Payload IVA training and simulation

The development of a training program for the intravehicular operation of space shuttle payloads is discussed. The priorities for the program are compliance with established training standards, and accommodating changes. Simulation devices are also reviewed

Wirkung von Oberflächenladungen auf Zellen - Beobachtungen in der Nanodimension

Living organisms and in particular cells actively structure their inner world in the nano-dimension. Not only organelles are formed by the cells, but also their direct environment, the extracellular matrix. Recent studies show that electrical potentials are similarly important in the process of adhesion and directed migration. Nanostructured charge patterns may also influence the interactions between cells, tissues and implants used in therapy. Even small differences in the structure of charged molecules can already change the behaviour of cells drastically. Inside the cell, furthermore, very small topographic features are decisive: In ion channels, dimensions of 1/100 nm are essential for their function. Such precise structures are nowadays still a technical challenge. When modelling such cellular “electronics” using chip technology, we can learn a lot from nature’s tricks in cell physiology.Lebende Organismen und insbesondere die einzelnen Zellen selbst sind Meister in der aktiven Strukturierung auf Nanoebene. So bilden die Zellen nicht nur ihr reichhaltiges „Innenleben“ in dieser Dimension, sondern strukturieren auch ihre direkte Umgebung, den extrazellulären Bereich. Bei der Haftung und gerichteten Bewegung der Zellen scheinen nach neueren Befunden auch elektrische Potenziale und Oberflächenladungen mit Mustern bis „hinab“ auf die Nanoebene eine Rolle zu spielen. Nanostrukturierte Muster von Ladungen können so auch die Wechselwirkung von Zellen und Geweben mit Implantaten beeinflussen. Diese Beobachtungen führen wieder zurück zu den Zellen selbst, die zum Beispiel im Falle von Ionenkanälen mit hundertstel Nanometer Genauigkeit Topographie und Potenziale kontrollieren. Solche Strukturen könnten zukünftig auch über Chiptechnologie modelliert werden – eine Chance, von der Natur zu lernen und dies technisch umzusetzen

Local Calcium Elevation and Cell Elongation Initiate Guided Motility in Electrically Stimulated Osteoblast-Like Cells

BACKGROUND: Investigation of the mechanisms of guided cell migration can contribute to our understanding of many crucial biological processes, such as development and regeneration. Endogenous and exogenous direct current electric fields (dcEF) are known to induce directional cell migration, however the initial cellular responses to electrical stimulation are poorly understood. Ion fluxes, besides regulating intracellular homeostasis, have been implicated in many biological events, including regeneration. Therefore understanding intracellular ion kinetics during EF-directed cell migration can provide useful information for development and regeneration. METHODOLOGY/PRINCIPAL FINDINGS: We analyzed the initial events during migration of two osteogenic cell types, rat calvarial and human SaOS-2 cells, exposed to strong (10-15 V/cm) and weak (< or = 5 V/cm) dcEFs. Cell elongation and perpendicular orientation to the EF vector occurred in a time- and voltage-dependent manner. Calvarial osteoblasts migrated to the cathode as they formed new filopodia or lamellipodia and reorganized their cytoskeleton on the cathodal side. SaOS-2 cells showed similar responses except towards the anode. Strong dcEFs triggered a rapid increase in intracellular calcium levels, whereas a steady state level of intracellular calcium was observed in weaker fields. Interestingly, we found that dcEF-induced intracellular calcium elevation was initiated with a local rise on opposite sides in calvarial and SaOS-2 cells, which may explain their preferred directionality. In calcium-free conditions, dcEFs induced neither intracellular calcium elevation nor directed migration, indicating an important role for calcium ions. Blocking studies using cadmium chloride revealed that voltage-gated calcium channels (VGCCs) are involved in dcEF-induced intracellular calcium elevation. CONCLUSION/SIGNIFICANCE: Taken together, these data form a time scale of the morphological and physiological rearrangements underlying EF-guided migration of osteoblast-like cell types and reveal a requirement for calcium in these reactions. We show for the first time here that dcEFs trigger different patterns of intracellular calcium elevation and positional shifting in osteogenic cell types that migrate in opposite directions

Policies and practices of SHEA Research Network hospitals during the COVID-19 pandemic

To understand hospital policies and practices as the COVID-19 pandemic accelerated, the Society for Healthcare Epidemiology of America (SHEA) conducted a survey through the SHEA Research Network (SRN). The survey assessed policies and practices around the optimization of personal protection equipment (PPE), testing, healthcare personnel policies, visitors of COVID-19 patients in relation to procedures, and types of patients. Overall, 69 individual healthcare facilities responded in the United States and internationally, for a 73% response rate

Urban agriculture as a keystone contribution towards securing sustainable and healthy development for cities in the future

esearch and practice during the last 20 years has shown that urban agriculture can contribute to minimising the effects of climate change by, at the same time, improving quality of life in urban areas. In order to do so most effectively, land use and spatial planning are crucial so as to obtain and maintain a supportive green infrastructure and to secure citizens' healthy living conditions. As people today trend more towards living in green and sustainable city centres that can offer fresh and locally produced food, cities become again places for growing food. The scope of urban agriculture thereby is to establish food production sites within the city's sphere; for example, through building-integrated agriculture including concepts such as aquaponics, indoor agriculture, vertical farming, rooftop production, edible walls, as well as through urban farms, edible landscapes, school gardens and community gardens. Embedded in changing urban food systems, the contribution of urban agriculture to creating sustainable and climate-friendly cities is pivotal as it has the capacity to integrate other resource streams such as water, waste and energy. This article describes some of the current aspects of the circular city debate where urban agriculture is pushing forward the development of material and resource cycling in cities.European Cooperation in Science and Technology (COST): CA17133; EU Horizon 2020 Programmeinfo:eu-repo/semantics/publishedVersio

Effect of Radiologists’ Diagnostic Work-up Volume on Interpretive Performance

We found that radiologists with a higher annual volume of work-ups for recalled screening mammograms they initially interpreted had consistently higher screening sensitivity and cancer detection rates; however, these performance improvements were accompanied by higher false-positive rates

Productive osseous changes about the wrist in rheumatoid arthritis

Radiographs of 225 consecutive patients with adult-form rheumatoid arthritis were examined for evidence of productive osseous changes about the wrist. The prevalence of new bone on the ulnar styloid was 10%. This form of new bone is probably due to overlying chronic tenosynovitis. A collar of new bone around the ulnar head is a result of degenerative change in the distal radioulnar joint. In general, productive osseous changes in rheumatoid arthritis may represent inflammatory periosteal bone formation, osteophytosis, or contact remodeling. We found no evidence of an association between diffuse idiopathic skeletal hyperostosis and extensive productive osseous changes in patients with rheumatoid arthritis.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46784/1/256_2004_Article_BF00350967.pd

Informed Conditioning on Clinical Covariates Increases Power in Case-Control Association Studies

Genetic case-control association studies often include data on clinical covariates, such as body mass index (BMI), smoking status, or age, that may modify the underlying genetic risk of case or control samples. For example, in type 2 diabetes, odds ratios for established variants estimated from low–BMI cases are larger than those estimated from high–BMI cases. An unanswered question is how to use this information to maximize statistical power in case-control studies that ascertain individuals on the basis of phenotype (case-control ascertainment) or phenotype and clinical covariates (case-control-covariate ascertainment). While current approaches improve power in studies with random ascertainment, they often lose power under case-control ascertainment and fail to capture available power increases under case-control-covariate ascertainment. We show that an informed conditioning approach, based on the liability threshold model with parameters informed by external epidemiological information, fully accounts for disease prevalence and non-random ascertainment of phenotype as well as covariates and provides a substantial increase in power while maintaining a properly controlled false-positive rate. Our method outperforms standard case-control association tests with or without covariates, tests of gene x covariate interaction, and previously proposed tests for dealing with covariates in ascertained data, with especially large improvements in the case of case-control-covariate ascertainment. We investigate empirical case-control studies of type 2 diabetes, prostate cancer, lung cancer, breast cancer, rheumatoid arthritis, age-related macular degeneration, and end-stage kidney disease over a total of 89,726 samples. In these datasets, informed conditioning outperforms logistic regression for 115 of the 157 known associated variants investigated (P-value = 1×10−9). The improvement varied across diseases with a 16% median increase in χ2 test statistics and a commensurate increase in power. This suggests that applying our method to existing and future association studies of these diseases may identify novel disease loci

Aquaponics in the Built Environment

Aquaponics’ potential to transform urban food production has been documented in a rapid increase of academic research and public interest in the field. To translate this publicity into real-world impact, the creation of commercial farms and their relationship to the urban environment have to be further examined. This research has to bridge the gap between existing literature on growing system performance and urban metabolic flows by considering the built form of aquaponic farms. To assess the potential for urban integration of aquaponics, existing case studies are classified by the typology of their building enclosure, with the two main categories being greenhouses and indoor environments. This classification allows for some assumptions about the farms’ performance in their context, but a more in-depth life cycle assessment (LCA) is necessary to evaluate different configurations. The LCA approach is presented as a way to inventory design criteria and respective strategies which can influence the environmental impact of aquaponic systems in the context of urban built environments