Catalase-Containing Silica Particles as Ultrasound-Based Hydrogen Peroxide Sensors to Determine Infected From Noninfected Fluid Collections in Humans.

OBJECTIVE. Hydrogen peroxide (H2O2) plays a key role in neutrophil oxidative defense against infection. Catalase-containing silica nanoshells are nanoparticles that generate O2 microbubbles imaged with ultrasound in the presence of elevated H2O2. We aimed to determine whether ultrasound-detectable O2 microbubbles produced by catalase-containing silica nanoshells can determine whether fluid collections drained from patients are infected. SUBJECTS AND METHODS. During this HIPAA-compliant, institutional review board-approved study, 52 human fluid samples were collected from clinically required image-guided percutaneous drainage procedures. Catalase-containing silica nanoshells were added to the fluid samples during imaging in real time using a Sequoia-512 15L8-S linear transducer (Siemens Healthcare). Production of detectable microbubbles was graded subjectively as negative (noninfected) or positive (infected) with low, moderate, or high confidence by a single observer blinded to all clinical data. The truth standard was microbiology laboratory culture results. Performance characteristics including ROC curves were calculated. RESULTS. Microbubble detection to distinguish infected from noninfected fluids was 84% sensitive and 72% specific and offered negative and positive predictive values of 89% and 64%, respectively. The AUC was 0.79. Six of nine false-positive samples were peritoneal fluid collections that were all collected from patients with decompensated cirrhosis. CONCLUSION. The presence of elevated H2O2 indicated by microbubble formation in the presence of catalase-containing silica nanoshells is sensitive in distinguishing infected from noninfected fluids and offers a relatively high negative predictive value. False-positive cases may result from noninfectious oxidative stress. Catalase-containing silica nanoshells may constitute a novel point-of-care test performed at time of percutaneous drainage, potentially obviating placement of drains into otherwise sterile collections and minimizing risk of secondary infection or other complication

A Data-Virtualization System for Large Model Visualization

Interactive scientific visualizations are widely used for the visual exploration and examination of physical data resulting from measurements or simulations. Driven by technical advancements of data acquisition and simulation technologies, especially in the geo-scientific domain, large amounts of highly detailed subsurface data are generated. The oil and gas industry is particularly pushing such developments as hydrocarbon reservoirs are increasingly difficult to discover and exploit. Suitable visualization techniques are vital for the discovery of the reservoirs as well as their development and production. However, the ever-growing scale and complexity of geo-scientific data sets result in an expanding disparity between the size of the data and the capabilities of current computer systems with regard to limited memory and computing resources. In this thesis we present a unified out-of-core data-virtualization system supporting geo-scientific data sets consisting of multiple large seismic volumes and height-field surfaces, wherein each data set may exceed the size of the graphics memory or possibly even the main memory. Current data sets fall within the range of hundreds of gigabytes up to terabytes in size. Through the mutual utilization of memory and bandwidth resources by multiple data sets, our data-management system is able to share and balance limited system resources among different data sets. We employ multi-resolution methods based on hierarchical octree and quadtree data structures to generate level-of-detail working sets of the data stored in main memory and graphics memory for rendering. The working set generation in our system is based on a common feedback mechanism with inherent support for translucent geometric and volumetric data sets. This feedback mechanism collects information about required levels of detail during the rendering process and is capable of directly resolving data visibility without the application of any costly occlusion culling approaches. A central goal of the proposed out-of-core data management system is an effective virtualization of large data sets. Through an abstraction of the level-of-detail working sets, our system allows developers to work with extremely large data sets independent of their complex internal data representations and physical memory layouts. Based on this out-of-core data virtualization infrastructure, we present distinct rendering approaches for specific visualization problems of large geo-scientific data sets. We demonstrate the application of our data virtualization system and show how multi-resolution data can be treated exactly the same way as regular data sets during the rendering process. An efficient volume ray casting system is presented for the rendering of multiple arbitrarily overlapping multi-resolution volume data sets. Binary space-partitioning volume decomposition of the bounding boxes of the cube-shaped volumes is used to identify the overlapping and non-overlapping volume regions in order to optimize the rendering process. We further propose a ray casting-based rendering system for the visualization of geological subsurface models consisting of multiple very detailed height fields. The rendering of an entire stack of height-field surfaces is accomplished in a single rendering pass using a two-level acceleration structure, which combines a minimum-maximum quadtree for empty-space skipping and sorted lists of depth intervals to restrict ray intersection searches to relevant height fields and depth ranges. Ultimately, we present a unified rendering system for the visualization of entire geological models consisting of highly detailed stacked horizon surfaces and massive volume data. We demonstrate a single-pass ray casting approach facilitating correct visual interaction between distinct translucent model components, while increasing the rendering efficiency by reducing processing overhead of potentially invisible parts of the model. The combination of image-order rendering approaches and the level-of-detail feedback mechanism used by our out-of-core data-management system inherently accounts for occlusions of different data types without the application of costly culling techniques. The unified out-of-core data-management and virtualization infrastructure considerably facilitates the implementation of complex visualization systems. We demonstrate its applicability for the visualization of large geo-scientific data sets using output-sensitive rendering techniques. As a result, the magnitude and multitude of data sets that can be interactively visualized is significantly increased compared to existing approaches

One Minute Tips: Take Two! Student Perceptions of Videos Used for Information Literacy Instruction

Digital learning objects are all the rage, but what does the YouTube generation think? We will discuss student perceptions of videos used for information literacy instruction and methods for incorporating short videos into assessable learning activities

Ideal treatment timing of orthodontic anomalies—a German clinical S3 practice guideline

Purpose Ideal treatment timing in orthodontics is controversially discussed depending on the type and extent of the dysgnathia and malocclusion present, especially with regard to efficiency, patient burden and treatment efforts of early compared to regular or late treatment. This German clinical practice guideline aims to clarify, at which time points an orthodontic anomaly can be effectively treated and how treatment efficiency differs depending on treatment timing. Methods A systematic literature search was performed in various guideline databases and databases PROSPERO, MEDLINE (PubMed), Cochrane Library, Web of Science, ClinicalTrials.gov and the International Clinical Trials Registry Platform according to a predefined PICO (Population, Intervention, Comparison and Outcomes with added qualitative search terms) search algorithm and strategy. Appraisal of scientific evidence of the individual studies checked for eligibility was carried out according to SIGN (Scottish Intercollegiate Guidelines Network), AMSTAR II (Assessing the Methodological Quality of Systemic Reviews), and AXIS (Appraisal Tool to Assess the Quality of Cross-sectional Studies) tools. Only controlled studies with a high, acceptable or moderate quality (and thus an acceptable risk of bias) were considered. Results A total of 309 studies of over 11,000 sources screened were identified to be eligible for inclusion and critically appraised for study quality and risk-of-bias. No relevant guidelines relating to the aims of the present guideline were found. Elected delegates of in total 21 German scientific societies and organizations agreed upon a total of 19 evidence-based statements and recommendations based on a nominal consensus process. Conclusions Although most malocclusions can be effectively treated both in the early, late mixed, and permanent dentition, evidence suggests that therapy of a pronounced skeletal or dental class II anomaly can be started early to reduce the risk of dental anterior tooth trauma, whereas in a moderate class II anomaly, therapy can preferably be carried out before or during the pubertal growth peak. Therapy of a skeletal or dental class III anomaly should be started early, as this also reduces the need for later surgery to correct the anomaly. The treatment of a pronounced skeletal or dental transverse anomaly should be started early in the upper jaw in order to utilize the high adaptivity of the maxillary structures in young patients

A Novel Prokaryote-Type ECF/ABC Transporter Module in Chloroplast Metal Homeostasis

During evolution, chloroplasts, which originated by endosymbiosis of a prokaryotic ancestor of today's cyanobacteria with a eukaryotic host cell, were established as the site for photosynthesis. Therefore, chloroplast organelles are loaded with transition metals including iron, copper, and manganese, which are essential for photosynthetic electron transport due to their redox capacity. Although transport, storage, and cofactor-assembly of metal ions in chloroplasts are tightly controlled and crucial throughout plant growth and development, knowledge on the molecular nature of chloroplast metal-transport proteins is still fragmentary. Here, we characterized the soluble, ATP-binding ABC-transporter subunits ABCI10 and ABCI11 in Arabidopsis thaliana, which show similarities to components of prokaryotic, multisubunit ABC transporters. Both ABCI10 and ABCI11 proteins appear to be strongly attached to chloroplast-intrinsic membranes, most likely inner envelopes for ABCI10 and possibly plastoglobuli for ABCI11. Loss of ABCI10 and ABCI11 gene products in Arabidopsis leads to extremely dwarfed, albino plants showing impaired chloroplast biogenesis and deregulated metal homeostasis. Further, we identified the membrane-intrinsic protein ABCI12 as potential interaction partner for ABCI10 in the inner envelope. Our results suggest that ABCI12 inserts into the chloroplast inner envelope membrane most likely with five predicted a-helical transmembrane domains and represents the membrane-intrinsic subunit of a prokaryotic-type, energy-coupling factor (ECF) ABC-transporter complex. In bacteria, these multisubunit ECF importers are widely distributed for the uptake of nickel and cobalt metal ions as well as for import of vitamins and several other metabolites. Therefore, we propose that ABCI10 (as the ATPase A-subunit) and ABCI12 (as the membrane-intrinsic, energy-coupling T-subunit) are part of a novel, chloroplast envelope-localized, AAT energy-coupling module of a prokaryotic-type ECF transporter, most likely involved in metal ion uptake.11Nsciescopu

Strategy-adaptation memory training: predictors of older adults' training gains

AbstractOver the past decades, memory training interventions have been developed in an attempt to stabilize or enhance memory functioning in aging. Only recently has attention been paid to individual differences in training gains and consequently to predictors of such gains. The aim of the present study was to identify which specific cognitive mechanisms/processes or components of the intervention were responsible for the desired change and which individuals were more responsive to memory strategic training. Eighty-one older adults (aged 55 to 82) were involved in a four-session strategy-adaptation training based on a learner-oriented approach that has previously been found to be effective in improving memory performance in practiced and untrained tasks. Results showed that baseline performance in memory tasks predicted the gains in the practiced task. Baseline performance in memory tasks and other cognitive variables, such as working memory, processing speed, and verbal knowledge predicted transfer effects. Interestingly, we found that the magnitude of training gain on the associative memory practiced task predicted the gains in the transfer tasks, suggesting those who best implemented the targeted strategies during training realized greater transfer to other tasks. Our study shows that older adults with larger cognitive resources will benefit more from interventions focused on the generalization via active processes

"Even if the test result is negative, they should be able to tell us what is wrong with us": a qualitative study of patient expectations of rapid diagnostic tests for malaria.

BACKGROUND: The debate on rapid diagnostic tests (RDTs) for malaria has begun to shift from whether RDTs should be used, to how and under what circumstances their use can be optimized. This has increased the need for a better understanding of the complexities surrounding the role of RDTs in appropriate treatment of fever. Studies have focused on clinician practices, but few have sought to understand patient perspectives, beyond notions of acceptability. METHODS: This qualitative study aimed to explore patient and caregiver perceptions and experiences of RDTs following a trial to assess the introduction of the tests into routine clinical care at four health facilities in one district in Ghana. Six focus group discussions and one in-depth interview were carried out with those who had received an RDT with a negative test result. RESULTS: Patients had high expectations of RDTs. They welcomed the tests as aiding clinical diagnoses and as tools that could communicate their problem better than they could, verbally. However, respondents also believed the tests could identify any cause of illness, beyond malaria. Experiences of patients suggested that RDTs were adopted into an existing system where patients are both physically and intellectually removed from diagnostic processes and where clinicians retain authority that supersedes tests and their results. In this situation, patients did not feel able to articulate a demand for test-driven diagnosis. CONCLUSIONS: Improvements in communication between the health worker and patient, particularly to explain the capabilities of the test and management of RDT negative cases, may both manage patient expectations and promote patient demand for test-driven diagnoses

Recycling Argon through Metamorphic Reactions: the Record in Symplectites

The 40Ar/39Ar ages of metamorphic micas that crystallized at high temperatures are commonly interpreted as cooling ages, with grains considered to have lost 40Ar via thermally-driven diffusion into the grain boundary network. Recently reported laser-ablation data suggest that the spatial distribution of Ar in metamorphic micas does not always conform to the patterns predicted by diffusion theory and that despite high metamorphic temperatures, argon was not removed efficiently from the local system during metamorphic evolution. In the Western Gneiss Region (WGR), Norway, felsic gneisses preserve microtextural evidence for the breakdown of phengite to biotite and plagioclase symplectites during near isothermal decompression from c. 20–25 to c. 8–12 kbar at ~700°C. These samples provide an ideal natural laboratory to assess whether the complete replacement of one K-bearing mineral by another at high temperatures completely ‘resets’ the Ar clock, or whether there is some inheritance of 40Ar in the neo-crystallized phase. The timing of the high-temperature portion of the WGR metamorphic cycle has been well constrained in previous studies. However, the timing of cooling following the overprint is still much debated. In-situ laser ablation spot dating in phengite, biotite-plagioclase symplectites and coarser, texturally later biotite yielded 40Ar/39Ar ages that span much of the metamorphic cycle. Together these data show that despite residence at temperatures of ~700°C, Ar is not completely removed by diffusive loss or during metamorphic recrystallization. Instead, Ar released during phengite breakdown appears to be partially reincorporated into the newly crystallizing biotite and plagioclase (or is trapped in fluid inclusions in those phases) within a close system. Our data show that the microtextural and petrographic evolution of the sample being dated provides a critical framework in which local 40Ar recycling can be tracked, thus potentially allowing 40Ar/39Ar dates to be linked more accurately to metamorphic history

Prednisolone or tetracosactide depot for infantile epileptic spasms syndrome? A prospective analysis of data embedded within two randomised controlled trials

OBJECTIVE: To report a prospectively planned analysis of two randomised controlled trials with embedded comparisons of prednisolone versus tetracosactide depot for the treatment of infantile epileptic spasms syndrome (IESS). METHODS: Individual patient data from patients randomly allocated to prednisolone or tetracosactide depot were analysed from two trials (UKISS, ICISS). The comparison was embedded within trials in which some patients also received vigabatrin but only patients receiving monotherapy with randomly allocated hormonal treatments are included in this analysis. The main outcome was cessation of spasms (Days 13-14 after randomisation). Lead time to treatment and underlying aetiology were taken into account. Cessation of spasms on Days 14-42 inclusive, electroclinical response (EEG Day 14), plus developmental and epilepsy outcomes (at 14 months in UKISS and 18 months in ICISS) are also reported. Minimum treatment was prednisolone 40 mg per day for two weeks or tetracosactide depot 0·5 mg IM on alternate days for two weeks, all followed by a reducing dose of prednisolone over two weeks. RESULTS: 126 infants were included in this study. On tetracosactide depot, 47 of 62 (76%) were free of spasms on Days 13-14 compared to 43 of 64 (67%) on prednisolone (difference 9%, 95% CI -7·2% to +25·2%, chi square 1·15, p = 0·28). For Day 14-42 cessation of spasms, on tetracosactide depot, 41 of 61 (67%) were free of spasms compared to 35 of 62 (56%) on prednisolone (difference 11%, 95% CI -6·4% to +28·4%, chi square 1·51, p = 0·22). There was no significant difference in mean VABS score between infants who received prednisolone compared with those who received tetracosactide depot (74·8 (SD 18·3) versus 78·0 (SD 20·2) t = -0·91 p = 0·36). The proportion with ongoing epilepsy at the time of developmental assessment was 20 of 61 (33%) in the tetracosactide group compared with 26 out of 63 (41%) in the prednisolone group (difference 8%, 95% CI -9·2% to +25·2%, Chi [2] 0·95, p = 0·33). SIGNIFICANCE: With hormone monotherapy, either prednisolone or tetracosactide depot may be recommended for infantile epileptic spasms syndrome