Supporting postgraduate students in their role as clinical teachers: a pilot study

In higher education, reliance on part-time teachers, including postgraduate students (PGs), in our undergraduate (UG) programmes is widespread. Dental education is no exception: the bulk of our UG clinical teaching/supervision is provided by casually-employed clinicians. Consistent with reports highlighting the need for professional development for part-time (including PG) teachers, we identified our PGs needed support. This paper describes the programme we developed for our PGs and the initial evaluation. Recommendations from the literature informed our programme design. Evaluation of the programme involved PG-clinical teachers’ perceptions of their experience and analysis of their learning outcomes, using pre- and post-tests. The tests required PG-clinical teachers to identify behaviours related to UG clinical assessment criteria and clinical teacher attributes, and judge the level of performance portrayed in a series of UG clinic video simulations. To check that clinical assessment criteria for UGs and clinical teacher attributes were identifiable, experienced-clinical teachers completed the same tests. Learning from repeated viewing of the test-videos was not evident. It was difficult to identify and/or classify UG clinical assessment criteria in the videos. Both PG- and experienced-clinical teachers identified and classified more clinical teacher attributes than UG clinical assessment criteria. There was some improvement by PG-clinical teachers in identifying and classifying clinical teacher attributes. These data indicated the programme may have contributed to PG-clinical teachers’ learning about their role, but it did not consistently contribute to improved outcomes for evaluating UG performance. Implications for our PG-clinical teaching programme and how we evaluate our UG performance are discussed.Tracey Winning, Frances Greenwood, Dimitra Lekka

Grain boundary migration: misorientation dependence

Abstract The ability of grain boundaries (GB) to move has been found to be strongly dependent on crystallography, i.e. misorientation of the adjacent grains and orientation (inclination) of the GB in a crystal. Boundary mobility is rate-controlling in recrystallization and grain growth and thus, affects microstructure evolution and texture formation. This paper deals with recent advances in our understanding of misorientation and inclination dependence of grain boundary migration. © 2001 Elsevier Science Ltd. All rights reserved. A most important peculiarity of grain boundaries is their capillary driven motion technique, in which a curved GB ability to move. This grain boundary (GB) property has moves under the action of GB curvature, and the driving been found to be strongly dependent on grain boundary force p is provided by the GB surface tension g. Since the crystallography, i.e. misorientation of the adjacent grains true value of g is commonly not known, a reduced GB and orientation (inclination) of the GB in a crystal. Boundary mobility is rate-controlling in recrystallization [m / s], i.e. the same as the diffusion coefficient. An and grain growth and thus, affects microstructure evolution inherent feature of GB mobility is that it depends, apart and texture formation. Recent achievements in our underfrom the conventional thermodynamic variables (temperastanding of misorientation and inclination dependence of ture, pressure, etc.), on the misorientation of the adjacent grain boundary migration constitute the subject of this grains and GB orientation. A precise measurement and paper. thus, examination of the misorientation dependence of GB The mobility m is a quantitative measure of the kinetic mobility was made possible by tracking techniques of GB b properties of a grain boundary and thus, the principal migration in bicrystals. The distinctive properties of such parameter of the process of GB migration. It is defined as techniques are: controlled driving force, continuous track-GB velocity v per unit of driving force p: ing of GB displacement, accuracy and reproducibility of GB crystallography [**1]. As a first milestone, from v ] m 5 measurements with these techniques materials scientists b p became aware that properties of GBs with different A driving force for GB migration arises when a boundary misorientation can be essentially different. In particular, it displacement leads to a reduction of the total energy of the was established that GB mobility and its parameters are system. It is necessary to stress that the system need not be changing in a non-motonic way with the angle of mislimited to adjacent grains and a GB only, but may include orientation. external elastic, electrical or magnetic fields as well. There For special misorientations (low-S boundaries) the are two ways by which this driving force arises. The first activation enthalpy H of GB migration assumes a minim uses the free energy of a GB itself, the other utilizes a free mum. An example is shown i

Therapeutic benefits of proning to improve pulmonary gas exchange in severe respiratory failure: Focus on fundamentals of physiology

NEW FINDINGS: What is the topic of this review? The use of proning for improving pulmonary gas exchange in critically ill patients. What advances does it highlight? Proning places the lung in its ‘natural’ posture, and thus optimises the ventilation‐perfusion distribution, which enables lung protective ventilation and the alleviation of potentially life‐threatening hypoxaemia in COVID‐19 and other types of critical illness with respiratory failure. ABSTRACT: The survival benefit of proning patients with acute respiratory distress syndrome (ARDS) is well established and has recently been found to improve pulmonary gas exchange in patients with COVID‐19‐associated ARDS (CARDS). This review outlines the physiological implications of transitioning from supine to prone on alveolar ventilation‐perfusion ([Formula: see text]) relationships during spontaneous breathing and during general anaesthesia in the healthy state, as well as during invasive mechanical ventilation in patients with ARDS and CARDS. Spontaneously breathing, awake healthy individuals maintain a small vertical (ventral‐to‐dorsal) [Formula: see text] ratio gradient in the supine position, which is largely neutralised in the prone position, mainly through redistribution of perfusion. In anaesthetised and mechanically ventilated healthy individuals, a vertical [Formula: see text] ratio gradient is present in both postures, but with better [Formula: see text] matching in the prone position. In ARDS and CARDS, the vertical [Formula: see text] ratio gradient in the supine position becomes larger, with intrapulmonary shunting in gravitationally dependent lung regions due to compression atelectasis of the dorsal lung. This is counteracted by proning, mainly through a more homogeneous distribution of ventilation combined with a largely unaffected high perfusion dorsally, and a consequent substantial improvement in arterial oxygenation. The data regarding proning as a therapy in patients with CARDS is still limited and whether the associated improvement in arterial oxygenation translates to a survival benefit remains unknown. Proning is nonetheless an attractive and lung protective manoeuvre with the potential benefit of improving life‐threatening hypoxaemia in patients with ARDS and CARDS

Posttraumatic stress disorder and accelerated aging: PTSD and leukocyte telomere length in a sample of civilian women.

BACKGROUND: Studies in male combat veterans have suggested posttraumatic stress disorder (PTSD) is associated with shorter telomere length (TL). We examined the cross-sectional association of PTSD with TL in women exposed to traumas common in civilian life. METHODS: Data are from a substudy of the Nurses' Health Study II (N = 116). PTSD and subclinical PTSD were assessed in trauma-exposed women using diagnostic interviews. An array of health behaviors and conditions were assessed. DNA was extracted from peripheral blood leukocytes (collected 1996-1999). Telomere repeat copy number to single gene copy number (T/S) was determined by quantitative real-time PCR telomere assay. We used linear regression models to assess associations and examine whether a range of important health behaviors (e.g., cigarette smoking) and medical conditions (e.g., hypertension) previously associated with TL might explain a PTSD-TL association. We further examined whether type of trauma exposure (e.g., interpersonal violence) was associated with TL and whether trauma type might explain a PTSD-TL association. RESULTS: Relative to not having PTSD, women with a PTSD diagnosis had shorter log-transformed TL (β = -.112, 95% confidence interval (CI) = -0.196, -0.028). Adjustment for health behaviors and medical conditions did not attenuate this association. Trauma type was not associated with TL and did not account for the association of PTSD with TL. CONCLUSIONS: Our results add to growing evidence that PTSD may be associated with more rapid cellular aging as measured by telomere erosion. Moreover, the association could not be explained by health behaviors and medical conditions assessed in this study, nor by type of trauma exposure

The Role of Whole Blood Impedance Aggregometry and Its Utilisation in the Diagnosis and Prognosis of Patients with Systemic Inflammatory Response Syndrome and Sepsis in Acute Critical Illness

Objective: To assess the prognostic and diagnostic value of whole blood impedance aggregometry in patients with sepsis and SIRS and to compare with whole blood parameters (platelet count, haemoglobin, haematocrit and white cell count). Methods: We performed an observational, prospective study in the acute setting. Platelet function was determined using whole blood impedance aggregometry (multiplate) on admission to the Emergency Department or Intensive Care Unit and at 6 and 24 hours post admission. Platelet count, haemoglobin, haematocrit and white cell count were also determined. Results: 106 adult patients that met SIRS and sepsis criteria were included. Platelet aggregation was significantly reduced in patients with severe sepsis/septic shock when compared to SIRS/uncomplicated sepsis (ADP: 90.7±37.6 vs 61.4±40.6; p<0.001, Arachadonic Acid 99.9±48.3 vs 66.3±50.2; p = 0.001, Collagen 102.6±33.0 vs 79.1±38.8; p = 0.001; SD ± mean)). Furthermore platelet aggregation was significantly reduced in the 28 day mortality group when compared with the survival group (Arachadonic Acid 58.8±47.7 vs 91.1±50.9; p<0.05, Collagen 36.6±36.6 vs 98.0±35.1; p = 0.001; SD ± mean)). However haemoglobin, haematocrit and platelet count were more effective at distinguishing between subgroups and were equally effective indicators of prognosis. Significant positive correlations were observed between whole blood impedance aggregometry and platelet count (ADP 0.588 p<0.0001, Arachadonic Acid 0.611 p<0.0001, Collagen 0.599 p<0.0001 (Pearson correlation)). Conclusions: Reduced platelet aggregometry responses were not only significantly associated with morbidity and mortality in sepsis and SIRS patients, but also correlated with the different pathological groups. Whole blood aggregometry significantly correlated with platelet count, however, when we adjust for the different groups we investigated, the effect of platelet count appears to be non-significant

Post-traumatic stress disorder symptom duration and remission in relation to cardiovascular disease risk among a large cohort of women

Prior studies suggest that post-traumatic stress disorder (PTSD) is associated with elevated cardiovascular disease (CVD) risk, but effects of duration and remission of PTSD symptoms have rarely been evaluated. We examined the association of time-updated PTSD symptom severity, remission and duration with incident CVD risk (552 confirmed myocardial infarctions or strokes) over 20 years in 49 859 women in the Nurses’ Health Study II. Among women who reported trauma on the Brief Trauma Questionnaire, PTSD symptoms, assessed by a screener, were classified by symptom severity and chronicity: (a) no symptoms, (b) 1–3 ongoing, (c) 4–5 ongoing, (d) 6–7 ongoing, (e) 1–3 remitted, (f) 4–7 remitted symptoms. Inverse probability weighting was used to estimate marginal structural logistic regression models, adjusting for time-varying and time-invariant confounders. Compared with women with no trauma exposure, women with trauma/no PTSD [odds ratio (OR) 1.30, 95% confidence interval (CI) 1.03–1.65] and women with trauma/6–7 symptoms (OR 1.69, 95% CI 1.08–2.63) had elevated risk of CVD; women with remitted symptoms did not have elevated CVD risk. Among women exposed to trauma, every 5 additional years of PTSD symptomology was associated with 9% higher CVD incidence compared with women with trauma/no PTSD. The findings suggest that alleviating PTSD symptoms shortly after onset may attenuate CVD risk

Post-traumatic Stress Disorder and 20-Year Physical Activity Trends Among Women

Introduction: Post-traumatic stress disorder (PTSD) may be associated with physical inactivity, a modifiable lifestyle factor that contributes to risk of cardiovascular and other chronic diseases; however, no study has evaluated the association between PTSD onset and subsequent physical activity (PA) changes. Method: Analyses were conducted between October 2014 and April 2016, using data from the ongoing Nurses’ Health Study II (N=50,327). Trauma exposure and PTSD symptoms were assessed using two previously validated measures, the Brief Trauma Questionnaire and Short Screening Scale for DSM-IV PTSD. Average PA (hours/week) was assessed using self-report measures at six time points across 20 years (1989–2009). Linear mixed models with time-updated PTSD assessed differences in PA trajectories by trauma/PTSD status. Among a subsample of women whose trauma/PTSD onset during follow-up, group differences in PA patterns before and after onset were assessed using linear spline models. Results: PA decreased more steeply over time among trauma-exposed women reporting four or five (β= –2.5E–3, SE=1.0E–3, p=0.007) or six or seven PTSD symptoms (β= –6.7E–3, SE=1.1E–3, p<0.001) versus women without trauma exposure, adjusting for potential confounders. Among a subsample of women whose trauma/PTSD symptoms onset during follow-up, no differences in PA were observed prior to onset; after onset, women with six or seven PTSD symptoms had a steeper decline (β= –17.1E–3, SE=4.2E–3, p<0.001) in PA over time than trauma-exposed women without PTSD. Conclusions: Decreases in PA associated with PTSD symptoms may be a pathway through which PTSD influences cardiovascular and other chronic diseases

Post-traumatic stress disorder symptoms and risk of hypertension over 22 years in a large cohort of younger and middle-aged women

Background Posttraumatic stress disorder (PTSD) has been linked to hypertension, but most research on PTSD and hypertension is cross-sectional, and potential mediators have not been clearly identified. Moreover, PTSD is twice as common in women than in men, but understanding of the PTSD-hypertension relation in women is limited. We examined trauma exposure and PTSD symptoms in relation to incident hypertension over 22 years in 47,514 civilian women in the Nurses’ Health Study II. Methods We used proportional hazards models to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for new-onset hypertension (N=15,837). Results PTSD symptoms assessed with a screen were modestly associated with incident hypertension in a dose-response fashion after adjusting for potential confounders. Compared to women with no trauma exposure, women with 6–7 PTSD symptoms had the highest risk of developing hypertension (HR=1.20 [95% CI, 1.12–1.30]), followed by women with 4–5 symptoms (HR=1.17 [95% CI, 1.10–1.25]), women with 1–3 symptoms (HR=1.12 [95% CI, 1.06–1.18]), and trauma-exposed women with no symptoms (HR=1.04 [95% CI, 1.00–1.09]). Findings were maintained, although attenuated, adjusting for hypertension-relevant medications, medical risk factors, and health behaviors. Higher body mass index and antidepressant use accounted for 30% and 21% of the PTSD symptom-hypertension association. Conclusions Screening for hypertension and reducing unhealthy lifestyle factors, particularly obesity, in women with PTSD may hold promise for offsetting cardiovascular risk

Associations of Trauma Exposure and Posttraumatic Stress Symptoms With Venous Thromboembolism Over 22 Years in Women

Background: Trauma exposure and posttraumatic stress disorder (PTSD) have been linked to myocardial infarction and stroke in women, with biological and behavioral mechanisms implicated in underlying risk. The third most common cardiovascular illness, venous thromboembolism (VTE), is a specific health risk for women. Given previous associations with other cardiovascular diseases, we hypothesized that high levels of trauma and PTSD symptoms would be associated with higher risk of incident VTE in younger and middle‐aged women. Methods and Results: We used proportional hazards models to estimate hazard ratios (HRs) and 95% CIs for new‐onset VTE (960 events) over 22 years in 49 296 women in the Nurses’ Health Study II. Compared to no trauma exposure, both trauma exposure and PTSD symptoms were significantly associated with increased risk of developing VTE, adjusting for demographics, family history, and childhood adiposity. Women with the most PTSD symptoms exhibited the greatest risk elevation: trauma/6 to 7 symptoms: HR=2.42 (95% CI, 1.83–3.20); trauma/4 to 5 symptoms: HR=2.00 (95% CI, 1.55–2.59); trauma/1 to 3 symptoms: HR=1.44 (95% CI, 1.12–1.84); trauma/no symptoms: HR=1.72 (95% CI, 1.43–2.08). Results were similar, although attenuated, when adjusting for VTE‐relevant medications, medical conditions, and health behaviors. Conclusions: Women with the highest PTSD symptom levels had nearly a 2‐fold increased risk of VTE compared to women without trauma exposure in fully adjusted models. Trauma exposure alone was also associated with elevated VTE risk. Trauma and PTSD symptoms may be associated with a hypercoagulable state. Treatment providers should be aware that women with trauma exposure and PTSD symptoms may be vulnerable to VTE

Changes in glycemic control from 1996 to 2006 among adults with type 2 diabetes: a longitudinal cohort study

<p>Abstract</p> <p>Background</p> <p>Our objectives were to examine temporal changes in HbA1c and lipid levels over a 10-year period and to identify predictors of metabolic control in a longitudinal patient cohort.</p> <p>Methods</p> <p>We identified all adults within our hospital network with T2DM who had HbA1c's measured in both 1996 and 2006 (longitudinal cohort). For patients with no data in 2006, we used hospital and social security records to distinguish patients lost to follow-up from those who died after 1996. We compared characteristics of the 3 baseline cohorts (longitudinal, lost to f/u, died) and examined metabolic trends in the longitudinal cohort.</p> <p>Results</p> <p>Of the 4944 patients with HbA1c measured in 1996, 1772 (36%) had an HbA1c measured in 2006, 1296 (26%) were lost to follow-up, and 1876 (38%) had died by 2006. In the longitudinal cohort, mean HbA1c decreased by 0.4 ± 1.8% over the ten-year span (from 8.2% ± 1.7% to 7.8% ± 1.4%) and mean total cholesterol decreased by 49.3 (± 46.5) mg/dL. In a multivariate model, independent predictors of HbA1c decline included older age (OR 1.41 per decade, 95% CI: 1.3-1.6, p < 0.001), baseline HbA1c (OR 2.9 per 1% increment, 2.6 - 3.2, p < 0.001), and speaking English (OR 2.1, 1.4-3.1, p < 0.001).</p> <p>Conclusions</p> <p>Despite having had diabetes for an additional 10 years, patients in our longitudinal cohort had better glycemic and cholesterol control in 2006 than 1996. Greatest improvements occurred in patients with the highest levels in the baseline year.</p