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The response of the trimethylammonium–iodinechloride and diiodide (TMA–ICl/I2) crystal structures have been examined under high pressure using neutron powder diffraction. TMA–ICl exhibits impressive pressure-driven electronic flexibility, where the N⋯I–Cl interactions progressively encompass all the distances represented in analogous structures recorded in the Cambridge Structural Database. Comparison with the TMA–I2 complex reveals that this flexibility is owed to the electronegativity of the chlorine atom which induces increased distortion of the iodine electron cloud. This structural flexibility may be influential in the future design of functional molecular materials. [ABSTRACT FROM AUTHOR]

The role of ingested fat in the etiology of obesity is controversial. The aims of this study were to determine the contributions of ingested fat oxidation to: 1) 24-h total energy expenditure (TEE), and 2) substrate oxidation during acute stationary cycle exercises in adult humans. Healthy, moderately obese (n = 18; BMI = 31 [+ or -] 1 kg/[m.sup.2]) subjects (8 men; 10 women) were each studied in a whole-room calorimeter for 24 h. They were fed mixed meals (55, 30, and 15% as energy from carbohydrate, fat and protein, respectively) to maintain energy balance. Each subject performed 1255-kJ cycle exercises at 50% V[O.sub.2max] in the calorimeter. Study test meal fat was labeled with carbon-13 ([sup.13]C). Ingested fat oxidation was estimated from breath [sup.13]C[O.sub.2] excretion and the subject's chamber C[O.sub.2] production. Total fat and carbohydrate oxidations were estimated from nonprotein respiratory quotient (NP-RQ) values. Endogenous fat oxidation was estimated as the difference between total fat and ingested fat oxidations. TEE was estimated from gas exchanges; 28 [+ or -] 3% of ingested fat was oxidized and it provided 8 [+ or -] 1% of 24-h TEE. During cycle exercises, ingested fat provided 50% of total fat oxidized and 13.0 [+ or -] 2% of energy expended. Endogenous fat oxidation contributed 10.4 [+ or -] 3% of energy expenditure during cycle exercises. This study extended to 24-h observations of previous studies that lasted 6-9 h on ingested fat oxidation in humans. Understanding the factors that promote ingested fat oxidation could lead to more effective obesity intervention programs. KEY WORDS: * fat * oxidation * mixed-meals * obesity