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DOE OSTI2014

Assessing and accounting for the impact of respiratory motion on FDG uptake and viable volume for liver lesions in free-breathing PET using respiration-suspended PET images as reference

Purpose: To assess and account for the impact of respiratory motion on the variability of activity and volume determination of liver tumor in positron emission tomography (PET) through a comparison between free-breathing (FB) and respiration-suspended (RS) PET images. Methods: As part of a PET/computed tomography (CT) guided percutaneous liver ablation procedure performed on a PET/CT scanner, a patient's breathing is suspended on a ventilator, allowing the acquisition of a near-motionless PET and CT reference images of the liver. In this study, baseline RS and FB PET/CT images of 20 patients undergoing thermal ablation were acquired. The RS PET provides near-motionless reference in a human study, and thereby allows a quantitative evaluation of the effect of respiratory motion on PET images obtained under FB conditions. Two methods were applied to calculate tumor activity and volume: (1) threshold-based segmentation (TBS), estimating the total lesion glycolysis (TLG) and the segmented volume and (2) histogram-based estimation (HBE), yielding the background-subtracted lesion (BSL) activity and associated volume. The TBS method employs 50% of the maximum standardized uptake value (SUV{sub max}) as the threshold for tumors with SUV{sub max} ≥ 2× SUV{sub liver-bkg}, and tumor activity above this threshold yields TLG{sub 50%}. The HBE method determines local PET background based on a Gaussian fit of the low SUV peak in a SUV-volume histogram, which is generated within a user-defined and optimized volume of interest containing both local background and lesion uptakes. Voxels with PET intensity above the fitted background were considered to have originated from the tumor and used to calculate the BSL activity and its associated lesion volume. Results: Respiratory motion caused SUV{sub max} to decrease from RS to FB by −15% ± 11% (p = 0.01). Using TBS method, there was also a decrease in SUV{sub mean} (−18% ± 9%, p = 0.01), but an increase in TLG{sub 50%} (18% ± 36%) and in the segmented volume (47% ± 52%, p = 0.01) from RS to FB PET images. The background uptake in normal liver was stable, 1% ± 9%. In contrast, using the HBE method, the differences in both BSL activity and BSL volume from RS to FB were −8% ± 10% (p = 0.005) and 0% ± 16% (p = 0.94), respectively. Conclusions: This is the first time that almost motion-free PET images of the human liver were acquired and compared to free-breathing PET. The BSL method's results are more consistent, for the calculation of both tumor activity and volume in RS and FB PET images, than those using conventional TBS. This suggests that the BSL method might be less sensitive to motion blurring and provides an improved estimation of tumor activity and volume in the presence of respiratory motion.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2024

Measurement of the 1-jettiness event shape observable in deep-inelastic electron-proton scattering at HERA

The H1 Collaboration reports the first measurement of the 1-jettiness event shape observable $τ^b_1$ in neutral-current deep-inelastic electron-proton scattering (DIS). The observable $τ^b_1$ is equivalent to a thrust observable defined in the Breit frame. The data sample was collected at the HERA ep collider in the years 2003–2007 with center-of-mass energy of $\sqrt{s}$ = 319 GeV, corresponding to an integrated luminosity of 351.1 pb -1 . Triple differential cross sections are provided as a function of $τ^b_1$, event virtuality $Q^2$, and inelasticity y, in the kinematic region $Q^2$ > 150 GeV 2 . Single differential cross section are provided as a function of $τ^b_1$ in a limited kinematic range. Double differential cross sections are measured, in contrast, integrated over $τ^b_1$ and represent the inclusive neutral-current DIS cross section measured as a function of $Q^2$ and y. The data are compared to a variety of predictions and include classical and modern Monte Carlo event generators, predictions in fixed-order perturbative QCD where calculations up to $\mathcal{O}$($α^3_s$) are available for $τ^b_1$ or inclusive DIS, and resummed predictions at next-to-leading logarithmic accuracy matched to fixed order predictions at $\mathcal{O}$($α^2_s$). These comparisons reveal sensitivity of the 1-jettiness observable to QCD parton shower and resummation effects, as well as the modeling of hadronization and fragmentation. Within their range of validity, the fixed-order predictions provide a good description of the data. Monte Carlo event generators are predictive over the full measured range and hence their underlying models and parameters can be constrained by comparing to the presented data.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

NASA NTRS1969

Surveyor Project Final Report: Part 1 - Project Description and Performance, Volume 1

The Surveyor Project planned and conducted seven unmanned lunar missions for which spacecraft were launched between May 1966 and January 1968. Each of the spacecraft was successfully launched with the then newly developed Atlas/Centaur vehicle which utilized for the first time a high-specific-impulse, liquid hydrogen/liquid oxygen fueled stage. Five of the spacecraft successfully soft-landed and returned a great quantity of engineering and scientific data on extensive postlanding operations, accomplishing all mission and project objectives. Four of the spacecraft soft-landed at selected mare sites to provide data which were required to support the Apollo Program. The final spacecraft was then successfully used for scientific investigation of a contrasting site in the rugged lunar highlands. Surveyor was a fully attitude-stabilized spacecraft designed to receive and execute a wide variety of earth commands, as well as to perform certain automatic functions including the critical terminal-descent and soft-landing sequences. Significant new and advanced subsystems that were developed and/or used in combination to enable Surveyor to execute the complex terminal phase of flight were: (1) a solid-propellant main retro motor, (2) throttlable liquid-propellant vernier engines (also used for midcourse velocity correction), (3) highly sensitive velocity- and altitude-sensing radars, and (4) an automatic closed-loop guidance and control system. The first Surveyor spacecraft carried a survey television camera which, together with other engineering instrumentation, obtained in-flight and postlanding data. The complement of instruments carried on later missions included various combinations of the following additional devices: (1) a soil mechanics/surface sampler instrument for picking, digging, and handling lunar surface material; (2) an alpha scattering instrument for performing a chemical analysis of the lunar surface material; and (3) magnets attached to the spacecraft for determining magnetic properties of the soil.

Jet Propulsion Laboratory↗

NASA NTRS1969

Surveyor Project Final Report: Part 1 - Project Description and Performance, Volume 2

Jet Propulsion Laboratory↗

NASA NTRS1983

Recovery of damage in rad-hard MOS devices during and after irradiation by electrons, protons, alphas, and gamma rays

This paper reports on the recovery properties of rad-hard MOS devices during and after irradiation by electrons, protons, alphas, and gamma rays. The results indicated that complex recovery properties controlled the damage sensitivities of the tested parts. The results also indicated that damage sensitivities depended on dose rate, total dose, supply bias, gate bias, transistor type, radiation source, and particle energy. The complex nature of these dependencies make interpretation of LSI device performance in space (exposure to entire electron and proton spectra) difficult, if not impossible, without respective ground tests and analyses. Complete recovery of n-channel shifts was observed, in some cases within hours after irradiation, with equilibrium values of threshold voltages greater than their pre-irradiation values. This effect depended on total dose, radiation source, and gate bias during exposure. In contrast, the p-channel shifts recovered only 20 percent within 30 days after irradiation.

Brucker, G. J.↗

NASA NTRS2001

Using the Human Eye to Characterize Displays

Monitor characterization has taken on new importance for non-professional users, who are not usually equipped to make photometric measurements. We studied adjusting brightness to set the black level, banding effects due to digitization, and gamma estimation in the light and in the dark, and a color-matching task in the light, on a desktop CRT (Cathode-Ray Tube) and a laptop LCD (Liquid Crystal Display). Observers demonstrated the sensitivity of the visual system for comparative judgments in black-level adjustment, banding visibility, and gamma estimation. The results of the color-matching task were ambiguous. In the brightness adjustment task, the action of the adjustment was not as presumed; however, perceptual judgments were as expected under the actual conditions. When the gamma estimates of observers were compared to photometric measurements, problems with the definition of gamma were identified. Information about absolute light levels that would be important for characterizing a displays, given the shortcomings of gamma in measuring apparent contrast, are not measurable by eye alone. The LCD was not studied as extensively as the CRT because of viewing-angle problems, and its transfer function did not follow a power law, rendering gamma estimation meaningless.

Gille, Jennifer↗

NASA NTRS2001

Using the Human Eye to Characterize Displays

Monitor characterization has taken on new importance for non-professional users, who are not usually equipped to make photometric measurements. Our purpose was to examine some of the visual judgments used in characterization schemes that have been proposed for web users. We studied adjusting brightness to set the black level, banding effects due to digitization, and gamma estimation in the light and in the dark, and a color-matching task in the light, on a desktop CRT and a laptop LCD. Observers demonstrated the sensitivity of the visual system for comparative judgments in black-level adjustment, banding visibility, and gamma estimation. The results of the color-matching task were ambiguous. In the brightness adjustment task, the action of the adjustment was not as presumed; however, perceptual judgments were as expected under the actual conditions. When the gamma estimates of observers were compared to photometric measurements, problems with the definition of gamma were identified. Information about absolute light levels that would be important for characterizing a display, given the shortcomings of gamma in measuring apparent contrast, are not measurable by eye alone. The LCD was not studied as extensively as the CRT because of viewing-angle problems, and its transfer function did not follow a power law, rendering gamma estimation meaningless.

Gille, Jennifer↗

DOE OSTI2020

Quantifying redox heterogeneity in single-crystalline LiCoO 2 cathode particles

Active cathode particles are fundamental architectural units for the composite electrode of Li-ion batteries. The microstructure of the particles has a profound impact on their behavior and, consequently, on the cell-level electrochemical performance. LiCoO 2 (LCO, a dominant cathode material) is often in the form of well-shaped particles, a few micrometres in size, with good crystallinity. In contrast to secondary particles (an agglomeration of many fine primary grains), which are the other common form of battery particles populated with structural and chemical defects, it is often anticipated that good particle crystallinity leads to superior mechanical robustness and suppressed charge heterogeneity. Yet, sub-particle level charge inhomogeneity in LCO particles has been widely reported in the literature, posing a frontier challenge in this field. Herein, this topic is revisited and it is demonstrated that X-ray absorption spectra on single-crystalline particles with highly anisotropic lattice structures are sensitive to the polarization configuration of the incident X-rays, causing some degree of ambiguity in analyzing the local spectroscopic fingerprint. To tackle this issue, a methodology is developed that extracts the white-line peak energy in the X-ray absorption near-edge structure spectra as a key data attribute for representing the local state of charge in the LCO crystal. This method demonstrates significantly improved accuracy and reveals the mesoscale chemical complexity in LCO particles with better fidelity. In addition to the implications on the importance of particle engineering for LCO cathodes, the method developed herein also has significant impact on spectro-microscopic studies of single-crystalline materials at synchrotron facilities, which is broadly applicable to a wide range of scientific disciplines well beyond battery research.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗

DOE OSTI2021

Solid Electrolyte Interphase Architecture Determined through In Situ Neutron Scattering

We demonstrate through a combination of in operando solvent exchange and depth-sensitive neutron reflectometry that the solid electrolyte interphase (SEI) formed after the initial lithiation of a silicon anode, using a standard LiPF6 ethylene carbonate/ethyl methyl carbonate electrolyte, is chemically homogeneous across the liquid-solid interface. The data show the SEI is accessible to solvent/salt exchange throughout the layer indicating the poorly bound nature of the SEI components. Further, the data indicates that P-F species, from the decomposition of the LiPF6 salt, are highly mobile and removed from the SEI with solvent exchange. Critically, the SEI layer is structurally homogenous, in contrast to the reports in the literature of an inorganic/organic bilayer, which is important to our understanding of SEI formation and chemistry.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

NASA NTRS1986

Airborne and spaceborne radar images for geologic and environmental mapping in the Amazon rain forest, Brazil

Spaceborne and airborne radar image of portions of the Middle and Upper Amazon basin in the state of Amazonas and the Territory of Roraima are compared for purposes of geological and environmental mapping. The contrasted illumination geometries and imaging parameters are related to terrain slope and surface roughness characteristics for corresponding areas that were covered by each of the radar imaging systems. Landforms range from deeply dissected mountain and plateau with relief up to 500 m in Roraima, revealing ancient layered rocks through folded residual mountains to deeply beveled pediplain in Amazonas. Geomorphic features provide distinct textural signatures that are characteristic of different rock associations. The principle drainages in the areas covered are the Rio Negro, Rio Branco, and the Rio Japura. Shadowing effects and low radar sensitivity to subtle linear fractures that are aligned parallel or nearly parallel to the direction of radar illumination illustrate the need to obtain multiple coverage with viewing directions about 90 degrees. Perception of standing water and alluvial forest in floodplains varies with incident angle and with season. Multitemporal data sets acquired over periods of years provide an ideal method of monitoring environmental changes.

Ford, John P.↗

DOE OSTI2016

Correlates of Sensitive Technologies

By “Quantitative Empirical Analysis” (QEA) is intended the use of statistical methods to infer, from data that often tend to be of a historical nature, the characteristics of states that correlate with some designated dependent variable (e.g. proliferation of nuclear weapons). QEA is a well-established approach in the social sciences, but is not notably well-known among physical scientists, who tend to think of the social sciences as inherently qualitative. This article attempts to provide a snapshot of research, most of which has evolved over the past decade, involving the application of QEA to issues in which the dependent variable of interest is intended as some measure of nuclear proliferation. Standard practices in QEA are described, especially as they relate to data collection. The QEA approach is compared and contrasted to other quantitative approaches to studying proliferation-related issues, including a “figure of merit” approach that has largely been developed within the DOE complex, and two distinct methodologies termed in a recent US National Academy of Sciences study as “case by case” and “predefined framework.” Sample results from QEA applied to proliferation are indicated, as are doubts about such quantitative approaches. A simplistic decision-theoretic model of the optimal time for the international community to intervene in a possible proliferation scenario is used to illustrate the possibility of synergies between different approaches

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗

DOE OSTI2018

Clinical Indication for Computed Tomography During Hepatic Arteriography (CTHA) in Addition to Dynamic CT Studies to Identify Hypervascularity of Hepatocellular Carcinoma

PurposeTo identify factors benefiting from computed tomography during hepatic arteriography (CTHA) in addition to dynamic CT studies at the preoperative evaluation of the hypervascularity of hepatocellular carcinoma (HCC).Materials and MethodsWe retrospectively divided 45 patients with HCC, who underwent both dynamic CT (dCT) and CTHA, into two groups based on the number of hypervascular HCCs identified on dCT and CTHA studies. In group A, the number of HCCs identified by dCT and CTHA was the same and additive CTHA had not been indicated. In group B, fewer HCCs were counted on dCT than on CTHA images, indicating that additive CTHA studies had been appropriate. We compared the patient characteristics, the serum alpha-fetoprotein level, and the tumor-liver contrast (TLC) of the main tumor on dCT scans of both groups. To identify factors alerting to the benefit of additional CTHA studies, we performed univariate logistic regression analysis. Statistically significant parameters were subjected to receiver operating characteristic analysis for obtaining the optimal cutoff value indicative of the benefit of CTHA.ResultsUnivariate analysis identified only the TLC of the main tumor on dCT images as a significant factor for the benefit of CTHA images (P < 0.01). At the optimal cutoff value for the TLC of the main tumor on dCT images (15.9 Hounsfield units), the sensitivity and specificity for the benefit of CTHA were 85.0 and 92.0%, respectively.ConclusionEvaluation of the TLC of the main tumor on dCT scans identifies patients in whom additive CTHA studies are beneficial.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2018

Probing Light Atoms at Subnanometer Resolution: Realization of Scanning Transmission Electron Microscope Holography

Atomic resolution imaging of light elements in electron-transparent materials has long been a challenge. Biomolecular materials, for example, are rapidly altered by incident electrons. We demonstrate a scanning transmission electron microscopy (STEM) technique, called STEM holography, capable of efficient structural analysis of beam-sensitive nanomaterials. STEM holography measures the absolute phase and amplitude of electrons passed through a specimen via interference with a vacuum reference wave. We use an amplitude-dividing nanofabricated grating to prepare multiple beams focused at the sample. We configure the postspecimen microscope imaging system to overlap the beams, forming an interference pattern. We record and analyze the pattern at each 2D-raster-scan-position, reconstructing the complex object wave. As a demonstration, we image gold nanoparticles on an amorphous carbon substrate at 2.4 Å resolution. In conclusion STEM holography offers higher contrast of the carbon while maintaining gold atomic lattice resolution compared to high angle annular dark field STEM.

4D-STEM↗

DOE OSTI2026

Gepta-EX: a multi-channel germanium detector for X-ray absorption fine structure

Fluorescence-mode X-ray absorption spectroscopy (XAS) at high photon energies requires detectors with high stopping power and excellent energy resolution to measure weak element-specific signals. Traditional silicon-based detectors suffer from poor efficiency above ∼20 keV, while most high-Z materials such as cadmium telluride, cadmium zinc telluride, and gallium arsenide have focused predominantly on imaging applications with limited spectroscopic resolution. In contrast, germanium combines excellent stopping power with superior intrinsic energy resolution due to its low Fano factor and favorable charge transport properties, making it ideal for high-resolution spectroscopy in the 15 keV to 100 keV range. To address these requirements, we report on the development, fabrication, and performance evaluation of Gepta-EX, a compact multi-channel high-purity germanium (HPGe) detector system for fluorescence-mode XAS. The Gepta-EX system features a monolithic seven-channel HPGe pixel array integrated with low-noise CUBE charge-sensitive preamplifiers, housed within a thermally isolated compact cryostat operating near 90 K. The detector achieves energy resolutions of 218 eV at 5.9 keV (from a 55 Fe source) and 373 eV at 59.5 keV (from a 241 Am source), with uniform performance across all channels. By avoiding the escape peak interference commonly associated with silicon detectors and providing stable, high-resolution performance, Gepta-EX represents a powerful tool for high-energy X-ray spectroscopy.

36 MATERIALS SCIENCE↗

DOE OSTI2014

SU-D-18C-05: Variable Bolus Arterial Spin Labeling MRI for Accurate Cerebral Blood Flow and Arterial Transit Time Mapping

Purpose: Arterial spin labeling (ASL) is an MRI perfusion imaging method from which quantitative cerebral blood flow (CBF) maps can be calculated. Acquisition with variable post-labeling delays (PLD) and variable TRs allows for arterial transit time (ATT) mapping and leads to more accurate CBF quantification with a scan time saving of 48%. In addition, T1 and M0 maps can be obtained without a separate scan. In order to accurately estimate ATT and T1 of brain tissue from the ASL data, variable labeling durations were invented, entitled variable-bolus ASL. Methods: All images were collected on a healthy subject with a 3T Siemens Skyra scanner. Variable-bolus Psuedo-continuous ASL (PCASL) images were collected with 7 TI times ranging 100-4300ms in increments of 700ms with TR ranging 1000-5200ms. All boluses were 1600ms when the TI allowed, otherwise the bolus duration was 100ms shorter than the TI. All TI times were interleaved to reduce sensitivity to motion. Voxel-wise T1 and M0 maps were estimated using a linear least squares fitting routine from the average singal from each TI time. Then pairwise subtraction of each label/control pair and averaging for each TI time was performed. CBF and ATT maps were created using the standard model by Buxton et al. with a nonlinear fitting routine using the T1 tissue map. Results: CBF maps insensitive to ATT were produced along with ATT maps. Both maps show patterns and averages consistent with literature. The T1 map also shows typical T1 contrast. Conclusion: It has been demonstrated that variablebolus ASL produces CBF maps free from the errors due to ATT and tissue T1 variations and provides M0, T1, and ATT maps which have potential utility. This is accomplished with a single scan in a feasible scan time (under 6 minutes) with low sensivity to motion.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2019

Hydrogen Generation Rates for Saltstone Related Samples with Tank 50 Waste Grout and Glycoate Using Sealed Reactors

This report documents the results of sealed reactor tests to measure the hydrogen generation rate (HGR) from Tank 50 waste, which may be on the order of 3 x 10 -9 (ft 3 /h)/gal. Because the estimated HGR limit of detection (LOD) for an open, continuous flow system is approximately 6 x 10 -8 (ft 3 /h)/gal a more sensitive method was needed. By accumulating generated gases in a sealed system without a continuous purge gas, the resulting concentrations can increase the sensitivity of measurement, which is based on duration of heating. Prior sealed-reactor testing demonstrated measurements down to 7 x 10 -10 (ft 3 /h)/gal. In 2017, Savannah River Remediation, LLC (SRR) declared a Potential Inadequacy in the Safety Analysis (PISA) for the Saltstone Production Facility (SPF), among other facilities. The research for this report concerns waste from Tank 50 which is processed through SPF to produce saltstone. Previous studies examined the thermolysis of Tank 50 waste mixed with small individual amounts of saltstone grout premix additives, as well as glycolate. In contrast, the current study evaluated the impact of Tank 50 waste containing glycolate and stabilized within saltstone, on the generation of flammable gases, specifically hydrogen. The task included holding at target temperatures Tank 50 samples of salt solution in grout and spiked with 350 mg/L of glycolate to determine if the glycolate decomposes into H 2 . The measured hydrogen generation rates for radioactive saltstone monoliths over 28 days are: 2.0 x 10 -7 (ft 3 /h)/gal at 64-68°C, 1.4 x 10 -7 (ft 3 /h)/gal at 80-82°C, and 4.5 x 10 -7 (ft 3 /h)/gal at 112°C. Testing also included a non-radioactive salt simulant of Tank 50 waste, which was spiked with a concentration of glycolate expected in Savannah River Site (SRS) low-level waste, after the waste is solidified in grout. Included in the simulant tests was using grout made with two different surface areas, a monolith form with only the upper surface exposed and a pellet, or cube, form to increase the exposed surface area, to demonstrate the importance of exposed area in H 2 generation.

08 HYDROGEN↗

DOE OSTI2026

Transitions, Dynamics, and Driven States in Quantum Magnets (Final Report Revised)

Transitions into unusual electronic, optical, and magnetic states at the absolute zero of temperature display special properties that teach us about fundamental quantum mechanics and also underlie important technologies. These so-called quantum phase transitions intertwine the static and dynamical responses of the materials changing state. They are extremely sensitive to the effects of disorder and etch in high relief the role of quantum fluctuations. There are ample questions remaining about the character of such transitions and the nature of the competing quantum states. There are also opportunities to drive quantum materials out of equilibrium, with the possibility of new types of correlated and coherent order, and new ways to access the dynamical evolution of ground and excited states. We have investigated how the order develops in time and space, and the nature of the final configurations. We are able to compare and contrast classical and quantum excitations in our experimental system of choice, and thereby can trace the relative speed by which the system settles into its lowest-energy ground state. This comparison of quantum and classical annealing protocols lies at the heart of strategies for harnessing the power of quantum computers dedicated to optimization problems. A combination of magnetic susceptibility measurements at finite frequency where the magnetic spins are queried by an external ac field, dc magnetometry measurements that characterize the macroscopic strength of magnetic order and its resistance to change, noise measurements that reveal the microscopic fluctuations of the spins as they prepare to change state, and microwave spectroscopy to look at the response of both the electronic and nuclear degrees of freedom, have been performed as functions of temperature, magnetic field, frequency, excitation amplitude, magnetic spin concentration, and disorder. This combination of probes addresses issues of stability over time, overlap between spin states, the ability of the spins to respond independently or coherently, and the promise of control on the nanometer length scale. The research reported here provides insights into fundamental quantum physics. It also addresses the question of how best to use complex systems, such as magnetic solids, to stably process quantum information.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

NASA NTRS2009

The Long, Hard Journey: Expanding the Use of NASA Data and Models for Sustainable Development Planning Around the World

In 2007, the National Research Council's committee on Extending Observations and Research Results to Practical Applications recommended that NASA's Applied Science Program (ASP) directly engage with a broader community of users - not just federal agencies. Soon afterwards, scientists at the NASA Marshall Space Flight Center began discussions on a collaborative research project with EMBARQ - the World Resource Institute's Center for Sustainable Transport. The discussions initially focused on how best to utilize satellite observations and atmospheric models for assessing the impact of a proposed transportation project on land use and air quality. Discussions exposed the participants to a broad spectrum of science and policy challenges that these diverse organizations face on a routine basis. It brought into clear focus the need for an observation-modeling system that will allow a proactive approach towards development planning, and the fact that satellite systems do not always provide the spatial and temporal resolution useful for urban-scale applications, underscoring the need for earth system models to bridge this gap. Realizing the significant risk that unplanned urbanization and climate change pose to the social and functional stability of large cities, both organizations decided to expand the scope of their preliminary discussion to include water resources and agriculture. A pilot project, funded by NASA ASP, EMBARQ and Istanbul Technical University focused on quantifying the magnitude and extent of urbanization in Istanbul, and analyzed the combined effect of urbanization and projected climate change on local climate, air quality, and its consequent effects on agricultural productivity. Preliminary results show that Istanbul has undergone a significant amount of Land Use/Land Cover change over the past two decades. While some forested areas have been lost to urban-landscapes, urbanization has mostly occurred over former croplands due to the fact that in contrast to forested areas, croplands have flat terrain, making them a more attractive target for conversion to urban land. The reduction in land area for agricultural and increase in temperature has reduced agricultural production in the vicinity of the city. The United Nations expects the world population to reach 9.2 billion by 2050. Most of this increase will be absorbed by countries that are least able to sustain it. Rapid economic growth is likely to continue and will require massive infrastructure investments. If not properly managed, the magnitude and extent of these initiatives will overwhelm sensitive ecosystems around the world. Successful relationships such as the one described here are critically important if we are to stabilize the threatened ecosystems on which human systems ultimately rely. The challenges, needs, culture, and operating environment of development planning organizations are fundamentally different from a research organization. An appreciation of these differences is a prerequisite for any successful collaboration.

Khan, Maudood↗