Showing papers by "University of Newcastle published in 2008"
TL;DR: The Bodipy family, first developed as luminescent tags and laser dyes, has become a cornerstone for these new applications and the near future looks extremely bright for "porphyrin's little sister".
Abstract: The world of organic luminophores has been confined for a long time to fairly standard biological labeling applications and to certain analytical tests. Recently, however, the field has undergone a major change of direction, driven by the dual needs to develop novel organic electronic materials and to fuel the rapidly emerging nanotechnologies. Among the many diverse fluorescent molecules, the Bodipy family, first developed as luminescent tags and laser dyes, has become a cornerstone for these new applications. The near future looks extremely bright for "porphyrin's little sister".
2,705 citations
TL;DR: A simple classification of the most important types of predictive control is introduced, and each one of them is explained including some application examples.
Abstract: Predictive control is a very wide class of controllers that have found rather recent application in the control of power converters. Research on this topic has been increased in the last years due to the possibilities of today's microprocessors used for the control. This paper presents the application of different predictive control methods to power electronics and drives. A simple classification of the most important types of predictive control is introduced, and each one of them is explained including some application examples. Predictive control presents several advantages that make it suitable for the control of power converters and drives. The different control schemes and applications presented in this paper illustrate the effectiveness and flexibility of predictive control.
1,389 citations
TL;DR: From the literature review, it would appear that the definition of therapeutic compliance is adequately resolved and the factors related to compliance may be better categorized as “soft” and “hard” factors as the approach in countering their effects may differ.
Abstract: Objective
To explore and evaluate the most common factors causing therapeutic non-compliance.
1,151 citations
TL;DR: In the Sydney Myopia Study as discussed by the authors, the authors assessed the relationship of near, mid-working distance, and outdoor activities with prevalence of myopia in school-aged children and found that higher levels of outdoor activity (sport and leisure activities) were associated with more hyperopic refractions and lower myopia prevalence in the 12-year-old students.
1,022 citations
TL;DR: In this article, the authors present a review of methods for estimating evaporation from landscapes, regions and larger geographic extents, with remotely sensed surface temperatures, and highlight uncertainties and limitations associated with those estimation methods.
Abstract: This paper reviews methods for estimating evaporation from landscapes, regions and larger geographic extents, with remotely sensed surface temperatures, and highlights uncertainties and limitations associated with those estimation methods. Particular attention is given to the validation of such approaches against ground based flux measurements. An assessment of some 30 published validations shows an average root mean squared error value of about 50 W m−2 and relative errors of 15–30%. The comparison also shows that more complex physical and analytical methods are not necessarily more accurate than empirical and statistical approaches. While some of the methods were developed for specific land covers (e.g. irrigation areas only) we also review methods developed for other disciplines, such as hydrology and meteorology, where continuous estimates in space and in time are needed, thereby focusing on physical and analytical methods as empirical methods are usually limited by in situ training data. This review also provides a discussion of temporal and spatial scaling issues associated with the use of thermal remote sensing for estimating evaporation. Improved temporal scaling procedures are required to extrapolate instantaneous estimates to daily and longer time periods and gap-filling procedures are needed when temporal scaling is affected by intermittent satellite coverage. It is also noted that analysis of multi-resolution data from different satellite/sensor systems (i.e. data fusion) will assist in the development of spatial scaling and aggregation approaches, and that several biological processes need to be better characterized in many current land surface models.
1,019 citations
TL;DR: The LBA model successfully accommodates empirical phenomena from binary and multiple choice tasks that have proven difficult for other theoretical accounts, and is encouraging in a field beset by the tradeoff between complexity and completeness.
951 citations
TL;DR: Much research in emulsions can be applied to foam systems, however evidence would suggest foam systems are under a number of additional constraints, and the stability 'window' for particles is smaller, in terms of size and contact angle ranges.
898 citations
TL;DR: The biology of eosinophils is summarized, focusing on transcriptional regulation of eOSinophil differentiation, characterization of the growing properties of eOsinophIL granule proteins, surface proteins and pleiotropic mediators, and molecular mechanisms of Eosinophile degranulation.
Abstract: Eosinophils are pleiotropic multifunctional leukocytes involved in initiation and propagation of diverse inflammatory responses, as well as modulators of innate and adaptive immunity. In this review, the biology of eosinophils is summarized, focusing on transcriptional regulation of eosinophil differentiation, characterization of the growing properties of eosinophil granule proteins, surface proteins and pleiotropic mediators, and molecular mechanisms of eosinophil degranulation. New views on the role of eosinophils in homeostatic function are examined, including developmental biology and innate and adaptive immunity (as well as their interaction with mast cells and T cells) and their proposed role in disease processes including infections, asthma, and gastrointestinal disorders. Finally, strategies for targeted therapeutic intervention in eosinophil-mediated mucosal diseases are conceptualized.
768 citations
TL;DR: The testes contain an elaborate array of antioxidant enzymes and free radical scavengers to ensure that the twin spermatogenic and steroidogenic functions of this organ are not impacted by oxidative stress.
Abstract: Spermatogenesis is an extremely active replicative process capable of generating approxi mately 1,000 sperm a second. The high rates of cell division inherent in this process imply correspondingly high rates of mitochondrial oxygen consumption by the germinal epithelium. However, the poor vascularization of the testes means that oxygen tensions in this tissue are low1 and that competition for this vital element within the testes is extremely intense. Since both spermatogenesis2 and Leydig cell steroidogenesis3,4 are vulnerable to oxidative stress, the low oxygen tension that characterizes this tissue may be an important component of the mechanisms by which the testes protects itself from free radical-mediated damage. In addition, the testes contain an elaborate array of antioxidant enzymes and free radical scavengers to ensure that the twin spermatogenic and steroidogenic functions of this organ are not impacted by oxidative stress. These antioxidant defence systems are of major importance because peroxidative damage is currently regarded as the single most important cause of impaired testicular function underpinning the pathological consequences of a wide range of conditions from testicular torsion to diabetes and xenobiotic exposure. This chapter sets out the specific nature of these antioxidant defence systems and also reviews the factors that have been found to impair their activity, precipitating a state of oxidative stress in the testes and impairing the latter’s ability to produce viable spermatozoa capable of initiating and supporting embryonic development.
731 citations
TL;DR: The new medulloblastoma classification presented in this study will greatly enhance the understanding of this heterogeneous disease and enable a better selection and evaluation of patients in clinical trials, and it will support the development of new molecular targeted therapies.
Abstract: Background: Medulloblastoma is the most common malignant brain tumor in children. Despite recent improvements in cure rates, prediction of disease outcome remains a major challenge and survivors suffer from serious therapy-related side-effects. Recent data showed that patients with WNT-activated tumors have a favorable prognosis, suggesting that these patients could be treated less intensively, thereby reducing the side-effects. This illustrates the potential benefits of a robust classification of medulloblastoma patients and a detailed knowledge of associated biological mechanisms. Methods and Findings: To get a better insight into the molecular biology of medulloblastoma we established mRNA expression profiles of 62 medulloblastomas and analyzed 52 of them also by comparative genomic hybridization (CGH) arrays. Five molecular subtypes were identified, characterized by WNT signaling (A; 9 cases), SHH signaling (B; 15 cases), expression of neuronal differentiation genes (C and D; 16 and 11 cases, respectively) or photoreceptor genes (D and E; both 11 cases). Mutations in β-catenin were identified in all 9 type A tumors, but not in any other tumor. PTCH1 mutations were exclusively identified in type B tumors. CGH analysis identified several fully or partly subtype-specific chromosomal aberrations. Monosomy of chromosome 6 occurred only in type A tumors, loss of 9q mostly occurred in type B tumors, whereas chromosome 17 aberrations, most common in medulloblastoma, were strongly associated with type C or D tumors. Loss of the inactivated X-chromosome was highly specific for female cases of type C, D and E tumors. Gene expression levels faithfully reflected the chromosomal copy number changes. Clinicopathological features significantly different between the 5 subtypes included metastatic disease and age at diagnosis and histology. Metastatic disease at diagnosis was significantly associated with subtypes C and D and most strongly with subtype E. Patients below 3 yrs of age had type B, D, or E tumors. Type B included most desmoplastic cases. We validated and confirmed the molecular subtypes and their associated clinicopathological features with expression data from a second independent series of 46 medulloblastomas. Conclusions: The new medulloblastoma classification presented in this study will greatly enhance the understanding of this heterogeneous disease. It will enable a better selection and evaluation of patients in clinical trials, and it will support the development of new molecular targeted therapies. Ultimately, our results may lead to more individualized therapies with improved cure rates and a better quality of life.
680 citations
TL;DR: The data imply a common methanogenic biodegradation mechanism in subsurface degraded oil reservoirs, resulting in consistent patterns of hydrocarbon alteration, and the common association of dry gas with severely degraded oils observed worldwide.
Abstract: Biodegradation of crude oil in subsurface petroleum reservoirs has adversely affected the majority of the world's oil, making recovery and refining of that oil more costly. The prevalent occurrence of biodegradation in shallow subsurface petroleum reservoirs has been attributed to aerobic bacterial hydrocarbon degradation stimulated by surface recharge of oxygen-bearing meteoric waters. This hypothesis is empirically supported by the likelihood of encountering biodegraded oils at higher levels of degradation in reservoirs near the surface. More recent findings, however, suggest that anaerobic degradation processes dominate subsurface sedimentary environments, despite slow reaction kinetics and uncertainty as to the actual degradation pathways occurring in oil reservoirs. Here we use laboratory experiments in microcosms monitoring the hydrocarbon composition of degraded oils and generated gases, together with the carbon isotopic compositions of gas and oil samples taken at wellheads and a Rayleigh isotope fractionation box model, to elucidate the probable mechanisms of hydrocarbon degradation in reservoirs. We find that crude-oil hydrocarbon degradation under methanogenic conditions in the laboratory mimics the characteristic sequential removal of compound classes seen in reservoir-degraded petroleum. The initial preferential removal of n-alkanes generates close to stoichiometric amounts of methane, principally by hydrogenotrophic methanogenesis. Our data imply a common methanogenic biodegradation mechanism in subsurface degraded oil reservoirs, resulting in consistent patterns of hydrocarbon alteration, and the common association of dry gas with severely degraded oils observed worldwide. Energy recovery from oilfields in the form of methane, based on accelerating natural methanogenic biodegradation, may offer a route to economic production of difficult-to-recover energy from oilfields.
TL;DR: Functional neuroimaging showed that cueing for speed activates the striatum and the pre-supplementary motor area, brain structures that are part of a closed-loop motor circuit involved in the preparation of voluntary action plans.
Abstract: Human decision-making almost always takes place under time pressure. When people are engaged in activities such as shopping, driving, or playing chess, they have to continually balance the demands for fast decisions against the demands for accurate decisions. In the cognitive sciences, this balance is thought to be modulated by a response threshold, the neural substrate of which is currently subject to speculation. In a speed decision-making experiment, we presented participants with cues that indicated different requirements for response speed. Application of a mathematical model for the behavioral data confirmed that cueing for speed lowered the response threshold. Functional neuroimaging showed that cueing for speed activates the striatum and the pre-supplementary motor area (pre-SMA), brain structures that are part of a closed-loop motor circuit involved in the preparation of voluntary action plans. Moreover, activation in the striatum is known to release the motor system from global inhibition, thereby facilitating faster but possibly premature actions. Finally, the data show that individual variation in the activation of striatum and pre-SMA is selectively associated with individual variation in the amplitude of the adjustments in the response threshold estimated by the mathematical model. These results demonstrate that when people have to make decisions under time pressure their striatum and pre-SMA show increased levels of activation.
TL;DR: The correlation of imatinib trough plasma concentrations with clinical responses, event-free survival (EFS), and adverse events (AEs) is described and it is suggested that an adequate plasma concentration ofImatinib is important for a good clinical response.
TL;DR: In this article, the authors focus on the pathways and key factors responsible for the differentiation of the various subsets of effector CD4 T cells, including Th1, Th2, and Th17 cells.
Abstract: Aberrant T-cell responses underpin a range of diseases, including asthma and allergy and autoimmune diseases. Pivotal immune elements of these diseases are the development of antigen-specific effector T-helper type 2 (Th2) cells, Th1 cells, or the recently defined Th17 cells that are associated with the clinical features and disease progression. In order to identify crucial processes in the pathogenesis of these diseases it is critical to understand how the development of these T cells occurs. The phenotype of a polarized T-cell that differentiates from a naive precursor is determined by the complex interaction of antigen-presenting cells with naive T cells and involves a multitude of factors, including the dominant cytokine environment, costimulatory molecules, type and load of antigen presented and a plethora of signaling cascades. The decision to take the immune response in a certain direction is not made by one signal alone, instead many different elements act synergistically, antagonistically and through positive feedback loops to activate a Th1, Th2, or Th17 immune response. The elucidation of the mechanisms of selection of T-cell phenotype will facilitate the development of therapeutic strategies to intervene in the development of deleterious T-cell responses. This review will focus on the pathways and key factors responsible for the differentiation of the various subsets of effector CD4 T cells. We will primarily discuss what is known of the Th1 and Th2 differentiation pathways, while also reviewing the emerging research on Th17 differentiation.
TL;DR: The sperm mitochondria make a significant contribution to the oxidative stress experienced by defective human spermatozoa, as well as the subcellular origins of this activity are unclear.
Abstract: Context: Male infertility has been linked with the excessive generation of reactive oxygen species (ROS) by defective spermatozoa. However, the subcellular origins of this activity are unclear. Objective: The objective of this study was to determine the importance of sperm mitochondria in creating the oxidative stress associated with defective sperm function. Method: Intracellular measurement of mitochondrial ROS generation and lipid peroxidation was performed using the fluorescent probes MitoSOX red and BODIPY C11 in conjunction with flow cytometry. Effects on sperm movement were measured by computer-assisted sperm analysis. Results: Disruption of mitochondrial electron transport flow in human spermatozoa resulted in generation of ROS from complex I (rotenone sensitive) or III (myxothiazol, antimycin A sensitive) via mechanisms that were independent of mitochondrial membrane potential. Activation of ROS generation at complex III led to the rapid release of hydrogen peroxide into the extracellular space, ...
TL;DR: Urgent action on the fundamental causes of climate change and appropriate management of critical elements of habitat structure (coral cover and topographic complexity) are key to ensuring long-term persistence of coral-reef fishes.
Abstract: Global climate change is having devastating effects on habitat structure in coral-reef ecosystems owing to extreme environmental sensitivities and consequent bleaching of reef-building scleractinian corals. Coral bleaching frequently causes immediate loss of live coral and may lead to longer-term declines in topographic complexity. This review identifies coral cover and topographic complexity as critical and distinct components of coral-reef habitats that shape communities of coral-reef fishes. Coral loss has the greatest and most immediate effect on fishes that depend on live corals for food or shelter, and many such fishes may face considerable risk of extinction with increasing frequency and severity of bleaching. Coral loss may also have longer-term consequences for fishes that require live corals at settlement, which are compounded by devastating effects of declining topographic complexity. Topographic complexity moderates major biotic factors, such as predation and competition, contributing to the high diversity of fishes on coral reefs. Many coral-reef fishes that do not depend on live coral are nonetheless dependent on the topographic complexity provided by healthy coral growth. Ecological and economic consequences of declining topographic complexity are likely to be substantial compared with selective effects of coral loss but both coral cover and topographic complexity must be recognised as a critical component of habitat structure and managed accordingly. Urgent action on the fundamental causes of climate change and appropriate management of critical elements of habitat structure (coral cover and topographic complexity) are key to ensuring long-term persistence of coral-reef fishes.
TL;DR: The Bodipy-Farbstoffe as discussed by the authors is an organischen elektronische materialien and farbstoffse, which were entwickelt für the aufstrebende Nanotechnologie.
Abstract: Organische Luminophore wurden lange nur in biologischen Markierungsverfahren und bestimmten analytischen Nachweisen angewendet, doch in jungster Zeit werden auch neuartige organische elektronische Materialien und Farbstoffe fur die aufstrebende Nanotechnologie entwickelt. Unter vielen verschiedenartigen Fluoreszenzfarbstoffen erwiesen sich dabei die Bodipy-Farbstoffe, die zunachst als Lumineszenzmarker und Laserfarbstoffe entwickelt worden waren, als besonders geeignet. Dieser “kleinen Schwester des Porphyrins” scheinen grose Perspektiven offenzustehen.
TL;DR: Clarithromycin therapy can modulate IL-8 levels and neutrophil accumulation and activation in the airways of patients with refractory asthma and may be an important additional therapy that could be used to reduce noneosinophilic airway inflammation, particularly neutrophilic inflammation, in asthma.
Abstract: Rationale: Patients with refractory asthma have persistent symptoms despite maximal treatment with inhaled corticosteroids and long-acting bronchodilators. The availability of add-on therapies is limited, and effective add-on therapies that target noneosinophilic airway inflammation are needed. Macrolide antibiotics, such as clarithromycin, have in vitro efficacy against IL-8 and neutrophils, key inflammatory mediators in noneosinophilic asthma.Objectives: To determine the efficacy of clarithromycin in patients with severe refractory asthma and specifically in a subgroup of patients with noneosinophilic asthma.Methods: Subjects with severe refractory asthma (n = 45) were randomized to receive clarithromycin (500 mg twice daily) or placebo for 8 weeks.Measurements and Main Results: The primary outcome for this study was sputum IL-8 concentration. Other inflammatory outcomes assessed included sputum neutrophil numbers and concentrations of neutrophil elastase and matrix metalloproteinase (MMP)-9. Clinical o...
TL;DR: O Oral LP can be a source of severe morbidity and has a small potential to be malignant, but biopsy is recommended to confirm the diagnosis and to exclude dysplasia and malignancy.
Abstract: Lichen planus (LP) is a common disorder in which auto-cytotoxic T lymphocytes trigger apoptosis of epithelial cells leading to chronic inflammation. Oral LP (OLP) can be a source of severe morbidity and has a small potential to be malignant. The diagnosis of OLP can be made from the clinical features if they are sufficiently characteristic, particularly if typical skin or other lesions are present, but biopsy is recommended to confirm the diagnosis and to exclude dysplasia and malignancy. OLP is treated with anti-inflammatory agents, mainly the topical corticosteroids, but newer agents and techniques are becoming available.
TL;DR: Developing a high perceived sports competence through object control skill development in childhood is important for both boys and girls in determining adolescent physical activity participation and fitness.
Abstract: The purpose of this paper was to investigate whether perceived sports competence mediates the relationship between childhood motor skill proficiency and subsequent adolescent physical activity and fitness. In 2000, children's motor skill proficiency was assessed as part of a school-based physical activity intervention. In 2006/07, participants were followed up as part of the Physical Activity and Skills Study and completed assessments for perceived sports competence (Physical Self-Perception Profile), physical activity (Adolescent Physical Activity Recall Questionnaire) and cardiorespiratory fitness (Multistage Fitness Test). Structural equation modelling techniques were used to determine whether perceived sports competence mediated between childhood object control skill proficiency (composite score of kick, catch and overhand throw), and subsequent adolescent self-reported time in moderate-to-vigorous physical activity and cardiorespiratory fitness. Of 928 original intervention participants, 481 were located in 28 schools and 276 (57%) were assessed with at least one follow-up measure. Slightly more than half were female (52.4%) with a mean age of 16.4 years (range 14.2 to 18.3 yrs). Relevant assessments were completed by 250 (90.6%) students for the Physical Activity Model and 227 (82.3%) for the Fitness Model. Both hypothesised mediation models had a good fit to the observed data, with the Physical Activity Model accounting for 18% (R2 = 0.18) of physical activity variance and the Fitness Model accounting for 30% (R2 = 0.30) of fitness variance. Sex did not act as a moderator in either model. Developing a high perceived sports competence through object control skill development in childhood is important for both boys and girls in determining adolescent physical activity participation and fitness. Our findings highlight the need for interventions to target and improve the perceived sports competence of youth.
TL;DR: It is proposed that reconceptualising nursing students' clinical learning experiences through a 'lens of belongingness' provides a new perspective and reveals yet unexplored insights.
TL;DR: Self-efficacy was the most commonly assessed mediator in youth interventions and there was strong support for its role in mediating the relation between theory-based interventions and physical activity.
TL;DR: In this article, a modified predictive current control strategy is presented, which allows one to have control over the spectrum of the load current using a model of the system to predict the behavior of the current for each possible voltage vector generated by the inverter.
Abstract: This paper presents a modified predictive current control strategy which allows one to have control over the spectrum of the load current. The proposed method uses a model of the system to predict the behavior of the current for each possible voltage vector generated by the inverter. For that purpose, at each sampling interval, signal predictions are evaluated using a cost function that quantifies the desired system behavior. The cost function used in this work evaluates the filtered error of the load currents. The inclusion of a filter for the load error allows one to manipulate current spectra. Thus, by designing this filter appropriately, the load spectrum can be shaped. The performance of the proposed control strategy is verified by simulation and experimental results.
TL;DR: Higher dietary lutein and zeaxanthin intake reduced the risk of long-term incident AMD and confirmed the Age-Related Eye Disease Study finding of protective influences from zinc against AMD.
TL;DR: To this knowledge, this is the first time that empirical data on foraging distances and forage availability, at this resolution and scale, have been collected and combined for bumblebees.
Abstract: 1. Foraging range is a key aspect of the ecology of 'central place foragers'. Estimating how far bees fly under different circumstances is essential for predicting colony success, and for estimating bee-mediated gene flow between plant populations. It is likely to be strongly influenced by forage distribution, something that is hard to quantify in all but the simplest landscapes; and theories of foraging distance tend to assume a homogeneous forage distribution. 2. We quantified the distribution of bumblebee Bombus terrestris L. foragers away from experimentally positioned colonies, in an agricultural landscape, using two methods. We mass-marked foragers as they left the colony, and analysed pollen from foragers returning to the colonies. The data were set within the context of the 'forage landscape': a map of the spatial distribution of forage as determined from remote-sensed data. To our knowledge, this is the first time that empirical data on foraging distances and forage availability, at this resolution and scale, have been collected and combined for bumblebees. 3. The bees foraged at least 1.5 km from their colonies, and the proportion of foragers flying to one field declined, approximately linearly, with radial distance. In this landscape there was great variation in forage availability within 500 m of colonies but little variation beyond 1 km, regardless of colony location. 4. The scale of B. terrestris foraging was large enough to buffer against effects of forage patch and flowering crop heterogeneity, but bee species with shorter foraging ranges may experience highly variable colony success according to location.
TL;DR: There was some evidence that the accuracy of self-assessment can be enhanced by feedback, particularly video and verbal, and by providing explicit assessment criteria and benchmarking guidance, which raises questions about assumed reliability and validity of this ‘gold standard’.
Abstract: Review date: Literature search January 1990 to February 2005 (with update February 2006). Analysis completed January 2007. Background: Health professionals are increasingly expected to identify their own learning needs through a process of ongoing self-assessment. Self-assessment is integral to many appraisal systems and has been espoused as an important aspect of personal professional behaviour by several regulatory bodies and those developing learning outcomes for clinical students. In this review we considered the evidence base on self-assessment since Gordon’s comprehensive review in 1991. The overall aim of the present review was to determine whether specific methods of self-assessment lead to change in learning behaviour or clinical practice. Specific objectives sought evidence for effectiveness of self-assessment interventions to: a. improve perception of learning needs; b. promote change in learning activity; c. improve clinical practice; d. improve patient outcomes. Methods: The methods for this review were developed and refined in a series of workshops with input from an expert BEME systematic reviewer, and followed BEME guidance. Databases searched included Medline, CINAHL, BNI, Embase, EBM Collection, Psychlit, HMIC, ERIC, BEI, TIMElit and RDRB. Papers addressing self-assessment in all professions in clinical practice were included, covering under- and post-graduate education, with outcomes classified using an extended version of Kirkpatrick’s hierarchy. In addition we included outcome measures of accuracy of self-assessment and factors influencing it. 5,798 papers were retrieved, 194 abstracts were identified as potentially relevant and 103 papers coded independently by pairs using an electronic coding sheet adapted from the standard BEME form. This total included 12 papers identified by hand-searches, grey literature, cited references and updating. The identification of a further 12 papers during the writing-up process resulted in a total of 77 papers for final analysis. Results: Although a large number of papers resulted from our original search only a small proportion of these were of sufficient academic rigour to be included in our review. The majority of these focused on judging the accuracy of self-assessment against some external standard, which raises questions about assumed reliability and validity of this ‘gold standard’. No papers were found which satisfied Kirkpatrick’s hierarchy above level 2, or which looked at the association between self-assessment and resulting changes in either clinical practice or patient outcomes. Thus our review was largely unable to answer the specific research questions and provide a solid evidence base for effective self-assessment. Despite this, there was some evidence that the accuracy of self-assessment can be enhanced by feedback, particularly video and verbal, and by providing explicit assessment criteria and benchmarking guidance. There was also some evidence that the least competent are also the least able to self-assess accurately. Our review recommends that these areas merit future systematic research to further our understanding of self-assessment. Conclusion: As in other BEME reviews, the methodological issues emerging from this review indicate a need for more rigorous study designs. In addition, it highlights the need to consider the potential for combining qualitative and quantitative data to further our understanding of how self-assessment can improve learning and professional clinical practice.
TL;DR: This protocol has advantages over other procedures in terms of speed and by producing relatively homogeneous synaptosomes, minimizing the presence of synaptic and glial plasma membranes and extrasynaptosomal mitochondria.
Abstract: Homogenization of fresh brain tissue in isotonic medium shears plasma membranes causing nerve terminals to become separated from their axons and postsynaptic connections. The nerve terminal membranes then reseal to form synaptosomes. The discontinuous Percoll gradient procedure described here is designed to isolate synaptosomes from brain homogenates in the minimum time to allow functional experiments to be performed. Synaptosomes are isolated using a medium-speed centrifuge, while maintaining isotonic conditions and minimizing mechanically damaging resuspension steps. This protocol has advantages over other procedures in terms of speed and by producing relatively homogeneous synaptosomes, minimizing the presence of synaptic and glial plasma membranes and extrasynaptosomal mitochondria. The purified synaptosomes are viable and take up and release neurotransmitters very efficiently. A typical yield of synaptosomes is between 2.5 and 4 mg of synaptosomal protein per gram rat brain. The procedure takes approximately 1 h from homogenization of the brain until collection of the synaptosomal suspension from the Percoll gradient.
TL;DR: Some of the methods for replacing the convolutions, which have been reported in different areas of analysis of marine systems: hydrodynamics, wave energy conversion, and motion control systems are revisited, and a model for the response in the vertical plane of a modern containership is considered.
TL;DR: Analysis of global microRNA expression in postmortem cortical grey matter from the superior temporal gyrus revealed significant up-regulation of miR-181b expression in schizophrenia.
Abstract: Analysis of global microRNA (miRNA) expression in postmortem cortical grey matter from the superior temporal gyrus, revealed significant up-regulation of miR-181b expression in schizophrenia. This finding was supported by quantitative real-time RT-PCR analysis of miRNA expression in a cohort of 21 matched pairs of schizophrenia and non-psychiatric controls. The implications of this finding are substantial, as this miRNA is predicted to regulate many target genes with potential significance to the development of schizophrenia. They include the calcium sensor gene visinin-like 1 (VSNL1) and the ionotropic AMPA glutamate receptor subunit (GRIA2), which were found to be down-regulated in the same cortical tissue from the schizophrenia group. Both of these genes were also suppressed in miR-181b transfected cells and shown to contain functional miR-181b miRNA recognition elements by reporter gene assay. This study suggests altered miRNA levels could be a significant factor in the dysregulation of cortical gene expression in schizophrenia.
TL;DR: In this paper, the authors test for the Random Walk Hypothesis (RWH) for seven stock markets in Gulf Cooperation Council (GCC) countries, and determine the effect of the correction for thin trading.