Reperfusion injury following cerebral ischemia: pathophysiology, MR imaging, and potential therapies

INTRODUCTION: Restoration of blood flow following ischemic stroke can be achieved by means of thrombolysis or mechanical recanalization. However, for some patients, reperfusion may exacerbate the injury initially caused by ischemia, producing a so-called “cerebral reperfusion injury”. Multiple pathological processes are involved in this injury, including leukocyte infiltration, platelet and complement activation, postischemic hyperperfusion, and breakdown of the blood–brain barrier. METHODS/RESULTS AND CONCLUSIONS: Magnetic resonance imaging (MRI) can provide extensive information on this process of injury, and may have a role in the future in stratifying patients’ risk for reperfusion injury following recanalization. Moreover, different MRI modalities can be used to investigate the various mechanisms of reperfusion injury. Antileukocyte antibodies, brain cooling and conditioned blood reperfusion are potential therapeutic strategies for lessening or eliminating reperfusion injury, and interventionalists may play a role in the future in using some of these therapies in combination with thrombolysis or embolectomy. The present review summarizes the mechanisms of reperfusion injury and focuses on the way each of those mechanisms can be evaluated by different MRI modalities. The potential therapeutic strategies are also discussed

Coronary Artery Bypass Graft Surgery : Discharge Planning for Successful Recovery

Background. Coronary artery bypass graft (CABG) surgery is a lifesaving intervention, but the early recovery period presents a number of challenges for patients, carers and nurses. Early and adequate discharge planning based on in-depth knowledge of the post discharge experience can help to ensure optimal recovery. Aim. This paper reports a study to examine the range of postdischarge issues, concerns and needs of patients and their family carers after discharge after CABG surgery, and explore their perceptions of unmet needs 1 year later. Methods. A two-phase naturalistic inquiry was undertaken. Interviews were conducted with 30 patients and their carers 45 weeks after coronary artery bypass grafting (phase 1) and 1 year after the initial interview (phase 2). Thematic analysis was used to identify the major concerns of participants. Findings. Almost half the patients experienced heart surgery as a huge personal shock. Adjusting to life afterwards was difficult, and they experienced a variety of changes, including pain. An unexpected finding was a heightened sense of body awareness and the need for postoperative physical adjustments. The financial implications of surgery were a major burden. Lifestyle adjustments were important and led to suggestions for support services, using telephone support and/or community patient networks. All participants recommended strengthening discharge planning with more accurate information about what to expect during recovery, to help them anticipate fluctuations in health and wellbeing. Carers experienced a wide range of unanticipated feelings during early recovery and had to deal with a number of personal changes. Conclusions. The findings suggest a need to improve discharge preparation and provide enhanced home support services. Further research should evaluate models of periodic follow-up and mechanisms for mutual support, and compare the experiences of cardiac patients and their carers with those of other surgical cohorts. What is already known about this topic The numbers of surgical interventions for cardiac disease will continue to increase, given the effectiveness of surgery in reducing mortality. Discharge plans addressing the early recovery phase after coronary artery bypass graft surgery have thus far overlooked a broad range of longer-term patient needs. Little attention has been to the self-defined needs of carers of these patients. What this paper adds Patients' and carers' needs for information and support following coronary artery bypass graft surgery are not being met. Patients' and carers' would like more professional support and follow-up after discharge. Heightened body awareness and adjustment to postoperative physical changes are important issues in this client group

Tevatron Run II combination of the effective leptonic electroweak mixing angle

Drell-Yan lepton pairs produced in the process pp→â.,"+â.,"-+X through an intermediate γ∗/Z boson have an asymmetry in their angular distribution related to the spontaneous symmetry breaking of the electroweak force and the associated mixing of its neutral gauge bosons. The CDF and D0 experiments have measured the effective-leptonic electroweak mixing parameter sin2θefflept using electron and muon pairs selected from the full Tevatron proton-antiproton data sets collected in 2001-2011, corresponding to 9-10 fb-1 of integrated luminosity. The combination of these measurements yields the most precise result from hadron colliders, sin2θefflept=0.23148±0.00033. This result is consistent with, and approaches in precision, the best measurements from electron-positron colliders. The standard model inference of the on-shell electroweak mixing parameter sin2θW, or equivalently the W-boson mass MW, using the zfitter software package yields sin2θW=0.22324±0.00033 or equivalently, MW=80.367±0.017 GeV/c2

Liberal democracy and sustainability

Although theory strongly suggests that liberal democracies should perform better than autocracies on sustainability indicators, the empirical evidence is unclear. Using multivariate statistical techniques, political factors such as the stability of the system, public opinion, the nature of the party system and other institutional features such as presidentialism are considered. Liberal democracy is given qualified endorsement: it typically promotes weak sustainability, and stable core autocracies perform worse on strong sustainability measures than stable core democracies. Presidentialism generally is bad for sustainability. However, there is no compelling evidence that public opinion matters, even allowing for the intervening effects of the party system and institutional structure, which raises questions about the nature of the democratic process

Analysis of spacing for spotted gum plantations for maximizing merchantable logs' volume in Southeast Queensland, Australia

Spotted gum (Corymbia citriodora subspecies Variegata) has the potential to be the major hardwood species for large-scale plantations in Southeast Queensland, Australia, but production research is limited due to the lack of age of research plots. Optimal spacing is a major subject of concern. Based on time series data from a spotted gum experiment site, growth performance was analyzed for five spacing levels: 11.3 m × 11.3 m (78 stems ha−1), 7.4 m × 7.4 m (182 stems ha−1), 5.4 m × 5.4 m (343 stems ha−1), 3.6 m × 3.6 m (771 stems ha−1), and 2.9 m × 2.9 m (1189 stems ha−1). The major objective was assumed to be to maximize total merchantable log volume. A growth model was produced, and the mean diameter at breast height (DBH) and total merchantable log volume for each spacing level at a range of harvesting ages were estimated. From the analysis, the spacing level of 5.4 m × 5.4 m was foundto be optimal for maximizing merchantable log volume to a 10-cm small-end diameter. Further analysis of mean DBH, height, and volume of the largest 200 and 250 trees from this spacing level indicates that merchantable log volume could be maximized by retaining the 250 largest trees ha−1. The total financial revenue from the best spacing level in 25 and 30 yr are predicted to be Australian dollars (A$) 13,637 and A$17,779 ha−1, respectively. If full rotation data could be obtained, more reliable models could be produced, and a more accurate financial estimate could be made