Rapid quasi-periodic oscillations in the relativistic jet of BL Lacertae.

Blazars are active galactic nuclei (AGN) with relativistic jets whose non-thermal radiation is extremely variable on various timescales1-3. This variability seems mostly random, although some quasi-periodic oscillations (QPOs), implying systematic processes, have been reported in blazars and other AGN. QPOs with timescales of days or hours are especially rare4 in AGN and their nature is highly debated, explained by emitting plasma moving helically inside the jet5, plasma instabilities6,7 or orbital motion in an accretion disc7,8. Here we report results of intense optical and γ-ray flux monitoring of BL Lacertae (BL Lac) during a dramatic outburst in 2020 (ref. 9). BL Lac, the prototype of a subclass of blazars10, is powered by a 1.7 × 108 MSun (ref. 11) black hole in an elliptical galaxy (distance = 313 megaparsecs (ref. 12)). Our observations show QPOs of optical flux and linear polarization, and γ-ray flux, with cycles as short as approximately 13 h during the highest state of the outburst. The QPO properties match the expectations of current-driven kink instabilities6 near a recollimation shock about 5 parsecs (pc) from the black hole in the wake of an apparent superluminal feature moving down the jet. Such a kink is apparent in a microwave Very Long Baseline Array (VLBA) image.

Comparison of nine different methods to assess fish communities in lentic flood-plain habitats.

This study compares the effectiveness and representativeness of electrofishing, snorkelling, seining, baited lift netting, multi-mesh gillnetting, baited fish traps, fyke netting, angling and longline fishing, considering three typical lentic flood-plain habitats at different times of day. Electrofishing was by far the most effective method yielding highest species richness, species trait representation and catch per unit of effort (CPUE), followed by seining. For single species like dace Leuciscus leuciscus, European ruffe Gymnocephalus cernua, common bream Abramis brama and silver bream Blicca bjoerkna, seining was more effective than electrofishing. With both methods, some species were more consistently caught during night, dusk or dawn than during daylight. All other methods tested cannot be generally recommended for fish community assessments in shallow backwaters due to their low representativeness of species inventory and generally low CPUE. Based on these results, electrofishing of 30 m transect replicates at different times of day for monitoring the fish community in shallow backwaters, can be recommended, enabling the maximum possible comparability to adjacent river habitats. Seining should be considered as an alternative if accessibility of habitats is restricted or electrofishing is prohibited. The 25 species detected in the backwaters also suggest that these habitats contribute a large proportion of fish diversity and should be included in standard assessments of river ecological status.

Clinical effectiveness of a silicone foam dressing for the prevention of heel pressure ulcers in critically ill patients: Border II Trial.

OBJECTIVE: Critically ill patients are at high risk of developing pressure ulcers (PU), with the sacrum and heels being highly susceptible to pressure injuries. The objective of our study was to evaluate the clinical effectiveness of a new multi-layer, self-adhesive soft silicone foam heel dressing to prevent PU development in trauma and critically ill patients in the intensive care unit (ICU). METHOD: A cohort of critically ill patients were enrolled at the Royal Melbourne Hospital. Each patient had the multi-layer soft silicone foam dressing applied to each heel on admission to the emergency department. The dressings were retained with a tubular bandage for the duration of the patients' stay in the ICU. The skin under the dressings was examined daily and the dressings were replaced every three days. The comparator for our cohort study was the control group from the recently completed Border Trial. RESULTS: Of the 191 patients in the initial cohort, excluding deaths, loss to follow-up and transfers to another ward, 150 patients were included in the final analysis. There was no difference in key demographic or physiological variables between the cohorts, apart from a longer ICU length of stay for our current cohort. No PUs developed in any of our intervention cohort patients compared with 14 patients in the control cohort (n=152; p<0.001) who developed a total of 19 heel PUs. CONCLUSION: We conclude, based on our results, that the multi-layer soft silicone foam dressing under investigation was clinically effective in reducing ICU-acquired heel PUs. The findings also support previous research on the clinical effectiveness of multi-layer soft silicone foam dressings for PU prevention in the ICU.

Fracturing across the multi-scales of diverse materials.

Everyone has to deal with fracturing of materials at one level or another, beginning from normal household chores and extending to the largest scale of observations reported for catastrophic events occurring on a geological level or even expanded to events in outer space. Such wide perspective is introduced in the current introduction of this theme issue. The follow-on organization of technical articles provides a flavour of the range in size scales at which fracturing occurs in a wide diversity of materials-from 'fracking' oil extraction and earth moving to laboratory testing of rock material and extending to the cracking of tooth enamel. Of important scientific interest are observations made and analysed at the smallest dimensions corresponding to the mechanisms by which fracture is either enhanced or hindered by permanent deformation or other processes. Such events are irrevocably linked to the atomic structure in all engineering materials, a sampling of which is presented, including results for crystalline and amorphous materials. Hooray for the broad subject description that is hoped to be appealing to the interested reader.

Poor numeracy skills are associated with glycaemic control in Type 1 diabetes.

AIMS: To assess the numeracy and literacy skills of individuals with Type 1 diabetes and determine if there is a relationship with achieved glycaemic control independent of their duration of diabetes, diabetes education, demographic and socio-economic factors. METHODS: One hundred and twelve patients completed the study (mean current age 43.8 ± 12.5 years, 47% male, mean duration of diabetes 22.0 ± 13.2 years) out of 650 randomly selected patients from the Bournemouth Diabetes and Endocrine Centre's diabetes register. The Skills for Life Initial Assessments were used to measure numeracy and literacy. These indicate skills levels up to level 2, equivalent to the national General Certificate of Secondary Education grades A*-C. HbA(1c) was also measured. Pearson's correlation was used to measure the correlation of numeracy and literacy scores with HbA(1c.) To compare mean HbA(1c) between those with or without level 2 skills, t-tests were used, and multiple linear regression was used to investigate whether any differences were independent of duration of diabetes, diabetes education, demographic and socio-economic factors. RESULTS: Literacy was not associated with achieved HbA(1c). In contrast, participants with numeracy skills at level 2 or above achieved an HbA(1c) lower than those with numeracy skills below level 2 (P = 0.027). Although higher socio-economic status was associated with lower mean HbA(1c) , the relationship between numeracy and HbA(1c) appeared to be independent of socio-economic factors. CONCLUSIONS: Low numeracy skills were adversely associated with diabetes control. Assessment of numeracy skills may be relevant to the structure of diabetes education programmes.

HbA1c 3 months after diagnosis predicts premature mortality in patients with new onset type 2 diabetes.

AIMS: To determine 5-year mortality rates, following the diagnosis of Type 2 diabetes, in a large local cohort of individuals with new onset of Type 2 diabetes seen within a few weeks of diagnosis in a single, community-based education programme. METHODS: We reviewed referrals for people with Type 2 diabetes to our service over 5 years from 1999 to 2003 and determined, via regression analysis, which factors contributed significantly to mortality rates up to the end of 2007. RESULTS: A total of 3781 new referrals were reviewed with an approximate doubling of referral rates over 5 years (546 in 1999-997 in 2003). Although the number of people developing the condition has increased, mortality rates over the 5 years from diagnosis has fallen from 11% in 1999-9% in 2003 (P < 0.005) Age at diagnosis was the strongest predictor of mortality (P < 0.001) but HbA(1c) at 3 months after diagnosis (P < 0.001), systolic (P < 0.001) and diastolic (P = 0.05) blood pressure, smoking status (P < 0.001) and gender (P = 0.04) were also significant predictors. CONCLUSIONS: Our retrospective analysis adds weight to evidence suggesting that referral rates for people with Type 2 diabetes are increasing rapidly and that mortality rates are reducing but that the reasons for this are multifactorial. In addition to blood pressure, smoking and gender, the HbA(1c) achieved 3 months after the initial diagnosis also appears to predict subsequent mortality. It may be appropriate to consider early and intensive intervention for individuals with new onset type 2 diabetes.

Causes of injuries in the mountains: a review of worldwide reports into accidents in mountaineering.

This review presents a selection of sources from the UK and around the world that have reported on both incidents and accidents in the mountains. Common themes are extracted to illustrate the circumstances under which accidents, injuries and fatalities occur and the underlying factors that have contributed to incidents in the first place. There is an attempt to dispel some 'myths' surrounding accidents in mountain based activities. The purpose of highlighting these issues is to allow those undertaking them to understand where the greatest risks lie. This enables the individual, team leaders, rescue services and those involved in the overall management of wilderness areas to plan accordingly, with the aim of reducing injuries and deaths.

Validation of the Full Outline of Unresponsiveness (FOUR) Scale for conscious state in the emergency department: comparison against the Glasgow Coma Scale.

OBJECTIVES: To determine (a) the inter-rater reliability of pairs of emergency doctors' and/or nurses' ratings of the Glasgow Coma Scale (GCS) and the Full Outline of Unresponsiveness (FOUR) Scale in emergency department (ED) patients, (b) the concurrent validity of the FOUR Scale using the GCS as the reference scale and (c) doctors' and nurses' knowledge and attitudes towards the GCS and FOUR Scale. METHODS: A prospective observational study was conducted using staff participants' ratings for a convenience sample of ED patients requiring quantification of conscious state. Participating doctors and nurses attended a formal training session on the correct use of the GCS and FOUR Scale. Pairs of clinicians then independently completed the GCS and FOUR Scale on patients within 5 min of each other. RESULTS: 140 clinicians were recruited and trained in the use of the GCS and FOUR Scale. A total of 217 observations were performed on 203 patients presenting to the ED with various conditions. The inter-rater reliability for the FOUR Scale was greater than that of the GCS (FOUR: к = 0.76, p < 0.01; GCS: к = 0.59, p < 0.01). The reliability for both the GCS and the FOUR Scale was poorest within doctor-nurse pairs. CONCLUSION: The FOUR Scale showed greater reliability than the GCS in ED patients using ED clinicians as raters. A larger study of ED patients is warranted to determine the predictive validity of the FOUR Scale and to further examine the reliability of the scale in various patient populations.

Satisfaction with the emergency department environment decreases with length of stay.

OBJECTIVE: To determine the emergency department (ED) environmental factors associated with patient satisfaction. METHODS: A prospective, observational study in a university-affiliated tertiary-referral ED and associated observation unit (OU). The ED environment was evaluated with a structured questionnaire, scored using a 100-mm visual analogue scale. Patients who stayed in the ED over 8 h (long-stay ED; LSED) were compared with those who stayed less than 4 h (short-stay ED; SSED) and with a control group admitted to the OU. RESULTS: A total of 233 patients was enrolled, overall satisfaction in SSED was 81% (95% CI 70.1 to 88.7), 69% in LSED (95% CI 57.4 to 78.7) and 84% in OU (95% CI 73.6 to 91.0). The most important environmental factors were cleanliness (median importance 95, interquartile range (IQR) 81-98) and communication with medical staff (94, IQR 80-98) and family (92, IQR 74-98). The least important factors were access to nature (38, IQR 19-65), a natural light source (50, IQR 24-74) and ability to sit out of bed (52, IQR 26-75). Factors rated high for importance but low for satisfaction were ED noise levels (median difference 40, IQR 3-70), ED trolley comfort (19, IQR 6-50) and food quality (12, IQR -4-29). CONCLUSION: Patients who spend over 8 h in the ED are less satisfied with their environment than either those who spend less than 4 h or patients in an OU. Importantly, distinct, amenable factors can be identified. These should be addressed to improve patients' overall ED management and satisfaction.

Theme groups at thirty.

This article is a 30-year retrospective of the emergence of the theme group movement in college counseling centers and in psychotherapy in general. It describes the evolution of interventions in this modality, defines and describes their unique features and approaches, and illustrates, via comparison of two theme groups on grief, the maturation and incorporation of more evidence-based and apt formats and dynamics over that period of development.

Donation intentions among African American college students: decisional balance and self-efficacy measures.

Although the need for transplantation among African Americans is high, their donation rates are disproportionately low. This study describes the development and validation of culturally adapted psychosocial measures, including Transtheoretical Model constructs, Stages of Change, Decisional Balance, and Self-efficacy, related to deceased organ and tissue donation for an African American college population. Exploratory and confirmatory analyses for Decisional Balance and Self-efficacy measures demonstrated factor structures similar to previous studies of other behavioral applications, indicated excellent model fit and showed good internal and external validity. This study developed brief measures with good psychometric properties for an emerging behavior change domain in a new population.

Febrile adults presenting to the emergency department: outcomes and markers of serious illness.

OBJECTIVES: To determine outcomes and markers of serious illness for febrile patients presenting to an adult emergency department. METHODS: A prospective cohort study of patients presenting to the emergency department with a temperature >or=38 degrees C. Medical staff obtained demographic data and risk factor profiles while assessing each febrile patient. All were followed up to determine death, admission to intensive care, length of stay in hospital, or subsequent admission to hospital within 30 days. Univariate and multivariate analysis determined which factors were markers of serious illness. RESULTS: For febrile adults admitted to hospital 3.0% died, 6.1% were admitted to intensive care, median length of stay in hospital was 7.2 days. Independent risk factors were-death: age (OR = 1.04), respiratory rate (OR = 1.06), white cell count (OR = 1.02), cardiac disease (OR = 3.3), and jaundice (OR = 21.4). Admission to intensive care: respiratory rate (OR = 1.1), pulse rate (OR = 1.03), and jaundice (OR = 5.1). Increased length of hospital stay: age (p<0.01), jaundice (p<0.01), respiratory rate (p = 0.01), focal neurological signs (p = 0.01), and changed mental state (p = 0.04). For febrile adults sent home 7.9% required admission to hospital within 30 days. Risk factors were respiratory rate (OR = 1.2), being female (OR = 5.36), malignancy (OR = 15.3), and cardiac disease (OR = 19.7). Initially having no focus of infection was protective (OR = 0.13). No febrile patient sent home from the emergency department died or required admission to intensive care. CONCLUSIONS: Few febrile adults presenting to the emergency department suffer an adverse outcome suggesting effective risk stratification is occurring. The identification of factors associated with adverse events may further improve this process.

A prospective randomized study to evaluate the renoprotective action of beating heart coronary surgery in low risk patients.

OBJECTIVES: Cardiopulmonary bypass (CPB) is widely regarded as an important contributor to renal failure, a well recognized complication following coronary artery surgery (coronary artery bypass grafting (CABG)). Anecdotally off-pump coronary surgery (OPCAB) is considered renoprotective. We examine the extent of renal glomerular and tubular injury in low-risk patients undergoing either OPCAB or on-pump coronary artery bypass (ONCAB). METHODS: Forty low-risk patients with normal preoperative cardiac and renal functions awaiting elective CABG were prospectively randomized into those undergoing OPCAB (n=20) and ONCAB (n=20). Glomerular and tubular injury were measured respectively by urinary excretion of microalbumin and retinol binding protein (RBP) indexed to creatinine (Cr). Daily measurements were taken from admission to postoperative day 5. Fluid balance, serum Cr and blood urea were also monitored. RESULTS: No mortality or renal complication were observed. Both groups had similar demographic makeup, Parsonnet score, functional status and extent of coronary revascularization (2.1+/-1.0 vs. 2.5+/-0.7 grafts; P=0.08). Serum Cr and blood urea remained normal in both groups throughout the study. A significant and similar rise in urinary RBP:Cr occurred in both groups peaking on day 1 (3183+/-2534 vs. 4035+/-4079; P=0.43) before reapproximating baseline levels. These trends were also observed with urinary microalbumin:Cr (5.05+/-2.66 vs. 6.77+/-5.76; P=0.22). Group B patients had a significantly more negative fluid balance on postoperative day 2 (-183+/-1118 vs. 637+/-847 ml; P=0.03). CONCLUSIONS: Although renal complication or serum markers of kidney dysfunction were absent, sensitive indicators revealed significant and similar injury to renal tubules and glomeruli following either OPCAB or ONCAB. These results suggest that avoidance of CPB does not offer additional renoprotection to patients at low risk of perioperative renal insult during CABG.

Production of calves from G1 fibroblasts.

Since the landmark study of Wilmut et al. describing the birth of a cloned lamb derived from a somatic cell nucleus, there has been debate about the donor nucleus cell cycle stage required for somatic cell nuclear transfer (NT). Wilmut et al. suggested that induction of quiescence by serum starvation was critical in allowing donor somatic cells to support development of cloned embryos. In a subsequent report, Cibelli et al. proposed that G0 was unnecessary and that calves could be produced from actively dividing fibroblasts. Neither study conclusively documented the importance of donor cell cycle stage for development to term. Other laboratories have had success with NT in several species, and most have used a serum starvation treatment. Here we evaluate methods for producing G0 and G1 cell populations and compare development following NT. High confluence was more effective than serum starvation for arresting cells in G0. Pure G1 cell populations could be obtained using a "shake-off" procedure. No differences in in vitro development were observed between cells derived from the high-confluence treatment and from the "shake-off" treatment. However, when embryos from each treatment were transferred to 50 recipients, five calves were obtained from embryos derived from "shake-off" cells, whereas no embryos from confluent cells survived beyond 180 days of gestation. These results indicate that donor cell cycle stage is important for NT, particularly during late fetal development, and that actively dividing G1 cells support higher development rates than cells in G0.

Effect of fibroblast donor cell age and cell cycle on development of bovine nuclear transfer embryos in vitro.

The effects of cell cycle stage and the age of the cell donor animal on in vitro development of bovine nuclear transfer embryos were investigated. Cultures of primary bovine fibroblasts were established from animals of various ages, and the in vitro life span of these cell lines was analyzed. Fibroblasts from both fetuses and calves had similar in vitro life spans of approximately 30 population doublings (PDs) compared with 20 PDs in fibroblasts obtained from adult animals. When fibroblasts from both fetuses and adult animals were cultured as a population, the percentage of cells in G1 increased linearly with time, whereas the percentage of S-phase cells decreased proportionately. Furthermore, the percentage of cells in G1 at a given time was higher in adult fibroblasts than in fetal fibroblasts. To study the individual cells from a population, a shake-off method was developed to isolate cells in G1 stage of the cell cycle and evaluate the cell cycle characteristics of both fetal and adult fibroblasts from either 25% or 100% confluent cultures. Irrespective of the age, the mean cell cycle length in isolated cells was shorter (9.6-15.5 h) than that observed for cells cultured as a population. Likewise, the length of the G1 stage in these isolated cells, as indicated by 5-bromo-deoxyuridine labeling, lasted only about 2-3 h. There were no differences in either the number of cells in blastocysts or the percentage of blastocysts between the embryos reconstructed with G1 cells from 25% or 100% confluent cultures of fetal or adult cell lines. This study suggests that there are substantial differences in cell cycle characteristics in cells derived from animals of different ages or cultured at different levels of confluence. However, these factors had no effect on in vitro development of nuclear transfer embryos.

Myocardial perfusion imaging in evaluation of undiagnosed acute chest pain.

Myocardial perfusion imaging is a relatively new technique in the emergency department management of acute chest pain. With improved sensitivity and specificity compared to traditional methods of risk stratification, an abnormal scan rapidly identifies individuals with acute perfusion abnormalities and allows the appropriate utilization of limited resources. Conversely, a normal scan allows prompt hospital discharge and is associated with excellent outcomes both in the short and medium terms. Acute chest pain myocardial perfusion imaging has been demonstrated to alter patient management and disposition and its routine use results in decreased costs in the intermediate risk population.

When (not if) evaluation flexibility is desirable. Examples from the CPHPE initiative.

The evaluation literature often debates whether evaluators should be flexible in evaluation design and activities in order to collaborate with program directors and be responsive to programming needs. Two conditions are specified under which evaluation flexibility is not only desirable but essential. Two examples from the cluster evaluation of the W. K. Kellogg Foundation's Community Partnerships for Health Professions Education initiative are provided to illustrate why flexibility under these conditions proved to be essential. One of the examples, related to the "community" involvement in the initiative, illustrates the need for flexibility as programs experience goals clarification. The other example, related to the coincidental national health care reform efforts, illustrates the need for flexibility both to capture programs' efforts to protect their integrity and to ensure against spurious conclusions as a result of external turbulence in policy environments. How the cluster evaluation team addressed these issues is also described.

Evaluating the impact on public policy of foundation-sponsored programs in the health professions.

The leaders of national philanthropic foundations have long been active in informing public policy makers about their organizations' accomplishments and lessons learned in health care and other issues. The public policy context also is seen increasingly as an important factor influencing changes in the health care market. This article outlines how public policy was monitored and evaluated in a recent initiative in health care by a prominent national foundation. The markers of policy change in the evaluation of this initiative represented a mixture of the initiative's efforts to inform policy makers, the success the participant projects had in making policy makers aware of the initiative's goals, and actual changes in policy outcomes.