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Stratospheric emission spectra in the submillimeter range have been recorded with a resolution of 0.0033/cm with a balloon-borne interferometer. Several minor atmospheric constituents have been identified in a preliminary analysis of the spectra; these are water vapor, oxygen, ozone isotopes, nitric acid, nitrous oxide, hydrofluoric and hydrochloric acids, and carbon monoxide.
Background: In animal models of heart failure (HF), myocardial metabolism shifts from high-energy fatty acid (FA) metabolism toward glucose. However, FA (vs glucose) metabolism generates more ATP/mole; thus, FA metabolism may be especially advantageous in HF. Sex modulates myocardial blood flow (MBF) and substrate metabolism in normal humans. Whether sex affects MBF and metabolism in patients with HF is unknown. Methods and Results: We studied 19 well-matched men and women with nonischemic HF (EF ≤ 35%). MBF and myocardial substrate metabolism were quantified using positron emission tomography. Women had higher MBF (mL/g/minute), FA uptake (mL/g/minute), and FA utilization (nmol/g/minute) (P < 0.005, P < 0.005, P < 0.05, respectively) and trended toward having higher FA oxidation than men (P = 0.09). These findings were independent of age, obesity, and insulin resistance. There were no sex-related differences in fasting myocardial glucose uptake or metabolism. Higher MBF was related to improved event-free survival (HR 0.31, P = 0.02). Conclusions: In nonischemic HF, women have higher MBF and FA uptake and metabolism than men, irrespective of age, obesity, or insulin resistance. Moreover, higher MBF portends a better prognosis. These sex-related differences should be taken into account in the development and targeting of novel agents aimed at modulating MBF and metabolism in HF.
We have studied the etching properties of silicon-on-insulator (SOI) substrates in recently developed chromium-free solutions containing halogens. We have shown that the presence of halogen compounds X (I{sup -}, Br{sup -}...) in HF/HNO{sub 3}/CH{sub 3}COOH solutions is required for a selective and preferential etching on SOI. The etching rate of such solutions increases with the dissolved halogen concentrations. The chemical reactivity of Si-X (X = Br{sup -}, I{sup -}..) bonds has been analyzed by X-ray Photoelectron Spectroscopy (XPS), Pseudo-MOS (flatband potential) and Kelvin Force Microscopy (KFM) measurements. A negative shift of flatband potential values is explained by an increasing concentration of halogen compounds in the solution and a substitution of Si-H (F) bonds by Si-X bonds during the reaction. Though Si-X bonds, and more particularly Si-I bonds, have been confirmed only at trace levels using XPS, we believe that the formation of Si-X bonds is supported by a mechanism of surface dipoles. Unexpectedly, no significant change in work function could be detected using KFM measurements. Some suggestions, based on KFM technique improvements, are made to explain such results. Finally, though the interaction mechanism between silicon, fluoride, iodide, and nitric acid is not clearly elucidated by our experimental results, the formation of Si-halogen bonds is crucial for etching and defect decoration capability.
A high-fat diet (HF) is associated with obesity, insulin resistance, and hyperglycemia. Animal studies have shown compensatory mechanisms in pancreatic β-cells after high fat load, such as increased pancreatic β-cell mass, enhanced insulin secretion, and exocytosis. However, the effects of high fat intake on insulin synthesis are obscure. Here, we investigated whether insulin synthesis was altered in correlation with an HF diet, for the purpose of obtaining further understanding of the compensatory mechanisms in pancreatic β-cells. Mice fed an HF diet are obese, insulin resistant, hyperinsulinemic, and glucose intolerant. In islets of mice fed an HF diet, more storage of insulin was identified. We analyzed insulin translation in mouse islets, as well as in INS-1 cells, using non-radioisotope chemicals. We found that insulin translational levels were significantly increased in islets of mice fed an HF diet to meet systemic demand, without altering its transcriptional levels. Our data showed that not only increased pancreatic β-cell mass and insulin secretion but also elevated insulin translation is the major compensatory mechanism of pancreatic β-cells. - Highlights: • More stored insulin was recognized in islets of mice fed a high-fat diet. • Insulin translation was not enhanced by fatty acids, but by insulin demand. • Insulin transcription was not altered in islets of mice fed a high-fat diet. • Insulin translation was markedly enhanced in islets of mice fed a high-fat diet. • Non-radioisotope chemicals were used to measure insulin translation in mouse islets.
Granite rock comprising anorthoclase-type albite and quartz as its major phases and biotite mica as the minor one was exposed to supercritical carbon dioxide (scCO 2 )/water at 250 C and 13.78 MPa pressure for 104 hours. For comparison purpose, four other rocks, albite, hornblende, diorite, and quartz, also were exposed. During the exposure of granite, ionic carbonic acid, known as the wet carbonation reactant, preferentially reacted with anorthoclase-type albite and biotite, rather than with quartz. The susceptibility of biotite to wet carbonation was higher than that of anorthoclase-type albite. All the carbonation by-products of anorthoclase-type albite were amorphous phases including Na- and K-carbonates, a kaolinite clay-like compound, and silicon dioxide, while wet carbonation converted biotite into potassium aluminum silicate, siderite, and magnesite in crystalline phases and hydrogen fluoride (HF). Three of these reaction by-products, Na- and K-carbonates and HF, were highly soluble in water. Correspondingly, the carbonated top surface layer, about 1.27 mm thick as carbonation depth, developed porous microstructure with numerous large voids, some of which have a size of ≥10 μm, reflecting the erosion of granite by the leaching of these water-soluble reaction by-products. Comparing with this carbonation depth, its depth of other minerals was considerable lower, particularly, for hornblende and diorite with 0.07 and 0.02 mm, while no carbonate compound was detected in quartz. The major factor governing these low carbonation depths in these rocks was the formation of water-insensitive scale-like carbonate by-products such as calcite (CaCO 3 ), siderite (FeCO 3 ), and magnesite (MgCO 3 ). Their formation within the superficial layer of these minerals served as protective barrier layer that inhibits and retards further carbonation of fresh underlying minerals, even if the exposure time was extended. Thus, the coverage by this barrier layer of the non-carbonated surfaces of the underlying rock was reason why the hornblende and diorite exhibited a minimum depth of carbonation. Under exposure to the scCO 2 /water at 200 C and 10.34 MPa pressure for up to 42 days, the ranking of the magnitude of erosion caused by wet carbonation was in the following order; granite > albite > hornblende > diorite > quartz. The eroding-caused weight loss of granite (0.88 %) was ~2.4, ~5.2, ~9.8, and ~17.6 times greater than that of albite, hornblends, diorite, and quartz, respectively.
The NREL "black silicon" nanocatalytic wet-chemical etch is an inexpensive, one-step method to minimize reflections from crystalline silicon solar cells. The technology enables high-efficiency solar cells without the use of expensive antireflection coatings.
Free-standing layers of porous silicon with a thickness ranging from 50 to 200 {mu}m have been fabricated using an electrolyte composed of HF and acetic acid. Chemical aspects of the etching process associated with the evolution of gases that favor detachment of layers from substrates are considered. The layers exhibit stable photoluminescence in the visible spectral region observed from both of their sides.
In this paper, we will show that efficiency of multi-crystalline silicon (mc-Si) solar cells may be improved by acid texturization. In order to enhance overall efficiency of mc-Si for solar-cell applications, the surface treatment of texturization with wet etching using appropriate solutions can improve incident light into the cell. Alkali etchant cannot produce uniformly textured surface to generate enough open circuit voltage (V{sub OC}) and high efficiency of the mc-Si due to the unavoidable grain randomly oriented with higher steps formed during etching process. Optimized acid etching conditions can be obtained by decreasing the reflectance (R) for mc-Si substrate below levels generated by alkali etching. Short-circuit current (I{sub SC}) measurements on acid textured cells reveal that current gain can be significantly enhanced by reducing reflection. The optimal acid etching ratio HF:HNO{sub 3}:H{sub 2}O = 15:1:2.5 with etching time of 60 s and lowering 42.7% of the R value can improve 112.4% of the conversion efficiency ({eta}) of the developed solar cell. In order to obtain more detailed information of different defect region, high-resolution light beam induced current (LBIC) is applied to measure the internal quantum efficiency (IQE) and the lifetime of minority carriers. Thus, the acid texturing approach is instrumental to achieve high efficiency in mass production using relatively low-cost mc-Si as starting material with proper optimization of the fabrication steps. (author)
A new layered indium-organic framework material, In[NC{sub 5}H{sub 3}(CO{sub 2}){sub 2}](OH{sub 2})F has been synthesized by a hydrothermal reaction using In{sub 2}O{sub 3}, NH{sub 4}F, 2,6-NC{sub 5}H{sub 3}(CO{sub 2}H){sub 2} (2,6-pyridinedicarboxylic acid), HF, and water at 200 {sup o}C. Single-crystal X-ray diffraction was used to determine the structure of the reported material. In[NC{sub 5}H{sub 3}(CO{sub 2}){sub 2}](OH{sub 2})F has a novel layered structure consisting of InO{sub 5}NF polyhedra and the pyridinedicarboxylate organic linker. Detailed structural analyses with full characterization including infrared spectrum, thermogravimetric analysis, elemental analysis, exchange reactions for the coordinated water molecule, and gas adsorption experiments are reported. - Graphical abstract: Wire representation for the one indium-organic layer of In[NC{sub 5}H{sub 3}(CO{sub 2}){sub 2}](OH{sub 2})F in the [101] direction. Strong hydrogen bonds between the coordinated F and water molecules are observed within the layer.
The actinide engineering and science group (MET-1) have completed simultaneous thermal analysis and offgas analysis by mass spectrometry (STA-MS) of remediated nitrate salt (RNS) surrogates formulated by the high explosives science and technology group (M-7). The 1.0 to 1.5g surrogate samples were first analyzed as received, then a new set was analyzed with 100-200mL 10M HNO 3 +0.3 MHF added, and a third set was analyzed after 200 mL of a concentrated Pu-AM spike (in 10M HNO 3 +0.3 MHF) was added. The acid and spike solutions were formulated by the actinide analytical chemistry group (C-AAC) using reagent-grade HNO 3 and HF, which was also used to dissolve a small quantity of mixed, high-fired PuO 2 / AmO 2 oxide.
We have developed the multicomponent hybrid density functional theory [MC-(HF+DFT)] method with polarizable continuum model (PCM) for the analysis of molecular properties including both nuclear quantum effect and solvent effect. The chemical shifts and H/D isotope shifts of the picolinic acid N-oxide (PANO) molecule in chloroform and acetonitrile solvents are applied by B3LYP electron exchange-correlation functional for our MC-(HF+DFT) method with PCM (MC-B3LYP/PCM). Our MC-B3LYP/PCM results for PANO are in reasonable agreement with the corresponding experimental chemical shifts and isotope shifts. We further investigated the applicability of our method for acetylacetone in several solvents.
A new thiophene derivative, 3-bromo-2-methyl-5-(4-nitrophenyl)thiophene (2), was synthesized through the Suzuki coupling reaction of 4-bromo-5-methylthiophen-2-ylboronic acid (1) and 4-iodonitrobenzene, and its structure was confirmed by nuclear magnetic resonance (NMR), low and high resolution mass spectrometry (HRMS), Fourier transform infrared spectroscopy (FT-IR), and X-ray investigations of the crystal structure. The FT-IR spectra (4000–400 cm{sup –1}), Raman spectra (4000–100 cm{sup –1}), and theoretical vibrational frequencies of this new substance were investigated. Its theoretically established geometric parameters and calculated vibrational frequencies are in good agreement with the reported experimental data. The highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energies and other related parameters of the compound were calculated. The ionization potentials given by the B3LYP and HF (Hartree–Fock) methods for this new compound are –0.30456 and –0.30501 eV, respectively.
Progressive dissolution of the Murchison carbonaceous chondrite with acids of increasing strengths reveals large internal W isotope variations that reflect a heterogeneous distribution of s- and r-process W isotopes among the components of primitive chondrites. At least two distinct carriers of nucleosynthetic W isotope anomalies must be present, which were produced in different nucleosynthetic environments. The co-variation of {sup 182}W/{sup 184}W and {sup 183}W/{sup 184}W in the leachates follows a linear trend that is consistent with a mixing line between terrestrial W and a presumed s-process-enriched component. The composition of the s-enriched component agrees reasonably well with that predicted by the stellar model of s-process nucleosynthesis. The co-variation of {sup 182}W/{sup 184}W and {sup 183}W/{sup 184}W in the leachates provides a means for correcting the measured {sup 182}W/{sup 184}W and {sup 182}W/{sup 183}W of Ca-Al-rich inclusions (CAI) for nucleosynthetic anomalies using the isotopic variations in {sup 183}W/{sup 184}W. This new correction procedure is different from that used previously, and results in a downward shift of the initial {epsilon}{sup 182}W of CAI to -3.51 {+-} 0.10 (where {epsilon}{sup 182}W is the variation in 0.01% of the {sup 182}W/{sup 183}W ratio relative to Earth's mantle). This revision leads to Hf-W model ages of core formation in iron meteorite parent bodies that are {approx}2 Myr younger than previously calculated. The revised Hf-W model ages are consistent with CAI being the oldest solids formed in the solar system, and indicate that core formation in some planetesimals occurred within {approx}2 Myr of the beginning of the solar system.
The Fourier transform infrared (FT-IR) and Fourier transform Raman (FT-Raman) spectra of 2,6-dibromo-3-chloro-4-fluoroaniline in the solid phase were recorded and analyzed. Quantum chemical calculations of the optimized molecular structure, energies, nonlinear optical (NLO) analysis, molecular surfaces, and vibrational analysis of this substance were performed. The obtained results on the geometric structure and vibrational frequencies were compared with the observed data. The calculated highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energies also confirm that charge transfer occurs within the molecule. The detailed vibrational assignments were performed using the HF and DFT calculations, and the potential energy distribution (PED) was obtained by the vibrational energy distribution analysis (VEDA4) program. Finally, the effects of the amino, bromo, chloro, and fluoro substituents on the vibrational frequencies were investigated.
Carbon anodes, which are consumed in aluminum electrolysis, are fabricated in separate anode plants where coke and pitch are mixed and vibrocompacted to green anode blocks before being baked in anode baking furnaces. The chemical environment inside an anode baking furnace is found to play an important role in the degradation of the furnace refractory lining. In this work, the pit gas composition was recorded during anode baking by a Fourier transformed infrared spectroscopy (FTIR) spectrometer and a gas chromatograph. The temperature dependence of the concentration of gas species during baking was obtained based on three measurement campaigns. The concentrations of CO and CO{sub 2} were found to be dependent on temperature, where the concentration of CO peaked around the maximum firing temperature. In addition to varying concentrations of CH{sub 4} and HF, water was found in large amounts in the first part of the baking cycle. The water originates to some extent from the cooling of the green anodes after vibrocompaction and is potentially important with respect to the chemical stability of the refractory lining. The variations in pit gas composition are related to operational parameters and are discussed in relation to refractory degradation phenomena.
Aim: The aim of this study was to compare CZT-SPECT (CZT SPECT) to conventional SPECT (C-SPECT) in the assessment of left ventricular myocardial scar, contractile function, and mechanical synchrony in patients with heart failure (HF). Methods: Fifty-nine patients with HF who were referred for myocardial perfusion/metabolism imaging were enrolled. All patients underwent resting {sup 99m}Tc-MIBI gated myocardial perfusion imaging using a CZT SPECT camera and a C-SPECT camera, respectively, and {sup 18}F-FDG PET myocardial metabolism imaging within three days. Summed rest score (SRS) and total perfusion defect (TPD) (as indices of perfusion abnormality), left ventricular (LV), end diastolic volume (EDV), end systolic volume (ESV), and ejection fraction (EF) (as indices of LV systolic function), and histogram band width (BW) and standard deviation (SD) (as indices of mechanical synchrony) were analyzed by automated software while the perfusion/metabolism patterns were analyzed visually. Results: There was a good correlation between CZT SPECT and C-SPECT for SRS and TPD. CZT SPECT tended to underestimate SRS and TPD compared to C-SPECT. CZT-SPECT and C-SPECT showed excellent agreement in assessing the perfusion/metabolism pattern though a small proportion of normal segments (6.6%) identified by CZT/PET exhibited mismatch pattern on C-SPECT/PET. CZT SPECT also showed excellent correlation with C-SPECT in measuring EDV, ESV, and EF. Finally, BW and SD measured by CZT SPECT correlated well with C-SPECT but CZT SPECT tended to overestimate BW and SD compared to C-SPECT. Conclusion: CZT SPECT provided comparable data to C-SPECT for measuring LV scar, function and synchrony at a considerable reduction in imaging time. CZT SPECT holds a promise for comprehensive evaluation of myocardial performance in patients with HF.
Background: Non-invasive approaches to investigate myocardial efficiency can help track the progression of heart failure (HF). This study evaluates the repeatability and reproducibility of {sup 11}C-acetate positron emission tomography (PET) imaging of oxidative metabolism. Methods and results: Dynamic {sup 11}C-acetate PET scans were performed at baseline and followup (47 ± 22 days apart) in 20 patients with stable HF with reduced ejection fraction. Two observers blinded to patients’ clinical data used FlowQuant{sup ®} to evaluate test–retest repeatability, as well as intra- and inter-observer reproducibility of {sup 11}C-acetate tracer uptake and clearance rates, for the measurement of myocardial oxygen consumption (MVO{sub 2}), myocardial external efficiency (MEE), work metabolic index (WMI), and myocardial blood flow. Reproducibility and repeatability were evaluated using intra-class-correlation (ICC) and Bland–Altman coefficient-of-repeatability (CR). Test–retest correlations and repeatability were better for MEE and WMI compared to MVO{sub 2}. All intra- and inter-observer correlations were excellent (ICC = 0.95-0.99) and the reproducibility values (CR = 3%-6%) were significantly lower than the test–retest repeatability values (22%-54%, P < 0.001). Repeatability was improved for all parameters using a newer PET–computed tomography (CT) scanner compared to older PET-only instrumentation. Conclusion: {sup 11}C-acetate PET measurements of WMI and MEE exhibited excellent test–retest repeatability and operator reproducibility. Newer PET–CT scanners may be preferred for longitudinal tracking of cardiac efficiency. [French] French Abstract: Contexte: Les examens non invasifs de la fonction myocardique aident à suivre la progression de l’insuffisance cardiaque. Dans ce travail, nous avons évalué la répétabilité et la reproductibilité de l’étude du métabolisme oxydatif du myocarde par imagerie tomographique à positrons avec l’acétate marqué au carbone 11. Méthodes et résultats: Une étude de base et un second examen TEP dynamique à l’ acétate marqué au carbone 11 ont été réalisés (47 ± 22 jours) chez 20 patients présentant une insuffisance cardiaque stable avec une fraction d’éjection réduite. Sans aucune connaissance des données cliniques et au moyen du programme FlowQuant®, deux observateurs ont évalué la répétabilité des TEPs de base et de leur suivi, la reproductibilité intra- et inter-observateur, l’absorption et la clearance du traceur, la mesure de la consommation d’oxygène du myocarde (MVO2), l’efficacité contractile du myocarde (MEE), l’index métabolique du travail myocardique (WMI) et le débit sanguin myocardique (MBF). La reproductibilité et la répétabilité ont été évaluées en utilisant la corrélation intra-classe (ICC) et le coefficient de répétabilité Altman (CR). Les corrélations entre les études de base et leur suivi et la répétabilité des données se sont avérées supérieures pour les paramètres MEE et WMI par rapport à MVO2. Toutes les corrélations intra- et inter-observateurs furent excellentes (ICC = 0,95-0,99). Les valeurs de reproductibilité (CR = 3-6%) furent significativement inférieures aux valeurs de répétabilité (22-54%, p <0.001). La répétabilité des paramètres mesurés s’est avérée supérieure avec un scanner TEP-TDM de nouvelle génération par rapport à l’utilisation de la TEP sans TDM Conclusion: Les mesures réalisées dans cette étude TEP 11C-acétate montre une excellent répétabilité et reproductibilité des paramètres WMI et WMI entre les examens de base et leur suivi effectués par des opérateurs différents. Les nouveaux scanners TEP-TDM devraient être préférés pour le suivi longitudinal de la fonction cardiaque. [Spanish] Spanish Abstract: Antecedentes: el abordaje no invasivo para investigar la eficiencia miocárdica puede ayudar en el seguimiento de la progresión de la insuficiencia cardíaca. Este estudio evalúa la repetibilidad y la reproducibilidad del estudio de metabolismo oxidativo con PET 11C-acetato. Métodos y resultados: Se realizaron estudios de PET 11C-acetato dinámicos al inicio y durante el seguimiento (47 ± 22 días de diferencia) en 20 pacientes con insuficiencia cardíaca estable y fracción de eyección reducida. Dos observadores cegados a los datos clínicos de los pacientes utilizaron FlowQuant® para evaluar la repetibilidad de la prueba-reprueba, así como la reproducibilidad intra e interobservador de la captación de radiotrazador 11C-acetato y sus tasas de eliminación, la medición del consumo miocárdico de oxígeno (MVO2), la eficiencia externa miocardica (EEM), el índice trabajo-metabólico (ITM) y flujo sanguíneo miocárdico (FSM). La reproducibilidad y la repetibilidad se evaluaron mediante la correlación intraclase (ICC) y el coeficiente de repetibilidad (CR) de Bland-Altman. Las correlaciones Prueba-Reprueba y la repetibilidad fueron mejores para la EEM y el ITM en comparación con el MVO2. Todas las correlaciones intra e interobservador fueron excelentes (ICC = 0.95-0.99) y los valores de reproducibilidad (CR = 3-6%) fueron significativamente menores que los valores de repetibilidad prueba-reprueba (22-54%, p <0.001). La repetibilidad fue mejor para todos los parámetros utilizando un equipo PET-TC más nuevo en comparación con un equipo PET sin CT. Conclusión: las mediciones del PET con 11C-acetato del ITM y EEM mostraron una excelente repetibilidad prueba-preprueba y reproducibilidad del operador. Los nuevos equipos PET-CT pueden ser elegidos para el seguimiento longitudinal de la eficiencia miocárdica. [Chinese] Chinese Abstract: 背景: 采用非侵入式方法来研究心肌代谢效率可以帮助追踪心力衰竭的过程。本研究评估利用碳-11 醋酸盐为 PET 显影剂行氧化代谢成像的可重复性和可再现性。 方法和结果: 纳入射血分数减低的 20 名稳定性心衰患者,对患者基线和 47±22 天随访都进行碳-11 醋酸盐 PET 扫描。为测量心肌耗氧量(MVO{sub 2}), 心肌外效率(MEE), 工作代谢指标(WMI)和心肌血流量(MBF), 两名观察者按照双盲的方法利用 FlowQuant®对碳-11 醋酸盐的摄取率和清空率进行了重复性测试以及不同观察者之间的可再现性测试。采用组内相关系数(ICC)和 Bland Altman 可重复性系数(CR)分别对可再现性和可重复性进行评估。MEE 和 WMI 的两次试验系数和可重复性优于MVO{sub 2}。所有观察者之间的相关系数都较好(ICC=0.95-0.99),可再现性系数的值(CR=3-6%)明显低于两次试验可重复性的值(22-54%, P<0.001)。相比于旧的只有 PET 的设备, 采用新型 PET-CT 扫描仪能够使所有参数的可再现性都有所提高。 结论: 碳-11醋酸盐 PET 显像测量 WMI 和 MEE 有很好的可重复性和可再现性。新的 PET-CT 扫描仪可能更适合于心脏代谢效率的长期追踪。.
Cardiac denervation is associated with progressive left ventricular (LV) dysfunction, ventricular arrhythmias, and sudden cardiac death (SCD) in heart failure (HF). In this regard, it is important to evaluate cardiac-specific sympathetic nervous system (SNS) function. The radiotracer Iodine-123 meta-iodobenzylguanidine ({sup 123}I-mIBG) can noninvasively evaluate pre-synaptic SNS function. Recent multicenter trials have shown {sup 123}I-mIBG to have strong predictive value for fatal arrhythmias and cardiac death in HF. {sup 123}I-mIBG was initially developed in the USA in the 1970s. In 1992, the Japanese Ministry of Health and Labour approved {sup 123}I-mIBG for the assessment of cardiac function. Following approval, the Japanese nuclear cardiology community developed {sup 123}I-mIBG imaging services in various medical centers. Japanese groups have been trying to establish the clinical utility of {sup 123}I-mIBG and standardize parameters for data acquisition and image analysis. The US Food and Drug Administration (FDA) has approved clinical use of {sup 123}I-mIBG for cardiac and non-cardiac imaging. However, clinical use of {sup 123}I-mIBG in the US has been very limited. The number of {sup 123}I-mIBG studies in Japan has also been limited. There are similarities and differences between the two countries. To establish the clinical utility of {sup 123}I-mIBG in both countries, it is important to characterize the situations of {sup 123}I-mIBG in each.