for the meta-analysis. Heterogeneity was assessed using I-squared statistics. Results: Ten studies (1,485 participants) were included. Cardiac activity on PoCUS had a pooled sensitivity of 59.9% (95% confidence interval 36.5%-79.4%) and specificity of 91.5% (80.8%-96.5%) for ROSC; 74.7% (58.3%-86.2%) and 80.5% (71.7%-87.4%) for SHA; and 69.4% (45.5%-86.0%) and 74.6% (59.8%-85.3%) for SHD. The sensitivity of cardiac activity on PoCUS for predicting ROSC was 24.7%(6.8%-59.4%) in the asystole subgroup compared with 77% (59.4%-88.5%) within the PEA subgroup. Cardiac activity on PoCUS, compared to an absence had an odd ratio of 15.9 (5.9-42.5) for ROSC, 9.8 (4.9-19.4) for SHA and 5.7 (2.1-15.6) for SHD. Positive likelihood ratio (LR) was 6.65 (3.16-14.0) and negative LR was 0.27 (0.12-0.61) for ROSC. Conclusion: Cardiac activity on PoCUS was associated with improved odds for ROSC, SHA, and SHD among adults with non-traumatic asystole and PEA. We report lower sensitivity and higher negative likelihood ratio, but with greater heterogeneity compared to previous systematic reviews. PoCUS may provide valuable information in the management of non-traumatic PEA or asystole, but should not be viewed as the sole predictor in determining outcomes in these patients.
Dietary assessment methods including FFQ and food diaries are associated with many measurement errors including energy under-reporting and incorrect estimation of portion sizes. Such errors can lead to inconsistent results especially when investigating the relationship between food intake and disease causation. To improve the classification of a person's dietary intake and therefore clarify proposed links between diet and disease, reliable and accurate dietary assessment methods are essential. Dietary biomarkers have emerged as a complementary approach to the traditional methods, and in recent years, metabolomics has developed as a key technology for the identification of new dietary biomarkers. The objective of this review is to give an overview of the approaches used for the identification of biomarkers and potential use of the biomarkers. Over the years, a number of strategies have emerged for the discovery of dietary biomarkers including acute and medium term interventions and cross-sectional/cohort study approaches. Examples of the different approaches will be presented. Concomitant with the focus on single biomarkers of specific foods, there is an interest in the development of biomarker signatures for the identification of dietary patterns. In the present review, we present an overview of the techniques used in food intake biomarker discover, including the experimental approaches used and challenges faced in the field. While significant progress has been achieved in the field of dietary biomarkers in recent years, a number of challenges remain. Addressing these challenges will be key to ensure success in implementing use of dietary biomarkers.
Introduction: High quality Cardiopulmonary Resuscitation (CPR) saves lives, however skill retention after standard Basic Life support (BLS) courses has been shown to be poor. Our goal was to develop a student-run, mentorship based program to allow repetitive practice of BLS skills while minimizing resource commitment and time requirements. Methods: We developed a top down training program that relied on online teaching resources, regular simulation training and near-peer feedback. First year medical students were given the opportunity to participate in the program and baseline CPR quality was documented. They were then divided into intervention and control groups. The intervention group participated in bi-monthly 40-minute small group training sessions directed by senior medical students and monitored by a staff physician. The control group received no further training. At the end of the 8-month study period CPR quality was documented for all participants. Results: We included data from 54 medical students. Overall compression depth and rate were monitored using Laderall SimMan 3G(TM) high-fidelity CPR mannequins. Average rate and depth of compression were significantly improved in the intervention group relative to both the control group that did not receive training, as well as relative to the intervention groups own pre intervention values (both with p values below 0.05 using Mann-Whitney tests and an intention to treat analysis for loss to follow up). Conclusion: Our study demonstrated a significant improvement in CPR quality as a result of our intervention. Survey data also indicated positive feedback from participants in relation to comfort with in-hospital CPR. As such we intend to continue to run this program, identifying participants each year whom can move into training and leadership roles to help foster CPR and basic resuscitation in our medical community.
FFQ, food diaries and 24 h recall methods represent the most commonly used dietary assessment tools in human studies on nutrition and health, but food intake biomarkers are assumed to provide a more objective reflection of intake. Unfortunately, very few of these biomarkers are sufficiently validated. This review provides an overview of food intake biomarker research and highlights present research efforts of the Joint Programming Initiative ‘A Healthy Diet for a Healthy Life’ (JPI-HDHL) Food Biomarkers Alliance (FoodBAll). In order to identify novel food intake biomarkers, the focus is on new food metabolomics techniques that allow the quantification of up to thousands of metabolites simultaneously, which may be applied in intervention and observational studies. As biomarkers are often influenced by various other factors than the food under investigation, FoodBAll developed a food intake biomarker quality and validity score aiming to assist the systematic evaluation of novel biomarkers. Moreover, to evaluate the applicability of nutritional biomarkers, studies are presently also focusing on associations between food intake biomarkers and diet-related disease risk. In order to be successful in these metabolomics studies, knowledge about available electronic metabolomics resources is necessary and further developments of these resources are essential. Ultimately, present efforts in this research area aim to advance quality control of traditional dietary assessment methods, advance compliance evaluation in nutritional intervention studies, and increase the significance of observational studies by investigating associations between nutrition and health.
Research shows that cognitive rehabilitation (CR) has the potential to improve goal performance and enhance well-being for people with early stage Alzheimer’s disease (AD). This single subject, multiple baseline design (MBD) research investigated the clinical efficacy of an 8-week individualised CR intervention for individuals with early stage AD.
Three participants with early stage AD were recruited to take part in the study. The intervention consisted of eight sessions of 60–90 minutes of CR. Outcomes included goal performance and satisfaction, quality of life, cognitive and everyday functioning, mood, and memory self-efficacy for participants with AD; and carer burden, general mental health, quality of life, and mood of carers.
Visual analysis of MBD data demonstrated a functional relationship between CR and improvements in participants’ goal performance. Subjective ratings of goal performance and satisfaction increased from baseline to post-test for three participants and were maintained at follow-up for two. Baseline to post-test quality of life scores improved for three participants, whereas cognitive function and memory self-efficacy scores improved for two.
Our findings demonstrate that CR can improve goal performance, and is a socially acceptable intervention that can be implemented by practitioners with assistance from carers between sessions. This study represents one of the promising first step towards filling a practice gap in this area. Further research and randomised-controlled trials are required.
This study explored how coping with war-related traumatic events in Sierra Leone impacted mental health outcomes among 529 youth (aged 10–17 at baseline; 25% female) using longitudinal data from three time points (Time 1 in 2002, Time 2 in 2004, and Time 3 in 2008). We examined two types of coping items (approach and avoidance); used multiple regression models to test their relations with long-term mental health outcomes (internalizing behaviors, externalizing behaviors, adaptive/prosocial behaviors, and posttraumatic stress symptoms); and used mediation analyses to test whether coping explained the relation between previous war exposures (being raped, death of parent(s), or killing/injuring someone during the war) and those outcomes. We found that avoidance coping items were associated with lower internalizing and posttraumatic stress behaviors at Time 3, and provided some evidence of mediating the relation between death of parent(s) during the war and the two outcomes mentioned above. Approach coping was associated with higher Time 3 adaptive/prosocial behaviors, whereas avoidance coping was associated with lower Time 3 adaptive/prosocial behaviors. Avoidance coping may be a protective factor against mental illness, whereas approach coping may be a promotive factor for adaptive/prosocial behaviors in war-affected societies. This study has important implications for designing and implementing mental health interventions for youth in postconflict settings.
Mealtime interventions typically focus on institutionalised older adults, but we wanted to investigate whether they may also be effective among those living independently. Using a randomised controlled trial design, we assessed the effects of a novel mealtime intervention on self-efficacy, food enjoyment and energy intake. A total of 100 adults living alone aged over 60 years were randomised to the treatment or control conditions: all received a guidebook on nutrition and culinary skills. Treatment group participants received a weekly visit from a trained volunteer who prepared and shared a meal with them. Participants in the treatment group showed improvements relative to those in the control group at borderline significance (P=0·054) for self-efficacy and at significance for food enjoyment. Significant improvements were observed in female participants in the treatment but not in the control group in energy intake (although following corrections for multiple comparisons, only the effect on food enjoyment remained significant). These findings will inform the design of future complex interventions. For this type of intervention to be successful, more focus has to be placed on making interventions more personalised, potentially according to sex. Findings are important for nutritional sciences as they indicate that, in order to improve energy intake and food enjoyment among older adults, multimodal nutritional interventions including social components may be successful.
In recent times many western governments have either considered or actually applied some form of price regulation in order to combat an accelerating world wide inflation that has respected no one’s national boundaries. The price controls that were applied by governments pressured to take action have been typically collections of pragmatic administrative procedures, requiring the creation of their own operating bureaucracies. Often neither the original arguments that were raised in favor nor the resulting measures enacted were seen by economists as grounded in any coherent piece of orthodox economic theory. There has been many theoretical articles written about these aspects of price regulation, however, empirical studies attempting to discover the consequences of these systems at the level of the individual decision-makers involved have been few due to the unavailability of relevant data. This recent Belgian experience then offers a unique opportunity as a large volume of material has been made available for econometric study.
The current study investigated use of a controlled misting environment to simulate field conditions that have been implicated in high levels of the malting barley defect, grain skinning. More than 200 spring barley varieties were assessed to identify those varieties that were particularly resistant or susceptible to the defect. Relationships between skinning severity and the traits ear length, floret number, grain number and grain weight were examined among the varieties. In a panel of seven varieties chosen as treatment controls, misting was found to significantly increase skinning severity. The misting treatment had no effect on measured ear traits of these varieties. Among the 200 varieties grown under the misting treatment, there was a continuous spectrum of skinning severities, which were not correlated with ear length, floret number, grain number or grain weight. Using the misting treatment, differences in susceptibility to grain skinning could be determined among varieties. As the misting treatment did not affect measured ear traits, and no correlation was found between ear traits and skinning severity among varieties, the effect of misting on skinning severity must be mediated through other physiological characteristics.
The goal of preterm nutrition in achieving growth and body composition approximating that of the fetus of the same postmenstrual age is difficult to achieve. Current nutrition recommendations depend largely on expert opinion, due to lack of evidence, and are primarily birth weight based, with no consideration given to gestational age and/or need for catch-up growth. Assessment of growth is based predominately on anthropometry, which gives insufficient attention to the quality of growth. The present paper provides a review of the current literature on the nutritional management and assessment of growth in preterm infants. It explores several approaches that may be required to optimise nutrient intakes in preterm infants, such as personalising nutritional support, collection of nutrient intake data in real-time, and measurement of body composition. In clinical practice, the response to inappropriate nutrient intakes is delayed as the effects of under- or overnutrition are not immediate, and there is limited nutritional feedback at the cot-side. The accurate and non-invasive measurement of infant body composition, assessed by means of air displacement plethysmography, has been shown to be useful in assessing quality of growth. The development and implementation of personalised, responsive nutritional management of preterm infants, utilising real-time nutrient intake data collection, with ongoing nutritional assessments that include measurement of body composition is required to help meet the individual needs of preterm infants.
Peer volunteers can be key to delivering effective social cognitive interventions due to increased potential for social modeling. We consulted peer volunteers who had just taken part in an 8-week social and nutritional mealtime intervention with older adults living alone, to seek their evaluation of the intervention.
Semi-structured focus groups were used with a total of 21 volunteers (17 female) and two facilitators. Thematic analysis was used to interrogate the data.
Six themes (16 sub-themes) are discussed. Peer volunteers described the importance of the socializing aspect of the intervention, of pairing considerations and compatibility in peer interventions, of considering the needs of the participant, of benefits to the volunteers, and of the practical considerations of conducting an intervention. Volunteers also discussed considerations for future research and services for older adults living alone.
Volunteers found their involvement in the intervention to be personally beneficial, and revealed some valuable considerations for the researchers to take forward to future research. Results are pertinent to intervention design and could inform future social cognitive and other peer-oriented interventions for older adults living alone.
The 2010 American Heart Association Guidelines stress the importance of high quality cardiopulmonary resuscitation (CPR) as a predictor of survival from cardiac arrest. However, resuscitation training is often facilitated and evaluated by instructors without access to objective measures of CPR quality. This study aims to determine whether instructors experienced in the area of adult resuscitation (emergency department staff and senior residents) can accurately assess the quality of chest compressions as a component of their global assessment of a simulated resuscitation scenario.
This is a prospective observational study in which objective chest compression quality data (rate, depth, and fraction) were collected from the simulation manikin and compared to subjective instructor assessment. Data were collected during weekly simulation training sessions for residents, medical students, and nursing students.
We included data from 24 simulated resuscitation scenarios assessed by 1 of 15 instructors. Subjective assessment of chest compression quality identified an adequate compression rate (100–120 compressions per minute) with a sensitivity of 0.17 (confidence interval [CI] 0.02–0.32) and specificity of 0.06 (CI −0.04–0.15), adequate depth (>50 mm) with a sensitivity of 0 and specificity of 0.38 (CI 0.18–0.57), and adequate fraction (>80%) with a sensitivity of 1 and a specificity of 0.25 (CI 0.08–0.42).
Instructor assessment of chest compression rate, depth, and fraction demonstrates poor sensitivity and specificity when compared to the data from the simulation manikin. These results support the use of objective and technologically supported measures of chest compression quality for feedback during resuscitation education using simulators.
Several studies suggest that neighborhood deprivation is a unique risk factor in child and adolescent development of problem behavior. We sought to examine whether previously established intervention effects of the Family Check-Up (FCU) on child conduct problems at age 7.5 would persist through age 9.5, and whether neighborhood deprivation would moderate these effects. In addition, we examined whether improvements in parent–child interaction during early childhood associated with the FCU would be related to later reductions in child aggression among families living in the highest risk neighborhoods. Using a multisite cohort of at-risk children identified on the basis of family, child, and socioeconomic risk and randomly assigned to the FCU, intervention effects were found to be moderated by neighborhood deprivation, such that they were only directly present for those living at moderate versus extreme levels of neighborhood deprivation. In addition, improvements in child aggression were evident for children living in extreme neighborhood deprivation when parents improved the quality of their parent–child interaction during the toddler period (i.e., moderated mediation). Implications of the findings are discussed in relation to the possibilities and possible limitations in prevention of early problem behavior for those children living in extreme and moderate levels of poverty.