SEARCH · Engineering Papers

Results for “FATS”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 523 records · Page 29

All sources NASA NTRS DOE OSTI

DOE OSTI2011

Selective Photothermolysis to target Sebaceous Glands: Theoretical Estimation of Parameters and Preliminary Results Using a Free Electron Laser

The success of permanent laser hair removal suggests that selective photothermolysis (SP) of sebaceous glands, another part of hair follicles, may also have merit. About 30% of sebum consists of fats with copious CH2 bond content. SP was studied in vitro, using free electron laser (FEL) pulses at an infrared CH2 vibrational absorption wavelength band. Absorption spectra of natural and artificially prepared sebum were measured from 200 nm to 3000 nm, to determine wavelengths potentially able to target sebaceous glands. The Jefferson National Accelerator superconducting FEL was used to measure photothermal excitation of aqueous gels, artificial sebum, pig skin, human scalp and forehead skin (sebaceous sites). In vitro skin samples were exposed to FEL pulses from 1620 to 1720 nm, spot diameter 7-9.5 mm with exposure through a cold 4C sapphire window in contact with the skin. Exposed and control tissue samples were stained using H and E, and nitroblue tetrazolium chloride staining (NBTC) was used to detect thermal denaturation. Natural and artificial sebum both had absorption peaks near 1210, 1728, 1760, 2306 and 2346 nm. Laser-induced heating of artificial sebum was approximately twice that of water at 1710 and 1720 nm, and about 1.5x higher in human sebaceous glands than in water. Thermal camera imaging showed transient focal heating near sebaceous hair follicles. Histologically, skin samples exposed to {approx}1700 nm, {approx}100-125 ms pulses showed evidence of selective thermal damage to sebaceous glands. Sebaceous glands were positive for NBTC staining, without evidence of selective loss in samples exposed to the laser. Epidermis was undamaged in all samples. Conclusions: SP of sebaceous glands appears to be feasible. Potentially, optical pulses at {approx}1720 nm or {approx}1210 nm delivered with large beam diameter and appropriate skin cooling in approximately 0.1 s may provide an alternative treatment for acne.

59 BASIC BIOLOGICAL SCIENCES↗

DOE OSTI2019

Improved reconstruction stability for chemical shift encoded hyperpolarized 13 C magnetic resonance spectroscopic imaging using k‐t spiral acquisitions

Purpose A multiecho, field of view (FOV)‐oversampled k‐t spiral acquisition and direct iterative decomposition of water and fat with echo asymmetry and least‐squares estimation reconstruction is demonstrated to improve the stability of hyperpolarized 13 C magnetic resonance spectroscopic imaging (MRSI) in the presence of signal ambiguities attributed to low‐SNR (signal‐to‐noise‐ratio) species, local uncertainties in metabolite peaks, and echo‐to‐echo signal inconsistencies. Theory k‐t spiral acquisitions redistribute readout points to be more densely spaced radially in k‐space by acquiring an FOV and matrix that are oversampled by η . These more densely spaced spiral turns constitute effective intraspiral echoes and can supplement conventional interspiral echoes to improve spectral separation and reduce spectral cross‐talk to better resolve 13 C‐labeled species for spectroscopic imaging. Methods Digital simulations and imaging phantom experiments were performed for a range of interspiral echo spacings and η using multiecho, k‐t spiral acquisitions. Image spectral cross‐talk artifacts were evaluated both qualitatively and quantitatively as the percent error in measured metabolite ratios. In vivo murine experiments evaluated the feasibility of multiecho, k‐t spiral [1‐ 13 C]pyruvate MRSI to reduce spectral cross‐talk for 3 scenarios of different expected reconstruction stability. Results Digital simulations and imaging phantom experiments both demonstrated reduced or comparable image spectral cross‐talk and percent errors in measured metabolite ratios with increasing η and better choices of echo spacings. In vivo images displayed markedly reduced spectral cross‐talk in lactate images acquired with η = 7 versus η = 1. Conclusion The precision of hyperpolarized 13 C metabolic imaging and quantification in the presence of low‐SNR species, local uncertainties in metabolite resonances, and echo‐to‐echo signal inconsistencies can be improved with the use of FOV‐oversampled k‐t spiral acquisitions.

Macdonald, Erin B.↗

DOE OSTI2017

Cloud feedback mechanisms and their representation in global climate models

Cloud feedback—the change in top-of-atmosphere radiative flux resulting from the cloud response to warming—constitutes by far the largest source of uncertainty in the climate response to CO 2 forcing simulated by global climate models (GCMs). In this paper, we review the main mechanisms for cloud feedbacks, and discuss their representation in climate models and the sources of intermodel spread. Global-mean cloud feedback in GCMs results from three main effects: (1) rising free-tropospheric clouds (a positive longwave effect); (2) decreasing tropical low cloud amount (a positive shortwave [SW] effect); (3) increasing high-latitude low cloud optical depth (a negative SW effect). These cloud responses simulated by GCMs are qualitatively supported by theory, high-resolution modeling, and observations. Rising high clouds are consistent with the fixed anvil temperature (FAT) hypothesis, whereby enhanced upper-tropospheric radiative cooling causes anvil cloud tops to remain at a nearly fixed temperature as the atmosphere warms. Tropical low cloud amount decreases are driven by a delicate balance between the effects of vertical turbulent fluxes, radiative cooling, large-scale subsidence, and lower-tropospheric stability on the boundary-layer moisture budget. High-latitude low cloud optical depth increases are dominated by phase changes in mixed-phase clouds. Finally, the causes of intermodel spread in cloud feedback are discussed, focusing particularly on the role of unresolved parameterized processes such as cloud microphysics, turbulence, and convection.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2018

Hexapod coloron at the LHC

Instead of the usual dijet decay, the coloron may mainly decay into its own “Higgs bosons”, which subsequently decay into many jets. This is a general feature of the renormalizable coloron model, where the corresponding “Higgs bosons” are a color-octet Θ and a color-singlet φ I . In this paper, we perform a detailed collider study for the signature of p p → G ′ → ( Θ   → g g ) ( ϕ I → g g q q ¯ ) with the coloron G' as a six-jet resonance. For a light φ I below around 0.5 TeV, it may be boosted and behave as a four-prong fat jet. We also develop a jet-substructure-based search strategy to cover this boosted φ I case. Independent of whether φ I is boosted or not, the 13 TeV LHC with 100 fb -1 has great discovery potential for a coloron with the mass sensitivity up to 5 TeV.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2015

Resolving boosted jets with XCone

We show how the recently proposed XCone jet algorithm smoothly interpolates between resolved and boosted kinematics. When using standard jet algorithms to reconstruct the decays of hadronic resonances like top quarks and Higgs bosons, one typically needs separate analysis strategies to handle the resolved regime of well-separated jets and the boosted regime of fat jets with substructure. XCone, by contrast, is an exclusive cone jet algorithm that always returns a fixed number of jets, so jet regions remain resolved even when (sub)jets are overlapping in the boosted regime. In this paper, we perform three LHC case studies $-$ dijet resonances, Higgs decays to bottom quarks, and all-hadronic top pairs$-$ that demonstrate the physics applications of XCone over a wide kinematic range.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

DOE OSTI2013

Increased Production of Fatty Acids and Triglycerides in Aspergillus oryzae by Enhancing Expressions of Fatty Acid Synthesis-Related Genes

Microbial production of fats and oils is being developedas a means of converting biomass to biofuels. Here we investigate enhancing expression of enzymes involved in the production of fatty acids and triglycerides as a means to increase production of these compounds in Aspergillusoryzae. Examination of the A.oryzaegenome demonstrates that it contains twofatty acid synthases and several other genes that are predicted to be part of this biosynthetic pathway. We enhancedthe expressionof fatty acid synthesis-related genes by replacing their promoters with thepromoter fromthe constitutively highly expressedgene tef1. We demonstrate that by simply increasing the expression of the fatty acid synthasegenes we successfullyincreasedtheproduction of fatty acids and triglyceridesby more than two fold. Enhancement of expression of the fatty acid pathway genes ATP-citrate lyase and palmitoyl-ACP thioesteraseincreasedproductivity to a lesser extent.Increasing expression ofacetyl-CoA carboxylase caused no detectable change in fatty acid levels. Increases in message level for each gene were monitored usingquantitative real-time RT-PCR. Our data demonstrates that a simple increase in the abundance of fatty acid synthase genes can increase the detectable amount of fatty acids.

Fatty acid,Triglyceride, Biofuel, Fungi, Aspergill↗

DOE OSTI2019

Deep learning and radiomics: the utility of Google TensorFlow™ Inception in classifying clear cell renal cell carcinoma and oncocytoma on multiphasic CT

Purpose: Currently, all solid enhancing renal masses without microscopic fat are considered malignant until proven otherwise and there is substantial overlap in the imaging findings of benign and malignant renal masses, particularly between clear cell RCC (ccRCC) and benign oncocytoma (ONC). Radiomics has attracted increased attention for its utility in pre-operative work-up on routine clinical images. Radiomics based approaches have converted medical images into mineable data and identified prognostic imaging signatures that machine learning algorithms can use to construct predictive models by learning the decision boundaries of the underlying data distribution. The TensorFlow™ framework from Google is a state-of-the-art open-source software library that can be used for training deep learning neural networks for performing machine learning tasks. The purpose of this study was to investigate the diagnostic value and feasibility of a deep learning-based renal lesion classifier using open-source Google TensorFlow™ Inception in differentiating ccRCC from ONC on routine four-phase MDCT in patients with pathologically confirmed renal masses. Methods: With institutional review board approval for this 1996 Health Insurance Portability and Accountability Act compliant retrospective study and a waiver of informed consent, we queried our institution’s pathology, clinical, and radiology databases for histologically proven cases of ccRCC and ONC obtained between January 2000 and January 2016 scanned with a an intravenous contrast-enhanced four-phase renal mass protocol (unenhanced (UN), corticomedullary (CM), nephrographic (NP), and excretory (EX) phases). To extract features to be used for the machine learning model, the entire renal mass was contoured in the axial plane in each of the four phases, resulting in a 3D volume of interest (VOI) representative of the entire renal mass. We investigated thirteen different approaches to convert the acquired VOI data into a set of images that adequately represented each tumor which was used to train the final layer of the neural network model. Training was performed over 4000 iterations. In each iteration, 90% of the data were designated as training data and the remaining 10% served as validation data and a leave-one-out cross-validation scheme was implemented. Accuracy, sensitivity, specificity, positive (PPV) and negative predictive (NPV) values, and CIs were calculated for the classification of the thirteen processing modes. Results: We analyzed 179 consecutive patients with 179 lesions (128 ccRCC and 51 ONC). The ccRCC cohort had a mean size of 3.8 cm (range 0.8–14.6 cm) and the ONC cohort had a mean lesion size of 3.9 cm (range 1.0–13.1 cm). The highest specificity and PPV (52.9% and 80.3%, respectively) were achieved in the EX phase when we analyzed the single mid-slice of the tumor in the axial, coronal and sagittal plane, and when we increased the number of mid-slices of the tumor to three, with an accuracy of 75.4%, which also increased the sensitivity to 88.3% and the PPV to 79.6%. Using the entire tumor volume also showed that classification performance was best in the EX phase with an accuracy of 74.4%, a sensitivity of 85.8% and a PPV of 80.1%. When the entire tumor volume, plus mid-slices from all phases and all planes presented as tiled images, were submitted to the final layer of the neural network we achieved a PPV of 82.5%. Conclusions: The best classification result was obtained in the EX phase among the thirteen classification methods tested. Our proof of concept study is the first step towards understanding the utility of machine learning in the differentiation of ccRCC from ONC on routine CT images. We hope this could lead to future investigation into the development of a multivariate machine learning model which may augment our ability to accurately predict renal lesion histology on imaging.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2019

Diffusion tensor imaging of the kidney in healthy controls and in children and young adults with autosomal recessive polycystic kidney disease

Objective: To compare diffusion tensor imaging (DTI) of the kidneys and its derived parameters in children with autosomal recessive polycystic kidney disease (ARPKD) versus healthy controls. Methods: In a prospective IRB-approved study, we evaluated the use of DTI to compare kidney parenchyma FA values in healthy controls (age-matched children with no history of renal disease) versus patients with ARPKD. A 20-direction DTI with b-values of b = 0 s/mm{sup 2} and b = 400 s/mm{sup 2} was used to acquire data in coronal direction using a fat-suppressed spin-echo echo-planar sequence. Diffusion Toolkit and TrackVis were used for analysis and segmentation. TrackVis was used to draw regions of interest (ROIs) covering the entire volume of the renal parenchyma, excluding the collecting system. Fibers were reconstructed using a deterministic fiber tracking algorithm. The FA values based on the ROI data, mean length, and volume of the tracks based on the fiber tracking data were recorded. Results: Eight healthy controls (mean age = 12.9 years ± 4.0; 1/8 males) and six ARPKD participants (mean age = 13.8 years ± 8.5; 5/6 males) were included in the study. Compared to healthy controls, patients with ARPKD had significantly lower FA values (0.33 ± 0.03 vs. 0.25 ± 0.02, p = 0.002) and mean track length (16.73 ± 3.43 vs. 11.61 ± 1.29 mm, p = 0.005). Conclusion: DTI of the kidneys shows significantly lower FA values and mean track length in children and young adults with ARPKD compared to normal subjects. DTI of the kidney offers a novel approach for characterizing renal disease based on changes in diffusion anisotropy and kidney structure.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2019

Magnetic resonance imaging as a non-invasive method for the assessment of pancreatic fibrosis (MINIMAP): a comprehensive study design from the consortium for the study of chronic pancreatitis, diabetes, and pancreatic cancer

Characteristic features of chronic pancreatitis (CP) may be absent on standard imaging studies. Quantitative Magnetic Resonance Imaging (MRI) techniques such as T{sub 1} mapping, extracellular volume (ECV) fraction, diffusion-weighted imaging (DWI) with apparent diffusion coefficient map (ADC), MR elastography (MRE), and T{sub 1}-weighted signal intensity ratio (SIR) have shown promise for the diagnosis and grading severity of CP. However, radiologists still use the Cambridge classification which is based on traditional ductal imaging alone. There is an urgent need to develop new diagnostic criteria that incorporate both parenchymal and ductal features of CP seen by MRI/MRCP. Designed to fulfill this clinical need, we present the MINIMAP study, which was funded in September 2018 by the National Institutes of Health. This is a comprehensive quantitative MR imaging study which will be performed at multiple institutions in well-phenotyped CP patient cohorts. We hypothesize that quantitative MRI/MRCP features can serve as valuable non-invasive imaging biomarkers to detect and grade CP. We will evaluate the role of T{sub 1} relaxometry, ECV, T{sub 1}-weighted gradient echo SIR, MRE, arteriovenous enhancement ratio, ADC, pancreas volume/atrophy, pancreatic fat fraction, ductal features, and pancreatic exocrine output following secretin stimulation in the assessment of CP. We will attempt to generate a multi-parametric pancreatic tissue fibrosis (PTF) scoring system. We anticipate that a quantitative scoring system may serve as a biomarker of pancreatic fibrosis; hence this imaging technique can be used in clinical practice as well as clinical trials to evaluate the efficacy of agents which may slow the progression or reverse measures of CP.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2011

Symptomatic Spinal Epidural Lipomatosis After a Single Local Epidural Steroid Injection

Spinal epidural lipomatosis is a rare disorder that can manifest with progressive neurological deficits. It is characterized by abnormal accumulation of unencapsulated epidural fat commonly associated with the administration of exogenous steroids associated with a variety of systemic diseases, endocrinopathies, and Cushing syndrome (Fogel et al. Spine J 5:202-211, 2005). Occasionally, spinal epidural lipomatosis may occur in patients not exposed to steroids or in patients with endocrinopathies, primarily in obese individuals (Fogel et al. Spine J 5:202-211, 2005). However, spinal lumbar epidural lipomatosis resulting from local steroid injection has rarely been reported. We report the case of a 45-year-old diabetic man with claudication that was probably due to symptomatic lumbar spinal lipomatosis resulting from a single local epidural steroid injection.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2018

Extraction of Microcrystalline Cellulose from Cotton Sliver and Its Comparison with Commercial Microcrystalline Cellulose

The work was aimed at the extraction of microcrystalline cellulose (EMC) from raw cotton sliver (RCS) by acid hydrolysis using sulphuric acid. The EMC was characterized and compared with commercial grade microcrystalline cellulose (CMC). Basic chemical pretreatments, bleaching and scouring were given to the RCS before extraction to remove natural colourants and hydrophobic impurities like oils, waxes, minerals, fats etc. The properties of EMC and CMC are considerably different from the RCS. Average particle size obtained was around 5–10 µm for EMC and CMC respectively. The EMC suspension was more stable than CMC suspension. The RCS, EMC and CMC were characterized by using X-ray diffraction, thermogravimetric analysis, Fourier transform infrared spectroscopy, scanning electronic microscopy and contact angle. EMC prepared from RCS has properties at par with CMC. Cotton being rich in cellulose content can be potentially used as the source for microcellulose extraction, particularly in the production of hydrophilic microcomposites.

36 MATERIALS SCIENCE↗

DOE OSTI2019

Physicochemical, Microstructural and Thermal Characterization of Chitosan from Blue Crab Shell Waste and Its Bioactivity Characteristics

The aim of the present study was to characterize the chitosan synthesized from blue crab (Callinectes sapidus, Rathbun, 1986) shell waste and to investigate its physicochemical and microstructural analyses as well as its antioxidant and antibacterial potentials. Microstructural and elemental characterization of the synthesized and commercial chitosan powders were performed using fourier transform infra-red spectroscopy, scanning electron microscopy and energy dispersive X-ray spectroscopy. Thermal analysis were done using thermogravimetric analysis. Antioxidant and antimicrobial analysis were done using by DPPH (1,1-diphenyl-2-picrylhydrazyl) free radical scavenging assay and agar well diffusion assay, respectively. The yield of the synthesized chitosan was calculated as 7.47% with moisture and ash contents of 0.151 ± 0.0025% and 0.19 ± 0.01%, respectively. Synthesized chitosan demonstrated the values of degree of deacetylation (71%), water (620.029 ± 52.59%) and fat (437.93 ± 15.92%) binding capacities, solubility (94.15 ± 2.84%), viscosity (463.25 ± 13.10 cPs) and whiteness (90.23 ± 0.27%). Antioxidant activity of synthesized chitosan was found to be moderate (55.30 ± 5.05%) when compared to ascorbic acid standard (87.61 ± 1.34). Chitosan obtained from blue crab shell also showed moderate antibacterial activity against Staphylococcus aureus and Escherichia coli. The findings of the study indicated that blue crab shell waste might be a potentially effective biopolymer source for commercial applications especially in food industry.

36 MATERIALS SCIENCE↗

DOE OSTI2018

Tail Behaviour of Self-Similar Profiles with Infinite Mass for Smoluchowski’s Coagulation Equation

In this article, we consider self-similar profiles to Smoluchowski’s coagulation equation for which we derive the precise asymptotic behaviour at infinity. More precisely, we look at so-called fat-tailed profiles which decay algebraically and as a consequence have infinite total mass. The results only require mild assumptions on the coagulation kernel and thus cover a large class of rate kernels.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

DOE OSTI2019

Postmastectomy radiation therapy using VMAT technique for breast cancer patients with expander reconstruction

Postmastectomy radiotherapy (PMRT) following immediate breast reconstruction is increasingly adopted in the management of breast cancer patients. We retrospectively evaluate the complication rates of PMRT using VMAT technique to immediate tissue expander-based reconstructions and the possible impact of tissue expander volume on radiotherapy planning. We reviewed the data of patients who underwent immediate expander breast reconstruction and received PMRT with VMAT (50 Gy in 25 fractions) on the reconstructed breast and axillary levels III–IV. Neoadjuvant or adjuvant systemic therapy was administered in most of the patients. Autologous fat grafting was routinely performed at the time of second-stage reconstruction. Between 2015 and 2017, PMRT was delivered to 46 consecutive patients (median age 50 years) with expander reconstruction. Median follow-up was 27 months (range 10–41). Two patients (4.3%) had a reconstruction failure, as expander rupture and infection, following the first- and the second-stage reconstruction, respectively. In most cases expanders were completely inflated before PMRT (65.2%). Median expander volume before PMRT was 425 cm{sup 3} (range 150–700 cm{sup 3}). The amount of expander inflation did not significantly affect dosimetry, except for skin dose, with a surface receiving more than 30 Gy of 36.6 ± 0.9 cm{sup 2} and 47.0 ± 2.5 cm{sup 2} for a volume expander below or above the median, respectively. However, this variable was not predictor for complications. Disease progression was recorded in 15.2% of patients. PMRT using VMAT technique for breast cancer patients with expander reconstruction is associated with a very low complication rate. The expander volume before PMRT does not significantly compromise radiotherapy dose distribution.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2019

FDG PET-CT findings of extra-thoracic sarcoid are associated with cardiac sarcoid: A rationale for using FGD PET-CT for cardiac sarcoid evaluation

Purpose: This retrospective study investigates the relationship between cardiac and extra-thoracic sarcoid findings on FDG PET-CT using a 72-hour pretest high-fat, high-protein, and very low-carbohydrate (HFHPVLC) diet. Patients and methods: A total of 196 consecutive FDG PET-CT scans with 72-hour HFHPVLC diet preparation were performed between December 2014 and December 2015 in known sarcoid patients. Of these scans, 5 were excluded for non-adherence to diet preparation or underlying cancer. Cardiac and extra-thoracic sarcoid lesions were categorized and measured for radiotracer uptake. Results: A total of 188 patients had 191 eligible FDG PET/CT scans (3 follow-up scans), of which there were 20 (10%) positive, 6 indeterminate (3%), and 165 (86%) negative for CS. Among the 20 scans positive for CS, 8 (40%) had findings of both cardiac and extra-thoracic sarcoid. Conclusion: Our study shows that 40% of CS patients also have FDG PET-CT findings of extra-thoracic sarcoid. This makes an intriguing case for FDG PET-CT use with pretest diet prep over cardiac MRI (CMR) for cardiac sarcoid evaluation, given that CMR is likely to overlook these extra-thoracic sites of disease.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2019

Development of an inflammation imaging tracer, {sup 111}In-DOTA-DAPTA, targeting chemokine receptor CCR5 and preliminary evaluation in an ApoE{sup −/−} atherosclerosis mouse model

Background: Chemokine receptor 5 (CCR5) plays an important role in atherosclerosis. Our objective was to develop a SPECT tracer targeting CCR5 for imaging plaque inflammation by radiolabeling D-Ala-peptide T-amide (DAPTA), a CCR5 antagonist, with {sup 111}In. Methods: 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) conjugated DAPTA (DOTA-DAPTA) was labeled with {sup 111}In. Cell uptake studies were conducted in U87-CD4-CCR5 and U87-MG cells. Biodistribution was determined in C57BL/6 mice. Autoradiography, en face and Oil Red O (ORO) imaging studies were performed in ApoE{sup −/−} mice. Results: DOTA-DAPTA was radiolabeled with {sup 111}In with high radiochemical purity (> 98%) and specific activity (70 MBq·nmol). {sup 111}In-DOTA-DAPTA exhibited fast blood and renal clearance and high spleen uptake. The U87-CD4-CCR5 cells had significantly higher uptake in comparison to the U87-MG cells. The cell uptake was reduced by three times with DAPTA, indicating the receptor specificity of the uptake. Autoradiographic images showed significantly higher lesion uptake of {sup 111}In-DOTA-DAPTA in ApoE{sup −/−} mice than that in C57BL/6 mice. The tracer uptake in 4 month old ApoE{sup −/−} high fat diet (HFD) mice with blocking agent was twofold lower than the same mice without the blocking agent, demonstrating the specificity of the tracer for the CCR5 receptor. Conclusion: {sup 111}In-DOTA-DAPTA, specifically targeting chemokine receptor CCR5, is a potential SPECT agent for imaging inflammation in atherosclerosis.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2019

Could FDG-PET imaging play a role in the detection of progressing atherosclerosis in HIV-infected patients?

Important progresses in the management of patients with human immunodeficiency virus, in particular the advent of new anti-retroviral therapies (ART), have turned this rapidly fatal condition into a controllable chronic disease with a life expectancy that approaches the one from the general population. Cardiovascular diseases have now become one of the leading causes of non-HIV-related mortality in this population. Several factors including the presence of HIV in the vascular wall and the development of dyslipidemia and alteration in body fat distribution under ART might play a role the progression of atherosclerosis in HIV-infected patients. The use of imaging biomarkers may help to identify the factors associated with an increased risk of cardiovascular events and select high-risk patients who will benefit the most from the early implementation of preventive treatments.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2019

Aerobic oxidation of glycerol catalyzed by M salts of PMo 12 O 40 3- (M = K + , Zn 2+ , Cu 2+ , Al 3+ , Cr 3+ , Fe 3+ )

Glycerol is a co-product in the manufacture of biodiesel from vegetable oil and animal fat. A significant increase in biodiesel production results in adramatic overproduction of glycerol. The oxidation of glycerol to lactic acid (LA) by O 2 is considered to be a promising technology to increase the value of glycerol. Studies on the fundamental reaction mechanism vary for different catalytic systems. Here in this work we have chosen Keggin polyoxometalates (POMs) as an exemplary family of water-soluble hydrolytically and oxidatively-stable, fully-inorganic complexes with transition-metal and non-transition-metal counter-cations (M in the formula, MPMo 12 O 40 , where M = H + , K + , Zn 2+ , Cu 2+ , Al 3+ , Cr 3+ , Fe 3+ in appropriate number to counterbalance the 3- charge of PMo 12 O 40 3- ). Reactions involving hydrogen peroxide, an intermediate during glycerol oxidation, produce free radicals. A kinetic analysis reveals that the radical chain length under typical conditions is about 20–30. After minimal optimization, the yield of LA was 88% at glycerol conversion > 97% (1.0 M aqueous solution of glycerol, 4.0 mM of the Al salt of PMo 12 O 40 3- , henceforth “AlPMo”, 10 bar O 2 at 60 °C, reaction time 6.0 h).

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗