2,746 research outputs found
Preparatory space experiments for development of a CELSS
The goal of Closed Ecological Life Support System (CELSS) studies is to examine the effects of microgravity on yield and quality of plant products and on the interactions between irradiance and crop area. Measuring yield and quality of crops as a function of irradiance in microgravity is virtually unique to the CELSS program, as is the emphasis on canopies rather than individual plants. The first step for space experiments is to develop a relatively stress free environment for plant growth, something that has so far never been achieved. High light levels are essential, and there must be time enough to complete a significant portion of the life cycle. Optimal atmosphere and nutrients must be provided. Such responses as germination, orientation of roots and shoots, photosynthesis and respiration, floral initiation and development, and seed maturation and viability will be studied
Insulin/Insulin-like growth factors in cancer: new roles for the aryl hydrocarbon receptor, tumor resistance mechanisms, and new blocking strategies
The insulin-like growth factor 1 receptor (IGF1R) and the insulin receptor (IR) are receptor tyrosine kinases that are expressed in cancer cells.The results of different studies indicate that tumor proliferation and survival is dependent on the IGF1R and IR, and that their inhibition leads to reductions in proliferation and increases in cell death. Molecular targeting therapies that have been used in solid tumors include anti-IGF1R antibodies, anti-IGF1/IGF2 antibodies, and small molecule inhibitors that suppress IGF1R and IR kinase activity. New advances in the molecular basis of anti-IGF1R blocking antibodies reveal they are biased agonists and promote the binding of IGF1 to integrin b3 receptors in some cancer cells. Our recent reports indicate that pharmacological aryl hydrocarbon receptor (AHR) ligands inhibit breast cancer cell responses to IGFs, suggesting that targeting AHR may have benefit in cancers whose proliferation and survival are dependent on insulin/IGF signaling. Novel aspects of IGF1R/IR in cancer, such as biased agonism, integrin b3 signaling, AHR, and new therapeutic targeting strategies will be discussed
Place and identity: networks of Neolithic communities in Central Europe
The multi-layered and multi-scalar nature of the term ācommunityā makes it a useful tool for both particularistic studies and cross-cultural comparisons, connecting scales of community to regional scales of settlement, exchange and mobility. This paper explores three general themes of community: community as place, as identity and as network. A case study of Neolithic communities in eastern Hungary and Lower Austria demonstrates a spatial and geoarchaeological approach to understanding the relational aspects of places, networks and identity to develop a social archaeology of communities.VeÄplasten in veÄnivojski izraz āskupnostā predstavlja uporabno orodje tako za partikularistiÄne Å”tudije kot za medkulturne primerjave, saj povezuje obseg skupnosti z regionalnimi poselitvenimi vzorci, menjavo in mobilnostjo. V Älanku prouÄujemo tri glavne teme: skupnost kot kraj, skupnost kot identiteto in skupnost kot omrežje. S Å”tudijskim primerom neolitskih skupnosti na obmoÄju vzhodne Madžarske in Spodnje Avstrijske bomo prikazali vidike odnosov krajev, omrežij in identitet ter razvili družbeno arheologijo skupnosti
Archaeology at the Danube using non-invasive ground and aerial prospection methods to document prehistoric settlement traces at the Bisamberg near Vienna, Austria
To link prehistoric settlement activities with a modern mapping of existing monuments on the site, non-invasive aerial and terrestrial prospection methods are used. The LiDAR data catches the course of the presumed prehistoric rampart. The geomagnetic measurements display, among other things, the course of a 250 m long prehistoric ditch. Furthermore, ERT measurements reveal the rampartās inner construction
Researching and learning together : inter-institutional collaboration as a strategy for capacity building. Reflections based on the evaluations of the Welsh Education Research Network. BERA symposium paper.
Studies on maximum yield of wheat for the controlled environments of space
The economic feasibility of using food-producing crop plants in a closed ecological Life-Support System (CELSS) will ultimately depend on the energy and area (or volume) required to provide the nutritional requirements for each person. Energy and area requirements are, to some extent, inversely related; that is, an increased energy input results in a decreased area requirement and vice versa. A major goal of the research effort was to determine the controlled-environment good-production efficiency of wheat per unit area, per unit time, and per unit energy input
The nature and role of experiential knowledge for environmental conservation
Understanding the nature and role of experiential knowledge for environmental conservation is a necessary step towards understanding if it should be used and how it might be applied with other types of knowledge in an evidence-based approach. This paper describes the nature of experiential and expert knowledge. It then discusses the role of experiential knowledge as a complement to scientific knowledge and explains the interplay between experiential knowledge with conservation research and practice using a simple conceptual model of how individuals learn. There are five main conclusions: (1) because experiential knowledge will always play a role in decision-making, enhancing ability to learn from experiences (including research) will have a significant influence on the effectiveness of conservation outcomes; (2) while experiential knowledge is qualitatively very different from quantitative information, both are important and complementary; (3) some experiential knowledge can be expressed quantitatively, but experiential knowledge can be difficult to isolate as single facts or propositions and qualitative methods will therefore often be required to elicit experiential knowledge; (4) because each person's expertise is unique, when using experiential knowledge the extent of a person's experience and its relevance to a particular problem need to be specified; and (5) as with any form of knowledge, there are limitations to that derived from personal experience. Synthesis and communication of research is therefore essential to help prevent erroneous thinking and, where possible, experiential knowledge should be used in conjunction with other types of information to guide conservation actions.Publisher PDFPeer reviewe
Computed tomography measures of nutrition in patients with end-stage liver disease provide a novel approach to characterize deficits
Aim
Patients with cirrhosis and end-stage liver disease (ESLD) develop severe nutrition deficits that impact on morbidity and mortality. Laboratory measures of nutrition fail to fully assess clinical deficits in muscle mass and fat stores. This study employs computed tomography imaging to assess muscle mass and subcutaneous and visceral fat stores in patients with ESLD.
Methods
This 1:1 case-control study design compares ESLD patients with healthy controls. Study patients were selected from a database of ESLD patients using a stratified method to assure a representative sample based on age, body mass index (BMI), gender, and model for end-stage liver disease score (MELD). Control patients were trauma patients with a low injury severity score (<10) who had a CT scan during evaluation. Cases and controls were matched for age +/- 5 years, gender, and BMI +/- 2.
Results
There were 90 subjects and 90 controls. ESLD patients had lower albumin levels (p<0.001), but similar total protein levels (p=0.72). ESLD patients had a deficit in muscle mass (-19%, p<0.001) and visceral fat (-13%, p<0.001), but similar subcutaneous fat (-1%, p=0.35). ESLD patients at highest risk for sarcopenia included those over age 60, BMI< 25.0, and female gender. We found degree of sarcopenia to be independent of MELD score.
Conclusions
These results support previous research demonstrating substantial nutrition deficits in ESLD patients that are not adequately measured by laboratory testing. Patients with ESLD have significant deficits of muscle and visceral fat stores, but a similar amount of subcutaneous fat
Removal of terrestrial DOC in aquatic ecosystems of a temperate river network
Surface waters play a potentially important role in the global carbon balance. Dissolved organic carbon (DOC) fluxes are a major transfer of terrestrial carbon to river systems, and the fate of DOC in aquatic systems is poorly constrained. We used a unique combination of spatially distributed sampling of three DOC fractions throughout a river network and modeling to quantify the net removal of terrestrial DOC during a summer base flow period. We found that aquatic reactivity of terrestrial DOC leading to net loss is low, closer to conservative chloride than to reactive nitrogen. Net removal occurred mainly from the hydrophobic organic acid fraction, while hydrophilic and transphilic acids showed no net change, indicating that partitioning of bulk DOC into different fractions is critical for understanding terrestrial DOC removal. These findings suggest that river systems may have only a modest ability to alter the amounts of terrestrial DOC delivered to coastal zones
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