Development of More Efficacious {Tc}-99m Organ Imaging Agents for Use in Nuclear Medicine by Analytical Characterization of Radiopharmaceuticals. Annual Technical Progress Report, September 1, 1992--August 31, 1993

This research program is detailed at development of more efficacious technetium-99m radiopharmaceuticals for use as imaging agents in diagnostic nuclear medicine. We seek to isolate and develop distinct site imaging agents to provide diagnostic information concerning a given pathological condition. Analytical techniques are being developed to enable complete analysis of radiopharmaceutical preparations so that individual complexes can be characterized with respect to imaging efficacy and to enable a radiopharmaceutical to be monitored after injection into a test animal to determine the species that actually accumulates in an organ to provide the image. Administration of the isolated, single most effective imaging complex, rather than a mixture of technetium-containing complexes, wi-11 minimize radiation exposure to the patient and maximize diagnostic information available to the clinician. This report specifically describes the development of capillary electrophoresis (CE) for characterizating diphosphonate skeletal imaging agents. Advances in the development of electrochemical and fiber optic sensors for Tc and Re imaging agents are described. These sensors will ultimately be capable of monitoring a specific chemical state of an imaging agent in vivo after injection into a test animal by implantation in the organ of interest

Development of More Efficacious Tc-99m Organ Imaging Agents for Use in Nuclear Medicine by Analytical Characterization of Radiopharmaceutical Mixtures

The long-range objective of this research program is the development of more efficacious technetium-99m radiopharmaceuticals for use as imaging agents in diagnostic nuclear medicine. We seek to isolate and develop distinct site imaging agents, each of which has properties optimized to provide diagnostic information concerning a given pathological condition. The specific objectives during the period (9/1/89 to 8/31/92) include: (1) Development of strategies for improving yields of specific Tc-diphosphonate complexes with optimum imaging properties; (2) Development of electrodes for rapid in situ electrochemical generation of skeletal imaging agents; (3) Development of electrochemical sensors for {Tc} and Re imaging agents; (4) Characterization of stable {Tc}- and Re-diphosphonate complexes obtainable in high yield by structural studies with techniques such as NMR, EXAFS, and Raman spectroscopy; (5) Development of improved separation techniques for the characterization of diphosphonate skeletal imaging agents; (6) Evaluation of the effect of the biological milieu on {Tc}-diphosphonate complexes; and (7) Electrochemical studies of technetium and rhenium complexes synthesized by Professor Deutsch's research group for heart and brain imaging

PII: S 0 0 4 0 -6 0 9 0 Ž 0 3 . 0 0 0 2 9 -4 In situ measurements of sensor film dynamics by spectroscopic ellipsometry. Demonstration of back-side measurements and the etching of indium tin oxide

Abstract A new liquid flow cell design for in situ ellipsometric measurements on transparent multilayer samples using variable angle spectroscopic ellipsometry is presented. In this cell, films made on transparent substrates are in direct contact with liquid solution. Ellipsometry measurements are made through the transparent substrate, that is, from the back-side relative to the incident light so that films are in continuous contact with the liquid. This cell is not limited to just one angle of incidence of light allowing the films to be characterized at several angles before, during and after liquid contact. The spectral range of measurements is limited only by absorption of light in the underlying transparent substrate and not by the liquid solution that the film is in contact with. As a demonstration, we have measured and analyzed the dynamics of an indium tin oxide film on glass undergoing acid etching. Data from this in situ experiment were successfully modeled and the ITO layer thickness decreased uniformly during the etching process with an average etch rate of 0.23 nmymin

Nutrient Availability in Tropical Rain Forests: The Paradigm of Phosphorus Limitation

Abstract A long-standing paradigm in tropical ecology is that phosphorus (P) availability limits the productivity of most lowland forests, with the largest pool of plant-available P resident in biomass. Evidence that P limits components of productivity is particularly strong for sites in Panama and the Amazon basin. Analyses of forest communities in Panama also show that tree species distributions are strongly affected by P availability at the regional scale, but that their local distributions in a single site on Barro Colorado Island (BCI) are as frequently correlated with base cations as with P. Traits associated with species sensitivity to P availability require more detailed exploration, but appear to show little similarity with those associated with N limitation in temperate forests. Recent research indicates that a large fraction of P in tropical forests exists as organic and microbial P in the soil; plant adaptations to access organic P, including the synthesis of phosphatase enzymes, likely represent critical adaptations to low P environments. Plants also cope with low P availability through increases in P use-efficiency resulting from increased retention time of P in biomass and decreased tissue P concentration. Although foliar P responds strongly to P addition, we show here that foliar P and N:P are highly variable within communities, and at BCI correlate with regional species distributional affinity for P. An improved understanding of P limitation, and in particular the plasticity of responses to P availability, will be critical to predicting community and ecosystem responses of tropical forests to climate change

What is the long-term clinical outcome after fragility fractures of the pelvis? - A CT-based cross-sectional study

Background: Recently, Rommens and Hoffman introduced a CT-based classification system for fragility fractures of the pelvis (FFP). Although fracture characteristics have been described, the relationship with clinical outcome is lacking. The purpose of this study was to get insight into the type of treatment and subsequent clinical outcome after all types of FFP. Methods: A cross-sectional cohort study was performed including all elderly patients (≥ 65 years) with a CT-diagnosed FFP, between 2007-2019 in two level 1 trauma centers. Data regarding treatment, mortality and clinical outcome was gathered from the electronic patient files. Patients were asked to complete patient-reported outcome measures (PROMs) regarding physical functioning (SMFA) and quality of life (EQ-5D). Additionally, a standardized multidisciplinary treatment algorithm was constructed. Results: A total of 187 patients were diagnosed with an FFP of whom 117 patients were available for follow-up analysis and 58 patients responded. FFP type I was most common (60%), followed by type II (27%), type III (8%) and type IV (5%). Almost all injuries were treated non-operatively (98%). Mobility at six weeks ranged from 50% (type III) to 80% type II). Mortality at 1 year was respectively 16% (type I and II), 47% (type III) and 13% (type IV). Physical functioning (SMFA function index) ranged from 62 (type III and IV) to 69 (type II) and was significantly decreased (P=<0.001) compared to the age-matched general population. Quality of life was also significantly decreased, ranging from 0.26 (type III) to 0.69 (type IV). Conclusions: FFP type I and II are most common. Treatment is mainly non-operative, resulting in good mobility after six weeks, especially for patients with FFP type I and II. Mortality rates at one year were substantial in all patients. Physical functioning and quality of life was about 20-30% decreased compared to the general population

Enveloping Sophisticated Tools into Process-Centered Environments

We present a tool integration strategy based on enveloping pre-existing tools without source code modifications or recompilation, and without assuming an extension language, application programming interface, or any other special capabilities on the part of the tool. This Black Box enveloping (or wrapping) idea has existed for a long time, but was previously restricted to relatively simple tools. We describe the design and implementation of, and experimentation with, a new Black Box enveloping facility intended for sophisticated tools --- with particular concern for the emerging class of groupware applications

Spectroelectrochemical Sensing: Current Trends and Challenges

Spectroelectrochemistry (SEC) has been used for more than 50 years, but this set of techniques has not been widely used for quantitative analysis. For many years, no commercial instruments were available, which made very difficult to spread the use of SEC. Nowadays, only the creativity of the researchers is required to exploit the capabilities of SEC. This review is written with the aim of showing the potential of SEC, mainly for analytical chemistry. Here, we explain what SEC is, how analytical responses can be obtained, why these techniques are useful for sensors, with a brief description of its advantages in use, and, finally, we try to show the challenges that must be addressed in the next years. SEC can resolve interesting analytical problems using the high amount of data provided by this intrinsic trilinear technique. Given the quantitative analysis point of view of this review, the discussion of the SEC techniques is focused on UV/Vis absorption, photoluminescence and Raman SEC.Spectroelectrochemistry (SEC) has been used for more than 50 years, but this set of techniques has not been widely used for quantitative analysis. For many years, no commercial instruments were available, which made very difficult to spread the use of SEC. Nowadays, only the creativity of the researchers is required to exploit the capabilities of SEC. This review is written with the aim of showing the potential of SEC, mainly for analytical chemistry. Here, we explain what SEC is, how analytical responses can be obtained, why these techniques are useful for sensors, with a brief description of its advantages in use, and, finally, we try to show the challenges that must be addressed in the next years. SEC can resolve interesting analytical problems using the high amount of data provided by this intrinsic trilinear technique. Given the quantitative analysis point of view of this review, the discussion of the SEC techniques is focused on UV/Vis absorption, photoluminescence and Raman SEC.Ministerio de Economía y Competitividad (Grants CTQ2017-83935-R-AEI/FEDERUE) and Junta de Castilla y León (Grant BU033-U16 and BU297P18). J. G.–R. thanks UBU for his postdoctoral contract. J.V.P–R. thanks JCyL for his postdoctoral fellowship (Grant BU033-U16). Thanks to

TERMINAL REPORT ON THE MIGHTY MOUSE HIGHFLUX RESEARCH REACTOR PROJECT

The research and development program pertinent to the conceptual design and ultimate construction at ANL of an advanced research reactor with a peak thermal flux of 5 x 10/sup 15/ n/cm/sup 2//sec is documented. The basic reactor complex, the problems involved, the various approaches pursued, the present status and estimated cost of the project, along with recommendations for future research and development essential to the successful culmination of the project are described. The reactor is moderated with D,Oand has a core life of 120 hours at 250 Mw, (W.D.M.

TESTING OPTIMALITY WITH EXPERIMENTAL EVOLUTION: LYSIS TIME IN A BACTERIOPHAGE

Optimality models collapse the vagaries of genetics into simple trade-offs to calculate phenotypes expected to evolve by natural selection. Optimality approaches are commonly criticized for this neglect of genetic details, but resolution of this disagreement has been difficult. The importance of genetic details may be tested by experimental evolution of a trait for which an optimality model exists and in which genetic details can be studied. Here we evolved lysis time in bacteriophage T7, a virus of Escherichia coli. Lysis time is equivalent to the age of reproduction in an organism that reproduces once and then dies. Delaying lysis increases the number of offspring but slows generation time, and this trade-off renders the optimum sensitive to environmental conditions: earlier lysis is favored when bacterial hosts are dense, later lysis is favored when hosts are sparse. In experimental adaptations, T7 evolved close to the optimum in conditions favoring early lysis but not in conditions favoring late lysis. One of the late lysis adaptations exhibited no detectable phenotypic evolution despite genetic evolution; the other evolved only partly toward the expected optimum. Overall, the lysis time of the adapted phages remained closer to their starting values than predicted by the model. From the perspective of the optimality model, the experimental conditions were expected to select changes only along the postulated trade-off, but a trait outside the trade-off evolved as well. Evidence suggests that the model's failure ultimately stems from a violation of the trade-off, rather than a paucity of mutations